首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   136篇
  免费   4篇
  国内免费   1篇
化学   50篇
力学   2篇
数学   52篇
物理学   37篇
  2023年   1篇
  2022年   2篇
  2021年   4篇
  2020年   3篇
  2019年   3篇
  2018年   4篇
  2017年   4篇
  2016年   6篇
  2015年   8篇
  2014年   8篇
  2013年   7篇
  2012年   5篇
  2011年   11篇
  2010年   6篇
  2009年   4篇
  2008年   8篇
  2007年   6篇
  2005年   4篇
  2004年   4篇
  2003年   9篇
  2002年   7篇
  2001年   6篇
  2000年   4篇
  1999年   2篇
  1998年   2篇
  1997年   1篇
  1994年   1篇
  1982年   2篇
  1981年   1篇
  1979年   1篇
  1978年   2篇
  1977年   1篇
  1976年   2篇
  1960年   2篇
排序方式: 共有141条查询结果,搜索用时 453 毫秒
21.
The method elaborated in [1] is applied to the solution of some problems for a plane lattice and the linear chain. The method can be used to investigate deformations around crystal lattice defects.
, [1] . .
  相似文献   
22.
The theory of the discrete Fourier transform [1], [2] is applied in solving a system of difference equations describing the positions of atoms in a deformed crystal lattice. The crystal lattice is approximated by the Born-Kármán model modified to include the internal energy of the undeformed crystal.
, , , [1] [2]. - , , .
  相似文献   
23.
Doklady Mathematics - Let $${{V}_{r}}({{\mathbb{R}}^{n}})$$, n ≥ 2, be the set of functions $$f \in {{L}_{{{\text{loc}}}}}({{\mathbb{R}}^{n}})$$ with zero integrals over all balls in...  相似文献   
24.
We obtain new sufficient conditions under which a set on the plane has the Pompeiu property. This result allows us to construct first examples of domains with the Pompeiu property with non-Lipschitz (and even fractal) boundary. In addition, we study the problem of determining the least radius of the ball on the sphere in which a given set is a Pompeiu set. We obtain the solution of this problem in the case of a biangle and a spherical half-disk. We also consider some applications to questions of complex analysis.  相似文献   
25.
26.
The purpose of this work was to evaluate the new bone tissue, comparing two different carriers for rhBMP-2, monoolein and chitosan gels, using the decortication and nondecorticatication surgical technique in rat mandibles, evaluated by histomorphometrical method. It was used 56 male Wistar rats (300g), divided into 8 groups according to the rhBMP-2 carrier used, monoolein or chitosan gels; surgical technique, bone decortication or nondecortication; and period of time, 3 or 6 weeks until the sacrifice by perfusion. Results obtained in this study showed that the rhBMP-2/monoolein and rhBMP-2/chitosan used in this experimental model was able to induce osteogenesis, contributing to the bone healing process. The bone repair process was time dependent, so that at 6 weeks there was an improved amount of new bone in relation to 3 weeks, considered each analyzed group, and the decortication was able to expose the bone marrow and speed up the bone healing process, which was showed by histomorphometrical methods. Both of carriers were capable to adapt to the bone surgical area, according to the clinical observations, and had favorable properties in relation to protein releasing, revealed by the amount of new bone tissue found in the histological analysis.  相似文献   
27.
Hot rolling is an essential industrial process in the production of sheet steel, a widely used product in manufacturing and construction. A finishing mill performs a set of operations in a hot strip rolling mill, and is a complex unit including many processes and control loops. Its modelling is a challenging task due to the variety of phenomena that occur within the mill, and variable transport delays. Model validation is also challenging due to a scarcity of measurements. On the other hand, a dynamic model that adequately reflects the numerous interactions between the mill units can be very useful for tasks such as high performance control design or vibration analysis. In this study, a one-dimensional model has been developed and validated against real plant data. The end use of the model is intended to be looper control analysis, but the model is kept sufficiently general so that it can be used or easily extended for other applications.  相似文献   
28.
The class of functions with zero integrals over all balls of one fixed radius on the complex hyperbolic space is described. Translated fromMatematicheskie Zametki, Vol. 68, No. 4, pp. 504–512, October, 2000.  相似文献   
29.
The use of hot-stage Raman microscopy — the direct coupling of Raman spectroscopy and thermomicroscopy — is demonstrated for the drug substances paracetamol and lufenuron.Paracetamol is a well-known analgesic and antipyretic drug, for which three polymorphic forms are currently known. Lufenuron is a benzoylphenyl urea derivative that has been classified as a chitin synthesis inhibitor. It is indicated for the use in pets for the prevention and control of flea population and used in crop protection for the control of Lepidoptera, Western Flower thrips and rust mites. It is the first time that the polymorphism of lufenuron is addressed. All known modifications of paracetamol and lufenuron were produced and identified by hot-stage Raman microscopy. A close correlation of thermal and spectroscopic information was achieved by this combination of techniques.For lufenuron a series of new polymorphic forms were found and characterized. Raman spectroscopy allowed to identify the thermodynamic stable form A as the one which is marketed in tablets.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
30.
Journal of Analytical Chemistry - The drift time and ion mobility of imidazole are determined and a procedure for the mathematical processing of spectra is developed. The specific features of...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号