全文获取类型
收费全文 | 431篇 |
免费 | 0篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 111篇 |
金属工艺 | 18篇 |
机械仪表 | 3篇 |
建筑科学 | 9篇 |
矿业工程 | 1篇 |
能源动力 | 14篇 |
轻工业 | 46篇 |
无线电 | 40篇 |
一般工业技术 | 66篇 |
冶金工业 | 22篇 |
原子能技术 | 9篇 |
自动化技术 | 88篇 |
出版年
2022年 | 1篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 12篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 30篇 |
2012年 | 21篇 |
2011年 | 38篇 |
2010年 | 25篇 |
2009年 | 28篇 |
2008年 | 30篇 |
2007年 | 21篇 |
2006年 | 19篇 |
2005年 | 20篇 |
2004年 | 14篇 |
2003年 | 10篇 |
2002年 | 10篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 9篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 9篇 |
1988年 | 3篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 8篇 |
1977年 | 4篇 |
1975年 | 1篇 |
1973年 | 5篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1966年 | 1篇 |
排序方式: 共有436条查询结果,搜索用时 15 毫秒
1.
A general model is proposed in order to describe the growth of a deposit by heterogeneous reactions. The hydrodynamics in the fluid is described by a multicomponent transport model for ionic species diluted in a solvent and heat transfer is taken into account in both liquid and solid domains. The boundary condition at the interface where the reaction takes place is described thoroughly. It involves the reaction kinetics and gives access to the velocity of the interface, ie, the mass rate of the solid deposit. The model is then applied to the case of barite crystallization in a heat exchanger. The liquid phase is therefore composed of two ionic species Ba2+ and SO42− diluted in water. The solid phase is modelled as a homogeneous barite deposit. The fully dynamic CFD simulation of the model is made using Comsol Multiphysics, in a cylindrical pipe. The solid growth is analyzed over time and space in terms of the relevant variables of the model. 相似文献
2.
The sociodemographic diversity of residential customers can affect the level of financial risk that an electricity provider experiences in the retail market. To demonstrate the relationship between sociodemographic diversity and financial risk, electricity consumption data drawn from the United Kingdom Power Networks ‘Low Carbon London’ project was analyzed to explore the relationship between sociodemographic diversity and financial risk experienced by electricity retailers. The results show that when increasing the sociodemographic diversity amongst a group of residential customers the effect on financial risk depends on the electricity consumption patterns of individual customers and the relationship of consumption patterns between residential customers. Increasing sociodemographic diversity amongst residential customers with very distinct energy consumption patterns can decrease the overall financial risk associated with the aggregated revenue received from these customers. However, the results showed that adding customers to a customer base without consideration for their sociodemographic background can cause the overall financial risk associated with the aggregated revenue received to change erratically. Whilst previous studies have considered customer diversity and its influence on peak electricity demand, this research advances the state-of-the-art by showing the importance of customer diversity to the financial quantity risk experienced by electricity retailers. This finding has serious implications for electricity providers seeking to mitigate financial risk in the retail electricity market. 相似文献
3.
Sulphonated anthraquinones are known to be recalcitrant to biodegradation and are not eliminated by traditional wastewater treatment plants, leading to their accumulation in fresh water. Due to the high cost and limited efficiency of existing physical-chemical treatments, alternative cheaper processes are required to remove these compounds from industrial effluents. Four plant species were tested under hydroponic conditions for their ability to treat model effluents contaminated with mono- and disulphonated anthraquinones. Among them, Rheum rabarbarum (rhubarb) showed the most promising results and was chosen for further investigation. The apparent transpiration stream concentration factor obtained with this plant species reached up to 2.5, indicating a strong phytotreatment potential that should be further explored then exploited. 相似文献
4.
Taleb Samia Dokhan Nahed Zazi Nacer Chopart Jean-Paul 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(4):781-788
Protection of Metals and Physical Chemistry of Surfaces - In this work the effect of the permanent weak magnetic field on the electrodeposited ZnO nanostructured film on the ITO substrate... 相似文献
5.
Céline Druart Evelyne M. Dewulf Patrice D. Cani Audrey M. Neyrinck Jean-Paul Thissen Nathalie M. Delzenne 《Lipids》2014,49(4):397-402
The aim of this human study was to assess the influence of prebiotic-induced gut microbiota modulation on PUFA-derived bacterial metabolites production. Therefore, we analyzed the circulating fatty acid profile including CLA/CLnA in obese women treated during 3 months with inulin-type fructan prebiotics. In these patients, we had already determined gut microbiota composition by phylogenetic microarray and qPCR analysis of 16S rDNA. Some PUFA-derived bacterial metabolites were detected in the serum of obese patients. Despite the prebiotic-induced modulation of gut microbiota, including changes in CLA/CLnA-producing bacteria, the treatment did not impact significantly on the circulating level of these metabolites. However, some PUFA-derived bacterial metabolites were positively correlated with specific fecal bacteria (Bifidobacterium spp., Eubacterium ventriosum and Lactobacillus spp.) and inversely correlated with serum cholesterol (total, LDL, HDL). These correlations suggest a potential beneficial effect of some of these metabolites but this remains to be confirmed by further investigation. 相似文献
6.
Abstract The autochrome was the first successful commercial colour process. It was invented by Louis and Auguste Lumiere at the tum of the century, patented in 1903 and produced until the 1950s on a sheet film called ‘Filmcolor’. Many articles were published between 1903 when the autochrome process was unveiled to the public, and 1935 when the decline of the screen process began and the first colour films with chromogenic development appeared. There are detailed deseriptions of the plate's range of use, its characteristies and processing, but these publications are very sketchy as to the nature of the components. The most detailed documents, on which this article is based, are the ‘report on the titles and work of Louis Lumiere’ published in 1918, the factory notebooks written by Louis Lumiere or M. Perrigot,1 and the archives of the Lumiere firm, which are now scattered in various locations. 相似文献
7.
8.
This paper deals with the analytically tractable solution for input torques minimisation of two degrees of freedom serial manipulators based on minimum energy control and optimal redistribution of movable masses. The minimisation problem is carried out in two steps: at first, the optimal trajectory of the manipulator is defined as a function, which leads to the minimisation of energy consumption. Then, by introducing the obtained trajectory into dynamic equations, the torques are reduced by using the optimal redistribution of movable masses, which is carried out via an adaptive counterweight system. For this purpose, the torques due to the dynamic loads of the counterweights are presented as a function of the counterweight positions. The conditions for optimal dynamic balancing are formulated by minimisation of the root-mean-square value of the input torque including the dynamic loads of the unbalanced manipulator and counterweights. The suggested approach is illustrated by numerical simulations carried out using ADAMS software. 相似文献
9.
Pascal Laurent Hary Razafindralambo Bernard Wathelet Christophe Blecker Jean-Paul Wathelet Michel Paquot 《Journal of surfactants and detergents》2011,14(1):51-63
Short chemical syntheses were developed to produce a new set of surfactants from uronic acids derived from widely available
raw materials. Three different strategies were used to synthesize uronic amide derivatives, the structures of which were totally
characterized by spectrometric methods (IR, MS, 1H-RMN and 13C-RMN). The best one, using an acid chloride as the synthetic intermediate, furnished the expected amides as a mixture of
anomers in 46–58% global yield. Surface-active properties (CMC, γcmc, Γmax, A
min) of homologous series of uronic acid N-alkylamides from C8 to C18 were also assessed. In general, these sugar-based surfactants exhibited good surface-activities,
and appeared as valuable nonionic surfactants compared to octylphenol 9–10 ethylene oxide condensate, the most well-known
nonionic surfactant. Increasing the alkyl chain length influenced the CMC values for both glucuronic and galacturonic N-alkylamide derivatives. The galacturonic N-alkylamides decreased γcmc at slower values than their counterpart’s glucuronic N-alkylamides. 相似文献
10.
功率因数校正(PFC)电路嵌在交流线路与主电源之间,从交流线路汲入正弦电流,从而提供恒定直流电压。这中间段一般是升压转换器,电感是系统中体积最大且昂贵的元器件之一。在对成本和尺寸敏感的应用中,必须将电感的尺寸和成本降至最低。 相似文献