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91.
Journal of Solid State Electrochemistry - A novel electrochemical profiling technique consisting in integration capacitance–voltage characteristics was proposed, developed and proven. The aim... 相似文献
92.
93.
Carolin Blum Lothar Opilik Joanna M. Atkin Kai Braun Stefan B. Kmmer Vasily Kravtsov Naresh Kumar Sergey Lemeshko Jian‐Feng Li Karol Luszcz Teimour Maleki Alfred J. Meixner Steve Minne Markus B. Raschke Bin Ren Jan Rogalski Debdulal Roy Bruno Stephanidis Xiang Wang Dai Zhang Jin‐Hui Zhong Renato Zenobi 《Journal of Raman spectroscopy : JRS》2014,45(1):22-31
Since its first experimental realization, tip‐enhanced Raman spectroscopy (TERS) has emerged as a potentially powerful nanochemical analysis tool. However, questions about the comparability and reproducibility of TERS data have emerged. This interlaboratory comparison study addresses these issues by bringing together different TERS groups to perform TERS measurements on nominally identical samples. Based on the spectra obtained, the absolute and relative peak positions, number of bands, peak intensity ratios, and comparability to reference Raman and surface‐enhanced Raman spectroscopy (SERS) data are discussed. Our general findings are that all research groups obtained similar spectral patterns, irrespective of the setup or tip that was used. The TERS (and SERS) spectra consistently showed fewer bands than the conventional Raman spectrum. When comparing these three methods, the spectral pattern match and substance identification is readily possible. Absolute and relative peak positions of the three major signals of thiophenol scattered by 19 and 9 cm−1, respectively, which can probably be attributed to different spectrometer calibrations. However, within the same group (but between different tips), the signals only scattered by 3 cm−1 on average. This study demonstrated the suitability of TERS as an analytical tool and brings TERS a big step forward to becoming a routine technique. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
94.
Valery P. Nesterenko Vasily P. Glybin Ludmila K. Svirko 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract By combination of the ionexchange and ionic-molecular layering methods [1], the synthesis of natural zeolite derivatives (clinoptilolite) containing in its composition nano-size fragments of Ti(IV) and Zr(IV) phosphates was performed. It was determined by the X-Ray method, that the phosphates of Ti(IV) and Zr(IV) replicate crystal lattice of zeolite, manifesting in enhancing the line's intensity on X-Ray patterns. The Brensted's and Lewis's spectra of acidic centers distributions were obtained by Hammett's indicator spectrophotometric method [2] in the interval of pK, values from -4.4 to 14.2, which have shown that P(V) of the derivatives is represented mainly by HPO4- and H2PO4-groups, with predomination of these latter. It is shown that the force of Brensted's acidic centers, influenced by H2PO4-groups. remains at the level of H2PO(aq)-anion, and the force of the centers due to HPO4-groups shifts into alkaline region, about 0,5 unit of pK. The strong acidic Lewis's centers were detected at the levels of pK, from 0 to -4.0. The spectra of Ti(IV) and Zr(IV) phosphates is presented in (1) and (2) respectively. A set of the acquired results makes possible a suggestion about using P(V)-containing derivatives in processes which are catalyzed both with Brensted's and Lewis's centers participation. 相似文献
95.
Leonid Lynkov Vasily Glybin Tamara Selivyorstova Vadim Bogush 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Cellulosic fibres present great interest as matrix for non-organic synthesis with the use of ion-molecular layering method [I]. This method consists in realization of the successive reactions with the surface functional groups. Synthesized materials can he of scientific and technical interest. 相似文献
96.
Ion Neda Vasily A. Pinchuk Holger Thnnessen Ludger Ernst Peter G. Jones Reinhurd Schmutzler 《无机化学与普通化学杂志》1997,623(8):1325-1332
The reaction of (chloromethyl)dichlorophosphine 1 with N,N′-dimethyl-N,N′-bis(trimethylsilyl)urea 2 furnished the σ5P-σ3P-diphosphorus compound 3 . The reaction of 3 with hexafluoroacetone proceeded in an unusual fashion, with the rupture of the P? P bond, resulting in 4,4-bis(trifluoromethyl)-3-chloro-2-hexfluoroisopropoxy-2-oxo-1,2-oxaphosphetane 7 and the spirophosphorane 4-chloromethyl-1,3,5,7-tetramethyl-1,3,5,7-tetraaza-4σ5-phosphaspiro-[3,3]heptan-2,6-dione 8 . The reaction of 2-chloro-1,2-dimethyl-3-phenyl-2-phenylseleno-1,3,2σ5-diazaphosphetidin-4-one 9 with bis(2-chloroethyl)amine hydrochloride/triethylamine 10 also proceeded in an unexpected fashion, leading to the spirophosphorane 11 as the only identified product. Single-crystal X-ray structure analyses of compounds 8 and 11 were conducted. The coordination geometry at phosphorus in both compounds shows a large deviation from idealized forms. This distortion arises mainly from the presence of the four-membered rings. 相似文献
97.
M. Yu. Lavrentiev H. Köppel L. S. Cederbaum 《Zeitschrift für Physik B Condensed Matter》1993,91(4):481-492
A one-dimensional system is investigated which consists of monomers with Jahn-Teller-active vibrational coordinates. Peierls distortions in the ground states of the half- and quarter-filled systems are studied as a function of the electron-lattice and Jahn-Teller coupling constants. For both degrees of filling and for all the values of the coupling constants the band structure of the ground state is doubly degenerate. The interrelation is discussed between the present system and systems where the active internal degrees of freedom are not of the Jahn-Teller type. 相似文献
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99.