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61.
The present paper reports the synthesis, crystal structure, 13C and 111Cd cross-polarization magic-angle spinning nuclear magnetic resonance(CP-MAS-NMR) analysis and ac conductivity for a new organic–inorganic hybrid salt, [C7H12N2][CdCl4]. The compound crystallizes in the triclinic system, space group P\( \overline 1 \), with unit cell dimensions: a?=?7.1050(3) Å, b?=?8.9579(3) Å, c?=?9.4482(3) Å, α?=?81.415(1)°, β?=?89.710(2)°, γ?=?85.765(1)°, V?=?592.97(4) Å3, and Z?=?2. The asymmetric unit is composed of one-2,4-diammonium toluene cation and one [CdCl4]2? anion. The Cd atom is in a slightly distorted octahedra coordination environment. Its structure can be described by infinite chains of CdCl6 octahedron linked to organic cations by a strong charge-assisted N–H???Cl interactions in order to build organic–inorganic layers staked along \( \left[ {0\overline 1 1} \right] \) direction. The solid state 13C CP-MAS-NMR spectra has shown seven isotropic resonances, confirming the existence of seven non-equivalent carbon atoms, which is consistent with crystal structure determined by X-ray diffraction. As for 111Cd MAS-NMR, it has shown one cadmium site with isotropic chemical shift observed at 167.2 ppm. The complex impedance of the compound has been investigated in the temperature range of 403–460 K and in the frequency range of 200 Hz–5 MHz. The impedance plots have shown semicircle arcs at different temperatures and an electrical equivalent circuit has been proposed to explain the impedance results. The circuits consist of the parallel combination of bulk resistance R p and constant phase elements. 相似文献
62.
A new one-dimensional manganese(III) Schiff base complex [Mn(BrSal2MeĐn)(μ1,3-N3)]
n
(I) was synthesized by the reaction of MnCl2 · 6H2O with the Schiff base ligand H2BrSal2MeĐn condensed from 2,2-dimethylpropylenediamine with 5-bromosalicylaldehyde and was characterized by elemental analyses and
FT-IR spectroscopy. The molecular structure of I has been determined from single-crystal X-ray diffraction analysis. In this structure, the Mn3+ ion is in a distorted octahedral geometry with an obvious Jahn-Teller effect, where the deprotonated tetradentate Schiff-base
ligand BrSal2MePn2− is bound in the equatorial plane and the N3− anions show μ1,3-bridging mode in the axial direction. 相似文献
63.
Hichem Elamari Faouzi MeganemJean Herscovici Christian Girard 《Tetrahedron letters》2011,52(6):658-660
Best of both worlds, molecules bearing two alkyne groups, activated and unactivated, can selectively react on the activated one in a copper-free version of Huisgen’s reaction to form a first triazole ring, with a good selectivity toward the 1,4-isomer, which is solely isolated by a simple trituration procedure. The other alkyne function is then submitted to the selective reaction using a polymer-supported copper(I) catalyst to form a second triazole ring. This gave access to disymmetric bistriazoles without the need of protection using simple, easy, and fast procedures. 相似文献
64.
Aliakbar Dehno Khalaji Smail Triki Debasis Das 《Journal of Thermal Analysis and Calorimetry》2011,103(3):779-783
New 1D-chain copper(I) complex [Cu2(μ-(3,4,5-MeO-ba)2bn)(μ-I)2]
n
(1), where (3,4,5-MeO-ba)2bn = N,N′-bis(3,4-dimethoxybenzylidene)-butane-1,4-diamine, involving a new bidentate Schiff-base containing a flexible spacer (=N–C–C–C–C–N=)
has been synthesized and characterized by elemental analyses (CHN) and FT-IR spectroscopy. The crystal structure of 1 was determined from single-crystal X-ray diffraction analyses and shows the (3,4,5-MeO-ba)2en acts as a bridging ligand with the nitrogen atoms of the two imine functions and leading to the dinuclear [Cu2((μ-(3,4,5-MeO-ba)2en)] groups. Such dinuclear [Cu2((μ-(3,4,5-MeO-ba)2en)] groups are bridged by two iodine anions [(μ-I)2] to form a neutral 1D-chain copper(I) iodide coordination polymer. The coordination polyhedron about the copper(I) center
in 1 is best described as a distorted trigonal planar. Thermogravimetric analyses reveal the thermal stability and decomposition
pattern of 1. 相似文献
65.
Tetranuclear copper(II) complex [Cu4(??-Salophen)2(??1,1-N3)2(N3)2] (I) has been synthesized from the reaction of Cu(NO3)2 · 3H2O with the Schiff-base ligand salophen condensed from salicylaldehyde and 1,2-phenylenediamine at the presence of a large excess of NaN3, which has been characterized by elemental analyses, FT-IR spectroscopy, and single-crystal X-ray diffraction. X-ray diffraction studies show that I is a tetranuclear Cu(II) complex with a pair of end-on (EO) azido ions bridging the copper(II) ions in a central Cu(??1,1-N3)2Cu core and one phenoxo bridging the copper(II) ions in a Cu(??-Salophen)Cu core. All copper(II) ions in I are four coordinated and adopt approximate square planar coordination geometry. 相似文献
66.
Mélissa Roger Véronique Patinec Martine Bourgeois Raphaël Tripier Smail Triki Henri Handel 《Tetrahedron》2012,68(27-28):5637-5643
Reaction of triazacyclononane (tacn) and aromatic aldehydes leads to aminal adducts, which exhibit only the exo configuration. In these aminal compounds, secondary amine function possesses a higher reactivity towards electrophilic reactants than the two nitrogen atoms linked to aminal carbon, giving rise to the specific derivatisation of tacn by different functionalised groups. Study of this behaviour also permits the access to a ditopic tacn–cyclam bicyclic polyamine. 相似文献
67.
Lamouchi M Jeanneau E Pillonnet A Brioude A Martini M Stéphan O Meganem F Novitchi G Luneau D Desroches C 《Dalton transactions (Cambridge, England : 2003)》2012,41(9):2707-2713
Two tetranuclear manganese(II) complexes {K(+)[Mn(4)(ThiaSO(2))(2)(OH)](-)} (1) and {K(+)[Mn(4)(ThiaSO(2))(2)(F)](-)} (2) have been synthesized under solvothermal conditions in methanol with p-tert-butylsulfonylcalix[4]arene (ThiaSO(2)). For both complexes, the structure has been established from single-crystal X-ray diffraction. The two complexes are best described as manganese squares sandwiched between two thiacalixarene macrocycles. In both complexes, in the center of the square formed by the four manganese(II) atoms, the unexpected presence of μ(4)-OH(-) or μ(4)-F(-) gives a negative charge to the cluster. The two tetranuclear complexes exhibit strong orange luminescence behavior resulting from the symbiosis between the ThiaSO(2) and the Mn(2+). Despite similar chemical formulation, (1) and (2) present difference in emission intensity and lifetime τ. 相似文献
68.
The structure of K0.92(2) Zn0.08(2) H1.92(2) (PO4) was determined using single-crystal X-ray diffraction. The crystal structure of the Zn-KDP belonged to the tetragonal space group $ \mathrm{I}\overline{4}2\mathrm{d} $ , with cell parameters of a?=?b?=?7.4487(5)?Å and c?=?6.9703(5)?Å, 386.73(5) Å3, Z?=?4, and R?=?0.023. Zn2+ ions were used as substitutes for K+ ions with hydrogen vacancy. The Zn-KDP single crystals were submitted to further Raman, infrared, and 1H NMR studies to investigate chemical group functionalisation, possible bonding between the organic and inorganic materials, and partial substitution of K+ by Zn2+. The latter partial substitution was confirmed by the deviation of IR frequencies for O–H stretching, the variation of IR and Raman frequencies for stretching and bending vibrations ν(PO4) of H2PO4, and the appearance of additional Raman (147, 386 and 481 cm?1) vibrational bands. Electrical conductivity measurements were performed on polycrystalline pellets of Zn-KDP and pure KDP at room temperatures (RT) of up to 473K. In both cases, a conductivity jump close to 453K was observed, and a stronger increase of conductivity was measured. 相似文献
69.
Anjan Biswas Ghodrat Ebadi Houria Triki Ahmet Yildirim Nazila Yousefzadeh 《Results in Mathematics》2013,63(1-2):687-703
This paper studies the KdV–Caudrey–Dodd–Gibbon equation. The modified F-expansion method, exp-function method as well as the G′/G method are used to extract a few exact solutions to this equation. Later, the ansatz method is used to obtain the topological 1-soliton solution to this equation. The constraint conditions are also obtained that must remain valid for the existence of these solutions. 相似文献
70.