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131.
Donato Pocar Luisa Maria Rossi Pasqualina Trimarco 《Journal of heterocyclic chemistry》1979,16(5):925-927
Some enamines derived from α-diketones have been reacted with tosylazide yielding unstable 5-amino-υ-triazolines, which were found to undergo cyeloreversion to diazo compounds and arnidines. In the case of the enamines derived from 4-aryl-2,3-butanediones, a competitive rearrangement to (Z)-4-aryl-4-arnino-3-tosylamino-3-butene-2-ones was observed. 相似文献
132.
Nilo Zanatta Simone S. Amaral Josiane M. dos Santos Liana da S. Fernandes Helio G. Bonacorso Marcos A. P. Martins 《Journal of heterocyclic chemistry》2011,48(5):1085-1090
The regioselective synthesis and characterization of a new series of 3‐aryl‐7‐trifluoromethyl[1,2,4]triazolo[4,3–a]pyrimidines from the oxidative heterocyclization of 2‐(N′‐benzylidenehydrazino)‐4‐trifluoromethylpyrimidines with copper dichloride is described. J. Heterocyclic Chem., (2011). 相似文献
133.
A new cooper benzenedicarboxylate metal-organic coordination polymer,[Cu(μH2O)(BDC)]n·nDMF(1,H2BDC = 1,4-benzenedicarboxylate acid,DMF = N,N'-dimethylfor-mamide),has been successfully synthesized under hydrothermal conditions and characterized by IR spectroscopy,elemental analysis,thermogravimetric analysis and single-crystal X-ray diffraction.This complex crystallizes in triclinic,space group P1 with a = 6.605,b = 10.44780(10),c = 11.0881(6) ,α = 62.064(11),β = 73.410(15),γ = 78.404(16)°,C11H13CuNO6,Mr = 318.76,V = 645.79(8) 3,Z = 2,Dc = 1.639 g/cm3,F(000) = 326,μ = 1.712 mm-1,the final R = 0.0362 and wR = 0.1330 for 2055 observed reflections with I > 2σ(I).The title compound contains infinite inorganic chains constructed by Cu oxygen octahedra by sharing corners and edges.Each chain is connected by BDC linkers to four other chains to form a three-dimensional framework with irregular rhombic channels where the DMF molecules are encapsulated. 相似文献
134.
A facile nickel-catalyzed method to achieve the amination of synthetically useful aryl sulfamates and carbamates is reported. Contrary to most Ni-catalyzed amination reactions, this user-friendly approach relies on an air-stable Ni(II) precatalyst, which, when employed with a mild reducing agent, efficiently delivers aminated products in good to excellent yields. The scope of the method is broad with respect to both coupling partners and includes heterocyclic substrates. 相似文献
135.
Erra L Tedesco C Cipolletti VR Annunziata L Gaeta C Brunelli M Fitch AN Knöfel C Llewellyn PL Atwood JL Neri P 《Physical chemistry chemical physics : PCCP》2012,14(1):311-317
The adsorption properties of a new nanoporous organic zeolite with respect to acetylene and Ar were studied by volumetric adsorption analysis, microcalorimetric experiments, and synchrotron high-resolution X-ray powder diffraction. This allowed us to locate the guest molecules inside the host channels and characterize the host-guest interactions. 相似文献
136.
Liana David 《Geometriae Dedicata》2013,167(1):189-214
Let $\pi :V\rightarrow M$ be a (real or holomorphic) vector bundle whose base has an almost Frobenius structure $(\circ _{M},e_{M},g_{M})$ and typical fiber has the structure of a Frobenius algebra $(\circ _{V},e_{V},g_{V})$ . Using a connection $D$ on the bundle $\pi : V{\,\rightarrow \,}M$ and a morphism $\alpha :V\rightarrow TM$ , we construct an almost Frobenius structure $(\circ , e_{V},g)$ on the manifold $V$ and we study when it is Frobenius. In particular, we describe all (real) positive definite Frobenius structures on $V$ obtained in this way, when $M$ is a semisimple Frobenius manifold with non-vanishing rotation coefficients. In the holomorphic setting, we add a real structure $k_{M}$ on $M$ and a real structure $k_{V}$ on the bundle $\pi : V \rightarrow M$ . Using $k_{M}$ , $k_{V}$ and $D$ we define a real structure $k$ on the manifold $V$ . We study when $k$ , together with an almost Frobenius structure $(\circ , e_{V}, g) $ , satisfies the tt*- equations. Along the way, we prove various properties of adding variables to a Frobenius manifold, in connection with Legendre transformations and $tt^{*}$ -geometry. 相似文献
137.
Chi Kwong Chang 《中国化学快报》2009,20(1):21-24
Chiral bis-corrole 1 and 2 were prepared by reaction of(s)-2,2′-bis(bromomethyl)-1,1′-binaphthyl and 10-(4-hydroxylphenyl)- 5,15-bis(pentafluorophenyl)corrole or 10-(3-hydroxylphenyl)-5,15-bis(pentafluorophenyl)corrole in DMF at 60℃in the presence of anhydrous K_2CO_3 with an isolated yield~8%.Both 1 and 2 exhibit unsymmetrical induced circular dichroism(ICD)in the soret band with positive exciton chirality. 相似文献
138.
We provide a general criterion for the integrability of the almost para-quaternionic structure of an almost para-quaternionic manifold of dimension 4m8 in terms of the integrability of two or three sections of the defining rank three vector bundle . We relate it with the integrability of the canonical almost complex structure of the twistor space and with the integrability of the canonical almost para-complex structure of the reflector space of . We deduce that has plenty of locally defined, compatible, complex and para-complex structures, provided that is integrable. 相似文献
139.
Let the manifold X parametrise a family of compact complex submanifoldsof the complex (or CR) manifold Z. Under mild conditions thePenrose transform typically provides isomorphisms between acohomology group of a holomorphic vector bundle V Z and thekernel of a differential operator between sections of vectorbundles over X. When the spaces in question are homogeneousfor a group G the Penrose transform provides an intertwiningoperator between representations. The paper develops a Penrose transform for compactly supportedcohomology on Z. It provides a number of examples where a compactlysupported cohomology group is shown to be isomorphic to thecokernel of a differential operator between compactly supportedsections of vector bundles over X. It considers also how theSerre duality pairing carries through the transform. 相似文献
140.
Socaciu LD Hagen J Bernhardt TM Wöste L Heiz U Häkkinen H Landman U 《Journal of the American Chemical Society》2003,125(34):10437-10445
Temperature-dependent rf-ion trap mass spectrometry and first-principles simulations reveal the detailed reaction mechanism of the catalytic gas-phase oxidation of CO by free Au(2)(-) ions in the presence of O(2). A metastable intermediate with a mass of Au(2)CO(3)(-) was observed at low temperatures. Two alternative structures corresponding to digold carbonate or peroxyformate are predicted for this intermediate. Both structures are characterized by low activation barriers for the formation of CO(2). These combined experimental and theoretical investigations provide a comprehensive understanding of the kinetics, energetics, and atomic arrangements along the reaction path, thus allowing a formulation of the catalytic cycle for the oxidation reaction. 相似文献