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131.
Differential phase distortion of the light-emitting diode is measured and analysed. An effective technique is proposed to compensate the d.p. distortion. An experimental result shows that 2.8° d.p. distortion has been reduced to within 1°. 相似文献
132.
The relations between the size of wear fragments and the sliding velocity or normal load were studied from a mechanical point of view for the unlubricated wear of nickel. It was found that the size of mean wear fragments has a definite quantitative correlation with the thickness of the plastically deformed substrate layer, irrespective of the experimental conditions. The thickness of the deformed layer is determined by the actual forces working on real contact points, which are dependent on the dynamic properties of the specific sliding system. These mechanical factors govern wear-velocity and wear-normal load characteristics. 相似文献
133.
134.
T Kimura JK Toung S Margolis WR Bell JL Cameron 《Canadian Metallurgical Quarterly》1980,87(5):509-513
Hypertriglyceridemia has been noted in patients with acute pancreatitis and respiratory failure. Utilizing an isolated, perfused, canine pulmonary lobe, the effect of triglyceride infusion on pulmonary function was evaluated. When heparin was used to anticoagulate the perfusion circuit, the addition of triglyceride to the autologous blood perfusate resulted in massive weight gain (226 gm), intrapulmonary shunting (36%), and a marked drop in pulmonary compliance (congruent to 50%). Heparin activates lipoprotein lipase, and therefore some triglyceride in the perfusate was lipolyzed with a resultant increase in serum free fatty acids (FFAs) to 253 mumole/dl. When anticoagulation of the perfusion circuit was accomplished by defibrinogenation with Arvin, the addition of triglyceride to the autologous blood perfusate caused minimal weight gain (28 gm), no intrapulmonary shunting, and only a slight decrease in pulmonary compliance (22%). Arvin has no effect on lipoprotein lipase, and the FFA level in the perfusate remained normal (less than 70 mumole/dl). Thus it appears that FFA release secondary to the action of pulmonary lipoprotein lipase on blood triglyceride is the important pathogenic step in the induction of respiratory failure in this model. 相似文献
135.
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137.
The growth and ammonium uptake of the aerial microalga Coelastrella striolata var. multistriata, which was isolated from the surface of rocks, were characterized in this study. The specific growth rate of the alga was mu=0.3 d(-1), as calculated in the growth logarithmic phase. The algal cells were able to remove almost 100% of the ammonium ions from medium in 5 d, with the removal rate of ammonium-N being 0.4 mg/l/h. It was shown that the alga has a unique ability to be a reddish orange to green color depending on the nitrogen source concentration in the medium. Astaxanthin, adonixanthin, canthaxanthin, and beta-carotene were found in the reddish orange cells of the alga. The assessment of water pollution was attempted using this aerial microalga. When the reddish orange alga was incubated in the experimental medium with added ammonium-, nitrate-, or urea-N as a nitrogen source, an approximately linear relationship existed between the nitrogen concentration and chlorophyll formation. Using the chlorophyll formation of the alga, for example, it was possible to estimate spectrophotometrically the total nitrogen content in water collected from aquatic systems. Biofunctional materials for environmental biomonitoring using photosynthetic microorganisms are called green devices in this study. 相似文献
138.
Tanaka N Kimura H Tokuda D Hosoya K Ikegami T Ishizuka N Minakuchi H Nakanishi K Shintani Y Furuno M Cabrera K 《Analytical chemistry》2004,76(5):1273-1281
Simple and comprehensive two-dimensional (2D)-HPLC was studied in a reversed-phase mode using monolithic silica columns for second-dimension (2nd-D) separation. Every fraction from the first column, 15 cm long (4.6-mm i.d.), packed with fluoroalkylsilyl-bonded (FR) silica particles, was subjected to the separation in the 2nd-D using one or two octadecylsilylated (C(18)) monolithic silica columns (4.6-mm i.d., 3 cm). Monolithic silica columns in the 2nd-D were eluted at a flow rate of up to 10 mL/min with separation time of 30 s that meets the fractionation every 15-30 s at the first dimension (1st-D) operated at a flow rate of 0.4-0.8 mL/min. Three cases were studied. (1) In the simplest scheme of 2D-HPLC, effluent of the 1st-D was directly loaded into an injector loop of 2nd-D HPLC for 28 s, and 2 s was allowed for injection. (2) Two six-port valves each having a sample loop were used to hold the effluent of the 1st-D alternately for 30 s for one 2nd-D column to effect comprehensive 2D-HPLC without the loss of 1st-D effluent. (3) Two monolithic silica columns were used for 2nd-D by using a switching valve and two sets of 2nd-D chromatographs separating each fraction of the 1st-D effluent with the two 2nd-D columns alternately. In this case, two columns of the same stationary phase (C(18)) or different phases, C(18) and (pentabromobenzyloxy)propylsilyl-bonded (PBB), could be employed at the 2nd-D, although the latter needed two complementary runs. The systems produced peak capacity of approximately 1000 in approximately 60 min in cases 1 and 2 and in approximately 30 min in case 3. The three stationary phases, FR, C(18), and PBB, showed widely different selectivity from each other, making 2D separations possible. The simple and comprehensive 2D-HPLC utilizes the stability and high efficiency at high linear velocities of monolithic silica columns. 相似文献
139.
S. Kimura F. Ogasawara Y. Suzuki R. Nomura Y. Okuda 《Journal of Low Temperature Physics》2004,134(1-2):157-162
When acoustic waves were applied to the solid-liquid interface of 4He perpendicularly, from the solid side, the solid was megted at high temperatures and grown at low temperatures. This means that the direction of the force on the interface was inverted at an inversion temperature, T i. We attributed this effect to the acoustic radiation pressure, which induced crystallization and megting [Phys. Rev. Lett. 90, 075301, (2003)]. Temperature dependence of the interface motion by acoustic waves was investigated in several surface orientations. Anisotropy of T i was found and T i was lower on a vicinal surface than on a rough surface. 相似文献
140.
S/N and error rate performance in AlGaAs semiconductor laser preamplifier and linear repeater systems 总被引:2,自引:0,他引:2
The applications of AlGaAs semiconductor laser preamplifier and linear repeaters in single mode optical fiber transmission systems were studied through the baseband signal-to-noise ratio and bit error rate performance measurement. Experiments were carried out with the Fabry-Perot cavity laser amplifiers whose characteristics are improved by reducing the input mirror reflectivity to 6 percent. The use of a preamplifier improves the minimum detectable power by 7.4 dB over the Si-APD direct detection level when the received signal is amplified by 30 dB before photodetection. The use of two linear repeaters increases the regenerative repeater gain by 37 dB. These experimental results are in good agreement with theoretical predictions based on the photon statistic master equation analysis. 相似文献