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41.
《Ceramics International》2023,49(18):30335-30346
The design and development of efficient approaches for water–oil separation have had widespread interest. This study aimed to synthesize nanocomposites based on Ti(OH)4 and g-C3N4 nanosheets (CN-NS) to show experimentally that the inclusion of Ti(OH)4 nanoparticles of 9.2 nm size into CN-NS leads to an improved oil-water separation efficiency and anti-fouling performance. So, a novel, reusable, and recyclable super-hydrophilic/underwater super-oleophobic CN-NS/Ti(OH)4 nanocomposite-coated stainless steel mesh was developed to separate oil-in-water emulsions. Super-wettability was obtained in the CN-NS/Ti(OH)4 nanocomposite with WCA = 0° and UOCA = 154°, respectively, showing significant super-hydrophilicity and underwater super-oleophobicity. Surface hydrophilicity increased after anchoring Ti(OH)4 on the CN-NS surface, resulting from oxygen-containing functional groups and consequently making defects on the mesh surface. Enhanced underwater oleophobicity of nanocomposite coated mesh is attributed to its higher surface roughness, which is a result of its micro-nano meter and mesoporous hierarchical structure. Moreover, the self-cleaning property of the as-prepared mesh was demonstrated by visible light irradiation on the contaminated mesh. In addition, perfluorooctanoic acid (PFOA) reduced energy in CN-NS/Ti(OH)4/PFOA mesh, resulting in a super-hydrophilic/super-oleophobic mesh. The CN-NS/Ti(OH)4/PFOA nanocomposite-coated filter was observed to separate water from a 1 wt% water-in-oil emulsion at 0.2 bar pressure with a filtration flux of 317.2 L m−2 h−1 and 95% separation efficiency. 相似文献
42.
《Journal of the European Ceramic Society》2023,43(15):6883-6892
A facile tartaric acid assisted method using metatitanic acid, barium hydroxide and tartaric acid as starting materials is proposed to prepare tetragonal BaTiO3 fine powders. Owing to the ultrafine character of the as-formed BaCO3 with high chemical activity, and its arrangement coating the surface of intermediate TiO2 nanoscale needles, pure cubic phase BaTiO3 homogeneous powders with size of about 50 nm was obtained via calcining treatment at 650 ℃, which subsequently transformed as tetragonal BaTiO3 uniform powders with size of about 240 nm and high tetragonality (c/a=1.0095) after calcining treatment at 1050 ℃. The BaTiO3 ceramic prepared from the BaTiO3 uniform powders displayed much improvement performances with high permittivity of about 5980 and low dielectric loss of about 0.014 at room temperature in comparison to the BaTiO3 ceramic prepared respectively from the BaTiO3 synthesized via a traditional solid-state method, and commercial BaTiO3, suggesting it’s compatible in application of MLCCs with high performance. 相似文献
43.
Shih-Hao Wang Yin-Lai Chai Wen-Hsi Lee 《Journal of the European Ceramic Society》2012,32(8):1711-1723
In this study, a novel sintering technique combining rapid heating and constrained sintering was adopted to fire multilayer ceramic capacitors (MLCCs). It was demonstrated that chamber development can be significantly minimized, leading to a small internal residual stress in MLCCs when they were fired by the novel sintering technique instead of free sintering. The magnitude of tensile stress was closely related to the heating rate and the thickness of the constraining layer. The presence of in-plane tensile stress resulted from the constrained sintering in the x–y plane of the MLCCs, which then modified both the densification rate of the dielectric materials and the inner electrode. The thin inner electrode (<1 μm) with high continuity (>98%) and the fine grain size (1.5 μm) with narrow distribution (±0.10 μm) of BCTZ-based MLCC with a concave-free morphology can be attained by using such a rapid constrained sintering technique when BT is used as a constraining layer laminated on both sides of the multilayer BCTZ-based MLCC. 相似文献
44.
45.
2个Smarandache LCM函数的混合均值估计 总被引:1,自引:0,他引:1
黄炜 《纺织高校基础科学学报》2011,24(3):390-393
研究了Smarandache LCM函数SL(n)与r角形数函数ur(n)和vr(n)的混合均值问题.利用初等方法和解析方法,给出了2个有趣的渐近公式,发展了F.Smarandache教授在《Only Problems,Not Solution》中涉及的相关研究工作. 相似文献
46.
Ab-initio computer simulations have been used to predict the energies associated with the accommodation of H atoms at interstitial sites in α, β-Zr and Zr–M intermetallics formed with common alloying additions (M = Cr, Fe, Ni). Intermetallics that relate to the Zr2(Ni,Fe) second phase particles (SPPs) found in Zircaloy-2 exhibit favourable solution enthalpies for H. The intermetallic phases that relate to the Zr(Cr,Fe)2 SPPs, found predominantly in Zircaloy-4, do not offer favourable sites for interstitial H. It is proposed that Zr(Cr,Fe)2 particles may act as bridges for the migration of H through the oxide layer, whilst the Zr2(Ni,Fe)-type particles will trap the migrating H until these are dissolved or fully oxidised. 相似文献
47.
电化学处理高浓度有机废水的研究进展 总被引:1,自引:0,他引:1
随着现代工业的迅速发展,工业废水的排放量日益增加。这给人们的生活和生产带来了极大的危害。尤其是工业高浓度有机废水,其毒性高,对环境污染大,因而其废水的处理技术受到了广泛的关注。电化学方法具有容易控制,容易建立密闭循环且无二次污染等优点,在处理有机废水方面受到广泛关注,应用很广。文章介绍了高浓度有机废水的各种电化学处理方法的机理及研究进展,并指出了今后的研究发展 相似文献
48.
Nicolette Pegels Isabel González Irene Martín María Rojas Teresa García Rosario Martín 《Food Control》2011,22(8):1189-1196
A TaqMan real-time polymerase chain reaction (PCR) method was developed for specific detection of bovine, ovine and caprine processed animal protein (PAP) in industrial feedstuffs. The method uses species-specific primers and probes targeting short mitochondrial D-loop sequences, and a positive amplification control based on 18S rRNA gene. The applicability of the real-time PCR protocol was assessed through analysis of 126 industrial feed samples that were manufactured to reproduce rendering processes of commercial feeds destined for farmed animals. The assay successfully classified samples as positive or negative according to the ruminant composition, enabling qualitative detection of banned material in feeds at levels as low as 0.1%. Although the method provides quantitative potential, results suggest that the real quantitative capability of the assay is limited by the existing variability in terms of composition and processing treatments of the feeds, which affect the amount and quality of amplifiable DNA. 相似文献
49.
50.
《Minerals Engineering》2007,20(12):1153-1158
Platinum arsenide minerals are important platinum carriers in altered platinum reserves such as the Great Dyke of Zimbabwe and the Platreef (in the Bushveld Complex of South Africa). Industrial mineralogical investigations suggest these minerals to be poorly recovered during froth flotation and are believed to be slow floating. In this work, electrochemical investigations, electrochemical contact angle measurements and Raman spectroscopy have been employed to investigate the interaction of ethyl xanthate with synthetic PtAs2. The electrochemical investigations suggest a strong interaction of the xanthate with the mineral at potentials higher than the reversible potential of the xanthate–dixanthogen couple. Raman spectroscopy has confirmed the presence of dixanthogen on the mineral surface when the surfaces are anodically polarized. Contact angle investigations indicated the surface to be hydrophobic; possible mechanisms of the slow floating behaviour are discussed. 相似文献