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1.
采用溶胶-凝胶法制备了沸石负载型Ce/S共掺杂TiO2光催化剂,探讨了可见光下负载型共掺杂TiO2光催化剂的光催化降解亚甲基蓝的可行性和工艺条件.研究结果表明,催化剂焙烧温度300℃,反应体系pH值为7.02时的亚甲基蓝降解效果最好.共掺杂复合光催化剂活性要好于单掺杂和不掺杂的光催化剂活性,负载型复合光催化剂具有很好的重复使用性能.  相似文献   

2.
用溶胶-凝胶法制备钒氮共掺杂TiO2光催化剂,以亚甲基蓝的降解率为评价指标,考察钒氮共掺杂TiO2光催化降解亚甲基蓝的影响因素.结果表明,钒氮共掺杂能显著提高TiO2的光催化活性;在本实验条件下,钒氮添加量(与Ti的摩尔比)分别为0.1%、10%的TiO2于600℃焙烧、投入量为3g/L、溶液pH值为4~7、超声振荡30min、光照催化氧化处理4h的条件对处理低浓度亚甲基蓝溶液效果最好.  相似文献   

3.
在TiO2的三种晶型中锐钛矿型的TiO2具有最好的光催化活性.在一定条件下用水热法制备了掺不同含量(摩尔比)Fe3+的TiO2粉末,XRD分析结果表明它是锐钛矿型TiO2(A-TiO2).研究了以该TiO2为光催化剂对甲基橙溶液进行降解.研究结果表明,在10mg/L的甲基橙溶液中加入掺Fe3+5%的A-TiO2 0.0800g,将溶液pH调为2.63后,经40W白炽灯光照射,室温下恒温磁力快速搅拌反应4h,降解率达到35.60%.  相似文献   

4.
POMs/TiO2复合催化剂光催化降解染料废水的研究   总被引:5,自引:0,他引:5  
采用溶胶-凝胶方法表面修饰TiO2制备了几种POMs/TiO2复合光催化剂,考察了催化剂在紫外光照射下对模拟染料废水(茜素红溶液)的光催化降解行为.结果表明:POMs/TiO2复合催化剂较纯TiO2光催化降解茜素红活性明显提高,其中复合催化剂Cr3OSiW12/TiO2光催化降解模拟染料废水(茜素红溶液)效果最佳.反应最佳条件:催化剂为Cr3OSiW12/TiO2,多酸质量分数为0.5%,催化剂用量为15 mg,茜素红溶液浓度为0.1mmol/L.茜素红降解质量分数可达74.6%.  相似文献   

5.
掺铁TiO2-活性炭复合材料的制备及其光催化活性   总被引:9,自引:0,他引:9  
通过浸渍法将掺铁TiO2溶胶负载到活性炭上制备掺铁TiO2-活性炭复合光催化剂材料,并对其结构特征、吸附特性、可见光光催化活性和再生性能进行研究.结果表明,掺铁TiO2-活性炭复合材料具有很大的比表面积,对有机污染物具有优越的吸附性能,而其比表面积则随着掺铁TiO2-活性炭的质量比的增大而逐渐减小.在可见光下,复合光催化剂材料由于Fe3 的引入TiO2中,对亚甲基蓝溶液具有高的光催化活性,其中经过500℃热处理的载钛量为5%(质量分数)的复合光催化剂材料的光催化活性最佳.复合光催化剂具有优越的再生性能,经再生处理可多次重复使用.  相似文献   

6.
采用溶胶-凝胶法制备了膨胀石墨负载TiO2和负载氮掺杂TiO2(N-TiO2)光催化剂,用XRD和SEM对样品进行表征,并以甲基橙溶液为目标降解物进行光催化性能的评价。结果表明:纳米TiO2可牢固地负载在膨胀石墨表面和层间,当达到吸附平衡后,煅烧温度为500℃条件下制备的膨胀石墨负载N-TiO2光催化剂在加入量为10 g/L、反应时间60 min的条件下,对初始浓度为15 mg/L的甲基橙溶液的降解率达到95.2%。  相似文献   

7.
用浸涂法以硅酸钠为粘结剂在沙子上制备了负载纳米TiO2光催化剂,在二相流化床光催化反应器中,通过处理4BS染料溶液考察了光催化剂的光催化活性和影响因素.得出最佳转化条件为, 催化剂(沙子,硅酸钠,二氧化钛)的最佳质量配比为10:1:2 ,光催化剂最适用量为20 mg,溶液中Fe3+最佳添加量为25 mg/L,在此条件下孔径0.45(40目)~0.90 mm(20目)的负载光催化剂处理20 mg/L的4BS染料溶液2 h,光催化降解率达到81.9%.结果还表明,溶液pH值为2~6时,光催化剂对4BS染料溶液的光催化降解率更高.  相似文献   

8.
纳米Bi_2O_3/TiO_2光催化剂的制备及光催化活性评价   总被引:2,自引:1,他引:1  
在超声波作用下采用水解法制备Bi2O3/TiO2复合光催化剂,以紫外灯为光源,对有机染料进行光催化降解实验,考察Bi2O3/TiO2的光催化性能.结果表明:Bi2O3与TiO2复合拓宽了催化剂对光的吸收范围,提高了TiO2的光催化活性,掺杂量(Bi2O3)为0.25%(w)复合光催化剂催化活性最高.考察了催化剂投加量、染料初始浓度、溶液pH值等因素对罗丹明B降解效果的影响,降解反应遵从假一级动力学模型,测得反应速率常数为0.0574min-1.  相似文献   

9.
以聚乙烯醇(PVA)为高分子配体,与ZnCl2在水溶液中通过配位-水解反应,制备ZnO/PVA复合纤维,并用SEM对制备的纤维进行表征.研究了ZnO/PVA复合纤维材料制备工艺与光催化降解性能的关系,得出最佳降解条件.实验结果表明,在ZnCl2溶液的浓度为0.02 mol/L、pH=8、反应温度为100℃、反应时间3h条件下,制备的ZnO/PVA复合纤维对甲基橙有较好的光催化效果.  相似文献   

10.
为考察低温醇解法制备金属离子掺杂型TiO2的光催化活性,本文以TiCl4为原料,采用低温正丁醇醇解法制备Bi掺杂的光催化剂TiO2.在紫外光照和太阳光照条件下,以亚甲基蓝溶液作为降解物研究不同铋掺杂量二氧化钛样品的催化性能.结果表明:当Bi2O3/TiO2的摩尔百分比为0.25%、醇解时间为8 h时,TiO2在紫外光下...  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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