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A nonlinear regression model applied to kinetic multi-component analysis of esters with a SAW-impedance sensor

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Chinese Journal of Chemistry 1996年第6期14卷 525-531页

作者： Cai, QY peng, l Wang, RH Nie, lH Yao, SZ HUNAN UNIV DEPT CHEM & CHEM ENGNCHANGSHA 410082HUNANPEOPLES R CHINA

A kinetic nonlinear regression model for multi-component assay of esters was proposed based on their different alkaline-catalysed hydrolysis rate. The reaction rate was determined by monitoring the conductance change in solution with a liquid-purpose surface acoustic wave impedance sensor(SAW). The model was tested theoretically and experimentally with the mixture of methyl acetate and n-propyl acetate. The experimental detection limit of methyl acetate and n-propyl acetate (within 10 min) was 0.5 mu mol/l and 1.0 mu mol/l respectively and the recovery of the sensor system ranged from 93% to 106% (n=6).

关键词： surface acoustic wave nonlinear regression ester hydrolysis assay

The T-box Transcription Factor T-bet in Immunity and Autoimmunity

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Cellular & Molecular Immunology 2006年第2期3卷 87-95页

作者： Stanford l.peng Inflammation Autoimmunity and Transplantation ResearchRoche Palo AltoPalo AltoCAUSA

The T-box transcription factor T-bet （Tbx21） has emerged as a key regulator of type 1-like immunity, playing critical roles in the establishment and/or maintenance of effector call fates in T and B lymphocytes, as well as dendritic cells and natural killer calls. Several autoimmune diseases, especially those classically considered related to T helper 1 （Thl） immunity, appear to require T-bet, at least as judged in mouse models. This review summarizes a current understanding of T-bet＇s role in immunity, as wall as its importance in autoimmunity, with implications for therapeutic intervention.

关键词： transcription factor arthritis lupus inflammatory bowel disease diabetes multiple sclerosis

Determination of Cordycepin in Cordyceps kyushuensis by Capillary Electrophoresis and its Antitumour Activity

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Chinese Chemical letters 2003年第7期14卷 724-727页

作者： Ying Jie SUN Jian Ya lING peng l Han Xing ZHANG Chang Kai ZHANG State Key laboratory of Microbial Technology Life Science School of Shandong UniversityJinan 250100

A simple, rapid and low-cost method of determination for cordycepin in Cordyceps kyushuensis by capillary zone electrophoresis (CZE) was developed. Based on the finding that there is a high concentration of cordycepin in both natural and cultured Cordyceps kyushuensis, the in vitro antitumor activity of cordycepin and the water extracts of Cordyceps kyushuensis has been investigated. This is the first report about the antitumor effect of Cordyceps kyushuensis.

关键词： Cordycepin Cordyceps kyushuensis capillary zone electrophoresis cancer cell line antitumor activity.

Evaluation of the virulence of entomopathogenic fungus, Isaria fumosorosea isolates against subterranean termites Coptotermes spp.(Isoptera:Rhinotermitidae)

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Journal of Forestry Research 2019年第1期30卷 213-218页

作者： J.J.Jessica T.l.peng A.S.Sajap S.H.lee S.A.Syazwan Department of Forest Management Faculty of ForestryUniversiti Putra Malaysia (UPM) Faculty of Veterinary Medicine University Malaysia Kelantan Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia (UPM) Mycology and Pathology laboratory Forest Biodiversity Division Forest Research Institute Malaysia

The entomopathogenic fungus Isaria fumosorosea Wize, formerly known as Paecilomyces fumosoroseus is reported as a promising biocontrol agent for controlling subterranean termites, particularly those belonging to the family Rhinotermitidae. In Malaysia, the family Rhinotermitidae includes two species of subterranean termites with extremely high economic importance; namely Coptotermes curvignathus Holmgren, and the Asian Slubterranean Termite (Coptotermes gestroi Wasmann). To comprehend the potential control of this soil-dwelling fungus against these subterranean termites in Malaysia, an investigation was carried out by testing the pathogenecity of 11 isolates against these termite species. All isolates showed pathogenic potential against the termite (Mortality rate of C. curvignathus:84.4%; C. gestroi:67.3%). IsolatePF49 was the most effective against both species of termites and was further tested for its virulence and *** lC_(50) values of PF49 against C. curvignathus and *** were 7.55×103 and 1.09×102 conidia/ml,respectively. The average number of days required to complete the mycosis process in C. curvignathus and *** were 4.7 and 8 days, respectively. These fungi are believed useful for protecting living trees, plants, wood,wood structures, and other cellulosic materials susceptible to termite infestation and damage.

关键词： Biological control Entomopathogenic fungus Subterranean termites lethal concentration

Blue photoluminescence from nanocrystalline porous silicon structure fabricated by high-current pulsed electron beam irradiation

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Chinese Science Bulletin 2014年第34期59卷 4758-4762页

作者： peng l Xiao-Tong Wang Sheng-Zhi Yang Yan li Xiu-li Hou Qing-Feng Guan School of Materials Science and Engineering Jiangsu University

N-type Si(111) wafers have been processed by high-current pulsed electron beam(HCPEB) treatment with an increasing number of irradiation(1, 10 and 20pulses). The results of this work show that a highly porous nanostructure was formed after irradiation. Moreover, the high-density Si nanocrystals(Si-ncs) about 3 nm were distributed on the surface of Si wafers and exhibited3.02 e V Photoluminescence(Pl) emission in blue *** Pl intensity increases with the increase in the Si-ncs' density in accordance with the quantum confinement model, which can be ascribed to the different pulse time of HCPEB treatment. The possible formation mechanisms of micropores and Si-ncs are discussed.

关键词：纳米多孔硅电流脉冲纳米结构光致发光电子束辐照 Si(111) HCPEB 制作

The Growth Paths and Mechanisms of Chinese Private Enterprise

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Social Sciences in China 2021年第2期42卷 83-102页

作者： Gong Huayan School of Sociology and Population Studies Renmin University of China Institute of Sociology Chinese Academy of Social Sciences 不详

During the past forty years of reform and opening up,China’s private economy has made remarkable *** paper introduces start-up organizational processes into the study of elite mobility in emerging markets,exploring the relationship between the social origins of entrepreneurs and their entrepreneurial *** research finds that the initial scale,growth rate and current size of enterprises established by elite entrepreneurs are larger than those of grassroots *** the deepening of economic reform and the growth of the private economy,the social origins of large business owners generally tend to be elitist and the scale advantage of the enterprises set up by elite entrepreneurs,especially endogenous or inside-track entrepreneurs,is ever more *** expansion of such enterprises’superior position is mainly due to their initial advantages of scale;after the start-up period,the advantage conferred by their pace of growth does not increase *** order to promote the further development of the private economy and release its innovative potential,it is necessary to give full play to the government’s function of regulating market operations and correcting market failure,and thus actively creating a good business environment.

关键词： entrepreneurs enterprise growth enterprise scale market transition

Recent progresses in application of functionalized graphene sheets

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Science China(Technological Sciences) 2010年第9期53卷 2311-2319页

作者： lü peng,FENG YiYu,ZHANG XueQuan,lI Yu & FENG Wei School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China 1. School of Materials Science and Engineering Tianjin University Tianjin 300072 China

Graphene,a rapidly rising star on the horizon of material science,has a unique two-dimensional nanostructure as well as exceptional mechanical and electronic *** its short history,graphene has exhibited great potential in various *** order to implement the potential applications,functionalization of graphene is necessary to obtain uniform dispersions for good *** kinds are dominant for functionalization such as covalent and non-covalent *** former is based on the formation of covalent bonds,and the latter the interaction among *** this review,we summarized briefly the recent progress of functionalized graphene sheets (FGs) in different fields,such as optoelectronic materials,sensors,energy storage materials,catalytic,reinforcing components and so on,and also prospected the development trend of FGs in the future.

关键词： functionalized graphene sheets optoelectronic materials sensors energy storage materials catalytic fields

Responses of arbuscular mycorrhizal fungi to N and P fertilization under different water conditions in a dryland maize agroecosystem

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Responses of arbuscular mycorrhizal fungi to N and P fertili...

Effect of salt-assisted reduction method on morphologies and size of metallic tungsten particles

中国菌物学会第七届全国会员代表大会暨2017年学术年会

作者： peng-peng lü Yong Zheng liang-Dong Guo State Key laboratory of Mycology Institute of Microbiology Chinese Academy of Sciences College of life Sciences University of Chinese Academy of Sciences

Water and nutrition availabilities are crucial factors in maize industry. Arbuscular mycorrhizal（AM） fungi form symbiotic associations with plant roots, playing a key role in enhancing host plant mineral nutrition and water acquisition, improving plant growth and resistant capacity to environmental stresses. Here, four fertilization treatments, including control（Ctrl）, nitrogen addition（N）, phosphorus addition（P）, and nitrogen plus phosphorus addition（NP） under two different water conditions（well-watered vs. water stressed） were established in State Field Research Station of Desert Ecosystem in Fukang, Xinjiang, China. Maize roots and rhizosphere soils of three profile depths（i.e.,0–20, 20–40 and 40–60 cm） were collected to investigate the impact of fertilization and water availability on AM fungal abundance, diversity and community composition. The results showed that N addition trend to decrease extra-radical hyphal（ERH） density and root colonization rate under well watered condition, but not under drought condition. Phosphorus addition trend to increase root colonization rate only under water stressed fields. We identified 64 AM fungal operational taxonomic units（OTUs） belonging to eight families through Illumina Miseq sequencing of fungal SSU r DNA fragment. Higher AM fungal richness was observed in soil than that in root, and no significant N or P addition effect was observed on richness and Shannon index of both root and soil. The AM fungal community composition was significantly different between root and soil. Furthermore, we found that AM fungal community composition was significantly impacted by N and P addition in top 0-20 cm soil under well-watered condition, yet there was no significant difference detected among the fertilization treatments in root regardless of water conditions. Our results highlighted the importance of water and fertilization management on maintaining AM fungal community in maize agroecosystem of the dryland region.

关键词： arbuscular mycorrhizal fungi maize(Zea mays) fertilization Illumina MiSeq diversity community composition

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Transactions of Nonferrous Metals Society of China 2020年第11期30卷 3133-3146页

作者： Ze-peng lü Kai-liang JIAN Jie DANG College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key laboratory of Vanadium−Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China

A simple method was proposed to produce tungsten(W)particles with controllable shape and size by employing the salt-assisted hydrogen reduction.W particles with controlled shape and size were prepared by adjusting the amount of chlorine salts and the *** adding salt additives,the dispersibility of final particles was obviously improved and more adequate growth of particles was *** was found that the effect of NaCl and liCl is particularly *** average sizes of the obtained W particles at 1038 K after adding 0.1 wt.%NaCl and 0.1 wt.%liCl were 0.924 and 1.128μm,*** the increase of temperature and amount of chlorine salts,the dispersity of the produced W particles became much better,the size of W sub-particles was increased,and the shape of W sub-particles was changed from spherical to *** 1349 K,the addition of chlorine salts even multiplied the particle size,and the average sizes of W particles with 1 wt.%NaCl and 1 wt.%liCl were raised up to 21.367 and 29.665μm,*** on the conventional pseudomorphic transformation and chemical vapor transport mechanisms,the effects of adding salts on the reaction mechanism were investigated in detail as well.

关键词： tungsten particles salt-assisted hydrogen reduction chlorine salt morphology size controllable synthesis