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1.
研究了Cu2+、Ag+和AuCl-4在碱式纤维素基磁性聚偕胺肟树脂(BMAO)上的吸附行为.实验结果表明,吸附速度受粒内扩散所控制.测得吸附起始速度的顺序是Ag+>AuCl-4>Cu2+,认为与水合离子尺寸有关.根据扫描电镜观察和吸附动力学研究结果,提出并讨论了吸附/交换和氧化还原反应机理.  相似文献   

2.
利用活化后硅胶作为载体,Cu~(2+)为模板离子,γ-脲基丙基三甲氧基硅烷作为功能单体和偶联剂,以二甲基丙烯酸乙二醇酯和偶氮二异丁腈为交联剂和引发剂合成了硅胶活化铜离子表面印迹材料Cu(II)-IIP,并以此作为吸附剂进行静态吸附实验。结果表明,Cu(II)-IIP对于Cu(II)的吸附过程可用Langmuir等温吸附模型来描述,其吸附行为符合准2级动力学方程,即对Cu(II)的吸附过程以单层吸附为主。Cu(II)-IIP对Cu(II)的吸附在50 min可达到吸附平衡。当水中Cu(II)初始质量浓度为50 mg/L、p H为6、温度为40℃吸附平衡时吸附量达到最高,对Cu(II)最大吸附容量可达76.29 mg/g。  相似文献   

3.
麻晓霞  裴阳阳  马玉龙  蒲涛  雷云 《硅酸盐通报》2017,36(12):4117-4121
以Cu(NO3)2、ZnCl2、NaOH为主要原料,蒙脱石(MMT)作为载体,制备Cu2+/ZnO-MMT抗菌材料,并对其结构、表面性质和抑菌性能进行表征.结果表明,Cu2+/ZnO-MMT对大肠杆菌和金黄色葡萄球菌均具有较强的抑菌活性.以大肠杆菌为试验菌种,研究了所制材料的杀菌机理,首先大肠杆菌被吸附到蒙脱石表面,然后细菌细胞质膜被所载的Cu2+和ZnO损伤,使胞内溶物外流,最终细菌死亡.  相似文献   

4.
地质聚合物是活性铝硅酸盐矿物在碱激发作用下形成的一类无机胶凝材料,除可替代传统硅酸盐水泥用作建筑材料外,作为吸附材料用于废水处理也显示出广阔前景.由于原材料种类和制备工艺的不同,地质聚合物基吸附材料对有害物质的去除能力差异显著.介绍了地质聚合物基吸附材料凝胶法、水热法和焙烧法三种制备方法,综述了不同物理形态的地质聚合物基吸附材料及其微观结构和吸附能力之间的关系,阐述了吸附条件(pH值、吸附时间、温度和初始离子浓度)对地质聚合物吸附能力的影响,总结了吸附动力学、热力学和吸附等温线模型方面的研究进展,提出了地质聚合物基吸附材料未来的研究方向.  相似文献   

5.
采用直接沉淀法制备了Fe掺杂ZnO/凹凸棒石(Fe-ZnO/ATP)复合材料,评价了其在可见光条件下(>400 nm)光催化降解高浓度亚甲基蓝(MB)溶液的性能,并系统研究了ZnO负载量、Fe掺杂量和焙烧温度等对复合材料吸附性能和光催化性能的影响.结果表明,ATP的复合增强了复合材料对MB的吸附能力,MB在最佳条件下制备的Fe(0.3%)-ZnO(50%)/ATP复合材料上降解的表观反应速率常数(kapp)为4.2×10-3 min-1,反应3.5h后的降解率可达65.40%,与ZnO相比较,kapp和MB的降解率提高了2.6倍.XRD、TEM和UV-Vis-DRS的结果表明,复合材料中ATP的结构在热处理过程中基本保持不变,复合材料中ZnO的粒径明显减小,暴露了更多的活性位点.另外,Fe的掺杂可明显增强复合光催化剂对可见光的吸收,增强了对光的利用效率,从而使复合材料显示出优异的光催化活性.  相似文献   

6.
《应用化工》2022,(4):712-715
以二水合醋酸锌和浓氨水为原料,以海藻酸钠为表面活性剂,采用水热法制备纳米ZnO材料。透射电镜(TEM)和X射线衍射仪(XRD)研究表明,ZnO形貌为玉米穗状,宽度约为70nm,晶型为六方纤锌矿结构。以原子吸收光谱为检测手段,研究了纳米ZnO材料对Cu(Ⅱ)的吸附行为,结果表明,在pH值为6.8时,纳米ZnO材料对Cu(Ⅱ)的饱和吸附量为16.1mg/g,吸附过程具有Langmiur等温吸附特征。  相似文献   

7.
以二水合醋酸锌和浓氨水为原料,以海藻酸钠为表面活性剂,采用水热法制备纳米ZnO材料。透射电镜(TEM)和X射线衍射仪(XRD)研究表明,ZnO形貌为玉米穗状,宽度约为70nm,晶型为六方纤锌矿结构。以原子吸收光谱为检测手段,研究了纳米ZnO材料对Cu(Ⅱ)的吸附行为,结果表明,在pH值为6.8时,纳米ZnO材料对Cu(Ⅱ)的饱和吸附量为16.1mg/g,吸附过程具有Langmiur等温吸附特征。  相似文献   

8.
以等体积浸渍-焙烧-原位还原法制备Cu/SiO2>-ZnO催化剂,采用固定床管式反应器考察反应温度、H2与H2O2的通入量以及助剂ZnO含量对苯胺和乙二醇合成吲哚反应的影响.结果表明,反应温度325 ℃、H2流速65 Ml·min-1、H2O流速42 Ml·h-1和加入ZnO助剂质量分数为1.0%条件下,吲哚收率为91...  相似文献   

9.
伍君  段正康  李文娟  金世良 《精细化工》2013,30(9):1036-1040,1051
以氢氧化钠为沉淀剂,硝酸铜、硝酸锌、硝酸铝和硝酸氧锆为原料,采用共沉淀法制备出了用于二乙醇胺脱氢制亚氨基二乙酸的Cu/ZnO/Al2O3/ZrO2催化剂,并用物理吸附(BET)和X射线衍射(XRD)对不同种类的铜基催化剂进行了表征,探讨了ZnO和Al2O3的不同比例对催化剂性能的影响。结果表明,同时加入ZnO和Al2O3的Cu/ZnO/Al2O3/ZrO2催化剂具有大的比表面积,Cu/ZnO/Al2O3/ZrO2催化剂具有非晶态结构。该催化剂适宜的反应条件为:w(NaOH)=30%、反应温度160℃、压力1.0 MPa,二乙醇胺转化率可达100%,亚氨基二乙酸收率可达95.61%。  相似文献   

10.
以2-丙烯酰胺基-2-甲基丙磺酸和丙烯酸为原料,合成了P(AMPS-co-AA)大孔吸附凝胶,通过傅立叶红外和扫描电子显微镜对材料进行表征,探讨了对Fe3+、pb2+和Cu2+三种重金属离子的吸附性能.结果表明,凝胶对Fe3+的吸附效果最为理想,吸附容量和脱除率分别达到4.2 mmol/L和90.5%,pb2+为2.5...  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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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   

15.
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   

16.
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   

17.
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   

18.
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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