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21.
随着我国经济和社会的快速发展,人口和财富的密度越来越高,地震造成的损失也越来越严重。应用金融手段可以使地震风险与资本市场充分融合,缓解其给个人和社会造成的冲击。依据闽南地区4个重要城市的震害预测成果,讨论了如何应用地震保险和巨灾债券等金融手段减轻泉州海外未来大地震可能造成的损失。  相似文献   
22.
Moisture distributions in municipal sewage sludge, printing and dyeing sludge and paper mill sludge were experimentally studied based on four di erent methods, i.e., drying test, thermogravimetric-di erential thermal analysis (TG-DTA) test, thermogravimetricdi erential scanning calorimetry (TG-DSC) test and water activity test. The results indicated that the moistures in the mechanically dewatered sludges were interstitial water, surface water and bound water. The interstitial water accounted for more than 50% wet basis (wb) of the total moisture content. The bond strength of sludge moisture increased with decreasing moisture content, especially when the moisture content was lower than 50% wb. Furthermore, the comparison among the four di erent testing methods was presented. The drying test was advantaged by its ability to quantify free water, interstitial water, surface water and bound water; while TG-DSC test, TG-DTA test and water activity test were capable of determining the bond strength of moisture in sludge. It was found that the results from TG-DSC and TG-DTA test are more persuasive than water activity test.  相似文献   
23.
In this work, a series of novel proton-gradient-transfer acid complexes (PGTACs) were developed. Their physicochemical properties, including thermal stability, melting point, and Hammett acidity, were measured. The effects of catalyst loading, reaction temperature, and substrate expansion on the catalytic performance were systematically studied. It is found that the combination of bidentate N-heterocycle and H2SO4 (1:2 M ratio) could form simultaneously N–H covalent bond and N…H hydrogen bond, which makes the PGTACs excellent catalysts integrate the advantages of strong acids (high catalytic activity) and ionic liquids (phase separation) in the esterification reaction. Moreover, these PGTACs can be reused by convenient phase separation without obvious diminution of catalytic activity. It is concluded that these PGTACs are potential alternative candidates for esterification reaction in the process of industrial catalysis.  相似文献   
24.
The comparison of phenol sorption on phenyltrimethylammonium (PTMA)- and benzyltrimethylammonium (BTMA)-bentonite shows a clear difference as far as phenol sorption isotherms are concerned. For PTMA-bentonite the sorption isotherm is of a straight-line character which results from simple partitioning of phenol between the aqueous and organic phases sorbed on the bentonite surface. For BTMA-bentonite the isotherm has a convex shape, characteristic of physicochemical sorption.For the first time a three-parametric model, including the dissociation constant of phenol pKa, distribution constant of phenol Kdphen and phenolate anion Kdphen between the aqueous phase and the bentonite phases is used for the evaluation of phenol sorption on organoclays with pH change. The model shows that the values of Kdphen are higher than those of Kdphen for all investigated initial phenol concentrations.The inspection of the FTIR spectrum of BTMA-bentonite loaded with phenol in the regions 1300–1600 and 1620–1680 cm−1 shows the features of π–π electron interaction between the benzene rings of phenol and the BTMA cation together with the phenol–water hydrogen bond strengthened by this interaction.  相似文献   
25.
Biodegradation of methyl parathion by Acinetobacter radioresistens USTB-04   总被引:2,自引:0,他引:2  
Biodegradation of methyl parathion (MP),a widely used organophosphorus pesticide,was investigated using a newly isolated bacterium strain Acinetobacter radioresistens USTB-04.MP at an initial concentration of 1200 mg/L could be totally biodegraded by A.radioresistens USTB-04 as the sole carbon source less than 4 d in the presence of phosphate and urea as phosphorus and nitrogen sources,respectively.Biodegradation of MP was also achieved using cell-free extract of A.radioresistens USTB-04.MP at an initial concentration of 130 mg/L was completely biodegraded in 2 h in the presence of cell-free extract with a protein concentration of 148.0 mg/L,which was increased with the increase of pH from 5.0 to 8.0.Contrary to published reports,no intermediate or final degradation metabolites of MP could be observed.Thus we suggest that the cleavage of C--C bond on the benzene ring other than P-O bond may be the biodegradation pathway of MP by A.radioresistens USTB-04.  相似文献   
26.
有机修饰剂对土的离子交换修饰研究   总被引:2,自引:0,他引:2  
研究了有机修饰剂十六烷基三甲基溴化铵(CTMAB)对于塿土2层次土样修饰的离子交换机制.结果表明,土壤表面的CTMAB和Ca2 /2的总和(Scc)可以作为一个简便有效的指标用来判断修饰机制的实质,它的研究证实了CTMAB对于塿土2层次土样的修饰是离子交换修饰和疏水键修饰共存的机制.疏水键修饰机制开始出现于修饰比例20%~28?C范围内,并随修饰比例和CTMAB摩尔分数的增大而线性增大,但直到50?C修饰比例时疏水键修饰机制才显现出其对于土壤性质的影响,100?C左右修饰比例是疏水键修饰超过离子交换修饰而成为主要修饰机制的转折点. Vanselow离子选择性系数表明塿土土样对于CTMAB的吸附偏好要远远大于对Ca2 的吸附.热力学研究结果表明,随总浓度增加,在25%~100?C比例区间,修饰反应由放热、熵减反应转变为吸热熵增反应,而在100%~200?C区间,表观焓变和表观熵变表现出焓、熵趋于减小的趋势,总体上表现出由25%~100?C区间的熵变控制的自发性反应向100%~200?C区间的焓变控制的自发性过程转换的热力学特征,佐证了上述修饰机制的合理性.  相似文献   
27.
废旧电路板热解油合成酚醛树脂胶粘剂的研究   总被引:1,自引:0,他引:1  
研究了废旧电路板热解油代替苯酚合成酚醛树脂胶粘剂,采用L(93)4正交设计安排实验,重点考察了甲醛加入量、催化剂加入量,第一阶段反应温度和第二阶段反应温度四个因素对热解油酚醛树脂粘胶剂的胶合强度影响。依据正交试验结果和兼顾粘胶剂的整体性能,当热解油的加入量为35g时,合成酚醛树脂胶粘剂最优工艺为37wt%的甲醛加入量为47g,40wt%的氢氧化钠液加入量为7.8g,第一阶段温度为60℃,第二阶段温度为90℃。制得的酚醛树脂胶固含量,粘度和pH值适中,游离甲醛含量低于0.3wt%,符合GB/T14732-2006中规定的层压材料用酚醛树脂产品的相关标准和要求,并且其胶合强度符合GB/T9846-2004中由桦木制成的Ⅰ类胶合板胶合强度指标值(≥0.8MPa)。同时还对热解油和合成产物进行了高效液相色谱(HPLC),红外光谱分析(FTIR)分析,探求了反应变化的机理。由于废旧电路板热解油代替苯酚合成酚醛树脂胶粘剂降低了胶粘剂的生产成本,其所制得的胶粘剂有良好的应用前景。  相似文献   
28.
高强混凝土如今被广泛应用于各种重要的民用和工业建筑物上,与其维修加固相关的问题急需人们去研究、解决。目前,外贴玻璃纤维(GFRP)布加固高强混凝土的关键问题——界面的粘结破坏机理还很少有系统研究。本文对41个粘贴GFRP布的高强混凝土试件进行了单面剪切试验,得到了不同影响因素(混凝土强度、GFRP布粘结长度、宽度比、GFRP布刚度)作用下的界面剥离承载力、应变分布以及破坏模式。统计分析承载力试验值,给出了适合高强混凝土的宽度比系数,进而得到了GFRP布—高强混凝土界面的剥离承载力计算公式;进一步将试验值与陈-腾公式进行了比较,并且检验了已有承载力模型预测的准确性;由试验得到的应变数据考察了界面应变分布,发现应变的理论计算值与试验值在弹性阶段吻合较好。高强混凝土下,超过有效粘结长度后界面的破坏模式主要为界面剥离破坏。  相似文献   
29.
We analyze the stock market reaction to 161 major environmental and non-environmental accidents, reported on the front page of the New York Times for half a century. To determine if the market induces a real deterrence effect, we extend the event windows up to one year. On average, the market reacts negatively and enduringly to the announcement of an accident. However, this average effect is largely driven by the airline industry and by government interventions. The estimated average compounded abnormal return following environmental accidents does not differ from zero after one year. This does not exclude, in severe events affecting large firms, huge losses in equity value, but the significant negative cumulative abnormal returns estimated immediately after an environmental accident in previous studies do not persist. Our results suggest that in a market driven by institutional investors, the deterrence effect is likely to be weak.  相似文献   
30.
Various computational methods were employed to investigate the zwitterion formation,a critical step for the reaction of monoethanolamine with CO_2,in five solvents(water,monoethanolamine,propylamine,methanol and chloroform) to probe the effect of hydrogen bond capacity of solvents on the reaction of amine with CO_2 occurring in the amine-based CO_2 capture process.The results indicate that the zwitterion can be formed in all considered solvents except chloroform.For two pairs of solvents(methanol and monoethanolamine,propylamine and chloroform) with similar dielectric constant but different hydrogen bond capacity,the solvents with higher hydrogen bond capacity(monoethanolamine and propylamine) facilitate the zwitterion formation.More importantly,kinetics parameters such as activation free energy for the zwitterion formation are more relevant to the hydrogen bond capacity than to dielectric constant of the considered solvents,clarifying the hydrogen bond capacity could be more important than dielectric constant in determining the kinetics of monoethanolamine with CO_2.  相似文献   
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