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First, UV stopped-flow profiles were measured upon rapid mixing a series of soluble metal salt precursors with the Na 2 CO 3 solution to detect the kinetics of the complicated process involving the insoluble material formation reaction and the subsequent nanoparticles growth. Comparing the kinetic curves in 60 ms with 300 ms at 45–65 °C, it illustrates that the formation reaction of insoluble transition metal carbonates occurs rapidly (shorter than 60 ms) and precipitates as nanoparticles that act as the seeds for the subsequent particle growth. Then, a High-Shear co-Precipitation (HSP) method was developed to synthesize uniform LiNi 0.6 Co 0.2-x Mn 0.2 La x O 2 , overcoming the inherent difference of tens of magnitude in the solubility product constant (K sp) of individual carbonates. The synthesized LiNi 0.6 Co 0.198 Mn 0.2 La 0.002 O 2 exhibits an initial discharge capacity of 200.5 mAh g−1, superior to LiNi 0.6 Co 0.2 Mn 0.2 O 2 (194.7 mAh g−1, 0.1 C). In addition, the phosphorous coating of LiNi 0.6 Co 0.198 Mn 0.2 La 0.002 O 2 increased the capacity retention up to 86.4 % (400th, 5 C). DFT calculations indicate that La-intercalation can enlarge the Li+ layer spacing and reduce the Li+ migration energy barrier. This work illustrates the importance of the pulverization effects exerted by the High-Shear force on various insoluble nanoparticles during the initial rapid mixing period, providing a useful tool for manufacturing heteroatom-intercalated bulk nickel-rich cathode material. [Display omitted] • Insoluble carbonates nanoparticles are mixed evenly by ultrafast High-Shear force. • LiNi 0.6 Co 0.2-x Mn 0.2 La x O 2 is synthesized via a High-Shear co-Precipitation method. • LiNi 0.6 Co 0.198 Mn 0.2 La 0.002 O 2 shows an initial capacity of 200.5 mAh g−1 (0.1 C). • P-coating synergically improves the retention to 86.4 % (400th, 5 C). • La-intercalation enlarges the Li+ layer spacing of nickel-rich cathode. [ABSTRACT FROM AUTHOR]

[Display omitted] • A "core-shell" model is proposed. • Soot formation mechanism is revealed. • ·OH radical inhibits and delays the growth of soot particle effectively. • Reforming reactions primarily occur in systems that contain benzene rings. • Free radicals prefer to react with benzene ring to help cleavage benzene rings. Active cooling technology serves as one of the promising and effective methods for addressing the thermal protection strategy for hypersonic aircraft. While the coke generated through pyrolysis, dehydrogenation and coking reactions of fuel will reduce the heat transfer efficiency, even clog the heat exchange channel. In this work, three-component RP-3 aviation fuel was adopted as model compounds to investigate the cracking coking reaction mechanism and explore the method of inhibiting coking. It is found that the three-component RP-3 molecules generate an intermediate system dominated by C 2 products through bond breaking, reforming and bimolecular reactions (mainly hydrogen abstraction reactions) under supercritical state, in which the ·H radicals, as represented radicals, play a crucial role in the opening of benzene rings. The coking process is analyzed in details furtherly, and detailed soot formation mechanisms are revealed. Additionally, a suitable "core-shell structure" model is proposed to describe the coke formation process. Meanwhile, it is found that the addition of a small number of addition agents can effectively inhibit the formation of coke and thus prolong the residence time of fuel molecules in the heat transfer channel for the coking process mainly consisted of addition reaction. The study attempts to provide a theoretical basis for the high-temperature pyrolytic coking mechanism of endothermic hydrocarbon fuel, as well as the significance to understanding the inhibition of coke formation. [ABSTRACT FROM AUTHOR]

The flow behavior of polydisperse particles in rolling mode rotating drum is important in industry, but it is still not clear. In this work, the discrete element method (DEM) is used to explore the flow of particles in the three-dimensional drum. After the accuracy of simulation verified by the experimental data from literature, the particle bed is divided into active layer and passive layer. The flow behavior of polydisperse particles was revealed by studying the particle velocity, residence time, mixing and axial dispersion in different regions in the drum. By exploring the parameters such as rotation speed, filling level and the shape and position of the lifter, some ideas are provided for improving the performance of the rolling mode rotating drum. In addition, the difference of flow behavior between polydisperse particles and monodisperse particles is also given, which can provide some reference for the industrial application of complex particle system. Flow behavior of polydispersed particles in active and passive layers and the parameter optimization of rotating drum. [Display omitted] • DEM is used to study the flow behavior of polydisperse particles in a rolling mode rotating drum. • Velocity, residence time, mixing and axial dispersion of active and passive layers are studied. • Improvement scheme of filling level, rotation speed and lifter of rotating drum is given. • Reference is provided for application of monodisperse particle theory to polydisperse particles. [ABSTRACT FROM AUTHOR]

Iron and iron oxides have been employed to catalyze supercritical water gasification (SCWG) of lignin, a typical component of pulp and paper mill wastewater. To investigate the effects of different oxidation sates of Fe-based catalysts during SCWG process, all simulations were carried out through ReaxFF molecular dynamics method. During the catalytic SCWG process, the degradation rate of guaiacyl dimer lignin (GDL) molecule was inversely proportional to the valence state of iron, the higher oxidation state of Fe in iron-based catalyst was, the lower the catalytic degradation ability would be, and then GDL molecule underwent a series of reactions, accompanying with the generation of small molecules, among most of them were fuel gas products. In terms of gas products, Fe catalyst had a unique advantage in catalytic hydrogen production. Moreover, it is found that iron with low oxidation state was beneficial to the formation of CO, while iron with high oxidation state was CO 2. Our simulation results further revealed the formation mechanisms of CO, CO 2 and CH 4. Migration of lattice oxygen in iron oxides was also visualized through figure, and spent catalyst showed different sources in the final, demonstrating that SCW participates in the entire reaction providing not only H but also O free radicals. [Display omitted] • The effects of Fe-based catalysts with different oxidation state were investigated. • Degradation rate of lignin was inversely to the valence state of Fe in SCWG process. • The formation mechanism of fuel gases on Fe-based catalyst was exhibited. • Zero-valence Fe catalyst had a unique advantage in catalytic hydrogen production. • The output of CO and CO 2 was related to the oxidation state of Fe. [ABSTRACT FROM AUTHOR]

Quasi-resolving subcategory, as a generalization of resolving subcategory, was introduced in Zhu (J Algebra 414:6–40, 2014). Let A be an abelian category, X a quasi-resolving subcategory of A and H an Ext-injective cogenerator for X . We study the subcategory consisting of all the objects with finite X -resolution dimension. Furthermore, we investigate the objects with approximations by objects which are either with finite H -resolution dimension or else in X . As applications, we give the finiteness criteria of the homological dimensions in Gorenstein categories of modules and complexes. [ABSTRACT FROM AUTHOR]

Development of high-performance, high-stability and low-cost electrocatalysts toward the oxygen evolution reaction (OER) is pivotal to the water electrolysis at industrial current density. Herein, a novel Fe/Ni-based hierarchical structure was constructed with the assistance of 2D MXene, showing vertically aligned Ni(OH) 2 nanosheets decorated with distinct Fe 2 O 3 morphologies. The Fe 2 O 3 /Ni(OH) 2 /NF exhibited a remarkable OER activity and required only overpotentials of 291, 319 and 341 mV respectively at 500, 1000 and 1500 mA cm−2 in alkaline solution and drove the current density of 1300 mA cm−2 about 17 h at the potential of 1.64 V vs RHE. The Fe 2 O 3 /Ni(OH) 2 precursor underwent in situ surface reconstitution into active FeOOH/NiOOH during alkaline OER. The outstanding performance of Fe 2 O 3 /Ni(OH) 2 /NF was attributable to the synergistic impact between FeOOH and NiOOH for regulating the optimal adsorption of OER intermediates. This work provides an ideal perspective to fabricate resource-rich, low-cost and high-activity FeNi-based electrode for alkaline OER at industrial current density. The Fe 2 O 3 /Ni(OH) 2 /NF array architecture decorated with distinct Fe 2 O 3 morphologies, exhibits ultralow overpotential of 341 mV at 1500 mA cm−2 for alkaline OER and outstanding long term stability. The boosted OER activity is attributable to potential-induced surface reconstruction of Fe 2 O 3 and Ni(OH) 2 into more active FeOOH and NiOOH species, respectively. [Display omitted] • The Fe 2 O 3 /Ni(OH) 2 /NF displays nanoarrays decorated with distinct Fe 2 O 3 morphologies • The Fe 2 O 3 /Ni(OH) 2 /NF only requires overpotentials of 341 mV at 1500 mA cm−2 in 1.0 M KOH • The Fe 2 O 3 /Ni(OH) 2 /NF can deliver 1360 mA cm−2 for 17 h at 1.64 V vs RHE • In situ surface reconstitution enables promoted OER activity • The synergy of FeOOH/NiOOH regulates the optimal adsorption of OER intermediates [ABSTRACT FROM AUTHOR]

Abstract: A series of non-symmetric BODIPYs containing thieno[3,2-b]pyrrole moiety were synthesized in 21–63% yields. The absorption and emission maxima covered from the visible green to red region (λ abs=532–647nm; λ em=547–664nm; Φ f=0.19–0.45). X-ray analysis indicated that the S–C bond lengths were shorter than those of thienopyrrole and thienohelicene by 0.03–0.05Å. The crystal packing pattern suggested that strong π–π interaction, intermolecular C–H⋯F interaction, and weak S⋯π interaction existed. The tunable emission was achieved by structure modifications. Oxidation of BODIPY (λ em=547nm) with m-CPBA generated thiophene-1,1-dioxide derived BODIPY (λ em=528nm). Knoevenagel-type condensation of BODIPY with N,N-dimethylaminobenzaldehyde led to BODIPY (λ em=693nm) with extended conjugation. [Copyright &y& Elsevier]

The terminal constraints in entry guidance design are generally position and velocity constraints. In this study, the terminal time constraint is also taken into account. The estimates of time-to-go and range-to-go are discussed based on the quasi-equilibrium glide condition. Further analysis reveals that only two among the time-to-go, range-to-go, and terminal velocity are independent. Based on this observation, a guidance method is designed, which provides a new aspect to exploit the potential of entry guidance. [ABSTRACT FROM AUTHOR]

A silting theorem was established by Buan and Zhou as a generalisation of the classical tilting theorem of Brenner and Butler. In this paper, we give an alternative proof of the theorem by using differential graded algebras. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molecular oxygen can be facilely activated on oxygen vacancy under electric field. • Toluene is initially activated to benzyl cation and then oxidized to benzaldehyde. • The benzaldehyde selectivity is 83.5% at the toluene conversion of 83.4%. • O 2 2- ads and O 2 - ads are dominant active species for selective oxidation of toluene. Benzaldehyde is much easier to be oxidized with respect to toluene, making the selective oxidation of toluene to benzaldehyde extremely challenging. Herein, a series of heteropoly acid catalysts with different ratios of molybdenum and vanadium supported on carbon paper (CP) were synthesized. The oxygen vacancy concentration and dispersion of heteropoly acid on CP can be changed by regulating the ratio of molybdenum and vanadium. Due to the suitable oxygen vacancy concentration and most uniform dispersion on CP, HPMoV 2 has the highest electrocatalytic oxidation performance, showing the benzaldehyde selectivity of 83.5% at the toluene conversion of 83.4%. In-situ Raman spectroscopy proved that toluene was initially activated into benzyl cation and further oxidized by active oxygen species (O 2 2- ads , O 2 - ads) to form benzaldehyde. The active oxygen species generated by electro-activation of molecular oxygen adsorbed on oxygen vacancies of heteropoly acid, mainly contribute to the selective oxidization of toluene into benzaldehyde. This work develops a new electrochemical strategy to achieve highly selective conversion of toluene into benzaldehyde with molecular oxygen under mild conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] The superior ECH performance of Pt/C/CFP for BA is achieved by the graphitization degree of carbon fiber optimizing electrons around the Pt regions, further altering the adsorption strength of BA. • Highly selective conversion of BA into CCA was achieved via ECH. • The Pt/C/CFP electrode exhibites ECH performance with 100% selectivity and conversion. • The Pt/C/CFP electrode possesses outstanding stability after 10 ECH cycles. • Carbon fiber with different defect degrees can regulate the electron density of Pt. • In situ Raman and DFT results revealed the adsorption strength of BA on Pt. Cyclohexanecarboxylic acid (CCA), an important chemical and pharmaceutical intermediate, is commonly produced from thermal catalytic hydrogenation of benzoic acid (BA) under high temperature and pressure. Herein, electrocatalytic hydrogenation (ECH) for highly selective conversion of BA into CCA using carbon fibers with different graphitization degree (carbon fiber paper (CFP), carbon fiber cloth (CFC)) supported commercial platinum carbon (Pt/C) electrode was reported for the first time without using external H 2. Our experimental results show that, at room temperature and 1 atm, the BA conversion and the CCA selectivity are both as high as 100% in 0.05 M H 2 SO 4 over carbon fiber paper (CFP)-supported Pt/C (Pt/C/CFP). Meanwhile, Pt/C/CFP electrode still maintains outstanding stability after 10 reaction cycles. In situ Raman results and theoretical calculations reveal that the adsorption strength of BA over Pt/C/carbon fibers electrode varies with the graphitization degree of carbon fibers along with the applied potential. The superior ECH performance of the Pt/C/CFP is mainly attributed to the high dispersity of Pt/C catalysts on CFP as well as unique electronic interaction, which improved the adsorption and activation of BA. Typically, CFP with few defects can induce the accumulation of electrons around the Pt regions and enhance the electron-deficient aromatic adsorption thus improving the ECH performance of Pt/C/CFP, which is the opposite for CFC with more defects. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to compare the difference of clinical efficacy between conventional intraperitoneal chemotherapy and HIPEC, so as to explore the clinical application value and advantages of HIPEC. Design: A retrospective analysis was conducted on 80 patients with malignant ascites admitted to our hospital from June 2017 to June 2019. The general clinical data and qualitative data of the treatment results of 80 patients with malignant ascites were processed by SPSS19.0 using χ2 test, and quantitative data were processed by t test. P < 0.05, statistical data can be considered statistically significant. Results: There was no significant change in vital signs and temperature in the observation group during the treatment, and the difference was not statistically significant. The short-term total effective rate of patients in the observation group was 91.11%, and the short-term total effective rate of the patients in the control group was 40%. There was no significant difference in the incidence of adverse reactions between the two groups of patients. Conclusion: Intraperitoneal hyperthermic chemotherapy combined with intravenous chemotherapy can significantly control malignant ascites and has small adverse reactions, which is worthy of clinical promotion and application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Expandable single crystal organic precursors to form carbon composites for Li battery. • Carbon nanosheets with nickel-N-doping have high performances in cycle and rate. • Microporous-mesoporous structure formed by metal and N doping enhances Li+ adsorption. • DFT is used to study the adsorption and diffusion of Li+ in the metal-N-doping carbon. Organic-based and metal-organic-based matters are used as electrode materials or precursors for lithium ion batteries because of their high chemical stability and flexible molecular adjustability. Nevertheless, the unobvious electrochemical performance and unclear structure hinder the study of the lithium ions storage mechanism of them. In this paper, we design a well-defined single-crystal structure of organic crystal precursor (CN-Ni/Mn) and derived porous carbon nanosheets with metal-nitrogen-doping (CN-Ni/Mn-800) as electrode materials to construct independent high-performance lithium ion batteries. The study shows that a large number of interconnected micropore mesoporous structures obtained by the transformation of macropores in the materials improve the lithium storage capacity. Density functional theory (DFT) calculations show that the lithium ions adsorption energy and diffusion ability of CN-Ni/Mn-800 are higher than those of N-doped carbon-based materials (CN-800). CN-Ni-800 has the best performance among the anode materials of the half battery. It can deliver stable long-term cycling performance over 1000 charge-discharge cycles at 500 mA g−1. This is a new strategy that designed precursors with a single-crystal structure to derive carbon-based materials for developing high-performance batteries. [ABSTRACT FROM AUTHOR]

The natural phenolic substance, 18β-glycyrrhetinic acid (GRA), has shown enormous potential in the chemoprevention of cancers with rich resources and biological safety, but the GRA-regulated genetic and epigenetic profiles are unclear. Deregulated mitochondrial cellular energetics supporting higher adenosine triphosphate provisions relative to the uncontrolled proliferation of cancer cells is a cancer hallmark. The Toll-like receptor 2 (TLR2) signaling pathway has emerged as a key molecular component in gastric cancer (GC) cell proliferation and epithelial homeostasis. However, whether TLR2 influenced GC cell energy metabolism and whether the inhibition effects of GRA on GC relied on TLR2 signaling were not illustrated. In the present study, TLR2 mRNA and protein expression levels were elevated in gastric tumors in the K19-Wnt1/C2mE (Gan) mice model, GC cell lines and human GCs, and the overexpression of TLR2 was correlated with the high histological grade and was a poor prognostic factor in GC patients. Further gain and loss of function showed that TLR2 activation induced GC cell proliferation and promoted reactive oxygen species (ROS) generation, Ca2+ accumulation, oxidative phosphorylation and the electron transport chain, while blocking TLR2 inhibited mitochondrial function and energy metabolism. Furthermore, GRA pretreatment inhibited TLR2-activated GC cell proliferation, energy metabolism and carcinogenesis. In addition, expression of TLR2 was found to be downregulated by GRA through methylation regulation. Collectively, the results demonstrated that GRA inhibited gastric tumorigenesis through TLR2-accelerated energy metabolism, suggesting GRA as a promising therapeutic agency targeting TLR2 signaling in GC. [ABSTRACT FROM AUTHOR]

Herein, we developed a novel and simple strategy to construct Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver large current densities in alkaline electrolyte. It is of great interest to find that the versatile role of few-layered Ti 3 C 2 endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2. It is worth noting that the interconnected array electrode exhibits noticeable hydrogen evolution reaction (HER) performance, achieving ultralow overpotentials of 107, 145 and 184 mV at high current densities of 500, 1000 and 1500 mA cm−2, respectively, which outperforms most reported HER electrocatalysts. It requires only 1.95 V to drive 1000 mA cm−2 towards full water electrolysis along with considerable stability. It is demonstrated for the first time that the synergistic effect of Pt and TiO 2 /Ni(OH) 2 the enhanced HER performance. This work reports a robust nanoarray support for Pt electrocatalyst to break through its intrinsic barrier in alkaline HER and under large current density. A novel and simple strategy was proposed to construct robust Pt-decorated TiO 2 /β-Ni(OH) 2 nanosheet arrays that steadily deliver industrial current densities at ultralow overpotentials in alkaline electrolyte. The unexpected HER activity originates from the synergy between Pt and TiO 2 /Ni(OH) 2 along with the interconnected array architecture. [Display omitted] • Pt/TiO 2 /Ni(OH) 2 /NF possesses ultralow HER overpotential at high current density. • Pt/TiO 2 /Ni(OH) 2 /NF couple requires small cell voltage for overall water splitting. • 2D MXene endows the unique growth mechanism of Pt/TiO 2 /β-Ni(OH) 2 nanosheet. • The synergy between Pt and TiO 2 /Ni(OH) 2 contributes to the enhanced HER activity. • The interconnected array architecture overcomes the mass transfer resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interaction between viscosity reducers and asphaltene were investigated. • The viscosity VR I system has relatively lower average cluster sizes of asphaltene. • The stacking modes shift during the process of viscosity reduction. • The solvent of toluene exhibits larger solvation free energy for asphaltene. • Asphaltene dimer shows weaker binding energy and shorter stacking distance in toluene. Faced with the problem of high viscosity of heavy oil, revealing interaction mechanism of viscosity reduction from molecular level is of significance for scientifically designing viscosity reducers. Therefore, molecular dynamics (MD) and quantum mechanics (QM) simulations were combined to conduct a profound research on viscosity reduction mechanism of heavy oil. Three kinds of viscosity reducers (VRs) used in experiment were modeled and inserted into the heavy oil box systems constructed for simulation. By comparing average cluster sizes of asphaltenes in each system, and interactions between the characteristic atoms in the VRs' branches and asphaltenes, the difference in the effects of different viscosity reducers were fully understood. After analyzing the π-π stacking forms among asphaltenes-asphaltenes, asphaltenes-resins, and resins-resins in different simulation systems, a potential viscosity reduction mechanism was proposed. The strong face-face stacking between asphaltenes and asphaltenes in heavy oil is converted into a relatively weaker face-face stacking of asphaltene-resin, with weak interaction type and strength among heavy oil molecules further explored. Finally, a criterion for screening solvents was put forward after investigating the property of different solvents, toluene and kerosene. Molecule simulation was carried out to reveal the mechanism for viscosity reduction of heavy oil under molecular level, which made a contribution to the exploration of heavy oil. [ABSTRACT FROM AUTHOR]

Accumulating epidemiological and clinical evidence shows that inflammation is an important risk factor for gastrointestinal diseases. Glycyrrhiza glabra, a traditional Chinese medicine, has been shown to safely suppress gastric cancer; however, the anti-inflammatory mechanisms in gastric tumorigenesis have been poorly investigated. Therefore, this study is committed to demonstrate the in vivo anti-inflammatory effect of 18β-glycyrrhetinic acid (GRA), the main active component of G. glabra. The lymphocytes and macrophages were heavily infiltrated in the transgenic mice that highly expressed cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase (mPGES)-1; however, a significant reduction was observed after treatment with GRA. In addition, GRA downregulated the protein levels of COX-2, GαS, EP2, and β-catenin, which were involved in the arachidonic acid pathway. In conclusion, our study showed the potential protective effects of GRA against inflammatory environment that might be involved in gastric tumorigenesis in vivo through the PGE2-EP2 receptor-mediated arachidonic acid pathway. [ABSTRACT FROM AUTHOR]