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951.
基于卫星遥感指示剂法,以2017~2019年为基准年份,通过对比臭氧在线监测数据、VOCs和氮氧化物排放强度数据以及卫星遥感数据,在PM2.5重点监管区域的基础上,重新修订大气污染臭氧重点管控区,将我国臭氧年均浓度超标区(高于160μg/m3)划分为不同重点区域,识别每一个重点区域臭氧前体物敏感类型,即VOCs控制区、NOx控制区以及VOCs和NOx协同控制区,针对每种类型进一步细化为本地污染控制区和联防联控控制区,这种结合地面监测、统计调查数据和遥感观测数据的臭氧分区分类方法可以为大气污染的宏观分区分类管控提供一种新的思路,为国家出台全国层面臭氧污染防治及PM2.5和O3协同控制相关政策提供决策参考.  相似文献   
952.
乌克兰实行的是与环境影响评价制度相类似的生态鉴定制度,该制度在制度设计的完备性、科学性、合理性,特别是保障公众参与环境管理和直接参与生态鉴定活动方面具有十分显著的特点。在简要介绍乌克兰生态鉴定制度的基础上,探讨其确保公众参与的几种途径,以期对我国相关的立法与实践有所启示。  相似文献   
953.
Drawing on the perceived organizational membership theoretical framework and the social identity view of dissonance theory, I examined in this study the dynamics of the relationship between psychological contract breach and organizational identification. I included group‐level transformational and transactional leadership as well as procedural justice in the hypothesized model as key antecedents for organizational membership processes. I further explored the mediating role of psychological contract breach in the relationship between leadership, procedural justice climate, and organizational identification and proposed separateness–connectedness self‐schema as an important moderator of the above mediated relationship. Hierarchical linear modeling results from a sample of 864 employees from 162 work units in 10 Greek organizations indicated that employees' perception of psychological contract breach negatively affected their organizational identification. I also found psychological contract breach to mediate the impact of transformational and transactional leadership on organizational identification. Results further provided support for moderated mediation and showed that the indirect effects of transformational and transactional leadership on identification through psychological contract breach were stronger for employees with a low connectedness self‐schema. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
954.
A posture control model has been developed on the basis of the 2-dimensional feedback control theory. Human postural characteristics were investigated in 5 healthy participants. Tests were performed with eyes open and eyes closed. After 5 s of quiet standing, each participant was unexpectedly pulled forward by 30 mm at his pelvis height and then released. Postural sway was measured over 20 s at a rate of 100 per second. Transfer functions to represent the posture control characteristic were identified by the least squares' method. These showed good results of the model's fitness, predictability, and stability. The response of the eyes-closed condition to perturbation is more oscillatory than that of the eyes-open condition. It seems that the model identified could be applicable to ergonomics, sports, or clinical situations.  相似文献   
955.
危险化学品事故的频繁发生对人民生命财产和环境造成了巨大破坏,对危险化学品生产储存使用全过程实施安全监控和监管是有效减少和预防危化品事故的重要方法和手段.提出了危化品生产储存使用全过程安全监控与监管体系结构,论述了系统建设中进行危险辨识和风险分析的要求,详细讨论了动态安全监控与管理所涉及的采集监测、过程监控、安全分析、预警报警、应急联动、安全管理等主要技术内容及系统功能的设计.所提的技术方法和系统已在石化等企业进行示范应用,取得良好运行效果.  相似文献   
956.
1996年开始发布ISO14000系列标准后,次年我国即等同转化为国家标准。系列标准要求首先在组织内部建立和保持一个符合要求的环境管理体系,通过不断的审核和评价推动运行。标准分为评估组织和评估产品两大系列,其工作的实质内涵一是“改善”,二是“第三者监察”。  相似文献   
957.
Objective: This study aimed at identifying and predicting in advance the point in time with a high risk of a virtual accident before a virtual accident actually occurs using the change of behavioral measures and subjective rating on drowsiness over time and the trend analysis of each behavioral measure.

Methods: Behavioral measures such as neck bending angle and tracking error in steering maneuvering during the simulated driving task were recorded under the low arousal condition of all participants who stayed up all night without sleeping. The trend analysis of each evaluation measure was conducted using a single regression model where time and each measure of drowsiness corresponded to an independent variable and a dependent variable, respectively. Applying the trend analysis technique to the experimental data, we proposed a method to predict in advance the point in time with a high risk of a virtual accident (in a real-world driving environment, this corresponds to a crash) before the point in time when the participant would have encountered a crucial accident if he or she continued driving a vehicle (we call this the point in time of a virtual accident).

Results: On the basis of applying the proposed trend analysis method to behavioral measures, we found that the proposed approach could predict in advance the point in time with a high risk of a virtual accident before the point in time of a virtual accident.

Conclusion: The proposed method is a promising technique for predicting in advance the time zone with potentially high risk (probability) of being involved in an accident due to drowsy driving and for warning drivers of such a drowsy and risky state.  相似文献   

958.
自深圳某污水处理厂曝气池和二沉池的污泥中分离得到2株通过共代谢机制降解直链烷基苯磺酸钠(LAS)的细菌L-2和L-15。通过生理生化和16S rRNA基因序列分析,初步鉴定细菌L-2和L-15分别为Klebsiella sp.和Enterobacter sp.。研究表明:L-2和L-15以LAS作为唯一碳源时,对其降解率仅有1.1%和5.9%。当添加葡萄糖作生长基质,L-2在温度30℃,p H=7.5,m(葡萄糖)∶m(LAS)为20∶1的条件下,对50 mg/L的LAS的降解率可达94.2%;L-15在温度30℃,p H=7.5,m(葡萄糖)∶m(LAS)为16∶1的条件下,对50 mg/L的LAS的降解率可达92.2%。试验结果说明,筛选得到的2株细菌在共代谢的作用下,可以有效地实现废水中LAS降解。  相似文献   
959.
1株兼具好、厌氧汞甲基化能力细菌的分离鉴定   总被引:1,自引:0,他引:1  
陶兰兰  向玉萍  王定勇  黄曼琳  申鸿 《环境科学》2016,37(11):4389-4394
从三峡水库重庆段忠县石宝寨消落带土壤中,分离纯化后获得1株在好氧和厌氧条件下均能将Hg2+转化成甲基汞的细菌,经过对该菌株的形态特征、理化特征检测及16S r DNA序列分析,初步鉴定其为γ-变形菌纲的荧光假单胞菌,并命名为Pseudomonas fluorescens XD-Me Hg-B2(Gen Bank登录号:KU954349).通过汞敏感性试验发现该菌对Hg2+极敏感,汞甲基化试验表明,在初始Hg2+浓度为200 ng·L-1的PBS缓冲液中,接种XD-Me Hg-B2对数生长期菌悬液,有氧条件下,30℃孵育60 min后,溶液中甲基汞浓度呈指数增高,并在160 min时达到最大,约为3.85 ng·L-1±0.33 ng·L-1,最大汞甲基化率为1.93%;而在厌氧条件下,XD-Me Hg-B2同样表现出汞甲基化能力,但其甲基汞的生成较好氧处理显著滞后,且汞甲基化转化率较低,在180min左右甲基汞浓度达到最大,为2.86 ng·L-1±0.73 ng·L-1,最大汞甲基化率为1.43%.综上所述,P.fluorescens XDMe Hg-B2是1株对Hg2+极敏感,兼具好、厌氧汞甲基化能力的细菌,可望为消落带土壤汞生物甲基化的机制研究提供候选菌株,从而为深入研究汞生物地球化学循环、以及正确评价三峡水库蓄水运行后可能带来的汞生态风险评价提供理论依据.  相似文献   
960.
The extant literature on the relationship between self‐sacrificial leadership and subordinate behavioral outcomes has primarily focused on the influence of this leadership on subordinate affiliative behaviors. Our research proposed a theoretical model explaining why and when self‐sacrificial leadership might promote taking charge, an exemplar of challenging behaviors. We tested this model across two studies conducted in China. In addition, we also examined the differences in the boundary conditions for self‐sacrificial leadership to influence taking charge and affiliative behaviors (cooperation in Study 1 and helping in Study 2 ). Our results revealed that (i) self‐sacrificial leadership was positively related to subordinate taking charge, with organizational identification acting as a mediator for this relationship, and (ii) risk aversion moderated both the self‐sacrificial leadership–subordinate taking charge relationship and the mediating effect of organizational identification, such that the relationship and its mediating mechanism were weaker for subordinates high rather than low in risk aversion. These moderating effects, however, could not generalize to cooperation and helping. Finally, the theoretical and practical implications of our results and directions for future research were discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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