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121.
Murali Babu Muthukrishnan 《电子元器件资讯》2010,(11)
现在,人人都能使用互联网,它具有采集新闻和内容共享到实时通信多种多样的用途.这些活动主要通过个人计算机和智能手机实现,而在家里联网电视已开始担当这个角色. 相似文献
122.
To gain insight into the synchronization, simultaneity, and switching behavior of the individual switch, two TIA-525 Optical/Electrical
converters have been recently introduced to DPF experiments at Lawrenceville Plasma Physics (LPP). These electronic devices,
attached to two spark gap switches through optical fibers, detect light sampled from the switch firing and convert it to amplified
voltage signals. We observed that in terms of simultaneity and synchronization, the firing behavior and quality of the pair
of switches monitored are not the same. Some switches, among the twelve that are being used, fired at the trigger voltage
within few tens of ns while the others fired much later (after ~1–2 μs) and are triggered at or after the pinch voltage rise.
The results from the present work show evidence of pinch voltage triggering the switches. Since the pinch voltage is over
three times the voltage of the capacitors, this voltage triggers those capacitors that do not fire during the regular high
voltage trigger pulse. This, we suggest, could affect the efficiency of the device as it simply drains the reserved energy
in the system. We present results of an empirical study of spark gap switch firing as well as the total current that is followed
using the Rogowski coil. 相似文献
123.
Preparation of activated graphene and effect of activation parameters on electrochemical capacitance
Shanthi Murali Jeffrey R. Potts Scott Stoller Joono Park Meryl D. Stoller Li Li Zhang Yanwu Zhu Rodney S. Ruoff 《Carbon》2012,50(10):3482-3485
Activation parameters such as temperature and the amount of potassium hydroxide (KOH) were varied during the synthesis of activated microwave-exfoliated graphite oxide (a-MEGO) and the effects of these parameters on the specific surface area of a-MEGO and electrochemical capacitance of a-MEGO electrodes were investigated. At 800 °C and a KOH/MEGO mass ratio of 6.5, a maximum specific surface area of 3100 m2/g was obtained and a high specific capacitance of 172 F/g (at 1 A/g constant current and 3.5 V maximal voltage) was measured in a two-electrode cell with a-MEGO electrodes in an organic electrolyte. 相似文献
124.
Asphalt exhibits Newtonian, non-Newtonian and viscoelastic behavior as the temperature is varied. This investigation reports the temperature at which asphalt exhibits non-Newtonian to Newtonian transition. Air blown, blended asphalt and petroleum pitch were tested at different aging conditions. The temperature at which the material exhibited shear rate independent viscosity was taken as the transition temperature. The transition temperature varied with processing method and aging conditions. It was seen that blended asphalt exhibited greater increase in apparent viscosity during aging when compared to air blown asphalt, whereas air blown asphalt showed greater shift in transition temperature for the same aging conditions. 相似文献
125.
In this paper, we propose a novel test of independence based on the concept of correntropy. We explore correntropy from a statistical perspective and discuss its properties in the context of testing independence. We introduce the novel concept of parametric correntropy and design a test of independence based on it. We further discuss how the proposed test relaxes the assumption of Gaussianity. Finally, we discuss some computational issues related to the proposed method and compare it with state-of-the-art techniques. 相似文献
126.
V. S. Vidhya J. Vatsala Rani A. Ratheesh Kumar R. Thangamuthu K. R. Murali M. Jayachandran 《Journal of Materials Science: Materials in Electronics》2011,22(9):1460-1465
ZnO thin films were potentiostatically electrodeposited on transparent tin oxide conducting glass substrates at ?1.0 V (vs. Ag/AgCl) in the presence of anionic surfactant, sodium dodecyl sulphate (SDS) and hydrophobic ionic liquid, 1-butyl-3-methylimidazolium methylsulfate [bmim][CH3SO4]. X-ray diffraction (XRD) investigation confirm the formation of nanocrystalline and stoichiometric ZnO thin films. Scanning electron microscopy (SEM) results reveal that the grain size of the deposited ZnO film is reduced from 85 to 28 nm when small amount of ionic liquid is added to the deposition bath. Photoluminescence study at room temperature shows a clear absorption edge in the ultra violet (UV) region confirming the high quality, nanocrystalline and stoichiometric nature of the deposited ZnO films. 相似文献
127.
M LeBeau W Andollo WL Hearn R Baselt E Cone B Finkle D Fraser A Jenkins J Mayer A Negrusz A Poklis HC Walls L Raymon M Robertson J Saady 《Canadian Metallurgical Quarterly》1999,44(1):227-230
The recent increase in reports of drug-facilitated sexual assaults has caused alarm in the general public and prompted forensic toxicologists from across North America to address the toxicological issues surrounding this matter. The authors have developed recommendations and guidelines to inform law enforcement, medical, and scientific personnel of the requirements for performing successful toxicological examinations in cases of drug-facilitated rape. 相似文献
128.
129.
130.
Purification and crystallization of complexes modeling the active state of the fragile histidine triad protein 总被引:1,自引:0,他引:1
Brenner C; Pace HC; Garrison PN; Robinson AK; Rosler A; Liu XH; Blackburn GM; Croce CM; Huebner K; Barnes LD 《Protein engineering, design & selection : PEDS》1997,10(12):1461-1463
Fragile histidine triad protein (Fhit) is a diadenosine triphosphate
(ApppA) hydrolase encoded at the human chromosome 3 fragile site which is
frequently disrupted in tumors. Reintroduction of FHIT coding sequences to
cancer cell lines with FHIT deletions suppressed the ability of these cell
lines to form tumors in nude mice even when the reintroduced FHIT gene had
been mutated to allow ApppA binding but not hydrolysis. Because this
suggested that the tumor suppressor activity of Fhit protein depends on
substrate-dependent signaling rather than ApppA catabolism, we prepared two
crystalline forms of Fhit protein that are expected to model its
biologically active, substrate-bound state. Wild-type and the His96Asn
forms of Fhit were overexpressed in Escherichia coli, purified to
homogeneity and crystallized in the presence and absence of ApppA and an
ApppA analog. Single crystals obtained by vapor diffusion against ammonium
sulfate diffracted X-rays to beyond 2.75 A resolution. High quality native
synchrotron X-ray data were collected for an orthorhombic and a hexagonal
crystal form.
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