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131.
132.
Automatic response to lane-blocking incidents is a critical issue in the field of automated highway systems (AHS). Accordingly, this paper presents a microscopic vehicular control methodology for automatic-control (AC) vehicular movements in response to lane-blocking incidents in the AHS environment. The embedded traffic control logic is based on the basic safety requirements for automatic-control lane traffic maneuvers responding to lane-blocking incidents in the single-automated-lane AHS environment. Accordingly, respective automated vehicular control models are proposed to deal with AC vehicles moving in three corresponding sequential phases, i.e., (1) AC platoon approaching the incident site from the blocked lane, (2) mandatory lane changing and mixed car following in the adjacent lane, and (3) AC platoon reforming downstream from the incident site in the blocked automated lane. Using a microscopic simulation model which embeds these proposed models, preliminary tests are conducted to investigate the relative performance of the proposed method in various traffic flow and control scenarios. The resulting numerical results, including simplified sensitivity analyses, indicate that the proposed microscopic traffic control logic permits regulating automatic-control vehicular movements in response to the effects of lane-blocking incidents on traffic flows either in control-free lanes or in the automatic-control lanes. Implications of the results and some findings are discussed for further research. 相似文献
133.
The nucleation and growth of condensate nuclei on smooth surfaces, e.g., an immiscible liquid or a smooth solid, can occur both by the direct addition of molecules from the vapor and from those adsorbed on the substrate. We show how to generalize nucleation theory to allow for the simultaneous occurrence of both mechanisms. The vapor-condensate-substrate interfacial forces, the contact angle, the critical supersaturation, and the coefficient in the adsorption isotherm are different ways of expressing the affinity between vapor molecules and the substrate surface. The critical supersaturations for nucleation on the surface of an immiscible liquid and nucleation on the surface of a perfectly smooth solid are predicted in terms of these parameters and the relationships among them. For most values of these parameters we find that adsorbed molecules are usually far more important to the nucleation process than those in the vapor phase. 相似文献
134.
Jenn-Yuan Sheu Po-Hua Chen Wei-Chang Tseng Chang-Yu Chen Li-Yu Tsai Yeou-Lih Huang 《Analytical sciences》2003,19(6):957-960
A simple and sensitive spectrophotometric method for the determination of a thiobarbituric acid-reactive substance (TBARS) in human hair has been developed. The proposed method is based on the formation of a red-colored product by the reaction of products of lipid peroxidation with thiobarbituric acid in an acidic medium. The absorbance of the resulting red product was measured at 534 nm. The linear dynamic range was between 1.0 and 20 micromol/L. The recoveries were 98.3-105.0%, and the relative standard deviations (RSD) were 0.32-1.24, respectively. TBARS in digested hair sample was stable for 3 days at room temperature. It was found that, using this method, the hair TBARS concentration in smokers (0.116 +/- 0.030 micromol/g, n = 30) was significantly higher than that in non-smokers (0.096 +/- 0.015 micromol/g, n = 30) (p < 0.05). 相似文献
135.
Quick response (QR) to passenger needs is a key objective for advanced public transportation systems (APTS), and it has become increasingly important for contemporary metropolitan bus operations to gain a competitive advantage over private transportation. This paper presents a real-time control methodology for demand-responsive bus operations that respond quickly to passenger needs. The proposed method primarily involves two levels of functionality: (1) short-term forecasting of passenger demands using time-series prediction models, and (2) identification of service strategies coupled with the associated bus service segments using fuzzy clustering technologies in response to variances in passenger demand attributes and traffic conditions. The proposed bus operations method identifies the demand-responsive vehicle service strategies primarily according to the predicted up-to-date attributes of passengers’ demands, rather than deterministic passenger arrival rates, which were generally used in previous literature. In addition, the variation of traffic conditions along bus lines is considered in the proposed method. Results from numerical studies using real data of passengers’ demands, including passenger volume at each bus stop and the passenger origin-destination (O-D) patterns, are presented to demonstrate the effectiveness of the proposed method for real-world applications. 相似文献
136.
Albert Jeu-Liang Sheu 《Communications in Mathematical Physics》1991,135(2):217-232
We show that deformation quantizations of the Poisson structures on the Poisson Lie groupSU(2) and its homogeneous space, the 2-sphere, are compatible with Woronowicz's deformation quantization ofSU(2)'s group structure and Podles' deformation quantization of 2-sphere's homogeneous structure, respectively. So in a certain sense the multiplicativity of the Lie Poisson structure onSU(2) at the classical level is preserved under quantization.With an Appendix by Jiang-Hua Lu and Alan Weinstein Department of Mathematics, University of California, Berkely, CA 94720 USAPartially supported by NSF-Grant DMS-8505550 相似文献
137.
Motivated by the work of Fleming,
we provide a general framework to associate inf-sup type values with the Isaacs equations.
We show that upper and lower bounds for the generators of inf-sup type
are upper and lower Hamiltonians, respectively.
In particular, the lower (resp. upper) bound corresponds to the
progressive (resp. strictly progressive) strategy.
By the Dynamic Programming Principle and identification of the generator,
we can prove that the inf-sup type game is characterized as the unique viscosity solution
of the Isaacs equation.
We also discuss the Isaacs equation with a Hamiltonian of a convex combination
between the lower and upper Hamiltonians. 相似文献
138.
Shieh M Ho CH Sheu WS Chen BG Chu YY Miu CY Liu HL Shen CC 《Journal of the American Chemical Society》2008,130(43):14114-14116
The unprecedented ternary Te-Fe-Cu chain polymers [{Et4N}{TeFe3(CO)9Cu}]infinity and [{TeFe3(CO)9Cu2}(mu-4,4'-dipyridyl)1.5]infinity were prepared from the self-assembly of [Et4N]2[TeFe3(CO)9] with [Cu(MeCN)4][BF4] in THF or in the presence of 4,4'-dipyridyl in THF. These two chain polymers, which can also be constructed from the precursor complex TeFe3(CO)9Cu2(MeCN)2, show semiconducting behaviors with low band gaps of 0.59 and 0.41 eV, respectively. In addition, their conductivity and the effect of the bridging ligand are further elucidated by theoretical calculations. 相似文献
139.
We suggest that the H-bond in proteins not only mirrors the motion of hydrogen in its own atomistic setting but also finds its origin in the collective environment of the hydrogen bond in a global lattice of surrounding H2O molecules. This water lattice is being perturbed in its optimal entropic configuration by the motion of the H-bond. Furthermore, bonding interaction with the lattice drop the H-bond energy from some 5 kcal/mol for the pure protein in the absence of H2O, to some 1.6 kcal/mol in the presence of the H2O medium. This low value here is determined in a computer experiment involving MD calculations and is a value close to the generally accepted value for biological systems. In accordance with these computer experiments under ambient conditions, the H-bond energy is seriously depressed, hence confirming the subtle effect of the H2O medium directly interacting with the H-bond and permitting a strong fluxional behavior. Furthermore, water produces a very large change in the entropy of activation due to the hydrogen bond breakage, which affects the rate by as much as 2 orders of magnitude. We also observe that there is an entire ensemble of H-bond structures, rather than a single transition state, all of which contribute to this H-bond. Here the model is tested by changing to D2O as the surrounding medium resulting in a substantial solvent isotope effect. This demonstrates the important influence of the environment on the individual hydrogen bond. 相似文献
140.
Chien‐Chang Shen Chwan‐Fwu Lin Yu‐Ling Huang Shr‐Ting Wan Chin‐Chu Chen Sen‐Je Sheu Yi‐Chin Lin Chien‐Chih Chen 《中国化学会会志》2008,55(4):854-857
Three new compounds, 2,4‐dimethoxy‐6‐methylbenzene‐1,3‐diol ( 1 ), salmoquinone ( 2 ), and 3‐(4‐hydroxyphenyl)‐4‐isobutyl‐1H‐pyrrole‐2,5‐dione ( 3 ), together with six known compounds, 2‐methoxy‐6‐methyl‐p‐benzoquinone ( 4 ), 2,3‐dimethoxy‐5‐methyl‐p‐benzoquinone ( 5 ), 2‐hydroxy‐5‐methoxy‐3‐methyl‐p‐benzoquinone ( 6 ), eburcoic acid ( 7 ), fomefficinic acid C ( 8 ), and a pyrroledione ( 9 ), were isolated from the mycelium of Antrodia salmonea. The structures of these compounds were elucidated by spectrometric analyses including IR, NMR, and MS. Among these compounds, 4 and 5 exhibited cytotoxicity against KB, HepG2, and H2058 cell lines. 相似文献