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1.
Yu-mei Wei Wei-li Tian Qing-yu Zhang Ying-yue Zheng Yi-ke Yang Zu-cheng Wu Qi Zhu Lei Zhou Si-mai Fang 《浙江大学学报(A卷英文版)》2011,12(10):794-806
Population exposure to pollutants is important for studies on the exposure-response relationship. However, it is difficult
to evaluate population exposure to non-conventional pollutants due to limited data on concentration levels and the movement
patterns of inhabitants. In this study, an air dispersion model was used to simulate N, N-dimethylformamide (DMF) concentrations,
as a proxy to monitoring concentrations. A total of 1289 randomly selected household representatives were surveyed to obtain
information on movement characteristics. Subsequently, population movement patterns were combined with DMF concentration levels
on maps of 100 m×100 m resolution to calculate population exposure. During 2008, the estimated population exposure to DMF
ranged from 0.002 to 0.64 mg/m3. The highest level of population exposure to DMF was found in the north and northwest sub-districts of the study area, ranging
from 0.42 to 0.64 mg/m3. The population exposure to DMF for different occupational groups indicated that retired people and farmers were vulnerable
subpopulations among people highly exposed to DMF. This was mainly because they spent most time at home where the DMF concentration
was high. As pollutant concentrations were divided into small grids, we found that exposure levels were substantially impacted
by population movement characteristics. 相似文献
2.
Jun-chun ZHANG Le-ming CHENG Cheng-hang ZHENG Zhong-yang LUO Ming-jiang NI 《浙江大学学报(A卷英文版)》2013,14(9):671-678
In this study, a porous inserted regenerative thermal oxidizer （PRTO） system was developed for a 125 kW industrial copper-melting furnace, due to its advantages of low NOr emissions and high radiant efficiency. Zirconium dioxide （ZrOz） ce- ramic foams were placed into the combustion zone of a regenerative thermal oxidizer （RTO）. Different performance characteris- tics of the RTO and PRTO systems, including pressure drop, temperature distribution, emissions, and energy efficiency, were evaluated to study the effects of the porous inserts on non-premixed CH4 combustion. It was found that the PRTO system achieved a significant reduction in the NOx emission level and a fuel saving of approximately 30% compared to the RTO system. It is most suitable for a lean combustion process at an equivalence ratio 〈0.4 with NOx and CO emission levels within 0.002%~）.003% and 0.001%q3.002%, respectively. 相似文献
3.
南京市经济增长与环境污染关系的研究 总被引：2，自引：0，他引：2
李金莲 《南京晓庄学院学报》2010,26(6):102-107
文章根据1985～2007年南京统计年鉴的有关数据,选取工业三废中的废水排放量、废气中的SO2排放量、烟尘排放量、固体废物产生量、工业粉尘排放量等指标,构造环境污染与人均GDP之间的计量经济模型,并分析研究它们之间的关系.研究结果表明：南京市废水排放量、SO2排放量、烟尘排放量、工业粉尘排放量等环境指标均符合环境库兹涅茨曲线特征,其拐点对应的人均GDP依次为4464、10189、9007和12844元（1990年价格）,发生转折的年份分别为1992、1995、1994、1996年;工业固体废物排放量还没有出现拐点,其排放量仍在持续增加.产业结构调整、环保投资和强有力的环境管理是推动南京市在较低的人均GDP跨越环境库兹涅茨曲线拐点的重要驱动因子,南京市今后只有进一步完善目前的环境保护政策,加大环境保护工作的力度,才可能最终实现生态环境质量的全面改善. 相似文献
4.
三台县城区大气环境质量分析与评价 总被引：1，自引：0，他引：1
根据2006～2007年三台县城区SO2、NO2、PM10浓度的监测数据,综合运用大气环境质量指数评价法和污染负荷分析法对三台县城区的大气质量进行分析与评价。结果表明：三台县城区主要大气污染物依次为PM10、SO2和NO2,污染程度相对较低,2007年较之2006年大气质量总体上有较大改善。SO2和PM10在2006～2007年间污染负荷均呈下降趋势,而NO2则呈现上升趋势,说明三台县城区大气污染正由煤烟型逐步向燃气型的趋势过渡。 相似文献
5.
在过去的40年里,广东省花都区狮岭皮具专业镇借助我国改革开放政策的大潮实现了产业的快速发展。狮岭皮具专业镇的健康发展对于拉动地方经济发展、优化地方经济结构、推动地方产业转型升级发挥着极为重要的作用。皮具工匠人才培养分级指标的设定,对扭转当前皮具工匠人才供给不足的现状、促进皮具工匠职业化成长和满足狮岭皮具专业镇产业升级的实际需求都具有重要意义。通过对皮具工匠人才分级指标要素的分析,探究出一系列推动皮具人才分级指标实施路径,包括工匠精神在工匠人才分级体系的渗透、现代学徒制在皮具工匠人才分级指标体系的实现、皮具专业镇产业结构深化调整、皮具专业镇特色产业集群做大做强、分级指标培养体系引导人力资源聚集等,从而实现广东省皮具工匠人才专业素养的提升,促进皮具专业镇的可持续发展。 相似文献
6.
2007年10至2008年3月,笔者利用定点观测法对半边湖的鸟类资源再次进行了监测。调查到国家一级保护鸟类2种：东方白鹳和白鹤;国家二级保护鸟类三种：小天鹅、灰鹤、普通狂;其它鸟类6种,共计11种956只。对比2006年10月至2007年2月的调查结果发现：三峡大量蓄洪、滥种速生杨、滥捕鱼虾等因素是半边湖珍稀鸟类减少的主要原因。 相似文献
7.
Pamela Lockwood Emily Hunt Ray Matlack Judy Kelley 《Community College Journal of Research & Practice》2013,37(8):613-619
Increasing Numbers, Connections, and Retention in Science and Engineering (INCRSE) was funded with the goal of increasing the quantity, quality, and diversity of undergraduate students pursuing and obtaining degrees in Science, Technology, Engineering, and Mathematics (STEM) programs at West Texas A&M University (WTAMU). A major objective of INCRSE was to recruit STEM transfer students from regional community colleges (CC) and to provide academic and social support necessary for retention of these students. The INCRSE CC recruitment and retention model involved (a) strengthening relationships between faculty at WTAMU and regional CCs; (b) inviting CC faculty and staff to developmental workshops at WTAMU; (c) improving advising for transfer students at CCs and WTAMU; and (d) developing articulation agreements between WTAMU and regional CCs. Because INCRSE was funded in fall 2006, the number of CC STEM transfers enrolled at WTAMU increased from 214 to 253, an increase of 18%, while overall enrollment of CC transfers to WTAMU declined 3.5%. The number of new CC STEM transfers increased 22% from 92 in the 2006–2007 to 112 in 2008–2009 academic years. WTAMU's first-year retention of STEM transfers increased from 57% in 2006–2007 to 68% in 2007–2008, far surpassing the WTAMU first-year retention of traditional freshmen in the STEM fields by almost 30%. While all components of the model were important, much of the success can be attributed to improved relationships between WTAMU and CC faculty. 相似文献
8.
张淑娟 《中山大学学报论丛》1990,(1)
通过调查汕头龙湖片大气污染物:SO_2、NO_x、总悬浮微粒(TSP)和降尘的合量,研究它们在不同功能区的浓度分布、日变化和冬、夏季变化规律,从而评价该地区的大气环境质量,为特区大气环境保护提供科学依据。 相似文献
9.
Conclusions In spite of very high toxic potency of PAH, in India environmental monitoring and assessment of PAH is rarely done compared
to European countries and US. The Central Pollution Control Board (CPCB) had recently initiated regular monitoring of PAHs
in ambient air in select cities. According to CPCB, ambient air PAH in Delhi ranged between 9.4–60.9 nanograms per cubic meter
(ng/m3) during 1999–2000 with higher values recorded in winter. Other research studies reported about 4.999.56 ng/m3 of benzo[a]pyrene in suspended paniculate matter (SPM) during 1986 in urban Delhi. In Calcutta, sum of 12 PAHs was 22.91 and 190.96
ng/m3 in SPM at Jadavpur and Maulali respectively, in 1994. The average benzo[a]pyrene concentration was 10.4+4.76 ng/m3. These levels are apparently manifold higher than the European standards. Apart from few such studies no detailed studies
are available in India. Even in the current standards and specifications for diesel engines there is no emission limit for
PAH. Recently it had specified that 10% of PAH by hydrocarbons as limit that should be adopted by 2005.
In the current Indian scenario, especially after the economic liberalization in 1991, the motor vehicle population is increasing
rapidly, leading to corresponding increase in PAH emissions. The role of PAHs in cardiovascular mortality, cancer cases and
several other health abnormalities that are reported nowadays cannot be ignored. 相似文献
10.
By the application of life cycle assessment（LCA） methodology, this paper estimates the environmental impacts of production and disposal of traction motors used in electric vehicles in China. The results show that the total energy use, the criteria emissions and the greenhouse gases（GHG） emissions of a traction motor production and disposal are about 2,899,MJ, 4.5,kg and 259.5,kg per motor, respectively. Among the regulated emissions, the SOxemission ranks first by total mass, followed by CO, PM10, NOx, PM2.5, and volatile organic compound（VOC）. The motor material production stage accounts for most of the energy consumption and emissions, followed by the assembly stage and the end-of-life disposal stage. In this study, the environmental performance analysis is extended to the comparison between the use of secondary material and primary material for the material production stage. It is found that using 100% secondary material results in a 52.9% reduction in energy consumption, a 49.8% reduction in regulated emissions, and a 49.3% reduction in GHG emissions compared with the use of 100% primary material. 相似文献
11.
以皮革下脚料铬革屑经碱法制得的蛋白粉为复合氨基酸来源.对饲料添加剂复合氨基酸铜螯合物的合成工艺条件进行了初步的探讨.主要研究了PH值、温度、时间对螯合反应的影响.确定了合适的螯合反应条件:pH=11.0,温度为60℃,时间为30min.并在该条件下测得反应的最佳质量比为mCuSO4·5H2O:mAA=1:3;配位比为nCu2 :nAA=1:2;产品螯合率达到93%.并用红外光谱法鉴定产物. 相似文献
12.
Characteristics and sources of polycyclic aromatic hydrocarbons in impervious surface run-off in an urban area in Shanghai, China 总被引：1，自引：0，他引：1
Rainwater and run-off from three kinds of impervious surface in the Shanghai urban area, China were sampled. Polycyclic aromatic hydrocarbons （PAHs） were measured in the samples, and their sources were assessed. The mean sum of the 16 PAH concentrations measured in rainwater and run-offs from ceramic tiles, asphalt roofs, and asphalt roads were 873, 1404, 1743, and 4023 ng/L, respectively. The PAH concentrations found in this study were moderate compared to PAH concentrations found in run-offs in other studies. The main PAH components in the rainwater, roof run-off, and asphalt road run-off samples were 3-ring PAHs, 3-4-ring PAHs, and 4~6-ring PAHs, respectively. Source apportionment results indicated that combustion （47.4%-55.5%） and vehicular emissions （30.5%-33.0%） were the major contributors to PAHs in roof run-off. Vehicular emissions were the most significant contributors to asphalt road run-off （47.2%）, followed by combustion （23.5%）, and petroleum （16.3%）. Vehicular emissions and coal and natural gas combustion are therefore the most significant sources of PAHs in run-off from impervious surfaces in the Shanghai urban area. 相似文献
13.
富马酸二甲酯的合成及其市场开发前景 总被引：4，自引：0，他引：4
高翠英 《吕梁高等专科学校学报》2007,23(1):9-11
富马酸二甲酯是一种新型的杀菌剂.根据国内外的研究报道,对其合成、性质和应用等方面的研究进展,表明开发生产富马酸二甲酯具有广阔的市场开发前景. 相似文献
14.
中国学前教育研究会立项课题的研究状况与分析 总被引：1，自引：1，他引：0
本文采用内容分析法,对“十五”（2001-2005）、“十一五”（2006—2007）规划时期“中国学前教育研究会立项课题”进行了分析,分析维度涉及课题数量、课题承担人员、课题选题。分析结果表明：“十五”“十一五”期间,中国学前教育研究会立项课题共549项;课题承担者主体为幼儿园,共323项,占课题总数的59．9％;课题负责人所在单位主要位于沿海城市等发达地区或具有重视学前教育传统的地区;课题选题丰富,不同单位的承担者在课题选题方面存在极其显著的差异。 相似文献
15.
DMF与CHCl_3混合液精馏分离工艺的研究 总被引：1，自引：0，他引：1
采用模拟的二甲基甲酰胺(DMF)与三氯甲烷(CHCl3)混合液(DMF质量分数为47%),通过精馏塔进行分离。当进料量为2L·h-1时,得出最佳的操作条件如下:进料状态为泡点进料,加料位置为第七块塔板进料,回流比为4。最终结果为:理论塔板数为4.5块,塔板效率为37.5%,塔顶产品DMF质量分数低于0.01%,塔底产品DMF质量分数达到96.03%。该新方法与传统的直接精馏法相比既能减少精馏能耗,又能回收利用DMF,还可使萃取剂CHCl3重复使用,对环境友好不造成污染。 相似文献
16.
根据经济周期波动监测预警理论,构建基于神经网络的经济周期波动监测预警模型系统。在此基础上,利用我国2006年经济数据,编制2006年景气预警指标信号图,并利用BP神经网络模型对2007年1月份的预警指标进行仿真预测和预警,仿真结果表明了该方法的有效性和可行性。 相似文献
17.
《The Internet and Higher Education》2010,13(3):108-114
A study by Mullen and Tallent-Runnels (2006) found significance in the differences between online and traditional students' reports of instructors' academic support, instructors' demands, and students' satisfaction. They also recognized that the limitation to their study was their demographic data. In an original report funded by the Alfred P. Sloan Foundation, Dziuban, Hartman, Moskal, Brophy-Ellison, and Shea (2007) identified multiple student satisfaction groupings into dimensions that can provide structure to studies in online learning. In the present study, differences between academic standing and ethnicity were added to broaden the Mullen and Tallent-Runnels (2006) demographic deficiencies and used several student satisfaction dimensions identified by Dziuban, Moskal, Brophy-Ellison, and Shea (2007) and Moskal, Dziuban, and Hartman, (2009). The differences between academic standing and the studied dimensions were found to be statistically significant: the largest effect was Facilitated Learning and academic standing, which accounted for nearly 15% of the student scores' variance; and Engagement and Information Fluency had variance effects of, respectively, 4.5%, and 5.1%. However, error accounts for the majority of total variance in all the tests, which implies other variables' influence. 相似文献
18.
戴德颐 《江苏经贸职业技术学院学报》2020,(1):1-6
基于STIRPAT模型,运用面板回归方法,定量分析东部10省市的产业结构、城市化水平与二氧化碳排放之间的关系。结果表明:不同行业对二氧化碳排放的影响差异显著,其中石油石化类行业对二氧化碳排放的促进作用最明显,而金融业对二氧化碳排放略有降低作用;城市化率提高会促进二氧化碳排放。为尽快形成低能耗、低污染的绿色发展模式,地方政府需要发挥产业政策的引导作用,推广节能减排技术,控制二氧化碳排放量。 相似文献
19.
目的:分析耳鸣与耳蜗毛细胞早期损害的关系,探讨耳鸣的客观检查手段.方法:实验组为40例(66耳)纯音听力正常的耳鸣患者,对照组为40例(80耳)听力正常无耳鸣的正常人,二组均行诱发性耳声发射检查:瞬态耳声发射(TEOAE)和畸变产物耳声发射(DPOAE)检查.结果:1.TEOAE通过率,对照组为100%,实验组为42.4%,两组有显著性差异(P＜0.01);2.DPOAE通过率,对照组为100%,实验组为51.5%,两组有显著性差异(P＜0.01).结论:部分听力正常的耳鸣患者已有耳蜗毛细胞的损害;TEOAE及DPOAE可以作为外周性耳鸣诊断的一种客观检测方法. 相似文献
20.
采用离子色谱电导检测法测定皮革制品中Cr（Ⅳ）,选用Metrohm86I型离子色谱仪,Metrosep A Supp5—150型阴离子分析柱,12．8mmol／LNa2C03＋4．0mmol／LNaHC03淋洗液．在10～100μg／L范围内,Cr（Ⅳ）的浓度与色谱峰面积呈线性关系,线性方程为C×100—2893．72×A＋200．136,相关系数为0．9990,最低检测浓度为4μg／L,低、中、高三个浓度的精密度分别为1．60％、1．05％、0．65％,样品加标回收率分别为91．5％、93．6％和92．3％,本方法可用于皮革中Cr（Ⅵ）的测定． 相似文献