A Quantitative Analysis of Energy Dissipation among Three Typical Air Entrainment Phenomena

This study investigates energy dissipation due to air bubble entrainment for three typical phenomena; a hydraulic jump, a 2-D vertical plunging jet and a vertical circular plunging jet into water. A simple model is presented here which enables to estimate the energy transformation and dissipation achieved by air bubbles quantitatively for three above phenomena. The average rate of energy dissipation by air bubbles obtained from the experimental data are 25%, 1.4%, and 2.15% with respect to total energy loss for the hydraulic jump, 2-D vertical plunging jet and vertical circular plunging jet, respectively.     

日本职业卫生管理及对中国的启示

依据中日合作项目《加强中国国家安全生产科学技术能力计划》成果，系统介绍了日本职业卫生监管机构、法规、职业病确定、作业环境管理等。同时，结合中国职业卫生管理体制尚未完全理顺、法规较滞后、专业人才不足、企业基础资料不全和自主管理体制不健全等现状，提出了进一步明确职业卫生管理体制、完善职业卫生法规、建立职业卫生统计制度、强化企业自主管理能力等建立健全中国职业卫生管理的对策和建议。本文对完善中国职业卫生管理具有重要的参考意义。     

日本职业卫生管理及对中国的启示

依据中日合作项目<加强中国国家安全生产科学技术能力计划>成果,系统介绍了日本职业卫生监管机构、法规、职业病确定、作业环境管理等.同时,结合中国职业卫生管理体制尚未完全理顺、法规较滞后、专业人才不足、企业基础资料不全和自主管理体制不健全等现状,提出了进一步明确职业卫生管理体制、完善职业卫生法规、建立职业卫生统计制度、强化企业自主管理能力等建立健全中国职业卫生管理的对策和建议.本文对完善中国职业卫生管理具有重要的参考意义.     

Degree-day accumulation controlling allopatric and sympatric variations in the sociality of sweat bees, <Emphasis Type="Italic">Lasioglossum</Emphasis> (<Emphasis Type="Italic">Evylaeus</Emphasis>) <Emphasis Type="Italic">baleicum</Emphasis> (Hymenoptera: Halictidae)

Halictine bees exhibit a wide range of social behaviour that varies both inter- and intraspecifically. Although previous studies suggested that the intraspecific variation might be attributed to temperature differences, there was no direct evidence to detect the relationships between temperature and socialities. Lasioglossum (Evylaeus) baleicum exhibited solitary behaviour in a cooler locality (Kawakita) because of the shorter breeding season; in a warmer locality (Nishioka Park), however, this bee species exhibited eusociality at sunny site and solitary behaviour at shady site, whereas a molecular phylogeny confirms that all of these colonies are evidently conspecific. Therefore, we examined the effect of degree-day accumulation on the sympatric social variation of L. baleicum by rearing the bees to calculate the threshold temperature. Whereas they showed high mortality, the threshold temperature was estimated to be 10.33°C and the expected degree-day accumulation was 340 degree days. When we use this value of a degree-day accumulation to estimate the expected eclosion date, the estimated dates were always consistent with observed eclosion dates. In any sites where the bees were solitary, the degree-day accumulation was not enough for the second eclosion by the end of the bee-active season. In Nishioka Park, sex ratio of the first brood was female biased, and daughters were smaller than mothers; in Kawakita, however, there was no sex bias, and daughters were as large as their mothers indicating that the foundresses seem to produce gyne-sized females in Kawakita but worker-sized females in Nishioka though these females do not become workers at shady site.     

Paraben-chlorinated derivatives in river waters

This article reports the first identification of paraben-chlorinated derivatives in river water. Parabens are widely used as preservatives in pharmaceuticals and personal care products. Parabens can be easily chlorinated by chlorinated tap water. The resulting chlorinated derivatives might pose a higher potential risk to humans and ecosystems than the corresponding parent parabens. However, the occurrence of such derivatives in rivers remains unknown so far. We studied 23 parabens and their chlorinated derivatives from rivers receiving effluents from sewage treatment plants in Shizuoka city, in the central Pacific region of Japan. The compounds were extracted by solid-phase extraction with a styrene polymer sorbent, trimethylsilyl-derivatized, and then identified by gas chromatography–mass spectrometry. Six chlorinated parabens and their primary degradation products, two chlorinated hydroxybenzoic acids, were found for the first time in river water. Moreover, in river water, chlorinated derivatives preferentially partition into the suspended-solid phase.     

《安全生产法》修订需要重点解决的若干问题研究

分析我国《安全生产法》的贯彻实施情况,总结《安全生产法》实施过程中面临的政府安全生产监管机构职责分工调整、各级安全生产监管部门职责不清和运行不畅、新型的责任保险出现、企业安全生产主体责任不能完全落实等新形势和挑战。为适应我国快速发展的社会环境,以职业安全与健康立法一体化、安全生产监督与管理权限划分、工伤保险与责任保险结合、强化企业安全生产主体责任等难点为重点,提出《安全生产法》相关条款的修订建议、理由和内容。研究结果对完善我国《安全生产法》,提升安全生产法制化水平具有参考意义。     

Effects of parabens on apoptosis induced by serum-free medium

Alkyl esters of p-hydroxybenzoic acids (parabens), an endocrine disrupter, are used as preservatives in cosmetics and foods. In this study, to understand the relationship between parabens and differentiation in infants, the effects of parabens on apoptosis induced by serum deprivation in PC12 cells were investigated. In addition, apoptosis-related factors were assayed. As results, a tendency toward enhancement of apoptosis was observed in the cells cultured in the serum-free medium with methylparaben, and this tendency was suggested to be related to the contents of BAD, a pro-apoptotic protein. Butylparaben did not show any tendency to enhance apoptosis.     

Mercury volatilization by the most mercury-resistant bacteria from the seawater of Minamata Bay in various physiological conditions

The volatilization of mercuric chloride (HgCl₂) and methyl mercuric chloride (CH₃HgCl) by the 45 strains (35 Pseudoalteromonas sp., 2 Vibrio sp., 1 Aeromonas sp., and 7 unclassified) of the most mercury-resistant bacteria from Minamata Bay seawater was examined in various physiological conditions. The bacteria could grow and volatilize HgCl₂ in the liquid medium containing 1-10% NaCl. Two Pseudoalteromonas strains could grow and volatilize HgCl₂ at pH levels ranging from 5.0 to 10.0. The resting cells of 43 strains could volatilize HgCl₂ at concentrations ranging from 30 to 68% after 1-h incubation at 30vv°C. The resting cells of 41 strains could volatilize CH₃HgCl at concentrations ranging from 13 to 88% after 1-h incubation at 30vv°C. Ninety-two percent of mercury was removed from the phosphate buffer containing 0.1 7g/ml by a resting cell of Pseudoalteromonas strain H-4 after 30-min incubation at 30vv°C. We were able to screen the special bacteria, which could volatilize mercury compounds at a high rate in various physiological conditions, for the purpose of developing mercury removal methods using bacteria.