可见光敏感型纳米氮氧化钛光催化剂的制备和表征

利用高温气固相反应合成制备纳米氮氧化钛.研究制备过程中反应温度和反应时间对样品粒径和晶型的影响.采用X射线衍射、透射电子显微镜、X射线光电子能谱和紫外可见光谱等手段对样品形态结构进行表征.结果表明,纳米氮氧化钛粒径为10～30nm,平均晶粒尺寸为16nm,颗粒晶型为锐钛矿型,并且发现氮氧化钛对波长在400～500nm的可见光有明显吸收.

氮氧化钛支架在急性ST段抬高型心肌梗死介入治疗中的应用

目的探讨氮氧化钛支架在急性ST段抬高型心肌梗死（STEMI）患者经皮冠状动脉介入治疗（PCI）中的疗效及安全性。方法 46例确诊为STEMI患者置入氮氧化钛支架,观察术后30 d及6个月主要心脏事件（心脏性死亡、非致死性心肌梗死、心绞痛）的发生率。结果共置入58枚氮氧化钛支架,狭窄直径减少至0~8%,梗塞相关血管再通后前向血流均达TIMI 3级。术后1例在30 d内因恶性心律失常死亡,6个月内有3例患者出现心绞痛,1例患者出现再发心肌梗死。结论氮氧化钛支架在STEMI患者中应用具有较高的安全性及有效性。

氮氧化钛生物有效性支架与雷帕霉素药物洗脱支架临床应用比较

目的：对比研究氮氧化钛生物有效性支架（Titan2-BAS）与雷帕霉素药物洗脱支架（sirolimus-eluting stent,SES）在冠状动脉血运重建方面的临床疗效.方法：141例冠心病患者,根据植入的支架不同分为A组（Titan2-BAS）87例,B组（SES）54例,均采用经桡动脉或尺动脉途径冠脉血运重建.A组阿司匹林与氯吡格雷治疗1~3 mo,B组至少12 mo.计算A,B两组支架病变的通过率、早期支架内血栓发生率及随访MACE发生率（指死亡、急性心肌梗死、靶血管重建等）.结果：①A组病变内径（3.1±0.4）mm,长度为（24±3）mm,B组病变内径（3.0±0.5）mm,长度为（22±4）mm,两组无显著差异（P〉0.05）.②A组146处〉75%狭窄病变共植入Ti-tan2-BAS 168枚,1枚支架未能通过病变（RCA）,通过率99.3%;B组86处病变共植入SES94枚,通过率100%,两组无显著差异（P〉0.05）.③随访1~17 mo,平均5.8 mo.两组均无死亡病例;A组无急、晚期血栓.B组1例术后2 d出现支架内血栓;A组1例术后3 mo行靶血管重建,B组无靶血管重建;两组MACE发生率无显著差异（P〉0.05）.结论：在本研究样品量情况下,Titan2-BAS与SES在冠脉血运重建方面的近期及远期疗效相近,Titan2不增加MACE发生率.

经桡/尺动脉途径置入氮氧化钛涂层支架治疗老年冠心病

目的探讨氮氧化钛涂层支架(TITAN2)在老年经桡/尺动脉途径行冠状动脉血运重建方面的临床治疗效果。方法共入选29例冠心病患者,男16例,女13例。均采用经桡动脉或尺动脉途径行冠脉血运重建。计算TITAN2支架病变的通过率、早期支架内血栓发生率及随访主要不良心脏事件(死亡、急性心肌梗死、再次血运重建)发生率。结果29例冠状动脉造影发现43处>75%狭窄病变,植入支架42枚,1枚支架未能通过病变(右冠状动脉),通过率97.7%。植入支架后无残余狭窄、支架脱载、内膜撕裂、支架内早期血栓形成及冠脉破裂。随访1～5个月,无主要心脏不良事件发生。结论TITAN2支架在老年冠脉血运重建方面临床应用效果良好。

新型氮氧化钛生物有效支架与国产雷帕霉素药物洗脱支架在老年冠状动脉血运重建临床应用的对比研究

目的对比研究氮氧化钛生物有效性支架(Titan2-BAS)与国产雷帕霉素药物洗脱支架(SES)在老年冠状动脉血运重建临床应用中的疗效。方法共入选125例老年冠心病患者,男75例,女50例。根据植入的支架不同分为A组(Titan2-BAS)79例,B组(SES)46例,均采用经桡动脉或尺动脉途径冠脉血运重建。A组阿司匹林与氯吡格雷治疗1～3个月,B组至少12个月。计算A、B两组支架病变的通过率、早期支架内血栓发生率及随访主要不良心脏事件(MACE,指死亡、急性心肌梗死、靶血管重建等)发生率。结果(1)A组病变内径(3.1±0.3)mm,长度为(25±3.6)mm,B组病变内径(3.1±0.4)mm,长度为(24±4.2)mm,两组无显著差异。(2)A组129处>75%狭窄病变共植入Titan2-BAS146枚,1枚支架未能通过病变(右冠状动脉),通过率99.3%;B组72处病变共植入SES82枚,通过率100%,两组无显著差异。(3)随访1～17个月,平均5.3个月。两组均无死亡病例;A组无急、晚期血栓。B组1例术后2d出现支架内血栓;A组1例术后3个月行靶血管重建,B组无靶血管重建;综合以上,两组MACE发生率无显著差异(1.3%对2.2%)。结论Titan2-BAS与SES在老年冠状动脉血运重建方面的近期及远期疗效相近,Titan2-BAS不增加MACE发生率。

新型冠状动脉支架——氮氧化钛生物有效性支架

随着医学科学的进步,冠心病的介入治疗越来越普及,各种冠状动脉支架如雨后春笋般涌现。本文综述了一种新型的冠状动脉支架——氮氧化钛生物有效性支架,对其结构特点、临床应用等进行了介绍。

氮氧化钛生物有效性支架与雷帕霉素药物洗脱支架临床应用的比较

目的：对比氮氧化钛生物有效性支架（Titan2-BAS）与雷帕霉素药物洗脱支架（sirolimus—eluting stent，SES）在冠状动脉血运重建方面的临床疗效。方法：冠心病患者141例，根据植入的支架不同分为A组（Titan2-BAS）87例，B组（SES）54例，A组病变内径（3．1±0．4）mm，长度（24±3）mm，B组病变内径（3．0±0．5）mm，长度（22±4）mm，两组无显著差异。均采用经桡动脉或尺动脉途径冠脉血运重建。A组阿司匹林与氯吡格雷治疗1～3月，B组至少12月。计算A，B两组支架病变的通过率、早期支架内血栓发生率及随访MACE发生率（指死亡、急性心肌梗死、靶血管重建等）。结果：A组146处〉75％狭窄病变共植入Titan2-BAS168枚，1枚支架未能通过病变（RCA），通过率99．3％；B组86处病变共植入SES94枚，通过率100％，两组无显著差异。随访1～17（平均5．8）月。两组均无死亡病例；A组无急、晚期血栓。B组1例术后2d出现支架内血栓；A组1例术后3月行靶血管重建，8组无靶血管重建；两组MACE发生率无显著差异。结论：Titan2-BAS与SES在冠脉血运重建方面的近期及远期疗效相近，Titan2不增加MACE发生率。

氮氧化钛涂层支架在冠状动脉血运重建中的初步应用

目的探讨氮氧化钛涂层（TITAN2）支架在经彬尺动脉途径行冠状动脉血运重建的临床效果。方法入选31例冠心病患者，均采用经桡动脉或尺动脉途径行冠状动脉血运重建。计算TITAN2支架病变的通过率、早期支架内血栓发生率及随访MACE发生率。结果31例冠状动脉造影发现46处〉75％狭窄病变，植入支架45枚，1枚支架未能通过病变，通过率97．8％。植入支架后无残余狭窄、支架脱载、内膜撕裂、支架内早期血栓形成及冠状动脉破裂。随访1～5个月，无MACE发生。结论TITAN2支架在冠状动脉血运重建方面临床应用效果良好。

室内装饰品负载氮掺杂氧化钛的光催化性能

采用钛醇盐水解法与溶胶凝胶法,以氨水、尿素、三乙胺为氮源,制备了纳米TiO2-xNx光催化剂。为了在净化室内空气的同时能够装饰环境,提出了喷涂和浸泡2种工艺将光催化剂负载于室内装饰品,并在模拟太阳光的照射下对室内污染物甲醛进行降解。XRD、UV-Vis光谱及XPS分析结果表明,在烧结温度为400℃时得到的3种TiO2-xNx是锐钛矿相,其中以尿素为氮源的TiO2-xNx温度达到600℃时开始发生相转变,3种TiO2-xNx在可见光区域的400～550 nm均出现新的吸收;以氨水、尿素和三乙胺为氮源制备的TiO2-xNx的掺氮量分别为2.77%、0.29%和0.47%。以氨水为氮源制备的光催化剂,14 h降解甲醛的效率达到了95%;以三乙胺为氮源制备的光催化剂7 h降解甲醛的效率达到了96%。因此,应用喷涂法在室内装饰品上负载光催化剂降解室内污染物具有很好的应用前景。

Experimental studies on photocatalytic oxidation of nitric oxides using titanium dioxide

In order to remove nitric oxides （NO） from flue gas, experimental studies on the photocatalytic oxidation （PCO） of NO are carried out in an efficient laboratory-scale reactor. Nano-sized TiO2 particles loading on quartz sand are prepared and used as the photocatalyst. Effects of several key operating parameters on NO conversion are investigated, including operating temperature, NO inlet concentration, oxygen percentage, relative humidity and residence time. The results illustrate that the NO inlet concentration, the oxygen percentage and the relative humidity play an important role in the oxidation of NO. A lower NO inlet concentration and a higher oxygen percentage result in a higher NO conversion efficiency. When the relative humidity is 8%, the maximum value of NO conversion efficiency is achieved. In addition, the operating temperature and the residence time have a little effect on the conversion efficiency of NO.

Synthesis and Characterization of Novel N-doped TiO2 Photocatalyst with Visible Light Active

A novel N-doped TiO2 （N1-N2-TiO2） with substitutional and interstitial N impurities simultaneously was successfully synthesized. The catalyst was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy, photoluminescence, and electron paramagnetic resonance. The results demonstrated that the nitrogen was substituted for the lattice oxygen atoms, and was also interstitially doped into the TiO2 lattice. The photocatalytic tests indicated that the N1-N2-TiO2 showed the highest photocatalytic activities of all the N-doped TiO2 under visible light, attributing to the synergetic effect of substitutional and interstitial nitrogen of N-doped TiO2.

Catalytic oxidation of diesel soot particulates over Ag/LaCoO_3 perovskite oxides in air and NO_x

Ag/LaCoO3 perovskite catalysts for soot combustion were prepared by the impregnation method.The structure and physicochemical properties of the catalysts were characterized using X-ray diffraction,N2 adsorption-desorption,H2 temperature-programmed reduction,soot temperatureprogrammed reduction,and X-ray photoelectron spectroscopy.The catalytic activity of the catalysts for soot oxidation was tested by temperature-programmed oxidation in air and in a NOx atmosphere.Metallic Ag particles were the main Ag species.Part of the Ag migrated from the surface to the lattice of the LaCoO3 perovskite,to form La（1-x）AgxCoO3.This increased the amount of oxygen vacancies in the perovskite structure during thermal treatment.Compared with unmodified LaCoO3,the maximum soot oxidation rate temperature（Tp） decreased by 50-70 ℃ in air when LaCoO3 was partially modified by Ag,depending on the thermal treatment temperature.The Tp of the Ag/LaCoO3catalyst calcined at 400℃ in a NOx atmosphere decreased to about 140℃,compared with that of LaCoO3.Ag particles and oxygen vacancies in the catalysts contributed to their high catalytic activity for soot oxidation.The stable catalytic activity of the Ag/LaCoO3 catalyst calcined at 700℃ in a NOx atmosphere was related to its stable structure.

Resistance to SO_2 poisoning of V_2O_5/TiO_2-PILC catalyst for the selective catalytic reduction of NO by NH_3

A titania pillared interlayered clay（Ti-PILC） supported vanadia catalyst（V2O5/TiO2-PILC） was prepared by wet impregnation for the selective catalytic reduction（SCR） of NO with ammonia. Compared to the traditional V2O5/TiO2 and V2O5-MoO3/TiO2 catalysts, the V2O5/TiO2-PILC catalyst exhibited a higher activity and better SO2 and H2O resistance in the NH3-SCR reaction. Characterization using TPD, in situ DRIFT and XPS showed that surface sulfate and/or sulfite species and ionic SO4^（2-）species were formed on the catalyst in the presence of SO2. The ionic SO4^（2-） species on the catalyst surface was one reason for deactivation of the catalyst in SCR. The formation of the ionic SO4^（2-） species was correlated with the amount of surface adsorbed oxygen species. Less adsorbed oxygen species gave less ionic SO4^（2-） species on the catalyst.

Nitrogen-doped TiO_2 microsheets with enhanced visible light photocatalytic activity for CO_2 reduction

Nitrogen-doped anatase TiO 2 microsheets with 65%（001） and 35%（101） exposed faces were fabricated by the hydrothermal method using TiN as precursor in the presence of HF and HCl. The samples were characterized by scanning electron microscopy,X-ray diffraction,N2 adsorption,X-ray photoelectron spectroscopy,UV-visible spectroscopy,and electrochemical impedance spectroscopy. Their photocatalytic activity was evaluated using the photocatalytic reduction of CO2. The N-doped TiO 2 sample exhibited a much higher visible light photocatalytic activity for CO2 reduction than its precursor TiN and commercial TiO 2（P25）. This was due to the synergistic effect of the formation of surface heterojunctions on the TiO 2 microsheet surface,enhanced visible light absorption by nitrogen-doping,and surface fluorination.

Direct electrospinning method for the construction of Z-scheme TiO_2/g-C_3N_4/RGO ternary heterojunction photocatalysts with remarkably ameliorated photocatalytic performance

A series of Z-scheme TiO2/g-C3N4/RGO ternary heterojunction photocatalysts are successfully constructed via a direct electrospinning technique coupled with an annealing process for the first time. They are investigated comprehensively in terms of crystal structure, morphology, composition, specific surface area, photoelectrochemical properties, photodegradation performance, etc. Compared with binary TiO2/g-C3N4 and single-component photocatalysts, ternary heterojunction photocatalysts show the best photodegradation performance for RhB under stimulated sunlight. This can be attributed to the enlarged specific surface area (111.41 m2/g), the formation of Z-scheme heterojunction, and the high separation migration efficiency of photoexcited charge carriers. A potential Z-scheme mechanism for ternary heterojunction photocatalysts is proposed to elucidate the remarkably ameliorated photocatalytic performance based on active species trapping experiments, PL detection test of hydroxyl radicals, and photoelectrochemical properties.

Theoretical study of NO adsorbed on the surface of TiO2（110） cluster model

The chemisorption properties of N^18O adsorption on TiO2(110) surface were investigated by experimental and theoretical methods. The results of temperature programmed desorption (TPD) indicated that the temperatures of the three desorption peaks of the main N2 molecules were at (low) temperature of 230 K, 450 K, and (high) temperature of 980 K. This meant that N^18O decomposed and recombined during the process of N2 desorption after N^18O was exposed. Analysis of thestable combination and orbital theory calculation of the surface reaction of NO adsorption on the TiO2(110) cluster modelshowed that there was clear preference for the Ti-NO orientation.

Simultaneous formation of a C/N-TiO_2 hollow photocatalyst with efficient photocatalytic performance and recyclability

Herein,we report a unique approach towards the preparation of C-modified and N-doped TiO2 hollow spheres(C/N-TiO2).TEM,SEM,and XPS analyses were used to confirm that the carbon and nitrogen co-decorated TiO2 photocatalyst was formed.Carbon-decoration improves the visible-light absorption and speeds up the separation of the photo-generated electron-hole pairs.C/N-TiO2 not only narrows the band gap of TiO2,but also exhibits excellent photocatalytic activity for the degradation of tetracycline and tetracycline hydrochloride.In addition,the C/N-TiO2 photocatalyst shows excellent recyclability for water decontamination,making it a promising candidate to purify aquatic contaminants.

Preparation of Nitrogen-doped TiO2 Nanoparticle Catalyst and Its Catalytic Activity under Visible Light

N-doped TiO2 nanoparticle photocatalysts were prepared through a sol-gel procedure using NH4C1 as the nitrogen source and followed by calcination at certain temperature. Systematic studies for the preparation parameters and their impact on the structure and photocatalytic activity under ultraviolet （UV） and visible light irra-diation were carried out. Multiple techniques （XRD, TEM, DRIF, DSC, and XPS） were commanded to characterize the crystal structures and chemical binding of N-doped TiO2. Its photocatalytic activity was examined by the deg- radation of organic compounds. The catalytic activity of the prepared N-doped TiO2 nanoparticles under visible light （λ〉400nm） irradiation is evidenced by the decomposition of 4-chlorophenol, showing that nitrogen atoms in the N-doped TiO2 nanoparticle catalyst are responsible for the visible light catalytic activity. The N-doped TiO2 nanoparticle catalyst prepared with this modified route exhibits higher catalytic activity under UV irradiation in contrast to TiO2 without N-doping. It is suggested that the doped nitrogen here is located at the interstitial site of TiO2 lattice.

Superior performance of iridium supported on rutile titania for the catalytic decomposition of N_2O propellants

N2O is a promising green propellant and exhibits great potential for satellite propulsion systems. It is difficult for catalytic decomposition, which is an important way to initiate the propulsion process, to occur at temperatures below 600 °C due to the high activation energy of N2O. In this work, we report an Ir supported on rutile TiO2（Ir/r-TiO2） catalyst which exhibits a fairly high activity for high-concentration N2O decomposition. HAADF-STEM, H2-TPR, and XPS results indicate that highly dispersed Ir particles and improved oxygen mobility on the Ir/r-TiO2 could facilitate the decompo-sition of N2O and desorption of the adsorbed oxygen. Bridge-bonded peroxide intermediates were observed with in-situ DRIFT and herein, a detailed decomposition route is proposed.

Effect of Dispersity and Porous Structure of TiO2 Nanopowders on Photocatalytic Destruction of Azodyes in Aqueous Solutions

Photocatalytic activity of TiO2 nanopowders of anatase modification with various particle sizes and specific surface areas has been studied in the process of photocatalytic decolorization of aqueous solutions of methylene blue and direct blue 2C azodyes. By means of scanning electron microscopy and low-temperature N2 adsorption method, it was found that TiO2 nanopowders have the particles size of 5-120 nm with the specific surface area of 15-120 m2·g^-1. The used TiO2 samples are characterized by mesoporous structures with average pore size of 4.3-14.9 nm. The photocatalytic activity of TiO2 was evaluated via decolorization of azodyes solutions. It was shown that the efficiency of decolorization symbatically changes with the dye adsorption value on TiO2 surface and the degree of decolorization rises when the surface area of TiO2 nanopowders increases. It was found that TiO2 photocatalytic activity essentially depends on adsorption interactions between the dye molecules and catalytic active centers on TiO2 surface, and these interactions, in turn, are greatly affected by pH of the solution.