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991.
Andreas Tengå Sven Lidin Prof. Jean‐Philippe Belieres Prof. Nathan Newman Prof. Yang Wu Ulrich Häussermann Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(27):6704-6710
Although free from structural disorder , the new intermetallic compound Cd13?xInySb10 (see figure) displays similarly low thermal conductivity values as disordered thermoelectric β‐Zn4Sb3 with an isostructural framework.
992.
To address people's concerns of exogenous oxytocin (OT) administration to lactating bovines, a study was undertaken to (a) establish an enzyme immunoassay (EIA) for OT determination in milk, (b) quantify OT in milk of cows administered OT, and (c) study influence of pasteurization on OT stability in milk. A sensitive EIA validated according to the criteria of European Union—Decision 2002/657/EC was developed for OT in skim milk in an analytical range of 10-250 pg mL−1 with a decision limit (CCα) of 30 pg mL−1 and detection capability (CCβ) of 41.5 pg mL−1. Milk samples collected from cows (n = 38) administered either 25 or 50 IU OT prior to milking were investigated for the presence of OT. There was no significant difference among both groups with the mean concentrations of OT being 15.8 and 14.9 pg mL−1 for cows subjected to 25 and 50 IU OT administration, respectively. The OT levels in skim milk of control cows (n = 30; untreated) were basal (around 10 pg mL−1). All the analyzed milk samples were below the CCα value of 30 pg mL−1. Pasteurization of OT spiked milk samples at different temperature and sample holding conditions reduced the immunological activity of OT to 43% at 110 °C. However, no further decline occurred in the immunological activity with increased pasteurization temperature and time. It was concluded that the milk OT concentrations after OT administrations were minimal and below the assay decision limit. However, OT was quite stable to pasteurization in OT spiked milk. 相似文献
993.
Samples of the solid solution [ZnSnSb2]1−x[2(InSb)]x have been prepared over the whole range of composition by tin flux synthesis. The lattice parameter of the sphalerite-type average structure varies linearly between that of the end members ZnSnSb2 and InSb, a=6.2849(2) and 6.4776(15), respectively. Electron diffraction shows different kinds of structured diffuse scattering for Zn and In rich samples, respectively. The former is attributed to compositional short range ordering, the latter to thermally excited phonon modes. A metal-nonmetal transition takes place between the compositions x=0.8 and x=0.9. 相似文献
994.
A novel free-flow electrophoresis glass chip design with two-depth etched structures for the separation and fractionation of proteins is presented. The microfluidic structures etched in two depths enhance the flow characteristics inside the miniaturized device. A novel nine-port outlet interface enables the fractionation of the separated analytes. The separation and focussing of a protein sample mixture demonstrated the ability of the new chip. 相似文献
995.
Miroslava Malenovska Marco Litschauer Marie-Alexandra Neouze Ulrich Schubert Anna Peled Jean-Paul Lellouche 《Journal of organometallic chemistry》2009,694(7-8):1076-1080
Non-agglomerated hybrid particles of 200 nm diameter with an outer metal oxide shell were prepared by reacting the COOH groups of poly((S)-N-dicarbazolyl-lysine)-covered silica particles with metal alkoxides, such as titanium, zirconium and aluminum alkoxides, followed by sol–gel processing. With tetraethoxysilane (Si(OEt)4), the silica particle core was growing rather than forming an external metal oxide shell, as observed for the other tested metal alkoxides. 相似文献
996.
Tae-Soo You Jing-Tai Zhao Rainer Pttgen Walter Schnelle Ulrich Burkhardt Yuri Grin Gordon J. Miller 《Journal of solid state chemistry》2009,182(9):2430-2442
Two isoelectronic series, Eu(Ga1−xTtx)2 (Tt=Si, Ge, 0≤x≤1), have been synthesized and characterized by powder and single-crystal X-ray diffraction, physical property measurements, and electronic structure calculations. In Eu(Ga1−xSix)2, crystal structures vary from the KHg2-type to the AlB2-type, and, finally, the ThSi2-type structure as x increases. The hexagonal AlB2-type structure is identified for compositions 0.18(2)≤x<0.70(2) with Ga and Si atoms statistically distributed in the polyanionic 63 nets. As smaller Si atoms replace Ga atoms while the number of valence electrons increases, the lattice parameters, unit cell volumes, and Ga–Si distances in this phase region decrease significantly. Although aspects of X-ray diffraction results suggest puckering of the 63 nets for the Si-richest example of the AlB2-type Eu(Ga1−xSix)2, the complete experimental evidence remains inconclusive. On the other hand, in Eu(Ga1−xGex)2, six different structural types were observed as x varies. In addition to EuGa2 (KHg2-type; space group Imma) and EuGe2 (own structure type, space group P3¯m1), the ternary phases studied show four different structures: the AlB2-type for Ga-rich compositions; the YPtAs-type structure for EuGaGe; and two new structures, which are intergrowths of the YPtAs-type EuGaGe and EuGe2, for Ge-rich compositions. These two Ge-rich phases include: (1) Eu(Ga0.45(2)Ge0.55(2))2 containing two YPtAs-type motifs of EuGaGe plus one EuGe2 motif; and (2) Eu(Ga0.40(2)Ge0.60(2))2 containing one YPtAs-type motif alternating with a split site at and z=0.4798(2) with ca. 50% site occupancy by Ga and Ge along the c-axis. Magnetic susceptibilities of three Eu(Ga1−xGex)2 compounds display Curie–Weiss behavior above ca. 100 K, and show effective magnetic moments indicative of divalent Eu with a 4f7 electronic configuration, consistent with. X-ray absorption spectra (XAS). Density of states (DOS) and crystal orbital Hamilton population (COHP) analyses, based on first principles electronic structure calculations, rationalize the observed homogeneity ranges of the AlB2-type phases in both systems and the structural variations as a function of Tt content. 相似文献
997.
Daan Wouters Dr. Stephanie Hoeppener Dr. Ulrich S. Schubert Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(10):1732-1739
Surfaces with purposes : The electroinitiated patterning of self‐assembled monolayers enables the fabrication of a variety of complex nanostructures (see picture). The possibilities offered by the introduction of chemical selectivity through the local generation of chemically active groups and subsequent derivatization are reviewed, with a focus on progress in this area of research over the last four years.
998.
Tetyana Beryozkina Dr. Ksenia Boyko Natalya Khanduyeva Volodymyr Senkovskyy Dr. Marta Horecha Ulrich Oertel Dr. Frank Simon Dr. Manfred Stamm Prof. Anton Kiriy Dr. 《Angewandte Chemie (International ed. in English)》2009,48(15):2695-2698
Graft work : The first surface‐initiated and site‐specific palladium‐catalyzed Suzuki polycondensation that allows selective grafting and patterning of semiconducting and emissive poly[9,9‐bis(2‐ethylhexyl)fluorene] ( 1 ) at room temperature is developed (see scheme). The pattering is demonstrated by AFM (see image).
999.
Simon Reitz Menekse Cebi Philipp Reiß Gregor Studnik Uwe Linne Ulrich Koert Prof. Dr. Lars‐Oliver Essen Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4853-4857
The attachment of modulators to a trimeric porin ion channel was investigated (see picture of the trimer with a crown ether modulator (orange)). The interplay of modulator and protein is essential for the conformational heterogeneity of the hybrid channel. Single‐site attachment in large pores is not sufficient to change the electrophysiological characteristics of the pores—such change requires additional noncovalent interactions or second‐site attachments.
1000.
Lianbing Zhang Avinash J. Patil Dr. Le Li Angelika Schierhorn Dr. Stephen Mann Prof. Ulrich Gösele Prof. Mato Knez Dr. 《Angewandte Chemie (International ed. in English)》2009,48(27):4982-4985
New uses for ALD : By applying standard metal oxide atomic layer deposition (ALD) to two types of porphyrins, site‐specific chemical infiltration of substrate molecules is achieved: Diethylzinc can diffuse into the interior of porphyrin supramolecular structures and induce metalation of the porphyrin molecules from the vapor phase. A=Ph, p‐HO3SC6H4.