中空夹层钢管混凝土-钢管K形搭接节点抗震性能试验研究

主管为中空夹层钢管混凝土，支管为空钢管的K形搭接节点，按主圆支圆和主方支圆两种形式加工制作了4个节点，对节点两个支管通过同步往复加载，研究主管通过夹层混凝土加强的K形节点破坏模式、承载力、耗能性能等。分析了试件的滞回曲线、骨架曲线、承载力、延性系数、能量耗散系数等抗震性能指标。结果表明：未加强节点的破坏模式为主管表面塑性破坏，主管夹层灌混凝土的加强节点为支管拉裂破坏；主管夹层灌混凝土提高了节点的刚度和承载力，对于方管尤为显著，但对节点的延性影响不大；相比主圆支圆的未加强试件，夹层灌普通混凝土和粉煤灰混凝土的试件承载力分别提高了43.7%和52.1%，节点累积耗能分别提高了57.6%和64.0%；相比主方支圆未加强试件，夹层灌普通混凝土和粉煤灰混凝土的试件承载力分别提高了66.7%和64.7%，节点累积耗能分别提高了39.8%和21.7%，但主管夹层灌普通混凝土和灌粉煤灰混凝土对节点的加强效果区别不大。利用ANSYS软件对试验试件进行有限元分析，分析结果与试验结果吻合良好，并选用主管空心率、支主管直径比及支管径厚比进行参数分析。分析表明：随主管空心率的增大，节点耗能能力和承载力有所减小；随支主管直径比的增大，节点滞回曲线趋于饱满，耗能能力和承载力提高；随支管径厚比的增加，节点的滞回曲线的饱满度降低，节点承载力和耗能能力均呈下降趋势。     

高温相变蓄热电暖器散热功率调节性能试验研究

对笔者研制的高温相变蓄热电暖器风道、散热肋片的强化散热性能及风门对散热量的调节特性进行了试验研究，结果表明风道、散热肋片可显著强化散热，不同风门开度下散热功率差别明显。     

新型混凝土储热材料的研制

研究了在材料中添加热容、热导率大的物质来改善材料整体性能的方法。研究结果表明:当铝酸盐水泥含量为10%时,材料的抗压、抗折强度能满足工业需求;材料的比热容在350℃时达到4.5 kJ/(kg.K),接近甚至超过某些相变储热材料的比热容;随着石墨粉含量的增加,材料的热导率几乎成直线上升,当石墨含量为5%时材料的热导率大于1.7 W/(m.K)。     

Arsenic groundwater contamination and its health effects in the state of Uttar Pradesh (UP) in upper and middle Ganga plain, India: a severe danger

This communication presents results of our 2-year survey on groundwater arsenic contamination in three districts Ballia, Varanasi and Gazipur of Uttar Pradesh (UP) in the upper and middle Ganga plain, India. Analyses of 4,780 tubewell water samples revealed that arsenic concentrations in 46.5% exceeded 10 microg/L, in 26.7%, 50 microg/L and in 10% 300 microg/L limits. Arsenic concentrations up to 3,192 microg//L were observed. The age of tubewells (n=1,881) ranged from less than a year to 32 years, with an average of 6.5 years. Our study shows that older tubewells had a greater chance of contamination. Depth of tubewells (n=3,810) varied from 6 to 60.5 m with a mean of 25.75 m. A detailed study in three administrative units within Ballia district, i.e. block, Gram Panchayet, and village was carried out to assess the magnitude of the contamination. Before our survey the affected villagers were not aware that they were suffering from arsenical toxicity through contaminated drinking water. A preliminary clinical examination in 11 affected villages (10 from Ballia and 1 from Gazipur district) revealed typical arsenical skin lesions ranging from melanosis, keratosis to Bowens (suspected). Out of 989 villagers (691 adults, and 298 children) screened, 137 (19.8%) of the adults and 17 (5.7%) of the children were diagnosed to have typical arsenical skin lesions. Arsenical neuropathy and adverse obstetric outcome were also observed, indicating severity of exposure. The range of arsenic concentrations in hair, nail and urine was 137-10,900, 764-19,700 microg/kg, and 23-4,030 microg/L, respectively. The urine, hair and nail concentrations of arsenic correlated significantly (r=0.76, 0.61, and 0.55, respectively) with drinking water arsenic concentrations. The similarity to previous studies on arsenic contamination in West Bengal, Bihar and Bangladesh indicates that people from a significant part of the surveyed areas in UP are suffering and this will spread unless drives to raise awareness of arsenic toxicity are undertaken and an arsenic safe water supply is immediately introduced.     

高海拔隧道火灾烟气及温度场数值模拟研究

采用FDS 建立典型双车道公路隧道，对海拔高度为500、4 000 m 的公路隧道发生火灾时的烟气蔓延特征及温度分布规律进行数值模拟分析，以得到低压、低温、低氧含量等高海拔环境对公路隧道火灾发展的影响规律。结果表明：相比较平原地区隧道，高海拔地区公路隧道火灾烟气最高温度更低，火焰高度更高，且近火源区的拱顶最高温度升温速度明显大于远火源区；在同等火灾热释放速率下，高海拔地区隧道内烟气一维纵向蔓延长度更大，且近火源区隧道上层高温烟气与下层冷空气界限较为分明，而远火源区则逐渐出现较为明显的烟气下沉现象。     

Community response to environmental noise and the impact on cardiovascular risk score

Objective

The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.

Methods

The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, L_eq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, L_eq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).

Results

Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).

Conclusions

These findings highlight the association between road traffic noise and cardiovascular risk.     

基于Web的工程项目管理信息系统

介绍了基于Web的工程项目管理信息系统的开发目标、设计原则、主要功能和不足之处。本系统是实行现代化管理的一种新的模式,它通过网络和数据库实现信息的及时交流和数据共享,从而为决策提供支持和服务。     

湿式储气罐水槽底板漏水处理方法

对湿式燃气储气罐水槽底板漏水的处理方法进行了比较，介绍了挖掘法的施工方法和效果。     

高压注浆土钉特性及应用

面对重力注浆土钉的一些不足，提出了高压注浆土钉，并对它的一些特性作了一些探讨。通过土钉抗拔力学模型探讨了高压注浆士钉的抗拔荷载传递机理，简单介绍了其施工工艺。从土钉长度、抗拔安全系数、界面粘结强度、抗滑稳定性等方面说明了高压注浆土钉的优越性，并从实例分析证明其可行性。     

水的磁化对结冰的影响初探

通过采用高效多用途磁化器使水磁化,实验研究了磁化对水的最低不结冰温度的影响,发现磁化后水的结冰温度降低1℃左右,有利于提高过冷水蓄能效率、增加蓄冷系统经济效益和节约能源。