全文获取类型
收费全文 | 182篇 |
免费 | 10篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 7篇 |
综合类 | 2篇 |
化学工业 | 56篇 |
金属工艺 | 4篇 |
机械仪表 | 1篇 |
建筑科学 | 3篇 |
能源动力 | 5篇 |
轻工业 | 28篇 |
无线电 | 18篇 |
一般工业技术 | 51篇 |
冶金工业 | 4篇 |
自动化技术 | 16篇 |
出版年
2023年 | 4篇 |
2022年 | 16篇 |
2021年 | 7篇 |
2020年 | 11篇 |
2019年 | 13篇 |
2018年 | 16篇 |
2017年 | 10篇 |
2016年 | 12篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 8篇 |
2012年 | 7篇 |
2011年 | 13篇 |
2010年 | 12篇 |
2009年 | 13篇 |
2008年 | 9篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2005年 | 3篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1998年 | 2篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 1篇 |
排序方式: 共有195条查询结果,搜索用时 15 毫秒
11.
Polypropylene (PP)/clay nanocomposites are prepared using different grades of PP, compatibilizers, and organically modified clays. The melt intercalation of the PP is carried out in presence of a compatibilizer. The nanocomposites are characterized using various techniques for the structure and properties. X‐ray diffraction results indicate well‐defined structures. Thermogravimetric analysis indicates improved thermal stability of PP/clay nanocomposites. Isothermal crystallization studies carried out using differential scanning calorimeter illustrate enhanced crystallization of PP in all the nanocomposites. Optical microscopic study demonstrates that the nanocomposites can be crystallized at higher temperatures, exhibiting well‐defined birefringent structures. The dynamic mechanical analysis reveals higher storage moduli over a temperature range of ?400C to 1200C for nanocomposites, and the extent of increase in the storage modulus is dependent on the type of compatibilizer used. 相似文献
12.
Most human deaths are caused by heart diseases. Such diseases cannot be efficiently detected for the lack of specialized knowledge and experience. Data science is important in healthcare sector for the role it plays in bulk data processing. Machine learning (ML) also plays a significant part in disease prediction and decision-making in medical care industry. This study reviews and evaluates the ML approaches applied in heart disease detection. The primary goal is to find mathematically effective ML algorithm to predict heart diseases more accurately. Various ML approaches including Logistic Regression, Support Vector Machine (SVM), k-Nearest Neighbor (k-NN), t-Distributed Stochastic Neighbor Embedding (t-SNE), Nave Bayes, and Random Forest were utilized to process heart disease dataset and extract the unknown patterns of heart disease detection. An analysis was conducted on their performance to examine the effecacy and efficiency. The results show that Random Forest out-performed other ML algorithms with an accuracy of 97%. 相似文献
13.
Nitu Bhatnagar Sangeeta Jha Shantanu Bhowmik Govind Gupta J. B. Moon C. G. Kim 《Surface Engineering and Applied Electrochemistry》2012,48(2):117-126
In this work, the effect of low pressure plasma and atmospheric-pressure plasma treatment on surface properties and adhesion characteristics of high performance polymer, Polyether Ether Ketone (PEEK) are investigated in terms of Fourier Transform Infrared Spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Atomic Force Microscopy (AFM). The experimental results show that the PEEK surface treated by atmospheric pressure plasma lead to an increase in the polar component of the surface energy, resulting in improving the adhesion characteristics of the PEEK/Epoxy adhesive system. Also, the roughness of the treated surfaces is largely increased as confirmed by AFM observation. These results can be explained by the fact that the atmospheric pressure plasma treatment of PEEK surface yields several oxygen functionalities on hydrophobic surface, which play an important role in increasing the surface polarity, wettability, and the adhesion characteristics of the PEEK/Epoxy adhesive system. 相似文献
14.
15.
Strategies to encode or label small particles or beads for use in high-throughput screening and bioassay applications focus on either spatially differentiated, on-chip arrays or random distributions of encoded beads. Attempts to encode large numbers of polymeric, metallic or glass beads in random arrays or in fluid suspension have used a variety of entities to provide coded elements (bits)--fluorescent molecules, molecules with specific vibrational signatures, quantum dots, or discrete metallic layers. Here we report a method for optically encoding micrometre-sized nanostructured particles of porous silicon. We generate multilayered porous films in crystalline silicon using a periodic electrochemical etch. This results in photonic crystals with well-resolved and narrow optical reflectivity features, whose wavelengths are determined by the etching parameters. Millions of possible codes can be prepared this way. Micrometre-sized particles are then produced by ultrasonic fracture, mechanical grinding or by lithographic means. A simple antibody-based bioassay using fluorescently tagged proteins demonstrates the encoding strategy in biologically relevant media. 相似文献
16.
S. K. Sasamal R. C. Panigrahy Sangeeta Misra 《International journal of remote sensing》2013,34(17):3853-3858
Asterionella glacialis Castracane, a diatom species of marine phytoplankton, bloomed in the coastal waters of the northwestern Bay of Bengal during 24 March to 4 April 2004. This species dominated by 99% in cell concentration on 26 March 2004. During the bloom period, phytoplankton population density increased by three orders of magnitude, while the chlorophyll a concentration increased by 70 to 80 times relative to the pre‐bloom situation. The blooming was associated with coastal upwelling and influenced water quality. Corresponding to the blooming period, satellite sensor‐derived products of sea surface temperature (SST) and chlorophyll a data were analysed to understand the coverage and dynamics of phytoplankton in the area. 相似文献
17.
S. C. Sabharwal Sangeeta Madhumita Goswami S. K. Kulkarni B. D. Padalia 《Journal of Materials Science: Materials in Electronics》2000,11(4):325-329
Beta barium borate (-BBO) crystals have been grown by the top seeded solution growth technique (TSSG) using Na2O as a flux. The crystals exhibited high transparency and the absence of inclusions and found to have sodium contamination in the range 150 to 230 p.p.m. The effect of this contamination on some crystal properties of interest has been investigated. The presence of impurities causes optical absorption below 550 nm in BBO crystals of both and -phases. X-ray photo emission spectroscopy (XPS) measurements performed on these crystals show that sodium gives rise to a measurable shift in the binding energies of the constituent ions. Further, the results show that Na+ ions enter into the lattice substitutionally and provide charge trapping sites close to the band edge. 相似文献
18.
Self‐Sealing Porous Silicon‐Calcium Silicate Core–Shell Nanoparticles for Targeted siRNA Delivery to the Injured Brain 下载免费PDF全文
19.
Silicon - Ge-source dopingless tunnelling field effect transistor (Ge-source DLTFET) with the optimization of dielectric oxide thickness under the source and the gate contacts is proposed and... 相似文献
20.