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151.
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Guangna Xie Yu Chen Ke Bei Zhipeng Gao Mingde Yang Junliang Wang 《International Journal of Green Energy》2017,14(11):861-867
A fused silica capillary reactor combined with a heating/cooling stage, a microscope and a digital camera were used to investigate phase behavior during the hydrothermal liquefaction of microalgae (Dunaliella tertiolecta) and model compounds, including soya protein and glycine, starch, glucose and xylose, stearic acid and palmitic acid. Bubbles were generated at 246°C and disappeared at 360°C upon heating when Dunaliella tertiolecta used as feedstocks. Moreover, liquid products were generated at 300°C upon heating and oily liquid products began to separate out at 250°C upon cooling. The phase behavior of soya protein was similar to that of the Dunaliella tertiolecta. Meanwhile, there only observed the bubbles generation during hydrothermal liquefaction of glycine. Heating the starch, glucose and xylose above 350°C generated black solids from carbonization. Stearic acid and palmitic acid only had the process of melting, dissolution, dispersion and precipitation. 相似文献
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Despite annual increases in the amount of material solid waste (MSW) that is recycled in the United States, the overall amount of MSW generated continues to increase. In an effort to identify and test specific predictors of curbside recycling behavior, the current study adapted the empirically validated Information–Motivation–Behavioral Skills model (IMB), traditionally used to predict personal health behavior, to explain curbside recycling behavior. Using structured computer assisted telephone surveys with two random community samples; structural equation models indicated that the IMB model significantly predicted curbside recycling. Data from the current study provides specific information about critical psychosocial determinants of curbside recycling behavior and public policy implications. 相似文献
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A time‐lagged investigation of the impact of coworker behavior on the effects of demographic dissimilarity 下载免费PDF全文
Although it is clear that coworker absenteeism, tardiness, and turnover can influence an employee's actions, scholars have yet to consider the impact of relational demography on the adoption of these behavioral norms. Inspired by social identity, situational strength, and attraction‐selection‐attrition theories, we proposed that individuals who differ from their coworkers in age, sex, or racioethnicity would feel threatened by their outnumbered status and subsequently motivated to be absent, tardy, or more likely to turnover. However, we expected coworker withdrawal behavior to moderate whether or not dissimilar personnel act on these desires. Results from hierarchical multilevel modeling analyses of data from 470 U.S. call center workers nested in 51 work groups revealed that racioethnic dissimilarity was positively related to time‐lagged changes in absenteeism and tardiness as well as heightened turnover likelihood. These effects emerged only among employees whose coworkers engaged in greater withdrawal behavior. Importantly, racioethnically dissimilar employees working in more permissive climates (i.e., those with high levels of coworker absenteeism, tardiness, or turnover) exhibited the greatest increases in absenteeism and tardiness over three months and had the highest supervisor‐rated turnover likelihood. Implications for diversity management are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
157.
Perceived prosocial impact,perceived situational constraints,and proactive work behavior: Looking at two distinct affective pathways 下载免费PDF全文
This paper examines the role of affect as a linking mechanism between experiences at work (perceived prosocial impact and situational constraints) and two distinct components of proactive work behavior (issue identification and implementation). Based on a dual‐tuning perspective, we argue that both positive affect and negative affect can be beneficial for proactive work behavior. Multi‐level path analysis using daily‐survey data from 153 employees showed that perceived prosocial impact predicted positive affect and that situational constraints as a typical hindrance stressor predicted negative affect. Negative affect, in turn, predicted issue identification, and positive affect predicted implementation. Overall, our study suggests that both positive and negative affects can be valuable in the organizational context by contributing to distinct components of proactive behavior. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
158.
绿灯倒计时信号对驾驶行为的影响 总被引:1,自引:0,他引:1
为揭示绿灯倒计时信号对交叉口交通安全的影响,针对不同交通负荷与信号控制方式下的驾驶行为开展研究。选择大连市内的倒计时信号交叉口与非倒计时信号交叉口各2处,开展车辆行驶速度及不良驾驶行为调查。用数理统计方法,对比分析2类交叉口在平峰与高峰时段的车辆行驶速度特性,同时对比分析上述不同条件下闯黄灯及违规变道行为的发生数量。研究表明,绿灯倒计时信号在绿灯时间末期,会诱发一部分驾驶员加速行驶通过交叉口;绿灯倒计时信号在平峰时段对闯黄灯行为数量的影响较小,而对违规变道行为的数量有显著影响。 相似文献
159.
The driving attitudes and self-reported behaviors of New Zealand adolescents in Year 10 of school (n = 168, mean age = 14.2 years) were compared with students in Year 12 (n = 109, mean age = 16.4 years). School year group differences were found for three out of the eight measures of risky attitudes and behaviors, with the older students having riskier responses in each case. Gender differences were found for four of these measures, with males consistently demonstrating riskier attitudes. Suggestions are made about appropriate interventions and the timing of these. 相似文献
160.
回燃及其对腔室火灾过程的影响 总被引:8,自引:0,他引:8
从火灾中的两种特殊火行为-轰燃和回燃的发生机理出发,着重讨论了回燃在整个火灾过程中的作用以及回燃对轰燃的影响。结果表明,由于回燃和轰燃同为火灾全过程中的分过程,并且由于二者发生机理的相似性,因而,它们可以建立联系。当具备合适的热解产物浓度时,回燃过程可以使火灾系统的状态突变到完全发展状态,即引发轰燃。 相似文献