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611.
Edelson-Averbukh M Shevchenko A Pipkorn R Lehmann WD 《Journal of the American Society for Mass Spectrometry》2011,22(12):2256-2268
Unambiguous differentiation between isobaric sulfated and phosphorylated tyrosine residues (sTyr and pTyr) of proteins by mass spectrometry is challenging, even using high resolution mass spectrometers. Here we show that upon negative ion mode collision-induced dissociation (CID), pTyr- and sTyr-containing peptides exhibit entirely different modification-specific fragmentation patterns leading to a rapid discrimination between the isobaric covalent modifications using the tandem mass spectral data. This study reveals that the ratio between the relative abundances of [M-H-80](-) and [M-H-98](-) fragment ions in ion-trap CID and higher energy collision dissociation (HCD) spectra of singly deprotonated +80 Da Tyr-peptides can be used as a reliable indication of the Tyr modification group nature. For multiply deprotonated +80 Da Tyr-peptides, CID spectra of sTyr- and pTyr-containing sequences can be readily distinguished based on the presence/absence of the [M-nH-79]((n-1)-) and [M-nH-79-NL]((n-1)-) (n=2, 3) fragment ions (NL=neutral loss). 相似文献
612.
Measurement of the appearance of an object consists of a group of measurements to characterize the color and surface finish
of the object. This group of measurements involves the spectral energy distribution of propagated light measured in terms
of reflectance and transmittance, and the spatial energy distribution of that light measured in terms of the bidirectional
reflectance distribution function (BRDF). In this article we present the virtual gonio-spectrophotometer, a device that measures
flux (power) as a function of illumination and observation. Virtual gonio-spectrophotometer measurements allow the determination
of the scattering profile of specimens that can be used to verify the physical characteristics of the computer model used
to simulate the scattering profile. Among the characteristics that we verify is the energy conservation of the computer model.
A virtual gonio-spectrophotometer is utilized to find the correspondence between industrial measurements obtained from gloss
meters and the parameters of a computer reflectance model. 相似文献
613.
Structural properties of effective potential model by liquid state theories 总被引:1,自引:0,他引:1 下载免费PDF全文
This paper investigates the structural properties of a model fluid dictated by an effective inter-particle oscillatory potential by grand canonical ensemble Monte Carlo (GCEMC) simulation and classical liquid state theories.The chosen oscillatory potential incorporates basic interaction terms used in modeling of various complex fluids which is composed of mesoscopic particles dispersed in a solvent bath,the studied structural properties include radial distribution function in bulk and inhomogeneous density distribution profile due to influence of several external fields.The GCEMC results are employed to test the validity of two recently proposed theoretical approaches in the field of atomic fluids.One is an Ornstein-Zernike integral equation theory approach;the other is a third order + second order perturbation density functional theory.Satisfactory agreement between the GCEMC simulation and the pure theories fully indicates the ready adaptability of the atomic fluid theories to effective model potentials in complex fluids,and classifies the proposed theoretical approaches as convenient tools for the investigation of complex fluids under the single component macro-fluid approximation. 相似文献
614.
Christopher M. Dobson Andrej ali Martin Karplus 《Angewandte Chemie (International ed. in English)》1998,37(7):868-893
The mechanism of protein folding (represented schematically below) is one of the most fascinating problems in the field of chemical reactions. This review presents the progess made recently in understanding key elements of this reaction and describes a solution to the often quoted Levinthal Paradox. 相似文献
615.
Vladimir V. Ivanov Alexandr A. Yurchenko Alexander N. Chernega Alexandr M. Pinchuk Andrej A. Tolmachev 《Heteroatom Chemistry》2002,13(1):84-92
A number of 4,5‐dihydrobenzo[e]imidazo[2,1‐c][1,4,2]diazaphosphinine derivatives were prepared by the direct phosphorylation of 1‐(4‐Chlorophenylcarboxamido)‐2‐(1H‐1‐imidazolyl)‐5‐trifluoromethylbenzene in basic medium with phosphorus(III) bromide and dibromophenylphosphine. The tricyclic compounds 6a, 6b , and 9 having a trivalent phosphorus atom undergo the diazaphosphinine ring opening upon treatment with secondary amines in the presence of sulfur. © 2002 John Wiley & Sons, Inc. Heteroatom Chem 13:84–92, 2002; DOI 10.1002/hc.10000 相似文献
616.
Dominika Valachová Michaela Marčeková Dr. Oľga Caletková Dr. Andrej Kolarovič Dr. Pavol Jakubec 《European journal of organic chemistry》2023,26(13):e202201341
Protodenitration, a direct reduction of nitroalkanes to corresponding alkanes, already spans two centuries and is enabled by various reagents. This mini-review provides a historical development of the fundamental transformation and highlights the governing position of the Ono-Tanner reaction employing tributyltin hydride. Due to the unchallenged dominance of the toxic tributyltin hydride and environmentally unpopular solvents sharply contrasting with modern ecological trends, the current situation was dubbed “the last fortress of tin's tyranny.” 相似文献
617.
Čegovnik Tomaž Dobrovoljc Andrej Povh Janez Rogar Matic Tomšič Pavel 《Central European Journal of Operations Research》2023,31(3):833-851
Central European Journal of Operations Research - The measurement of electricity consumption at 15-minute granularity, including for households, is increasingly mandated in the EU and this also... 相似文献