壳聚糖为基质的染料亲和吸附剂对重金属离子的吸附平衡及动力学研究

以反相悬浮交联法制备了壳聚糖微球载体,并偶联染料配体(CibacronBlueF3GA),制得了新型染料亲和吸附剂。研究了吸附剂与金属离子Cu2 、Pb2 、Cd2 之间的吸附行为。结果表明,在较高的初始金属离子浓度(200￣500mg·L-1)下,金属离子在吸附剂中的平衡吸附过程较好地符合Langmiur吸附等温式,吸附剂对Cu2 、Pb2 、Cd2 的最大吸附量分别为92.12、115.40、39.78mg·g-1;吸附动力学可用拟二级速率方程来描述,计算值与实测值吻合甚好;吸附剂对各重金属离子的吸附选择性依次为:Pb2 >Cu2 >Cd2 。     

氨基和羧基功能化磁性微球去除水溶液中Cd(Ⅱ)和Pb(Ⅱ)

以甲基丙烯酸和丙烯酰胺为功能单体,通过悬浮聚合法制备了氨基和羧基双功能化的磁性复合微球(Fe3 O4@SiO2-NH2/COOH),并探讨了其对水溶液中Cd(Ⅱ)和Pb(Ⅱ)的吸附性能.X-射线衍射(XRD)分析表明,制备的磁性吸附剂内核为Fe3 O4.红外光谱(FT-IR)和扫描电镜(SEM)测试表明,氨基和羧基对Fe3 O4@SiO2表面改性成功.吸附试验显示,Fe3O4@SiO2-NH2/COOH吸附Cd(Ⅱ)和Pb(Ⅱ)的最优pH值分别为5.0和5.5,吸附过程均符合动力学准二级模型和Langmuir吸附等温模型,吸附剂对Cd(Ⅱ)和Pb(Ⅱ)最大吸附量分别为207.807 mg/g和168.995 mg/g.实际饮用水样中Cd(Ⅱ)和Pb(Ⅱ)的吸附表明,去除率分别可达97.74％和91.44％.该磁性吸附剂对两种重金属离子吸附量大、去除率高,具有良好的实际应用潜力.     

MgFe2O4@PDA@PAMAM纳米复合材料对重金属离子的选择吸附性

以快速冷却处理获得的MgFe_2O_4纳米颗粒为磁核,经多巴胺自聚合(PDA)修饰和聚酰胺-胺(PAMAM)大分子接枝,制备高磁性MgFe_2O_4@PDA@PAMAM纳米复合材料,考察了MgFe_2O_4@PDA@PAMAM纳米复合材料对中性水溶液中Cu(Ⅱ)、Pb(Ⅱ)、Cd(Ⅱ)和Hg(Ⅱ) 4种重金属的吸附性能。结果表明:通过快速冷却的处理方式改变MgFe_2O_4晶粒内的金属离子分布,可获得具有高饱和磁化强度的MgFe_2O_4纳米材料;所制备的MgFe_2O_4@PDA@PAMAM纳米复合材料对4种重金属离子具有高的吸附能力,其中对Cu(Ⅱ)、Pb(Ⅱ)、Cd(Ⅱ)和Hg(Ⅱ)的饱和吸附容量分别为108.32、179.54、50.24和39.6 mg/g,选择吸附性顺序从高到低依次为Pb(Ⅱ)、Cu(Ⅱ)、Cd(Ⅱ)、Hg(Ⅱ)。     

改性海泡石对废水中Pb2^＋、Hg2^＋、Cd2^＋1吸附性能的研究

用盐酸溶液对海泡石进行处理和在450C灼烧，制备出改性海泡石。在动态条件下，研究了改性海泡石对重金属离子Pb2^ 、Hg2^ 、Cd2^ 的吸附效果及吸附条件。同时探讨了改性海泡石对重金属离子Pb2^ 、Hg2^ 、Cd2^ 的吸附机理。合Pb2^ 、Hg2^ 、Cd2^ 的冶金废水经改性海泡石吸附后，重金属离子含量显著低于国家排放标准。     

香草醛改性壳聚糖对水中Cu2＋，Pb2＋的吸附性能探讨

研究了香草醛与壳聚糖在pH值为6．8和5．5时,分别对水中Cu2＋,Pb2＋的吸附容量达到476．7mg／g和382．94mg／g。当吸附剂的用量小时,其吸附效果令人满意,可以作为自来水中祛除金属离子,净化水质的吸附剂。     

浮游球衣菌-纳米Fe_3O_4生物吸附剂处理电镀废水中Cd(Ⅱ)和Cr(Ⅵ)的研究

文章研究了浮游球衣菌-纳米Fe3O4生物吸附剂对重金属离子Cd(Ⅱ)和Cr(Ⅵ)的吸附性能,结果表明,此生物吸附剂对Cd(Ⅱ)和Cr(Ⅵ)有一定的吸附作用,当处理废水的pH为5.5、菌体投加量为0.3 g·L-1时,对20 mg·L-1含Cd(Ⅱ)和Cr(Ⅵ)废水的去除率分别为89%和68%。吸附-解吸试验结果显示,生物吸附剂可重复利用3次,在使用第3次时,Cd(Ⅱ)和Cr(Ⅵ)的去除率仍可达64%和42%。     

改性海泡石对废水中Pb2+、Hg2+、Cd2+ 吸附性能的研究

用盐酸溶液对海泡石进行处理和在450℃灼烧,制备出改性海泡石。在动态条件下,研究了改性海泡石对重金属离子Pb2+、Hg2+、Cd2+的吸附效果及吸附条件。同时探讨了改性海泡石对重金属离子Pb2+、Hg2+、Cd2+的吸附机理。含Pb2+、Hg2+、Cd2+的冶金废水经改性海泡石吸附后,重金属离子含量显著低于国家排放标准。     

聚丙烯酸钠包覆Fe_3O_4磁性交联聚合物的制备及其对Pb(Ⅱ)和Cd(Ⅱ)的吸附性能

采用溶液分散聚合和Ca2+表面交联制备了聚丙烯酸钠包覆Fe_3O_4的磁性交联聚合物(CPAANa@Fe_3O_4),对其进行了XRD、FT-IR、SEM和TGA等表征。以CPAANa@Fe_3O_4为吸附剂研究了CPAANa@Fe_3O_4对水溶液中Pb2+、Cd2+的静态吸附,考察了溶液p H、吸附剂投加量、金属离子初始浓度对吸附的影响。结果表明:CPAANa@Fe_3O_4在p H=2~6范围内均具有较好的吸附性能,当吸附剂投加量分别为1.0 g·L-1和1.6 g·L-1时对初始浓度分别为200 mg·L-1的Pb2+和100 mg·L-1的Cd2+的去除率达到最大,可使Pb2+实现达标排放(GB8978—1996);CPAANa@Fe_3O_4对Pb2+和Cd2+的吸附动力学符合准二级模型,吸附等温线符合Langmuir模型,对Pb2+和Cd2+的最大吸附量分别为454.55 mg·g-1和275.48 mg·g-1。将CPAANa@Fe_3O_4用于处理实际电解矿浆废水,发现能有效吸附其中的Pb2+和Cd2+,具有潜在实用价值。     

改性豆渣吸附重金属Pb(Ⅱ)的性能研究

以豆渣(BD)为原料,研究了用NaOH(NBD)、乙二胺(EBD)化学改性豆渣作为吸附剂,吸附废水中的重金属离子Pb(Ⅱ)。研究了溶液初始浓度、吸附温度、溶液pH、吸附时间对改性豆渣吸附废水中重金属离子Pb(Ⅱ)吸附性能的影响,由此得出了改性豆渣吸附剂的最佳吸附条件。并对改性豆渣吸附剂吸附Pb(Ⅱ)进行一级动力学与二级动力学拟合,拟合结果表明,该吸附过程更符合二级动力学模型。吸附过程为物理化学吸附行为。改性豆渣吸附剂吸附Pb(Ⅱ)等温线较符合Freundlich方程,吸附过程为多层吸附。热力学参数显示,改性豆渣吸附Pb(Ⅱ)的过程为吸热、自发的过程。实验结果表明,改性豆渣吸附剂对Pb(Ⅱ)的吸附效果明显优于未改性豆渣吸附剂。     

改性豆渣吸附重金属Pb(Ⅱ)的性能研究

以豆渣(BD)为原料,研究了用NaOH(NBD)、乙二胺(EBD)化学改性豆渣作为吸附剂,吸附废水中的重金属离子Pb(Ⅱ)。研究了溶液初始浓度、吸附温度、溶液pH、吸附时间对改性豆渣吸附废水中重金属离子Pb(Ⅱ)吸附性能的影响,由此得出了改性豆渣吸附剂的最佳吸附条件。并对改性豆渣吸附剂吸附Pb(Ⅱ)进行一级动力学与二级动力学拟合,拟合结果表明,该吸附过程更符合二级动力学模型。吸附过程为物理化学吸附行为。改性豆渣吸附剂吸附Pb(Ⅱ)等温线较符合Freundlich方程,吸附过程为多层吸附。热力学参数显示,改性豆渣吸附Pb(Ⅱ)的过程为吸热、自发的过程。实验结果表明,改性豆渣吸附剂对Pb(Ⅱ)的吸附效果明显优于未改性豆渣吸附剂。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、环氧树脂、不饱和聚酯树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。