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91.
Characterization and Food Application of an Amperometric Needle-Type L-Lactate Sensor 总被引:1,自引:0,他引:1
There have been increasing needs for biosensing in the food industry because it is accurate, rapid and efficient. A needle-type L-lactate sensor with a three-layer membrane system which uses lactate oxidase as the biological component was prepared. The sensor had an optimum pH around 9–10 and an optimum temperature at 45 C. The current response was stable over 40 days and specifically responded to L-lactic acid. The sensor gave accurate L-lactate measurements in kimchi and yogurt of 187.4 ± 4.1 and 734.1 ± 34.5 mg/dL, similar to those of a spectrophotometric L-lactate kit. 相似文献
92.
The changes in the size and shape of soybean protein bodies in different solvent systems were observed, and their influence on hydrodynamic properties in solutions was investigated by capillary viscometer. The intrinsic viscosity of the isolated protein bodies varied with the type of dispersion media; 0.036 cm3/g in CCI4-benzene solution, 0.355 cm3/g in 50% glycerol-water mixture, 0.574 cm3/g in water at pH 7, and 1.18 cm3/g in the aqueous solution at pH 12. The hydration of the protein bodies in different dispersion media was estimated by Oncley's method and Mooney's method. The estimated degree of hydration agreed well with the swelling of the protein bodies as observed by microscope. 相似文献
93.
94.
Kyo-Hong CHOI Kwon-Koo CHO Gyu-Bong CHO Hyo-Jun AHN Ki-Won KIM Yoo-Young KIM 《材料科学与工程学报》2007,25(6):886-891
Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD. 相似文献
95.
To increase battery life in IEEE 802.16e systems, it is essential to efficiently manage energy in mobile stations. The sleep-mode operation in power management helps to increase the life of a station by saving energy consumption. In power management, there are two important performance metrics energy consumption and the response delay of awakening medium access control (MAC) service data unit (SDU). While in a base station (BS) initiation of awakening, the two performance metrics should be simultaneously considered, in a mobile subscriber station (MSS) initiation of awakening, the response delay is not considered because it is self-operational. There performance metrics are affected by the minimum sleep interval (Tmin), the maximum sleep interval (Tmax), and the average interarrival time of awakening MAC SDUs (TI) during sleep-mode operation. Therefore, it is imperative to evaluate the two initiations of awakening depending on TI. To reach a fuller understanding of the performance, this paper shows an analytical mode and simulations results for the standard sleep-mode operation in the IEEE 802.16e MAC. 相似文献
96.
NAM-SU HUH JONG-MIN KIM YOON-SUK CHANG YOUNG-JIN KIM SEONG-SIK HWANG JOUNG-SOO KIM 《Fatigue & Fracture of Engineering Materials & Structures》2007,30(2):131-142
The present work provides an elastic‐plastic fracture mechanics (EPFM) assessment scheme for a steam generator tube with a through‐wall crack under internal pressure. Noting that the geometry and material are rather uniform for steam generator tubes, and furthermore the only loading to be considered is internal pressure, an engineering EPFM analysis method is proposed to assess through‐wall cracks in steam generator tubes. Important outcomes of the present work are closed‐form approximations for J and crack opening displacement (COD). Sufficient confidence in the proposed J and COD estimates is gained from good agreements with the finite element results over a wide range of the crack length and pressure magnitude. Another important element of the EPFM assessment is to determine relevant J‐resistance curve for steam generator tubes. To improve the accuracy of predicting tube failure, the present paper also proposes a new method to determine fracture toughness using an actual tubular specimen instead of using a standard specimen, from which J‐resistance curves of steam generator tubes are obtained. Using the proposed J and toughness estimates, maximum pressures of steam generator tubes with through‐wall crack are estimated based on EPFM analysis, which is compared with experimental results and predicted ones based on limit load approach. 相似文献
97.
ZHANG Zai-xuan WANG Jian-feng LIU Hong-lin XU Hai-fen DAI Bi-zhi LI Chen-xia LI Lan-xiao GENG Dan INSOO S. KIM 《光电子快报》2007,3(6)
A 31 km long range distributed optical fiber Raman photon temperature sensor (DOFRPTS) system have been developed based on temperature effect of the amplified spontaneous Raman scattering in fiber, and using fiber laser as a pumped source. The results show that temperature measuring uncertainty is ±2 ℃, temperature resolution is 0.1 ℃, measurement time is 432 s, spatial resolution is less than 4 m. 相似文献
98.
SANGKI HAN D. W. SHIN Y. KIM Y. P. JUN S. R. MAENG J. W. CHO 《Applied Artificial Intelligence》2013,27(2):93-127
A new hybrid system called Sphinx is presented which combines classification-based reasoning with logic programming technique. It consists of two major components: a terminological component and an assertional one. The former uses a frame-based knowledge representation scheme based on classification and the latter is a theorem prover based on Horn logic. The assertional component can also handle a first-order query language and wh-questions. A new knowledge base maintenance mechanism based on the negation as failure inference rule enables Sphinx to support incremental assertions and retractions. In addition, Sphinx provides explanation capability to help the user in developing and debugging knowledge bases. 相似文献
99.
Steady, single-phase transport characterized by high eddy diffusivity in axial direction is a special case of vessel transport phenomena which has not been studied systematically so far. In the present paper, experiments are reported for a Gorter-Mellink duct, at zero net mass flow, covering turbulent eddy transport in cold He4 pressurized beyond its thermodynamic critical pressure above 4 K. Axial transport in vertical direction is induced by gravitational buoyancy. A new phenomenological equation is proposed on the basis of quantum fluid convection postulated originally for He II below the lambda point (Goner and Mellink, 1949). Our data agree reasonably with the equation. 相似文献
100.
The electrical conductivity of pure aluminum oxynitride spinel was measured at 1300° to 1500°C under flowing nitrogen gas. The re sults for two nonstoichiometric spinel compositions can be fitted by exponential expressions with an activation energy of 116± I Wlmol. The mobilities calculated from aluminum vacancy concentrations and conductivities, 8.07x cm'/V-s, are reasonable for ionic conduction. The complex impedance plot suggests electrode double-layer effects being damped out at higher frequencies in the range 10'to lo4 Hz. 相似文献