全文获取类型
收费全文 | 826篇 |
免费 | 62篇 |
国内免费 | 138篇 |
专业分类
化学 | 530篇 |
晶体学 | 21篇 |
力学 | 46篇 |
综合类 | 23篇 |
数学 | 80篇 |
物理学 | 326篇 |
出版年
2023年 | 4篇 |
2022年 | 24篇 |
2021年 | 14篇 |
2020年 | 22篇 |
2019年 | 20篇 |
2018年 | 27篇 |
2017年 | 41篇 |
2016年 | 23篇 |
2015年 | 29篇 |
2014年 | 41篇 |
2013年 | 48篇 |
2012年 | 39篇 |
2011年 | 56篇 |
2010年 | 54篇 |
2009年 | 52篇 |
2008年 | 73篇 |
2007年 | 53篇 |
2006年 | 53篇 |
2005年 | 52篇 |
2004年 | 40篇 |
2003年 | 31篇 |
2002年 | 31篇 |
2001年 | 34篇 |
2000年 | 27篇 |
1999年 | 11篇 |
1998年 | 6篇 |
1996年 | 3篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1991年 | 6篇 |
1989年 | 5篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 4篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1973年 | 4篇 |
1971年 | 4篇 |
1970年 | 3篇 |
1968年 | 6篇 |
1967年 | 3篇 |
排序方式: 共有1026条查询结果,搜索用时 46 毫秒
1.
Daulbaev O. Isaenko L. I. Bogdzel’ A. A. Lobanov S. I. Krinitsyn P. G. Milkov V. M. Belushkin A. V. 《Crystallography Reports》2022,67(3):464-469
Crystallography Reports - Two LiInSe2 single crystals, grown under different conditions, have been studied. Characteristics of these crystals for neutron detection have been compared using... 相似文献
2.
The solid-liquid interface motion of NaBi(WO4)2 (NBWO) melt crystal growth is observed in an in situ system, in which the whole processes of interface transition from fiat interface and cellular to dendrite are visualized. The spacing of the dendrite under smaller temperature gradient turns out to be larger than that under larger temperature gradient, which is found to be sensitive to the temperature distribution. The mechanism of dendrite growth of NBWO is studied based on the model of the growth units of anion coordination polyhedra. The { 001} face has two apex links, so it shows higher stability and has high growth rate and forms the arm of dendrite, whereas the {010} face has only one apex link, and thus shows relative slower growth rate and firstly forms the branches. 相似文献
3.
In Situ Observation of Skeletal Shape Transition during BaB2O4 Crystal Growth in High-Temperature Solution
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The transition from a fiat solid-liquid interface to a skeletal shape during BaB2O4 (BBO) single crystal growth in Li2B4O7 flux is observed in real time by an optical high-temperature in-situ observation system. The movement of crystal step is also investigated. The observation results demonstrate that the steps propagate along and parallel to the fiat interface when the crystal size is small. Nevertheless, they will ‘bend' close to the face centre if the crystal size becomes greater. Atomic force microscopy reveals that more deposition places near the face centre give rise to the bending of advancing steps and thus the formation of a vicinal interface structure. Measurements of step velocity show that the velocity keeps nearly constant at different moments for one specific step, whereas the step on a newly formed layer advanced faster than that on a previously formed one when the crystal size is larger than 210μm or so. Thus interracial morphological instability occurs and a skeletal interface is obtained. 相似文献
4.
A. V. Novikov D. N. Lobanov A. N. Yablonsky Yu. N. Drozdov N. V. Vostokov Z. F. Krasilnik 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):467
The dependence of photoluminescence spectra of structures with GeSi/Si(0 0 1) self-assembled nanoislands on growth temperature has been investigated. It was shown that the redshift of the island-related photoluminescence peak with a decrease of the growth temperature is associated with suppression of Si diffusion in the islands and an increase of Ge content in them. For the first time a photoluminescence signal from SiGe islands was observed at energies much lower than the Ge band gap. The energy position of the island-related photoluminescence peak is well described by the model of optical transition, which is indirect in real space. The photoluminescence signal at 1.55 μm from GeSi/Si(0 0 1) self-assembled islands was obtained up to room temperature. 相似文献
5.
We analyze the characteristics of a three-frequency spatial parametric soliton formed by virtue of the cascade frequency tripling in quadratic, periodically poled crystals. A variational approach and a method of averaging are developed, which make it possible to describe analytically, with good accuracy, the characteristics of the spatial solitons studied numerically. 相似文献
6.
Kurenkov V. F. Zhelonkina T. A. Ryabysheva N. A. Lobanov F. I. 《Russian Journal of Applied Chemistry》2003,76(8):1310-1314
The influence of single- and double-charged cations on degradation of metal 2-acrylamido-2-methylpropanesulfonate-N-vinylpyrrolidine copolymers in aqueous solutions in the presence of potassium peroxodisulfate, K2S2O8, at 50 and 70°C was studied by viscosimetry. 相似文献
7.
N. N. Lobanov I. S. Popova N. U. Venskovskii 《Russian Journal of Inorganic Chemistry》2006,51(6):960-963
The crystal-chemical properties of lanthanide oxobromotungstates of composition LnWO4Br (Ln = Eu, Gd, Dy, Er, Yb) are studied. The crystal system and space group for the oxobromotungstates are determined. The unit cell parameters are refined. The parameters a, b, c, and V of the LnWO4Br compounds are studied as functions of the atomic number of the lanthanide. Analytical equations are derived to predict unit cell parameters for unsynthesized lanthanide oxobromotungstates of the class in question. 相似文献
8.
EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
9.
Kurenkov V. F. Gogolashvili E. L. Molgacheva I. V. Gaisina A. I. Garipova A. R. Lobanov F. I. 《Russian Journal of Applied Chemistry》2003,76(5):771-774
The efficiency of water pretreatment at heat and electric power plants using low-molecular-weight cationic Praestols (coagulants) in combination with lime, iron sulfate, and flocculant (high-molecular-weight anionic Praestol) was studied. 相似文献
10.