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排序方式: 共有87条查询结果,搜索用时 17 毫秒
71.
Altmeier M Bauer F Bisplinghoff J Busch M Busser K Colberg T Demirors L Diehl O Engelhardt HP Eversheim PD Felden O Gebel R Glende M Greiff J Hinterberger F Jonas E Krause H Lindemann T Lindlein J Maier R Maschuw R Meinerzhagen A Prasuhn D Rohdjess H Rosendaal D von Rossen P 《Physical review letters》2000,85(9):1819-1822
Excitation functions A(N)(p(p),Theta(c.m.)) of the analyzing power in pp--> elastic scattering have been measured with a polarized atomic hydrogen target for projectile momenta p(p) between 1000 and 3300 MeV/ c. The experiment was performed for scattering angles 30 degrees =Theta(c.m.)=90 degrees using the recirculating beam of the proton storage ring COSY during acceleration. The resulting excitation functions and angular distributions of high internal consistency have significant impact on the recent phase shift solution SAID SP99, in particular, on the spin triplet phase shifts between 1000 and 1800 MeV, and demonstrate the limited predictive power of single-energy phase shift solutions at these energies. 相似文献
72.
Bernd Giese Stephan Wessely Martin Spormann Ute Lindemann Eric Meggers Maria E. Michel-Beyerle 《Angewandte Chemie (International ed. in English)》1999,38(7):996-998
Hopping between bases of similar redox potentials is the mechanism by which charge transport occurs through DNA. This was shown by rate measurements performed with double strands 1 – 3 . This mechanism explains why hole transfer displays a strong sequence dependence, and postulates that electron transfer in unperturbed DNA should not be dependent on the sequence. 相似文献
73.
Inge Lindemann Roger Domènech Ferrer Dr. Lothar Dunsch Prof. Dr. Yaroslav Filinchuk Dr. Radovan Černý Dr. Hans Hagemann Dr. Vincenza D'Anna Latévi Max Lawson Daku Dr. Ludwig Schultz Prof. Dr. Oliver Gutfleisch Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(29):8707-8712
The new double‐cation Al–Li–borohydride is an attractive candidate material for hydrogen storage due to a very low hydrogen desorption temperature (~70 °C) combined with a high hydrogen density (17.2 wt %). It was synthesised by high‐energy ball milling of AlCl3 and LiBH4. The structure of the compound was determined from image‐plate synchrotron powder diffraction supported by DFT calculations. The material shows a unique 3D framework structure within the borohydrides (space group=P‐43n, a=11.3640(3) Å). The unexpected composition Al3Li4(BH4)13 can be rationalized on the basis of a complex cation [(BH4)Li4]3+ and a complex anion [Al(BH4)4]?. The refinements from synchrotron powder diffraction of different samples revealed the presence of limited amounts of chloride ions replacing the borohydride on one site. In situ Raman spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TG) and thermal desorption measurements were used to study the decomposition pathway of the compound. Al–Li–borohydride decomposes at ~70 °C, forming LiBH4. The high mass loss of about 20 % during the decomposition indicates the release of not only hydrogen but also diborane. 相似文献
74.
Sahli H. Bechhold E. Salkowski Jos Bilinski B. Wagner H. Citron Rudolf Adler Oscar Adler Ad. Jolles C. Neuberg Wilh Neimann B. Tollens V. Frommer Lindemann Ludw E. Nicolas A. Gürber Martin Krüger Jul Schmidt Fr. W. Schildbach Alex Raphael E. Abderhalden Fr. Pregl Paul Ehrlich O. Neubauer Rich Bauer Erwin Rohde und E. Voisenet 《Fresenius' Journal of Analytical Chemistry》1906,45(5-6):397-404
Ohne Zusammenfassung 相似文献
75.
Cover Picture: Photoinduced Charge‐Carrier Generation in Epitaxial MOF Thin Films: High Efficiency as a Result of an Indirect Electronic Band Gap? (Angew. Chem. Int. Ed. 25/2015) 下载免费PDF全文
Dr. Jinxuan Liu Wencai Zhou Jianxi Liu Dr. Ian Howard Dr. Goran Kilibarda Dr. Sabine Schlabach Damien Coupry Dr. Matthew Addicoat Satoru Yoneda Yusuke Tsutsui Dr. Tsuneaki Sakurai Prof. Dr. Shu Seki Dr. Zhengbang Wang Peter Lindemann Dr. Engelbert Redel Prof. Thomas Heine Prof. Dr. Christof Wöll 《Angewandte Chemie (International ed. in English)》2015,54(25):7201-7201
76.
W Lindemann 《The Journal of the Acoustical Society of America》1986,80(6):1623-1630
This paper explains the "law of the first wave front" and related binaural phenomena on the basis of the model presented in the previous paper [Lindemann, J. Acoust. Soc. Am. 80, 1608-1622 (1986)] in which a contralateral inhibition mechanism was added to the well-known model of binaural cross correlation. In order to verify the predictions of the extended model, psychoacoustic experiments were performed with pairs of narrow-band impulses which were presented through headphones. The test signals consisted of a diotic primary sound and an "echo" with an interaural arrival-time difference. Lateralization was measured as a function of the time delay between primary sound and echo. For delays below the echo threshold, summing localization and the law of the first wave front were simulated; for delays above the echo threshold, the model predicts an influence of the primary sound on the lateralization of the echo. 相似文献
77.
Werner E. Morf Marin Huser Bernhard Lindemann Peter Schulthess Wilhelm Simon 《Helvetica chimica acta》1986,69(6):1333-1342
Selective transport of given substrates through artificial membranes can be achieved by incorporation of electrically neutral or charged carriers. Such mediated transport described for alkali and alkaline-earth metal cations is reported here for the first time for certain anions using cobyrinate-type ionophores, and it is also conceivable to be realized for nonionic substrates (e.g. glucose). The fundamental requirements for corresponding co-transport and counter-transport membrane systems are set forth in view of a design of novel substrate-selective sensors for analytical-chemical applications. 相似文献
78.
79.
Kratochwil NA Malherbe P Lindemann L Ebeling M Hoener MC Mühlemann A Porter RH Stahl M Gerber PR 《Journal of chemical information and modeling》2005,45(5):1324-1336
G protein-coupled receptors (GPCRs) share a common architecture consisting of seven transmembrane (TM) domains. Various lines of evidence suggest that this fold provides a generic binding pocket within the TM region for hosting agonists, antagonists, and allosteric modulators. Here, a comprehensive and automated method allowing fast analysis and comparison of these putative binding pockets across the entire GPCR family is presented. The method relies on a robust alignment algorithm based on conservation indices, focusing on pharmacophore-like relationships between amino acids. Analysis of conservation patterns across the GPCR family and alignment to the rhodopsin X-ray structure allows the extraction of the amino acids lining the TM binding pocket in a so-called ligand binding pocket vector (LPV). In a second step, LPVs are translated to simple 3D receptor pharmacophore models, where each amino acid is represented by a single spherical pharmacophore feature and all atomic detail is omitted. Applications of the method include the assessment of selectivity issues, support of mutagenesis studies, and the derivation of rules for focused screening to identify chemical starting points in early drug discovery projects. Because of the coarseness of this 3D receptor pharmacophore model, however, meaningful scoring and ranking procedures of large sets of molecules are not justified. The LPV analysis of the trace amine-associated receptor family and its experimental validation is discussed as an example. The value of the 3D receptor model is demonstrated for a class C GPCR family, the metabotropic glutamate receptors. 相似文献
80.
Katrin Kittler Holger Hoffmann Franziska Lindemann Matthias Koch Sascha Rohn Ronald Maul 《Analytical and bioanalytical chemistry》2014,406(24):5765-5774
Cylindrospermopsin (CYN) is a cyanobacterial toxin associated with human and animal poisonings. Due to its toxicity in combination with its widespread occurrence, the development of reliable methods for selective, sensitive detection and accurate quantification is mandatory. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis using stable isotope dilution analysis (SIDA) represents an ideal tool for this purpose. U-[15N5]-CYN was synthesized by culturing Aphanizomenon flos-aquae in Na15NO3-containing cyanobacteria growth medium followed by a cleanup using graphitized carbon black columns and mass spectrometric characterization. Subsequently, a SIDA-LC-MS/MS method for the quantification of CYN in freshwater and Brassica matrices was developed showing satisfactory performance data. The recovery ranged between 98 and 103 %; the limit of quantification was 15 ng/L in freshwater and 50 μg/kg dry weight in Brassica samples. The novel SIDA was applied for CYN determination in real freshwater samples as well as in kale and in vegetable mustard exposed to toxin-containing irrigation water. Two of the freshwater samples taken from German lakes were found to be CYN-contaminated above limit of quantification (17.9 and 60.8 ng/L). CYN is systemically available to the examined vegetable species after exposure of the rootstock leading to CYN mass fractions in kale and vegetable mustard leaves of 15.0 μg/kg fresh weight and 23.9 μg/kg fresh weight, respectively. CYN measurements in both matrices are exemplary for the versatile applicability of the developed method in environmental analysis. 相似文献