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   59篇
  免费   1篇
化学   37篇
力学   4篇
数学   7篇
物理学   12篇
  2023年   1篇
  2022年   2篇
  2021年   2篇
  2020年   2篇
  2019年   3篇
  2018年   3篇
  2017年   6篇
  2016年   4篇
  2015年   4篇
  2014年   3篇
  2013年   6篇
  2012年   3篇
  2011年   3篇
  2010年   1篇
  2009年   3篇
  2008年   2篇
  2007年   2篇
  2006年   1篇
  2005年   1篇
  2004年   3篇
  2003年   3篇
  1985年   1篇
  1978年   1篇
排序方式: 共有60条查询结果,搜索用时 31 毫秒
31.
32.
This study describes the synthesis of molecularly imprinted polymers (MIPs) using bovine albumin as a template, 2-VP as a functional monomer, EGDMA as a cross-linker and AIBN as an initiator by radical polymerization. Non-imprinted polymers (NIPs) were prepared and treated with the same method, but in the absence of bovine albumin. The synthesized MIPs and NIPs were characterized on the basis of FTIR, TGA and DTA. An adsorption process (solid phase extraction, SPE) for the removal of bovine albumin using the fabricated MIPs and NIPs was evaluated under various conditions. Effective parameters on bovine albumin retention for example, pH, flow rate, nature of the eluent, the ionic strength, selectivity coefficient, and retention capacity were studied. Competition test implicates that the MIP adsorbents have the strongest specific retention and enrichment for bovine albumin respect to NIPs. The maximum adsorption of bovine albumin by the fabricated MIPs was 24 mg/g. The calibration curves were linear in the range of 20–200 mg/L of bovine albumin. The limit of detection (LOD), the calibration sensitivity, the relative standard deviation (RSD) and preconcentration factor under optimal experimental conditions were 2.44 and 25, respectively. The extraction of bovine albumin from blood serum, urine, whey and milk samples had a selectivity and enrichment property. In the actual experiment for real samples, recovery of ~ 80% was achieved.  相似文献   
33.
GenCos need the day-ahead unit commitment solutions in deregulated markets which are feasible, applicable in practice and consistent with the long-term planning decisions. However, such decisions are both vast in scope and different in nature so that applying a monolithic approach is subject to some difficulties and shortcomings. This paper aims to coordinate the long-term decision process with the day-ahead market scheduling through developing a profit-based fuzzy hierarchical bi-level approach. First, an annual planning model with monthly periods at power plant-generation technology level; then based upon a monthly scheduling with daily periods at generating unit level. An interactive solution method involving the soft coordination and feedback mechanisms using rolling horizon strategy is also presented. In the developed models, we try to address critical aspects of power system optimization. This approach is implemented for a real case and analytical results are reported.  相似文献   
34.
This article presents a mixed-integer model to optimize the location of facilities and the underlying transportation network at the same time to minimize the total transportation and operating costs. In this problem, it is assumed that for connecting two nodes, there are several types of links in which their capacity, transportation and construction costs are different. The developed model has various applications in telecommunication, emergency, regional planning, pipeline network, energy management, distribution, to just name a few. To solve the model effectively, this paper also proposes a fix-and-optimize heuristic based on the evolutionary fire-fly algorithm. Finally, to validate the model and evaluate the algorithm’s performance, a series of test instances with up to 100 nodes and 600 candidate links with three different levels of quality are reported.  相似文献   
35.
Palladium nanoparticles were deposited and reduced by gelatin as a safe edible, naturally occurring and cheap support. No extra reducing agents were used for the generation of Pd(0) nanoparticles from the Pd(II) salt. The nanoparticles of Pd supported on gelatin were characterized by SEM, TEM and AFM images, UV-Vis and XRD spectra and the amount of palladium entrapped in the gelatin was measured by ICP and atomic absorption analysis. The nanoparticles showed high catalytic activity for the Sonogashira-Hagihara coupling reaction of various aryl iodides, bromides and chlorides as well as heteroaryl halides and also β-bromo styrene with phenylacetylene under copper-, ligand- and amine-free conditions. The reactions were carried out at 100 °C in molten tetrabutylammonium bromide (TBAB) or polyethylene glycol (PEG400) in the presence of potassium acetate as a base in argon atmosphere. Dimerization of phenylacetylene applying similar conditions in air is also described.  相似文献   
36.
The design of high speed, compact and low power fat tree encoder circuits using static CMOS gates is presented. In this paper, we propose a modified 3 bit fat tree encoder (FTE) that can operate in high frequency without a sophisticated circuit structure. In addition, the technique of hardware sharing is adopted in this design to reduce the number of transistors. The study uses complementary metal oxide semiconductor (CMOS) 45 nm-technology. The proposed static design has improved delay and power compared to a conventional ROM encoder circuit implementation. The simulation result indicates that it functions successfully and works at 200-MHz speed. The average power consumption of the circuit under room temperature is 20.7 nW. The total core area is 0.011 mm2. As expected, the proposed design can be easily integrated in various kind of digital application.  相似文献   
37.
38.
Journal of the Iranian Chemical Society - The preparation and characterization of cobalt aluminate (CoAl2O4) magnetic nanoparticles and its application as a catalyst for the synthesis of a novel...  相似文献   
39.
Organically modified montmorillonite (OMMT) was used as synergist to enhance the flame-retardant and mechanical properties of poly(butylene succinate)/intumescent flame retardant (PBS/IFR) composites. The flame-retardant, thermal degradation and combustion properties of PBS and its flame-retardant composites were characterized by limiting oxygen index (LOI) test, vertical burning (UL-94) test, thermogravimetric analysis, cone calorimeter and scanning electron microscopy, respectively. The results indicate that PBS/IFR composites exhibit excellent flame retardance when OMMT is at an appropriate content. PBS/IFR composite with 20 wt% IFR and 1.5 wt% OMMT has an LOI of 40.1% and can pass the UL-94 V0 rating. The synergistic effect between OMMT and IFR on the flame-retardant properties of PBS depends on the content of OMMT, and excessive OMMT diminish this synergistic effect. The possible flame-retardant mechanism of OMMT on PBS/IFR composite is proposed. The results of mechanical test also indicate that OMMT can effectively increase the notched impact strength of PBS/IFR composites.  相似文献   
40.
Molecular Diversity - The preparation of double salt of aluminum sulfate–sulfuric acid (Al4(SO4)6·(H2SO4)·24H2O) by the reaction of aluminum sulfate and sulfuric acid in water is...  相似文献   
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