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941.
Dr. Lea Gundorff Nielsen Dr. Anne Katrine Ravnsborg Hansen Dr. Patrycja Stachelek Dr. Robert Pal Prof. Dr. Thomas Just Sørensen 《欧洲无机化学杂志》2023,26(24):e202300245
Since the pioneering report by Selvin, we have been fascinated by the potential of using lanthanide luminescence in bioimaging. The uniquely narrow emission lines and long luminescence lifetimes both provide the potential for background free images together with full certainty of probe localization. General use of lanthanide based bioimaging was first challenged by low brightness, and later by the need of UV (<405 nm) excitation sources not present in commercial microscopes. Here, we designed three lanthanide-based imaging probes based on a known motif to investigate the limitations of 405 nm excitation. These were synthesized, characterized, investigated on dedicated as well as commercial microscopes, and the photophysics was explored in detail. It was proven without doubt that the lanthanide complexes enter the cells and luminesce internally. Even so, no lanthanide luminescence were recovered on the commercial microscopes. Thus, we returned to the photophysical properties that afforded the conclusion that – despite the advances in light sources and photodetectors – we need new designs that can give us brighter lanthanide complexes before bioimaging with lanthanide luminescence becomes something that is readily done. 相似文献
942.
D. Sravanakumar Perumalla Sagar Ghorai Tanmoy Pal Drahomír Hnyk Josef Holub Eluvathingal D. Jemmis 《Journal of computational chemistry》2023,44(3):256-260
Closo-carborane anions are prominent, whereas the cations of the same are less abundant in the literature. As these ions have similar size and are weakly coordinating, the ionic liquids of these two ions could have important applications in many areas of chemistry. In view of limited number of polyhedral carborane cations available, we revisited the rearrangement of dicarboranyl methyl cation (7-CH2 7,9-nido-C2B9H10+) using ab initio molecular dynamics calculations with metadynamics. Our simulations confirmed the concerted mechanism of the rearrangement. We believe this work will resume the interest in its synthesis and carborane cations in general. 相似文献
943.
Studies on direct-current electrical conductivity and optical properties of a new solution of processable conducting polymer
are reported. Electrical conductivity of thin films of the polymer on glass plate at room temperature was 6×10−6 S/cm. Study of conductivity with variation of temperature does not provide any definite thermal activation energy, which
is in accordance with the amorphous nature of polymer. Optical absorption data adopting the Bardeen equation showed that maximum
‘optical gap’ (E
g
) is 3.30 eV. Doping with Br2-vapor was found to be only partially effective in decreasingE
g
by 0.43 eV. The polymer was found to be quite stable under normal atmospheric conditions. Environmental stability of both
undoped and doped polymer has been discussed.
Part 2: [5] 相似文献
944.
A. N. Zhukov N. S. Sidorov A. V. Pal’nichenko V. V. Avdonin D. V. Shakhray 《Journal of Experimental and Theoretical Physics》2010,110(2):275-279
The effect of steplike shock-wave compression up to 65 GPa on the crystal structure and super-conducting transition temperature of a polycrystalline MgB2 sample is studied. X-ray diffraction demonstrates that the shock-wave compression of the MgB2 sample does not cause any irreversible structural phase transformations in it except for the formation of lattice microstrains. These conclusions agree with the super-conducting transition temperatures of the MgB2 sample measured before and after shock-wave compression. 相似文献
945.
Phytochelatins: Peptides Involved in Heavy Metal Detoxification 总被引:3,自引:0,他引:3
Phytochelatins (PCs) are enzymatically synthesized peptides known to involve in heavy metal detoxification and accumulation, which have been measured in plants grown at high heavy metal concentrations, but few studies have examined the response of plants even at lower environmentally relevant metal concentrations. Recently, genes encoding the enzyme PC synthase have been identified in plants and other species enabling molecular biological studies to untangle the mechanisms underlying PC synthesis and its regulation. The present paper embodies review on recent advances in structure of PCs, their biosynthetic regulation, roles in heavy metal detoxification and/or accumulation, and PC synthase gene expression for better understanding of mechanism involved and to improve phytoremediation efficiency of plants for wider application. 相似文献
946.
Towards meso‐Ester BODIPYs with Aggregation‐Induced Emission Properties: The Effect of Substitution Positions
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Ming Hui Chua Dr. Yong Ni Monalisa Garai Dr. Bin Zheng Prof. Kuo‐Wei Huang Prof. Qing‐Hua Xu Dr. Jianwei Xu Prof. Jishan Wu 《化学:亚洲杂志》2015,10(8):1631-1634
Three meso‐ester boron dipyrromethene (BODIPY) dyes have been synthesized and functionalized with aggregation‐induced emission (AIE)‐active tetraphenylethene or triphenylethene moieties. It was found that functionalizing at the different positions of the BODIPY core resulted in the final dye having different emission properties in response to aggregation: from aggregation‐induced quenching (ACQ) to being AIE active. X‐ray crystallographic analysis was thus performed to provide an explanation for these differences. 相似文献
947.
Susobhan Choudhury Subrata Batabyal Dr. Tanumoy Mondol Dilip Sao Peter Lemmens Prof. Dr. Samir Kumar Pal 《化学:亚洲杂志》2014,9(5):1395-1402
Charge migration along DNA molecules is a key factor for DNA‐based devices in optoelectronics and biotechnology. The association of a significant amount of water molecules in DNA‐based materials for the intactness of the DNA structure and their dynamic role in the charge‐transfer (CT) dynamics is less documented in contemporary literature. In the present study, we have used a genomic DNA–cetyltrimethyl ammonium chloride (CTMA) complex, a technological important biomaterial, and Hoechest 33258 (H258), a well‐known DNA minor groove binder, as fluorogenic probe for the dynamic solvation studies. The CT dynamics of CdSe/ZnS quantum dots (QDs; 5.2 nm) embedded in the as‐prepared and swollen biomaterial have also been studied and correlated with that of the timescale of solvation. We have extended our studies on the temperature‐dependent CT dynamics of QDs in a nanoenvironment of an anionic, sodium bis(2‐ethylhexyl)sulfosuccinate reverse micelle (AOT RMs), whereby the number of water molecules and their dynamics can be tuned in a controlled manner. A direct correlation of the dynamics of solvation and that of the CT in the nanoenvironments clearly suggests that the hydration barrier within the Arrhenius framework essentially dictates the charge‐transfer dynamics. 相似文献
948.
Heterogeneously Porous γ‐MnO2‐Catalyzed Direct Oxidative Amination of Benzoxazole through CH Activation in the Presence of O2 下载免费PDF全文
Provas Pal Arnab Kanti Giri Harshvardhan Singh Dr. Subhash Chandra Ghosh Dr. Asit Baran Panda 《化学:亚洲杂志》2014,9(9):2392-2396
Oxidative amination of azoles through catalytic C? H bond activation is a very important reaction due to the presence of 2‐aminoazoles in several biologically active compounds. However, most of the reported methods are performed under homogeneous reaction conditions using excess reagents and additives. Herein, we report the heterogeneous, porous γ‐MnO2‐catalyzed direct amination of benzoxazole with wide range of primary and secondary amines. The amination was carried under mild reaction conditions and using molecular oxygen as a green oxidant, without any additives. The catalyst can easily be separated by filtration and reused several times without a significant loss of its catalytic performance. Of note, the reaction tolerates a functional group such as alcohol, thus indicating the broad applicability of this reaction. 相似文献
949.
950.
TFAA/H3PO4‐Mediated C‐2 Acylation of Thiophene: A Direct Synthesis of Known and Novel Thiophene Derivatives of Pharmacological Interest 下载免费PDF全文
P. Bindu Shravan Reddy Naini K. Shanmukha Rao P. K. Dubey Sarbani Pal 《Journal of heterocyclic chemistry》2014,51(3):586-593
A number of aliphatic and aromatic carboxylic acids were reacted with thiophene in the presence of trifluoroacetic anhydride and H3PO4 to give a variety of acylated thiophenes in good to excellent yields. The methodology was used to prepare known nonsteroidal anti‐inflammatory drug‐based novel compounds of potential pharmacological significances. Molecular modeling studies were carried out by using nonsteroidal anti‐inflammatory drug‐based thiophene derivatives to assess their cyclooxygenase inhibiting potential in silico. On the basis of docking studies followed by subsequent in vitro assay, indomethacin‐based thiophene derivative was identified as a novel cyclooxygenase‐2 inhibitor with balanced selectivity. 相似文献