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1.
Summary We are going to present the focal-mechanism solution of Fruili earthquake occurred on May 6, 1976, as it results from the analysis, on original seismograms, of the polarities of initial longitudinal waves obtained in 92 seismic stations. The polarities so obtained have been reported on the projection which represents the surface of the Earth and the solution has been drawn, directly, from the study of the resulting distribution, by establishing through Gr?fe's theory the two couples of forces considered as the sources of the seism at the focus. At last, a comparison has been carried out with the solution already obtained by other authors.
Riassunto Si presenta la soluzione del meccanismo focale del terremoto del Fruili del 6/5/1976 ottenuta dallo studio, sui sismogrammi originali, della polarità delle onde longitudinali iniziali, quale si è presentata in 92 stazioni sismiche vicine e lontane. Le polarità ottenute sono state riportate sulla superficie della Terra e la soluzione è stata ricavata direttamente dallo studio della distribuzione così ottenuta, definendo mediante la teoria di Gr?fe le due coppie di forze che hanno agito all'ipocentro. Un confronto è stato infine eseguito con le soluzioni in precedenza ottenute da altri autori.

Резюме Предлагается решение фокального механизма землетрясения, имевшего место в Фриули 6 мая 1976 г. Решение есть результат анализа исходных сейсмограмм, которые получены на 92 сейсмнческих, удаленнынных и близких. Полученные пояьрности представлены в проекции на поверхность Земли. Решение получено непосредственно из исследования результируюшего распределения, которое следует из теории Грефа для для двух пар сил, представляюших источники землетрясения в фокусе. В заключение проводится сравнение с решением, полученным ранее другими авторами.
  相似文献   
2.
In an experiment at the CERN-SPS charged hyperon beam, we have investigated the inclusive \(\Lambda \bar K^0 \) and \(\Sigma ^0 \bar K^0 \) final states formed in Ξ? Be interactions. In the \(\Lambda \bar K^0 \) channel, we observe a signal at 1826 MeV/c2 which can be identified with the known Ξ(1820) resonance. We determine its mass and width to be:M=1826±4 MeV/c2, Г=12±14 MeV/c2. A moment analysis is consistent with a spin of 3/2 and indicates a negative parity for this spin assignment. Also in the \(\Lambda \bar K^0 \) channel, we observe a 3.6σ signal with the following parameters:M=1963±5 MeV/c2, Г=25±15 MeV/c2. This state, which we call Ξ(1960), is not observed in the \(\Sigma ^0 \bar K^0 \) channel, leading to an upper limit on the ratio of partial widths \(\Sigma \bar K/\Lambda \bar K\) of 2.3 (90% confidence level). A moment analysis of the \(\Lambda \bar K^0 \) final state indicates a spin of 5/2 or greater in the natural spin-parity series 5/2+, 7/2?, etc.  相似文献   
3.
The Rm values and retention times of a series of nitroimidazo[2,1-b]thiazoles were obtained by means of thin-layer and high-performance liquid chromatography, respectively. Extrapolated Rm and log k′ values were correlated in a statistically significant way with π values calculated according to the literature.  相似文献   
4.
Some derivatives of 11H-indolo[3,2-c] [1,8]naphthyridine, a new heterocyclic system, have been prepared using the Fischer indole synthesis on the appropriately phenylhydrazones. The preparation of some substituted 5,6-dihydro-11H-indolo[3,2-c][1,8]naphthyridines is also described.  相似文献   
5.
This paper continues the synthesis of new 1,2,3-triazolo[1,2-a]benzotriazoles or 2,3-benzo-1,3a,6,6a-tetrazapentalenes to submit to biological assays. The derivatives were obtained by deoxycyclization reactions of appropriate nitrophenyl-1,2,3-triazole derivatives and by thermal decomposition of appropriate azidophenyl-1,2,3-triazoles (Schemes 1 and 2). Some attempts to extend these synthetic routes to the preparation of 1,2,4-triazolo[1,2-a]benzotriazoles (Scheme 3) and 1,2,3-triazolo[1,2-b]-4H-1,2,3-benzo-triazines (Scheme 4) completely failed.  相似文献   
6.
The 7‐chloro‐3‐(2‐chlorobenzyl)‐ and 7‐chloro‐3‐(2‐fluorobenzyl)‐1,2,3‐triazolo[4,5‐d]pyrimidines ( 1 and 4 ), by nucleophilic replacement with some hydrazides, gave the corresponding 7‐hydrazidoderivatives ( 2a‐e and 5a‐e ). These, by heating in Dowtherm, underwent an intramolecular cyclization to form the new tricyclic 7‐substituted‐3‐(2‐chlorobenzyl)‐ and 3‐(2‐fluorobenzyl)‐1,2,3‐triazolo[4,5‐e]1,2,4‐triazolo[4,3‐c]pyrimidines ( 3a‐d and 6a‐d ). The 7‐hydrazino‐3‐(2‐chlorobenzyl)‐ and 7‐hydrazino‐3‐(2‐fluorobenzyl)‐triazolo‐pyrimidines ( 9a and 9b ) were also prepared via the corresponding mercapto ( 7a and 7b ) and thiomethyl ( 8a and 8b ) derivatives.  相似文献   
7.
8.
The preparation of some 3,7-disubstituted-5,6-dihydroquino[3,2-c][1,8]naphthyridines ( 6 ) by the condensation of 7-substituted-2,3-dihydro-1,8-naphthyridin-4-(1H)ones ( 5 ) with o-aminoacetophenone or o-aminobenzophenone is described. All the 5,6-dihydroderivatives 6 were transformed into the fully aromatic compounds 7 by heating with nitrobenzene. Only a few quino[3,2-c][1,8]naphthyridines were previously described.  相似文献   
9.
Some new 1,2,3-triazolo[4,5-d]-1,2,4-triazolo[4,3-b]pyridazines were prepared starting from the corresponding 1,2,3-triazolo[4,5-d]pyridazines via the formation of the 1,2,4-triazole ring, by condensation of an appropriate monocarbon fragment with the 4-hydrazino substituent and the nitrogen atom in the 5 position of the heterocycle. Condensation of 4-phenylhydrazino substituted derivatives with formic acid gave zwitterionic compounds.  相似文献   
10.
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