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In this paper, we aim to reconstruct the unknown Robin coefficient and unknown heat flux simultaneously in an elliptic system from Cauchy data on arbitrarily small portion of accessible boundary. A novel logarithmic type stability in terms of the negative Sobolev norms is established. [ABSTRACT FROM AUTHOR]

• Compressed air-driven large cross-section (3m×3 m) shock tube is developed. • Blast test on seven unreinforced and SPUA-retrofitted brick MIWs is conducted. • Applicability of theoretical calculation and numerical simulation methods is verified. • Improved evaluation criteria of unreinforced and SPUA-retrofitted MIWs are given. • W - R diagrams for the blast-resistant assessment of typical MIWs are proposed. Unreinforced masonry infill walls (MIWs) are prone to crack, fragment, and even collapse under blast loads, threatening the safety of building structures, as well as the inside occupants and equipment. Spray polyurea (SPUA) has been proven to be an excellent retrofitted material for MIWs to improve their blast resistance. Aiming to study the dynamic behaviors of brick MIWs under far-field range blast loads, the successive blast tests on seven unreinforced and SPUA-retrofitted brick MIWs with different thicknesses and boundary constraints were first carried out based on the developed compressed air-driven large cross-section (3m×3 m) shock tube. It was indicated that the blast resistance of MIWs significantly improved by increasing wall thickness and strengthening boundary constraint; SPUA coating can improve the blast resistance of MIWs and effectively suppress the debris generation and splash. Then, the equivalent single degree of freedom model based theoretical calculation and the simplified micro-model based numerical simulation methods previously established by authors were briefly introduced. Additionally, the dynamic behaviors of seven examined MIWs were further predicted and compared with test results, which verified the applicability of theoretical calculation and numerical simulation methods. Finally, the improved damage and failure evaluation criteria of unreinforced and SPUA-retrofitted MIWs were given, and the charge weight and standoff distance diagrams of typical MIWs were proposed based on the validated theoretical and numerical methods as well as the improved criteria, which would provide a helpful reference for blast-resistant evaluation and retrofitted design of brick MIWs. [ABSTRACT FROM AUTHOR]

In this study, we have described a novel reaction between 1,4-enynyl-3-ols and alkyl bromides. The reaction was carried out in the presence of Ag 2 O, following a free radical 1,2-alkynyl migration pathway, which was confirmed through control experiments. This methodology offers several advantages, including high efficiency and a wide range of applicable substrates. A novel alkynylation/alkylation reaction between 1,4-enynyl-3-ols and alkyl bromides was herein described. The Ag 2 O-mediated transformation proceeded in a free radical 1,2-alkynyl migration pathway, which was verified by the control reactions. The methodology enjoyed priorities such as high efficiency and broad substrate scope. [Display omitted] • Alkynylation/alkylation reaction between 1,4-enynyl-3-ols and alkyl bromides. • A Ag 2 O-catalytic reaction. • A free radical 1,2-alkynyl migration reaction. [ABSTRACT FROM AUTHOR]

Abstract The dynamic response and design optimization of clamped sandwich panels comprising two aluminum alloy face-sheets and a layered-gradient closed-cell aluminum foam core subjected to air-blast loading were examined in this study. The numerical approach was first validated by blast test results of sandwich panels with monolithic aluminum foam cores, and then the dynamic responses of layered-gradient core sandwich panels were briefly discussed in terms of deflection response and energy absorption. Two surrogate model methods (i.e., response surface method – RSM, and radial basis function – RBF) were adopted to construct objective response functions, and the single-objective adaptive response surface method (ARSM) and multi-objective genetic algorithm (MOGA) were used for the defined optimization problem. The optimization results show the trade-off relationships among the maximum energy absorption, minimum structural mass and minimum deflection, and the advantage of "Pareto front" in such design circumstances. Furthermore, the applicability and accuracy of RSM and RBF agent models in the multi-objective design optimization (MDO) of sandwich panels with layered-gradient foam cores under air-blast loading were also compared and revealed. [ABSTRACT FROM AUTHOR]

Bioproducts are chemicals derived from renewable biological resources and have the potential to replace petrochemicals in the future to tackle the arising environmental problems. Among them, lactic acid (LaA) is attracting significant focus from both academia and industry due to its wide application in our daily life. In this study, lactic acid is produced from the chemo-catalytic converting the glucose over the homogeneous ErCl 3 catalyst in an aqueous solution. The highest LaA yield of 97% was obtained at a full glucose conversion on this homogeneous catalyst at 260 °C through process optimization. Furthermore, the techno-economic analysis (TEA) was leveraged for the concept design of LaA biorefineries. Three parameters, namely the selling price of LaA, the price of glucose, and the catalyst recyclability were identified for the overall profit. Therefore, this work highlights the notable ability of TEA for the concept design or simulation to screen the promising biorefinery industrial process, and intuitively provide us with the internal rate of return of a certain chemical process. Thus, this work is supposed to provide the feasibility of LaA acid production from a chemo-catalytic process from both the technical and scientific points of view. [Display omitted] • A high lactic acid yield was obtained on the ErCl 3 homogeneous catalyst. • The potential of using converting glucose to lactic acid was analyzed. • Concept design and tech-economic analysis were performed. [ABSTRACT FROM AUTHOR]

Catalytic converting the lignin-derived bio-oil to liquid fuel is one promising methodology to reduce the dependence on petroleum-based fuel while easing the atmospheric carbon dioxide burden. Hydrodeoxygenation (HDO) is one commonly used method to convert and upgrade bio-oil from biomass. In the present work, a Ru-promoted MoFeP/Al 2 O 3 catalyst was prepared and evaluated the HDO performance by converting two model compounds, guaiacol and anisole with a batch reactor at 250 °C. This catalyst shows a quite good HDO performance over the two model compounds, in which, oxygen was removed from the phenolic and hydrocarbons were produced as the product. Kinetic studies were also performed to build the reaction network and elucidate the reaction pathway of guaiacol and anisole HDO reactions. The primary, secondary, and tertiary products can be identified for the HDO reactions. A better understanding of HDO chemistry from the fundamental study can lead to more efficient catalysts for the target products. [Display omitted] • A highly active Ru-MoFeP/Al 2 O 3 was proposed in HDO reaction. • Reaction network of guaiacol and anisole HDO reaction were proposed. • Primary product, secondary or tertiary products can be identified. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC) has been widely applied in aerospace and railway industries, and it is imperative to improve its fire safety related properties, especially heat release properties. Particularly, the MARHE value (maximum average rate of heat emission) directly obtained from the cone calorimeter (CONE) test is a comprehensive property that is presented in the EN45545-2 standard developed by the EU. In order to study the effect of flame retardants on the MARHE of polycarbonate, four flame retardants with different flame retardant mechanisms were used to prepare low heat release PC. CONE was used to characterize the heat release performance of PC, focusing on exploring the factors affecting MARHE and the method of preparing low heat release materials. The flame-retardant mechanism of PC was studied by SEM and TG/DTG. Meanwhile, the flame retardant index (FRI) is calculated as a reference for the flame retardant performance of PC. Results show the MARHE of HPCTP/PC is reduced by 31.12%, and it is confirmed that MARHE is influenced by time to ignition (TTI), peak heat release rate (PHRR), total heat release rate (THR), and the shape of the peak. Mica-RDP/PC materials were prepared based on the conclusions of MARHE derivation. RDP and Mica play a typical synergistic flame-retardant mechanism, with MARHE reductions from 20.31% to 20.00% of the single-component systems to 31.39%. All FRI values of PC materials are in the range of Good flame retardancy. This study provides a feasible way for the deep understanding and wide application of MARHE and the improvement of the fire safety performance of PC. • Analyzing influencing behavior to MARHE, studying flame-retardant mechanism via CONE and carbon residue. • Mathematical derivation for MARHE to further guide experiment, MARHE drops by 31% via synergistic effect, and all FRI values are in good. • To meet the requirements of EN45545-2 for MARHE on low heat release PC material. [ABSTRACT FROM AUTHOR]

In this work, a simple, rapid and facile one-pot wet-chemical co-reduction method is developed for synthesis of bimetallic Au–Pt alloyed nanochains supported on reduced graphene oxide (Au–Pt NCs/RGO), in which caffeine is acted as a capping agent and a structure-directing agent, while no any seed, template, surfactant or polymer involved. The as-prepared nanocomposites display enlarged electrochemical active surface area, significantly enhanced catalytic activity and better stability for methanol and ethylene glycol oxidation, compared with commercial Pt–C (Pt 50 wt%), PtRu–C (Pt 30 wt% and Ru 15 wt%) and Pt black. [ABSTRACT FROM AUTHOR]

The metal-organic framework Ni-MOF-74 was synthesized and then characterized by XRD, SEM, and N 2 adsorption techniques. The unary isotherms of CO 2 , CH 4 , C 3 H 6 , and C 3 H 8 on Ni-MOF-74 were measured by means of a volumetric method. The Langmuir–Freundlich model appropriately describes the adsorption equilibrium data. The selective separations of two mixtures CO 2 /CH 4 and C 3 H 6 /C 3 H 8 on Ni-MOF-74 were experimentally investigated by a breakthrough-column technique. Simulations of transient breakthroughs for the two mixtures agree well with the experimental data. In addition, with the inclusion of intra-crystalline diffusion into the simulations, the quality of the simulated breakthrough curves are improved and agree better with the experimental data. The results indicate that Ni-MOF-74 might be a candidate for the removal of C 3 H 6 from C 3 H 6 /C 3 H 8 mixtures and for the efficient separation of CO 2 from CH 4 . [ABSTRACT FROM AUTHOR]

This paper aims to investigate the Rayleigh–Bénard convection of Al 2 O 3 /water nanofluids in a cavity considering the sedimentation, thermophoresis, and Brownian motion. For this purpose, a numerical simulation is carried out using finite volume method to obtain the flow patterns and heat transfer characteristics of nanofluid flow inside the cavity. The results are presented for volume fractions up to 4%, Rayleigh numbers between 10 4 and 8 × 10 4 where the temperature difference between top and bottom walls is between 2 and 10 °C. To validate the numerical solution, comparisons are made between the numerical results and experimental data available in the literature. The comparisons unfold that the results of numerical work are in a good agreement with the previous experimental results. [ABSTRACT FROM AUTHOR]

Highlights: [•] Biochar treatment at 20–40tha−1 reduced rice Cd by 20%–90% from metal polluted rice fields. [•] Grain Cd under biochar treatment fell in a safe level by 0.4mgkg−1 in soils with Cd in range 0.16–4.83mgkg−1. [•] Biochar amendment caused Cd immobilization primarily due to the liming effect by biochar. [Copyright &y& Elsevier]

Abstract: The influence of adsorbed sulfide (S2− ads) on CO monolayer electro-oxidation reaction (CMOR with M for monolayer to emphasize that oxidation always starts with a saturated CO coverage) on carbon-supported Pt nanoparticles (Pt/C NPs) was investigated using electrochemical and in situ ATR-SEIRAS (attenuated total reflection-surface enhanced IR absorption spectroscopy) techniques. An enhanced kinetics of CMOR on the S2− ads-Pt/C was observed by potentiodynamic CO stripping and potentiostatic CO oxidation analyses. Electrochemical impedance measurements revealed a weakened bonding of oxygen-containing species with the S2− ads-Pt/C surface as compared with the clean Pt/C surface, which we believe was the main reason for the observed enhanced CMOR by the S2− ads. The in situ SEIRAS data showed the existence of both linear- and bridge-bonded CO (COL and COB respectively) in all samples and that the sulfide adsorption increased substantially the fraction of the former on the available Pt sites and facilitated the conversion between them. Our results also indicate that the frequently observed pre-CMOR current arises most likely from oxidation of weakly-bonded CO rather than from reactions taking place at defect sites. [Copyright &y& Elsevier]

Abstract: CO hydrogenation is carried out on Co/CNT and CoRe/CNT catalysts at 483K, 1.85bar, H2/CO=10. The study addresses a fundamental understanding of the effects of reaction conditions (syngas pressure, temperature and GHSV) and Re promotion on the Co activity and selectivity by SSITKA. A systematic SSITKA study was performed to gain a better understanding of the surface reactions at different conditions by measuring the surface concentrations of CO and CH x intermediates on Co. The TOFs of CO conversion and methane formation are found to be sensitive to H site coverage, which is affected by the competitive adsorption between H2 and CO. Higher temperature mainly increases the reaction rate constant, which changes more significantly as compared with the site coverage of the H and CO. CO pressure and temperature have more significant effect on the methane selectivity than H2 pressure. Re has little effect on the TOF and selectivity of the Co/CNT catalyst. SSITKA experiment reveals that both NCO and increase slightly with Re promotion. The surface coverage of CO is about ten percent higher on the Re promoted sample, suggesting that Re might be able to enhance CO adsorption a little bit. However, Re promotion does not change the intrinsic site activity and apparent activation energy. The apparent activation energy for methane formation is found to be about 118kJ/mol for both promoted and unpromoted catalysts. [Copyright &y& Elsevier]

Abstract: We report an investigation of the formation mechanism of a gold (Au) thin-film electrode made by electroless deposition for in situ electrochemical (EC) attenuated-total-reflection surface enhanced infrared adsorption spectroscopy (ATR-SEIRAS). The Au thin film was generated via galvanic electroless deposition from [Au(S2O3)2]3− precursor and consisted of ∼46nm Au nanoparticles (NPs) deposited on Si infrared window. The observation of v(Au–S) (263cm−1) and v(S–S) (454cm−1) on the freshly deposited Au film using surface enhanced Raman spectroscopy (SERS) confirmed that the initial adsorbed sulfur species was S2O3 2−. Subsequent acid-treatment broke the S–S bond and yielded Au surface-bound atomic sulfur species. EC stripping of them led to the formation of (bi)sulfate identifiable by in situ EC ATR-SEIRAS. A sulfur coverage of 0.5 was estimated. We also discovered that square-wave treatment of the Au film led to significant surface reconstruction and much enhanced oxygen reduction reaction (ORR) activity. We attribute the latter to the reconstruction-caused new sites that could stabilize better the adsorbed ORR intermediates for facilitating the subsequent reaction step(s). [Copyright &y& Elsevier]

Abstract: The CO2 capture properties of a new nanocrystalline CaO-based mixed oxide (CaCeZrO x ) were studied in both TGA and a fixed bed reactor. The kinetics of CO2 capture at dry conditions was compared between these two reactors. The application of the new CO2 acceptor in sorption enhanced steam methane reforming was studied by a fixed-bed reactor in the presence of 40wt% nickel hydrotalcite catalysts. Experimental results show that the new CO2 acceptor, CaCeZrO x has a significantly improved CO2 capture capacity and cyclic reaction stability compared to natural dolomites, because of the large pores and stable backbone structure. It has also been observed that the sorption enhanced steam methane reforming in the fixed bed reactor produces more than 95% H2 in a single-step process. Increase in production of hydrogen and higher CO2 capture capacity are also observed with an increase in the residence time of methane. Steam has a significant effect on the stability of the acceptors, but not very much on the kinetics and capacity of CO2 capture. The capacity of CO2 capture on the acceptors in the SESMR process cannot be predicted by the independent CO2 capture kinetic study on acceptor alone. A synergy effect between the sorption enhanced reactions and CO2 capture on the CO2 capture capacity was observed on the all solid CaO based CO2 acceptors. [Copyright &y& Elsevier]

Abstract: Objective: A self-organizing map (SOM) is a competitive artificial neural network with unsupervised learning. To increase the SOM learning effect, a fuzzy-soft learning vector quantization (FSLVQ) algorithm has been proposed in the literature, using fuzzy functions to approximate lateral neural interaction of the SOM. However, the computational performance of FSLVQ is still not good enough, especially for large data sets. In this paper, we propose a suppressed FSLVQ (S-FSLVQ) using suppression with a parameter learning schema. We then apply the S-FSLVQ to MRI segmentation and compare it with several existing methods. Methods and materials: The proposed S-FSLVQ algorithm and some existing methods, such as FSLVQ, generalized LVQ, revised generalized LVQ and alternative LVQ, are compared using numerical data and MRI images. The numerical data are generated by a mixture of normal distributions. The MRI data sets are from a 2-year-old female patient who was diagnosed with retinoblastoma of her left eye, a congenital malignant neoplasm of the retina with frequent metastasis beyond the lacrimal cribrosa. To evaluate the performance of these algorithms, two criteria for accuracy and computational efficiency are used. Results: Comparing S-FSLVQ with FSLVQ, generalized LVQ, revised generalized LVQ and alternative LVQ, the numerical results indicate that the S-FSLVQ algorithm is better than the other algorithms in accuracy and computational efficiency. Moreover, the proposed S-FSLVQ can reduce the computation time and increase accuracy compared to existing methods in segmenting these ophthalmological MRIs. Conclusions: The proposed S-FSLVQ is a good competitive learning algorithm that is very suitable for segmenting the ophthalmological MRI data sets. Therefore, the S-FSLVQ algorithm is highly recommended for use in MRI segmentation as an aid for supportive diagnoses. [Copyright &y& Elsevier]

Abstract: The mechanism of bubble growth has been of particular interest for decades due to its significant contribution to understanding boiling heat transfer. In present work, a visualization experiment was carried out to analyze the bubble growth in a vertical rectangular narrow channel by using water as working fluid under 1 and 3bar system pressure. The bubble growth in various experimental conditions was obtained by analyzing the recorded pictures. Results show that bubble growth and bubble size are significantly affected by mass flux, heat flux and system pressure, and also by the nucleation site density. To obtain a well prediction for bubble growth, a dual model is proposed in this paper. This model is comprised of a linear model for the inertia controlled stage of bubble growth and a power law model for the heat diffusion controlled stage of bubble growth, and the prediction of the dual model agrees well with the experimental result with an error less than ±15%. [ABSTRACT FROM AUTHOR]

Abstract: Of concern is the following Cauchy problem for fractional integro-differential equations with time delay and nonlocal initial condition where , , is a generator of a solution operator on a complex Banach space , the convolution integral in the equation is known as the Riemann–Liouville fractional integral, representing the delay property, is a function, and is an operator defined from into for some which constitutes a nonlocal condition. The local existence and uniqueness of mild solutions for the Cauchy problem, under various criteria, are proved. Moreover, we present an existence result of the global solution. Also an example is given to illustrate the applications of the abstract results. [Copyright &y& Elsevier]

Abstract: We report the solubility of carbon dioxide in four physical solvents and compare our data to predicted phase behavior using the conductor-like screening model for real solvents (COSMO-RS) formalism. The solubility data are presented in pressure-composition (Px) diagrams as well as Henry''s law coefficients on a wt% basis at 298.15K. The oligomers presented in this study are poly ethylene glycol di-methyl ether (PEGDME), perfluoro polyether (PFPE), poly di-methyl siloxane (PDMS), and poly propylene glycol di-methyl ether (PPGDME), which is a new solvent designed for this application by our group. These oligomers had 2–5 repeat units. We assess these four oligomers for capturing CO2 from high-pressure streams. The COSMO-RS formalism is able to qualitatively and to some extent quantitatively describe solubilities of CO2 in each of the oligomers. [Copyright &y& Elsevier]

Abstract: First-principles calculations based on density functional theory (DFT) have been used to investigate the reaction mechanism of dry methane reforming on Ni(111). The most energetically favorable adsorption configurations of the species involved in this process are identified and the transition states for all the possible elementary steps are explored by the dimer method. Then, the related thermodynamic properties at 973.15K are calculated by including the zero-point energy correction, thermal energy correction and entropic effect. It is found that CO2 dissociates via a direct pathway to produce CO and O dominantly, and atomic O is revealed to be the primary oxidant of CH x intermediates. Based on this information, two dominant reaction pathways are constructed as both the CH and C oxidation are found to be likely. The reaction network begins with the dissociation of CO2 and CH4, and then the generated CH and C are oxidized by atomic O to produce CHO and CO, followed by the CHO decomposition to finally generate CO and H2. As for these two reaction pathways, the oxidation step is predicted to determine the overall reaction rate under the current investigated conditions, while the CH4 dissociation is found to be the rate-limiting step at lower temperatures. [Copyright &y& Elsevier]

Objective: To determine the spermicidal activity of antisemen antibodies in the hamster model.Design: Prospective, controlled study.Setting: Advanced preclinical sciences center.Animal(s): Subgroups of 10 and 14 golden hamsters.Intervention(s): Ex vitro and in vivo treatment of sperm with antisemen antibodies or normal rabbit serum.Main Outcome Measure(s): The EC(50) value of antisemen antibodies, the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies, the average sperm mitochondrion fluorescence intensity, the rate of fertilization, and the scoring of histologic changes in the hamster vaginal tissue.Result(s): The EC(50) value of antisemen antibodies was found 70 microg/mL, and the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies (at 70 microg/mL) was 5 minutes; for the experimental and control groups, the average fluorescence intensities of sperm mitochondria were respectively 180.28 +/- 82.24 and 309.74 +/- 148.37, the fertilization rates in vitro were 0.09% and 45%, the rates of fertilization with intrauterine sperm injection were 0 and 15.0%. There was a significant difference between two groups. None of the four hamsters that received antisemen antibodies in gel-polyoxyl-40-stearate had epithelial disruption characteristic of inflammation.Conclusion(s): Antisemen antibodies possess appreciable spermicidal potential, which may be explored as an effective constituent of spermicide. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work was to gain a better understanding of the influence of Sn on the dispersion of Pt in platinum supported SBA-15 catalysts and thereby on the dehydrogenation of propane (DHP) activity, selectivity to propylene, coking and catalyst stability. To this end, DHP over Pt-SBA-15 and Pt-Sn-SBA-15, prepared by incipient wetness impregnation (IW), was studied at 793K by means of tapered element oscillating microbalance (TEOM) coupled with on-line gas-chromatography. This allowed us to determine simultaneously the comprehensive information from a single catalysis experiment. The catalysts were characterised by N2-physisorption, transmission electron microscopy (TEM-EDXS), X-ray diffraction (XRD) and H2-chemisorption, which revealed that the presence of Sn results in higher Pt dispersion by the formation of Pt–Sn alloy. It is evident from TEOM studies that after 220min on stream the amount of coke formed is almost three times higher over Pt-Sn-SBA-15-IW than on its counterpart Pt-SBA-15-IW, albeit the former exhibits considerably higher propane conversion, superior selectivity to propylene and stability than the latter. It is demonstrated that propane conversion and coke formation on the catalysts can be correlated with Pt particle size. A modified drain-off effect is proposed to explain the superior selectivity and stability of the bimetallic than the monometallic catalyst. [Copyright &y& Elsevier]

In the present study, an evaporative cooling test system consisting of an elliptical-heat exchanger was examined. Tests were conducted for various airflow rates of 52, 68, 81, 96 Cubic Meter per Minute (CMM), sprinkler water flow rates of 30, 40, 50 Liter per Minute (LPM), and hot water flow rates of 18, 22, 28 LPM. The sprinkle nozzle types and outside wet-bulb temperatures were also investigated. The convective heat transfer of the sprinkle water film outside the tubes and the mass transfer between air and water film on tube bundles were probed. The film thickness and sprinkle water picture were studied using high-speed cameras and image processing techniques. The results show that the mass transfer performance of the evaporative cooler was enhanced with the growth of the airflow rate. When the sprinkler water flow rate rose to 50 LPM, the heat-mass transfer coefficient of the evaporative cooler decreased since the water film on the tube was thickened. The low hot water flow rate at the tube side (18 LPM) resulted in a superior performance due to a high local temperature and improved local mass transfer. The experimental data were used to obtain empirical correlations for the heat coefficient of the liquid film and mass transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon content and surface area of the products were significantly reduced under CO 2. • The vaporization of Cu was accelerated with MgCl 2 at 900 °C under CO 2. • The removal of Zn under CO 2 was lower than that under N 2. • The composition of P bearing phases could be affected by CO 2 at 900 °C. • Pyrolysis under CO 2 enhanced P recovery and reduced bioavailability in the product. Although swine sludge (SS) contains a high level of phosphorus (P) and has the potential to be used as an ideal source to produce P-rich biochar, it has a high heavy metal content, especially Cu and Zn, which limits its use. Herein, the influences of temperature, MgCl 2 addition, and carrier gas on the removal of Cu and Zn and P recovery during SS pyrolysis were studied. The results indicated that the removal efficiencies of Cu and Zn exhibited different tendencies in the presence of CO 2 and N 2. The removal of Zn in N 2 was higher than that in CO 2 and increased at elevated temperatures; moreover, it was sensitive to chloride addition at 800 and 900 °C during pyrolysis under CO 2. The atmosphere had a significant effect on Cu removal. The maximum removal efficiency was only 27.91 % when SS was treated under N 2 , which remarkably increased after chloride addition under CO 2 at 900 °C, reaching 85.96 %. Additionally, the mineral phase compositions and transformations treated under different process conditions were investigated. Ca 5 (PO 4) 3 Cl and Mg 3 (PO 4) 2 were the main P-bearing phases in the sludge treated with chloride addition, irrespective of the atmosphere, except for the product obtained at 900 °C under CO 2 , in which Mg 3 (PO 4) 2 was replaced by Ca(PO 3) 2. The gradual transformation from magnesium phosphate to calcium phosphate during pyrolysis affected P recovery and bioavailability. Pyrolysis under CO 2 resulted in a higher P recovery rate and lower bioavailability in the products. [ABSTRACT FROM AUTHOR]

Abstract: A series of Ni2+–Fe2+–Al3+ hydrotalcite (HT) catalysts with varying compositions have been prepared by coprecipitation from Fe2+. The structure and properties of the catalysts were carefully characterized by various methods such as XRD, EXAFS, TGA, TPR, N2 adsorption/desorption, XPS and H2 chemisorption. It was shown that pure HT structures can only be prepared at low Fe2+ concentrations, while mixed oxide phases with spinel structure will form simultaneously at high Fe2+ concentrations. Pure HT structures are very important for small particle size, narrow size distribution and large surface area of the resulting catalysts. XPS study demonstrated Fe enrichment on the catalyst surfaces, which might have partly contributed to the low hydrogen chemisorption capacity for the Fe-containing catalysts. [Copyright &y& Elsevier]

Abstract: Carbon nanofibers (CNFs) were synthesized on a series of hydrotalcite (HT) derived Ni-Fe/Al2O3 catalysts in order to achieve optimization of quality and productivity. It was found that only the Fe catalyst is active in CO disproportionation and only the Ni catalyst is active in ethylene decomposition, whereas all catalysts are active in ethylene decomposition when the reactants are a mixture of C2H4/CO. The catalysts were characterized after CNF growth by XPS and EXAFS in order to understand the catalyst structural changes during CNF synthesis. The structure and properties of the as-synthesized CNFs were characterized by SEM, TEM, TPO and XRD to correlate the CNF structure and crystallinity with the catalyst composition and the nature of the gas precursors. Based on the experimental results a reaction mechanism was proposed. Moreover, it was demonstrated that Ni-Fe/Al2O3 catalysts derived from HT precursors are promising for controlled large-scale synthesis of CNFs. [Copyright &y& Elsevier]

Abstract: Studies on dehydrogenation of propane (DHP) over monometallic Pt-SBA-15 catalysts, which contain markedly different Pt particle sizes, reveal that the reaction is dependent on the size of the particle. Catalyst with smaller particles (∼3nm) is much more active and less selective than that with larger particles (∼21nm). Rate of coking, selectivity to coke formation and the amount of coke formed are significantly higher over the former than that on the latter. [Copyright &y& Elsevier]

Abstract: Typical floorplanning concerns a series of objectives, such as area, wirelength, and routability, etc., with various aspect ratios of modules in a free-outline regime. However, in a hierarchical design flow for very large ASICs and SoCs, a floorplan can be completely useless for a situation where its outline is dissatisfied. In this paper, we study the fixed-outline floorplanning problem that is more applicable to the hierarchical design style. We develop an efficient algorithm based on robust evolutionary search and achieve substantially improved success rate. We also propose a new approach to handle soft modules to further adjust the generated floorplan to fit into the prescribed chip outline. The effectiveness of our methods is demonstrated on several large cases of MCNC and GSRC benchmarks. [Copyright &y& Elsevier]

Abstract: A proper stacking design and cell assembly are important to the performance of fuel cells. The cell assembly will affect the contact behavior of the bipolar plates with the membrane electrode assembly (MEA). Not enough assembly pressure may lead to leakage of fuels, high contact resistance and malfunctioning of the cells. Too much pressure, on the other hand, may result in damage to the gas diffusion layer and/or MEA. The stacking design may affect the pressure distribution within the fuel cell stack and thus the interfacial contact resistance. Uneven distribution of the contact pressure will result in hot spots which may have a detrimental effect on fuel cell life. In this study, finite element analysis (FEA) procedures were established for a PEM single cell with point stack assembly method. The mechanical properties and geometrical dimensions of all the fuel cell components, such as bipolar plates, membrane, gas diffusion layer and end plates were collected for accurate simulation. From the FEAs, the compliance as well as the pressure distribution of the single cell was calculated. In order to verify the results of the analysis, experimental tests, with a pressure film inserted between the bipolar plates and the MEA, were conducted to establish the actual pressure distribution. Color variations of the pressure film could be calibrated to obtain pressure distribution. Compliance of the gas diffusion layer was also measured. The analysis procedures for the fuel cell stacking assembly were established by comparing the simulation results with those of the experimental data at various levels of assembly pressures. They can help determine the proper stacking parameters such as stacking design, bipolar plate thickness, sealing size and assembly pressure, and are important in obtaining a consistent fuel cell performance. [Copyright &y& Elsevier]

Abstract: Carbon nanofibers (CNFs) have been used as templates for manipulating the properties of Ni catalyst particles. Both incipient wetness impregnation and deposition–precipitation have been used to prepare the catalysts. Relatively well-dispersed Ni nanoparticles have been prepared on oxidised CNFs by incipient wetness impregnation. The diameter of the CNFs has been shown to have a significant effect in determining the Ni crystal size. In addition, CNFs are suitable templates to induce microstrain to metal particles. Such microstrain has significant effects on the activity of Ni crystals during ethane hydrogenolysis. This provides new opportunities to manipulate the crystal size and activity of the metal by selecting proper carbon nanofibers as support. TPO has been demonstrated as a powerful tool to study the CNF supported catalyst and to provide information on Ni loading and relative activity of NiO for CNF oxidation. [Copyright &y& Elsevier]

Abstract: Pre-reforming of natural gas has been studied on a nickel catalyst at 480–550°C and 20bar using a TEOM (Tapered Element Oscillating Microbalance) reactor. The focus has been on carbon formation and the main objective was to study the influence of C2–C3 hydrocarbons in the methane feed on carbon deposition on the catalyst. Coking thresholds for different mixtures of hydrocarbons were determined by varying the steam to carbon (S/C) ratio at various temperatures. The steady-state coking rate decreases with increasing S/C ratio, and increases with increasing carbon number of the hydrocarbon. Unsaturated hydrocarbons show a strong effect on coking rates and on carbon thresholds. For mixtures of methane and propane/propene, the steady-state coking rate as well as the coking threshold decreased with a decrease in the mole fraction of propane/propene and with an increase in the hydrogen mole fraction. The coking rate revealed a complicated temperature dependency, and a minimum in the coking rate and in the coking threshold was detected at 500°C. A relationship between the critical steam to carbon ratio and the thermodynamic carbon activity is also developed based on a suggested reaction mechanism, which can properly predict the role of hydrocarbon, hydrogen and water in carbon formation. [Copyright &y& Elsevier]

Abstract: Cu/CNF and Cu/CeO2/CNF catalysts have been synthesized and characterized on different nanostructured carbon nanofibers (CNF). The samples have been tested in isopropanol dehydrogenation. Cu/CNF show similar activity to Cu catalysts supported on activated carbon. Cu/CeO2 nanotubes have been synthesized on the CNF surfaces. The Cu/CeO2 nanotubes exhibit much higher activity and lower activation energy than Cu/CNF. The selectivity towards acetone depends on the fraction of CeO2 in the composites. High activity and selectivity has been achieved with a Cu12Ce5/CNF catalyst. [Copyright &y& Elsevier]

Abstract: A series of silica supported Fe catalysts were prepared by different methods in order to obtain varying Fe particle sizes. The catalysts were characterized by XRD, TPR, BET, and TEM. The CNT growth from CO disproportionation was studied in order to establish a relationship between the CNT growth rate and the particle size. We found that there is an optimum catalyst particle size at around 13–15nm which will lead to the maximum growth rate. The influence of the metal loading on the growth rate was also investigated. A CNT growth model has been formulated to explain the experimental results. [Copyright &y& Elsevier]

Abstract: Ab initio and CIS theories were employed to study a new type of perylenequinonoid photosensitizer (PQP)—hypomycin B (HMB), which has only one pair of adjacent hydroxyl group and carbonyl group in its peri-region. Geometries, Mulliken charge population, energy, and photophysical and photochemical process in excited state were discussed in detail. The results indicate that HMB exhibits quite similar intramolecular proton transfer (IPT) to perylenequinone, which offers an indirect understanding that the IPT process in perylenequinonoid derivatives (PQD) is a single proton transfer process. There exists the crossing of the potential energy surface of the singlet and triplet so that the intersystem crossing (ISC) can occur. The ISC will increase triplet quantum efficiency, which is the basis for photosensitization of PQP. [Copyright &y& Elsevier]

Abstract: The impact of some engineering aspects such as space velocity, catalyst metal loading, hydrogen, and temperature on carbon nanotube (CNT) production rate, productivity, and morphology in carbon monoxide disproportionation has been studied. The morphology and quality of the CNTs produced were examined by high resolution transmission electron microscopy (TEM). It was found that space velocity and metal loading have significant effects on the production rate and CNT productivity. The presence of H2 dramatically increased the productivity, but altered the CNT structure. The synthesis temperature also influenced the carbon productivity and structure. The results were interpreted according to the traditional model for CNT growth, and the implications for large-scale CNT production were suggested. [Copyright &y& Elsevier]

A highly novel method of direct synthesis of 2-aryl-3-sulfenylindoles in moderate to good yields was developed via one-pot tandem reaction of readily available α-aminocarbonyl compounds and catalytic amount of benzenamines with RSSR. Unlabelled Image • High total yield up to 94% • Simple condition • Stable raw material and broad [ABSTRACT FROM AUTHOR]

Aqueous phase reforming (APR) of ethylene glycol was performed at 225 °C and 30 bar in batch and continuous reaction conditions. The effect on the APR performance by functionalizing carbon supports with nitrogen and adding Mn to Pt-based catalysts was investigated. The presence of nitrogen species on the carbon surface and Mn-addition (PtMn) improved the catalytic activity and promoted H 2 production. XPS results suggest that the enhancement of the catalytic activity may be attributed to charge transfer from platinum to the nitrogen groups and Mn. Pt-based catalysts were stable under the studied reaction conditions, while up to 97 % of the manganese leached into the liquid solution during APR. However, the catalytic activity was maintained even with such significant decrease in Mn content, indicating that only a small amount of Mn is necessary to maintain the promotional effect on Pt during APR. [Display omitted] • Electronic interactions between Pt-N and Pt-Mn led to enhanced catalytic activity. • N-doped carbon nanofibers effectively improved H 2 yield in aqueous phase reforming. • Pt-based catalyst promoted with Mn presented higher H 2 yield and selectivity. • Metal-support interactions are key factors in promoting catalytic activity. [ABSTRACT FROM AUTHOR]

• Microkinetic analysis is used to screen perovskites for methane partial oxidation. • The catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3. • Bulk oxygen vacancy formation energy is identified as a single descriptor. • 667 combinations of A- and B-cations have been screened in terms of stability. • SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are identified as catalyst candidates. DFT calculations and descriptor-based microkinetic analysis have been performed to screen ABO 3 perovskite catalysts for methane partial oxidation. The scaling relations indicate the adsorption energies of H@O and CH 3 @B have the capability of representing the energetics of methane oxidation, and bulk oxygen vacancy formation energy is identified to be a better single descriptor of the kinetics. The resultant volcano-shaped plot shows the catalytic activity varies in the order LaMnO 3 > LaFeO 3 > LaCoO 3 ≈ LaCrO 3 , which agrees with the experimental findings and thus validates our theoretical predications. By screening 667 combinations of A- and B-cations based on electron neutrality, structural tolerance factors, and experimental verification, 77 ABO 3 have been identified to be stable. Of them, SrRuO 3 , SmRhO 3 , LaIrO 3 , NdRhO 3 , and BaOsO 3 are located at the summit of the volcano, which also exhibit satisfactory CO selectivity and enhanced carbon resistance compared to LaFeO 3 , and may act as the oxygen carrier candidates. [ABSTRACT FROM AUTHOR]

Catalytic conversion of cellulose to diols is an attractive approach in the valorization of biomass, because of the high atom efficiency of the reaction process. The work here highlights the potential of cellulose as a renewable feedstock to produce value-added chemicals, especially vicinal diols. The catalytic conversion of cellulose in water on Ni-Cu/4ZnO-CNT catalyst is discussed, with a focus on four main reaction pathways leading to the formation of C 2 , C 3 , C 4, and C 6 vicinal diols, involving hydrolysis, retro-aldol condensation, hydrogenation, isomerization, dehydrogenation, and thermal side reactions. By modifying the Ni-Cu bimetallic active sites, the pathways can be manipulated, resulting in selective retro-aldol condensation C-C cleavage, leading to a shift towards the selective production of either ethylene glycol (EG) or 1,2-propylene glycol (1,2-PG). Finally, we explore the optimization of reaction conditions to tune product selectivity. This study provides important insight into the catalytic conversion of cellulose and offers promising avenues to produce value-added chemicals from renewable feedstocks. [Display omitted] • Bimetallic NiCu/ZnO-CNT catalyst was proposed in direct cellulose conversion to diols. • Reaction pathway was built based on the kinetic studies. • Product selectivity can be tuned via varying the Ni-to-Cu ratio. [ABSTRACT FROM AUTHOR]

[Display omitted] • A zeolite structure descriptor (local framework disturbance index) is proposed. • LFDI guide design of titanosilicalites by matching Ti site and framework topology. • Beta framework exhibits lowest average substitution energy due to the lowest LFDI. • Beta framework showed the highest capacity of framework Ti species. • Ti-beta demonstrated outstanding 1-hexene epoxidation performances. Rational design of metal-containing zeolites with different framework topologies can boost catalytic performance, but the successful synthesis of metal-containing zeolites typically requires selection of suitable zeolite scaffolds. Herein, a zeolite structure descriptor (i.e., the local framework disturbance index, LFDI) is proposed to guide the design of Ti-containing zeolites by matching Ti sites and different framework topologies to enhance olefin epoxidation performance. Theoretical calculations of the incorporation of Ti metal atoms into different crystallographic T sites indicate that the BEA framework exhibits the more negative average substitution energy (-0.50 eV) than MFI and MEL frameworks due to the lowest average LFDI (3.14). As expected, the BEA framework showed the highest capacity of framework Ti species than MFI and MEL frameworks by atom-planting method. This high framework Ti content demonstrated outstanding 1-hexene epoxidation performances (TON: 1827.5). This work paves the way to rationally design Ti-containing zeolites by atom-planting method for epoxidation reactions. [ABSTRACT FROM AUTHOR]

Hydrogen is highly demanded in biorefinery, and hydrogen production from renewable sources is essential to produce truly green transportation fuels from biomass. The present work demonstrates experimentally the production of high pressure H 2 with high purity by pressure swing sorption enhanced steam reforming (PS-SESR) of the byproducts from biorefinery. Pure hydrogen was produced by one-pot high pressure sorption enhanced reforming of a mixture of acetic acid (AA), glycolaldehyde (Gl) and hydroxyacetone (Hy), as model of the byproducts obtained from biomass fast-hydropyrolysis, which is integrated in the H 2 Bioil process, aimed at producing liquid transportations fuels. SESR was performed using Pd/Ni-Co derived from a hydrotalcite-like material as catalyst and dolomite as CO 2 acceptor. Both thermodynamic analysis and experimental study revealed enhanced hydrogen purity but lower hydrogen yield at high pressure compared to atmospheric pressure. Moreover, a compromise between pressure and temperature is needed to get high purity and yield of hydrogen. A H 2 purity as high as 99.6 vol% can be obtained at atmospheric pressure and 550 °C, while a H 2 purity of 99.0 vol% can be reached at 5 bar and 600 °C. Under these conditions, the H 2 yield is of 92.3% at 1 bar and 92.6% at 5 bar. These results show that the SESR of the biomass-derived compounds is an efficient method for the production of highly pure, hot and high pressure hydrogen, which is required for the overall process studied. According to the thermodynamic analysis, and given that the process is performed at high pressure, a pressure swing decarbonation process is suggested for the sorbent regeneration. [ABSTRACT FROM AUTHOR]

Objective To explore the core mechanism of long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) in the regulation of multidrug resistance of pancreatic cancer cells. Methods mRNA levels of GAS5, miR-181c-5p and Hippo pathway related genes were detected by quantitative real-time PCR (qRT-PCR). Protein levels of MDR-1, MST1, YAP and TAZ were measured by western blot. Cell viability was detected by MTT assay. The combination between GAS5 and miR-181c-5p was confirmed by RNA pull-down and RNA immunoprecipitation (RIP) assay. We also established pancreatic cancer-bearing mice model and analyzed tumor volumes. Results Our data showed GAS5 expression was significantly down-regulated, miR-181c-5p expression was significantly up-regulated in pancreatic cancer cells. Besides, Overexpresson of GAS5 obviously inhibited cell viability, while GAS5 knockdown showed the opposite outcome. Additionally, we also found that GAS5 negatively regulated miR-181c-5p, and miR-181c-5p dramatically promoted pancreatic cancer cell chemoresistance through inactivating the Hippo signaling. GAS5 regulated chemoresistance and Hippo pathway of pancreatic cancer cells via miR-181c-5p/Hippo. Finally, we confirmed that overexpression of GAS5 inhibited tumor growth in pancreatic cancer-bearing mice model. Conclusion GAS5 regualtes Hippo signaling pathway via miR-181c-5p to antagonize the development of multidrug resistance in pancreatic cancer cells. [ABSTRACT FROM AUTHOR]

• A assessment framework of methanol production integrated with a hybrid hydrogen strategy is established. • To comprehensively utilize hydrogen, "balance points" are proposed and defined. • The detailed techno-economic-environment performance are calculated. • The novel hybrid hydrogen supply strategy shows superior performance. A techno-economic-environment assessment framework of methanol production from coal integrated with a hybrid hydrogen supply strategy is established, gathering an insightful perspective of its broad sustainability and providing an effectually hybrid green, blue, and gray hydrogen supply plan to evaluate its performance. Process simulation and life-cycle analysis indicate that coal to methanol integrated with reverse water gas shift using coal to hydrogen (CTM-RWGS-CTH) and CTM-RWGS with water electrolysis using wind energy process show relatively independent excellent technical and environmental performance, respectively. To comprehensively utilize hydrogen energy to realize process integration and intensification, "balance points" are proposed and defined. Moreover, eleven possible hybrid hydrogen supply modes are developed and analyzed. Results show that the quaternary H 2 supply strategy exhibits enormous economic advantages, 0.051 $/kg methanol. The "balance point" in the quaternary H 2 supply strategy is CTM-RWGS-CTH 13%, CTM-RWGS H 2 from CTH without carbon capture, utilization and storage 37%, CTM-RWGS H 2 from byproduct gas to hydrogen 16%, and CTM-RWGS H 2 from water electrolysis using wind energy process 34%. Our hybrid hydrogen supply strategy embraces the full potential role of emerging CTM-RWGS processes to achieve low-carbon consumption and cleaner production, which should prevail over purely unitary hydrogen resources. [ABSTRACT FROM AUTHOR]

• The size effects of Cu catalysts on the catalytic hydrogen combustion are revealed. • A balance between moderate Cu–Cu and Cu–O coordination numbers is suggested. • The high Cu–Cu coordination favors H H bond dissociation and O H bond formation. • The high Cu–O coordination gives rise to strong metal-support interactions and hinders reaction. The removal of excess hydrogen in a catalytic process is a safety measure, which should be incorporated into fuel cell technologies. In this study, the size effects of Cu catalysts on the catalytic hydrogen combustion are examined by investigating the impact of Cu–Cu and Cu–O coordination numbers. A distinct volcano-shaped trend in catalytic performance is observed, reaching its peak when the Cu loading is at 5 wt% with a reaction rate of 0.55 mol H2 ·mol Cu −1·min−1. It is found that the lower Cu loading leads to strong metal-support interactions and a high Cu–O coordination, whereas the higher Cu loading hinders reduction and increases the Cu–Cu coordination. DFT calculations emphasize the significance of Cu(1 1 1) facets in facilitating H H bond dissociation and O H bond formation. However, excessively large Cu nanoparticles limit catalytic activity due to the reduced active sites. As a result, the 5 wt% Cu/γ-Al 2 O 3 catalyst, which strikes a balance between Cu–Cu and Cu–O coordination numbers, exhibits the highest catalytic performance for this reaction. This study not only provides valuable insights into the size effects of Cu–based catalysts on hydrogen combustion, but also offers guidance for designing highly active Cu–based catalysts. [ABSTRACT FROM AUTHOR]

Cr(VI) contamination is widely recognized as one of the major environmental hazards. To address the problem of remediation of soil Cr(VI) contamination and utilization of waste peanut shells, this study comprehensively investigated the effects of peanut shell-derived biochar loaded with root exudates of hyperaccumulator Leersia hexandra Swartz on Cr(VI) reduction and microbial community succession in soil. This study confirmed that root exudate-loaded peanut shell biochar reduced soil pH while simultaneously increasing DOC, sulfide, and Fe(II) concentrations, thereby facilitating the reduction of Cr(VI), achieving a reduction efficiency of 81.8%. Based on XPS and SEM elemental mapping analyses, Cr(VI) reduction occurred concurrently with the Fe and S redox cycles. Furthermore, the microbial diversity, abundance of the functional genera (Geobacter , Arthrobacter , and Desulfococcus) and the metabolic functions associated with Cr(VI) reduction were enhanced by root exudate-loaded biochar. Root exudate-loaded biochar can promote both direct Cr(VI) reduction mediated by the Cr(VI)-reducing bacteria Arthrobacter , and indirect Cr(VI) reduction through Cr/S/Fe co-transformation mediated by the sulfate-reducing bacteria Desulfococcus and Fe(III)-reducing bacteria Geobacter. This study demonstrates the effectiveness of peanut shell biochar loaded with root exudates of hyperaccumulator Leersia hexandra Swartz to promote soil Cr(VI) reduction, reveals the mechanism how root exudate-loaded biochar shapes functional microbial communities to facilitate Cr(VI) reduction, and proposes a viable strategy for Cr(VI) remediation and utilization of peanut shell. [Display omitted] • Peanut shell biochar loaded with root exudates of L. hexandra facilitated Cr(VI) reduction. • Root exudate-loaded biochar enhanced Cr(VI) reduction by shaping microbial communities. • Cr(VI) reduction occurred concurrently with Fe and S redox cycles. • Root exudate-loaded biochar promoted indirect Cr(VI) reduction through Cr/S/Fe co-transformation. • Geobacter , Arthrobacter , and Desulfococcus are involved in Cr(VI) reduction. [ABSTRACT FROM AUTHOR]