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排序方式: 共有266条查询结果,搜索用时 187 毫秒
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Philip N. Dubbin Stephen H. Cody David A. Williams 《Micron (Oxford, England : 1993)》1993,24(6):581-586
Using the pH-sensitive dual-emission fluorophore, carboxy-seminaphthorhodaflour-1 (SNARF-1) coupled with a laser-scanning confocal microscope system it is now possible to map intracellular pH. We have applied this combination to investigate the pH levels and distribution within single isolated cultured proximal tubule, bovine aortic endothelial and rat aortic smooth muscle cells. The majority of cells showed a uniform cytosolic pH. However, pH gradients were evident between the cytosol and nuclear regions with the nuclear regions having a predominantly higher pH than the cytosol. High concentrations of nigericin removed this gradient and indicated that active control of intranuclear pH by the nuclear membrane occured, possibly via the K+/H+ exchangers. 相似文献
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U. Sudarsan N. W. Cody T. Dosluoglu R. Solanki 《Applied Physics A: Materials Science & Processing》1990,50(3):325-330
An ArF excimer laser has been used to achieve homoepitaxy of GaP at 500° C using trimethylgallium and tertiarybutylphosphine as the precursor gases. Dependence of epitaxial growth on several parameters is examined. The crystalline properties of the films are determined using cross-sectional transmission electron microscopy. It is found that at 500° C, in the presence of laser radiation, higher growth rate and superior crystalline properties of GaP are achieved compared to purely thermal metalorganic vapor phase epitaxy under the same conditions. Electrical properties of p-n diodes fabricated via Zn doping have also been examined. 相似文献
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Dr. Benjamin A. Chalmers Hui Xing Sevan Houston Dr. Charlotte Clark Dr. Sussan Ghassabian Dr. Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Dr. Jeanette E. Stok Dr. Glen M. Boyle Carly J. Pierce Stuart W. Littler Prof. David A. Winkler Prof. Paul V. Bernhardt Dr. Cielo Pasay Prof. James J. De Voss Prof. James McCarthy Prof. Peter G. Parsons Prof. Gimme H. Walter Prof. Maree T. Smith Prof. Helen M. Cooper Prof. Susan K. Nilsson Dr. John Tsanaktsidis Dr. G. Paul Savage Prof. Craig M. Williams 《Angewandte Chemie (International ed. in English)》2016,55(11):3580-3585
Pharmaceutical and agrochemical discovery programs are under considerable pressure to meet increasing global demand and thus require constant innovation. Classical hydrocarbon scaffolds have long assisted in bringing new molecules to the market place, but an obvious omission is that of the Platonic solid cubane. Eaton, however, suggested that this molecule has the potential to act as a benzene bioisostere. Herein, we report the validation of Eaton's hypothesis with cubane derivatives of five molecules that are used clinically or as agrochemicals. Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues displayed equal bioactivity, and the fifth one demonstrated only partial efficacy. Ramifications from this study are best realized by reflecting on the number of bioactive molecules that contain a benzene ring. Substitution with the cubane scaffold where possible could revitalize these systems, and thus expedite much needed lead candidate identification. 相似文献
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Lafond A Cody JA Souilah M Guillot-Deudon C Kiebach R Bensch W 《Inorganic chemistry》2007,46(4):1502-1506
The study of the pseudobinary system Cu(2)SnS(3-)Cu(2)SiS(3) shows that a solid solution (Cu(2)Si(x)Sn(1-x)S(3)) exists in the range 0.4 < or = Si/(Sn+Si) < or = 0.6. Based on diffuse reflectance and photoelectrochemical measurements these compounds show potential as absorber materials for photovoltaic devices. The compounds were prepared at 850 degrees C from copper sulfide, silicon, tin, and sulfur and were analyzed with single-crystal (for x approximately 0.40) and powder diffraction techniques. Optical band gaps of 1.25, 1.35, and 1.45 eV were observed for the three compositions x = 0.39, 0.48, and 0.61; cathodic photocurrent occurring is significant. 相似文献
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Dr. Phil Liebing Dr. Cody Ross Pitts Marc Reimann Dr. Nils Trapp Dr. David Rombach Dustin Bornemann Prof. Dr. Martin Kaupp Prof. Dr. Antonio Togni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):6086-6093
The analysis of crystal structures of SF5- or SF4-containing molecules revealed that these groups are often surrounded by hydrogen or other fluorine atoms. Even though fluorine prefers F⋅⋅⋅H over F⋅⋅⋅F contacts, the latter appeared to be important in many compounds. In a significant number of datasets, the closest F⋅⋅⋅F contacts are below 95 % of the van der Waals distance of two F atoms. Moreover, a number of repeating structural motifs formed by contacts between SF5 groups was identified, including different supramolecular dimers and infinite chains. Among SF4-containing molecules, the study focused on SF4Cl compounds, including the first solid-state structure analyses of these reactive species. Additionally, electrostatic potential surfaces of a series of Ph-SF5 derivatives were calculated, pointing out the substituent influence on the ability of F⋅⋅⋅X contact formation (X=F or other electronegative atom). Interaction energies were calculated for different dimeric arrangements of Ph-SF5, which were extracted from experimental crystal structure determinations. 相似文献