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911.
From an international view, several papers have analysed how sustainability themes are integrated into the university curricula. In Spain, few studies to date have examined the extent to which universities are incorporating sustainability themes into their curricula. In view of such considerations, this article examines the extent to which sustainability themes are being incorporated into the curricula of a Spanish public university strongly committed to signing sustainability policies and declarations. In addition, this study analyses the main barriers to the incorporation of sustainability themes into the curricula of this university. To accomplish this task, this article uses different methodological instruments over three phases through a case study approach. The findings of this study suggest how the university examined has many difficulties in incorporating, holistically or separately, sustainability themes in its formal courses despite having so many policies, regulations and a commitment to sustainability.  相似文献   
912.
环保产业发展影响因素的理论分析与实证研究   总被引:2,自引:0,他引:2  
基于环境社会系统视角对影响环保产业发展的各种因素进行了理论分析,建立了定量分析模型,并对我国1995─2005年环保产业发展情况进行了实证分析.结果表明,影响我国环保产业发展程度从大到小的因素依次为经济发展水平、环境科技水平、环境状况、公众环境意识、环境保护法律法规.经济发展水平是影响我国环保产业发展水平的最主要因素,说明我国的环保产业尚处于起步阶段;环境科技水平是第二重要影响因素,反映出近年来我国在环保技术研发方面的投入较好地推动了环保产业的发展.因此,提升经济发展水平和加强环保技术研发是当前推动我国环保产业发展的有效举措.   相似文献   
913.
气体检测器及其在环境污染事故应急监测中的应用   总被引:6,自引:0,他引:6  
介绍了常用挥发性有机污染物(VOC)检测器的特性,并阐述了光离子化检测器(PID)的原理,特点及其在环境污染事故应急监测中的应用。  相似文献   
914.
束缚装置选型是新版中国标准中增加的一项重要内容,中国标准借鉴了美国标准和欧盟标准,但并未完全采用.因此,进行中国标准、美国标准和欧盟标准的比较研究非常重要.本文从人体坐标系、加速度区域和束缚装置准则三个方面对中国标准、美国标准和欧盟标准中的相关内容进行了全面对比,分析了各自的优缺点.在人体坐标系方面,中国标准定义较为合...  相似文献   
915.
从定性研究逐步向定量化分析发展,是土壤DDT残留时间研究的必然趋势。初步探讨了土壤中DDT残留时间的定量表征,设计出归一化的DDT残留时间指数(NRTI)作为定量表征土壤DDT残留时间的方法之一。根据对天津土壤中残留DDT的采样监测结果的计算和分析,发现NRTI在表征DDT的残留时间问题上,相对于传统方法有一定的改进。  相似文献   
916.
孙朔 《环境与发展》2020,(2):143-144
随着我国对于环境保护工作越来越重视,社会公众也越来越关注企业造成的环境污染问题,企业与政府有关部门的环境执法矛盾逐渐凸显出来。与政府有关部门的工作人员数量相比,存在废水、废气、固废排放现象的企业数量是庞大的,仅靠政府的环境执法明显力量不足,不能有效提高环境污染治理和资源保护的效果。企业自行监测是企业自觉遵守环境相关法律的重要行为,自行监测所得的信息也是政府环境执法的重要基础,本文从企业自行监测入手,分析企业自行监测工作存在的主要问题,探讨企业自行监测信息在环境执法中的应用方式和问题的主要对策,希望可以推动企业在环境执法中的参与度。  相似文献   
917.
陈颖  黄昌付 《环境与发展》2020,(4):162-162,165
大气污染作为环境污染的关键部分,一直困扰着人们的生活,而传统监测设备由于技术具有一定的滞后性,无法满足当前环境监测的需要。而网格化监测有着传统监测设备不具备的优势,在大气污染防治方面发挥着重要的作用,为环境污染治理提供重要的数据保障。基于此,本文主要对大气污染防治网格化监测含义及优势进行了总结概括,并重点对网格化监测的应用展开分析。  相似文献   
918.
Introduction: Crashes involving roadway objects and animals can cause severe injuries and property damages and are a major concern for the traveling public, state transportation agencies, and the automotive industry. This project involved an in-depth investigation of such crashes based on the second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) data including detailed information and videos about 2,689 events. Methods: The research team conducted a variety of logistic regression analyses, complemented by Support Vector Machine (SVM) analyses and detailed case studies. Results: The logistic regression results indicated that driver behavior/errors, involvement of secondary tasks, roadway characteristics, lighting condition, and pavement surface condition are among the factors that contributed significantly to the occurrence and/or increased severity outcomes of crashes involving roadway objects and animals. Among these factors, improper turning movements (odds ratio = 88), avoiding animal or other vehicle (odds ratio = 38), and reaching/moving object in vehicle (odds ratio = 29) particularly increased the odds of crash occurrence. Factors such as open country roadways, sign/signal violation, unfamiliar with roadway, fatigue/drowsiness, and speeding significantly increased the severity outcomes when such crashes occurred. The sensitivity analysis of the three SVM classifiers confirmed that driver behavior/errors, critical speed, struck object type, and reaction time were major factors affecting the occurrence and severity outcomes of events involving roadway objects and animals. Practical Applications: The study provides insights on risk factors influencing safety events involving roadway objects, including their occurrence and the severity outcomes. The findings allow researchers and traffic engineers to better understand the causes of such crashes and therefore develop more effective roadway- and vehicle- based countermeasures.  相似文献   
919.
Abstract

Metolachlor [2‐chloro‐N‐(2‐methoxy‐1‐methylethyl)‐2'‐ethyl‐6'‐methyl acetanilide] dissipation under both field and laboratory conditions were studied during summer season in an Indian soil. Metolachlor was found to have moderate persistence with a half‐life of 27 days in field. The herbicide got leached down to 15–30 cm soil layer and residues were found up to harvest day of the sunflower crop in both 0–15 cm and 15–30 cm soil layers. Metolachlor was found to be more persistent in laboratory studies conducted for 190 days. The rate of degradation was faster in soil under flooded partial anaerobic conditions as compared to aerobic soil with a half‐life of 44.3 days. In aerobic soil, metolachlor was very stable with only 49% dissipation in 130 days. Residues remained in both the soils up to the end of the experimental period of 190 days.  相似文献   
920.
Photolysis of oxyfluorfen, an herbicide of the nitrodiphenyl ether class, was studied in aqueous methanol under UV and sunlight. UV irradiation was carried out in a borosilicate glass photoreactor (containing 250 ppm oxyfluorfen in 50% aqueous methanol) equipped with a quartz filter and 125 watt mercury lamp (maximum output 254 nm) at 25 ± 1°C. Sunlight irradiation was conducted at 28 ± 1°C in borosilicate Erlenmeyer flasks containing 250 ppm oxyfluorfen in 50% aqueous methanol. The samples from both the irradiated conditions were withdrawn at a definite time interval and extracted to measure oxyfluorfen content by gas chromatography-flame ionization detector for rate study. The half-life values were 20 hours and 2.7 days under UV and sunlight exposure, respectively. Photolysis of oxyfluorfen yielded 13 photoproducts of which three were characterized by infrared spectrophotometer and 1H NMR and 13C NMR spectroscopy. The rest of the photoproducts were identified by gas chromatography-mass spectrometry (GC-MS) and thin layer chromatography (TLC). An ionization potential 70 eV was used for electron impact-mass spectrometry (EI-MS) and methane was used as reagent gas for chemical ionization-mass spectrometry (CI-MS). Two of the photoproducts were also synthesized for comparison. The main phototransformation pathways of oxyfluorfen involved nitro reduction, dechlorination, and hydrolysis as well as nucleophiles displacement reaction.  相似文献   
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