EVA悬浮填料的制备及硝化反应的研究

用活性炭填充弹性高发泡乙烯／醋酸乙烯共聚物颗粒制备新型悬浮填料，在悬浮填料移动床工艺中为微生物提供附着生长的载体。载体具有通孔结构，从表面到内部形成不同溶解氧梯度，在反应器内发生同时硝化反硝化反应（SND）。研究表明，当双螺杆挤出温度为185℃、交联剂过氧化二异丙苯为1％（质量分数，下同）、发泡剂偶氮二甲酰氨为1．5％、活性炭为18％时，填料密度和空隙率分别达到0．85g／mL和60％。在复合式生物反应器中处理模拟生活污水，发生SND的工艺条件为：溶解氧（DO）为2．0～2．2mg／L，碳氮比（COD／YH4^＋-N，简写为C／N）为30，水力停留时间为5h。     

分子印迹菌丝体吸附树脂在印刷电路板废水处理中的应用

采用新型分子印迹菌丝体(Penicillium chrysogenum)吸附树脂处理印刷电路板废水,当铜的初始质量浓度为120 mg/L,pH=5时,静态吸附容量为53 mg/g左右,比商业树脂732提高15%左右;解析率在1 min即达到85%以上,而商业树脂732仅为11%.在中试实验中,连续运行80 h后,出口废水中铜质量浓度仍低于1.0 mg/L左右.与传统处理方法相比较,该法简化了废水处理工艺,节省大量的化学药品,大大降低了废水处理成本.     

湍流化学反应的分形数值模拟

基于涡串唯象概念和分形理论,建立了能够表达湍流多尺度结构物理特性的分形湍流化学反应模型,针对Steckler室内燃烧过程进行了数值模拟研究.湍流流动采用浮力修正的κ-ε双方程模型来模拟,辐射由Rosseland模型描述,整个模拟过程由ANSYS-CFX10.0实现.将模拟结果与Steckler的燃烧实验数据进行对比,并与EDC燃烧模型及文献中EBU燃烧模型的模拟结果进行对比.结果表明,FM燃烧模型模拟得出的温度、速度场分布与实验数据能够较好地吻合,是一种有前途的湍流化学反应模拟方法.     

反溶剂重结晶法制备萘普生超细微粒

在溶剂(丙酮)-反溶剂(水)体系下,采用反溶剂重结晶法制备了超细萘普生微粒。研究了不同溶剂-反溶剂体积比、重结晶温度、表面活性剂用量及陈化条件对重结晶产物粒径和形貌的影响。采用扫描电子显微镜(SEM)、表面吸附(BET)、红外光谱(IR)、X射线衍射(XRD)等检测手段对原料药和重结晶产物进行了对比分析。实验结果表明,当溶剂与反溶剂体积比为1:20,重结晶温度为4～8℃,表面活性剂聚乙烯吡咯烷酮(PVP)的质量分数为0.5%～1.0%,60℃下陈化2 h时。可得到短径300～500 nm,长径1～2μm的超细萘普生粉体。重结晶所得产物的晶型和物理性质均未发生变化,但粒度显著减小,形貌趋于规整且比表面积增加至原料药的5.3倍。     

Novel tin‐coupled star‐shaped medium vinyl butadiene rubber. I. Arm number and its effect on properties

To achieve low rolling resistance, high wet grip, and favorable overall performance, star‐shaped medium vinyl butadiene rubber (S‐MVBR) was designed and prepared by “core‐first” method, where novel multifunctional organolithium containing Sn atom as initiator, THF as structure regulator, and carbon–hydrogen compound as solvent. The results showed that coupling reaction between SnCl₄ and dilithium is stoichiometrical, and this method has much higher efficiency than the “arm‐first” method. When dilithium is composed of 4–10 repeating units, the average arm number of S‐MVBR is conveniently controlled between 3 and 5 by initiator functionality, which can be easily regulated by the mole ratio of active lithium of dilithium short chain to Cl^? in SnCl₄. As Sn coupling decreases numbers of noncrosslinking free ends, S‐MVBR has lower rolling resistance, dynamic heating and higher wet grip than linear MVBR. Meanwhile, mechanical properties and processing properties are improved. And the formation of multiarm structure has little effect on viscosity. S‐MVBR with arm number of 3.8 has optimal overall performance. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3917–3923, 2007     

POE-g-GMA对聚丙烯／聚磷酸铵复合材料玻璃化转变活化能的影响

以熔融反应挤出得到的POE-g-GMA作为增容剂，制备了增韧PP／APP复合材料。采用动态力学的方法，计算得到不同POE-g-GMA含量的PP／APP复合材料的玻璃化转变活化能。结果表明，在相同的测试频率下，接枝物POE-g-GMA的加入会导致PP／APP复合材料的内耗峰的峰温降低，而内耗峰的强度增加；降低复合材料的玻璃化转变活化能。这说明在PP／APP复合体系中加入POE-g-GMA可以改善PP和无机填料APP之间的相容性，使复合材料中的PP分子链段在进行玻璃化转变时更加容易。只需要较低的活化能就可以了。从中可以判断出接枝物POE-g-GMA对于PP／APP共混体系来说是很好的相容剂。     

环氧有机硅油改性丙烯酸树脂的合成及性能

以偶氮二异丁腈为引发剂,通过丙烯酰氧基硅油与丙烯酸酯类单体的自由基共聚合反应,同时环氧828与丙烯酸共聚侧链羧基进行开环反应,合成以乙醇为主要溶剂的单相均匀牛顿型环氧有机硅油改性丙烯酸树脂。并对树脂涂膜的稳定性及硬度、耐水煮性,附着力等性能进行了研究。得到的树脂具有良好的热储稳定性,颜料广泛润湿性。环氧有机硅油改性丙烯酸树脂涂膜具有光泽高、硬度好、丰满度高、玻璃附着力强、耐水煮性好与透明性高等优异性能,适用于高档玻璃烤漆。     

纳米CaCO3对聚烯烃色母粒色彩性能的影响

用纳米CaCO3和普通活化CaCO3分别替代不同比例的颜料应用于聚烯烃色母粒中，利用测色仪测定色母粒制成的薄膜和样板制品的着色力和遮盖力，研究其对色母粒色彩性能的影响，并进行比较。结果表明，在不改变被着色制品色彩性能的前提下，纳米CaCO3可以替代部分颜料，且效果略优于普通活化CaCO3。色母粒中纳米CaCO3含量为10％（质量分数，下同）时，薄膜制品的光密度最大，遮盖力最高，分散效果最好。颜料的着色力在纳米CaCO3含量为20％时提高程度最大，而且体系的分散性也得到改善。     

多语种网络文本快速新词抽取

从网络文本中提取新词是网络信息处理中的一个重要问题,在信息检索、文本挖掘、词典编纂、中文分词等领域中都有重要应用。本文提出了一种与语言无关的快速新词提取算法,首先针对后缀树的数据结构将多语言文本进行统一编码,然后使用改进的统计方法在双后缀树上以线性时间统计重复串与邻接类别,并计算字符串的整体度,同时通过剪枝大幅度减少计算量,在中、英文语料上较好地实现了新词的抽取及排序。     

Effects of the reinforcement and toughening of acrylate resin/CaCO3 nanoparticles on rigid poly(vinyl chloride)

Novel composite particles based on nanoscale calcium carbonate (nano‐CaCO₃) as the core and polyacrylates as the shell were first synthesized by in situ encapsulating emulsion polymerization in the presence of the fresh slush pulp of calcium carbonate (CaCO₃) nanoparticles. Subsequently, these modified nanoparticles were compounded with rigid poly(vinyl chloride) (RPVC) to prepare RPVC/CaCO₃ nanocomposites. At the same time, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were investigated, and the synergistic effect of modified nanoparticles with chlorinated polyethylene (CPE) was also studied. The results showed that in the presence of nano‐CaCO₃ particles, the in situ emulsion polymerization of acrylates was carried out smoothly, and polyacrylates successfully encapsulated on the surface of nano‐CaCO₃ to prepare the modified nanoparticles, breaking down nano‐CaCO₃ particle agglomerates, improving their dispersion in the matrix, and also increasing the particle–matrix interfacial adhesion. Thus, the effects of the reinforcement and toughening of these modified nanoparticles on RPVC were very significant, and the cooperative effect of the nanoparticles with CPE occurred in the united modification system. Scanning electron microscopy analyses indicated that large‐fiber drawing and network morphologies coexisted in the system of joint modification of nanoparticles with CPE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3940–3949, 2007