全文获取类型
收费全文 | 54篇 |
免费 | 0篇 |
专业分类
化学工业 | 5篇 |
机械仪表 | 1篇 |
建筑科学 | 8篇 |
石油天然气 | 1篇 |
无线电 | 20篇 |
一般工业技术 | 5篇 |
冶金工业 | 11篇 |
自动化技术 | 3篇 |
出版年
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 1篇 |
2019年 | 5篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2014年 | 2篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2008年 | 1篇 |
2007年 | 3篇 |
2003年 | 3篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1993年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有54条查询结果,搜索用时 15 毫秒
1.
Bhawani Narayan Satyaprasad P. Senanayak Ankit Jain K. S. Narayan Subi J. George 《Advanced functional materials》2013,23(24):3053-3060
Oligo(p‐phenylenevinylenes) (OPVs) with amphiphilic character are synthesized and their self‐assembly characteristics studied. Careful studies point at two morphologically different states of assemblies, with one being two dimensional sheets and the other as rolled tubes. This is also the first time that self‐assembled sheets are achieved for OPVs. Morphological and photo‐physical studies reveal a unique aggregate to aggregate transition between rolled tubes and two dimensional sheets, which is outlined as a more thermodynamic aggregate. The thermodynamic aggregate (2D sheet) is better ordered and consists of chromophores that are better excitonically coupled. The mobilities of these aggregates are also studied for a field effect transistor device and as expected sheets supersede rolled tubes by a couple of orders. More interestingly, the mobility values obtained for the well ordered chromophores in sheets is three orders higher than any other self‐assembled OPV previously reported. It is hypothesized that the better π interactions enforced by the amphiphilic design and the resultant supramolecular organization is a prime factor for such a remarkable rise in mobilities. 相似文献
2.
Separation studies of four surfactants (nonionic and cationic) were performed on silica high-performance thin-layer chromatographic
plates with various solvent systems. The most useful chromatographic system for the mutual separation of coexisting polyoxyethylene
(20) stearyl ether (C18EO20), cetylpyridinium chloride (CPC), tetradecyl trimethyl ammonium bromide (TTAB) and polyoxyethylene
(9.5), octyl phenyl ether (OPEO9.5) was formamide + 1 M formic acid (50:50 v/v). The nature of ‘H’ and ‘H+’ of formic acid (H–COO−H+) on the mobility of these surfactants was studied. The interference due to the presence of metal cations as impurities on
the resolution of mixture of C18EO20, CPC, TTAB and OPEO9.5 was also examined. The limits of detection of C18EO20, CPC, TTAB
and OPEO9.5 estimated were 0.0620, 0.0310, 0.0625 and 0.0312 μg/zone, respectively. The practical applicability of the proposed
method was tested for the identification of four coexisting surfactants after their separation from the spiked aqueous systems. 相似文献
3.
Showkat A. Bhawani Othman Sulaiman Ziya A. Khan Rokiah Hashim Mohamad N. M. Ibrahim 《Journal of surfactants and detergents》2011,14(2):301-305
The mutual separation of a mixture of cetyltrimethyl ammonium chloride (CTAC), methyl trioctyl ammonium bromide (MTOB), dodecyltrimethyl
ammonium chloride (DTAC), benzyltrimethyl ammonium chloride (BTAC) and tetrabutyl ammonium bromide (TBAB), was achieved on
silica high performance thin layer chromatographic plates using dimethyl sulfoxide with aqueous sodium-l-tartrate dibasic dihydrate as the solvent system. The effect of concentration of sodium-l-tartrate dibasic dihydrate on the mobility of all the five quaternaries was examined. The limit of detection of CTAC, MTOB,
DTAC, BTAC and TBAB was estimated as 0.6, 0.6, 0.3, 0.6 and 0.3 μg/zone, respectively. The method developed was utilized to
identify these surfactants in different spiked water samples after their preliminary separation. 相似文献
4.
R. Anbalagan Bhawani Singh Pradeep Bhargava 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2003,18(4):411
‘Half tunnels,’ which are excavated as overhangs within steep slopes of hard rocks, have an advantage over conventional full tunnels or open excavations in that they involve less cost and time. However, due to a lack of interest and their uncommon occurrence, the design and analysis of half tunnels have remained by and large unexplored. In the present paper, an effort has been made to study some of the half tunnels in the Middle and the Higher Himalaya in India. In addition to studying the geology of half tunnels, rock mass properties pertaining to Q and RMR for the rocks exposed around the half tunnel have been evaluated. The Markland test has been carried out to assess the probability of plane or wedge failures along the slopes in the half tunnel area. The results obtained have been again confirmed by analyzing the data with the help of a computer program
. Both analyses suggest that the wedges are stable and that all the half tunnels analyzed are safe. Finite element analyses for different slopes and spans of half tunnels have been carried out to study the distribution of stresses around half tunnels. The range of maximum tensile stress concentration in the roof of half tunnels for different slopes is suggested. 相似文献
5.
Access to a running wheel combined with restricted feeding produced body weight loss at an equivalent rate in male and female litter-mate rats (Experiment 1). Thus, despite weighing less and running more, females were not more vulnerable to this procedure. When factors influencing weight loss were varied, no sex difference was found in adaptation to a new feeding schedule or in the effect of single versus group housing (Experiment 2). The apparent critical difference was that body weight loss increased running in males but not in females (Experiment 3). In all rats, rapid recovery of body weight occurred when food access was no longer restricted (Experiment 1), suggesting that "activity-based anorexia" is a misnomer for weight loss by rats in a running wheel. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
K Graham KE Leonard R Room TC Wild RO Pihl C Bois E Single 《Canadian Metallurgical Quarterly》1998,93(5):659-676
The present paper describes promising research directions that emerged from a recent international conference on intoxication and aggression and from the scientific literature generally. In this overview, intoxicated aggression is seen as arising from an interactional process involving multiple contributing factors or causes. This model helps to define research directions that can further understanding and prevention. First, the societal/cultural framing of intoxication and aggression exerts a powerful influence on drinking behaviour and needs to be better understood. Another important area for research is the moderating role on alcohol-related aggression of personal factors such as predisposition to aggression and individual differences in expectations about alcohol and aggression. Research on the role of basic pharmacological effects of alcohol in increasing the likelihood of aggressive behaviour is also a critical aspect of understanding intoxicated aggression. Drinking contexts and environments play a considerable role in the relationship between intoxication and aggressive behaviour and need to be better understood. Another critical direction for future research is the study of intoxicated aggression as a process involving the interaction of the person, the situation and the effects of alcohol in natural and experimental settings. Finally, the paper highlights promising directions for research on interventions to prevent intoxicated aggression and violence. 相似文献
7.
In the present study, the diversion tunnel of Tehri Dam in India has been analyzed using finite element procedure. The tunnel is of circular shape from inside, from hydraulic considerations, and of horseshoe shape from outside, to facilitate excavation and construction of the tunnel. In the analysis, the 8-noded parabolic elements have been used and shape functions are chosen as to satisfy the continuity of displacements between the elements and the convergence criterion. A parametric study has been carried out and the results are presented in nondimensional form and are compared with results of conventional analysis of circular cross sections. 相似文献
8.
Chang Abeer Memon Tayab Din Hussain Zahir M. Kalwar Imtiaz Hussain Chowdhry Bhawani Shankar 《Wireless Personal Communications》2019,106(4):1915-1929
Wireless Personal Communications - Matched filtering has found its way in many diverse applications such as communication, signal processing and more. The emphasis of this paper is on the design... 相似文献
9.
Siddiqui Isma Farah Qureshi Nawab Muhammad Faseeh Chowdhry Bhawani Shankar Uqaili Muhammad Aslam 《Wireless Personal Communications》2019,106(1):179-189
Wireless Personal Communications - Smart grid is an autonomous power generation and production system, that includes various energy management sub-systems such as energy efficient resources, smart... 相似文献