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排序方式: 共有220条查询结果,搜索用时 31 毫秒
91.
Dufton JT Walsh A Panchmatia PM Peter LM Colombara D Islam MS 《Physical chemistry chemical physics : PCCP》2012,14(20):7229-7233
As the demand for photovoltaics rapidly increases, there is a pressing need for the identification of new visible light absorbing materials for thin-film solar cells that offer similar performance to the current technologies based on CdTe and Cu(In,Ga)Se(2). Metal sulphides are the ideal candidate materials, but their band gaps are usually too large to absorb significant fractions of visible light. However, by combining Cu(+) (low binding energy d(10) band) and Sb(3+)/Bi(3+) (low binding energy s(2) band), the ternary sulphides CuSbS(2) and CuBiS(2) are formed, which have been gathering recent interest for solar cell applications. Using a hybrid density functional theory approach, we calculate the structural and electronic properties of these two materials. Our results highlight the stereochemical activity of the Sb and Bi lone pair electrons, and predict that the formation of hole carriers will occur in the Cu d(10) band and hence will involve oxidation of Cu(I). 相似文献
92.
C-Jun N-terminal kinase (JNK) is a therapeutic target for inhibitors which may provide clinical benefit in the pathogenesis of rheumatoid arthritis (RA) as well as in various apoptosis-related disorders. The benzothiazol-2-yl acetonitrile derivatives, recently reported by Pascale et al. (J. Med. Chem. 2005, 48, 4596-4607), are the first generation JNK inhibitors of this class. To understand inhibitory mechanisms and elucidate pharmacophoric properties of these derivatives molecular docking and 3D-QSAR studies were performed on a set of 44 compounds. Ligand Fit module of Cerius2 (4.9) was employed to locate the binding orientations of all the compounds within the JNK-3 ATP binding site. A good correlation (r2=0.810) between the calculated binding free energies (-PMF score) and the experimental inhibitory activities suggests that the identified binding conformations of these potential inhibitors are reliable. Based on the binding conformations, robust and highly predictive 3D-QSAR models were developed with conventional r2 0.886 and 0.802, full cross-validation r2 0.980 and 0.788, and predictive r2 0.965 and 0.968 for MFA and MSA, respectively. The interaction mode was demonstrated taking into consideration inhibitor conformation, hydrogen bonding, and electrostatic interaction. The 3D-QSAR model built in this study will provide clear guidelines for a novel inhibitor design based on the benzothiazole derivatives against JNK-3 for the treatment of inflammatory disorders. 相似文献
93.
The toxicological effects, biological aspects and spectral characterization of organoboron(III) complexes of sulfonamide‐imines derived by the condensation of salicylaldehyde with different sulfa‐drugs are described. The benzene‐soluble, high‐molecular‐weight complexes have been characterized using a wide range of analytical and spectroscopic techniques, viz. UV, IR, 1H and 11B NMR. On the basis of these studies, it is inferred that the imines derived from sulfa drugs and salicylaldehyde behave as dibasic tridentate ligands and thus provide a tetrahedral environment around the boron atom. Finally, all these complexes have been screened for their antimicrobial activity against a variety of fungal and bacterial strains and their toxicological effects on male albino rats examined at the dosages employed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
94.
95.
An efficient and practical route to novel fluorescent benzo[a]pyrano[2,3-c]phenazine framework has been developed by one-pot, four-component reaction of 2-hydroxynaphthalene-1,4-dione, 1,2-phenylenediamines, aromatic aldehydes, and Meldrum’s acid in glacial acetic acid at 70 °C. Photophysical studies of these compounds have been reported. Reactions involving cyclohexane-1,3-dione/5-methylcyclohexane-1,3-dione/dimedone in the place of Meldrum’s acid yielded corresponding benzo[a]chromeno[2,3-c]phenazine derivatives. Crystal structure of 3k established the regioisomer formed. Mild reaction conditions, good yields, short reaction time, and easy separation are some of the salient features of the present protocol. 相似文献
96.
Jagjeet Kaur Deepti Singh Vikas Dubey N. S. Suryanarayana Yogita Parganiha Pooja Jha 《Research on Chemical Intermediates》2014,40(8):2737-2771
In this review different methods of preparing lanthanum aluminate (LaAlO3) phosphors are discussed. The molten salt method, the combustion method, the sucrose method, and the coprecipitation technique are the best methods for preparing LaAlO3 phosphors with small particle size and high surface area by low-temperature synthesis. LaAlO3 usually has a rhombohedral structure. It has good dielectric properties and, hence, is regarded as an attractive alternative to SiO2 in microelectronic devices. LaAlO3 phosphors have excellent chemical and thermal stability, mechanical durability, and exploitable optical and electronic properties, leading to a wide range of potential applications. LaAlO3 phosphors doped with rare-earth ions have luminescence properties and can, hence, be used in optical display systems. 相似文献
97.
Oxidation of 2-aryl-2,3-dihydro-4(1H)-quinolones (1) with 1.5 equivalents of (dichloroiodo)benzene in dichloromethane at room temperature leads to regioselective chlorination, thereby offering an efficient method for the synthesis of new 2-aryl-6-chloro-2,3-dihydro-4(1H)-quinolones (3). 相似文献
98.
Silymarin,a polyphenolic flavonoid impede Plasmodium falciparum growth through interaction with heme
Pooja Rani Mina Yogesh Kumar Ajeet Kumar Verma Feroz Khan Sudeep Tandon Anirban Pal 《Natural product research》2020,34(18):2647-2651
AbstractA polyphenolic flavonoid, Silymarin isolated from Silybum marianum is widely known for its hepatoprotective action. In the present study anti-plasmodial activity of Silymarin has been demonstrated for the first time having IC50 of 14?±?0.33?μM against the NF-54 strain of P. falciparum with high selectivity index (>100). The parasitostatic action is exerted through inhibition of β-hematin/hemozoin formation which is due to the interaction (Kd?=?3.63?±?0.9µM) of silymarin with free heme in a Stoichiometry of 1:1 Silymarin: heme complex resulting into heme-induced membrane damage in the parasite. Silymarin could hinder the glutathione and hydrogen peroxide-induced heme detoxification. Silymarin also induces apoptosis in the parasite through the elevation of caspase-3 level in a dose-dependent manner. Results from the docking studies suggest that Silymarin interacts with heme. 相似文献
99.
100.
The solution and solid state conformations of a designed β-hairpin containing functionalizable α,β-unsaturated γ-amino acids at the antiparallel β-strands and a single step transformation to its saturated γ-peptide analogue are studied. 相似文献