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321.
The Blue Obelisk-interoperability in chemical informatics 总被引:1,自引:0,他引:1
Guha R Howard MT Hutchison GR Murray-Rust P Rzepa H Steinbeck C Wegner J Willighagen EL 《Journal of chemical information and modeling》2006,46(3):991-998
The Blue Obelisk Movement (http://www.blueobelisk.org/) is the name used by a diverse Internet group promoting reusable chemistry via open source software development, consistent and complimentary chemoinformatics research, open data, and open standards. We outline recent examples of cooperation in the Blue Obelisk group: a shared dictionary of algorithms and implementations in chemoinformatics algorithms drawing from our various software projects; a shared repository of chemoinformatics data including elemental properties, atomic radii, isotopes, atom typing rules, and so forth; and Web services for the platform-independent use of chemoinformatics programs. 相似文献
322.
We demonstrate a new class of passively temperature stabilized resonant silicon electro-optic modulators. The modulators consist of a ring resonator coupled to a Mach-Zehnder interferometer with tailored thermal properties. We demonstrate 2 GHz continuous modulation over a temperature range of 35 °C and describe the scalability and design rules for such a device. 相似文献
323.
Chayanika Kashyap Siddhartha K. Purkayastha Shahnaz S. Rohman Dr. Ankur K. Guha 《Chemphyschem》2023,24(5):e202200504
The scope of Bergman cyclization is expanded computationally by exploring the cyclization in inorganic B, N substituted derivative. This substitution has introduced polarity into the transition state, which resulted in dramatic lowering of the activation barrier. Natural charge distribution throughout the reaction profile has ascertained this hypothesis. Single B and N atom substitution at 1 and 6 terminal positions lowers the activation barrier by almost half of the original value which becomes even lower in the complete B, N analogue. The parent Bergman and single B, N substituted products were characterized by significant biradical character while the complete B, N substituted analogue was characterized by significant zwitterionic character. Reduction in electron delocalization is also observed in the complete B, N substituted analogue. 相似文献
324.
Namrata Gohain Abhik Bordoloi Amlan J. Kalita Dr. Ankur K. Guha 《Chemphyschem》2023,24(18):e202300581
We report a global planar star-like cluster B3Li3 featuring three planar tetracoordinate boron centres with a rare spin avoided σ-σ diradical character. The cluster was found to be stable towards dissociation into different fragments. The spin density was found to be localized solely on the three boron atoms in the molecular plane. This spin avoided σ-σ diradical character leads to the extension of the coordination number to yield a neutral B3Li3H3 and a cationic B3Li3H3+ cluster with three planar pentacoordinate boron centres in their global minimum structures. The planar geometry of the aninonic B3Li3H3− cluster is slightly higher in energy. The planar global clusters were found to maintain planarity in their ligand protected benzene bound complexes, B3Li3(Bz)3, B3Li3H3(Bz)3 and B3Li3H3(Bz)3+ with high ligand dissociation energies offering candidature for experimental detection. 相似文献
325.
Pooja Jaiswal Prerna Yogeshwar Dr. Koushik Guha Biswas Dr. Debashis Panda 《Chemphyschem》2023,24(14):e202300026
Substrate-assisted product desorption often proposed in heterogeneous catalysis (nanozymes) denounces the catalytic deactivation of these catalysts. On the contrary, the catalytic deactivation of rigid heterogeneous catalyst becomes noticeable in a continuous flow reactor. Surprisingly, it has been addressed inadequately and in an isolated manner. In this study, we have developed a cost-effective non-lithographic method for the fabrication of a PDMS-based microchannel-coupled-millreactor. Immobilized nickel particles are resistant to leaching in the flow process. During continuous operation, millireactors show a strong catalytic activity for reduction of resazurin and p-nitrophenol with a conversion rate of almost 100 %. Catalytic poisoning is ubiquitous and gets gradually prominent whereas complete catalytic deactivation of magnetic Ni-microparticles is found to be an instantaneous process. Relatively large-sized resorufin binds predominantly to the surface and thereby blocks the access of the substrate to the Ni-particles. The dissociations of product molecules - resorufin and p-aminophenol are the rate-limiting steps that caused the abrupt deactivation of Ni-microparticle. The kinetic mechanism of heterogeneous derived from the Langmuir-Hinshelwood mechanism satisfactorily explains the catalytic poisoning and deactivation of nickel microparticles. This study sheds light on the intricacies of catalytic activity and poisoning of magnetic nickel microparticles. 相似文献