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A new alkaloid from Solanum cathayanum

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Chinese Chemical Letters 2008年第1期19卷 68-70页

作者： Fan Cheng Xiang Li jun zhi wang Hubei Key Laboratory of Natural Products Research and Development College of Chemistry and Life Science China Three Gorges University Yichang 443002 China Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

A new alkaloid compound I was obtained from Solanum cathayanum, a folk medicine of Hubei Province, together with a known alkaloid, orotic acid ethyl ester. On the basis of spectroscopic data and chemical methods, I was identified as 8-hydroxy-3-methoxy- 5H-pyrido[2, 1-c]pyrazin-5-one. Compound I can inhibit the production of NO in peritoneal macrophage of mice induced with LPS. The content of NO was determined by enzyme methods. 2007 jun zhi wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Alkaloid Solarium cathayanum Folk medicine Nitrogen monoxide

Infrared Characteristics of Associated Sources of Water Masers

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Chinese Journal of Astronomy and Astrophysics 2005年第6期5卷 587-594页

作者： Jarken Esimbek Yue-Fang Wu jun-zhi wang Department of Astronomy Peking University Beijing 100871 National Astronomical Observatories/Urumqi Observatory Chinese Academy of SciencesUrumqi 830011

We present an analysis of the infrared properties of 1417 water masers collected from the literature published by December 2004. The associated infrared sources of the water masers were identified with IRAS and MSX （Midcourse Space Experiment） catalogues. There are 1252 water masers associated with IRAS sources within 11, which include 700 interstellar and 552 stellar sources. For 382 sources, the IRAS counterpart identification and the maser classification are new. We found the colors of the interstellar maser sources are much redder than those of the stellar ones at IRAS wavelength bands; 99% of the interstellar maser sources are above black body line, while 95% of the stellar masers are below. The distribution difference of the two kinds of masers shown in the color-color diagram is due to their different optical depths and temperature distributions of dust regions. There are 743 water masers with MSX counterparts, of which 552 are interstellar masers and 191 are stellar masers. MSX colors of the associated sources of water masers are here analyzed for the first time. The color differences among the MSX bands are small and the interstellar masers are redder than the stellar masers. There is a correlation between the intensity of the stellar water maser emission and that of the 12μm and 25μm emissions, while there is no correlation between the water maser emission and the 8μm emission. The infrared intensity increases with increasing wavelength for the interstellar masers, while it is the opposite for stellar masers. These results may provide clues for the pumping of water maser and for the properties of the two kinds of maser emission regions.

关键词： masers - ISM kinematics and dynamics - stars mass loss

Tailoring microstructures of CoCrFeNiNb_(0.25)hypoeutectic high-entropy alloy by hot deformation

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Rare Metals 2022年第6期41卷 2028-2037页

作者： Xiao-Rong Liu Feng He jun-Jie Li Ying-Ying Dang zhi-jun wang Jin-Cheng wang School of Materials Scienceand Engineering Northwestern Polytechnical UniversityXi'an710072China Thermal Power Research Institute Xi'an710054China

CoCrFeNiNb_(0.25)hypoeutectic high-entropy alloy(HEA)has shown good mechanical ***,due to interdendritic eutectics,it is challenging to further optimize the microstructure through cold rolling and *** current study showed that hot defor-mation effectively tailored the hypoeutectic *** investigated the hot deformation behavior and microstructure evolution of the dual-phase CoCrFe-NiNb_(0.25) HEA at different temperatures from 800 to 1000℃and different strain rates from 0.01 to 10.00 s^(-1).The systematic investigation showed the deformation activation energy around 500 kJ·mol^(-1).Microstructure with refined grains and uniformly distributed Laves phases can be obtained after 70%compression at 900℃with a strain rate of 0.01 s^(-1).

关键词： Hot deformation High-entropy alloy Microstructure evolution

Microstructural refinement and performance improvement of Cu-36 wt%Zn alloy by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring

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Rare Metals 2022年第10期41卷 3560-3565页

作者： Ya-Bo Fu Yi-Ping Lu zhi-jun wang zhi-Qiang Cao Ai-Jiao Xu School of Physics and Electronic Engineering Taizhou UniversityTaizhou318000China School of Materials Science and Engineering Dalian University of TechnologyDalian116024China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an710048China

Cu-36 wt%Zn alloy is widely used in valves of water and heating and auto parts,***,the structure is still coarse,and performances are much *** structure and performances of Cu-36 wt%Zn alloy were investigated by adding Al_(2)O_(3)nanoparticles and *** indicate that by Al_(2)O_(3)nanoparticles coupling electromagnetic stirring,the Cu-36 wt%Zn alloy with refined microstructure was successfully *** average grain size is refined by 99%compared with that without nanoparticles and *** tensile strength(R_m)and percentage elongation after fracture(A11.3)increase by 20.58%and 19.40%,respectively,compared with that without nanoparticles and *** increase heterogeneous nucleation rate by 50%compared with that without *** depth of dezincification layer decreases by 78.71%compared with that without nanoparticles and stirring,as protective layer(Cu-Al_(2)O_(3)-Zn)is completely formed around the grain boundaries.

关键词： Microstructural refinement Rotating electromagnetic field Mechanical performance Al_(2)O_(3)nanoparticles

Embryonic liver fordin is involved in glucose glycolysis of hepatic stellate cell by regulating PI3K/Akt signaling

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World Journal of Gastroenterology 2016年第38期22卷 8519-8527页

作者： Wei Tu Jin Ye zhi-jun wang Department of Gastroenterology Tongji HospitalTongji Medical College Huazhong University of Science and Technology Institute of Liver Diseases Tongji HospitalTongji Medical College Huazhong University of Science and Technology Department of Gastroenterology Union HospitalTongji Medical College Huazhong University of Science and Technology Institute of Liver Diseases Union HospitalTongji Medical College Huazhong University of Science and Technology

AIM To investigate the role of embryonic liver fordin(ELF) in liver fibrosis by regulating hepatic stellate cells(HSCs) glucose *** The expression of ELF and the glucose glycolysisrelated proteins were evaluated in activated HSCs. si RNA was used to silence ELF expression in activated HSCs in vitro and the subsequent changes in PI3K/Akt signaling and glucose glycolysis-related proteins were *** The expression of ELF increased remarkably in HSCs of the fibrosis mouse model and HSCs that were cultured for 3 wk in vitro. Glucose glycolysis-related proteins showed an obvious increase in the activated HSCs, such as phosphofructokinase, platelet and glucose transporter 1. ELF-si RNA, which perfectly silenced the expression of ELF in activated HSCs, led to the induction of glucose glycolysis-related proteins and extracellular matrix(ECM) components. Moreover, p Akt, which is an important downstream factor in PI3K/Akt signaling, showed a significant change in response to the ELF silencing. The expression of glucose glycolysisrelated proteins and ECM components decreased remarkably when the PI3K/Akt signaling was blocked by Ly294002 in the activated HSCs. CONCLUSION ELF is involved in HSC glucose glycolysis by regulating PI3K/Akt signaling.

关键词： Liver fibrosis Embryonic liver fordin PI3K/ Akt signaling Hepatic stellate cells Glucose glycolysis

Effect of Mo Addition on Corrosion Behavior of High-Entropy Alloys CoCrFeNiMo_x in Aqueous Environments

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 41-51页

作者： Xu-Liang Shang zhi-jun wang Qing-Feng Wu Jin-Cheng wang jun-Jie Li Jia-Kang Yu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The corrosion behavior of CoCrFeNiMo_x alloys was investigated in aqueous environments, NaCl and H_2SO_4 solutions,respectively, to simulate typical neutral and acidic conditions. The cyclic polarization curves in NaCl and the potentiodynamic curves in H_2SO_4 clearly reveal the beneficial effects of Mo and the detrimental effect of σ-phase on the corrosion resistance. The X-ray photoelectron spectroscopy results of CoCrFeNiMo_x alloys in H_2SO_4 solution indicate that Cr and Mo predominate the corroded surface of the alloys, where Mo primarily exists in the form of MoO_3.

关键词： High-entropy alloys Corrosion σ-phase Molybdenum

Effect of interface anisotropy on tilted growth of eutectics:A phase field study

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Chinese Physics B 2022年第10期31卷 563-571页

作者： Mei-Rong Jiang jun-Jie Li zhi-jun wang Jin-Cheng wang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Interfacial energy anisotropy plays an important role in tilted growth of eutectics. However, previous studies mainly focused on the solid-solid interface energy anisotropy, and whether the solid-liquid interface energy anisotropy can significantly affect the tilted growth of eutectics still remains unclear. In this study, a multi-phase field model is employed to investigate both the effect of solid-liquid interfacial energy anisotropy and the effect of solid-solid interfacial energy anisotropy on tilted growth of eutectics. The findings reveal that both the solid-liquid interfacial energy anisotropy and the solid-solid interfacial energy anisotropy can induce the tilted growth of eutectics. The results also demonstrate that when the rotation angle is within a range of 30°-60°, the growth of tilted eutectics is governed jointly by the solid-solid interfacial energy anisotropy and the solid-liquid interfacial energy anisotropy;otherwise, it is mainly controlled by the solid-solid interfacial energy anisotropy. Further analysis shows that the unequal pinning angle at triple point caused by the adjustment of the force balance results in different solute-diffusion rates on both sides of triple point. This will further induce an asymmetrical concentration distribution along the pulling direction near the solid-liquid interface and the tilted growth of eutectics. Our findings not only shed light on the formation mechanism of tilted eutectics but also provide theoretical guidance for controlling the microstructure evolution during eutectic solidification.

关键词： tilted eutectics interfacial energy anisotropy multi-phase field model

mRNA cancer vaccines:Advances,trends and challenges

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Acta Pharmaceutica Sinica B 2022年第7期12卷 2969-2989页

作者： Qing He Hua Gao Dejiang Tan Heng Zhang jun-zhi wang National Institutes for Food and Drug Control State Key Laboratory for Evaluation and Standardization of Innovative Vaccines and Biotechnology ProductsBeijing 102629China

Patients exhibit good tolerance to messenger ribonucleic acid(m RNA)vaccines,and the choice of encoded molecules is flexible and *** vaccines can be engineered to express full-length antigens containing multiple epitopes without major histocompatibility complex(MHC)restriction,are relatively easy to control and can be rapidly mass *** 2021,the *** and Drug Administration(FDA)approved the first m RNA-based coronavirus disease 2019(COVID-19)vaccine produced by Pfizer and Bio NTech,which has generated enthusiasm for m RNA vaccine research and *** on the above characteristics and the development of m RNA vaccines,m RNA cancer vaccines have become a research hotspot and have undergone rapid development,especially in the last five *** review analyzes the advances in m RNA cancer vaccines from various perspectives,including the selection and expression of antigens/targets,the application of vectors and adjuvants,different administration routes,and preclinical evaluation,to reflect the trends and challenges associated with these vaccines.

关键词： mRNA Cancer vaccine Tumor-associated antigens Neoantigens mRNA delivery vectors Adjuvants Administration routes

Diastereoisomeric saponins from the rhizomes of Tupistra chinensis

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Chinese Chemical Letters 2007年第1期18卷 65-68页

作者： Kun Zou jun Wu Ming Du Chuang Liu Zi Chun Tang jun zhi wang Hubei Key Laboratory of Natural Products Research and Development College of Chemistry and Life Sciences. China Three Gorges University Yichang 443002 China Guangdong Key Laboratory of Marine Materia Medica. South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

A pair of diastereoisomeric furostanol saponins was obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes, a folk medicine of Shennongjia Forest District of Hubei Province. Their st... 详细信息

关键词： Tupistra chinensis Bak, Furostanol saponin Diastereoisomeric Folk medicines