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901.
为研究煤吸附CO2在多因素耦合作用下体积的影响因素,采用HCA高压容量法测定不同条件煤样对CO2吸附量影响,并计算Langmuir体积,分析温度、粒径、含水率3种因素耦合影响煤对CO2吸附程度,通过Design Expert软件设计Box Behnken试验,构建煤吸附CO2的Langmuir体积二次回归响应曲面模型。结果表明:吸附量随温度、粒径增加而减小,随含水率升高呈先减小后稳定的趋势;影响因素中温度、粒径、含水率各单因素均为显著影响;多因素作用时影响程度大小依次为:粒径和含水率>温度和粒径>温度和含水率,温度和粒径、粒径和含水率之间交互作用显著,温度和含水率之间交互作用不显著。  相似文献   
902.
为给甘薯粉尘爆炸预防提供依据,用20 L球形爆炸装置进行爆炸试验,研究甘薯粉尘粒径、质量浓度和点火能量3个单因素对爆炸的影响;同时,用响应面方法,通过Design-Expert 软件中Box-Behnken试验设计,对影响甘薯粉尘爆炸的因素进行对比分析。试验结果表明,甘薯粉尘最大爆炸压力随粉尘粒径的减小而增大,随粉尘浓度的增加呈现先增加后减小的趋势,随点火能量的增大而增大。同时,由Box-Behnken试验中响应面回归方程知,甘薯粉尘质量浓度对粉尘爆炸影响最大,其次是点火能量,甘薯粉尘粒径对相应粉尘爆炸影响最小。  相似文献   
903.
为研究在巨大工作压力下,矿工的心理因素与工作压力反应和不安全行为的关系,以问卷的形式调查陕西省2家具代表性煤矿的工人,分别以矿工的心理因素、工作压力反应和作业过程中的不安全行为作为外生变量、中介变量和内生变量,构建心理因素、压力反应和不安全行为的结构方程模型。通过对调研数据处理与分析,得出如下结论:本研究中的4项心理因素,性格因素、心理素质、注意力和工作态度显著影响不安全行为的发生;性格因素、心理素质和注意力对压力反应有显著影响;工作态度与煤矿工人的压力反应的关系不显著;性格因素、心理素质、注意力和工作态度通过影响矿工的压力反应,间接影响矿工的不安全行为。  相似文献   
904.
本建立了广西西北部喀斯特石山地区可持续发展的系统动力学模型。并用DYNAMO程序预测了未来20年桂西北地区的人口、工业、农业、第三产业,生态环境,土地资源,社会总产值,人均国民收人等的动态变化趋势,结果显示,该地区由于人口,工业资产增加使物质和能源消耗增长太快,而对污染治理的投入又太少,导致桂西北地区的生存环境质量下降,因此应当加大对污染治理的投入力度,改善区域环境质量,这是实现息烽县区域可持续发展的关键,根据区域特点探讨了桂西北喀斯特贫困山区的形成演化,提出了可持续发展的途径。  相似文献   
905.
以秦皇岛市2011—2015年的噪声监测资料为依据,对\"十二五\"期间秦皇岛市声环境质量现状、变化趋势进行分析。分析结果表明:\"十二五\"期间秦皇岛市区域声环境和道路交通声环境质量为较好,功能区声环境昼夜全部达标;影响秦皇岛市环境噪声源主要为社会生活噪声、交通噪声等。提出了合理城区布局、使用新型隔声材料、加大宣传教育、严格环境执法等噪声污染防治对策。  相似文献   
906.
    
A firm's environmental technology portfolio comprises of a heterogeneous class of technologies, each with distinct economic and environmental implications. Having a portfolio with a proper mix of different technologies is critical in achieving economic and environmental goals. Using data on major United States’ corporates, I identify five types of environmental technologies: pollution control, eco‐efficiency, green design, low‐carbon energy, and management systems. I find that the composition of the environmental technology portfolio affects a firm's performance. Most notably, raising the share of low‐carbon energy and pollution control technologies in the portfolio can negatively affect economic performance. But both low‐carbon energy and pollution control are effective in improving carbon productivity. The other technologies do not display significant impacts on firm performance. The results highlight that firms should take the differential effects of environmental technologies into consideration when designing an adequate technology portfolio to attain desired economic and environmental objectives. Copyright © 2018 John Wiley & Sons, Ltd and ERP Environment  相似文献   
907.
    
Adaptation to climate change has been reviewed in several developed nations, but in none where consideration of the effects of climate change is required by statute and devolved to local government. We examine the role of institutional arrangements, the players operating under them, the barriers and enablers for adaptation decision-making in the developed nation of New Zealand. We examine how the roles and responsibilities between national, regional and local governments influence the ability of local government to deliver long-term flexible responses to changing climate risk. We found that the disciplinary practices of law, engineering and planning, within legal frameworks, result in the use of static mechanisms which create inflexible responses to changing risk. Several enablers are identified that could create greater integration between the different scales of government, including better use of national policy instruments, shared professional experience, standardised information collection and risk assessment methods that address uncertainties. The framing of climate risk as dynamic and changing that differentiates activities over their lifetime, development of mechanisms to fund transitions towards transformational change, are identified as necessary conditions for delivering flexible responses over time.  相似文献   
908.
为深入研究行人过街时使用手机对交通安全的影响,基于策略性反应-延迟理论(SRD),从社会心理学与行为心理学2个角度建立行人过街时使用手机的道路通行延迟效应(RTD)模型,通过问卷调查和实地观测,采用前后对比的研究方法,探寻不同手机使用方式所造成的延迟率。结果表明,同年龄段的男性使用手机过街的延迟率要高于女性,接打电话时的延迟率高于浏览手机时的延迟率,平均一次手机界面与路况观察的任务切换会造成0.34 s的时间延迟。  相似文献   
909.
    
The purpose of the research was to improve prediction of response of buildings to blast waves by including the negative phase and considering clearing of both positive and negative phases. Commonly used structural design practices, which trace their origins to military design manuals, often ignore the negative phase as well as positive phase clearing. For high explosive threats, this approach is conservative in most circumstances. However, negative phase clearing had not previously been studied for blast waves, and the implications for structural response had not been evaluated. This paper presents results of modeling negative phase blast clearing behavior for a typical blast wave and discusses the differences from positive phase clearing. The implications of including positive and negative phase clearing in building blast damage analysis are also investigated through single-degree-of-freedom (SDOF) analyses.Blast waves from explosion sources like a vapor cloud explosion (VCE), pressure vessel burst or high explosive exhibit both positive and negative phases, and the relative magnitude of the positive and negative phases varies among explosion sources and the specific circumstances of each source. A fully reflected blast wave is produced if an incident blast wave were to strike an infinitely tall and wide wall in a normal orientation. Both the positive and negative phases of the blast wave are enhanced by the reflection process. However, when an incident blast wave strikes a wall of finite size in a normal orientation, rarefaction waves are created at the edges of the wall, and the rarefactions sweep down from the roof and inward from sides. The rarefaction waves result in a clearing effect for both the positive and negative phases.Clearing relieves some of the applied blast load on the reflected wall for the positive phase. However, this is not always the case for the negative phase. As shown by the results presented in this paper, clearing may either relieve or enhance the applied negative phase blast load, depending on the duration of the blast wave and the wall dimensions.The impact of negative phase clearing on structural response for generic building components was also investigated. Nonlinear SDOF methods were used to characterize response in terms of peak positive and negative displacements. It was found that the influence of the negative phase is significant and the peak structural response can occur during negative (outward) displacement.  相似文献   
910.
    
This article presents a study on the effect of different protective gloves (which are commercially available and commonly used in the cold) on manual dexterity in cold environments. The experiments compared statistically four different types of gloves and two different types of gloving (outer or double) at +19 °C and -10 °C. Performance was determined both objectively and subjectively using two manual dexterity tasks: bolt-nut and pick-up tasks. The response measured was the time of performing each task. Statistical analysis showed that all independent factors such as glove type, participant, object size, and temperature had significant effects on the hand cooling reaction. A significant difference in the performance between the gloves was found in the bolt-nut task. It was also found that outer-inner combination gloving may be an approach to use for precision tasks.  相似文献   
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