Fenton氧化法预处理高浓度制药废水的实验研究

采用Fenton法对高浓度制药废水进行预处理实验。主要考察了Fenton试剂氧化法预处理高浓度制药废水的影响因素,主要讨论pH值、FeSO4·7H2O投加量、反应时间对Fenton氧化工艺对制药废水中CODCr处理效果的影响。实验结果显示,pH值为4、反应时间100 min、FeSO4·7H2O投加量为0.024 mol/L、H2O2/Fe2＋投加比为11∶1,CODCr处理去除率为52.1%,可生化性BOD/COD为0.57,效果最为理想。     

Fenton试剂预处理农药废水实验

对Fenton氧化法预处理农药废水进行了研究,通过考察H2O2投加量、[Fe2 ]/[H2O2](摩尔比)、pH值、反应时间、Fenton试剂投加方式等因素对该农药废水化学需氧量(CODcr)、色度去除率的影响,确定了反应的最佳条件:即H2O2的投加量为50 mmol/L,[Fe2 ]/[H2O2]为1:10,pH值为3,反应时间为2h,Fenton试剂分4次投加.在此条件下CODcr去除率可达68.07%、色度去除率可达90.11%;Fenton氧化预处理后废水的可生化性也得到了大大提高.     

超声波强化Fenton试剂深度处理山梨酸废水的研究

采用超声强化Fenton(Fe2++H2O2)试剂,耦合氧化深度处理山梨酸废水。考察了超声功率、反应时间、反应温度、pH值、试剂投加量对CODCr去除率的影响。结果表明:在超声频率40kHz,超声功率400W,反应时间40min、反应温度60℃、pH值3.0、H2O2浓度0.22mol/L、Fe2+浓度0.04mol/L时,CODCr去除率达到95%以上。与单独使用Fenton试剂法相比,该方法反应时间短、反应温度低、试剂投加量小、CODCr去除率高。     

混凝沉淀-Fenton氧化法在垃圾渗滤液生化处理出水中的研究

采用混凝沉淀-Fenton氧化处理垃圾渗滤液生化处理出水,通过单因素试验研究了混凝沉淀和Fenton氧化中各因素对去除CODCr的影响,试验结果表明,最佳混凝试验工艺条件为:复合混凝剂比例n(无机组分)∶n(有机组分)为4.0∶1、p H值为8.5、混凝剂投加量0.6 g/L,CODCr的去除率可达到88.6%。Fenton氧化阶段,当体系p H值为4.0、H2O2投加量为16 mg/L、Fe SO4·7H2O投加量为6 g/L、反应时间为110 min时,CODCr去除率高达95.9%。     

UV-Fenton法处理草浆造纸废水的研究

采用UV-Fenton法对自偶氧化清洁制浆造纸废水进行处理.考察了废水pH、H2O2投加量、Fe2 投加量、反应时间以及紫外光强等对废水中CODCr去除率的影响,得到了最佳的工艺条件为pH 3.53、H2O2投加浓度46.19mmol/L、Fe2 投加浓度3.06 mmol/L,反应60 min后CODCr去除率达到67.13%,出水CODCr降到428 mg/L,改善了废水的可生化性,有利于进一步进行生化处理.     

响应面法分析Fenton氧化垃圾渗滤液的过程

利用统计学的方法对Fenton氧化垃圾渗滤液的影响因素进行了探讨和分析,考察了FeSO4?7H2O投加量,H2O2/FeSO4.7H2O比值和pH值对氧化垃圾渗滤液的影响。在FeSO4.7H2O投加量为0.01～0.02 mol/L、H2O2/FeSO4.7H2O比值1～5和pH值2～6的条件下,分析CODCr的变化。通过使用Design-Expert 5软件可得到1个二次响应曲面模型,最佳的FeSO4.7H2O投加量为0.013mol/L、H2O2/FeSO4.7H2O比值4.60和pH值4.45,从而CODCr的去除率也达到最大(69.85%)。     

Fenton/化学沉淀法处理垃圾渗滤液的研究

在分析和总结已有垃圾渗滤液处理技术的基础上,采用Fenton氧化和化学沉淀组合工艺开展了垃圾渗滤液的处理研究,并对工艺参数进行了优化。首先应用Fenton试剂对渗滤液进行氧化处理。实验表明,在p H为3、氧化时间为150min、Fe SO4·7H2O投加量为0.03 mol·L-1、H2O2/Fe2+投加比例为6∶1时,CODCr的去除率高达90.01%。再对经Fenton试剂处理过的垃圾渗滤液使用Mg Cl2·6H2O和H3PO4,在碱性条件下与渗滤液中的NH3-N发生化学反应,生成六水磷酸铵镁(Mg NH4PO4·6H2O)沉淀物。实验结果表明,在p H为9.5,试剂摩尔投加比n(NH4+)∶n(Mg2+)∶n(PO43-)=1∶1.3∶1.3的条件下,渗滤液中NH 3-N的去除率达到75.7%,CODCr最终去除率为93.1%。     

Fenton试剂预处理亚麻生产废水

采用Fenton试剂预处理亚麻生产废水。探讨了pH值、反应时间、H2O2投加量、FeSO4.7H2O投加量对去除CODCr的影响。试验结果表明:在pH值为4.5,反应时间为60 min,H2O2投加量为5 mL/L,FeSO4.7H2O投加量为1 500 mg/L,H2O2的投加为分批次的连续投加方式时,CODCr去除率为45%,m(BOD5)/m(CODCr)由0.21提高到0.53,出水中检测不到SS的存在,为后续生化处理创造了有利条件。     

氧化-絮凝-A/O处理甲基多巴生产废水研究

甲基多巴是一种降压药物,其生产废水具有高色度、高有机物浓度和生物难降解的特性.采用Fenton氧化-PAM絮凝-A/O生化工艺处理该废水.Fenton氧化处理的优化条件为:pH 5.0,n(Fe2 )∶n(H2O2)=1∶4,H2O2和绿矾投加质量浓度分别为5.0 g/L和10.2 g/U,反应时间2.0 h.PAM絮凝处理的优化条件为:pH 7.0,投加量16.7mg/L.经过Fenton氧化-PAM絮凝处理,CODCr去除率达到74%,脱色率达95%,B/C由0.17升到0.38,废水的可生化性明显提高.后续采用A/O工艺进一步处理,可再去除70%～80%的CODCr.     

Fendon试剂预处理草甘膦废水的研究

研究了用Fendon试剂预处理含难降解有机物的草甘膦废水,考察了反应pH值、H2O2/Fe2+投加比例、Fendon试剂投加量和反应温度对总磷去除率、COD去除率的影响.结果表明,在pH=3～4、H2O2/Fe2+投加摩尔比为4∶1、H2O2投加量为8 g·L-1,反应温度为90 ℃,反应时间为2 h的条件下,总磷去除率为95.7%、CODCr去除率为62.9%.由此可见,Fendon试剂能显著降低草甘膦废水中的总磷、CODCr值.     

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.     

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.     

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.     

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.