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991.
This study examined antecedents and outcomes of a fourfold taxonomy of work-family balance in terms of the direction of influence (work-family vs. family-work) and type of effect (conflict vs. facilitation). Respondents were full-time employed parents in India. Confirmatory factor analysis results provided evidence for the discriminant validity of M. R. Frone's (2003) fourfold taxonomy of work-family balance. Results of moderated regression analysis revealed that different processes underlie the conflict and facilitation components. Furthermore, gender had only a limited moderating influence on the relationships between the antecedents and the components of work-family balance. Last, work-family facilitation was related to the work outcomes of job satisfaction and organizational commitment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Interpolymer complex formations between Form II helical poly(l-proline) [PLP(II)] and Form I helical poly(l-proline) [PLP(I)] and poly(carboxylic acids) such as polyacrylic acid (PAA), atatic polymethacrylic acid (at-PMAA), and syndiotatic
polymethacrylic acid (st-PMAA) have been studied by FT-IR, X-ray diffraction, and light scattering measurements. It was found
that the interpolymer complexes were formed via hydrogen bonding. The helical PLP(II) formed polymer complex more favorably with PAA and at-PMAA having a disordered structure
than with st-PMAA having a ordered structure. In contrast, the helical PLP(I) formed polymer complex more favorably with st-PMAA
than with PAA and at-PMAA. In addition, PLP(II) helix was destroyed on the complexation with PAA and at-PMAA, but the PLP(II)
helix was perserved on the complexation with st-PMAA. However, the PLP(I) helix was all perserved on the complexation with
poly(carboxylic acids). These findings could be explained in terms of molecular conformation of the complementary polymers
associated with the complex formation.
Received: 4 March 1997/Revised: 21 April 1997/Accepted: 28 April 1997 相似文献
993.
Hee-Tak Kim Dae Jong You Hae-Kwon Yoon Sang Hoon Joo Chanho Pak Hyuk Chang In-Seob Song 《Journal of power sources》2008,180(2):724-732
The development of a cathode catalyst layer based on a supported Pt catalyst using an ordered mesoporous carbon (OMC) for direct methanol fuel cell is reported. An OMC with a mesopore structure between hexagonally arranged carbon nanorods is prepared using a template method. Platinum nanoparticles are supported on the OMC (Pt/OMC) with high metal loading of 60 wt.%. Compositional and morphological variations are made by varying the ionomer content and by compressing the catalyst layer to detect a parameter that determines the power performance. Increase in power density with decrease in the volume fraction of ionomer in the agglomerate comprising the Pt/OMC and the ionomer indicates that mass transport through the ionomer phase governs the kinetics of oxygen reduction. Impedance spectroscopic analysis suggests that a significant mass-transport limitation occurs at high ionomer content and in the compressed cathode. The power density of the optimum cathode layer, which employs a Pt/OMC catalyst with a Pt loading of 2 mg cm−2, is greater than that of a catalyst layer with 6 mg cm−2 Pt-black catalyst at a voltage higher than 0.4 V. This would lead to a significant reduction in the cost of the membrane electrode assembly. 相似文献
994.
Formation of the adiabatic shear band in sheet metal is investigated with experiments for high strength steel sheets, 60 C
and 60 TRIP. Since the adiabatic shear band is formed as a result of adiabatic shear failure with a narrow band of concentrated
shear strain, the adiabatic shear band plays an important role in the analysis of high speed deformation phenomena. For shear
band experiments with a tension split Hopkinson bar, specimens are designed to induced large shear strain. The experimental
results show that the shear deformation modes of two sheet metals, 60 TRIP and 60 C, are quite different from each other in
that the adiabatic shear band is observed only in 60 C. The shear deformation in 60 TRIP is restrained by the abrupt increase
of strength due to the plastic strain, which interferes with propagation of the shear crack. Instead, a tensile crack developed
at the corner where the shear crack should have been initiated. As a result, the load-displacement curves show that the tensile
load of 60 TRIP specimens becomes higher than that of 60 C at the same displacement. 相似文献
995.
E. MacCormack A. Mandelis M. Munidasa B. Farahbakhsh H. Sang 《International Journal of Thermophysics》1997,18(1):221-250
The thermal diffusivity of various types of aluminum has been measured, using a completely noncontact experimental configuration
based on infrared photothermal radiometry. Photothermal response transients, conventional frequency scans, and pulse duration-
or repetition rate-scanned rate windows have been investigated. It has been shown that the conventional frequency scan is
not suitable for measurements of aluminum with a short thermal transport time such as foils, due to an extremely degraded
signal-to-noise ratio (SNR). Also, it has been found that the conventional frequency scan method is less sensitive to the
actual value of thermal diffusivity than the rate-window scan. The rate-window method, furthermore, gives superior SNR especially
for thin metals and yields excellent agreement between the theory and the data. An advantage of the pulse duration-scanned
rate window mode is that it does not require knowledge of the instrumental transfer function as an input. The transient response
gives the worst SNR but is best for the physical interpretation of the photothermal signals. In addition, it has been shown
that the infrared photothermal radiometric transmission mode is less sensitive to surface roughness than the reflection mode
and, therefore, is preferable for thermal diffusivity measurements of aluminum and of good thermal conductors, in general. 相似文献
996.
文章通过几个工程实例设计手法的分析,提出了几种经常在建筑创作中运用的非理性手法--变异、抽象、渗透、散漫、动态. 相似文献
997.
Sang‐Kyung Ahn Kyung‐Won Min Ji‐Hun Park Sang‐Hyun Lee Dong‐Guen Lee Jung‐Keun Oh Ki‐Soo Kim Sung‐Kyung Lee 《The Structural Design of Tall and Special Buildings》2008,17(1):231-243
The purpose of this study is to evaluate the performance of viscoelastic dampers (VEDs) practically used for enhancing the serviceability of a 46‐story reinforced concrete residential building structure. Considering that a bracing system for the installation of VEDs is not appropriate for a residential building because it occupies a large interior space, a method for installing VEDs at the midspan of a horizontal beam connecting the core and exterior columns is proposed. These VEDs control the total structural response in a similar way to a general outrigger system. The results from numerical analysis indicate that VEDs are effective for reducing not only mean components but also fluctuating ones of wind‐induced responses by providing additional damping as well as stiffness. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
998.
999.
The effect of diffusion on the pH and temperature profiles of immobilized enzymes has been quantitatively assessed using the theory of pore diffusion. The pH profiles of immobilized enzyme systems varied from those of soluble ones to the square root of the relative values of the soluble ones depending on the degree of pore diffusion limitation. Also the decrease in activation energy was predicted quantitatively with considerable accuracy in terms of effectiveness factor. The experimental pH profiles of a few immobilized enzymes were compared with those theoretically predicted. 相似文献
1000.
基于测井资料划分识别页岩气储层的方法有多种,但不同方法的适用性及其识别精度均有差别。因此,优选出页岩气储层的区域性识别方法具有重要意义。通过对四川盆地下志留统龙马溪组页岩气储层特征的综合分析比对,建立了页岩气储层与非储层的识别标准,深入剖析了重叠图法、?lgR识别法、总有机碳含量计算识别法的原理及适用性,并结合岩心分析资料对各方法进行评价、对比和精度分析,最终优选出常规测井资料组合法结合体积密度TOC指示法作为四川盆地龙马溪组页岩气储层的识别方法。结果表明:建立识别标准可为精确划分识别页岩气储层提供重要依据;自然伽马、密度及声波时差重叠曲线对页岩气储层的识别效果较好,而补偿中子由于受黏土影响较大而不适于作为该区的叠合曲线;孔隙度测井曲线重叠法识别非富有机质页岩气层的效果不佳;体积密度TOC指示法的划分成果能满足精度要求,而自然伽马TOC指示法识别精度相对较差。 相似文献