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[Display omitted] Scheme 1. Schematic illustration of the procedures for activation of WP. • Activating WP with K 2 C 2 O 4 , H 3 PO 4 or ZnCl 2 forms products of distinct nature. • H 3 PO 4 /ZnCl 2 catalyzes formed more bio-oil but less gas, and K 2 C 2 O 4 is opposite. • K 2 C 2 O 4 and ZnCl 2 are more effective than H 3 PO 4 for creating pores from WP. • ZnCl 2 creates abundant macropores via converting fibers in WP to graphitic crystals. • K 2 C 2 O 4 shows lower environmental impact than ZnCl 2 in activating WP. Waste paper (WP) is rich in cellulose, which can be activated to produce porous carbon, bio-oil, and combustible gases. During chemical activation of WP, the use of varied chemical agents not only generates activated carbon of distinct pore structure but also bio-oil/gases of different property. In this study, the activation of WP with varied chemical agents was conducted. The distinct characteristics of activated carbon and also bio-oil/gases were correlated with the different nature of the used chemical agents. The results indicated that H 3 PO 4 and ZnCl 2 catalyzed polymerization reactions for producing more bio-oil while less gases owing to their Brønsted and Lewis acidic sites. K 2 C 2 O 4 showed high activity for cracking/gasification reactions, forming bio-oil with higher abundance of organics with smaller π-conjugated structures. In addition, ZnCl 2 could create a very coarse porous structure with abundant macropores via destroying fiber structure in WP and promoting the growth of graphitic crystals. In comparison, K 2 C 2 O 4 hindered the aromatization and facilitated the formation of amorphous activated carbon. K 2 C 2 O 4 and ZnCl 2 were much more effective than H 3 PO 4 for creating micropores and mesopores from WP, the derived activated carbon showed superior performances as the electrode of supercapacitor and adsorbent for adsorption of oxytetracycline from aqueous solution. In addition, K 2 C 2 O 4 as activating agent showed lower environmental impact than ZnCl 2 in terms of energy consumption, environmental pollution and the greenhouse effect. [ABSTRACT FROM AUTHOR]

• A facile and economical strategy was proposed to fabricate paper-based electrode. • ACFPs obtained by high temperature activation still had flexible mechanical strength. • ACFPs supported the integration of high conductivity and electrochemical properties. • ACFPs also can serve as superior substrates for loading extra electroactive materials. • It shows broad application prospects in the field of energy storage. The cellulose-based paper electrode has attracted increasing attention for wearable and portable electronic devices. However, the loading of expensive electroactive substances, a large proportion of cellulose matrix and the loss of mechanical flexibility limit its commercial application. This article reports a facile and economical strategy for fabricating high-performance cellulose-based activated carbon fiber papers (ACFPs), which can be used as self-supporting supercapacitor electrodes without any binder. Combining wet papermaking, thermal carbonization, and double activation, the new strategy enables the in-situ transformation of fibrillated pulp fibers into cellulose-derived activated carbon fused with carbon fibers (CFs). The resulting ACFPs are characteristic of high specific surface area (808–1106 m2/g), high conductivity (1640–1786 S/m), prominent tensile strength (4.6–6.4 MPa), and flexible processability. Furthermore, the ACFP exhibits maximum specific capacitance of 48.8F/cm3 (or 165F/g) based on the whole electrode and possesses superior cycling stability. Moreover, electroactive materials are readily loaded onto the ACFPs to enhance the capacitance further. In the ACFPs, the cellulose-derived activated carbon is primarily responsible for capacitive energy storage, while CFs serve as a highly functional network due to their low thermal expansion coefficient and high electrical conductivity. Overall, this work provides a novel strategy for manufacturing scalable, cost-effective paper-based electrode materials with broad application prospects in energy storage. [ABSTRACT FROM AUTHOR]

• The 700 W is the best activation power. • Hydrogen is produced when LSC and KOH react. • The MLSC is microporous material compared with other active semi-coke. • MLSC-700 has finer micropores. • MLSC has a higher removal rate for substances smaller than 1356 Da. In view of the urgent need to treat biologically treated wastewater from pulp and paper mill (BTW) and the high cost of commercial activated carbon, microwave-assisted KOH activated lignite semi-coke (MLSC) was prepared for adsorption of BTW. Through the research, the best preparation conditions of MLSC are obtained (ratio of KOH/lignite semi-coke (LSC) = 1, radiation time 10 min, and microwave power 700 W). In order to further study the effect of microwave power, three kinds of MLSC were prepared under the conditions of 600 W (MLSC-600), 700 W (MLSC-700) and 800 W (MLSC-800), and a series of characterizations were performed. The research of coupled thermogravimetric and mass spectrometer system showed that KOH impregnated LSC produced hydrogen during pyrolysis, which proved that activation reaction took place between KOH and LSC. And pore characteristics study found that most of the pore size of MLSC was less than 0.7 nm, and MLSC-700 had finer micropores (0.6 nm< Ø <0.65 nm). The adsorption experiment showed that MLSC-700 had the best adsorption effect, the removal rates of COD and TOC can reach 96 % and 80 %. The Langmuir model and Elovich kinetic model can be used to fit adsorption isotherms and kinetics, respectively. It was found that due to the microporous structure of MLSC, the removal rate of low molecular weight pollutants (0−4500 Da) contained in BTW is very high. The microporous MLSC-700 prepared in this study is suitable for BTW treatment. [ABSTRACT FROM AUTHOR]

Abstract: Porous materials consisting of activated carbon and amorphous CaO–Al2O3–SiO2 (CAS) compound were prepared from refuse paper and plastic fuel (RPF), (a mixture of old paper and plastic) by carbonizing and/or activating treatments. Samples formed by chemical activation using K2CO3 showed a high specific surface area (S BET) of 1330m2/g but a lower ash content due to being washed after activation. By contrast, samples prepared by physical activation using steam showed rather lower S BET (510m2/g) due to higher ash contents. The physically activated samples showed much higher uptake properties for Ni2+ (a representative heavy metal) and phosphate ions (a representative of a harmful oxyanion) than the chemically activated samples because of the higher content of amorphous CAS in the former samples. By contrast, the chemically activated samples showed higher uptake for methylene blue (MB, a representative organic material) than the physically activated samples because of the higher activated carbon content of higher surface area. Although differences in the sorption properties for Ni2+, phosphate ion and MB were found between the physically and chemically activated samples, both samples show excellent multiple sorption properties for cation–anion combinations and inorganic–organic sorbents. [Copyright &y& Elsevier]

After normal alkali treatment process, the industrial Cr(VI) containing wastewater still contains a ppm level of Cr(VI) ions which should be further purified before discharging. In this study, the Cr(VI)-containing wastewater has been efficiently treated by the porous paper sludge-based activated carbon (ps AC) with an excellent specific surface area and rich oxygen functional groups. The batch experimental results showed that under acidic conditions, pH has little effect on the Cr(VI) removal. The kinetic and isotherms studies showed that the Elovich and Freundlich model could describe the adsorption process well and the maximum adsorption capacity of ps AC was 54.04 mg/g. The thermodynamic studies indicated that the reaction process was endothermic and spontaneous. Adsorption enthalpy was 17.37 kJ/mol, showing that the chemisorption process was a hydrogen bonding-controlled that has been also verified by some analytical techniques. Lastly, this study also provided an idea for reutilization of waster Cr(VI)-contained ps AC in furfural hydrogenation. Unlabelled Image • The effects of multiple factors on the performance of activated carbon • The highest Cr(VI) removal capacity of ps AC reached as high as 54.04 mg g−1. • Cr(VI) interacts with ps AC surface functional groups by hydrogen bonding. • Cr(VI)-contained ps AC was an excellent catalyst precursor. [ABSTRACT FROM AUTHOR]

The geopolymerization reaction is a chemical process involving the dissolution of amorphous, semi-crystalline and crystalline phases following alkaline or acid attack at ambient or at low temperature (T˂100 °C). Together with precondensed entities of the used activator solution the dissolved parts form a geopolymer network which glues together all remaining unreacted parts as ingredients of the artificial stone. The fate of the mineralogical phases present in the precursors used in the synthesis of alkaline and acid geopolymers is reviewed in this article. The different starting materials used in the synthesis of geopolymers and the different techniques used to modify the reactivity of these materials are reported. The mineralogical evolution of the amorphous, semi-crystalline and crystalline phases after activation at ambient and at low temperatures (T < 100 °C) is also reported. This study shows that for the mineralogical investigation of raw material, precursors and geopolymers, XRD is the most widely used analytical method. The most commonly used method to confirm the participation of crystalline phases in geopolymerization is the comparison of the diffractograms of the raw material to those of the products. It also indicates that, in addition to the amorphous aluminosilicate phases, certain semi-crystalline, and crystalline phases participate in this geopolymerization dynamic either by undergoing total or partial dissolution to form an inorganic macromolecule with an amorphous structure of the zeolitic type and other new minerals. The composition of the phases formed depends on the base material. Increasing the synthesis temperature promotes the dissolution of phases, the formation of geopolymer networks, and in some cases, the formation of new phases such as sodalities, zeolite A and zeolite P. Little work has been done to quantify the mineralogical phases before and after precursor activation, making it impossible to assess dissolution, the degree of geopolymerization, and mineral formation. The exact structure of the phases formed is often questionable, as most of the papers do not mention their reference structure number. There is also a lack of quantification of the amorphous phase resulting from the hardening of the activating solution and the evaluation of the fraction of the amorphous phase contained in the precursor remains unreacted. The mineralogical investigation must also extend to the quantification of phases using Rietveld refinement with internal standards to correlate these with the physical and mechanical properties of geopolymer products. Additional mineralogical study techniques, such as thin sections, should be used in future work for in-depth mineralogical investigation of geopolymers. [ABSTRACT FROM AUTHOR]

In this paper, we report the effect of adding the rare earth element lanthanum on the hydrogen storage properties of TiFe synthesized by mechanical alloying (MA). A remarkable improvement was observed in the first hydrogenation (activation) of La-added TiFe. Milling led to the refinement of the crystallite size of the TiFe alloy leading to nanocrystallinity. The formation of a stable hydride phase LaH 3 facilitated heterogeneous nucleation and acted as a gateway for the hydrogenation of the TiFe phase. No change in thermodynamics was observed for the rare earth-added TiFe compared to pure TiFe reported in the literature. The microstructure revealed a uniform distribution of the elements. However, La was completely immiscible with the TiFe alloy-a conclusion drawn from the thermodynamics study of the sample. Also investigated was pure TiFe synthesized by MA and arc melting to compare these two synthesis methods. • TiFe added with rare earth lanthanum was synthesized by mechanical alloying. • Uniform distribution of elements without the additive getting alloyed to TiFe. • Achieved remarkable improvement in the activation of the La-added TiFe. • No change in thermodynamics of the lanthanum-added TiFe compared to pure TiFe. • Highly stable LaH 3 phase facilitated heterogeneous nucleation and acted as a gateway for hydrogenation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Modified red mud-based materials can remove dyes from wastewater. • Four removal mechanisms of dye from wastewater are reviewed. • Future research of modified RM-based materials for dye removal are pointed out. Red mud (RM) is a highly alkaline solid waste generated during alumina production and should be disposed of and recycled in an environmentally sound manner. Red mud is rich in metal compounds, making it a promising material for environmental remediation treatment. However, there are fewer papers on the removal of organic dyes from wastewater using modified red mud-based materials. Therefore, this paper provides a comprehensive review on the properties of dyes and reveals the adverse effects caused by dye wastewater pollutants. The application of modified red mud-based materials in dye wastewater are further reviewed. Meanwhile, the removal mechanism includes electrostatic gravitational interaction, hydrogen bonding, π-π bonding, and catalytic oxidation. In addition, this paper suggests that the activation methods for red mud materials should be optimized in future studies as well as develops red mud-based materials with absorbing many dyes. This paper aims to expand modified red mud-based materials application for removing organic pullents from wastewater and red mud utilization. [ABSTRACT FROM AUTHOR]

• New experimental data on fragmentation of 200 MeV/u 40-Ar in copper. • Fine-resolution depth-profiles of nuclides induced by 200 MeV/u 40-Ar in copper. • FLUKA simulations of the experimental depth-profiles of the induced nuclides. • Comparison of the measured and simulated profiles. • Experimental data for development of physical models implemented in FLUKA. This work is a further contribution to our long-term experimental studies of activation- and fragmentation-related effects induced by high-energy heavy-ion irradiation in selected accelerator-construction materials. A stacked-foil copper target consisting of thin foils with different thicknesses was irradiated by 200 MeV/u 40Ar ions. Gamma spectra of the radiation emitted from the activated foils were measured and the nuclides created in the foils as a result of nuclear interaction between the 40Ar ions and the copper target nuclei were identified. The activities of all identified nuclides have been determined from the gamma spectra. The measured activity of each nuclide has been converted to the number of nuclei (of that nuclide) contained in the foil. Finally, the depth-profiles of the induced nuclides, i.e. the number of the induced nuclei as a function of the target depth, have been constructed and analyzed. The measured depth-profiles provide information on physical mechanisms of the high-energy heavy-ion fragmentation. The measured depth-profiles have been also compared with the simulated ones obtained with FLUKA2020. Keeping in mind complexity of the nucleus-nucleus interactions in the broad energy interval, the measured and simulated depth-profiles show a reasonable agreement. However, in some cases, discrepancies between the measured and the simulated depth-profiles have been observed. These cases are presented and discussed in the paper, as they can serve improvement of physical models implemented in the simulation codes. [ABSTRACT FROM AUTHOR]

As an important energy storage device, supercapacitors have been widely used in the field of energy storage. Biomass becomes an ideal source of carbon electrode material for supercapacitors due to its low cost, wide source, and environmental friendliness. In this paper, a detailed summary of the various methods of preparation and activation of biomass-derived carbon electrode materials was presented. Meanwhile, the methods of doping atoms to improve the electrochemical properties of carbon electrode materials were systematically categorized. In addition, three methods to improve the performance of supercapacitors had been summarized, i.e., the addition of organic acids to the hydrothermal carbonization process, the addition of redox additives/redox electrolytes, and the intensification of wood biochar monoliths. Some of the major application areas of supercapacitors were summarized, as well as an outlook on the future direction of supercapacitor development. This review can provide some creative insights into the study of biomass-derived carbon as an electrode material for supercapacitors. [Display omitted] • Biochar is used as electrode material for supercapacitors due to its physicochemical properties. • The doping modification methods of biochar are reviewed. • Three measures to enhance the performance of supercapacitors have been extensively analyzed. • Based on the advantages of supercapacitors, the application status in major fields is summarized. [ABSTRACT FROM AUTHOR]

Abstract The role of nuclear data for neutronics analyses of Fusion Technology (FT) facilities is presented in this paper. Nuclear data evaluations of high quality are required for transport simulations, uncertainty assessments, activation and radiation damage calculations affecting the design and performance of the FT facilities, as well as safety, licensing, waste management and decommissioning issues. A corresponding programme on the nuclear data development (NDD) and qualification is conducted within the Power Plant Physics and Technology (PPPT) programme of EUROfusion supporting the development of the DEMO fusion power plant and the IFMIF-DONES neutron source. The programme builds on the achievements of pre-ceding NDD activities within the European fusion programme as addressed in the paper. Further needs for design, shielding, activation and radiation dose calculations are discussed, and recommendations are given to further improve and qualify the nuclear data base for PPPT nuclear analyses. This includes dedicated experimental activities tailored to the needs of DEMO and IFMIF-DONES. [ABSTRACT FROM AUTHOR]

[Display omitted] • Integration of reduction of dusts and preparation of porous carbon material. • Coupling mechanism between the coal and Zn-bearing dusts was clarified. • K, Na-embedded porous carbon material exhibited good NO adsorption capacity. • K and Na on porous carbon material promoted the chemisorption process of NO. • The solid waste was utilized to treat the NO-bearing flue gas. The increasingly generation of NO-containing flue gases and zinc-bearing dusts has posed huge pressure to the environment. A green process of integration of reduction of zinc-bearing dusts and preparation of porous carbon material with high NO adsorption capacity was developed and its mechanism was clarified in this paper. The reduced dusts with high content of iron (70.52 %) and low contents of harmful elements (0.017 % Zn, 0.015 % K and 0.026 % Na) could be used as high-quality raw material for ironmaking while the K, Na-embedded porous carbon material (APC) with surface area of 390.38 m2/g can be used as effective adsorbent for NO pollution control. The adsorption property and mechanism of NO on APC was investigated. It was found that the maximal removal rate of NO could reach 96.15 %, and the K, Na on porous carbon material could promote the chemisorption process of NO and increase the NO adsorption efficiency of APC. The hazardous waste was successfully utilized to treat the flue gas in this work. [ABSTRACT FROM AUTHOR]

Millions of tons of cotton textile waste are generated annually worldwide, and most of it enters the municipal solid waste (MSW) stream for landfill or incineration disposal, resulting in a significant waste of resources and environmental pollution. This article developed an innovative low-temperature pyrolysis process for producing artificial humic acid (HA) from waste cotton textiles. Subsequently, Al3+ was introduced for a secondary pyrolysis to prepare an Al-doped biochar (Al/BC) with superior adsorption properties. The experimental results show that the presence of Al3+ has an important influence on the pyrolysis process of cotton fabric and the formation and structure of Al/BC. This is the first time to synthesize low-cost adsorbent by pyrolysis and aluminum mixing process of waste cotton cloth and explains the mechanism. This increased in defects (I D / I G = 0.76 to I D / I G = 0.92), a larger specific surface area (6.47 m2/g to 566.94 m2/g), and an increase in oxygen-containing functional groups (from none to C-O-C, O C-O, etc.) when compared to the undoped Al3+ biochar. The optimum Al3+-doped biochar (Al/BC-15) prepared with HA as a precursor exhibited a superior adsorption capacity for Cr(VI) of up to 176.23 mg/g, surpassing the results reported for similar materials in the literature. The adsorption mechanism of Cr(VI) is primarily based on physical adsorption, with some chemical adsorption. At a lower pH, the Al/BC-15 surface exhibits a high positive charge (46 mV). The Al3+-O-Cr(VI) association group is formed through rapid electrostatic attraction between C-Al and Cr(VI). Due to the strong positive electronegativity of Al3+ and the negative electronegativity of C in the vicinity of Al, Cr(VI) is further reduced to Cr(III) by C-Al. Therefore, the method proposed in this paper for preparing Al-doped carbon materials from waste cotton fabric offers a new approach and potential application for the production of high-performance adsorbent materials from waste cotton fabric. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigated age related changes in the EEG of normal children in an eyes-open condition, in order to provide developmental norms for the study of children and adolescents with Attention-Deficit/Hyperactivity Disorder (AD/HD) – see our companion paper (Mason et al., submitted). EEG was recorded at 17 sites from 75 children (63 boys and 12 girls, in the approximately 5:1 ratio common in AD/HD) between the ages of 5 and 16 years. They comprised three groups, each of 25 children (21 boys and 4 girls), divided into Young (5–8 years), Middle (9–12 years), and Old (13–16 years). The EEG was recorded during an eyes-open resting condition and Fourier transformed to provide estimates for total power, and absolute and relative power in the delta, theta, alpha and beta bands. Total power and absolute delta, theta, alpha, and beta decreased with increasing age, as did relative delta, while relative alpha increased with increasing age. Changes occurred faster in the posterior regions for total power, absolute theta and alpha, relative theta, and in frontal regions for absolute and relative beta. Some lateral developmental effects differed with band. These results indicate that maturation effects observed in the eyes-open EEG show some similarities to those reported in eyes-closed conditions, although substantial differences are apparent in the maturation of fast wave activity, particularly alpha. The data provide simple age-norms for eyes-open investigations of EEG differences in young clinical groups, particularly AD/HD. They encourage further investigations of the activational effects of this simple eyes-closed/eyes-open manipulation, which may aid understanding of the energetics of behaviour. • Absolute power in all bands decreased with increasing age. • The development of slow wave activity is similar to that found in an eyes-closed resting condition. • Beta activity developed fastest frontally. [ABSTRACT FROM AUTHOR]

Despite many years having passed since it was discovered, FeTi alloys remain one of the most important low-temperature hydrogen storage alloys due to its high capacity, characteristics and low price. However, the main technological issue is its initial activation, which is usually conducted at relatively high temperature and pressure. This paper is the first to show that the complicated process can be replaced by intense movement of the powder or even chunks of alloy under hydrogen pressure without any additional grinding media. The newly discovered process, named self-shearing reactive milling (SSRM), leads to the full hydrogenation of FeTi alloys. The wear of particles, which is caused by their movement, causes the exposure of a fresh active alloy surface that is active enough to absorb hydrogen without any thermal treatment or evacuation. The resultant material, despite simply being strongly stirred, evolves from large chunks to an extremally fine spongy structure containing particle with sizes of tens of nanometers that combine to form large agglomerates. This result is an enormous improvement for the potential use of FeTi alloys and all other AB-type alloys in commercial applications by extraordinarily simplifying hydrogen storage vessels, which will not have to withstand high-temperature and pressure activation. [Display omitted] • FeTi alloy is activated mechanically at room temperature. • The wear of the surface of particles under H 2 leads to spontaneous hydrogenation. • The method can be applied even for big chunks. • No additives are required. • Alloy is fully hydrogenated. [ABSTRACT FROM AUTHOR]

• New experimental data on fragmentation of 300 MeV/u 124-Xe in aluminum target. • Newly introduced activation depth obeys linear dependence on A/Z2 of the fragment. • The activation depth is a fragment-specific attribute of the depth-profile. • The activation depth can substitute the range and support fragment identification. • Main profile-shape categories have been introduced and described. This work is a continuation of a series of publications devoted to the depth-profiling of activity induced by high-energy heavy-ions in selected accelerator-construction materials. An aluminum target in the stacked-foil configuration was irradiated by 300 MeV/u 124Xe ions. Depth-profiles of induced activity of selected nuclides were obtained by gamma-spectroscopy of individual target foils. Special attention was paid to heavy projectile-fragments and their ranges. Main profile-shape categories have been defined to illustrate typical shapes of the measured profiles. A new quantity – an activation depth – has been introduced and its dependence on the fragment atomic and mass number has been found. It is shown that this quantity is fragment-specific and can substitute the range, which is very useful in case of the activation experiments using the stacked-foil targets with depth resolution limited by the foil thickness. Apart from gamma-spectroscopic parameters and fundamental nuclear properties of the nuclides, the activation depth can be used as an additional nuclide-attribute supporting identification of the projectile fragments and verification of the range-calculating computer codes. Although the main attention of this paper is paid to presenting the new experimental results, comparison with supporting simulations with the aid of ATIMA and FLUKA2020 is included, too. [ABSTRACT FROM AUTHOR]

During the operation of proton exchange membrane fuel cell (PEMFC), it always suffers from reversible performance loss caused by the oxidation of platinum catalyst on its electrode, which reduces the electrochemical active surface area. Short circuit method has been found to improve the performance of fuel cells by stripping of oxides and other adsorbed species from platinum, which needs systematical understanding the effective parameters of short circuit method on fuel cell performance. In this paper, the effects of different short circuit activation parameters (duration, interval, cycles, cut-off voltage, operating current) are carefully studied and analyzed during short circuit operations. In addition, the mechanism revealing how relevant parameters influence short circuit activations is deeply analyzed. The results show that five groups of activation parameters have obvious influence on the activation of fuel cell, indicating that the short-circuit activation effect can be optimized. Among these parameters, the short-circuit duration parameter have the greatest impact on activation, because the platinum hydroxides and oxides is gradually removed during short-circuit duration and results in a larger effective surface area of the platinum catalyst for the electrochemical reaction. However, the smallest impact is short-circuit interval. Another finding is that the five activation parameters are not independent, so the optimal activation parameter value needs to be analyzed in combination with the operating conditions. Finally, according to the activation principle, selection of appropriate short circuit activation parameters for application are proposed to further improve performance and fuel utilization by considering the safety of the stack. • Systematic analysis the effect of short circuit activation parameter on fuel cell. • Comprehensive analysis of activation mechanism of five activation parameters. • The duration parameter improvement rate is about 5%–10% with the greatest effect. • The interval parameter is even negatively related with activation. [ABSTRACT FROM AUTHOR]

Sodium percarbonate (SPC) and peroxymonocarbonate (PMC) have been widely used in modified Fenton reactions because of their multiple superior features, such as a wide pH range and environmental friendliness. This broad review is intended to provide the fundamental information, status and progress of SPC and PMC based decontamination technologies according to the peer-reviewed papers in the last two decades. Both SPC and PMC can directly decompose various pollutants. The degradation efficiency will be enhanced and the target contaminants will be expanded after the activation of SPC and PMC. The most commonly used catalysts for SPC activation are iron compounds while cobalt compositions are applied to activate PMC in homogenous and heterogeneous catalytical systems. The generation and participation of hydroxyl, superoxide and/or carbonate radicals are involved in the activated SPC and PMC system. The reductive radicals, such as carbon dioxide and hydroxyethyl radicals, can be generated when formic acid or methanol is added in the Fe(II)/SPC system, which can reduce target contaminants. SPC can also be activated by energy, tetraacetylethylenediamine, ozone and buffered alkaline to generate different reactive radicals for pollutant decomposition. The SPC and activated SPC have been assessed for application in-situ chemical oxidation and sludge dewatering treatment. The challenges and prospects of SPC and PMC based decontamination technologies are also addressed in the last section. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper discusses the effect of AB 2 (Ti(Cr, Fe) 2) phase on the hydrogenation properties of a Ti–Fe–Cr alloy system. Five Ti–Fe–Cr based alloys were fabricated by varying the Cr content. The microstructural analysis results revealed that the fraction of the Ti(Cr, Fe) 2 phase increased with the increasing Cr content. The first hydrogenation test results indicated that all the alloys could absorb a significant amount of hydrogen at room temperature (30 °C) without a separate activation process. This behavior improved when the Ti(Cr, Fe) 2 phase existed in the AB phase; the kinetics of the first hydrogenation tended to increase with the fraction of Ti(Cr, Fe) 2 phase. The enhancement in the first hydrogenation kinetics of the Ti–Fe–Cr based alloys was attributed to the synergetic effect of the interface between the AB and Ti(Cr, Fe) 2 phases and the inherent fast hydrogenation of the Ti(Cr, Fe) 2 phase. However, the total hydrogen storage capacity decreased when the fraction of Ti(Cr, Fe) 2 phase increased. • AB single phase with Cr is hydrogenated at 30 °C without activation heat treatment. • Hydrogenation kinetics improves as the fraction of the AB 2 phase increases. • The interface between the AB and AB 2 phases also improves hydrogenation kinetics. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO and ZnS catalyse activation of spent tyre pyrolysis char in CO 2. • ZnO-loaded char has higher BET surface area than acid washed char at 950 °C. • Carboreduction of ZnO by char to form Zn vapour and CO increases burn-off. • ZnS dissociates above 600 °C to Zn and S, where Zn reacts with CO 2 to reform ZnO. Utilisation and minimisation of spent tyre stockpiles has been made more viable by pyrolysis and activation to produce low-cost activated carbons. The unique chemical composition of spent tyre pyrolysis chars (STPC), particularly the high Zn content, has been shown to affect their activation and subsequent utilisation. Nonetheless, little research has examined exactly how these additives affect activation and, ultimately, what becomes of Zn during the activation process. This paper presents a systematic study of the effect of Zn, ZnO and ZnS on the physical properties of STPC and their transformation mechanisms during CO 2 activation. Samples of acid-washed STPC with and without ZnO and ZnS addition were activated using a fixed-bed reactor in 66.7% v/v CO 2 for 3 h at 850, 950, 1000 and 1050 °C. Under these conditions, both ZnO and ZnS were found to act as a catalyst during activation, increasing surface area, pore volume and burn-off. During the activation, ZnO was reduced by C to form elemental Zn and ZnS was thermally decomposed to release Zn and S. Thermogravimetric analysis of Zn and its compounds above 600 °C, separately and mixed with acid-washed char, under CO 2 confirms that ZnO and ZnS dissociate to release Zn(v) that further reacts with CO 2 or S to reform ZnO or ZnS. However, Zn is progressively removed from activated carbon at temperatures between 950 °C and 1050 °C. These results have direct implications for the utilisation of SPTC as a feedstock for activated carbon, and the production of Zn-loaded activated carbons. [ABSTRACT FROM AUTHOR]

• Propose a combined activation procedure reducing time and gas consumption. • Validate effectiveness of the procedure at single-cell and stack level. • Reveal change of electrochemical factors and microstructure in activation. • Activation performance is related to hydration status and oxide reduction. Activation is a crucial procedure to improve the performance of newly fabricated fuel cell stacks to meet the power requirements in actual application scenarios. However, traditional activation procedures generally last for several hours or even days, which greatly increases the cost and limits the production efficiency. In response to this problem, this paper proposes a rapid activation procedure composed of hydrogen pumping (HP) and limiting-current activation with limited air (LCA). The influence of current density for HP and air supply for LCA on activation effect is studied and the best operating conditions are determined. The importance of water supply to the cathode is highlighted during HP. The influence of air supply for LCA on activation effect is limited, which contributes to gas saving. According to the experiments conducted on a single cell and a 10-cell stack, only 40 min are needed with this combined procedure, which is much shorter than that of the traditional step-current activation. Furthermore, nearly 75% of hydrogen is saved due to the short activation time and the control of gas supply, thus significantly reducing the cost during activation. Furthermore, to reveal the underlying mechanisms, membrane electrode assembly parameters before and after activation are obtained by micro-current excitation. A decrease in ohmic resistance and an increase in roughness factor of catalyst are observed, which contribute to performance improvement. According to the characterizations in the microstructure of membrane electrode assembly and platinum catalyst valence state, the electrolyte hydration and oxide reduction are determined as key factors and principles during activation. [ABSTRACT FROM AUTHOR]

A large number of materials exist which have been labeled as low activation structural materials (LAM). Most often, these materials have been designed in order to substitute-out or completely remove elements that become activated and contribute significantly to shut-down activity after being irradiated by neutrons in a reactor environment. To date, one of the fundamental principles from which LAMs have been developed is that natural elemental compositions are the building blocks of LAMs. Thus, elements such as Co, Al, Ni, Mo, Nb, N and Cu that produce long-lived decay products are significantly reduced or removed from the LAM composition. These elements have an important part to play in the composition of steels and the removal/substitution can have a negative impact on materials properties such as yield stress and fracture toughness. This paper looks in more detail at whether using isotopic selection of the more mechanically desirable, but prohibited due to activation, elements can improve matters. In particular, this paper focuses on the activation of Eurofer. Carefully chosen isotopically enriched elements, which are normally considered to be on the prohibited element list, are added to EUROFER steel as potential alloying elements. The EUROFER activation results show that some prohibited elements can be used as alloying elements in LAM steels, providing the selected isotopes do not have a significant impact on waste disposal rating or shut-down dose. The economic implications of isotopically enriching elements and the potential implications for decommissioning are considered. It is shown that the addition of molybdenum and nickel in small concentrations (<2% mass) could have the potential to increase availability to such an extent that the capital investment associated with isotope enrichment is negated and profits from electricity sale increased. Another important issue for materials exposed to neutron irradiation is the production of gases, in particular helium, as a result of nuclear interactions. Helium accumulation in materials can cause embrittlement and so mitigating the rate of production is an important consideration when selecting materials. The second part of this paper considers whether helium production can be reduced in CuCrZr by isotopic tailoring. CuCrZr is a candidate bonding material for tungsten at first wall locations, however it suffers from degradation due to helium production. Inventory calculations show that isotopically enriching the copper, in CuCrZr, can reduce helium production by approximately 50%. However, cost–benefit analysis suggests that the cost of enriching copper is not cost-effective due to the high price of electromagnetic enrichment that is required for copper. [ABSTRACT FROM AUTHOR]

• All-sputtered solar cell can be a promising solution to reduce production costs. • Sputtered CdTe is more sensitive to the typical activation treatments. • Increase in CdTe stress was detected after N2-O2-CHClF2 activation. • CdS-CdTe intermix in all-sputtered cells is more extensive than baseline cells. • In this paper an efficiency of 12% in all-sputtered CdTe solar cells was achieved. CdTe thin film solar cells are usually fabricated depositing the absorber layer by Close Space Sublimation (CSS) and Vapor Transport Deposition (VTD), mainly due to the high deposition rate allowed by these techniques. However, most of the solar cell films can be deposited by sputtering, making to deposit also the CdTe by this technique attractive. Indeed, an all-sputtered solar cell could be deposited in one sequential chamber at a relatively low temperature and without breaking the vacuum, resulting in a sensible decrease in the production cost at the industrial level. Usually, treatments based on CdCl 2 , also known as activations, are applied to the CdTe solar cells to achieve high power conversion efficiency (PCE). However, it was observed that the usual activation methods could be aggressive for all-sputtered CdTe solar cells, damaging the films and resulting in low performance. In this work, we propose a novel activation method based on Nitrogen/Oxygen/CHCIF 2 gas mixture, which is more suitable for this kind of device. Morphological, structural, optical and electrical properties were analyzed and compared to our CSS-CdCl 2 baseline. A PCE of 12% was achieved for all-sputtered CdTe solar cells. [ABSTRACT FROM AUTHOR]

The surfaces of the tungsten-coated diamonds have a lot of defects and can be successfully coated by Cu particles by using eletroless plating without sensitization and activation. This process is not only simple, but also obtains a strong interface force between diamond and copper. • Electroless plating of Cu was performed with no need of sensitization and activation. • An interlayer was introduced between diamond and Cu coating. • There exist WC, W 2 C, W in the interlayer between the Cu coating and diamond. • The interlayer enhances the combination between diamond and Cu layer. Conventional electroless plating of copper on diamond particles needs SnCl 2 sensitization and PdCl 2 activation pretreatments, which needs noble metal and consumes a large amount of reducing agent. In this paper, metallic tungsten coatings were first plated onto diamond particles by microwave-heating salt-bath plating (MHSBP) method, and then copper layer was directly plated onto the out surface of the tungsten layer by an electroless plating method with no need of SnCl 2 sensitization and PdCl 2 activation pretreatments. Composition and morphology of the coatings was analyzed by XRD, SEM, and EDS. The results show that the copper coating on the diamond surfaces can be adjusted by control the concentration of CuSO 4 ·5H 2 O and plating temperature, and a full copper coating is achieved with content of CuSO 4 ·5H 2 O of 19.6 g/L in the plating solution at 60 °C. The bending strength of the coated diamond/Cu composites is as high as 630 MPa, which increases 93.3% than the uncoated composites. This work presents an electroless plating of copper can directly on the surfaces of diamond particles with no need of conventional sensitization and activation, and a strong interface combination between coated diamond and copper. [ABSTRACT FROM AUTHOR]

• Quarry sludge can be used as a siliceous material for autoclaved bricks preparation. • Ca(OH) 2 is an ideal calcium source for producing press-moulding quarry sludge-based autoclaved bricks. • The dissolution of SiO 2 in quarry sludge can be optimized by adjusting autoclaved parameters. • The optimum parameters are 200 °C of curing temperature, theoretical Ca/Si ratio of 0.83, and 15 h of exposing time. Quarry sludge (QS) is a common by-product of quarry mining and the subsequent aggregate washing process, but its utilization in construction materials was limited by fine particle size and high crystallization. This paper assesses the feasibility of reusing QS as siliceous materials to prepare a novel eco-friendly brick via press moulding and autoclave treatment. Three types of calcium sources including CaO, Ca(OH) 2 , and CaCO 3 were employed to evaluate the binding efficiency with QS by using X-ray diffraction (XRD), thermogravimetry and differential scanning calorimetry (TG-DSC) and scanning electron microscopy (SEM). The effect of curing temperature, Ca/Si ratio and exposing time on the reaction activity of QS were estimated, and their roles on the microstructure and compressive strength of QS-based bricks were evaluated. Results demonstrate that the activity of QS can be effectively activated by Ca(OH) 2. The morphology of the curing phases is determined by the dosage of QS. Moderating curing temperature (160 °C to 200 °C) and exposing time (≤15 h) contribute to higher reaction activity of QS and favor the generation of plate-like tobermorite and C-S-H, which induced a denser structure of QS-based autoclaved bricks and further promoted the strength development. In addition, 24 h of exposing time induced the transformation from tobermorite to xonotlite, prejudicing the strength of QS-based autoclaved bricks. Considering the performance and energy consumption, the optimum manufacturing parameters of QS-based autoclaved bricks are curing at 200 °C for 15 h, with a Ca/Si ratio of 0.83. Under this treatment, the compressive strength of QS-based autoclaved brick is as high as 49.9 MPa with a QS dosage of 63.5%. In addition, an assessment of the mobility of heavy metals associated with QS-prepared bricks reveals that autoclaved treatment can solidify heavy metals and QS-based autoclaved bricks can be regarded as an environmentally friendly building product. This research provides a foundational framework for the efficient utilization of QS through hydrothermal activation. [ABSTRACT FROM AUTHOR]

An experiment was carried out in June 2018 at CERN in order to benchmark FLUKA and ActiWiz activation calculations with experimental data. A first set of samples made of Copper, Aluminium, Stainless Steel and Kovar with a well-known elemental composition was irradiated by the direct impact of a mixed hadron beam of the CERF facility with a momentum 120 GeV/ c. A second set of samples was located downstream of a 50 cm long copper target and irradiated by the secondary particles generated from this impact. This paper discusses first the experimental results obtained by γ -spectrometry measurements after 30 days of cooling time for the two set of samples. Then, it discusses the FLUKA simulations performed in order to get the radionuclide inventory as well as the mixed particle fluence spectra in the samples for the two positions. In a third part, it discusses the predictions given by the ActiWiz software compared with the FLUKA results. Finally, the experimental and theoretical results are compared and discussed. [ABSTRACT FROM AUTHOR]

• ANITA-NC is a code system, developed in ENEA-Bologna, able to treat the activation induced by neutral and charged particles. • ANITA-NC uses EAF-2010 activation cross section libraries for neutrons, deuterons and protons. • A new neutron activation cross section library in EAF format was produced based on TENDL-2017 evaluated data. • Some application examples of neutron, deuteron and proton activation are shown. • A good agreement between ANITA-NC and FISPACT-II results is found. ANITA-NC (Analysis of Neutron Induced Transmutation and Activation – Neutral and Charged) is an inventory system (code and libraries) developed in ENEA-Bologna, capable of modelling material activation induced by neutral or charged projectiles (i.e. neutrons, protons, deuterons, alphas or gammas). It is an extension of the previous ANITA versions. ANITA-NC requires group-wise activation cross-section libraries in EAF format. It actually uses the most recent libraries in this format, that is the EAF-2010 libraries in the VITAMIN-J+ (211) energy group structure, up to 55 MeV. For neutrons, a new library in a 271 energy group structure up to 200 MeV, based on TENDL-2017, was produced. The decay data used in ANITA-NC are based on the JEFF-3.1.1 Radioactive Decay Data Library. This paper summarizes the main characteristics of the ANITA-NC activation system. Some application cases and an example of data and code validation on experimental results are shown. [ABSTRACT FROM AUTHOR]

• Activated and deactivated bed material particles have different distributions of K. • Potassium-rich layer was found around the particles after activation. • The leachable K fraction (K 2 O/KOH) correlates with activation of the bed material. • K 2 SiO 3 is the dominant K-containing species within the particles upon deactivation. The GoBiGas plant, which comprises a 32-MW th dual fluidized bed gasifier, was constructed as a demonstration unit for converting biomass to biomethane via gasification. On several occasions during the commissioning of the plant, low activity of the olivine bed generated a high content of tar in the produced gas, which was deleterious to the downstream equipment. The problem was attributed to a deficiency of ash constituents, and the solution was to control activation of the bed material through the addition of K 2 CO 3 to the process. This enabled extended operational periods without tar-related issues. The achieved activity could be lost during interrupted operation at which time the activation procedure had to be repeated. In the present paper analysis of the bed material samples extracted upon activation and after loss of activity using Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy (SEM-EDS) showed similar morphologies for the ash layers formed around the olivine particles. The observed differences mainly related to the distributions of potassium (K) across the layers. Furthermore, surface analysis showed differences in K speciation within the outer regions. K solubility tests and X-ray photoelectron spectroscopy analyses indicated that K was present as an oxide/hydroxide rather than as a silicate on the surface of the active olivine. The presented results are of major relevance for the operation of dual fluidized bed gasifiers with fuels that are potassium-lean when ash components need to be supplied as additives. [ABSTRACT FROM AUTHOR]

Highlights • Systemic activation analysis of FLiBe has been firstly carried out for the molten salt reactor. • The activation analysis was carried out based on an actual reactor design, TMSR-SF1. • The nuclides for shielding design, occupational exposure and environment have been studied. • The initial impurities and corrosion products during operation have both been considered. Abstract As an excellent material for candidate coolant of the molten salt reactor, the activation of 2LiF-BeF 2 is an important issue and should be concerned. In this paper, the activation of 2LiF-BeF 2 has been analyzed based on a specific Molten Salt Reactor. And combined approaches, Monte Carlo method for neutron transport and extension of the Euler for inventory calculation, have been adopted. The short life nuclides for shielding design, the long-life nuclides for occupational radiation exposure management and 3H, 14C production for environment protection have been studied. [ABSTRACT FROM AUTHOR]

• Effect of activation method on MEA durability is studied. • Activation procedure has an irreversible effect on MEA performance and durability. • Faster performance drop is achieved using constant current activation method. • More severe platinum agglomeration is seen using constant current activation method. • Constant low current density procedure is not an efficient activation method. In this paper, the influence of activation procedure on the long-term performance of membrane electrode assembly (MEA) is investigated. The MEAs are activated by most commonly used procedures; constant voltage and constant current. After activation, MEAs are implemented under 9000 aging cycles. During aging process, MEAs performance is evaluated using polarization curves, electrochemical impedance spectroscopy and cyclic voltammetry. The obtained results show that the activated MEA by constant current method shows an average voltage decay of 11.33 µV/cycle at 1 A/cm2, compared to 4.4 µV/cycle for the activated MEA by constant voltage procedure. This is due to the more reduction of electrochemical surface area for the activated MEA by constant current method (32% vs. 19%). Also, after 9000 degradation cycles, more severe platinum nanoparticles agglomeration is seen in the cathode catalyst layer of activated MEA by constant current procedure. This shows that MEA activation by constant current activation method not only need to the longer activation time, but also causes higher catalyst layer degradation. [ABSTRACT FROM AUTHOR]

Abstract The fly ash from the Corner Brook Pulp and Paper (CBPP) mill was used in this study as the raw material for the preparation of a low-cost adsorbent for arsenic removal from the well water of Bell Island. The CBPP fly ash was physically activated in two different ways: (a) activation with pure CO 2 (CAC) with the iodine number and methylene value of 704.53 mg/g and 292.32 mg/g, respectively; and (b) activation with a mixture of CO 2 and steam (CSAC) with the iodine number and methylene value of 1119.98 mg/g and 358.95 mg/g, respectively, at the optimized temperature of 850 °C and the time of 2 h for both activations. The BET surface areas of the CAC and CSAC at the optimized conditions were 847.26 m2/g and 1146.25 m2/g, respectively. The optimized CSAC was used for impregnation with iron (III) chloride (FeCl 3) with different concentrations (0.01 M to 1 M). The study shows that the adsorbent impregnated with 0.1 M FeCl 3 is the most efficient adsorbent for arsenic removal. Isotherm analysis shows that the Langmuir model better describes the equilibrium behavior of the arsenic adsorption from both local well water and synthesized water compared to the other models. The maximum arsenic adsorption capacity was 35.6 μg/g of carbon for local well water and 1428.6 μg/g of carbon for synthesized water. Furthermore, the kinetic behavior of arsenic adsorption from synthesized and local well water was well depicted by the pseudo-second order kinetic model. Graphical abstract Unlabelled Image Highlights • Higher surface and pore volume achieved through the activation with the mixture of steam and CO 2 • Iron impregnation of the adsorbent significantly increases the removal efficiency of arsenic. • Langmuir model better describes the equilibrium behavior of arsenic adsorption. [ABSTRACT FROM AUTHOR]

Abstract Although written corrective feedback (WCF) is often believed to evoke negative emotions, empirical studies on L2 students' affective reactions to this teaching and learning device are still lacking. Informed by research on academic emotions (Pekrun, 2006; Pekrun & Linnenbrink-Garcia, 2012), the paper reports on two case studies investigating Chinese university EFL students' emotional reactions to teacher WCF. Self-report data collected from retrospective verbal reports and interviews constituted most of the data, supplemented by observation notes, student writing, and class documents. Qualitative data analysis revealed the richness and dynamicity of the focal students' emotional reactions to WCF. While both students reported being emotionally undisturbed by WCF, they in fact experienced different discrete emotions with varying object foci, valence, and activation, and these emotions fluctuated in the revision process. The findings question the presumed connection between WCF and negative emotions, suggesting the inadequacy of the positive-negative distinction of emotions and the need for a more nuanced understanding of emotional reactions to feedback. [ABSTRACT FROM AUTHOR]

Graphical abstract Lead ions mainly increase the active sites on scheelite surface to improve the adsorption amount of NaOL, thus improving the floatability of scheelite. The adsorption coverage of NaOL on the surface of scheelite increase significantly, but it does not affect the adsorption layer thickness of NaOL (still 6 nm–7 nm), the adsorption form is still multilayer adsorption. Highlights • Lead ions can significantly improve the floatability of scheelite in NaOL system. • Lead ions increase the adsorption amount of NaOL on scheelite surface by adsorption mechanism analysis. • Lead ions mainly increase the active sites on scheelite surface to improve the floatability. • Lead ions mainly increase the NaOL adsorption coverage rather than the adsorption thickness by AFM study. • An adsorption model is finally obtained. Abstract This paper systematically studied the effect of lead ions on floatability of scheelite under sodium oleate (NaOL) system, and the deep adsorption mechanism was revealed by a series of mechanism experiments and the adsorption morphology of NaOL was observed by atomic force microscope (AFM). Micro-flotation test indicated that the floatability of scheelite increased sharply from 47.25% to 80.12% in the presence of lead ions at pH 7. Zeta potential results revealed the positively charged lead ions species (Pb2+ and PbOH+) positively changed the zeta potential of scheelite, which favored the adsorption of negatively charged NaOL species (RCOO−, RCOOH·RCOO− etc.). XPS and FTIR analysis confirmed that NaOL was chemisorbed on scheelite surface and the adsorption was more severe in the presence of lead ions. Lead ions were chemisorbed on scheelite surface in the form of W-O-Pb2+, which facilitated the further adsorption of NaOL. This increased the active sites on scheelite surface for NaOL adsorption. AFM images intuitively showed the presence of lead ions increased the adsorption coverage of NaOL but did not affect the thickness of the adsorption layer. The adsorption thickness was still 6 nm–7 nm and the adsorption was multilayer adsorption. Based on these studies, an adsorption model was finally obtained. [ABSTRACT FROM AUTHOR]

Abstract The emergence of resistance to antibacterial drugs and pesticides in water is unprecedented. This may have adverse consequences to human health and ecological systems. This paper first sought the identification of a wide range of pharmaceuticals and pesticides in two secondary effluent wastewaters (SEW) of different quality characteristics, followed by their removal by ferrate(VI) (Fe(VI), FeO 4 2−). Screening for 22 pharmaceuticals and 32 pesticides, revealed that 11 pharmaceuticals and 3 pesticides in SEW of plant A, and 14 pharmaceuticals and 5 pesticides in SEW of plant B were present at concentrations higher than the liquid chromatography mass spectrometry method quantitation limit. The concentrations of pharmaceuticals and pesticides ranged from 0.15 ng/L-413.03 ng/L. Investigation of the removal of these pharmaceuticals and pesticides by Fe(VI) showed that some had recalcitrant activity towards their oxidation. Acid-activated Fe(VI) resulted in enhanced oxidation (12.6%–56.2% degradation efficiency) of 6 and 7 pharmaceuticals in SEW of plant A and plant B, respectively, at a shorter time than Fe(VI) without activation (i.e. 3–5 min versus 15–30 min). The degradation of 1 and 3 pesticides in SEW of plant A and plant B respectively, has also been enhanced by activating Fe(VI) (13.8%–86.2% degradation efficiency). Results on testing of organic matter characterization of treated SEW with and without acid-activated Fe(VI) treatment are also presented. Acid-activated Fe(VI) treatment has potential in enhancing the removal of micropollutants in real wastewater. Graphical abstract Image 1 Highlights • Pharmaceuticals and pesticides were screened in two secondary effluent wastewaters. • Fe(VI) successfully removed a wide range of pollutants in wastewaters. • Acid-activated Fe(VI) could enhance removal of recalcitrant pollutants. • Removal by acid-activated Fe(VI) occurred at shorter time than nonactivated Fe(VI). • Acid-activated Fe(VI) decreased organic contents of secondary effluent wastewaters. [ABSTRACT FROM AUTHOR]

Highlights • Prestressed iron-based shape memory alloy system for retrofitting steel plates. • Development of a mechanical anchorage system for SMA-to-steel joints. • Activation of Fe-SMA strips by electrical heating up to 260 °C. • Recovery stress generation under different elastic restraint conditions. Abstract This paper presents the development of an iron-based shape memory alloy (Fe-SMA) system for the strengthening of steel plates. The shape memory effect (SME), which is the tendency of a deformed SMA to return to its original shape upon heating and subsequent cooling, was used in this study for prestressing steel plates. Five steel specimens were strengthened with different configurations (single-side, double-side, activated, and non-activated) of the Fe-SMA strips. A mechanical anchorage system was developed to anchor the prestressed Fe-SMA strips to the steel substrate. The SME in the Fe-SMA strips was then activated (i.e., the strips were prestressed) by heating to a temperature of approximately 260 °C using an electrical resistive heating technique. The test results showed that the achieved recovery stress of the Fe-SMA strips (i.e., the prestressing level after activation) was approximately in the range of 350–400 MPa, which led to a maximum compressive stress of −74 MPa in the steel plate. This compressive stress can be very beneficial and significantly increase the yield and fatigue strength of the steel plates. Finally, the strengthened specimens were subjected to static loading under a displacement-controlled condition up to failure. It was shown that the proposed strengthening technique eliminates the difficulties associated with conventional prestressing (e.g., by hydraulic jacks) and also offers a fast installation procedure as it does not require any surface preparation or curing for bond application. [ABSTRACT FROM AUTHOR]

Abstract Accurate measurement of the nuclear environment within a test tritium breeding-blanket module of a fusion reactor is crucial to determine tritium production rates which are relevant to self-sufficiency of tritium fuel supply, tritium accountancy and also to the evaluation of localised power levels produced in blankets. This requires evaluation of the time-dependent spectral neutron flux within the test tritium breeding-blanket module under harsh radiation and temperature environments. The application of an activation foil-based spectrometer system to determine neutron flux density using a pneumatic transfer system in ITER has been studied, deployed and tested on the Joint European Torus (JET) machine in a recent deuterium - deuterium campaign for a selection of high purity activation foils. Deployment of the spectrometer system has provided important functional and practical testing of the detector measurement system, associated hardware and post processing techniques for the analysis of large data sets produced through the use of list mode data collection. The testing is invaluable for the optimisation of systems for future planned testing in tritium - tritium and deuterium - tritium conditions. Analysis of the time and energy spectra collected to date and the status of the development of methods for post-processing are presented in this paper. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents the results of a study on obtaining N-enriched active carbons from bituminous coal and on testing its use as an electrode material in supercapacitors. The coal was carbonised, activated with KOH and ammoxidised by a mixture of ammonia and air at the ratio 1:3 at 300°C or 350°C, at different stages of the production, that is, at those of precursor, carbonisate, and active carbon. The products were microporous N-enriched active carbon samples of well-developed surface area reaching from 1577 to 2510m2/g and containing 1.0 to 8.5wt% of nitrogen. The XPS measurements have shown that in the active carbons enriched in nitrogen at the stage of precursor and at the stage of carbonisate, the dominant nitrogen species are the N-5 groups, while in the samples ammoxidised at the last stage of the treatment the dominant nitrogen species are the surface groups of imines and/or nitriles, probably accompanied by amines and amides. The paper reports the results of a comprehensive study of the effect of the structure and chemical composition of a series of active carbon samples of different properties on their capacity performance in water solutions of H2SO4 or KOH, with the behaviour of positive and negative electrodes analysed separately. [ABSTRACT FROM AUTHOR]

Abstract: In the processing of sulphide ores, there is generally a concentration step such as flotation, before smelting. One of the problems arising in the smelter is the presence of ‘MgO’ and one of the major challenges in the flotation step is to reduce the amount of ‘MgO’ recovered to the concentrate and thus reporting to the smelter. The reporting of ‘MgO’ in concentrates is a pseudo-representation of the range of actual magnesium-bearing minerals which are present in the ore and concentrator products. However, since the total amount of ‘MgO’ present in a concentrate is what drives the smelting problem, regardless of which mineral source, the ‘MgO’ content is the measurement of interest. One of the major sources of MgO is pyroxene, and particularly orthopyroxene. The common occurrence of talc, which also bears MgO, in association with orthopyroxene, warrants additional focus on this mineral. This paper reviews the occurrences of pyroxene and talc in sulphide ore bodies, focussing on the Merensky ore in South Africa and the Sudbury ores in Canada. The various mechanisms by which it reports to the concentrate and methods of reducing these mechanisms, are discussed. Four mechanisms have been identified and each of these has a different treatment route – that are quite wide ranging in effort and cost This paper shows the importance of identifying the mechanisms involved so that the correct treatment can be used. The incorrect treatment can prove costly but in many cases ineffective – a principle of project management that is wider than this paper alone. It also shows the valuable contribution that quantitative mineralogy/process mineralogy makes to process diagnosis and optimisation. [Copyright &y& Elsevier]

Abstract: Investigation of current and planned fusion devices, as well as conceptual power plants, requires well-validated tools to predict the activation of materials. This has led to the production of the European Activation System (EASY), which provides such a capability. The version used here, EASY-2003, is widely distributed and has been used to carry out activation calculations on a large number of materials. However, there was also a need for a comprehensive handbook of activation data that could be quickly referred to, rather than resorting to running codes. This paper discusses the process of generating, over a period of 8 months, the data for a handbook that presents the important activation data for all the naturally occurring elements from hydrogen to uranium. The main computational methods are outlined briefly, but the bulk of the paper is focused toward a description of the different ways in which the data are presented, including new presentations of activation data, called ‘importance diagrams’. [Copyright &y& Elsevier]

Abstract: The present paper is the continuation of a previous work dealing with the activation of anthracites with NaOH at various temperatures, ranging from 600 to 830°C [A. Perrin et al., Carbon 42 (2004) 2855]. In this latter article, the pore textures were accurately investigated through the adsorption isotherms of four probe molecules characterised by their increasing molecular diameters, namely CO2, N2, C6H6 and CCl4, and the methane storage capacities were measured and discussed accordingly. In the present paper, the same kind of study is carried on, keeping the activation temperature constant at 730°C (which was previously found to lead to the highest density of adsorbed methane), but changing the mass ratio NaOH/anthracite, R, from 1 to 3. The changes occurring for each kind of pores and the specific volumes of different micro- and meso-pore families are measured and discussed. Just like in our previous work, two separate mechanisms of porosity development are evidenced. Mass ratios NaOH/anthracite R ⩽2 mainly lead to the creation of micropores of effective widths close to the optimal value for methane storage, i.e., 0.8nm. While higher values of R mainly lead to the widening of already existing pores. Methane storage isotherms at 20°C were measured up to 3.5MPa for the investigated materials. Linear correlations between various textural parameters and methane storage capacities were given. Additionally, a number of results previously reported in the literature were confirmed by the present work. [Copyright &y& Elsevier]

Abstract: This work presents a macro-level model to determine the performance characteristics of solid oxide fuel cells (SOFCs). Activation, ohmic, and concentration polarizations are considered the main sources of irreversibility. The Butler–Volmer equation, the dusty gas model, and Ohm’s law were used to determine the polarization terms. Tafel equation, linear current potential, Fick’s model, and Stefan–Maxwell model were quantitatively analyzed as well. Performance curves were calculated for hydrogen, methane, and carbon monoxide as pure fuels at different conditions. A surface plot for each polarization term allowed us to analyze the contribution to voltage loss as a function of temperature and current density. The calculations presented in this paper involved the creation of many computational tools. One sample code of these algorithms is included, but all algorithms used in the paper are available from the authors. [Copyright &y& Elsevier]

The proton exchange membrane fuel cell (PEMFC) is an emission-free alternative to the internal combustion engine. Post-assembly, a PEMFC must be "activated', to elevate and stabilize its performance to a reproducible threshold value. This procedure is costly, time-consuming, and not suited for mass-production. This paper provides a detailed review of the break-in physical principles, activation procedures and characterization methods. First, all sparse knowledge from the literature is translated into a set of activation mechanisms. Activating a cell mainly alters the membrane electrode assembly morphology (e.g. catalyst layer porosity, catalyst size, shape and activity, polymer chain orientation). Second, an in-depth analysis off all break-in methods is provided. Cell components can be pre-activated using steam, acid, plasma or through compression. Dynamic, high temperature/pressure and supersaturated operation promote break-in kinetics. Generating oxidizing and reducing conditions is essential, and is achievable by short circuit, Cyclic Voltammetry, cathode starvation or reactant switch. Uniform activation over the cell surface is obtained with gas flow direction reversal or hydrogen pumping. Compression cycles minimize PEMFC contact resistances. Finally, deficiencies of conventional break-in characterization methods (to measure cell performance and impact on durability) are highlighted. Better reproducibility is achievable using advanced electrochemical characterization, post-mortem and cell output species analysis. • Each morphological change associated to PEM fuel cell break-in is detailed. • All ex-situ and in-situ activation methodologies are reviewed. • Break-in characterization methods are studied, and advanced solutions are proposed. • A critical analysis of the current "end-of-break-in" criteria is provided. [ABSTRACT FROM AUTHOR]

• TOF and TON of catalytic systems Ni(acac) 2 –AlEt 3 –amine in the styrene hydrogenation was obtained. • The NR 3 →AlEt 3 adduct formation with nickel-containing sites has been defined. • A model scheme for formed catalytically active site in the presence of an amine was suggested. The paper reports on a possible modification of the multicomponent catalytic system based on Ni(acac) 2 and AlEt 3 by different amines. It is shown that, depending on the nature of the amine, the performance of the modified Ni(acac) 2 –AlEt 3 system is limited only to the size of the reaction vessel. Using various physical-chemical methods, it is found that during the formation of a catalytically active system, the NR 3 →AlEt 3 adducts are produced. The latter, unlike AlEt 3 excess, are not able of poisoning the nickel-containing catalytically active centers. The model of the formation of a catalytically active site in the presence of an amine is proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • High specific surface area of activated carbon was obtained with low burn-off. • Pore structure of samples was affected by reaction rate and diffusion controlling. • Proper limitation of reaction rate was useful for diffusion of steam. • Reaction rate and diffusion of steam were controlled by simple method. In this paper, activation reaction, together with diffusion of activation reagent (H 2 O) through samples, were both controlled during activation process of spherical activated carbon (SAC) by simple methods, pore structure of the obtained SAC was analyzed to show the influence of controlling process. Results showed that proper limitation of reaction rate might give more chance for steam to diffuse through samples, and thus more specific surface area (mainly caused by micropores) could be obtained with less burn-off. Additionally, if the diffusion of steam was limited during activation process, though the pore diameter of SAC could be widened, excessive pore corrosion might lead to high inefficient burn-off and low specific surface area. Further studies indicated that, even using same controlling condition, SAC with different diameters had different pore structure or specific surface area, which could be attributed to difficult diffusion of steam into samples with large sizes. [ABSTRACT FROM AUTHOR]

• 1. Sodium thiocyanate used as activator in flotation process for the first time. • 2. Sodium thiocyanate has a better activation effect on heteromorphite than that of sodium sulfide. • 3. The ambidentate ligand SCN- can chemisorbed on the heteromorphite surface via S or N elements. • 4. After Sodium thiocyanate treatment, zeta potential of the heteromorphite was greatly decreased. • 5. Sodium thiocyanate can enhance the physical adsorption strength of collector ODA on the mineral surface. In this paper, sodium thiocyanate (NaSCN) has been used for the first time as an activator of heteromorphite. In the flotation of heteromorphite, 93% recovery was obtained at the concentration of collector ODA 0.4 × 10–4 mol/L in the presence of NaSCN, while the concentration of collector should be 2.5 × 10–4 mol/L and 0.6 × 10–4 mol/L for the non-activator or Na2S treatment, respectively. The Micro-flotation results showed that heteromorphite can be effectively activated by NaSCN. Nay, the activation effect was better than sodium sulfide, and was slightly affected by activation time. FTIR analysis, Zeta-potential measurements and XPS analysis were conducted to determine the activation mechanism of sodium thiocyanate on heteromorphite. The result of FTIR analysis showed that after NaSCN treatment, the collector ODA can be chemisorbed on the heteromorphite surface via forming zinc-ammonium complex, and physically adsorbed simultaneously by electrostatic attraction. Note that the physisorption effect is more significant. Zeta-potential measurements and XPS analysis showed that the ambidentate ligand SCN− can chemisorbed on the heteromorphite surface via forming zinc-thiocyanate complex anions by S or N elements. What's more, the value of zeta potential of minerals was more negative, which enhanced the physisorption of collector on the mineral surface. Ultimately, the surface hydrophobicity of the heteromorphite was enhanced, and better flotation recovery effect was obtained. The results of this paper can provide a new idea for the activation of minerals. [ABSTRACT FROM AUTHOR]

Activated carbon has been widely used as adsorbents, catalyst support and energy storage materials. Microwave heating is a promising technique for thermochemical treatment and activation of activated carbons due to its fast, selective, uniform and volumetric heating. Previous reviews mainly focused on specific feedstocks (e.g. agricultural biomass or oil palm wastes) or ignored important parameters for microwave activation (e.g. mass of activated carbon precursor). Characteristics of activated carbons prepared from conventional and microwave treatment were not compared and economics of microwave activation were not described in previous studies. This paper presentst a state of the art review of activation under microwave irradiation for various biomass sources (e.g. agricultural wastes, woody biomass and sewage sludge). Characteristics of microwave heating, main activation parameters, research progress and technology status of activated carbon preparation and regeneration under microwave irradiation are investigated with key challenges and economics being addressed. Characteristics of activated carbons made from microwave irradiation and conventional activation are compared and the advantages of microwave-assisted preparation are highlighted. It shows that the BET (Brunauer–Emmett–Teller) surface area, iodine number, methylene blue adsorption capacity and the yield of activated carbons under microwave irradiation are up to 2500–3000 m 2 /g, 1800–2200 mg/g, 500–700 mg/g and 13–96 wt%, respectively, competitive with conventional methods on the quality of activated carbons and process economics. Potential applications and future perspectives are described with pertinent information on activated carbon preparation under microwave irradiation. [ABSTRACT FROM AUTHOR]

Sulfate radical-based advanced oxidation processes (AOPs) have been received increasing attention in recent years due to their high capability and adaptability for the degradation of emerging contaminants. Persulfate (PS, S 2 O 8 2− ) and peroxymonosulfate (PMS, HSO 5 − ) can be activated by thermal, alkaline, ultraviolet light, activated carbon, transition metal (such as Fe 0 , Fe 2+ , Cu 2+ , Co 2+ , Ag + ), ultrasound and hydrogen peroxide to form sulfate radical (SO 4 − ), which is strong oxidant and capable of effectively degrading emerging pollutants. Sulfate radical-based AOPs have a series of advantages in comparison with OH-based methods, for example: higher oxidation potential, higher selectivity and efficiency to oxidize pollutants containing unsaturated bonds or aromatic ring, wider pH range. Therefore, sulfate radicals are capable of removing the emerging contaminants more efficiently. In this review paper, various methods for the activation of PS and PMS were introduced, including, thermal, alkaline, radiation, transition metal ions and metal oxide, carbonaceous-based materials activation and so on; and their possible activation mechanisms were discussed. In addition, the application of activated PS and PMS for the degradation of emerging contaminants and the influencing factors were summarized. Finally, the concluding remarks and perspectives are made for future study on the activation of PS and PMS. This review can provide an overview for the activation and application of PS and PMS for the degradation of emerging contaminants, as well as for the deep understanding of the activation mechanisms of PS and PMS by various methods. [ABSTRACT FROM AUTHOR]

Cellulase and hemicellulase activities in a 1:1 ratio of enzymes extracted from Chrysoporthe cubensis and Penicillium pinophilum were evaluated in the presence of known monocomponent phenolic inhibitors and also with phenol mixtures derived from alkali pretreated sugarcane bagasse. The cellulolytic activities from C. cubensis : P. pinophilum displayed a much higher tolerance to phenolic inhibitors than equivalent enzyme activities obtained from Trichoderma reesei and Aspergillus niger . Enzymes from T. reesei and A. niger were deactivated at 0.3 and 1.5 mg phenols/mg protein, respectively, as reported previously, while enzymes from C. cubensis : P. pinophilum resisted deactivation at 35 mg phenols/mg protein. However, tolerance of xylanase with respect to phenols required the presence of laccase. Removal of laccase (enzyme) activity using sodium azide resulted in a 2x higher xylanase deactivation (from 40% to 80%). This paper identifies enzymes that are phenol tolerant, and whose adoption for lignocellulose hydrolysis could contribute to reductions in enzyme loading needed to hydrolyze alkali pretreated lignocellulosic substrates in the presence of lignin derived phenols. [ABSTRACT FROM AUTHOR]

Electroencephalography (EEG) measures the electrical activity of brain that is generated by the synchronized activity of thousands of neurons. In this paper, our first goal is to develop a novel method to track the EEG activation in different brain regions involved in the processing of target and non-target stimuli in oddball paradigm. Secondly we want to identify the difference in the pattern of activation for different oddball tasks. The EEG data has been acquired from twenty healthy volunteers for the visual oddball experiment. In the task two types of visual stimuli target (rare) and non-target (frequent) were randomly presented. The subjects were instructed to press the enter button when they identify the target stimuli. The EEG data acquired is converted into EEG topo-maps. In our method the flow of activation between consecutive topo-maps is estimated by using Horn and Schunck Optical Flow estimation method. It helps to generate the motion field between consecutive topo-maps which is considered as flow of activation between two time frames. Different motion vectors are clustered into a group based on the activation level. These clusters are tracked between different frames as a measure of the activation flow. Finally we analyze the flow of activation across different brain lobes for different cases encountered in the Oddball paradigm by plotting average activation graph with respect to time. Analysis of the data has revealed that high activation has been observed in the Frontal and Occipital lobes in general for the oddball task. Frontal lobe shows high activation for target with response case, this is followed by the Occipital lobe. The activation in frontal lobe starts increasing from frame no 60 (240 ms) (out of 125 frames). Occipital lobe shows high activation for target with no response and no target no response cases in the region from 40 to 60 frames. Parietal lobe shows high activation for target with response near the end of task from frame no. 100 onwards. Hence, we have been able to identify different patterns in the activation flow that differentiates different Oddball tasks. This activation pattern is consistent with the event related potential signal generated by the Oddball paradigm. The pattern for the individual subjects also follow the average pattern of high activation in the frontal and occipital region for target and non target stimuli. We have also used cross correlation (a classical connectivity method) for comparison of the results. A subjective comparison of the results show that our proposed method is capable of tracking the EEG activation. [ABSTRACT FROM AUTHOR]

Demonstrating tritium self-sufficiency is an important goal of the European tokamak demonstration fusion reactor. Currently four breeder blanket concepts are being considered: the Helium Cooled Pebble Bed (HCPB), Helium Cooled Lithium-Lead (HCLL), Dual Cooled Lithium-Lead (DCLL) and Water Cooled Lithium-Lead (WCLL). Differences in materials and construction of the four breeder blanket concepts lead to differing nuclear responses. As well as affecting tritium breeding this is also of particular importance in safety analyses, such as the modelling of loss of coolant accidents, as it affects the blanket's decay heat and nuclide inventory. This paper presents and discusses analysis performed for each of the 2014 designs of the blanket concepts to ascertain the decay heat and nuclide inventory for the entire reactor. It was found that the total decay heat at short decay times for the HCLL concept (17.5 MW at 1 s) was between 17% and 22% lower than the HCPB, WCLL and DCLL. At longer decay times (∼100 years) it was found that the DCLL and WCLL blankets had decay heats in the region of 2–3 orders of magnitude above the HCPB and HCLL blankets. The differences noted between the blanket concepts are discussed in terms of neutron spectrum and material composition. [ABSTRACT FROM AUTHOR]