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101.
The authors conducted an experiment to show how the interplay between informational diversity and other dimensions of diversity can account for some of the inconsistent effects of informational diversity in previous research. A total of 70 four-person groups involved in a decision-making task received homogeneous or heterogeneous information. By manipulating gender composition and bogus personality feedback, the authors created groups that were heterogeneous (i.e., had a strong basis for subgroup categorization) or were homogeneous on these dimensions. In diverse groups characterized by a diversity faultline, heterogeneity of information either converged with or cross-cut the faultline. Results showed that informational diversity enhanced group functioning when it was crossed rather than converged with the existing faultline, which became manifest in increased information elaboration, higher satisfaction, reduced relationship and task conflict, and a better team climate. Extending previous work, these findings show that informational diversity may have positive effects on team functioning even when teams are not homogeneous on other diversity dimensions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
In the present research, the authors examined the effect of procedural fairness and rewarding leadership style on an important variable for employees: self-esteem. The authors predicted that procedural fairness would positively influence people's reported self-esteem if the leader adopted a style of rewarding behavior for a job well done. Results from a scenario experiment, a laboratory experiment, and an organizational survey indeed show that procedural fairness and rewarding leadership style interacted to influence followers' self-esteem, such that the positive relationship between procedural fairness and self-esteem was more pronounced when the leadership style was high in rewarding behavior. Implications in terms of integrating the leadership and procedural fairness literature are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
104.
The prospect of extending natural biological design to develop new synthetic ceramic–metal composite materials is examined. Using ice-templating of ceramic suspensions and subsequent metal infiltration, we demonstrate that the concept of ordered hierarchical design can be applied to create fine-scale laminated ceramic–metal (bulk) composites that are inexpensive, lightweight and display exceptional damage-tolerance properties. Specifically, Al2O3/Al–Si laminates with ceramic contents up to approximately 40 vol% and with lamellae thicknesses down to 10 µm were processed and characterized. These structures achieve an excellent fracture toughness of 40 MPa√m at a tensile strength of approximately 300 MPa. Salient toughening mechanisms are described together with further toughening strategies.  相似文献   
105.
Power electronics' polluting effects   总被引:2,自引:0,他引:2  
In use far and wide for improved delivery and control of the electricity supply, power electronics systems are both the cause and remedy of the power system harmonic pollution problem. Here, the authors describe how an insidious side-effect of any solution involving power electronics converters is their generation of high-frequency pollution-namely, conducted and radiated noise in the 100 kHz to 100 MHz range-which can have an adverse effect on the operation of surrounding electronic equipment. Solutions to this problem are also offered in this paper  相似文献   
106.
Long‐chain internal olefins were prepared by silver(II)‐catalyzed oxidative decarboxylation of unsaturated fatty acids by sodium peroxydisulfate. Similar to saturated carboxylic acids, 1‐alkenes were the major decarboxylation product in the additional presence of copper(II), whereas in the absence of copper(II) alkanes were predominantly formed. In both cases, the internal unsaturation of the fatty acids remained largely intact, although the moderate yields indicated that side reactions occurred to a significant extent. The simple procedure makes this multistep one‐pot reaction useful for the synthesis of a variety of internally unsaturated hydrocarbons. The purified products, almost all of which are prepared for the first time, may serve as reference compounds for studies on the heterogeneously catalyzed decarboxylation of triglycerides and fatty acids in the absence of hydrogen. Practical applications: The products of the chemistry described in this contribution, i.e., unsaturated long‐chain hydrocarbons, provide bio‐based building blocks for further chemical modification toward products which may be applied as (bio)fuels, lubricants, solvents, and polymeric materials.  相似文献   
107.
Because of the large flexibility and malleability of Cytochrome P450 enzymes (CYPs), in silico prediction of CYP binding affinities to drugs and other xenobiotic compounds is a true challenge. In the current work, we use an iterative linear interaction energy (LIE) approach to compute CYP binding affinities from molecular dynamics (MD) simulation. In order to improve sampling of conformational space, we combine results from simulations starting with different relevant protein-ligand geometries. For calculated binding free energies of a set of thiourea compounds binding to the flexible CYP 2D6 isoform, improved correlation with experiment was obtained by combining results ofMDruns starting from distinct protein conformations and ligand-binding orientations. This accuracy was obtained from relatively short MD simulations, which makes our approach computationally attractive for automated calculations of ligand-binding affinities to flexible proteins such as CYPs.  相似文献   
108.
简要介绍了波与振动的关系,超声波的分类,超声波的传播特性与声场特征量。同时介绍了超声波换能器(探头)及其等效电路。  相似文献   
109.
Extracellular vesicles (EVs) are emerging as important mediators of cell–cell communication as well as potential disease biomarkers and drug delivery vehicles. However, the mechanical properties of these vesicles are largely unknown, and processes leading to microvesicle‐shedding from the plasma membrane are not well understood. Here an in depth atomic force microscopy force spectroscopy study of the mechanical properties of natural EVs is presented. It is found that several natural vesicles of different origin have a different composition of lipids and proteins, but similar mechanical properties. However, vesicles generated by red blood cells (RBC) at different temperatures/incubation times are different mechanically. Quantifying the lipid content of EVs reveals that their stiffness decreases with the increase in their protein/lipid ratio. Further, by maintaining RBC at “extreme” nonphysiological conditions, the cells are pushed to utilize different vesicle generation pathways. It is found that RBCs can generate protein‐rich soft vesicles, possibly driven by protein aggregation, and low membrane–protein content stiff vesicles, likely driven by cytoskeleton‐induced buckling. Since similar cortical cytoskeleton to that of the RBC exists on the membranes of most mammalian cells, our findings help advancing the understanding of the fundamental process of vesicle generation.  相似文献   
110.
以北京世纪华扬能源科技有限公司在中海油渤海海底原油管道上安装的ASI音波测漏系统为例,介绍该音波测漏系统在海底管道应用的工作原理、硬件架构组成、测试验收方法。  相似文献   
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