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471.
In recent years, there has been increasing interest in positive organizational scholarship in general, including positive organizational behavior (POB) in particular. This work identifies organizational citizenship behavior (OCB) as a prototypical POB. Conceptualizing OCBs in this way is sensible in light of more than 30 years of research highlighting the desirable aspects of such behavior. At the same time, some researchers have raised questions about positive organizational scholarship and have called for a more balanced view of ostensibly positive behaviors. The purpose of this paper, then, is to take a more nuanced view of OCBs while highlighting the dark side of citizenship behavior. In doing so, we review conceptual and empirical work that has challenged the idea that OCBs are inherently positive. We also discuss research that seeks to develop a deeper understanding of the conditions under which OCB does more harm than good. Finally, important areas for future research and the practical realities facing scholars who seek to publish research investigating the dark side of citizenship are addressed as well. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
472.
473.
文章对大功率电磁加热系统的电磁兼容性进行了分析,针对系统中的主要电磁干扰源,从传导干扰以及辐射干扰的角度对这些干扰的产生机理进行了分析。从电路布局设计、屏蔽技术两个方面提出了一系列抑制干扰的方法与原则。可为大功率电磁加热系统的设计提供参考。 相似文献
474.
通过氧指数、质量损失率及路用性能试验,研究EC130温拌剂、FRMAX型阻燃剂对沥青混合料阻燃效果的影响。试验结果显示,相比普通沥青混合料,阻燃沥青混合料、温拌阻燃沥青混合料氧指数分别增加23.3%、25.6%,质量损失率减小28.0%、32.0%,残留动稳定度增加14.0%、16.1%,残留最大弯拉应变增加14.1%、17.1%,冻融劈裂强度比增加5.3%、9.0%。相比普通沥青路面,阻燃沥青路面、温拌阻燃沥青路面发生火灾时能够减少34.0%、41.1%的毒害气体生成,并减少路面修补所需的混合料质量。其次得出普通沥青路面、阻燃沥青路面及温拌阻燃沥青路面的质量损失率、残留动稳定度、残留最大弯拉应变、残留冻融劈裂强度比与燃烧时间的关系模型。结果表明:阻燃剂对沥青混合料的阻燃效果显著;温拌剂有助于阻燃剂更好地发挥阻燃作用,降低火灾对道路的破坏,降低隧道火灾发生时有害气体的生成,提升隧道安全性。 相似文献
475.
476.
封育保护是促进退化草地自然恢复的有效方法之一,为了研究实施京津风沙源工程措施以来浑善达克沙地沙质草场的围封效果,我们特对浑善达克沙地南缘地段的围封草场进行了调查,并取得了一些结果。 相似文献
477.
随着西部大开发的脚步,北方地区焦化行业的日渐壮大,很多小焦化企业纷纷关停,取而代之的是大规模的焦化企业。大规模焦化企业的发展可以以新带老,改善超标排放的现状,对保护当地环境起到积极作用,对焦化行业的规范运行也是个好的开始。然而不管规模如何壮大,焦化行业始终面临的一个严峻的问题就是污水排放问题。以前老套的污水处理难度大,效果差。现在出现了一种新的焦化废水处理工艺-污水焚烧技术。它作为处理焦化废水的另一种方法,其效果与可行性很具有研究价值。 相似文献
478.
利用鞍山市空气污染源排放清单和ADMS——城市模型,从不同类型、不同高度两个角度分析了鞍山市区及周边的污染源(包括清单污染源和非清单污染源)对市区空气中尘污染的影响,并初步分析了背景及外来尘、各尾矿库及排岩场扬尘和市区二次扬尘产生量及对市区空气质量的影响,并提出了尘污染的解决重点。 相似文献
479.
Allelopathic inhibition on red tide microalgae Skeletonema costatum by five macroalgal extracts 总被引:1,自引:0,他引:1
Zhen An Zhenyu Wang Fengmin Li Zhijia Tian Hongying Hu 《Frontiers of Environmental Science & Engineering in China》2008,2(3):297-305
This study aims to identify effective antialgal allelochemicals from marine macroalgae that inhibit the growth of red tide
microalgae. Practically, new algicidal agents were developed to control red tide. The growth inhibitory effects of 5 marine
macroalgae Porphyra tenera, Laminaria japonica, Ulva pertusa, Enteromorpha clathrata, and Undaria pinnatifida on Skeletonema costatum were evaluated by adding crude seawater extracts of macroalgal dry tissue into the culture medium containing S. costatum. The half-effective concentrations at 120 h (EC50, 120 h) of the seawater extracts were 0.6, 0.9, 1.0, 1.0, and 4.7 g/L for the five macroalgae above, respectively. E. clathrata, L. japonica and U. pertusa showed strong allelopathic effect on the growth of S. costatum. There have been no previous reports with regard to the allelopathic effects of the former two macroalgae so far. The possible
allelochemicals of 21 compounds of the E. clathrata were detected using Gas chromatography-mass spectrometry (GC-MS) analysis. Unsaturated fatty acids, acrylic acid (C3H4O2), and linolenic acid (C18H30O2) were the most likely allelochemicals in E. clathrata. 相似文献
480.
Michael H. Huesemann Joyce A. Huesemann 《Environment, Development and Sustainability》2008,10(6):787-825
Industrial society will move towards collapse if its total environmental impact (I), expressed either in terms of energy and
materials use or in terms of pollution, increases with time, i.e., dI/dt > 0. The traditional interpretation of the I = PAT
equation reflects the optimistic belief that technological innovation, particularly improvements in eco-efficiency, will significantly
reduce the technology (T) factor, and thereby result in a corresponding decline in impact (I). Unfortunately, this interpretation
of the I = PAT equation ignores the effects of technological change on the other two factors: population (P) and per capita
affluence (A). A more heuristic formulation of this equation is I = P(T)·A(T)·T in which the dependence of P and A on T is
apparent. From historical evidence, it is clear that technological revolutions (tool-making, agricultural, and industrial)
have been the primary driving forces behind successive population explosions, and that modern communication and transportation
technologies have been employed to transform a large proportion of the world’s inhabitants into consumers of material- and
energy-intensive products and services. In addition, factor analysis from neoclassical growth theory and the rebound effect
provide evidence that science and technology have played a key role in contributing to rising living standards. While technological
change has thus contributed to significant increases in both P and A, it has at the same time brought about considerable eco-efficiency
improvements. Unfortunately, reductions in the T-factor have generally not been sufficiently rapid to compensate for the simultaneous
increases in both P and A. As a result, total impact, in terms of energy production, mineral extraction, land-use and CO2 emissions, has in most cases increased with time, indicating that industrial society is nevertheless moving towards collapse.
The belief that continued and even accelerated scientific research and technological innovation will automatically result
in sustainability and avert collapse is at best mistaken. Innovations in science and technology will be necessary but alone
will be insufficient for sustainability. Consequently, what is most needed are specific policies designed to decrease total
impact, such as (a) halting population growth via effective population stabilization plans and better access to birth control
methods, (b) reducing total matter-energy throughput and pollution by removing perverse subsidies, imposing regulations that
limit waste discharges and the depletion of non-renewable resources, and implementing ecological tax reform, and (c) moving
towards a steady-state economy in which per-capita affluence is stabilized at lower levels by replacing wasteful conspicuous
material consumption with social alternatives known to enhance subjective well-being. While science and technology must play
an important role in the implementation of these policies, none will be enacted without a fundamental change in society’s
dominant values of growth and exploitation. Thus, value change is the most important prerequisite for avoiding global collapse.
相似文献
Michael H. HuesemannEmail: |