检索结果-南通市图书馆

Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： Xing-Xing Qiao Yu-Hang Xu Xiang-Ji Liu Sai-Le Chen Zhou Zhong Ya-Feng Li Jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment technologies.Herein,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton processes.Due to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses.This work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

Effect of titanium dioxide Nanoparticles on Growth and Biomass Accumulation in Lettuce (Lactuca sativa)

在线全文

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2024年第1期15卷 1-13页

作者： Channa B. Rajashekar Brenden Armstrong Department of Horticulture and Natural Resources Kansas State University Manhattan KS USA

The use of titanium dioxide nanoparticles (nTiO2) is gaining interest in agriculture because of their impact on many aspects of plant growth. The present study examines the effects of nTiO2 (5 nm and 10 nm) applied to seeds and the seedlings as a foliar application on various aspects of growth characteristics and biomass accumulation in lettuce (Lactuca sativa, cv. Grand Rapids). Application of 10 nm nTiO2 to seeds through imbibition resulted in a significant reduction in shoot biomass accumulation while 5 nm nTiO2 did not affect the biomass accumulation in lettuce. The application of 10 nm nTiO2 reduced the fresh shoot biomass accumulation by about 18% compared to the control plants. Other growth characteristics such as shoot dry biomass, root fresh and dry biomass, plant height, and leaf area were not affected by the application of both 5 nm and 10 nm nTiO2. In addition, foliar application of these nanoparticles to the lettuce seedlings did not have a significant effect on most of the growth parameters examined, and the increasing concentration ranging from 5 nm/L to 400 mg/L did not produce a consistent response in lettuce. Thus, nTiO2 application to lettuce seeds had a notable negative impact on shoot growth while foliar application did not have a significant effect on many plant growth characteristics. However, foliar applications produced some symptoms of toxicity to the foliage in the form of necrotic or chlorotic patches on the leaves, which were more pronounced with increasing concentrations of both 5 nm and 10 nm nTiO2. However, these symptoms were apparent at a concentration as low as 50 mg/L of nTiO2. Thus, foliar application of nTiO2 may not have a significant impact on many of the growth characteristics in lettuce, but it can result in foliar toxicity.

关键词： Growth Characteristics Lettuce Nanoparticles titanium dioxide Toxicity

A novel method for fast and continuous preparation of superfine titanium dioxide nanoparticles in microfluidic system

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2022年第1期20卷 61-67页

作者： Nan Deng Yujun Wang Guangsheng Luo State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Previously we had developed a microfluidic system that can be easily fabricated by bending a stainless-steel tube into large circular loops.In this study,a fast and continuous preparation method for superfine TiO_(2) nanoparticles(TiO_(2)-NPs)was developed for the aforementioned microfluidic system.The proposed method can yield anatase TiO_(2) in 3.5 min,in contrast to the traditional hydrothermal reaction method,which requires hours or even days.Different reaction conditions,such as reaction temperature(120-200℃),urea concentration(20-100 g/L),and tube length(5-20 m)were investigated.X-ray diffraction and Brunauer-Emmett-Teller analysis indicate that the as-prepared TiO_(2)-NPs have crystalline sizes of 4.1-5.8 nm and specific surface areas of 250.7-330.7 m^(2)/g.Transmission electron microscopy images show that these TiO_(2)-NPs have an even diameter of approximately 5 nm.Moreover,because of their small crystalline sizes and large specific surface areas,most of these as-prepared TiO_(2)-NPs exhibit considerably better absorption and photocatalytic performance with methylene blue than commercial P5 TiO_(2) does.

关键词： titanium dioxide Microfluidic system Nanoparticles Fast preparation Superfine

Study on Air-Purifying Performance of Semi-Flexible Asphalt Samples Coated with titanium dioxide Using Different Methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2022年第5期10卷 1321-1335页

作者： Shoujing Yan Yangyang Wang Fengxia Chi Xue Luo Tianjie Zhang Chenchen Xi Institute of Road Engineering Zhejiang Scientific Research Institute of TransportHangzhou310023China Department of Architecture and Civil Engineering Zhejiang UniversityHangzhou310027China Department of Computer Science Boise State UniversityBoise83725-1145USA

titanium dioxide(TiO_(2))was recently employed to apply onto road surfaces to degrade the harmful compounds from vehicle emissions.However,it remains a challenging task to find a highly compatible pavement type for TiO_(2)application to achieve durable and efficient air-purifying performance.This study proposed to coat TiO_(2)particles onto semi-flexible pavement surface and tried to investigate an optimum coating method.Three coating methods,including direct mixing TiO_(2)(MT)with asphalt mixture,spraying dry TiO_(2)(ST)coating and watersolution-based TiO_(2)(WT)coating on semi-flexible pavement surface.To achieve this objective,semi-flexible samples were prepared to evaluate and compare the performances of three coating methods by employing resistance to wearing,NO removal efficiency tests and residual texture depth tests.It was found that the ST method not only provided better NO degrading efficiency but also improved the resistance to wearing than the other two methods.

关键词： titanium dioxide air-purifying performance semi-flexible pavement coating methods

MoO_(x) nanoclusters on Mo-doped TiO_(2) nanosheets with enhanced singlet oxygen generation and sulfide conversion abilities for photocatalytic aerobic oxidative desulfurization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第1期67卷 408-414页

作者： Suting Xie Xinyu Zhao Dongxiao Wang Huawei Yang Lixia Yang Liangjiu Bai Donglei Wei Wenxiang Wang Ying Liang Hou Chen Shaojun Guo College of Chemistry and Materials Science Ludong UniversityYantai 264025China College of Materials Science and Engineering Peking UniversityBeijing 100871China

Photocatalytic aerobic oxidation desulfurization(PAODS)is a promising and sustainable alternative to conventional,energyintensive desulfurization techniques for petroleum products.However,its development is greatly plagued by the low capability in generating highly reactive oxygen species and sluggish kinetics of sulfide oxidation of reported photocatalysts.Here we report a class of MoO_(x)nanocluster decorated on ultrathin Mo-doped TiO_(2)nanosheet(MoO_(x)/MoTiO)catalyst for efficiently facilitating the photocatalytic aerobic oxidation of sulfides.We demonstrate that MoO_(x)/MoTiO can not only promote the generation of highly reactive singlet oxygen(^(1)O_(2))but also enhance the aerobic conversion of sulfides,which leads to a record dibenzothiophene oxidation activity of 3.90 mmol g^(-1)h^(-1).The multiple experimental characterizations and density functional theory calculations collectively reveal that the doped-Mo sites can interact with the photogenerated excitons,enabling directly energy transfer generation of^(1)O_(2)through a new exciton modulation mechanism,and the coordination unsaturated MoO_(x)clusters play the role of co-catalyst to enhance the separation of charge carriers,and effectively catalyze the reaction between sulfides and1O_(2)to form sulfones.

关键词： titanium dioxide photocatalytic aerobic oxidation desulfurization dibenzothiophene singlet oxygen

titanium dioxide Nanoparticle Absorbed by Hepatoma Cells in Vitro

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 31-34页

作者：扈盛李世普 Biomedical Materials and Engineering Center Wuhan University of Technology

It is reported thut nanoporticles can be applied as carriers and anti-cancer medicines. But the interaction of nanoparticles and cells is unclear. The purpose of this study was to discuss whether inorganic crystal nanoparticles can get through cells with intact crystal. BEL7402 heputoma cells and titanium dioxide （ TiO2 ） nanoporticles were selected and incubated together in vitro. All specimens were prepared and observed under a traasmission electron mieroscope （TEM）. TiO2 nanopartieles were found not in the nuclear area but in the cytoplasma. TiO2 nanoponieles maintained the plate-like shape during absorbing. The result shows that hepatoma cells can endocytose the intact TiO2 crystal nanoparticles. It implies that novel nano-effect plays an important role in the biomedicinal application of inorganic crystal nanopartieles.

关键词： titanium dioxide nanoparticle hepatoma cell in vitro

Dissolution behavior of Al_(2)O_(3)inclusions into CaO-MgO-SiO_(2)-Al_(2)O_(3)-TiO_(2)system ladle slags

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 977-987页

作者： Zhiyin Deng Xiaomeng Zhang Guangyu Hao Chunxin Wei Miaoyong Zhu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China TBEA Shenyang Transformer Group Co. Ltd.Shenyang 110141China Angang Steel Co. Ltd.Anshan 114021China

To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)contents(0-10wt%),and scanning electron microscopy was performed to study the interfacial reaction between Al_(2)O_(3)and this slag system.The results disclose that the dissolution of Al_(2)O_(3)inclusions does not result in the formation of new phases at the boundary between the slag and the inclusions.In TiO_(2)-bearing and TiO_(2)-free ladle slags,there is no difference in the dissolution mechanism of Al_(2)O_(3)inclusions at steelmaking temperatures.Boundary layer diffusion is found as the controlling step of the dissolution of Al_(2)O_(3),and the diffusion coefficient is in the range of 4.18×10^(-10)to 2.18×10^(-9)m^(2)/s at 1450-1500℃.Compared with the solubility of Al_(2)O_(3)in the slags,slag viscosity and temperature play a more profound role in the dissolution of Al_(2)O_(3)inclusions.A lower viscosity and a lower melting point of the slags are beneficial for the dissolution.Suitable addition of TiO_(2)(e.g.,5wt%)in ladle slags can enhance the dissolution of Al_(2)O_(3)inclusions because of the low viscosity and melting point of the slags,while excessive addition of TiO_(2)(e.g.,10wt%)shows the opposite trend.

关键词： inclusions dissolution ladle refining slag titanium dioxide confocal scanning laser microscopy

Photocatalytic degradation of Chicago Sky Blue 6B and Benzopurpurin 4B using titanium dioxide thin film

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2005年第5期17卷 869-872页

作者： Abdul K. Mohammed Katrina T. McKenzie Department of Chemistry Winston-Salem State UniversityDepartment of Chemistry North Carolina Agricultural and Technical State University 601 S. Martin Luther King Jr. Drive Winston-Salem North Carolina 27110 USA1601 E. Market Street Greensboro North Carolina 27411 USA

Aqueous solutions of azo dyes undergo degradation to form harmless intermediates and colorless products following irradiation by visible light in the presence of titanium dioxide thin films. The dyes that were studied in this work are： Chicago Sky Blue 6B and Benzopurpurin 4B. Results obtained indicated that complete mineralization of the dyes took place under the experimental conditions. There was an increase in conductivity after the complete mineralization experiments possibly indicating the formation of ions such as NO3^- and SO4^2-. Chemical oxygen demand（COD） measurements show a decrease in organic matter for both dyes following complete degradation. The effect of how changing experimental conditions such as pH, temperature and starting concentrations of dyes affected the rate of dye degradation was measured. There was an increase in the rate of disappearance of the dye color at lower pH. High concentrations of dye solutions reauired Iona dearadation time.

关键词： titanium dioxide photocatalysis photocatalytic degradation azo dyes

Bioactivation of titanium dioxide scaffolds by ALP-functionalization

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2017年第2期2卷 108-115页

作者： A.Sengottuvelan P.Balasubramanian J.Will A.R.Boccaccini Department of Materials Science and Engineering Institute of BiomaterialsUniversity of Erlangen-NurembergCauerstraße 691058 ErlangenGermany

Three dimensional TiO2 scaffolds are receiving renewed attention for bone tissue engineering (TE) due totheir biocompatibility and attractive mechanical properties. However the bioactivity of these scaffolds iscomparatively lower than that of bioactive glass or hydroxyapatite (HA) scaffolds. One strategy toimprove bioactivity is to functionalize the surface of the scaffolds using biomolecules. Alkaline phosphatase(ALP) was chosen in this study due to its important role in the bone mineralization process. Thecurrent study investigated the ALP functionalization of 3D titanium dioxide scaffolds using selfpolymerizationof dopamine. Robust titanium scaffolds (compressive strength^2.7 ± 0.3 MPa) wereproduced via foam replica method. Enzyme grafting was performed by dip-coating in polydopamine/ALPsolution. The presence of ALP was indirectly confirmed by contact angle measurements and enzymaticactivity study. The influence of the enzyme on the bioactivity, e.g. hydroxyapatite formation on thescaffold surface, was measured in simulated body fluid (SBF). After 28 days in SBF, 5 mg ALP coatedtitania scaffolds exhibited increased hydroxyapatite formation. It was thus confirmed that ALP enhancesthe bioactivity of titania scaffolds, converting an inert bioceramic in an attractive bioactive system forbone TE.

关键词： Alkaline phosphatase titanium dioxide Scaffolds Polydopamine Surface modification Bioactivity

Tuning the reactivity of TiO_(2)layer with uniform distribution of Sub-5 nm Fe_(2)O_(3)particles via in situ voltage-assisted oxidation for robust catalytic reduction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Materials Science 2024年第2期6卷 223-234页

作者： Nisa Nashrah Abdelkarim Chaouiki Wail Al Zoubi Young Gun Ko Integrated Materials Chemistry Laboratory School of Materials Science and EngineeringYeungnam UniversityGyeongsan38541Republic of Korea

The trade-off between efficiency and stability has limited the application of TiO_(2)as a catalyst due to its poor surface reactivity.Here,we present a modification of a TiO_(2)layer with highly stable Sub-5 nm Fe_(2)O_(3)nanoparticles(NP)by modulating its structure-surface reactivity relationship to attain efficiency-stability balance via a voltage-assisted oxidation approach.In situ simultaneous oxidation of the Ti substrate and Fe precursor using high-energy plasma driven by high voltage resulted in uniform distribution of Fe_(2)O_(3)NP embedded within porous TiO_(2)layer.Comprehensive surface characterizations with density functional theory demonstrated an improved electronic transition in TiO_(2)due to the presence of surface defects from reactive oxygen species and possible charge transfer from Ti to Fe;it also unexpectedly increased the active site in the TiO_(2)layer due to uncoordinated electrons in Sub-5 nm Fe_(2)O_(3)NP/TiO_(2)catalyst,thereby enhancing the adsorption of chemical functional groups on the catalyst.This unique embedded structure exhibited remarkable improvement in reducing 4-nitrophenol to 4-aminophenol,achieving approximately 99%efficiency in 20 min without stability decay after 20 consecutive cycles,outperforming previously reported TiO_(2)-based catalysts.This finding proposes a modified-electrochemical strategy enabling facile construction of TiO_(2)with nanoscale oxides extandable to other metal oxide systems.

关键词： titanium dioxide Oxide nanoparticle Electrochemical oxidation Surface reactivity Efficiency Stability