Selective O–H Bond Cleavage in the Radiolysis of Quartz

Cleavage of the O–H bond in quartz was studied by Fourier transform infrared spectroscopy and ESR spectroscopy. When quartz single crystals and fused silica glass are γ-irradiated at 77 K, hydrogen atoms are produced by rupture of O–H bonds. The initial efficiency of O–H bond cleavage in quartz single crystals, i.e. the initial yield of H atoms, was three times as great as that in fused silica glass, although the concentration of O–H bonds in quartz single crystals (70 ppm) is much lower than that in fused silica glass (4000 ppm). The efficiency of O–H bond cleavage in quartz single crystals indicates that energy transfer from the irradiated single crystal to the O–H bonds takes place effectively at 77 K. The efficiency of O–H bond cleavage decreases with increasing γ-ray dose, i.e. with increasing amounts of radiation-induced defects in quartz single crystals. When the radiation-induced defects are removed by annealing the irradiated quartz single crystal at 773 K, the O–H bonds are ruptured again as effectively as for a fresh quartz single crystal. The distance of the energy transfer, estimated by a target model, is ∼15 nm.     

Fault diagnosis of a power system based on a description of the structure and function of the relay system

Abstract: This paper proposes a method of fault diagnosis of power systems based on a knowledge-based approach. It makes use of information on relays and circuit breakers. The feature of this method is that the relay sequence is represented by a logical circuit. In this circuit the following two relations are represented; a logical relation between inputs and output of a gate and a connective relation between logical gates. These two relations are expressed by production rules in the knowledge base. When the information from relays and circuit breakers is given to the logical circuit, faulty components are pointed out.     

Simultaneous Oxidization of NOx and SO2 by a New Non-thermal Plasma Reactor Enhanced by Catalyst and Additive

The non-thermal plasma as one of the most promising technologies for removing NOx and SO2 has attrm~ted much attention. In this study, a new plasma reactor combined with catalyst and additive was developed to effectively oxidize and remove NOx and SO2 in the flue gas. The experimental results showed that TiO2 could improve the oxidation efficiency of SO2 in the case of applying plasma while having a negative effect on the oxidation process of NO and NOx. With the addition of NH3, the oxidation rates of NOx, NO and SO2 were slightly increased. However, the effect of adding NH3 on NOx oxidation was negative when the temperature was above 200℃.     

Formation Reaction of ZrO2 Scatterers in ZrF4-Based Fluoride Fibers

This paper clarifies the formation reaction of ZrO₂ crystals which appear as extrinsic scatterers in fluoride fibers. EPMA analysis indicates that BaO exists at grain boundaries of BaF₂ purified by sublimation. BaO reacts with ZrF₄ to form ZrO₂ at 600°C during a glass-melting process. The ZrO₂ formation reaction is influenced by H₂O. Ba(OH)₂, which is formed by the reaction between BaO and water vapor, melts at 370° to 420°C and reacts with ZrF₄ to form ZrO₂ at 450° to 520°C. When low-oxide-content BaF₂ is used for fiber preparation, scatterers significantly decrease.     

Controlled Crystallization of Amorphous Si3N4by Ti and CI Additives

Thin films of amorphous Si₃N₄ were prepared by the rf-sputtering method, and the effects of titanium and chlorine additives on its crystallization were examined. When Ti-doped amorphous Si₃N₄ was heated, TiN precipitated at >1100°C; the TiN precipitates promoted the conversion of amorphous Si₃N₄ to β-Si₃N₄. Chlorine led to preferential conversion of amorphous Si₃N₄ to α-Si₃N₄.     

Development of High‐Power Density Interleaved dc/dc Converter with SiC Devices

We developed an interleaved dc/dc converter with SiC devices. We applied full‐SiC modules including MOSFETs and SBDs to the interleaved dc/dc converter to achieve a high‐power density. An SiC has a high temperature resistance, which facilitates an improvement in high‐frequency drives. We achieved a high‐power density by utilizing this high temperature resistance. We also fabricated a prototype and tested it with loads up to 65 kW.     

Hf对铁素体钢中辐照引起的晶间偏析的影响

1％Hf（质量分数）被注入E911钢中．利用250keV的Ni离子在300℃辐照含Hf和不含Hf的E911钢，以研究Hf的添加对铁素体／马氏体钢中由辐照引起的偏析的影响．结果表明，Hf的添加抑制了晶界上P原子的富集和Cr原子的贫化．讨论和评估了Hf对自由迁移的缺陷数量的影响，结合一个辐照引起的非平衡偏析（RIS）模型以预测Hf对P3Cr等元素的晶界偏析行为的作用．对预测结果和实验数据作了比较．     

PRESENT STATUS OF POWDER TECHNOLOGY EDUCATIONAL PROGRAMS AND RESEARCHES IN JAPAN

Tables to indicate the present status of powder technology educational programs in Japan are presented on the basis of a questionnaire style investigation by the Society of Powder Technology, Japan. Research activities in universities and research institutes are also included in the tables.

The activities of both the Society of Powder Technology and the Association of Powder Process Industry and Engineering in Japan are also introduced by explaining their organizations and annual events.     

迁入社区式公寓楼后居住者的生活空间变化与其隐私 意识 *

通过将LA空间模式下的社区式公寓楼与常规公寓楼在居住者的空间环境以及隐私意识这两方面的对比,本文研究评估了前者的相关效应,并发现前者比后者容纳了更多的社区行为。社区式公寓楼的居民们通过控制自己住房的边界状况来把握和解决自身隐私需求,其方法可被分为五类。本论文研究者发现,居民们并不会简单地否定或肯定来自外部的视线影响,而是在一种复杂的社会交往与空间调整中控制着他们之间那条互相作用着的界线。     

BOTULOGENIC PROPERTIES OF VEGETABLES WITH SPECIAL REFERENCE TO THE MOLECULAR SIZE OF THE TOXIN IN THEM

The molecular sizes of Clostridium botulinum type A, B, E, and F toxins produced in string beans, mushrooms, tuna fish and pork were determined to provide an explanation for the high botulogenic properties of vegetables. Type A and B organisms produced the orally more toxic 16S and 19S molecular-sized toxins in vegetables, whereas they produced the orally less toxic 12S and only rarely some 16S toxin in tuna fish and pork. Type E and F organisms produced only 12S toxin in any food or culture medium, but addition of glucose seemed essential for appreciable toxin production. It appeared that the molecular sizes of type A and B toxins transform depending upon the content of iron and manganese salts in foods.