凹凸棒石粘土吸附剂处理含镍(Ⅱ)废水的研究

采用凹凸棒石粘土吸附剂对含Ni(Ⅱ)废水的处理进行研究。用粘土和活化土吸附剂处理含Ni(Ⅱ)水样,探讨了不同实验条件如吸附剂用量、灼烧时间、处理时间等对Ni(Ⅱ)吸附率的影响,得出了最佳实验条件。实验结果表明：用该吸附剂在最佳条件下处理含镍量为71mg／L的废水,可使Ni(Ⅱ)的残余浓度远远降低。     

腐植酸文摘

用粒状腐植酸类炭质净化剂处理含镍电镀废水的研究(Ⅰ)陈丕亚杭月珍电镀工业排出的含Ni2+废水平均含Ni2+浓度为50～100mg/L。如不经净化直接排放,不仅浪费大量贵重金属,且影响人体健康,长期接触有致癌作用。净化含Ni2+电镀废水多采用化学沉降法、离子交换法等。近年来国外开始研究用腐植酸类炭质净化剂处理含Ni2+废水,吸附性能好,并讨论了影响大同风化煤净化含镍电镀废水的主要因素。摘自:《环境科学与技术》,1980(4)用粒状腐植酸类炭质净化剂处理含镍电镀废水的研究(Ⅱ)着重讨论大同风化煤吸镍机制,这对于了解大同风化煤吸镍特征,对原料…     

小波包分析-Elman神经网络同时测定废水中的铁、镍、铜

以非离子表面活性剂OP为增溶、增敏剂,以5-Br-PADAP为显色剂,建立了同时测定废水中铁、镍、铜的小波包分析一简单递归神经网络(Elman神经网络)分光光度法.该方法采用小波包分析处理吸收光谱数据,以滤除信号中的噪声,然后用Elman神经网络进行数据解析.将此方法应用于模拟废水以及印染厂废水中Fe(Ⅲ)、Ni(Ⅱ)、Cu(Ⅱ)的测定,回收率分别可达97.5%～102.5%,结果令人满意.     

离子交换剂在治理电镀含镍废水中的应用

本文综述了近年来采用离子交换树脂处理含镍废水方面的新发展,介绍了三种新方法:1)用阴离子交换树脂处理含镍废水;2)用螯合树脂处理含镍废水;3)用L型重金属处理剂处理含镍废水。列举了五个具体应用实例。1)离子交换——反渗透法。可使含镍量提高到260～280g/L,可回用于镀槽。2)浮床交换——移床再生工艺。处理后含Ni~(2+)浓度小于0.43 mg/L,达到排放标准,处理1m~3废水可盈利0.29元;3)螯合树脂法处理电镀镍铁合金废水。再生液中硫酸镍含量可达200g/L,可以用于镀槽。4)三阴柱处理镍、铜、锌氰络合物废水。第一柱吸附铜,第二柱吸附锌,第三柱吸附镍;5)L型重金属处理剂治理含Ni~(2+)废水。经二年的实践表明,处理后排出水中Ni~(2+)<0.5mg╱L,洗脱液中Ni~(2+)浓度可达15g/L左右。     

浅析电镀废水除镍

镍是第一类污染物,对人和环境危害很大。含镍电镀废水处理方法很多,有中和沉淀法、硫化物沉淀法、铁氧体沉淀法、膜分离法、吸附法等。试验表明,使用单一方法处理大型电镀工业园区含镍电镀废水难以达到相关标准。将电镀废水分类,综合使用各种方法,物化法和生化法联合,可以将电镀废水中镍降到0.1 mg/L以下。     

高分子重金属絮凝剂在水处理中应用的研究

以含镍废水为处理对象,主要探讨了高分子重金属絮凝剂(MHMF)对废水中镍离子和浊度的去除效果。与无机絮凝剂Al2(SO4)3、PAC相比较,MHMF处理含镍废水具有投加药量少,最佳适用pH值低,形成絮体快而且个体较大,絮体沉降性能好、不易破碎等特点。在pH=5.5～6时镍的去除率达98％,浊度的去除率也在98％以上。尤其是在处理具有浊度的含镍废水过程中,镍离子和致浊物质可相互促进各自的去除。     

吐温80-PAN分光光度法测定钢样中的镍

研究了以1-(2-吡啶偶氮)-2-萘酚(PAN)-吐温-80为显色体系,采用分光光度法测定钢样中的镍(Ⅱ)。在氨-氯化铵缓冲溶液体系中,镍(Ⅱ)与PAN形成红色稳定的络合物。其最大吸收波长为568 nm,表面摩尔吸光系数为ε568=4.62×104 L·mol-1·cm-1。镍(Ⅱ)含量在0~15μg/(25 m L)范围内服从比尔定律。采用联合掩蔽剂消除样品中的铁(Ⅲ)、铜(Ⅱ)、钒(Ⅴ)、铅(Ⅱ)、等对镍(Ⅱ)离子的干扰。使用该方法测定了38#、45#钢样中的镍(Ⅱ)含量,其RSD分别为2.60%、0.10%,加标平均回收率分别为101.48%、104.96%。此方法具有良好的准确性、选择性,且操作简便、快捷,结果满意。     

壳聚糖分离富集分光光度法测定微量镍

研究了壳聚糖对Ni(Ⅱ)的富集、洗脱性能及苯并噻唑重氮氨基偶氮苯BTDAB与Ni(Ⅱ)的显色反应,建立了微量镍的分离富集光度测定新方法。实验表明,壳聚糖对Ni(Ⅱ)吸附性能良好,其吸附的最佳pH为8.0,吸附在4h内已基本达到平衡;在非离子表面活性剂Triton X-100的存在下,BTDAB与Ni(Ⅱ)形成3:1的橙红色配合物,最大吸收波长位于550nm处,表观摩尔吸光系数为1.64×105L·mol-1·cm-1,镍含量在0-10μg/25mL范围内符合比尔定律。方法直接应用于废水中微量镍的测定,结果令人满意。     

含镍电镀废水处理技术研究概述

随着电镀工业的不断发展,电镀废水已逐渐成为当今世界最为严重的污染之一。镀镍技术则是一种应用相当广泛的电镀技术,也是含镍废水量不断增加的直接原因,含镍废水是一类污染物,对其管理及监控尤严格。文章介绍了镀镍工艺以及含镍废水的特点及危害,综述了镀镍工业含镍废水治理技术,介绍了化学沉淀法、离子交换法、膜分离技术、生物处理法等方法,并对各方法进行了分析总结。对含镍电镀废水进行深度处理,如何实现含镍电镀废水零排放,实现镍的回收和废水循环再利用等方面的资源化处理技术是当前发展的趋势。     

火焰原子吸收法中氘灯对测定高盐废水中镍的影响

三元前驱体行业产生的含镍废水含盐量较高,对镍的分析检测灵敏性和准确性影响较大。在本论文中采用火焰原子吸收法在开氘灯的情况下测定高盐废水中的镍,该方法能有效地测定镍含量,相对误差在7.2%以内,回收率在103.4%～106.8%范围,能够满足分析检测的灵敏性和准确性。     

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.