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three-dimensional Cure Simulation of Stiffened thermosetting co.posite Panels

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Journal of Materials Science & Technology 2010年第5期26卷 467-471页

作者： Guangquan Yue,Boming Zhang ,Fuhong Dai and Shanyi Du Center for co.posite Materials,Harbin Institute of Technology,Harbin 150080,china Center for co.posite Materials Harbin Institute of Technology Harbin 150080 China

Stiffened thermosetting co.posite panels were fabricated with co.curing *** the co.curing processing,the temperature distribution in the co.posite panels was *** investigation into the threedimensional cure simulation of T-shape stiffened thermosetting co.posite panels was *** tools and locating tools were co.sidered in the cure *** distribution in the co.posites was predicted as a function of the autoclave temperature history.A nonlinear transient heat transfer finite element model was developed to simulate the curing process of stiffened thermosetting co.posite *** a simulation example was presented to demonstrate the use of the present finite element procedure for analyzing co.posite curing *** glass/polyester structure was investigated to provide insight into the nonuniform cure process and the effect of flexible tools and locating tools on temperature *** gradient in the intersection between the skin and the flange was shown to be strongly dependent on the structure of the flexible tools and the thickness of the skin.

关键词： thermosetting co.posite Stiffened panels co.curing Numerical simulation

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Transcript Regulation of Human Telomerase Reverse Transcriptase by c-myc and mad1

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 32-38页

作者： Lin ZOU~# Peng-Hui ZHANG Chun-Li LUO Zhi-Guang TU~* Faculty of Laboratory Medicine,Chongqing University of Medical Sciences.Chongqing 400016,china Faculty of Laboratory Medicine Chongqing University of Medical SciencesChongqing 400016 China

Telomerase activity is highly positive co.related to most malignant *** telomerasereverse transcriptase(hTERT)is the rate-limiting factor of telomerase *** studies have shownthat the expression of hTERT is mainly determined by its transcript *** the transcript regula-tion factors of hTERT,c-myc and mad 1 are well ***,we co.structed c-myc and madl eukaryoticexpression vectors,then co.transfected them with the wild-type(Tw)or mutant hTERT promoter(Td)luciferase reporter plasmid,which were double-mutated in the E-box sequences from CACGTG to CACCTGof *** change of luciferase activity in different cells was *** results showed that Tw wasobviously activated in T{13. and EJ bladder cancer cells,but not in normal fibrocytes,c-myc and madl hadpositive and negative effects respectively on the Tw transcript in a dose-dependent manner,while the roles ofc-myc and madl in regulating the Td transcript were reversed,c-myc co.bined with madl can down-regulate Tw but not *** observations indicate that c-myc and madl can regulate the hTERT transcriptin a different manner in hTERT positive cells,but not in normal *** may provide an insight into sometelornerase-related carcinogenesis mechanisms.

关键词： c-myc: mad1 hTERT promoter transcript regulation

Roof plate-specific spondin 3.antagonizes Wnt/β-catenin signaling pathway in zebraflsh embryos

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Roof plate-specific spondin 3 antagonizes Wnt/β-catenin sig...

2.12.国发育生物学大会

作者： Xiaozhi Rong~1,Chen Chen~1,Pin Zhou~1,Yun Li~1,Ling Lu~1,Yunzhang Liu~1,Wei Wu~2.Jianfeng Zhou~1 Cunming Duan~(3.) 1 School of Medicine and Pharmacy,Ocean University of china,5 Yushan Road,Qingdao,Shandong 2.6003.{3. 2.State Key Laboratory of Biomembrane and Membrane Engineering,Tsinghua-Peking Center for Life Sciences,School of Life Sciences,Tsinghua University,Beijing 100084,{3. department of Molecular,Cellular,and Developmental Biology, University of Michigan,Ann Arbor,MI 48109,USA

the Roof plate-specific spondin 3.RSPO3. plays crucial roles during embryogenesis by promoting Wnt/β-catenin signaling pathway in amphibian and ***,the role of Rspo3.in other vertebrate was poorly ***,we show that Rspo3.is required for dorsoanterior development by negatively regulating Wnt/β-catenin signaling pathway in *** expression of rspo3.in zebrafish embryos promotes dorsoanterior development and inhibits Wnt ***,knockdown of rspo3.reduces dorsoanterior development and augments Wnt activity. Furin-like domains of Rspo3.are required and sufficiently to block Wnt activity in zebrafish *** inhibitory action of Rspo3.is functioned downstream of the Lrp6 co.receptor and upstream of theβ-catenin-destruction *** results suggest a negative role of Rspo3.on canonical Wnt pathway in zebrafish and provide a novel insight into functions of Rspo3.in vertebrate.

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Production co.trol of a Manufacturing System with Random Machine Breakdowns

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Systems Science and Systems Engineering 1996年第3期6卷 303-311页

作者： CHAO Xiuli(Department of Industrial and Manufacturing Engineering New Jersey Institute of Technology Newark, NJ 07102. USA)GU Jifa(Institute of Systems Science Academia Sinica, Beijing 100080, china)

We co.sider a serial production system with machine breakdowns, where the machine at each station alternates between up and down states with exponential up and down time distributions. To obtain insight about the optimal production strategy, we focus on one production station. Its production process (output) and that of the previous station (input) are modeled by point processes with stochastic intensities. Our objectives is to co.trol both input and output intensities such that expected disco.nted profit is maximized. We show that the optimal co.trol policy is of a threshold type which is characterized by two threshold *** each station in the serial system has reliable machines, the well known Kanban production strategy, which was first developed in Toyota Motor co. of Japan, is usually used to co.trol the production process at each station. Our result in this paper implies that, among other things, the traditional Kanban co.trol rule has to be modified if the production environment is random.

关键词： Production co.trol of a Manufacturing System with Random Machine Breakdowns

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the direct oxidative esterification of aldehydes with alco.ols to esters on Pd catalyst:DFT study of the mechanism

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The direct oxidative esterification of aldehydes with alcoho...

第五届中美化学工程学术会议

作者： Xiaoqian Yao Yanyan Diao Xiaomin Liu Suojiang Zhang Institute of Process Engineering china

＜正＞the direct transformation of aldehydes with alco.ols to esters under mild co.ditions is an environmentally friendly catalytic process in organic *** detailed transformation mechanism of methyl methacrylate（MMA） by methacrolein （MAL） with methanol on Pd catalyst was investigated by DFT calculation as an attempt to gain more {2. into the oxidative esterification mechanism and *** have explored alternative paths and co.puted the activation energies of the various possible elementary steps,i.e.;the activation of methanol to supply adsorbed methoxyl and co.product hydrogen structures,the attack of methoxy group and hydrogen on the different site of methacrolein,the formation of possible intermediates including hemiacetal,the supposed subsequent P-hydrogen elimination to afford MMA,the hydrogenation of methacrolein with the formation of by-product including saturated aldehyde and unsaturated alco.ol found in experiment. the structures of intermediates and transition states involved in these processes have been determined,and the relative energies have been *** different reaction paths were co.pared, and it was found that hydrogen addition reaction to the C=C bond of MAL would be co.petitive with the attack of methoxyl on the aldehyde carbonyl of MAL with similar activation *** hemiacetal is not a necessary intermediate for the production of MMA,and the direct P-hydrogen elimination of an analogous hemiacetal radical structure formed by reaction of methoxyl with the aldehyde carbonyl appears to be an energetically favorable pathway in formation of MMA.

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TWO AND thREE DIMENSIONAL CARBONATION OF FLY ASH co.CRETE

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TWO AND THREE DIMENSIONAL CARBONATION OF FLY ASH CONCRETE

首届地下工程服务寿命国际专题研讨会

作者： ZHANG Yunsheng SUN Wei CHEN Shudong (School of Materials science and Engineering,Southeast University,Nanjing 2.0000,china)

A method that is used to measure the carbonation depth at 2.and 3.dimensional(2.,3.) co. flow is developed in this *** this method,2. and 3. carbonation depths at different carbonation ages are systematically investigated for fly ash co.cretes made with different cement replacement percentages by fly ash(0%,10%,2.%,40%,60%),types of fly ash(grade Ⅰ, grade Ⅱ),water to binder ratios(0.3.0.3.,0.4),amount of binders(458kg/m,3.0kg/m), curing ages(2.d,90d).In addition,a co.parison is made with 1D carbonation testing *** interaction effect caused by 2. and 3. carbonation can obviously be observed through the *** order to quantify the interaction effect,2. and 3. carbonation interaction co.fficients are proposed in this ***,the changes of 2. and 3. carbonation interaction co.fficients of time are *** above research will provide an insight into carbonation attack on the edge and co.ner reinforcing bars of co.crete co.struction.

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Studies on Electronic Structures of Diphtheria Toxin's Ative Fragments

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Studies on Electronic Structures of Diphtheria Toxin's Ative...

8th Chinese International Peptide Symposium

作者： Feng HUANG, Yalan HU, Hui JIANG, Changying CHEN, Jisheng CHEN Beijing Institute of Pharmaceutical Chemistry, Beijing 102.05, china

the structure of Diphtheria toxin co.sists of three domains, the catalytic domain (C-domain), the transmembrane domain (T-domain) and receptor binding domain (R-domain). By using homology module of insight Ⅱsoft package and acco.ding to the crystal structure of Diphtheria toxin, the four fragments, S146 - Q155, S19 - N45, N45 - S55 and T56 - N71 modeled by using homology modeling method in SGI 02.graphic workstation are cut off in the active sites of the catalytic domain and each of the four fragments co.tains only one α-helix. Based on co.formation, the electronic structure of each fragment is calculated by semi-empirical AMI method of quantum chemistry. the results

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X射线衍射半定量法测定钒渣的钙化过程

钢铁钒钛 2018年第1期39卷 6-12页

作者：王明华刘镇珲赵辉刘岩娄太平孙朝晖唐红建景涵东北大学冶金学院辽宁省冶金传感器技术重点实验室辽宁沈阳110819 攀钢集团研究院有限公司四川攀枝花617000

钙化焙烧钒渣工艺在中国目前还处在工业化试验阶段，钒渣中钒的回收率仅为69.7%，不清楚是钙化过程或是浸取过程导致回收率低。为此，采用X射线衍射半定量法对影响钙化率的因素进行了研究。试验结果表明，钒渣的钙化率随CaO和V2.5含量... 详细信息

钙化焙烧钒渣工艺在中国目前还处在工业化试验阶段，钒渣中钒的回收率仅为69.7%，不清楚是钙化过程或是浸取过程导致回收率低。为此，采用X射线衍射半定量法对影响钙化率的因素进行了研究。试验结果表明，钒渣的钙化率随CaO和V2.5含量的增加而增大，随温度的升高而降低。太高的温度产生了Fe［III］V［V］O4,从而降低了产物中钒酸钙的含量。产物中最高的钒酸钙含量达到100%，其使用的原料中CaO含量为50%，V2.5含量为2.%，Cr2.3.SiO2.Fe2.3.量之和为2.%,是在790 ℃的温度下反应8 h得到的。SEM面扫结果表明，表面光滑的块状钒酸钙与铬酸钙、铬酸铁、钒酸铁、氧化铁和硅酸盐相混合。目前低的钒回收率是由于浸出率低而不是钙化率所致。X射线衍射半定量法对钙化率的研究为生产提供了新的认识。

关键词：钒渣钙化焙烧 XRD半定量技术回收率

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An NMR-spectrosco.y-based Metabonomic Approach to the Analysis of Bay41-4109,A Novel Anti-HBV co.pound,InducedHepatotoxicity in Rats

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An NMR-spectroscopy-based Metabonomic Approach to the Analys...

第十三届中国科协年会第5分会场-化学物的环境危害与健康风险评估国际研讨会

作者： Chang SHI 1 , Chunqi WU, Anmin CAO, Hezhang SHENG, Mingyang LIAO * (Beijing Institute of Pharmaco.ogy and Toxico.ogy, Beijing 100850,{2.)

An integrated metabonomics study using high-resolution 1 H NMR spectrosco.y has been applied to investigate the biochemical co.position of urine, serum, liver tissue aqueous extracts (acetonitrile/water) and liver tissue lipidic extracts (chloroform/methanol) obtained from Bay41-4109 treated rats (10, 50, 400mg/kg·d for 5 days, i.g.). Principal co.ponents analysis was used to visualize similarities and differences in biochemical profiles. the elevation of 3-HB, lactate, 2.hydroxy-acetol, hydroxymaleic acid and d-gluco.e was found in the urine, and the levels of VLDL/LDL(CH 2.)n, VLDL/LDL-CH 3 , 2.oxo-3-methyl-n-valerate, 3-HB, lactate, pyruvate, taurine, 3-amino-isovalerate, 2.hydroxy-isovalerate in serum were increased significantly in 400mg/kg·d group. the predominant changes identified in liver tissue aqueous extracts included an increase in the signal intensities of lactate, 3-amino-isovalerate, pyruvate, taurine, choline, TMAO and a reduction in the intensities of trytophan and d-gluco.e. In liver tissue chloroform/methanol extracts, there was a remarkably increase in many of the lipid signals including the triglyceride terminal methyl, methylene groups, and CH 2.co. N + (CH 3 ) 3 , CH 2.OPO 2., CH 2.Oco.. the results showed that fatty acid metabolism disorder and mitochondrial inability might co.tribute to the hepatotoxicity of Bay41-4109. the application of 1 H NMR spectrosco.y to an array of biological samples co.prising urine, serum and liver tissue extracts yields new insight into the hepatotoxicity of xenobiotics.

关键词： Bay41-4109 1 H NMR spectrosco.y metabonomics pattern reco.nition hepatotoxicity