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281.
Wilczura-Wachnik H Yavuz AG Myslinski A 《Journal of colloid and interface science》2008,319(2):520-525
The experimental data of heat of mixing (Q) for heterogeneous system alpha-tocopherol/AOT/n-heptane with and without water at 25 degrees C are presented. The Q dependence on AOT (sodium bis (2-ethylhexyl) sulfosuccinate) concentration, and R parameter defined as R=[H2O]/[AOT] with flow calorimetric method were investigated. Using the D'Aprano model (which is formally identical to that used earlier by Magid et al.) the binding constant (K), the distribution constant of alpha-tocopherol (K distr) between hydrocarbon and the micellar phase, and the standard enthalpy of transfer (DeltaH tr 0) of alpha-tocopherol from the hydrocarbon to AOT reversed micelles were calculated. The solubility of alpha-tocopherol in AOT reversed micelles explored with the calorimetric technique was compared to the literature data obtained respectively with UV spectrophotometry for reversed micelles and by other techniques for the phospholipid bilayer. 相似文献
282.
Atenolol dithiocarbamate (ADTC) and its complexes with Cu(II), Co(II), Ni(II), Zn(II), and Cd(II) have been synthesized. These
newly synthesized products have been characterized by elemental analyses (C, H, N, and S), thermal (thermogravimetry (TG)
and differential thermal analyses (DTA)) as well as by spectral (UV, IR, and NMR (1H)) studies. The stability constants (β) of metal complexes of ADTC have been determined by UV-Vis data in solutions in DMSO.
The antimicrobial activities of the metal complexes have been screened in vitro against ten bacteria.
The text was submitted by the authors in English. 相似文献
283.
Onur Yavuz 《Transactions of the American Mathematical Society》2008,360(5):2661-2680
Consider an annulus for some , and let be a bounded invertible linear operator on a Banach space whose spectrum contains . Assume there exists a constant such that and for all polynomials . Then there exists a nontrivial common invariant subspace for and .
284.
S(0), S(1), and T(1) states of various orthogonal 8,8' and 8,2'-bis-boradiaza-s-indacene (BODIPY) dyes, recently (Angew. Chem., Int. Ed.2011, 50, 11937) proposed as heavy atom free photosensitizers for O(2)((1)Δ(g)) generation, were studied by multireference quantum chemical approaches. S(0)→S(1) excitation characteristics of certain bis-BODIPYs are shown to be drastically different than the parent BODIPY chromophore. Whereas a simple HOMO→LUMO-type single substitution perfectly accounts for the BODIPY core, S(1) states of certain orthogonal bis-BODIPYs are described as linear combinations of doubly substituted (DS) configurations which overall yield four electrons in four singly occupied orbitals. Computed DS character of S(1), strongly correlated with facile (1)O(2) production, was presumed to occur via S(1)→T(1) intersystem crossing (ISC) of the sensitizer. Further confirmation of this relation was provided by newly synthesized BODIPY derivatives and comparison of spectroscopic properties of their dimers and monomers. Near-IR absorption, desired for potential photodynamic therapy applications, was not pursuable for bis-chromophores by the standard strategy of π-extension, as DS singlet states are destabilized. Decreased exchange coupling in π-extended cases appears to be responsible for this destabilization. Comparisons with iodine incorporated bis-BODIPYs suggest that the dynamics of (1)O(2) generation via DS S(1) states are qualitatively different from that via ISC originating from heavy atom spin-orbit coupling. Although red-shifting the absorption wavelength to enter the therapeutic window does not seem attainable for orthogonal bis-BODIPYs with DS S(1) states, modifications in the chromophore cores are shown to be promising in fine-tuning the excitation characteristics. 相似文献
285.
Synthesis of four different types of ligands Ar[COC(NOH)R]
n
(Ar = biphenyl, n = 1, HL1; Ar = biphenyl, n = 2, H2L2; Ar = diphenylmethane, n = 1, HL3; Ar = diphenylmethane, n = 2, H2L4; R = furfurylamine in all ligands) and their dinuclear Co2+, Ni2+, Cu2+, and Zn2+ complexes is reported herein. These compounds were characterized by elemental analysis, ICP-OES, FT-IR spectra, and magnetic
susceptibility measurements. The ligands were further characterized by 1H NMR. The results suggest that dinuclear complexes of HL1 and HL3 have a metal to ligand mole ratio of 2: 2 and dinuclear complexes H2L2 and H2L4 have a metal to ligand mole ratio of 2: 1. Square pyramidal or octahedral structures are proposed for complexes of oxime
ligands. Furthermore, extraction abilities of the four ligands were also evaluated in chloroform using selected transition
metal picrates such as Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pb2+. The ligands show strong binding ability towards Hg2+ and Cu2+ ions. 相似文献
286.