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1.
以活性炭纤维(ACF)为载体,采用溶胶-凝胶法制备活性炭纤维负载二氧化钛复合材料(TiO_2/ACF)。以甲基橙为模型化合物,研究TiO_2/ACF对染料废水的光催化降解活性,考察光照时间、溶液初始浓度、pH值、光强、重复使用次数等因素对甲基橙溶液去除率的影响。结果表明,TiO_2/ACF对甲基橙废水具有较好的光催化降解活性和重复利用性,ACF吸附和TiO_2光催化产生了协同作用。  相似文献   

2.
为了去除碱性水溶液中的染料,采用纳米二氧化锰负载钴锰(Co(Ⅱ)-Mn(Ⅱ)-MnO_2)催化K_2S_2O_8/NaHCO_3氧化降解染料。对Co(Ⅱ)-Mn(Ⅱ)-MnO_2催化剂进行形貌和结构表征。考察了溶液初始pH值、反应温度、催化剂投加量、甲基橙(MO)、过硫酸钾摩尔比及碳酸氢钠浓度等因素对Co(Ⅱ)-Mn(Ⅱ)-MnO_2催化氧化MO的影响,并对MO氧化过程结构变化进行分析。实验结果表明:在优化条件下Co(Ⅱ)-Mn(Ⅱ)-MnO_2催化MO(40mg/L)的降解率达到82.61%,MO降解反应动力学为一级反应。该体系适合处理中性和弱碱性MO废水。  相似文献   

3.
活性炭在三维电极法处理染料废水中的应用   总被引:1,自引:0,他引:1  
采用活性炭作为自制三维电极反应器中的第三极,并用此电极反应器对甲基橙模拟染料废水的降解进行了实验研究。重点讨论了电压、电解质浓度以及溶液pH等因素对CODCr去除率和甲基橙去除率的影响。研究结果表明:活性炭作为第三极的三维电极反应器对甲基橙模拟染料废水进行降解,甲基橙浓度去除率到达90%,CODCR去除率达到80%。并由此展望了活性炭在三维电极处理染料废水的应用前景。  相似文献   

4.
TiO_2柱撑蒙脱土的制备及其光催化性能的研究   总被引:1,自引:1,他引:0  
采用TiCl4在 HCl中的水解制备TiO2柱撑蒙脱土(TiO2-PILM)纳米光催化材料,通过X射线衍射和红外光谱对其进行了表征.考察了甲基橙的初始浓度、甲基橙溶液、pH值对光催化降解效果的影响.结果表明,TiO2-PILM具有大的晶面间距,TiO2-PILM 对甲基橙有较好的光催化活性,吸附动力学数据很好地符合Lagergren二级速率方程,在甲基橙初始浓度为10mg/L、投样量为0.02g、在酸性或碱性条件时,TiO2-PILM对甲基橙的降解率较高.  相似文献   

5.
壳聚糖/Ni-TiO2复合絮凝剂对印染废水的处理研究   总被引:2,自引:0,他引:2  
利用溶胶-凝胶法制备壳聚糖/Ni-TiO2复合絮凝剂,去处理模拟印染废水。用可见分光光度测定法对甲基橙的含量进行了测定,考察了壳聚糖/Ni-TiO2复合絮凝剂投加量、反应时间、反应温度、pH值对废水处理效果的影响。结果表明:在超声波频率为50kHz时,甲基橙溶液初始浓度为25mg/L,溶液pH=6,壳聚糖/Ni-TiO2复合絮凝剂的加入量为0.1g,时间60min,温度为40℃,甲基橙溶液脱色率到达到95.0%以上。同时,壳聚糖/Ni-TiO2复合絮凝剂处理甲基橙溶液时,不仅有吸附作用的存在,同时还有光催化降解的作用。  相似文献   

6.
采用Sol-gel法制备了纳米TiO_2/改性硅藻土复合材料,并用于处理直链烷基苯磺酸钠(LAS)废水,以COD_(Cr)为评价指标,考察了催化剂的投加量、水温、催化时间、废水初始pH值和初始浓度等因素对降解性能的影响,分析了催化降解的动力学。结果表明,初始COD_(Cr)为425.9mg/L的LAS废水,当调节废水pH=5.0,催化剂投加量为4.0g/L时,10W紫外光催化反应6h废水中COD_(Cr)降解率达到84.46%;水温升高不利于降解率的提高,废水初始浓度的降低或稀释后COD_(Cr)降解率明显提高,在酸性条件下催化效果要优于中性和碱性;添加1mL 30%H_2O_2,COD_(Cr)降解率可提高10%~15%;LAS废水降解COD_(Cr)的反应符合Langmuir-Hinshelwood动力学模型。  相似文献   

7.
质子化交联壳聚糖对甲基橙的吸附研究   总被引:2,自引:0,他引:2  
杨炳超  刘倩  霍杰  黄瑞华 《功能材料》2013,44(3):376-379
研究了吸附剂投加量、甲基橙初始浓度、pH值、吸附时间等条件对甲基橙脱色效果的影响。结果表明,在质子化壳聚糖用量为3.6g/L条件下,对质量浓度低于200mg/L甲基橙溶液的吸附率不低于90%。拟二级动力学模型能很好地描述其吸附过程;吸附等温线符合Langmuir模型。质子化壳聚糖在较宽的pH值范围内对甲基橙具有较好的脱色效果,可提高壳聚糖的利用价值。  相似文献   

8.
膨胀石墨电极用于电化学氧化降解甲基橙模拟废水   总被引:1,自引:0,他引:1  
采用具有优良导电能力的膨胀石墨(EG)作为阳极材料,通过电化学氧化降解甲基橙模拟废水.当废水pH值为2.0,电流密度为13mA·cm-2,电解质浓度为0.1 mol· dm-3,电解时间为20 min时,甲基橙模拟废水的脱色率达到98.6%,COD去除率为58.5%.该降解过程基于化学吸附和电化学氧化,亦即,甲基橙分子首先通过EG表面的-OH键吸附在EG表面,然后通过电化学氧化降解.结果表明:EG是一种处理染料废水的优良材料.  相似文献   

9.
为了更好地了解炭基材料与铁氧化物复合光Fenton处理染料的机理,开发出更多的炭基材料与高级氧化技术相结合的复合技术,拓展复合材料的用途,以活性炭纤维为载体,硝酸铁为铁源,硝酸锰为锰源,柠檬酸为络合剂,采用溶胶-凝胶法合成了新型非均相Fenton催化剂。利用SEM、XRD表征手段对材料进行了分析,并使用复合材料对甲基橙进行了光Fenton催化实验。探讨了新型催化剂在模拟太阳光下对甲基橙染料的降解情况,考察了过氧化氢的含量、pH值、Mn氧化物对甲基橙降解的影响,分析了其反应机理,研究了其循环使用的稳定性。结果表明:溶胶-凝胶法可以在ACF表面成功负载Fe和Mn的氧化物;复合光Fenton催化剂对染料的降解属于光敏化机理;在可见光下,随着过氧化氢浓度从0mmol/L到20mmol/L的提高,其降解速率逐渐增大,后期增加缓慢;在过氧化氢浓度为15mmol/L,可见光照射下,材料在溶液初始pH为3至9的范围,催化剂浓度2.4g/L,对100mg/L染料的去除都有70%以上的去除效果;锰的添加对脱色效果具有促进作用;重复使用材料5次,其脱色效果仍然保持在90%以上。  相似文献   

10.
采用黑索金为可爆药剂,用爆轰法制备出了类球形混晶纳米TiO2粉体,并对合成的纳米TiO2粉末进行了表征。以甲基橙为研究对象,紫外灯为光源,研究了甲基橙初始浓度、纳米TiO2用量、甲基橙溶液初始pH值、超声分散和光照时间对甲基橙降解率的影响。研究表明,所制备的纳米TiO2为锐钛矿、板钛矿和金红石组成的混晶体,平均粒度约为18nm。在氧化钛浓度固定的条件下,甲基橙溶液初始浓度越高降解率越低。随着氧化钛加入量的增加,甲基橙溶液的降解率先增大后减小,而氧化钛的加入量超过40.0mg/L后,甲基橙溶液的降解率又呈升高的趋势。超声波分散的纳米氧化钛的表观反应速率明显高于未经超声波分散的氧化钛的表观反应速率。随着光催化时间的延长,光转化率逐渐升高。  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

13.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

14.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

15.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

16.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

17.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

18.
Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.  相似文献   

19.
As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.  相似文献   

20.
TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.  相似文献   

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