Ultrapyrolysis of automobile shredder residue

A fast pyrolysis (Ultrapyrolysis) process was employed to convert automobile shredder residue (ASR) into chemical products. Experiments were conducted at atmospheric pressure and temperatures between 700 and 850°C with residence times between 0.3 and 1.4 seconds. Pyrolysis products included 59 to 68 mass% solid residue, 13 to 23 mass% pyrolysis gas (dry) and 4 to 12 mass% pyrolytic water from a feed containing 39 mass% organic matter and 2 mass% moisture. No measurable amounts of liquid pyrolysis oil were produced. The five most abundant pyrolysis gases, in vol%, were CO (18–29), CO₂ (20–23), CH₄ (17–22), C₂H₄ (20–22) and C₃H₆ (1–11), accounting for more than 90% of the total volume. The use of a higher organic content ASR feed (58 mass%) resulted in less solid residue and more pyrolysis gas. However, no significant changes were noted in the composition of the pyrolysis gas.     

压电陶瓷变压器材料PMMN-PZT的研究

研究了一种四元系压电陶瓷变压器材料PMMN -PZT。XRD分析证明 ,采用二步法预合成的PMMN -PZT粉料不如一步法 ;SEM分析进一步证实了一步法预合成的粉料能制成性能更好的陶瓷样品。造粒工艺对陶瓷样品的显微结构和压电性能也有重要的影响。最后制得了性能较好的PMMN -PZT压电陶瓷材料 ,其Kp=0 .5 18,Qm=3887,tanδ =0 .71% ,εT3 3 /ε0 =70 1,d3 3 =2 0 3,基本上能满足压电变压器的要求     

过度开采对地下水水化学特征的影响研究

为探究过度开采对地下水水化学特征的影响,通过对比分析研究区1997年和2010年的地下水水位与水质资料,研究了过度开采条件下地下水水位与水化学特征的动态规律及两者之间的联系。研究结果表明:1997年和2010年研究区地下水水位与水化学特征的空间变化规律具有很高的一致性,表现为地下水水位降幅较大的区域对应的镁离子、硫酸盐含量增幅也相对较大,地下水水化学特征受地下水水位变化的影响较大。空间叠加分析结果表明:镁离子、硫酸盐与地下水水位变化较大的区域空间重合率分别为72.2%,53.1%。过度开采通过改变地下水补径排条件及饱和带、非饱和带的水环境变化对地下水水化学特征产生影响,因此对于地下水不可盲目、过度开采。     

Effects of the solvent polarity on the atom transfer radical polymerization of methyl methacrylate initiated by 4‐(chloromethyl)phenyltrimethoxysilane

The controllability of the atom transfer radical polymerization of methyl methacrylate in the polar solvent N,N‐dimethylformamide and the nonpolar solvent xylene with 4‐(chloromethyl)phenyltrimethoxysilane as an initiator and with CuCl/2,2′‐bipyridine and CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine as catalyst systems was studied. Gel permeation chromatography analysis established that in the nonpolar solvent xylene, much better control of the molecular weight and polydispersity of poly(methyl methacrylate) was achieved with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system than with the CuCl/2,2′‐bipyridine as catalyst system. In the polar solvent N,N‐dimethylformamide, unlike in xylene, the polymerization was more controllable with the CuCl/2,2′‐bipyridine catalyst system than with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2751–2754, 2007     

2003年上半年原油价格走势分析及预测

2003年上半年委内瑞拉供应量剧减，以及美伊战争等因素影响，上半年布伦特油价为28．17美元/桶，同比上涨19．7％，其中一季度为30．62美元/桶，二季度为25．80美元/桶。三、四季度世界石油需求增长有所回升，但欧佩克履约情况、伊拉克产量恢复情况及美国石油库存等是影响未来石油市场的不确定因素。预计三季度油价仍将起伏不定，布伦特油平均价格可能维持在28美元／桶左右，四季度为25．5美元/桶。     

高碳烯酸的氧化裂解

高碳烯酸的氧化裂解有多种方法。例如；高锰酸钾氧化、使用钴盐作催化剂的液相催化氧化、臭氧氧化、钌盐氧化、微生物氧化。对不同的氧化方法进行分析，使用乳化技术的钌盐氧化是最经济的氧化方法。     

多次顶空固相微萃取方法的原理及应用

详细讨论了多次顶空固相微萃取(MHS-SPME)技术的原理和影响因素,并与常用的固相微萃取(SPME)定量校正方法相比较,分析了该方法的优势和缺点。综述了多次顶空固相微萃取在食品、农业领域的应用情况,并对该方法存在的问题和发展前景进行了论述。     

山梨醇类聚丙烯成核剂的开发与应用研究进展

综述了山梨醇类聚丙烯成核剂产品在国内外的开发进展，介绍了该类成核剂在聚丙烯中的应用和效果，及其作用机理。     

Charge reduction and regeneration in K+, Na+, Mg2+, Ni2+ and Co2+-exchanged Wyoming Bentonite

Controlled calcination of ion-exchanged Wyoming Bentonite in the presence and absence of ammonia leads to layer charge reductions. Detailed chemical analyses of both unexchangeable and exchangeable species lead to the conclusion that in no case is there migration of the original interlamellar cations into the octahedral region of the layers although, in terms of ionic radius alone, Mg²⁺, Ni²⁺ and, possibly Co²⁺, might be expected to do so. The production of unexchangeable Mg, Ni or Co, is identified as resulting from high temperature hydrolysis leading to hydroxide or oxide formation.