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751.
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V. L. Finkenstadt C.-K. Liu P. H. Cooke L. S. Liu J. L. Willett 《Journal of Polymers and the Environment》2008,16(1):19-26
Sorbitol and glycerol were used to plasticize sugar beet pulp-poly(lactic acid) green composites. The plasticizer was incorporated
into sugar beet pulp (SBP) at 0%, 10%, 20%, 30% and 40% w/w at low temperature and shear and then compounded with poly(lactic
acid) (PLA) using twin-screw extrusion and injection molding. The SBP:PLA ratio was maintained at 30:70. As expected, tensile
strength decreased by 25% and the elongation increased. Acoustic emission (AE) showed correlated debonding and fracture mechanisms
for up to 20% w/w plasticizer and uncorrelated debonding and fracture for 30–40% sorbitol and 30% glycerol content in SBP–PLA
composites. All samples had a well dispersed SBP phase with some aggregation in the PLA matrix. However, at 40% glycerol plasticized
SBP–PLA composites exhibited unique AE behavior and confocal microscopy revealed the plasticized SBP and PLA formed a co-continuous
two phase system.
相似文献
V. L. FinkenstadtEmail: |
754.
基于Berthollet反应示波极谱法测定水中微量氨 总被引:1,自引:0,他引:1
在亚硝基铁氰化钾存在下,氨在氢氧化钠介质中与苯酚、次氯酸钠反应,其产物靛酚在滴汞电极上产生-灵敏的吸附波,NH3-N在0.003~0.22mg/L内,导数峰电流与其呈良好的线性关系。用于环境水中NH3-N的测定,其相对标准偏差小于3%,回收率为97%~105%,方法具有较好的选择性。 相似文献
755.
大气光化学烟雾反应机理比较(Ⅰ)O3和NOx的比较 总被引:8,自引:0,他引:8
在相同初始和排放条件下,对四种应用较广的光化学烟雾反应机理(CB4-99,RADM2,RACM,SAPRC99)进行了比较.研究发现对于O3,在低VOCs/NOx时,四种机理模拟结果相关较小,平均相对标准偏差为7%,在高VOCs/NOx时,平均相对标准偏差为26%,差距较大;对于NOx,多数情况下RACM和RADM2的模拟结果较高,CB4-99和SAPRC99的模拟值偏低,其原因主要来源于不同机理中O3的生成对NOx及VOCs的敏感性不同而造成的.在用模式模拟O3和NOx时,应特别注意机理不同而带来的模拟结果差异. 相似文献
756.
757.
硅酸盐细菌解钾兼拮抗活性菌株的筛选 总被引:13,自引:0,他引:13
从紫色土壤中分离筛选出具有解钾拮抗双重活性的硅酸盐细菌CS1和CS29菌株。接菌处理,其水溶性钾分别增加75%和65%,转化率达0.82%和0.72%。两株菌对革兰氏阳性的蜡样芽孢杆菌,金黄色葡萄球菌,藤黄八叠球菌等和革兰氏阴性的大肠杆菌均有较强的抑菌活性。筛选菌株中91.2%具有解钾活性,但拮抗活性菌株只占总数的11.6%,表明二性状之间无相关关系。表4参7 相似文献
758.
聚苯乙烯基硫代磺酸钾树脂的合成及其与卤代烃的反应 总被引:2,自引:2,他引:0
由聚苯乙烯基磺酰氯树脂与硫化氢钾反应制备聚苯乙烯基硫代磺酸钾树脂(I),树脂I与亲电的卤代烃反应,生成聚苯乙烯基硫代磺酸酯树脂(Ⅱ),树脂Ⅱ经过乙硫醇处理,使卤代烃结构部分以不对称二硫醚的形式游离下来,用GC/MS对其结构进行鉴定。从不对称二硫醚的结构可推导出原卤代烃的结构,所制备的聚苯乙烯基硫代磺酸钾树脂的转化效率为1.11mmol·g^-1。 相似文献
759.
Yuemin Yue Kelin Wang Bing Zhang Zhengchao Chen Quanjun Jiao Bo Liu Hongsong Chen 《Environmental monitoring and assessment》2010,160(1-4):157-168
Remote sensing of local environmental conditions is not accessible if substrates are covered with vegetation. This study explored the relationship between vegetation spectra and karst eco-geo-environmental conditions. Hyperspectral remote sensing techniques showed that there were significant differences between spectral features of vegetation mainly distributed in karst and non-karst regions, and combination of 1,300- to 2,500-nm reflectance and 400- to 680-nm first-derivative spectra could delineate karst and non-karst vegetation groups. Canonical correspondence analysis (CCA) successfully assessed to what extent the variation of vegetation spectral features can be explained by associated eco-geo-environmental variables, and it was found that soil moisture and calcium carbonate contents had the most significant effects on vegetation spectral features in karst region. Our study indicates that vegetation spectra is tightly linked to eco-geo-environmental conditions and CCA is an effective means of studying the relationship between vegetation spectral features and eco-geo-environmental variables. Employing a combination of spectral and spatial analysis, it is anticipated that hyperspectral imagery can be used in interpreting or mapping eco-geo-environmental conditions covered with vegetation in karst region. 相似文献
760.
Lidong Xue Yinhai Lang Aixia Liu Jie Liu 《Environmental monitoring and assessment》2010,163(1-4):57-65
Polycyclic aromatic hydrocarbons (PAHs) in coastal surface sediments from Rizhao offshore area were analyzed by gas chromatography–mass spectrometry. A chemical mass balance (CMB) model developed by the U.S. Environmental Protection Agency (EPA), CMB8.2, was used to apportion sources of PAHs. Seven possible sources, including coal residential, coal power plant, diesel engines exhaust, gasoline engines exhaust, coke oven, diesel oil leaks, and wood burning, were chosen as the major contributors for PAHs in coastal surface sediments. To establish the fingerprints of the seven sources, source profiles were collected from literatures. After including degradation factors, the modified model results indicate that diesel oil leaks, diesel engines exhaust, and coal burning were the three major sources of PAHs. The source contributions estimated by the EPA’s CMB8.2 model were 9.25%, 15.05%, and 75.70% for diesel oil leaks, diesel engines exhaust, and coal burning, respectively. 相似文献