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1.
《Ceramics International》2022,48(1):495-502
Preparation and growth mechanism of anodization of Ti and Al has been widely concerned for two decades, but the research on anodic ZrO2 is relatively lacking. In this paper, anodic TiO2 and ZrO2 nanotubes were prepared in glycerol electrolyte containing 0.35 M NH4F and 4 vol% H2O under different anodizing voltages. We had successfully prepared the anodic ZrO2 nanotubes (AZNTs) with a complete top and a “bulb” at the bottom under 60 V, and with the increase of the applied anodizing voltage, the “bulb” cavity also increased. However, under the same anodizing conditions, the surface of anodic TiO2 nanotubes (ATNTs) is a cluster of nano-tip morphology, and the bottom of the ATNTs is a conventional hemisphere shape. In addition, both AZNTs and porous anodic zirconia (PAZ) were found to coexist in the anodic ZrO2 layer prepared at 60 V. Here, we used the oxygen bubble model and ionic current and electronic current theories to analyze the reason of the special morphology. It is confirmed that the porous anodic oxides are actually evolved from nanotubes. In other words, the structure is essentially the same. 相似文献
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在发泡塑料的制造过程中,均相气体-聚合物体系的形成直接影响了制品的物理机械性能,因此了解气泡在粘弹性液体中的溶解机理成为必然。本文讲述了气泡在流体中塌陷行为的研究进展。对Rayleigh对低粘度牛顿流体,Foqer和Goddand在无线量线性Maxwell模型的粘弹性体,Tanasawa和Tang用oldroyd三常数粘弹模型等科学家的研究行为做了概述,总结出影响此过程的复杂的影响因素,并指出进一步的研究方向。 相似文献
5.
Wei Feng Jianping Wen Xiaoqiang Jia Qing Yuan Yan Sun Cuiyun Liu 《American Institute of Chemical Engineers》2006,52(8):2864-2875
A coupled three-dimensional (3-D) model, combining hydrodynamics with biochemical reactions, was developed to simulate the local transient flow patterns and the dynamic behaviors of cell growth and phenol biodegradation by yeast Candida tropicalis in the bubble-column bioreactor, using the computational fluid dynamic (CFD) method. In order to validate this proposed model effectively, the validation of the local hydrodynamic characteristics of the gas-mineral salt solution (gas-liquid) two-phase system, with the phenol concentration of 1200 mg/L, and with the absence of cells, was performed in a square-sectioned bubble column bioreactor using the LDA system and conductivity probe. Furthermore, the validation of phenol biodegradation behaviors by yeast Candida tropicalis at different initial concentrations of phenol and cell was also carried out in the above bubble-column bioreactor. The results indicated that the model simulations had a satisfying agreement with the experimental data. Finally, the local instantaneous flow and phenol biodegradation features including gas holdup, gas velocity, liquid velocity, cell concentration and phenol concentration inside the bioreactor were successfully predicted in different-scale bubble columns by the proposed model. © 2006 American Institute of Chemical Engineers AIChE J, 2006 相似文献
6.
防腐蚀施工工艺掌握的好坏,直接影响到工程投入生产后的使用寿命,为保证工程质量,以太钢不锈冷轧改造工程冷线防腐为例,对其常发生的质量通病进行认真分析,总结出一套行之有效的施工技术。 相似文献
7.
Boiling: Size Distribution of Bubbles as Demanded by the Principle of Maximum Information 总被引:1,自引:0,他引:1
The principle of maximum informational entropy is used to find the probability density function for the departure radius of a bubble in boiling on a solid surface. A general relation is derived, which leads to particular expressions. 相似文献
8.
NucleatePoolBoilingofPureLiquidsandBinaryMixtures:PartI-AnalyticalModelforBoilingHeatTransferofPureLiquidsonSmoothTubesGuoqin... 相似文献
9.
Denis Rodrigue 《加拿大化工杂志》2002,80(2):289-292
Recently, the author (Rodrigue, 2001 a, b) proposed a generalized correlation for the steady rise of gas bubbles in uncontaminated viscous Newtonian fluids of infinite extent. It is the purpose of this note to show that this model can be modified for inelastic non‐Newtonian power‐law fluids. Using data taken from six different studies, it is shown that the modified model can predict quite nicely the bubble velocity for these non‐Newtonian inelastic fluids. 相似文献
10.
浅谈气泡混合轻质土的特点及应用 总被引:1,自引:0,他引:1
结合高速公路的发展,分析了气泡混合轻质土的设计机理,详细地介绍了气泡混合轻质土的工程特性,阐述了气泡混合轻质土在公路建设中的应用,最后对气泡混合轻质土的应用前景进行了展望。 相似文献