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A series of 2-aryl-2H-pyrazolo[4,3-c]quinolin-3-ones derivatives 6 and 7 was conveniently prepared. A multistep synthesis was carried out starting from dichloro- and bromoanilines (1a-b) and diethyl 2-(ethoxymethylene)malonate using a slightly modified Gould-Jacobs reaction. In this work we present a novel chlorination strategy to prepare quinoline derivatives 4 in excellent yields as key intermediates in the synthesis of the target compounds. Several reaction conditions were evaluated to optimize the formation of pyrazoloquinolinone nucleus. Differences in chemical behavior of both chloroquinolinones 4a-b with aryl and benzyl-hydrazines are also discussed. 相似文献
45.
Marcelo Kobelnik Douglas Lopes Cassimiro Clóvis Augusto Ribeiro Diógenes dos Santos Dias Marisa Spirandeli Crespi 《Journal of Thermal Analysis and Calorimetry》2010,102(3):1167-1173
Two ONNO type naphtaldehyde derivative Schiff base compounds were reduced and two symmetric phenol-amine ligands containing
naphthalene groups were obtained; bis-N,N′[(2-hydroxy-1-naphtyl) methyl]-1,3-propanediamine (NAFLH) and bis-N,N′[(2-hydroxy-1-naphtyl) methyl]-2,2′-dimetyhyl-1,3-propanediamine (NAFLDMH). Homotrinuclear Ni(II) complexes of these ligands were prepared. The solid-state molecular structures of representative
nickel complex of NAFLDMH were determined using single crystal X-ray diffraction analysis. The terminal Ni(II) ions were found to be situated in between
the donor atoms of the organic ligand. The central Ni(II) ion was observed to be bonded via two different μ-bridges. The phenolic
oxygens and carboxylate ion were seen to form two different μ-bridges. TG analysis proved that the compounds have different
thermal characteristics than those cited in literature. The complexes showed extreme exothermic degradation reactions in inert
atmosphere. The complexes are ruptured with a two stepped exothermic reaction which appears huge heat over 300 °C. The heat
appeared in O2 atmosphere is observed to be higher than the heat appeared in inert atmosphere. Revealed heat is observed to be higher than
the conventional explosive materials. 相似文献
46.
Javier A. Cabeza Prof. Ignacio del Río Prof. Enrique Pérez‐Carreño Prof. Vanessa Pruneda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(18):5425-5436
The cationic cluster complexes [Ru3(μ‐H)(μ‐κ2N,C‐L1 Me)(CO)10]+ ( 1 +; HL1 Me=N‐methylpyrazinium), [Ru3(μ‐H)(μ‐κ2N,C‐L2 Me)(CO)10]+ ( 2 +; HL2 Me=N‐methylquinoxalinium), and [Ru3(μ‐H)(μ‐κ2‐N,C‐L3 Me)(CO)10]+ ( 3 +; HL3 Me=N‐methyl‐1,5‐naphthyridinium), which contain cationic N‐heterocyclic ligands, undergo one‐electron reduction processes to become short lived, ligand‐centered, trinuclear, radical species ( 1 – 3 ) that end in the formation of an intermolecular C? C bond between the ligands of two such radicals, thus leading to neutral hexanuclear derivatives. These dimerization processes are selective, in the sense that they only occur through the exo face of the bridging ligands of trinuclear enantiomers of the same configuration, as they only afford hexanuclear dimers with rac structures (C2 symmetry). The following are the dimeric products that have been isolated by using cobaltocene as reducing agent: [Ru6(μ‐H)2{μ6‐κ4N2,C2‐(L1 Me)2}(CO)18] ( 5 ; from 1 +), [Ru6(μ‐H)2{μ6‐κ4N2,C2‐(L2 Me)2}(CO)18] ( 6 ; from 2 +), and [Ru6(μ‐H)2{μ4‐κ8N2,C6‐(L3 Me)2}(CO)18] ( 7 ; from 3 +). The structures of the final hexanuclear products depend on the N‐heterocyclic ligand attached to the starting materials. Thus, although both trinuclear subunits of 5 and 6 are face‐capped by their bridging ligands, the coordination mode of the ligand of 5 is different from that of the ligand of 6 . The trinuclear subunits of 7 are edge‐bridged by its bridging ligand. In the presence of moisture, the reduction of 3 + with cobaltocene also affords a trinuclear derivative, [Ru3(μ‐H)(μ‐κ2N,C‐L3′ Me)(CO)10] ( 8 ), whose bridging ligand (L3′ Me) results from the formal substitution of an oxygen atom for the hydrogen atom (as a proton) that in 3 + is attached to the C6 carbon atom of its heterocyclic ligand. The results have been rationalized with the help of electrochemical measurements and DFT calculations, which have also shed light on the nature of the odd‐electron species, 1 – 3 , and on the regioselectivity of their dimerization processes. It seems that the sort of coupling reactions described herein requires cationic complexes with ligand‐based LUMOs. 相似文献
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We give sufficient conditions on a real number β and on a closed set F in a general space of homogeneous type (X,d,μ) in such a way that μ(B(x,d(x,F)))β becomes a Muckenhoupt weight. In order to prove our result, we modify the underlying space so that it becomes 1-Ahlfors regular. 相似文献
49.
Sonia de Almeida Evaneide N. Lima Marisa S. Crespi Clóvis A. Ribeiro Valdir Schalch 《Journal of Thermal Analysis and Calorimetry》2009,97(2):529-533
Urban solid residues are constituted of food remaining, grass leaves, fruit peelings, paper, cardboard, rubber, plastic, etc.
The organic fraction formed represents about 50% during the decomposition yields biogas and leachate, which are sources of
pollution. Residue samples were collected from the landfill in different and cells from several ages and the corresponding
leachate, both after treatments, were submitted to thermal analysis. Kinetic parameters were determined using Flynn–Wall–Ozawa
method. The linear relation between the two kinetic parameters (ln A and E) was verified for organic residue urban’s samples, but not for leachate’s sample. The occurred difference can be attributed
to the constituents present in leachate. 相似文献
50.
Sonia Freire H. Casas Esther Rilo Luisa Segade O. Cabeza E. Jiménez 《Journal of Thermal Analysis and Calorimetry》2005,80(2):285-288
Summary In this paper we present excess molar volumes and excess molar enthalpies of binary and ternary mixtures containing propyl propanoate, hexane and cyclohexane as components at 298.15 K. Excess molar volumes were calculated from the density of the pure liquids and mixtures. The density was measured using an Anton Paar DMA 60/602 vibrating-tube densimeter. Excess molar enthalpies were obtained using a Calvet microcalorimeter 相似文献