全文获取类型
收费全文 | 128篇 |
免费 | 0篇 |
国内免费 | 9篇 |
专业分类
化学 | 19篇 |
力学 | 5篇 |
数学 | 23篇 |
物理学 | 90篇 |
出版年
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2017年 | 2篇 |
2016年 | 9篇 |
2015年 | 1篇 |
2014年 | 38篇 |
2013年 | 24篇 |
2012年 | 18篇 |
2011年 | 13篇 |
2010年 | 1篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2002年 | 2篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1974年 | 1篇 |
1963年 | 2篇 |
1960年 | 1篇 |
排序方式: 共有137条查询结果,搜索用时 0 毫秒
1.
The reflection of three-dimensional(3D) plane waves in a highly anisotropic(triclinic) medium under the context of generalized thermoelasticity is studied. The thermoelastic nature of the 3D plane waves in an anisotropic medium is investigated in the perspective of the three-phase-lag(TPL), dual-phase-lag(DPL), Green-Naghdi-III(GNIII), Lord-Shulman(LS), and classical coupled(CL) theories. The reflection coefficients and energy ratios for all the reflected waves are obtained in a mathematical form. The rotational effects on the reflection characteristics of the 3D waves are discussed under the context of generalized thermoelasticity. Comparative analyses for the reflection coefficients of the waves among these generalized thermoelastic theories are performed. The energy ratios for each of the reflected waves establish the energy conservation law in the reflection phenomena of the plane waves. The highly anisotropic materials along with the rotation may have a significant role in the phenomenon of the reflection behavior of the 3D waves. Numerical computations are performed for the graphical representation of the study. 相似文献
2.
The feasibility study for searching neutrinoless double beta decay in 124Sn using cryogenic bolometer has been initiated. For this purpose, a custom-built cryogen-free dilution refrigerator, having a large cooling power of 1.4 mW at 120 mK, has been installed at TIFR, India. This paper describes the design, installation and performance of a cryogen-free dilution refrigerator (CFDR-1200). The performance of CFDR-1200 has been analysed using Takano’s model developed for conventional (wet) dilution refrigerators. 相似文献
3.
4.
5.
Resonance width, shift in resonance frequency, relaxation time and activation energy of 5CB nematic liquid crystal are measured
using microwave cavity technique under the influence of an external magnetic field at 9 GHz and at different temperatures.
The dielectric response in liquid crystal at different temperatures and the effects of applied magnetic field on transition
temperatures are studied in the present work. The technique needs a small quantity (< 0.001 cm3) of the sample and provides fruitful information about the macroscopic structure of the liquid crystal. 相似文献
6.
The paper investigates synchronization in unidirectionally coupled dynamical systems wherein the influence of drive on response is cumulative: coupling signals are integrated over a time interval τ. A major consequence of integrative coupling is that the onset of the generalized and phase synchronization occurs at higher coupling compared to the instantaneous (τ?=?0) case. The critical coupling strength at which synchronization sets in is found to increase with τ. The systems explored are the chaotic Rössler and limit cycle (the Landau–Stuart model) oscillators. For coupled Rössler oscillators the region of generalized synchrony in the phase space is intercepted by an asynchronous region which corresponds to anomalous generalized synchronization. 相似文献
7.
PRASHANT SINGH RUDRA BANERJEE MOSHIOUR RAHAMAN A V RUBAN BIPLAB SANYAL ABHIJIT MOOKERJEE 《Pramana》2011,76(4):639-656
We study the electronic structure and a mean-field phase analysis based on the pair–pair energies derived from first-principles
electronic structure calculations of AuFe and NiMo alloys. We have used the tight-binding linear muffin-tin orbitals-based
augmented space recursion (TB-LMTO-ASR) method to do so. We investigate different behaviours of the two alloy systems by mapping
the problems onto equivalent Ising models and then discuss the magnetic phase diagrams using the calculated pair energies.
All three phases: paramagnetic, random ferromagnetic and spin glass, have been studied. 相似文献
8.
Primordial black holes evaporate due to Hawking radiation. We find that the evaporation times of primordial black holes increase
when accretion of radiation is included. Thus, depending on accretion efficiency, more primordial black holes are existing
today, which strengthens the conjecture that the primordial black holes are the proper candidates for dark matter. 相似文献
9.
We study the interplay of topology and dynamics of excitable nodes on random networks. Comparison is made between systems
grown by purely random (Erdős–Rényi) rules and those grown by the Achlioptas process. For a given size, the growth mechanism
affects both the thresholds for the emergence of different structural features as well as the level of dynamical activity
supported on the network. 相似文献
10.
Trace elements have been at the focus of attention for decades with considerable emphasis on their role in biology and biomedical
sciences, environmental sciences, geology, archaeology and material sciences. They comprise a large number of elements, some
having essential physiological functions, whereas others are toxic, mutagenic or carcinogenic. A few even have antiproliferative
and anticarciniogenic properties. The advent of various instrumental techniques and sophisticated instrumentations has made
their detection to very low limits possible, making this a very important multidisciplinary study. Among these techniques
the energy-dispersive X-ray fluorescence (EDXRF) technique is being widely used for trace element detection in various fields
of science. Keeping the importance of trace elements in mind, the Kolkata centre of UGC-DAE Consortium for Scientific Research
initiated several research schemes in different fields of trace element research using various techniques, EDXRF being one
of the main techniques. A Xenemetrix (erstwhile Jordan Valley) EX 3600 EDXRF spectrometer is being used to carry out the research.
This presentation aims to highlight some of the very recent applications of EDXRF in the study of the role of trace elements
in pre-cancerous tissues, medicinal plants and also in some environmental studies. 相似文献