全文获取类型
收费全文 | 2318篇 |
免费 | 37篇 |
国内免费 | 4篇 |
专业分类
化学 | 1725篇 |
晶体学 | 5篇 |
力学 | 25篇 |
数学 | 325篇 |
物理学 | 279篇 |
出版年
2016年 | 31篇 |
2015年 | 28篇 |
2014年 | 41篇 |
2013年 | 53篇 |
2012年 | 57篇 |
2011年 | 81篇 |
2010年 | 42篇 |
2009年 | 37篇 |
2008年 | 63篇 |
2007年 | 68篇 |
2006年 | 65篇 |
2005年 | 64篇 |
2004年 | 54篇 |
2003年 | 49篇 |
2002年 | 55篇 |
2001年 | 51篇 |
2000年 | 30篇 |
1998年 | 35篇 |
1997年 | 37篇 |
1996年 | 32篇 |
1995年 | 26篇 |
1994年 | 36篇 |
1993年 | 34篇 |
1992年 | 43篇 |
1991年 | 25篇 |
1990年 | 33篇 |
1989年 | 43篇 |
1988年 | 51篇 |
1987年 | 40篇 |
1986年 | 43篇 |
1985年 | 42篇 |
1984年 | 44篇 |
1983年 | 33篇 |
1982年 | 42篇 |
1981年 | 45篇 |
1980年 | 63篇 |
1979年 | 30篇 |
1978年 | 44篇 |
1977年 | 38篇 |
1976年 | 35篇 |
1975年 | 42篇 |
1974年 | 43篇 |
1973年 | 62篇 |
1972年 | 27篇 |
1971年 | 38篇 |
1970年 | 44篇 |
1968年 | 19篇 |
1967年 | 22篇 |
1966年 | 20篇 |
1965年 | 20篇 |
排序方式: 共有2359条查询结果,搜索用时 78 毫秒
1.
Edelsbacher Philipp Redhammer Gnther Monkowius Uwe 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):543-547
Monatshefte für Chemie - Chemical Monthly - Four members of a new series of paddle-wheel copper(II) complexes bearing cyclobutanecarboxylate as bridging ligand with pyridine derived ligands in... 相似文献
2.
Hans‐Peter Brack Denise Ruegg Heinrich Bührer Michal Slaski Selmiye Alkan Günther G. Scherer 《Journal of Polymer Science.Polymer Physics》2004,42(13):2612-2624
The influence of irradiation and grafting on the crystallinity of three base polymers has been investigated with differential scanning calorimetry. Grafting has the largest effect on the base polymer crystallinity and results in a reduction of the crystallinity. The thermal degradation of the base polymers and grafted films has been investigated with thermogravimetric analysis. The extent of the fluorination of the base polymer, the irradiation method, and the graft level all influence the thermal degradation and its activation energy. It is proposed that the variation of the chain lengths of the grafted polystyrene chains is actually a primary underlying factor responsible for the influence of these various parameters on the degradation process. The first results of a comparative thermal analysis of some fuel‐cell membranes are also presented, and the promise and shortcomings of this method are discussed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2612–2624, 2004 相似文献
3.
Werner WinterGünther W.H Höhne 《Thermochimica Acta》2003,403(1):43-53
A method for measuring heat capacities of small samples using a chip-calorimeter and a heat pulse technique is described. The theoretical background to calculate the heat transport properties and the heat capacity of the sample from the pulse response function is given. Problems and potentials of the method are discussed. An example is given. 相似文献
4.
5.
Timur Seidel Alfred Golloch Hans Beerwald Günther Böhm 《Fresenius' Journal of Analytical Chemistry》1993,347(3-4):92-102
Summary A new analytical radiation source combined with fiber optics linked to a diode array detection device with modified software is described. The direct-reading spectrometer simultaneously covers the wavelength range 185–510 nm with a spectral resolution of <1.5 nm. Intense optical emission is observed when positionally stable high-current surface sparks supplied by a pulse-generator with definite discharge parameters (max. 800 Ampere/pulse) are sliding over compact non-conductive materials such as plastics, glasses, quartz filters or powder pellets. Substrate vaporization, ionization and excitation processes in the surface discharge plasma channel generate emission corresponding to neutral and ionic states. The spectra are essentially composed of lines emitted by the electrode material (e.g. copper, silver), from the substrate under investigation, radiation continuum as well as structured background from the surrounding air atmosphere. Due to the occurrence of emission lines of reactive fillers, inorganic pigments and stabilizers, a rapid multi-element screening method is demonstrated. A rapid identification system (mix-up test) of PVC or fire-retardant thermoplastics within one second has been realized from the atomic emission line intensity originating from the sputtered copper electrode material according to its increased volatility in the presence of chlorine (modified Beilstein test).Puls-Plasma-Technik GmbH, Dortmund 相似文献
6.
Jadwiga Frelek Günther Snatzke Wojciech J. Szczepek 《Fresenius' Journal of Analytical Chemistry》1993,345(11):683-687
Summary Bidentate complexes of dimolybdenum tetraacetate with 1,3-diaxial diols show Cotton effects around 490–540 nm (CD band I), 400–440 nm (II), 350–380 nm (III), 320 nm (IV) and 280 nm (V). The sign of the Cotton effect II can be predicted by a proposed sector rule. It seems that from the Cotton effects for cyclic 1,3-diols the absolute configurations or conformations can be obtained.A part of this material was presented at III-rd International Conference on CD Spectroscopy [1] 相似文献
7.
8.
H. Günther M. Foerste M. Kunze G. zu Putlitz U. von Stein 《Zeitschrift für Physik B Condensed Matter》1996,100(4):613-617
We review the previous conclusion [J.Y. Ryu, Y.C. Chung and S.D. Choi, Phys. Rev. B 32, 7769 (1984)] that the trace property Tr(ABC) = Tr(CAB) leads to two different cyclotron transition absorption formulae in the electron-phonon systems in the lowest order approximation. The pictorial expression and the calculated linewidths in Ge and Si show that the socalled EWC scheme is more seeming than the socalled MWC scheme. The difference is expected to disappear if we take into account all the higher order perturbation terms or start with the many body formalism in the complete scheme. 相似文献
9.
10.