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1.
目的:了解石油管道储运员工的心理健康现状,建立管道储运员工症状自评量表(SCL-90)的群体常模。方法:运用整群抽样方法和症状自评量表(SCL-90)对5544名中国石化管道储运公司员工进行心理健康状况调查,将SCL-90结果与中国常模比较。结果:本次调查心理健康状况好3947人,占71.2%;心理健康状况良好1299人,占23.4%;心理健康状况一般238人,占4.3%;心理健康状况异常60人,占1.1%;石化管道储运员工在躯体化、焦虑、精神病性、阳性项目数均分显著高于全国常模;人际关系、敌对、偏执和精神病性因子均分男性显著高于女性,恐怖因子均分女性显著高于男性;35岁及以上组的躯体化、强迫、抑郁、焦虑、敌对、恐怖、精神病性以及阳性项目数的因子均分均高于35岁以下组;大专组和高中及以下组各项因子均分均显著高于本科及以上组。结论:管道储运员工心理健康状况低于一般人群。年龄相对较大以及学历相对较低员工的心理健康状况是企业关注的重点。  相似文献   
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Parks with various types of vegetations played an important role in ameliorating air quality in urban areas. However, the attenuation effect of urban vegetation on levels of air pollution was rarely been experimentally estimated. This study, using seasonal monitoring data of total suspended particles (TSP), sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2)) from six parks in Pudong District, Shanghai, China, demonstrated vegetations in parks can remove large amount of airborne pollutants. In addition, crown volume coverage (CVC) was introduced to characterize vegetation conditions in parks and a mixed-effects model indicated that CVC and the pollution diffusion distance were key predictors influencing pollutants removal rate. Therefore, it could be estimated by regression analysis that in summer, urban vegetations in Pudong District could contribute to 9.1% of TSP removal, 5.3% of SO(2) and 2.6% of NO(2). The results could be considered for a better park planning and improving air quality.  相似文献   
4.
我最早的一张照片是站在母亲身旁照的。母亲抱着四弟,我穿着有褶皱的棉袍,一只袖口露着镯子,一只手搭在母亲的腿上,面部表情凝重而又满足,显得对母亲十分依恋。母亲穿着带有暗花的夹袍,留着披肩长发,面带微笑。幼年的我,脸庞十分像母亲。这张照片应拍摄于1944年早春,当时我三岁多。  相似文献   
5.
为深入研究极近距离煤层综放开采工作面覆岩“两带”的动态发育规律,采用理论推导、数值模拟和现场实测相结合的方法,分析袁店一矿824工作面覆岩“两带”的裂隙演化特征。结果表明:从岩层层向拉伸率角度,研究上覆岩层垮落带和导水裂隙带的垮落程度,考虑角度影响推导出岩层弯曲下沉边缘段变形前后的长度计算公式,根据覆岩的碎胀特征计算各岩层的最大下沉量,预测垮落带和裂隙带的范围分别为30.2~41.2 m和70.7~78.2 m;采用3DEC数值模拟分析该矿824工作面开挖后上覆岩层垮落的基本形态和裂隙分布规律,结合其应力、位移云图和监测线位移曲线的分布特征,得出垮落带和裂隙带的高度分别为32.50 m和77.25 m;采用分布式光纤应变监测系统,监测工作面前方80 m处上部顶板的受力情况,得出受采动影响的光纤应变呈起伏变化,且应变分布与地层岩性存在对应关系,得出垮落带高度约30.4 m,裂隙带高度约74.8 m,验证采用层向拉伸率和覆岩碎胀性2个方面来预测工作面覆岩“两带”高度的合理性,可为类似方面的研究与施工提供相应的技术依据。  相似文献   
6.
The vulnerability of forest ecosystem services to climate change is expected to depend on landscape characteristic and management history, but may also be influenced by the proximity to the southern range limit of constituent tree species. In the Western Rhodopes in South Bulgaria, Norway spruce is an important commercial species, but is approaching its current southern limit. Using climate sensitive forest models, we projected the impact of climate change on timber production, carbon storage, biodiversity and soil retention in two representative landscapes in the Western Rhodopes; a lower elevation landscape (1000–1450 m a.s.l) dominated by mixed species forests, and a higher elevation landscape (1550–2100 m a.s.l.) currently dominated by spruce. In both landscapes climate change is projected to induce a shift in forest composition, with drought-sensitive species, such as Norway spruce, being replaced by more drought-tolerant species such as Scots pine and black pine at lower elevations. In the higher elevation landscape a reduction in spruce growth is projected, particularly under the more severe climate change scenarios. Under most climate scenarios a reduction in growing stock is projected to occur, but under some scenarios a moderate increase in higher elevation stands (>1500 m a.s.l.) is expected. Climate change is projected to negatively influence carbon storage potential across landscapes with the magnitude depending on the severity of the climate change scenario. The impact of climate change on forest diversity and habitat availability is projected to differ considerably between the two landscapes, with diversity and habitat quality generally increasing at higher elevations, and being reduced at lower elevations. Our results suggest that if currently management practices are maintained the sensitivity of forests and forest ecosystem services in the Western Rhodopes to climate change will differ between low and higher elevation sites and will depend strongly on current forest composition.  相似文献   
7.
表土植硅体组合与其上覆植被类型之间的关系研究是利用植硅体进行古气候和古植被重建的基础.选取位于湿润亚热带地区的戴云山作为研究对象,沿海拔梯度以50?—?100 m为间隔共采集21个表土样品,以探讨该地区表土植硅体组合对山地植被的指示意义.结果表明:戴云山表土植硅体含量丰富,类型多样,主要以禾本科类植硅体占优势;此外,随着海拔的升高,表土植硅体组合中哑铃型和短鞍型百分含量快速增加,而扇型和长鞍型,特别是木本类植硅体的百分含量则逐渐减少,指示了山地植被从温性针叶林向常绿灌丛林的过渡,说明戴云山表土植硅体组合能够反映山地垂直植被带变化的主要特征;植硅体类型主成分分析(PCA)结果显示位于湿润亚热带地区的戴云山表土植硅体组合变化可能主要受温度的控制.本研究为今后在湿润亚热带山地地区开展古气候和古植被重建研究提供了重要的基础资料.  相似文献   
8.
Fang GC  Chang CN  Wu YS  Wang NP  Wang V  Fu PP  Yang DG  Che SC 《Chemosphere》2000,41(9):1349-1359
Aerosol samples for PM2.5, PM(2.5-10) and TSP were collected from June to September 1998 and from February to March 1999 in central Taiwan. Ion chromatography was used to analyze the acidic anions: sulfate, nitrate and chloride in the Universal samples. The ratios of fine particle concentrations to coarse particle concentrations displayed that the fine particle concentrations are almost greater than that of coarse particle concentrations in Taichung area. The average concentrations of PM2.5, PM(2.5-10) and TSP in urban sites are higher than in suburban and rural sites at both daytime and night-time. Chloride dominated in the coarse mode in daytime and in fine mode in night-time. Nitrate can be found in both the coarse and fine modes. Sulfate dominated in fine mode in both daytime and night-time.  相似文献   
9.
针对实际海水养殖废水低碳高氮的特点,采用间歇式活性污泥法(SBR)和好氧活性污泥添加硅藻土载体的方式,考察硅藻土载体和活性污泥共同作用下的好氧曝气系统对海水养殖废水中氨态氮(NH4+-N)、亚硝酸态氮(NO2--N)和化学耗氧量(COD)的去除效果,以及对污泥沉降性能和硝化细菌特征的影响。实验结果表明,常温条件下,溶解氧(DO)≥ 4.5 mg/L,pH控制在7.0 ~ 8.0,HRT为11 h,沉降时间10 min,反应器可以处理NH4+-N浓度在50 mg/L左右的海水养殖废水,NH4+-N和COD去除率分别达到98.93%左右和76.62%以上,NO2--N出水浓度低于0.028 mg/L。载体污泥颗粒照片和扫描电镜结果表明,添加硅藻土载体内核后,颗粒污泥的成熟期缩短,颗粒的稳固度和沉降性能提高。在系统启动成功稳定运行后,通过FISH分析表明,在氨氧化菌(AOB)与亚硝酸盐氧化菌(NOB)成为优势菌群后,AOB大约占总菌群的33.5%,并且AOB与NOB菌群数量约为1:1.33,AOB和NOB两大类菌群之和约占总菌群的77.2%,成为系统中优势菌群。  相似文献   
10.
This study examines people's immediate responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch and 332 respondents in Hitachi revealed notable similarities between the two cities in people's emotional reactions, risk perceptions, and immediate protective actions during the events. Respondents' physical, household, and social contexts were quite similar, but Hitachi residents reported somewhat higher levels of emotional reaction and risk perception than did Christchurch residents. Contrary to the recommendations of emergency officials, the most frequent response of residents in both cities was to freeze. Christchurch residents were more likely than Hitachi residents to drop to the ground and take cover, whereas Hitachi residents were more likely than Christchurch residents to evacuate immediately the building in which they were situated. There were relatively small correlations between immediate behavioural responses and demographic characteristics, earthquake experience, and physical, social, or household context.  相似文献   
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