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61.
We conduct a meta‐analytic review that yields important insights about the existing research on transformational leadership and creativity. Additionally, we propose and test an integrated model using meta‐analytic structural equation modeling (MASEM) and full information MASEM (FIMASEM) techniques to better understand the intervening mechanism through which transformational leadership acts on creativity. The results of the meta‐analysis of 127 studies show that most of the bivariate relationships among transformational leadership, employee creativity, and pre‐identified mediators are significant; further, geographic base of studies significantly moderates some of the relationships. The MASEM results indicate that several mediators intervene in the relationship between transformational leadership and creativity. Although the total effect of transformational leadership on creativity is positive, its direct effect is negative when mediators are included. Additionally, there are significant relationships among the mediators that can be theoretically supported, but have not been investigated in prior transformational leadership and creativity studies. On the basis of these findings, we provide conclusions and directions for future studies.  相似文献   
62.
中国经济增长对碳排放的影响分析   总被引:43,自引:1,他引:43  
通过相关分析探讨了中国国内生产总值(GDP)的增长与碳排放量的关系.结果表明,二者有明显的相关性(R2=0.958 1).进一步研究认为,由于中国投资率在35%~40%以上,且工业增加值占GDP的比重超过50%,因此中国过分依赖投资的经济增长方式和以第二产业(工业)为主的经济结构在很大程度上是导致温室气体排放量增加的主要原因.未来在全球化背景下,经济增长可转变为更多地依靠科技创新、技术进步和制度的改进,因此,调整经济增长方式和产业结构,可以在保持发展经济的同时,使碳排放强度呈逐渐下降的趋势.  相似文献   
63.
Riedl J  Altenburger R 《Chemosphere》2007,67(11):2210-2220
In the last years many efforts were made to transform standardized algal test protocols into low-cost microplate assays. While advantages were pointed out frequently, limitations are not systematically addressed, thus hindering a widespread utilisation. In this study a group of organic substances with a wide distribution of volatility (log KAW from −6.53 to −2.13) and lipophilicity (log KOW from 1.26 to 4.92) was investigated with respect to the influence of these physicochemical properties on their algal toxicity in different assays. Therefore the EC50 values were determined with a microplate assay based on ISO 8692 protocol and the results were compared with those of an established algal growth inhibition test conducted in air tight glass vessels. Using the ratio of the EC50 values, a clear connection between biological response and volatility as well as lipophilicity of test substances could be detected. Chemicals with a log KOW higher than 3 or a Henry coefficient log KAW higher than −4 were identified as less effective in the microplate assay than in the comparative assay. The loss in nominal concentration due to physicochemical properties could be shown to contribute to this using HPLC analysis. Consequently, when using microplate assay’s one should be aware that lipophilic and volatile chemicals might be underestimated in their toxicity, which could be indicated from evaluating related physicochemical properties modelled from structural information prior to an experimental investigation.  相似文献   
64.
黄钠铁矾渣制备透明氧化铁黄的研究   总被引:3,自引:0,他引:3  
研究了以黄钠铁矾渣为原料,采用滴加法制备透明铁黄的工艺条件,讨论了亚铁浓度、温度、通气量、搅拌速度及添加剂用量等因素对铁黄制备的影响.用XRD和TEM对产品进行表征.结果表明,铁黄粒子呈针状;长轴为95~125 nm,短轴为18~25 nm;无团聚现象,单分散性好.  相似文献   
65.
以洗衣粉中的有机磷为磷源,通过室内模拟的方法研究在不同磷浓度的水体条件下斜生栅藻的生长情况,以及磷对斜生栅藻的生长是否有毒害作用.通过显微计数测定藻细胞数目来探讨洗衣粉中磷对斜生栅藻生长的影响;同时分析了洗衣粉中磷对斜生栅藻96 h生长期中光合色素的影响.结果表明,洗衣粉中的磷除了促进藻生长外,其浓度过低或过高都会抑制藻的生长.由实验结果可得,磷对藻生长的富营养化作用和毒性作用取决于磷浓度的高低.  相似文献   
66.
Hu Z 《Chemosphere》2008,72(2):312-318
The biokinetics of attached and suspended bacteria are an essential component of activated sludge models, anaerobic digestion models and biofilm models. These parameters are often assumed or “confirmed” based on the goodness-of-fit of the bioprocess models. Using a microbial fuel cell with a baffled reactor chamber, the attached- and mixed-growth microbial decay coefficients were evaluated under anaerobic conditions. The capability for real-time voltage recording allows easy and accurate measurement of the anaerobic microbial decay coefficients (bL, lysis-regrowth approach), which were determined to be 0.11 ± 0.01 and 0.15 ± 0.01 d−1 for attached (to anode) and mixed (present in the anode chamber) growth microorganisms, respectively. The corresponding half-saturation constants using glucose as a substrate were 204 ± 10 and 123 ± 1 mg COD l−1. Hence, like an oxygen uptake rate-based approach to measure the microbial kinetics under aerobic conditions, the electrochemical recording provides an attractive method to measure anaerobic microbial decay coefficients.  相似文献   
67.
矿化垃圾混配种植介质的盆栽实验研究   总被引:1,自引:1,他引:1  
矿化垃圾营养成分和有机质含量较高,但含有重金属和盐分.为了解矿化垃圾的施加比例对植物的生长影响以及植物对矿化垃圾混配种植介质中营养成分的吸收和重金属的富集,将矿化垃圾和本地绿化土按照不同比例混配,研究混配种植介质的理化性质的改善条件、矿化垃圾对植物体内的生物量和叶绿素含量的影响、植物对混配种植介质中营养成分的吸收量以及植物体内各种重金属累积浓度,探索矿化垃圾的最佳施用比例.实验结果表明,矿化垃圾可改善上海本地土壤贫瘠的普遍状况,其添加质量分数在50%~75%合适,对植物生长有利.  相似文献   
68.
69.
Self‐determination theory suggests that some rewards can undermine autonomous motivation and related positive outcomes. Key to this undermining is the extent to which rewards are perceived as salient in a given situation; when this is the case, individuals tend to attribute their behavior to the incentive, and the intrinsic value of the task is undermined. The role of salience has yet to be explicitly tested with respect to work motivation; we know little about whether undermining occurs in relation to verbal rewards, which characterize everyday work. We examine this in a field‐based quantitative diary study of 58 employees reporting 287 critical incidents of motivated behavior. When considering simple direct effects, the undermining effect was not supported; highly salient verbal rewards associated positively with introjected and external motivation, but at no cost to autonomous motivation. However, moderator analysis found support for the undermining effect for complex tasks; highly salient verbal rewards associated positively with external motivation while associating negatively with intrinsic and identified motivation. The findings suggest that verbal reward salience is an important characteristic of verbal reward perceptions and that salient verbal rewards are not advisable for more complex tasks but can have a valuable motivational impact for simple tasks. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
70.
Objective: Despite advances in vehicle safety systems, motor vehicle crashes continue to cause ankle fractures. This study attempts to provide insight into the mechanisms of injury and to identify the at-risk population groups.

Methods: A study was made of ankle fractures patients treated at an urban level 1 trauma center following motor vehicle crashes, with a concurrent analysis of a nationally representative crash data set. The national data set focused on ankle fractures in drivers involved in frontal crashes. Statistical analysis was applied to the national data set to identify factors associated with fracture risk.

Results: Malleolar fractures occurred most frequently in the driver's right foot due to pedal interaction. The majority of complex/open fractures occurred in the left foot due to interaction with the vehicle floor. These fractures occurred in association with a femoral fracture, but their broad injury pattern suggests a range of fracture causation mechanisms. The statistical analysis indicated that the risk of fracture increased with increasing driver body mass index (BMI) and age.

Conclusions: Efforts to reduce the risk of driver ankle injury should focus on right foot and pedal interaction. The range of injury patterns identified here suggest that efforts to minimize driver ankle fracture risk will likely need to consider injury tolerances for flexion, pronation/supination, and axial loading in order to capture the full range of injury mechanisms. In the clinical environment, physicians examining drivers after a frontal crash should consider those who are older or obese or who have severe femoral injury without concurrent head injury as highly suspicious for an ankle injury.  相似文献   

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