结构滞回阻尼比计算方法的改进研究∗

目前计算结构滞回阻尼比常用的方法是能量比法，该方法在给定滞回模型的基础上采用滞回耗能与结构总弹性应变能的比值求得结构滞回阻尼比，但该方法是建立在简谐激励下结构稳态响应的基础之上，对于真实地震下结构滞回阻尼比计算并不完全适用。考虑到这一不足，本文提出一种新的迭代计算结构滞回阻尼比的方法，在Carlos提出的结构滞回阻尼比计算方法的基础上，考虑地震激励频率对阻尼比的影响，通过改进Carlos迭代计算方法，得到了考虑地震激励频率影响的滞回阻尼比计算公式，通过该公式分析得出了不同延性系数和周期比对滞回阻尼比的影响规律，结果表明不同延性系数的结构滞回阻尼比会随着周期比的增大先增大再减小。本研究可为结构进入非线性状态后减震结构总体阻尼比的计算提供理论依据。     

磨细粉煤灰自动装车除尘系统的研制

针对磨细粉煤灰由储料仓向罐式汽车内装料的作业特点,研制了自动化装车除尘系统,解决了装车过程中的粉尘污染问题,并实现了装车过程的自动化。     

淀山湖浮游植物叶绿素a粒径组成及其与水质因子相关性

于2005年6月至2006年5月对淀山湖小型（20～200 μm）、微型（2～20 μm）和微微型（<2 μm）浮游植物叶绿素a和水质因子进行逐月调查研究。结果表明：小型和微型浮游植物是淀山湖水体年均叶绿素a的主要贡献者，二者贡献率之和为7479%。淀山湖叶绿素a粒径组成百分比的季节变动与水体浮游植物群落结构季节演替密切相关：小型浮游植物叶绿素a浓度所占百分比春季最高，而微型、微微型的则分别在秋、冬季最高。相关性分析显示，小型、微型浮游植物叶绿素a浓度百分比与NH3 N含量分别呈显著正、负相关，微微型浮游植物叶绿素a百分比与BOD5呈极显著负相关。对应滤食性鱼类等水生动物的食性粒级，探讨了运用非经典生物操纵技术防治淀山湖富营养化的可行性。〖     

孑遗植物四合木(Tetraenamongolica)迁地保护中的光合作用日变化特征与生理生态适应性

为了进一步廓清迁地保护条件下孑遗植物四合木（Tetraena mongolica）的光合生理生态适应性,在分析了瞬时光合效率的基础上,应用LI-6400光合作用测定系统测定了迁地保护试验区的四合木以及原生境伴生种白刺（Nitraria tangutorum）的光合作用日变化,并测定了其生长量。结果表明：四合木实生苗的生长南北冠幅大小依次为乌海四合木核心区实生苗（26.48 cm×27.26 cm）>鄂尔多斯实生苗（21.27 cm×21.75 cm）>阿拉善实生苗（19.25 cm×18.27 cm）。在原生境地乌海四合木核心区种植的实生苗与阿拉善实生苗之间的生长量存在显著差异（P≤0.01）,与鄂尔多斯实生苗之间的生长量存在显著差异（P≤0.05）。迁地保护条件下四合木生实生苗植株叶片光合速率Pn日变化均呈“双峰”曲线。不同试验区四合木光合作用日变化（Pn）、蒸腾速率（Tr）、气孔导度（Gs）和胞间 CO2浓度（Ci）均表现出明显的分异。迁地保护四合木条件下原生境地栽培的四合木实生苗的光合速率>鄂尔多斯栽培的四合木实生苗的光合速率>阿拉善栽培的四合木实生苗。鉴此可以作进一步推论,孑遗濒危植物四合木从原生境地西鄂尔多斯核心区（乌海）东移进行迁地保护具有更高的生理生态适应性和生境适宜性。但完成“从种子到种子”进而实现“保存性和代表性”,最终实现四合木迁地保护的“保持性和防止性”,保持其遗传多样性和遗传稳定性,最终成功实现四合木的迁地保护仍有待作进一步探索和深入研究。     

Pollution levels and characteristics of phthalate esters in indoor air of offices

The pollution status and characteristics of PAEs (phthalate esters) were investigated in indoor air of offices, and PAEs of both gas-phase and particulate-phase were detected in all the samples. The concentration (sum of the gas phase and the particulate phase) was 4748.24 ng/m³, ranging between 3070.09 and 6700.14 ng/m³. Diethyl phthalate, dibutyl phthalate, and di(2-ethylhexyl) phthalate were the most abundant compounds, together accounting for 70% of the Σ6PAEs. Dividing the particulate-phase PAEs into four size ranges (<2.5, 2.5-5, 5-10, >10 μm), the result indicated that PAEs in PM_2.5 were the most abundant, with the proportion of 72.64%. In addition, the PAE concentration in PM_2.5 correlated significantly with the total particulate-phase PAEs (R² = 0.85). Thus, the amount of PAEs in PM_2.5 can be estimated from the total amount of particulate-phase PAEs using this proportion. In a comparison between the offices and a newly decorated study room, it was found that pollution characteristics were similar between these two places. Thus, it is implied that the PAE concentration decreased by 50% 2 yr after decorating.     

Pollution levels and characteristics of phthalate esters in indoor air of offices

The pollution status and characteristics of PAEs(phthalate esters) were investigated in indoor air of offices, and PAEs of both gas-phase and particulate-phase were detected in all the samples. The concentration(sum of the gas phase and the particulate phase) was4748.24 ng/m3, ranging between 3070.09 and 6700.14 ng/m3. Diethyl phthalate, dibutyl phthalate, and di(2-ethylhexyl) phthalate were the most abundant compounds, together accounting for 70% of the ∑ 6PAEs. Dividing the particulate-phase PAEs into four size ranges( 2.5, 2.5–5, 5–10, 10 μm), the result indicated that PAEs in PM2.5were the most abundant,with the proportion of 72.64%. In addition, the PAE concentration in PM2.5correlated significantly with the total particulate-phase PAEs(R2= 0.85). Thus, the amount of PAEs in PM2.5can be estimated from the total amount of particulate-phase PAEs using this proportion. In a comparison between the offices and a newly decorated study room, it was found that pollution characteristics were similar between these two places. Thus, it is implied that the PAE concentration decreased by 50% 2 yr after decorating.     

Pollution levels and characteristics of phthalate esters in indoor air in hospitals

The concentrations of phthalate esters(PAEs) in Chinese hospitals were investigated by simultaneously determining concentrations of gas- and particle-phase PAEs. PAEs were detected in two third-class first-grade hospitals, two second-class first-grade hospitals, and a community health service center. Hospital drugstores had the highest concentration(24.19 μg/m3), which was 1.54 times that of newly decorated houses. The second highest concentration was found in the transfusion rooms, averaging 21.89 μg/m3; this was followed by the concentrations of PAEs in the nurse's workstations, the wards, and the doctor's offices, with mean concentrations of 20.66, 20.0, and 16.92 μg/m3, respectively. The lowest concentrations were found in the hallways(16.30 μg/m3). Of the six different kinds of PAEs found, major pollutants included diethyl phthalates, dibutyl phthalates, butylbenzyl phthalates and di(2-ethylhexyl) phthalates, comprising more than 80% of all PAEs present.Meanwhile, a comparison between different wards showed that PAE concentrations in the maternity wards were 1.63 times higher than in the main wards. Based on known health hazards, our results suggest that the PAEs seriously influence the health of the pregnant women and babies; therefore, it is of great importance to take the phthalate concentrations in hospitals into consideration. In addition, hospital indoor air was more seriously contaminated than the air of newly decorated houses.     

运动对急性暴露于2,3,7,8-四氯二苯并二恶英大鼠肝组织酶活性的影响

为了研究运动对2,3,7,8-四氯二苯并二恶英(2,3,7,8-TCDD)急性暴露大鼠肝组织酶活性的影响,将40只雄性Wistar大鼠随机分为正常对照组(NC)、染毒组(NT)、运动对照组(EC)、运动染毒组(ET)。染毒组(NT组与ET组)腹腔注射10μg·kg-1(以单位体重计)的TCDD,对照组(NC组与EC组)腹腔注射等量的玉米油;NT、NC组静养4周,ET、EC组运动(尾部负重5%游泳30分钟)4周。4周后,称重并宰杀大鼠,分离肝组织,称重后-80℃保存待测7-乙氧基异吩恶唑酮脱乙基酶(EROD)、7-乙氧基香豆素-O-脱乙基酶(ECOD)及芳香烃羟化酶(AHH)的活性。将数据进行多因素方差分析(MAVONA)处理,结果表明,染毒可降低大鼠体重,增加肝湿重和肝相对重量、增加EROD、ECOD活性;运动可增加大鼠肝相对重量、增加AHH的活性;染毒后运动可降低EROD、ECOD的活性。结论:急性10μg·kg-1(以单位体重计)TCDD染毒后4周可增加大鼠肝相对重量;4周的运动能有效降低TCDD对EROD、ECOD活性的激活作用。