Magnetofluidic control of the breakup of ferrofluid droplets in a microfluidic Y-junction

Polyethylene glycol (PEG) particles were prepared using low-temperature supercritical assisted atomization (LTSAA) with carbon dioxide as the spraying medium or the co-solute and acetone as the solvent. The effects of several key factors on the particle size were investigated. These factors included the concentration of the PEG solution, precipitator temperature, saturator temperature, ratio of the volumetric flow rate of carbon dioxide to the PEG solution, and the molecular weight of PEG. Spherical and non-aggregated PEG particles, with a mean size of 1.7–3.2 µm, were obtained in this study. The optimal conditions to produce fine particles were found to be a low concentration of the PEG solution, a low precipitator temperature, and low molecular weight of the PEG. The phase behavior of the solution mixture in the saturator presented a qualitative relationship. At the optimized volumetric flow rate ratios, the composition of CO2 in the feed streams was near the bubble points of the saturator temperatures. X-ray and differential scanning calorimetry analyses indicated that LTSAA-treated PEG had a reduced degree of crystallinity, which could be modulated via the precipitator temperature. PEG microparticles prepared by a LTSAA process would be promising carriers for drug-controlled formulations of PEG-drug composite particles.

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Dependence of the structural, the electrical, and the optical properties on the Ar/O2 flow rate ratios for SnO2 thin films grown on p-InSb (111) substrates

Materials Research Bulletin ◽

10.1016/s0025-5408(01)00500-1 ◽

2001 ◽

Vol 36 (1-2) ◽

pp. 349-353 ◽

Cited By ~ 6

Author(s):

T.W. Kim

Keyword(s):

Thin Films ◽

Optical Properties ◽

Flow Rate ◽

Sno2 Thin Films ◽

Rate Ratios

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Thin Oxynitride Films Prepared by Low Pressure Rapid Thermal Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-303-43 ◽

1993 ◽

Vol 303 ◽

Cited By ~ 1

Author(s):

P.K. Mclarty ◽

W.L. Hill ◽

X.L Xu ◽

J.J. Wortman ◽

G.S. Harris

Keyword(s):

Chemical Vapor Deposition ◽

Nitrogen Content ◽

Flow Rate ◽

Vapor Deposition ◽

Chemical Vapor ◽

Low Pressure ◽

Flow Rate Ratio ◽

Thermal Chemical Vapor Deposition ◽

Rate Ratios ◽

Post Deposition

ABSTRACTThin silicon oxynitride (Si-O-N) films have been deposited using low pressure rapid thermal chemical vapor deposition (RTCVD) with silane (SiH4), nitrous oxide (N2O), and ammonia (NH3) as the reactive gases. Structural analysis coupled with a study of deposition conditions indicate that an increase in NH3/N2O flow rate ratios leads to an increased N/O atomic ratio and a decreased Si-O-N deposition rate. Thin film (55-75A) polySi/Si-N-O/Si capacitors and transistors were fabricated for NH3/N2O flow rate ratios from 20% to 100%. Some of the films were subjected to a post deposition anneal at 950°C for 15 seconds in both argon and oxygen. Capacitance voltage measurements indicate a mid-gap interface trap density of ≤ 6 × 1010 eV−1cm−2 for all the films independent of both nitrogen content and post deposition annealing conditions. The transconductance was studied as a function of NH3/N2O flow rate ratio and decreasing peak gm values but improved high field degradation was observed for increased nitrogen content. This is consistent with previous work on nitrided oxides and suggests that the films are under tensile stress. Hot carrier stress at maximum substrate current was performed with the Si-O-N films displaying larger threshold voltage shifts when compared to furnace SiO2 indicating the possible existence of hydrogen related traps.

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Evaluation of Lpcvd Boron Nitride as a Low Dielectric Constant Material

MRS Proceedings ◽

10.1557/proc-427-469 ◽

1996 ◽

Vol 427 ◽

Cited By ~ 1

Author(s):

R. A. Levy ◽

M. Narayan ◽

M. Z. Karim ◽

S. T. Hsu

Keyword(s):

Dielectric Constant ◽

Boron Nitride ◽

Flow Rate ◽

Chemical Properties ◽

Low Dielectric Constant ◽

Processing Conditions ◽

Low Dielectric ◽

Rate Ratios ◽

And Chemical Properties ◽

Deposition Conditions

AbstractThis study characterizes low pressure chemically vapor deposited B-N-C-H as a low dielectric constant material for interlevel dielectric applications. These films are synthesized over a temperature range of 400 to 600 °C and various flow rate ratios using triethylamine borane complex (TEAB) and NH3 as precursors. The dielectric constant of these films exhibit values which varied in the range of 2.6 to 3.5 depending on processing conditions. Low dielectric constant values are achieved at film compositions which approached stoichiometry and have minimal carbon content. The variations in the structural, optical, mechanical, and chemical properties of these films as a function of deposition conditions are also discussed.

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Formation of double emulsion micro-droplets in a microfluidic device using a partially hydrophilic–hydrophobic surface

RSC Advances ◽

10.1039/d1ra06887c ◽

2021 ◽

Vol 11 (56) ◽

pp. 35653-35662

Author(s):

Ampol Kamnerdsook ◽

Ekachai Juntasaro ◽

Numfon Khemthongcharoen ◽

Mayuree Chanasakulniyom ◽

Witsaroot Sripumkhai ◽

...

Keyword(s):

Flow Rate ◽

Frequency Ratio ◽

Encapsulation Efficiency ◽

Double Emulsion ◽

Hydrophobic Surface ◽

Water Droplets ◽

Oil In Water ◽

Rate Ratios ◽

Frequency Ratios ◽

Ratio Range

(a) Droplet encapsulation efficiency & inner and outer diameters of water-in-oil-in-water droplets at various frequency ratios and flow rate ratios and (b) Images of water-in-oil-in-water droplets over a frequency-ratio range of fr = 0.73–1.30

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Acidic Recovery from Wastewater of Automotive Battery Plant Using Membrane Technology

Applied Environmental Research ◽

10.35762/aer.2016.38.1.4 ◽

2016 ◽

pp. 33-41

Author(s):

Nantanee Chaimongkalayon ◽

Sudtida P. Thanasupsin

Keyword(s):

Flow Rate ◽

Rate Ratio ◽

Operating Conditions ◽

Flow Rate Ratio ◽

Anion Exchange Membranes ◽

Recovery Efficiency ◽

Optimum Flow Rate ◽

Rate Ratios ◽

Diffusion Dialysis ◽

Acidic Wastewater

Diffusion dialysis (DD) equipped with anion exchange membranes (AEMs) is used as an effective tool to recover acidfrom various types of waste acid solutions. The aim of this study was to investigate the possibility of using the DD process to recover sulfuric acid (HsSO4) from the acidic wastewater from an automotive battery plant. A numbers of experimental runs was conducted to optimize the equipment’s operating conditions, particularly variations in feed flow and flow rate ratios . The results showed that H2SO4 permeated well through the AEM, while metal ions were efficiently rejected. The recovery of H2SO4 increased as flow rate decreased. Approximately 84.5% of H2SO4 could be recovered at 9 .38 × 10 -5 m3 h-1 m-2. Pb2+ rejection was 69.5%. In addition, recovery efficiency could be improved by increasing the flow rate ratio. At the highest flow rate ratio, DD could recover up to 90% of H2SO4 while the lowest rejection of Pb2+ (61%) was obtained. Also, the investigation of the effect of variation of flow rate ratio on recovery efficiency revealed that the optimum flow rate ratio should be controlled at around 1 to 1.2.

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Microphotometric Characterization of Fluid Segment Populations Generated in Different Simple Microfluidic Networks

ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B ◽

10.1115/icnmm2006-96172 ◽

2006 ◽

Author(s):

J. M. Ko¨hler ◽

P. A. Groß

Keyword(s):

Flow Rate ◽

Free Fluid ◽

Flow Conditions ◽

Carrier Liquid ◽

Fluid Network ◽

On Line ◽

Deformation Stress ◽

The Stability ◽

Rate Ratios

The stability of fluid segments is limited by deformation stress and by coalescence events. Both factors are typical for the passage of fluid segments through micro fluidic networks. Therefore, the coalescence behaviour of micro fluid segments in simple net work structures in dependence of flow rate ratios was investigated and characterized by the composition of obtained segment populations. Series of segments of different size and distance were generated either in a double T- or in a triple T-arrangement. PTFE elements were used for the micro fluid network. Nearly pulsation-free fluid actuation was realized by syringe pumps. The flow conditions in the input streams of carrier liquid and injected solutions remained constant during the experiments. Segment sequences become divers by different injection, stacking and coalescence events. The resulting segment sequences were characterized by on-line micro photometry. The populations of obtained micro fluid segments during each experiment were characterized by the distribution of segment size and segment distance or segment periode, respectively. Simulations support the assumption, that the character of segment populations is mainly determined by the flow rate ratios and by the coalescence sensitivity beside the topology of the fluidic network.

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Microscale Laser-Induced Fluorescence Method for Non-Intrusive Temperature Measurement

Volume 11: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2007-41935 ◽

2007 ◽

Author(s):

Pramod Chamarthy ◽

Steven T. Wereley ◽

Suresh V. Garimella

Keyword(s):

Flow Rate ◽

Rhodamine B ◽

Calibration Curve ◽

Laser Induced Fluorescence ◽

Normalization Procedure ◽

Fluid Stream ◽

Temperature Dependent ◽

Different Temperatures ◽

Rate Ratios ◽

Temperature Responses

Ratiometric Laser Induced Fluorescence (LIF) Thermometry is applied for temperature measurements in a ‘T’ junction, using microscale visualization methods. Rhodamine B (RhB) and Rhodamine 110 (Rh110) are used as the temperature-dependent and temperature-independent dye, respectively. The temperature responses of the two dyes were carefully measured for different concentrations. A novel normalization procedure for the calibration curve is proposed to render the technique system-independent. The mixing plane between a hot and a cold fluid stream for three different temperatures and three different flow rate ratios is visualized using 4X and 10X magnifications.

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