EDTA络合-球磨法制备超细棒状BaSO4

采用EDTA络合-球磨法在室温下制备超细沉淀BaSO_4,研究了工艺参数对BaSO_4粒度分布和形貌的影响。通过XRD、SEM、激光粒度分布仪和FTIR等分析手段对产物的晶相、形貌和粒度进行表征,并探讨了反应机理。结果表明:BaCO_3浓度、EDTA的添加量和反应时间对BaSO_4的粒径影响较大,Na_2SO_4的添加速度对粒度影响相对较小。随着反应体系pH增大,BaSO_4颗粒形貌由不规整的针状逐渐转变为竖直排列的棒状团簇体,并且颗粒边缘趋于光滑。在BaCO_3浓度为0.2 mol·L~(-1),BaCO_3、EDTA、Na_2SO_4摩尔质量比为1:0.5:1.2,反应体系pH=8时可以得到平均粒径为130 nm均匀分散的棒状团簇体沉淀BaSO_4微粒。     

固体聚硅酸铁铝混凝剂的制备及其混凝除磷研究

以硅酸钠、硫酸铁、硫酸铝、硬脂酸钙为原料,制备了固体聚硅酸铁铝(PSAF)混凝剂,并以桂林市某污水处理厂二级生物处理后的出水为原水,研究了在最佳制备工艺条件下制备的固体PSAF混凝剂投加量和溶液pH对其混凝效果的影响。正交试验结果表明,制备固体PSAF混凝剂的优化工艺条件为:硅酸钠聚合的pH为2.5,溶液硅酸钠的浓度0.4 mol.L-1,Al3+与Fe3+的摩尔比5:5,加入铁铝混合液的温度为30℃,超声时间为40 min,硬脂酸钙的质量浓度为0.10g.L-1;混凝试验结果表明,当原水TP的质量浓度为1.23 mg.L-1、pH为7.5、固体PSAF的最佳投药量为125 mg.L-1时,TP的去除率为91.03%,COD去除率为70.3%,浊度去除率为60%。在pH为6.0～8.0时,固体PSAF除磷效果较好。     

改性树脂对高浓度硅酸的吸附去除

通过接枝法对普通的阴离子交换树脂进行改性,研究了改性树脂对高浓度硅酸溶液中已经形成的聚硅酸的吸附能力及吸附去除机理.结果 表明,改性树脂能够直接吸附高浓度硅酸溶液中已经形成的聚硅酸,其吸附量为13.48 mg·g-1,是对单硅酸吸附量的两倍.吸附过程中,聚硅酸粒径变化趋势和SEM观察结果表明,吸附机理主要以直接吸附粒径小于0.45 μm的聚硅酸为主,通过吸附小颗粒硅酸促进溶液中大颗粒分解为小颗粒,小颗粒继续吸附在树脂上,最后在树脂上形成了大片聚硅酸的吸附.     

味精中段废水处理的研究

采用石灰乳中和并沉淀味精废水中的硫酸盐.试验结果表明,CaO的最佳添加量约为20 g·L-1废水,SO42-的浓度可以从8000 mg·L-1降到450 mg·L-1,去除率可达90 %.     

蒙脱石／粉煤灰颗粒复合材料吸附含镍废水的研究

对蒙脱石/粉煤灰颗粒复合材料吸附镍离子的影响因素进行了考察.试验表明,蒙脱石/粉煤灰颗粒复合材料最佳吸附工艺条件为:颗粒吸附材料用量为0.2g·mg1,溶液pH为中性,振荡频率为95 r·min-1,振荡时间为50min,初始浓度为40 mg·L-1.在最佳条件下处理初始浓度为40 mg·L-1的含镍废水,吸附率为99.29%,处理后残余浓度为0.28 mg·L-1,达到国家一级排放标准(1.0 mg·L-1).     

NaOH处理镨黄表面对其粒径的影响研究

为了解不同浓度Na OH溶液处理镨黄表面对其粒径的影响。配制了不同浓度的Na OH溶液对镨黄进行处理并用无水乙醇淋洗过滤,运用分光光度计,激光粒度仪分别对其滤液和滤渣进行分析;对不同浓度Na OH溶液处理后镨黄进行纯水分散,对照未处理的镨黄,用显微镜和自然沉降实验进行分析。结果:过滤处理后滤液分层,但无水乙醇与Na OH溶液混合物为透明不分层;其中30%Na OH处理的滤液中小颗粒最多,10%Na OH处理的滤液中小颗粒最少;激光粒度仪测量干燥滤渣时,颗粒大小顺序为:原镨黄10%Na OH镨黄20%Na OH镨黄30%Na OH镨黄。200倍的显微镜下观察到纯水中的粒径大小为:原镨黄10%Na OH处理镨黄20%Na OH处理镨黄30%,水中的完全沉降时间和沉淀表面层白色深浅顺序为10%Na OH镨黄20%Na OH镨黄30%Na OH镨黄。结果表明:Na OH处理过的镨黄在无水乙醇中的相容性大于水中且阻碍乙醇和水的互溶;浓度高的Na OH溶液处理镨黄,过滤后滤液中小颗粒量越多,滤渣的小颗粒量越少,但滤渣干燥后颗粒的平均粒径越大,而在纯水中的颗粒越小,沉降时间越长,完全沉淀后沉淀表面白色越深。     

沉淀硅酸的制造法

本发明的沉淀硅酸是BET比表面积15～110m~2/g,松密度98—750g/l,松密度值相当于普通橡胶补强用沉淀硅酸的3倍的高松密度沉淀硅酸。其制备特点在于先由用热水稀释的硅酸钠溶液和浓硫酸(96％)为原料,以控制浓硫酸的添加速度制得沉淀硅酸,再加入浓硫     

火电厂处理EDTA酸洗过洗水的回用方法

探讨了火电厂利用反渗透循环处理EDTA过洗水的系统.EDTA过洗水通过反渗透处理,淡水出口的水质指标达到废水排放标准,COD<130mg·L-1,EDTA浓度未检出,出口铁离子质量浓度为600mg·L-1.浓水出口废水用碱法回收EDTA,回收率约为80%.     

导电浆料用超细铜粉的制备

以明胶为分散剂,通过葡萄糖-水合肼两步法液相化学还原Cu SO4·5H2O制备超细铜粉,并对产物进行X射线衍射(XRD)、粒度分布、扫描电子显微镜(SEM)的表征。XRD分析表明水合肼浓度达到4.8mol·L-1时,两步还原法制得的超细铜粉颗粒中不再含氧化亚铜;粒度分布分析结果显示,不同温度和不同水合肼浓度对铜粉颗粒尺寸分布有很大的影响,反应温度升高铜粉粒径集中呈现上升趋势,而水合肼浓度增大铜粉粒径集中呈现下降趋势;SEM表明随着明胶加入量的增多,铜粉的粒径先减小后增大。     

膜生物反应器处理酱油废水的中试研究

采用一体式好氧膜生物反应器( MBR)工艺处理实际酱油废水.考察了MBR对酱油废水的处理效果,并讨论了工艺参数对处理效果的影响.进水采用广东某酱油厂综合废水处理工艺的厌氧池出水,COD 500～800 mg· L-1、氨氮质量浓度为200 mg· L-1左右、色度为600～700倍、浊度为100 NTU左右.运行工艺参数:水温≥20℃、DO质量浓度≥2.5 mg·L-1、MLSS为8 000 mg·L-1、水力停留时间48 h、污泥停留时间120d.试验结果表明,在系统稳定运行后,使用膜生物反应器工艺处理酱油废水能达到良好的效果.出水COD、氨氮、色度分别为:≤90 mg·L-1、≤10mg· L-1、40倍左右,平均去除率分别为87.8％、95.94％、93.8％.对浊度的去除率能达到99％,出水水质稳定.     

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.     

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.     

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。