查询词典 TIO

The structural and photocatalytic properties of TiO〓 as well as surface acidity were greatly improved by sulfation. SO〓〓/TiO〓 solid superacid with Hammett constant Ho less than -12.14 was prepared by treating the TiO〓 with 1.0mol. L〓 sulfuric acid solution and then calcining at 450℃ for 3h. When compared to unmodified TiO〓, the SO〓〓/TiO〓 superacid catalyst exhibited higher anatase content, smaller crystal size, higher specific surface area, centralized pore size distribution, and the blue-shifted band edge of uv-vis adsorption spectra. Furthermore, the SO〓〓/TiO〓 superacid also showed excellent reaction activity and stability for CH〓Br photocatalytic decomposition even under the moist reaction conditions. 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。

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。

In the condition of keeping F、 K、Na content fixed, To improve slag structure and raise slag melting point and viscosity, MgO content is raised and TiO〓 is added. the main content is as follows:(1) Keeping CaO/SiO〓 fixed, MgO content rises from 10% to 16%, the free running temperature goes up 106℃, the viscosity goe down at bigger than 1425℃, but difference is little; keeping /SiO〓 fixed, MgO content rises from 10% to 16%, the free running temperature rises 87℃, the viscosity rises too; adding TiO〓 to 5%, the free running temperature goes up 98℃, the viscosity rise a little.(2) Powder crystal x ray diffraction and microscopic analysis shows: increasing MgO content, the cuspidine will decreace or even disappear, the monticellite goes up with MgO content rising, keeping /SiO〓 fixed, Akermanite content goes up, for high melting point minerals appear or go up, the free running temperature of the slag bearing F is raised; Adding TiO〓, high melting point mineral—Perovskite forms, it can making other minerals'crystalling fast, it is the reason that TiO〓 raises the free running temperature of the slag bearing F.

2对测定粘度的冷凝渣所进行的X粉晶衍射及显微分析和鉴定表明，增加MgO含量，渣中枪晶石将减少甚至消失，而钙镁橄榄石则随MgO含量增加而增加，在／SiO〓不变时，黄长石含量也有所增加，高熔点矿物的出现和增加，提高了含氟熔渣的熔化性温度；加入TiO〓熔渣中将形成高熔点矿物-钙钛矿，钙钛矿的形成还促使黄长石的结晶，这是TiO〓提高含氟熔渣熔化性温度的根本原因。

Since H〓S and SO〓 adsorbed on TiO〓 could react with each other and TiO〓 is the medium of their electron transfer, thus SO〓 could not be adsorbed quite strong on the active site of TiO〓, which makes it more resistant to sulfating and increase the stability of catalyst. Finally, the model and mechanism of the reduction of SO〓 by NH〓 to elemental sulfur is advanced as follows: on the sulfide catalyst, ammonia is decomposed to N〓 and H〓, and H〓 reacts with SO〓 to form the intermedium of H〓S; then H〓S and SO〓 react as Claus reaction on TiO〓 catalyst.

反应系统中过量水蒸气的存在使催化剂表面某些活性位被水蒸气抑制使活性和选择性有较大幅度降低，但这种影响是可逆的，不会造成催化剂永久性中毒；另外当单质硫和水蒸气同时存在时，在〓催化剂上能够生成硫化氢和二氧化硫，而且由于硫化氢和二氧化硫化学吸附能力不同而导致它们的脱附顺序不同，硫化氢的生成温度总是低于二氧化硫的生成温度，说明过量水蒸气的存在会导致氧化物催化剂上逆克劳斯反应的发生；而在硫化物催化剂上几乎没有硫化氢和二氧化硫生成，说明硫化物催化剂能够抑制逆克劳斯反应的发生。

The effect of mesh TiO〓/Ti used to treat rhodamine B and rose bengal was equivalent to that of 0.1～0.3％ TiO〓 suspensions, it indicated that the photoelectrocatalytic oxidation system of mesh TiO〓/Ti could replace the system in above concentration condition basically. The content, which is similar to the result of this study, has not been reported in present domestic and oversea researches of fixed TiO〓 catalysts.

用丝网TiO〓／Ti催化剂光电催化降解若丹明B和虎红，其处理效果相当于TiO〓浓度为0.1-0.3％的悬浆体系，表明以丝网TiO〓／Ti为催化剂的光电催化氧化体系基本上可以代替上述浓度条件下的TiO〓悬浆体系使用，在目前国内外固定态TiO〓催化剂研究中，尚无类似报道。

When the is 0.1mol/l, ratio / is 0 or 4, aged at 95250℃ for 24 hours, anatase and rutile TiO〓 particles are formed respectively; when the ratio / is between 0 and 4, mixture of anatase and rutile TiO〓 particles is formed, the high the temperature the more the rutile phase. When the / is 5, aged at below 200℃ for 24 hours, amorphous product is gained, aged at 250℃ for 24 hours, olive-like TiO〓 particles with brookite structure are formed.

Ti〓=0.1mol·L〓时，95～250℃陈化，/比为0时，得到金红石型TiO〓颗粒，/比为4时，得到锐钛型TiO〓颗粒；/比介于0～4，可得到金红石型与锐钛型混合二氧化钛颗粒，温度越高含金红石型成分越多；/比为5，200℃以下陈化，得无定型产物，250℃陈化得橄榄形单分散板钛矿型二氧化钛。

SO〓〓/M〓O〓 solid superacid was applied to the photocatalytic oxidation of organic pollutants for the first time. Porous SO〓〓/TiO〓 solid superacid catalysts with high specific surface area were prepared by sol-gel method. The photocatalytic degradation of bromomethane was used as model reaction. The influence of impregnation with H〓SO〓 solution on the structure of catalysts and their photocatalytic performance was systematically studied by using X-ray diffraction, X-ray photoelectron spectroscopy, N〓 sorption analysis applying BET method, UV-Vis diffuse reflectance spectroscopy, FTIR spectroscopy, O〓-TPD and photocatalytic activity measurement. The acidity of TiO〓-based catalysts was investigated by Hammett indicator method, NH〓-TPD and IR spectra of pyridine adsorbtion. The mechanism of superacidifing effects on photocatalytic performances such as the photocatalytic degradation rate of bromomethane, apparent kinetic constant and apparent quantum efficiency was discussed.The results indicated that SO〓〓 is combined with metal ions of TiO〓 in a chelating bidentate mode.

本文首次将SO〓〓/MxOy型固体超强酸催化剂用于光催化氧化有机污染物研究，采用溶胶-凝胶法制备了具有多孔性和大比表面结构的二氧化钛基固体超强酸光催化剂SO〓〓/TiO〓，以光催化降解溴代甲烷为模型反应，系统地研究了H〓SO〓浸渍处理对催化剂表面酸性及其气相光催化性能的影响，结合XRD、BET、XPS、FTIR、Hammett指示剂法、吡啶吸附红外光谱、NH〓-TPD、O〓-TPD、紫外可见漫反射光谱等多种表征手段，深入地讨论了超强酸化对TiO〓的改性机理，阐明了引起SO〓〓/TiO〓超强酸催化剂光催化降解溴代甲烷的转化率、表观反应速率常数和表观量子效率变化的本质原因。

The technological condition of preparation of mesh TiO〓/Ti catalyst was optimized by means of XRD and SEM with the analysis of effects of dyes photoelectrocatalytic degradation. The diameter of TiO〓/Ti catalyst particle was nanometer level The effects of bias voltage and light intensity on the process of photoelectrocatalytic oxidation, the adsorption property of electrode surface, the extent of mineralization of rhodamine B and rose bengal were investigated using mesh TiO〓/Ti as catalyst of photoelectrocatalytic oxidation system.

利用拉曼光谱和XRD等测定手段并结合染料的光电催化降解效果的分析，优化了丝网TiO〓／Ti催化剂制备的工艺条件，研制出高效丝网纳米级TiO〓／Ti催化剂，并将该催化剂用于光电催化氧化体系，研究了氧化体系中外加偏压、光强等因素对光电催化氧化过程的影响以及催化剂的表面吸附性能、染料若丹明B和虎红在光电催化氧化过程中的矿化程度。

Basanite and tephrite from Mt. Crater, Cape Bird and Bonney Lake exhibit similar composition in major elements and trace elements, rare earth elements . They are enriched in MgO, TiO〓, transitional elements and compatible elements , and depleted in SiO〓, Al〓O〓, Na〓O, K〓O, incompatible elements and rare earth elements; Latite from Cape Rodeys and Cape Evens are different from basanite and tephrite, they are enriched in SiO〓, Al〓O〓, Na〓O, K〓O, incompatible elements and rare earth elements, and depleted in Mgo, TiO〓, transitional elements and compatible elements. Volcanic rocks in five regions have the same isotopic ratio of 〓Sr/〓Sr (0.703115-0.703334) and 〓Nd/〓 Nd (0.512892-0.513076), however,〓Pb/〓Pb ratio in volanic rocks from Mt. Crater, Cape Bird and Bonney Lake is lower than those of Cape Rodeys and Cape Evens.

在主元素氧化物和微量元素、稀土元素含量上，克雷克特山、鸟角和博尼湖南岸的碧玄岩、碱玄岩成分比较类似，均具有较高的MgO、TiO〓、过渡元素和相容元素，较低的SiO〓、Al〓O〓、K〓O、Na〓O、不相容元素和稀土元素；罗德角和伊万思角安粗岩雷同，它们具有较高的SiO〓、Al〓O〓、Na〓O、K〓O、稀土元素和不相容元素，较低的MgO、TiO〓、过渡元素和相容元素，但五地区火山岩几乎具有一致的Sr、Nd同位素比值，〓Sr/〓Sr＝0.703115-0.703344、〓Nd/〓Nd＝0.512892-0.513076，在Pb同位素比值上，五地区的〓Pb/〓Pb＝18.664-19.913，其中碧玄岩和碱玄岩比安粗岩的比值稍低。

These phenomenon showed that there were interactions between the frontier orbits of TiO〓 semiconductor and the heteroatom. It give a further support to the new point of view drown by us that the DOS at the lower part of CB and the upper part of VB of semiconductor nano-TiO〓 was important to the photocatalytic activity.

说明了杂原子的前线轨道能级与TiO〓半导体的前线轨道之间有相互作用，从而进一步印证了我们提出的半导体光催化剂价带顶部和导带底部的能级密度对纳米TiO〓催化剂光催化活性有较大影响的新观点。

The United Kingdom has pledged to provide technical assistance to the peacekeeping effort in Darfur, including airlifting supplies and equipment to assist the African peacekeepers.

英国承诺为达佛的維和努力提供技术帮助，包括提供非洲的維和部队空运补給和裝备。

Results: The level of ET-1mRNA in placental villus was significantly higher in pre-eclamptic women than that in control group.

结果：妊高征组患者胎盘绒毛组织ET-1 mRNA的表达较正常妊娠组明显增高。