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101.
In this study, 2,9,16,23‐tetrakis‐4′‐(2,3,5,6‐tetrafluoro)‐phenoxy‐phthalocyaninatometalfree and metal(II) complexes, (H2PcBzF16, ZnPcOBzF16, CuPcOBzF16, and CoPcOBzF16) (Bz: Benzene) (2H, Zn, Cu, and Co), have been prepared directly from the corresponding 4′‐(2,3,5,6‐fluorophenylthio)‐phthalonitrile compounds in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in high boiling quinoline solvent. Tetrafluoro atoms on 2,3,5,6‐position of benzene at the peripheral sites of phthalocyanines (Pcs) give rise interesting solubility to tetrakismetallophthalocyanines. Although all complexes were soluble in DCM, CHCl3, THF, DMF, and DMSO with increasing order, complexes synthesized, particularly H2PcBzF16, CuPcOBzF16, have very limited solubility in DMF and DMSO. The complexes have been characterized by elemental analysis, FTIR, 1H NMR, UV–vis, and MALDI–TOF mass spectral data. The cyclic voltammetry and differential pulsed voltammetry of the complexes show that while H2PcBzF16, CuPcOBzF16, and ZnPcOBzF16 give ligand‐based reduction and oxidation processes, CoPcOBzF16 gives both ligand and metal‐based redox processes, in harmony with the common metallophthalocyanine complexes. Redox processes due to both aggregated and disaggregated species were simultaneously observed during the first reduction process. The nature of the metal‐based redox processes was confirmed using spectroelectrochemical measurements. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:262–271, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20545 相似文献
102.
Muharrem Diner Namk
zdemir M. Emin Günay Bekir etinkaya Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):m373-m375
The title complex, [RhBr(C8H12)(C19H22N2O2)], has a distorted square‐planar geometry. There are two molecules, A and B, in the asymmetric unit. The Rh—C bond distance between the N‐heterocyclic ligand and the metal atom is 2.039 (2) Å in molecule A and 2.042 (2) Å in molecule B. The angle between the carbene heterocycle and the coordination plane is 87.56 (12)° in molecule A and 87.03 (11)° in molecule B. It is shown that the average Rh—C(COD) (COD is cyclooctadiene) distance is linearly dependent on the Rh—C(imidazolidine) distance in this type of compound. This can be ascribed to the steric hindrance produced by the packing. The crystal structure contains intramolecular C—H⋯O and intermolecular C—H⋯Br interactions. 相似文献
103.
Exact Solutions for Fractional Differential-Difference Equations by (G′/G)-Expansion Method with Modified Riemann-Liouville Derivative
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Ahmet Bekir Ozkan Guner Burcu Ayhan & Adem C. Cevikel 《advances in applied mathematics and mechanics.》2016,8(2):293-305
In this paper, the ($G′/G$)-expansion method is suggested to establish new
exact solutions for fractional differential-difference equations in the sense of modified
Riemann–Liouville derivative. The fractional complex transform is proposed to convert
a fractional partial differential difference equation into its differential difference
equation of integer order. With the aid of symbolic computation, we choose nonlinear
lattice equations to illustrate the validity and advantages of the algorithm. It is shown
that the proposed algorithm is effective and can be used for many other nonlinear
lattice equations in mathematical physics and applied mathematics. 相似文献
104.
<正>In this paper,we establish travelling wave solutions for some nonlinear evolution equations.The first integral method is used to construct the travelling wave solutions of the modified Benjamin-Bona-Mahony and the coupled Klein-Gordon equations.The obtained results include periodic and solitary wave solutions.The first integral method presents a wider applicability to handling nonlinear wave equations. 相似文献
105.
Aziridines are highly useful compounds as building blocks for the synthesis of important organic compounds. Amino acid synthesis by aziridine ring opening reaction is a good example to the use of aziridines. Although this reaction is studied by many groups, the synthesis of amino phosphonic acids is less explored. In this study, we have carried out the ring opening reaction of aziridinyl phosphonates with a variety of alcohols including the more functional propargylic and allylic alcohols. These reactions provided functionalized α‐amino‐β‐alkoxyphosphonates in 40–91 % yield. 相似文献
106.
Maha S. M. Shehata Hadi Rezazadeh Emad H. M. Zahran Eric Tala-Tebue Ahmet Bekir 《理论物理通讯》2019,71(11):1275-1280
In this article, we employ the perturbed Fokas-Lenells equation(FLE), which represents recent electronic communications. The Riccati-Bernoulli Sub-ODE method which does not depend on the balance rule is used for thefirst time to obtain the new exact and solitary wave solutions of this equation. This technique is direct, effective and reduces the large volume of calculations. 相似文献
107.
In this article,we establish new and more general traveling wave solutions of space-time fractional Klein–Gordon equation with quadratic nonlinearity and the space-time fractional breaking soliton equations using the modified simple equation method.The proposed method is so powerful and effective to solve nonlinear space-time fractional differential equations by with modified Riemann–Liouville derivative. 相似文献
108.
Novel 1,3‐dialkylimidazolidinium, 1,3‐dialkyl‐3,4,5,6‐tetrahydropyrimidinium, and 1,3‐dialkyl‐1H‐4,5,6,7‐tetrahydrodiazepinium hexafluorophosphates ( 1a–c, 2a–c ) as N‐heterocyclic carbene precursors have been synthesized and characterized. The incorporation of saturated N‐heterocyclic carbenes into palladium precatalysts gives high‐catalyst activity in the Heck coupling of aryl bromide substrates in aqueous media. The complexes were generated in the presence of Pd(OAc)2 by in situ deprotonation of 1,3‐dialkylazolinium salts 1, 2 . © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:82–86, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20415 相似文献
109.
New, sterically demanding 1,3‐dialkylbenzimidazolium salts ( 2a–c ) as N‐heterocyclic‐carbene precursors have been synthesized and characterized. The ortho position of aromatic aldehydes was directly and selectively arylated with aryl chlorides in the presence of a catalytic system prepared in situ from Pd(OAc)2, 1,3‐dialkylbenzimidazolium chlorides ( 2a–c ), and Cs2CO3. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:569–574, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20479 相似文献
110.
Photophysical constants of three novel ruthenium dyes derived from tridentate pyridinediimine (pydim) ligands has been declared
and their photoluminescent properties were investigated in solvents of dichloromethane (DCM), tetrahydrofuran (THF) and ethanol
(EtOH) by UV-Visible absorption, emission and excitation spectra. The quantum yield, fluorescence decay time, molar extinction
coefficient and Stoke’s shift values of the novel ruthenium complexes were determined. The perfluoro compound (PFC) nonadecafluorodecanoic
acid which is also known as medical gas carrier has been used for the first time together with newly synthesized Ruthenium
complexes in ethyl alcohol. The utilities of oxygen sensing materials were investigated in EtOH in presence of chemically
and biochemically inert PFC. 相似文献