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31.
In 1996, we reported that silyl groups of 9,10-disilylanthracenes significantly affect the UV/Vis and fluorescence spectra. Although the results indicate that the silyl groups have strong electronic effects on anthracene, the details of the mechanisms responsible for this have not yet been clarified. This article describes the analysis of the UV/Vis and fluorescence spectra of 9,10-bis(diisopropylsilyl)anthracene by theoretical calculations. This study reveals that π conjugation of anthracene is extended by cooperation of σ–π and σ*–π* conjugation between the silyl groups and anthracene. This effect increases the transition moment of the π–π* transition of anthracene. As a result, the molecular extinction coefficient of the 1La band and the fluorescence quantum yield are increased. 相似文献
32.
本文研究了具有卷积的中心自反环的性质,定义并引入了中心-自反环,显然,中心-自反环是自反环、中心自反环和-自反环的推广.给出了这类环的一些特征,研究了相关的环扩张,包括平凡扩张,Dorroh扩张和多项式扩张. 相似文献
33.
34.
Gabriel Nagy 《Proceedings of the American Mathematical Society》2002,130(4):1065-1071
We prove that the value of the quasi-trace on an idempotent element in an AW*-factor of type is the same as the dimension of its left (or right) support.
35.
Let , be -algebras and a full Hilbert --bimodule such that every closed right submodule is orthogonally closed, i.e., . Then there are families of Hilbert spaces , such that and are isomorphic to -direct sums , resp. , and is isomorphic to the outer direct sum .
36.
魏文国 《高校应用数学学报(A辑)》1996,(1):105-112
本文主要讨论了欧拉图方面的国际权威HerbertFleichner教授所著书[1]中的一个问题;对欧拉图G的任意两个欧拉游历要经过多少K-变换或K^*-变换才能从一个游历得到另一个游历?我们得到的结论是:对欧拉图G中的任两个欧拉游历T、T'最多经过‖E(G)‖-‖V(G)‖-变换可以使T变换成T'。且此结果不能再改进。进一步我们分别对K-变换和K&-变换的算法复杂性进行了讨论。 相似文献
37.
P-正则半群的双序集 总被引:1,自引:0,他引:1
本文刻划了双序集E为某P-正则半群的幂等元双序集的充要条件.所得定理不仅推广了D.Easdown关于带的双序集的结论,而且导出了正则*-半群的幂等元双序集的一个刻划.进而还对P-正则半群的若干特殊情形及向非正则半群的推广进行了讨论. 相似文献
38.
推导了两能级原子在稳态和小速度一阶微扰近似下的受力矢量方程,并分析表明TEM01模光场以原子的作用力中存在旋涡力,对在大正失谐δ〉〉Ω0〉〉Г和z〈〈z0=kw^2/λ条件下的TEM01模行波和驻波场中原子的受力进行了分析,对行波场,自发辐射对原子运动的影响很大,但在r〈〈λ区域内原子受到横向囚禁力;对驻波场,自发辐射的影响可以忽略,考虑在z方向波长范围内原子的平均受力得到的结论为:在横向,除了有 相似文献
39.
Chun-Gil Park 《Bulletin of the Brazilian Mathematical Society》2005,36(1):79-97
It is shown that every almost linear mapping
of a unital Poisson JC*-algebra
to a unital Poisson JC*-algebra
is a Poisson JC*-algebra homomorphism when h(2
n
uy) = h(2
n
u) h(y), h(3
n
u y) = h(3
n
u) h(y) or h(q
n
u y) = h(q
n
u) h(y) for all
, all unitary elements
and n = 0, 1, 2, · · · , and that every almost linear almost multiplicative mapping
is a Poisson JC*-algebra homomorphism when h(2x) = 2h(x), h(3x) = 3h(x) or h(qx) = qh(x) for all
. Here the numbers 2, 3, q depend on the functional equations given in the almost linear mappings or in the almost linear almost multiplicative mappings.Moreover, we prove the Cauchy–Rassias stability of Poisson JC*-algebra homomorphisms in Poisson JC*-algebras.*This work was supported by grant No. R05-2003-000-10006-0 from the Basic Research Program of the Korea Science & Engineering Foundation. 相似文献
40.
Jochen Lutz The Vinh Ho Richard H. Fish Andreas Schmid 《Journal of organometallic chemistry》2004,689(25):4783-4790
The biocatalytic, regioselective hydroxylation of 2-hydroxybiphenyl to the corresponding catechol was accomplished utilizing the monooxygenase 2-hydroxybiphenyl 3-monooxygenase (HbpA). The necessary natural 1,4-dihydronicotinamde adenine dinucleotide (NADH) co-factor for this biocatalytic process was replaced by a biomimetic co-factor, N-benzyl-1,4-dihydronicotinamide, 1b. The interaction between the flavin (FAD) containing HbpA enzyme and the corresponding biomimetic NADH compound, N-benzyl-1,4-dihdronicotinamide, 1b, for hydride transfer, was shown to readily occur. The in situ recycling of the reduced NADH biomimic 1b from 1a was accomplished with [Cp*Rh(bpy)H](Cl); however, productive coupling of this regeneration reaction to the enzymatic hydroxylation reaction was not totally successful, due to a deactivation process concerning the HbpA enzyme peripheral groups; i.e., -SH or -NH2 possibly reacting with the precatalyst, [Cp*Rh(bpy)(H2O)](Cl)2, and thus inhibiting the co-factor regeneration process. The deactivation mechanism was studied, and a promising strategy of derivatizing these peripheral -SH or -NH2 groups with a polymer containing epoxide was successful in circumventing the undesired interaction between HbpA and the precatalyst. This latter strategy allowed tandem co-factor regeneration using 1a or 2a, [Cp*Rh(bpy)(H2O)](Cl)2, and formate ion, in conjunction with the polymer bound, FAD containing HbpA enzyme to provide the catechol product. 相似文献