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101.
Norinaga Urahama Genzo Iguchi Mitsue Shimizu Kazuhiro Fujihira Shunzo Kobayashi Hisamitsu Baba 《Nicotine & tobacco research》2008,10(8):1391-1395
All forms of tobacco cause cardiovascular disease, and tobacco-related disease is a leading cause of death worldwide. Smoking oxidizes low-density lipoprotein (LDL) particles, and oxidized LDL particles are thought to play an early and critical role in atherosclerogenesis. Hyper-low-density lipoproteinemia is one of the risk factors for cardiovascular disease, but small, dense LDL particles have been associated with an increased risk for cardiovascular disease. Small, dense LDL correlates with some cardiovascular risk factors such as diabetes mellitus, hypertriglyceridemia, hypo-high-density lipoproteinemia, and hypertension. Although smoking is also a major risk factor for cardiovascular disease, the relationship between smoking and small, dense LDL particles has not been described previously. Our cross-sectional study examined this relationship in a population of 18 healthy young adult men (9 smokers and 9 never-smokers, aged 21-24 years) from the same college. Concentrations of blood lipids and the LDL migration index (LDL-MI) were examined. Although concentrations of blood lipids did not differ between smokers and never-smokers, the LDL-MI had a strong tendency to be lower in smokers. The LDL-MI is larger in the presence of a greater proportion of small, dense LDL particles. These results indicate that tobacco smoking is associated with a decrease in the proportion of small, dense LDL particles. Regardless of these surprising results, we do not recommend smoking, given that it is a major cause of cardiovascular disease. 相似文献
102.
We revisit the Anisotropic Kepler Problem (AKP), which concerns with trajectories of an electron with anisotropic mass term
in a Coulomb field. This is one of the most fundamental fields in Quantum Chaos. Nowadays various quantum systems are challenging
us. Classical theories of these may have chaos. Quantum mechanics have developed from integrable cases and may have to be
reformulated for such cases. AKP then serves as a suitable testing ground for quantum chaos. We first review a pioneering
work by Martin Gutzwiller (J Math Phys (1977) 18:106). We shall show the systematics of the trajectories using ample figures
from an extensive numerical analysis. Then we focus on the rolê of hyperbolic singularities and we comment on the approximations
in an analytic formulation.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
103.
K. Kawanishi A. Tsuge K. Kuwabara O. Ukai N. Nakamori 《Nuclear Engineering and Design》1990,120(2-3):259-269
Scaled experiments on small break, loss-of-coolant accidents have been conducted. The tests simulated loss-of-coolant accidents (LOCAs) resulting from a 0.53% and a 0.13% communicative break in the cold leg and the pressurizer power operated relief valve (PORV). The thermal-hydraulic behavior such as natural circulation and reflux condensation cooling during a small break LOCA has been investigated.
A new computer program CANAC-II (a Computer Analysis Program of Natural Circulation for multi-loop systems) has been developed and verified based upon comprehensive tests. A drift flux model was applied for two-phase flow in CANAC-II. It also has a shorter computer running time than the real time. 相似文献
104.
Kazuhiro Umetani 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(4):521-530
This paper proposes a novel method for deriving dual converters, namely deriving current‐source converters from voltage‐source counterparts, and vice versa. The conventional derivation method is based on the transformation of circuit topology, in which series connections are converted into parallel connections, and vice versa. However, this method cannot be directly applied to nonplanar circuits because they do not allow perfect topological transformation, although many of them are known to have duals. Lagrangian dynamics does not depend on the topological relation to transform a system into another equivalent system; therefore, it possibly avoids problems related to topological transformation and may provide a universal and systematic method that can be consistently applied to nonplanar circuits. This paper discusses the derivation of duals using Lagrangian dynamics. Along with the theory, this paper presents two examples of Lagrangian derivation of duals. One derives a dual of a planar circuit, to which the topological transformation is applicable. The other derives two duals of a nonplanar circuit. Consequently, these examples suggest that the proposed method is a prospective candidate for universal and systematic derivation of duals. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
105.
为获得性能良好的镍铁钨合金镀层,研究了镀液pH 值、温度、电流密度、稳定剂抗坏血酸浓度对镍铁钨合金镀层成分和镀层沉积速率、显微硬度的影响。结果表明: 镀液pH 值对镀层W含量和镀层沉积速率影响较大;镀液温度对镀层沉积速率、镀层成分和镀层硬度影响均较大;随抗坏血酸浓度增加,镀层沉积速率逐渐降低,镀层表面形貌更加粗糙。在镀液pH = 4,温度60 ℃,电流密度4 A/dm2,抗坏血酸浓度3 g /L 时,镀层沉积速率和镀层的显微硬度较高,表面光亮致密,耐蚀性好。 相似文献
106.
Chengxin Peng Li Yang Shaohua Fang Jixian Wang Zhengxi Zhang Kazuhiro Tachibana Yong Yang Shiyong Zhao 《Journal of Applied Electrochemistry》2010,40(3):653-662
The electrochemical behaviors of copper current collector in 1-alkyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl] imide
ionic liquid electrolytes were investigated and compared with that in ethylene carbonate/dimethyl carbonate solutions. Cyclic
voltammetry results showed that large oxidation–reduction current of the copper foil appeared in ethylene carbonate/dimethyl
carbonate solutions, while a much smaller current in the room temperature ionic liquid electrolytes decreased gradually, indicating
that the copper foil was anodically stable. Further study by X-ray photoelectron spectroscopy analysis showed that an unstable
product was composed mainly of the carbonate and carbonyl species on the surface of the copper foil after the electrochemical
measurement in ethylene carbonate/dimethyl carbonate solutions, leading to the dissolution of the copper foil. While a better
passivating film from the reduction of the anions in the room temperature ionic liquid electrolytes covered the surface of
copper foil and protected the copper foil from being oxidized even in a higher potential. These results indicate that the
use of room temperature ionic liquid electrolytes can improve the stability of copper current collector in the advanced lithium
ion batteries. 相似文献
107.
Kuniaki Kawaguchi Kazuhiro Mizuguchi Katsutoshi Suzuki Hideaki Sakamoto Toshio Oguni 《应用聚合物科学杂志》2010,118(4):1910-1920
We investigated the mechanical and physical characteristics of composites composed of polyacetal [alternatively called polyoxymethylene (POM)] and cellulose fiber (CelF) derived from wood pulp [10–52 wt % (9.3–50.1 vol %)] without any fiber surface treatment. The modulus, deflection temperature under load, and thermal conduction coefficient of the POM/CelF composites were effectively enhanced with increasing CelF content, and the composites had an advantage of specific modulus compared to glass fiber (GF)‐filled POM. The flexural modulus of POM/CelF 40 wt % (38.2 vol %) was measured to be about 6 GPa, which was comparable to that of POM/GF 20 wt % (12.1 vol %). In the composites, the CelFs were distributed randomly as monofilaments, and the debonding of the interface between the fibers and POM matrices in the fracture faces was confirmed as less by scanning electron microscopy observation. The POM/CelF composites possessed lower specific wear rates than the POM/GF composites, and they had damping behaviors near that of neat POM. No clear dependence of the melt flow index of the base POM on these characteristics was observed, except on Charpy impact strength. The composites studied here were unique in their performance and ability to be designed in accordance with specific demands, and they could be potential replacements for mineral‐filled and GF‐filled POM composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
108.
采用无偏振片反射式LCD及超低功耗驱动技术制造移动显示器件 总被引:1,自引:1,他引:0
Kiyoshi Minoura Yasushi Asaoka Eiji Satoh Takashi Satoh Ichiro Ihara Sayuri Fujiwara Akio Miyata Yasuhisa Itoh Seijiro Gyoten Noboru Matsuda Yasushi Kubota 代永平 《现代显示》2010,(7):5-9,35
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。 相似文献
109.
Chinatsu Okamura Takashi Ueda Kazuhiro Hasezaki 《Journal of Electronic Materials》2010,39(9):2172-2175
Single-phase β-Zn4Sb3 materials were prepared by mechanical grinding (MG). Source materials for the Zn4Sb3 ingots were prepared using three different processes after the direct melting of constituent elements. In process 1, the
ingot was obtained by quenching the melt in water within an evacuated quartz ampoule. In process 2, the ingot was heat-treated
for 100 h at 723 K after process 1. In process 3, the ingot was heat-treated for a total of 200 h in two stages at 723 K and
673 K after process 1. The resultant ingots were mechanically ground and sintered at 623 K by hot pressing. The sintered materials
were characterized by x-ray diffraction, differential thermal analysis (DTA), and thermoelectric property measurements. The
thermal conductivity of the sintered materials was 0.88 W m−1 K−1 at room temperature, being slightly lower than that reported for the materials prepared by a conventional method. Results
indicate that the dimensionless figure of merit of the single-phase β-Zn4Sb3 ranged from 1.06 to 1.31 at 573 K. 相似文献