混凝-Fenton法去除含油废水COD_(Cr)的试验研究

采用混凝-Fenton法处理盘锦油田含油废水,分析PAC用量、PAM用量、pH值、H_2O_2的投加量、FeSO_4·7H2O的投加量、反应温度和反应时间等各因素对COD_(Cr)去除效果的影响,并确定最佳的处理条件。结果表明,混凝试验中PAC的投加量为200 mg/L和PAM的投加量为0.6 mg/L时效果最好;Fenton反应的最佳条件为:pH值为4,H_2O_2投加量为37.8 mmol/L,FeSO_4·7H_2O投加量为3.78 mmol/L,反应温度为75℃,时间为30 min,此时Fenton反应进行最彻底,含油废水COD_(Cr)去除率最高。     

微波辅助Fenton试剂氧化法深度处理印染废水的研究

以实际印染废水排放口的出水为研究对象,考察了微波辅助Fenton试剂氧化法深度处理印染废水的效果和影响因素。结果表明,微波辅助Fenton试剂氧化法对印染废水具有良好的深度处理效果,在进水COD_(Cr)为150~160 mg/L的条件下,处理出水COD_(Cr)小于60 mg/L,达到《污水综合排放标准》(GB 8978-1996)的一级标准。在试验条件下,最佳的反应参数为:初始pH为2.5,FeSO_4·7H_2O投加量为4.4 g/L,30%H_2O_2投加量为8 g/L,微波功率为500 W,微波反应时间为5 min。微波辅助Fenton试剂氧化法的COD_(Cr)去除率可达65.1%。     

Fenton法处理DDNP废水的实验研究

采用Fenton法处理DDNP废水,考察H_2O_2与FeSO_4的体积比、试剂总投加量、pH、反应时间等因素对去除效果的影响.实验结果表明,pH为6,质量分数为30%的H_2O_2投加量为40 mL/L左右、Fe~(2+)投加质量浓度为4.56 g/L,振荡1.5 h,COD_(Cr)去除率可达94.78%,色度去除率可达94.38%.     

钕铁硼回收过程的废水预处理研究

本文采用Fenton试剂对钕铁硼废料回收废水处理进行试验研究,试验研究了不同初始pH、不同反应时间、不同FeSO_4·7H_2O投加量以及不同H_2O_2/投加量对CODcr去除率的影响,试验研究表明在pH为3-5、反应时间为2h、FeSO_4·7H_2O投加量0.006mol/L,H_2O_2投加量为2mL/L时,废水CODcr去除率可以达到70%以上。由于废水的酸度和Fe2+浓度非常大,采用将废水进行加碱混凝沉淀的方法可以去除废水中大部分可沉淀的阳离子和胶体态的有机物,减轻后续Fenton氧化的压力。     

Fenton氧化法处理机械加工清洗废水的实验研究

研究了Fenton试剂处理机械加工清洗废水的影响因素及其适宜操作条件。实验结果确定的适宜操作条件为:在原水COD_(Cr)约2 000 mg/L时,n_(H_2O_2)/n_(Fe~(2+))=37.6,H_2O_2的投加量40 mL/L,pH=4,反应时间2.5 h,此时COD_(Cr)的去除率可达91.4%。同时考察了聚丙烯酰胺与Fenton试剂的协同效果。适宜操作条件下COD_(Cr)的去除率可达93.2%。     

改性粉煤灰吸附-Fenton氧化深度处理制药废水的研究

针对制药废水二级生化处理出水仍存在COD_(Cr)和色度偏高的不足,试验采用改性粉煤灰吸附-Fenton氧化法对其进行深度处理研究。探讨了pH值、H_2O_2投加量、Fe~(2+)投加量、反应时间等因素对COD_(Cr)去除率的影响。结果表明,在加热温度为400℃时粉煤灰改性效果最佳。在此最佳改性粉煤灰吸附条件下,当系统pH值为5、反应时间为2 h,H_2O_2(30%)投加量为300 mg/L、Fe~(2+)投加量为100 mg/L的条件下,制药废水二级生化出水中的COD_(Cr)去除率达到74.5%。     

垃圾填埋场渗滤液预处理的Fenton氧化工艺试验

采用Fenton氧化对垃圾渗滤液进行预处理研究。结果表明:COD_(Cr)的去除率随H_2O_2投加量的提高,先升高后下降;随FeSO_4投加量的提高,先升高后趋于平缓;随反应时间的延长,趋于平缓;随pH值的升高,先升高后下降。TN的去除率与投药的比例和反应条件关系不大,主要是氨氮的去除,始终保持在17%～30%。在COD_(Cr)质量浓度为2 500～3 000 mg/L、总氮质量浓度为950～1 400 mg/L时,最佳H_2O_2投加量为6 mL/L,FeSO_4投加量为2.5 g/L,最佳反应时间为30 min,反应pH值为4,COD_(Cr)去除率可达69.53%,总氮去除率可达22%,色度去除率可达98.33%,B/C由0.15提高至0.23。Fenton氧化作为垃圾渗滤液的预处理具有较高可行性的。     

利用Fenton试剂对松香加工废水预处理的试验研究

研究了采用Fenton法对难以生物降解处理的松香加工废水进行预处理的方法及影响因素。结果表明,最佳运行条件为初始pH=3,n(H_2O_2)/n(Fe~(2+))=3︰1,m(H_2O_2)/m(COD_(cr))=10︰1,反应时间30 min。经Fenton法处理后,当pH=3,V(H_2O_2)=0.90 mL,m(FeSO_4·7H_2O)=0.8181 g,出水CODcr为20.5 mg/L,COD_(cr)去除率达到94.86%,Fenton法是深度处理松香加工废水的一种有效工艺,同时表明Fenton试剂对松香加工废水中的有机物有明显的降解作。     

UV/TiO_2光催化氧化处理鲁奇废水生化出水的试验研究

采用UV/TiO_2反应体系对鲁奇废水生化出水进行了光催化氧化试验,考察了pH、TiO_2投加量、反应时间和外加H_2O_2对COD_(Cr)去除率的影响。结果表明:中性及酸性条件下更有利于UV/TiO_2光催化降解鲁奇废水生化出水中的COD_(Cr);在pH值=7和1.0 g/L TiO_2投加量条件下,反应4 h后,COD_(Cr)去除率为61.17%。UV/TiO_2反应体系外加一定量H_2O_2是否会提高其COD_(Cr)去除率与具体的反应体系有关。     

橡胶硫化促进剂DZ生产废水的预处理实验研究

采用Fenton氧化法对橡胶硫化促进剂生产废水进行预处理,考察了酸析法以及H_2O_2投加量、Fe⁽²⁺⁾投加量、pH值、反应时间对Fenton氧化法COD去除率的影响。结果表明,Fenton氧化法处理该废水的最佳反应条件为:pH值为3,H_2O_2投加量为55 mL/L,Fe(2+)投加量、pH值、反应时间对Fenton氧化法COD去除率的影响。结果表明,Fenton氧化法处理该废水的最佳反应条件为:pH值为3,H_2O_2投加量为55 mL/L,Fe⁽²⁺⁾投加量为2.8 g/L,反应时间为40 min。此时COD的去除率达82.91%。将酸析与Fenton氧化法联合后COD的去除率可达到85.78%,效果良好,为后续蒸发结晶分离氯化钠、硫酸钠奠定了基础。     

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.