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621.
于2019年8—9月,采用大气预浓缩-气相色谱质谱联用仪(GC-MS)对泰州市3个监测点位环境空气中57种挥发性有机物(VOCs)进行分析,并开展了VOCs组成特征、臭氧生成潜势(OFP)、VOCs来源及健康风险评价研究。结果表明:3个点位环境空气中φ(VOCs)范围为1.3×10^(-9)~46.9×10^(-9),平均值为8.5×10^(-9)。烷烃在VOCs中所占比例最大。各点位φ(VOCs)平均值依次为:工业园区>公园路>天德湖公园。公园路点位VOCs中苯系物受汽车尾气排放影响较大,天德湖公园和工业园区点位除了受汽车尾气排放影响,还受到有机溶剂和涂料的挥发影响,主要受本地污染主导。OFP中贡献最大的物质为乙烯,OFP值为5.5μg/m^(3),其次为烷烃。健康风险评价结果显示,各点位VOCs非致癌类风险均较低,处于安全范围内。各点位夏季环境空气中苯对人体均具有一定致癌风险。  相似文献   
622.
武陵源风景名胜区水环境调查   总被引:4,自引:0,他引:4       下载免费PDF全文
对武陵源风景区水体富营养化现状和演变趋势进行了调查。结果表明,总磷为武陵源风景区水体首要污染因子;金鞭溪、索溪水库、索溪组成的主干水体已处于富营养化状态,且呈上升趋势。提出,彻底进行生态大拆迁,减少核心景区旅游接待和商业行为;建立用水价格市场体系,降低污水排放量;合理规划旅游接待区,推行绿色宾馆酒店建设,加强水污染治理,减少污染物排放量;加强科学投入,确定水环境容量,合理控制旅游容量,是根治景区水体富营氧化污染的有效途径。  相似文献   
623.
For an accident involving a large-scale internal floating-roof tank with 28.4 m diameter and filled with 4600 m3 gasoline, the actual behavior of the gasoline fire and the fire-fighting strategies that were applied to it were analyzed in terms of the heat release rate, burning rate, and regression rate. During the accident, the initial fire suppression strategy failed and the gasoline was moved to an external tank. A total of 2800 m3 gasoline was burned for 17 h with a resulting heat release rate of 1475 MW. The long duration of the fire burning was attributed to the burning surface of the gasoline, which was not covered with foam at the beginning of the fire using the active foam fire-extinguishing system due to damage to one of the foam chambers. The average regression rate of the gasoline was 0.16 m/h after 8 h of burning and 0.35 m/h when the fire was completely suppressed.  相似文献   
624.
Introduction: Concussion is a type of traumatic brain injury that can be sustained through participation in different sports. It is important that a parent be able to identify common and uncommon symptoms of a concussion to ensure the safety and good health of their child. The purpose of this study was to compare knowledge of concussion scores among White and African American parents and guardians. Methodology: This cross-sectional study consisted of a single survey of 53 questions that was given to parents/guardians of high school athletes at a preseason parent meeting. Parent and guardian knowledge of concussion was assessed through a series of 45 questions. Participants were asked to correctly identify signs and symptoms of concussion, answer questions regarding the anatomy of a concussion (i.e. a concussion is an injury to the brain), answer true/false questions about general concussion knowledge, select from a list the consequences of multiple concussions and select from a list the consequences of returning to play too soon from a concussion. Knowledge of concussion was calculated by summing correct responses for the 45 knowledge questions. Racial differences were calculated using an ANCOVA, controlling for socioeconomic school type. The statistical significance level was set a priori p ≤ 0.05 for all analyses. Results: Participants of this study consisted of 176 [115 (65.3%) White, 61 (34.7%) African American] parents/guardians of high school athletes. Significant differences in knowledge of concussion scores between White parents/guardians [38.50 ± 4.55 (85.6% correct)], and African American parents/guardians [35.15 ± 4.97, 78.1% correct)] were identified (F(1,172) = 4.82, p = 0.03). Conclusion: Knowledge of concussion disparities exist between African American and White parents/guardians. This disparity could cause complications from concussion to surface among children and adolescents participating in sport as their parents/guardians may not be able to correctly identify the signs and symptoms in order to seek proper medical care. Practical Application: Findings from this study highlight quantitative differences in concussion knowledge of parents from different demographics. These findings underline disparities and inequities in access to concussion-health resources that need to be addressed.  相似文献   
625.
本文根据可接受风险标准的确定方法和制定原则,提出了中石油企业可接受风险标准,包括员工个人可接受风险标准和员工社会可接受风险标准。  相似文献   
626.
This study analyzes and assesses the integrated health, safety, environment (HSE) and ergonomics (HSEE) factors by fuzzy cognitive maps (FCM) approach. This is achieved through integrating ergonomic and macro-ergonomic as well as occupational health and safety arrangements in an integrated modeling for assessment of their multi-faceted impact on workers' productivity, injury rate and satisfaction. This paper uses FCM to assess the direct and indirect effects of HSEE factors on system performance indicators. The results of FCM are used to develop leading indicators useful for proactive management of productivity, injury rate, and job satisfaction. The result of a comprehensive survey of 37 experts in control rooms and maintenance activities in a large gas refinery is used to show the applicability and usefulness of FCM approach. Moreover, FCM results are used to determine the causal structure of HSEE factors and system performance indicators. It is concluded that macro-ergonomics factors such as instructions and education, familiarity with organization's rules, and proper communications most contribute to improve workers' safety, satisfaction, and productivity.  相似文献   
627.
高阳  吴浩  李鑫  蔡顺  熊巨华 《自然资源学报》2022,37(12):3049-3059
支持基础研究是国家自然科学基金的职责使命。自然资源管理是地理科学交叉融合创新的重要领域。划分国家自然科学基金土地科学和自然资源管理申请代码领域的研究方向,分析该领域申报与资助格局,透视研究热点,提出发展展望。研究发现:2021年以来土地科学和自然资源管理领域的申报格局以交叉且偏向人文要素研究为主,交叉类研究占55%以上,人文要素为主类研究占30%,自然要素为主类研究占15%;以土地资源为对象研究占73%,以生态资源为对象占14%,以其他自然资源为对象的研究占13%。资助格局中土地资源类项目占主导,在75%以上,其他自然资源资助比例不高且资助率不稳定,在土地资源中,农用地、建设用地与土地系统是主要资助领域。为推动自然资源管理领域的健康持续发展,要创新该领域研究范式,增强基础研究属性,树立交叉融合研究典范,坚持申请代码初衷内涵。  相似文献   
628.
As the discipline of conservation biology evolves and practitioners grow increasingly concerned about how to put results into achievable conservation, it is still unclear the extent to which science drives conservation outcomes, especially across rural landscapes. We addressed this issue by examining the role of science in the protection of a biological corridor. Our focus is on a North American endemic mammal reliant on long distance migration as an adaptive strategy, the pronghorn (Antilocapra americana) of the southern Greater Yellowstone Ecosystem. The role of science in realizing policy change, while critical as a first step, was surprisingly small relative to the role of other human dimensions. In a case study, we strategically addressed a variety of conservation needs beyond science, first by building a partnership between government and private interests and then by enhancing interest in migratory phenomena across a landscape with divergent political ideologies and economic bases. By developing awareness and even people's pride in the concept of corridor conservation, we achieved local, state, and federal acceptance for protection of a 70 km long, 2 km wide pathway for the longest terrestrial migrant in the contiguous United States. Key steps included conducting and publishing research that defined the migration corridor; fostering a variety of media coverage at local, regional, and national levels; conducting public outreach through stakeholder workshops, meetings, and presentations; and meeting with and gaining the support of elected officials. All these contributed to the eventual policy change that created the first federally protected migration corridor in the United States, which in turn stimulated additional conservation actions. On the basis of our experience, we believe conservation scientists can and should step beyond traditional research roles to assist with on‐the‐ground conservation by engaging in aspects of conservation that involve local communities and public policy. Ir Más Allá de la Ciencia para Proteger un Corredor Migratorio de Mamíferos  相似文献   
629.
为揭示景观格局内演机制,在3S技术平台支撑下,借助TM遥感像图、植被分类图和二类调查数据,并引入CCA(Canonical Correspondence Analysis)排序方法,对天宝岩森林景观格局与环境的关系及其尺度效应进行定量分析.结果表明:随着取样尺度的递减,排序轴各特征值之和呈增大趋势,依次为:3.137、3.349、3.484、4.660及4.848;而累积景观–环境解释量和景观–环境相关系数皆呈先增后减的趋势,分别在scale3和scale2达到最大;景观类型分布呈现较为明显的纬度梯度变化规律(纬度与第一轴的相关系数:-0.2019~-0.3789)和垂直分布规律(海拔与第一轴的相关系数:-0.3218~-0.4760),其中沿纬度梯度上分布的景观类型依次为:竹林、落叶阔叶林、针阔混交林、农田、常绿阔叶林、山顶矮曲林、常绿针叶林、泥潭藓沼泽、灌草丛;在较低海拔上分布的景观类型主要有竹林和农田,在较高海拔上分布着泥潭藓沼泽、灌草丛和山顶矮曲林;景观格局与环境关系具有尺度效应,环境因子对景观格局分布的影响程度随着尺度的变化而变化.图2表2参36  相似文献   
630.
于2006~2007年9~10月间采用样线样带法研究了甘肃兴隆山自然保护区马麝的秋季生境利用特征,共布设286个空白对照样地和55个利用样地,测量并比较两类样地内的海拔等17个生境变量.结果表明,马麝秋季利用样地的乔木密度(0.90±0.14)和灌木均高(1.92 m±0.53 m)显著低于非利用样地(乔木密度1.35±0.07;灌木均高3.01 m±0.53 m),而且距水源距离(<1 000 m,76.37%)和人为干扰活动距离(<1 000 m,76.36%)较近的中下坡位生境(82.82%)(P<0.05).对喜好生境变量的主成分分析表明,地理因子(由海拔、水源距离、植被类型和坡向构成)是制约兴隆山马麝秋季栖息地选择的首要因子,此外,郁闭度因子(由郁闭度和坡度构成)、食物因子(由食物多度和乔木胸径构成)和隐蔽因子(由隐蔽度和避风性构成)也是影响兴隆山马麝秋季生境选择的重要因素.由于秋季对食物和水源的强烈选择,兴隆山马麝对生境隐蔽性和距人为干扰距离的选择强度较低,即承受较大强度的人为干扰.表5参31  相似文献   
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