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Monoclinicβ-AgVO_(3) coupled with CdS formed a 1D/1D p-n heterojunction for efficient photocatalytic hydrogen evolution

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Rare Metals 2023年第5期42卷 1494-1507页

作者： Xuan-Pu Wang zhi-liang Jin Xin Li School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan750021China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China

Improving the separation of photogenerated carriers and suppressing the rapid complication of electron-hole pairs are essential ways to improve photocatalytic hydrogen production *** high recombination rate of the photogenerated carriers is an issue encountered when developing CdS as a promising photocatalytic *** work allowed to accelerate the separation of photogenerated electrons and holes by loading monoclinicβ-AgVO_(3)on hexagonal CdS nanorods to construct a one-dimensional(1D)/1D p-n *** introduction of monoclinicβ-AgVO_(3)with a narrow band gap effectively improves the light absorption of CdS,which is conducive to improving the use of visible *** integrated electric field of the p-n heterojunction can effectively transfer electrons and holes in the direction suitable to hydrogen *** photoluminescence and electrochemical characterization of the catalysts showed that the p-n heterojunction formed after loadingβ-AgVO_(3)greatly improved the separation efficiency of *** hydrogen evolution experiments show that the composite catalyst has good photocatalytic hydrogen evolution capability and *** composite catalyst with the best photocatalytic performance was obtained by studyingβ-AgVO_(3)with different *** composite catalyst reached 581.5μmol of hydrogen amount within 5 h,which is 3.8 times higher than that of CdS alone and its apparent quantum efficiency reaches8.02%.The present work provides a possible solution for the development of perovskite and the extensiveness of CdS in photocatalytic hydrogen evolution.

关键词： Photocatalysis Hydrogen evolution p-n heterojunction AgVO_(3)

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Femtosecond Reflections of Bulk GaAs and GaAs/AlGaAs Multiple Quantum Wells

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Chinese Physics Letters 1996年第3期13卷 237-240页

作者： LI Wei-liang QIU zhi-ren PENG Wen-ji HUANG Xu-guang ZHOU Jian-ying YU Zhen-xin State Key Laboratory of Ultrafast Laser Spectroscopy Zhongshan UniversityGuangzhou 510275

We present room temperature femtosecond rejection studies on the photocarrier dynamics of GaAs and GaAs/AlGaAs multiple quantum wells(MQW).A rising wing with a time constant of about.5 ps and an increased amplitude per carrier is observed for the MQW sample at carrier densities lower than 5×10^(11) cm^(-2).This phenomenon is explained as the saturation of the excitonic transitions.

关键词： GaAs/AlGaAs Femto Quantum

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Periodic codings of algebraic graph-directed IFS

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Science China Mathematics 2015年第1期58卷 131-142页

作者： WEN zhi ying YANG Ya Min Department of Mathematical Sciences Tsinghua University College of Science Huazhong Agricultural University

We study the points with periodic codings of a class of graph-directed iterated function systems on with algebraic parameters （which we call algebraic GIFS）. It is shown that the set of points with periodic codings is closely related to the Rauzy box. Especially for the feasible Pisot GIFS, this set is completely characterized by the Rauzy box; this result unifies and extends the previous results on the study of periodic points of classical and generalized β-transformations.

关键词： algebraic GIFS periodic coding Rauzy box

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Diurnal variation of number concentration and size distribution of ultrafine particles in the urban atmosphere of Beijing in winter

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Journal of Environmental Sciences 2007年第8期19卷 933-938页

作者： SHI Zong-bo HE Ke-bin YU Xue-chun YAO zhi-liang YANG Fu-mo MA Yong-liang MA Rui JIA ying-tao ZHANG Jie Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China. TSI Asia Pacific Beijing Representative Beijing 100084 China College of Earth Sciences Graduate University-of Chinese Academy of Sciences Beijing 100049 China

Number concentration and distribution of airborne particles in the size range 5.6 to 560 nm diameter were measured in Beijing for a 15-d period in winter 2005. Dally average number concentrations of nucleation mode （5.6-20 um）, Aitken mode （20-100 um）, and accumulation mode （100-560 um） particles, and total particles were 17500, 32000, 4000, and 53500 cm^-3, respectively. Average particle size distribution was monomodal with a mode diameter of about 40 um at night and bimodal with mode diameters of about 10 and about 40 um during the daytime. New particle formation events, which were connected to diurnal variation of nucleation mode particles, were observed in more than half of the observation days. The events often started around 10：00-11：00 Chinese Standard Time （CST） and ended up after 3-4 h. Concentrations of Aitken and accumulation mode particles increased from midnight and reached their maxima at about 10：00 CST, and then decreased and became the lowest in the afternoon. Analysis of diurnal cycles in traffic volume and meteorological parameters revealed that the accumulation of the particles in Aitken and accumulation modes in the morning was influenced by formation of an inversion and increase in vehicle emission, and dispersion of such particles in the afternoon was associated with more effective vertical mixing and higher wind speed.

关键词： fine particles nucleation mode Aitken mode new particle formation

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Antitumor effects of artesunate on human breast carcinoma MCF-7 cells and IGF-IR expression in nude mice xenografts

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Chinese Journal of Cancer Research 2014年第2期26卷 200-207页

作者： Hai-ying Dong zhi-Fei Wang Department of Oncology Zhejiang People's Provincial Hospital Department of Hepatobiliary and Pancreatic Surgery Zhejiang People's Provincial Hospital

Purpose： The objective of this study was to investigate the anti-tumor effects and analyze the mechanism of artesunate （ART） action on breast cancer in vivo using tumor transplanted nude mice. Methods： The human breast tumor cell line MCF-7 was transplanted into nude mice, and the animals were treated with various doses of ART alone or in combination with cyclophosphamide （CTX） or normal saline （NS）. The tumor inhibitory effects were observed and compared, and the ultrastructural morphology of the transplanted tumor cells was observed by electron microscopy. The apoptosis rates and cell cycle status were detected by flow cytometry （FCM）. The expression of apoptosis-related proteins p53, Bcl-2, Bax and Caspase-3 were detected by immunohistochemistry and IGF-IR was detected by western blot. The expression correlation for these proteins was also analyzed. Results： The tumor inhibition rates in the low dose ART group, high dose ART group, CTX group and combined drug therapy group were （24.39±10.20）%, （40.24±7.02）%, （57.01±5.84）% and （68.29±5.1）%, respectively. The cell cycle was arrested in phase G0/Gt after treatment with ART. The expression of Bcl-2 was significantly reduced, and the expression levels of Bax and Caspase-3 were significantly increased in the ART group compared to the negative control saline group. There was no significant difference detected in p53 expression. The Bcl-2 level was negatively related to Bax and Caspase-3. The western blotting results showed IGF-IR downregulation. Conclusions： ART inhibits the growth of MCF-7 breast tumor cell xenografts in nude mice. The anti-tumor mechanism of ART for human breast carcinoma in nude mice might be correlated with the alteration of apoptosis related protein expression, which may further induce apoptosis and inhibit cell proliferation.

关键词： Artesunate (ART) nude mice anticancer effect cell apoptosis

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Wilson's Disease in China

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Neuroscience Bulletin 2017年第3期33卷 323-330页

作者： Juan-Juan Xie zhi-ying Wu Department of Neurology and Research Center of Neurologyin the Second Affiliated Hospital and the Collaborative Innovation Center for Brain ScienceZhejiang University School of MedicineHangzhou 310009China

Wilson＇s disease（WD） is an autosomal recessive disorder of copper metabolism. Its incidence is higher in China than in western countries. ATP7 B is the causative gene and encodes a P-type ATPase, which participates in the synthesis of holoceruloplasmin and copper excretion. Disease-causing variants of ATP7 B disrupt the normal structure or function of the enzyme and cause copper deposition in multiple organs,leading to diverse clinical manifestations. Given the variety of presentations, misdiagnosis is not rare. Genetic diagnosis plays an important role and has gradually become a routine test in China. The first Chinese spectrum of disease-causing mutations of ATP7 B has been established. As a remediable hereditary disorder, most WD patients have a good prognosis with an early diagnosis and chelation treatment. However, clinical trials are relatively few in China, and most treatments are based on the experience of experts and evidences from other countries. It is necessary to study and develop appropriate regimens specific for Chinese WD patients.

关键词： Wilson’s Disease Copper Epidemiology Pathogenesis Management

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Analytical approach to quantum phase transitions of ultracold Bose gases in bipartite optical lattices using the generalized Green＇s function method

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Frontiers of physics 2018年第4期13卷 195-208页

作者： zhi Lin Jun Zhang ying Jiang Department of Physics State Key Laboratory of Surface Physics and Laboratory of Advanced Materials Fudan University Shanghai 200433 China Department of Physics Shanghai University Shanghai 200444 China Qian Weichang College Shanghai University Shanghai 200444 China Key Lab for Astrophysics Shanghai 200234 China

In order to investigate the quantum phase transitions and the time-of-flight absorption pictures analyt- ically in a systematic way for ultracold Bose gases in bipartite optical lattices, we present a generalized Green＇s function method. Utilizing this method, we study the quantum phase transitions of ultracold Bose gases in two types of bipartite optical lattices, i.e., a hexagonal lattice with normal Bose-Hubbard interaction and a d-dimensional hypercubic optical lattice with extended Bose-Hubbard interaction. Furthermore, the time-of-flight absorption pictures of ultracold Bose gases in these two types of lat- tices are also calculated analytically. In hexagonal lattice, the time-of-flight interference patterns of ultracold Bose gases obtained by our analytical method are in good qualitative agreement with the exDerimental results of Soltan-Panahi, et al. [Nat. Phys. 7, 434 （2011）]. In square optical lattice, the emergence of peaks at（±π/a,±π/a） in the time-of-flight absorption pictures, which is believed to bea sort of evidence of the existence of a supersolid phase, is clearly seen when the system enters the compressible phase from charge-density-wave phase.

关键词： ultracold Bose gases quantum phase transition bipartite optical lattice generalizedGreen's function method time-of-flight absorption picture

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A New Triterpenoid Saponin from Codonopsis lanceolata

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Chinese Chemical Letters 2006年第11期17卷 1460-1462页

作者： Zhong YUAN zhi Min liang School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016

A new triterpenoid saponin, named codonolaside （1） was isolated from the root of Codonopsis lanceolata. Its structure was determined by analysis of its spectral and chemical data.

关键词： Codonopsis lanceolata triterpenoid saponin codonolaside.

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Release behavior and kinetic evaluation of berberine hydrochloride from ethyl cellulose/chitosan microspheres

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Frontiers of Materials Science 2014年第4期8卷 373-382页

作者： Hui-Yun ZHOU Pei-Pei CAO Jie ZHAO zhi-ying WANG Jun-Bo LI Fa-liang ZHANG Chemical Engineering & Pharmaceutics College Henan University of Science and Technology Luoyang 471023 China

Novel ethyl cellulose/chitosan microspheres （ECCMs） were prepared by the method of w/o/w emulsion and solvent evaporation. The microspheres were spherical, adhesive, and aggregated loosely with a size not bigger than 5 pm. The drug loading efficiency of berberine hydrochloride （BH） loaded in microspheres were affected by chitosan （CS） concentration, EC concentration and the volume ratio of V（CS）/V（EC）. ECCMs prepared had sustained release efficiency on BH which was changed with different preparation parameters. In addition, the pH value of release media had obvious effect on the release character of ECCMs. The release rate of BH from sample B was only a little more than 30% in diluted hydrochloric acid （dHCl） and that was almost 90% in PBS during 24 h. Furthermore, the drug release data were fitted to different kinetic models to analyze the release kinetics and the mechanism from the microspheres. The released results of BH indicated that ECCMs exhibited non-Fickian diffusion mechanism in dHCI and diffusion-controlled drug release based on Fickian diffusion in PBS. So the ECCMs might be an ideal sustained release system especially in dHCl and the drug release was governed by both diffusion of the drug and dissolution of the polymeric network.

关键词： ethyl cellulose (EC) chitosan (CS) microsphere release in vitro releasekinetics

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Spur Gear Tooth Pitting Propagation Assessment Using Model-based Analysis

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1369-1382页

作者： Xi-Hui liang zhi-liang Liu Jun Pan Ming Jian Zuo Department of Mechanical Engineering University of Alberta School of Mechatronics Engineering University of Electronic Science and Technology Key Laboratory of Reliability Technology for Mechanical and Electrical Product of Zhejiang Province Zhejiang Sci-Tech University

Tooth pitting is a common failure mode of a gearbox. Many researchers investigated dynamic properties of a gearbox with localized pitting damage on a single gear tooth. The dynamic properties of a gearbox with pitting distributed over multiple teeth have rarely been investi- gated. In this paper, gear tooth pitting propagation to neighboring teeth is modeled and investigated for a pair of spur gears. Tooth pitting propagation effect on time-vary- ing mesh stiffness, gearbox dynamics and vibration char- acteristics is studied and then fault symptoms are revealed. In addition, the influence of gear mesh damping and environmental noise on gearbox vibration properties is investigated. In the end, 114 statistical features are tested to estimate tooth pitting growth. Statistical features that are insensitive to gear mesh damping and environmental noise are recommended.

关键词： Mesh stiffness Mesh damping Geardynamics Vibration Statistical feature Dynamicsimulation

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