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151.
Cedric Dielemann Dominique Matt Peter G. Jones Holger Thnnessen 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):o247-o249
The title compound, 25,26:27,28‐bis(methylenedioxy)pentacyclo[19.3.1.13,7.19,13.115,19]octacosa‐1(25)3,5,7(28),9,11,13(27),15,17,19(26),21,23‐dodecaene dichloromethane solvate, C30H24O4·CH2Cl2, possesses crystallographic twofold symmetry in both components. The calixarene shows a pinched cone conformation with an elliptical cavity, in which the guest dichloromethane solvent molecule is accommodated. The contact distance between guest and host (H⋯ring centroid = 2.44 Å) is extremely short. 相似文献
152.
Feyisara Eyiwumi Oni Qassim Esmaeel Joseph Tobias Onyeka Rasheed Adeleke Cedric Jacquard Christophe Clement Harald Gross Essaid Ait Barka Monica Hfte 《Molecules (Basel, Switzerland)》2022,27(2)
Pseudomonas lipopeptides (Ps-LPs) play crucial roles in bacterial physiology, host–microbe interactions and plant disease control. Beneficial LP producers have mainly been isolated from the rhizosphere, phyllosphere and from bulk soils. Despite their wide geographic distribution and host range, emerging evidence suggests that LP-producing pseudomonads and their corresponding molecules display tight specificity and follow a phylogenetic distribution. About a decade ago, biocontrol LPs were mainly reported from the P. fluorescens group, but this has drastically advanced due to increased LP diversity research. On the one hand, the presence of a close-knit relationship between Pseudomonas taxonomy and the molecule produced may provide a startup toolbox for the delineation of unknown LPs into existing (or novel) LP groups. Furthermore, a taxonomy–molecule match may facilitate decisions regarding antimicrobial activity profiling and subsequent agricultural relevance of such LPs. In this review, we highlight and discuss the production of beneficial Ps-LPs by strains situated within unique taxonomic groups and the lineage-specificity and coevolution of this relationship. We also chronicle the antimicrobial activity demonstrated by these biomolecules in limited plant systems compared with multiple in vitro assays. Our review further stresses the need to systematically elucidate the roles of diverse Ps-LP groups in direct plant–pathogen interactions and in the enhancement of plant innate immunity. 相似文献
153.
Using an image rectification application arising in the field of forest management, we demonstrate in this paper the practical
feasibility of applying thin plate spline (TPS) techniques to real image warping problems. The use of TPS‐based warping in
large problems can be limited by two factors: numerical instability in the calculation of TPS coefficients, and the intensive
computation involved in evaluating TPS functions. Both drawbacks can be overcome by taking advantage of some recent advances
in the numerical analysis of radial basis functions. Here we relate our experience in applying some of this work to realize
successful TPS warping of large forestry images, and some graphical examples are given. Methods for automated control point
selection and editing are also presented, and a cross‐correlation technique for evaluating the effectiveness of the warps
is described. This experience has guided our development of an effective and efficient software package for control point
selection and TPS warping of digital images.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
154.
Sebastian V. Kruppa Cedric Groß Xin Gui Florian Bäppler Björn Kwasigroch Dr. Yu Sun Prof. Dr. Rolf Diller Prof. Dr. Wim Klopper Prof. Dr. Gereon Niedner-Schatteburg Dr. Christoph Riehn Prof. Dr. Werner R. Thiel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11269-11284
The photoexcitation of a triangular silver(I) hydride complex, [Ag3(μ3-H)(μ2-dcpm)3](PF6)2 ([ P ](PF6)2, dcpm=bis(dicyclohexylphosphino)methane), designed with “UV-silent” bis-phosphine ligands, provokes hydride-to-Ag3 single and double electron transfer. The nature of the electronic transitions has been authenticated by absorption and photodissociation spectroscopy in parallel with high-level quantum-chemical computations utilizing the GW method and Bethe–Salpeter equation (GW-BSE). Specific photofragments of mass-selected [ P ]2+ ions testify to charge transfer and competing pathways resulting from the unique [Ag3(μ3-H)]2+ scaffold. This structural motif of [ P ](PF6)2 has been unequivocally verified by 1H NMR spectroscopy in concert with DFT and X-ray diffraction structural analysis, which revealed short equilateral Ag–Ag distances (dAgAg=3.08 Å) within the range of argentophilic interactions. The reduced radical cation [ P ] . + exhibits strong oxophilicity, forming [ P +O2] .+ ,which is a model intermediate for silver oxidation catalysis. 相似文献
155.
156.
P. Lahorte W. Mondelaers D. De Frenne F. Callens G. Vanhaelewyn E. Schacht S. Van Calenberg O. Van Cleemput A. Huyghebaert 《Radiation Physics and Chemistry》1999,55(5-6):761-765
The Department of Subatomic and Radiation Physics of the University Gent is equipped with a 15 MeV 20 kW linear electron accelerator (linac) facility. In its present configuration the accelerator is used as a multipurpose apparatus for research in the fields of polymer chemistry, biomedical materials, medicine, food technology, dosimetry, solid state physics, agriculture and nuclear and radiation physics. We present an overview of both the various research projects around our linac facility involving radiation chemistry and physics and the specialised technologies facilitating this research. 相似文献
157.
In processes such as Fluid Coking?,agglomerate formation should be minimized since it reduces the yield of valuable products,and degrades operability because of the fouling of internals.An experimental model,consisting of an aqueous solution of gum arabic with a dye,has been successfully developed to simulate the formation of agglomerates in the Fluid Coking?process,where bitumen is sprayed into a fluidized bed of coke particles The particles wetted by a spray could be predicted by assuming that all the particles in the wake of bubbles formed from the tip of the spray jet have been wetted by the injected liquid.The transfer of liquid from particles wetted with the spray to dry bed particles was relatively ineffective,as the number of wet particles increased by only 50%.With successive liquid injections,the proportion of the liquid trapped in agglomerates increases in latter injections:large agglomerates from earlier injections accumulate above the grid and are carried by gas bubbles into the spray jet cavity,where they seed fresh agglomerates. 相似文献
158.
Research in the late 1940s in academic institutions, most notably the University of Hull in the UK, led to the development of liquid crystal display technology in the 1970s, which has subsequently had a large impact throughout the world. The liquid crystal technology is based on simple organic molecules. Since the late 1980s, some liquid crystal scientists have turned their attention to investigating the effect of introducing a metal atom into the systems. This review focuses on the major developments in the field of ferrocenyl‐containing liquid crystals in which the organometallic group is situated in a terminal position with respect to the core of the molecule. Metallomesogens with terminal metal atoms are not very common, since it can be deduced from the theory of organic liquid crystals that bulky terminal groups would not be conducive to the stabilization of liquid crystal phases. Nevertheless, a terminal ferrocenyl group can stabilize a nematic liquid crystal phase and examples of this will be discussed in this review. Copyright © 2001 John Wiley & Sons Ltd. 相似文献
159.
Ignatii Zaitsev Agnieszka Anna Corley-Wiciak Cedric Corley-Wiciak Marvin Hartwig Zoellner Carsten Richter Edoardo Zatterin Michele Virgilio Beatriz Martín-García Davide Spirito Costanza Lucia Manganelli 《固体物理学:研究快报》2024,18(3):2300348
Germanium–tin (GeSn) microdisks are promising structures for complementary metal–oxide–semiconductor-compatible lasing. Their emission properties depend on Sn concentration, strain, and operating temperature. Critically, the band structure of the alloy varies along the disk due to different lattice deformations associated with mechanical constraints. An experimental and numerical study of Ge1−x Sn x microdisk with Sn concentration between 8.5 and 14 at% is reported. Combining finite element method calculations, micro-Raman and X-ray diffraction spectroscopy enables a comprehensive understanding of mechanical deformation, where computational predictions are experimentally validated, leading to a robust model and insight into the strain landscape. Through micro-photoluminescence experiments, the temperature dependence of the bandgap of Ge1−x Sn x is parametrized using the Varshni formula with respect to strain and Sn content. These results are the input for spatially dependent band structure calculations based on deformation potential theory. It is observed that Sn content and temperature have comparable effects on the bandgap, yielding a decrease of more than 20 meV for an increase of 1 at% or 100 K, respectively. The impact of the strain gradient is also analyzed. These findings correlate structural properties to emission wavelength and spectral width of microdisk lasers, thus demonstrating the importance of material-related consideration on the design of optoelectronic microstructures. 相似文献