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In this study, the performance of 2-hydroxy-3-naphthylmethyl hydroxamic acid (NHA) in cassiterite flotation was investigated. The aim was to understand the mechanism of action of NHA for the first time. The effect of NHA as a collector in the flotation separation of cassiterite, calcite, and quartz was investigated via microbubble flotation experiments. The experimental results showed that the maximum recovery of cassiterite in the presence of NHA was 91.76%. This was attributed to the selective adsorption of NHA on the cassiterite surface. NHA showed a stronger collection performance for cassiterite than calcite and quartz. Therefore, the mechanism of NHA-cassiterite interaction was investigated using zeta potential, the logarithmic solubility plot (LSD), Fourier Transform Infrared (FT-IR), X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscope (SEM) analyses. This study introduces a new adsorption process and mechanism for the NHA-based adsorption of cassiterite. The results show that, under neutral conditions, the solute components of cassiterite surface lattice ions mainly exist in the form of Sn–OH complexes. Chemisorption occurs between cassiterite and NHA which is adsorbed onto the cassiterite surfaces through interaction with O sites, rather than Sn sites as is traditionally expected. Further, the hydroxyl and hydroxyl groups of NHA are chemically coordinated with Sn–OH on the surface of cassiterite to form a six-membered chelate ring. This proposed mechanism can be extended to most systems in which metal ions interact with hydroxamic acids bearing hydroxyl groups. This contributes to a better understanding of the activation mechanism of hydroxamic acid collectors in cassiterite flotation. [ABSTRACT FROM AUTHOR]

Synergistic drug combinations have demonstrated effective therapeutic effects in cancer treatment. Deep learning methods accelerate identification of novel drug combinations by reducing the search space. However, potential adverse drug–drug interactions (DDIs), which may increase the risks for combination therapy, cannot be detected by existing computational synergy prediction methods. We propose DEML, an ensemble-based multi-task neural network, for the simultaneous optimization of five synergy regression prediction tasks, synergy classification, and DDI classification tasks. DEML uses chemical and transcriptomics information as inputs. DEML adapts the novel hybrid ensemble layer structure to construct higher order representation using different perspectives. The task-specific fusion layer of DEML joins representations for each task using a gating mechanism. For the Loewe synergy prediction task, DEML overperforms the state-of-the-art synergy prediction method with an improvement of 7.8% and 13.2% for the root mean squared error and the R2 correlation coefficient. Owing to soft parameter sharing and ensemble learning, DEML alleviates the multi-task learning 'seesaw effect' problem and shows no performance loss on other tasks. DEML has a superior ability to predict drug pairs with high confidence and less adverse DDIs. DEML provides a promising way to guideline novel combination therapy strategies for cancer treatment. [ABSTRACT FROM AUTHOR]

Intercomponent electron transfer channels were established via various interface structures formed between amorphous Pd or crystalline Pd and In 2 O 3 , Pd A acted as electronic pump, facilitating the transfer and separation of photogenerated electrons, resulting in their subsequent enrichment on the surface of amorphous Pd. [Display omitted] • Amorphous Pd is constructed exploiting hydrogen-induced amorphization effects. • Pd-In 2 O 3 exhibited 3-fold improvement selectivity of CH 3 OH + CO as compared with In 2 O 3. • The progressive electrons transfer between reactant molecules and catalysts. • Amorphous Pd as an electron pump to optimize electron transfer. • The number of electrons received by CO 2 is the key to improving product selectivity. The progressive transfer of photogenerated electrons between the catalyst components and reactants is of great significance for photocatalysis. Amorphous Pd (Pd A) and oxygen vacancies (V O s) were simultaneously introduced in Pd-In 2 O 3 exploiting hydrogen-induced amorphization effects; 0.6 wt% Pd-In 2 O 3 exhibited a 4.5-fold increase in activity and a 3.2-fold higher selectivity toward CH 3 OH + CO (63.62 %) compared with In 2 O 3. Multiple in situ techniques and theoretical calculations revealed that intercomponent electron transfer channels were established via various interface structures formed between Pd A or crystalline Pd (Pd C) and In 2 O 3 ; Pd A acted as electronic pump, facilitating the transfer and separation of photogenerated electrons, resulting in their subsequent enrichment on the surface of Pd A. Simultaneously, Pd A acted as electron-donating adsorption site for H 2 O, increasing the number of electrons received by H 2 O, further inhibiting the competitive adsorption of H 2 O and CO 2 on V O sites, and promoting the hydrogen evolution reaction. Additionally, the electronic coupling between Pd C and V O s could significantly decrease the electron-donating ability of V O s, reducing the number of electrons received by CO 2 , thus effectively regulating the degree of CO 2 reduction. This study employs Pd A /Pd C and V O s to synergistic optimize the progressive transfer of photogenerated electrons, and presents a novel approach for elucidating the catalytic mechanism. [ABSTRACT FROM AUTHOR]

Photogenerated holes and electrons were enriched and localized at the site of Pd2+ and V O s, respectively, which caused the bidentate (HCOO BX) changing to monodentate (HCOO MX) mode under light irradiation, resulting in the enhance charge carrier separation over the p-n junction and then producing H 2. [Display omitted] • The p-type PdO/n-type TiO 2 junction was constructed successfully. • The oxidation site was observed at the site of Pd2+ via means of quasi EPR. • The activity of PdO/TiO 2 was nearly 1298 times higher than the pure TiO 2. • Adsorption activation induced by the electron transfer behavior of FA. • The FA adsorption modes was transformed from bidentate to monodentate. A prepared p-type PdO/n-type TiO 2 junction was prepared as the catalyst for photocatalytic hydrogen evolution from formic acid (FA). It was found that PdO/TiO 2 exhibited 1298-fold higher activity than TiO 2 under ultraviolet and visible light irradiation at room temperature. Multiple characterization techniques were utilized to demonstrate that doping PdO into TiO 2 can regulate the Fermi level of the sample and the adsorption behavior of FA, resulting in different electron transfer behavior between FA and PdO/TiO 2 compared to that between FA and TiO 2. Oxygen vacancies acted as electron donors to deliver photogenerated electrons from TiO 2 to the adsorbed bidentate FA, which increased the electron density on the O atom of FA and led to the formation of activated monodentate FA. This activated FA was more easily oxidized by the holes in PdO generated by visible light, leading to the production of H 2 and CO 2. The mode of adsorption associated with the Pd2+ site is the key factor in driving this reaction and leading to the reversible electron transfer phenomenon. This study provides a new promising route for the design of photocatalysts for self-decomposition reactions. [ABSTRACT FROM AUTHOR]

Public key encryption with keyword search (PEKS) allows users to search on encrypted data without leaking the keyword information from the ciphertexts. But it does not preserve keyword privacy within the trapdoors, because an adversary (e.g., untrusted server) might launch inside keyword-guessing attacks (IKGA) to guess keywords from the trapdoors. In recent years, public key authenticated encryption with keyword search (PAEKS) has become a promising primitive to counter the IKGA. However, existing PAEKS schemes focus on the concrete construction of PAEKS, making them unable to support modular construction, intuitive proof, or flexible extension. In this paper, our proposal called "StopGuess" is the first elegant framework to achieve the above-mentioned features. StopGuess provides a general solution to eliminate IKGA, and we can construct a bundle of PAEKS schemes from different cryptographic assumptions under the framework. To show its feasibility, we present two generic constructions of PAEKS and their (pairing-based and lattice-based) instantiations in a significantly simpler and more modular manner. Besides, without additional costs, we extend PAEKS to achieve anonymity which preserves the identity of users; we integrate it with symmetric encryption to support data retrieval functionality which makes it practical in resource-constrained applications. • We present StopGuess for PAEKS to give a general solution to eliminate IKGA. • We present two generic constructions of PAEKS with StopGuess to demonstrate its the superiority. • We extend PAEKS to support further properties or features without additional assumptions on the underlying modules. [ABSTRACT FROM AUTHOR]

The bidirectional electron transfers of FA adsorption was induced by the LSPR of small-sized metallic Ni, resulting in a unique "valley-shaped" gas sensitive response, which was the main factor for the activity under Vis and UV+vis radiation. [Display omitted] • A NiO/TiO 2 heterojunction loaded with 7 nm metallic Ni was constructed successfully. • The activity of Ni/TiO 2 was nearly 1271 times higher than the pure TiO 2. • The visible-light activity was much higher than ultraviolet light. • Adsorption activation induced by the electron transfer behavior of formic acid. • The LSPR effect-induced bidirectional electron transfers of formic acid adsorption. Photocatalytic hydrogen production from formic acid (FA) is a daunting challenge, yet an essential task for the development of hydrogen energy. In this study, a p-NiO/n-TiO 2 heterojunction incorporating 7-nm metallic Ni was fabricated, which demonstrated a remarkable localized surface plasmon resonance (LSPR) effect. Notably, 5 wt% Ni/TiO 2 exhibited 1271-fold higher photocatalytic activity (2416 μmol⋅g−1⋅h−1) than TiO 2 alone under light radiation at room temperature. The experimental investigations revealed the excitation of distinct components via irradiation by different light sources. Visible light-driven hydrogen production was predominantly influenced by the LSPR-induced hot electrons and holes effects of Ni. Further, FA molecules simultaneously lost and accepted electrons at the Ni0–Ti3+ and Ni0–O2− sites, respectively, generating a bidirectional electron transfer behavior with "valley-shaped" gas-sensitive responses, which was crucial to boost the activity. Moreover, the photocatalytic activity was mainly attributed to the heterojunction and defects structure under UV light irradiation, and Ti3+, V O s, and O2− as adsorption sites for FA. Thus, the synergistic interplay among different light sources could effectively boost the photocatalytic hydrogen production performance. Significantly, this research reveals that the LSPR effect of metallic Ni can effectively regulate electron transfer behavior and enhance visible light-driven photocatalytic activity. [ABSTRACT FROM AUTHOR]

Purpose: This study answer calls for research on host country nationals (HCNs) by examining factors that may influence HCN task performance and contextual performance during work with their self-initiated expatriate (SIE) colleagues. Participants and Methods: Data on personality traits (extraversion, openness), socialization self-efficacy, and frequency of interaction, task, and contextual performance were collected by surveying 373 Chinese HCNs. The first author recruited the HCNs through SIEs working and living in China. SIEs who participated in this project provided the email addresses of HCNs with whom they worked. Results: The frequency of interactions fully mediated the relationship between (a) extraversion with task and contextual performance and (b) openness with task and contextual performance. Only socialization self-efficacy moderated the mediating effects of extraversion on task performance via the frequency of interaction; it also moderated the mediating effects of openness on contextual performance via the frequency of interactions, but not in the hypothesized direction. Conclusion: This study investigated the neglected stakeholder in the expatriation process, namely, HCNs, and what factors may impact HCNs' performance during work and collaboration with their SIE colleagues. [ABSTRACT FROM AUTHOR]

[Display omitted] • A facile platform toward nanofibers containing a heterogeneous π-conjugated core with controlled length/composition/morphology is developed. • The effect and mechanism behind of initial structure of seed (co)micelles on co-self-seeding behavior has been disclosed for the first time. • Various nanofibers containing a heterogeneous π-conjugated core can be generated by co-self-seeding with varying seeds/temperature. Co-self-seeding approach of living crystallization-driven self-assembly (CDSA) enables the generation of fiber-like micelles with a π-conjugated core of tunable length/composition/ morphology with appealing photophysical and photochemical properties. However, our understanding on the co-self-seeding strategy in the preparation of fiber-like comicelles containing a heterogeneous π-conjugated core is limited owing to very rare reports associated to this recently emerging strategy. Herein, we report that polydisperse comicelles containing a heterogeneous OPE 9 /OPV 5 (OPE = oligo(p -phenylene ethynylene), OPV = oligo(p -phenylene vinylene), the subscripts indicate the exact number of repeat unit of OPE and OPV segments) core can be formed from the mixture of OPE 9 - b -P2VP 56 and OPV 5 - b -PNIPAM 47 (P2VP = poly(2-vinylpyridine), PNIPAM = poly(N -isopropylacrylamide), the subscripts denote the degree of polymerization) with different mass ratios of OPE 9 - b -P2VP 56 to OPV 5 - b -PNIPAM 47 (M OPE9 / M OPV5) by crystallization-driven co-self-assembly via heating/cooling protocol. Subsequently, by co-self-seeding from the seed comicelles obtained by the fragmentation of as-prepared polydisperse comicelles, apparent continuous (gradient) and segmented (block) fiber-like comicelles containing a heterogeneous OPE 9 /OPV 5 core of controlled length/composition/morphology can be generated with varying annealing temperature and M OPE9 / M OPV5. Co-self-seeding from pairs of separated seed micelles of OPE 9 - b -P2VP 56 and OPV 5 - b -PNIPAM 47 with different M OPE9 / M OPV5 also can give apparently continuous and segmented fiber-like comicelles containing a heterogeneous OPE 9 /OPV 5 core. These two co-self-seeding approaches have some common and different characteristics. It is found that for these samples with the M OPE9 / M OPV5 = 1/1 and 2/1, the L n of comicelles obtained from seed comicelles showed much sharper increase with the increase of temperature relative to the L n of comicelles generated from mixed seed micelles as the temperatures were above 70 °C. On the contrary, for the M OPE9 / M OPV5 = 5/1, both sets of samples showed very similar trend of dependence of L n of resulting comicelles on the annealing temperature. These results revealed that both packing modes and mass ratios (M OPE9 / M OPV5) of seed (co)micelles affected the co-self-seeding behavior. [ABSTRACT FROM AUTHOR]

Ion transport plays a crucial role in biophysical and electrochemical applications. While being modeled by the classical Poisson–Nernst–Planck (PNP) equations, many ionic features are ignored in the course-graining modeling of ionic interactions. In this work, we study ion transport by modified PNP equations including effects arising from steric interactions and the Born solvation, which both could cause strong convection. The modified NP equations are first rewritten in a gradient-flow reformulation that involves mobility and chemical potential terms. The mobility is then approximated by upwind fluxes with various flux limiters on the half-grid points, and the chemical potential terms are then implicitly approximated by central differencing. The resulting first-order in time scheme is proved to be energy dissipative unconditionally. Furthermore, the unconditional existence of positive numerical concentration is proved by making use of the singularity of the entropy term, which prevents the concentration from approaching zero. The flux with the Minmod or Osher limiter is reduced to a second-order upwind flux in the strong convective limit. Numerical tests are performed to confirm the expected order of accuracy and the properties of the developed scheme at discrete level. In addition, our numerical experiments demonstrate that the developed schemes with limiters can achieve higher accuracy than the Scharfetter-Gummel scheme and classical upwind scheme in tests with strong convection. Finally, the developed schemes are applied to numerically assess the effects of Coulombic interaction, steric interaction, and Born solvation on the rectifying transport of ions through nanopores. • Semi-implicit schemes are designed for PNP equations with steric interactions and Born solvation effects. • Upwind fluxes with flux limiters are used to approximate the mobility. • Unconditional energy dissipation and solution positivity are proved. • High accuracy is observed in large-convection tests. • Rectifying ion transport through nanopores is studied. [ABSTRACT FROM AUTHOR]

Abstract In this work, we design and analyze a conservative, positivity preserving, and free energy dissipating finite difference method for the multi-dimensional nonlocal Fokker–Planck (FP) equation. Based on a non-logarithmic Landau transformation, a central-differencing spatial discretization using harmonic-mean approximations is developed. Both forward and backward Euler discretizations in time are employed to derive an explicit scheme and a linearized semi-implicit scheme, respectively. Three desired properties that are possessed by analytical solutions: i) mass conservation, ii) free-energy dissipation, and iii) positivity, are proved to be maintained at discrete level. Remarkably, numerical analysis demonstrates that the semi-implicit time discretization ensures the property of positivity preserving unconditionally. Due to the advantages brought by the harmonic-mean approximations, an estimate on the upper bound of the condition number of the resulting coefficient matrix is further established for the semi-implicit scheme. Extensive numerical tests are performed to validate aforementioned properties numerically. [ABSTRACT FROM AUTHOR]

Mixed matrix membranes (MMMs) based on Pebax MH 1657 (Pebax) and "sea‐urchin" like hierarchical mesopore–micropore carbon nanotube nanopolyhedras (CNPs) are fabricated for CO2 separation. The membranes have an efficient improvement in CO2 permeability and CO2/CH4 selectivity with the addition of CNPs. The improved gas‐separation performance was attributed to the hierarchical mesopore–micropore structure of nanopolyhedras in CNPs and the "sea‐urchin" like structure of CNPs. First, abundant mesopores (4.8 nm) with a large pore volume and a connected porous network structure in nanopolyhedras can provide convenient gas transmission pathways to improve the CO2 permeability. Second, micropores (1.1 nm) in nanopolyhedras play a role of molecular sieves and the outstretched CNTs of the "sea‐urchin" like structure of CNPs can extend the gas‐delivery path, which will enhance the CO2/CH4 selectivity. Therefore, the CO2 permeability and CO2/CH4 selectivity are significantly enhanced. The MMMs with 8 wt% CNP show the highest CO2 permeability of 510.1 Barrer and CO2/CH4 selectivity of 56.8, the CO2 separation performance surpassed the 2008 Robeson upper bound line. The "sea‐urchin" like hierarchical pore structure in mixed matrix membranes provides a fast transport pathway for CO2 and a screening for CH4. The CO2 permeability and CO2/CH4 selectivity have an efficient improvement. [ABSTRACT FROM AUTHOR]

The high cost of large-scale cultivation of microalgae has limited their industrial application. This study investigated the potential use of mixed biogas slurry and municipal wastewater to cultivate microalgae. Pig biogas slurry as the sole nutrient supplement, was assessed for the cultivation of Chlorella zofingiensis in municipal wastewater. Batch culture of various ratios of pig biogas slurry and municipal wastewater were compared. The characteristics of algal growth and lipid production were analyzed, and the removal rates of nitrogen and phosphate were examined. Results indicate that 8% pig bio-gas slurry in municipal wastewater, had a significant effect on microalgal growth. C. zofingiensis , with 2.5 g L−1 biomass, 93% total nitrogen and 90% total phosphorus removal. Lipid content was improved by 8% compared to BG11 medium. These findings show that mixing pig biogas slurry and municipal wastewater, without additional nutrition sources, allows efficient cultivation of C. zofingiensis. This is of high research and industrial significance, allowing cultivation of C. zofingiensis in mixed waste culture solution without additional nutrition sources. [ABSTRACT FROM AUTHOR]

A series of polyaniline–titanium dioxide (PANI/TiO 2 ) nanocomposite film sensor were fabricated by an in-situ chemical oxidation polymerization of aniline at TiO 2 (anatase) surface, and were evaluated the CO gas sensitivity under UV irradiation at room temperature. Although adding PANI into TiO 2 seemed to weaken the photo-assisted conductivity of film sensor sample at N 2 atmosphere, it enhanced the photo-assisted gas sensitivity to CO. Based on the chemical characterization results of PANI/TiO 2 by FT-IR, Raman and XPS, it is proposed that the protonated N site in PANI chains (formed by TiO 2 interacting with PANI) would promote the adsorption of CO, resulting in the more electrons from CO to PANI by the typical π–conjugated structures of benzenoid and quinonoid units and then to TiO 2 by the hydrogen bonds (N⋯H⋯O) in the interface of PANI and TiO 2 . Moreover, the presence of H 2 O could enhance this photo-assisted gas sensitivity. Furthermore, the PANI/TiO 2 powder sample also exhibited a higher activity of photocatalytic oxidizing CO than the pure TiO 2 sample, indicating that the enhancement in the photo-assisted sensing response to CO would benefit the photocatalytic oxidation of CO over PANI/TiO 2 . This study not only provides a possible approach to develop a photo-assisted gas-sensitive material by introducing the structure of organic-inorganic hybrided nanocomposite, but also provides a possible method to estimate the photocatalytic activity of a semiconductor material by testing its photo-assisted sensitivity to the reactant gas. [ABSTRACT FROM AUTHOR]

The photoconductivity and the gas sensing property of TiO 2 at room temperature under ultraviolet (UV) irradiation were compared with those under visible light irradiation (≥420 nm), respectively. It was found that UV light could cause the photoconductivity of TiO 2 and its sensing response to both ethylene and oxygen, while the visible light at 420 nm could cause the photoconductivity of TiO 2 and its sensing response to oxygen but not to ethylene. This indicates that the photo-assisted gas sensing performance of TiO 2 was dependent on its light-excited behavior: The intrinsic excitation of TiO 2 induced by UV light could produce both the holes and electrons, which exhibited a respective response to ethylene and oxygen, while the extrinsic excitation of TiO 2 induced by visible light maybe only produced the free electrons but not free holes, resulting in only a response to oxygen. Furthermore, it was found that the visible-light enhanced conductivity maybe depend on the Ti–bonded hydroxyls (Ti–OH) at TiO 2 surface. With the removal of Ti–OH by increasing temperature, the visible light could not produce the photoconductivity of TiO 2 . It was proposed that Ti–OH groups act as the shallow trapped level to cause the extrinsic excitation of TiO 2 . [ABSTRACT FROM AUTHOR]

We synthesized a novel, structured lipid containing caprylic acid at its sn‐1,3 position and docosahexaenoic acid at its sn‐2 position (1,3C‐2D‐TAG) by using a two‐step enzymatic method and then investigated the relationship between the types of fatty acids in the structured lipid and their physiological functions. Furthermore, we compared the effects of similarly structured lipids on postprandial lipid metabolism and obesity protection. The results revealed that the novel structured lipid synthesized using the enzymatic method not only exhibited better physical properties than traditional oils but also had high oxidation stability and crystallization degree. In terms of physiological function, the low‐dose 1,3C‐2D‐TAG group exhibited higher cholesterol and triglyceride levels, lower kidney weight or body weight, and higher serum aspartate aminotransferase and blood urea nitrogen levels than control group, whereas the high‐dose 1,3C‐2D‐TAG group exhibited higher triglyceride levels. Moreover, the medium‐dose 1,3C‐2D‐TAG group had remarkably higher high‐density lipoprotein cholesterol levels and lower low‐density lipoprotein cholesterol levels than the high‐lipid, control, and 1,2,3C‐TAG groups; however, the cholesterol and triglyceride levels and kidney and liver functions did not differ significantly among these groups. The study results suggest that 1,3C‐2D‐TAG can not only facilitate the effective utilization of the energy supplied by medium‐chain fatty acids but also help overcome difficulties in the absorption of long‐chain polyunsaturated fatty acids. [ABSTRACT FROM AUTHOR]

Introduction: In the aftermath of the COVID-19 pandemic, innovation has become a crucial factor for the success of entrepreneurial ventures in China. However, the mechanisms underlying the promotion of innovation by entrepreneurs are not yet fully understood. Drawing on self-determination theory, this study develops a comprehensive "motivation-behaviors-performance" model to examine the relationship between entrepreneurs' felt responsibility for constructive change and ventures' innovation performance.Methods: Two waves of questionnaire surveys with a sample of 376 entrepreneurs in East China were conducted. Hierarchical regression analysis was performed to test the hypotheses.Results: The empirical findings demonstrate that entrepreneurs' felt responsibility for constructive change is a key driver of innovation performance in ventures. Furthermore, external learning, encompassing technological and market learning, serves as a mediator for the positive link between entrepreneurs' felt responsibility and innovation performance. The study also reveals that entrepreneurs' perception of shared vision moderates the relationships between entrepreneurs' felt responsibility and both technological and market learning, such that the relationships are stronger when the perception of shared vision is higher.Discussion: These results yield important contributions to the entrepreneurial psychology research and self-determination theory. The study also has managerial implications for entrepreneurs aiming to enhance ventures' innovation performance. [ABSTRACT FROM AUTHOR]

We design an arbitrary-order free energy satisfying discontinuous Galerkin (DG) method for solving time-dependent Poisson–Nernst–Planck systems. Both the semi-discrete and fully discrete DG methods are shown to satisfy the corresponding discrete free energy dissipation law for positive numerical solutions. Positivity of numerical solutions is enforced by an accuracy-preserving limiter in reference to positive cell averages. Numerical examples are presented to demonstrate the high resolution of the numerical algorithm and to illustrate the proven properties of mass conservation, free energy dissipation, as well as the preservation of steady states. [ABSTRACT FROM AUTHOR]

Lead-free Cu 2+ -modified (Ba 0.85 Ca 0.15 )(Ti 0.9 Zr 0.1 )O 3 (BCZT− x Cu 2+ ) piezoelectric ceramics was synthesized by sol-gel method. The effects of Cu 2+ additions on sintering characteristics, the phase structure, microstructure, electrical properties and complex impedance characteristic were investigated systematically. The XRD patterns exhibited a pure perovskite structure without impurity phase in all samples. SEM micrographs, temperature dependence of dielectric constant and polarization-electric field ( P-E ) hysteresis loops indicated that a small amount of Cu 2+ addition affected the properties obviously. The results revealed that the addition of Cu 2+ significantly improved the sinterability of BCZT ceramics which resulted in a reduction of sintering temperature from 1440 °C to 1230 °C. The TG-DSC was analyzed to verify the reaction process of BCZT−Cu 2+ materials. (Ba 0.85 Ca 0.15 )(Ti 0.9 Zr 0.1 )O 3 ceramics with x=0.020 Cu 2+ exhibited good electrical properties: ε m =12,112, T c =360 K, ε r =2614, tan δ =0.026, K p =0.47 and d 33 =382 pC/N. The results indicated that Cu 2+ -modified BCZT ceramics could be a promising candidate for commercial purposes. [ABSTRACT FROM AUTHOR]

In this article, we employ the variational Bayesian method to study the parameter estimation problems of linear regression model, wherein some regressors are of Gaussian distribution with nonzero prior means. We obtain an analytical expression of the posterior parameter distribution, and then propose an iterative algorithm for the model. Simulations are carried out to test the performance of the proposed algorithm, and the simulation results confirm both the effectiveness and the reliability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper describes the beam commissioning progress of the 7 MeV H − linac injector for the proton synchrotron of Xi'an 200 MeV Proton Application Facility (XiPAF). To fulfill a flux of 105 ∼ 108p/cm2/s with a uniformity better than 90% on a 3 cm × 3 cm sample size at the experimental station, the number of the accumulated protons in each cycle in the synchrotron is designed to be larger than 2 × 1011. The protons are acquired from the H − beam stripped by the carbon foil, which enables transverse space painting during injection. The maximum pulse length of the injected beam is 40 μ s. With an estimation of 40 for the intensity gain factor, the injected beam is required to have a peak current of higher than 1 mA, with the normalized transverse emittance of 90% particles less than 6 and 4 π mm mrad for the horizontal and vertical planes, respectively, and the momentum spread of 90% particles within ± 0.45%. The injector mainly consists of an H − ion source, a low energy beam transport line (LEBT), a 3 MeV radio frequency quadrupole (RFQ) accelerator, a 7 MeV interdigital H-mode drift tube linac (IH-DTL), and an injection beam transport line. After several stages of beam commissioning, the linac injector has reached a pulsed peak current of 2.5 mA, with normalized emittance (90% particles) less than 4.4 and 2.2 π mm mrad, 90% momentum spread less than ± 0.55%, which lays a good foundation for the beam commissioning of the synchrotron. [ABSTRACT FROM AUTHOR]

Photothermal synergistic and Ni modification dramatically changed the electron transfer behavior of CO 2 (ads) and H 2 (ads) via regulating Fermi level. [Display omitted] • Photothermal synergistic changed the electron transfer behavior of CO 2 adsorption. • Photothermal synergistic and NiO X cause the formation of Ni0 and Vos-Nb sites.. • Ni modification changed the electron transfer behavior of H 2 adsorption. • CO 2 molecules may form dimer CO 2 · CO 2 δ− species on Vos-Nb sites. • CO 2 hydrogenation is affected by electron transfer behavior of CO 2 /H 2 adsorption. Thermo-driven photocatalytic CO 2 hydrogenation is studied for NiO x /Nb 2 O 5 from the point of CO 2 and H 2 adsorption behavior. Photothermal synergistic and Ni modification dramatically changed the electron transfer behavior of CO 2 adsorption (CO 2 (ads)) and H 2 (ads) via regulating Fermi level and providing Ni0 and V O s adsorption sites, respectively. The H 2 (ads) at Ni0 site donates electrons to NiO x /Nb 2 O 5 (pre-oxidized) and CO 2 (ads) at V O s-Nb5+ or Ni0 site accepts electrons from NiO x /Nb 2 O 5 (pre-reduced), while NiO x /Nb 2 O 5 displayed excellent photocatalytic activities. Furthermore, in situ DRIFTS results suggested that CO 2 (ads) will form two reaction pathways: (1) CO 2 (ads) at Ni0 site directly hydrogenated with H atoms (H 2 molecule dissociates at Ni0 to form two H-atoms) to generate CH 4 and C 2 H 6 through COOH intermediate; (2) CO 2 (ads) form dimer CO 2 · CO 2 δ− species at V O s-Nb5+ site, and it will be further disproportioned to produce CO and CO 3 δ− species, then CO 3 δ− species are gradually hydrogenated to form CH 4 and C 2 H 6. Moreover, increasing the number of CO 2 /H 2 molecules accepts/donates electrons will also improve the reduction degree of CO 2. This work offers a new explanation for photothermal synergistic. [ABSTRACT FROM AUTHOR]

Alkaline flocculation could be an attractive microalgae harvesting method, because it is low-cost, low energy consumption, and non-toxic to microalgal cells, and the high pH effectively sterilizes the microalgal biomass as well as the process water. In this paper, the mechanism of alkaline flocculation process and the difference between the two strains marine diatom Chaetoceros muelleri #862 and freshwater algae Scenedesmus quadricauda #507 were analyzed. The particle size of C. muelleri #862 cells increased linearly with the increasing pH value which increased dramatically by nearly fivefolds after alkaline flocculation. When pH was below 10.5, the absolute value of zeta potential on the surface of C. muelleri #862 increased rapidly, and also the conductivity of the solution declined quickly. The alkaline flocculation of C. muelleri #862 was mainly attributed to the production of Mg(OH) rather than calcium phosphate or calcium hydroxide. For the strain S. quadricauda #507, the cells still existed integrally as normal cells after alkaline flocculation. Firstly, with the increasing of pH in the solution, the absolute value of zeta potential had not declined. When pH was around 10.8, the absolute value of zeta potential had declined abruptly and the solution conductivity was increasing all the time. The cell wall of S. quadricauda #507 with the high content of cellulose Iα and low crystallization degree was good for the next step of saccharification or oil extraction. [ABSTRACT FROM AUTHOR]

Based on global sourcing circumstances, 166 transnational enterprises are proceeded questionnaire survey for the effects of supply chain relationship capital on cooperation performance, and Hierarchical Regression Analysis is applied to analyze the empirical research. The research reveals the stronger tie strength, network centrality, degree of confidence, and information sharing between enterprises and suppliers, the higher cooperation performance to create win-win for both buyer enterprises and suppliers and reinforce the international competitiveness of enterprises. [ABSTRACT FROM AUTHOR]

Fertilizers are major raw materials for microalgae cultivation. This study aims to reduce the cost of fertilizers and to enhance economic viability. The focus is on urea, potassium dihydrogen phosphate, and heptahydrate magnesium sulfate, which provide the main elements for algae cultivation. A central composite design was applied to optimize the medium forChlorella zofingiensiscultivation, which was considered to be a potential feedstock for biodiesel production. The optimal concentrations were 533.31 mg L–1urea, 69.50 mg L–1potassium dihydrogen phosphate, and 69.10 mg L–1heptahydrate magnesium sulfate, and the corresponding biomass concentration ofC. zofingiensiswas 2.50 g L–1after a 3-day culture. [ABSTRACT FROM PUBLISHER]

Microalgae have been considered as the most promising sources of alternative bioenergy. For the purpose of saving costs, the present work focused on the potential use of microalgae in the meliorative municipal wastewater, which contains 90% municipal wastewater and 10% dairy wash wastewater. Four microalgal species,Palmellococcus miniatus, Neochloris oleoabundans, Scenedesmus quadricanda#507, andChlorella zofingiensis, were cultured in pure municipal wastewater and meliorative municipal wastewater, respectively, for 5 days. Their biomass accumulation and removal rates of nitrogen and phosphate were measured. Results showed that the growth rates ofNeochloris oleoabundans, Palmellococcus miniatus, andChlorella zofingiensisin meliorative municipal wastewater (>0.8 g·L–1·d–1) were significantly higher than that in municipal wastewater (2.6 g·L–1·d–1), while there was no significant difference between the growth rates ofScenedesmus quadricanda#507 in meliorative municipal wastewater and in municipal wastewater.Neochloris oleoabundansexhibited the highest growth rate (0.86 g·L–1·d–1) and relatively high nutrient removal capacity.Scenedesmus quadricanda#507 had the highest P removal rate of over 94%. The four species have a similar N removal rate at about 90%. The results showed that the highest average removal rate of N and P were about 23.1 mg·L–1·d–1and 7.1 mg·L–1·d–1. Furthermore, the content of lipid or carbohydrates increased and a different profile of fatty acids were found compared to those in municipal wastewater. Cellular components changes of microalgae in meliorative municipal wastewater were favorable as raw materials for bioethanol and biodiesel production. Cultivation with meliorative municipal wastewater is a win-win culture mode that facilitates the biomass production, lipid and carbohydrate accumulation, and wastewater purification. [ABSTRACT FROM PUBLISHER]

The biomass productivity and nutrient removal capacity of simultaneous Chlorella sp. cultivation for biodiesel production and nutrient removal in raw dairy wastewater (RDW) in indoor bench-scale and outdoor pilot-scale photobioreactors were compared. Results from the current work show that maximum biomass productivity in indoor bench-scale cultures can reach 260 mg L −1 day −1 , compared to that of 110 mg L −1 day −1 in outdoor pilot-scale cultures. Maximum chemical oxygen demand (COD), total nitrogen (TN), and total phosphorous (TP) removal rate obtained in indoor conditions was 88.38, 38.34, and 2.03 mg L −1 day −1 , respectively, this compared to 41.31, 6.58, and 2.74 mg L −1 day −1 , respectively, for outdoor conditions. Finally, dominant fatty acids determined to be C16/C18 in outdoor pilot-scale cultures indicated great potential for scale up of Chlorella sp. cultivation in RDW for high quality biodiesel production coupling with RDW treatment. [ABSTRACT FROM AUTHOR]

In this work, neutral lipids (NLs) extraction capacity and selectivity of six solvents were firstly compared. In addition, an eco-friendly solvent combination of ethyl acetate and ethanol (EA/E) was proposed and tested for lipid extraction from Chlorella sp. cultivated in outdoor raceway ponds and effect of extraction variables on lipid yield were intensively studied. Results indicated that lipid extraction yield was increased with solvent to biomass ratio but did not vary significantly when the value exceeded 20:1. Lipid yield was found to be strongly dependent on extraction temperature and time. Finally, fatty acid profiles of lipid were determined and results indicated that the major components were octadecanoic acid, palmitic acid, linoleic acid and linolenic acid, demonstrating that the lipid extracted from the Chlorella sp. cultivated in outdoor raceway ponds by EA/E was suitable feedstock for biodiesel production. [ABSTRACT FROM AUTHOR]

A low sintering temperature is achieved for (Ba 0.85 Ca 0.15 )(Ti 0.90 Zr 0.10 )O 3 (BCZT) piezoelectric ceramics using Ba(Cu 0.5 W 0.5 )O 3 (BCW) as a sintering aid. The effects of the BCW content on the density, phase structure, electrical and mechanical properties are investigated. The addition of BCW content significantly improves the sinterability of the BCZT ceramics, which results in a reduction of the sintering temperature from 1450 °C to 1220 °C and an improvement in both the piezoelectric and mechanical properties. The BCZT ceramics with x = 0.8 wt.% BCW sintered at 1220 °C exhibits outstanding piezoelectric, dielectric and mechanical properties: d 33 = 541 pC/N, k p = 49%, Q m = 107, ϵ r = 5405, tan δ = 0.014 and T c = 78 °C. The ceramics also exhibit higher hardness (78 MPa) and higher fracture toughness (4.7 MPa m 1/2 ). These results indicate that the BCZT–BCW lead-free ceramics sintered at low temperatures are promising for high temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]

• Novel DG schemes are introduced for the time-dependent system of PNP equations. • The schemes are third order, positivity–preserving, and steady-state-capturing. • Experiments on both one and two dimensional benchmark examples are presented. In this paper, we design and analyze third order positivity-preserving discontinuous Galerkin (DG) schemes for solving the time-dependent system of Poisson–Nernst–Planck (PNP) equations, which have found much use in diverse applications. Our DG method with Euler forward time discretization is shown to preserve the positivity of cell averages at all time steps. The positivity of numerical solutions is then restored by a scaling limiter in reference to positive weighted cell averages. The method is also shown to preserve steady states. Numerical examples are presented to demonstrate the third order accuracy and illustrate the positivity-preserving property in both one and two dimensions. [ABSTRACT FROM AUTHOR]

Abstract: In this work we design and analyze a free energy satisfying finite difference method for solving Poisson–Nernst–Planck equations in a bounded domain. The algorithm is of second order in space, with numerical solutions satisfying all three desired properties: i) mass conservation, ii) positivity preserving, and iii) free energy satisfying in the sense that these schemes satisfy a discrete free energy dissipation inequality. These ensure that the computed solution is a probability density, and the schemes are energy stable and preserve the equilibrium solutions. Both one- and two-dimensional numerical results are provided to demonstrate the good qualities of the algorithm, as well as effects of relative size of the data given. [Copyright &y& Elsevier]

Abstract: An integrated approach, which combined freshwater microalgae Chlorella zofingiensis cultivation with piggery wastewater treatment, was investigated in the present study. The characteristics of algal growth, lipid and biodiesel production, and nutrient removal were examined by using tubular bubble column photobioreactors to cultivate C. zofingiensis in piggery wastewater with six different concentrations. Pollutants in piggery wastewater were efficiently removed among all the treatments. The specific growth rate and biomass productivity were different among all the cultures. As the initial nutrient concentration increased, the lipid content of C. zofingiensis decreased. The differences in lipid and biodiesel productivity of C. zofingiensis among all the treatments mainly resulted from the differences in biomass productivity. It is worthy of note that the diluted piggery wastewater with 1900 mg L−1 COD provided an optimal nutrient concentration for C. zofingiensis cultivation, where the advantageous nutrient removal and the highest productivities of biomass, lipid and biodiesel were presented. [Copyright &y& Elsevier]

We consider the generalized Benjamin-Ono (gBO) equation on the real line, u t + ∂ x (− H u x + 1 m u m) = 0 , x ∈ R , m = 2 , 3 , 4 , 5 , and perform numerical study of its solutions. We first compute the ground state solution to − Q − H Q ′ + 1 m Q m = 0 via Petviashvili's iteration method. We then investigate the behavior of solutions in the Benjamin-Ono (m = 2) equation for initial data with different decay rates and show decoupling of the solution into a soliton and radiation, thus, providing confirmation to the soliton resolution conjecture in that equation. In the mBO equation (m = 3), which is L 2 -critical, we investigate solutions close to the ground state mass, and, in particular, we observe the formation of stable blow-up above it. Finally, we focus on the L 2 -supercritical gBO equation with m = 4 , 5. In that case we investigate the global vs finite time existence of solutions, and give numerical confirmation for the dichotomy conjecture, in particular, exhibiting blow-up phenomena in the supercritical setting. • Computation of the ground state for different powers in the generalized Benjamin-Ono equation. • Decoupling of solution with various decay rates into solitons and radiation in BO equation. • Stable blow-up in the modified Benjamin-Ono equation and ground state mass threshold. • Blow-up vs global existence dichotomy in supercritical generalized Benjamin-Ono equation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Using NaClO was an effective way to pretreat wastewater for algae growth. [•] C. zofingiensis was able to adapt and grow well outdoors. [•] 1.314gL–1 day–1 of biomass was achieved stably under semi-continuous operation. [•] It is greatly possible to amplify C. zofingiensis production using piggery wastewater. [ABSTRACT FROM AUTHOR]

Abstract: Cultivation of Chlorella zofingiensis and nutrients removal in dairy wastewater were investigated in bench-scale outdoor ponds in winter, South China. The impacts of the two types of pH regulations, 5∼6% CO2 and acetic acid (HAc) on this process were studied. After 6days cultivation, the removal rates of total nitrogen (TN) and orthophosphate () using CO2 regulation were better than those using HAc. The removal rates of and TN were 97.5% and 51.7%, respectively using CO2 regulation; 79.6% (TN) and 42.0% () were obtained using HAc regulation. Higher biomass, protein, sugar content, and stable pH control were found using CO2 regulation. However, significantly higher lipid content (31.8%) was observed using HAc regulation. The dominant differences of fatty acids were the content of C18:1 and C18:3. The growth characteristics and environmental conditions especially during the typical logarithmic phase were also analyzed. [Copyright &y& Elsevier]

Abstract: Gas-particle and other dispersed-phase flows can be described by a kinetic equation containing terms for spatial transport, acceleration, and particle processes (such as evaporation or collisions). However, computing the dispersed velocity is a challenging task due to the large number of independent variables. A level set approach for computing dilute non-collisional fluid-particle flows is presented. We will consider the sprays governed by the Williams kinetic equation subject to initial distributions away from equilibrium of the form . The dispersed velocity is described as the zero level set of a smooth function, which satisfies a transport equation. This together with the density weight recovers the particle distribution at any time. Moments of any desired order can be evaluated by a quadrature formula involving the level set function and the density weight. It is shown that the method can successfully handle highly non-equilibrium flows (e.g. impinging particle jets, jet crossing, particle rebound off walls, finite Stokes number flows). [ABSTRACT FROM AUTHOR]

Abstract: A novel Bloch band based level set method is proposed for computing the semiclassical limit of Schrödinger equations in periodic media. For the underlying equation, subject to a highly oscillatory initial data, a hybrid of the WKB approximation and homogenization leads to the Bloch eigenvalue problem and an associated Hamilton–Jacobi system for the phase in each Bloch band, with the Bloch eigenvalue be part of the Hamiltonian. We formulate a level set description to capture multi-valued solutions to the band WKB system, and then evaluate total homogenized density over a sample set of bands. A superposition of band densities is established over all bands and solution branches when away from caustic points. The numerical approach splits the solution process into several parts: (i) initialize the level set function from the band decomposition of the initial data; (ii) solve the Bloch eigenvalue problem to compute Bloch waves; (iii) evolve the band level set equation to compute multi-valued velocity and density on each Bloch band; (iv) evaluate the total position density over a sample set of bands using Bloch waves and band densities obtained in steps (ii) and (iii), respectively. Numerical examples with different number of bands are shown to demonstrate the capacity of the method. [Copyright &y& Elsevier]

Abstract: We present a field-space-based level set method for computing multi-valued solutions to one-dimensional Euler–Poisson equations. The system of these equations has many applications, and in particular arises in semiclassical approximations of the Schrödinger–Poisson equation. The proposed approach involves an implicit Eulerian formulation in an augmented space – called field space, which incorporates both velocity and electric fields into the configuration. Both velocity and electric fields are captured through common zeros of two level set functions, which are governed by a field transport equation. Simultaneously we obtain a weighted density f by solving again the field transport equation but with initial density as starting data. The averaged density is then resolved by the integration of the obtained f against the Dirac delta-function of two level set functions in the field space. Moreover, we prove that such obtained averaged density is simply a linear superposition of all multi-valued densities; and the averaged field quantities are weighted superposition of corresponding multi-valued ones. Computational results are presented and compared with some exact solutions which demonstrate the effectiveness of the proposed method. [Copyright &y& Elsevier]

Abstract: We develop a level set method for the computation of multi-valued velocity and electric fields of one-dimensional Euler–Poisson equations. The system of these equations arises in the semiclassical approximation of Schrödinger–Poisson equations and semiconductor modeling. This method uses an implicit Eulerian formulation in an extended space—called field space, which incorporates both velocity and electric fields into the configuration space. Multi-valued velocity and electric fields are captured through common zeros of two level set functions, which solve a linear homogeneous transport equation in the field space. Numerical examples are presented to validate the proposed level set method. [Copyright &y& Elsevier]

Responses of beam position monitors (BPMs) in low-energy beamlines are sensitive to beam velocity and bunching frequency due to non-relativistic effects. However, traditional BPM calibration methods based on the coaxial wire or wire antenna can only simulate electromagnetic fields of high-energy beams with β close to 1. A helix with an inner conductor was adopted to simulate low- β beams. The dispersion relation and characteristic impedance of the helix are analyzed based on the sheath-helix model. The phase velocity and characteristic impedance of the helix have a low dependency on the frequency and helix position inside a BPM, which is crucial for calibrating low- β BPMs. A helix with a phase velocity of 0.12 c and characteristic impedance of 50 Ω is designed to calibrate the button BPMs at the Xi'an Proton Application Facility. Responses of the BPMs to the helix and a beam with β = 0.12 are simulated with CST Studio Suite. The maximum relative calibration error of the helix compared to the beam is 0.47 mm in the transverse positions within three-quarters of the BPM aperture, which shows the remarkable capability of the helix to calibrate low- β BPMs offline. [ABSTRACT FROM AUTHOR]

Having a comprehensive knowledge of phase equilibrium is advantageous for industrial simulation and design of chemical processes. For further acquisition of primary data to facilitate the separation and purification of waste oil biodiesel systems, a liquid–liquid equilibrium (LLE) tank is deployed for the ternary system of waste oil biodiesel + methanol + glycerin, thereby enhancing the precision and efficiency of the process. The phase equilibrium system was constructed under the influence of atmospheric pressure at precise temperatures of 303.15 K, 313.15 K, and 323.15 K. The equilibrium components of each substance were analyzed by employing high-temperature gas chromatography, a sophisticated analytical method that enables the identification and quantification of individual components of a sample. Moreover, the ternary liquid–liquid equilibrium data were correlated by implementing the NRTL and UNIQUAC activity coefficient models. Subsequently, the binary interaction parameters of the ternary system were derived by conducting regression analysis. The experimental data demonstrated that the presence of lower methanol content in the system resulted in nearly immiscible biodiesel and glycerol phases, which ultimately facilitated the separation of biodiesel and glycerol. Conversely, with the increase in methanol content, the mutual solubility of biodiesel and glycerol was observed to increase gradually. The results showed that the calculated values of the NRTL and UNIQUAC models aligned well with the experimental values. The root-mean-square deviations of the NRTL and UNIQUAC models at 313.15 K were 2.76% and 3.56%, respectively. [ABSTRACT FROM AUTHOR]

• The adsorption behavior of H 2 and CO is similar on the surface of TiO 2. • The lattice oxygen can be activated via H 2 and CO adsorption on the anatase surface. • CO oxidation reaction will undergo two pathways. • Lattice oxygen is activated and participates in the reaction as primary pathway. • H 2 adsorption will inhibit the primary pathway and promote the secondary pathway. In this study, the reaction mechanisms of photodriven CO oxidation over both anatase and rutile TiO 2 have been investigated from the hydrogen adsorption behavior. It can be beneficial when H 2 is introduced into CO oxidation system to increase the catalytic activity of rutile, while to decrease the catalytic activity of anatase. Further analysis revealed that H 2 molecule is dissociated on anatase surface, and then produce oxygen vacancies by dehydroxylation under UV irradiation. In contrast, the adsorbed H 2 (H 2 (ads)) with a non-dissociative mode does not activate the lattice oxygen (O lat) over rutile. For anatase, CO oxidation reaction mainly undergoes the O lat activation process, while H 2 (ads) can inhibit the O lat activation, resulting in a suppressed CO oxidation. For rutile, the surface hydroxyls are the active species for CO oxidation, while H 2 (ads) can promote to form more surface hydroxyl species, resulting in a promoted CO oxidation. [ABSTRACT FROM AUTHOR]

• Structure-preserving finite difference schemes are proposed for PNP equations. • A novel Newton's method is developed for the nonlinear system after discretization. • Numerical analysis rigorously proves desired physical properties. • The solvability/stability of a linearized problem in the Newton's method are established. Ion transport, often described by the Poisson–Nernst–Planck (PNP) equations, is ubiquitous in electrochemical devices and many biological processes of significance. In this work, we develop conservative, positivity-preserving, energy dissipating, and implicit finite difference schemes for solving the multi-dimensional PNP equations. A central-differencing discretization based on harmonic-mean approximations is employed for the Nernst–Planck (NP) equations. The backward Euler discretization in time is employed to derive a fully implicit nonlinear system, which is efficiently solved by a newly proposed Newton's method. The improved computational efficiency of the Newton's method originates from the usage of the electrostatic potential as the iteration variable, rather than the unknowns of the nonlinear system that involves both the potential and concentration of multiple ionic species. Numerical analysis proves that the numerical schemes respect three desired analytical properties (conservation, positivity preserving, and energy dissipation) fully discretely. Based on advantages brought by the harmonic-mean approximations, we are able to establish estimate on the upper bound of condition numbers of coefficient matrices in linear systems that are solved iteratively. The solvability and stability of the linearized problem in the Newton's method are rigorously established as well. Numerical tests are performed to confirm the anticipated numerical accuracy, computational efficiency, and structure-preserving properties of the developed schemes. Adaptive time stepping is implemented for further efficiency improvement. Finally, the proposed numerical approaches are applied to characterize ion transport subject to a sinusoidal applied potential. [ABSTRACT FROM AUTHOR]

The CO (ad) at WO 3 sample could donate electrons to WO 3 surface, and it could be light-driven oxidized into CO 2 by O 2 ; the CO (ad) at CuWO 4 /WO 3 could not only accept electrons, but also donate electrons to CuWO 4 /WO 3 surface, and correspondingly it could be converted into both CH 4 by H 2 and CO 2 by O 2 under light. • CO photocatalytic oxidation or reduction is somewhat dependent on its electron transfer behavior over WO 3 and CuWO 4 /WO 3. • The CO (b) donate electrons to W5+ over WO 3 , which is prone to be oxidized into CO 2. • The CO (l) and CO (gdc) accept electrons from W0 over CuWO 4 /WO 3 , which is prone to be reduced into CH 4. • The boundary adsorption theory can be deeply explained by the chemisorption mode of gas molecule. Visible-light-driven CO conversion has attracted many research efforts. Herein we study the reaction mechanism from the perspective of electron transfer behavior during CO adsorption (CO (ad)). The WO 3 and CuWO 4 /WO 3 films were in-situ synthesized, and then were investigated their behaviors for adsorbing CO and catalyzing CO conversion under visible light via gas sensing system and in-situ DRIFTS testing, respectively. It was found that the CO (ad) at W5+-W5+ site will form bridge adsorbed CO species over WO 3 , and donate electrons to W5+, resulting in its light-driven oxidation by O 2. The CO (ad) at W0 site forms linear and gem-dicarbonyl adsorbed CO species over CuWO 4 /WO 3 , and accept electrons from W0, then its reduction by H 2. The result shows the light-driven CO oxidation or reduction on WO 3 and CuWO 4 /WO 3 would be somewhat dependent on the electron transfer behavior induced by different modes of CO chemisorption and the Fermi level of sample itself. [ABSTRACT FROM AUTHOR]

To study ion transport in electrolyte solutions, we propose numerical methods for a modified Poisson–Nernst–Planck model with ionic steric effects (SPNP). Positivity preserving schemes based on harmonic-mean approximations are proposed on a nonuniform mesh for the spatial discretization of the SPNP equations. Both explicit and semi-implicit discretization are considered in time. Numerical analysis shows that explicit forward Euler and semi-implicit trapezoidal discretization lead to schemes that maintain fully discrete solution positivity under a constraint on a mesh ratio, while the semi-implicit backward Euler discretization maintain fully discrete solution positivity unconditionally. We further study the condition numbers of the matrix associated with the semi-implicit backward Euler discretization, and establish an upper bound on condition numbers, indicating that the developed discretization based on harmonic-mean approximations effectively solves the issue of the presence of large condition numbers when using the Slotboom-type variables. Further numerical simulations confirm the analysis results on accuracy, positivity, and bounded condition numbers. The proposed schemes are also applied to study practical applications, such as the impact of self and cross steric interactions on ion distribution and rectifying behavior in a slit-shaped nanopore with surface charges. Possible extensions of the numerical methods to other modified PNP models with ion correlations and steric effects are also discussed. [ABSTRACT FROM AUTHOR]

Background: Re-irradiation (re-RT) has the active effect of relieving clinical symptoms and prolonging the survival of patients with recurrent esophageal squamous cell carcinoma (ESCC). However, the optimal re-RT dose is still uncertain. Here, we analyzed the prognostic factors associated with survival and explored the optimal re-RT dose for patients with recurrent ESCC following definitive radiotherapy.Patients and Methods: The data of 47 patients with recurrent ESCC who were retreated between 2010 and 2014 were retrospectively analyzed. All patients received a radiation dose > 50 Gy during the primary treatment. The median time to recurrence after primary radiotherapy was 26 months (range 6-120 months). All patients had in-field recurrence in the esophagus. Recurrence within the local site was observed in 37 patients (78.7%), and recurrence in both the local site and regional nodes were observed in 10 patients (21.3%). All patients received 3D conformal re-RT with a median dose of 58 Gy (range 26-64 Gy). Chemotherapy was sequentially used in 27.7% of the patients. Survival curves were constructed according to the Kaplan-Meier method and were compared by log-rank tests. The factors predictive of survival were identified with univariate and multivariate analyses.Results: Dysphagia relief after re-RT was achieved in 20 of the 35 symptomatic patients (57.1%). The median survival time (MST) of all patients was 17 months, and the 1-, 2-, 3- and 5-year overall survival (OS) rates were 72.3, 25.5, 17.0 and 2.1%, respectively. In the univariate analysis, an Eastern Cooperative Oncology Group Performance Status (ECOG-PS) of 0-1 (P = 0.014), recurrence at the local site (P = 0.048), time to recurrence ≥24 months (P = 0.006) and re-RT dose ≥50 Gy (P < 0.001) were associated with favorable OS. In the multivariate analysis, only re-RT dose was an independent factor for OS (P = 0.007). Severe complications were observed in 7 patients, two of whom received a re-RT dose > 60 Gy.Conclusion: Our results demonstrated that patients with recurrent ESCC following definitive radiotherapy had unfavorable OS. Re-RT could be considered a feasible and effective treatment modality. A re-RT dose > 50 Gy could improve the survival outcomes, and a dose > 60 Gy should be administered with caution due to the risk of severe complications. [ABSTRACT FROM AUTHOR]

Knowledge of 4D beam phase space is essential to characterize beam motion along a beamline which includes elements that couple the transverse planes. A 4D phase space measurement method using multiple 2D profiles is proposed in this paper. The effectiveness of the method is validated by numerical simulations. Finally, we present a successful application of the method at the Xi'an Proton Application Facility to measure the coupled 4D phase space after a skew quadrupole. [ABSTRACT FROM AUTHOR]

For the deficiencies that the existing calculation theory for the Plastic Zone of Tunnel Surrounding Rock (PZTSR) does not consider the effect of the intermediate principal stress σ2 and interaction between the surrounding rock and support structure on the PZTSR under unequal stress, the Unified Strength Theory (UST) for the rock is adopted to replace the often used Mohr-Coulomb (M-C) strength criterion to consider the effect of σ2 on the PZTSR. Meanwhile, the interaction mechanism between the surrounding rock and support structure is also considered in the proposed model. Finally, the effect of the initial elastic displacement of the surrounding rock, stiffness of the support structure, and the coefficient b of the intermediate principal stress on the plastic zone is discussed. The results show that the PZTSR will increase nonlinearly with increasing the initial elastic displacement of the surrounding rock, and when it increases to a certain value, its increase extent will be much obvious. With increasing the stiffness of the support structure, the PZTSR will gradually decrease nonlinearly, but the decrease extent is not very much. With increasing b, the PZTSR will decrease; namely, σ2 can improve the stress condition of the surrounding rock and reduce the PZTSR. [ABSTRACT FROM AUTHOR]

Observational monitoring of employees is becoming increasingly common in startup ventures in China, creating new problems regarding employee psychology—in particular, the diminishing of employee entrepreneurial passion. We conducted a survey with 303 employees of startups in China and found that observational monitoring was negatively associated with the employees' entrepreneurial passion for inventing because it eroded employee trust in management. However, when the employees perceived a high level of psychological safety, the negative effects of observational monitoring were mitigated. Theoretical and practical implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

The experiments of the 0.18-μm pinned photodiode (PPD) CMOS image sensors (CISs) irradiated by energetic proton radiation with energies of 20, 40, 60, and 100 MeV are presented. The degradations of the mean dark signal, dark signal non-uniformity (DSNU), and fixed pattern noise (FPN) induced by protons are presented. The experimental results show that the mean dark signal degradations of the CISs decrease with increasing proton energy at the same fluence. The degradations induced by proton radiation at different fluence are also presented. The mean dark signals increase with increasing integration time at the same proton fluence. The degradation mechanisms of the CISs induced by energetic protons are analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] The roles of oxygen vacancies to enhance the electrochemical performance were not clearly explained in comprehensive research. Herein, the vertically oriented NiCo 2 S 4 /MnO 2 core–shell nanocomposites are in situ grown on the nickel foam (NF) surface and activated by oxygen vacancy engineering via a chemical reduction method. The scanning electron microscope (SEM) and transmission electron microscope (TEM) results show the shell-MnO 2 is well coated on the core-NiCo 2 S 4. The hierarchical core–shell nanostructures synergistically increase conductivity and provide rich faradaic redox chemical reactions. Moreover, the density functional theory (DFT) calculations further indicate that the electronic properties and structure properties in NiCo 2 S 4 /MnO 2 electrode of reduction for 60 min (NiCo 2 S 4 /MnO 2 -60) are effectively adjusted by introducing oxygen vacancies. Impressively, the NiCo 2 S 4 /MnO 2 -60 electrode delivers substantially appreciable areal capacity of 2.13 mAh·cm−2 couple with superior rate capability. The as-prepared high-performance electrode material can assemble into solid-state hybrid supercapacitor. The fabricated NiCo 2 S 4 /MnO 2 -60//AC device exhibits an exceptional energy density of 43.16 Wh·kg−1 at a power density of 384.21 W·kg−1 and satisfactory cyclic stability of 92.1 % at current density of 10 mA·cm−2 after 10,000 cycles. In general, the work demonstrates the significance of NiCo 2 S 4 /MnO 2 -60 as a highly redox active electrode material for future practical application in supercapacitors. [ABSTRACT FROM AUTHOR]