日本东北地区1999年建坝情况

１９９９ 年度政府预算案决定了建设省东北地区１９９９ 年度建坝费用。６ 个县共建造１６座坝， 总经费为２６９．３６ 亿日元。调查研究１０ 座坝， 所需经费为７．７ 亿日元。     

Compton scattering in a large-aperture positron imaging system

Compton scattering of gamma rays within the image volume has been assessed for a large-aperture positron-emission-tomography imaging system. The Compton scattered attenuation and the Compton scattered background were both modeled and measured for point sources centered in scattering spheres up to 10 cm in diameter. Good agreement was obtained between simulations and measurements. The attenuation problem is independent of the detector system, but its correction is more difficult in a large-aperture system. The scattered coincidence background is large in this system (43% for a 10-cm-diameter scattering sphere), but the background overlap is reduced with 3D imaging.     

Effect of a direct magnetic field on the interfacial microstructure between molten aluminium and solid iron

Many processing techniques, such as hot dip aluminizing, bimetal formation, liquid metal corrosion, cementing, welding and diffusion bonding, are basically dependent on interfacial reactions [1-3]. It is therefore important to investigate the formation and growth of intermetallic layers at the interface. There have been several studies carried out to examine chemical compositions and growth kinetics of intermetallic layers in the Al-Fe system [4-9]. Most authors have come to an agreement that…     

Impact of dietary n−3 FA deficiency on rat bone tissue FA composition

The effect of dietary n−3 FA deficiency on bone tissue FA composition was evaluated in growing rats. Two mixtures combining hydrogenated coconut oil with safflower oil served as the n−3-deficient dietary treatments and provided two levels of linoleic acid (LA). The n−3 treatments were formulated with added α-linolenic acid (LNA) from flaxseed oil (diet LNA) or LNA plus DHA, and both were balanced for LA. This study showed that bone is sensitive to changes in dietary n−3 FA and that DHA is more effective than LNA in maintaining DHA levels in these tissues.     

液环式氯压机气液分离器爆炸原因及对策

介绍了隔膜电解输送氯气的液环式氯压机气液分离器发生突发性爆炸的事故经过、事故原因分析、采取的措施及在短期内再次开车成功的经过。