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A novel metallo-organic chemical vapor deposition (MOCVD) technique has been applied to the preparation of the photocatalytic titanium dioxide supported on activated carbon. The effects of various condition parameters such as carrier gas flow rate, source temperature and deposition temperature on the deposition rate were investigated. The maximum deposition rate of 8.2 mg/(g.h) was obtained under conditions of carrier gas flow rate of 400 ml/min, source temperature of 423 K and deposition temperature of 913 K. The deposition rate followed Arrhenius behavior at temperature of 753 K to 913 K, corresponding to activation energy Ea of 51.09 kJ/mol. TiO2 existed only in anatase phase when the deposition temperature was 773 K to 973 K. With increase of deposition temperature from 1073 K to 1273 K, the rutile content sharply increased from 7% to 70%. It was found that a deposition temperature of 773 K and a higher source temperature of 448 K resulted in finely dispersed TiO2 particles, which were mainly in the range of 10-20 nm. 相似文献
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New cellulosic titanium dioxide nanocomposite as a protective coating for preserving paper-art-works
We investigate the TiO2 role in the inherent protection of paper works of art to protect them against damaging effect of ultraviolet radiation, pollutant gasses, mold and bacteria. In this study a cellulosic nanocomposite of TiO2 were used as protective coating on the surface of paper fibers. This layered nanocomposite can act as a consolidate materials too. Furthermore, to determine how well paper works screen objects from the damaging effects, two accelerated aging mechanisms due to light and heat are discussed. Results show good stability of papers with nanocomposite coating. Also, a good light stability was shown in the colored paper that treated with this nanocomposite. Furthermore, to demonstrate the degree of antifungal properties of coated papers, papers were treated with two common molds and the good preventive effect of coated paper against molds is described. 相似文献
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该文利用循环伏安法(CV)和线性扫描溶出伏安法(LSSV)研究了对苯二酚(HQ)和间苯二酚(RS)在聚噻吩/纳米二氧化钛修饰玻碳电极(PTh/NTiO2/GCE)上的电化学行为。该修饰电极作为两种苯二酚传感器表现出极好的灵敏度和选择性。在0.2mol/L柠檬酸-磷酸氢二钠缓冲溶液(pH 4.6),RS和HQ的氧化峰电位相距508 mV,且在PTh/NTiO2/GCE上的峰比在裸GCE上的高出6.5倍。在最佳条件下,PTh/NTiO2/GCE对HQ和RS在1.0×10-7～8.0×10-6范围内都有较好的线性关系,混合物中的检出限(S/N=3)分别为3.3×10-8 mol/L和3.7×10-8 mol/L。通过计算得出了一些动力学参数如电子转移数(n),质子转移数(m)。该法被用来同时测定废水中的RS和HQ结果满意。 相似文献
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本文首次研究了以β二酮及酯作为配体的六种过渡金属配合物的热稳定性,并用DTA-TG和TG-DTG技术研究了配合物的热分解机理,根据分解热估算出配合物的断裂键能。 相似文献
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It is difficult to directly dope europium complexes in gel because the excessive water or high acidic condition may lead to their decomposition. We prepared a novel homogeneous TiO2 gel containing Eu-phen complexes by using an in-situ synthesis method. The formation of Eu-phen complexes in sol-gel derived TiO2 was confirmed by luminescence excitation spectra. The effects of temperature and aging time on in-situ synthesis are discussed. The luminescence spectra of gel containing europium complexes were also compared with the pure Eu-phen complexes. 相似文献
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INTRODUCTION Monocrystalline SBN (Strontium barium nio-bium, SrxBa1?xNb2O6, denoted SBNx?100, where 0.25≤x≤0.75) solid solution, is currently being inves-tigated as potential material for many micro-device applications, such as piezoelectric infrared detectors, piezoelectric, electro-optic modulators, and holo-graphic storage (Koch et al., 1998), because SBN has one of the largest known linear electro-optic coeffi-cients (r33=1300 pm/V for SBN75), two orders of magnitude larger th… 相似文献
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本文采用激光熔覆技术,探讨制备ZrO_2/Ti梯度功能材料,利用SEM和EPMA分析激光熔覆层,过渡层、热影响区的组织形貌和各组元的成份分布。用X射线衍射和微区X射线衍射技术分析激光熔覆区的氧化锆相变及各区域的相组成。得到:经过激光熔覆处理,熔覆区氧化锆由C—ZrO_2和T—ZrO_2组成,激光熔覆层、过渡区,热影响区的组织分别为ZrO_2枝晶 Ti_2O、粒状Z_rO_2 α相、片状α组成,在过渡区内成份是渐变的,组织为陶瓷相ZrO_2和塑性相α相混合。此工艺是制备ZrO_2/Ti梯度功能材料有前途的方法。 相似文献
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钛白废水综合治理工艺作为一个系统工程构思,在明确钛白废水产生原因及主要污染因子后,首先提出钛白废水一次石粉中和,经压滤得到白石膏和FeSO4溶液,然后按FeSO4溶液浓度的高、低分别处理:高浓度FeSO4溶液用于制备铁红晶种;低浓度FeSO4溶液则进行二次石灰乳中和,经压滤得到红石膏和回收水。该方案不仅能较好地治理钛白废水,得到高价值副产品,而且治理成本低,使用设备简单。 相似文献
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该文通过对攀西钒钛资源开发利用现状以及存在的主要问题的调查和研究,分析了生态环境和技术战略选择对可持续开发利用的影响,论述了生态环境与技术战略选择之间的关系,指出在攀西钒钛资源的开发利用中,必须在生态环境的约束条件下选择和实施技术战略。该文采用优势－弱点－机会－威胁矩阵（SWOT）分析方法对攀西钒钛资源开发利用的关键影响因素进行了分析研究,提出了技术战略的备选方案－ST方案;最后,运用定量战略计划矩阵（QSPM）从备选方案中选择出了在攀西生态脆弱约束条件下的钒钛资源开发利用的技术战略,即引进与自主攻关相结合,走“引进—消化吸收—创新—提高”的道路,攻克对攀西生态环境影响大的钒钛资源开发利用关键技术。 相似文献