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101.
Hybrid censoring scheme is a combination of Type‐I and Type‐II censoring schemes. Determination of optimum hybrid censoring scheme is an important practical issue in designing life testing experiments to enhance the information on reliability of the product. In this work, we consider determination of optimum life testing plans under hybrid censoring scheme by minimizing the total cost associated with the experiment. It is shown that the proposed cost function is scale invariant for some selected distributions. Optimum solution cannot be obtained analytically. We propose a method for obtaining the optimum solution and consider Weibull distribution for illustration. We also studied the sensitivity of the optimal solution to the misspecification of parameter values and cost components through a well‐designed sensitivity analysis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
102.
Regina Schmitt Patrick Mayer Benjamin Kirsch Jan Aurich Charlotte Kuhn Ralf Müller Kaushik Bhattacharya 《PAMM》2014,14(1):383-384
This work is motivated by cryogenic turning which allows end shape machining and simultaneously attaining a hardened surface due to deformation induced martensitic transformations. To study the process on the microscale, a multivariant phase field model for martensitic transformations in conjunction with a crystal plastic material model is introduced. The evolution of microstructure is assumed to follow a time-dependent Ginzburg-Landau equation. To solve the field equations the finite element method is used. Time integration is performed with Euler backward schemes, on the global level for the evolution equation of the phase field, and on the element level for the crystal plastic material law. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
103.
104.
Joshua P. Gray Md. Nasir Uddin Rajan Chaudhari Margie N. Sutton Hailing Yang Philip Rask Hannah Locke Brian J. Engel Nefeli Batistatou Jing Wang Brian J. Grindel Pratip Bhattacharya Seth T. Gammon Shuxing Zhang David Piwnica-Worms Joshua A. Kritzer Zhen Lu Robert C. Bast Jr. Steven W. Millward 《Chemical science》2021,12(10):3526
In recent decades it has become increasingly clear that induction of autophagy plays an important role in the development of treatment resistance and dormancy in many cancer types. Unfortunately, chloroquine (CQ) and hydroxychloroquine (HCQ), two autophagy inhibitors in clinical trials, suffer from poor pharmacokinetics and high toxicity at therapeutic dosages. This has prompted intense interest in the development of targeted autophagy inhibitors to re-sensitize disease to treatment with minimal impact on normal tissue. We utilized Scanning Unnatural Protease Resistant (SUPR) mRNA display to develop macrocyclic peptides targeting the autophagy protein LC3. The resulting peptides bound LC3A and LC3B—two essential components of the autophagosome maturation machinery—with mid-nanomolar affinities and disrupted protein–protein interactions (PPIs) between LC3 and its binding partners in vitro. The most promising LC3-binding SUPR peptide accessed the cytosol at low micromolar concentrations as measured by chloroalkane penetration assay (CAPA) and inhibited starvation-mediated GFP-LC3 puncta formation in a concentration-dependent manner. LC3-binding SUPR peptides re-sensitized platinum-resistant ovarian cancer cells to cisplatin treatment and triggered accumulation of the adapter protein p62 suggesting decreased autophagic flux through successful disruption of LC3 PPIs in cell culture. In mouse models of metastatic ovarian cancer, treatment with LC3-binding SUPR peptides and carboplatin resulted in almost complete inhibition of tumor growth after four weeks of treatment. These results indicate that SUPR peptide mRNA display can be used to develop cell-penetrating macrocyclic peptides that target and disrupt the autophagic machinery in vitro and in vivo.SUPR peptide mRNA display was used to evolve a cell-permeable, macrocyclic peptide for autophagy inhibition. 相似文献
105.
Tilak Bhattacharya 《Annali di Matematica Pura ed Applicata》1999,177(1):225-240
Summary In this work we present an elementary proof of the Faber-Krahn inequality for the first eigenvalue of the p-Laplacian on bounded
domains in ℝn. Let λ1 be the first eigenvalue and λ
1
*
be the first eigenvalue for the ball of the same volume. Then we show that λ1=λ
1
*
iff the domain is a ball. Our proof makes considerable use of the corresponding Talenti's inequality and some well known
properties of the first eigenfunction.
Entrata in Redazione il 20 aprile 1998. 相似文献
106.
Summary Cosmic-ray air shower structure functions for the distance dependence of electron density in cosmic-ray air showers in the
size range 104⋎108 have been computed for their intercomparison and comparison with Monte Carlo simulation results and measurements from recent
experiments. The analysis has yielded the present status of theoretical structure functionsvis à vis experimental results and Monte Carlo simulation distributions. The effect of core location error on the lateral distribution
of electrons is also discussed from the point of view of different theoretical and experimental results. The energy flow in
the soft component of air showers of size ∼4·105 has been evaluated within a ring of radius 10m about the axis of the showers. 相似文献
107.
Mahuya ChakrabartiA. Sarkar S. ChattapadhayayD. Sanyal A.K. PradhanR. Bhattacharya D. Banerjee 《Solid State Communications》2003,128(8):321-324
The temperature dependent (30-300 K) Doppler broadening of the positron annihilated γ-radiation measurement has been investigated on single crystalline Bi2Sr2CaCu2O8+δ (Bi-2212) high Tc superconducting samples along two different crystallographic orientations. It has been observed that throughout the temperature range the electron momentum distribution has a larger value along the crystallographic c-axis than in the a-b plane. The temperature dependent Doppler broadened positron annihilation γ-radiation lineshape analysis shows a step like increase of S-parameter at the temperature region 92-116 K. 相似文献
108.
Nibedita Bhattacharya A. Roy Chowdhury 《International Journal of Theoretical Physics》1994,33(3):679-685
We have set up the algebraic Bethe ansatz equation for an open Heisenberg spin chain having an impurity of a different type of spin. The chain is considered to be open and hence the QISM approach as modified by Sklyanin is used to set up the equations for the Bethe ansatz. 相似文献
109.
Using the pseudopotential method, theoretical investigation has been made on the firstorder Korteweg-deVries ion-acoustic
solitons in a multicomponent plasma consisting of warm positive ions, negative ions and isothermal electrons. The effects
of electron-inertia and drift motion of the ions on the amplitudes and widths of the solitons have been studied in a plasma
having (H+, Cl−), (H+, O−), (He+, H−) and (He+, O−) ions. Ion-acoustic double-layers have also been investigated for such plasmas. It has been found that drift velocity and
electron-inertia have significant contribution on the formation of double-layers in multicomponent plasma 相似文献
110.
R. C. Barnà D. De Pasquale A. Italiano A. Trifirò M. Trimarchi C. Beck C. Bhattacharya F. Haas V. Rauch M. Rousseau O. Stezowsky A. Strazzeri 《Acta Physica Hungarica A》2002,16(1-4):281-289
The 132 MeV 16O + 58Ni reaction has been experimentally investigated by using coincident charged particle techniques. A closed-form theoretical approach, describing in a simple picture the non-equilibrium component and the evaporative one of the angular correlation between light particles and reaction residues emitted in a peripheral heavy-ion collision, is applied — in the hypotesis of a sequential process — to the (C,N,O)-α and (C,N,O)-p differential multiplicities for the 16O + 58Ni at 8.25 MeV/A deep inelastic collision. From this analysis some reaction mechanism information is deduced. 相似文献