固定化EM菌处理炼油废水的研究

探讨了两种固定EM菌的方法及两种固定化微生物小球的物理性质,通过正交实验,研究炼油废水的pH、投菌量、处理时间3个因素对石油类物质,氨氮去除率的影响。结果表明:①白球在pH为5、小球投加量(投菌量)为40个、处理时间为2 d时,固定化EM菌对炼油废水的石油类物质和氨氮的去除率分别为40.17%和49.51%;②黑球在pH为6、小球投加量为40个、处理时间为3 d的条件下,固定化EM菌对炼油废水的石油类物质和氨氮的去除率分别为52.26%和46.97%。     

氨氮菌处理焦化废水中氨氮的实验研究

文章采用专门的氨氮菌处理焦化废水中的氨氮和COD,处理流程为:原水先经MAP法预处理,再用氨氮菌处理,出水再经絮凝处理。MAP法即在pH为9.75时,按照最佳配比:MgC12 6H2O∶NH3-N∶Na2HPO4 12H2O=1.2∶1∶1投加药剂,原水氨氮去除率可达83.58%。氨氮菌处理时,最佳氨氮菌为AQ-01型,最佳实验条件为pH 8.0,温度25℃,当加菌量200 mL时,连续曝气25 h后,氨氮去除率达75.6%,COD去除率达97.2%。絮凝剂选择聚合硫酸铁,经絮凝处理最终出水氨氮值达到国家一级排放标准。     

温度/pH双响应硝化菌凝胶球的制备及特性研究

采用包埋法制备了粒径均匀的海藻酸钙(CA)硝化菌小球,并用不同浓度的NaCl溶液处理CA硝化菌小球来改善其扩散传质性能,以N-异丙基丙烯酰胺(NIPAAm)、丙烯酸(AA)为单体材料,形成温度/pH响应层,制得一种新型温度/pH双响应硝化菌凝胶小球。以NH4+?N为指示物考察不同制备条件下硝化菌凝胶小球的氨氮去除性能及对温度、pH的敏感特性,并将其应用于实际废水的脱氮处理。结果表明,经浓度为0.3%的NaCl溶液改性后的CA硝化菌小球的扩散传质性能最佳;15 mL温度响应溶液中NIPAAm为200 mg、MBA为4 mg,10 mL pH响应溶液中AA为200 mg、MBA为4 mg时双响应硝化菌小球的氨氮去除性能最好;当温度低至4℃时,氨氮去除率可达29.45%,当pH为9时,氨氮去除率仍可达35.48%。双响应硝化菌凝胶小球具有良好的温度、pH敏感特性,对实际废水中氨氮的去除也具有良好效果,有利于提高低温及碱性条件下硝化菌的硝化效果。     

固定化硝化菌去除污水中氨氮工艺参数优化

为优化固定化硝化菌去除氨氮的工艺条件,采用正交试验方法,考察了固定化微球投加量、通气速率、反应温度和pH值4个因素对氨氮去除效果的影响,获得固定化细菌对模拟废水中氨氮的最优去除条件。结果表明:当固定化微球投加量为200 g/L,反应温度为40℃,体系pH值为9.0,通入空气表观气速为1.5 L/(min·L)时,氨氮去除率最高。4种因素的影响程度依次为pH值固定化微球投加量反应温度表观气速。在此最优条件下,当初始氨氮质量浓度为100 mg/L时,可使其去除率达97%以上。     

硅藻土处理低浓度氨氮废水效果研究

采用天然硅藻土处理低浓度氨氮废水,运用单因素试验法考察了硅藻土投加量、废水pH值和搅拌时间对氨氮去除率的影响,研究结果显示:在其对地表水氨氮(0.277 mg/L)的处理中,当硅藻土投加量为40 mg/L、pH值为7、搅拌时间为25 min时,处理效果最佳,氨氮去除率可达64.5%;在其对咸阳印染废水氨氮(13.4 mg/L)的处理中,当硅藻土投加量为800 mg/L、 pH值为8、搅拌时间为25 min时,处理效果最佳,氨氮去除率可达45.3%;在其对福建印染废水氨氮(26.76 mg/L)的处理中,当硅藻土投加量为2 500 mg/L、 pH值为7、搅拌时间为35 min时,处理效果最佳,氨氮去除率达到51.6%。硅藻土适用于低浓度氨氮废水的处理。     

固定化菌藻小球去除猪场废水中氨氮的研究

菌藻共生体系对猪场废水中的氨氮去除效果良好,但游离的菌藻易流失,将菌藻进行有效粘附是目前该体系的研究热点。以聚乙烯醇—海藻酸钠为载体,采用包埋法将光合细菌和混合藻液制备成固定化菌藻小球,考察其物理特性及最优制备条件,并探讨其对猪场废水中氨氮的去除效果。实验结果表明,固定化菌藻小球的最佳制备条件为：海藻酸钠投加量0.14%(m/V)、光合细菌包埋量1.18×10¹⁰ cfu/mL、包埋时间3.46 h。对于初始氨氮浓度为500mg/L的猪场废水,在不调节废水pH的条件下,经过10 g/L的固定化菌藻小球处理12 d后,氨氮去除率高达93.3%。     

低浓度氨氮废水的厌氧氨氧化研究

采用污泥混合接种的方法，利用UASB反应器进行厌氧氨氧化菌混培物的培养与驯化，在温度为30℃、pH为7．5的条件下反应器连续运行了210d。当含氮模拟废水进水NH30N浓度和NO2^--N浓度分别为3-5mmol／L和4～6mmol／L时，其最大去除率分别达68．0％和95．1％。扫描电镜结果表明，厌氧氨氧化菌混培物以形状不规则的短杆菌为主。     

磷酸铵镁法处理高浓度氨氮废水的研究

研究采用磷酸铵镁沉淀法,以MgO和Na2HPO4·12H2O为沉淀剂对4 028 mg/L的模拟高浓度氨氮废水进行处理,考察了pH和药剂配比对磷酸铵镁法沉淀效率的影响,获得磷酸铵镁法对高浓度氨氮废水的最佳处理条件为pH=9.5、MgO与Na2HPO4·12H2O药剂以及废水中氨氮物质的量比(n(Mg)∶n(P)∶n(N)]为2.4∶0.95∶1.在最佳条件下,利用磷酸铵镁法对模拟高浓度氨氮废水中的氨氮去除率为93.6%,对实际工业废水中的氨氮去除率为90%.     

鸟粪石沉淀法处理高氨氮稀土废水

以贺州市某稀土冶炼厂萃取分离稀土元素时产生的高氨氮废水为研究对象,进行鸟粪石沉淀法脱氮试验研究,设计4因素3水平正交试验,确定影响因素大小,得到适宜反应条件组合,进行pH、n(Mg):n(N)、n(P):n(N)、反应时间等4因素优化试验,考察各因素对于氨氮去除率及剩余总磷质量浓度的影响。结果显示,对于氨氮去除率与剩余TP质量浓度,影响因素依次为pH、反应时间、n(Mg):n(N)、n(P):n(N)。在pH=9.3,n(Mg):n(N):n(P)=2.2:1:2,反应时间20 min,氨氮质量浓度由4 420 mg/L降低至1 440 mg/L,氨氮去除率可达到67.40%,剩余TP质量浓度为0.9mg/L;较高的Ca2+质量浓度会影响MAP法对氨氮去除率,但有利于降低出水TP质量浓度;过长的反应时间会破坏已形成的MAP沉淀体系。     

光合混菌生物阳极MFC对高浓度淀粉废水的处理

以光合混菌PB-Z为阳极菌,在室温、自然光照和静置的环境下以高浓度淀粉废水为基质,探讨微生物燃料电池(MFC)的处理效果,并通过更换氮源、优化氮源浓度和添加Ca2+的方式进行改善。结果表明,PB-Z在初试实验中,COD去除率为61.84%,TN去除率为62.89%。更换氮源、优化氮源浓度和添加Ca2+都可以提升其COD的去除率,确定了最佳氮源为氯化铵,最佳氨氮浓度为6 mmol/L和最佳Ca2+质量浓度为30 mg/L,优化后的COD去除率为94.64%,氨氮去除率为70.13%,为MFC处理淀粉废水的工业化提供了实验基础。     

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.     

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.     

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。     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。