首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   113篇
  免费   1篇
电工技术   3篇
化学工业   21篇
金属工艺   1篇
机械仪表   3篇
能源动力   9篇
轻工业   10篇
无线电   13篇
一般工业技术   35篇
冶金工业   3篇
原子能技术   1篇
自动化技术   15篇
  2024年   4篇
  2023年   1篇
  2022年   5篇
  2021年   8篇
  2020年   3篇
  2019年   8篇
  2018年   9篇
  2017年   4篇
  2016年   1篇
  2015年   2篇
  2014年   5篇
  2013年   3篇
  2012年   5篇
  2011年   10篇
  2009年   7篇
  2008年   5篇
  2007年   5篇
  2006年   6篇
  2005年   5篇
  2004年   1篇
  2003年   4篇
  2002年   3篇
  2001年   1篇
  1998年   3篇
  1997年   1篇
  1995年   3篇
  1994年   1篇
  1993年   1篇
排序方式: 共有114条查询结果,搜索用时 0 毫秒
71.
Vision-based human motion tracking has gained significant interest in recent years, as the need for more intuitive human–computer interaction paradigms are sought after. Immersive environments, such as large-scale displays and virtual reality systems are particularly suitable for such interaction mechanisms, as they provide a controlled basis for experimentation and evaluation. However, despite the growing interest, human-motion tracking within immersive environments is still in its infancy. The lack of visible light and the presence of multiple people within such environments pose several challenges to the problem. In this research a robust framework for real-time, multi-camera human-motion tracking within an immersive environment is presented. The static nature of the environment is exploited to utilise a novel 2-cohort camera layout. This layout proves to be highly useful for tracking, providing several benefits over existing techniques, which treat all cameras as the same.  相似文献   
72.
We have developed a device that uses microfluidic valves and pumps to meter reagents for subsequent mixing with application to refolding of the protein β-galactosidase. The microfluidic approach offers the potential advantages of automation, cost-effectiveness, compatibility with optical detection, and reduction in sample volumes as opposed to conventional techniques of hand-pipetting or using robotic systems. The device is a multi-layered poly(dimethylsiloxane) on glass device with automated controls for reagent aliquoting and mixing. Refolding experiments have been performed off-chip using existing protocols on the protein β-galactosidase and the refolding yield has been quantified on-chip using fluorescein di-β-d-galactopyranoside, a caged-fluorescent molecule. This work provides the potential to reduce the cost of drug discovery and realization of protein pharmaceuticals.  相似文献   
73.
This paper examines the application of higher harmonic Non-Linear Electrochemical Impedance Spectroscopy (NLEIS) to characterization of colloidal suspensions of clinically relevant microparticle biomarkers derived from monocytes (white blood cells). This study expands on previous linear EIS investigations of microparticle biomarkers’ suspensions and NLEIS studies of non-aqueous colloidal systems. Numerical minimization analysis allowed to develop a more accurate equivalent circuit model for the low frequency region (<1 kHz) and provided qualitative insight into the kinetic and physiological parameters of the system. The developed NLEIS characterization method permitted to resolve several remaining ambiguities in interpretation of low-frequency linear impedance experimental results for microparticles’ suspensions. These results support continued development of the NLEIS method validation and instrumentation for microparticle biomarkers’ analysis, further expanding its clinical diagnostic capabilities.  相似文献   
74.
Tissue engineering/regeneration is based on the hypothesis that healthy stem/progenitor cells either recruited or delivered to an injured site, can eventually regenerate lost or damaged tissue. Most of the researchers working in tissue engineering and regenerative technology attempt to create tissue replacements by culturing cells onto synthetic porous three-dimensional polymeric scaffolds, which is currently regarded as an ideal approach to enhance functional tissue regeneration by creating and maintaining channels that facilitate progenitor cell migration, proliferation and differentiation. The requirements that must be satisfied by such scaffolds include providing a space with the proper size, shape and porosity for tissue development and permitting cells from the surrounding tissue to migrate into the matrix. Recently, chitin scaffolds have been widely used in tissue engineering due to their non-toxic, biodegradable and biocompatible nature. The advantage of chitin as a tissue engineering biomaterial lies in that it can be easily processed into gel and scaffold forms for a variety of biomedical applications. Moreover, chitin has been shown to enhance some biological activities such as immunological, antibacterial, drug delivery and have been shown to promote better healing at a faster rate and exhibit greater compatibility with humans. This review provides an overview of the current status of tissue engineering/regenerative medicine research using chitin scaffolds for bone, cartilage and wound healing applications. We also outline the key challenges in this field and the most likely directions for future development and we hope that this review will be helpful to the researchers working in the field of tissue engineering and regenerative medicine.  相似文献   
75.
We present a microfluidic biosensor that integrates membrane-based preconcentration with fluorescence detection. The concentration membrane was fabricated in polyacrylamide by an in situ photopolymerization technique at the junction of glass microchannels. Liposomes entrapping sulforhodamine B dye molecules were used for signal amplification. The biotin–streptavidin binding system was a model system for evaluating device performance. Biotinylated liposomes were preconcentrated at the membrane by applying an electric field across the membrane. The electric field causes the liposomes to migrate toward the membrane where they are concentrated by a sieving effect. Two orders of magnitude concentration was achieved after applying the electric field for only 2 min. The concentrated bolus was then eluted toward the detection unit, where the biotinylated liposomes were captured by immobilized streptavidin. The integrated system with the preconcentration module shows a 14-fold improvement in signal as opposed to a system that does not include preconcentration.  相似文献   
76.
In this study, a series of blended yarns consisting of 80:20 bamboo/cotton, 67:33 bamboo/cotton, 50:50 bamboo/cotton, 33:67 bamboo/cotton, 20:80 bamboo/cotton, 80:20 bamboo/polyester, 67:33 bamboo/polyester, 50:50 bamboo/polyester, 33:67 bamboo/polyester, and 20:80 bamboo/polyester were produced from blends consisting of bamboo/cotton and bamboo/polyester. Besides these, 100% bamboo, 100% cotton, and 100% polyester were also produced. All the yarns were produced with two levels of twist per meter (TPM) 76 and 90. It can be found that the yarn unevenness characteristic was affected by the blended ratio of cotton, polyester, and regenerated bamboo fiber. The drop in tenacity of blended yarns in comparison to the constituents is generally lower which is attributed to the elongation at break of the yarns. The variability in tenacity in respect of 100% polyester yarn is quite high in comparison with other yarns. The yarn elongation at break of bamboo/cotton-blended yarns is found to be lower than those of bamboo/polyester-blended yarns. The variability in the work of rupture is found to be lower for bamboo/cotton-blended yarns. Yarn friction values of the yarns noticed that polyester exhibits the highest value at the TPM of 76. The yarn torque values from which it is noticed that 100% polyester yarns spun with the TPM of 76 have a higher torque in both the wet and dry states. The quality characters of yarn depend upon the ratio of bamboo, cotton, and polyester in the blend ratio.  相似文献   
77.
    
The bulk nucleation and basal growth of semiconducting nanowires from molten Ga pools has been demonstrated earlier using oxygen/hydrogen plasma over molten Ga pools. Herein, we extend the above concept for bulk synthesis of oxide and sulfide nanowires of low-melting metal melts such as Sn and In. Specifically, nanowires of β-Ga2O3, β-In2O3, SnO2, α-Ga2S3, and β-In2S3 were synthesized using direct reactions between respective molten metal pools and the gases such as oxygen/hydrogen mixture for oxides and H2S for sulfides. In the case of β-Ga2O3 and SnO2, a change in the morphology from nanowires to nanobelts was observed with an increase in the synthesis temperature. No such behavior was observed in the case of β-In2O3. Furthermore, we present evidence for α-Ga2S3 nanowires, which to our knowledge is being reported for the first time in the literature. Our studies with the sulfide nanowires suggest that H2S reacts directly at the molten metal surface to form gallium sulfide. Finally, we discuss the role of chamber pressure and hydrogen on the size distribution of nanostructured β-Ga2O3 and SnO2.  相似文献   
78.
    
The rising amount of greenhouse gases has been contributing to global warming and, subsequently, climate change. Industries such as refineries and power plants emit a significant amount of CO2 into the atmosphere. It is imperative to curb anthropogenic CO2 emissions, and hence, in this effort, we explore the utilization of a refinery emission stream to produce value-added chemicals. The chosen emission stream for the said purpose is a typical flue gas stream from refineries. Following the capture step, this CO2 stream has been leveraged for subsequent valorization processes. Two strategies have been proposed in this paper to valorize the captured carbon dioxide. The first strategy employs the tri-reforming process with a refinery-specific fuel gas stream as the co-reactant. The resulting syngas from tri-reforming has been converted to chemicals such as methanol (MET) and ethanol. Furthermore, to improve the amount of CO2 valorized, another approach with green hydrogen has been considered. The second strategy aims at direct hydrogenation of the captured CO2 stream to produce MET and ethanol. The proposed strategies analyze the feasibility of valorizing captured CO2 from flue gas to MET and ethanol in terms of gross margin per feed and percentage of CO2 valorization. The performance assessment and analysis of the proposed processes have been carried out using simulations in Aspen Plus® that exhibited up to 74% valorization of CO2 into valuable chemicals.  相似文献   
79.
    
A great promise for tissue engineering is represented by scaffolds that host stem cells during proliferation and differentiation and simultaneously replace damaged tissue while maintaining the main vital functions. In this paper, a novel process was adopted to develop composite scaffolds with a core-shell structure for bone tissue regeneration, in which the core has the main function of temporary mechanical support, and the shell enhances biocompatibility and provides bioactive properties. An interconnected porous core was safely obtained, avoiding solvents or other chemical issues, by blending poly(lactic acid), poly(ε-caprolactone) and leachable superabsorbent polymer particles. After particle leaching in water, the core was grafted with a gelatin/chitosan hydrogel shell to create a cell-friendly bioactive environment within its pores. The physicochemical, morphological, and mechanical characterization of the hybrid structure and of its component materials was carried out by means of infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and mechanical testing under different loading conditions. These hybrid polymer devices were found to closely mimic both the morphology and the stiffness of bones. In addition, in vitro studies showed that the core-shell scaffolds are efficiently seeded by human mesenchymal stromal cells, which remain viable, proliferate, and are capable of differentiating towards the osteogenic phenotype if adequately stimulated.  相似文献   
80.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号