污水生物处理系统细菌衰减特征的实验研究

通过衰减速率测定实验和LIVE/DEAD细胞活性染色实验,分析了污水生物处理系统中细菌在好氧环境下的衰减状态.研究发现,细菌的衰减实质上是由生物量减少引起的数量衰减和由细胞活性降低引起的活性衰减两部分构成的.结果表明,硝化系统细菌在衰减过程中由细胞活性降低引起的衰减约占60%,由细胞死亡引起的衰减约占40%;而在异养系统中由活性降低引起的衰减和由细胞死亡引起的衰减分别为80%和20%.     

我国工伤事故死亡率分析及其ARIMA预测

对我国工伤事故死亡率的历史数据进行分析,介绍ARIMA模型预测法。根据统计学理论,运用ARIMA模型,借助相关软件预测我国工伤事故死亡率,可知未来几年,工伤事故的千人死亡率总体上呈逐年下降的趋势;与移动平均法、指数平滑法预测结果作比较,可知ARIMA模型预测效果最佳;同时,由于影响工伤事故的因素很多,与长期预测相比,ARIMA模型更适合于对工伤事故死亡率作短期预测。     

Photocatalytic activity of ZnO films with micro-grid structure

A layer of zinc oxide (ZnO) micro-grid was deposited on the surface of ZnO film using the DC reactive magnetron sputtering method and the micro-sphere lithography technique on glass substrates. Samples of this layer were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and ultraviolet-visible light spectroscopy. X-ray diffraction showed the high crystallinity of ZnO film and the regular arrangement of the micro-grid. The microgrid ZnO has a lower specular reflection and a higher diffuse reflection, allowing incident light to reflect two or three times to enhance the usage of light. Photocatalytic degradation experiments on methylene blue using both ZnO micro-grid and ordinary film showed that the ZnO micro-grid has better photo-catalytic properties than ordinary film. The ZnO micro-grid enhanced the photocatalytic efficiency of ZnO film by 28% with a degradation time of 300 min.     

2014—2018年某铁路企业职工死亡特征分析

分析某铁路企业职工死因构成和顺位情况,为制定工作场所健康促进策略提供依据。收集20142018年某铁路企业职工死因监测资料和人口数据,按照国际疾病分类标准(ICD-10)进行死因编码,计算死亡率、死因构成指标,进行统计分析。结果表明,20142018年该铁路企业职工年均死亡率为190.22/10万;男性、女性年均死亡率分别为214.56/10万、60.49/10万,男性死亡率高于女性(χ^2=74.83,P<0.001);死因前5位依次为恶性肿瘤、心脏病、脑血管病、伤害和中毒、呼吸系统疾病。进而结合该企业职工死亡以恶性肿瘤居首、心脑血管疾病次之,男性死亡率高于女性,死亡职工绝大多数发生在40~60岁之间等特征,提出制定针对不同人群的综合性防治措施、开展健康管理与健康促进是治本之策。     

A Simple Intervention to Reduce Framing Effects in Perceptions of Global Climate Change

This paper explores a technique for mitigating framing effects in perceptions of global climate change. People's opinions on issues ranging from same sex marriage and the environment to free speech and health care have been shown to be influenced by the way in which the issue is presented: the metaphors, images, and catchphrases that communicate implicit normative messages about the issue. The work described here synthesizes insights from experimental research on moderators of framing effects and sociological research on frame reflection. Based on this synthesis, this paper describes a test of a simple highlighting technique for focusing respondents' attention on the framing operating in political materials. Results suggest that this intervention not only can reduce the opinion-shaping impact of frames but may also reduce ideological polarization. Implications include a better understanding of the mechanisms by which frames operate, techniques for making frame reflection possible among political non-elites, and recommendations for strengthening environmental groups' public communication strategies.     

湿害处理对不同生育时期芝麻叶片保护酶活性和种子产量的影响

对蕾期、盛花期和终花期的芝麻品种进行了24～60 h的湿害处理.测定了叶片保护酶(POD、SOD、CAT)、植株萎蔫率、死株率等14个性状.结果表明,蕾期和盛花期芝麻叶片中保护酶SOD、POD和CAT活性随着湿害处理时间的延长均呈先升后降的趋势,品种间存在差异.蕾期和盛仡期湿害处理对芝麻生长速率、植株萎蔫率和死株牢影响较大,尤以盛花期最为严重.3个生育时期的芝麻品种受湿害处理后均蒴果数减少、种子产量降低、根系早衰甚至烂根.芝麻叶片保护酶活性与植株萎蔫率、死株率旱显著或极显著负相关,与生长速率、有效蒴果数等9个考察性状呈正相关,且大部分相关系数达到显著或极显著水平.综合各项考察指标,湿害处理对芝麻盛花期影响最为严重,K36 h是多项指标发生急剧变化或转折的敏感时间,湿害后的表现型性状变化趋势与叶片保护酶活性变化趋势在品种间基本一致.图4表1参23     

矿井主运输巷道供风管突然垮塌所引发的一起伤亡事故分析

对某矿山所发生的一起矿井主运输巷道供风管突然垮塌所引发的伤亡事故进行了分析,说明了工程质量与安全管理的关系.指出在矿山建设中,一定要重视质量管理.     

Overview of deaths associated with natural events, United States, 1979–2004

Analysis of the National Center for Health Statistics' Compressed Mortality File showed that between 1979 and 2004, natural events caused 21,491 deaths in the United States. During this 26-year period, there were 10,827 cold-related deaths and 5,279 heat-related deaths. Extreme cold or heat accounted for 75 per cent of the total number of deaths attributed to natural events— more than all of deaths resulting from lightning, storms and foods, and earth movements, such as earthquakes and landslides. Cold-related death rates were highest in the states of Alaska, Montana, New Mexico, and South Dakota, while heat-related deaths were highest in the states of Arizona, Missouri, and Arkansas. These deaths occurred more often among the elderly and black men. Other deaths were attributed to lightning (1,906), storms and foods (2,741), and earth movements (738). Most deaths associated with natural events are preventable and society can take action to decrease the morbidity and mortality connected with them.     

聚类分析法在行业事故风险分级中的应用

对聚类分析进行概括,通过对近几年各行业万人重伤率和万人死亡率为指标进行聚类分析,并依据行业的不同对事故进行风险分级,按行业风险大小由低到高分成10级。风险分级结果显示:采掘业的风险等级始终是最高的,其次是电力、煤气及水的生成和供应业,而教育文化艺术及广电业、农林牧渔业、金融保险业、国家机关政党机关和社会团体和卫生、体育和社会福利业的伤亡事故风险等级相对是最低的。该分级结果可以为安全生产管理部门和保险部门提供决策的依据。