Fe~(3+)对厌氧产甲烷体系的影响及生物有效性研究

通过间歇实验建立厌氧产甲烷体系,研究不同Fe~(3+)含量对厌氧颗粒污泥消化过程的影响。结果表明,当Fe~(3+)的质量浓度为0~40 mg/L时,甲烷产量随着Fe~(3+)含量增加而增加,加快了微生物对挥发性脂肪酸(VFAs)的利用;高含量Fe~(3+)(质量浓度50~100 mg/L)抑制厌氧产甲烷过程。当Fe~(3+)的质量浓度在40 mg/L时,获得最大甲烷气体体积1.578 L,较对照提高了36.32%。利用Gompertz模型拟合可得,最大产甲烷产率和甲烷潜在产量分别达到11.06m L/h和1.640 L,延滞时间缩短了3.98 h。脱氢酶和F420的质量浓度分别为27.23μg/L和54.85μg/L。且Fe~(3+)的质量浓度在40 mg/L时,污泥对Fe~(3+)水溶态和离子交换态利用率分别提高了90.36%和54.55%,总利用率达25.32%,生物有效性得到提升。     

DVD-Ag电极阳极溶出伏安法测定枸杞子中铅和镉残留

建立了利用DVD-Ag电极阳极溶出伏安法同时快速测定铅和镉的方法,并考察了I^-对电极上的铅和镉溶出分析的影响。利用该方法测定了枸杞子中铅和镉的残留含量。结果表明,优化实验条件下,在5～50μg/L浓度范围内,Pb-对电极上的铅和镉溶出分析的影响。利用该方法测定了枸杞子中铅和镉的残留含量。结果表明,优化实验条件下,在5～50μg/L浓度范围内,Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的溶出峰电流与Pb(2+)的溶出峰电流与Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的浓度呈线性相关,相关系数分别为0.992 3和0.995 3,Pb(2+)的浓度呈线性相关,相关系数分别为0.992 3和0.995 3,Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的检出限分别为0.2μg/L和2.6μg/L(S/N=3)。对该方法进行了方法学考察,包括精密度、稳定性和回收率,结果均符合相关要求。枸杞子中Pb(2+)的检出限分别为0.2μg/L和2.6μg/L(S/N=3)。对该方法进行了方法学考察,包括精密度、稳定性和回收率,结果均符合相关要求。枸杞子中Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的残留含量测定结果与经典的电感耦合等离子体质谱法(ICP-MS)一致性较好,表明该方法可用于枸杞子中铅和镉的残留量的检测。     

磁性生物炭对镉、砷的吸附效果研究

用Fe_3O_4对谷壳生物炭进行改性得到磁性生物炭。利用SEM、XRD对磁性生物炭进行表征,并通过响应面优化和共吸附实验探究该生物炭在共吸附系统中对As~(3+)和Cd~(2+)的吸附性能。结果表明,在pH为5.0、镉(砷)初始质量浓度分别为10 mg/L、吸附剂质量浓度为1 g/L时,镉和砷去除率达到最大。在共吸附实验中,As~(3+)和Cd~(2+)共存时,Cd~(2+)质量浓度大于20 mg/L时会抑制生物炭对As~(3+)的吸附,10 mg/L As~(3+)与生物炭达到平衡后可以使50 mg/L Cd~(2+)的吸附量由17.44 mg/g增加到31.91 mg/g,说明砷和镉之间存在协同作用,该协同作用是由于镉、砷与四氧化三铁形成了B型三元表面配合物,增大了镉的吸附量。     

钙对陶瓷平板膜生物反应器膜污染的影响研究

通过配制Ca~(2+)的质量浓度分别为50、120、230、540、730 mg/L的进水,考察不同Ca~(2+)含量对陶瓷平板膜生物反应器(C-MBR)膜污染的影响。实验数据表明,Ca~(2+)的质量浓度为230 mg/L时,TP的去除率比Ca~(2+)的质量浓度为50 mg/L时高30%左右,TMP上升速率比其它Ca~(2+)含量下低约为37%,膜通量下降趋势比其它Ca~(2+)含量下高约为27%。同时,在Ca~(2+)的质量浓度为230 mg/L时,由于Ca~(2+)强化了生物絮凝作用,故污泥混合液中的SMP及EPS较其它Ca~(2+)含量下低。     

磁性氧化石墨烯材料的制备及其对重金属离子的吸附研究

采用一步共沉淀法,以FeCl_2·4H_2O、FeCl_3·6H_2O和氧化石墨烯为原料,在碱性条件下制备氧化石墨烯/四氧化三铁的磁性复合材料(MGO),考察pH、时间和吸附温度等对MGO吸附Cu⁽²⁺⁾的影响。结果表明,MGO对Cu(2+)的影响。结果表明,MGO对Cu⁽²⁺⁾的最佳吸附条件:20 mL浓度为200 mg/L、pH=5.5的Cu(2+)的最佳吸附条件:20 mL浓度为200 mg/L、pH=5.5的Cu⁽²⁺⁾溶液,加入MGO 20 mg,吸附温度30℃,吸附时间150min,最大吸附容量为61.4 mg/g,Cu(2+)溶液,加入MGO 20 mg,吸附温度30℃,吸附时间150min,最大吸附容量为61.4 mg/g,Cu⁽²⁺⁾的去除率为98.1%。MGO吸附Cu(2+)的去除率为98.1%。MGO吸附Cu⁽²⁺⁾符合准二级动力学模型。     

Ca~(2+)、Mg~(2+)对剩余污泥自培养产酶影响

为提高剩余污泥投加复合菌后产水解酶效果,探讨了添加Ca⁽²⁺⁾、Mg(2+)、Mg⁽²⁺⁾对剩余污泥自培养产酶中污泥水解的影响。结果表明,未加Ca(2+)对剩余污泥自培养产酶中污泥水解的影响。结果表明,未加Ca⁽²⁺⁾、Mg(2+)、Mg⁽²⁺⁾的空白组,蛋白酶和淀粉酶活力均呈现第1 d上升至最大值,后持续降低的趋势。添加0.03 mol/L Ca(2+)的空白组,蛋白酶和淀粉酶活力均呈现第1 d上升至最大值,后持续降低的趋势。添加0.03 mol/L Ca⁽²⁺⁾组的蛋白酶活力第1 d快速升至246.14 U/mL,后持续上升,并在第7 d酶活力达最大值340.07 U/mL,蛋白酶活力最大值较空白组增加了53.94%;淀粉酶活力在第1 d快速升至351.02 U/mL后快速下降,第7d酶活力为70.79 U/mL,淀粉酶活力最大值较空白组增加了51.93%,表明添加0.03 mol/L Ca(2+)组的蛋白酶活力第1 d快速升至246.14 U/mL,后持续上升,并在第7 d酶活力达最大值340.07 U/mL,蛋白酶活力最大值较空白组增加了53.94%;淀粉酶活力在第1 d快速升至351.02 U/mL后快速下降,第7d酶活力为70.79 U/mL,淀粉酶活力最大值较空白组增加了51.93%,表明添加0.03 mol/L Ca⁽²⁺⁾可以提高灭菌污泥自培养产酶效果。而添加0.06 mol/L Ca(2+)可以提高灭菌污泥自培养产酶效果。而添加0.06 mol/L Ca⁽²⁺⁾组酶活力呈下降趋势,表明高浓度Ca(2+)组酶活力呈下降趋势,表明高浓度Ca⁽²⁺⁾对产酶有抑制作用。添加0.03 mol/L或0.06 mol/L Mg(2+)对产酶有抑制作用。添加0.03 mol/L或0.06 mol/L Mg⁽²⁺⁾,不能提高产酶效果,但能维持酶活力稳定。添加合适浓度Ca(2+),不能提高产酶效果,但能维持酶活力稳定。添加合适浓度Ca⁽²⁺⁾、Mg(2+)、Mg⁽²⁺⁾能强化剩余污泥产酶过程中污泥水解效果,促进污泥上清液中有机物水解。     

菜芙蓉花体外抗氧化活性部位的研究

采用连续提取法对菜芙蓉花乙醇提取物进行分离,得到石油醚相、乙酸乙酯相、正丁醇相和萃余水溶物4个不同极性部位。以还原力和清除羟自由基(·OH)、超氧阴离子自由基(O_2~-·)、DPPH自由基(DPPH·)能力为评价指标筛选其活性部位,并对活性最强部位进行体外小鼠红细胞溶血、肝组织匀浆和肝线粒体丙二醛(malondialdehyde,MDA)生成量及其肿胀度的研究。结果表明:菜芙蓉花提取物不同极性部位对自由基的清除能力表现为DPPH·O_2~-··OH,其中乙酸乙酯部位(Ethyl acetate Extract,EA)对三者清除能力最强,半清除浓度EC50分别为3.52、44.96、376.87μg/m L。在体外脂质过氧化抑制作用研究中,EA能够显著抑制小鼠红细胞溶血(p0.05),在50~500μg/m L范围内能抑制肝组织匀浆和肝线粒体MDA的生成,并有效抑制小鼠肝线粒体的肿胀,具有量效关系。     

超高效液相色谱-串联质谱法测定水体中稻瘟灵和吡唑醚菌酯

采用高效液相色谱-串联质谱法建立了水体中稻瘟灵和吡唑醚菌酯的检测方法,以0.2%甲酸水溶液-甲醇为流动相,以电喷雾(ESI+)模式测定,多离子反应监测(MRM)模式扫描,外标法定量稻瘟灵和吡唑醚菌酯在0.000 1~0.05 mg/L均具有良好的线性关系,最低检测浓度分别为0.159μg/L和0.108μg/L。在0.000 2~0.02 mg/L进行添加回收试验,结果表明,2种有效成分平均回收率为82.86%~96.84%,相对标准偏差为2.14%~6.33%。     

抑制Fe~(2+)-H_2O_2-孔雀石绿褪色光度法测定挂面中的丙二醛

Fe~(2+)-H_2O_2在酸性介质中氧化孔雀石绿反应褪色,但丙二醛加入Fe~(2+)-H_2O_2-孔雀石绿组成体系抑制褪色反应,且体系的吸光值随着丙二醛的含量增加呈线性增长。据此原理建立可见光分光光度法测定溶液中丙二醛的含量。在最优实验条件下,波长λ=620 nm,175μL硫酸、40μL硫酸亚铁、400μL孔雀石绿,140μL过氧化氢,反应时间为15 min、反应温度35℃时,线性回归方程为:ΔA620 nm=0.197 1ρ-0.014 3(ρ:μg/mL),线性范围为0.125~3.50μg/mL,检出限(3S/K)为0.068μg/mL,该方法分析挂面中的丙二醛的含量,回收率在95.7%~107.1%之间,分析方法可行。     

铁板电絮凝同时去除氟和镉

采用改进平行单极电絮凝连接方式进行F~-和Cd~(2+)去除效果的研究。结果表明,当初始F~-和Cd~(2+)的质量浓度分别为5 mg/L和0.5 mg/L时,优化的工况条件为:初始pH=11、电流密度9.8 m A/cm~2、NaCl的质量浓度为0.75 g/L、极板间距0.5 cm、电解时间55 min。此时F~-、Cd~(2+)去除率分别大于89.12%、99.99%;出水F~-、Cd~(2+)的质量浓度分别为0.54 mg/L、5μg/L,均符合GB 5749-2006要求。处理费用为5.78～8.73元/m~3。傅立叶变换红外光谱仪和X射线衍射仪分析表明,F~-和Cd~(2+)的去除主要是通过吸附沉淀的方式被去除的。该方法污泥量少、易脱水、高效节能等优势。     

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.     

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。     

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.