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Chemical Research in Chinese Universities 2014年第3期30卷 409-414页

作者： zhu Hongwei wang Baolei ZHANG Xiulan XIONG Lixia YU Shujing LI Zhengming State Key Laboratory of Elemento-organic Chemistry Research Institute of Elemento-organic Chemistry Nankai University Tianjin 300071 P. R. China

A series of novel 3-bromo-1-（3-chloropyridin-2-yl）-N-hydroxy-N-aryl-lH-pyrazole-5-carboxamides was synthesized by the reaction of pyrazole carbonyl chloride with each of substituted phenylhydroxyamines. The latter ones were prepared in good yields by reducing substituted nitrobenzene compounds with Zn/NH4CI reductant system in alcohol. Structures of the title compounds were determined by IR, 1H NMR, and HRMS. Their insecticidal and fungicidal activities were evaluated by larvicidal test against oriental armyworm and the mycelium growth rate method, respectively.

关键词： N-Hydroxyl amide N-Pyridylpyrazole Insecticidal activity Fungicidal activity

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen Yuan Lei Lei Yuan-zhu wang Bo wang Yi-Ying wang Chao Chen Zhao-Qiang Shen Yi-Fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

Identification, isolation and characterization of the antifeedant constituent of Clausena anisata against Helicoverpa armigera （Lepidoptera： Noctuidae）

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Insect Science 2009年第3期16卷 247-253页

作者： Olufemi O. R. Pitan O. O. Ayelaagbe Hong-Lei wang Chen-zhu wang State Key Laboratory of Integrated Management of Pest insects and Rodents Institute of Zoology Chinese Academy of Sciences BeijingChina Department of Crop Protection University of Agriculture Abeokuta Department of Chemistry University of Ibadan IbadanNigeria

Hexane, petroleum ether, chloroform, ethyl acetate, methanol and water extracts of Clausena anisata [（Willd.） Hook E Ex Benth] leaves and roots were evaluated against Helicoverpa armigera （Hubner） for antifeedant activities. Antifeedant activity was confirmed, and was found to be higher in root extracts than those of the leaf. Chloroform and petroleum ether extracts of the root showed strongest antifeedant activities （DC50s [concentration （C） causing 50% deterrence compared with the control] 0.014% and 0.016% respectively）, and root extracts were fractionated using silica gel column chromatography. One fraction of the chloroform and one of the petroleum ether root extracts was active; and on the basis of mass spectroscopy and ^1H and ^13C nuclear magnetic resonance spectral data, the active compounds in the two fractions were confirmed to be identical, and identified as osthol [2H-1-Benzopyran-2-one, 7-methoxy-8-（3-methyl-2-butenyl）]. The highest concentration of osthol was found in the chloroform root extract. Antifeedant activities of the root extracts, as measured by DC50 values, were highly correlated with their osthol contents. Approximately 99% of the variation in bioactivity of the root extracts could be accounted for by variation in osthol content; osthol therefore, appeared to be an antifeedant component of C. anisata to H. armigera. This may provide a new approach to managing this pest.

关键词： active ingredient antifeedant Clausena anisata Helicoverpa armigera,osthol root

Radionuclides in primary coolant of a fluoride salt-cooled hightemperature reactor during normal operation

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Nuclear Science and Techniques 2017年第3期28卷 109-114页

作者： Guo-Qing Zhang Shuai wang Hai-Qing Zhang Xing-wang zhu Chao Peng Jun Cai Zhao-Zhong He Kun Chen Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

The release of fission products from coated particle fuel to primary coolant, as well as the activation of coolant and impurities, were analysed for a fluoride saltcooled high-temperature reactor(FHR) system, and the activity of radionuclides accumulated in the coolant during normal operation was calculated. The release rate(release fraction per unit time) of fission products was calculated with STACY code, which is modelled mainly based on the Fick's law, while the activation of coolant and impurities was calculated with SCALE code. The accumulation of radionuclides in the coolant has been calculated with a simplified model, which is generally a time integration considering the generation and decay of radionuclides. The results show that activation products are the dominant gamma source in the primary coolant system during normal operation of the FHR while fission products become the dominant source after shutdown. In operation condition,health-impacts related nuclides such as ~3H, and ^(14)C originate from the activation of lithium and coolant impurities including carbon, nitrogen, and oxygen. According to the calculated effective cross sections of neutron activation,~6Li and ^(14)N are the dominant ~3H production source and ^(14)C production source, respectively. Considering the high production rate,~3H and ^(14)C should be treated before being released to the environment.

关键词： Source term FHR Primary coolant Fick’s law Diffusion

Landscape of cell heterogeneity and evolutionary trajectory in ulcerative colitis-associated colon cancer revealed by single-cell RNA sequencing

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Chinese Journal of Cancer Research 2021年第2期33卷 271-288页

作者： Quan wang zhu wang Zhen Zhang Wei Zhang Mengmeng Zhang Zhanlong Shen Yingjiang Ye Kewei Jiang Shan wang Department of Gastroenterological Surgery Peking University People’s HospitalBeijing 100044China Laboratory of Surgical Oncology Beijing Key Laboratory of Colorectal Cancer Diagnosis and Treatment ResearchPeking University People’s HospitalBeijing 100044China Department of Gastrointestinal Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China

Objective:The goal of this study was to get preliminary insight on the intra-tumor heterogeneity in colitisassociated cancer(CAC)and to reveal a potential evolutionary trajectory from ulcerative colitis(UC)to CAC at the single-cell ***:Fresh samples of tumor tissues and adjacent UC tissues from a CAC patient with pT3N1M0 stage cancer were examined by single-cell RNA sequencing(scRNA-seq).Data from The Cancer Genome Atlas(TCGA)and The Human Protein Atlas were used to confirm the different expression levels in normal and tumor tissues and to determine their relationships with patient ***:Ultimately,4,777 single-cell transcriptomes(1,220 genes per cell)were examined,of which 2,250(47%)and 2,527(53%)originated from tumor and adjacent UC tissues,*** defined the composition of cancer-associated stromal cells and identified six cell clusters,including myeloid,T and B cells,fibroblasts,endothelial and epithelial *** pathways and transcription factors involved in these cell clusters were analyzed and ***,the precise cellular composition and developmental trajectory from UC to UCassociated colon cancer were graphed,and it was predicted that CD74,CLCA1,and DPEP1 played a potential role in disease ***:scRNA-seq technology revealed intra-tumor cell heterogeneity in UC-associated colon cancer,and might provide a promising direction to identify novel potential therapeutic targets in the evolution from UC to CAC.

关键词： Ulcerative colitis-associated colon cancer single-cell RNA sequencing cell heterogeneity evolutionary trajectory

Investigations on mesa width design for 4H–SiC trench super junction Schottky diodes

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Chinese Physics B 2018年第8期27卷 466-475页

作者： Xue-Qian Zhong Jue wang Bao-zhu wang Heng-Yu wangC Qing Guo Kuang Sheng College of InFormatiOn College of Electrical Eneinee in.and Electrical EngineeringZhejiang University City CollegeHangzhou 310015China

Mesa width （WM） is a key design parameter for SiC super junction （SJ） Schottky diodes （SBD） fabricated by the trench-etching-and-sidewall-implant method. This paper carries out a comprehensive investigation on how the mesa width design determines the device electrical performances and how it affects the degree of performance degradation induced by process variations. It is found that structures designed with narrower mesa widths can tolerant substantially larger charge imbalance for a given BV target, but have poor specific on-resistances. On the contrary, structures with wider mesa widths have superior on-state performances but their breakdown voltages are more sensitive to p-type doping variation. Medium WM structures （-2 p.m） exhibit stronger robustness against the process variation resulting from SiC deep trench etching. Devices with 2-p.m mesa width were fabricated and electrically characterized. The fabricated SiC SJ SBDs have achieved a breakdown voltage of 1350 V with a specific on-resistance as low as 0.98 mΩ***2. The estimated specific drift on- resistance by subtracting substrate resistance is well below the theoretical one-dimensional unipolar limit of SiC material. The robustness of the voltage blocking capability against trench dimension variations has also been experimentally verified for the proposed SiC SJ SBD devices.

关键词： silicon carbide super junction Schottky diode trench etching

Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： Zhen Zhang Lin-na Feng Jin-he wang Zheng-kun Li Hua-meng Fu Hong Li Zheng-wang zhu Hai-feng Zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

Protection of Veratrum nigrum *** Nakai alkaloids against ischemia-reperfusion injury of the rat liver

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World Journal of Gastroenterology 2007年第4期13卷 564-571页

作者： Zhen-Zhen wang Wei-Jie Zhao Xue-Song Zhang Xiao-Feng Tian Yu-zhu wang Feng Zhang Jin-Chan Yuan Guo-zhu Han Ke-Xin Liu Ji-Hong Yao Department of Pharmacology Dalian Medical University Dalian 116027 Liaoning Province China Department of Chemical Pharmaceutics Dalian University of Science and Technology Dalian 116027 Liaoning Province China Department of General Surgery Second Affiliated Hospital of Dalian Medical University Dalian 116023 Liaoning Province China

AIM： TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids （VnA） on hepatic ischemia/reperfusion （I/R） injury in rats. METHODS： Forty male Wistar rats were randomly divided into four experimental groups （n = 10 in each）：（A） Control group （the sham operation group）; （8） I/R group （pretreated with normal saline）; （C） Small-dose （10 μg/kg） VnA pretreatment group; （D） Large-dose （20 μg/kg） VnA pretreatment group. Hepatic ischemia/ reperfusion （Hepatic I/R） was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase （SOD） activity, myeloperoxidase （MPO） activity and nitric oxide （NO） content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 （ICAM-1） and E-selectin （ES） were detected by immunohistochemical examinations and Western blot analyses. RESULTS： The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase （ALT： 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P 〈 0.01） and lactic dehydrogenase （LDH： 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P 〈 0.01）, as well as the levels of MPO （1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P 〈 0.01） and NO （69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P 〈 0.01） in the liver tissue, all of which were reduced by pretreatment with VnA, respectively （ALT： 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P 〈 0.01, P 〈 0.01; LDH： 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P 〈 0.01, P 〈 0.01; MPO： 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g, 2.07 ± 0.05 U/g, P 〈 0.01, P 〈 0.01; NO： 78.39 ± 2.28 μmol/g protein vs 71.11 ± 1.73 μmol/g

关键词： Veratrum nigrum L.var. ussuriense Nakaialkaloids Hepatic Ischemia/Reperfusion Injury Intracellular adhesion molecule-i E-selectin

Investigation of the deterioration of passive films in H_2S-containing solutions

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International Journal of Minerals,Metallurgy and Materials 2017年第8期24卷 943-953页

作者： zhu wang Lei Zhang Xian Tang Zhao-yang Cui Jun-peng Xue Min-xu Lu Institute of Advanced Materials and Technology University of Science and Technology Beijing Safetech Research Institute

The effect of H_2S on the corrosion behavior of 316 L stainless steel was investigated using electrochemical methods by changing the gas condition from CO_2 to H_2S and then back to CO_2. The presence of H_2S showed an acceleration effect on the corrosion of 316 L stainless steel in comparison with CO_2. The acceleration effect remained even after the complete removal of H_2S by CO_2, indicating that the passive film was irreversibly damaged. X-ray photoelectron spectroscopy(XPS) analysis indicated that the passive film was composed of Cr_2O_3, Fe_2O_3, and FeS_2 after being immersed in H_2S-containing solutions. The semiconducting property of the passive film was then investigated by using the Mott–Schottky approach. The presence of sulfides resulted in higher acceptor and donor densities and thus was responsible for the deterioration of passive films.

关键词： stainless steel passive films hydrogen sulfide corrosion

WeiTsing: a new face of Ca^(2+)-permeable channels in plant immunity

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Stress Biology 2023年第1期3卷 283-287页

作者： Feng-zhu wang Jian-Feng Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-Sen UniversityGuangzhou 510275China

Plants employ pattern-and effector-triggered immunity(PTI and ETI)to synergistically defend invading pathogens and insect *** PTI and ETI can induce cytosolic Ca^(2+)spikes,despite in different spatiotemporal patterns,to activate downstream Ca^(2+)-dependent immune signaling *** multiple families of Ca^(2+)-permeable channels at the plasma membrane have been uncovered,the counterparts responsible for Ca^(2+)release from intracellular stores remain poorly *** a groundbreaking paper published recently by Cell,the authors reported that WeiTsing,an Arabidopsis endoplasmic reticulum(ER)-resident protein that was specifically expressed in the pericycle upon Plasmodiophora brassicae(Pb)infection,could form resistosome-like Ca^(2+)-conducting channel and protect the stele of Brassica crops from Pb *** the channel activity of WeiTsing was indispensable for its immune function,the findings highlight a previously underappreciated role of Ca^(2+)release from intracellular repertoire in promoting plant disease resistance.

关键词： Plant immunity Ca^(2+)-permeable channel Endoplasmic reticulum Plasmodiophora brassicae Brassica crop