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1.
强电场电离放电产生羟基等离子体反应过程的研究 总被引:2,自引:0,他引:2
从强电场等离子体反应室结构、电介质材料及加工工艺等方面出发.研究了在建立强电场并把O2、H2O电离后在分子层次上加工成OH^ 、eaq^-(水合电子)等自由基的等离子体反应过程。用这种方法产生的自由基的浓度、产成量均能满足工程上的需要.达到绿色化学12条原则要求,从源头上解决了环境污染问题。着重研究了羟基治理烟气SO2的绿色资源化的新方法.在无吸收剂、催化剂条件下,仅在0.8s内就能把烟气中SO2、H2O和O2电离后在分子层次上加工成H2SO4。 相似文献
2.
Kowalewski T McCullough RD Matyjaszewski K 《The European physical journal. E, Soft matter》2003,10(1):5-16
The development of new controlled/living radical polymerization processes, such as Atom Transfer Radical Polymerization (ATRP)
and other techniques such as nitroxide mediated polymerization and degenerative transfer processes, including RAFT, opened
the way to the use of radical polymerization for the synthesis of well-defined, complex functional nanostructures. The development
of such nanostructures is primarily dependent on self-assembly of well-defined segmented copolymers. This article describes
the fundamentals of ATRP, relevant to the synthesis of such systems. The self-assembly of block copolymers prepared by ATRP
is illustrated by three examples. In the first, block copolymers of poly(butyl acrylate) with polyacrylonitrile phase separate,
leading to spherical, cylindrical or lamellar morphologies, depending on the block copolymer composition. At a higher temperature,
polyacrylonitrile block converts to nanostructured carbon clusters, whereas poly(butyl acrylate) block serves as a sacrificial
block, aiding the development of designed nanostructures. In the second example, conductive nanoribbons of poly(n-hexylthiophene)
surrounded by a matrix of organic polymers are formed from block copolymers prepared by ATRP. The third example describes
an inorganic-organic hybrid system consisting of hard nanocolloidal silica particles (20 nm) grafted by ATRP with well-defined
polystyrene-poly(benzyl acrylate) block copolymer chains (1000 chains per particle). Silica cores in this system are surrounded
by a rigid polystyrene inner shell and softer polyacrylate outer shell.
Received 9 July 2002 Published online: 11 March 2003 相似文献
3.
随着机器人在各领域的广泛应用和任务种类多样化,单机器人执行任务受到任务规模和复杂程度的限制,使用多个机器人协作完成任务是解决复杂问题的有效方法之一。在复杂机器人控制系统中,不同的任务往往需要不同的机器人去执行,这些机器人一般具有不同的结构和功能,而且工业化的机器人各自遵循私有协议。在操作一个复杂多机器人系统中,控制系统中的通信协议因不同的机器人而异,从而增加了控制过程中的协作难度。设计和制定一个方便的交互协议,便于协作信息在系统中通信,共同完成给定的任务。本文针对不同的机器人私有控制协议,在一致化交互接口的基础上,设计并实现了不同工业机器人之间的交互。通过工程实践,验证了这种一致性交互协议对于异构机器人系统的有效交互,对完成复杂问题作业具有借鉴作用。 相似文献
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I. Kirschner R. Laiho P. Lukács A. C. Bódi M. Dimitrova-Lukács E. Lähderanta G. Zsolt 《Zeitschrift für Physik B Condensed Matter》1995,99(1):501-506
Some main features of the non-linear synthesis process are described by theoretical considerations. Results of typical preparation
methods are compared to each other and to those obtained by the experiments designed specially for the study of the effect
of synthesis on the superconducting properties of Hg−Ba−Ca−Cu−O compounds. As is shown, the controlled Hg-vapour pressure
method, the sealed tube with phase formation procedure, the high-pressure synthesis and the freeze-drying method seem to be
unambiguously reliable to provide high-quality samples. Significant deviations from these fundamental synthesis routes can
lead to significant deviations of superconducting parameters. 相似文献
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7.
G. Padeletti A. Cusmá G.M. Ingo A. Santoni S. Loreti C. Minarini M. Viticoli 《Applied Physics A: Materials Science & Processing》2003,76(5):801-808
In the last few years, intensive research activity has been focused on the development of suitable synthesis methods for high-permittivity
materials, used for the realization of next-generation microdevices able to fulfil the previsions of the Technology Roadmap
of Semiconductors. The use of high-permittivity materials can overcome the difficulties concerning the production of SiO2-based ultra-thin dielectrics, such as the generation of pinholes and the non-uniformity of the film, which may result in
a malfunction in high-density systems. Recently, zirconium titanate thin films were discovered to have very interesting dielectric
properties, which suggests a use for them in microwave integrated systems, such as receivers or DRAMs, since they are monophasic,
have little dissipation and show a good thermal stability and a high value for the dielectric constant, independent of frequency
in the range from kilohertz to a few gigahertz. Real application is possible only in strict connection with the development
of a suitable preparation method which allows production with controlled and reproducible characteristics. In this work, the
synthesis and characterization of ZrxTi1-xO4 (ZT) thin films grown via MO-CVD is described, studying the influence of growth parameters on their structural, chemical
and physical properties.
Received: 17 June 2002 / Accepted: 24 June 2002 / Published online: 4 November 2002
RID="*"
ID="*"Corresponding author. Fax: +39-06/9067-2445, E-mail: Pad@mlib.cnr.it 相似文献
8.
D. Ruiz-Molina N. Ventosa F. Palacio J. Veciana 《Journal of Physics and Chemistry of Solids》2004,65(4):737-744
The new polychlorotriphenylmethyl tetraradical 1 has been obtained and its magnetic properties studied. The large overcrowding present in this dendritic radical has been shown not only to affect its synthesis but its magnetic properties. Even though steric hindrance is an extremely efficient tool to increase the persistence of high-spin species, it may lead to undesired steric congestions that disfavor the desired ferromagnetic coupling between meta connected radical units. 相似文献
9.
Rajashree Patil Priyanka Bhoir Padmini Deshpande Tejas Wattamwar Mahesh Shirude Pratip Chaskar 《Ultrasonics sonochemistry》2013,20(6):1327-1336
Medicinal chemistry has been benefited by combinatorial chemistry and high throughput parallel synthesis. The use of sonochemistry under controlled conditions has been proved beneficial for medicinal chemistry and drug discovery process since it dramatically reduces reaction times, from days or hours to minutes. In addition, sonochemistry synthesis provides higher yields, lower cost, easy workups and greater purity as compared to lower yields, tedious workups, longer reaction times, lesser purity and termination of many by-products in the conventional thermal methods. 相似文献
10.
C. C. Chen H. L. Kao K. C. Chiang Albert Chin 《International Journal of Infrared and Millimeter Waves》2006,27(1):91-103
This paper reports our progress in developing parallel coupled-line filters based on Si-based VLSI backend interconnects for
millimeter-wave applications. The resonant frequency of this coupled-line filter increases with increasing spacing-gap and
with increasing IDM thickness. By using high resistivity substrate, the parallel coupled-line band-pass filter is extremely
effective in reducing substrate loss, and also provides very low insertion loss, even at the millimeter-wave regime. In addition,
the parallel coupled-line filter suitable for advanced system-on-a-chips at the millimeter wave application achieves high
performance characteristics, which show low insertion loss, wide band, and compatibility with standard VLSI process. 相似文献
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Z. Q. Huang M. H. Hong T. B. M. Do Q. Y. Lin 《Applied Physics A: Materials Science & Processing》2008,90(1):159-163
TiB2-based cermets are prepared by combustion synthesis followed by a pressing stage in a granulate medium. Products obtained
by combustion synthesis are characterized by a large remaining porosity (typically 50%). To produce dense cermets, a subsequent
densification step is performed after the combustion process and when the reacted material is still hot. To design the process,
numerical simulations are carried out and compared to experimental results. In addition, physical and electrical properties
of the products related to electrical contact applications are evaluated.
PACS 81.20.Ka; 81.05.Mh; 72.80.Tm 相似文献
13.
In this paper, the collective motion of self-driven robots is studied experimentally and theoretically. In the channel,the flowrate of robots increases with the density linearly, even if the density of the robots tends to 1.0. There is no abrupt drop in the flowrate, similar to the collective motion of ants. We find that the robots will adjust their velocities by a serial of tiny collisions. The speed-adjustment will affect both robots involved in the collision, and will help to maintain a nearly uniform velocity for the robots. As a result, the flowrate drop will disappear. In the motion, the robots neither gather together nor scatter completely. Instead, they form some clusters to move together. These clusters are not stable during the moving process, but their sizes follow a power-law-alike distribution. We propose a theoretical model to simulate this collective motion process, which can reproduce these behaviors well. Analytic results about the flowrate behavior are also consistent with experiments. 相似文献
14.
G.S. Duesberg J. Muster H.J. Byrne S. Roth M. Burghard 《Applied Physics A: Materials Science & Processing》1999,69(3):269-274
Production methods for carbon nanotubes are now well established and allow their synthesis on a scale of grams per day. For
many potential applications of this unique material, its purification still remains a crucial problem. In this article various
purification methods for single- and multi-wall carbon nanotubes are reviewed. These methods are compared in terms of their
capacity, efficiency, and effects on the tubes. In addition, the use of Raman spectroscopy for monitoring the chromatographic
purification of single-wall nanotubes is described.
Received: 17 May 1999 / Accepted: 18 May 1999 / Published online: 29 July 1999 相似文献
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Chang Xu Tao Wu Charles Michael Drain Michael J. Fasolka 《Applied Surface Science》2006,252(7):2529-2534
We outline a method to fabricate gradient combinatorial libraries that explore architectural parameters of surface-grafted block copolymers (BCs). In addition, we demonstrate the utility of such libraries for the rapid, thorough assessment of the response of grafted BCs to solvent exposure. Our fabrication route uses surface-initiated controlled radical polymerization to produce a tethered polymer block with uniform length (in this case, poly(n-butyl methacrylate), PBMA), followed by a graded synthesis that adds a second block that varies in its length over the library (here, poly(2-(N,N′-dimethylamino)ethyl methacrylate), PDMAEMA). Our demonstration study maps the response of PBMA and PDMAEMA blocks to hexane and water, and defines regimes of behavior to this respect. Moreover, our study illuminates a narrow BC composition window that exhibits the strongest possible response to water and hexane treatment. 相似文献
17.
ZHU Yabin ZHOU Yueliang LIU Zhen WANG Shufang CHEN Zhenghao U Huibin YANG Guozhen XlAO Ling Ren Hongtao JIAO Yulei Zheng Minghui 《中国科学G辑(英文版)》2004,47(2):165-172
The irreversibility field (Hirr) of Y-based superconductor is much higher than that of Bi-based superconductor. Y-based superconductor is capable of maintaining stable electrical currents in high magnetic field and electric field, so it is a better suited mate-rial for electric-current applications. Commonly, the Y-based tapes comprise a YBCO thick film deposited on a flexible substrate, typically with an intermediate buffer layer, and an overcoat of noble metal. In this process, the interm… 相似文献
18.
Richard Shurtleff 《General Relativity and Gravitation》1995,27(5):495-509
Two pairs of parallel geodesic intervals can be generated from two such intervals with a common endpoint by suitable application of parallel transfer. When the connection coefficients are symmetric, a parallelogram-like figure with a closed perimeter can be constructed with the two pairs of sides. When the connection coefficients are asymmetric, combining the two pairs of parallel intervals yields a figure with a coordinate gap. To avoid an open perimeter, a fiber that contains many coordinate-like labels is constructed for each point. Then the gap can occur in the fiber of a single point. Thus a closed figure is obtained even when the connection is asymmetric. A process to obtain the coordinate-like quantities in the fiber of one point with respect to a nearby point is described. A discussion of transformations of the coordinate-like quantities follows and the fundamental curvature-like quantity is obtained. 相似文献
19.
Nickel nanowires, with diameter 250 nm and a length of several microns, were prepared by the polyol process (chemical reduction) while an external magnetic field of 1.4 T has been applied during preparation. This combination has allowed the elaboration of Ni nanowires with a yield of over 90%. X-ray diffraction (XRD) showed that these nanowires crystallize with the face-centered-cubic structure. Magnetic static measurements showed the effect on the nanoparticles’ morphology of the external magnetic field applied during the synthesis. They also allowed studying the effect of the external magnetic field on the magnetic properties of nanowires as a function of their orientation. When nanowires are aligned parallel with magnetic field, the hysteresis loop obtained is very open with a coercivity field (Hc) value of 385 Oe and a high remanence to saturation ratio Mr/Ms of 0.85. 相似文献
20.
The parallel solution synthesis of three classes ofheterocycles is described. Arrays of pyridinethiones,pyridinones and thienopyridines were prepared usingone-step chemistry starting from readily accessiblebuilding blocks. The latter class of compounds wasaccessed by utilising a library-from-library approach. 相似文献