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Chinese Physics B 2024年第6期33卷 596-603页

作者：吕小龙杨加恩谢航 College of Science Guangxi University of Science and TechnologyLiuzhou 545006China College of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly-Coupled Physics Chongqing UniversityChongqing 401331China

Topological zero-line modes(ZLMs) with spin and valley degrees of freedom give rise to spin, valley and spinvalley transport, which support a platform for exploring quantum transport physics and potential applications in spintronic/valleytronic devices. In this work, we investigate the beam-splitting behaviors of the charge current due to the ZLMs in a three-terminal system. We show that with certain combinations of ZLMs, the incident charge current along the interface between different topological phases can be divided into different polarized currents with unit transmittance in two outgoing terminals. As a result, fully spin-polarized, valley-polarized and spin-valley-polarized electron beam splitters are generated. The mechanism of these splitters is attributed to the cooperative effects of the distribution of the ZLMs and the intervalley and intravalley scatterings that are modulated by the wave-vector mismatch and group velocity mismatch. Interestingly, half-quantized transmittance of these scatterings is found in a fully spin-valley-polarized electron beam ***, the results indicate that these splitters can be applicable to graphene, silicene, germanene and stanene due to their robustness against the spin–orbit coupling. Our findings offer a new way to understand the transport mechanism and investigate the promising applications of ZLMs.

关键词： topological zero-line modes spin polarization valley polarization quantum transport

Influences of enteral nutrition combined with probiotics on gut microflora and barrier function of rats with abdominal infection

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World Journal of Gastroenterology 2006年第27期12卷 4352-4358页

作者： Tong-Yi Shen Huan-long Qin Zhi-Guang Gao Xiao-Bing Fan Xiao-Ming hang Yan-Qun Jiang Department of Surgery Shanghai Sixth People's Hospital Affiliated to Shanghai Jiaotong University Shanghai 200233 China

AIM： To investigate the influences of enteral, parenteral nutrition and probiotics delivered by gut on intestinal microecology, epithelial tight junctions, immune and barrier function of rats with abdominal infection. METHODS： Rat abdominal infection models established with cecal ligation and perforation method, were divided into three groups： parenteral nutrition （PN group, n = 7）, PN＋enteral nutrition （EN group, n = 7） and PN ＋ EN ＋ probiotics （probiotics group, n = 7） via the needle jejunostomy and neck vein for five days. The total nutritional supplement of the three groups was isonitrogenic and isocaloric. Probiotics was delivered by jejunostomy 10 mL/d （1 x 10^8 cfu/mL）. The rats were killed on the sixth day. The feces in the cecum were cultured for anaerobic bacterial growth and analyzed with bacterial group DNA fingerprint profile with random amplified polymorphic DNA. The transmembrane binding proteins （occludin） and IgA level in plasma cells of intestine epithelium in colon and terminal ileum were measured by an immunohistochemistry method. The ultrastructure of intestinal epithelial tight junctions in colon and small intestine was observed by electronmicroscopy. Vena cava blood and the homogenated tissue of liver, lung and mesenteric lymph nodes were cultured to determine the bacterial translocations, and endotoxin in the blood from portal vein was detected. RESULTS：（1） The amount of bacteria of gut species in EN group and probiotic group was higher than that in PN group. The DNA-proflles in EN group and probiotic group were similar to that of normal rats. The number of DNAprofiles in probiotics group was much more than that in PN group and EN group. Moreover, there were strange stripes in PN group. （2） The expression of occludin and IgA in the small and large intestine in EN group （2.309 ± 0.336, 15.440 ± 2.383） and probiotic group （2.938 ± 0.515, 16.230 ± 3.183） was improved as compared with PN group （1.207 ± 0.587, P 〈 0.05, 11.189 ± 2.108, P 〈 0.

关键词： Probiotics Enteral nutrition Gut flora Transmembrane binding proteins Gut barrier function

Image processing based three-dimensional model reconstruction for cross-platform numerical simulation

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China Foundry 2023年第2期20卷 139-147页

作者： Yu-cheng Sun Yu-hang Huang Na Li Xiao Han Ai-long Jiang Jin-wu Kang Ji-wu Wang Hai-liang Yu State Key Laboratory of Engine Reliability Weichai Power Co.Ltd.Weifang 261061ShandongChina School of Mechanical Engineering Central South UniversityChangsha 41000China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory for Advanced Materials Processing Technology School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Numerical simulation is the most powerful computational and analysis tool for a large variety of engineering and physical *** a complex problem relating to multi-field,multi-process and multi-scale,different computing tools have to be developed so as to solve particular fields at different scales and for different ***,the integration of different types of software is ***,it is difficult to perform the transfer of the meshes and simulated results among software packages because of the lack of shared data formats or encrypted data *** image processing based method for three-dimensional model reconstruction for numerical simulation was proposed,which presents a solution to the integration problem by a series of slice or projection images obtained by the post-processing modules of the numerical simulation *** means of mapping image pixels to meshes of either finite difference or finite element models,the geometry contour can be extracted to export the stereolithography *** values of results,represented by color,can be deduced and assigned to the *** the models with data can be directly or indirectly integrated into other software as a continued or new numerical *** three-dimensional reconstruction method has been validated in numerical simulation of castings and case studies were provided in this study.

关键词： cross-platform numerical simulation 3D model reconstruction image processing slice

New hybrid FDTD algorithm for electromagnetic problem analysis

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Chinese Physics B 2019年第7期28卷 211-215页

作者： Xin-Bo He Bing Wei Kai-hang Fan Yi-Wen Li Xiao-long Wei School of Physics and Optoelectronic Engineering Xidian University Xi'an 710071 China Collaborative Innovation Center of Information Sensing and Understanding at Xidian University Xi'an 710071 China Science and Technology on Plasma Dynamic Laboratory Airforce Engineering University Xi'an 710038 China

Since the time step of the traditional finite-difference time-domain(FDTD) method is limited by the small grid size, it is inefficient when dealing with the electromagnetic problems of multi-scale ***, the explicit and unconditionally stable FDTD(US-FDTD) approach has been developed to break through the limitation of Courant–Friedrich–Levy(CFL) ***, the eigenvalues and eigenvectors of the system matrix must be calculated before the time iteration in the explicit ***, the eigenvalue decomposition is also time consuming, especially for complex electromagnetic problems in practical *** addition, compared with the traditional FDTD method, the explicit US-FDTD method is more difficult to introduce the absorbing boundary and plane *** solve the drawbacks of the traditional FDTD and the explicit US-FDTD, a new hybrid FDTD algorithm is proposed in this *** combines the explicit US-FDTD with the traditional FDTD, which not only overcomes the limitation of CFL condition but also reduces the system matrix dimension, and introduces the plane wave and the perfectly matched layer(PML) absorption boundary *** the hybrid algorithm, the calculation of the eigenvalues is only required in the fine mesh region and adjacent coarse mesh ***, the calculation efficiency is greatly ***, the plane wave and the absorption boundary introduction of the traditional FDTD method can be directly *** results demonstrate the effectiveness, accuracy, stability, and convenience of this hybrid algorithm.

关键词： unconditionally stable hybrid FDTD algorithm electromagnetic problem

Chiral Br?nsted acid-catalyzed asymmetric intermolecular[4+2]annulation of ynamides with para-quinone methides

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Science China Chemistry 2023年第5期66卷 1467-1473页

作者： hang-Hao Li Ya-Nan Meng Can-Ming Chen Yu-Qi Wang Zhi-Xin Zhang Zhou Xu Bo Zhou long-Wu Ye Key Laboratory for Chemical Biology of Fujian Province and State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 221004China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China State Key Laboratory of Organometallic Chemistry Chinese Academy of SciencesShanghai 200032China

Catalytic asymmetric transformations of ynamides have attracted considerable attention in recent ***,most of them were limited to intramolecular reactions or required metal ***,a chiral Br?nsted acid-catalyzed asymmetric intermolecular[4+2]annulation of ynamides with para-quinone methides(p-QMs)is disclosed,which not only represents the first metal-free protocol for catalytic asymmetric nucleophilic addition of ynamides to electrophiles,but also constitutes the first enantioselective annulation between p-QMs and *** methodology leads to the practical synthesis of biologically important chiral 4-aryl-3,4-dihydrocoumarins and *** control experiments indicate that the orthohydroxyphenyl substituted p-QMs could isomerize into ortho-quinone methides(o-QMs)in the presence of chiral catalyst,which further react with ynamides via enantioselective[4+2]annulation,to generate the chiral product.

关键词： stereoselective metal-free cyclization ynamides p-QMs

long-term semi-autonomous orbit determination supported by a few ground stations for navigation constellation

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1342-1353页

作者： YI hang XU Bo GAO YouTao WANG JiaSong State Key Laboratory of Astronautics Dynamics Xi'an 710043 China College of Astronautics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Astronomy Department of Nanjing University Nanjing 210093 China

In view of the present technology of autonomous orbit determination for navigation satellite constellation(NSC) and the geographical conditions of China,we propose a long-term semi-autonomous orbit determination scheme supported by a few ground stations for NSC in this *** the effect of rotation and translation of the entire constellation relative to the inertial reference frame can bring large errors to the autonomous orbit determination using only cross-link range measurement,a few ground stations(such as 1-3) are supposed to construct the connection between the NSC and the *** by such a few ground stations,the NSC can realize long-term orbit determination called semi-autonomous orbit *** simulation results based on the IGS ephemeris indicate that,for a certain degree of measurement errors,the NSC can maintain its semi-autonomous orbit determination in a period of 240 days within 5 meters of URE.

关键词： navigation constellation cross-link range measurement semi-autonomous orbit determination a few ground stations

Single transition-metal atoms anchored on a novel Diracdispersiveπ-πconjugated holey graphitic carbon nitride substrate:computational screening toward efficient bifunctional OER/ORR electrocatalysts

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Rare Metals 2024年第8期43卷 3819-3832页

作者： Chun-Yao Fang Xi-hang Zhang Qiang Zhang Di Liu Xiao-Meng Cui Jing-Cheng Xu Cheng-long Shi Meng-Yu Yang College of Science University of Shanghai for Science and TechnologyShanghai 200093China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China

Nonprecious-metal-group single-metal-atom catalysts with bifunctional catalytic capabilities toward the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)are highly sought after in energy-conversion and storage ***,producing renewable and sustainable energy sources remains ***,single-transition metal atoms anchored onπ-πconjugated two-dimensional(2D)graphitic carbon nitride substrates formπ-d conjugated conductive channels that enhance the overall electrocatalytic ***,firstprinciples calculations were carried out to design and demonstrate a novel macropore graphitic carbon nitride(gC_(10)N_(3))as a promising 2D electrocatalyst substrate to support single-transition metal(TM,from Sc to Au).The"donation-acceptance"charge interaction in the TM-N_(2)moiety effectively balances the adsorption strength of oxygenated intermediates in Ni@g-C_(10)N_(3)and Rh@gC_(10)N_3,making them effective bifunctional OER/ORR electrocatalysts with IrO_(2)/Pt-beyond overpotentials being as low as 0.39/0.38 V and 0.54/0.44 V,***,they possess high stability and conductivity and are less susceptible to oxidation and corrosion under working *** guarantees high activity under ambient ***,the origin of the OER/ORR activity of TM@g-C_(10)N_(3) is explained using multilevel descriptors:intrinsic(p,Bader charge,integral crystal orbital Hamilton population(ICOHP),bond length,and d-band center(εd).In particular,for optimal Ni@g-C_(10)N_(3),the clear hybridization between the Ni-d orbital and surface O-p orbital causes the paired electrons to occupy the bonding *** enables OH~*to be adsorbed on the Ni@g-C_(10)N_(3),thereby achieving the highest catalytic performance.

关键词： First-principles calculation Oxygen evolution reaction Oxygen reduction reaction Bifunctional electrocatalysts Single-metal-atom electrocatalysts

A review of mechanism and technology of vanadium extraction from strategic mineral black shale

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Rare Metals 2024年第12期43卷 6183-6200页

作者： Yuan-hang Lu Jian-Kang Wen Xiao-Lan Mo Xin-long Yang Wen-Cheng Gao Hong-Ying Yang National Engineering Research Center for Environment-Friendly Metallurgy in Producing Premium Non-Ferrous Metals China GRINM Group Co. Ltd. School of Metallurgy Northeastern University GRINM Resources and Environment Tech.Co. Ltd. General Research Institute for Nonferrous Metals Beijing Engineering Research Center of Strategic Nonferrous Metals Green Manufacturing Technology GRIMAT Engineering Institute Co. Ltd.

Black shale represents' a unique and strategic vanadium resource in China,accounting for ～90% of the nation's vanadium *** complex forms of occurrence of vanadium in black shale,particularly its incorporation into aluminosilicate mica via isomorphism,render it tightly bound and challenging to *** the backdrop of green metallurgy and the "Double Carbon" initiative,methodologies such as the new roasting process,the whole hydrometallurgical process,and biological leaching have been developed,with their mechanisms thoroughly *** review examines the mechanisms of each process,highlighting that enhanced vanadium leaching is primarily achieved by disrupting the covalent bonds in vanadium-containing mica or by oxidizing lower-valence ***,the leaching mechanism of autotrophic microorganisms for black shale remains *** from various studies,a mechanism involving the cooperative action of iron-oxidizing and sulfur-oxidizing bacteria in the leaching of black shale is proposed.A comparative analysis of these enhancement processes reveals that microbial technology offers benefits such as environmental sustainability,low carbon footprint,minimal pollution,and scalability,marking it a promising area for research and ***,the technological processes and mechanisms underlying microbial leaching of black shale require further *** studies should focus on developing highly efficient leaching bacteria,exploring the synergistic effects between microorganisms and examining the mechanisms of biological leaching to provide technical and theoretical foundations for efficient and eco-friendly microbial extraction of vanadium from black shale.

关键词： Extraction

Efficacy and safety of Tripterygium wilfordii glycosides tablets combined with Western medicine for patients with rheumatic immune diseases

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World Journal of Clinical Cases 2025年第6期13卷 14-23页

作者： hang Shu Xiao-Yu Chen Jie Zhao Pin Li Zhen Sun Department of Traditional Chinese Medicine Hangzhou Special Service Recuperation Center of Chinese People's Liberation Army Air ForceNanjing 210000Jiangsu ProvinceChina Department of Convalescence Hangzhou Special Service Recuperation Center of Chinese People's Liberation Army Air ForceNanjing 210000Jiangsu ProvinceChina

BACKGROUND Rheumatic immune diseases are a group of chronic inflammatory diseases charac-terized by joint and systemic multi-organ involvement,including rheumatoid arthritis,systemic lupus erythematosus,and Sjogren’s syndrome,among *** pathogenesis of these diseases is related to the abnormal activation and regulatory imbalance of the immune *** prevalence and morbidity of rheumatic immune diseases are high,imposing a significant burden on patients'quality of life and socio-economic ***,the treatment of rheumatic immune diseases mainly relies on Western medicine,such as non-steroidal anti-inflammatory drugs,glucocorticoids,disease-modifying antirheumatic drugs,and ***,the therapeutic effects of Western medicine are not ideal,some patients poorly respond or are resistant to Western medicine,and long-term use often causes various adverse *** To systematically evaluate the efficacy and safety of Tripterygium wilfordii gly-cosides tablets combined with Western medicine in the treatment of patients with rheumatic immune *** This study conducted a meta-analysis to systematically evaluate the efficacy and safety of Tripterygium wilfordii glycosides tablets combined with Western medicine for patients with rheumatic immune *** and English databases were searched for randomized controlled trials(RCTs)on the treatment of rheumatic immune diseases with Tripterygium wilfordii glycosides tablets combined with Western *** quality of the included studies was assessed using the Cochrane risk of bias assessment ***-analysis was performed using RevMan 5.4 *** The meta-analysis included 11 RCTs involving 1026 patients with rheumatic immune *** combined treatment significantly reduced the risk of disease recurrence(relative risk=1.07,95%confidence interval:1.01-1.15,P<0.05)and showed no significant heterogeneity(I2=0%,P=0.53),indicating that Tripterygium wilfordii glycosides

关键词： Rheumatic immune diseases Tripterygium wilfordii polyglycosides tablets Western medicine treatment Systematic review Meta-analysis

Suppression of the regrowth interface leakage current in AlGaN/GaN HEMTs by Fe doped GaN substrate

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Science China(Information Sciences) 2024年第6期67卷 461-462页

作者： Xiao WANG Zhi-Yu LIN Yuan-hang SUN long YUE Yu-Min Zhang Jian-Feng WANG Ke XU School of Nano-Tech and Nano-Bionics University of Science and Technology of China Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences Information Materials Research Department Suzhou laboratory Suzhou Nanowin Science and Technology Co. Ltd. Jiangsu Institute of Advanced Semiconductors

In the process of homoepitaxy AlGaN/GaN heterojunction by metal-organic chemical vapor deposition (MOCVD) on free-standing substrates,Si impurities from the air and reaction chamber accumulate at the regrowth interfac... 详细信息

关键词： current interface hemts algan doped leakage regrowth substrate suppression