JOURNAL OF MEMBRANE SCIENCE
·
2016
·
IF 5.557
Jonas Hereijgers,Heidi Ottevaere,Tom Breugelmans,Wim De Malsche
In this work, the impact of the spacer features (interpillar distance and shape) on the membrane deflection, pressure difference across the membrane, and mass transfer was studied for a flat membrane microcontactor. It was demonstrated that decreasing the interpillar distance between the circular pillars reduced membrane deflection considerably. As a consequence, also the pressure difference across the membrane decreased, which lowers the possibility of breakthrough occurring. However, this was only the case until an interpillar distance of 836 µm was reached. Decreasing the interpillar distance further, the pressure difference across the membrane again increased. This was due to the smaller gap between the pillars, resulting in a higher hydraulic resistance. However, it was demonstrated that with the use of a channel filled with radially elongated (diamond shaped) pillars and wedges the pressure difference across the membrane remained minimal at small interpillar distances (i.e. 305 µm). Finally, the effect of the membrane deflection on the mass transfer was studied. It was shown that membrane deflection can have either a positive or negative impact on the mass transfer and solvent inside the pores instead of the feed is not always beneficial when membrane deflection is taken into account. Therefore, design rules for the spacer geometry are deduced, which allows maximizing mass transport.
研究领域:
生物工程
·
化学工程
✓ 已验证
DOI
高影响因子
LAB ON A CHIP
·
2022
·Vol. 23
·期 4
·737-747
·
IF 7.517
Lihua Guo,Yuanchang Liu,Li Liu,Penghe Yin,Chong Liu,Jingmin Li
Determining the mechanism that effects embolism repair in the xylem vessels of plants is of great significance in predicting plant distribution and the screening of drought-resistant plants. However, the mechanism of perforation plates of xylem vessels in the acceleration of embolism repair is still not clear by using conventional methods of anatomy and visualization technology. Microfluidic devices have shown their ability to simulate physiological environments and conduct quantitative experiments. This work proposes a biomimetic microfluidic device to study the mechanism of perforation plates of xylem vessels in the acceleration of embolism repair. The results proffered that the perforation plates increase the rate of embolism removal by increasing the pressure differential through the vessel, and the rate of embolism removal is related to the structural parameters of the perforation plate. A combination of the perforation size, the vessel diameter and the perforation plate angle can be optimised to generate higher pressure differentials, which can accelerate the process of embolism repair. This work provides a new method for studying the mechanism of microstructures of natural plants. Furthermore, the mechanism that perforation plates accelerate embolism repair was applied to an electrochemical flow sensor for online determination of heavy metal ions. Test results of this application indicate that the mechanism can be applied in the engineering field to solve the problems of reduced sensitivity of devices, inaccuracy of analysis results and poor reaction performance caused by bubbles that are generated or introduced easily in microdevices, which paves the way for applying the theory to engineering.
研究领域:
植物生理学
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生物仿生学
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微流体技术
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植物解剖学
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环境胁迫响应
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DOI
高影响因子
Optical Materials Express
·
2024
·Vol. 14
·期 11
·2728-2739
·
IF 2.8
Chenrui Zhang,You Wu,Yanbin Li,Yanbin Li,Di Xiao,Yuanyuan Zheng,Yuanyuan Zheng,Zhitai Jia,Le Zhang,Le Zhang
As a wide-bandgap semiconductor material, α-Ga2O3 has great potential in high-power devices and deep ultraviolet photodetectors. However, for α-Ga2O3 growth by mist chemical vapor deposition (mist-CVD), the clustering of mist flow often appears, resulting in poor crystallinity and rough surface of the α-Ga2O3 films. In this study, we established a homemade mist-CVD system with a heating structure and a cuboid chamber. The effects of the pressure difference between the inlet and outlet of the reaction chamber as well as the growth temperature on α-Ga2O3 film growth were systematically investigated. High-quality α-Ga2O3 thin films with a smooth surface were prepared at 450 °C under a 80 Pa pressure difference due to the weakened clustering effect of mist flow. The surface root-mean-square (RMS) roughness of the α-Ga2O3 films was as low as 1.32 nm, and the growth rate could reach 26.9 nm/min. The transmittance was higher than 80% in the near-ultraviolet to visible light region, and the optical band gap was determined to be 5.23 eV.
研究领域:
材料科学
·
半导体物理
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Xiaoming Luo,Ke Xu,Wanrui Li,Xin Huang,Limin He
In the case of fluid flow with a low Reynolds number, the internal fluid stratification can be easily observed after droplet coalescence, impeding rapid mixing of fluid. In this study, the capillary pressure difference is increased by adjusting the droplet size and the interfacial tension, so that a strong jet can be generated, resulting in a rapid mixing. Five distinct droplet mixing modes have been found. The phase diagram of the droplet mixing modes is obtained and the transition rule of the droplet mixing modes is established on this basis. A novel energy distribution model is employed to analyze the dependence between liquid bridge expansion and jet movement of two droplets. In addition, a criterion for evaluating the mixing efficiency of droplets is presented. The results presented in this paper provide a theoretical basis and practical guidance for realizing the efficient mixing of microfluids.
研究领域:
流体力学
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微流体学
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生物医学工程
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界面科学
·
传质过程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yong Qi,Xianfei Cao,Tong Hu,Qingyu Liu,Jiahui Wang,Wensheng Zou,Shi Li,Shufen Zhang
Structural color anti-counterfeiting based on “hidden-display” generally drives from a “one input one output” mode, which makes nanophotonic cryptography too rudimentary to resist the increasing theft of information. Herein, by creating asymmetric photonic crystals (APCs), we report bidirectional competitive shape memory (CSM) and propose structural color-based “one input three outputs” 3D anti-counterfeiting strategies. The wetting-evaporation of the solvent triggers the three outputs of the structural color of APC. 3D decryption effects include solvent-wetting-induced display of source code (1st-level), solvent-evaporation-triggered structural color evolution or pseudocode interference (2nd-level), and complementary authentication of code (3rd-level). Dipole-dipole thermal reconfiguration dissipates the entropic elasticity temporarily stored in cold-programed longitudinal asymmetrical inverse opals and locks the skeleton network, appending transverse asymmetry. Such bidirectional asymmetry of the skeleton drives the solvent to generate multidimensional Laplace pressure differences (Δ P ) during wetting and evaporation, resulting in the competitive shape evolution of the macropore skeleton in both longitudinal and transverse directions. Moreover, the differential thickness of the inner inverse opal also enables such bidirectional CSM. Unprecedented 3D anti-counterfeiting techniques have been demonstrated. This work opens up new methods for stepwise editing and extracting complex structurally colored codes, providing design inspirations for high-level nanophotonic anti-counterfeiting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
·
2017
·Vol. 96
·期 5
·1647-1653
·
IF 2.209
Zhan W.,Tu J. S.,Qian X. Z.,Li J.,Liu J.
Ionic liquid used in Friedel-Crafts reaction catalytic of dialkyl diphenylamine is a green environmental method. In this paper, butyl-octyl-diphenylamine (BODPA) was synthesized by the series of 1-butyl-3-methylimidazolium chloroaluminate (BMIM-AlCl 3 ) ionic liquids catalysts. Pressure differential scanning calorimetry (PDSC) was used to test antioxidant properties of BODPA in lubricating oil. The influences of various reaction parameters such as dosage of catalysts, molar ratio of diphenylamine to chloralkane, reaction temperature, and time on the alkylation catalyzed by BMIM-AlCl 3 have been studied. The molecular structure and content of alkyl diphenylamine were also characterized by FT-IR/GC-MS.
研究领域:
化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Ji Mi,Cui Ye,Yongsheng Guo,Wenjun Fang
Two vanillic Schiff-base antioxidants, 2-methoxy-4-(((4-(phenylamino)phenyl)imino)methyl)phenol (PPIMP) and 2-methoxy-4-(((4-(phenylamino)phenyl)amino)methyl)phenol (PPAMP), have been synthesized through the Schiff-base condensation reaction and hydrogenation to improve the thermal-oxidative stability of hydrocarbon fuels. Both novel antioxidants exhibited remarkable performance in decalin and JP-10 fuel. For example, pressurized differential scanning calorimetry (P-DSC) tests showed that adding 100 ppm of PPIMP or PPAMP to JP-10 improved the oxidation induction time from 9.5 min to 19.2 and 27.8 min, respectively. JFTOT tests showed that adding 100 ppm of either antioxidant helped alleviate JP-10 deposition. Theoretical calculations on electron properties and orbital conformation revealed that the C = N bridge in PPIMP had an electron donation effect and conjugative stabilization effect, which can stabilize intermediate antioxidant radicals and improve the antioxidants’ reactivity. The hydrogenation of C = N further enhanced the performance of PPAMP by introducing an additional antioxidant group. Therefore, both C = N and C-N in the synthesized antioxidants were found to be essential. The chemical combination of small molecular antioxidants achieves 1 + 1 > 2 synergism with the assistance of the azomethine group.
研究领域:
化学
·
材料科学
·
航空航天工程
·
燃料化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）