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121.
J. A. Knapp T. R. Guilinger M. J. Kelly B. L. Doyle D. Walsh S. S. Tsao 《Journal of Fusion Energy》1990,9(4):371-375
Electrochemical cells constructed with a thin Pd or Ti foil electrode mounted at one wall of the cell have been used both to test for the existence of cold fusion and to measure directly DPd loading ratios in an operating cell. The first type of experiment used a surface-barrier particle detector positioned a few millimeters from the foil to provide a very sensitive monitor for possible fusion-generated protons at 3.02 MeV. The detection limit for this arrangement is estimated to be 10–24 fusions/deuterium/s, assuming a bulk fusion effect. These experiments included cells with 5- and 25-m-thick Pd foils, 10-m Ti foils, parallel experiments with 0.1M LiOD (heavy water) in one cell and LiOH (light water) in another, current densities up to 0.5 A/cm2, and run times as long as 22 days. No evidence for fusion products was seen. The second type of experiment using these cells, both as an adjunct to the fusion tests and to provide new information, was the use of external beam nuclear reaction analysis to monitor directly the loading and unloading of deuterium in the foil of an operating cell. Using a 1.5-MeV3He ion beam in air, the deuterium in the outer 2 m of the exposed Pd foil was measured for the first time using the D(3He,p) nuclear reaction. The maximum DPd ratios observed using this technique were 0.8–0.9. 相似文献
122.
Francis H. C. Tsao 《Lipids》1986,21(8):498-502
The effect of cytidine 5′-monophosphate (CMP) on the incorporation of cytidine 5′-diphosphate (CDP) [methyl-14C]choline or [1-14C]dipalmitoylglycerol into phosphatidylcholine (PC) catalyzed by rabbit lung microsomal CDP choline:1,2-diacyl-sn-glycerol cholinephosphotransferase (EC 2.7.8.2) was studied. In the presence of 0.85 mM CMP and nonsaturating diacylglycerol
concentration, the incorporation of CDP[14C]choline into PC was markedly stimulated, but the incorporation of [14C]dipalmitoylglycerol into PC was inhibited. This was due to the increase of endogenous diacylglycerol generated from microsomal
PC by the cholinephosphotransferase reverse reaction. However, the newly synthesized PC was not readily hydrolyzed in the
presence of CMP. The results of this study suggest that the endogenous membranous diacylglycerol is utilized more preferentially
for PC synthesis than the exogenous diacylglycerol and that the newly synthesized PC could rapidly equilibrate with the endogenous
membrane PC pool. 相似文献
123.
The microstructure and corrosion properties of Ti7CuxSn (x?=?0–5?wt-%) alloys after solution treatment have been investigated. The alloys were solution-treated (ST) at 1000°C for 2?h, followed by quenching in water to room temperature. It was found that the microstructure of the ST Ti7Cu alloy had only a martensite structure, and that addition of Sn could refine the microstructure of Ti7CuxSn alloy. Notably, the pseudo dendritic α-Ti phase was formed in ST Ti7Cu5Sn alloys. Potentiodynamic polarisation curves and electrochemical impedance spectroscopy data demonstrated that adding Sn improved the electrochemical corrosion behaviour of the Ti7CuxSn alloy. 相似文献
124.
T. L. Su S. S. Wang L. C. Tsao S. Y. Chang T. H. Chuang M. S. Yeh 《Journal of Materials Engineering and Performance》2002,11(2):187-193
The corrosion behaviors of a series of Al-Si-Cu-based filler metals and the 6061-T6 butt joints brazed with these filler metals
are evaluated by polarization tests and immersion tests in a 3.5% NaCl aqueous solution. For comparison, a traditional Al-12Si
filler metal is also employed. The results indicate that the Al-Si-Cu-based filler metals before brazing possess much higher
corrosion current densities and pitting tendencies than the Al-12Si filler metal. However, brazing of the 6061-T6 alloy with
an Al-12Si filler metal produces a wider butt joint, which, in this case, creates a more extensive corrosion region. Severe
galvanic corrosion occurs at the 6061-T6 joints when brazed with Al-Si-Cu-based filler metals. However, in the case of the
6061-T6/Al-12Si brazements, selective corrosion of the Al-12Si eutectic phase can be observed. The bonding strengths of the
6061-T6 butt joints brazed with various filler metals are also measured before and after the immersion tests. 相似文献
125.
126.
Kok-Khun Yong Jer-Hwa Chang Ming-Hsien Chien Shih-Ming Tsao Ming-Chih Yu Kuan-Jen Bai Thomas Chang-Yao Tsao Shun-Fa Yang 《International journal of molecular sciences》2016,17(2)
Monocyte chemoattractant protein (MCP)-1 increases in the serum of immunocompetent patients with community-acquired pneumonia (CAP). However, the correlation between the circulating level of MCP-1 and severity of CAP remains unclear. This study investigated differential changes in the plasma MCP-1 levels of patients with CAP before and after an antibiotic treatment and further analyzes the association between the CAP severity and MCP-1 levels. We measured the plasma MCP-1 levels of 137 patients with CAP and 74 healthy controls by using a commercial enzyme-linked immunosorbent assay. Upon initial hospitalization, Acute Physiology and Chronic Health Evaluation II (APACHE II); confusion, urea level, respiratory rate, blood pressure, and age of >64 years (CURB-65); and pneumonia severity index (PSI) scores were determined for assessing the CAP severity in these patients. The antibiotic treatment reduced the number of white blood cells (WBCs) and neutrophils as well as the level of C-reactive protein (CRP) and MCP-1. The plasma MCP-1 level, but not the CRP level or WBC count, correlated with the CAP severity according to the PSI (r = 0.509, p < 0.001), CURB-65 (r = 0.468, p < 0.001), and APACHE II (r = 0.360, p < 0.001) scores. We concluded that MCP-1 levels act in the development of CAP and are involved in the severity of CAP. 相似文献
127.
Organometallic vapor phase epitaxy (OMVPE) 总被引:3,自引:0,他引:3
William G. Breiland Michael E. Coltrin J. Randall Creighton Hong Q. Hou Harry K. Moffat Jeffrey Y. Tsao 《Materials Science and Engineering: R: Reports》1999,24(6):241-274
Organometallic vapor phase epitaxy (OMVPE) has emerged in this past decade as a flexible and powerful epitaxial materials synthesis technology for a wide range of compound–semiconductor materials and devices. Despite its capabilities and rapidly growing importance, OMVPE is far from being well understood: it is exceedingly complex, involving the chemically reacting flow of mixtures of organometallic, hydride and carrier-gas precursors. Recently, however, OMVPE technologies based on high-speed rotating disk reactors (RDRs) have become increasingly common. As fluid flow in these reactors is typically cylindrically symmetric and laminar, its effect on the overall epitaxial growth process is beginning to be unraveled through quantitative computer models. In addition, over the past several years, a combination of well-controlled surface science and RDR-based growth-rate measurements has led to a richer understanding of some of the critical gas and surface chemistry mechanisms underlying OMVPE. As a consequence, it is becoming increasingly possible to develop a quantitative and physically based understanding of OMVPE in particular chemical systems. In this article, we review this understanding for the important specific case of AlGaAs OMVPE in an RDR under conditions used for growing typical device heterostructures. Our goal is to use typical growth conditions as a starting point for a discussion of fundamental physical and chemical phenomena, beginning with the fluid flow through an RDR and ending with the chemical reactions on the surface. By focusing on one particularly important yet relatively simple specific case, this review differs from more comprehensive previous reviews. Viewed as a case study, though, it complements these previous reviews by illustrating the wide diversity of research that is related to OMVPE. It can also serve as a good starting point for the development and transfer of insights into other more complex cases, such as: OMVPE of materials families containing Sb, P or N species, of other devices types, and in other more complex reactor geometries. 相似文献
128.
Efficient solutions for discrete Asian options 总被引:1,自引:0,他引:1
Chueh-Yung Tsao Chi-Tsung Huang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2007,11(12):1131-1140
While in the literature most studies on pricing focus on continuous Asian options, in this paper we provide efficient solutions
for both European and American discrete average price Asian options. The method used for deriving the approximation formula
for European Asian options is based on the idea of Bouaziz et al. (J Bank Finance 18:823–839, 1994) and Taso et al. (J Futures
Mark 23:487–516, 2003) in which the Taylor expansion is used to obtain the approximation formula for continuous average strike
Asian options. By using the Taylor expansion to the second order, a simple and accurate solution can be obtained. The approximation
formula for the European Asian option can further be used to enhance the efficiency of the pricing of the American Asian options
when using the numerical method. 相似文献
129.
C.C. Chi L.C. Tsao C.W. Tsao T.H. Chuang 《Journal of Materials Engineering and Performance》2008,17(1):134-140
The reflow of Sn-58Bi solder joints in a BGA package with Au/Ni/Cu pads has been performed by employing various temperature
profiles, which results in the formation of (Au0.66Ni0.34)(Sn0.82Bi0.18)4 intermetallic flakes in the solder matrix. The reflow operation performed at a peak temperature of 180 °C for a melting time
of 80 s gives a ball shear strength of 9.1 N, which decreases drastically to lower values between 6.4 and 4.6 N after further
aging at temperatures from 75 to 125 °C. Double layers of intermetallic compounds with the compositions of (Au0.30Ni0.70)(Sn0.90Bi0.10)4/Ni3Sn4 can be found at the solder/pad interfaces of the aged Sn-58Bi solder joints. Ball shear testing of the reflowed specimens
shows ductile fracture through the solder matrix, which changes to brittle cleavage fracture mainly along the (Au0.30Ni0.70)(Sn0.90Bi0.10)4 intermetallic layer after aging at various temperatures. The measurement of ball shear strengths (S) reveals a linear relation with the thicknesses (X) of (Au0.30Ni0.70)(Sn0.90Bi0.10)4 intermetallic layers: S = 7.13 − 0.33X. 相似文献
130.
Suqin Shao Alison M. Duncan Raymond Yang Massimo F. Marcone Istvan Rajcan Rong Tsao 《Journal of Functional Foods》2009,1(1):119-127
Soybean seeds with three different levels (low, intermediate and high) of isoflavones were processed to soy flour and soy protein isolates (SPIs) and developed into functional soy breads. The effect of factors involved in all steps of the process was investigated by tracking the composition and concentration of native forms of isoflavones. The total isoflavone contents were 8033.3, 10570.1 and 15169.0 nmol/g DM (dry matter) in the three soybeans; 13201.5, 20034.4 and 26014.3 nmol/g DM in defatted soy flours; 9113.2, 13274.6 and 17918.3 nmol/g DM in the SPI; 2782.7, 4081.4 and 5590.3 nmol/g DM in soy breads, respectively. The bread making processes did not affect the total isoflavone content, but changed glucosides/acetylglucosides to aglycones. Malonylglucosides were stable prior to baking but degraded to acetylglucosides and further to glucosides during baking. Our results provide critical information for the production of functional soy breads that contain varying amounts of soy isoflavones. 相似文献