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11.
RRN Sailaja 《Polymer International》2005,54(12):1589-1598
Lignin was graft copolymerized with methyl methacrylate using manganic pyrophosphate as initiator. This modified lignin was then blended (up to 50 wt%) with low density polyethylene (LDPE) using a small quantity of poly[ethylene‐co‐(glycidyl methacrylate)] (PEGMA) compatibilizer. The mechanical properties of the blend were substantially improved by using modified lignin in contrast to untreated lignin. Differential scanning calorimetry studies showed loss of crystallinity of the LDPE phase owing to the interaction between the blend components. Thermogravimetric analysis showed higher thermal stability of modified lignin in the domain of blend processing. This suggested that there is scope for useful utilization of lignin, which could also lead to the development of eco‐friendly products. Copyright © 2005 Society of Chemical Industry 相似文献
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Yun‐Hwei Shen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(5):581-586
A novel strategy of sweep coagulation to treat low turbidity water is presented herein. Study findings demonstrated that an Na+‐saturated bentonite with medium cation exchange capacity (CEC) resulted in significant turbidity removal at a bentonite dosage of 30 mg dm?3. Bentonite dispersion with fully delaminated platelets tended to undergo a more porous type of coagulation with intense face‐to‐face interactions of platelets and effectively entrapped TiO2 particles in band‐type structures. This type of coagulation usually results in a large volume of settled flocs with a fluffy structure and excellent turbidity removal efficiency for sweep coagulation. The sign and magnitude of electrical charge on TiO2 particles has a minor effect on the efficiency of sweep coagulation. Copyright © 2005 Society of Chemical Industry 相似文献
14.
Kahler Christopher W.; Read Jennifer P.; Wood Mark D.; Palfai Tibor P. 《Canadian Metallurgical Quarterly》2003,17(3):226
Structural equation modeling was used to test the mediational role of social environmental selection on alcohol use in cross-sectional samples of 447 students from a rural state university and 421 students from an urban private university. Results showed that male gender, White ethnicity, and sensation seeking were uniquely associated with greater alcohol use. Mediational analyses indicated that socioenvironmental factors (i.e., Greek involvement, friends' approval of drinking/getting drunk) were positively associated with alcohol use and significantly accounted for parts of the effects of ethnicity and sensation seeking, but not gender, on alcohol use. Results suggest that White students and those high on sensation seeking may drink more heavily in college, in part because they select social environments in which alcohol use is encouraged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
柴油机低频排气噪声规律分析 总被引:4,自引:0,他引:4
针对柴油机(4-85)低频排气噪声,对其产生机理、规律及其影响因素等作了理论计算、分析及实验。对低频排气噪声信号进行频域分析后可知,其主要由一系列离散的谐波组成,是以柴油机点火频率为基频的一种类周期性噪声,有可能应用有源噪声控制技术。 相似文献
16.
The causes of lightning outage are subdivided into direct lightning strokes and induced lightning strokes, which are identified by the characteristics of the lightning overvoltage. In the past, lightning protection devices were directed mainly toward the latter, and attention has been focused on the installation of lightning protection devices, ground wires, and reinforcement of insulators. However, lightning outages continue to occur. Thus it is extremely important to clarify the fault characteristics of lightning surges and to study the effectiveness of various lightning protection devices by considering both direct lightning stroke and induced lightning stroke in order to prevent lightning outage in the future. In this research, the electromagnetic transients program (EMTP) has been applied to the direct lightning stroke, and the induced lightning outage analysis program for multiple conductor systems has been applied to the induced lightning stroke to study the effectiveness of lightning protection devices provided by combination of various lightning protection devices. The most effective lightning protection schemes are analyzed and evaluated based on verification tests on the full scale models as well as economic considerations. 相似文献
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小高层建筑需通过剪力墙开洞(结构开洞)降低侧向刚度,本文对开洞部位以及墙肢和连梁设计提出一些看法,供设计人员参考。 相似文献
19.
低熔封接玻璃组成及其发展 总被引:25,自引:2,他引:23
综述了低熔封接玻璃的组成特点,给出了大量低熔玻璃组成实例,批出了低熔封接玻璃的封接低温化和无铅化发展方向,磷酸盐玻璃是首选组成之一。新的制备工艺和新的玻璃形成体系将对封接玻璃发展起着十分重要的作用。 相似文献
20.
农业重组微生物生物安全研究进展 总被引:2,自引:2,他引:0
综述了近年来农业重组微生物的研究现状和进展 ,详细介绍农业重组微生物环境释放的监控方法以及对环境的冲击作用 ,对一些有关生物安全研究的热点问题进行了探讨 相似文献