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1.
本文在环氧涂料中添加玄武岩鳞片,提高其防腐蚀性能。针对玄武岩鳞片的团聚问题,通过机械力化学改性工艺,采用正硅酸四乙酯、HY-311型钛酸酯偶联剂、E-44型环氧树脂对玄武岩鳞片进行杂化包覆,结果表明,杂化包覆后玄武岩鳞片的沉降时间从2h提高至96 h。杂化包覆玄武岩鳞片添加量为20%涂层的性能最优,附着力为13.40 MPa,耐盐雾时间为2000 h,在3.5%NaCl溶液中浸泡2000 h后,0.01 Hz的阻抗模值仍然有5.15×109 Ω·cm2。 相似文献
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Iqbal Ahmad Syed Mujtaba Shah Muhammad Nadeem Zafar Muhammad Naeem Ashiq Wei Tang Uzma Jabeen 《Ceramics International》2021,47(3):3760-3771
Ferrites are materials of interest due to their broad applications in high technological devices and a lot of research has been focused to synthesize new ferrites. In this regard, an effort has been devoted to synthesize spinel Pr–Ni co-substituted strontium ferrites with a nominal formula of Sr1-xPrxFe2-yNiyO4 (0.0 ≤ x ≤ 0.1, 0.0 ≤ y ≤ 1.0). The cubic structure of pure and Pr–Ni co-substituted strontium ferrite samples calcinated at 1073 K for 3 h has been confirmed through X-ray diffraction (XRD). Average sizes of crystallites (18–25 nm) have been estimated from XRD analysis and nanometer particle sizes of synthesized ferrites have been further verified by scanning electron microscopy (SEM). SEM results have also shown that particles are mostly agglomerated and all the samples possess porosity. It has been observed that at 298 K, the values of resistivity (ρ) increase, while that of AC conductivity, dielectric loss, and dielectric constants decrease with increasing amounts of Pr3+ and Ni2+ ions. The values of dielectric parameters initially decrease with frequency and later become constant and can be explained on the basis of dielectric polarization. Electrochemical impedance spectroscopy (EIS) studies show that the charge transport phenomenon in ferrite materials is mainly controlled via grain boundaries. Overall, synthesized ferrite materials own enhanced resistivity values in the range of 1.38 × 109–1.94 × 109 Ω cm and minimum dielectric losses, which makes them suitable candidates for high frequency devices applications. 相似文献
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Koratagere Revanna Nagaraju Ulavathi Shettar Mahabaleshwar Muddenahalli Siddalinga Prasad Basma Souayeh 《亚洲传热研究》2022,51(6):5288-5301
This article focuses on analytic solutions for Newtonian fluid flow with slip and mass transpiration on a porous stretching sheet using the differential transform method and Pade approximants of an exceptionally nonlinear differential equation. The impacts of different parameters including mass transpiration (suction/injection), Navier's slip, and Darcy number parameters on the velocity of the liquid and tangential stress are discussed. A comprehensive comparison of our results with the previous one in the literature is made, and the results showed good agreement. An investigation is conducted of a combination of magnetic liquids that are conceivably pertinent for wound medicines, skin repair, and astute coatings for natural gadgets. It is found that there is a decrease in the velocity profiles and the boundary layer thickness for the case of suction. 相似文献
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Sofia Melchior Sonia Calligaris Marilena Marino Francesca D’Este Giorgio Honsell Maria Cristina Nicoli Nadia Innocente 《International Journal of Food Science & Technology》2022,57(5):3106-3115
This research aimed at studying the potential use of monoglyceride (MG) structured emulsions (MSEs) as delivery and protective systems for probiotic bacteria in Ricotta cheese. To this purpose, a low-fat commercial Ricotta cheese was added with MSEs formulated with milk, as water phase, and sunflower oil (MSE-SO) or anhydrous milk fat (MSE-AMF), as lipid phase. A commercial whole milk Ricotta cheese (W-RC) was considered as reference. A probiotic Lacticaseibacillus rhamnosus strain was inoculated as free cells in W-RC or embedded into the MSEs and added to the low-fat Ricotta at the same reference fat content. After physico-chemical characterisation, L. rhamnosus viability and sample destructuring behaviour upon in vitro digestion were evaluated. At the end of in vitro digestion, both W-RC and sample containing MSE-SO were unable to protect cells. By contrast, sample with AMF ensured a sufficient probiotic viability, even after 14 days of storage at 4 °C. This result was attributed to system composition and structure. During the gastric phase, the presence of caseins and MG-AMF mixed structures induced the formation of clots, entrapping and protecting cells against the acidic pH of the stomach, as confirmed by confocal micrographs and particle size. During the intestinal phase, cell viability was guaranteed by the formation of mixed micelles promoted by MG. It was demonstrated that microbial cells located near MG structures where they found protection. 相似文献
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《Ceramics International》2022,48(4):5091-5099
The impact of the addition of TiO2 nanoparticles and nanowires on the morphology, phase characteristics, contact angle, and electrochemical performance of chemically bonded phosphate ceramic coatings (CBPCs) was investigated. The chemical composition and surface morphology of the TiO2 nanoparticle and nanowire modified with and without (heptadecafluoro-1,1,2,2-tetradecyl) trimethoxysilane were characterized. Results indicated that the hydrophobic –CF2– and –CF3 groups were successfully introduced into the TiO2 nanoparticles and nanowires after modification. Corrosion resistance of CBPCs with TiO2 was evidently improved compared with that without TiO2. Such improvement was mainly due to the combined effects of low surface energy materials and micro/nano structures. In addition, CBPCs with TiO2 nanowires exhibited higher hydrophobicity and corrosion resistance than those with TiO2 nanoparticles because of the special columnar structure of the nanowires. 相似文献
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茯砖茶发酵、干燥过程中,烘房内温湿度稳定性和能源系统低能耗是保证茯砖茶品质与成本的重要因素。本文采用TRNSYS仿真与实验研究相结合的方法,对咸阳某茯砖茶厂实际使用的空气源热泵系统进行建模,通过研究各季节典型代表月烘房温湿度的波动情况,确定该空气源热泵系统在全年的运行状态是否满足工艺要求,在此基础上,对比了该系统在全年可运行季节代表月与该生产厂房早期使用的燃气锅炉系统的能耗仿真结果,对空气源热泵系统的节能与环保特性进行研究。结果表明:由于夏季送风质量流量过大且室外空气含湿量较高,7月烘房温湿度不满足工艺要求。热泵系统在1、4、10月的总标煤消耗量的平均值是锅炉系统的44.42%,平均CO2、SO2、NOx排放量分别为锅炉系统的34.13%、44.1%、40.60%。在茯砖茶发酵、干燥的过程中,相比于燃气锅炉系统,空气源热泵系统具有更好的节能与环保特性。 相似文献