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471.
Glucose oxidase and peroxidase were immobilized individually or simultaneously on aminated latex particles by using sodium meta-periodide and borohydride. The amount of immobilized enzymes and their activity depended on the surface potential of particles and the surface density of their own, respectively. In the simultaneous immobilization of two enzymes, the predominant immobilization of peroxidase is attributed to higher carbohydrate content in peroxidase compared with that in glucose oxidase. Simultaneously immobilized enzymes worked better in the determination of glucose than the mixture of separately immobilized ones because of the close proximity of the two enzymes.  相似文献   
472.
473.
Time-dependent dielectric breakdown (TDDB) measurement by constant current stress has been performed to investigate the oxide (SiO/sub 2/) reliability grown on n-type 4H-SiC. At 300K, the intrinsic injected charge to breakdown (Q/sub BD/) of thermally grown SiO/sub 2/ in wet O/sub 2/ ambience is about 0.1 C/cm/sup 2/, whereas N/sub 2/O anneal after the thermal oxidation results in the drastic improvement of the reliability. The intrinsic Q/sub BD/ of N/sub 2/O annealed SiO/sub 2/ is found to be 10 C/cm/sup 2/, which is two orders of magnitude larger than that of the oxide without N/sub 2/O anneal, suggesting that the quality of SiO/sub 2/ and/or SiO/sub 2//SiC interface is improved. TDDB measurement has been also performed at high temperatures up to 423 K. The activation energy of oxide lifetime estimated from time to failure of 80% is 0.35 and 0.10 eV for the oxide with and without N/sub 2/O anneal, respectively.  相似文献   
474.
Image analysis of videographs of nail fold capillaries was performed in patients with systemic sclerosis (SS), and the capillary patterns were defined by canonical discriminant analysis. Forty-eight of 55 SS patients were significantly differentiated from patients with systemic lupus erythematosus and normal controls. Normal controls and patients with systemic lupus erythematosus showed identical nail fold capillary patterns; in patients with dermatomyositis the pattern was similar to that of SS. The canonical discriminant analysis revealed that only 5 of 55 (9%) SS patients showed a normal capillary pattern. The abnormal capillary pattern in SS patients correlated with microvascular disturbances such as Raynaud's phenomenon, digital pitting scars and low finger temperature. Our results indicate that quantitative analysis of the nail fold capillaries is useful in evaluating the microvascular disturbances in SS patients.  相似文献   
475.
We reported a case of an abrupt hypotension and hypoxemia which lasted more than 60 min due to emboli of tumor at the orifice of the pulmonary artery during operation. Although the emboli were removed under the cardiopulmonary bypass (CPB) and later the patient regained good respiratory and hemodynamic conditions, he had a disturbance of consciousness after the operation. We began oxygen hyperbaric therapy (OHP) from the 6th postoperative day under spontaneous ventilation. His consciousness improved quickly after the beginning of OHP. We conclude that OHP and CPB might be useful to treat the postoperative disturbance of consciousness due to hypotension and hypoxemia during operation.  相似文献   
476.
477.
The requirements for a smart optical receiver are discussed, and a design architecture suitable for introducing ICs based on automatic decision threshold setting and retiming phase alignment using digital/analog signal processing feedback is proposed. With the proposed architecture, the decision threshold level and the retiming clock phase of received data in the decision circuit are automatically adjusted to the optimum position. This obviates the need for decision threshold level and retiming clock phase adjustments in production testing, and it reduces the power penalty (receiver sensitivity degradation) on the received optical waveform variation. The power penalty caused by temperature and supply-voltage variations and aging in installation is also reduced. The performance of the proposed architecture is estimated; the power penalty as compared with the manual optimum adjustment is less than 0.4 dB, and the robustness to avalanche photodiode multiplication factor variations and crosstalk are improved  相似文献   
478.
Nickel catalyst exhibited an extremely high activity in the gasification of some low rank coals at a temperature as low as 750 K. Approximately 85% of Yallourn coal was converted within 30 min in steam at 773 K. A high nickel loading, > 4 wt% was necessary. It seems essential for coal high in oxygen and low in sulphur to be gasified in this manner. Oxygen-containing functional groups on the coal surface seemed to play an important role in keeping the nickel catalyst in a finely dispersed state. Hydrogen sulphide was strongly adsorbed on the nickel catalyst and retarded this reaction. Hydrogen and carbon dioxide were the main products of low-temperature steam gasification. Similar low-temperature gasification reactions were also observed in hydrogen and in carbon dioxide.  相似文献   
479.
13 New 3-aryl-5-benzylidene-2-thiohydantoins were obtained by condensation of 3-o-tolyl- and 3-m-to?yl-2--thiohydantoin with aromatic aldehydes. The structure of the obtained compounds was confirmed by IR spectra. Derivatives of 2-thiohydantoin 1-13 show weak anticonvulsant activity in pentetrazole test and show no protecting activity against the maximal electric shock.  相似文献   
480.
In chemical plants, an anticorrosion magnetic drive pump is commonly used to deliver corrosive chemical liquids because of its high anticorrosion performance. However, when bubbles enter the chemical pump and accumulate between the shaft and the bearing, the shaft is often broken by thermal shock. The magnetic bearing which holds the rotor in noncontact has the advantage of avoiding thermal shock and keeping the rotor in a stable state by restoring force induced from the eddy current in the conductor. A model of magnetic bearing was analyzed using the three‐dimensional finite element method. In this model, a restoring force of 68.6 N and a braking torque of 8.7 N‐m were found. The locus of the rotation axis was also estimated using a radial load and a drag coefficient. The rotor may be located inside the movable range. ©2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 80–87, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20652  相似文献   
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