排序方式： 共有94条查询结果，搜索用时 15 毫秒
31.
32.
1Generalsituationofthecascades1.1Cascadeshydropowerplants HanjiangRiverisoneofthelongesttributariesof YangtseRiver,originatingfromNingqiangcountyof ShaanxiprovinceandflowingthroughShaanxi provinceandHubeiprovince.HanjiangRiveris1567kmlongintotal,and709kmofitinShaanXi provincerunsthroughHanzhongandAnkangregions fromtheeasttothewest.TheupperreachesofHanjiangfromYangxian countytoBaihecountyinShaanxiprovinceis443km long,anditstotalheadfallsisabout280mhigh.Withabundantwaterpowerresources,its… 相似文献
33.
Interactions of pyrogallol red with proteins and the determination of proteins by resonance light-scattering 总被引：2，自引：0，他引：2
Hu Xiaoli female years old instructor. * Supported by the National Natural Science Foundation of China 《西南师范大学学报(自然科学版)》1998,(5)
Ｉｔｉｓｖｅｒｙｉｍｐｏｒｔａｎｔｔｈａｔｔｈｅｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｒｏｔｅｉｎｃｏｎｃｅｎｔｒａｔｉｏｎｓｉｎｃｌｉｎｉｃａｌｔｅｓｔｓａｎｄｌａｂｏｒａｔｏｒｙｐｒａｃｔｉｃｅ．Ｕｐｔｏｎｏｗ，ｔｈｅｒｅｈａｖｅｂｅｅｎｍａｎｙｍｅ... 相似文献
34.
LI Bo * Department of Applied Mathematics Beijing Institute of Technology Beijing China 《系统科学与系统工程学报(英文版)》1999,(3)
１ ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｔｈｏｕｇｈｍａｎｙｎｏｎｌｉｎｅａｒｐｒｏｇｒａｍｍｉｎｇａｌｇｏｒｉｔｈｍｓｗｉｌｌｏｂｔａｉｎａｌｏｃａｌｓｏｌｕｔｉｏｎｆｏｒａｎｏｐｔｉｍｉｚａｔｉｏｎｐｒｏｂｌｅｍ，ｔｈｅｍａｉｎｄｉｆｆｉｃｕｌｔｙｗｉｔｈｔｈｅｓｅｍｅｔｈｏｄｓｉｓｔｈａｔｔｈｅｌｏｃａｌｍｉｎｉｍａｗｈｉｃｈｔｈｅｙｏｂｔａｉｎｍｉｇｈｔｎｏｔｂｅｇｌｏｂａｌ．Ａｃｔｉｖｅｒｅｓｅａｒｃｈｄｕｒｉｎｇｔｈｅｐａｓｔｔｈｒｅｅｄｅｃａｄｅｓｈａｓｐｒｏｄｕｃｅｄａｖａｒｉｅｔｙ… 相似文献
35.
LIU Zhenrong 《系统科学与复杂性》1992,(4)
In this paper a mathematical model of chemical systems is investigated.We present the conditions for the existence and local stability of the steady statesand the periodic solution of the Hopf type.Specifically,we show by using an ana-lytical method that there may exist two or four Hopf bifurcation points separatedat a finite distance from each other;at the same time,a technique for studying theHopf bifurcation value is given. 相似文献
36.
Foracertainionosphericregion,duetomanyfactorsespeciallytheinvisiblesolarradiation,thechangelawofthetotalelectroncontent(TEC)isdifferentindaytimeandnighttime.ThecorrespondingmathematicalexpressionsofTECshouldalsobedifferent.Therefore,whenusingGPStomodelpreciseionosphericdelay,oneofthecriticalfactorsistoexactlydistinguishtheionosphericdaytimeandnighttimeandreasonablydescribetheTECchangecharacteristicsofthedifferentperiodsattheionosphericpiercepoint(IPP).Inthepast,inthefieldsofGPSresearcha… 相似文献
37.
Gastric vagal afferent inputs reach the glycemia-sensitive neurons of lateral hypothalamic area in the rat 总被引：1，自引：0，他引：1
ZHANG Yueping* ZHU Jingning* JIANG Jianming & WANG Jianjun Department of Biological Science Technology Nanjing University Nanjing China * These two authors made equal contributions to this work. 《科学通报(英文版)》2003,48(6)
The lateral hypothalamic area (LHA) is one of the most important central areas in the regulation of feeding behavior[1]. The glycemia-sensitive neurons within the LHA sense the blood glucose level and subsequently trig-ger various visceral and somatic responses for maintaining the homeostasis of blood glucose concentration. Some electrophysiological studies have demonstrated that the gastric vagal afferent inputs could reach the LHA in the cat[2,3], but the studies did not reveal whether th… 相似文献
38.
以铁酸四丁醋、石肖酸铁、石肖酸铬为原料,采用改进的溶胶一凝胶法制备铁一铬共掺杂的二氧化铁纳米球对该纳米球进行了结晶结构、形貌和光吸收性质方面的表征,测试了该纳米球在紫外一可见光照射下光催化产氢活性结果表明,在掺杂总量不变的情况下,铁一铬共掺杂二氧化铁纳米球获得最好的光催化活性(133.6 umol/(g.h)),并且具有优秀的光催化稳定性. 相似文献
39.
C12 H4 ,C18H6,C2 4 H8大环多炔化合物是以乙炔为基本单元 ,以乙烯为连接元构成 .利用量子化学PM 3方法进行分子构型的优化和频率分析 ,判断分子的稳定性 相似文献
40.
对２,３－二氯－６－羧酰氯喹啉类活性染料的反应活泼性以及“染料－纤维”键的稳定性进行了反应动力学研究,测定水解速度常数;与其他类型活性染料进行比较,对此类活性染料性能进行了评价。 相似文献