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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]

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]

• 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]

Abstract: Cobalt based Fischer–Tropsch synthesis catalysts were studied by adsorption microcalorimetry. A series of catalysts consisting of 20wt% cobalt supported on γ-Al2O3 were examined. Cobalt particle size as evaluated by H2 chemisorption varied from 4.8 to 16.7nm in diameter. H2 and CO were examined as probe molecules and their adsorption on reduced cobalt catalyst was investigated. The results show only minor differences in the initial heat of adsorption for the studied catalysts, while at intermediate coverages (20–60%) the heat of adsorption appears to be nearly identical. [Copyright &y& Elsevier]

• 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]

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]

Abstract: In Part I of this article, we proposed a finite iterative algorithm for the one-sided and generalized coupled Sylvester matrix equations (AY − ZB, CY − ZD)=(E, F) and its optimal approximation problem over generalized reflexive matrices solutions. In Part II, an iterative algorithm is constructed to solve the two-sided and generalized coupled Sylvester matrix equations (AXB − CYD, EXF − GYH)=(M, N), which include Sylvester and Lyapunov matrix equations as special cases, over reflexive matrices X and Y. When the matrix equations are consistent, for any initial reflexive matrix pair [X 1, Y 1], the reflexive solutions can be obtained by the iterative algorithm within finite iterative steps in the absence of round-off errors, and the least Frobenius norm reflexive solutions can be obtained by choosing a special kind of initial matrix pair. The unique optimal approximation reflexive solution pair to a given matrix pair [X 0, Y 0] in Frobenius norm can be derived by finding the least-norm reflexive solution pair of a new corresponding generalized coupled Sylvester matrix equations , where . Several numerical examples are given to show the effectiveness of the presented iterative algorithm. [Copyright &y& Elsevier]

Abstract: Rh supported on Zr x Ce1−x O2–Al2O3 (x =1, 0.5, 0.25, 0) catalysts are studied for catalytic partial oxidation of methane to synthesis gas. Alumina based nanocomposites are prepared through a citrate mediated route by modifying the alumina support with cerium and zirconyl nitrates via a simple evaporation-drying or a spray drying method. The effect of the commercial alumina types and the preparation method on the structure and thermostability of the nanocomposites has been studied based on the characterization by XRD, Raman spectroscopy, DTA, TEM and nitrogen adsorption–desorption measurements. Evonik Aeroxide AluC based nanocomposites prepared by spray drying give the highest thermostability concerning the sintering and phase transformation of the composites. Rh with a 0.1 or 0.5wt.% loading is deposited on these nanocomposites by incipient wetness impregnation method. After calcination at 1173K for 5h, these nanocomposites supported Rh catalysts are tested in the fixed-bed reactor for methane partial oxidation. It is found that the smaller c-CeO2 crystal size in the nanocomposites, i.e. the higher oxygen vacancy concentration, would be responsible of the lower ignition temperature due to the enhanced reducibility, whereas the higher Rh dispersion would be responsible of the higher methane conversion and selectivity to synthesis gas. Additionally the Rh dispersion is found to be linked to the BET surface area. The stability of the nanocomposites is also studied under reaction conditions. [Copyright &y& Elsevier]

Abstract: A highly efficient sp3–sp3 carbon–carbon bond formation system was developed for the aerobic ruthenium-catalyzed oxidative cross-dehydrogenative coupling reaction between tertiary amines and sp3 C–H compounds in the presence of RuCl3/O2, thus giving the corresponding α-functionalized amines. Compared with the reported method, H2O2 or t BuOOH was replaced successfully by economical and facile oxygen as the oxidant. Three types of activated C–H bonds for pronucleophiles were evaluated in this system. All these features combined are in accordance with important prospective green chemistry aspects. [Copyright &y& Elsevier]

Abstract: The catalytic activity and stability in the water–gas shift reaction have been tested for Au-based catalysts prepared by deposition of Au from colloid solutions. The supports that have been used are TiO2, TiO2 supported on carbon nanofibres (CNF) and CNF. Thermal treatments of the samples show that the Au particle size depends on the support material and hence the interaction between the Au particles and the support. In situ X-ray absorption spectroscopic (XAS) measurements during the water–gas shift reaction show no changes in the first Au–Au coordination number for the catalysts containing CNF. Furthermore, improved short-time stability is obtained compared to the AuTiO2 catalysts. The improved stability is achieved by the CNF stabilising small TiO2 particles and hence prevent subsequent sintering of the Au particles. [Copyright &y& Elsevier]

Abstract: First-principles calculations based on density functional theory and the generalized gradient approximation have been used to study the adsorption and dissociation of CH4 on Ni(100) surface. The favored adsorption sites of H, CH3, and CH4 are identified by considering the energy and stability of various binding sites. H atoms prefer the fourfold Hollow sites, while CH3 species favors the Bridge site with one of the C–H bonds pointing towards the neighbor Ni atom. When H and CH3 are coadsorbed on Ni(100) surface, several stable configurations are found, in which the atomic H and CH3 species are adsorbed at the Hollow and Bridge site, respectively, because of their little energetic difference. Through the electronic and vibrational calculations, the C–H–Ni three-center bond is regarded as the key factor determining the CH3 adsorption. The CH4 dissociation on Ni(100) surface is investigated with three different CH4 orientations considered. The energy barriers are calculated to be 0.61, 0.61 and 0.62eV, corresponding to the CH4 molecules orientated with one, two and three C–H bonds pointing towards the surface, respectively. All calculated activation energies have been corrected by including zero-point energy and dispersion energy, and are in good agreement with the experimental result (0.61±0.02eV). Because the energy barriers for the different reaction pathways take similar values, the CH4 orientation has a minor effect on the reactivity. [Copyright &y& Elsevier]

[Display omitted] • Using UV–vis-NIR to analyze the kinetics of ethylene oxychlorination. • Co-promoter effect of alkali and alkali earth metals on ethylene oxychlorination. • Methods to design and predict the reaction rate and Cu2+ concentration for the steady-state. The comprehensive kinetic study for CuCl 2 /γ-Al 2 O 3 -based catalysts was performed to elucidate the co-promoter effect in the ethylene oxychlorination, one of the most significant industrial processes to produce vinyl chloride monomer. Kinetic analysis was performed separately by transient kinetic studies, taking account of the reduction and oxidation steps in the catalytic cycle. The promoter effects on ethylene oxychlorination were ascribed to their influence on the Cu2+ reduction or Cu+ oxidation in the catalytic cycle. The reaction rate-diagram was gained and used to predict the steady-state reaction rate and Cu oxidation state by an operando setup combing MS and UV–vis-NIR spectroscopy. The results indicated that the K-doped catalyst could greatly increase the reaction rate of the oxidation step, which gave rise to higher Cu2+ concentration on the catalyst. Mg-doped catalyst had a great effect on enhancing the reaction rate for the reduction step. K and Mg co-doped catalyst had the dual effect, both the reaction rate and Cu oxidation state were located between K and Mg mono-doped catalyst. The results of steady-state reactions indicated that the reaction rates were quite close with that predicated by the rate-diagram. Byproduct analysis during the steady-state was also performed, the results demonstrated that the co-promoted catalysts can also reduce the byproduct formation. The current study is expected to provide one way for exploring the potential benefits of co-promotion on CuCl 2 /γ-Al 2 O 3 -based industrial oxychlorination catalysts to improve the catalytic performance and understand the reaction further. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyethylenimine over mesoporous carbon spheres solid sorbent for CO 2 capture. • CO 2 capture capacity (3.22 mmol/g) was achieved on 62.5PEI/MCS-1.1. • PEI /MCS will be one of the ideal candidates for CO 2 capture in the future. A novel low-concentration CO 2 capture material (PEI/MCS) was developed by loading polyethylenimine (PEI) over mesoporous carbon spheres (MCS) with high porosity. The effects of pore structure, PEI loading, capture temperature, and promoters on CO 2 capture of PEI/MCS were studied. The MCS with perfect spherical morphology was successfully synthesized by a hard-template assisted reverse emulsion method. The pore structure of MCS was adjusted by tuning the ratio of silica to carbon (Si/C) in the precursors. With increasing the Si/C from 0.8 to 1.1, the pore volume of MCS increased from 1.25 to 2.68 cm3/g. The optimal PEI loadings depending on the pore volume of MCS were 45, 62.5, and 65 wt.% for MCS-0.8, MCS-1.1, and MCS-1.5, respectively. The highest CO 2 capture capacity (3.22 mmol/g) was achieved on 62.5PEI/MCS-1.1 at CO 2 partial pressure of 0.05 bar (5 vol.%, a typical concentration of the tail gas from natural gas power plant and natural gas processing plant) and temperature of 75 °C, outperforming most of the solid amine sorbents reported at similar condition. However, the cycling stability of PEI/MCS is poor at the capture-regeneration temperature of 75 °C. The promoters Span 80 and 1,2-epoxybutane did not show remarkable effect on the cycling stability of PEI/MCS at 75 °C. Decreasing the capture-regeneration temperature can significantly improve the stability of PEI/MCS and there is almost no CO 2 capacity loss (regeneration >99.5 %) when the temperature decreased to 50 °C. As a result of high CO 2 capacity and excellent regenerability and stability, PEI /MCS will be one of the ideal candidates for CO 2 capture in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Initiation and progress of carbon formation on alloy 601 surfaces captured. • Less carbon under infinite (I- a c) than under finite low carbon (FL- a c) activity. • Raman spectroscopy: different degree of ordering of the carbon formed. • CO only (I- a c): Thin Cr 2 O 3 surface scale stabilized; grain boundaries beneficial. • In synthesis gas (FL- a c): (Ni, Fe, Cr) 3 O 4 spinel redox process promotes carbon. Ni and Fe are excellent catalysts for carbon formation, and industrial alloys are therefore susceptible to metal dusting corrosion; a costly issue in e.g. synthesis gas manufacture. The objective of this work is to better understand the initial reaction phenomena leading to metal dusting, and thereby minimize the corrosion through optimum alloy selection and pretreatment. Pre-oxidized alloy 601 samples were subjected to carburizing gaseous environments at 750 °C, and carbon formation and surface oxide layer development were investigated by SEM, optical microscopy, AES and Raman spectroscopy. Thin (S)TEM/EDS cross-section lamellae were prepared by Focussed Ion Beam milling. Beyond the initial incubation period, less carbon is formed under 10% CO/Ar than under synthesis gas with finite low carbon activity. Cr 2 O 3 evolves as a thin surface oxide layer with only CO reacting and more ordered carbon develops with increasing exposure time. In contrast, oxidation yields (Ni, Fe, Cr) 3 O 4 spinel formation while the materializing carbon remains its disorder during prolonged exposure to synthesis gas. The metal dusting corrosion rate is hence lowered due to Cr 2 O 3 stabilization, while the spinel represents an unstable redox state that continuously yields new carbon. A fine-grained alloy surface structure is also found beneficial to the Cr 2 O 3 formation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The electronic structure of V 2 O 3 upon single-atom doping is examined. • A weak Lewis acid-base interaction is found to occur on the pristine surface. • The first dehydrogenation step is identified as the rate-limiting step for PDH. • Mn 1 -V 2 O 3 is suggested to be a good catalyst candidate for PDH. Vanadium-oxide-based catalysts have recently been found very promising for the catalytic dehydrogenation of propane. In this work, self-consistent density functional theory calculations have been performed to examine how the electronic structure of the V 2 O 3 (0001) surface is modified by single-atom doping and how the catalytic properties can be tailored to propane dehydrogenation. The structural stability of single-atom-doped V 2 O 3 (0001) surfaces is assessed by comparing the adsorption energies of single atoms with the cohesive energies of bulk metals. A weak Lewis acid-base interaction is found to occur on the pristine surface, which can be strengthened and weakened by substitution of single atoms for V and O, respectively. On these two types of oxide surfaces, single atoms act as promoters and active sites. The first dehydrogenation step is identified as the rate-limiting step by microkinetic analysis. On all the single-atom-doped surfaces, the activation energy for water formation is higher than that for hydrogen recombination, implying that reduction of the oxide surfaces is difficult to take place during the course of the reaction. If a compromise between the catalytic activity and catalyst selectivity is made, Mn 1 -V 2 O 3 is suggested to be a good candidate as the catalyst for propane dehydrogenation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Support effects exist on Cs/Al 2 O 3 catalyzed aldol condensation of MeOAc with HCHO. • The strong interaction promotes the dispersion of Cs on Al 2 O 3. • The composition of Cs species varies with the identity of Al 2 O 3. • A balance between acidic and basic sites contributes to the production of MA. In this work, the support effects on vapor-phase aldol condensation of methyl acetate (MeOAc) with formaldehyde (HCHO) over cesium catalysts are understood by the employment of Al 2 O 3 with different morphologies and crystal phases. The structural and electronic properties of these supported Cs catalysts are characterized by multiple techniques, such as XRD, HAADF-STEM, EDS-mapping, XPS, NH 3 -TPD and CO 2 -TPD. The Cs species are found to be highly dispersed on the Al 2 O 3 surfaces, and their compositions vary with the identity of Al 2 O 3. A combined catalyst characterization and testing results indicates a balance between acidic and basic sites, i.e., an acid-base synergy, for the production of MA: the excess acidic sites lead to the lower MA selectivity due to the promoted further condensation, while the excess basic sites with the lower MeOAc conversion due to the insufficient activated HCHO species. These insights could be valuable for the design and optimization of catalysts for this reaction. [ABSTRACT FROM AUTHOR]

Nanocrystalline ZnO/CNT with enhanced electrochemical reduction of CO 2 to syngas [Display omitted] • Faradaic efficiency of synthesis gas of more than 75% was achieved on small ZnO particles. • The H 2 /CO ratio can be tailored by the ZnO particle size. • DFT study revealed the ZnO surface stabilizes CO 2 * and COOH* intermediates, therefore more active for CO 2 activation. • ZnO is promising for electrochemical syngas production. Electrochemical reduction of CO 2 and H 2 O can provide a promising pathway to synthesis gas generation for renewable electric energy storage and fuel production with the closed anthropogenic carbon cycle. However, the lack of affordable highly active catalysts to activate the stable CO 2 and H 2 O molecules presents a substantial challenge. Here we report ZnO supported on nanocarbon as a cost-effective and active catalyst for selective conversion of CO 2 and H 2 O to predominately synthesis gas, with higher selectivity and activity compared to polycrystalline metal catalysts such as Ag and Cu. The H 2 /CO ratio can be tailored for different industrial processes by tuning the applied potential and the particle size of ZnO. Density functional theory calculations showed that the higher activity of ZnO is related to more significantly stabilized intermediates, CO 2 *, COOH, and CO* compared to Cu and Ag. Our results highlight a promising class of low-cost, abundant oxide as active electrocatalysts for synthetic fuel production from CO 2. [ABSTRACT FROM AUTHOR]

This study proposed a super thermal integrated process for CO 2 capture by using internal thermal integration to reduce the total energy efficiency loss of the power plant. [Display omitted] • Super thermal integrated adsorption carbon capture process (STILT) is proposed. • The detailed modeling steps for the novel STILT process are carried out. • The compared analysis of energy efficiency and capture costs are calculated. • The novel process shows superior techno-economic-environment performance. The heat-integrated solid adsorbent process exhibits the potential to become an energy-saving method for CO 2 capture. Here, a super thermal integrated process (STILT) for CO 2 capture is proposed based on our experimental data. The novel process strengthened the process of internal thermal integration and significantly improved the total energy efficiency. This study further takes the commercial MEA process as the benchmark for the multi-dimensional assessment (considering the techno-economic-environment). When CO 2 products are compressed to 110 bar, the energy efficiency of the STILT process and MEA process is 53.45 % and 48.8 %, and the energy consumption is 1.5 MJ/kgCO 2 and 3.41 MJ/kgCO 2. Without CO 2 compression, the energy efficiencies of the STILT process and MEA process are 55.3% and 50.61%. The energy consumptions are 0.82 MJ/kgCO 2 and 2.63 MJ/kgCO 2. Due to the combination of internal thermal integration and enhanced CO 2 circulation capacity, the capture costs of the STILT process are 25.8–34.94 €·t−1 CO 2 , which significantly outweigh the MEA process (43.3–55.07 €·t−1 CO 2). This exhibits the superior techno-economic-environment advantages of the STILT process. This study harbors tremendous referential significance for the design and scale-up of the industrial CO 2 capture process. [ABSTRACT FROM AUTHOR]

Sub-nanometer-sized Cu 6 and Au 6 clusters are stably anchored on the oxygen-deficient anatase TiO 2 surface, where Cu 6 -(V O)-TiO 2 shows high catalytic activity and satisfactory selectivity toward MG. [Display omitted] • The size and structure of stable Cu and Au clusters on TiO 2 are determined. • Oxygen vacancies can stabilize sub-nanometer-sized metal clusters. • Ti 5c and Cuδ+/Auδ- ions are coordinated to reaction intermediates. • The activity of Cu 6 -(V O)-TiO 2 (1 0 1) shows strong temperature sensitivity. • Cu-TiO 2 has good catalytic performance for DMO hydrogenation and MG production. The electronic structures of Cu-TiO 2 and Au-TiO 2 and their catalytic behaviors in the hydrogenation of dimethyl oxalate (DMO) have been studied by the stochastic surface walking-global neural network potential method, density functional theory calculation, and microkinetic analysis. Calculated results indicate that metal clusters on the pristine and oxygen-deficient TiO 2 are mostly coordinated to O 2c ions, and the defective surface may provide additional oxygen vacancies for Cu 6 and Au 6 cluster anchoring. It turns out that the interfacial Ti 5c and Cuδ+/Auδ- ions provide adsorption and hydrogenation sites for the reaction intermediates with unsaturated O and C atoms, respectively. The turnover frequency for DMO consumption is much higher on Cu-TiO 2 than on Au-TiO 2 , Cu(1 1 1), and Cu(2 1 1) at 443.15 K and 20 bar of total pressure. Given the satisfactory methyl glycolate (MG) selectivity, the Cu-TiO 2 catalyst has the potential to act as an excellent catalyst for the selective MG production. [ABSTRACT FROM AUTHOR]

Enhanced electrochemical reduction of CO 2 to syngas on CuZnOCNT catalyst. • Copper doping on ZnO shifts the ECR activity towards CO formation closer to the top of the volcano. • The optimal amount of copper is around 20 at% for CO formation from electrochemical reduction of CO 2. • Higher amount of Cu doping leads to metallic Cu segregation, resulting in higher H 2 evolution activity. • The 14Cu86ZnO/CNT catalyst shows best performance in terms of syngas (1:1 ratio) production at -0.9 V, better than Ag foil. Electrochemical CO 2 reduction is a promising method for the production of CO 2 neutral fuels and chemicals from renewable electricity. ZnO supported on CNT is a low-cost electro catalyst that can produce syngas from CO 2 and H 2 O. A rational catalyst design strategy for further improvement of the ZnO/CNT catalyst is to dope with copper to strengthen the binding energy of the CO intermediate, which could improve the activity. In this work, a series of CuZnO/CNT catalysts with intimate Cu and Zn contact and various Cu loadings are prepared. By varying the copper content we show that the synergy of copper and zinc improves the activity for CO formation, and the optimal copper content is 20 at%. On hydrogen evolution, the addition of copper has a two-fold effect. This reaction is enhanced by the reduced ZnO particle size obtained when copper is added, but at similar particle sizes of ZnO, a suppression is observed with increasing copper content as CO evolution is enhanced. Stability tests showed that pure ZnO phase is more stable than metallic copper on ZnO. Compared with polycrystalline silver, the CuZnO/CNT catalysts are more active for syngas formation at a useful CO: H 2 composition. This work demonstrates that the viability of DFT based rational design of electrochemical CO 2 reduction catalyst. By varying CuZnO composition as well as crystallite size, one is able to tune the electrochemical reduction activity towards CO and H 2 , and therefore achieve desired syngas ratio. [ABSTRACT FROM AUTHOR]

• Small Ni particles exhibit higher steam methane reforming activity than large ones. • The size-dependent activity of Ni catalysts is related to the surface-dependent activity. • Ni(2 1 1) is the most active surface for steam methane reforming. • Decreased Ni(2 1 1) surface fraction results in reduced Ni activity as size increases. Fundamental understanding of the size-dependent activity is essential to harness powers of the nanocatalysts. Here we report an experimental and theoretical study of the Ni particle size effect on activity of steam methane reforming (SMR) to achieve a better understanding of the size dependence of kinetic behavior at an atomic level. A kinetic study illustrated the higher forward methane turnover frequency on the smaller sized Ni particles. The size-dependent activity was well reproduced by microkinetic modeling on a truncated octahedron model with the kinetic parameters estimated by the improved unity bond index-quadratic exponential potential (UBI-QEP) and the Brønsted–Evans–Polanyi (BEP) relationship. Microkinetic modeling suggested that the size-dependent activity of Ni catalysts is associated with the surface-dependent activity. Much higher activity of Ni(2 1 1) than Ni(1 1 1) and Ni(1 0 0) accompanied by decreased Ni(2 1 1) surface fraction results in reduced Ni activity as particle size increases. The activity of Ni(1 1 1) is limited by high free energy barriers, while that of Ni(1 0 0) is limited by site blockage by C* and CH*. This work offers a feasible approach to gain insight into size-dependent activity and to aid rational catalyst design for SMR in which preparing extremely small Ni particles (≤6 nm) might be a good strategy. [ABSTRACT FROM AUTHOR]

• The "dimethylcyclopropane" pathway is dominant for 2-pentene isomerization. • The ring-opening step is the rate-determining step for the isomerization reaction. • Van der Waals interactions would change the scaling relations in zeolite catalysis. Periodic density functional theory (DFT) calculations have been performed to examine the monomolecular reaction mechanism for 2-pentene skeletal isomerization catalyzed by acidic zeolite Beta, Mordenite, and ZSM-5. The use of periodic models allows consideration and analysis of zeolite steric constraints that occur within zeolite microspores. Three different reaction pathways, the "dimethylcyclopropane" (DMCP), methyl shift, and ethyl shift mechanisms, have been considered. The DMCP mechanism which includes rearrangement of protonated cyclopropane is proposed as the dominant reaction pathway, and the ring-opening step determines the overall reaction rate. Comparison of the effective energy barriers for 2-pentene isomerization over the three different zeolites reveals that large 12-ring channels of Beta and MOR have little steric hindrance effect on 2-pentene isomerization while small 10-ring of ZSM-5 significantly increases the reaction activation energy. Calculated results also indicate that the adsorption heat of ammonia is a good descriptor for the reactivity of zeolites without taking into account long-range dispersive forces. In contrast, linear scaling relations cannot be obtained by using the BEEF-vdW functional because van der Waals interactions between zeolites framework and guest molecules affects the energetics of the isomerization reaction and changes the transition state energy scaling relation in zeolite catalysis. [ABSTRACT FROM AUTHOR]

• The reducibility and structural stability of LaMO 3 (M = Sc - Cu) are examined. • The first four LaMO 3 perovskites have very high oxygen vacancy formation energies. • The maximum possible oxygen deficiency in LaMO 3 (M = Mn - Ni) is 0.5. • LaCuO 3 can lose one lattice oxygen atom per formula unit before it is deactivated. Periodic density functional theory calculations have been performed to examine the effect of oxygen deficiency on the structural stability of Lanthanum-based perovskites (LaMO 3), where on-site Coulomb interactions have been addressed by an additional Hubbard-type term. Calculated results indicate that with the exception of LaFeO 3 , the oxygen vacancy formation energy (Δ E f o r m a t i o n , v a c ) of LaMO 3 (M = Sc - Cu) becomes less positive when moving across the first transition metal period. The first four LaMO 3 perovskites have very high oxygen vacancy formation energies and can hardly be reduced under mild conditions, while the other five perovskites exhibit a much greater reducibility. During the formation of the first oxygen vacancy in LaMO 3 (M = Mn - Cu), the nearest neighbor transition-metal cations serve as the primary acceptors of the electrons left behind. As oxygen atoms are further removed, square-based pyramidal and tetrahedral coordination geometries appear successively, and an abrupt increase in Δ E f o r m a t i o n , v a c is observed at a specific oxygen deficiency (δ), which defines the maximum possible δ in the perovskite structures. Under this definition, the M3+ cations (M = Mn - Ni) can be possibly reduced to M2+ while LaCuO 3 may lose at most one lattice oxygen atom per formula unit before it is deactivated. [ABSTRACT FROM AUTHOR]

• Novel small-sized mesoporous TS-1 (STS-1) is synthesized by SAC method. • Cost-efficient TPABr is used as template for STS-1 synthesis. • The effect of TPABr concentration of STS-1 is investigated. • The Au/STS-1 catalyst has good performance for propene epoxidation with H 2 /O 2. Designing cost-effective titanium silicalite-1 (TS-1) with enhanced mass transfer ability is of prime scientific and industrial importance. In this work, a novel small-sized mesoporous TS-1 (STS-1) material is first synthesized in cheap TPABr system using steam-assisted crystallization method. Compared with cheap microporous TS-1 prepared by classical hydrothermal method (HTS-1) with particle size of 950 nm, STS-1 shows mesoporous character of 13 nm and reduced average particle size of 590 nm. Moreover, effect of TPABr concentration is systematically investigated, and both of insufficient and overmuch TPABr concentrations are unfavorable because of low crystallinity and exorbitant price, respectively. Importantly, the catalytic performance of cost-effective Au/STS-1 for direct propene epoxidation with H 2 and O 2 is much better than that of Au/HTS-1, and comparable to the performance of the expensive Au/TS-1. By multi-characterizations and activation energy analysis, the underlying mechanism for the enhanced performance is further discussed. This work sheds new light on the design and synthesis of highly effective and cost-efficient TS-1 catalysts. [ABSTRACT FROM AUTHOR]

Highlights • Water-assisted O 2 activation to form active OH∗ intermediates is in equilibrium. • The OH∗ species-assisted C H bond cleavage of glycerol is the possible RDS. • The oxidation of the primary and secondary hydroxyl groups have similar mechanism. Abstract Fundamental understanding of heterogeneously catalyzed aerobic, base-free oxidation of glycerol is highly desirable for sustainable and highly efficient chemical synthesis. In this work, Pt/CNTs catalyzed base-free oxidation of glycerol is investigated by combining experiments, DFT calculations and kinetics analysis. The solvent effects and kinetic isotope effects measurements as well as DFT calculations reveal that water-assisted O 2 activation to form active OH∗ intermediates is not in rate-determining step (RDS) but in equilibrium. Then, Langmuir-Hinshelwood kinetic models are developed and fitted with the experimental data. The OH∗-assisted C H bond cleavage of glycerol is discriminated as the RDS for the two parallel oxidation pathways of glycerol via primary or secondary hydroxyl groups, where the former case exhibits lower activation energy. The insights revealed here could guide the design and optimization of this catalytic process to generate the targeted products. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is a critical element in soils, essential to plant growth. Long-term and intensively managed Lei bamboo (Phyllostachys violascens) stands are usually subjected to severe soil acidification and Mn activation. However, Mn migration from topsoil to deep soil induced by severe soil acidification was poorly recognized and studied. The distribution and changes of the total and the operationally defined Mn forms in soil profiles and its potential stress and environmental effect were investigated in a chronosequence of Lei bamboo stands (0, 2, 6, 11, and 16 years of stand age). The results showed that the Mn amount was significantly decreased in topsoil and accumulated in subsoil with the long-term and intensive fertilizer application. Soil exchangeable Mn and superphosphate extractable Mn demonstrated large different variation to total Mn, whereas their sum was largely higher than and highly correlated with 8-hydroxyquinoline (HQN) extractable Mn. Soil organic carbon, pH value, exchangeable bases, and soil redox simultaneously controlled soil Mn depletion. In conclusion, long-term and intensive fertilizer application leads to soil acidification and accelerated soil Mn depletion in bamboo stand soil, promoting Mn accumulation in bamboo shoots. [Display omitted] • Intensive fertilizer application caused bamboo stands acidification seriously. • Soil acidification accelerated Mn leaching and enriching in subsoil. • Severe acidification enlarged the risk of Mn enrichment in bamboo shoot. • Soil organic carbon, pH, and exchangeable bases and soil redox controlled soil Mn's leaching. [ABSTRACT FROM AUTHOR]

Although Cd accumulation varies among rice varieties is recognized, the underlying mechanisms are not well clarified. In this study, comparative transcriptome analysis were performed by hydroponic culture system with two rice varieties, Y1540 (high Cd accumulator) and Y15 (low Cd accumulator) under 20 μM Cd stress. Results revealed 17,320 differentially expressed genes (DEGs) in roots of Y15 (7,655 upregulated and 9,665 downregulated) and 17,386 DEGs in roots of Y1540 (8,823 upregulated and 8,563 downregulated) expose to 20 μM Cd stress. Gene ontology (GO) analysis enriched 24 and 26 terms in Y15 and Y1540 respectively, including 23 common terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed 27 and 28 significant pathways in Y15 and Y1540 respectively, with 19 common pathways. Different responses to Cd stress between cultivars were not only reflected in differently enriched GO terms and KEGG pathways but also in different DEGs of 23 common GO terms and significant sequences represented by p-values of 19 common KEGG pathways. Both cultivars resist Cd through common processes with different weights; hence glutathione metabolism, mineral absorption, biosynthesis of secondary metabolites, and degradation of aromatic compounds could be playing a more important role in Y1540, whereas ribosome biogenesis in eukaryotes, mismatch repair, aminoacyl-tRNA biosynthesis, and the cell cycle maybe playing a more important role in Y15. Weighted gene co-expression network analysis (WGCNA) showed that five and three modules were clustered in Y15 and Y1540, respectively, with yellow and brown modules in Y15 and brown modules in Y1540 being significantly related to Cd stress. Further analysis showed that most of hub genes in Y15 were related to signal transduction or transcription factors, while most of hub genes in Y1540 were related to binding, metabolic, and secondary metabolic processes, which demonstrated their different response patterns at transcriptomic level to Cd stress. [Display omitted] • Y1540 accumulated more Cd than that of Y15 in root. • Cd stress induced more up- and less down-regulated genes in Y1540 than Y15. • Both cultivars resist Cd through common pathways with different weights. • Y15 has transcription factor/signal transduction as core process in Cd resistance. • Y1540 use chelation/metabolic/compartmentalization as core process to resist Cd. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both size and support effects of Au catalysts are explored for MAL conversion. • The Au edge site is identified as the main active site for MMA generation. • A kinetics strategy for disentangling Au geometric and electronic effects is presented. The direct oxidative esterification of methacrolein (MAL) has drawn considerable attention as a promising route to produce methyl methacrylate (MMA). Here, we report a kinetics strategy to identify the active sites of Au catalyst for its disentanglement of geometric and electronic effects on this reaction. A series of Al 2 O 3 and CeO 2 supported Au catalysts are prepared by urea deposition–precipitation method, whose particle sizes are tailored by changing the vacuum-drying temperature. Their catalytic activity is correlated with Au particle size based on a crystal structure modelling, in which the Au edge site is identified as the main active site. The reduction in the valence electron population of Au 5 d states facilitates the adsorption of MAL, thus the positive core-level shift of Au 4f levels for each support gives rise to a higher production of MMA. This kinetics strategy could be extended to the design of other metal catalysts for this reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] For the explosive and strongly exothermic direct propene epoxidation with H 2 and O 2 to synthesize propylene oxide, maintaining uniform gas flow and moderate reaction in the packed bed reactor is of prime industrial and scientific significance. Herein, randomly packed beds of spherical particles were simulated with resolved particle 3D computational fluid dynamics (CFD) under industrial conditions. Effect of particle size (i.e., 6, 8 and 10 mm) on performance of gas-phase propene epoxidation was numerically simulated. The fluid flow and temperature fields were fully coupled to the species and reaction distribution, including reactions in the particles and on catalyst surface. Based on the results of velocity, pressure drop, temperature and species distribution, heat transfer together with catalytic performance inside the fixed bed reactor, it is found that PPD-6 (Packed Particle Diameter 6 mm) model has a more uniform flow distribution, higher thermal conductivity and a lower temperature compared with PPD-8 and PPD-10. In addition, as packed particle diameter increases, the heat transfer capacity reduces and the temperature rise increases. As a result, the maximum hot spot temperature for the PPD-6 model is about 3 and 8 K lower than PPD-8 and PPD-10 model, respectively. In addition, the PPD-6 model has a more uniform reaction rate within the particles compared with the PPD-8 and PPD-10 models due to short diffusion path and high mass transfer capacity. Therefore, the PPD-6 model shows superior safety together with optimum conversion and selectivity. This work harbors tremendous referential significance to the design and scale-up of industrial reactors for propene epoxidation. [ABSTRACT FROM AUTHOR]

Realizing large-scale electrochemical hydrogen evolution in alkaline and neutral media by robust and non-noble-metal heterogeneous catalysts is highly ambitious due to the sluggish reaction kinetics at low H + conditions. Herein, highly efficient hydrogen evolution reaction (HER) catalysts, comprising Ni, NiO clusters, and defective carbon, are successfully constructed via a facile and large-scale route. Multiple synchrotron radiation-based X-ray spectroscopic characterizations, combining high-resolution transmission electron microscopy measurements, indicate the formation of ternary interfacial superstructure with intimate interfacial coupling through abundant Ni O C bonds. Impressively, the optimized catalyst loaded onto the usual glass carbon electrode exhibits exceptional catalytic activities with overpotentials of 64 and 76 mV to reach 10 mA cm −2 in 1 M KOH and 1 M phosphate buffer solution (PBS), respectively, representing one of the best non-noble-metal HER electrocatalysts to date. Insights into the metal/oxide interfacial effects through density functional theory calculations reveal that the interface sites could efficiently lower the energy barrier of the rate-determining step (RDS), contributing to the fast reaction kinetics. This work not only provides comprehensive insights into interfacial feature of highly active HER catalysts but also broadens the fundamental understanding of interfacial effects toward HER catalysis. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are non-coding RNAs that function as post-transcriptional gene regulators and that play vital roles controlling lipid metabolism. miR-205 is an important miRNA related to adipogenesis and lipid metabolism. However, little is known about the potential role of miR-205-5p in genetically improved farmed tilapia (GIFT, Oreochromis niloticus ). In this study, we used miRanda software to search for potential miR-205-5p target genes and found a lipid-metabolism-related gene called acetyl-CoA carboxylase β ( ACACβ ). Quantitative real-time polymerase chain reaction data indicated that there may be a negative regulation relationship between miR-205-5p and ACACβ gene expression under HFD rearing. Using luciferase reporter assays, we verified the binding site of miR-205-5p in the 3′-untranslated region of the ACACβ mRNA. Furthermore, an in vivo functional analysis of miR-205-5p was performed by injecting GIFT juveniles with a miR-205-5p antagomir. Reduced levels of miR-205-5p in GIFT liver increased ACACβ mRNA expression 12 h post-injection. miR-205-5p suppression also increased fatty acid synthase and peroxisome proliferator-activated receptor-α mRNA levels 48 h and 120 h post-injection, respectively. Taken together, our results indicate that miR-205-5p negative regulates hepatic ACACβ mRNA expression, and may serve as an important regulator in controlling hepatic lipid metabolism in GIFT. [ABSTRACT FROM AUTHOR]

Orthotopic liver transplantation (OLT) has become an increasingly used treatment for end-stage liver disease. However, acute allograft rejection is still a problem in postoperative care of liver transplantation with immunosuppressive therapy and it can lead to allograft damage and harm the survival of liver transplantation patient. This work proposes to use data-driven approach to build a predictive model for acute rejection. We consider not only prediction accuracy, but also interpretability of the prediction outcome in building the predictive model, so that the medical staffs can identify how the prediction is induced from data. The experiments use the real data provided by liver transplantation intensive care unit (ICU) of Chang Gung Memorial Hospital, Taiwan. In this work, the data is from a medical center, in which the patient data ranges from 2004 to 2013, and the number of data records is approximately 2 million. To the best of our knowledge, this is the first work using a large-scale database to focus on liver transplantation and generate interpretable rules that could be used by medical staffs. We compare with several methods, including SVM, ANN and random forest, and the experimental results indicate that the proposed method is comparative, and provides interpretable results. Central to the proposed method is to consider interpretability, and the goal is to provide interpretable results for the medical staffs to make decisions. The proposed transformation algorithms belong to data-driven approaches, so they could be applied to other intelligent or expert systems. Moreover, the outcomes are presented in rule format, which could be used by medical staffs and other expert systems. [ABSTRACT FROM AUTHOR]

Pd nanoparticles encaged within an amine-functionalized metal-organic framework (MOF), Pd@NH 2 -UiO-66, was successfully prepared via one pot direct construction of the MOF framework, cooperative in situ metal precursor incorporation followed by on-site moderate reduction process. Because of its abundant of nanocages accessible through small pore windows, as well as excellent coordination capability of metal ions sites from the amine groups within the NH 2 -UiO-66 matrix, the Pd nanoparticles were homogeneously confined within its cavities. Intriguingly, the prepared Pd@NH 2 -UiO-66 exhibits a high catalytic activity and exclusive selectivity in the liquid-phase hydrogenation of 2,3,5-trimethylbenzoquinone (TMBQ) to 2,3,5-trimethylhydroquinone (TMHQ), a key vitamin-E intermediate in a short period under relatively mild reaction conditions. Additionally, this catalyst was recycled up to 8 times without significant loss in both activity and selectivity. Furthermore, reaction mechanism was investigated using dispersion corrected density functional theory calculations, suggesting that the superior performance of Pd@NH 2 -UiO-66 could be ascribed to the cooperation between the Pd nanoparticle and the amine-functionalized UiO-66. This MOF-based composite shows great potential as heterogeneous catalyst for the catalytic hydrogenation reactions due to its high stability, excellent catalytic properties, and simple preparation. [ABSTRACT FROM AUTHOR]

The activated carbon treated at different temperatures was performed as a catalyst for the oxidation of glycerol to glycolic acid. Heat treatment at suitable temperature could promote the enrichment of ester and carboxyl functional groups with strong electronegativity, which serves as the efficient active site for the glycerol oxidation. Therefore, the optimal AC-400 catalyst with more ester and carboxyl groups shows excellent catalytic activity (0.0039 mol/g Cat /h) and GLYOA selectivity (53.2%). [Display omitted] • The efficient oxidation of glycerol to glycolic acid was realized over heat treated activated carbon. • Heat treatment tuned the composition and electronic structure of oxygen-containing functional groups. • The ester and carboxyl functional groups with strong electronegativity enhanced the adsorption and activation of glycerol. Exploring efficient and cheap catalyst for the selective oxidation of glycerol to valuable carboxylic acids is a critical and complicated challenge. Herein, we innovatively realized the efficient oxidation of glycerol to glycolic acid over metal-free catalyst under mild conditions via carbon material defect engineering. Multiple characterizations revealed that the stepwise functionalization of active carbon caused by simple high temperature control is adopted to fine-tune the composition and electronic structure of oxygen-containing functional groups. Specifically, the abundant ester and carboxyl functional groups exhibit stronger electronegativity than the hydroxyl group, and this enhanced electronic coupling effect strengthens the adsorption of glycerol, thus improving the catalytic activity. Kinetic analysis and density functional theory calculations demonstrated that the oxygen-containing functional groups (mainly ester and carboxyl) could promote the C–H bond activation of RCH 2 O* intermediate and once C–C bond cleavage of glyceric acid, ensuring the high selectivity of glycolic acid (53.2% over AC-400 catalyst). We anticipate that this work could sheds some light on the application and design of more new type of carbon-based metal-free catalysts in the aqueous phase oxidation of various polyols. [ABSTRACT FROM AUTHOR]

In order to improve the degradation activity of β-glucosidase (CpBgl) from Coniophora puteana , the structural modification was conducted. The enzyme activity of mutants CpBgl-Q20C and CpBgl-A240S was increased by 65.75% and 58.58%, respectively. These mutants exhibited maximum activity under the same conditions as wild-type CpBgl (65 ℃ and pH 5.0), slightly improved stabilities compared that of the wild-type, and remarkably enhanced activities in the presence of Mn2+ or Fe2+. The V max of CpBgl-Q20C and CpBgl-A240S was increased to 138.18 and 125.14 μmol/mg/min, respectively, from 81.34 μmol/mg/min of the wild-type, and the catalysis efficiency (k cat / K m) of CpBgl-Q20C (335.79 min−1/mM) and CpBgl-A240S (281.51 min−1/mM) was significantly improved compared with that of the wild-type (149.12 min−1/mM). When the mutant CpBgl-Q20C were used in the practical degradation of different biomasses, the glucose yields of filter paper, corncob residue, and fungi mycelia residue were increased by 17.68%, 25.10%, and 20.37%, respectively. The spatial locations of the mutation residues in the architecture of CpBgl and their unique roles in the enzyme-substrate binding and catalytic efficiency were probed in this work. These results laid a foundation for evolution of other glycoside hydrolases and the industrial bio-degradation of cellulosic biomass in nature. [Display omitted] • Improved β-glucosidase mutants were obtained via site-directed mutagenesis. • The activity of CpBgl-Q20C and CpBgl-A240S was increased by 65.75% and 58.58%. • The molecular mechanism of improved activity was preliminarily elucidated. • CpBgl-Q20C and CpBgl-A240S effectively promoted biomass cellulose degradation. [ABSTRACT FROM AUTHOR]

The industrial methanol to olefin process over HZSM-5 zeolite is currently faced with a low propylene yield with one third of the products being paraffin and aromatic, implying the side reactions play an evident role. This work focused on the kinetic modeling of the side reactions in the methanol to propylene process over HZSM-5 (Si/Al = 200) following our previous works on the main reactions: methanol and olefin co-conversion and olefin interconversion. The experimental results show that C 2 –C 5 paraffins are mainly produced from the hydrogenation of corresponding olefins and aromatics from C 3 –C 5 olefins through oligomerization, cyclization and dehydrogenation in accordance with the hydride transfer mechanism. Methane comes from the cracking of both higher alkanes and methanol. A comprehensive kinetic model was then established by integrating the alkane and aromatic generation steps into our previous developed model for methanol and olefin conversion, and the calculated results agree well with the experimental data under the investigated feed composition and reaction temperature conditions. The further parameter studies show that the total yields of both paraffins and aromatics decrease with temperature but increase with the methanol concentration. [ABSTRACT FROM AUTHOR]

The finding that the MG selectivity increases and the DMO hydrogenation activity decreases with increasing the Ag nanoparticle size reveals the structure sensitivity of DMO partial hydrogenation. [Display omitted] • The structural sensitivity of DMO partial hydrogenation over Ag catalysts. • Ag stepped surfaces dominate the kinetics of the hydrogenation reaction. • The DMO consumption rate decreases with increasing the nanoparticle size. • The MG selectivity rises as the particle size changes from 5 nm to 10 nm. • A new strategy to ensure thermodynamic consistency of the reaction. Silver nanoparticles of different sizes have been synthesized to study their catalytic performance in dimethyl oxalate (DMO) partial hydrogenation to methyl glycolate (MG). Then, a detailed microkinetic analysis based on the results of DFT calculations has been performed to elucidate the origin of the observed size-dependent kinetics, where tabulated thermodynamic properties of gas-phase species are used to ensure the thermodynamic consistency of the reaction. Calculated results show that the turnover frequency for DMO consumption is much higher on Ag(2 1 1) than on Ag(1 1 1), suggesting the stepped surface dominates the kinetics. The hydrogenation of DMO on the two surfaces occurs along the same dominant reaction pathway, and the rate-determining step for the partial and deep hydrogenation of DMO is DMO and MG dissociation, respectively. The finding that the MG selectivity increases while the DMO hydrogenation activity decreases with the Ag nanoparticle size reveals the structure sensitivity of DMO partial hydrogenation. [ABSTRACT FROM AUTHOR]

The phase diagram, mechanical and thermodynamic properties of metallic Co are investigated extensively using first-principles calculations in conjunction with a quasi-harmonic Debye model. The simulations indicate that metallic Co is a ferromagnetic hcp ( ε ) structure at 0 K and 0 GPa, and transforms to a nonmagnetic fcc ( β ) structure at about 120 GPa under compression, the transition is consistent with the experimental results (crystallographic transition) and other theoretical calculations. Particularly, from the calculated Gibbs free energy, the phase boundary between the ferromagnetic hcp ( ε ) phase and the ferromagnetic fcc ( γ f ) phase is drawn, it is close to the conjecture of Yoo et al. (2000) (the phase boundary between the ferromagnetic hcp phase ( ε ) and the mixed phases ( ε + β / γ ) of the ferromagnetic hcp ( ε ) structure and the ferromagnetic or paramagnetic fcc ( γ ), or nonmagnetic fcc ( β ) structure) as well as the part of experimental data under high temperature and high pressure. The elastic constants of the ferromagnetic hcp- and fcc-Co under temperature are presented for the fist time in theory, they are in reasonable agreement with experiments at zero temperature and zero pressure, and decrease slightly with increasing temperature at V / V 0 = 1 or V / V 0 = 0.97 . In addition, the heat capacity C V , thermal expansion coefficient α and Grüneisen parameter γ for the ferromagnetic hcp- and fcc-Co are also acquired and predicted successfully in an extended temperature and pressure range. [ABSTRACT FROM AUTHOR]

In order to improve the catalytic efficiency of cellulase for more effective utilization of lignocellulose, a novel endoglucanase (CgEndo) from Colletotrichum graminicola was expressed by Pichia pastoris X33 and modified by site-directed mutagenesis. Two mutants, Y63S and N20D/S113T, with 62.31% and 57.14% increased enzyme activities were obtained, respectively. On this basis, their biochemical properties, kinetic parameters, structural information as well as the application in biomass degradation were investigated and compared with the wild-type CgEngo. The results indicated that the mutation Y63S and N20D/S113T resulted in an improvement of proximity between enzyme and substrate through conformational changes of the catalytic region, which might contribute to the higher enzyme activities and catalysis efficiency (K cat / K m) of Y63S and N20D/S113T. These findings laid important foundation for the further engineering of this endoglucanase and practical application in efficient degradation of cellulosic biomass in nature. [Display omitted] • Improved endoglucanase CgEndo mutants were obtained via site-directed mutagenesis. • The activities of Y63S and N20D/S113T were 62.31% and 57.14% increased, respectively. • Y63S and N20D/S113T could effectively promote natural cellulose degradation. [ABSTRACT FROM AUTHOR]

Highlights: [•] First direct evidence of pore blocking for the deactivation of Au/TS-1 catalysts. [•] Uncalcined TS-1 with blocked micropores has higher gold loading efficiency. [•] Au/TS-1-B catalyst exhibits enhanced stability for over 30h. [•] Au/TS-1-B catalyst prepared by DP method shows high PO formation rate. [ABSTRACT FROM AUTHOR]

Abstract: Previous investigations indicated that histamine receptor H4 (HRH4) played important roles in many aspects of breast cancer pathogenesis, and that the polymorphisms of HRH4 gene may result in expression and functional changes of HRH4 proteins. However, the relationship between polymorphisms of HRH4 and breast cancer risk and malignant degree is unclear. In the present study, we conducted a case–control investigation among 185 Chinese Han breast cancer patients and 199 ethnicity-matched health controls. Four tag-SNPs (i.e. rs623590, rs16940762, rs11662595 and rs1421125) of HRH4 were genotyped and association analysis was performed. Odds ratios (ORs) with 95% confidence intervals (CI) were used to assess the association. We found that the T allele of rs623590 had a decreased risk of breast cancer (adjusted OR, 0.667; 95% CI, 0.486–0.913; P =0.012) while the A allele of rs1421125 had an increased risk (adjusted OR, 1.653; 95% CI, 1.139–2.397; P =0.008). Further haplotype analysis showed that the CAA haplotype of rs623590–rs11662595–rs1421125 was more frequent among patients with breast cancer (adjusted OR, 1.856; 95% CI, 1.236–2.787; P =0.003). Additionally, polymorphisms of rs623590 and rs11662595 were also correlated with clinical stages, lymph node involvement, and HER2 status. These findings indicated that the variants of rs623590, rs11662595 and rs1421125 genotypes of HRH4 gene were significantly associated with the risk and malignant degree of breast cancer in Chinese Han populations, which may provide us novel insight into the pathogenesis of breast cancer although further studies with larger participants worldwide are still needed for conclusion validation. [Copyright &y& Elsevier]

Abstract: A series of Zr x Ce1−x O2–Al2O3 (x =0, 0.25, 0.5, 1) nanocomposites were prepared through a citric acid mediated route. The thermal stability of these materials was investigated by calcination at temperatures between 1173 and 1473K for a certain time. The nanocomposites were characterized by XRD, DTA, nitrogen adsorption–desorption measurements, Raman spectroscopy, TEM and SEM. It was found that coating Zr x Ce1−x O2 on the surface of Al2O3 could substantially enhance the thermal stability of the composites, as evidenced by preventing the formation of α-Al2O3. Rh/Zr x Ce1−x O2–Al2O3 catalysts were prepared by incipient wetness impregnation, followed by calcination at 1173K for 5h. The Rh dispersion was measured by volumetric H2-chemisorption. The effect of the catalyst support, the reaction temperature, the Rh loading and the gas hourly space velocity in the catalytic partial oxidation of methane was studied in a quartz fixed-bed reactor, concerning activity, selectivity and stability. The ignition and extinction behaviors of the reactor on different catalysts were also investigated showing that the ignition temperature depends significantly on the composition of the supports. It was observed that the presence of cerium in the composites would lower the ignition temperature and enhance the activities of methane partial oxidation and water gas shift reaction. [Copyright &y& Elsevier]

Abstract: First-principles calculations based on density functional theory have been performed to elucidate the reaction mechanism for ethylbenzene dehydrogenation and the role of CO2 in H removal. On the basis of the experimental information and theoretical prediction, three model surfaces with Fe-, ferryl- and O-termination are constructed to represent the active Fe2O3(0001) surface. The calculated results indicate that on all of the three surfaces the C–H activation in the methylene group followed by the dehydrogenation of the methyl group is kinetically more favorable. The energy barriers for ethylbenzene dehydrogenation are lowest on the O-terminated surface, but the generated styrene is adsorbed too strongly to be released. As CO2 decomposition and the formation of HCOO are hindered by the relatively high activation energies, CO2 cannot serve as the oxidant to recover the O- and ferryl-terminated surfaces to keep the redox cycle. At the steady state of the reaction the coupling mechanism dominates on the Fe-terminated surface, with the synergistic effect between ethylbenzene dehydrogenation and the reverse water–gas shift reaction. Since the energy barrier for the formation of COOH is comparable to that for H2 formation, both the one-step and two-step pathways are predicted to contribute to the coupling mechanism, although the former is more probable. [Copyright &y& Elsevier]