水热法合成纳米Fe_3O_4及其对含酚废水的处理

通过水热法制备了纳米四氧化三铁,采用X射线衍射仪、透射电子显微镜对其进行了表征。以合成的纳米四氧化三铁为催化剂,过氧化氢为氧化剂,催化氧化含邻苯二酚的模拟废水和含邻甲苯酚的工业废水。结果表明:含邻苯二酚模拟废水和含邻甲苯酚的工业废水的挥发酚去除率分别为99.9%和99.3%,化学需氧量下降率分别为87.5%和95.4%。纳米四氧化三铁作为催化剂多次循环使用后仍具有较高的催化活性。通过亚甲基蓝捕捉法,检测了催化氧化反应中羟基自由基的产生并确定了H2O2的投料方式,探讨了邻苯二酚模拟的催化氧化降解途径。     

湿式催化氧化法处理含酚清洗废水的研究

针对化工集装罐清洗废水中含酚废水浓度大的特点,采用湿式催化氧化法进行了较深入的研究。对硝酸铜-AC制备CuO/AC催化剂过程中的浸渍液浓度、焙烧温度、焙烧时间等影响因素进行探讨;用该催化剂催化氧化降解模拟苯酚废水,对反应温度、氧化剂投加量、催化剂投加量、反应时间等工艺参数进行优化,确定最佳反应条件并进行了应用研究。研究结果表明,硝酸铜-AC制备CuO/AC催化剂的最佳条件为:硝酸铜质量分数为3%,浸渍温度为30℃,浸渍时间为6 h,焙烧温度为300℃,焙烧时间为3 h。湿式催化氧化法处理苯酚废水的最佳工艺条件为:反应温度为170℃,反应时间为1 h,催化剂投加质量浓度为2 g/L,氧化剂H2O2按m(H2O2)∶m(COD)=3投加,含酚清洗废水的COD去除率达到95%以上,处理效果显著。     

铁酸盐/微波催化氧化处理水中苯酚的工艺研究

采用共沉淀法制备了具有尖晶石结构的铁酸盐催化剂系列,并将其应用于微波诱导催化氧化处理含酚废水,筛选出苯酚降解效果最佳的Fe-Cu催化剂.XRD和IR的测试结果表明,Fe-Cu除了具有α-Fe2O3的特征峰和尖晶石结构的特征峰,还存在不同于其它铁酸盐的衍射峰和吸收峰.对于 300 mg/L的模拟含酚废水,最佳的处理工艺条件为:催化剂用量为含酚废水质量的1%,H2O2质量浓度 750 mg/L,微波输出功率 700 W,辐射时间 10 min,反应温度控制为70℃,溶液pH值4～6.在此条件下,苯酚降解率可达96.89%.催化剂连续使用10次后苯酚降解率仍达96.07%.     

铜铁复合层柱粘土的制备及其在含酚废水处理中的应用

以蒙脱石为原料，利用共聚法合成了铜铁复合层柱粘土催化剂。通过XRD、FTIR和N₂吸附-脱附等检测方法对其结构进行了表征。结果证实，交联剂成功插入到蒙脱石层间，所得催化材料具有较大的比表面积。将其作为催化剂，采用催化湿式过氧化物氧化处理含酚废水,实验结果表明，与铁、铁铝等层柱粘土相比，铜铁复合层柱粘土在苯酚处理浓度、催化剂用量、反应时间以及初始pH适用范围等方面都有较大的改善。在最佳工艺条件下，苯酚去除率可达99%，pH＝3~9都具有较高的去除效果，平均去除率达97%以上，循环使用四次后去除率仍大于90%。     

吸附-氧化组合工艺除酚实验研究

研究了在气液固三相流化床内使用Fenton试剂与H-103树脂组合联用处理模拟含酚废水的新工艺。探讨了pH值、反应时间、树脂固含率、H2O2和Fe2+的初始浓度等因素对苯酚去除率的影响。实验结果表明:在模拟含酚废水pH=4、苯酚质量浓度为1 000 mg/L、温度为25℃、通气量为0.12 m3/h的条件下,单纯采用吸附法处理,苯酚去除率为86.3%;单纯采用氧化法处理,苯酚去除率为95.5%;而采用氧化-吸附组合法,苯酚去除率能达到98.7%。组合法对苯酚的去除效果明显优于单一方法。     

磁性铁基氧化物纳米粉体的制备及其在含酚废水中的应用

分别采用水热法和共沉淀法制备了不同形貌的Fe3O4纳米粉体,以下简称催化剂1和催化剂2,并采用XRD、TEM等手段对其进行了结构和性能的表征。以合成的Fe3O4纳米粉体作为催化剂,采用湿式过氧化氢氧化法（CWPO）处理模拟含酚废水,探讨了不同的反应条件对水处理效果的影响。结果表明：在50℃,含酚废水浓度为1000 mg/L,20%H2O2用量35 mL/L,为1.5 g/L的条件下,用催化剂1湿式催化氧化苯酚,反应180 min,COD和挥发酚的去除率分别为72.99%和88.19%;在60℃,含酚废水浓度为1000 mg/L,20%H2O2用量45 mL/L,催化剂添加量为2.0 g/L的条件下,用催化剂2湿式催化氧化苯酚,反应180 min,COD和挥发酚的去除率分别为77.68%和94.71%。     

非均相类Fenton试剂处理焦化废水的研究

将Fe3+负载在3种载体上制备出3种催化剂,并研究了它们催化H2O2产生羟基,对苯酚模拟废水的吸附降解效果,发现将Fe3+负载在活性炭上对模拟废水处理效果好.用自制的载铁活性炭催化双氧水降解苯酚废水,进行了正交试验和单因素试验,探讨了催化剂用量、双氧水浓度、pH等因素对废水的CODCr去除率的影响.研究结果表明催化剂用量为1.5 g,H2O2质量分数为2%,pH为5时,载铁活性炭处理稀释后的焦化废水,CODCr去除率达到95%以上.     

含苯酚有机废水微波联合二氧化氯催化氧化处理技术

含苯酚有机废水的污染性和危害性较大，微波催化氧化技术是处理含苯酚有机废水的一种非常有效的方法。因此，室内以Mn-x作为催化剂，以ClO₂作为氧化剂，辅助以微波加热，对模拟含苯酚有机废水进行了室内氧化处理实验，并对其工艺参数进行了优化。结果表明，对含苯酚浓度为100mg·L^-1的有机废水，微波联合ClO₂催化氧化处理技术的最佳工艺条件为：催化剂Mn-x的加量为2000mg·L^-1、Cl O2的浓度为200mg·L^-1、苯酚废水pH值为7、微波功率为75W、处理反应时间为7min，此时含苯酚有机废水的苯酚去除率可达95%以上，达到了良好的处理效果。另外，与其他5种不同处理工艺对比结果显示，微波联合ClO₂催化氧化处理技术对含苯酚有机废水的处理效果最好，微波和催化剂的联合诱导作用能够显著提高ClO₂氧化处理苯酚的效率。     

不同催化剂对超临界水氧化降解含酚废水的研究

采用四种不同催化剂过氧化氢催化氧化高浓度含酚废水.该工艺条件下,温度升高,相应反应速率加快,在反应前1.5 min,苯酚去除率快速增加.该工艺条件下,硝酸铜是最佳催化剂,且在反应开始阶段(0～1.5 min),硝酸铜催化降解含酚废水,符合一级动力学模型.     

过氧化氢超临界水催化氧化含酚废水的研究

含酚废水是一种典型的工业废水,毒性大,可生化性差.炼焦、煤炭气化、炼油厂、塑料、农药、钢铁和酚醛树脂生产等许多化工作业都会形成大量含酚废水.本文研究了超临界水氧化法处理高浓度含酚废水.通过实验室小型实验,研究了H2 O2用量、反应时间、反应温度对苯酚去除率的影响.实验结果表明,在实验条件下,去除效果较好,苯酚的最佳去除...     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.