全文获取类型
收费全文 | 68篇 |
免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 11篇 |
金属工艺 | 1篇 |
机械仪表 | 3篇 |
能源动力 | 3篇 |
轻工业 | 1篇 |
无线电 | 17篇 |
一般工业技术 | 18篇 |
冶金工业 | 9篇 |
自动化技术 | 5篇 |
出版年
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 6篇 |
2012年 | 3篇 |
2011年 | 5篇 |
2010年 | 6篇 |
2009年 | 7篇 |
2008年 | 3篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2001年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有69条查询结果,搜索用时 5 毫秒
1.
2.
Natural rubber is one of the most potential electro-active polymers for sensors, actuators, and energy harvesting applications. Enhancing the characteristic properties of polymers by reinforcing with fillers that possess multifunctional attributes have attracted considerable attention. In the present study, barium titanate reinforced natural rubber composite is prepared by using two-roll mill mixing. Afterwards, mechanical, electrical, and electromechanical properties of the composites are extensively analyzed by reinforcing different amounts of barium titanate into the matrix of natural rubber. The fabricated dielectric composite shows excellent properties such as high dielectric constant, low dielectric losses, high dielectric breakdown strength, and extreme stretchability. It is observed that as the filler loading reaches the value of 11 parts per hundred rubber (phr), maximum agglomeration of the particles occurs. Maximum stretchability and highest ratio of dielectric constant to elastic modulus are obtained at 8 phr of barium titanate fillers and at the loading, a maximum actuation strain of 11.24% is achieved. This study provides a simple, economical, and effective method for preparing enhanced mechanical, electrical, and electromechanical properties of natural rubber composites, facilitating the wide applications of dielectric materials as actuators and generators. 相似文献
3.
We investigated the effects of castration and progesterone administration on the three gonadotropin-releasing hormone (GnRH)-encoding mRNAs in sexually mature male tilapia Oreochromis niloticus. In situ hybridization histochemistry was performed using 35S-labeled antisense oligonucleotide probes complementary to salmon-, seabream-, and chicken II-GnRH cDNAs to quantify cellular GnRH mRNA expression in the terminal nerve ganglia (nucleus olfactoretinalis), preoptic area, and midbrain tegmentum of animals castrated for 2 weeks and injected intraperitoneally with sesame oil or progesterone. Castration significantly elevated salmon-GnRH mRNA but not seabream- or chicken II-GnRH mRNA levels. Progesterone treatment had no effect on salmon-, seabream-, or chicken II-GnRH mRNA levels. Comparisons between intact, castrated, and progesterone-treated animals showed no change in the total volume of nucleus olfactoretinalis, cell sizes, and total numbers of cells expressing GnRH mRNA within the midbrain and preoptic area. These results demonstrate that salmon-GnRH but not seabream- or chicken II-GnRH-synthesizing neurons are under a gonadal steroid negative feedback control and that progesterone might not be the main hormone regulating the three GnRH-encoding mRNAs in the male tilapia. 相似文献
4.
Ajeet Kumar Timothy J. Healey 《Computer Methods in Applied Mechanics and Engineering》2010,199(25-28):1805-1815
We present a generalized approach to stability of static equilibria of nonlinearly elastic rods, subjected to general loading, boundary conditions and constraints (of both point-wise and integral type), based upon the linearized dynamics stability criterion. Discretization of the governing equations leads to a non-standard (singular) generalized eigenvalue problem. A new efficient sparse-matrix-friendly algorithm is presented to determine its few left-most eigenvalues, which, in turn, yield stability/instability information. For conservative problems, the eigenvalue problem arising from the linearized dynamics stability criterion is also shown to be equivalent to that arising in the determination of constrained local minima of the potential energy. We illustrate the method with several examples. A novel variational formulation for extensible and unshearable rods is also proposed within the context of one of the example problems. 相似文献
5.
Siew Cheong Au Christopher Leckie Ajeet Parhar Gerard Wong 《International Journal of Network Management》2004,14(2):105-118
As the Internet grows in size and complexity, network managers face a significant challenge in trying to understand the behaviour of routing protocols in large networks. In this paper, we present a tool called VLNT (visualizing large network topologies), which helps network managers to analyse complex routing topologies. A key contribution of our system is a novel hybrid layout algorithm, which significantly reduces the computation time required to layout large network topologies in comparison to conventional layout approaches. In addition our algorithm includes a novel termination criterion that avoids unnecessary iterations when optimizing the network layout. We demonstrate how the visualization features of VLNT can be used to analyse and improve BGP routing topologies, and provide examples using real‐life routing data. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
6.
7.
Sharif Ahmad Ufana Riaz Ajeet Kaushik Javed Alam 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(3):355-360
The present study reports a facile technique for the synthesis of crystalline super paramagnetic nano ferrite (Fe3O4) particles using diethyl amine as a soft template. The spectral properties of Fe3O4 nanoparticles were characterized by UV–visible and Fourier Transform Infrared (FTIR) spectroscopies while the crystalline
structure and particle size was estimated using X-Ray diffraction (XRD) as well as transmission electron microscopy (TEM)
techniques. The super paramagnetic behavior of Fe3O4 nanoparticles was determined using vibrating sample magnetometer (VSM) at 300 K. The results of the studies revealed that
this technique could be adopted to synthesize agglomerate free super paramagnetic Fe3O4 nanoparticles which may find potential application in the filed of biosensor and corrosion protective coatings. 相似文献
8.
9.
Barik A Solanki PR Kaushik A Ali A Pandey MK Kim CG Malhotra BD 《Journal of nanoscience and nanotechnology》2010,10(10):6479-6488
Cholesterol oxidase (ChOx) has been covalently immobilized onto polyaniline-carboxymethyl cellulose (PANI-CMC) nanocomposite film deposited onto indium-tin-oxide (ITO) coated glass plate using glutaraldehyde as a cross-linker. Fourier transform infrared (FTIR) spectroscopic and electrochemical studies have been used to characterize the PANI-CMC/ITO nanocomposite electrode and ChOx/PANI-CMC/ITO bioelectrode. Scanning electron microscopy (SEM) studies reveal the formation of PANI-CMC nanocomposite fibers of size approximately 150 nm in diameter. The ChOx/PANI-CMC/ITO bioelectrode exhibits linearity as 0.5-22 mM, detection limit as 1.31 mM, sensitivity as 0.14 mA/mM cm2, response time as 10 s and shelf-life of about 10 weeks when bioelectrode is stored at 4 degrees C. The low value of Michaelis-Menten constant (K(m)) obtained as 2.71 mM reveals high affinity of immobilized ChOx for PANI-CMC/ITO nanocomposite electrode. 相似文献
10.
The aim of this paper is to evaluate and validate the average value of national or secondary standard of DC voltage, using four different methods; comparison, substitution, difference and ratio method. In the paper the custom made automation program developed to control the whole measurement process is discussed as well. The automation system has been developed in the view of achieving maximal quality of metrological performance i.e. minimum measurement uncertainty and maximum reliability. It is found that measurement automation provides reliable and efficient way for the calibration of Zener based standard of DC voltage. 相似文献