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131.
电除尘器进口喇叭的设计直接影响其气流均布。针对CFB—FGD干法烟气脱硫后的烟气特点,分析了处理脱硫后烟气的电除尘器进口喇叭设计,进行了气流分布试验,为高烟尘电除尘器进口喇叭的设计提供参考。  相似文献   
132.
Habituation and its role in the dear enemy effect was investigated in a population of green frogs, Rana clamitans. Green frogs have a prolonged breeding season, and males defend territories centered around suitable oviposition sites. We tested the prediction that male green frogs will habituate to broadcasts of synthetic conspecific stimuli. Our results indicate that male green frogs can discriminate familiar from unfamiliar stimuli. We suggest that habituation helps to mediate the territorial interactions between male green frogs. Strangers present a greater threat than familiar neighbors. By habituating to the advertisement vocalizations of their near neighbors, males avoid costly interactions with individuals that are not a major threat to their territories. Received: 20 July 1998 / Accepted after revision: 6 September 1998  相似文献   
133.
Debate exists as to what the more appropriate prediction is regarding the effects of multiple stigmatized group memberships on employment discrimination. The ethnic prominence (EP), multiple minority status (MMS), and subordinate male target hypotheses were assessed for the combined effects of ethnic group membership (Arabic), sex, social status, and job type on hiring evaluations. Two correspondence tests in the field (Study 1) and two experimental studies in the lab (Study 2) and in the field (Study 3) were conducted. Studies 1 and 2 showed evidence for the EP hypothesis when low‐status jobs were tested. The odds for rejection were four times higher for Arab than for Dutch applicants. Applicants' sex, socio‐economic status, and external client contact did not moderate findings (Study 1). The effect of applicants' ethnic group membership was further moderated by raters' motivation to control prejudice (Study 2). Study 3 showed evidence for the MMS hypothesis. We found double jeopardy against Arab women who applied for high‐status jobs when recruiters' prejudice was controlled. Study findings show that discrimination in resume screening may depend upon the particular intersection of applicant, job, and recruiter characteristics. We discussed implications for anonymous resume screening and research on evaluation of applicants possessing multiple stigmatizing characteristics. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
134.
恶臭污染物的排放与监测   总被引:2,自引:0,他引:2  
概括介绍恶臭污染源的形成、排放特征及恶臭污染物的监测技术,重点介绍了我国测定恶臭的国家标准方法“三点比较式臭袋法”及其实际操作中若干问题解析。  相似文献   
135.
ABSTRACT: A physically-based nomogram to determine inlet concentration times for composite developed basins is presented. This nomogram is constructed from previously derived kinematic wave formulations of both catchment and gutter flow components of surface runoff. With specified physical properties of a basin and rainfall intensity-duration relationships, the inlet time can be obtained from the nomogram directly.  相似文献   
136.
运用计算流体力学软件FLUENT模拟了平流式沉淀池在不同进水口高度,进水挡板位置,颗粒密度和圆弧形扰流板位置下的流场、悬浮物的浓度场。从模拟结果的分析比较可以看出,在一定范围内改变沉淀池的进水口高度,对沉淀池的去除效果没有影响。挡板的淹没深度和颗粒的密度则对悬浮物的去除效率影响较大。挡板的水平位置只在一定范围内变化才能使沉淀池保持较为理想的去除效率。圆弧形扰流板的加设可以改变沉淀池内流态不均的现象,从而提高沉淀池的运行效率。  相似文献   
137.
Religious harassment claims in the United States have risen sharply over the past decade. However, victims of religious harassment may not always report harassment, and true rates may be higher. Hence, actions taken by third parties present (observers) are important in combating harassment in the workplace. The purpose of this paper is to extend a previous model of observer intervention and related research by testing it empirically in the context of religious harassment and identify factors that influence observers' decision to intervene (intervention), when they intervene (level of immediacy), and how much they intervene (level of involvement). Across two studies, we find evidence that verbal harassment, ambiguity of intent, relationship to target/harasser, recurrence belief, religious commitment, pro‐social orientation, and the interactive effect of shared religion and religious commitment predict intervention. Furthermore, individuals show higher levels of involvement and immediacy in intervention when costs are low and emotional reactions are high. Implications of these findings for engaging observers in combatting harassment are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
138.
How is behaviour organised across sensory modalities? Specifically, we ask concerning the fruit fly Drosophila melanogaster how visual context affects olfactory learning and recall and whether information about visual context is getting integrated into olfactory memory. We find that changing visual context between training and test does not deteriorate olfactory memory scores, suggesting that these olfactory memories can drive behaviour despite a mismatch of visual context between training and test. Rather, both the establishment and the recall of olfactory memory are generally facilitated by light. In a follow-up experiment, we find no evidence for learning about combinations of odours and visual context as predictors for reinforcement even after explicit training in a so-called biconditional discrimination task. Thus, a ‘true’ interaction between visual and olfactory modalities is not evident; instead, light seems to influence olfactory learning and recall unspecifically, for example by altering motor activity, alertness or olfactory acuity.  相似文献   
139.
硅藻和甲藻的荧光识别测定技术研究   总被引:1,自引:1,他引:0  
基于浮游植物活体叶绿素荧光激发光谱建立了硅藻和甲藻的识别测定技术。根据Fisher判别分析结果,浮游植物活体叶绿素荧光激发光谱具有同门类藻谱形相似、不同门类藻谱形差异明显的特点,可作为硅藻和甲藻的识别特征谱,据此建立了浮游植物荧光特征谱库,并利用非负最小二乘法进行识别测定,其中单门类样品共有258个,识别正确率为98%,回收率≥79%;两个门类的混合样品共有18个,识别正确率为78%,回收率≥76%。  相似文献   
140.
沅江入湖河床沉积物重金属污染演化地球化学分析   总被引:4,自引:1,他引:4  
对沅江入湖河段河床沉积物进行钻探取样,利用电感耦合等离子质谱仪(ICP-MS)分析沉积物重金属等微量元素的含量,并利用210Pb法测定沉积物沉积速率.同时,在分析沉积物重金属污染特征的基础上,探讨沉积物重金属污染的演化过程.结果表明:沉积物中Bi、Cd、Mn、Mo、Zn、Pb等重金属含量变化大、分布不均匀,而Sc、Tl、Rb、Cs、V、Co、Zr、Hf、Nb、Ta、Ga、Ge、Rb、Sr、REEs(稀土元素)等微量元素含量变化小,分布相对均一.微量元素富集特征(EF值)和主成分分析结果显示,沉积物中Cu、Sc、Tl、Rb、Cs、Th、U、V、Co、Zr、Hf、Nb、Ta、Ga、Ge、Rb、Sr、REE等微量元素主要为自然源,而Bi、Cd、Mn、Zn、Pb等重金属则既有自然源的影响,又有人为源的贡献.地累积指数(Igeo)评价结果显示,入湖段沉积物存在Cd-Mn-Zn-Pb-Bi等元素组合的重金属污染,且沉积物自下而上分布有中深部(204~192 cm)、中上部(96~64 cm)、浅表部(64~0 cm)3个重金属污染层.上述3个重金属污染层可能对应于3个期次的重金属污染事件,即早期(1913年前)的零星重金属污染、中期(建国初期至改革开放初期,1963—1979年)的中等强度重金属污染、近期(1979年至今)高强度重金属污染.且自早期到近期,沉积物重金属污染程度增强,污染元素组合趋于复杂化.沅江入湖河床沉积物的上述3期重金属污染可能对洞庭湖沉积物产生直接影响.  相似文献   
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