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Analysis of the heat transfer in unsymmetrically heated triangular microchannels in slip flow regime

Science China(Technological Sciences) 2004年第4期47卷 436-446页

作者： ZHU xun liao Qiang XIN Mingdao Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China Institute of Engineering Thermophysics Chongqing University Chongqing 400044 China

A theoretical analysis of heat transfer characteristics is presented for the fully developed laminar flow of the incompressible gas in the triangular microchannels heated unsymmetrically with constant axial heat flux. Through solving the energy equation with temperature jump boundary conditions in slip flow regime by virtue of a computation- oriented method of the orthonormal function analysis, the dimensionless temperature profiles and the average Nusselt number for various thermal boundary conditions are obtained. The effects of Knudsen number, aspect ratio, and thermal boundary conditions on the heat transfer are discussed. The calculated results show that the orthonormal function method can be used to study the heat transfer characteristics of the unsymmetrically heated triangular microchannels. The average Nusselt number in triangular microchannels is lower for slip flow than for no-slip flow, and decreases with increasing Knudsen number. The aspect ratios and thermal boundary conditions of triangular microchannels have significant influences on the change of average Nusselt numbers with the increase in the Knudsen number. For the equilateral triangular microchannels, the decrease of the Nusselt number ratio due to temperature jump is smaller at large Knudsen number and larger at small Knudsen number on the boundary condition of bottom wall heated alone as compared with the one on the boundary condition of two heated hypotenuse walls. The correlations of the average Nusselt number with the Knudsen number for equilateral triangular microchannels are obtained.

关键词： slip flow regime, triangular microchannel, unsymmetrical thermal boundary, heat transfer.

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Methods to determine stress profile in ALT based on theoretical life models

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Chinese Journal of Aeronautics 2015年第3期28卷 729-736页

作者： Chen Yunxia Jing Hailong liao xun Kang Rui School of Reliability and Systems Engineering Beihang University

Abstract With the recent products being more reliable, engineers cannot obtain enough failure or degradation information through the design period and even the product lifetime, therefore, accel erated life test （ALT） ihas become the most popular way to quantify the life characteristics of prod ucts. Test design is the most essential topic, such as testing duration, stress profile, data inference, etc. In this paper, a method and procedure based on theoretical life models is proposed to determine the accelerated stress profile. Firstly, the method for theoretical life calculation is put forward based on the main failure mechanism analysis and the theoretical life models. Secondly, the method is pro vided to determine the accelerated stress profile, including the method to determine the accelerated stress types and the stress range on the basis of the main failure mechanism analysis, the method to determine the acceleration factor and the accelerated stress level based on life quantitative calcula tion models, and the collaborative analysis method of the accelerated test time while taking the mul tiple failure mechanisms into consideration. Lastly, the actuator is taken as an example to describe the procedure of the method and the engineering applicability and the validity are verified.

关键词： Acceleration factor Accelerated stress profileALT Failure mechanisms Main failure mechanismanalysis Theoretical life models

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Current susceptibilities of brown planthopper Nilaparvata lugens to triflumezopyrim and other frequently used insecticides in China

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Insect Science 2021年第1期28卷 115-126页

作者： xun liao Peng-Fei Xu Pei-Pan Gong Hu Wan Jian-Hong Li nstitute of Crop Protection Guizhou UniversityGuiyangChina Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina

The brown planthopper is a notorious rice pest in many areas of *** evolution of insecticide resistance in Nilaparvata lugens has become a serious problem in the effective control of this pest in the paddy *** this article,the current susceptibility of *** field populations to novel mesoionic insecticide triflumezopyrim and major classes of chemical insecticides was determined and *** monitoring results indicated that field populations of *** had developed low resistance to triflumezopyrim(resistance ratio,RR:1.3-7.3-fold)during 2015-2018 in China,and the median lethal concentration values varied from 0.05 to 0.29 mg/***,during 2017 to 2018,field populations of *** showed high resistance levels to thiamethoxam(RR:456.1-1025.6-fold),imidacloprid(RR:2195.3-6899.0-fold)and buprofezin(RR:1241.57521.7-fold),moderate to high resistance levels to dinotefuran(RR:97.6-320.1-fold),clothianidin(RR:69.4-230.1-fold)and isoprocarb(RR:44.1-108.0-fold),and low to moderate levels of resistance to chlorpyrifos(RR:12.0-29.7-fold)and nitenpyram(RR:6.9-24.1-fold).In contrast,*** just showed low resistance to sulfoxaflor(RR:3.3-8.5-fold)and etofenprox(RR:5.0-9.1-fold)in the ***,the P450 gene CYP6ER1 was found to be significantly overexpressed in all five field populations of *** collected in 2018 when compared with a laboratory susceptible *** findings will provide useful information to delay the evolution of insecticide resistance in ***.

关键词： Nilaparvata lugens(Stal) P450 gene susceptibility triflumezopyrim

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Two New Sesquiterpenoid Glucosides from the Aerial Parts of Saussurea involucrate

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Journal of Integrative Plant Biology 2007年第5期49卷 609-614页

作者： Xlao-Ling Wang Suo-Lang Gesang Wei Jiao xun liao Li-Sheng Ding Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 China Institute of National Medicine Southwest University for Nationalities Chengdu 610041 China Tibet Autonomous Region Institute for Drug Control Lasa 850000 China

Two new sesqulterpenoid glucosides, namely α-hydroxycostic acid 6-β-D-glucopyranoside （compound 1） and 11 βH-11,13-dlhydrodehydrocostuslactone 8α-O-（6＇-acetyl）-β-D-glucopyranoside （compound 2）, along with 11 known sesqulterpenoids （compounds 3-13） were isolated from the aerial parts of Saussurea involucrate （Kar. et Kir.） Sch.- BIp. The structures of the new sesquiterpenoid glucosides were established by one- and two-dimensional nuclear magnetic resonance and mass spectrometry analysis.

关键词： 6α-hydroxycostic acid 6-β-D-glucoside 11 βH-11,13-dihydrodehydrocostuslactone 8α-O-(6'-acetyl)- α-D-glucoside Saussureainvolucrate sesquiterpenoid glucoside.

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Selective extraction of flavonoids from Ginkgo biloba leaves using human serum albumin functionalized magnetic nanoparticles

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Chinese Chemical Letters 2013年第12期24卷 1099-1102页

作者： Xiao-Yun Ren Ying Xue Jian Liang Li-Sheng Ding xun liao Chengdu Institute of Biology Chinese Academy of Sciences

In a novel procedure, human serum albumin timctionalized magnetic nanoparticles （ HSA-MNPS ） were used to selectively extract nine flavonoids in the extract of Ginkgo biloba leaves. The chemical structures of those flavonoids were characterized with high performance liquid chromatography coupled with mass spectrometry （HPLC-MS）. The selective extraction with HSA-MNPs coupled with structural elucidation with HPLC-MS shows powerful potential for analysis of bioactive components in traditional Chinese medicines.

关键词： Ginkgo biloba Flavonoids HSA-MNPs High performance liquid chromatography Mass spectrometry

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Monoterpene Glycosides from the Roots of Paeonia lactiflora

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Chinese Chemical Letters 2006年第7期17卷 916-918页

作者： Xiao Ling WANG Wei JIAO xun liao Shu Ling PENG Li Sheng DING Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 Institute of National Medicine Southwest University for Nationalities Chengdu 610041

A new monoterpene glycoside, together with nine known ones, 3-O-methylpaeoniflorin, mudanpioside J, paeoniflorin, benzoylpaeoniflorin, oxypaeoniflorin, benzoyloxypaeoniflorin, oxybenzoylpaeoniflorin, albiflorin and lactiflorin, was isolated from the roots of Paeonia lactiflora Pall.. The structure of the new compound was elucidated as galloylalbiflorin by the spectro- scopic evidence including ESI-MS, 1D- and 2D-NMR spectra.

关键词： Paeonia lactiflora Paeoniaceae monoterpene glycoside galloylalbiflorin.

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A Novel Monoterpene Glycoside from Swertia mileensis

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Chinese Chemical Letters 2003年第11期14卷 1154-1155页

作者： Ying Tong DI xun liao Shu Lin PENG Jian LIANG Li Sheng DING Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041

A novel monoterpene glycoside, mileenside, was isolated from Swertia mileensis by repeated normal and reverse phase silica gel chromatography and its structure was elucidated mainly based on spectral evidence.

关键词： Swertia mileensis Gentianaceae monoterpene glycoside mileenside.

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Panthogenins A and B,two novel norergostanol steroids from Dioscorea panthaica

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Chinese Chemical Letters 2014年第9期25卷 1256-1258页

作者： Xiao-Qing Shan Shu-Lin Peng Hai-Li Shi Xiao-Ling Wang Li-Sheng Ding xun liao Chengdu Institute of Biology Chinese Academy of Sciences Ethnic Pharmaceutical Institute Southwest University for Nationalities

Two novel 27-norergostanol steroids, panthogenins A （1） and B （2）, possessing unusual rings E and F featuring a ketal moiety at C-25 were isolated from rhizomes ofDioscorea panthaica. Their structures and relative configurations were elucidated by extensive spectroscopic methods including 1D and 2D NMR techniques, and the structure of panthogenin A was further confirmed by X-ray crystallography. Both compounds showed potent in vitro insulin sensitizing activity.

关键词： Dioscorea panthaica Dioscoreaceae Norergostanol steroids Structural elucidation Insulin sensitizing activity

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An MFC capable of regenerating the cathodic electron acceptor under sunlight

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Science China(Technological Sciences) 2010年第9期53卷 2489-2494页

作者： FU Qian,LI Jun,ZHU xun,liao Qiang,YE DingDing & ZHANG Liang Institute of Engineering Thermophysics,Chongqing University,Chongqing 400030,China 1. Institute of Engineering Thermophysics Chongqing University Chongqing 400030 China

A renewable MFC (microbial fuel cell) cathode was used in this study because the iodide ion could react with oxygen to generate triiodide under natural *** feasibility of the regeneration of triiodide ion under natural sunlight and the effect of the regenerated triiodide ion concentration on the MFC performance were *** results showed that the power density of the MFC using triiodide ion as cathodic electron acceptor was significantly higher than that of using ferricyanate,and that the iodide ion can be oxidized to triiodide ion by oxygen in air at the expense of natural *** addition,it was obvious from the experimental results that the MFC performance was improved with the increase of the triiodide concentration,indicating that the concentration of triiodide ion had a critical effect on the MFC *** linear sweep voltammetry (LSV) curves for the electro-reduction of triiodide ion on the carbon paper were obtained and the results suggested that the diffusion process of triiodide ions to cathode was the control factor for the MFC performance.

关键词： microbial fuel cell cathodic electron acceptor triiodide ion

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A Novel Pregnane Glycoside from Biondia chinensis

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Chinese Chemical Letters 2003年第10期14卷 1027-1028页

作者： Xing Gen TAN, Shu Lin PENG, xun liao, Jian LIANG, Li Sheng DING Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041 Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041

A novel pregnane glycoside, biondianoside E, was isolated from the roots of Biondia chinensis. By the spectroscopic and chemical methods, this structure was elucidated as 3B, 5B, 14B, 205, 21-pentahydroxypregnane 3-O-... 详细信息

关键词： Biondia chinensis pregnane glycoside biondianoside E.

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