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41.
The Sanita-kun Coliforms consists of a transparent cover film, an adhesive sheet, a layer of nonwoven fabric, and a water-soluble compound film, including a culture medium formula for the detection of coliforms. The medium sheet was validated with 26 food types belonging to 9 food categories (meat, poultry, fish and seafood, fruits and vegetable, dairy, chocolate or bakery, animal feeds, pasta, and miscellaneous) using violet red bile (VRB) agar method in the U.S. Food and Drug Administration's Bacteriological Analytical Manual as a reference according to the AOAC guideline. The medium sheet showed 100% inclusivity and exclusivity. Ruggedness study suggested allowances in the incubation temperature and time as 33-35 degrees C and 24 +/- 4 h, respectively. The performance of 3 different lots of the medium sheets was equivalent and suggested no change of the performance at least for 3 years. In the comparative recovery study, many samples (84.6%), which were inoculated with a coliform strain, showed no significant difference between the 2 methods. The linear correlation coefficient (r2) to the VRB agar was calculated as 0.94. In the repeatability study, the average relative standard deviation of total foods was 0.10 in the medium sheet. In the independent study, the medium sheet detected significantly more colonies than VRB plates in the frozen raw milk sample, while there was no significant difference between the 2 methods in raw ground beef sample. Comparative recovery study on foods, inoculated and then frozen, showed the medium sheet detected injured cells with better recovery than VRB agar. The analysts in the independent study wrote that the medium sheet was easy to use and read overall. The Sanita-kun sheet provides an alternative method to coliform count agar. 相似文献
42.
43.
We predict the elastic properties of mixed amphiphilic monolayers in the swollen state within the blob model using scaling
arguments. First the elastic moduli and the spontaneous curvature of a bimodal brush are determined as a function of the composition
and the relative chain length. We obtain simple and useful scaling functions which interpolate between the elastic moduli
of a pure short-chain brush and a pure long-chain brush. By using the analogy between block copolymer interfaces and polymeric
brushes, the effect of mixing on self-assembled diblock copolymer monolayers is investigated in the swollen state. We calculate
various interfacial properties, such as the equilibrium surface coverage, interface curvature, and the mixing free energy
as a function of the composition. In general, we find a nonlinear dependence on the composition, which deviates from the simple
linear averaging of the properties of pure components. Our results are used to discuss a recent experiment on the effect of
amphiphilic block copolymers on the efficiency of microemulsions.
Received 29 December 2000 and Received in final form 19 March 2001 相似文献
44.
Naoki Yasuda Shigeyuki Yamamoto Yuji Wada Shozo Yanagida 《Journal of polymer science. Part A, Polymer chemistry》2001,39(24):4196-4205
Photochemical reactions of aromatic azide groups were applied for a novel photosensitive silicone ladder polymer, that is, partially vinyl‐substituted polyphenylsilsesquioxane sensitized with aromatic bisazide compounds as a photocrosslinker. The photocrosslinking reaction in this system was investigated from the viewpoint of the efficiency of the photocrosslinker, that is, the ratio of the photocrosslinker consumed for crosslinking. The numbers of photodecomposed azide groups and crosslinks in the polymer were determined by Fourier transform infrared measurements. At a higher bisazide concentration, the predominant reaction of nitrenes formed as the intermediary radical by the photolysis of azide was a coupling reaction that could not contribute to the gelation of the polymer. The ratio of the bisazide compound consumed for crosslinking showed the highest value at its concentration of 3 wt % and decreased with the addition of a larger amount. The semiempirical molecular orbital calculations were applied to the theoretical analysis of the photoreaction of nitrenes using phenylnitrene as a model structure. The calculation results indicated that the coupling reaction of nitrenes should proceed more easily than the photocrosslinking reaction in N2 atmosphere, and the fact that the oxidation of nitrenes should proceed exclusively in the atmosphere including O2 agreed with the experimental results. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4196–4205, 2001 相似文献
45.
Shigeyuki Tasaka Hirokazu Tanabe Yoshiyuki Sasaki Toshiki Machida Mayumi Iino Akira Kiue Seiji Naito Michihiko Kuwano 《Journal of heterocyclic chemistry》1997,34(6):1763-1767
We have investigated 3-substituted-2-phenylimidazo[2,1-b]benzothiazole derivatives and herein we have discussed their pharmaceutical activities. We found that some 2-phenyl-5,6,7,8-tetrahydroimidazo[2,1-b]-benzothiazoles could overcome multidrug resistance for tumor cells. Among them, 2-phenyl-3-(N-methyl-3-piperidyl)carbonylammomiinomemyl-5,6,7,8-tetrahydVoimidazo[2,1-b]benzothiazole [N276-12] demonstrated the most potent activity for overcoming multidrug resistance. 相似文献
46.
Yoshiaki Hidaka Takashi Taniguchi Takashi Kamesawa Hiromitsu Masaoka Koji Inami Hiroyuki Kawano 《国际化学动力学杂志》1993,25(4):305-322
Thermal decomposition of formaldehyde diluted with Ar was studied behind reflected shock waves in the temperature range of 1200–2000 K at total pressures between 1.3 and 3.0 atm. The study was carried out for compositions from the concentrated mixture, 4% CH2O, to the highly dilute mixture, 0.01% CH2O by using time-resolve IR-laser absorption and IR-emission, and a single-pulse technique. From a computer-simulation study, the mechanism and the rate-constant expressions that could explain all of our data and previously reported ARAS data were discussed. This data obtained over a wide concentration range from 50 ppm CH2O to 4% CH2O were satisfactorily modeled by a five-reaction mechanism. © 1993 John Wiley & Sons, Inc. 相似文献
47.
Ikuo Taniguchi Shigeyuki Nakano Tetsuro Nakamura Ahmed El‐Salmawy Masatoshi Miyamoto Yoshiharu Kimura 《Macromolecular bioscience》2002,2(9):447-455
Enzymatic hydrolysis of poly(butylene succinate) (PBS) and poly(butylene succinate‐co‐L ‐lactate) (PBSL) has been studied by using a lipase originated from Pseudomonas cepacia. It has been found that the drawn fibers of PBSL are readily hydrolyzed by the action of the lipase, while those of PBS undergo little enzymatic hydrolysis. Since the polymer films of PBS and PBSL are readily hydrolyzed under the same conditions, the enzymatic hydrolysis should depend not only on the crystallinity but also on the molecular orientation. The molecular weight of the samples gradually decreases with incubation time, because nonspecific hydrolysis occurs on the main chains of both PBS and PBSL even in the absence of lipase. The enzymatic hydrolysis of PBS and PBSL gives 4‐hydroxybutyl succinate (HBS) as the main product with traces of succinic acid and butane‐1,4‐diol together with L ‐lactic acid in the case of PBSL. In addition, the hydrolysis rate of the carboxyl end‐capped PBS is much slower than that of the original or hydroxyl end‐capped PBS. These results imply a hydrolysis mechanism involving the preferential exo‐type chain scission from the carboxyl terminals.
48.
Mikio Hoshino Shiro Konishi Shigeyuki Watanabe Yoshimasa Hama 《Chemical physics letters》1984,110(2):205-208
Optical absorption spectra of one-electron reduced species of copper(II) and oxovanadium(IV) tetraphenylporphyrins. Cu(II)TPP and V(IV)OTPP, in 2-methyltetrahydrofuran at 77 K reveal that not the central metal but the porphyrin ligand is reduced by an excess electron. The triplet ESR spectrum resulting from the spin-spin interaction between two odd electrons located on the porphyrin ligand and the central metal is observed for the one-electron reduced species of V(IV)OTPP while not for that of Cu(II)TPP. 相似文献
49.
Clinical risk prediction formulas for cancer patients can be improved by dynamically updating the formulas by intermediate events, such as tumor progression. The increased accessibility of individual patient data (IPD) from multiple studies has motivated the development of dynamic prediction formulas accounting for between-study heterogeneity. A joint frailty-copula model for overall survival and time to tumor progression has the potential to develop a dynamic prediction formula of death from heterogenous studies. However, the process of developing, validating, and publishing the prediction formula is complex, which has not been sufficiently described in the literature. In this article, we provide a tutorial in order to build a web-based application for dynamic risk prediction for cancer patients on the basis of the R packages joint.Cox and Shiny. We demonstrate the proposed methods using a dataset of breast cancer patients from multiple clinical studies. Following this tutorial, we demonstrate how one can publish web applications available online, which can be manipulated by any user through a smartphone or personal computer. After learning this tutorial, developers acquire the ability to build an online web application using their own datasets. 相似文献
50.
Shuai Zhang Shigeyuki Kuwabara Takahito Suzuki Yoshio Kawano Koji Morita Kenji Fukuda 《Journal of computational physics》2009,228(7):2552-2565
A new basic framework for solid–fluid mixture flow simulation was developed using moving particle methods. The interactions between solid and fluid were modeled by the finite volume particle (FVP) method. The distinct element method (DEM) together with a multi-time-step algorithm was introduced into the FVP method to calculate the effects of contact between solid bodies and between solid bodies and walls. The introduced DEM model was verified by experimental analyses for the collapse of multiple solid cylinder layers. The proposed algorithm using the optimized DEM model was then applied to a water dam breaking, involving multiple solid cylinder layers. A comparison between experiments and simulations demonstrated the DEM model introduced into the FVP method is effective in representing solid–fluid mixture flows reasonably well. 相似文献