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排序方式: 共有640条查询结果,搜索用时 390 毫秒
631.
Heather D. Agnew Rosemary D. Rohde Steven W. Millward Dr. Arundhati Nag Woon‐Seok Yeo Dr. Jason E. Hein Dr. Suresh M. Pitram Dr. Abdul Ahad Tariq Vanessa M. Burns Russell J. Krom Valery V. Fokin Prof. K. Barry Sharpless Prof. James R. Heath Prof. 《Angewandte Chemie (International ed. in English)》2009,48(27):4944-4948
Special agents for protein capture : Iterative in situ click chemistry (see scheme for the tertiary ligand screen) and the one‐bead–one‐compound method for the creation of a peptide library enable the fragment‐based assembly of selective high‐affinity protein‐capture agents. The resulting ligands are water‐soluble and stable chemically, biochemically, and thermally. They can be produced in gram quantities through copper(I)‐catalyzed cycloaddition.
632.
A simple, but still three-dimensional, model describing the morphological stability of realistic SiGe islands on Si(001) is presented. The experimental evolution toward steeper islands with volume can be predicted for any average composition. Despite the use of elastic theory for stress relaxation under the assumption of a uniform SiGe distribution, and of a common mean surface energy of the faceted islands, the model seems to capture the essence of the energetic balance determining the morphological evolution with volume, with no fitting parameters. This is suggested by close comparison with molecular beam epitaxy data at three different temperatures (i.e.?compositions). The good agreement also allows for interpreting the minor scattering of experimental data with temperature and provides a reliable tool for extracting the average Ge content from standard atomic force microscopy analysis. 相似文献
633.
Peter Zalden Giuliana Aquilanti Carmello Prestipino Olivier Mathon Bérangère André Matthias Wuttig Marie‐Vanessa Coulet 《Journal of synchrotron radiation》2012,19(5):806-813
A Calvet‐type differential scanning calorimeter has been implemented on a synchrotron beamline devoted to X‐ray absorption spectroscopy. As a case study, the complex crystallization process in amorphous Ge15Sb85 phase‐change material is followed by simultaneous calorimetric and quick‐EXAFS measurements. A first crystallization at 514(1) K is related to the crystallization of an Sb‐rich phase accompanied by segregation of Ge atoms. Upon further heating, the as‐formed amorphous Ge regions crystallize at 604(1) K. A quantitative analysis of the latent heat allows a Ge11Sb89 stoichiometry to be proposed for the first crystallized phase. 相似文献
634.
635.
Vanessa Izquierdo-Snchez Pablo C. Zambrano-Rodríguez Nadia Pea-Merino Sirio Bolaos-Puchet Horacio J. Reyes-Alva Angelina Martínez-Cruz Sa Muiz-Hernndez Gabriel Guízar-Sahagún Luis Alberto Medina 《Molecules (Basel, Switzerland)》2021,26(23)
Spinal cord injury (SCI) refers to the damage suffered in the spinal cord by any trauma or pathology. The purpose of this work was to determine whether 99mTc-GA-5, a radiotracer targeting Glial Fibrillary Acidic Protein (GFAP), can reveal in vivo the reactivation of astrocytes in a murine model with SCI. A method for the 99mTc radiolabeling of the mouse anti-GFAP monoclonal antibody GA-5 was implemented. Radiochemical characterization was performed, and radioimmunohistochemistry assays were used to evaluate the integrity of 99mTc-GA-5. MicroSPECT/CT was used for in vivo imaging to trace SCI in the rats. No alterations in the GA-5’s recognition/specificity ability were observed after the radiolabeling. The GA-5’s radiolabeling procedure implemented in this work offers a practical method to allow the in vivo following of this monoclonal antibody to evaluate its biodistribution and specificity for GFAP receptors using SPECT/CT molecular imaging. 相似文献
636.
Abdalghani Daaoub James M. F. Morris Vanessa A. Béland Paul Demay-Drouhard Amaar Hussein Simon J. Higgins Hatef Sadeghi Richard J. Nichols Andrea Vezzoli Thomas Baumgartner Sara Sangtarash 《Angewandte Chemie (International ed. in English)》2023,62(24):e202302150
Most studies in molecular electronics focus on altering the molecular wire backbone to tune the electrical properties of the whole junction. However, it is often overlooked that the chemical structure of the groups anchoring the molecule to the metallic electrodes influences the electronic structure of the whole system and, therefore, its conductance. We synthesised electron-accepting dithienophosphole oxide derivatives and fabricated their single-molecule junctions. We found that the anchor group has a dramatic effect on charge-transport efficiency: in our case, electron-deficient 4-pyridyl contacts suppress conductance, while electron-rich 4-thioanisole termini promote efficient transport. Our calculations show that this is due to minute changes in charge distribution, probed at the electrode interface. Our findings provide a framework for efficient molecular junction design, especially valuable for compounds with strong electron withdrawing/donating backbones. 相似文献
637.
Dr. Xiuxiu Yang Jennifer Kuziola Dr. Vanessa A. Béland Julia Busch Dr. Markus Leutzsch Dr. Jordi Burés Dr. Josep Cornella 《Angewandte Chemie (International ed. in English)》2023,62(32):e202306447
In this article we report that a cationic version of Akiba's BiIII complex catalyzes the reduction of amides to amines using silane as hydride donor. The catalytic system features low catalyst loadings and mild conditions, en route to secondary and tertiary aryl- and alkylamines. The system tolerates functional groups such as alkene, ester, nitrile, furan and thiophene. Kinetic studies on the reaction mechanism result in the identification of a reaction network with an important product inhibition that is in agreement with the experimental reaction profiles. 相似文献
638.
Vanessa Styles James Van Yperen 《Numerical Methods for Partial Differential Equations》2023,39(1):133-162
We consider a semidiscrete finite element approximation for a system consisting of the evolution of a planar curve evolving by forced curve shortening flow inside a given bounded domain , such that the curve meets the boundary orthogonally, and the forcing is a function of the solution of a reaction–diffusion equation that holds on the evolving curve. We prove optimal order error bounds for the resulting approximation and present numerical experiments. 相似文献
639.
Michel Duprez Vanessa Lleras Alexei Lozinski 《Numerical Methods for Partial Differential Equations》2023,39(1):281-303
We present a new finite element method, called -FEM, to solve numerically elliptic partial differential equations with natural (Neumann or Robin) boundary conditions using simple computational grids, not fitted to the boundary of the physical domain. The boundary data are taken into account using a level-set function, which is a popular tool to deal with complicated or evolving domains. Our approach belongs to the family of fictitious domain methods (or immersed boundary methods) and is close to recent methods of CutFEM/XFEM type. Contrary to the latter, -FEM does not need any nonstandard numerical integration on cut mesh elements or on the actual boundary, while assuring the optimal convergence orders with finite elements of any degree and providing reasonably well conditioned discrete problems. In the first version of -FEM, only essential (Dirichlet) boundary conditions was considered. Here, to deal with natural boundary conditions, we introduce the gradient of the primary solution as an auxiliary variable. This is done only on the mesh cells cut by the boundary, so that the size of the numerical system is only slightly increased. We prove theoretically the optimal convergence of our scheme and a bound on the discrete problem conditioning, independent of the mesh cuts. The numerical experiments confirm these results. 相似文献
640.