Synthesis and photocatalytic activity of ring-like anatase TiO2 with {001} facts exposed

Developing photocatalysts with specific morphology and good photocatalytic activities promises good opportunities to discover the geometry-dependent properties. In the present work, ring-like anatase TiO₂ with dominant {001} facets exposed were successfully synthesized via a one-pot solvothermal process of tetrabutyl titanate and hydrofluoric acid solution at 180 °C for 8 h. We found that hydrofluoric acid plays an important role in the formation of ring-like TiO₂. The morphology and microstructure were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller N₂ gas adsorption–desorption isotherms. The photocatalytic activity was evaluated by photocatalytic oxidation degradation of methylene blue aqueous solution under UV light. Results showed that ring-like TiO₂ with {001} facets exposed exhibited an excellent photocatalytic activities due to its unique structure: Nanosheets with hole.     

择优取向对氢化TiO2纳米管阵列电化学性能的影响

氢化TiO_2纳米管阵列具有良好的电化学性能,通过构筑TiO_2001取向结构可进一步提高氢化TiO_2纳米管阵列的电化学性能。本研究以Ti为基底,通过调节阳极氧化法醇-水配比及高温退火工艺的方法制备了具有不同取向程度的锐钛矿型TiO_2纳米管阵列,并对具有不同取向度的TiO_2纳米管阵列进行相同工艺参数电化学氢化处理,利用SEM、XPS、XRD、TEM及电化学测试等表征手段研究了制备工艺对取向结构的影响以及取向结构对氢化TiO_2纳米管阵列电化学性能的影响规律和作用机理。具有高度001择优取向结构的氢化TiO_2纳米管阵列放电比容量达到了17.31mF·cm~(-2),其优异的电化学性能主要归功于氢化与取向结构的协同效应。     

鼠李糖乳杆菌HN001菌株水平快速定量方法的建立及应用

目的 应用实时荧光定量聚合酶链式反应(real-timefluorescencequantitativepolymerasechainreaction,qPCR),建立鼠李糖乳杆菌HN001菌株水平的快速定量检测方法。方法 通过比对鼠李糖乳杆菌HN001的近缘菌株的基因组,筛选出鼠李糖乳杆菌HN001菌株水平的特异基因,以菌株水平的特异基因为靶标设计引物及探针,优化反应体系和条件,建立鼠李糖乳杆菌HN001株水平的q PCR检测方法。对方法的特异性、灵敏度、检出限进行验证,并采用已建立的q PCR方法进行模拟添加样品和实际样品的检测。结果 所建立的方法特异性强,与近缘菌株无交叉反应,鼠李糖乳杆菌HN001纯培养液检出限为102 CFU/mL,灵敏度可达到650 copies/μL,可在2h内完成样品检测。对模拟添加样品以及实际样品检测中q PCR和平板计数法结果的对数值进行显著性分析检验,两种方法的测定值结果均无显著性差异(P>0.05)。结论 本研究建立的q PCR检测方法可有效应用于益生菌产品中鼠李糖乳杆菌HN001菌株水平定量检测,具有快速、灵敏、准确的特点。     

Preparation of highly (001)-oriented α-Fe2O3 film on Si-substrate from drop coated BaFe12O19 via barium diffusion-induced transformation

Oriented iron oxide structure is of particular importance in electronic, magnetic, and catalytic applications. We report on a facile route to prepare (001)-oriented hematite (α-Fe₂O₃) film on a silicon substrate with drop coated BaFe₁₂O₁₉ nanoplates from hydrothermal process as precursor. The obtained α-Fe₂O₃ film displays an ultrahigh (001) orientation of 99.4% when treated at 1300 °C for 5 h. Transformation of BaFe₁₂O₁₉ into α-Fe₂O₃ is driven by directional diffusion of barium into the interface between BaFe₁₂O₁₉ coating and the substrate, where a thermodynamically stable barium silicate was produced. Given the structural similarity between BaFe₁₂O₁₉ and α-Fe₂O₃, the crystallographic direction of BaFe₁₂O₁₉ [001] is topologically converted into α-Fe₂O₃ [001] during the transformation. The ultrahigh degree of orientation of the α-Fe₂O₃ film is attributed to the large aspect ratios of the starting BaFe₁₂O₁₉ nanoplates, which facilitate the realignment of plates, causing them to flatten on the substrate during heat treatment.     

Photocatalytic oxidation of toluene to benzaldehyde over anatase TiO2 hollow spheres with exposed {001} facets

A new series of anatase TiO₂ hollow structures were prepared by a facile hydrothermal process. When the hydrothermal time was increased from 20 min to 72 h, the resulting TiO₂ solid spheres gradually transformed into TiO₂ hollow spheres with higher surface crystallinity and exposed {001} facets. The as-prepared TiO₂-72 h sample exhibited the highest activity comparing to other TiO₂-based samples and commercial product Degussa P-25 towards the selective photocatalytic oxidation of toluene to benzaldehyde. Such great photocatalytic performance was mainly attributed to enhanced UV-adsorption and better charge separation efficiency due to higher surface crystallinity of TiO₂-72 h.     

CH001皮带抑尘装置在辛置洗煤厂一车间的应用

为解决洗煤厂原煤胶带输送物料、破碎机和振动筛生产时车间内产生大量煤(粉)尘,严重威胁岗位操作人员的身体健康,且影响大型仪表、电机等设备正常使用的问题,采用了CH001皮带抑尘装置,从而有效地控制了煤(粉)尘形成的污染。     

Micro-raman study of the damage in nanopatterned GaAs(001)

A single-point diamond machine fabricated patterns with a series of equispaced lines in an area of nominally 10 μm × 10 μm. On a single GaAs wafer, patterns having 80, 100, 120, and 140 lines were machined. Sample patterns were formed with 5-mg and 7-mg loads. Atomic force microscopy (AFM) characterized the surface morphology and depth of cut of these patterns as a function of load and indicated a consistent depth of cut for a given load. Subsurface damage in these layers was compared using the ratio of the TO to the LO phonon peak intensities in the μ-Raman spectra with and without annealing.     

Self‐Assembled InAs Quantum Dots on InP(001) for Long‐Wavelength Laser Applications

Self‐assembled InAs quantum dots (QDs) embedded in an InAlGaAs matrix were grown on an InP (001) using a solid‐source molecular beam epitaxy and investigated using transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. TEM images indicated that the QD formation was strongly dependent on the growth behaviors of group III elements during the deposition of InAlGaAs barriers. We achieved a lasing operation of around 1.5 µm at room temperature from uncoated QD lasers based on the InAlGaAs‐InAlAs material system on the InP (001). The lasing wavelengths of the ridge‐waveguide QD lasers were also dependent upon the cavity lengths due mainly to the gain required for the lasing operation.     

Tamoxifen-encapsulated vesicular systems: cytotoxicity evaluation in human epidermal keratinocyte cell line

Aim: Tamoxifen is a nonsteroidal estrogen receptor modulator indicated in the treatment of breast cancer. Apoptosis has been reported to be a major mechanism for its antitumor effect. Tamoxifen has also shown significant potential in treating various dermatological disorders including psoriasis, characterized by hyperproliferation of epidermal keratinocytes. An endeavor was made in the current studies to investigate the potency of vesicle-encapsulated tamoxifen on human epidermal keratinocyte cell lines. Methods: Drug was encapsulated in the phospholipid-based vesicular systems, namely, conventional liposomes and flexible-membrane liposomes. In vitro cytotoxicity evaluation of the formulations was carried out employing MTT cell proliferation assay. Results: A composition-dependent strong inhibition in the viability of epidermal keratinocyte cells was observed. Conclusion: The encouraging findings of this work construe immense potential of the tamoxifen-encapsulated vesicular systems in the management of psoriasis.