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761.
Liang Chen Syed H. Imam Sherald H. Gordon Richard V. Greene 《Journal of Polymers and the Environment》1997,5(2):111-117
Starch-PVOH cast films were prepared with and without crosslinking agent (hexamethoxymethylmelamine) in the absence of plasticizer.
Moisture absorption in films without crosslinking agent at a low relative humidity was similar to that of PVOH and increased
as the relative humidity increased. Films with crosslinking agent showed moisture absorption linearly proportional to the
relative humidity. Significant improvement in resistance to water disintegration for crosslinked starch-PVOH films was observed.
While the tensile strength decreased with increased relative humidity, crosslinking significantly improved the tensile strength.
Increased PVOH content improved elongation of films even when the relative humidity was 80% or higher. Biodegradation studies
revealed that the degradation rate was negatively correlated with the PVOH content in films and crosslinking generated more
converged degradation curves.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
762.
Car manufacturers must eliminate automotive shredder residues (ASR). Two ways of incineration are of interest: at 850°C in municipal waste incinerators or at higher temperatures, above 1100°C in cement plants. These processes reduce the mass and the volume of waste to be disposed of in landfills and energy recovery might be possible. Regulations govern the emission of gaseous effluents to control environmental risk. To determine gaseous effluents from a pilot sacle or an industrial incineration plant, an artificial ASR was made by mixing three representative organic polymers present in the real ASR, namely polyvinylchloride, polyurethane and rubber. This mixture was incinerated at 850 and 1100°C in laboratory experiments and the analyses of the principal gaseous effluents such as carbon oxides, nitrogen oxides, volatile organic compounds, hydrochloric and hydrocyanic acids and sulphur compounds are presented and discussed. Lastly, in order to simulate artificial ASR behaviour, the composition of the combustion gases at equilibrium was calculated using a Gibbs energy minimisation code. 相似文献
763.
Activated carbon, developed from fertilizer waste, has been used for the removal of Hg2+, Cr6+, Pb2+, and Cu2+. Mass transfer kinetic approach has been successfully applied for the determination of various parameters necessary for designing a fixed-bed absorber. Parameters selected are the length of the (PAZ) primary adsorption zone (δ), total time involved for the establishment of primary adsorption zone (tx), mass rate of flow to the absorber (Fm), time for primary adsorption zone to move down its length (tδ), amount of adsorbate adsorbed in PAZ from breakpoint to exhaustion (Ms), fractional capacity (f), time of initial formation of PAZ (tf) and per cent saturation of column at break point. Chemical regeneration has been achieved with 1 M HNO3. 相似文献
764.
Groundwater was being remediated with pump and treat technology at a facility where the groundwater was contaminated with commonly used degreaser solvents. Hydraulic conductivity of the heterogeneous residuum was beneficiated by applying pneumatic fracturing technology. The remedial system was controlled and monitored by a sophisticated remote telemetry system. A case history follows. 相似文献
765.
基于神经网络的重大危险源动态分级研究 总被引:8,自引:2,他引:8
利用自组织神经网络对重大危险源进行动态分级研究,介绍了神经网络的模式聚类即分级法的自组织学习过程和算法,克服了以往危险源分级方法的某些局限性。在计算机上进行的模拟计算表明:基于自组织神经网络的重大危险源动态分级方法是合理可行的 相似文献
766.
通过对安全投资与事故经济损失的规律性的分析研究,确立安全投资与经济效益的内在关系,进一步探索在我国现有财力和安全水平的基础上,找准安全投资的投向,优化安全投资的合理分配,从而实现最大限度地提高企业安全生产水平和安全投资效益。为政府部门或企业提供一套经过优化、科学合理、操作性又比较强的安全投资方案,供各级领导进行安全决策,实现本部门、本单位的安全投资计划时参考 相似文献
767.
王甫洲水利枢纽工程泄水闸施工围堰基础主要为砂卵石层,结构中密~密实,属较强~极强透水层。使用改制的BZK—3A 型喷灌机,大水量、大浆量、不分序连续施工,高压定喷构筑围堰基础防渗板墙。经围井开挖检查,钻孔及围井挖后抽水试验、泄水闸基坑开挖后的防渗效果分析表明,高喷防渗板墙厚度、墙体强度及墙体渗透系数均满足设计要求 相似文献
768.
防辐射有机玻璃板材的抗辐射性能 总被引:7,自引:0,他引:7
系统研究了含铅有机玻璃、含钡有机玻璃、含硼有机玻璃和普通有机玻璃的x、γ射线和中子射线防护性能及其耐60Cγ射线辐照稳定性。结果表明,含铅有机玻璃板材具有良好的x射线、反应堆热柱γ射线屏蔽性能;合硼有机玻璃板材具有良好的热中子屏蔽性能;含钡有机玻璃板材的褪化裂变谱中子辐射屏蔽性能良好;含钡有机玻璃和普通有机玻璃可耐105~106Gy的60Coy射线辐照;含铅有机玻璃板材耐60Coy射线照射能力小于105Gy。 相似文献
769.
Timothy D. Golden 《组织行为杂志》2006,27(3):319-340
Relationships are fundamental to organizational functioning, yet as telecommuting and other forms of virtual work become increasingly popular, research has not yet focused on how the virtual context might alter relationships so as to impact important work outcomes. This study therefore examines the role relationships play in mediating the link between the extent of telecommuting and job satisfaction. In doing so three fundamental types of relationships maintained by employees are investigated—those with managers, coworkers, and family. Regression analysis of field data from 294 telecommuting employees in a large telecommunications company revealed the anticipated inverted U‐shaped relationship, mediated by leader‐member exchange quality, team‐member exchange quality, and work‐family conflict. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
770.
This study examined the relationships between culture, individual attributes, and self‐rating behavior among 1,786 university students in Canada, Hong Kong, Taiwan, mainland China, and Japan, and in doing so extended and refined the cultural relativity hypothesis. It explored the difference between vertical and horizontal individualists in self‐rating behavior, and examined the mediating effects of two individual attributes, self‐enhancement propensity and general self‐efficacy in the relationship between individualism and self‐rating behavior. The results confirmed that individualism is the cultural driver for self‐rating leniency, and that the individual‐level assessment of individualism is a stronger predictor of self‐rating leniency than are culture‐level differences. Vertical individualism was found to be positively related to self‐enhancement propensity, which in turn was positively related to self‐rating. Whereas, horizontal individualism was positively related to general self‐efficacy, which in turn had a positive relationship with self‐rating. We discuss the implications of the results for academic research and practical management. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献