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排序方式: 共有334条查询结果,搜索用时 31 毫秒
41.
E. Juárez Hurtado O. H. Miyagaki R. S. Rodrigues 《Journal of Dynamics and Differential Equations》2018,30(2):405-432
In this paper we establish, using variational methods, the existence and multiplicity of weak solutions for a general class of quasilinear problems involving \(p(\cdot )\)-Laplace type operators, with Dirichlet boundary conditions involving variable exponents without Ambrosetti and Rabinowitz (A-R) type growth conditions, namely By different types of versions of the Mountain Pass Theorem with Cerami condition, as well as, the Fountain and Dual Theorem with Cerami condition, we obtain some existence of weak solutions for the above problem under some considerations. Moreover, we show that the problem treated has at least one nontrivial solution for any parameter \(\lambda >0\) small enough, and also that the solution blows up, in the Sobolev norm, as \(\lambda \rightarrow 0^{+}.\) Finally, by imposing additional hypotheses on the nonlinearity \(f(x,\cdot ),\) we get the existence of infinitely many weak solutions by using the Genus Theory introduced by Krasnoselskii.
相似文献
$$\begin{aligned} \left\{ \begin{array}{rcll} -{\text {div}}(a(|\nabla u|^{p(x)})|\nabla u|^{p(x)-2}\nabla u)&{}=&{}\lambda f(x,u) &{} \text{ in } \Omega ,\\ u&{}=&{}0 &{} \text{ on } \partial \Omega . \end{array} \right. \end{aligned}$$
42.
采用正电子寿命谱和拉曼散射研究了不同组分配比的Ge Sex(x=6,7,8,9)硫系玻璃的微结构.正电子寿命结果显示在x=8时,其平均正电子寿命具有最小值.拉曼光谱结果研究表明,这种硫系玻璃样品主要由[Ge Se4]四面体和Seμ链的结构单元构成.以上的实验结果用级配理论得到了合理的解释,这两种结构单元配比关系的变化导致硫系玻璃样品中的自由体积变化,从而导致正电子平均寿命减小.研究发现Ge Se8具有最小的自由体积,即具有最稳定的结构. 相似文献
43.
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45.
阴离子分散剂对酸化膨润土流变性的影响 总被引:1,自引:0,他引:1
研究了阴离子分散剂聚丙烯酸钠对质量分数为10%的酸化膨润土分散体系流变性的影响. 结果表明, 添加0.4%分散剂的分散体系的剪切应力、表观黏度和屈服应力最低. 其它体系流体均表现为从假塑型到胀流型流体的转变, 而含0.4%分散剂的体系始终表现为胀流型流体. 采用Herschel-Bulkley模型对各体系的流变曲线进行了拟合, 得到较好的拟合曲线, 同时探讨了酸化膨润土分散体系的流变机理. 相似文献
46.
47.
John Hurtado Alvaro Muñoz-Castro Raúl Quijada René Rojas Mauricio Valderrama 《Journal of organometallic chemistry》2009,694(16):2636-223
Reactions of 2,6-bis(bromomethyl)pyridine with 3,5-dimethylpyrazole and 1H-indazole yield the terdentate ligands 2,6-bis(3,5-dimethylpyrazol-1-ylmethyl)pyridine (5) and 2,6-bis(indazol-2-ylmethyl)pyridine (6). The molecular structure of the new compound 6 was determined by single-crystal X-ray diffraction. These ligands react with the CrCl3(THF)3 complex in THF to form neutral complexes of general formula [CrCl3{2,6-bis(azolylmethyl)pyridine-N,N,N}] (7, 8) which are isolated in high yields as stable green solids and characterized by means of elemental analysis, magnetic moments, IR, and mass spectroscopy. Theoretical calculations predict that the thermodynamically preferred structure of the complexes is the fac configuration. After reaction with methylaluminoxane (MAO) the chromium(III) complexes are active in the polymerization of ethylene. 相似文献
48.
Matching Points with Squares 总被引:1,自引:0,他引:1
Bernardo M. Ábrego Esther M. Arkin Silvia Fernández-Merchant Ferran Hurtado Mikio Kano Joseph S. B. Mitchell Jorge Urrutia 《Discrete and Computational Geometry》2009,41(1):77-95
Given a class
of geometric objects and a point set P, a
-matching of P is a set
of elements of
such that each C
i
contains exactly two elements of P and each element of P lies in at most one C
i
. If all of the elements of P belong to some C
i
, M is called a perfect matching. If, in addition, all of the elements of M are pairwise disjoint, we say that this matching M is strong. In this paper we study the existence and characteristics of
-matchings for point sets in the plane when
is the set of isothetic squares in the plane. A consequence of our results is a proof that the Delaunay triangulations for
the L
∞ metric and the L
1 metric always admit a Hamiltonian path. 相似文献
49.
Prosenjit Bose Vida Dujmović Ferran Hurtado Stefan Langerman Pat Morin David R. Wood 《Discrete and Computational Geometry》2009,42(4):570-585
To untangle a geometric graph means to move some of the vertices so that the resulting geometric graph has no crossings. Pach and Tardos (Discrete Comput. Geom. 28(4): 585–592, 2002) asked if every n-vertex geometric planar graph can be untangled while keeping at least n ε vertices fixed. We answer this question in the affirmative with ε=1/4. The previous best known bound was \(\Omega(\sqrt{\log n/\log\log n})\). We also consider untangling geometric trees. It is known that every n-vertex geometric tree can be untangled while keeping at least \(\Omega(\sqrt{n})\) vertices fixed, while the best upper bound was \(\mathcal{O}((n\log n)^{2/3})\). We answer a question of Spillner and Wolff (http://arxiv.org/abs/0709.0170) by closing this gap for untangling trees. In particular, we show that for infinitely many values of n, there is an n-vertex geometric tree that cannot be untangled while keeping more than \(3(\sqrt{n}-1)\) vertices fixed. 相似文献
50.
ZHANG Yu-chi PI Zi-feng LIU Chun-ming SONG Feng-rui LIU Zhi-qiang LIU Shu-ying 《高等学校化学研究》2012,28(1):31-36
A high performance liquid chromatography coupled with electrospray ionization-tandem mass spectrometry( HPLC-ESI-MS/MS) method was developed for the analysis and identification of ginsenosides in the extracts of raw Panax ginseng(RPG) and steamed Panax ginseng at high temperatures(SPGHT). A total of 25 ginsenosides were extracted include of which 10 low-polar ginsenosides, such as ginsenosides F4, Rk3, Rh4, 20S-Rg3, 20R-Rg3 and so on, were identified according to their HPLC retention time and MS/MS data. The results indicated that the low polar ginsenosides were seldom found in RPG. For the exploration of the transformation pattern of the ginsenosides in steam processing, the standards of ginsenosides Re, Rg1, Rb1, Rc, Rb2, Rb3 and Rd were selected and hydrolyzed at a temperature of 120 ℃. The results show that these polar ginsenosides can be converted to low-polar ginsenosides such as Rg2, Rg6, F4, Rk3 and Rg5 by hydrolyzing the sugar chains. 相似文献