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1.
Diketopyrrolopyrrole‐Porphyrin Conjugates with High Two‐Photon Absorption and Singlet Oxygen Generation for Two‐Photon Photodynamic Therapy 下载免费PDF全文
Julie Schmitt Prof. Valérie Heitz Dr. Angélique Sour Dr. Frédéric Bolze Dr. Hussein Ftouni Prof. Jean‐Francois Nicoud Dr. Lucia Flamigni Dr. Barbara Ventura 《Angewandte Chemie (International ed. in English)》2015,54(1):169-173
Two‐photon photodynamic therapy is a promising therapeutic method which requires the development of sensitizers with efficient two‐photon absorption and singlet‐oxygen generation. Reported here are two new diketopyrrolopyrrole‐porphyrin conjugates as robust two‐photon absorbing dyes with high two‐photon absorption cross‐sections within the therapeutic window. Furthermore, for the first time the singlet‐oxygen generation efficiency of diketopyrrolopyrrole‐containing systems is investigated. A preliminary study on cell culture showed efficient two‐photon induced phototoxicity. 相似文献
2.
Christian Wenz Coral Barbas Ángeles López‐Gonzálvez Antonia Garcia Fernando Benavente Victoria Sanz‐Nebot Tim Blanc Gordon Freckleton Philip Britz‐McKibbin Meera Shanmuganathan Francois de l′Escaille Johann Far Rob Haselberg Sean Huang Carolin Huhn Martin Pattky David Michels Si Mou Feng Yang Christian Neusuess Nora Tromsdorf Edward E.K. Baidoo Jay D. Keasling SungAe Suhr Park 《Journal of separation science》2015,38(18):NA-NA
A collaborative study on the robustness and portability of a capillary electrophoresis‐mass spectrometry method for peptide mapping was performed by an international team, consisting of 13 independent laboratories from academia and industry. All participants used the same batch of samples, reagents and coated capillaries to run their assays, whereas they utilized the capillary electrophoresis‐mass spectrometry equipment available in their laboratories. The equipment used varied in model, type and instrument manufacturer. Furthermore, different types of sheath‐flow capillary electrophoresis–mass spectrometry interfaces were used. Migration time, peak height and peak area of ten representative target peptides of trypsin‐digested bovine serum albumin were determined by every laboratory on two consecutive days. The data were critically evaluated to identify outliers and final values for means, repeatability (precision within a laboratory) and reproducibility (precision between laboratories) were established. For relative migration time the repeatability was between 0.05 and 0.18% RSD and the reproducibility between 0.14 and 1.3% RSD. For relative peak area repeatability and reproducibility values obtained were 3–12 and 9–29% RSD, respectively. These results demonstrate that capillary electrophoresis‐mass spectrometry is robust enough to allow a method transfer across multiple laboratories and should promote a more widespread use of peptide mapping and other capillary electrophoresis‐mass spectrometry applications in biopharmaceutical analysis and related fields. 相似文献
3.
Xingjia Cheng Wen Xu Hua Wen Jing Zhang Heng Zhang Haowen Li Francois M. Peeters Qingqing Chen 《Frontiers of Physics》2023,18(5):53303
Bilayer (BL) molybdenum disulfide (MoS2) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moiré superlattices. In this work, BL MoS2 on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS2. The optical conductivity of BL MoS2 is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS2 can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS2, BL MoS2 with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS2 differ from those observed for ML MoS2. The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS2 based twistronic systems for novel applications as optical and optoelectronic materials and devices. 相似文献
4.
Computational method for phase space transport with applications to lobe dynamics and rate of escape
Lobe dynamics and escape from a potential well are general frameworks introduced to study phase space transport in chaotic dynamical systems.While the former approach studies how regions of phase space get transported by reducing the flow to a two-dimensional map, the latter approach studies the phase space structures that lead to critical events by crossing certain barriers. Lobe dynamics describes global transport in terms of lobes, parcels of phase space bounded by stable and unstable invariant manifolds associated to hyperbolic fixed points of the system. Escape from a potential well describes how the critical events occur and quantifies the rate of escape using the flux across the barriers. Both of these frameworks require computation of curves, intersection points, and the area bounded by the curves. We present a theory for classification of intersection points to compute the area bounded between the segments of the curves. This involves the partition of the intersection points into equivalence classes to apply the discrete form of Green’s theorem. We present numerical implementation of the theory, and an alternate method for curves with nontransverse intersections is also presented along with a method to insert points in the curve for densification. 相似文献
5.
Francois Golse Benoit Perthame Catherine Sulem 《Archive for Rational Mechanics and Analysis》1988,103(1):81-96
This article deals with a boundary-layer problem arising in the kinetic theory of gases when the mean free path of molecules tends to zero. The model considered here is the stationary, nonlinear Boltzmann equation in one dimension with a slightly perturbed reflection boundary condition. We restrict our attention to the case of hard spheres collisions, with Grad's cutoff assumption. Existence, uniqueness and asymptotic behavior are derived by means of energy estimates. 相似文献
6.
F. Bardot F. Villiéras L.J. Michot M. Francois G. Gérard J.M. Cases 《Journal of Dispersion Science and Technology》2013,34(6-7):739-759
ABSTRACT Ar and N2 high resolution adsorption volumetry coupled to the Derivative Isotherm Simulation method was applied on nine homoionic illite samples (Li ?, Na ? K ? Rb ? Cs ? Mg ? Ca ? Sr ? and Ba ? illites). By comparing the adsorption isotherms it appears that the nature of the surface cation strongly influences the adsorption mechanisms. The lateral and basal surface areas can only be derived from argon adsorption on monovalent samples. The argon adsorption energies varv with the nature of the surface compensating cation. Both cation size and electronegativity are involved. These interactions can, in first approach, be expressed in terms of surface tensionsγsv LW. Specific interactions appear when nitrogen is used revealing high energy adsorption sites located on basal faces. These sites could be related to some polar properties of the surface. 相似文献
7.
Franck J. Vernerey Kamtornkiat Musiket Francois Barthelat 《International Journal of Solids and Structures》2014
Natural materials and structures are increasingly becoming a source of inspiration for the design novel of engineering systems. In this context, the structure of fish skin, made of an intricate arrangement of flexible plates growing out of the dermis of a majority of fish, can be of particular interest for materials such as protective layers or flexible electronics. To better understand the mechanics of these composite shells, we introduce here a general computational framework that aims at establishing a relationship between their structure and their overall mechanical response. Taking advantage of the periodicity of the scale arrangement, it is shown that a representative periodic cell can be introduced as the basic element to carry out a homogenization procedure based on the Hill-Mendel condition. The proposed procedure is applied to the specific case of the fish skin structure of the Morone saxatilis, using a computational finite element approach. Our numerical study shows that fish skin possesses a highly anisotropic response, with a softer bending stiffness in the longitudinal direction of the fish. This softer response arises from significant scale rotations during bending, which induce a stiffening of the response under large bending curvature. Interestingly, this mechanism can be suppressed or magnified by tuning the rotational stiffness of the scale-dermis attachment but is not activated in the lateral direction. These results are not only valuable to the engineering design of flexible and protective shells, but also have implications on the mechanics of fish swimming. 相似文献
8.
Serge Raynal Gilberte Ndebeka Paul Caubere Satira Suparno Joseph Sledz Francois Schue 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):667-674
The stereoregularity of polystyrenes obtained with complex bases and salt complex bases in various solvents was determined by 13C-NMR spectroscopy. Polystyrenes produced by complex bases are mostly syndiotactic and obey Bernoullian statistics. 相似文献
9.
Ania Alik Chafiaa Bouguechtouli Manon Julien Wolfgang Bermel Rania Ghouil Sophie Zinn‐Justin Francois‐Xavier Theillet 《Angewandte Chemie (International ed. in English)》2020,59(26):10411-10415
Abundant phosphorylation events control the activity of nuclear proteins involved in gene regulation and DNA repair. These occur mostly on disordered regions of proteins, which often contain multiple phosphosites. Comprehensive and quantitative monitoring of phosphorylation reactions is theoretically achievable at a residue‐specific level using 1H‐15N NMR spectroscopy, but is often limited by low signal‐to‐noise at pH>7 and T>293 K. We have developed an improved 13Cα‐13CO correlation NMR experiment that works equally at any pH or temperature, that is, also under conditions at which kinases are active. This allows us to obtain atomic‐resolution information in physiological conditions down to 25 μm . We demonstrate the potential of this approach by monitoring phosphorylation reactions, in the presence of purified kinases or in cell extracts, on a range of previously problematic targets, namely Mdm2, BRCA2, and Oct4. 相似文献
10.
Ngoc Hoa Tran Huy Francois Mathey 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):477-481
Abstract The reaction of electron-rich alkynes such as ethoxyacetylene or propynyldiethylamine with a transient terminal phosphinidene complex such as [PhP?W(CO)5] directly yields the corresponding phosphole complexes via a formal [2 + 2 + I] cycloaddition involving two molecules of alkyne and one phosphorus center. 相似文献