全文获取类型
收费全文 | 594篇 |
免费 | 36篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 151篇 |
金属工艺 | 11篇 |
机械仪表 | 12篇 |
建筑科学 | 7篇 |
能源动力 | 45篇 |
轻工业 | 41篇 |
水利工程 | 8篇 |
无线电 | 64篇 |
一般工业技术 | 142篇 |
冶金工业 | 16篇 |
原子能技术 | 6篇 |
自动化技术 | 124篇 |
出版年
2024年 | 3篇 |
2023年 | 8篇 |
2022年 | 13篇 |
2021年 | 33篇 |
2020年 | 31篇 |
2019年 | 29篇 |
2018年 | 31篇 |
2017年 | 32篇 |
2016年 | 20篇 |
2015年 | 19篇 |
2014年 | 34篇 |
2013年 | 54篇 |
2012年 | 46篇 |
2011年 | 36篇 |
2010年 | 38篇 |
2009年 | 31篇 |
2008年 | 35篇 |
2007年 | 35篇 |
2006年 | 19篇 |
2005年 | 14篇 |
2004年 | 13篇 |
2003年 | 7篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有631条查询结果,搜索用时 343 毫秒
51.
Prashant Banerjee 《Journal of Intelligent Manufacturing》1992,3(6):363-378
A framework for enhancement of conceptual tools for rapid computational prototyping of manufacturing entities is presented. A typical manufacturing entity (i.e. manufacturing system and/or individual part) is hierarchically represented in a computer and coupled with applications by dividing its information content into three computational elements: data, drawing and user interface. The information content is divided in this way because each of the above elements has a sufficiently distinct requirement for an efficient computer implementation. Although independent advances have taken place in computer data representation by highly efficient and focused data structures, in drawing representation by sophisticated computer graphics, as well as in user interface by a variety of interface media, these advances cannot be directly utilized in the design of a manufacturing entity unless they are efficiently integrated by relatively small programming effort as is deseribed in this rapid prototyping framework. The framework is implemented in object-oriented programming. A breadth of application areas for the framework is illustrated, and specific details are illustrated with reference to depth in one application area. 相似文献
52.
Eu( Ⅲ ) can be utilized as an indirect electrochemical probe to investigate the interaction of bio-molecules such as DOPA and Dopamine with Ca( Ⅱ ) in vitro. The interaction of DOPA and Dopamine with Eu( Ⅲ )-Eu( Ⅱ ) redox pair was investigated by electrochemical techniques. Both the neurotransmitters are structurally related and undergo interaction with Eu (Ⅲ ). Eu ( Ⅲ ) coordinates with DOPA and Dopamine through five-member chelate tings via carboxylic oxygen and amino nitrogen. The electrode kinetic parameters viz, transfer coefficient (αna), diffusion coefficient (D), forward heterogeneous rate constant ( k^0 fh) were evaluated for Eu( Ⅲ )-DOPA/Eu( Ⅲ )-Dopamine. The results obtained were used to investigate the nature of interaction of Eu (Ⅲ) with muhi-donor biomolecules. The possible mechanism was also proposed. 相似文献
53.
54.
Bordia Prashant; Restubog Simon Lloyd D.; Tang Robert L. 《Canadian Metallurgical Quarterly》2008,93(5):1104
In this article, psychological contract breach, revenge, and workplace deviance are brought together to identify the cognitive, affective, and motivational underpinnings of workplace deviance. On the basis of S. L. Robinson and R. J. Bennett's (1997) model of workplace deviance, the authors proposed that breach (a cognitive appraisal) and violation (an affective response) initiate revenge seeking. Motivated by revenge, employees then engage in workplace deviance. Three studies tested these ideas. All of the studies supported the hypothesized relationships. In addition, self-control was found to be a moderator of the relationship between revenge cognitions and deviant acts; the relationship was weaker for people high in self-control. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Maneesha Gupta Prashant Aggarwal Pritender Singh Naveen Kumar Jindal 《Analog Integrated Circuits and Signal Processing》2009,59(1):97-103
This paper presents an improved low voltage cascode and flipped voltage follower (FVF) based current mirror with the enhancement
of the bandwidth obtained by using a compensation resistor between the gates of the primary transistor pair. In this technique
a carefully determined resistance is used in the diode connected MOS transistor of the current mirror for enhancing the bandwidth.
Active realization of the compensation resistance using MOS operating in the triode region has also been applied to both the
cascode and FVF based current mirror circuits. The proposed circuits have been simulated using PSpice for 0.25 μm CMOS technology
and the obtained results are compared with their uncompensated topologies to show their effectiveness. 相似文献
56.
TiO2 nanotube arrays and particulate films are modified with CdS quantum dots with an aim to tune the response of the photoelectrochemical cell in the visible region. The method of successive ionic layer adsorption and reaction facilitates size control of CdS quantum dots. These CdS nanocrystals, upon excitation with visible light, inject electrons into the TiO2 nanotubes and particles and thus enable their use as photosensitive electrodes. Maximum incident photon to charge carrier efficiency (IPCE) values of 55% and 26% are observed for CdS sensitized TiO2 nanotube and nanoparticulate architectures respectively. The nearly doubling of IPCE observed with the TiO2 nanotube architecture is attributed to the increased efficiency of charge separation and transport of electrons. 相似文献
57.
Prashant S. Kharkar Dr. Angela M. Batman Juan Zhen Dr. Patrick M. Beardsley Prof. Maarten E. A. Reith Prof. Aloke K. Dutta Prof. 《ChemMedChem》2009,4(7):1075-1085
A novel series of optically active molecules based on a 4‐(2‐(benzhydryloxy)ethyl)‐1‐((R)‐2‐hydroxy‐2‐phenylethyl)‐piperidin‐3‐ol template were developed. Depending on stereochemistry, the compounds exhibit various degrees of affinity for three dopamine, serotonin, and norepinephrine transporters. These molecules have the potential for treating several neurological disorders such as drug abuse, depression, and attention deficit hyperactivity disorder.
58.
Stress‐relaxation behavior of glass fiber‐reinforced polyester composites, prepared by a recently developed manufacturing method called rubber pressure molding (RPM), is investigated with special reference to the effect of environmental temperature (−70°C to +100°C), fiber volume fraction (30–60%), and initial load level (1–5 kN). It is found that the stress‐relaxation rate decreases with an increase in the applied load of composites and a decrease in temperature. Below glass transition temperature, the rate of stress relaxation increases with an increase in volume fraction of fibers in the composites, whereas above glass transition temperature, it increases with a decrease in the volume fraction of fibers. The experimental results for a given composites are summarized by four values, the slopes of the two straight lines (two separate relaxation processes), and their intercepts upon the stress axis. Both the slopes are dependent upon the applied load, temperature, and volume fraction of fibers in the composites. Relaxation times in both primary and secondary are calculated over the wide range of temperatures, loads, and volume fraction of fibers in the composites. It depends strongly on the temperature, but does not depend strongly on the applied load and volume fraction of fibers. The performances of the composites are also evaluated through conventional compression‐molding process. The rate of stress relaxation is small when the composites are made of newly proposed RPM technique when compared with the conventional process. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers 相似文献
59.
Kavitha Kumar B. K. Chandrasekhar Sagar Prashant Giribhattanavar Shripad A. Patil 《Microscopy research and technique》2019,82(2):122-127
Drug‐resistant tuberculosis is being increasingly recognized and is one among the leading cause of death worldwide. Remarkable impermeability of cell wall to antituberculous drugs protects the mycobacteria from drug action. The present study analyzed the cell wall thickness among first‐line drug resistant and sensitive Mycobacterium tuberculosis (Mtb) isolated from cerebrospinal fluid by transmission electron microscopy (TEM). The average thickness of the cell wall of sensitive isolates was 13.60 ± 0.98 nm. The maximum difference (26.48%) in the cell wall thickness was seen among multi‐drug resistant (18.50 ± 1.71 nm) isolates and the least difference (4.14%) was shown by streptomycin‐resistant (14.18 ± 1.38 nm) isolates. The ultrastructural study showed evident differences in the cell wall thickness among sensitive and resistant isolates. Preliminary TEM examination of cells indicates that morphological changes occur in the cell wall which might be attributed to the drug resistance. The thickened wall of Mtb appears to help the bacilli to overcome the action of antituberculous drugs. 相似文献
60.
Pahlavan Kaveh Krishnamurthy Prashant 《International Journal of Wireless Information Networks》2021,28(1):3-19
International Journal of Wireless Information Networks - The IEEE 802.11 standard for wireless local area networking (WLAN), commercially known as Wi-Fi, has become a necessity in our day-to-day... 相似文献