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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]

Through theoretical calculations and magnetostructural study of nine radical compounds that exhibit strong anti-ferromagnetic coupling strength, it is revealed preliminarily that the overlap integral between adjacent radicals short contact atoms is relevant to associated strong anti-ferromagnetic coupling strength. It is also confirmed that spin density and overlap integral between adjacent radical short contact atoms are the two major factors that dominate intermolecular strong anti-ferromagnetic coupling strength. The study also reveals that the factor of the overlap integral can replace the factors of both interatomic short contact distance and slippage degrees of π-π stacking. The study also reveals for the first time that the overlap integral changes with different short contact atom and different central coordinated atom. [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]

Contagious pustular dermatitis is an exanthematous zoonotic disease caused by the orf virus. Pandemic outbreaks of this disease cause great economic losses, while the pathogenesis of this disease still remains obscure. In this study, blood samples were collected from 628 asymptomatic goats across China for PCR-based virus detection. We detected the orf virus in the blood of asymptomatic goats. Moreover, the orf virus obtained from the blood of infected goats was infectious and induced typical symptoms of contagious pustular dermatitis after inoculation of uninfected dairy goats. In summary, our data provide evidence that asymptomatic animals may be carriers of orf virus. Our findings should contribute to elucidating the details underlying the pathogenesis of contagious pustular dermatitis. [ABSTRACT FROM AUTHOR]

We investigated the effects of heat stress on genetically improved farmed tilapia, focusing on metabolic and immune responses. Differences in blood parameters, serum biochemistry, muscle fatty acid composition, and microRNA (miRNA) expression were analyzed in fish under heat stress. Fish were exposed to heat stress at 35 °C and sampled at 0, 6, 12, 24, and 48 h after exposure and compared with a control group maintained at 28 °C. The results showed that red and white blood cell counts, hemoglobin levels, and hematocrit values tended to increase ( P  < 0.05) and reached their maximum levels after 24 h, then declined. Acute heat stress enhanced serum glucose, total protein, and total cholesterol levels, and muscle fatty acid components were also altered. Serum alanine aminotransferase (ALT) activity was significantly increased after heat stress for 6 and 12 h. Polyunsaturated fatty acids levels were increased after heat stress for 12 and 24 h, whereas levels of monounsaturated fatty acids decreased in response to heat stress. Expression of hepatic miR-1 and miR-122 was significantly upregulated, and expression of miR-10c was significantly increased ( P  < 0.05) only after heat stress for 48 h. Acute heat stress altered metabolism closely related to the immune system and the liver of tilapia. These findings contribute to a theoretical framework for tilapia breeding at high temperatures. [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]

Objective Cancer-IgG is a newly-discovered molecule, mainly derived from epithelial carcinoma cells and is significantly correlated with differentiation, metastasis, local invasion, and poor prognosis of many cancers. In our previous study we detected IgG expression in oral epithelial carcinoma, including salivary adenoid cystic carcinoma (SACC), using an IgG-specific commercial antibody. Here, we explored the correlation between cancer-IgG and clinicopathological features of SACC. Design A total of 68 human SACC tissue specimens and 2 siRNAs were used to analyze the correlation between cancer-IgG and extra domain A (EDA + )-containing fibronectin using the cancer-IgG-specific monoclonal antibody, RP215. Results We found an unexpected correlation between cancer-IgG and EDA + fibronectin, both of which showed aberrant expression in SACC tissue samples. Both were highly expressed in SACC with nerve invasion. In our previous study, EDA + fibronectin overexpression in SACC cells decreased N-cadherin expression. In the present study, we used SACC-83 cells, wherein EDA + fibronectin is overexpressed and cancer-IgG is knocked down. EDA + fibronectin expression was reduced with cancer-IgG knockdown, while cancer-IgG expression did not affect EDA + fibronectin overexpression. Furthermore, knockdown of non-B cell-derived IgG in SACC cells decreased cellular motility ( P < 0.05) as well as increased E-cadherin and alpha-smooth muscle actin levels. Conclusion The results suggest that cancer IgG potentially regulates EDA + fibronectin expression, thereby suggesting possible new therapeutic approaches for SACC. [ABSTRACT FROM AUTHOR]

Background Anterior cervical diskectomy and fusion with plate-screw construct has been gradually applied for multilevel cervical spondylotic myelopathy in recent years. However, long cervical plate was associated with complications including breakage or loosening of plate and screws, trachea-esophageal injury, neurovascular injury, and postoperative dysphagia. To reduce these complications, the zero-profile spacer has been introduced. This meta-analysis was performed to compare the clinical and radiologic outcomes of zero-profile spacer versus cage-plate construct for the treatment of multilevel cervical spondylotic myelopathy. Methods We systematically searched MEDLINE, Springer, and Web of Science databases for relevant studies that compared the clinical and radiologic outcomes of zero-profile spacer versus cage and plate for multilevel cervical spondylotic myelopathy. Risk of bias in included studies was assessed. Pooled estimates and corresponding 95% confidence intervals were calculated. Results On the basis of predefined inclusion criteria, 7 studies with a total of 409 patients were included in this analysis. The pooled data revealed that zero-profile spacer was associated with a decreased dysphagia rate at 2, 3, and 6 months postoperatively when compared with the cage-plate group. Both techniques had similar perioperative outcomes, functional outcome, radiologic outcome, and dysphagia rate immediately and at >1-year after operation. Conclusions On the basis of available evidence, zero-profile spacer was more effective in reducing postoperative dysphagia rate for multilevel cervical spondylotic myelopathy. Both devices were safe in anterior cervical surgeries, and they had similar efficacy in improving the functional and radiologic outcomes. More randomized controlled trials are needed to compare these 2 devices. [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]

• Vegetable oil by catalytic deoxygenation is an ideal alternative fuel. • Industrial production process and reaction mechanism were primarily introduced. • Kinetics and deactivation of catalytic deoxygenation were discussed. • The kinetic effects of operating parameters were discussed in detail. The second generation of biodiesel produced through catalytic deoxygenation of the vegetable oil has been considered as one of ideal alternative fuels for the traditional fossil diesel, which can deal with the energy crisis and environmental pollution problems. This review integrates the important concepts of chemical kinetics including reaction mechanism, kinetic model, reaction condition, deactivation mechanism, and materials chemistry to facilitate the implementation for producing second-generation biodiesel from laboratory to industrial production. The industrial production processes and related reaction pathways of the second-generation biodiesel from molecular and industrial standpoints were primarily introduced. This paper further discussed the kinetic effect of different kinds of reaction conditions for the deoxygenation process. Notably, the kinetic model of catalytic deoxygenation was also presented in detail. Moreover, common deactivation mechanisms were summarized and corresponding measures for prolonging catalyst lifetime were proposed to enhance the kinetic stability of the catalyst. This review aims to provide the chemical kinetic insights to boost the industrial deoxygenation of vegetable oils. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT calculations to examine the mechanism for 2‑heptene isomerization. • Understanding the product and transition-state shape selectivity in BEA and MFI. • The effect of zeolite framework on the distribution of isomerization products. Isomerization of n -alkanes is industrially applied to improve the octane number of gasoline. The origin of shape selectivity and influence of micropore confinement in this reaction have not been fully understood. In this work, periodic DFT calculations have been performed to examine the mechanism for n -heptene isomerization in H-BEA and H-MFI. Three reaction pathways, including the protonated cyclopropane, edged-protonated cyclopropane, and alkyl shift mechanisms, have been examined. It is found the formation of smaller di-branched isomers is determined by product shape selectivity, but that of relatively bulky isomers is kinetically relevant and can be accounted for by transition-state shape selectivity. [ABSTRACT FROM AUTHOR]

In this paper, we present a technique to fabricate normally off GaN-based high-electron mobility transistor (HEMT) by sputtering and post-annealing p -NiO x capping layer. The p -NiO x layer is produced by sputtering at room temperature and post-annealing at 500 °C for 30 min in pure O 2 environment to achieve high hole concentration. The V th shifts from −3 V in the conventional transistor to 0.33 V, and on/off current ratio became 10 7 . The forward and reverse gate breakdown increase from 3.5 V and −78 V to 10 V and −198 V, respectively. The reverse gate leakage current is 10 −9 A/mm, and the off-state drain-leakage current is 10 −8 A/mm. The V th hysteresis is extremely small at about 33 mV. We also investigate the mechanism that increases hole concentration of p -NiO x after annealing in oxygen environment resulted from the change of Ni 2+ to Ni 3+ and the surge of (111)-orientation. [ABSTRACT FROM AUTHOR]

• A facile and scalable approach for synthesis of Fe-based MOF MIL-88A(Fe) developed. • Our approach has the advantages of mild synthesis conditions and high MOF yield. • MIL-88A(Fe) exhibited an excellent performance for oxidation of cyclohexene with O 2. • Both free radical and Fe-mediated reaction pathways involved in aerobic oxidation. Herein, we reported a facile and scalable approach for the synthesis of Fe-based MOF MIL-88A(Fe) via a simple liquid-phase route at atmosphere pressure, and its application as a heterogeneous catalyst for the efficient aerobic oxidation of cyclohexene to value-added 2-cyclohexene-1-ol. Over 130 g of spindle-shaped MIL-88A(Fe) nanocrystals with high crystallinity, monodispersed particle size, and large specific surface area were easily synthesized per batch according to our method. The resultant MIL-88A(Fe) exhibited a high catalytic activity (conversion: 81%) with 70% selectivity for 2-cyclohexene-1-ol in the aerobic oxidation of cyclohexene with O 2 as the sole oxidant under mild reaction conditions (0.5 MPa of O 2 , 353 K for 8 h), outperforming the analogues reported in the literatures. The combined experimental and theoretical approach support the reaction mechanism of the oxidation of cyclohexene via both the free radical reaction pathway and Fe-mediated reaction pathway, resulting in the selective formation of 2-cyclohexene-1-ol. [Display omitted] [ABSTRACT FROM AUTHOR]

Using polydopamine as nitrogen-doped carbon precursors, adsorbent and reducing agent of HAuCl 4 , nitrogen and Au nanoparticle could be in situ doped and surface modified successively into/onto carbon spheres. The conductivity, electrons transfer ability, and electrocatalytic activity of carbon sphere were improved by the synergistic effect of surface modification with Au nanoparticle and nitrogen doping and then the sensitivity of this electrochemical sensor was enhanced. The synthesized nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. Based on the difference of adsorption rates and oxidation potentials, both nitrophenol isomers ( o -nitrophenol, m -nitrophenol, p -nitrophenol) and dihydroxybenzene isomers (hydroquinone, catechol, resorcinol) could be identified, separated successfully, and determined simultaneously by differential pulse voltammetry. This proposed method with wide linear range (0.05–600 μmol L −1 ) and low detection limit (24–98 nmol L −1 ) was successfully applied for simultaneous detection of nitrophenol and dihydroxybenzene isomers in wastewater and natural water. [ABSTRACT FROM AUTHOR]

Outer membrane proteins (OMPs) are a class of proteins that reside in the outer membrane of Gram-negative bacteria. OMPs act as epitopes and are potential vaccine candidates. Outer membrane protein N (OmpN) is a component of the outer membrane of Edwardsiella ictaluri ( E. ictaluri ). In a previous study, the OmpN1-, OmpN2-, OmpN3-encoding genes of E. ictaluri were cloned, and here they were expressed in Escherichia coli . Western blotting showed that these three proteins had molecular weights of ∼60 kDa. Channel catfish were immunized with recombinant OmpNs (rOmpNs) and then challenged with E. ictaluri . The results showed that rOmpN1, rOmpN2, and rOmpN3, as well as a mixture of all three proteins (in a ratio of 1:1:1) generated moderate immune protection (relative percentage of survival = 62.5, 62.5, 67.5, and 75%, respectively). In an agglutination antibody titer assay, fish antisera showed an antibody titer of 1:128. Furthermore, each of the proteins stimulated high levels of lysozyme activity. In addition, a real-time polymerase chain reaction analysis revealed significant up-regulation of immune-related genes encoding major histocompatibility complex class I (MHC I), MHC II, CD4L, tumor necrosis factor-α, and interferon-γ after 24 and 48 h of challenge, compared with the levels stimulated by phosphate-buffered saline. Taken together, we conclude that rOmpNs may elicit immune responses and generate protection against E. ictaluri in channel catfish. Thus, rOmpNs could be promising vaccine candidates against E. ictaluri . [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]

Many studies have investigated exposure biomarkers for high dose radiation. However, no systematic study on which biomarkers can be used in dose estimation through premature chromosome condensation (PCC) analysis has been conducted. The present study aims to screen the high-dose radiation exposure indicator in calyculin A-induced PCC. The dose response of multiple biological endpoints, including G 2 /A-PCC (G 2 /M and M/A-PCC) index, PCC ring (PCC-R), ratio of the longest/shortest length (L/L ratio), and length and width ratio of the longest chromosome (L/B ratio), were investigated in calyculin A-induced G 2 /A-PCC spreads in human peripheral blood lymphocytes exposed to 0–20 Gy (dose–rate of 1 Gy/min) cobalt-60 gamma-rays. The G 2 /A-PCC index was decreased with enhanced absorbed doses of 4–20 Gy gamma-rays. The G 2 /A PCC-R at 0–12 Gy gamma-rays conformed to Poisson distribution. Three types of PCC-R were scored according to their shape and their solidity or hollowness. The frequencies of hollow PCC-R and PCC-R including or excluding solid ring in G 2 /A-PCC spreads were enhanced with increased doses. The length and width of the longest chromosome, as well as the length of the shortest chromosome in each G 2 /M-PCC or M/A-PCC spread, were measured. All L/L or L/B ratios in G 2 /M-PCC or M/A-PCC spread increased with enhanced doses. A blind test with two new irradiated doses was conducted to validate which biomarker could be used in dose estimation. Results showed that hollow PCC-R and PCC-R including solid ring can be utilized for accurate dose estimation, and that hollow PCC-R was optimal for practical application. [ABSTRACT FROM AUTHOR]

The Single-Event MicroKinetic methodology has been successfully extended from Fe to Co catalyzed Fischer-Tropsch Synthesis. A total of 82 experiments were performed in a plug flow reactor with a H 2 to CO molar inlet ratio between 3 and 10, a temperature range from 483 to 503 K, CO inlet partial pressures from 3.7 to 16.7 kPa and space time varying between 7.2 and 36.3 (kg cat s) mol −1 . Via regression, statistically significant and physicochemically meaningful estimates were obtained for the activation energies in the model and the H, C and O atomic chemisorption enthalpies as required for the UBI-QEP method. A reaction path analysis allowed relating the observed deviations from the Anderson-Schulz-Flory distribution, i.e., a high methane and low ethene selectivity, to the symmetry numbers and a higher chemisorption enthalpy of the metal methyl species compared to the other metal alkyl species. Simulations at industrially relevant conditions show that, as a catalyst descriptor, the H atomic chemisorption enthalpy crucially determines both the CO conversion and the C 5+ selectivity. The higher FTS activity of Co compared to Fe is explained via the higher oxygen atomic chemisorption enthalpy on the latter compared to the former. [ABSTRACT FROM AUTHOR]

[Display omitted] • Substitution of transition metals for Cr increases the acidity of the adjacent O. • Linear scaling relations are established to identify the PDH activity descriptor. • High propylene selectivity of the M 1 -Cr 2 O 3 catalysts is achieved. • Cu 1 -Cr 2 O 3 is predicted to be the best catalyst for PDH among the 13 doped Cr 2 O 3. The catalytic behavior of M 1 -Cr 2 O 3 (M = Mn-Cu, Ru-Ag, and Os-Au) in propane dehydrogenation (PDH) has been studied by employing microkinetic modeling combined with results from periodic DFT + U calculations. Calculated results indicate that most of the single atoms concerned can be stably present on the Cr 2 O 3 surface. The adsorption energy calculations and Bader charge analysis demonstrate that the acidity of the O sites adjacent to the M sites would be enhanced upon doping, which in turn strengthens the atomic H adsorption and the co-adsorption of various PDH species. The surface H formation energy is identified as the reactivity descriptor for PDH over the M 1 -Cr 2 O 3 catalysts, and a volcano curve of the PDH activity is obtained. By calculating the difference between the propylene dehydrogenation and desorption barriers, it is found that some M 1 -Cr 2 O 3 catalysts show improved selectivity towards propylene, as compared to Cr 2 O 3. Comparison between the formation barriers of H 2 and H 2 O reveals that single-atom doping has no apparent negative effect on the catalytic stability of the Cr 2 O 3 surface. The Cu 1 -Cr 2 O 3 catalyst is finally identified as the most promising catalyst for PDH among the 13 M 1 -Cr 2 O 3 catalyst candidates, considering the catalytic activity, selectivity, stability, and cost. [ABSTRACT FROM AUTHOR]

[Display omitted] • A linear relationship for the activation energies and activation entropies existed over these catalysts. • Promoters altered the CO conversion rate by changing the surface CH x concentration. • The essence of change in product distribution is the alteration of carbon chain growth rate constant. The fundamentals of promoter effects in the Fischer − Tropsch synthesis over Co-based catalysts were systematically investigated by employing the Rh, Ir, Sb and Ga as promoters of Co/Al 2 O 3. Various characterizations showed the higher dispersion and reducibility over Rh- and Ir- promoted catalysts would cause a promoted adsorption property, while the Sb- and Ga- promoted catalysts showed a contrary result because the formation of alloy suppressed the accessibility of Co species. Based on the experimental results and kinetic calculations, a linear relationship for the activation energies of these catalysts as a function of activation entropies was proposed. Besides, steady state isotopic transient kinetic analysis (SSITKA) revealed that promoters mainly affected the surface CH x concentration to alter the CO reaction rate, and the chain growth rate constants would affect the product distribution. Since CoRhA and CoIrA greatly enhanced the CH x concentration and inhibited the chain growth ability, they owned a higher CO reaction rate and CH 4 selectivity. While the CoSbA and CoGaA suppressed the CH x concentration and intrinsic activity, but enhanced the chain growth ability, thereby revealing a lower CO reaction rate and CH 4 selectivity. Furthermore, the reactivity and selectivity difference were attributed to the modification of adsorption strength dictated by the enthalpy of activation on cobalt catalysts with different promoters. These findings provide kinetic insights into the promoter effects and pave the way for optimizing catalysts. [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 amount of Li 2 MnO 3 phase is affected by the coprecipitation conditions, synthesis temperature, and introduction of dopants. • LiCoMnO 4 cathode with less Li 2 MnO 3 phase exhibits better electrochemical performance. • Fluorination can suppress the phase decomposition and Li/Co ionic mixing during the redox process and increase structural stability, eventually causing LCMO-1.5F to demonstrate the best electrochemical performance. This study characterizes the relationship between synthesis conditions using the coprecipitation method and the structural/electrochemical properties of LiCoMnO 4. A cathode material, LiCoMnO 4 , prepared at pH 7.7 via coprecipitation and calcinated at 850 °C for 14 h achieved an initial discharge capacity of 114.6 mAh g−1 and a capacity retention rate of 71.3% after 20 cycles. To improve electrochemical performance, LiCoMnO 4 was doped with La, Mg, and F elements. The results showed that the strong ionic bonds of fluorination (M‒F; M =Li, Co, and Mn) can suppress the phase decomposition and Li/Co ionic mixing during the redox process and increase structural stability. Thus, LiCoMnO 4 doped with F demonstrated excellent electrochemical performance compared with that of the other dopants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A scaling relation-based L-H kinetic model is proposed to assess reaction rate. • Principles for making a kinetically consistent free energy profile are suggested. • Surface site coverages is estimated from free energy diagram of intermediates. • Reaction rate is straightforwardly obtained from the free energy diagram of reaction. • The model predicted resutls fit microkinetic modeling well for three model reactions. We report a scaling relation-based L-H kinetic model to assess reaction rate, where general principles for making a kinetically consistent free energy profile are suggested. Water-gas shift, Fischer-Tropsch synthesis, and steam methane reforming are employed as three model reactions to illustrate this approach. Herein, potential energies and free energies are calculated by improved scaling relations. The different methods to construct energy profiles are compared, and free energy diagrams rather than potential energy diagrams are more favorable to be employed in the field of reaction mechanism discriminations and kinetics investigations due to consisting of thermodynamic information. The sequence of various elementary steps is important to generate appropriate rate-determining step and rate expressions. It is suggested that the sequence of the elementary step follows a principle that the reaction step is set just before it is required, and desorption occurs just after the formation of the intermediates. Based on the procedure elucidated here, it is easy to get turnover frequency straightforwardly from the free energy diagram of reaction and the surface site coverages from the free energy diagram of intermediates. The scaling relation-based L-H kinetic model exhibits a similar accuracy for predicting the surface coverages and reaction rates with full microkinetic modeling toward all the three model reactions. It demonstrates that the approach proposed herein greatly simplifies the calculation but maintains high accuracy as compared to full microkinetic modeling. This approach can be widely applied for kinetic modeling to elucidate the reaction mechanism and kinetics for chemical processes of interest. [ABSTRACT FROM AUTHOR]

Our study developed the one-step catalytic cracking conceptual design using a two-stage riser reactor (OSCO). Molecular-level process models and multi-objective optimization strategies are also carried out. Results show that the OSCO process exhibits superior techno-economic, society, people's livelihood, and environmental performance. [Display omitted] • A novel process is proposed to crack naphtha, kerosene, diesel and heavy oil in the two-stage riser reactor efficiently. • A novel integration model of mixed fraction structure and molecular level is proposed. • The multi-objective optimization strategies using systematic solution algorithm are performed. • The novel process shows superior techno-economic, society, people's livelihood, and environmental performance. With the demand for vehicle fuels (i.e., gasoline and diesel) is expected to decline soon, crude oil to chemical technology exhibits great potential to drive the next industry transition. This megatrend has led to studies on maximizing the production of low-carbon petrochemicals at the cost of fuels, which requires aggressive ways of converting oil into chemicals in a clean and efficient pattern. Herein, we proposed a novel process, termed OSCO, to crack naphtha, kerosene, diesel and heavy oil in a two-stage riser reactor efficiently, which can perform several refining procedures in the two-stage riser reactor vessel. A novel integration model of mixed fraction structure and molecular level is proposed. The multi-objective optimization strategies are also carried out to solve the optimization problem. As a result, the OSCO process can stably convert untreated heavy Daqing crude oil into light olefins with total yields of ethylene and propylene over 33 wt%, which also exhibits superior techno-economic, society, people's livelihood, and environmental performance. These insights may have a positive pushing role in engineering design, process intensification, and the optimization of direct catalytic cracking of crude oil. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe and K were introduced into Pt/MOR catalysts to modulate the reactants adsorption in CO-PROX. • 1Pt0.1 K/Fe-MOR achieves 100% CO conversion and 60–70% CO 2 selectivity within 130–200 °C. • Fe improves the CO conversion by providing more oxygen vacancies to activate O 2. • K promotes the CO 2 selectivity by enhancing CO adsorption and weakening H 2 adsorption on Pt. Developing efficient and stable catalysts for preferential oxidation of CO (CO-PROX) within a wide temperature window is significant for the industrial hydrogen resource purification process. Herein, dual promoters of Fe and K were deliberately introduced to the mordenite supported Pt catalyst for optimizing the adsorption behaviors of reactants in CO-PROX. The optimal 1Pt0.1 K/Fe-MOR catalyst can achieve 100% CO conversion and 60–70% CO 2 selectivity (the ratio of CO/O 2 is 1:1) under the realistic application temperature range (130–200 °C), and remains catalytically stable during 65 h testing at 140 °C. A combination of detailed characterizations and density functional theory (DFT) simulations show that Fe species can avoid the co-adsorption of O 2 on the Pt sites by providing more oxygen vacancy to activate O 2 , while K species will further enhance the adsorption of CO and repulse the adsorption of H 2 on Pt surface. Therefore, the optimized adsorption of CO, O 2 and H 2 results in a total CO conversion and high CO 2 selectivity in high temperature range. [ABSTRACT FROM AUTHOR]

Eight undescribed 3,4- seco -norlabdane diterpenoids, callnudoids A–H, as well as two known analogues were isolated from the leaves of Callicarpa nudiflora. The structures were elucidated using spectroscopic methods and were compared with published NMR spectroscopic data. The absolute configurations of callnudoids D and E were defined based on ECD data or single-crystal X-ray diffraction. Callnudoids A–C are the highly modified labdane diterpenoids featuring rearranged 3,4- seco- ring and the formation of an undescribed cyclohexene moiety via C2–C18 cyclization. They only contain 15 carbon atoms on the carbon skeleton. Callnudoid D represents the unusual 3,4- seco -15,16-norlabdane diterpenoid with C13–C17 cyclization, and a putative biosynthesis pathway for callnudoids A, B, D, and E was proposed. All compounds were evaluated for their anti-inflammatory activities by inhibiting the lipopolysaccharide (LPS)-induced nitric oxide (NO) released in RAW264.7 cells; callnudoids A–E and H, and methylcallicarpate obviously inhibited pro-inflammatory cytokines TNF- α and IL-1 β in a dose-dependent manner. Eight undescribed 3,4- seco -norlabdane diterpenoids were isolated from the leaves of Callicarpa nudiflora , and some of them showed anti-inflammatory activity. [Display omitted] • Eight undescribed 3,4- seco -norlabdane diterpenoids were identified. • Callnudoids A–C feature a new cyclohexene moiety by C2–C18 cyclization. • A putative biosynthesis pathway for callnudoids A, B, D, and E was proposed. • Methylcallicarpate had significantly decreased levels of TNF- α and IL-1β. [ABSTRACT FROM AUTHOR]

In this work, the conductance of molecules with different alkyl length between benzene and carboxylic acid at each side are explored by electrochemical jump-to-contact STM break junction. The results show that the quantum interference (QI) is found in meta- phenylenedipropionic acid containing two methylene groups between benzene ring and carboxylic acid, and there is no obvious QI effect for meta -phthalic acid and meta -phenylenediacetic acid with shorter alkyl between benzene and carboxylic acid. We attribute the disappearance of the QI in meta -phthalic acid and meta -phenylenediacetic acid to the strong interaction between the benzene ring and anchoring group when they are too close. The current result reveals the importance role of alkyl chain on benzene ring and anchoring group in QI effect. [ABSTRACT FROM AUTHOR]

Soil degradation is an increasing threat to the sustainability of agriculture worldwide. Use of biochar from bio-wastes has been proposed as an option for improving soil fertility, degraded land restoration, and mitigating the greenhouse gas emissions associated with agriculture. Over the past 10 years, there have been hundreds of research studies on biochar from which it may be possible to determine appropriate methods for use of biochar to improve sustainable agriculture. To address potential gaps in our understanding of the role of biochar in agriculture, in this paper are reviewed the studies of 798 publications of field-, greenhouse- and laboratory-based biochar amendment soil experiments conducted as of August, 2015. Here we report the findings from a quantitative assessment. The majority of published studies have been performed in developed countries in soils that are less impaired than those found in many developing countries. The majority of the works involves laboratory and greenhouse pot experiments rather than field studies. Most published studies on biochar have used small kiln or lab prepared biochars rather than commercial scale biochars. And, most studies utilize wood and municipal waste feedstocks rather than crop residues though the later are often available in agriculture. Overall, the lack of well-designed long-term field studies using biochar produced in commercial processes, may be limiting our current understanding of biochar’s potential to enhance crop production and mitigate climate change. We further recommend greater alliance between researchers and biochar production facilities to foster the uptake of this important technology at a global scale. [ABSTRACT FROM AUTHOR]

Fuel-cell grade H 2 has been produced by the sorption enhanced steam reforming (SESR) of acetic acid, a model compound of the bio-oil obtained from the fast pyrolysis of biomass. A Pd/Ni–Co catalyst derived from a hydrotalcite-like material (HT) with dolomite as CO 2 sorbent was used in the process. A fixed-bed reactor with three temperature zones was employed to favor the catalytic steam reforming reaction in the high-temperature segment, the SESR reaction in the intermediate-temperature part, as well as the water-gas shift (WGS) and CO 2 capture reactions in the low-temperature segment. Different conditions of pressure, temperature, steam/C molar ratio and weight hourly space velocity (WHSV) in the feed were evaluated. Higher steam/C molar ratios and lower WHSV values facilitated the production of H 2 and reduced the concentrations of CH 4 , CO and CO 2 in the produced gas. A fuel-cell grade H 2 stream with a H 2 purity of 99.8 vol.% and H 2 yield of 86.7% was produced at atmospheric pressure, with a steam/C ratio of 3, a WHSV of 0.893 h −1 and a temperature of 575 °C in the intermediate part of the reactor (675 °C in the upper segment and 425 °C in the bottom part). At high pressure conditions (15 atm) a maximum H 2 concentration of 98.31 vol.% with a H 2 yield of 79.81% was obtained at 725 °C in the intermediate segment of the reactor (825 °C in the upper segment and 575 °C in the bottom part). Under these conditions an effluent stream with a CO concentration below 10 ppm (detection limit) was obtained at both low and high pressure, making it suitable for direct use in fuel cell applications. [ABSTRACT FROM AUTHOR]

A single-step chemical vapor deposition method using simple gaseous precursors was employed to grow nitrogen-doped carbon nanofibers from Fe and Ni particles on the surface of expanded graphite (N-CNF/EG). Due to the high electronic conductivity of the expanded graphite the N-CNF/EG could be used as electrocatalysts without the need for harsh purification procedures. Electrochemical testing showed that the N-CNFs grown from Fe exhibited a notable activity for the oxygen reduction in both acidic and alkaline electrolyte, in addition to demonstrating a high durability with a well-preserved catalytic activity after 1600 cycles in O 2 -saturated 0.5 M H 2 SO 4 . Physicochemical characterization revealed the formation of N-CNFs with a bamboo-like structure, encapsulated Fe particles and high pyridinic nitrogen content. The combination of high ORR-activity, an easily scalable synthesis approach and a highly conductive support material makes N-CNF/EG a promising oxygen reduction catalyst for low temperature fuel cells. [ABSTRACT FROM AUTHOR]

Purpose This paper discussed the influence of microstructure of emulsion membrane on O/W emulsion stability. Methods O/W emulsions were emulsified with equal dosage of egg yolk lecithin and increasing dosage of co-emulsifier (oleic acid or HS15). The average particle size and centrifugal stability constant of emulsion, as well as interfacial tension between oil and water phase were determined. The microstructure of emulsion membrane had been studied by 1 H/ 13 C NMR, meanwhile the emulsion droplets were visually presented with TEM and IFM. Results With increasing dosage of co-emulsifier, emulsions showed two stable states, under which the signal intensity of characteristic group (orient to lipophilic core) of egg yolk lecithin disappeared in NMR of emulsions, but that (orient to aqueous phase) of co-emulsifiers only had some reduction at the second stable state. At the two stable states, the emulsion membranes were neater in TEM and emulsion droplets were rounder in IFM. Furthermore, the average particle size of emulsions at the second stable state was bigger than that at the first stable state. Conclusions Egg yolk lecithin and co-emulsifier respectively arranged into monolayer and bilayer emulsion membrane at the two stable states. The microstructure of emulsion membrane was related to the stability of emulsion. [ABSTRACT FROM AUTHOR]

Hydrous hydrazine has received increasing attention as a promising hydrogen carrier owing to its many favorable attributes, such as high hydrogen content, low material cost, stable liquid state at ambient conditions, and free of solid decomposition byproduct. Herein, we report the synthesis of a supported core–shell structured Ni@Ni–Pt/La 2 O 3 catalyst by a combination of co-precipitation and galvanic replacement methods. The catalyst exhibits high catalytic activity and 100% selectivity towards hydrogen generation from hydrous hydrazine at mild conditions, which outperforms most reported hydrous hydrazine decomposition catalysts. The favorable catalytic performance of the Ni@Ni–Pt/La 2 O 3 catalyst is correlated with the Pt-induced electronic and geometric modifications on the catalyst surface. [ABSTRACT FROM AUTHOR]

For direct propene epoxidation with H 2 /O 2 , TS-1 with blocked micropores (TS-1-B) is recognized as an attractive support for Au catalysts with enhanced stability and activity by suppressing the deactivation caused by micropore blocking. In this work, as a consecutive effort, effect of Si/Ti molar ratio of TS-1-B on catalytic performance is investigated. It is shown that the optimum Si/Ti molar ratio is 40. In other words, both lower and higher ratios are unfavorable for the formation of propylene oxide, which are possibly attributed to the presence of extra-framework Ti species and the difficult transmission of hydroperoxide species from Au surface to nearby Ti sites, respectively. Based on this, effect of Au loading on catalytic performance is further examined. When the Au loading is 0.13 wt%, the catalyst shows not only high PO formation rate of 158 g PO h −1 kg Cat −1 comparable to the reported best activity without adding promoters, but also significantly enhanced stability at 200 °C over 30 h. [ABSTRACT FROM AUTHOR]

To investigate the role of steam on the structure and activities of platinum-based catalyst, a tin modified Pt/γ-Al 2 O 3 catalyst was prepared for propane dehydrogenation in the presence of steam. The propane conversion could be prominently elevated by nearly twofolds with only 1.0% loss of selectivity to propene when an optimum amount of H 2 O was added. The retarding effects of steam on the activities are also observed at higher H 2 O/C 3 H 8 molar ratios (>1). Kinetic studies results show that the apparent activation energies for steam dehydrogenations are lower than those without steam addition. The fresh, spent and steam pretreated catalysts were characterized by TG, Raman, H 2 -chem, HAADF-STEM, XPS and CO adsorption FT-IR (CO-FTIR). It is observed that the platinum particles sizes are smaller in the samples subjected to certain period of steam pretreatment. The changes of platinum dispersion in steam conditions are related to the changes of tin oxidation states and the segregation of platinum from Pt–Sn alloys, as revealed by CO-FTIR and XPS results. More accessible Pt sites that are generated in the steam due to the phase transformation of Pt–Sn catalyst as well as the removal of coke accumulated on the catalyst surface would account for the increase of catalytic activities and the decrease of activation energies in steam atmosphere. Competitive adsorption of H 2 O and other reagent over Pt sites would lead to the retarding effects of steam on the activities at high H 2 O partial pressure. [ABSTRACT FROM AUTHOR]

Four new phenolic acids, clerodens A–D ( 1 – 4 ) possessing an unusual bicycle [2.2.2] octane moiety were isolated from the whole plants of Clerodendranthus spicatus . Their structures were elucidated by extensive spectroscopic methods, including NMR, MS, and ECD data. All isolates were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7, and compound 4 showed significant inhibitory activities with IC 50 value of 6.8 μM. [ABSTRACT FROM AUTHOR]

In this paper, an analytical model of the critical heat flux (CHF) on the downward facing curved surface for pool boiling has been proposed, which hypothesizes that the CHF on the downward facing curved is composed of two parts, i.e. the evaporation of the thin liquid film underneath the elongated bubble adhering to the lower head outer surface and the depletion of supplement of liquid due to the relative motion of vapor bubbles along with the downward facing curved. The former adopts the Kelvin–Helmholtz instability analysis of vapor–liquid interface of the vapor jets which penetrating in the thin liquid film. When the heat flux closing to the CHF point, the vapor–liquid interface becomes highly distorted, which block liquid to feed the thin liquid film and the thin liquid film will dry out gradually. While the latter considers that the vapor bubbles move along with the downward facing curved surface, and the liquid in two-phase boundary layer enter the liquid film that will be exhausted when the CHF occurs. Based on the aforementioned mechanism and the energy balance between the thin liquid film evaporation and water feeding, and taking the subcooling of the bulk water into account, the mathematic model about the downward facing curved surface CHF has been proposed. The CHF of the downward facing curved surface for pool boiling increases along with the downward facing orientation except in the vicinity of bottom center region, because in this region the vapor bubble almost stagnates and the evaporation of the thin liquid film is dominant. In addition, the subcooling has significant effect on the CHF. Comparing the result of this model with the published experimental results show good agreement under the both of saturated and subcooled boiling conditions. [ABSTRACT FROM AUTHOR]

To study the possible impacts of dietary methionine hydroxy analogue (MHA) on growth, intestinal antioxidant status, and intestinal microbiota in juvenile largemouth bass (LMB) Micropterus salmoides (14.49–14.58 g), we conducted a feeding trial for 84-days. Four hundred and eighty fish were randomized into four dietary MHA treatments (0.0, 3.0, 6.0, and 9.0 g/kg diet). Results revealed that dietary MHA supplementation: (1) dramatically improved growth of juvenile LMB; (2) markedly decreased intestinal protein and lipid peroxidation, and increased intestinal antioxidant activities via Keap1/Nrf2 axis; (3) increased the richness and diversity of intestinal microbial community; (4) changed intestinal microbiota composition, increased the abundances of Proteobacteria , Bacteroidetes , and Actinobacteria , and decreased the abundances of Firmicutes and Cyanobacteria at the phylum level; increased the abundances of Bifidobacterium and Bacillus and decreased the abundance of Bacteroides at the genus level. Collectively, dietary MHA supplementation has potential benefits in growth, intestinal antioxidant capacity, and intestinal microbiota in LMB. The dietary optimal Met level of LMB (14.49–131.06 g) was recommended to be 14.49 g/kg diet, corresponding to 8.30 g/kg diet sourcing from basic diet and 4.19 g Met/kg diet sourcing from MHA based on specific growth rate. • Dietary methionine hydroxy analogue improved growth in juvenile largemouth bass. • Dietary methionine hydroxy analogue enhanced intestinal antioxidant capacity via Keap1/Nrf2 axis. • Dietary methionine hydroxy analogue have positive effects on intestinal microbiota. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trisphloroglucinol triazine (TPT) based HCPs were produced via a facile route. • Multiple interactions enable HCP-TPT-1 to effectively adsorb various OMPs. • Excellent adsorption performance for various OMPs were achieved. • A low-cost adsorbent with excellent adsorption performance and recyclability. The development of practical and efficient adsorbents is of great significance to the wastewater treatment. Here, we demonstrated trisphloroglucinol substituted triazine (TPT) as an intriguing building block to construct hypercrosslinked polymers (HCPs) for the removal of organic micropollutants (OMPs) from water. HCP-TPTs (HCP-TPT-1 and HCP-TPT-2) were facilely obtained via Friedel-Crafts alkylation of TPT with external crosslinkers, and possessed hierarchical porous structure, high degree of functionality, and good hydrophilicity. The embedded TPT skeletons in the porous structure help in effective adsorption of various cationic and nonionic OMPs. The maximum adsorption of HCP-TPT-1 reached 2336 mg g−1 for the rhodamine B, 2239 mg g−1 for the crystal violet, 521 mg g−1 for the 1-naphthylamine, and 500 mg g−1 for the 2-naphthol. In addition, the pseudo-second-order rate of HCP-TPT-1 for rhodamine B is 9.341 g mg−1min−1, which is superior to those adsorbent materials reported so far. Furthermore, HCP-TPT-1 can be easily reused at least seven times without obvious decrease of adsorption efficiency, indicating its potential application in wastewater treatment. [ABSTRACT FROM AUTHOR]

This paper proposes a high-efficient crisscross optimization (CSO) solution to the multi-area economic dispatch (MAED) in both centralized and decentralized optimization manners. First, the CSO is first employed to solve the complex MAED problem by using two powerful search operators including horizontal crossover and vertical crossover. Second, a unique distributed crisscross optimization (DCSO) is put forward to address the MAED problem in a fully decentralized optimization manner, aiming to protect the data privacy, reduce the solving dimensions, and alleviate the heavy communication burden. Under the decentralized framework, the proposed DCSO allows several separate CSOs across the network to optimize the operation of each generation area in parallel. Third, the CSOs assigned to different generation areas are all implemented by multi-agent system that provides the underlying framework of communication between generation areas, which contributes to achieving the independent and asynchronous optimization in each area while minimizing the total operational cost of the entire multi-area power system. Finally, the proposed approach is validated on three different cases. The experimental results verify the superiority of the CSO over other methods in solving the conventional MAED problem and confirm the effectiveness of the proposed DCSO in solving the decentralized MAED problem. • The CSO is first employed to solve the complex centralized MAED problem. • The DCSO is proposed to address the MAED in decentralized optimization manners. • The distributed CSO approach is implemented in multi-agent system. • The MAS-based optimization framework has advantage in protecting the data privacy. • The proposed approach is validated on three cases with different generation areas. [ABSTRACT FROM AUTHOR]

Transition metals such as Fe and Ni are the most commonly used catalysts for the growth of carbon nanofibers (CNFs) via CCVD method, and they always remain in the raw products. Much attention has been paid to purify CNFs, i.e., to remove residual metal particles and supports, before their use in most cases. However, some recent studies show that the residual metal particles usually attach at the tips of CNFs, and exhibit a different shape in comparison with the initial metal catalysts and as a result unique catalytic performance. The present review focuses on the state-of-the-art of the developments of synthesis of reshaped Fe and Ni particles at the tips of CNFs and their catalytic applications in cellulose conversion, selective hydrogenation and ammonia decomposition. In particular, effects of catalyst support, carbon source and its concentration, reaction temperature and etching gas are discussed. Moreover, the carbon adsorbates induced effect is highlighted as one of the key factors governing the reshaping of Fe and Ni particles. [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]

The commercial Kureha carbon was used as adsorbent for the selective adsorption of CO 2 over N 2 and CH 4 . The single-component isotherms are reported at pressures up to 2500 kPa and at 298, 310, and 323 K. The Langmuir–Freundlich model appropriately describes the adsorption equilibrium data over the whole range of conditions. The extracted isosteric heat of adsorption of CO 2 on Kureha carbon is significantly lower than those on zeolite NaX and some metal–organic frameworks that are considered to be promising candidates for CO 2 capture; this implies that the cost of regeneration with Kureha carbon can be potentially lower. The selective separations of two mixtures CO 2 /CH 4 and CO 2 /N 2 on Kureha carbon were experimentally investigated by a breakthrough-column technique. The simulations of transient breakthroughs for CO 2 /CH 4 and CO 2 /N 2 mixtures agree reasonably well with the experimental data. The breakthrough simulations also indicate that the separation performance is not significantly influenced by intra-particle diffusion resistances. Furthermore, the ideal adsorbed solution theory calculations are found to satisfactorily predict the experimentally observed separation performance. The investigations lead to the conclusion that Kureha carbon has a significant potential for CO 2 uptake from flue gas mixtures. [ABSTRACT FROM AUTHOR]

Adsorption of CTAB and HBr on Pt(100) in acid solutions were studied by using cyclic voltammetry (CV). The effects of bromide anion (Br − ), and cetyltrimethylammonium cation (CTA + ) together with Br − (CTAB) on the long-range ordered structure of Pt(100) were investigated systematically and analyzed quantitatively. It has demonstrated that adsorption of both CTA + and Br − can protect the long-range ordered structure of Pt(100). The upper limit potential of CV below which the long-range ordered structure of Pt(100) is starting to be disturbed was measured at 0.6 V in 0.1 M H 2 SO 4 , and it was shifted positively to 0.9 V in 0.1 M H 2 SO 4 + 1 mM HBr; this potential has been further postponed to even a higher potential of 1.1 V in 0.1 M H 2 SO 4 + 1 mM CTAB solution, demonstrating that the ability of protecting the long-range ordered structure of Pt(100) is CTAB > HBr. The adsorbed Br − can desorb simultaneously with proton adsorption, while the CTA + has adsorbed firmly on Pt(100). It has demonstrated that the irreversibly adsorbed CTA + could be mostly removed by CO adsorption/stripping. The results revealed that the origin of protecting the long-range ordered (100) structure by HBr is mainly through the inhibition of oxygen adsorption, while that by CTAB comes from both the inhibition of oxygen adsorption and the CTA + irreversible adsorption. The study has thrown insights in understanding the interaction of Br − and CTA + with Pt(100), and interpreted that using CTAB as shape-tuning agent is more favorable to yield Pt nanomaterials with long-range ordered (100) surface structure. [ABSTRACT FROM AUTHOR]

High-purity H 2 was produced by the sorption enhanced steam reforming (SESR) of acetic acid, a model compound of bio-oil obtained from the fast pyrolysis of biomass, in a fluidized bed reactor. A Pd/Ni–Co hydrotalcite-like material (HT) and dolomite were used as reforming catalyst and CO 2 sorbent, respectively. The hydrogen yield and purity were optimized by response surface methodology (RSM) and the combined effect of the reaction temperature ( T ), steam-to-carbon molar ratio in the feed (steam/C) and weight hourly space velocity (WHSV) upon the sorption enhanced steam reforming process was analyzed. T was studied between 475 and 675 °C, steam/C ratio between 1.5 and a 4.5 mol/mol and WHSV between 0.893 and 2.679 h −1 . H 2 yield, H 2 selectivity and H 2 purity, as well as the CH 4 , CO and CO 2 concentrations in the effluent gas, were assessed. The operating temperature proved to be the variable that had the greatest effect on the response variables studied, followed by the WHSV and the steam/C ratio. The results show that the H 2 yield, H 2 selectivity and H 2 purity increased, while the CH 4 , CO and CO 2 concentrations decreased, concurrently with the temperature up to around 575–625 °C. Higher values of the steam/C ratio and lower WHSV values favored the H 2 yield, H 2 selectivity and H 2 purity, and reduced the CH 4 concentration. It was found that the SESR of acetic acid at atmospheric pressure and 560 °C, with a steam/C ratio of 4.50 and a WHSV of 0.893 h –1 gave the highest H 2 yield of 92.00%, with H 2 purity of 99.53% and H 2 selectivity of 99.92%, while the CH 4 , CO and CO 2 concentrations remained low throughout (0.04%, 0.06% and 0.4%, respectively). The results also suggested that a slow CO 2 capture rate led to a poor level of hydrogen production when the SESR process was carried out at low temperatures, although this can be improved by increasing the sorbent/catalyst ratio in the fluidized bed. [ABSTRACT FROM AUTHOR]

Purpose Tilapia is an important agricultural fish that has been plagued by Group B streptococcus (GBS) infections in recent years, some of them severe. It is well-known that surface immunogenicity protein (Sip) is an effective vaccine against GBS. Experimental design Since Sip was not expressed in either E. coli BL21 or E. coli Rosetta, we removed the N-terminal signal peptide and LysM of the virus to produce purified truncated Sip (tSip 1 1 tSip: truncated Sip. ), which multiplied easily in an E. coli host. The antibody's ability to recognize and combine with GBS was determined by Western-blot and specific staining in vitro . The relative percentage of survival (RPS), antibody titers, bacterial recovery, and pathologic morphology were monitored in vivo to evaluate the immune effects. Freund's incomplete adjuvant (FIA) plus tSip and aluminum hydroxide gel (AH) plus tSip were also evaluated. Results It revealed that tSip mixed with FIA was an effective vaccine against GBS in tilapia, while AH is toxic to tilapia. [ABSTRACT FROM AUTHOR]