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991.
Penumaka Nagababu Mynam Shilpa Sirasani Satyanarayana Jeevigunta Naveena Lavanya Latha Kilampalli Shivaramasastri Karthikeyan Medisetti Rajesh 《Transition Metal Chemistry》2008,33(8):1027-1033
Four asymmetric cobalt(III) complexes, [Co(bpy)2(aip)]3+, [Co(bpy)2(pyip)]3+, [Co(phen)2(aip)]3+, and [Co(phen)2(pyip)]3+ (bpy = 2,2,bipyridine, phen = 1,10-phenathroline), (pyip = 2-(1-pyrenyl)-1H-imidazo[4,5-f][phen], (aip = 2-(9-anthryl)-1H-imidazo[4,5,-f][phen],
have been synthesized and characterized. Their interaction with calf thymus DNA (CT-DNA) was investigated by physico-chemical
methods and photocleavage. The size and shape of the ligands have a marked effect on the DNA-binding affinity of the complexes.
Irradiation of pBR322 DNA with these novel cobalt(III) complexes results in nicking of the plasmid DNA. Toxicity and induced
cell death investigations revealed that the complexes of pyip had higher toxicity than those of aip.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
This tutorial review provides an overview of bio-directed synthesis of nanomaterials, starting with the foundation of biomineralization research--how organisms are able to biomineralize materials in vivo--and progressing to studies of biomineralization in vitro. This research is of interest to biologists, chemists and materials scientists alike, especially in light of efforts to find 'greener' methods of inorganic material synthesis. Examples of applications of nanomaterials synthesized by these methods are provided to demonstrate the end goals of biomineralization research. 相似文献
993.
Leys J Wübbenhorst M Preethy Menon C Rajesh R Thoen J Glorieux C Nockemann P Thijs B Binnemans K Longuemart S 《The Journal of chemical physics》2008,128(6):064509
The electrical conductivities of 1-alkyl-3-methylimidazolium tetrafluoroborate ionic liquids and of 1-hexyl-3-methylimidazolium ionic liquids with different anions were determined in the temperature range between 123 and 393 K on the basis of dielectric measurements in the frequency range from 1 to 10(7) Hz. Most of the ionic liquids form a glass and the conductivity values obey the Vogel-Fulcher-Tammann equation. The glass transition temperatures are increasing with increasing length of the alkyl chain. The fragility is weakly dependent on the alkyl chain length but is highly sensitive to the structure of the anion. 相似文献
994.
Andhariya N Chudasama B Patel R Upadhyay RV Mehta RV 《Journal of colloid and interface science》2008,323(1):153-157
In the present investigation we report the effect of capillary diameter and the direction of applied magnetic field on the rotational viscosity of water and kerosene based ferrofluids. We found that changes in the field induced rotational viscosity are larger in the case of water based magnetic fluid than that of kerosene based fluid. The field induced rotational viscosity is found to be inversely proportional to the capillary diameter and it falls exponentially as a function of the angle between the direction of field and vorticity of flow. Magnetophoretic mobility and hydrodynamic volume fraction of nanomagnetic particles are determined for above cases. 相似文献
995.
Pandey RK Wang L Wallock NJ Lindeman S Donaldson WA 《The Journal of organic chemistry》2008,73(18):7236-7245
The reactivity of (2-alkenyl-3-pentene-1,5-diyl)iron complexes toward olefin metathesis, cycloaddition, and mild oxidations (MnO 2 or mCPBA) was examined. Cycloaddition reactions were observed to occur with modest diastereoselectivity (33-63% de). Decomplexation of the (3-pentenediyl) ligand may be accomplished by oxidation with either CAN or alkaline hydrogen peroxide to afford vinylcyclopropanecarboxylates or divinylcyclopropanecarboxylates. Reduction of the latter, followed by Cope rearrangement generates cycloheptadienylmethanols. These studies demonstrate that (2-alkenyl-3-pentene-1,5-diyl)iron complexes can serve as organometallic scaffolds for the preparation of a wide variety of structural motifs containing up to 5 contiguous stereocenters. 相似文献
996.
The first application of Baylis-Hillman adducts in the synthesis of azetidines is reported. The synthesis involves a one-pot, high yielding and highly diastereoselective annulation of unmodified Baylis-Hillman adducts with N-arylphosphoramidates to afford 1,2-disubstituted azetidine-3-carbonitriles/carboxylates, which are the precursors of biologically versatile azetidine-3-carboxylic acids. 相似文献
997.
Viksit Kumar H. J. Bharathkumar Sangram D. Dongre Rajesh Gonnade Kothandam Krishnamoorthy Sukumaran Santhosh Babu 《Angewandte Chemie (International ed. in English)》2023,62(47):e202311657
Recently, chiral and nonplanar cutouts of graphene have been the favorites due to their unique optical, electronic, and redox properties and high solubility compared with their planar counterparts. Despite the remarkable progress in helicenes, π-extended heterohelicenes have not been widely explored. As an anode in a lithium-ion battery, the racemic mixture of π-extended double heterohelical nanographene containing thienothiophene core exhibited a high lithium storage capability, attaining a specific capacity of 424 mAh g−1 at 0.1 A g−1 with excellent rate capability and superior long-term cycling performance over 6000 cycles with negligible fade. As a first report, the π-extended helicene isomer (PP and MM), with the more interlayer distance that helps faster diffusion of ions, has exhibited a high capacity of 300 mAh g−1 at 2 A g−1 with long-term cycling performance over 1500 cycles compared to the less performing MP and PM isomer and racemic mixture (150 mAh g−1 at 2 A g−1). As supported by single-crystal X-ray analysis, a unique molecular design of nanographenes with a fixed (helical) molecular geometry, avoiding restacking of the layers, renders better performance as an anode in lithium-ion batteries. Interestingly, the recycled nanographene anode material displayed comparable performance. 相似文献
998.
Shaifali Mishra Rajesh K. Yadav Satyam Singh Surabhi Chaubey Pooja Singh Chandani Singh Sarvesh Kumar Gupta Shivani Gupta Dhanesh Tiwary Tae Wu Kim 《Photochemistry and photobiology》2023,99(4):1080-1091
Photocatalysis is a defendable manner for production of several organic chemicals, energy and its storage from solar energy. For the evolution of metal free, cost-effective catalyst a 2D composite has been appear as a photocatalyst. Here, we had reported the synthesis of a light harvesting composite as a photocatalyst which was assembled by a poly-condensation mechanism between graphitic carbon nitride and tetrakis(4-nitrophenyl) porphyrin and the resulting composite manifest the excellent light harvesting properties, suitable energy band and low charge recombination. The photocatalyst [(NO2)4TPP@g-C3N4] enables the efficient photocatalytic production of nicotinamide adenine dinucleotide (NADH) from consumed NAD+ also the production of organic chemicals like 4-methoxybenzylimines from 4-methoxybenzylamines. The photocatalytic efficiency of the photocatalyst was estimated by the percentage of NADH regeneration and the percentage yield of organic transformations. It shows the tetrakis(4-nitrophenyl) porphyrin could enhance the charge transfer capacity of graphitic carbon nitride which shows excellent photocatalysis activities and organic transformations. 相似文献
999.
Zhichun Bao Delin Lai Pengchang Shen Mengxin Yu Rajesh Kumar Yancheng Liu Zhenfeng Chen Hong Liang 《无机化学与普通化学杂志》2019,645(6-7):570-579
A novel SmIII complex [SmIII(LA)2(pic)3] (Hpic = picric acid), in which LA is a natural‐derived alkaloid, liriodenine, was synthesized and characterized by IR, elemental analysis, and single‐crystal X‐ray diffraction analysis. This complex showed enhanced solubility compared with liriodenine and its metal complexes that have been previously reported. The interaction of the SmIII complex with ct‐DNA was further investigated by various spectroscopic techniques, such as UV/Vis spectroscopy, fluorescence spectroscopy, circular dichroism spectroscopy (CD), and viscosity measurement. The results showed that the intrinsic binding constant Kb of the SmIII complex with ct‐DNA was calculated to be 5.03 × 103 L·mol–1 by UV/Vis absorption spectral analysis. The thermodynamic fluorescent spectral analysis suggested that the fluorescence intensity of the SmIII complex was weakened by ct‐DNA mainly through a dynamic quenching mechanism. The presence of Sm complex could increase the viscosity of DNA solution, so it was concluded that the complex bound with ct‐DNA via a moderate intercalative mode. Furthermore, this SmIII complex exhibited significant growth inhibition on the three typical tumor cell lines, HepG2, T‐24, and SK‐OV‐3, with the corresponding IC50 values, 10.76 ± 0.19, 8.85 ± 1.12, and 10.01 ± 0.55 μM, respectively. The in vitro antitumor activity was comparable with LA and cisplatin, which suggested that it might be a new broad spectrum antitumor agent with more satisfying solubility. 相似文献
1000.
A facile one‐pot synthesis of N‐fused 1,2,4‐triazoles from heterocyclic hydrazines and aldehydes is reported. The reaction is efficiently promoted by trichloroisocyanuric acid to afford the desired products mostly in high yields and in relatively short time. The mild nature of the synthesis and short reaction time are notable advantages of the developed protocol. This protocol is effective toward various substrates having different functionalities. 相似文献