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1.
Synthesis of Ultra-High Molecular Weight Polyolefins of Regular Structure in Octafluorobutane Medium
Rasputin N. A. Yakovlev S. V. Artem’ev G. A. Rusinov P. G. Nifant’ev I. E. Nikonov I. L. Kopchuk D. S. 《Russian Journal of Applied Chemistry》2021,94(6):736-740
Russian Journal of Applied Chemistry - The suspension polymerization in octafluorobutane, initiated by Ziegler–Natta catalyst system, has been used to synthesize ultra-high molecular weight... 相似文献
2.
Aishabibi Kassymbek Prof. Dmitry G. Gusev Dr. Anton Dmitrienko Prof. Melanie Pilkington Prof. Georgii I. Nikonov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103455
Reaction of the Ga(I) compound NacNacGa ( 9 ) with the diazo compound N2CHSiMe3 affords the nitrilimine compound NacNacGa(N-NCSiMe3)(CH2SiMe3) ( 10 ). Carrying out this reaction in the presence of pyridine does not lead to C−H activation on the transient alkylidene NacNacGa=CHSiMe3 but generates a metallated diazo species NacNacGa(NHN=CHSiMe3)(CN2SiMe3) ( 13 ) that further rearranges into the isonitrile compound NacNacGa(NHN=CHSiMe3)(N(NC)SiMe3) ( 15 ). Reactions of 10 with the silane H3SiPh and the borane HBcat furnished products of 1,3 addition to the nitrilimine moiety NacNacGa{N(ERn)NCSiMe3}(CH2SiMe3), whereas reaction with the diborane B2cat2 gave the product of formal nitrene insertion into the B−B bond. DFT calculations suggest that the interaction of 9 with N2CHSiMe3 proceeds through intermediate formation of an alkylidene compound that undergoes CH activation with a second molecule of N2CHSiMe3. Insertion into the B−B bond likely proceeds through an initial 1,3-addition of the diborane, followed by boryl migration to the former nitrene center. 相似文献
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6.
Anton Dmitrienko Prof. Melanie Pilkington Prof. Georgii I. Nikonov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(18):5730-5736
The AlI compound NacNacAl ( 1 , NacNac = [ArNC(Me)CHC(Me)NAr]−, Ar = 2,6-iPr2C6H3) serves as a template for the chemoselective coupling between carbonyls (benzophenone, fenchone, isophorone, p-tolyl benzoate, N,N-dimethylbenzamide, (1-phenylethylidene)aniline) and pyridine. With the CH-acidic ketone (1R)-(+) camphor, the reaction affords a hydrido alkoxide compound of Al, formed as the result of enolization, whereas an enolizable imine, (1-phenylethylidene)aniline, and the bulky ketone isophorone, still chemoselectively couple with pyridine. In contrast, reaction with the ester p-tolyl benzoate results in cleavage of the ester bond together with replacement of the alkoxy group by a hydrogen atom of the pyridine moiety. This study demonstrates that for carbonyl substrates featuring phenyl substituents, the reaction proceeds via intermediate formation of η2(C,X)-coordinated (X = O, N) carbonyl adducts, whereas the reaction of 1 with (R)-(−)-fenchone in the absence of pyridine leads to CH activation in the pendant isopropyl group of the Ar substituent of the NacNac ligand. 相似文献
7.
A. V. Anisovich E. Klempt V. A. Nikonov A. V. Sarantsev U. Thoma 《The European Physical Journal A - Hadrons and Nuclei》2011,47(2):27
We report evidence for N(1710)P
11 , N(1875)P
11 , N(1900)P
13 , D \Delta(1600)P
33 , D \Delta(1910)P
31 , and D \Delta(1920)P
33 , and find indications that N(1900)P
13 might have a companion state at 1970MeV. The controversial D \Delta(1750)P
31 is not seen. The evidence is derived from a study of data on pion- and photo-induced hyperon production, but other data are
included as well. Most of the resonances reported here were found in the Karlsruhe-Helsinki (KH84) and the Carnegie-Mellon
(CM) analyses but were challenged recently by the Data Analysis Center at GWU. Our analysis is constrained by the energy-independent
p \pi
N scattering amplitudes from either KH84 or GWU. The two p \pi
N amplitudes from KH84 or GWU, respectively, lead to slightly different p \pi
N branching ratios of contributing resonances but the debated resonances are required in both series of fits. 相似文献
8.
Nikonov M. V. Vinokurov S. E. Myasoedov B. F. 《Russian Journal of Applied Chemistry》2020,93(11):1705-1709
Russian Journal of Applied Chemistry - The amount of hydrogen peroxide formed in aqueous solutions directly in the course of microwave irradiation is considerably larger than the amounts detected... 相似文献
9.
Kseniya Revunova Dr. Georgii I. Nikonov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(3):839-845
Simple bases (KOtBu, KOH) catalyze the silane‐promoted reduction of ketones and esters to alcohols and of aldimines to amines. The inexpensive silane PMHS (polymethylhydrosiloxane) can be used as the reducing reagent. Double and triple bonds, as well as nitro‐ and cyano‐groups are tolerated. Careful dosing of the silane allows for chemoselective reduction of a more reactive group in the presence of a less reactive group (for example, aldehyde reduction in the presence of ketone/ketone reduction in the presence of ester group). Mechanistic studies showed that addition of base to silanes leads to silicate species, which are the acting reducing agents. Under basic conditions, hydrosiloxanes (tetramethyldisiloxane, TMDS; PMHS) convert into simple silanes (H2SiMe2, H3SiMe), making this a practical method to generate these challenging silanes. 相似文献
10.