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191.
It is very important to predict the radiated noise from the engine intake system for the effective noise control and virtual prototyping of in-cavity and outdoor noise of a vehicle. To this end, one should precisely measure the in-duct acoustic source parameters of the intake system, viz., source strength and source impedance. Usually, the noise radiation characteristics need to be expressed as a function of engine speed. In this study, acoustic source parameters of an engine intake system under engine run-up condition were measured by using the direct method. Direct method employed two external loudspeakers, turned on simultaneously, and three microphones for the separation of upstream and downstream wave components. It was noted that the frequency spectra of source impedance hardly changes with the increase of engine speed. Utilizing this fact, source strength under the engine run-up condition was calculated by assuming invariant source impedance. Predicted insertion loss and radiated sound pressure level using the measured source parameters were compared with those of measured data and predicted data using several idealized source models, which have been adopted for the calculations. A reasonably good agreement was observed between measured sound spectra at the intake orifice and predicted one using the measured source data. It was shown that the source data obtained by the present method yielded a far better prediction accuracy than those by the idealized source models. 相似文献
192.
It was shown that the color property of the recognized visual space of illumination, RVSI was controlled by changing the initial visual information by arranging objects in the room all shifting toward orange direction. We constructed two miniature rooms, D and I, both illuminated by the same daylight type fluorescent lamps but arranged with furniture of different color, those in room I shifting toward color as if they were illuminated by an incandescent lamp. Subjects felt as if room I were illuminated by an incandescent lamp. A test patch was placed midair in each room and its color was judged. When the test patches were placed in room I their colors were all perceived to be shifted toward greenish blue compared to those of test patches placed in room D, in spite of having the same illumination. The results imply that the apparent color of an object is determined not by its chromaticity, but in relation to the color property of the RVSI of the room where the object is observed. 相似文献
193.
194.
Perceptual achromatic setting has been claimed to be a method of assessing the recognition of illumination in an environment.
The result, however, is not spatially valid because of some effect of an immediate area of the test (local effect). We considered
a method for excluding this local effect from the assessment. We hypothesized base on the co-planar theory and the recognized
visual space of illumination theory that a depth separation between the test and its immediate area would be an effective
way. In the first experiment, the perceptual achromatic setting was conducted in a natural scene, with several test luminance
levels. The perceptual achromatic locus from two conditions was compared. One condition is the test pasted on a chromatic
surround. The other is the test fronto-parallelly separated from the surround. In the second experiment, the perceptual achromatic
setting was conducted at the several depth separations. We found that the depth separation decreases the local effect but
it was not completely excluded. 相似文献
195.
The phase diagrams of water-cyclohexane containing 5, 10, and 20 wt% sodium 1,2-bis(2-ethylhexyloxycarbonyl)-1-ethanesulfonate (Aerosol OT, AOT) as a function of temperature were studied. There is the water phase in which AOT is dissolved and a large amount of oil is solubilized at higher temperature, and the oil phase in which AOT is dissolved and a large amount of water is solubilized at lower temperature. It is evident from the phase behavior that the hydrophile-lipophile property of AOT is well balanced. Accordingly, the phase diagram and properties of AOT solution are affected rather sensitively by the addition of a small amount of hydrophilic or lipophilic additive or by temperature. Careful elimination of inorganic salts also influences markedly the solution properties of AOT. Thus, the addition or removal of known amounts of inorganic salts, such as Na2SO4 is also very important to control the solution properties related to practical applications. In this context phase diagrams of both carefully purified and commercial AOT with or without additives have been determined. 相似文献
196.
K. Shinoda T. Hayashi T. Yoshida K. Sakai A. Nakajima 《Colloid and polymer science》1978,256(2):202-202
Ohne Zusammenfassung 相似文献
197.
K. Shinoda T. Hayashi T. Yoshida K. Sakai und A. Nakajima 《Colloid and polymer science》1978,256(2):202
Ohne Zusammenfassung 相似文献
198.
The phase diagram of the C12H25(OCH2CH2)5OH/water/tetradecane system was studied around the critical solution temperatures of surfactant-water and surfactant-oil phases. Although the phase behavior is very complicated due to the formation of liquid crystalline phase, basic phase-changes around the three-phase region, consisted of a water, a surfactant and an oil phases, are the same as those in a short-chain nonionic surfactant system. 相似文献
199.
Mari Inoki Fumihiko Akutsu Yasuyuki Kitayama Koichi Shinoda Yoshio Kasashima Kiyoshi Naruchi 《Macromolecular rapid communications》1996,17(11):805-811
Thermal reactions of alkali salts of 4-(1-bromoethyl)benzoic acid in bulk were investigated. These reactions were found to produce unexpectedly the graft copolymer, poly(4-vinylbenzoate)-graft-oligo(oxycarbonyl-1,4-phenylenethylidene) ( 1 ). The relative reactivity of the oligocondensation as well as the vinyl polymerization of the salts decreased in the following order: K > Na > Li. The reaction polymerization rate proceeded rapidly during the initial 15 min, and then slowed down. 相似文献
200.