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91.
Sohei Okazaki Yasushi Hirose Taro Hitosugi Toshihiro Shimada Tetsuya Hasegawa 《Applied Surface Science》2007,254(3):757-759
We propose a novel method for high-throughput quantitative analysis of thin-film conductivity σ by using a scanning microwave microscope (SμM). We demonstrated that composition spread thin films of Ti1-xNbxO2 can be utilized as a standard reference in a wide σ range. The shift in Q-value measured by SμM along the composition-spread axis showed a single peak, which moved to the lower x side with film thickness. This behavior was confirmed by electrical field simulation using the finite element method. 相似文献
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Mg-promoted reduction of benzophenones in the presence of ethyl trifluoroacetate and trimethylchlorosilane in N-methyl-2-pyrrolidinone afforded the corresponding cross-coupling products, which were easily transformed into C-trifluoroacetylated compounds of benzophenones through desilylation by tetrabutylammonium fluoride. 相似文献
96.
Guijun Ma Yohichi Suzuki Rupashree Balia Singh Aki Iwanaga Yosuke Moriya Tsutomu Minegishi Jingyuan Liu Takashi Hisatomi Hiroshi Nishiyama Masao Katayama Kazuhiko Seki Akihiro Furube Taro Yamada Kazunari Domen 《Chemical science》2015,6(8):4513-4518
The particulate semiconductor La5Ti2CuS5O7 (LTC) with a band gap energy of 1.9 eV functioned as either a photocathode or a photoanode when embedded onto Au or Ti metal layers, respectively. By applying an LTC/Au photocathode and LTC/Ti photoanode to, respectively, photoelectrochemical (PEC) water reduction and oxidation concurrently, zero-bias overall water splitting was accomplished under visible light irradiation. The band structures of LTC/Au and LTC/Ti calculated using a semiconductor device simulator (AFORS-HET) confirmed the critical role of the solid/solid junction of the metal back contact in the charge separation and PEC properties of LTC photoelectrodes. The prominently long lifetime of photoexcited charge carriers in LTC, confirmed by transient absorption spectroscopy, allowed the utilization of both photoexcited electrons and holes depending on the band structure at the solid/solid junction. 相似文献
97.
Tajiri S Kanamaru T Yoshida K Hosoi Y Konno T Yada S Nakagami H 《Chemical & pharmaceutical bulletin》2010,58(10):1295-1300
After the dosing of an extended-release (ER) formulation, compounds may exist in solutions at various concentrations in the colon because the drugs are released at various speeds from the ER dosage form. The aim of this study was to investigate the relationship between the drug concentration profiles in plasma and the drug doses in the colon. Several drug solutions of different concentrations were directly administered into the ascending colon of dogs using a lubricated endoscope, and the effects of the drug dose on colonic absorption were estimated. As a result, dose-dependency of colonic absorption varied from compound to compound. Although the relative bioavailability of colonic administration of diclofenac, metformin and cevimeline compared to oral administration was similar regardless of the drug doses in the colon, colonic absorption of diltiazem varied according to the doses. From the results of the co-administration of verapamil and fexofenadine, it was clear that diltiazem underwent extensive hepatic and gastrointestinal first-pass metabolism, resulting in a low area under the curves (AUC) at a low drug dose. During the design of oral ER delivery systems, a colonic absorption study of candidate compounds should be carried out at several solutions of different drug concentrations and assessed carefully. 相似文献
98.
Ji‐Ho Yoon Prof. Yun‐Je Lee Jeasung Park Dr. Taro Kawamura Dr. Yoshitaka Yamamoto Dr. Takeshi Komai Dr. Satoshi Takeya Dr. Sang Sup Han Dr. Jong‐Won Lee Prof. Yongjae Lee Prof. 《Chemphyschem》2009,10(2):352-355
Easy come, easy go: Hydroquinone forms a channel structure of cages with hydrogen‐bonded hexagons. These may provide an ideal route for the fast inclusion and facile release of hydrogen molecules (see figure), which can lead to reversible hydrogen storage under mild conditions.
99.
Matsuo E Toda C Watanabe M Iida T Masuda T Minohata T Ando E Tsunasawa S Nishimura O 《Rapid communications in mass spectrometry : RCM》2006,20(1):31-38
We have developed the NBS (2-nitrobenzenesulfenyl) method, a quantitative proteome analysis method utilizing stable isotope labeling followed by mass spectrometry. The potential of this method was reported previously, and the procedure has now been further optimized. Here, we describe a procedure utilizing urea or guanidine hydrochloride as a protein denaturant, in conjunction with an improved chromatographic enrichment method for the NBS-labeled peptides using a phenyl resin column. By using this new protocol, both sample loss throughout the protocol and the elution of unwanted unlabeled peptides can be minimized, improving the efficiency of the analysis significantly. 相似文献
100.
Udagawa T Ishimoto T Tokiwa H Tachikawa M Nagashima U 《The journal of physical chemistry. A》2006,110(22):7279-7285
The geometric isotope effect (GIE) of sp- (acetylene-water), sp(2)- (ethylene-water), and sp(3)- (methane-water) hybridized intermolecular C-H...O and C-D...O hydrogen bonds has been analyzed at the HF/6-31++G level by using the multicomponent molecular orbital method, which directly takes account of the quantum effect of proton/deuteron. In the acetylene-water case, the elongation of C-H length due to the formation of the hydrogen bond is found to be greater than that of C-D. In contrast to sp-type, the contraction of C-H length in methane-water is smaller than that of C-D. After the formation of hydrogen bonds, the C-H length itself in all complexes is longer than C-D and the H...O distance is shorter than D...O, similar to the GIE of conventional hydrogen bonds. Furthermore, the exponent (alpha) value is decreased with the formation of the hydrogen bond, which indicates the stabilization of intermolecular C-H...O hydrogen bonds as well as conventional hydrogen bonds. In addition, the geometric difference induced by the H/D isotope effect of the intramolecular C-H...O hydrogen bond shows the same tendency as that of intermolecular C-H...O. Our study clearly demonstrates that C-H...O hydrogen bonds can be categorized as typical hydrogen bonds from the viewpoint of GIE, irrespective of the hybridizing state of carbon and inter- or intramolecular hydrogen bond. 相似文献