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61.
Jrg Kressler Bernd Rudolf Ken Shimomai Toshiaki Ougizawa Takashi Inoue 《Macromolecular rapid communications》1995,16(8):631-636
Pressure, volume, temperature (PVT) measurements reveal that during the intramolecular cyclization reaction of poly(acrylonitrile) (PAN) and poly(styrene-co-acrylonitrile) (SAN) the volume decreases. This volume contraction becomes smaller with increasing styrene content in the random copolymers and should be related to the simultaneous decrease of longer acrylonitrile homo-sequences. The onset temperature of the cyclization reaction is raised with higher styrene contents in the random copolymers. Thus, it can be excluded that the cyclization reaction has a major influence on the discoloration process of SAN samples having relatively small acrylonitrile contents (less than 50 mol-%) during thermal annealing below 300°C. 相似文献
62.
LG. Philips LCD (LPL) announced at Sept. 13th 2006, it has developed the industry's fastest TFT-LCD panel for mobile phones, which will permit next-generation handsets to display TV and video content with less motion blur. 相似文献
63.
Ken Manchen 《今日电子》2006,(1):67-67
欧盟的《禁止使用有害物质指令》(RoHS)和《报废电子电气设备指令》(WEEE)有力地推动了将已颁布的环保法律付诸实施.其影响已经扩展到欧盟以外的地区。下面是其他国家和地区的有关概况。 相似文献
64.
A simple Cu-DNAzyme system is used for signal transduction of a CuO nanoparticle-labeled immunoassay, which makes the immunoassay fast, simple, cost-effective, and sensitive, thus promising for biomedical applications and point-of-care testing. 相似文献
65.
Dynamics of ice nucleation on water repellent surfaces 总被引:3,自引:0,他引:3
Alizadeh A Yamada M Li R Shang W Otta S Zhong S Ge L Dhinojwala A Conway KR Bahadur V Vinciquerra AJ Stephens B Blohm ML 《Langmuir : the ACS journal of surfaces and colloids》2012,28(6):3180-3186
Prevention of ice accretion and adhesion on surfaces is relevant to many applications, leading to improved operation safety, increased energy efficiency, and cost reduction. Development of passive nonicing coatings is highly desirable, since current antiicing strategies are energy and cost intensive. Superhydrophobicity has been proposed as a lead passive nonicing strategy, yet the exact mechanism of delayed icing on these surfaces is not clearly understood. In this work, we present an in-depth analysis of ice formation dynamics upon water droplet impact on surfaces with different wettabilities. We experimentally demonstrate that ice nucleation under low-humidity conditions can be delayed through control of surface chemistry and texture. Combining infrared (IR) thermometry and high-speed photography, we observe that the reduction of water-surface contact area on superhydrophobic surfaces plays a dual role in delaying nucleation: first by reducing heat transfer and second by reducing the probability of heterogeneous nucleation at the water-substrate interface. This work also includes an analysis (based on classical nucleation theory) to estimate various homogeneous and heterogeneous nucleation rates in icing situations. The key finding is that ice nucleation delay on superhydrophobic surfaces is more prominent at moderate degrees of supercooling, while closer to the homogeneous nucleation temperature, bulk and air-water interface nucleation effects become equally important. The study presented here offers a comprehensive perspective on the efficacy of textured surfaces for nonicing applications. 相似文献
66.
Simon R. Drake Brian F. G. Johnson Jack Lewis 《Journal of organometallic chemistry》1988,340(3):C31-C36
The heteronuclear clusters [Os10C(CO)24(MPR3nm− (n = 1, m = 1; 2: M = Au; 3: M = Ag; 4: M = Cu; 5 n = 2, m = 0, M = Ag) have been prepared. These clusters undergo molecular rearrangements in solution, and two isomeric forms of 2, 3, 4, 5 and 6 have been identified. This interconversion is thought to involve a cap [lrarr2] edge bridge [lrarr2] cap pathway. 相似文献
67.
Chen Ken Wang Ping Wang Lunyao 《电子科学学刊(英文版)》2007,24(6):792-797
In this paper the design and implementation of Multi-Dimensional (MD) filter, particularly 3-Dimensional (3D) filter, are presented. Digital (discrete domain) filters applied to image and video signal processing using the novel 3D multirate algorithms for efficient implementation of moving object extraction are engineered with an example. The multirate (decimation and/or interpolation) signal processing algorithms can achieve significant savings in computation and memory usage. The proposed algorithm uses the mapping relations of z-transfer functions between non-multirate and multirate mathematical expressions in terms of time-varying coefficient instead of traditional polyphase de- composition counterparts. The mapping properties can be readily used to efficiently analyze and synthesize MD multirate filters. 相似文献
68.
Satoshi Iikubo Shin-ichi Shamoto Ken Takeuchi Katsuaki Kodama 《Journal of Physics and Chemistry of Solids》2010,71(11):1603-1608
The local crystal structure of dried and deuterated nano-manganese-oxide powder samples was studied via atomic pair distribution function analysis of X-ray and neutron powder diffraction data. The protonated sample shows ultrahigh efficiency as a gold adsorbent even from ppt-level aqueous solutions such as seawater. We show that the nano-manganese-oxide particles have an R-MnO2-type local crystal structure. The possible role of the protons on the surface of the nano-particles is discussed. 相似文献
69.
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