纳米级二氧化锆的制备技术和表征手段

纳米二氧化锆是一种新型的高科技材料，有着广泛而重要的用途。本文根据国内外研制制备的最新进展及其发展趋势，综述了纳米级二氧化锆的制备技术及表征方法。     

二氧化锆制备技术进展及发展趋势

本文在介绍锆英石分解制二氧化锆的工业生产方法及进展后，认为生产作为结构材料使用的二氧化锆之传统工艺，应设法降低成本，其中等离子体法和电熔法最具发展潜力；同时指出，为适应功能材料的发展需要，应加快开发制备高纯、超细、稳定二氧化锆的工艺方法。     

二氧化锆制备及其应用

二氧化锆是一种高熔点晶体,具有许多优良特性。本文就二氧化锆的制备方法进行了论述,并对二氧化锆的应用进行了讨论     

纳米级二氧化锆的表征和应用

纳米二氧化锆是一种新型的高科技材料，有着广泛而重要的用途。本文根据国内外研究制备的最新进展及其发展趋势，综述了纳米级二氧化锆表征方法和近年来新的应用领域和研究前沿。     

二氧化锆制备及其应用

二氧化锆是一种高熔点晶体,具有许多优良特性,本文就二氧化锆的制备方法进行了论述,并对二氧化锆的应用了讨论。     

纳米二氧化锆制备技术及应用研究

纳米二氧化锆具有耐高温、耐腐蚀、相变增韧、化学稳定性好等众多优良的物理和化学特性,目前已被广泛应用于耐高温功能性陶瓷、工业催化、润滑、传感器等领域。制备出高纯高性能的纳米二氧化锆粉体是近年来纳米粉体制备技术的热门领域之一,本文总结了纳米二氧化锆的制备方法及其优缺点。最后对纳米二氧化锆的应用进行了介绍。     

二氧化锆的相稳定及其制备方法

简要地介绍了二氧化锆常见的物理、化学性质及其推广应用受到限制的主要原因.综述了目前国内外二氧化锆相稳定的主要方法--物理稳定方法和化学掺杂稳定方法的机理及研究现状.简单介绍了稳定二氧化锆的分类,同时对国内外稳定二氧化锆的制备方法及工艺进展进行了系统的叙述,并对各种制备方法进行了分析讨论,并作了简要的评述,进而提出了对今后研究方向的展望.     

氯氧化锆前驱体制备纳米氧化锆的机理探讨

介绍了以无机盐氯氧化锆为前驱体，以氢氧化铵为水解促进剂，通过溶胶-凝胶法制备纳米二氧化锆的工艺条件。结合XRD和TG—DSC等测试手段，研究了溶胶-凝胶法制备纳米二氧化锆的机理。结果表明，锆原子在胶体中是以氢氧化锆四聚物的形式存在的，纳米氧化锆是四聚物脱去质子进一步缩聚的结果。     

纳米级二氧化锆的制备和应用

纳米二氧化锆是一种新型的高科技材料,有着广泛而重要的用途。根据国内外研究制备的最新进展及其发展趋势,综述了纳米级二氧化锆的制备技术和近年来新的应用领域和研究前沿。     

钴-硼/二氧化锆催化剂催化硼氢化钠水解制氢研究

采用浸渍负载-还原法制备了钴-硼/二氧化锆催化剂,研究了催化剂在催化硼氢化钠水解制氢中的性能。研究了催化剂的制备条件（钴与二氧化锆物质的量比、钴与硼氢化钠物质的量比）对其催化性能的影响,并考察了催化剂用量、反应温度、搅拌转速对硼氢化钠水解制氢的影响。结果表明,在钴与二氧化锆物质的量比为0.16:1、钴与硼氢化钠物质的量比为1:5条件下制备的钴-硼/二氧化锆催化剂催化硼氢化钠水解制氢的速率最快。硼氢化钠水解制氢速率随催化剂用量的增加和反应温度的升高而增大,随搅拌转速的增加呈现先增大后减小的趋势。反应动力学计算出钴-硼/二氧化锆催化剂催化硼氢化钠水解对硼氢化钠的浓度属于零级反应。钴-硼/二氧化锆催化剂的硼氢化钠水解反应活化能为43.97 kJ/mol。     

高锆稳定型碳酸锆铵抗水剂的研究

新型抗水剂碳酸锆铵由于具有适用性广、熟化快、抗水性强等突出优点,受到广大造纸厂家的青睐,但国内生产的碳酸锆铵成品中二氧化锆含量较低,而且稳定性较差.本研究以提高碳酸锆铵成品中二氧化锆的含量为目标优化合成工艺,同时通过选用理想的稳定剂增加其稳定性.制得的产品中二氧化锆的含量达到20%～22%,且具有较高的稳定性.     

Hardening in Creep of Alumina by Zirconium Segregation at the Grain Boundary

The effect of zirconium segregation on hardening in the creep of fine-grained alumina was studied by using the tensile creep test. To avoid the effect of zirconia particle dispersion on creep, 100-ppm-zirconium-doped alumina and 1000-ppm-zirconium-doped alumina were fabricated by using a zirconium-containing precursor. The scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy study revealed that the zirconium was segregated at the alumina grain boundary. Doping even as little as 100 ppm of zirconium caused the hardening effect. The creep rate was further reduced by increasing the amount of zirconium dopant. Although the stress exponent of 2 was not affected by zirconium segregation, the apparent activation energy of the creep was found to be increased, from 520 kJ/mol for undoped alumina to 670 kJ/mol for 100-ppm-zirconium-doped alumina and 760 kJ/mol for 1000-ppm-zirconium-doped alumina. It was suggested that grain-boundary sliding was accommodated by impurity-drag-controlled diffusional creep.     

Preparation and characterization of ZrO2/Ti electrode for waste water purification system

We have investigated the effects of the etching method of a Ti substrate for a metal oxide electrode on the electrochemical characteristics of the electrode. The preparation method and electrochemical characterization of zirconium oxide films on etched Ti substrate has been also studied. The HCl etching was developed a fine and homogeneous roughness on the Ti substrate. Fabrication and material properties of the metal oxide electrode, which is known to be so effective to generate ozone and sodium hypochlorite (NaOCl) as power oxidant, were studied. A proper metal oxide material focus zirconium oxide through reference paper. A coating method to enhance the fabrication reproducibility of the zirconium oxide electrode was used dip-coating method by zirconium oxychloride. Zirconium oxide films on the Ti substrate were analyzed by SEM, XPS and cyclic voltammetry.     

高纯氯氧化锆和二氧化锆的制备

研究了工业氯氧化锆重结晶制备高纯氯氧化锆的过程，通过选择，确定氯氧化锆溶液浓度为160g/L，结晶酸度为5.5-6.0mol/L，煅烧过程中盛装高纯氯氧化锆匣钵为石英匣钵，从而得到产品纯度为99．9％的高纯二氧化锆。     

茂金属催化剂的合成与表征研究

研究了以甲基锂、2,3-二苯基环戊烯酮、氯化锆为原料合成了主催化剂二(1,2-二苯基-3-甲基环戊二烯基)二氯化锆,并对其进行负载和表征研究。结果表明,得到的产物基本符合要求,产品的纯度较高,具有良好的应用前景。     

Decomposition of 2-chlorophenol by supercritical water oxidation with zirconium corrosion

The 2-chlorophenol (2-CP) was oxidized in a continuous anti-corrosive supercritical water system. The variation of decomposition efficiency by the corrosion of zirconium 702 was also studied at the variation of feed concentration and reaction time. According to AES depth profile, the oxygen penetration depth to zirconium was not proportional to the exposure time. It might stem from the formation of zirconium oxide layer on the surface delaying the corrosion. However, the increase in feed concentration accelerated the corrosion of zirconium. The corrosion of zirconium at low feed concentration led to the improvement of decomposition efficiency due to the catalytic effect of formed zirconium oxides, while that at high feed concentration deteriorated the decomposition efficiency owing to large consumption of oxidant in corrosion.     

Physicochemical Transformations During Low-Temperature Synthesis of Zirconium Carbide

Refractories and Industrial Ceramics - Joint reduction of zirconium dioxide and sodium carbonate to form zirconium carbide was studied. Magnesiothermic reduction of ZrO2 was shown to occur at 600...     

THE DETERMINATION BY X-RAY METHODS OF CRYSTALLINE COMPOUNDS CAUSING OPACITY IN ENAMELS*

The crystatline compounds present in vitreous enamels were determined by X-ray methods, particular reference being given to the opacifiers. It was shown that tin is present in enamels as crystalline tin oxide and antimony as the crystalline antimony pentoxide. Fluorspar added to the enamel contributes crystalline calcium fluoride. Cryolite and sodium silicofluoride contribute crystalline sodium fluoride. Other opacifiers and compounds such as zirconium oxide, zirconium silicate, calcium phosphate, arsenic oxide, and zinc sulfide added to enamels were studied. With the exception of the zirconium opacity the compounds causing opacity in enamels were identified alone and in the presence of other opacifiers.     

氢氧化锆非等温热分解动力学研究

利用TG-DTG-DSC技术研究了氢氧化锆非等温热分解过程,应用模型法和非模型法对热分解过程进行了动力学分析,建立了动力学函数,得到了氢氧化锆热分解反应机理。氢氧化锆在氮气中热分解的活化能E=71.26 kJ/mol,指前因子lgA=18.20,机理函数积分式g(α)=[-ln(1-α)]4,微分式f(α)=(1-α)[-ln(1-α)]-3/4,反应机理为随机成核和随后生长。     

Lead Zirconate Titanate Prepared from Different Zirconium and Titanium Precursors by Sol-Gel

Modified sol-gel processes have been developed for the preparation of lead zirconate titanate (PZT) (52/48) powders. These processes use different starting sources to introduce the titanium and zirconium components, namely tetraethyl orthotitanate, titanium isopropoxide, or titanium diisopropoxide bis(2,4-pentanedionate) for titanium and zirconium propoxide or zirconium acetylacetonate for zirconium. To achieve stable and homogeneous precursor systems, several solvents (acetic acid, 1,2-propanediol, propanol, and distilled water) and chemical modifying additives, such as acetylacetone and nitric acid, were also introduced for the preparation processes. The influence of the different precursors on the crystallization behavior of the sol-gel-derived powders was studied. Well-crystallized single-phase PZT powders were obtained after heat treatment at 600°C for 1 h. The powders obtained sintered well at 1000°C/2 h and a homogeneous microstructure with small grain sizes was obtained.