全文获取类型
收费全文 | 144篇 |
免费 | 5篇 |
专业分类
化学 | 101篇 |
力学 | 4篇 |
数学 | 19篇 |
物理学 | 25篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2017年 | 2篇 |
2015年 | 5篇 |
2012年 | 12篇 |
2011年 | 11篇 |
2010年 | 6篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 5篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1992年 | 4篇 |
1985年 | 2篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1968年 | 4篇 |
1966年 | 2篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1937年 | 2篇 |
1934年 | 1篇 |
1932年 | 3篇 |
1931年 | 1篇 |
1927年 | 1篇 |
排序方式: 共有149条查询结果,搜索用时 31 毫秒
71.
Carl N. DeSilva Kenneth A. Kline 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1966,17(2):239-249
Zusammenfassung Die Grundgleichungen für eine Theorie der Thermo-Viskoelastizität von Stoffen mit Gedächtnis werden auf das Problem der gradlingen Schichtströmung zwischen zwei Wärmespeichern angewandt. Es werden die Geschwindigkeit, die Spannungen und die Wärmeströmung bestimmt.
Acknowledgement. This work was sponsored by the National Science Foundation under Research Grant NSF GK99. 相似文献
Acknowledgement. This work was sponsored by the National Science Foundation under Research Grant NSF GK99. 相似文献
72.
Cross sections have been measured for the elastic and inelastic scattering of electrons from 70Ge and 72Ge for momentum transfers from 0.65 to 1.14 fm?1. Values for the parameters of a Fermi type ground-state charge distribution were obtained from a phase shift analysis of the elastic cross sections. The rms charge radius corresponding to these parameters is 4.07±0.02 fm for 70Ge and 4.05±0.03 fm for 72Ge. Using DWBA analysis the reduced transition probabilities for the electroexcitation of the 21+ and 31? states were found to be: B(E2, ω)↑ = 19.7±1.2, 26.8±2.0 W.u.; B(E3, ω)↑ = 36±5, 37±7 W.u. for 70Ge and 72Ge respectively. The Jπ = 3? assignments for the state at 2.562 MeV in 70Ge and 2.515 MeV in 72Ge are confirmed. 相似文献
73.
74.
Yan J Delaglio F Kaerner A Kline AD Mo H Shapiro MJ Smitka TA Stephenson GA Zartler ER 《Journal of the American Chemical Society》2004,126(15):5008-5017
Residual dipolar couplings (RDCs), in combination with molecular order matrix calculations, were used to unambiguously determine the complete relative stereochemistry of an organic compound with five stereocenters. Three simple one-dimensional experiments were utilized for the measurements of (13)C-(1)H, (13)C-(19)F, (19)F-(1)H, and (1)H-(1)H RDCs. The order matrix calculation was performed on each chiral isomer independently. The fits were evaluated by the comparison of the root-mean-square deviation (rmsd) of calculated and measured RDCs. The order tensor simulations based on two different sets of RDC data collected with phage and bicelles are consistent. The resulting stereochemical assignments of the stereocenters obtained from using only RDCs are in perfect agreement with those obtained from the single-crystal X-ray structure. Six RDCs are found to be necessary to run the simulation, and seven are the minimum to get an acceptable result for the investigated compound. It was also shown that (13)C-(1)H and (1)H-(1)H RDCs, which are the easiest to measure, are also the most important and information-rich data for the order matrix calculation. The effect of each RDC on the calculation depends on the location of the corresponding vector in the structure. The direct RDC of a stereocenter is important to the configuration determination, but the configuration of stereocenters devoid of protons can also be obtained from analysis of nearby RDCs. 相似文献
75.
P. Demont E. de Haën A. H. Low A. Scheibe C. Carrez R. Kaack A. Eichstädt R. Intonti Jod Alkali G. M. Kline S. F. Acrce L. Eynon J. H Lane F. A. Dykins D. T. Englis J. M. Kolthoff J. Fiehe W. Kordatzki Fr. Lucius H. Bredereck W. W. Oppel E. Pinoff V. E. Levine H. Molisch C. Neubergs Anna May Hubbell W. E. Malinowski K. Bernhauer C. I. Kruisheer J. Tillmans Elsie May Widdowson H. C. Hagedorn B. N. Jansen Ch. S. Hanes E. Schmidt M. Atterer H. Schnegg J. Großfeld M. Schnetka H. Fineke C. I. Krnischeer J. J. J. Dingemans S. Byall J. A. Ambler A. P. Briggs 《Analytical and bioanalytical chemistry》1932,90(9-10):382-397
76.
J. van der Lee W. M. Clark L. Kline J. E. Marsh R. de Jersey Fleming-Struthers H. Leffmann Ch. C. Pines B. T. Effinger H. J. Schaeffer F. A. Faught M. Krajĉinović C. A. Adams J. R. Nicholls J. Penzoldt G. Denigés D. D. van Slyke P. Fleury Y. Awad A. Meyer Suzanne Mathey 《Analytical and bioanalytical chemistry》1932,89(9-10):367-371
77.
78.
Jinlei Yao Carly N. Kline Hao Gu Mi Yan Jennifer A. Aitken 《Journal of solid state chemistry》2009,182(9):2579-2586
Mn-doped CuInSe2 compounds (CuIn1−xMnxSe2, x=0.0125–0.20 and Cu1−yIn1−yMn2ySe2, 2y=0.0125–0.60) were synthesized by high-temperature solid-state reactions. Single phase materials with chalcopyrite structure persist up to 0.10 and 0.20 doping for CuIn1−xMnxSe2 and Cu1−yIn1−yMn2ySe2, respectively. The chalcopyrite and sphalerite phases co-exist in the Cu1−yIn1−yMn2ySe2 system for 2y=0.25–0.50. Attempts to introduce greater manganese content, x=0.15–0.20 for CuIn1−xMnxSe2 and 2y=0.60 for Cu1−yIn1−yMn2ySe2, result in partial phase segregation. For the single-phase samples, the lattice parameters of both systems increase linearly with manganese concentration and thus follow Vegard's law. The temperature of the chalcopyrite–sphalerite phase transition is decreased by manganese substitution for all single-phase samples. The bandgap of the materials remains around 0.9 eV. Additionally, the Mn-doped CuInSe2 compounds display paramagnetic behavior, whereas pure CuInSe2 is diamagnetic at 5–300 K. All the CuIn1−xMnxSe2 and Cu1−yIn1−yMn2ySe2 compounds with chalcopyrite structure show antiferromagnetic coupling and measured effective magnetic moments up to 5.8 μB/Mn. 相似文献
79.
Paul C. Kline Hongqiu Zhao Bruce C. Noll Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):o215-o218
The title compound, also known as β‐erythroadenosine, C9H11N5O3, (I), a derivative of β‐adenosine, (II), that lacks the C5′ exocyclic hydroxymethyl (–CH2OH) substituent, crystallizes from hot ethanol with two independent molecules having different conformations, denoted (IA) and (IB). In (IA), the furanose conformation is OT1–E1 (C1′‐exo, east), with pseudorotational parameters P and τm of 114.4 and 42°, respectively. In contrast, the P and τm values are 170.1 and 46°, respectively, in (IB), consistent with a 2E–2T3 (C2′‐endo, south) conformation. The N‐glycoside conformation is syn (+sc) in (IA) and anti (−ac) in (IB). The crystal structure, determined to a resolution of 2.0 Å, of a cocrystal of (I) bound to the enzyme 5′‐fluorodeoxyadenosine synthase from Streptomyces cattleya shows the furanose ring in a near‐ideal OE (east) conformation (P = 90° and τm = 42°) and the base in an anti (−ac) conformation. 相似文献
80.
Paxton WF Baker PT Kline TR Wang Y Mallouk TE Sen A 《Journal of the American Chemical Society》2006,128(46):14881-14888
We have explored the role of electrokinetics in the spontaneous motion of platinum-gold nanorods suspended in hydrogen peroxide (H2O2) solutions that may arise from the bimetallic electrochemical decomposition of H2O2. The electrochemical decomposition pathway was confirmed by measuring the steady-state short-circuit current between platinum and gold interdigitated microelectrodes (IMEs) in the presence of H2O2. The resulting ion flux from platinum to gold implies an electric field in the surrounding solution that can be estimated from Ohm's Law. This catalytically generated electric field could in principle bring about electrokinetic effects that scale with the Helmholtz-Smoluchowski equation. Accordingly, we observed a linear relationship between bimetallic rod speed and the resistivity of the bulk solution. Previous observations relating a decrease in speed to an increase in ethanol concentration can be explained in terms of a decrease in current density caused by the presence of ethanol. Furthermore, we found that the catalytically generated electric field in the solution near a Pt/Au IME in the presence of H2O2 is capable of inducing electroosmotic fluid flow that can be switched on and off externally. We demonstrate that the velocity of the fluid flow in the plane of the IME is a function of the electric field, whether catalytically generated or applied from an external current source. Our findings indicate that the motion of PtAu nanorods in H2O2 is primarily due to a catalytically induced electrokinetic phenomenon and that other mechanisms, such as those related to interfacial tension gradients, play at best a minor role. 相似文献