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951.
1 Results Electroactive polymers (EAPs) driven by transducing electric energy into mechanical energy have been the subjects of recent interest[1].“Ionic liquids“,consisting entirely of cation and anion,have characteristic features such as negligible volatility,non-flammability,thermal and chemical stability,and high ionic conductivity.We proposed an EAP actuator utilizing ion-gels[2-3],which consist of ionic liquids and polymers,sandwiching with two carbon material sheets as shown in Fig.1.This electrol... 相似文献
952.
马余刚 《复旦学报(自然科学版)》2007,46(1)
1IntroductionPhase transition and critical phenomenon are extensively debatable subjects in the natural sciences.Re-cently,the same concept was introduced into the astronomical objects[1]as well as the microscopic systems,such as in atomic cluster[2]and n… 相似文献
953.
中朝板块北缘志留纪海岛的发现 总被引:2,自引:0,他引:2
在内蒙古达尔罕茂明安联合旗北部巴特敖包地区发现了志留纪的海岸带及其底栖无脊椎动物化石(层孔虫、日射与床板珊瑚等),证实当时该地发育一个位于中朝古板块北缘大陆棚上的小海岛,将其命名为巴特岛.该岛的基部由奥陶纪火成岩组成,长、短轴分别为610和200m,现今呈北东-南西向延伸.志留纪罗德洛世(距今约420Ma)的地层围绕该岛分布,产状向四周倾状.巴特岛的南缘(背风)发育皮壳状生物,栖息在火成岩顶面并被 相似文献
954.
GAO Zhi-wei Ho Daniel W. C. WANG Xian-lai LI Guang-quan . Tianjin University Tianjin China . City University of Hong Kong Kowloon Hong Kong China 《系统科学与系统工程学报(英文版)》2000,(1)
1 IntroductionConsider a singular decentralized control system of the formEx(t) =Ax(t) ∑Ni=1Biui(t)yi =Cix(t) ,i∈ N ={ 1 ,2 ,… ,N}(1 )where x(t)∈ Rn is the state vector,ui(t)∈ Rmi and yi(t)∈ Rpi are respectively the localcontrol input and measure outputvectors of the ith control channel.The matrix E may besingular,i.e.,rank(E) 相似文献
955.
WANG Dong WANG Qi-wen ZHANG Shi-ying .Guanghua School of Management Peking University Beijing .School of Management Tianjin University Tianjin China 《系统科学与系统工程学报(英文版)》2000,(2)
1 IntroductionAfter10yearsdevelopment,thestockmarketsofchinaarewaitingtoseestock-indexfu-turesinthenewcentury.Itisofgreatimportantforbothsmallinvestorsandlargeinvest-menthousestoadjusttheirbehaviorincasetheyenterintomarketswithnewinstruments.Inrecentyears,speculatingwithfutureswasdiscussedinsomepapers[1~4],andtheresultsachievedroutinelyholdtheassumptionsasnotransactioncosts(TC),nodifferentbetweenborrowingandlandingrates,andalltradingprofitsbeingsubjecttothesametaxrate.Themainproblemisthatne… 相似文献
956.
辣根过氧化物酶处理五氯酚过程的毒性特征 总被引:3,自引:0,他引:3
用酶的催化聚合作用来处理酚类及芳香胺类化合物的污染是近年来受到重视的新方法,但人们很少研究废水在这一处理过程中的毒性变化。采用辣根过氧化物酶和过氧化氢在pH值为4时处理含五氯酚的模拟废水,集中研究了该过程的发光菌毒性特性。结果表明,五氯酚溶液的毒性在处理后大为降低,总毒性可降低至起始毒性的15%左右。处理过程的产物有少量溶解在水中,也构成一部分毒性。 相似文献
957.
纤溶酶原激活因子和抑制因子在早期胎盘中的表达及其功能 总被引:5,自引:1,他引:4
用原位杂交方法研究了人早期胎盘中组织型(t)和尿激酶型(u)纤溶酶原激活因子(PA)与其相应的抑制因子1型(PAI-1)和2型(PAI-2)mRNA的分布。结果表明:(1)在绒毛和蜕膜的血管壁,Rohrs和Nitabuch纹间的蜕膜中的大部分外细胞滋养层细胞沿绒毛盘、基底盘、绒毛叶间隔和绒毛膜的细胞滋养层细胞以及蜕膜的腺体细胞中都检测到tPA、uPA、PAI-1和PAI-2mRNA;(2)在基底绒 相似文献
958.
Shurong LI Chunwang HOU 《系统科学与复杂性》2007,20(1):108-118
In this paper, the collision problem of two moving objects is investigated. The objects are described by two algebraic sets (ellipses or circles in the paper). The collision problem discussed involves both static and dynamic case. The static case is that each object moves with known velocity. We use nonlinear programming to decide whether the objects collide. The dynamic case is that each object is controlled by a constraint external force which can be regulated online. For the dynamic case, the collision problem can be modelled as a Minmax problem which can be solved by using differential games. If collision occurs, the time and place of the first collision are given. The moving trajectories are provided in the paper. 相似文献
959.
Samuel CS Hewitson TD Unemori EN Tang ML 《Cellular and molecular life sciences : CMLS》2007,64(12):1539-1557
The peptide hormone relaxin is emerging as a multi-functional factor in a broad range of target tissues including several
non-reproductive organs, in addition to its historical role as a hormone of pregnancy. This review discusses the evidence
that collectively demonstrates the many diverse and vital roles of relaxin: the homeostatic role of endogenous relaxin in
mammalian pregnancy and ageing; its gender-related effects; the therapeutic effects of relaxin in the treatment of fibrosis,
inflammation, cardioprotection, vasodilation and wound healing (angiogenesis) amongst other pathophysiological conditions,
and its potential mechanism of action. Furthermore, translational issues using experimental models (to humans) and its use
in various clinical trials, are described, each with important lessons for the design of future trials involving relaxin.
The diverse physiological and pathological roles for relaxin have led to the search for its significance in humans and highlight
its potential as a drug of the future.
Received 12 December 2006; received after revision 12 February 2007; accepted 15 March 2007 相似文献
960.
Pyruvate dehydrogenase kinase regulatory mechanisms and inhibition in treating diabetes, heart ischemia, and cancer 总被引:2,自引:2,他引:0
The fraction of pyruvate dehydrogenase complex (PDC) in the active form is reduced by the activities of dedicated PD kinase
isozymes (PDK1, PDK2, PDK3 and PDK4). Via binding to the inner lipoyl domain (L2) of the dihydrolipoyl acetyltransferase (E2
60mer), PDK rapidly access their E2-bound PD substrate. The E2-enhanced activity of the widely distributed PDK2 is limited
by dissociation of ADP from its C-terminal catalytic domain, and this is further slowed by pyruvate binding to the N-terminal
regulatory (R) domain. Via the reverse of the PDC reaction, NADH and acetyl-CoA reductively acetylate lipoyl group of L2,
which binds to the R domain and stimulates PDK2 activity by speeding up ADP dissociation. Activation of PDC by synthetic PDK
inhibitors binding at the pyruvate or lipoyl binding sites decreased damage during heart ischemia and lowered blood glucose
in insulin-resistant animals. PDC activation also triggers apoptosis in cancer cells that selectively convert glucose to lactate.
Received 25 August 2006; received after revision 20 November 2006; accepted 20 December 2006 相似文献