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911.
Volatilization behaviors of diesel oil from the soils   总被引:7,自引:1,他引:6  
The volatilization of diesel oil, Shengli crude oil and 90 # gasoline on glass surface of petri dishes were conducted at the ambient temperature of 25℃. Diesel oil evaporates in a power manner, where the loss of mass is approximately power with time. 90 # gasoline evaporates in a logarithmic with time. Where as the volatilization of Shengli crude oil fit either the logarithmic or power equation after different time, and has similar R^2 . And the effects of soil type and diesel oil and water content on volatilization behavior in unsaturated soil were studied in this paper. Diesel oil and water content in the soils play a large role in volatilization from soils. Appropriate water helps the wicking action but too much water stops it. The wicking action behaves differently in four different types of soils in the same volatilization experiment of 18% diesel oil content and air-dry condition.  相似文献   
912.
王政 《中国环境管理》2024,16(2):113-120
流域及其生态环境问题的特殊性引发行政治理体系的变革,系统论为流域生态环境行政治理体系的建构指明了方向,流域生态环境行政治理体系的建构是系统化的工程。在系统论指引下,结合相关规范性文件,流域生态环境行政治理系统的建构需从建立协调机制、规范职权行使与推进治理协同三方面切入,并分别明确三者在流域生态环境行政治理系统中的作用,通过建立议事协调机构发挥协调机制的统筹协调功能、通过整合与上收行政机关职权明确规范职权行使的实施功能、通过建立治理协同机制发挥推进治理协同的支持与保障功能。  相似文献   
913.
<正>修订后的《防震减灾法》完善了违法行为的责任追究制度:一方面,对管理部门违反法律规定或者行政不作为,应当承担的法律责任进行了规定;另一方面,对单位和个人违反法律规定应当承担的法律责任进行了规定。增加了处罚措施、加大了处罚力度。本法所规定的法律责任包括行政法律责任、民事法律责任和刑事法律  相似文献   
914.
<正>(四)明确了地震灾后恢复重建实施的要求、遵循的原则、善后处置、强化服务等方面的内容。1.本法第七十条规定了地震灾后恢复重建的原则、城市、乡村恢复重建的原则以及少数民族聚居地方恢复重建的特殊要求。地震灾后恢复重建中的统筹安排基础设施和市政公用设施、公共服务设施,以及住房和无障碍设施的建设总原则,是由政府的职  相似文献   
915.
上海在区间隧道上方建造风井在国内尚属首例。随着人们绿色环保意识的增强,隧道通风井将会越来越多地修建在远离都市核心区的区间隧道的上方,因而研究风口基坑施工引起区间隧道位移的变化将会是岩土工程领域的又一崭新问题。本文结合上海人民路隧道风井风口基坑工程,针对是否降低承压水水位2种工况,采用M IDA S-GTS软件,对既有盾构隧道隆起进行数值模拟,从理论上量化在这2种工况下隧道的变形程度,探讨该方法的可行性,为最终选择何种工况施工提供了理论指导。实际的监测数据验证了本文方法的可行性,为今后的相关工程建设提供了一个成功范例。  相似文献   
916.
2009年中国大陆地震灾害损失述评   总被引:4,自引:0,他引:4  
在列出2009年中国5.0级以上地震目录的基础上,结合年度有关省(自治区、直辖市)地震局的地震灾害评估资料,总结出2009年中国大陆地震灾害的主要数据和特性。最后对自1990年以来中国大陆地震灾害的相关数据进行了简要的比较。  相似文献   
917.
对城市群发展过程中的农业用地损失进行动态模拟研究,有助于准确归纳其损失的趋势和机制,为农业用地保护规划的制定提供依据。以长株潭城市群为例,通过遥感影像图的收集与处理以及空间数据库、方格网系统、十二向玫瑰图和三维山丘图的构建,对城市群扩张和农业用地损失的过程进行动态模拟,通过离心模型归纳导致农业用地损失的动力机制,并对2020、2025年的农业用地损失情况进行预测。结果显示:城镇建成区扩张是长株潭城市群农业用地损失最主要的原因。伴随着城市群空间结构的演变,农业用地损失经历了"中心区主导—中心区与产业园区共同主导—连绵式损失"的过程。如不加以控制,至2025年,一个总面积达1 500 km~2,呈连绵状分布的超大型都市区将在长株潭城市群形成,现有中心城区、产业园区之间的农业用地将逐渐消失殆尽,从而造成难以弥补的环境损失。从空间规划上优化城市群的空间结构和发展方式,从政策法规上对侵占行为进行严格控制,是保护农业用地的关键所在。研究有望为我国城市群环境保护规划的制定提供方法论参考。  相似文献   
918.
Wu  Tingting  Ma  Yuan  Wu  Xuan  Bai  Ming  Peng  Yu  Cai  Weiting  Wang  Yongxiang  Zhao  Jing  Zhang  Zheng 《Environmental science and pollution research international》2019,26(15):15262-15272

Ambient particulate matter (PM) pollution has been linked to elevated mortality, especially from cardiovascular diseases. However, evidence on the effects of particulate matter pollution on cardiovascular mortality is still limited in Lanzhou, China. This research aimed to examine the associations of daily mean concentrations of ambient air pollutants (PM2.5, PMC, and PM10) and cardiovascular mortality due to overall and cause-specific diseases in Lanzhou. Data representing daily cardiovascular mortality rates, meteorological factors (daily average temperature, daily average humidity, and atmospheric pressure), and air pollutants (PM2.5, PM10, SO2, NO2) were collected from January 1, 2014, to December 31, 2017, in Lanzhou. A quasi-Poisson regression model combined with a distributed lag non-linear model (DLNM) was used to estimate the associations. Stratified analyses were also performed by different cause-specific diseases, including cerebrovascular disease (CD), ischemic heart disease (IHD), heart rhythm disturbances (HRD), and heart failure (HF). The results showed that elevated concentration of PM2.5, PMC, and PM10 had different effects on mortality of different cardiovascular diseases. Only cerebrovascular disease showed a significant positive association with elevated PM2.5. Positive associations were identified between PMC and daily mortality rates from total cardiovascular diseases, cerebrovascular diseases, and ischemic heart diseases. Besides, increased concentration of PM10 was correlated with increased death of cerebrovascular diseases and ischemic heart diseases. For cerebrovascular disease, each 10 μg/m3 increase in PM2.5 at lag4 was associated with increments of 1.22% (95% CI 0.11–2.35%). The largest significant effects for PMC on cardiovascular diseases and ischemic heart diseases were both observed at lag0, and a 10 μg/m3 increment in concentration of PMC was associated with 0.47% (95% CI 0.06–0.88%) and 0.85% (95% CI 0.18–1.52%) increases in cardiovascular mortality and ischemic heart diseases. In addition, it exhibited a lag effect on cerebrovascular mortality as well, which was most significant at lag6d, and an increase of 10 μg/m3 in PMC was associated with a 0.76% (95% CI 0.16–1.37%) increase in cerebrovascular mortality. The estimates of percentage change in daily mortality rates per 10 μg/m3 increase in PM10 were 0.52% (95% CI 0.05–1.02%) for cerebrovascular disease at lag6 and 0.53% (95% CI 0.01–1.05%) for ischemic heart disease at lag0, respectively. Our study suggests that elevated concentration of atmospheric PM (PM2.5, PMC, and PM10) in Lanzhou is associated with increased mortality of cardiovascular diseases and that the health effect of elevated concentration of PM2.5 is more significant than that of PMC and PM10.

  相似文献   
919.

The purpose of this study is to investigate the enhancement of polycaprolactone (PCL) on total nitrogen (TN) removal of coal pyrolysis wastewater (CPW) with low COD to nitrogen ratio by partial nitrification-denitrification bioprocess (PNDB) in one single reactor. With the innovative combination of PCL and PNDB, the TN removal efficiency in the experimental reactor (signed as R1) was 10.21% higher than control reactor (R2). Nitrite accumulation percentage (NAP) in R1 was 82.02%, which was 17.49% higher than R2 at the dissolved oxygen (DO) concentration of 0.9–1.5 mg/L, for the reason that the extra DO was consumed by PCL biodegradation at the aerobic period. Gel permeation chromatography (GPC) results demonstrated that organics with the molecular weight of 185 Da, which could serve as additional carbon sources for denitrifiers, were generated during the PCL hydrolysis process at the anoxic period. PCL was hydrolyzed by extracellular enzymes with the break of the ester bond which was confirmed by FT-IR spectrometer. Microbial community analysis revealed that Ferruginibacter was the dominant hydrolysis bacteria in R1. Nitrosomonas were the main ammonium-oxidizing bacteria (AOB) and Hyphomicrobium were the denitrifiers in this study.

  相似文献   
920.
李亚红  周筝  赵小芳 《化工环保》2019,39(5):496-505
分析了国内水中余氯测定标准的现状,从标准适用范围、标准对象、方法原理、样品预处理、干扰物和方法的精密度等方面对现行标准进行了分析讨论,提出目前国内水中余氯测定标准存在现状复杂、技术内容重复、术语名称和定义不统一、样品预处理、保藏和运输规定与检测方法之间不协调、方法的质量指标不同等问题,并对今后余氯测定标准化工作提出建议,特别是针对标准对象名称混乱和技术内容重复等现象,对标准制/修订工作提出了及时复审或修订标准、对关键技术内容开展比对试验以探讨差异存在必要性等建议。  相似文献   
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