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91.
Yamakawa S. Sugihara K. Furukawa T. Nishioka Y. Nakahata T. Abe Y. Maruno S. Tokuda Y. 《Electron Device Letters, IEEE》1999,20(7):366-368
Deep submicron MOSFETs with elevated source/drain (S/D) structures, where S/D extension regions were partially elevated besides deep S/D regions, were fabricated by use of Si selective epitaxial growth technique. As fairly compared with a well-developed conventional MOSFET, we clarify an advantage of the elevated S/D structures, i.e., improvement upon driving performance with keeping excellent short-channel characteristics, which is enhanced for decrease in gate sidewall spacer width. The experimental results are explained in terms of the reduction in S/D parasitic resistance by addition of the Si epitaxial layer where the impurity profile is suitable 相似文献
92.
Summary
Organocobalt poly(arylene-vinylene)s composed of 1,2- or 1,3- linkage at their cyclobutadiene moieties (3 and 4, respectively) were prepared by the Heck reaction of p-divinylbenzene with (cyclobutadiene)cobalt-containing monomers having two aryl bromide moieties (1 and 2, respectively). The number average molecular weights (M
n) of the obtained organocobalt poly(arylene-vinylene)s (3 and 4) were 4,100 and 4,000, respectively (GPC, on the basis of polystyrene). UV-vis spectra of 3 and 4 exhibited main π-π* absorption peaks at 362 and 397 nm, respectively, which were ca. 60 nm bathochromically shifted from those of the corresponding
monomeric units. Both polymers were found to show thermotropic liquid crystallinity in the range of room temperature to ca.
80 °C by employing differential scanning calorimetry (DSC) and the optical measurement using crossed polarizers.
Received: 2 July 1999/Accepted: 29 July 1999 相似文献
93.
Attenuation loss change in submarine coaxial cables during 4 years of storage has been measured. Attenuation loss is shown to increase for one year after manufacturing. Then, loss is also shown to increase during summer (May to October) and to stay constant or to decrease during winter (November to April of the next year). This work concentrates on the causes and an estimation method of loss aging. The first part of the paper covers experimental results on the cable aging phenomenon. The second part discusses various factors affecting loss aging, and shows that fretting corrosion on the outer conductor tape will be a main factor. The third part describes an estimation method for and countermeasures to avoid loss aging during cable storage. 相似文献
94.
The authors have demonstrated photochemical deposition of aluminum oxides from Trimethylaluminum (TMA) and N2O by using a pulsed ArF excimer laser (193 nm). Both TMA and N2O are efficiently photodissociated by the 193 nm light. The films are grown on Si and InP wafers contained in a low pressure
flowing cell with a heated substrate. The incident laser beam is focused and parallel to the substrate surface. Typical deposition
rates are 80–150 A/min. Stripes of aluminum oxide 30 mm wide are uniformly grown on 7.5 cm Si-wafers. The film composition
and purity have been investigated using Auger and Infra-red spectroscopy analysis. Surprising results are the relatively low
concentration of carbon. Refractive index and thickness have been determined by an ellipsometer. Typical values for the films
are 1.54–1.62. Metal-oxide-semiconductor capacitors have been fabricated and characterized. The C-V curves for n-InP/aluminum
oxide have clockwise hysteresis, and minimum loop width is less than 0.5 V. The surface state densities are 1 × 1011 cm-2 eV−1 at the mid band gap. 相似文献
95.
Bong Mo Park Kenji Kitamura Yasunori Furukawa Yangyang Ji 《Journal of the American Ceramic Society》1997,80(10):2689-2692
The relationships between cracking and mechanical twinning, and between ferroelectric polarization and mechanical twinning, in stoichiometric LiNbO3 were investigated in the present study. Three sets of mechanical twins crossed one another, and the crossed points of those twins provided preferred sites for the nucleation of cracks. Mechanical twins of LiNbO3 revealed a head-to-tail arrangement of ferroelectric polarization, and complicated polarization states were observed at the crossed points. Some possible mechanisms of crack nucleation and propagation are proposed in this paper. 相似文献
96.
Yamori A. Yanagisawa M. Sato K. Kawashima N. Furukawa T. Teii S. 《IEEE transactions on magnetics》1991,27(1):126-129
A railgun for the study of the interaction of meteorites with planetary surfaces and the interaction of space debris was developed. The authors have attained a velocity constantly higher than 5 km/s, with a maximum of 6 km/s. The importance of plasma confinement behind the projectile to prevent a leakage is shown to realize a high velocity. An effective acceleration using an aluminum rail is also shown 相似文献
97.
Tomohito Hamazaki Shigeki Sawazaki Tetsuro Nagasawa Yoko Nagao Yuko Kanagawa Kazunaga Yazawa 《Lipids》1999,34(1):S33-S37
The purpose of the present research was to clarify the effect of docosahexaenoic acid (DHA) intake on behavior and plasma catecholamines (CA). In Study 1, 42 students took either DHA-rich oil capsules containing 1.5–1.8 g DHA/d or control oil capsules containing 97% soybean oil plus 3% of another fish oil for 3 mon in a double-blind fashion. They took a psychological test (PF Study) at the start and end of the study. This study started at the end of summer vacation and ended just before the final exams. In the control group, external aggression (aggression against others) in PF Study was significantly increased at the end of the study as compared with that measured at the start (+8.9%), whereas it was not significantly changed in the DHA group (?1.0%). In a similar double-blind study (Study 2), we measured external aggression under nonstressful conditions. External aggression slightly decreased in the control group, whereas there were no significant changes in the DHA group. In Study 3 with 14 students, plasma CA were measured at the start and end of capsule administration period of 2 mon. Subjects were under continuous stress of the final exams that lasted throughout the whole study period. The ratio of plasma epinephrine to norepinephrine concentrations was significantly increased in the DHA group (78%), whereas it stayed at the same level in the control group. In Study 4, mice were fed either DHA-deficient diet or -sufficient diet for 4 wk, and their rearing frequency (an anxiety index) was measured. In the DHA-sufficient group, the rearing frequency was significantly less than in the other group. These effects of DHA intake may be applied to people in an attempt to ameliorate stress-related diseases. 相似文献
98.
A historical and technical overview of a paradigm for automating research procedures on the area of constitutive identification of composite materials is presented. Computationally controlled robotic, multiple degree-of-freedom mechatronic systems are used to accelerate the rate of performing data-collecting experiments along loading paths defined in multidimensional loading spaces. The collected data are utilized for the inexpensive data-driven determination of bulk material non-linear constitutive behavior models as a consequence of generalized loading through parameter identification/estimation methodologies based on the inverse approach. The concept of the dissipated energy density is utilized as the representative encapsulation of the non-linear part of the constitutive response that is responsible for the irreversible character of the overall behavior. Demonstrations of this paradigm are given for the cases of polymer matrix composite materials systems. Finally, this computational and mechatronic infrastructure is used to create conceptual, analytical and computational models for describing and predicting material and structural performance. 相似文献
99.
Yuko Hamabe Ryoko Matsuura Akinori Jyo Masao Tamada Akio Katakai 《Reactive and Functional Polymers》2009,69(1):1-8
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin. 相似文献