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The main objective of the paper is to describe asymptotic behaviour of Fourier–Haar coefficients of functions from Marcinkiewicz spaces. We also discuss the Cesàro summability and the almost convergence of sequences related to Fourier–Haar coefficients and generalise a result from [17]. Some analogues of Mercer's theorem for Fourier coefficients are proved. 相似文献
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Dr. Lei Zhang Alexandr Fonari Yue Zhang Guangyao Zhao Dr. Veaceslav Coropceanu Prof. Wenping Hu Dr. Sean Parkin Prof. Jean‐Luc Brédas Prof. Alejandro L. Briseno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(52):17907-17916
Tri‐isopropylsilylethynyl (TIPS)‐functionalized polycyclic aromatic hydrocarbon (PAH) molecules incorporate structural components of graphene nanoribbons and represent a family of model molecules that form organic crystal semiconductors for electronic devices. Here, we report a series of TIPS‐functionalized PAHs and discuss their electronic properties and crystal packing features. We observe that these soluble compounds easily form one‐dimensional (1 D) packing arrangements and allow a direct evolution of the π stacking by varying the geometric shape. We find that the aspect ratio between length and width plays an important role on crystal packing. Our result indicates that when the PAH molecules have zigzag edges, these can provide enough volume for the molecules to rotate and reorient, alleviating the unfavorable electrostatic interactions found in perfectly cofacial π–π stacking. Density functional theory calculations were carried out to provide insights into how the molecular geometric shape influences the electronic structure and transport properties. The calculations indicate that, among the compounds studied here, “brick‐layer” stacks provide the highest hole mobility. 相似文献
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Liliya I. Kasyan Stanislav A. Prid'ma Vitaliy A. Palchikov Leonid D. Karat Alexandr V. Turov Olexandr Isayev 《Journal of Physical Organic Chemistry》2011,24(8):705-713
Reactions of 2‐nitro‐, 4‐nitro‐ and 2,4‐dinitrophenylglycidyl ethers with bicyclo[2.2.1]hept‐5‐ene‐endo‐2‐ylmethylamine in isopropanol have been studied. The mixtures of products were chromatographed on silica gel and eluted with ether or ether/2‐propanol (1:1), the structures of individual products have been confirmed by IR spectra, NMR 1H, 13C spectra, using experiments that involve homonuclear and heteronuclear scalar coupling interactions (COSY, TOCSY, HMQC, HMBC), and mass spectrometry. Amino alcohols as the major products of regioselective aminolysis of epoxides (according to the Krasusky rule) have been obtained. The minor products were the compounds with two hydroxyalkyl fragments at the nitrogen atom. In case of dinitrophenylglycidyl ether, it was the minor product of aryl nucleophilic substitution (SNAr). The abnormal course of aminolysis has been confirmed by the results of quantum‐chemical calculations of activation barries and Free Gibbs energies of the competitive reactions of epoxides (at the B3LYP/6‐311 + G(d,p) level of theory). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Aleshkina SS Likhachev ME Pryamikov AD Gaponov DA Denisov AN Bubnov MM Salganskii MY Laptev AY Guryanov AN Uspenskii YA Popov NL Février S 《Optics letters》2011,36(18):3566-3568
A design of a polarizing all-glass Bragg fiber with a microstructure core has been proposed for the first time. This design provides suppression of high-order modes and of one of the polarization states of the fundamental mode. The polarizing fiber was fabricated by a new, simple method based on a combination of the modified chemical vapor deposition (MCVD) process and the rod-in-tube technique. The mode field area has been found to be about 870 μm2 near λ=1064 nm. The polarization extinction ratio better than 13 dB has been observed over a 33% wavelength range (from 1 to 1.4 μm) after propagation in a 1.7 m fiber piece bent to a radius of 70 cm. 相似文献
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Alexandr Kuznetsov Alice Voronina Vadim Govorun Georgij Arapidi 《Molecules (Basel, Switzerland)》2020,25(22)
Major histocompatibility complex class I (MHC I) plays a crucial role in the development of adaptive immune response in vertebrates. MHC molecules are cell surface protein complexes loaded with short peptides and recognized by the T-cell receptors (TCR). Peptides associated with MHC are named immunopeptidome. The MHC I immunopeptidome is produced by the proteasome degradation of intracellular proteins. The knowledge of the immunopeptidome repertoire facilitates the creation of personalized antitumor or antiviral vaccines. A huge number of publications on the immunopeptidome diversity of different human and mouse biological samples—plasma, peripheral blood mononuclear cells (PBMCs), and solid tissues, including tumors—appeared in the scientific journals in the last decade. Significant immunopeptidome identification efficiency was achieved by advances in technology: the immunoprecipitation of MHC and mass spectrometry-based approaches. Researchers optimized common strategies to isolate MHC-associated peptides for individual tasks. They published many protocols with differences in the amount and type of biological sample, amount of antibodies, type and amount of insoluble support, methods of post-fractionation and purification, and approaches to LC-MS/MS identification of immunopeptidome. These parameters have a large impact on the final repertoire of isolated immunopeptidome. In this review, we summarize and compare immunopeptidome isolation techniques with an emphasis on the results obtained. 相似文献
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Wei W. Chen Ana B. Cuenca Alexandr Shafir 《Angewandte Chemie (International ed. in English)》2020,59(38):16294-16309
Hypervalent organoiodane reagents are ubiquitous in organic synthesis, both as oxidants and as electrophilic group‐transfer agents. In addition to these hallmark applications, a complementary strategy is gaining momentum that exploits the ability of λ3‐iodanes to undergo iodine‐to‐arene group transfer, for example, via iodonio‐Claisen‐type rearrangement processes. This Minireview discusses recent advances in the use of this method to access a variety of the C?H‐functionalized iodoarenes. While Section 2 is focused on the ortho C?H propargylation, allylation, and the more unusual para C?H benzylation, Section 3 is devoted to the C‐arylation of enol and phenol substrates. The accompanying discussion includes mechanistic considerations and goes into the synthetic applications of the final iodoarene cores. The Minireview concludes with further conceptual extensions of the method, including the use of non‐conventional coupling partners (for example, cyanoalkylation), improved access to λ3‐iodane building blocks, and the development of iterative approaches to polysubstituted iodoarenes. 相似文献
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