全文获取类型
收费全文 | 539篇 |
免费 | 8篇 |
专业分类
化学 | 263篇 |
晶体学 | 6篇 |
力学 | 12篇 |
数学 | 19篇 |
物理学 | 247篇 |
出版年
2023年 | 3篇 |
2021年 | 5篇 |
2020年 | 10篇 |
2018年 | 3篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 24篇 |
2012年 | 21篇 |
2011年 | 33篇 |
2010年 | 11篇 |
2009年 | 11篇 |
2008年 | 25篇 |
2007年 | 24篇 |
2006年 | 30篇 |
2005年 | 22篇 |
2004年 | 23篇 |
2003年 | 21篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 6篇 |
1995年 | 15篇 |
1994年 | 14篇 |
1993年 | 22篇 |
1992年 | 15篇 |
1991年 | 15篇 |
1990年 | 15篇 |
1989年 | 13篇 |
1988年 | 8篇 |
1987年 | 3篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 10篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1975年 | 6篇 |
1974年 | 4篇 |
1970年 | 2篇 |
1966年 | 2篇 |
1958年 | 2篇 |
1928年 | 2篇 |
1917年 | 3篇 |
排序方式: 共有547条查询结果,搜索用时 15 毫秒
71.
72.
H. Gabelmann J. Münzel B. Pfeiffer G. I. Crawford H. Wollnik K. -L. Kratz 《Zeitschrift für Physik A Hadrons and Nuclei》1982,308(4):359-360
Beta-delayed neutron emission probabilities (Pn) of short-lived Sr, Y, Ba and La precursors were measured. As expected from systematics, but in disagreement with recent data from the SOLIS-group, only small Pn -values were obtained. 相似文献
73.
The hydrogen vibrational modes in LaHx samples have been investigated by pulsed neutron spectroscopy. The results are compared with a simple model emphasizing strong HH forces and the lack of stoichiometry in LaH2.28. 相似文献
74.
B. Roussière F. Le Blanc J. Pinard L. Cabaret J. Crawford H. T. Duong J. Genevey G. Huber F. Ibrahim M. Krieg J. K. P. Lee J. Obert J. Oms J. C. Putaux C. Richard-Serre J. Sauvage V. Sebastian 《Acta Physica Hungarica A》1998,7(1):97-100
Isotope shift and hyperfine structure measurements have been performed on the short lived184Au nucleus using the COMPLIS apparatus installed at ISOLDE. The charge radius change and the magnetic and quadrupole moments of both isomeric and ground states have been deduced. The184Au ground state appears to be slightly more deformed than the isomeric state. 相似文献
75.
K. -L. Kratz H. Ohm H. Gabelmann G. I. Crawford G. Jung B. Pfeiffer 《Zeitschrift für Physik A Hadrons and Nuclei》1982,305(1):93-94
Beta-delayed neutron measurements on95Rb have indicated evidence for two heretofore unknown excited O+ states in94Sr which are not fed by ß -decay from the Jπ = 3? ground state of94Rb. 相似文献
76.
77.
Tasić U Alexeev Y Vayner G Crawford TD Windus TL Hase WL 《Physical chemistry chemical physics : PCCP》2006,8(40):4678-4684
Ab initio calculations at the CCSD(T)/aug-cc-pVTZ level of theory were used to characterize the Ar-CH(3)OH intermolecular potential energy surface (PES). Potential energy curves were calculated for four different Ar + CH(3)OH orientations and used to derive an analytic function for the intermolecular PES. A sum of Ar-C, Ar-O, Ar-H(C), and Ar-H(O) two-body potentials gives an excellent fit to these potential energy curves up to 100 kcal mol(-1), and adding an additional r(-n) term to the Buckingham two-body potential results in only a minor improvement in the fit. Three Ar-CH(3)OH van der Waals minima were found from the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVTZ calculations. The structure of the global minimum is in overall good agreement with experiment (X.-C. Tan, L. Sun and R. L. Kuczkowski, J. Mol. Spectrosc., 1995, 171, 248). It is T-shaped with the hydroxyl H-atom syn with respect to Ar. Extrapolated to the complete basis set (CBS) limit, the global minimum has a well depth of 0.72 kcal mol(-1) with basis set superposition error (BSSE) correction. The aug-cc-pVTZ basis set gives a well depth only 0.10 kcal mol(-1) smaller than this value. The well depths of the other two minima are within 0.16 kcal mol(-1) of the global minimum. The analytic Ar-CH(3)OH intermolecular potential also identifies these three minima as the only van der Waals minima and the structures predicted by the analytic potential are similar to the ab initio structures. The analytic potential identifies the same global minimum and the predicted well depths for the minima are within 0.05 kcal mol(-1) of the ab initio values. Combining this Ar-CH(3)OH intermolecular potential with a potential for a OH-terminated alkylthiolate self-assembled monolayer surface (i.e., HO-SAM) provides a potential to model Ar + HO-SAM collisions. 相似文献
78.
Veenu Bala Yashpal S. Chhonker Richard L. Sleightholm Ayrianne J. Crawford Michael A. Hollingsworth Daryl J. Murry 《Biomedical chromatography : BMC》2020,34(8):e4859
A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (MS/MS) method was developed and validated for the quantitation of the novel CDK5 inhibitor ‘20–223' in mouse plasma. Separation of analytes was achieved by a reverse-phase ACE Excel C18 column (1.7 μm, 100 × 2.1 mm) with gradient elution using 0.1% formic acid (FA) in methanol and 0.1% FA as the mobile phase. Analytes were monitored by MS/MS with an electrospray ionization source in the positive multiple reaction monitoring mode. The MS/MS response was linear over the concentration range 0.2–500 ng/mL for 20–223. The within- and between-batch precision were within the acceptable limits as per Food and Drug Administration guidelines. The validated method was successfully applied to plasma protein binding and in vitro metabolism studies. Compound 20–223 was highly bound to mouse plasma proteins (>98% bound). Utilizing mouse S9 fractions, in vitro intrinsic clearance (CLint) was 24.68 ± 0.99 μL/min/mg protein. A total of 12 phase I and II metabolites were identified with hydroxylation found to be the major metabolic pathway. The validate method required a low sample volume, was linear from 0.2 to 500 ng/mL, and had acceptable accuracy and precision. 相似文献
79.
H. Mühe Mc. Candless E. Valenta Utz Wilh Vaubel B. Ahlström O. Aschan J. Kondakow J. Schindelmeiser R. Böhme H. Herzfeld J. E. Teeple R. Adan J. Marcusson Darmois H. Wolff C. Piest R. Marcille EA. Parry M. Adams H. W. Fosse K. Ihnatowzcz 《Analytical and bioanalytical chemistry》1917,56(10-11):541-560
80.
Summary Improved analytical procedures are presented for the simultaneous determination of carbon, hydrogen, and nitrogen in solid organic materials by the gas volumetric method. The accuracy is improved, and the method is less dependent upon the analyst's technique.
Work was performed under the auspices of the U. S. Atomic Energy Commission. 相似文献
Zusammenfassung Verbesserte Verfahren für die gleichzeitige gasvolumetrische Bestimmung von Kohlenstoff, Wasserstoff und Stickstoff in festen organischen Verbindungen werden beschrieben. Die Genauigkeit wurde verbessert, und die Ergebnisse sind weniger von der Arbeitstechnik des Analytikers abhängig.
Résumé On présente une amélioration des procédés analytiques pour le dosage simultané du carbone, de l'hydrogène et de l'azote dans les matériaux solides organiques par la méthode volumétrique gazeuse. La précision est meilleure et la méthode dépend moins de la technique de l'analyste.
Work was performed under the auspices of the U. S. Atomic Energy Commission. 相似文献