首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   155篇
  免费   21篇
  国内免费   26篇
化学   49篇
力学   4篇
综合类   1篇
数学   130篇
物理学   18篇
  2021年   1篇
  2019年   4篇
  2018年   3篇
  2017年   3篇
  2016年   2篇
  2015年   2篇
  2014年   8篇
  2013年   20篇
  2012年   9篇
  2011年   7篇
  2010年   10篇
  2009年   5篇
  2008年   16篇
  2007年   22篇
  2006年   11篇
  2005年   10篇
  2004年   8篇
  2003年   10篇
  2002年   10篇
  2001年   6篇
  2000年   6篇
  1999年   4篇
  1998年   3篇
  1997年   4篇
  1996年   2篇
  1995年   4篇
  1994年   4篇
  1992年   1篇
  1990年   2篇
  1988年   1篇
  1985年   1篇
  1984年   2篇
  1936年   1篇
排序方式: 共有202条查询结果,搜索用时 9 毫秒
61.
Considering the Julia set J(Tλ) of the Yang-Lee zeros of the Potts model on the diamond hierarchical Lattice on the complex plane, the authors proved that HDJ(Tλ) 〉 1 and discussed the continuity of J(Tλ) in Hausdorff topology for λ∈R.  相似文献   
62.
Letf be a holomorphic self-map of the punctured plane ℂ*=ℂ\{0} with essentially singular points 0 and ∞. In this note, we discuss the setsI 0(f)={z ∈ ℂ*:f n (z) → 0,n → ∞} andI (f)={z ∈ ℂ*:f n (z) → 0,n → ∞}. We try to find the relation betweenI 0(f),I (t) andJ(f). It is proved that both the boundary ofI 0(f) and the boundary ofI )f) equal toJ(f),I 0(f) ∩J(f) ≠ θ andI (f) ∩J(f) ≠ θ. As a consequence of these results, we find bothI 0(f) andI (f) are not doubly-bounded. Supported by the National Natural Science Foundation of China  相似文献   
63.
On the Simple Connectivity of Fatou Components   总被引:1,自引:0,他引:1  
We shall show that for certain holomorphic maps, all Fatou components are simply connected. We also discuss the relation between wandering domains and singularities for certain meromorphic maps. Received May 8, 2002, Accepted May 24, 2002  相似文献   
64.

Let be a quadratic rational map of the sphere which has two fixed Siegel disks with bounded type rotation numbers and . Using a new degree Blaschke product model for the dynamics of and an adaptation of complex a priori bounds for renormalization of critical circle maps, we prove that can be realized as the mating of two Siegel quadratic polynomials with the corresponding rotation numbers and .

  相似文献   

65.
The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl d-malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia olefination have been employed as the key steps.  相似文献   
66.
A convergent total synthesis of the novel antifungal agent ambruticin S (1) has been completed from the assembly of intermediates 18, 33 and 52 that served as the respective A-, B-, and C-ring precursors. The first generation approach to a potential A-ring intermediate eventuated in the synthesis of 9a via a route that featured oxidation of the dihydroxy furan 2 and elaboration of the dihydropyranone 3 derived therefrom. Although 9a served as a precursor of 31E to complete a formal synthesis of 1, there were several inefficiencies associated with the preparation of 9a. A more expedient and efficient route to an A-ring subunit was devised that commenced with the carbohydrate-derived bisacetonide aldehyde 10 and produced 18 in five steps and 46% overall yield. The synthesis of the cyclopropyl sulfone 33 was initiated with the enantioselective cyclopropanation of 19 catalyzed by Rh2[5(S)-MEPY]4. Ring opening of the resultant lactone 20 followed by a series of refunctionalizations gave 33 in a total of seven steps and 46% yield from 19. Coupling of the A- and B-ring precursors 18 and 33 was then achieved via a modified Julia coupling followed by deprotection and oxidation to furnish the key intermediate 35. The dihydropyran core of the C-ring subunit precursor 49 was formed from the ring closing metathesis of the diene 48, which was prepared in three steps from the known epoxide 45, followed by oxidation. A chelation-controlled addition to the methyl ketone 49 set the stage for a stereoselective [2,3]-Wittig rearrangement that delivered the alcohol 51 that was then transformed in two steps to the sulfone 52. A traditional Julia coupling of 52 and 35 proceeded with excellent stereoselectivity, and subsequent removal of the various protecting groups gave ambruticin S (1). The longest linear sequence was 13 steps and proceeded in 4.3% overall yield.  相似文献   
67.
In this paper, we study the dynamics of the family of rational maps fλ,(z) = zn - λ/zm, n ≥2, m ≥ 1,λ ∈ C. We construct an example of buried Sierpinski curve Julia set in this family. We also give an estimate of the location of bifurcation locus of fλ.  相似文献   
68.
肖映青  邱维元 《数学学报》2010,53(2):323-328
用P表示一个度为d的首一多项式,J_P表示它的Julia集.本文得到Julia集J_P和其等势线Γ_P(R)上的d~n-阶Chebyshev多项式,并举例说明二者并不总是相等.  相似文献   
69.
DynamicsofPolynomialAutomorphismsofC~N¥ZhangWenjun(HenanUniversity,Kaifeng,P.R.Chian,475001)Abstract:Thispaperisassignedtodis?..  相似文献   
70.
In this paper, we prove that two rational maps with the Cantor Julia sets are quasicon- formally conjugate if they are topologically conjugate.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号