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Single crystals of the new Bi(III) phosphates, Rb6Bi4(PO4)2(P2O7)3, have been isolated and their structure has been determined by X-ray diffraction techniques. This compound crystallizes in the monoclinic space group P21/c with a=9.077(1)Å, b=9.268(2)Å, c=36.418(6)Å, β=95.75(1)° and Z=8. The crystal structure is made up of BiO5 and BiO6 polyhedra sharing the corners with PO4 tetrahedra and P2O7 diphosphate groups. The structure can be described as infinite anionic layers with composition [Bi4(PO4)2(P2O7)3]∞6− parallel to the [301] plane, connected via P-O-Bi bridges to form a three-dimensional open framework. This framework delimits tunnels running along [100] and [010] directions, where the rubidium ions reside. This compound exhibits a rubidium ion conduction but with rather low conductivity value at 640 K. 相似文献
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Microwave-assisted synthesis of calix[4]resorcinarenes by cyclocondensation of various aldehydes and resorcinol catalysed by 12-tungstophosphoric acid type Keggin (H3PW12O40·13H2O) or concentrated HCl is described. Excellent isolated yields (up to 90%) were attained within short reaction times (typically, 3-5 min) when the reaction was performed under microwaves irradiation. 相似文献
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Madani Moussai 《高校应用数学学报(英文版)》2018,33(2):188-208
Based on the role of the polynomial functions on the homogeneous Besov spaces, on the homogeneous Triebel-Lizorkin spaces and on their realized versions, we study and obtain characterizations of these spaces via difference operators in a certain sense. 相似文献
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Khodayar Gholivand Carlos O. Della Vdova Mauricio F. Erben Fresia Mojahed Ahlam Madani Alizadehgan 《Journal of Molecular Structure》2007,840(1-3):66-70
Using phosphorus pentachloride as a substrate, a new carbacyclamidophosphate, N,N″-bis (2,6-dimethylmorpholino), N″-dichloroacetyl phosphoric triamide (1) has been synthesized and characterized by 1H, 31P and 13C NMR, IR spectroscopy and elemental analysis. Due to the presence of methyl disubstituted morpholine rings and the dichloroacetamide group, several conformers can be considered for this molecule. The 31P{1H} NMR spectra for the isomeric mixture of synthesized compound showed four signals with the ratio 67.1; 19.0; 12.2; 1.7, which indicates four independent conformers. The 1H NMR spectra confirmed these results. The conformational space and the molecular geometry of the molecule in the gaseous phase have been studied using the B3LYP method of approximation, with 6-31G and 6-311++G** basis sets. 相似文献
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Kamyar Madani 《Comptes Rendus Mecanique》2002,330(8):535-541
In the framework of linear elasticity, we consider a composite arch constituted by a matrix and a fiber reinforcing the structure. This arch is clamped at one extremity, while at the other the fibre is subject to either prescribed displacements or forces. By making an asymptotic analysis based on the slenderness and loading parameters, we study by means of an energy criterion the fiber-matrix debonding, resulting from the inextensional displacements of the medium line. We show in particular that for these specific loading types, the debonding occurs brutally and the critical length of initiation is of order 1. To cite this article: K. Madani, C. R. Mecanique 330 (2002) 535–541. 相似文献
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Analysis of Adsorbate–Adsorbate and Adsorbate–Adsorbent Interactions to Decode Isosteric Heats of Gas Adsorption 下载免费PDF全文
S. Hadi Madani Dr. Saeid Sedghi Prof. Mark J. Biggs Prof. Phillip Pendleton 《Chemphyschem》2015,16(18):3797-3805
A qualitative interpretation is proposed to interpret isosteric heats of adsorption by considering contributions from three general classes of interaction energy: fluid–fluid heat, fluid–solid heat, and fluid—high‐energy site (HES) heat. Multiple temperature adsorption isotherms are defined for nitrogen, T=(75, 77, 79) K, argon at T=(85, 87, 89) K, and for water and methanol at T=(278, 288, 298) K on a well‐characterized polymer‐based, activated carbon. Nitrogen and argon are subjected to isosteric heat analyses; their zero filling isosteric heats of adsorption are consistent with slit‐pore, adsorption energy enhancement modelling. Water adsorbs entirely via specific interactions, offering decreasing isosteric heat at low pore filling followed by a constant heat slightly in excess of water condensation enthalpy, demonstrating the effects of micropores. Methanol offers both specific adsorption via the alcohol group and non‐specific interactions via its methyl group; the isosteric heat increases at low pore filling, indicating the predominance of non‐specific interactions. 相似文献
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