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111.
The contemporary work environment is characterized by an ongoing trend to embed employees in teams because of their expected abilities for handling complex tasks and integrating diverse sets of knowledge and skills. However, leveraging this potential is endangered by stimuli within and outside of teams that take a toll on cohesion and teamwork among team members. Understanding the role that stressors and demands play in the work-related functioning of teams and their members is therefore an increasingly important challenge in the organizational behavior literature. Whereas research on stressors and demands has primarily focused on the individual level, we expand the research scope by considering these phenomena to be multilevel. We perform an interdisciplinary review of the literature on these stimuli in teams and show how related research, such as that on destructive leadership, may benefit from a more balanced account and integration of frameworks on stressors. Our multilevel review is informative for the literature on stressors and demands at the individual and team levels, as it offers an important conceptual grounding for how and why various stimuli in this social environment differentially influence both the collective entity and its individual team members.  相似文献   
112.
《火灾科学》2012,21(1)
主要研究低压环境下,压力、温度对氮气和氧气分别在航空煤油中溶解度的影响。实验装置包括除气装置、吸气平衡装置以及称重装置。由实验结果可知:压力在0MPa~0.1MPa,温度为293.15K,303.15K,313.15K时,氮气和氧气分别在航空煤油中的溶解度与压力呈线性关系、与温度呈非线性关系;氮气在航空煤油中的溶解度受压力的影响比氧气的小,受温度的影响比氧气的大;氧气在航空煤油中的溶解度比氮气的大。  相似文献   
113.
Efficient composting process requires set of adequate parameters among which physical–chemical properties of the composting substrate play the key-role. Combining different types of biodegradable solid waste it is possible to obtain a substrate eligible to microorganisms in the composting process. In this work the composting of apple and tobacco solid waste mixture (1:7, dry weight) was explored. The aim of the work was to investigate an efficiency of biodegradation of the given mixture and to characterize incurred raw compost. Composting was conducted in 24 L thermally insulated column reactor at airflow rate of 1.1 L min?1. During 22 days several parameters were closely monitored: temperature and mass of the substrate, volatile solids content, C/N ratio and pH-value of the mixture and oxygen consumption. The composting of the apple and tobacco waste resulted with high degradation of the volatile solids (53.1%). During the experiment 1.76 kg of oxygen was consumed and the C/N ratio of the product was 11.6. The obtained temperature curve was almost a “mirror image” of the oxygen concentration curve while the peak values of the temperature were occurred 9.5 h after the peak oxygen consumption.  相似文献   
114.
A series of cobalt doped TiO_2(Co-TiO_2) and Co Oxloaded TiO_2(Co/TiO_2) catalysts prepared by sol–gel and impregnation methods respectively were investigated on selective catalytic reduction with NH_3(NH_3-SCR) of NO. It was found that Co-TiO_2 catalyst showed more preferable catalytic activity at low temperature range. From characterization results of XRD,TEM, Raman and FT-IR, Co species were proved to be doped into TiO_2 lattice by replaced Ti atoms. After being characterized and analyzed by NH_3-TPD, PL, XPS, EPR and DRIFTS, it was found that the better NH_3-SCR activities of Co-TiO_2 catalysts, compared with Co/TiO_2 catalyst, were ascribed to the formation of more oxygen vacancies which further promoted the production of more superoxide ions(O-2). The superoxide ions were crucial for the formation of low temperature SCR reaction intermediates(NO-3) by reacting with adsorbed NO molecule. Therefore, these aspects were responsible for the higher low temperature NH_3-SCR activity of Co-TiO_2 catalysts.  相似文献   
115.
• Liquid digestate humification was investigated under different oxidizing environment. • Tryptophan-like substances dominated the transformation of the liquid digestate DOM. • The humification sequence of the liquid digestate DOM was identified. • UV325 was first identified as a pre-humus intermediate during humification reaction. The formation of humic-like acids (HLAs) is an essential process for converting liquid digestate into organic soil amendments to enhance agricultural sustainability. The aim of this study was to investigate the impact of oxygen and/or MnO2 on the production of HLAs. Herein, abiotic humification performance of the digestate dissolved organic matter (DOM) is investigated with fluxes of air and N2 in the absence and presence of MnO2. Our results demonstrated that the fate of digestate DOM greatly depends on the oxidizing environment, the MnO2 enhanced nitrogen involved in the formation of HLAs. The synergistic effects of MnO2 and oxygen effectively improved the production of HLAs, and the corresponding component evolution was analyzed using spectroscopic evidence. The two-dimensional correlation spectroscopy results demonstrated that the reaction sequence of digestate DOM followed the order of protein-like substances, substances with an absorbance at 325 nm, substances with UV absorbance at 254 nm and HLAs. Additionally, excitation emission matrix fluorescence combined with parallel factor analysis (EEM-PARAFAC) showed that tryptophan-like C3 was more prone to transformation than tyrosine-like C2 and was responsible for the humification process. The substance with an absorbance at 325 nm was a reaction intermediate in the transformation process of protein-like substances to HLAs. The above findings can be used to promote the production of liquid fertilizer associated with carbon sequestration as well as the sustainable development of biogas production.  相似文献   
116.
通过对一台储氧卧罐检验结果的分析及对历次检验情况的比较,建议对这台容器进行判废处理。但由于生产需要,该容器不能立即更新,专家们根据实际情况提出了用声发射仪监控,延长使用期一年的意见。  相似文献   
117.
Respirograms of activated sludge OUR_ x~Tand OUR_x~(20)were measured under site(T) and standard(20°C) temperatures, respectively, and the predicted standard temperature respirogram OUR_( x,cal)~(20)was also calculated using the Arrhenius equation. These respirogram profiles reveal more information than effluent quality. A decrease of OUR_ x ~(20)is a critical alarm signal for the loss of pollutant removal capacity, and a sudden increase of the predicted value OUR_( x,cal)~(20)is an alarm signal for the unrecoverable deterioration of biomass. The sign of OUR_x~(20)–OUR_(x,cal)~(20)can be used for selection of tuning strategies. For example, a negative value of OUR_x~(20)–OUR_( x,cal)~(20)indicates that doubling biomass is difficult,thus strategies such as extending the reaction time with limited available biomass is preferred. The findings in this study elucidated the respiration profile of activated sludge under changes of temperature and can be effectively used for the stable operation of Wastewater Treatment Plants under cold temperatures and seasonal variations.  相似文献   
118.
There is an urgent need for developing cost-effective methods for the treatment of perfluorooctanoic acid(PFOA)due to its global emergence and potential risks.In this study,taking surface-defective BiOCl as an example,a strategy of surface oxygen vacancy modulation was used to promote the photocatalytic defluorination efficiency of PFOA under simulated sunlight irradiation.The defective BiOCl was fabricated by a fast microwave solvothermal method,which was found to induce more surface oxygen vacancies than conventional solvothermal and precipitation methods.As a result,the asprepared BiOCl showed significantly enhanced defluorination efficiency,which was 2.7 and33.8 times higher than that of BiOCl fabricated by conventional solvothermal and precipitation methods,respectively.Mechanistic studies indicated that the defluorination of PFOA follows a direct hole(h~+)oxidation pathway with the aid of·OH,while the oxygen vacancies not only promote charge separation but also facilitate the intimate contact between the photocatalyst surface and PFOA by coordinating with its terminal carboxylate group in a bidentate or bridging mode.This work will provide a general strategy of oxygen vacancy modulation by microwave-assisted methods for efficient photocatalytic defluorination of PFOA in the environment using sunlight as the energy source.  相似文献   
119.
职业是经济社会分层的表征,职业指导随着经济社会和职业的发展应运而生。从就业形势、社会对高校人才培养的要求及大学毕业生职业核心竞争力缺失等方面对高校就业工作现状进行了分析,提出将职业指导融入人才培养机制、目标、方法和内容等各个层面,实现大学生有序就业,完成高校办学与社会需求之间的有效对接。  相似文献   
120.
We theorized that organization–environment adaptation, the interaction between external demands and personnel resources, predicts distress and morale. We tested this hypothesis in 29 stations within one state police department, and combined three data sources. We measured environmental demands for policing via census data pertaining to the station precinct (e.g., per cent unemployed; per cent in public housing). We assessed resources via personnel numbers within stations. Outcomes were employee's perceptions of staff distress and morale at the station (N = 247), assessed twice, 14 months apart. Using hierarchical linear modeling, we found that environmental demands predicted perceptions of workgroup distress and morale and that the relationships were moderated by personnel resources. For distress, when resources were low, demands were positively associated with distress; when resources were high, demands were negatively associated with distress. For morale, when resources were high, demands were positively associated with morale; there was no relationship when resources were low. Results show that aversive and pleasurable reactions at work may be traced to how resources are employed to manage external demands. Results support a macro‐level shift in modeling distress and morale, incorporating external demands, and strategic management decisions regarding personnel resourcing. Our research suggests that rather than being a result of individual failure to adapt, compromised work ability may result from an organizational failure to adapt to the environmental context. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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