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11.
Manipulation of micro-objects have been playing an essential role in biochemical analysis or clinical diagnostics. Among the diverse technologies for micromanipulation, acoustic methods show the advantages of good biocompatibility, wide tunability, a label-free and contactless manner. Thus, acoustic micromanipulations have been widely exploited in micro-analysis systems. In this article, we reviewed the acoustic micromanipulation systems that were actuated by sub-MHz acoustic waves. In contrast to the high-frequency range, the acoustic microsystems operating at sub-MHz acoustic frequency are more accessible, whose acoustic sources are at low cost and even available from daily acoustic devices (e.g. buzzers, speakers, piezoelectric plates). The broad availability, with the addition of the advantages of acoustic micromanipulation, make sub-MHz microsystems promising for a variety of biomedical applications. Here, we review recent progresses in sub-MHz acoustic micromanipulation technologies, focusing on their applications in biomedical fields. These technologies are based on the basic acoustic phenomenon, such as cavitation, acoustic radiation force, and acoustic streaming. And categorized by their applications, we introduce these systems for mixing, pumping and droplet generation, separation and enrichment, patterning, rotation, propulsion and actuation. The diverse applications of these systems hold great promise for a wide range of enhancements in biomedicines and attract increasing interest for further investigation. 相似文献
12.
R. Shanmugam J. Ganesamurthi T.-W. Chen S.-M. Chen M. Balamurugan M.A. Ali A.M. Al-Mohaimeed W.A. Al-onazi K. Alagumalai 《Materials Today Chemistry》2022
Herein, we reported the fabrication of porous iron oxide/carbon black (P–Fe2O3/CB) composite through a two-step engineering method. At first, Prussian blue microcubes were used as a precursor and further calcined to form P–Fe2O3 microcubes. The intercalation of CB nanoparticles with P–Fe2O3 nanocubes was processed through the ultrasonication method. The obtained P–Fe2O3/CB were successfully scrutinized through various physiochemical characterization methods. The proposed P–Fe2O3/CB-modified glassy carbon electrode sensor was successfully implemented in the electrochemical sensing of chlorpromazine hydrochloride due to its very low charge transfer resistance (Rct) compared to the other electrode modifiers. The sensitive detection of CPMH through differential pulse voltammetry exemplifies an excellent electroanalytical performance such as a wide linear range of 0.5–1472 μM, a lower detection limit (0.001 μM), and an appraisable sensitivity of 1.99 μA/μM cm?2 due to its availability of a high number of active sites and its large surface area, respectively. It also expresses excellent selectivity, repeatability, reproducibility, and stability results. Moreover, the practical feasibility of the as-fabricated P–Fe2O3/CB/glassy carbon electrode sensor shows exquisite recovery (98.1–100.8%) results with an appraisable current response in various biological, pharmaceutical, and environmental samples. 相似文献
13.
Recently Haezendonck–Goovaerts (H–G) risk measure has received much attention in (re)insurance and portfolio management. Some nonparametric inferences have been proposed in the literature. When the loss variable does not have enough moments, which depends on the involved Young function, the nonparametric estimator in Ahn and Shyamalkumar (2014) has a nonnormal limit, which challenges interval estimation. Motivated by the fact that many loss variables in insurance and finance could have a heavier tail such as an infinite variance, this paper proposes a new estimator which estimates the tail by extreme value theory and the middle part nonparametrically. It turns out that the proposed new estimator always has a normal limit regardless of the tail heaviness of the loss variable. Hence an interval with asymptotically correct confidence level can be obtained easily either by the normal approximation method via estimating the asymptotic variance or by a bootstrap method. A simulation study and real data analysis confirm the effectiveness of the proposed new inference procedure for estimating the H–G risk measure. 相似文献
14.
基于优良导体在磁场下的涡流效应理论和固体的热声效应理论,建立了氧化铟锡(ITO)导电薄膜磁-热-声效应的理论模型,推导了导电薄膜热致发声的温度振荡和输出声压表达式。对有基底的ITO导电膜进行了磁场下的热声理论计算和实验测试,结果表明:薄膜的温度振荡值随频率呈上升趋势,与电-热-声模型相比趋势相反;薄膜声压的理论值与实验值在频域内的变化趋势基本吻合,验证了理论模型的正确性。进而,根据磁-热-声的理论模型,分析了线圈相关参数对薄膜声压级的影响,结果表明:薄膜声压级随着线圈匝数的增加而增大,随着薄膜与线圈中心距离的增加而减小,随着线圈半径的增加而减小。文中的研究结果拓展了导电薄膜在扬声器等领域的应用。 相似文献
15.
以能斯特方程为基础, 通过分析电流密度与氧化还原物种活度变化, 即载流子浓度变化的关系, 计算出有机半导体材料电极电势的变化, 从而建立起有机半导体前线轨道, 即最高占据分子轨道(HOMO)能级和最低未被占据分子轨道(LUMO)能级相对于热力学平衡态的能量位移随电流密度变化的数学关系. 进而依据能级能量位移引起的能隙变化, 提出了有机电致发光显示器(OLED)中“热激子”的产生机制. 相似文献
16.
We report on the modelling of a magneto-rheological (MR) suspension bound between shearing parallel plates using a particle-level
numerical simulation. The simulation is similar to an approach used previously but includes particle hydrodynamic interaction
using elements of the Stokesian-dynamic method. Observations of initially chain-like aggregations are reported, and the evolving
morphology of suspension particle clusters is explored. Our early-strain observations concur with the prevailing ideas of
experimentalists on the important role that the microstructure has on bulk viscosity. We then study in particular the effects
of simulation size and strain on viscosity. While initial viscous response is similar to previously reported observations
in the literature, when left to run for longer strains, suspensions evolved into markedly different microstructures from those
observed experimentally, or in electro-rheological suspensions, or MR simulations with artificial wall interaction. Substantial qualitative and quantitative divergence was observed over long strains. We argue
that this divergence is due to the lack of a particle–wall interaction model for MR fluids. While current theories in MR modelling
do not justify the requirement for a particle–wall interaction, these results suggest that one is required in order to match
experimental observations.
相似文献
C. G. JoungEmail: |
17.
M. Sadatomi M. Kawaji C.M. Lorencez T. Chang 《International Journal of Multiphase Flow》1993,19(6):987-997
A one-dimensional momentum equation has been derived based on a two-fluid model and used to predict the axial distribution of liquid level or void fraction in steady, cocurrent, gas-liquid stratified flows in horizontal circular pipes and rectangular channels. The equation is carefully formulated to incorporate the effect of interfacial level gradient. Two different critical liquid levels are found from the momentum equation and are adopted as a boundary condition to calculate the liquid level or void fraction distribution upstream of the channel exit. The predicted void fraction distributions are compared with the experimental data obtained in a rectangular channel in this work and other data reported for large-diameter pipes. Good agreement is shown for air-kerosene, air-water and stream-water stratified flows with a smooth gas-liquid interface. 相似文献
18.
19.
磁粉法检测表面裂纹概率曲线的测定 总被引:1,自引:0,他引:1
本文介绍了利用实物零件测定裂纹检出概率的方法,并作出了用磁粉法检测表面裂纹的检测概率曲线,为大型构件检测周期的确定提供了可靠数据,为结构损伤容限设计,可靠性设计提供了重要的依据。 相似文献
20.
二维边界元奇异积分和多域缩聚法分析 总被引:2,自引:1,他引:2
基于基本解的一种新的表达式,对二维边界元分析中奇异积分的精确求解进行了讨论,从几何方面对基本解的奇异性进行了分析,给出了超参非连续元离散位势和弹性力学问题边界积分方程时奇异积分计算的精确式,从而为判断各种近似方法的优劣和间接方法的精度提供了依据,也为精确地分析了大规模问题提供了一条有效的途径。 相似文献