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141.
Bob A. Howell Yoseph G. Daniel 《Phosphorus, sulfur, and silicon and the related elements》2020,195(8):638-643
AbstractIsosorbide is a diether diol readily available from starch, an abundant, renewable biomaterial. Because of its structure and functionality, it may serve as a base for the development of nontoxic polymer additives, particularly flame retardants. Conversion of one of the hydroxyl groups to a diphenylphosphato moiety followed by conversion of the other to an acrylate affords isomeric vinyl monomers suitable for copolymerization with a variety of monomers to generate flame-retardant polymers. 相似文献
142.
Gobbi A Funeriu S Ioannou J Wang J Lee ML Palmer C Bamford B Hewitt R 《Journal of chemical information and computer sciences》2004,44(3):964-975
While established pharmaceutical companies have chemical information systems in place to manage their compounds and the associated data, new startup companies need to implement these systems from scratch. Decisions made early in the design phase usually have long lasting effects on the expandability, maintenance effort, and costs associated with the information management system. Careful analysis of work and data flows, both inter- and intradepartmental, and identification of existing dependencies between activities are important. This knowledge is required to implement an information management system, which enables the research community to work efficiently by avoiding redundant registration and processing of data and by timely provision of the data whenever needed. This paper first presents the workflows existing at Anadys, then ARISE, the research information management system developed in-house at Anadys. ARISE was designed to support the preclinical drug discovery process and covers compound registration, analytical quality control, inventory management, high-throughput screening, lower throughput screening, and data reporting. 相似文献
143.
A series of normal aliphatic thiols have been used to derivatise the chemical warfare agents Lewisites I and II (LI and LII) in hydrocarbon matrices. Varying the chain length of the thiol allowed adjustment of derivative tR by 5.9 min for Lewisite I and 5.3 min for Lewisite II. Linear regression analysis of the chain length of the thiol derivatives of the Lewisite species, and that of a series of normal alkanes against tR, allowed regression models to be developed for each set of compounds. Application of the models allowed thiol reagents to be chosen to give derivatives of Lewisites I and II that eluted before and after the major hydrocarbon contaminant. Limits of detection were comparable for all thiol derivatives analysed by GC-MS in the selection ion monitoring mode (all below 1 microg ml(-1)). The robustness of this approach was illustrated by successful identification of Lewisite I in samples from the Sixth Proficiency Test (organised by the Organisation for the Prohibition of Chemical Weapons, OPCW) in a matrix of 1 mg ml(-1) diesel oil. 相似文献
144.
In recent years, inverse analysis has become a common approach to typical engineering problems such as model identification. In this contribution, the inverse problem is discussed in light of taking experimental uncertainties into account. This involves in particular the propagation of experimental errors and the analysis of the sensitivity of the model response to variations in the model parameters to be determined. The method is applied to an elasto-viscoplastic material model which is used in the context of electromagnetic high-speed forming. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
145.
146.
R. Max Dyksterhouse Bob A. Howell Philip J. Squattrito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):64-66
Both the cis, (I), and trans, (II), isomers of the title complex, [PtCl2(C4H7NO)(C2H6OS)], possess relatively undistorted square‐planar geometries about the Pt atoms. For (I), cisL—Pt—L angles are in the range 88.8 (2)–91.08 (8)°, while trans angles are 178.61 (8) and 179.4 (2)°. For (II), cisL—Pt—L 86.1 (3)–93.7 (1)°, and transL—Pt—L 175.5 (1) and 179.1 (3)°. The dimethyl sulfoxide (dmso) ligand adopts a normal pyramidal geometry in both complexes. In (I), the S=O bond essentially eclipses the adjacent Pt—N bond, while the oxazine ligand in (I) is twisted so as to avoid steric interactions with the adjacent chloride ligand. By contrast, the dmso ligand in (II) is rotated such that the S=O bond is approximately perpendicular to the square plane, while the oxazine ligand is once again twisted out of the plane by a similar amount as in (I). These are the first structural examples of square‐planar platinum(II) complexes containing a 1,2‐oxazine ligand. 相似文献
147.
Bergwerff JA van de Water LG Visser T de Peinder P Leliveld BR de Jong KP Weckhuysen BM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(16):4591-4601
The physicochemical processes that occur during the preparation of CoMo-Al2O3 hydrodesulfurization catalyst bodies have been investigated. To this end, the distribution of Mo and Co complexes, after impregnation of gamma-Al2O3 pellets with different CoMoP solutions (i.e., solutions containing Co, Mo, and phosphate), was monitored by Raman and UV-visible-NIR microspectroscopy. From the speciation of the different complexes over the catalyst bodies, insight was obtained into the interaction of the different components in the impregnation solution with the Al2O3 surface. It is shown that, after impregnation with a solution containing H2PMo11CoO40(5-), the reaction of phosphate with the Al2O3 leads to the disintegration of this complex. The consecutive independent transport of Co2+ complexes (fast) and Mo6+ complexes (slow) through the pores of the Al2O3 is envisaged. By the addition of extra phosphate and citrate to the impregnation solution, the formation of the desired heteropolyanion can be achieved inside the pellets. Ultimately, the H2PMo11CoO40(5-) distribution could be controlled by varying the aging time applied after impregnation. The power of a combination of spatially resolved spectroscopic techniques to monitor the preparation of supported catalyst bodies is illustrated. 相似文献
148.
A group of 25 undergraduate students was given seven estimation tasks that involved computation of whole or decimal numbers. The subjects (10 elementary education majors, 7 mathematics majors, and 8 undecided or premajors) were selected because of high achievement in their current college mathematics class. They were asked to estimate an answer to a computational task and then use a calculator provided by the researchers to determine the exact answer. The calculator had been programmed to give incorrect answers that were increasingly higher than the actual answer (beginning with a 10% error and ending with a 50% error). While the majority of subjects produced reasonable estimates, only 7 of the 25 students questioned the accuracy of the answers produced on the calculator. The study points out the subjects’ lack of confidence in estimation skills, as well as a reluctance to question calculator produced results. 相似文献
149.
Shammai Speiser 《Czechoslovak Journal of Physics》1998,48(4):495-506
Intramolecular electronic energy transfer (intra-EET) was investigated in an isolated bichromophoric naphthalene (N) and anthracene
(A) 1:1 molecular cluster. Investigation of the spectroscopic properties of these chromophores, separately and loosely bound
in a van der Waals complex, helps to understand the dependence of the EET rate on the initially excited vibronic level and
on the cluster’s interchromophoric orientation. A slow intra-EET rate that is associated with an unfavoured orientation of
the two chromophores in one of the two possible conformers of the A-N cluster, was observed and was supported by a calculation
of the cluster geometry and by comparison with a recent study of intra-EET in the A-(CH2)n-N bichromophoric molecules.
Presented at the Czech-Israeli-German Symposium “Dynamical Processes in Condensed Molecular Systems”, Prague, Czech Republic,
26–30 May 1997.
This study was partially supported by grants from the VPR Technion — N. Haar and R. Zinn Research Fund and by the Fund for
the Promotion of Research at the Technion. 相似文献
150.