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51.
由于N-杂环卡宾结构的多样性,以及它们的金属络合物良好的稳定性和催化活性,近年来受到了人们的广泛关注。本文对N-杂环卡宾及其金属络合物的性质和合成方法进行了综述。参考文献30篇。 相似文献
52.
The title compound, 5-N-i-propyl-2-(2′-nitrobenzenesulfonyl)-glutamine, was synthesized and its structure was confirmed by IR, MS, 1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2 (1), with a = 0.69281(11) nm, b = 0.76508(12), c = 1.5843(3) nm, = 90°, β = 90.941(3)°, γ = 90°, V = 0.8397(2) nm3, Z = 2, Dc = 1.477 g/cm3, μ = 0.236 mm-1, F(000) = 392, R = 0.0297, and wR = 0.0664. 相似文献
53.
LI Wen-ming WANG Jian-guo LI Zheng-ming SONG Hai-bin 《高等学校化学研究》2008,24(3):295-298
2-Chloro-N-{2-fluoro-5-[N-(phenylsulfonyl)phenylsulfonamido]phenyl}benzamide was synthesized and its crystal structure was also determined by X-ray single-crystal diffraction. The title compound(C25H18ClFN2O5S2) belongs to monoclinic, space group P21/n with a=0.7377(3) nm, b=1.2036(5) nm, c=2.6846(11) nm, β=90.895(9)°, V=2.3833(16) nm3, Mr=544.98, Z=4, Dc=1.519 g/cm3, μ=0.385 mm–1, F(000)=1120, R1=0.0632, and wR2=0.1438. Its crystal structure belongs to a novel class that has not been reported yet, and its preliminary herbicidal activity was also tested. Its inhibition rate to seedling growth of barnyard grass reaches 15.1% at 100 μg/mL. 相似文献
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55.
L-shell partial production cross sections of Lα-, Lβ-, Lγ- rays by electron impact were measured by observing the counts of X-ray from impacted thin tungsten target. Total production cross sections and mean ionization cross sections were deduced from these measured results. The electron beam energy range was from 11 to 36 keV. Tungsten was sputtered onto a carbon backing to reduce bremsstrahlung of the backing. The effect of electrons reflected by the backing has been corrected. Comparison with two theoretical calculations has performed. The experimental results agree rather well with the theoretical predications. 相似文献
56.
黄争鸣 《应用数学和力学(英文版)》1992,13(10):951-966
The purpose of this paper is to analyse theoretically and numerieally the coupled vibration of an ideal fiuid with a linear elastie structure.It is proved in the paper that the natural frequencies of the coupled vibration do exist and are all real positive. The paper presents an efficient method to transform a coupled fluid-structure system to the structure with added mass and the ribrational analysis of the former is replaced by the latter in vacuum only. Numerical solution is outlined for the transformed problem and a compact frequecy equation is derived in which fluid variables do not appear. This simplifies the analysis significanily. A convergent proof has been given to guarantee the reliability of the solution. The paper also offers a general algorithm combined with Ritz method, boundary element method, and finite element method to analyse the transformed problem. Based on this algorithm, one can apply a known structural analysing program, with a little modification, to solve many different kinds 相似文献
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58.
Thirteen novel phenyl substituted isoxazolecarboxamides were synthesized, and their structures were characterized by 1H NMR, elementary analysis and high-resolution mass spectrometry(HRMS) techniques. Their evaluated insecticidal activities against oriental armyworm(Mythimna separata) indicate that the phenyl substituted isoxazolecarboxamides exhibited moderate insecticidal activities, among which compounds 9c and 9k showed comparatively higher activities. 相似文献
59.
2-(Dimethylamino)-1,3-dithiocyanatopropane(1) has been prepared as a key intermediate synthesizing a natural insecticide Cartap by the reaction of 1-dimethylamino-2,3-dichloropropane with sodium thiocyanate. The crystal structures of compound 1 and its isomer 1-(dimethylamino)-2,3-dithiocyanotopropane(2) formed during the reaction were determined by X-ray single-crystal diffraction. Bond lengths in both the compounds are common and fall within normal ranges. There are some weak C―H×××N hydrogen bonds in the lattice of compound 1, which makes it form a three-dimensional network, which stabilize the crystal structure. No classic hydrogen bonds were founded in its isomer(2), only van der Waals forces contribute to the stability of the structure. In addition, DFT and MP2 calculations with 6-311+G(d, p) basis set have also been carried out to investigate the thermodynamic properties of compounds 1 and 2. The research will be applied to the further investigation of the tautomerization of compounds 1 and 2. 相似文献
60.
A series of new sulfonylureas incorporating 1,2,4-triazolinone moiety was synthesized, which were further bio-assayed for the herbicidal activity against four herbs, representative of monocotyledons and dicotyledons. Some of them exhibited high potency to inhibit the growth of dicotyledons(Bassica napus and Amaranthus retroflexus) in the pot experiment. Compounds 9a and 9b also displayed an excellent herbicidal activity against Bassica napus at a concentration of 15 g/hectare, which were comparable with commercial triasulfuron. 相似文献