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81.
The fatigue crack propagation rate and the fatigue threshold were investigated for transverse-butt-welded joints of the austenitic stainless steel SUS304. Specimens were of the center-cracked type. In three sets of tests the fatigue crack passed through the weld metal, and in the other two sets, through the base metal. The fatigue crack propagation properties coincided with each other at different stress ratios for the weld metal, and at the higher stress ratios for the base metal. The propagation properties improved at the stress ratio of zero for the base metal. The absence of a stress ratio effect means that the coincided properties are basic ones in which fatigue crack closure does not occur. However, fractographic appearance and surface roughness were quite different between weld metal and base metal. The coincidence of fatigue crack propagation properties in spite of the difference in fractographic features reveals that the fractographic appearance and surface roughness only have a minor effect on basic fatigue crack propagation behaviour. 相似文献
82.
F Suzuki S Miyamoto M Takita M Oshita Y Watanabe A Kakizuka S Narumiya T Taniguchi I Muramatsu 《Canadian Metallurgical Quarterly》1997,1323(1):6-11
We attempt to determine the utility of CERAD in detecting early Alzheimer's disease (AD). CERAD battery was administered to a group of 14 control subjects, 12 patients with possible dementia prodromes and to patients with Alzheimer's disease stratified according to severity (16 mild, 8 moderate). Other measures as some subtest of the Wechsler memory scale and the Rey Complex Figure Test were also applied. Delayed recall as well as logical memory of Wechsler memory scale were found to be the best discriminators for detecting very mild cases of AD (Prodromes) (p < 0.05). None of the memory test proved of value in staging the disorder. Visuospatial functions are better determinants of the progression of the illness. Fluency also distinguish between control subjects and very mild cases. These findings suggest that delayed recall memory and probably executive function are the most useful and sensitive indicators of Alzheimer's disease. 相似文献
83.
84.
Tanaka K. Suzuki R. Emaru T. Higashi Y. Wang H.O. 《Mechatronics, IEEE/ASME Transactions on》2007,12(5):565-570
This paper presents an experimental study on the development of a cyclogyro-based flying robot with a new variable angle of attack mechanism. A cyclogyro is a flying machine supported in the air by power-driven rotors that rotate about a horizontal axis, like the paddle-wheels of a steamboat. Machines of this type have been designed by some companies but there has been no record of any successful flights. Our design starts with a new variable angle of attack mechanism with an eccentric (rotational) point in addition to a rotational point connecting to a motor. The main feature of the mechanism with the eccentric rotational point is the ability to change attack of angles in accordance with the wing positions (as determined by the rotational angles of the cyclogyro) without actuators. The design parameters (wing span, the number of wings, and eccentric distance) of the flying robot are determined through a series of experiments. Experimental results show that the cyclogyro-based flying robot with the new variable angle of attack mechanism is capable of generating sufficient lift force for flying. 相似文献
85.
J Yoshinaga JZ Li T Suzuki K Karita M Abe H Fujii J Mishina M Morita 《Canadian Metallurgical Quarterly》1991,31(2):159-170
Multielement analysis was performed on human milk collected on 5-9-d postpartum from 51 Japanese females using inductively coupled plasma (ICP) mass spectrometry (MS), ICP atomic emission spectrometry (ICP-AES) and fluorometry. Thirty-one elements were detected by these analytical methods in milk. Twelve elements (Na, Mg, P, S, K, Ca, Cu, Zn, Se, Sr, Rb, and Mo) were detected in all of the samples. Al, Cs, and Ba were the elements detected by ICP-MS in more than half of the samples. Multiple regression analysis extracted biological attributes of mother and infant, such as maternal stature, maternal wt, or infant's birth wt, as statistically significant factors contributing to the variation in elemental concentration in milk. However, the rates of contribution were small in all cases. It was concluded that the biological attributes of mother and infant examined in this study were not the major factors that contribute to elemental variation in human milk. 相似文献
86.
Acute hepatic failure models with extensive hepatic necrosis and hyperammonemia were developed in small animals. One model is bases on the retrograde infusion of ethanolamine oleate into the common bile duct of guinea pigs and another is based on the infusion of TNF-lipiodol emulsion into the portal tract of rats. 相似文献
87.
S Suzuki M Saito N Suzuki H Kato N Nagaoka S Yoshitake Y Yui C Kawai 《Canadian Metallurgical Quarterly》1993,22(6):834-840
We examined the thrombolytic properties of a novel modified human tissue plasminogen activator (PA) (E6010), in which cysteine 84 is replaced by serine, and which has a prolonged biologic half-life (t1/2). We compared the thrombolytic efficacy of continuous intracoronary (i.c.) infusion of E6010 with that of recombinant human tissue PA (rt-PA) in a canine model with copper coil-induced 1-h-old coronary artery thrombi and also compared the relation between thrombolytic efficacy and plasma clearance represented by pharmacokinetic parameters of i.c.-infused E6010 and rt-PA. Sixty-minute E6010 and rt-PA i.c. infusions were compared. The thrombolytic effects of i.c.-infused E6010 and rt-PA, represented by time to reperfusion (TR), reperfusion rate at 60 min (RR), and reocclusion rates at 60 min after reperfusion (OR) were as follows. E6010: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 25 +/- 10, 15 +/- 10, 13 +/- 5 (min); RR 100, 100, 100 (%); and OR 0, 0, 17 (%), respectively. Recombinant t-PA: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 47 +/- 12, 18 +/- 17, 14 +/- 4 (min); RR 50, 75, 100 (%); and OR 100, 33, 33 (%), respectively. These findings indicate that E6010 has more potent thrombolytic activity than rt-PA.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
88.
Tomoyasu Nakamine Shugo Suzuki Kenji Nakao Makoto Okazaki 《Fullerenes, Nanotubes and Carbon Nanostructures》1995,3(4):389-398
respectively. 相似文献
89.
An organic microcavity laser, in which all the stacked polymer layers are doped with pyrromethene-567 dye, is presented. Singlemode laser oscillation at 568 nm was obtained that was located in the middle of the stopband. The lasing threshold was found to be 260 nJ/pulse, which corresponded to 300 muJ/cm2 in the pulse energy density 相似文献
90.
We report the growth kinetics of the4He crystals with a small amount of3He impurities around 0.8 K. The growth resistance was measured using the response of the charged interface with respect to
an externally applied voltage. In 5 ppm and 10 ppm3He mixtures, it is found that (1) the relaxation process can be expressed as an exponential behavior, (2) the growth resistance
becomes larger compared to pure4He and does not have a strong3He concentration dependence, and (3) the temperature dependence of the growth resistance is much the same as pure4He. We discuss several possible explanations of the present experiment. 相似文献