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61.
62.
Kim KC Hauke F Hirsch A Boyd PD Carter E Armstrong RS Lay PA Reed CA 《Journal of the American Chemical Society》2003,125(14):4024-4025
A heterofullerene isoelectronic to C60 is reported. The azafullerenium cation C59N+ can be isolated in good yield as a carborane salt via the two-electron oxidation of the C-C bond of (C59N)2 dimer. [C59N][Ag(CB11H6Cl6)2] has been characterized by electronic, IR, Raman, and 13C NMR spectroscopies, MALDI spectrometry, DFT calculations, and X-ray crystallography. 相似文献
63.
Hauke Reddmann Christos Apostolidis Olaf Walter Jean Rebizant Hanns‐Dieter Amberger 《无机化学与普通化学杂志》2005,631(8):1487-1496
Electronic Structures of Highly Symmetrical Compounds of f Elements. 38 [1] Crystal, Molecular and Electronic Structure of Tris(hydrotris(1‐pyrazolyl)borato)samarium(III) Tris(hydrotris(1‐pyrazolyl)borato)samarium(III) (SmTp3) crystallizes in the space group P63/m (No. 176) with two molecules in the unit cell. The Sm3+ central ion is coordinated by nine N atoms in the shape of a tricapped trigonal prism, leading to an effective crystal field (CF) of D3h symmetry. The underlying CF splitting pattern was extracted from the absorption and luminescence spectra run at room and low temperatures, and simulated by fitting the free parameters of a phenomenological Hamiltonian achieving an r.m.s. deviation of 9.4 cm?1 for 58 assignments. The parameters used allow the estimation of the global ligand field strength experienced by the Sm3+ central ion, the insertion of SmTp3 into empirical nephelauxetic and relativistic nephelauxetic series, and the set‐up of experimentally based nonrelativistic and relativistic molecular orbital schemes in the f range. 相似文献
64.
Hanns-Dieter Amberger Stefan Jank Hauke Reddmann Norman M Edelstein 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(2):379-396
The absorption und magnetic circular dichroism spectra of the dissolved trigonal-bipyramidal complex Pr[N(SiMe3)2]3(CNtBu)2 (1) as well as the luminescence and absorption spectra of both solid 1 and solid Pr[N(SiMe3)2]3(CNC6H11)2 (2) (pellets, unoriented single crystals) were measured at ambient and low temperatures. Because of the violation of the selection rules for D3h symmetry by both compounds a reliable crystal field(CF) splitting pattern for the ground manifold 3H4, but only a plausible for the f 2 configuration could be derived on the basis of these measurements. The latter could be simulated with a reduced r.m.s. deviation of 32.6 cm(-1) for 29 assignments by fitting the free parameters of a phenomenological Hamiltonian. The adequacy of the calculated wavefunctions of this fit in the low energy range is proved by the excellent agreement of calculated and experimental temperature dependence of mu2(eff) for compound 1. The CF parameters of this fit are considered as a "master set" of CF parameters for future CF analyses of the electronic structures of trigonal bipyramidally coordinated lanthanide(III) systems. 相似文献
65.
Recently, we developed an explicit a posteriori error estimator especially suited for fluid dynamics problems solved with a stabilized method. The technology is based upon the theory that inspired stabilized methods, namely, the variational multiscale theory. The salient features of the formulation are that it can be readily implemented in existing codes, it is a very economical procedure, and it yields very accurate local error estimates uniformly from the diffusive to the advective regime. In this work, the variational multiscale error estimator is applied to develop adaptive strategies for the advection–diffusion‐reaction equation. The performance of L1 and L2 local error norms combined with three strategies to adapt the mesh is investigated. Emphasis is placed on flows with sharp boundary and interior layers but also attention is given to diffusion‐dominated flows. Computational results show that the method generates meshes with a smooth transition of the element size, which capture all the flow features. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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67.
Stefan Wild Michael Fickert Aleksandra Mitrovic Vicent Lloret Christian Neiss Jos Alejandro Vidal‐Moya Miguel ngel Rivero‐Crespo Antonio Leyva‐Prez Katharina Werbach Herwig Peterlik Mathias Grabau Haiko Wittkmper Christian Papp Hans‐Peter Steinrück Thomas Pichler Andreas Grling Frank Hauke Gonzalo Abelln Andreas Hirsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5820-5826
68.
Tao Wei Malte Kohring Muqing Chen Shangfeng Yang Heiko B. Weber Frank Hauke Andreas Hirsch 《Angewandte Chemie (International ed. in English)》2020,59(14):5602-5606
Patterned graphene‐functionalization with a tunable degree of functionalization can tailor the properties of graphene. Here, we present a new reductive functionalization approach combined with lithography rendering patterned graphene‐functionalization easily accessible. Two types of covalent patterning of graphene were prepared and their structures were unambiguously characterized by statistical Raman spectroscopy together with scanning electron microscopy/energy‐dispersive X‐ray spectroscopy (SEM‐EDS). The reversible defunctionalization processes, as revealed by temperature‐dependent Raman spectroscopy, enable the possibility to accurately modulate the degree of functionalization by annealing. This allows for the management of chemical information through complete write/store/erase cycles. Based on our strategy, controllable and efficient patterning graphene‐functionalization is no longer a challenge and facilitates the development of graphene‐based devices. 相似文献
69.
Frida Mariana Morais Friederike Buchholz Tom Hartmann Johannes Lerchner Thomas R. Neu Bärbel Kiesel Hauke Harms Thomas Maskow 《Journal of Thermal Analysis and Calorimetry》2014,115(3):2203-2210
Bacteriophages or phage-derived biological structures are a promising alternative to the application of antibiotics to eradicate biofilms. These countermeasures are highly cell specific. For a better understanding of the sequence of the underlying processes (attachment, infection, multiplication, phage release), for optimization of phage applications, or simply for screening of suitable phages or phage-derived enzymes, real-time monitoring devices are urgently required. Calorimetry is promising because it is non-invasive and quantitatively connected to the metabolic fluxes. Chip-calorimetry provides real-time information about biofilm eradication by phages. This was confirmed by comparison with reference analyses (i.e., confocal laser scanning microscopy, colony plate counts, or phage titre determination). Furthermore, chip-calorimetry provides additional information which was not captured by the reference methods such as the enhanced cell-specific heat production caused by the infection process and a residual activity of seemingly persistent bacteria. 相似文献
70.
A Supramolecular Approach for the Facile Solubilization and Separation of Covalently Functionalized Single‐Walled Carbon Nanotubes 下载免费PDF全文
Sebastian Bosch Lukas Zeininger Dr. Frank Hauke Prof. Dr. Andreas Hirsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(9):2537-2541
Through a combination of an electronic‐type selective diazonium‐based attachment of a Hamilton receptor unit onto the carbon nanotube framework and a supramolecular recognition approach of a cyanuric acid derivative, we herein introduce a highly promising strategy for the tuning of carbon nanotube solubility and, directly related to that, a solution‐based easy and straightforward separation of covalently functionalized carbon nanotube derivatives with respect to their unfunctionalized counterparts. The supramolecular complexation of the cyanuric acid derivative provides the driving force for the dramatically increased dispersibility and for the long‐time stability of the individualized single‐walled carbon nanotube derivatives in chloroform. The selective covalent functionalization of metallic carbon nanotubes can easily be analyzed with the aid of scanning Raman microscopy techniques. The functional derivatives have furthermore been characterized by UV/Vis‐NIR and fluorescence spectroscopy as well as by mass spectrometric coupled thermogravimetric analysis. The investigation of the supramolecular complexation is based on an in‐depth UV/Vis‐NIR analysis and atomic force microscopy investigations. 相似文献