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21.
A. Merle 《Progress in Particle and Nuclear Physics》2010,64(2):445-447
In this talk, a short discussion of the GSI anomaly is given. We discuss the physics involved using a comparison with pion decay, and explain why the observed oscillations cannot be caused by standard neutrino mixing. 相似文献
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23.
Let N be a regular chain-group on E (see W. T. Tutte, Canad. J. Math.8 (1956), 13–28); for instance, N may be the group of integer flows or tensions of a directed graph with edge-set E). It is known that the number of proper Zλ-chains of N (λ ∈ Z, λ ≥ 2) is given by a polynomial in λ, P(N, λ) (when N is the chain-group of integer tensions of the connected graph G, λP(N, λ) is the usual chromatic polynomial of G). We prove the formula: P(N, λ) = Σ[E′]∈O(N)+/~Q(R[E′](N), λ), where O(N)+ is the set of orientations of N with a proper positive chain, ~ is a simple equivalence relation on O(N)+ (sequence of reversals of positive primitive chains), and Q(R[E′](N), λ) is the number of chains with values in [1, λ ? 1] in any reorientation of N associated to an element of [E′]. Moreover, each term Q(R[E′](N), λ) is a polynomial in λ. As applications we obtain: P(N, 0) = (?1)r(N)∥O(N)+/~∥; P(N, ?1) = (?1)r(N)∥O(N)+∥ (a result first proved by Brylawski and Lucas); P(N, λ + 1) ≥ P(N, λ) for λ ≥ 2, λ ∈ Z. Our result can also be considered as a refinement of the following known fact: A regular chain-group N has a proper Zλ-chain iff it has a proper chain in [?λ + 1, λ ? 1]. 相似文献
24.
We report the high resolution emission (S1 → S0, T1 → S0) and laser single site singlet excitation (S1 ← S0) spectra for the various insertion sites of coronene in n-heptane cooled to 1.5 K. The observation of site splitting of doubly degenerate vibrations and weak electric dipole forbidden 0, 0 bands in the S1 → S0 and T1 → S0 spectra indicates that the ground state, the first excited singlet and lowest triplet states are all distorted. In these spectra, the intensity distribution of the various sites in the 0, 0 bands suggests that the distortion is different from site to site but similar in S0, S1 and T1. Identical ordering of the sites in S1 S0 and S1 S0 spectra as well as the observation of weak shifts in the vibrational frequencies in the two states implies the absence of strong pseudo Jahn-Teller forces in the first excited singlet state. We propose, further, that this is also true for the triplet state. This conclusion is supported by the similarity in zero-field splitting parameters of coronene and deuterated coronene. Taken together, these results indicate strongly that the distortion of coronene in n-heptane is primarily crystal field induced and is not greatly changed upon excitation of the molecule to its lowest excited states. 相似文献
25.
Merle A. Battiste Billy G. GriggsJr Debra Sackett 《Journal of organometallic chemistry》1987,330(3):437-446
The cyclopentadienylnickel complex (2) and the parent dimethyl norbornadienedicarboxylate (4) each react with 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene (3) on the less hindred exo-face of the dienophile to produce anti-sequinorbornane adducts 5 and 6. X-ray crystal structures of these adducts have been determined and refined to R values of 0.029 and 0.042 respectively. 相似文献
26.
Frank Merle 《Communications in Mathematical Physics》1990,129(2):223-240
We consider the nonlinear Schrödinger equation: (1) $${{i\partial u} \mathord{\left/ {\vphantom {{i\partial u} {\partial t}}} \right. \kern-\nulldelimiterspace} {\partial t}} = - \Delta u - \left| u \right|^{{4 \mathord{\left/ {\vphantom {4 N}} \right. \kern-\nulldelimiterspace} N}} uandu\left( {0,.} \right) = \varphi \left( . \right),$$ whereu:[0,T)×? N →?. For any given pointsx 1,x 2,...,x k in ? N , we construct a solution of Eq. (1),u(t), which blows up in a finite timeT at exactlyx 1,x 2,...,x k . In addition, we describe the precise behavior of the solutionu(t) whent→T, at the blow-up points {x 1,x 2,...,x k } and in ? N ?{x 1,x 2,...,x k }. 相似文献
27.
D. G. Middleton J. R. M. Annand C. Barbieri P. Barneo P. Bartsch D. Baumann J. Bermuth D. Bosnar H. P. Blok R. Böhm M. Ding M. O. Distler D. Elsner J. Friedrich C. Giusti D. I. Glazier P. Grabmayr S. Grözinger T. Hehl J. Heim W. H. A Hesselink E. Jans F. Klein M. Kohl L. Lapikás I. J. D. MacGregor I. Martin J. C. McGeorge H. Merkel P. Merle F. Moschini U. Müller Th. Pospischil G. Rosner H. Schmieden M. Seimetz A. Süle H. de Vries Th. Walcher D. P. Watts M. Weis B. Zihlmann 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):469-469
28.
29.
William R. Dolbier Jr. Yian Zhai Wei Xu Will Wheelus Florian Dulong Efram Goldberg Ion Ghiviriga Merle A. Battiste 《Journal of fluorine chemistry》2008,129(12):1133-1138
When 4-nitro-AF4 is treated with nucleophiles such as alkoxides and cyanide, a novel ring opening, cyclophane destroying reaction is observed whereby, via an SNAr mechanism, the nucleophile attacks the bridgehead aryl carbon vicinal to the nitro group with subsequent aryl-CF2 bond cleavage. 相似文献
30.
We study the energy-critical focusing non-linear wave equation, with data in the energy space, in dimensions 3, 4 and 5. We
prove that for Cauchy data of energy smaller than the one of the static solution W which gives the best constant in the Sobolev embedding, the following alternative holds. If the initial data has smaller
norm in the homogeneous Sobolev space H
1 than the one of W, then we have global well-posedness and scattering. If the norm is larger than the one of W, then we have break-down in finite time. 相似文献