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排序方式: 共有6437条查询结果,搜索用时 15 毫秒
71.
LIU Hui-Min ZHANG Wei XIN Ying ZHANG Wen-Qin② 《结构化学》2004,23(5):532-536
1 INTRODUCTION We are presently involved in the synthesis and photodimerization of the analogues of trans-2-sty- rylbenzoxazole (BOEP), which have been widely reported as fluorescent whiteners and remedies[1]. Some structures of BOEP derivatives and thei… 相似文献
72.
Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in China 总被引:1,自引:0,他引:1
HAN Yanben GUO Zengjian WU Jinbing & MA Lihua . National Astronomical Observatories Chinese Academy of Sciences Beijing China . Earthquake Research Institute of Lanzhou CSB Lanzhou China Correspondence should be addressed to Han Yanben 《中国科学G辑(英文版)》2004,(2)
A big earthquake (Ms = 8.1) occurred at western Kunlun Mts gap on November 14, 2001. It is the biggest earthquake in China in the past 50 years and the only one with a magnitude bigger than 8 in China after Dangxiong Earthquake (M = 8) in Tibet in 1951. The big earthquake has drawn wide attention of scientists in seismological, geophysical, geological and astro-geodynamic circles. Scientists are interested in the occurrence regularity of the very big earthquakes and try to find out the fac… 相似文献
73.
Xinghua Wang 《计算数学(英文版)》2003,(2)
The convergence problem of the family of Euler-Halley methods is considered under the Lipschitz condition with the L-average, and a united convergence theory with its applications is presented. 相似文献
74.
Chen Yongnian 《模糊系统与数学》1995,(1)
ANTIFUZZYVECTORSPACES(Ⅱ)ChenYongnian(DepartmentofMathematics,XinjiangNormalUniversity,830054,Xinjiang,P.R.China)ANTIFUZZYVECT... 相似文献
75.
COMPLETE EIGEN-SOLUTIONS FOR ANTI-PLANE NOTCHES WITH MULTI-MATERIALS BY SUPER-INVERSE ITERATION 总被引:2,自引:0,他引:2
Xu Yongjun Yuan Si 《Acta Mechanica Solida Sinica》1997,10(2):157-166
In this paper,the super-inverse iterative method is proposed to compute the accurateand complete eigen-solutions for anti-plane cracks/notches with multi-materials,arbitrary opening an-gles and various surface conditions.Taking the advantage of the knowledge of the variation forms ofthe eigen-functions,a series of numerical techniques are proposed to simplify the computation andspeed up the convergence rate of the inverse iteration.A number of numerical examples are given todemonstrate the excellent accuracy,efficiency and reliability of the proposed approach. 相似文献
76.
JINJIANG YUAN 《运筹学学报》1998,(3)
1.IntroductionGraphsconsideredinthispaperarefiniteandsimple.FOragraphG,V(G)andE(G)denoteitssetofvenicesandedges,respectively.AbijectionwillbecalledalabellingofG.Letpbeapositiverealnumber.ForagivenlabellingTofagraphG,definethegndiscrepencya.(G,ac)ofTasTheobjectiveoftheminimum-p--sumproblemistofindalabelling7ofagraphGsuchthatac(G,T)isassmallaspossible.ThelabellingTminimizinga.(G,7)iscalledanoptimalHsumlabellingofG.Theminimumvalueiscalledtheminimum-psumofG.ItisshowninI31thattheminimum-… 相似文献
77.
YANG BENFU 《高校应用数学学报(英文版)》1994,9(3):291-297
USINGFINITEGEOMETRIESTOCONSTRUCT3-PBIB(2)DESIGNSAND3-DESIGNS¥YANGBENFU(DepartmentofMathematics,ChengduTeachersCollege,Chengdu... 相似文献
78.
This paper tries to introduce the reader to the method of using photochemical re-action to copy holographic optical elements(HOEs)in relief.The holographic blazing gratingso copied is groove depth adjustable phase modulability enlarged through copying and 3.3times the diffraction efficiency(DE)of the original grating.It is expected that the newmethod will lead to the mass production of the light-weight HOEs at low cost. 相似文献
79.
Li Heng—pei 《大学数学》1993,(1)
<正> In this paper we'll prove a fundameutal property of the vector space by means of the ex-tension field,i.e.the numbers of the elements of a basis of the vector space V over the field Fequal to the d imensions(V:F). 相似文献
80.
WU Jiada WU Changzheng ZHONG Xiaoxia SONG Zhoumo LI Fuming 《Chinese Journal of Lasers》1997,6(2):161-168
l.IntroductionowingtotheirpromisingproPertiesandPOtentialapplications,transitionmetalni-trideshavedrawngreatattentionandthepreparationandinvestigationofthesecom-poundshavebeenasubjectbothofscientificandoftechnologicalinterest.Transitionmetalnitridescombineadvantagesofexce1lenthardness,highmeltingPOint,goodchemi-calstabilityandhigheIectricalconductivity[11,henceoverlaySofthesecompoundshavefoundwideappIicationsinvariousfie1ds.Molybdenumnitrides,inparticular,havealsoemergedasverypromisingcandi… 相似文献