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141.
L. V. Tsymbal L. M. Pogorelaya Ya. D. Lampeka 《Theoretical and Experimental Chemistry》2005,41(1):58-63
We have established that a bis(azamacrocyclic) complex of copper(II) with 1,3,5-benzenetricarboxylate undergoes reversible dehydration/rehydration processes. The rate of these processes and the high sensitivity of the material obtained to water vapor permit us to consider this compound as a promising coating for humidity sensors. Furthermore, such a coating differentiates between methanol and other monohydric alcohols.__________Translated from Teoreticheskaya i Éksperimentalnaya Khimiya, Vol. 41, No. 1, pp. 55–59, January–February, 2005. 相似文献
142.
One‐Pot Synthesis of Highly Substituted 1H‐Pyrazole‐5‐carboxylates from 4‐Aryl‐2,4‐diketoesters and Arylhydrazines
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Jiao‐Jiao Zhai Chun‐Hui Gu Ying Guo Dao‐Hua Liao Dun‐Ru Zhu Ya‐Fei Ji 《Journal of heterocyclic chemistry》2016,53(3):840-848
A one‐pot synthesis of highly substituted 1H‐pyrazole‐5‐carboxylates 1 has been developed starting from easily available 4‐aryl‐2,4‐diketoesters 2 and arylhydrazine hydrochlorides 3 . More active 2‐carbonyl group of 2 was blocked with methoxyamine hydrochloride to give 2‐methoxy imine intermediates, which were then subjected to condensation cyclization with 3 in situ to provide the desired products 1 . In addition, the geometrical configuration of 1aa was unambiguously confirmed by single crystal X‐ray crystallography. 相似文献
143.
Kinga Suwinska Janusz S. Lipkowski Yuri A. Dyadin V.Yu. Komarov Irina S. Terekhova Tatyana V. Rodionova Andrey Yu. Manakov 《Journal of inclusion phenomena and macrocyclic chemistry》2006,56(3-4):331-335
In this work X-ray single crystal structural analysis was carried out on the clathrate hydrate of tetraisoamylammonium propionate with the composition (i-C5H11)4NC2H5CO2·36H2O. The hydrate was found to have an orthorhombic structure in space group Cmc2 1 with unit cell parameters: a = 21.281(2) Å, b= 12.010(7) Å, c = 24.768(3) Å (150 K). X-ray powder diffraction studies were performed of the hydrate phase, crystallized in the water–(i-C5H11)4NC2H5CO2 system in the concentration range of the salt (10–25 wt%) that is the crystallization region of the studied polyhydrate, according to the phase equilibria data. It was found, that in the given concentration region the same hydrate of orthorhombic structure is formed, unit cell parameters, obtained at 20 °C: a = 21.454(13) Å, b = 12.156(4) Å, c = 25.030(14) Å, are in a good agreement with the data of single crystal structural analysis. 相似文献
144.
145.
Ten polymeric silver(I) double salts containing embedded acetylenediide: [(Ag2C2)2(AgCF3CO2)9(L1)3] (1), [(Ag2C2)2(AgCF3CO2)10(L2)3]H2O (2), [(Ag2C2)(AgCF3CO2)4(L3)(H2O)]0.75 H2O (3), [(Ag2C2)(1.5)(AgCF3CO2)7(L4)2] (4), [(Ag2C2)(AgCF3CO2)7(L5)2(H2O)] (5), [(Ag2C2) (AgC2F5CO2)7(L1)3(H2O)] (6), [(Ag2C2)(AgCF3CO2)7(L1)3(H2O)]2 H2O (7), [(Ag2C2)(AgC2F5CO2)6(L3)2] (8), [(Ag2C2)2(AgC2F5CO2)12(L4)2(H2O)4]H2O (9), and [(Ag2C2)(AgCF3CO2)6(L3)2(H2O)]H2O (10) have been isolated by varying the types of betaines, the perfluorocarboxylate ligands employed, and the reaction conditions. Single-crystal X-ray analysis has shown that 1-4 all have a columnar structure composed of fused silver(I) double cages, with C2(2-) species embedded in its stem and an exterior coat comprising anionic and zwitterionic carboxylates. For 5 and 6, single silver(I) cages are linked into a beaded chain through both types of carboxylate ligands. In 7, two different coordination modes of L1 connect the silver(I) polyhedra into a chain. For 8, the mu(2)-O,O' coordination mode of L3 connects the silver(I) double cages into a chain. Compound 9 exhibits a two-dimensional architecture generated from the cross-linkage of double cages by C2F5CO2-, L4, and [Ag2(C2F5CO2)2] units. Similar to 9, 10 is also a two-dimensional structure, which is formed by connecting the chains of linked double cages through [Ag2(CF3CO2)2] bridging. 相似文献
146.
使Zn(OAc)2·2H2O或Cd(OAc)2·2H2O与邻羧基苯甲酰二茂铁钠(o-OOCC6H4COFcNa;Fc=(η5-C5H5)Fe(η5-C5H4))和1,10-邻菲咯啉(phen)在甲醇中反应,合成了含有混合配体的单核配合物[Zn(o-OOCC6H4COFc)2(phen)(H2O)]·CH3OH (1)和双核配合物{[Cd(η2-o-OOCC6H4COFc)( μ2-o-OOCC6H4COFc)(phen)]·CH3OH2·H2O}2 (2)。晶体结构表明:在1中,单核的结构单元通过分子间氢键形成了一维的长链结构;在2中,o-FcCOC6H4COO-以及phen均双齿螯合中心Cd(II)离子,随后在o-FcCOC6H4COO-的双齿桥联下,形成一个双核结构。研究了这2个配合物在DMF溶液中的电化学性能。 相似文献
147.
The crystal structures of two monomeric copper(II) carboxylates with 2-aminopyridine have been determined by X-ray diffraction. The hexanoate complex crystallizes as its acetonitrile solvate [Cu(C6H11O2)2(C5H6N2)2 · CH3CN] in the triclinic space group P-1 with a = 8.1020(6), b = 13.7106(9), c = 13.7673(9) Å, = 113.79(1), = 103.86(1), and = 94.38(4). The heptanoate compound shows an unsolvated structure [Cu(C7H13O2)2(C5H6N2)2] and also crystallizes in the triclinic space group P-1 with the following cell parameters: a = 8.4487(9), b = 12.238(1), c = 13.504(2) Å, = 87.034(9), = 77.489(9), and = 71.41(1)°. Both compounds contain the CuO4N2 chromophore, with ligands arranged around the copper center in a cis mode. 2-Aminopyridine is coordinated through the endocyclic nitrogen atom. The ortho position of the amino group, with respect to the pyridine nitrogen atom, allows the formation of both, intra-and intermolecular hydrogen bonds. 相似文献
148.
Antonella Salvini Carlo Giannelli Luca Rosi 《Journal of organometallic chemistry》2005,690(2):371-382
The reactivity of phosphine substituted ruthenium carbonyl carboxylates Ru(CO)2(MeCOO)2(PBu3)2, Ru2(CO)4(μ-MeCOO)2(PBu3)2, Ru4(CO)8(μ-MeCOO)4(PBu3)2 with H2 and/or acetic acid was investigated by IR and NMR spectroscopy to clarify their role in the catalytic hydrogenation of acetic acid. Evidences were collected to suggest hydride ruthenium complexes as the catalytically active species. Equilibria among ruthenium hydrides and carboxylato complexes take place in the presence of hydrogen and acetic acid, that is in the conditions of the catalytic reaction. Nevertheless the presence of acetic acid reduces the rate of the formation of hydrides. Working at a very high temperature (180°C) polynuclear phosphido hydrides such as [Ru6(μ-H)6(CO)10(μ-PHBu)(μ-PBu2)2(PBu3)2(μ6-P)] were formed. These phosphido clusters are suggested as the resting state of the catalytic system.Furthermore the bi- or tetranuclear Ru(I) carboxylato complexes react with acetic acid giving a mononuclear ruthenium complex Ru(CO)2(MeCOO)(μ-MeCOO)(PBu3), containing a monodentate and a chelato acetato ligands. This complex was spectroscopically characterised. Its identity and structure were confirmed by its reactivity with stoichiometric amount of PPh3 to give Ru(CO)2(MeCOO)2(PBu3)(PPh3), a new mononuclear ruthenium carbonyl carboxylate containing two different phosphines, that was fully characterised. 相似文献
149.
N. S. Vrandečić I. Klarić T. Kovačić 《Journal of Thermal Analysis and Calorimetry》2003,74(1):171-180
The thermooxidative degradation of poly(vinyl chloride) (PVC), chlorinated polyethylene (CPE) and PVC/CPE blend 50/50 was
investigated by means of dynamic and isothermal thermogravimetric analysis in the flowing atmosphere of air. To estimate the
thermooxidative stability of the samples the characteristics of thermogravimetric (TG) curves were used. Kinetic parameters
(the apparent activation energy E and preexponential factor Z) were calculated after isoconversional method for the first
stage of dynamic degradation where dehydrochlorination (DHCl) of PVC and/or CPE is the main degradation reaction. Despite
the chemical resemblance, the degradation mechanisms of CPE and PVC are different, as a consequence of differences in microregularity
of the corresponding polymer chains. The addition of Ca/Zn carboxylates as well as the ratio of Ca and Zn carboxylates have
considerably different influence on the investigated polymers.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
150.
The mediated oxidation of acetate and octanoate ions in acetonitrile was used to covalently modify carbon surfaces with films bearing saturated aliphatic chains of different length. Film thickness increases proportionally with the length of the aliphatic chain within the carboxylate precursor. The thickest film was obtained from octanoate oxidation and rectification occurs when ferrocene is used as redox probe in acetonitrile solution. This effect increases with the bulky and hydrophobic nature of the supporting electrolyte cations; n-Hx4N+>n-Bu4N+>Me4N+. The combination of the bulky and hydrophobic properties of the supporting electrolyte ions as well as the hydrophobic properties of the electrografted films is the basis of rectification of ferrocene in cyclic voltammetry experiments. This phenomenon was simulated through a CEC mechanism in solution, where the mass transport inside the film channels was emulated through single chemical equilibria. 相似文献