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1.
马旭光 《广州化工》2015,(6):83-84,152
采用离子交换法制备了具有Keggin结构杂多阴离子层状材料LDH-[Si W11Cr(H2O)O39]5-。以层状材料LDH-[Si W11Cr(H2O)O39]5-为催化剂,研究了在紫外光照射下,对甲基紫的光催化降解,讨论了溶液的酸度、溶液的初始浓度以及催化剂投加量等对甲基紫溶液脱色效果的影响。结果表明:当催化剂加入量为3 mg,甲基紫的初始浓度为15 mg/L,溶液p H为6时,脱色率可达到82.53%。  相似文献   

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用自制的Si W11Cr/PANI为光催化剂,以龙胆紫溶液模拟工业染料废水,研究了Si W11Cr/PANI的光催化降解性能,实验主要考察了催化剂的用量、染料溶液的初始浓度、染料溶液的p H等对龙胆紫溶液脱色率的影响。实验表明,光催化降龙胆紫的最佳条件是:催化剂用量3 mg,p H值为3,染料溶液初始浓度为15 mg/L,紫外灯光照170 min,脱色率为97.97%。  相似文献   

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以SiW_(11)Cr/GO/PANI为吸附剂,研究了其对模拟染料废水甲基橙溶液的吸附性能,考察了甲基橙溶液的初始pH值、SiW_(11)Cr/GO/PANI催化剂的用量、甲基橙溶液的初始浓度等对催化剂吸附率和去除率的影响,结果表明:催化剂投加量为10mg、溶液的pH值为6、甲基橙溶液的浓度为15mg/L,染料甲基橙的最大去除率能达到95.11%。  相似文献   

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合成了杂多酸/氧化石墨烯复合材料β_3-SiW_(11)Ni/GO。用红外光谱、紫外光谱和X-射线粉末衍射仪对样品进行了表征,并对催化剂投入量、染料的初始浓度、溶液的pH等条件进行探究,确定了反应的最佳条件。结果表明,亚甲基蓝被β_3-SiW_(11)Ni/GO吸附的最佳条件为pH 8、催化剂用量为80 mg/L、染料浓度为15 mg/L,最大吸附率达89.80%,最大吸附量可达111.3 mg/g。  相似文献   

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以SiW12/PANI/TiO2为光催化剂。在紫外灯辐射下,研究了模拟染料废水甲基紫溶液的光催化降解的反应,考察了催化剂投加量、染料浓度、溶液的pH值对甲基紫降解率的影响。结果表明,甲基紫溶液光催化降解的最佳条件为:pH=5,SiW12/PANI/TiO2催化剂投加量为0.0125 g,浓度为5 mg/L,经30 W紫外灯照射90 min后,其降解率为90.69%。  相似文献   

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研究了复合材料α-SiMo_(11)Mn/GO对龙胆紫在不同pH值,不同催化剂用量及不同初始浓度的吸附率的影响。确定了最佳反应条件。结果表明,α-SiMo_(11)Mn/GO吸附龙胆紫的最佳条件为:pH值=9,龙胆紫溶液15 mg/L,催化剂用量5 mg,最大吸附速率80.52%,最大吸附量70.23mg/g。  相似文献   

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以PW11/PANI/Ti O2为光催化剂,研究了不同条件对亚甲基蓝光催化降解效果的影响,如改变亚甲基蓝溶液的起始浓度、调节溶液的起始p H值和催化剂的用量等。结果表明,亚甲基蓝溶液光催化降解的最佳条件为染料的起始质量浓度为10 mg/L,p H值为3,催化剂的最佳用量为7.5mg,可达90.12%的脱色率。该催化剂对亚甲基蓝染料的降解为一级动力学反应。  相似文献   

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马荣华  韩冰洁  刘冰  杨丽  张秀平 《广州化工》2013,41(8):69-70,148
以取代型杂多酸盐Na7Co(H2O)CrW11O39.14H2O为光催化剂。在紫外灯辐射下,研究了模拟染料废水孔雀石绿的光催化降解的反应,讨论了催化剂投加量、孔雀石绿的初始质量浓度、溶液的pH值等对孔雀石绿降解率的影响。结果表明,孔雀石绿溶液光催化降解的最佳条件为:pH值为2,催化剂投加量为2 mg,孔雀石绿的初始质量浓度为5 mg/L,经15 W紫外灯照射1 h后,其降解率为90.94%。  相似文献   

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将天然硅藻土与Hummers法制得的氧化石墨烯进行复合,得到氧化石墨烯/硅藻土复合材料,并研究了该复合材料对亚甲基蓝染料的吸附过程。复合材料与亚甲基蓝染料处理时间为30min,初始溶液pH=8时,亚甲基蓝的脱色率和吸附量可达最大;吸附剂质量浓度为2mg/mL时,脱色率可达95%以上。氧化石墨烯/硅藻土吸附亚甲基蓝的过程可以用二级动力学模型很好地拟合,说明吸附速率对初始浓度较为敏感,主要为化学吸附。吸附等温线符合Freundlich等温线模型,已测得亚甲基蓝在氧化石墨烯(GO)/硅藻土上的最大吸附量为125mg/g。  相似文献   

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以自制氧化石墨烯(GO)和阿拉伯胶(GA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为原料,采用一步水热反应法制备了GO/GA-g-PAMPS新型复合水凝胶,利用FTIR、XRD、SEM对复合水凝胶结构进行了表征。研究了GO浓度、溶液pH、染料初始浓度、吸附时间、吸附温度对阳离子染料亚甲基蓝(MB)和结晶紫(CV)吸附性能的影响。结果显示:水凝胶对阳离子染料具有较好的吸附效果,在GO浓度为0.3mol/mL,凝胶用量为0.05g,溶液pH为7,温度为50℃,染料初始浓度为200mg/L时,凝胶对MB和CV的吸附量和吸附率分别为395.68、381.70mg/g和98%、96%。凝胶经过5次循环使用后,对MB和CV的吸附率仍能达到82.6%和81.2%。吸附等温线和动力学研究表明,凝胶对MB吸附更符合Freundlich模型,对CV的吸附更符合Langmuir模型,准二级动力学模型能更好地描述两种阳离子染料的吸附过程。热力学研究表明水凝胶对两种染料吸附是自发、吸热和混乱度增加的过程。  相似文献   

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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.  相似文献   

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2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
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。  相似文献   

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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.  相似文献   

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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.  相似文献   

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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.  相似文献   

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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.  相似文献   

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