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Kevin Kam Fung Yuen 《Fuzzy Optimization and Decision Making》2014,13(1):105-130
Group decision making is the process to explore the best choice among the screened alternatives under predefined criteria with corresponding weights from assessment of a group of decision makers. The Fuzzy TOPSIS taking an evaluated fuzzy decision matrix as input is a popular tool to analyze the ideal alternative. This research, however, finds that the classical fuzzy TOPSIS produces a misleading result due to some inappropriate definitions, and proposes the rectified fuzzy TOPSIS addressing two technical problems. As the decision accuracy also depends on the evaluation quality of the fuzzy decision matrix comprising rating scores and weights, this research applies compound linguistic ordinal scale as the fuzzy rating scale for expert judgments, and cognitive pairwise comparison for determining the fuzzy weights. The numerical case of a robot selection problem demonstrates the hybrid approach leading to the much reliable result for decision making, comparing with the conventional fuzzy Analytic Hierarchy Process and TOPSIS. 相似文献
64.
(WO3)0.15(BiO1.5)0.85 exhibits a tetragonal structure derived from the fluorite subcell. The electrical conductivity of (WO3)0.15(BiO1.5)0.85 is lower than that of Y2O3-doped Bi2O3. The structure and electrical conductivity of samples formulated as (YO1.5)
x
(WO3)0.15(BiO1.5)0.85-
x
(x = 0.1, 0.2, 0.3, and 0.4) were investigated. The as-sintered (YO1.5)0.1(WO3)0.15(BiO1.5)0.75 exhibited a single cubic structure that is isostructural with δ-Bi2O3. For x = 0.2, 0.3, and 0.4, the as-sintered samples consisted of a cubic fluorite structure and rhombohedral Y6WO12. After heat treatment at 600 °C for 200 h, the cubic structures are stable for x = 0.1, 0.3, and 0.4. A transformation from cubic to rhombohedral phase after heat treatment at 600 °C for 200 h was observed
in the sample originally formulated as (YO1.5)0.2(WO3)0.15(BiO1.5)0.65. 相似文献
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Synthesis and thermal properties of mesomorphic 1,1'-bis[ω-(4'-cyano-4-biphenyloxy)alkyl] ferrocenes
A new series of 1,1'-disubstituted ferrocene compounds of the type [(η5-C5H4(CH2)nOC6H4C6H4CN]2Fe (3a-d, n = 5, 6, 8, 11) incorporating a variable length alkyloxy cyanobiphenyl unit has been prepared and their mesomorphic properties have been investigated. Compounds 3b, c and d exhibit a thermotropic smectic C phase and 3c also exhibits a monotropic smectic A phase over a fairly wide range near ambient temperature. 相似文献
67.
Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Naik P Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Galik RS Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H Mohapatra D Onyisi PU Patterson JR Peterson D Pivarski J 《Physical review letters》2007,99(19):191801
Using a 281 pb{-1} data sample collected at the psi(3770) with the CLEO-c detector, we present the first absolute branching fraction measurement of the decay D0-->K(-)pi(+)pi(-)e(+)nu(e) at a statistical significance of about 4.0 standard deviations. We find 10 candidates consistent with the decay D0-->K(-)pi(+)pi(-)e(+)nu(e). The probability that a background fluctuation accounts for this signal is less than 4.1 x 10{-5}. We find B(D0-->K(-)pi(+)pi(-)e(+)nu(e)) = [2.8{-1.1}{+1.4}(stat)+/-0.3(syst)]x10{-4}. By restricting the invariant mass of the hadronic system to be consistent with K1(1270), we obtain the product of branching fractions B(D{0}-->K{1}{-}(1270)e{+}nu{e})xB(K1-(1270)-->K{-}pi{+}pi{-})=[2.5{-1.0}{+1.3}(stat)+/-0.2(syst)]x10{-4}. Using B(K1-(1270)-->K{-}pi{+}pi{-})=(33+/-3)%, we obtain B(D{0}-->K{1}{-}(1270)e{+}nu{e})=[7.6{-3.0}{+4.1}(stat)+/-0.6(syst)+/-0.7]x10{-4}. The last error accounts for the uncertainties in the measured K1-(1270)-->K{-}pi{+}pi{-} branching fractions. 相似文献
68.
A new technique has been developed to compute mean and fluctuating concentrations in complex turbulent flows. An initial distribution of material is discretised into any small clouds which are advected by a combination of the mean flow and large scale turbulence. The turbulence can be simulated either by Kinematic Simulation or by a stochastic model for the motion of each cloud centroid. The clouds also diffuse relative to their centroids; the statistics for this are obtained from a separate calculation of the growth of individual clouds in small scale turbulence, generated by Kinematic Simulation. The ensemble of discrete clouds is periodically rediscretised, to limit the size of the small clouds and prevent overlapping. The model is illustrated with simulations of dispersion in uniform flow and in a coastal flow, and the results are compared with analytic, steady state solutions where available. 相似文献
69.
Sia Nemat-Nasser 《Meccanica》1990,25(4):223-229
Summary I consider the kinematical implications embedded in the decomposition of the deformation gradient F into two constituents, F* (say, elastic) and Fp (say, plastic), in the form F=F* Fp. Whatever the origin, nature, and physical meaning of these three deformation gradients, the decomposition can always be recast in the form F==V* Q Up, where V* and Up are stretch tensors, respectively associated with F* and Fp, and Q is a unique rotation tensor. It then follows that the (elastic) spin associated with V* and the (plastic) spin associated with Up are fully defined by their corresponding deformation rates. I give explicit expressions defining elastic and plastic spins in terms of the elastic and plastic deformation rates, respectively. I show that, if the total velocity gradient and either the elastic or the plastic (but not both) deformation rate tensor, are given, then all the remaining kinematical rate quantities can be calculated explicitly, with no constitutive or other assumptions. I give explicit expressions for the rate of change of V*, Q, and Up, from which these quantities can be incrementally but directly obtained. In particular, I give explicit expressions for the elastic spin, plastic spin, and the rigid spin. Constitutive implications of these purely kinematical results are briefly discussed in connection with rate-independent and rate-dependent phenomenological elastoplasticity, and, particularly, kinematical hardening.
Invited Lecture presented at New Developments in Structural Mechanichs, International Meeting in memory of Professor Manfredi Romano; Catania, Italy, 4–6 July 1990. 相似文献
Sommario Si considerano le implicazioni cinematiche insite nella decomposizione del gradiente di deformazione F in due componenti, F* (per esempio, la parte elastica) ed Pp (per esempio, la parte plastica), nella forma F=F*Fp. Qualunque sia l'origine, la natura e il significato fisico di questi tre gradienti, la decomposizione si può sempre riscrivere nella forma F=U* Q Up, in cui V* ed Up sono tensori di deformazione associati rispettivamente con F* ed Fp, e Q è un tensore di rotazione univocamente definito. Ne segue che lo spin (elastico) associato con U* e lo spin (plastico) associato con Up sono completamente definiti dalle corrispondenti derivate delle deformazioni: di questa dipendenza si forniscono le espressioni esplicite. Si mostra quindi che, se sono dati il gradiente della velocità totale e il tensore delle deformazioni elastiche o quello delle deformazioni plastiche (ma non entrambi), tutte le altre quantità cinematiche possono essere calcolate esplicitamente, senza alcuna ulteriore ipotesi, neanche sulla legge costitutiva. Si forniscono ancora espressioni per i gradienti di V*, Q ed Up, dalle quali queste quantità si possono ottenere direttamente, per incrementi successivi: in particolare, si danno espressioni esplicite per lo spin elastico, plastico e rigido. Si discutono brevemente le implicazioni costitutive di questi risultati puramente cinematici, in connessione con vari aspetti fenomenologici dell'elasto-plasticità, e in particolare l'incrudimento cinematico.
Invited Lecture presented at New Developments in Structural Mechanichs, International Meeting in memory of Professor Manfredi Romano; Catania, Italy, 4–6 July 1990. 相似文献
70.
Dong M Si YQ Sun SY Pu XP Yang ZJ Zhang LR Zhang LH Leung FP Lam CM Kwong AK Yue J Zhou Y Kriksunov IA Hao Q Lee HC 《Organic & biomolecular chemistry》2011,9(9):3246-3257
Human CD38 is a novel multi-functional protein that acts not only as an antigen for B-lymphocyte activation, but also as an enzyme catalyzing the synthesis of a Ca(2+) messenger molecule, cyclic ADP-ribose, from NAD(+). It is well established that this novel Ca(2+) signaling enzyme is responsible for regulating a wide range of physiological functions. Based on the crystal structure of the CD38/NAD(+) complex, we synthesized a series of simplified N-substituted nicotinamide derivatives (Compound 1-14). A number of these compounds exhibited moderate inhibition of the NAD(+) utilizing activity of CD38, with Compound 4 showing the highest potency. The crystal structure of CD38/Compound 4 complex and computer simulation of Compound 7 docking to CD38 show a significant role of the nicotinamide moiety and the distal aromatic group of the compounds for substrate recognition by the active site of CD38. Biologically, we showed that both Compounds 4 and 7 effectively relaxed the agonist-induced contraction of muscle preparations from rats and guinea pigs. This study is a rational design of inhibitors for CD38 that exhibit important physiological effects, and can serve as a model for future drug development. 相似文献