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81.
S. Ueda  Y. Uemura 《热应力杂志》2013,36(10):1005-1023
This paper investigates the thermoelectromechanical interaction among multi parallel cracks in a piezoelectric material under a uniform heat flow and a uniform mechanical load far away from the crack region. The crack faces are supposed to be insulated thermally and electrically. By using the Fourier transform, the thermal and electromechanical problems are reduced to systems of singular integral equations, respectively. The singular integral equations are solved numerically. Numerical calculations are carried out, and detailed results are presented to illustrate the influence of the thermoelectromechanical interaction on the stress and electric displacement intensity factors.  相似文献   
82.
Efforts have been made to reproduce shitogi, a finely pounded rice powder and to make sake from shitogi of the type produced in ancient times in Japan. As the particle size of the shitogi became smaller, the rate of degradation of shitogi by glucoamylase increased. The pounding of shitogi enhanced the saccharification of starchy materials. The ancient Japanese alcoholic beverage known as shitogi sake was made with cooked rice, dry yeast and tap water, using mould‐infected shitogi as the saccharifying agent. It contained 10.7–14.3% ethanol (v/v) and had a fine aroma but a sour taste. We believe that we have reproduced the alcoholic beverage, shitogi sake which might have been one of original Japanese alcoholic beverages.  相似文献   
83.
合金元素和显微结构对CO2/H2S环境中腐蚀产物稳定性的影响   总被引:11,自引:1,他引:11  
石油天然气工业的耐蚀合金(CRAs)设计要考虑腐蚀产物的稳定性.通过电位-pH图,以及FeCO3、氧化物和硫化物溶解度的计算,评价了在CO2/H2S环境中钢铁表面生成的腐蚀产物的稳定性.在CO2的环境中,碳钢的局部腐蚀与腐蚀产物FeCO3的形成有关.含有铁素体-珠光体显微结构的J55钢可以耐CO2腐蚀,是因为层状渗碳体可以稳固表面形成的腐蚀产物.铬钢是CO2环境中的耐蚀材料,因为表面能生成黏附性非晶铬氧化物的腐蚀产物.当H2S的含量超过CO2的分压为100×10-6时的对应含量时,从腐蚀产物FeCO3和FeS的稳定性来看,其腐蚀就变成H2S的腐蚀类型.在H2S环境中,耐蚀合金腐蚀产物的稳定性与铬的氧化物和硫化物(如FeS,Ni3S2和MoS2)的生成有关.  相似文献   
84.
Selective as well as waste forming active centers were defined for MoVNbTeO and MoVTaTeO catalysts in the ammoxidation of propane to acrylonitrile and all catalytic functionalities were assigned to specific elements at the respective active centers. Symbiosis between M1 and M2 phases of these catalysts was observed, with phase cooperation being more extensive in the Nb than Ta containing compositions. The difference in catalytic effectiveness arises most likely because contact and surface area exposure of the two respective, cooperating phase pairs are not equal. The M1 phase of the catalysts is reducible by propane and ammonia in the absence of dioxygen and is regenerable to its original, fully oxidized state by dioxygen (air). No structural collapse is observed even after 120 C3H8 + NH3 reduction pulses. The so induced reduction of the catalyst extends up to 70 layers deep. The product distribution over the first few pulses is very similar to that under catalytic conditions, supporting the concept that lattice oxygen is involved in the catalytic ammoxidation process. Therefore, the ammoxidation of paraffins is a redox process, as is of course the well-known olefin ammoxidation process.  相似文献   
85.
A 78-year-old female was admitted with complaints of malaise and fatigue in the legs. The patient was diagnosed as severe aplastic anemia and treatment was started with metenolone and steroid pulse therapy. Administration of antibiotics and granulocyte-colony stimulating factor which led to a resolution of the high fever. About four months after admission, the patient developed vomiting and abdominal pain with a spiking fever. The next day after suddenly losing consciousness, she died. B. cereus was isolated from blood cultures. Autopsy specimens of the liver, cardiac muscle and lung showed changes due to B. cereus. This pathogen is widely distributed in nature. We should not overlook B. cereus as a contamination, but rather should consider it a potential pathogen in immunocompromised hosts, when it is isolated from blood cultures.  相似文献   
86.
From the aspects of economical competitiveness, proliferation resistance, and minimizing waste problems, PNC has proposed an improved recycle concept for the FBR fuel cycle, termed Advanced Fuel Recycle System. Reprocessing in this system is based on the well-known PUREX flowsheet and features a “single cycle Pu/U co-extraction flowsheet” with lower decontamination factor (DF) than that in the conventional process. This feature is practical because of the FBR's low neutronic sensitivity to impurities.

Such a simplified extraction process without purification cycles should substantially reduce not only the number of process components but also the quantities of liquid to be treated in other related processes, so it will lead to the proportional reduction in waste processing, waste itself, and all other related equipments and facilities. This should improve overall economics. One method being examined to further reduce the liquid throughputs and simplify the process is to apply the crystallization technique to dissolver solution.

Overall, with this proposed concept, proliferation resistance will be significantly improved because plutonium is always recovered as a mixture with the uranium and DF of the plutonium product is low.

Reprocessing and fabrication processes are integrated into one fuel cycle plant in this system further contributing to these improvements.  相似文献   

87.
The application of superconductivity technology to electric power apparatus is very important from the viewpoint of energy saving. Especially, the superconducting generators using superconductors as the field windings have many merits compared with conventional generators. Super-GM has been researching and developing 70-MW-class model machines since FY 1988 for a scheduled period of eight years, aiming at a 200-MW-class superconducting generator. This paper describes the basic specifications and designs of 70-MW-class superconducting generators by Super-GM and also describes the propriety of these basic specifications and designs.  相似文献   
88.
89.
PURPOSE: The dialysability of ioversol was investigated in 12 patients with chronic renal failure, on 4-h hemodialysis. MATERIAL AND METHODS: One hundred ml of ioversol (320 mg I/ml) was injected in less than 10 min during CT. Hemodialysis was commenced within 30 min of starting the contrast medium injection and was continued for 4 h. Blood was sampled before and at 15 min, 30 min, 1 h, 2 h, and 4 h after the start of hemodialysis. Mean dialysance of ioversol was 114 to 129 ml/min and the elimination rate was 82.5 +/- 5.1% 4 h after starting hemodialysis. The half-life of ioversol during hemodialysis was 1.80 +/- 0.38 h. The only side effects of the ioversol injection were heat sensations, which were experienced by 3 patients. RESULTS: As ioversol was effectively removed from the body during the 4 h of hemodialysis and no severe adverse reactions were observed, we conclude that ioversol is suitable for use in hemodialyzed patients.  相似文献   
90.
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