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We show theoretically and experimentally how a flat-top second-order response can be achieved with a self-coupled single add-drop ring resonator based on two couplers with different splitting ratios. The resulting device is a 1x1 filter, reflecting light back in the input waveguide at resonating wavelengths in the passbands, and transmitting light in the output waveguide at all other non-resonating wavelengths. Different implementations of the filter have been designed and fabricated on a micron-scale silicon photonics platform. They are based on compact Euler bends - either U-bends or L-bends - and Multi-Mode Interferometers as splitters for the ring resonators. Different finesse values have been achieved by using either 50:50 MMIs in conjunction with 85:15 MMIs or 85:15 MMIs in conjunction with 95:05 double MMIs. Unlike ordinary lowest order directional couplers, the MMIs couple most of the power in the cross-port which make them particularly suitable for the topology of the self-coupled ring, which would otherwise require a waveguide crossing. Experimental results are presented, showing good agreement with simulations. The proposed devices can find applications as wavelength-selective reflectors for relatively broad-band lasers or used as 2x2 add-drop filters when two exact replicas of the device are placed on the arms of a Mach-Zehnder interferometer., 9 pages, 17 references, 12 figures

The ITER Remote Handling Control System (RHCS) controllers provide measurement and diagnostics data about the remote handling equipment and tools they control. This paper presents the Remote Diagnostics Application (RDA) software for the analysis and archiving of the RHCS diagnostics data. The RDA provides a basic set of diagnostics tools, including trends, spectra, histograms, scatter plots, cross-correlation plots, as well as archiving and retrieval of history data. The ITER RH operators can extend diagnostics capabilities for specific RH equipment needs by incorporating custom diagnostics functions. To facilitate customization, RDA implements an architecture with three nested levels: the RDA Framework, its Diagnostics Workbenches and their Diagnostics Primitives. The RDA Framework has a user interface that can load one or several special diagnostics cases implemented as custom Diagnostics Workbenches with custom or default Diagnostics Primitives, such as rules, analysis functions and filters. As a result, the RDA features a diagnostics framework to execute complex and dedicated diagnostics and prognostics for the RH experts to monitor performance data, to run diagnostics tests and rules on equipment systems and to analyse historical data. The RDA helps the RH operators reduce downtime of the Remote Handling systems by exposing failure conditions and maintenance needs.

In-service thermal aging of CF8M cast austenitic stainless steel was investigated in materials removed from the steam generator inlet and crossover elbows of the Ringhals 2 pressurized water reactor nuclear power plant unit after approximately 92kh of full operating time. The thermal aging of these materials was investigated using the double loop electrochemical potentiokinetic reactivation method, coupled with indentation hardness measurements and microstructural characterizations, to identify correlations between the electrochemical behavior and traditional methods of investigating thermal aging embrittlement effects in cast stainless steels. While this electrochemical method can be easily employed to quantify thermal aging effects in materials aged at higher temperatures (e.g. greater than 350∘C), this study highlights the difficulties encountered when electrochemically evaluating the aging of materials exposed to nuclear power plant operating conditions.

In this work a new energy deposition treatment for the Serpent 2 Monte Carlo transport code is introduced. The treatment is implemented as a set of energy deposition modes, each of which offers a different combination of accuracy and required computational time. The most accurate mode uses the coupled neutron-photon transport available in Serpent 2. In addition to the new modes, a few other improvements such as a new energy deposition detector response was developed. The energy deposition treatment is demonstrated with simple LWR and LFR assembly level test cases. In the LWR cases the results are compared with MCNP6 on a high-level and a good agreement is achieved. In the LFR case differences in the energy deposition estimates of the different modes are highlighted. Based on the test cases, problems in the energy deposition data with ENDF/B-VII.1 and ENDF/B-VIII.0 are presented. Finally, future work concerning energy deposition capabilities of Serpent 2 are briefly discussed.

The use of modified couple stress theory to simulate the size-dependent phenomenon of composite laminate microplate is commonly limited to simple boundary conditions and mechanical bending load. The small-scale effects on bending and buckling on composite laminate microplate under complex boundary conditions in thermal environment have not been understood fully in the literature. Hence, this research develops, for the first time, a model to overcome the above limitation through the combination of a new modified couple stress theory and isogeometric analysis (IGA). By solving the governing equation using IGA, the thermal displacement, stress and thermal buckling load for various material length scale parameters are obtained. To satisfy the continuous shear stress condition at the layer interfaces, the equilibrium equations as integrated in-plane stress derivatives over the thickness are imposed. In addition, the non-uniform rational B-splines (NURBS) satisfy the higher-order derivative of shape function using the equilibrium equation. Furthermore, to show the effectiveness of presented model for capturing the size effect on thermal bending and thermal buckling of multi-ply laminate microplate, the influences of fiber orientation, thickness ratio, boundary condition and the variation in material length scale parameter are investigated.

The dynamic load in tubes due to detonation has a number of applications, such as in oil pipeline systems and pulse detonation engines. Various experimental, analytical, and numerical investigations have been conducted to study the mechanical, thermo-mechanical, and fracture behavior of tubes under internal detonation loads. Regarding numerical analysis, different approaches such as interface cohesive element, mesh-free, and extended finite element methods have been used to model the propagation of crack(s) in a tube. This paper presents a review of relevant literature pertaining to numerical and experimental analyses of detonation-driven deformation and fracture, and of studies based on the analytical investigation of moving loads in detonation tubes. The corresponding findings are discussed in detail, and possible avenues for future research are highlighted.

Biochar produced at an oxidative atmosphere shows distinct chemical properties compared to those of biochar produced at an inert atmosphere. However, there has been little investigation on the relationship between the oxidative atmosphere and the structure development of biochar, which can be useful information for the utilization of derived products. In this study, the effect of the oxygen atmosphere on the structure development of loblolly pine-derived biochar during thermal treatment was investigated. Quantitative analysis using solid-state direct polarization/magic angle spinning 13C nuclear magnetic resonance spectroscopy presented the existence of large fractions of aromatic and non-protonated carbons in the biochars treated at an oxidative atmosphere, implying highly condensed aromatic structures with large cluster sizes. Simultaneous thermogravimetic analyzer-differential scanning calorimetry was employed to demonstrate the difference in heat flow during the thermal treatment at two different atmospheres. Relatively large exothermic heat flow was observed when woody biomass was treated at 350 °C under an oxidative atmosphere which might be responsible for the difference in structural alteration. The series of observations suggested that compared to inert atmospheric conditions, admitting a limited amount of oxygen during thermal treatment of woody biomass could promote the evolution of condensed aromatic carbon structures.

Selected set of samples from JET ITER-Like Wall (JET-ILW) divertor tiles exposed in 2015-2016 has been analysed using Thermal Desorption Spectrometry (TDS). The deuterium (D) amounts obtained with TDS were compared with Nuclear Reaction Analysis (NRA). The highest amount of D was found on the top part of inner divertor which has regions with the thickest deposited layers as for divertor tiles removed in 2014. This area resides deep in the scrape-off layer and plasma configurations for the second (ILW-2, 2013-2014) and the third (ILW-3, 2015-2016) JET-ILW campaigns were similar. Agreement between TDS and NRA is good on the apron of Tile 1 and on the upper vertical region whereas on the lower vertical region of Tile 1 the NRA results are clearly smaller than the TDS results. Inner divertor Tile 3 has somewhat less D than Tiles 0 and 1, and the D amount decreases towards the lower part of the tile. The D retention at the divertor inner and outer corner regions is not symmetric as there is more D retention poloidally at the inner than at the outer divertor corner. In most cases the TDS spectra for the ILW-3 samples are different from the corresponding ILW-2 spectra because HD and D-2 release occurs at higher temperatures than from the ILW-2 samples indicating that the low energy traps have been emptied during the plasma operations and that D is either in the energetically deep traps or located deeper in the sample. For complete list of authors see http://dx.doi.org/10.1016/j.nme.2019.03.012

The efficiency of mixtures of ionic liquids (ILs) and molecular solvents in cellulose dissolution and derivatization depends on the structures of both components. We investigated the ILs 1-(1-butyl)-3-methylimidazolium acetate (C 4 MeImAc) and 1-(2-methoxyethyl)-3-methylimidazolium acetate (C 3 OMeImAc) and their solutions in dimethyl sulfoxide, DMSO, to assess the effect of presence of an ether linkage in the IL side-chain. Surprisingly, C 4 MeImAc-DMSO was more efficient than C 3 OMeImAc-DMSO for the dissolution and acylation of cellulose. We investigated both solvents using rheology, NMR spectroscopy, and solvatochromism. Mixtures of C 3 OMeImAc-DMSO are more viscous, less basic, and form weaker hydrogen bonds with cellobiose than C 4 MeImAc-DMSO. We attribute the lower efficiency of C 3 OMeImAc to “deactivation” of the ether oxygen and C2–H of the imidazolium ring due to intramolecular hydrogen bonding. Using the corresponding ILs with C2–CH 3 instead of C2–H, namely, 1-butyl-2,3-dimethylimidazolium acetate (C 4 Me 2 ImAc) and 1-(2-methoxyethyl)-2,3-dimethylimidazolium acetate (C 3 OMe 2 ImAc) increased the concentration of dissolved cellulose; without noticeable effect on biopolymer reactivity.

This work presents a numerical model to analyse the hygro-thermal behaviour of wooden bridge members. A multi-Fickian hygro-thermal model, previously implemented by some of the authors, is extended by including the dependency of wood sorption on temperature above and below zero degrees Celsius to predict moisture, temperature and relative humidity in wood under Northern European climates. The performance of the model in the presence of protective paints is particularly investigated. The finite element analysis based on the proposed model simulates the hygro-thermal behaviour of a glue-laminated beam of Älsvbacka Bridge located in Skellefteå (North of Sweden). The beam, coated by paints and claddings, was monitored by using wireless sensors in a previous research. Comparisons with the available measurements reveal that the numerical model is able to predict the moisture content in locations sheltered from rain and sun with moisture levels below the fibre saturation point. A study of the influence of different protective paints shows that the maximum and minimum moisture content at various depths along horizontal paths of the beam cross section, as well as the moisture gradients in different seasonal periods, are strongly affected by the type of paint. The proposed numerical approach is a promising tool to facilitate sensor-based monitoring techniques and to optimize the choice of protective paints for improved performance of timber bridges and other wooden structures under variable climates.

Hazardous zinc refinery residues that contain Ag and Hg are a typical complex material obtained from zinc oxygen pressure leaching and currently there are few economically viable methods for disposal or reuse. The research presented here offers an effective approach for the comprehensive recovery of Zn, Fe, Cu, Ag and Hg from this highly toxic waste. During the initial hot-acid leaching stage, leaching efficiencies of 96.3% Zn, 96.0% Fe and 97.5% Cu were obtained, whereas the leaching of Ag and Hg were

In this paper X2PCC (Calcium containing material X to Precipitated Calcium Carbonate) process wherein a steelmaking slag is used as a source of Ca for mineral carbonation of CO 2 was studied. Mineral carbonation refers to binding of CO 2 into mineral carbonates, here CaCO 3 . In the process, we first dissolve Ca selectively from the slag, then separate the solid phase and finally, bubble CO 2 into the solution to make precipitated calcium carbonate CaCO 3 . Based on our current understanding, the extraction step limits the process feasibility. In the experiments, ammonium chloride (NH 4 Cl) water solution was used as an extracting solvent with varying concentrations of 0, 0.5, 1 and 2 mol/L using slag to solvent ratio of 100 g/L. The main objective of this study was to determine the optimal concentrations of solvent and particle size for leaching out calcium from the slag. Tests were performed at room temperature with varying particle size and solvent concentration. The extraction behaviors of different size fractions of the slag, 0-50 μm, 50-74 μm and 74-125 μm were studied. Dissolution results showed that with high solvent concentrations calcium extraction efficiency increases but at the same time, other elements are leached, such as vanadium, silicon and magnesium that act as impurities in the subsequent carbonation stage. It was found that with the largest particles, Ca extraction becomes limited by mass transfer and the availability of Ca from the particle. Our hypothesis is that the surface layer of the particles gets blocked by reaction products and stops the reaction. With the smallest particle size, before the surface gets blocked, more calcium could be extracted and the maximum extraction efficiency was not reached.

This paper presents the development of the method for predicting the reusability of building components and whole structures and a pilot study of three different single-storey steel buildings in Finland. The method enables various building parts and products to be classified through a procedure to calculate their reusability index. These values can be further used to produce a single reusability indicator for the whole end-of-life scenario (e.g. complete or partial building reuse). The aggregated result of the whole building may be very useful when planning demolition or reconstruction works as well as when assessing the environmental impact of the new buildings. The main new thing explored in this paper is the possibility of integrating the economyaspect of the recovered components in the reusability assessment. Indeed, the reusability index developed earlier was purely based on the technical requirements of recovering, remanufacturing and reusing components. Hence, it was a technical reusability indicator. The possibility ofincluding information on the prospective marketability of the recovered component is a valuable extension to this method.

Ti-based metal-organic frameworks (NH2-MIL-125) were post synthetic modified through a facile strategy using bis-quinoline Mannich bases producing MIL-125-HQ. The modified material (MIL-125-HQ) was used as an absorbent for uptake of the heavy metals from wastewater. 1H NMR, FTIR, CHN and SEM-EDX analysis showed successful incorporation of hydroxyl quinoline moiety into the NH2-MIL-125 upon chemical reaction. The modified MIL-125-HQ showed high affinity for Pb(II) ions from water, and the amount of Pb(II) ions decrease sharply from 500 mg/L to 60 mg/L, within merely 30 min of exposure at pH7, 298 K and 2 g/L MIL-125-HQ. The maximum adsorption capacity of MIL-125-HQ for Pb(II), Cd(II), Cu(II) and Cr(III) was determined to be 262.1, 102.8, 66.9 and 53.9 mg/g, respectively.

International audience; Fab labs, which offer small-scale distributed digital fabrication, are forming a Green Fab Lab Network, which embraces concepts of an open source symbiotic economy and circular economy patterns. With the use of industrial 3D printers capable of fused particle fabrication/ fused granular fabrication (FPF/FGF) printing directly from waste plastic streams, green fab labs could act as defacto recycling centers for converting waste plastics into valuable products for their communities. Clear financial drivers for this process have not been studied in the past. Thus, in this study the Gigabot X, an open source industrial 3D printer, which has been shown to be amenable to a wide array of recyclables for FPF/FGF 3D printing, is used to evaluate this economic potential. An economic life cycle analysis of the technology is completed comprised of three cases studies using FPF for large sporting equipment products. Sensitivities are run on the electricity costs for operation, materials costs from various feed stocks and the capacity factors of the 3D printers. The results showed that FPF/FGF 3D printing is capable of energy efficient production of a wide range of large high-value sporting goods products. In all cases, a substantial economic savings was observed when comparing the materials and energy related costs to commercial goods (even for customized goods). Using locally-sourced shredded plastic represented not only the best environmental option, but also the most economic. For the case study products analyzed even the lowest capacity factor (starting only one print per week) represented a profit when comparing to high-end value products. For some products the profit potential and return on investment was substantial (e.g. over 1000%) for high capacity use of a Gigabot X. The results clearly show that open source industrial FPF/FGF 3D printers have significant economic potential when used as a distributed recycling/manufacturing system using recyclable feed stocks in the green fab lab context.

[Image: see text] This study relates to the release of non-cellulosic components (cell wall heteropolysaccharides, lignin, and extractives) from swollen wood fibers in the presence of an anionic surfactant (sodium dodecyl sulfate, SDS) at submicellar concentrations. Highly surface-active aggregates form between SDS and the leached, non-cellulosic components, which otherwise do not occur in the presence of cationic or nonionic surfactants. The in situ and efficient generation of liquid foams in the presence of the leached species is demonstrated. The foaming capacity and foam stability, as well as the foam’s structure, are determined as a function of the composition of the aqueous suspension. The results indicate that naturally occurring components bound to wood fibers are extractable solely with aqueous solutions of the anionic surfactant. Moreover, they can form surface-active aggregates that have a high foaming capacity. The results further our understanding of residual cell wall components and their role in the generation of foams.

Anatase TiO2 displaying dual morphologies were synthesized with a simple chemical route via a single step. A strong correlation between the dye sensitized solar cell (DSSC) device performance and the obtained dual morphologies are highlighted using relevant evidences from UV–vis and diffuse reflectance spectroscopy (DRS), Raman analysis, field emission scanning electron microscope, high resolution transmission electron microscope, current-voltage characteristics and impedance analysis. Structural investigation revealed that the interested medium in this work employed for the synthesis of TiO2 produced different types of dual morphologies such as nanospheres with nanoparticles (NSNP), microsphere decorated with nanoparticles (μSNP) and nanoparticles with stone like features (NPS). UV–vis and DRS results indicated the ability of the materials to assist with diffused reflectance and optical absorption of the screen printed photoanodes. In addition, an investigation of Raman vibrational characteristics was carried out in detail using synchronous and asynchronous 2D correlation analysis. The high intense Eg anatase mode of Raman spectrum was simulated using a phonon confinement model and its normalized spectra are compared with an experimental data. The resultant performances in the DSSCs were not indicative by the material properties; so, the charge transfer resistance (Rct) and recombination properties of the photoanode were investigated. These results showed that the Nyquist plot of NSNP possesses the smallest diameter, which reveals that the device based on NSNP offers the lowest Rct value that accounts for the higher conversion efficiencies when compared with the DSSC device based on photoanodes μSNP and NSP. It can be concluded that the improved power conversion efficiency shown by photoanode fabricated using NSNP has the dual role of optimum surface area for dye loading and light scattering centres. These properties, when optimized along with the offered pathway for electrolyte diffusion to the dye degenerationwith less Rct, could lead to better photoelectric conversion efficiency.

As a method of producing RFID tags, printed graphene provides a low-cost and eco-friendly alternative to the etching of aluminum or copper. The high resistivity of graphene, however, sets a challenge for the antenna design. In practice, it has led to using very large antennas in the UHF RFID far field tags demonstrated before. Using inductive near field as the coupling method between the reader and the tag is an alternative to the radiating far field also at UHF. The read range of such a near field tag is very short, but, on the other hand, the tag is extremely simple and small. In this paper, near field UHF RFID transponders with screen-printed graphene antennas are presented and the effect of the dimensions of the tag and the attachment method of the microchip studied. The attachment of the microchip is an important step of the fabrication process of a tag that has its impact on the final cost of a tag. Of the tags demonstrated, even the smallest one with the outer dimensions of 21 mm * 18 mm and the chip attached with isotropic conductive adhesive (ICA) was readable from a distance of 10 mm with an RF power marginal of 19 dB, which demonstrates that an operational and small graphene-based UHF RFID tag can be fabricated with low-cost industrial processes., Comment: 8 pages, 9 figures. IEEE Transactions on Components, Packaging and Manufacturing Technology, 2019

l -proline was used to prepare chiral, tridentate amino acid phenol proligands H2L1–4. These proligands react with vanadium precursors VO(acac)2, VOSO4∙5H2O and VO(OPr)3 in methanol to form the corresponding oxidoalkoxidovanadium( v ) complexes 1–4. The complexes crystallize from methanol, and are octahedrally coordinated with a general formula [VO(L1–4)(OMe)(MeOH)]. In solution, however, they adopt several different conformations or isomeric structures depending on the solvent.

Owing to their superior mechanical strength and structure similarity to the extracellular matrix, nanocelluloses as a class of emerging biomaterials have attracted great attention in three-dimensional (3D) bioprinting to fabricate various tissue mimics. Yet, when printing complex geometries, the desired ink performance in terms of shape fidelity and object resolution demands a wide catalogue of tunability on the material property. This paper describes surface engineered biomimetic inks based on cellulose nanofibrils (CNFs) and cross-linkable hemicellulose derivatives for UV-aided extrusion printing, being inspired by the biomimetic aspect of intrinsic affinity of heteropolysaccharides to cellulose in providing the ultrastrong but flexible plant cell wall structure. A facile aqueous-based approach was established for the synthesis of a series of UV cross-linkable galactoglucomannan methacrylates (GGMMAs) with tunable substitution degrees. The rapid gelation window of the formulated inks facilitates the utilization of these wood-based biopolymers as the feeding ink for extrusion-based 3D printing. Most importantly, a wide and tunable spectrum ranging from 2.5 to 22.5 kPa of different hydrogels with different mechanical properties could be achieved by varying the substitution degree in GGMMA and the compositional ratio between GGMMA and CNFs. Used as the seeding matrices in the cultures of human dermal fibroblasts and pancreatic tumor cells, the scaffolds printed with the CNF/GGMMA inks showed great cytocompatibility as well as supported the matrix adhesion and proliferative behaviors of the studied cell lines. As a new family of 3D printing feedstock materials, the CNF/GGMMA ink will broaden the map of bioinks, which potentially meets the requirements for a variety of in vitro cell-matrix and cell-cell interaction studies in the context of tissue engineering, cancer cell research, and high-throughput drug screening.

Background The large-scale clinical problem caused by unacceptable tribological behaviour of certain large diameter metal-on-metal prosthetic hips has directed attention to adverse condition testing. High metal-on-metal wear is connected with adverse reaction to metal debris. Friction is important because high friction may be associated with high wear, risk the fixation of the cup, and cause detrimental heating of periprosthetic tissues. Methods A friction measurement system was added to a multidirectional, established hip joint wear simulator, and its functionality was evaluated. In preliminary tests, a 50 mm diameter metal-on-metal prosthesis was tested in an optimal acetabular cup inclination angle (48°) and in a steep angle (70°) using a normal peak load (2 kN) and an increased peak load (3 kN). The test length was 100 h. Long-term adverse condition tests of 3 million cycles were run for three 52 mm metal-on-metal prostheses. The lubricant was diluted calf serum at 37 °C. Findings In the 100 h tests, metal-on-metal frictional torque was not highly sensitive to the angle, load and serum degradation, and it was close to that of a conventional 28 mm prosthesis with a polyethylene cup, mostly below 5 Nm. However, a manyfold higher frictional torque (10 to 20 Nm) was observed in long-term metal-on-metal tests with substantial wear. Interpretation To obtain a realistic prediction of the frictional behaviour of a hip design, long-term, multidirectional wear tests are necessary. The friction should preferably be measured during the wear test. In addition to normal conditions, adverse condition testing is strongly recommended.

This paper presents studies on the utilization of aluminosilicate-based mining tailings as raw materials for mullite-based ceramics. Based on the 3:2 stoichiometric composition, mullite was synthesised by reactive sintering with a series of powder mixtures with alumina additions. X-ray diffractometry and scanning electron microscopy analyses revealed that, at the specific mineralogical composition, mullite structure formed surrounded by an amorphous glass phase in reaction-sintered powder mixtures. Results demonstrated that the chemical and mineralogical composition of mining tailings do have an effect on mullite formation possibilities and, only with the particular mineralogical composition, the mullite formation is possible regardless of the correct Al:Si ratio in tailings. Physical and mechanical properties of the formed ceramics were defined, showing comparable values to 3:2 mullite reference. Mullite structure formation enables a better thermal resistance up to above 1450 °C of the formed tailings-based ceramics compared to other aluminosilicates, reflecting their utilization potential for refractory ceramic applications. acceptedVersion

Dust constitutes one of the major environmental concerns near many aggregate quarries, with crushing often being the most significant source. In this study, dust emissions and dispersion measurements were conducted under real operating conditions at six aggregate quarries in southern Finland. Five of them represent granitic rocks and one a limestone quarry. Dust concentrations during crushing were measured at varying distances with time intervals of five seconds. The variation in dust concentration was high within all the measured distances, ranging from 10 to 200 m. Crushing produces mainly coarse (TSP and PM10) dust particles, which settle near the dust source. The mass concentration of coarse particles in this investigation varied from few tens of μg/m3 to over 6.5 × 103 μg/m3 downwind from the crusher. The mass concentration of fine particles (PM2.5 and PM1) ranged between ten μg/m3 and few hundreds of μg/m3 downwind from the crusher. The fine particles originated mainly from machinery used in the quarries and remote sources, such as nearby traffic. In quarries operating with secondary crushing, the background concentrations were achieved approximately from a 350 m distance for coarse particles. Local dust sources, such as hauling, impacted the results inside the quarry. Crushing produced more dust compared to comparable studies for drilling. The dust concentrations at the limestone quarry were approximately 50% of concentrations measured at quarries with granitic rocks.

The present work offers a study on the engineering implications of the recovery of valuable fractions from industrially collected lithium battery (LIB) waste by mechanical and hydrometallurgical processes in HCl media. Direct leaching of LIB waste provides a possibility for Li extraction, a component that is lost into the slag fraction in the state-of-art high temperature processes. The challenges arising from the heterogeneous composition of industrial battery waste are highlighted, and the behavior of main metals present such as Co, Cu, Li, Mn, Ni and Al is observed. It is shown that mechanical separation processes can form fractions rich on Cu and Al, although subsequent refining stages are necessary. Regarding direct leaching, fast kinetics were found, as complete Li dissolution can be achieved in ca. 120 min. Furthermore, high solid/liquid ratio (>1/10) is required to increase metal value concentrations, resulting in a viscous slurry due to the graphite, plastics and other undissolved materials, which challenges filtration and washing of leach residue. Neutralization of the product liquid solution (PLS) result in co-precipitation of valuable battery metals along with Fe and Al. The highest value of LIBs lies in Co, subjected for solvent extraction (SX) or direct precipitation to make an intermediate product. SX can provide selectivity whereas Na2CO3 precipitation provides a fast route for Co-Ni bulk production. Li2CO3 precipitation from the remaining PLS is possible as zabuyelite - however, due to heterogeneity of the battery waste, the recovery of Li2CO3 with battery-grade purity remains a difficult task to be achieved by direct precipitation route.

The interest in totally bio-based materials is increasing due to their low carbon footprint and improved properties through intensive research. Polylactide (PLA)-based cellulose fibre compounds are finding their way into various injection-moulded applications. In addition to gain high-performance PLA–cellulose pulp fibre composites, there are also needed for additives such as plasticizers and coupling agents in the compounds. This research presents the use of a renewable material–based combined plasticizer-coupling agent as an additive in PLA bleached softwood kraft pulp (BSKP) composite. An epoxy-modified linseed oil showed capability for cross-linking PLA and cellulose fibre so enabling simultaneously improved strength tensile and impact properties for composite materials when added in amount of below 8% to fibre.

Growing metal–organic frameworks (MOFs) around biomolecules has recently emerged as a promising method to combine natural and synthetic materials. In parallel, cellulose nanocrystals (CNCs) have fo...

Solute trapping is an important phenomenon in rapid solidification of alloys, for which the continuous growth model (CGM) of Aziz et al. [1] is a popular sharp interface theory. By modulating the so-called anti-trapping current and using asymptotic analysis, we show how to quantitatively map the thin interface behavior of an ideal dilute binary alloy phase field model onto the CGM kinetics. We present the parametrizations that allow our phase field model to map onto the sharp interface kinetics of the CGM, both in terms of partition coefficient k ( V ) and kinetic undercooling. We also show that the mapping is convergent for different interface widths, both in transient and steady state simulations. Finally we present the effect that solute trapping can have on cellular growth in directional solidification. The presented treatment for solute trapping can be easily implemented in different phase field models, and is expected to be an important feature in future studies of quantitative phase field modeling in quasi-rapid solidification regimes, such as those relevant to metal additive manufacturing.

The bagasse of Agave tequilana Weber is one of the most abundant agroindustrial wastes in the state of Jalisco. However, at the present time, there is no technical use for this waste, and its high availability makes it an environmental problem. 1e objective of this research was to take advantage of this waste and give it an added value to be used in the elaboration of advanced materials. In this sense, the agave bagasse cellulose was obtained using an organosolv method. To obtain the nanofibrils, the cellulose was passed through 6 cycles of a microfluidizer. 1e material was classified by FTIR, confirming the presence of the functional groups (O-H, C-H, C-C, and C-OC), characteristics of cellulose, and the elimination of hemicellulose and lignin present in agave bagasse without treatment. 1e X-ray diffraction technique allowed the determination of the degree of crystallinity of the cellulose nanofibers, which was 68.5%, with a negative zeta potential of −42 mV. 1e images from the atomic force microscopy helped for the observation of the degree of fibrillation in the cellulose, and with the software ImageJ, the average diameter of the nanofibers was determined to be 75 ± 5 nm with a relatively uniform length of 1.0–1.2 μm. Finally, by means of thermogravimetric analysis, it was found that the obtained cellulose nanofibers (CNFs) supported high temperatures of thermal decomposition, so it was concluded that due to the diameter of the fibrils, the high resistance to pressure, and elasticity, the nanofibrils obtained in this investigation can be used in the elaboration of advanced materials. El bagazo de Agave tequilana Weber es uno de los residuos agroindustriales más abundantes en el estado de Jalisco. Sin embargo, en la actualidad, no existe un aprovechamiento técnico de estos residuos, y su alta disponibilidad los convierte en un problema ambiental. El objetivo de esta investigación fue aprovechar este desecho y darle un valor agregado para ser utilizado en la elaboración de materiales avanzados. En este sentido, la celulosa del bagazo de agave se obtuvo mediante un método organosolv. Para obtener las nanofibrillas, la celulosa se pasó por 6 ciclos de un microfluidizador. El material 1e fue clasificado por FTIR, confirmando la presencia de los grupos funcionales (O-H, C-H, C-C y C-OC), características de la celulosa, y la eliminación de hemicelulosa y lignina presentes en el bagazo de agave sin tratamiento. La técnica de difracción de rayos X 1e permitió determinar el grado de cristalinidad de las nanofibras de celulosa, que fue del 68,5%, con un potencial zeta negativo de −42 mV. Las imágenes 1e del microscopio de fuerza atómica ayudaron a observar el grado de fibrilación en la celulosa y, con el software ImageJ, se determinó que el diámetro promedio de las nanofibras era de 75 ± 5 nm con una longitud relativamente uniforme de 1,0 a 1,2 μm. . Finalmente, mediante análisis termogravimétrico se encontró que las nanofibras de celulosa (CNFs) obtenidas soportaban altas temperaturas de descomposición térmica, por lo que se concluyó que debido al diámetro de las fibrillas, la alta resistencia a la presión y la elasticidad, las nanofibrillas obtenidos en esta investigación pueden ser utilizados en la elaboración de materiales avanzados. Universidad Nacional, Costa Rica Aalto University, Finlandia University of Guadalajara, México Escuela de Química

A research on the effect of different buffers on the pH range of 6–10 on the thin oxide-covered surface of aluminum cathode has been conducted under the conditions corresponding with those generally used in bioaffinity assays or other determinations made by using aluminum probe based on time-resolved cathodic electrochemiluminoimmuno assay (tr-ECLIA or tr-CECLIA) detection. The experiments have been conducted on impedance and cathodic electrochemiluminescence (CECL) basis using a strong long lifetime having electroluminophore Tb(III)-1 chelate where the ligand 1 is 2,6-bis[N,N-bis(carboxymethyl)aminomethyl]-4-benzoylphenol and Ruthenium(II) tris(2,2′–bipyridine) (Ru(bpy)32+) as the CECL model luminophores. The results point out that the natural oxide layer at the electrode surface does not essentially change as to its thickness but as to its resistance, it can be concluded that the best buffer in these luminophore determinations based on CECL and Al probe use is borate buffer adjusted to pH around 7–8 where the surface of aluminum has its neutral character. In the bioaffinity assays the meaning of the buffer seems to be more difficult to realize due to the complex character of the surface with plenty of different coatings and special handling steps but still with the aforementioned borate buffer the results were noticed to be the most stabile. The tests also pointed out that the character of the pure aluminum surface and the oxide layer above it without any other coatings could be strongly affected by the surrounding solution composition and in that way to the durability of the aluminum probe already during the quite short exposure times. The reported results are useful especially in the field of CECL based on aluminum probe use but could also in a certain extent to be utilized in a large scale of analysis considering the use of aluminum probes.

The reaction of various platinum metals (M = Ru, Os, Rh, Ir, Pd, Pt) with KBrF4 was investigated upon heating their mixtures to 400 °C. The formation of potassium fluorido platinum metallates in oxidation states +4 or +5, K2MF6 or KMF6, respectively, was observed in all cases. The obtained products were tested for their stability in water. Depending on the platinum metal, they were either stable, were reduced to the oxidation state +4, or were hydrolyzed to so far unidentified phases. K2RuF6, K2OsF6, α-K2PdF6, β-K2PdF6, which were previously only poorly characterized, were structurally reinvestigated by single crystal or powder X-ray diffraction, Raman and IR spectroscopy. The three former compounds crystallize isotypic in the trigonal, the latter in the hexagonal crystal system. The α→β phase transition of K2PdF6 was found to be reconstructive. Quantum chemical calculations were used to investigate the crystal structures.

Synthetic structural materials of high mechanical performance are typically either of large weight (for example, steels, and alloys) or involve complex manufacturing processes and thus have high cost or cause adverse environmental impact (for example, polymer-based and biomimetic composites). In this perspective, low-cost, abundant and nature-based materials, such as wood, represent particular interest provided they fulfill the requirements for advanced engineering structures and applications, especially when manufactured totally additive-free. Here, we report on a novel all-wood material concept based on delignification, partial surface dissolution using ionic liquid (IL) followed by densification resulting in a high-performance material. A delignification process using sodium chlorite in acetate buffer solution was applied to controllably delignify the entire bulk wooden material while retaining the highly beneficial structural directionality of wood. In a subsequent step, obtained delignified porous wood template was infiltrated with an IL 1-ethyl-3-methylimidazolium acetate, [EMIM]OAc and heat activated at 95 degrees C to partially dissolve the fiber surface. Afterward, treated wood was washed with water to remove IL and hot-pressed to gain a very compact cellulosic material with fused fibers while retaining unidirectional fiber orientation. The obtained cellulose materials were structurally, chemically, and mechanically characterized revealing superior tensile properties compared to native wood. Furthermore, suggested approach allows almost 8-fold tensile strength improvement in the direction perpendicular to fiber orientation, which is otherwise very challenging to achieve.

The goal of this study was to assess the environmental impact of cellulose carbamate fiber production, using discarded cotton textiles as raw material, and compare the results to reference cotton and viscose fibers. Life cycle inventory and assessment was conducted for two production process scenarios within a cradle-to-gate system. Carbon footprint, water use, and water scarcity footprint were assessed. The results show that the carbon footprint of a cellulose carbamate factory integrated with a pulp mill, and that recycles water and chemicals in energy-intensive operations, is comparable to viscose production in Europe. Cellulose carbamate fiber production consumes less than 2% and 25% of the water consumed by cotton and viscose fiber production, respectively. For a factory located in Äänekoski in Finland, the water scarcity footprint was 15 m 3 water eq. per 1000 kg carbamate fiber. For Augsburg, Germany, a likely alternative location, the water scarcity footprint was 18 m 3 water eq. per 1000 kg carbamate fiber. Carbon footprint and local impact of water use give information that can be utilized to determine optimal locations for a carbamate factory. The study also indicated that discarded cotton textiles can be used as a cellulosic feedstock without increasing the carbon footprint and water use compared to the commercial viscose process. Additionally, by using cellulose carbamate technology, occupational health risks and the environmental burden of carbon disulfide and hydrogen sulfide emissions from viscose process vents can be avoided.

Tailings from an industrial copper slag cleaning milling and flotation circuit have been pre-reduced at low temperatures, well below its melting point, using CH4-H2-Ar mixtures with the aim of metallizing its iron oxide component to metallic iron. The treatment carried out at 700–900 °C, with a duration of up to 90 min, indicated a complete transformation of magnetite within the first 30 min of the process. At the same time, significant fractions of its harmful impurities, antimony, arsenic, bismuth, lead and zinc, present as oxides in the slag were reduced from magnetite and the glassy inter-granular phase, and removed from the slag as flue dust in the process off-gas. The obtained fine slag powder with low impurity contents can be melted after the pre-reduction to synthetic rock or to fast cooled slag granules for further use.

Silver nanoparticles (NPs) are known to provide antimicrobial properties for surfaces. However, there are environmental concerns due to reports of toxicity after exposure to the environment during or after end-use. Immobilizing silver NPs to the surface of substrates could ensure that particles are readily available for antibacterial activity with limited environmental exposure. A plasma coating on top of silver NPs could improve the adhesion of NPs to a substrate, but it could also impede the release of silver NPs completely. Furthermore, silver has been shown to require direct contact to demonstrate antibacterial activity. This study demonstrates immobilization of silver NPs with plasma coating onto a surface while maintaining its antibacterial properties. Silver NPs are simultaneously synthesized and deposited onto a surface with liquid flame spray aerosol technique followed by hexamethyldisiloxane plasma coating to immobilize the NPs. Atomic force microscope scratch testing is used to demonstrate improved nanoparticle adhesion. Antibacterial activity against gram-negative Escherichia coli is maintained even for plasma coating thicknesses of 195 nm. NP adhesion to the surface is significantly improved. Gram-positive Staphylococcus aureus was found be resistant to all the plasma-coated samples. The results show promise of using plasma coating technology for limiting NP exposure to environment.

This paper presents a novel difference imaging approach based on the recently developed parametric level set (PLS) method for estimating the change in a target conductivity from electrical impedance tomography measurements. As in conventional difference imaging, the reconstruction of conductivity change is based on data sets measured from the surface of a body before and after the change. The key feature of the proposed approach is that the conductivity change to be reconstructed is assumed to be piecewise constant, while the geometry of the anomaly is represented by a shape-based PLS function employing Gaussian radial basis functions (GRBFs). The representation of the PLS function by using GRBF provides flexibility in describing a large class of shapes with fewer unknowns. This feature is advantageous, as it may significantly reduce the overall number of unknowns, improve the condition number of the inverse problem, and enhance the computational efficiency of the technique. To evaluate the proposed PLS-based difference imaging approach, results obtained via simulation, phantom study, and in vivo pig data are studied. We find that the proposed approach tolerates more modeling errors and leads to a significant improvement in image quality compared with the conventional linear approach.

Photodeposition has been demonstrated to be a reliable tool for the growth of co-catalyst nanoparticles on titanium dioxide. The current state of investigation on the technique, however, lacks a comprehensive study on the collective influence of different process parameters, preferring to confront the effect of a single parameter at a time. This paper presents a parametric study on photodeposition of platinum nanoparticles from liquid precursors on ALD-grown titanium dioxide, applicable to the fabrication of photocatalytic composite materials. In the described process, a systematic and rigorous statistical analysis of the photodeposition parameters is conducted, assessing the influential parameters that control and predict the size, density and loading of the deposited nanoparticles. The results are assessed by scanning electron microscopy, statistical analysis of micrographs, and X-ray photoelectron spectroscopy. This confirms the simplicity and the viability of photodeposition as a method for the self-assembly of metal nanoparticles from liquid precursors and provides all-round insight on the role of parameters such as the concentration of sacrificial reagents, the presence of H 2SO 4, and the concentration of the precursor solution, in the chemical and structural properties of the deposited nanoparticles.

A large-scale investigation into the effect of increased aeration on heap leaching of a pyrrhotite-rich pentlandite ore was commenced at the Terrafame mine in Finland. The typical reference air feed amount in operation is approximately 0.05 m3/metric ton/h, fed from one direction of the 330 to 350 m wide heap. In the current study approximately 62% higher air feed vs. reference operation was trialed by installing another layer of aeration from the opposite direction of the heap. The hypothesis was that air distribution across the ore would be improved and that the increase in air feed would result in faster oxidation of pyrrhotite, leading ultimately to improved recovery of valuable metals. The heaps were observed for 150 days after stacking. The results revealed an increase in the leaching rates of several metals: manganese, magnesium, iron, nickel and zinc leached 14, 171, 142, 1932, and 1309% more in the presence of extra aeration during the observation period. In addition, applying the extra air showed a 324% increase in the generation of acid within the heap.

Allocating environmental impacts within life cycle assessment (LCA) is a recognised methodological problem. Different allocation methods have been developed to fulfil the various goals of LCA studies. At present, there is neither a consensus regarding the method to be used nor a one-fits-all method for dealing with recycling in LCA. The paper discusses some of the main allocation procedures practised in the pulp and paper industry, namely those covered by ISO/TS 14067:2018, GHG Protocol/PAS 2050, and the Product Environmental Footprint (PEF). All in all, the allocation method described in the ISO/TS 14067:2018 standard was considered the most appropriate to account for open-loop recycling of paper products. However, the method neither considers the number of subsequent uses of recycled fibres, nor the recycled fibre age. Yet, both of them are considered especially important in the open-loop recycling of paper products. In order to account for these aspects, the present study proposes an advanced, step-wise approach to handle allocation in LCAs accounting for the open-loop recycling of paper products. The advanced approach is based on the fibre mass flow model used to calculate the mean fibre age and the mean number of uses of paper products within the European context. The approach was validated with the data from the pulp and paper industry, particularly examining the newsprint paper grade with different contents of recycled fibre and fibre age. The paper, however, introduces all the parameters required to perform allocation based on the proposed method for other paper grades. The categpory of global warming potential was considered in the study as an illustrative example. yet the method could be applied to other impact assessment categories. The results calculated using the proposed allocation approach were compared to those obtained with the allocation methods described in the GHG Protocol/PAS 2050 and the PEF. The proposed allocation method can be used to guide further development of available standards and the product category rules, which will contribute to increased harmonisation and consistency of LCA studies in the pulp and paper sector, as well as to the enhanced practical implementation of LCA in industry.

We conducted the first comparative exploration on lignin containing cellulose nanofibril films prepared alternatively from willow bark and wood using a highly recyclable acid hydrotrope, aqueous p-toluenesulfonic acid, as a sustainable means for isolating the nanofibrils. The nanofibrils of willow bark were hydrophobic and produced dense films of high strength under hot pressing. The hydrophobicity resulted from condensation of the residual lignin with low molecular weight aromatic substances of the bark and hydroxymethylfurfural formed in situ from fructose that is also present in the bark.

Effect of point defects such as vacancies and interstitials on the work function of β-Ga2O3 thin films grown by pulsed laser deposition was investigated. Relative change in Ag3 and Ag6 Raman phonon modes indicated formation of oxygen and gallium vacancy defects. The surface potential mapping of Ga2O3 thin films was performed by Kelvin probe force microscopy. Analytical calculations showed variation in work function with oxygen pressure. The work function values at extreme growth pressure conditions were found to be very high. Hence, Fermi level was pinned at the mid-gap energy in both oxygen-deficient condition and oxygen-rich conditions which is attributed to oxygen and gallium vacancy defects. This mechanism of controlling Fermi level pinning in β-Ga2O3 paves the way to fabricate high performance electronic devices.