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The invention discloses a method for preparing novel nanometer TiO2 optical catalyst material, comprising that (1) preparing gel solution of modified lanthanide series that mixing butyl titanate, alcohol solvent, azotic acid, polyvinyl alcohol and lanthanide element,(2) using alkali liquid to treat the quartz fiber leaked from side wall,(3) using drawing membrane and high-temperature sintering to form modified TiO2 optical catalyst material on the surface of quartz fiber.

本发明公开了一种制备新型纳米TiO2光催化材料的方法，包括(1)配置镧系元素改性的溶胶溶液：将钛酸四丁酯、醇类溶剂、硝酸、聚乙烯醇和镧系元素的盐类混合搅拌；(2)利用碱液对侧壁漏光石英光纤进行处理；(3)通过提拉成膜和高温煅烧，在石英光纤表面形成改性TiO2光催化材料。

For low molar ratios of Al/Zr, a hypsochromic shift of the initial catalyst absorption band, corresponding to the monomethylation of the catalyst, was observed. Further addition of AlEt2Cl was accompanied by a continuous bathochromic shift of the maximal wavelength corresponding to the formation of more dissociated ionic active species. Then, there would be a coordination of monomer to the ionic active species.

结果表明，无论是AlEt_2Cl还是MAO，少量的助催化剂首先使催化剂发生单烷基化反应，主催化剂金属中心的最大吸收峰波长发生蓝移，而当助催化剂量进一步增加时，金属中心的最大吸收峰波长红移，单烷基取代的催化剂被大量的助催化剂夺去电子成为缺电子的阳离子活性中心，以便烯烃单体的配位插入。

Using levulinic acid and phenol as raw materials, hydrochloric acid as catalyst and thioglycolic acid as assistant catalyst, the synthesis technology of diphenolic acid, a new polymer material substitution for biphenol A, was investigated.

研究了以苯酚和新型平台化合物乙酰丙酸为原料，采用盐酸为催化剂、巯基乙酸为助催化剂催化合成高分子材料单体双酚酸的合成工艺。

After pretreating of carrier by vapour the catalytic performance of this catalyst was improved.The products have better viscosity and lower bromic bond when the new catalyst has been used.The products are good base oil for producing high quality lubricating oil.

同时载体经水蒸气预处理，酸性有所变化，催化剂的各项性能均有显著的提高，产品具有较好的粘度和较低的溴价。

The apparent quantum efficiency of SO〓〓/TiO〓 was 10 times of that of TiO〓 catalyst for the photocatalytic degradation of bromomethane. Therefore, the SO〓〓/TiO〓 superacid catalyst is promising for practical application in environmental remediation.It was found that both L and B acid sites exist on SO〓〓/TiO〓 photocatalyst while only L acid sites on TiO〓 photocatalyst. On the basis of experimental results, the synergistic model of superacidic centers was proposed for SO〓〓/TiO〓 photocatalyst to explain the photocatalytic behavior and the mechanism of superacidifing effects, assuming that the adjacent L and B acid sites induced by SO〓〓 comprise cooperatively the superacidic center on superacid photocatalyst. The group cooperation of the superacidic center could strengthen the surface acidity, increase surface acid sites and the adsorbtion of O〓, promote separation of photogenerated electron-hole pair, enhance the interfacial transfer of charges and reversibility of water adsorption. Consequently the excellent photocatalytic activity, reaction stability and resistibility to humidity of SO〓〓/TiO〓 superacid photocatalyst may attributed to the group cooperated effect of the superacidic center on the photocatalyst.

研究结果表明：SO〓〓与TiO〓表面的结合为螯合式双配位结构；TiO〓光催化剂表面经H〓SO〓浸渍处理后，提高了表面酸性，改善了催化剂结构和光催化性能，当H〓SO〓浸渍浓度为1.0mol.L〓、烧结温度为450℃时，可制得SO〓〓/TiO〓超强酸催化剂(H〓＜-12.14)，其结构和光催化活性得到明显改善，与TiO〓相比，SO〓〓/TiO〓光催化剂的锐钛矿含量高、晶粒小、BET比表面积大、孔径分布集中、光谱吸收边蓝移，具有优异的光催化氧化活性、稳定性及抗湿性能，光催化降解溴代甲烷的表观量子效率比TiO〓催化剂提高了一个数量级，是一种有实际应用前景的高效光催化剂；由此提出了SO〓〓/TiO〓超强酸催化剂表面集团协同作用的超强酸中心模型，认为在SO〓〓/TiO〓超强酸催化剂表面，由SO〓〓诱导的相邻L酸中心和B酸中心组成了集团协同作用的超强酸中心，其集团协同作用显著地增强了催化剂表面酸性、增大了表面酸量及O〓吸附量、促进了光生电子和空穴的分离及界面电荷转移，具有可逆吸附水的性能，是SO〓〓/TiO〓超强酸催化剂具有优异的光催化氧化活性、很好的活性稳定性及抗湿性能的重要原因。

Stannous caprylate was selected as the catalyst. Under certain vacuum, we investigate the relation of both the dose of catalyst, the temperature of reaction, the time of reaction and the molecular weight of the PLA.Furthermore we investigate how the purity of lactide and the circumstance of vacuum affect the molecular weight of the PLA.

实验中选用辛酸亚锡Sn(oct_2为催化剂，在一定的真空度下考察了催化剂用量、反应温度、反应时间与聚乳酸分子量的关系；并考察了丙交酯纯度及真空度对聚乳酸分子量的影响。

The effect of zeolites ion-exchanged by transition metals on thermal catalytic cracking reaction is studied. The product distributions of the cracking reactions catalyzed by theβor ZSM-5 zeolites exchanged with transition metals are different from that catalyzed by corresponding Hzeolites, which means the mechanism of cracking reactions has varied. Group Ⅷ metals Fe, Co, Ni and Cu, Zn are shown to be of strong catalytic activity of oxidative dehydrogenation, while Ti and Cr are not of oxidative activity. Catalyzed by zeolites or catalyst containing Ag, conversion of thermal catalytic cracking reactions and the yield of ethylene increase while the yield of propylene does not decrease. Silver can not only promote the formation of carbonium ion, but also convert carbonium ion into free-radical via redox reaction. The weak adsorption of olefins on silver reduces the occurrence of hydrogen transfer and dehydrogenation. As a result, the yield of light olefins is favored by silver in the catalyst.

采用过渡金属交换的分子筛作为催化剂，进行催化热裂解制取乙烯的反应，研究发现，在β沸石分子筛和ZSM-5分子筛中引入过渡金属后，催化热裂解反应的产物分布与相应的氢型分子筛相比有了较大的变化，说明过渡金属的加入对于催化热裂解反应的机理具有影响，Ⅷ族金属如Fe、Co、Ni和第Ⅰ、Ⅱ副族Cu、Zn表现出较强的氧化脱氢活性，产物中氢气、焦炭的产率很高，Ti、Cr则未表现出氧化作用：分子筛及催化剂中引入银后，催化热裂解反应的转化率和乙烯的产率有了提高，丙烯产率没有很大的变化，说明银在催化热裂解反应中能够促进正碳离子的生成，又有可能通过氧化-还原作用部分改变反应机理，促进了自由基的生成，并且由于银对烯烃的吸附很弱，其氢转移反应和脱氢、加氢活性比较低，有利于烯烃产率的提高。

The influence of reaction condition on the yield of isopropyl chloroacetate as investigated such as catalyst loading, molar ratio of chloracetic acid to isopropanol, reaction time and repeated use of the catalyst.

考察了催化剂的用量、反应物物质的量比、反应时间和催化剂的重复使用等因素对收率的影响。

In this paper, the applications of the environmental friendly solid acid catalysts for esterification were studied and the activities of these catalysts were discussed, by which the solid acid ferric sulfate x-hydrate was used first as catalyst in the synthesis of dimethyl fumarate and ethyl chloroacetate and solid super acid SO42-/Fe2O3 was used first as catalyst in the synthesis of ethyl p-nitrobenzoate.

本文研究了对环境友好的固体酸催化剂在酯化反应中的应用，首次以固体酸Fe_2(SO_4)_3·xH_2O为催化剂合成了新型防霉剂富马酸二甲酯和化工原料氯乙酸乙酯，以固体超强酸5O_4~(2-)／Fe_2O_3为催化剂合成了医药中间体对硝基苯甲酸乙酯，并探讨了这些催化剂的催化活性。

A mathematical model is established, which considers multicomponent diffusion, chemical reaction, pore size distribution of the catalyst and capillary condensation of condensable components within the catalyst pellet.

将多组分扩散、化学反应、催化剂孔径分布以及反应组分在催化剂内部的毛细冷凝等因素结合在一起，建立了描述催化剂处于内部部分润湿状态下的反应动力学的数学模型。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。