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“Relay-mode”promoting permeation of water-based fire extinguishing agent in granular materials porous media stacks

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Chinese Journal of Chemical Engineering 2022年第7期35卷 98-112页

作者： Kang Wang Wei Tan Liyan Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300350China

Water-based fire extinguishing agent is the main means to deal with smoldering fires.However,due to the hydrophobic properties of the particle surface,the porous medium channel provide resistance and slow down the extinguishing agent flow during the downward permeation process.To promote the liquid permeation process in such porous media,this work studied liquid imbibition process and analyzed the oscillating and attenuating process of liquid level in capillary channel by theoretical,experimental,and numerical methods.An empirical mathematical equation was proposed to describe the oscillating process,and the effects of the capillary diameter and contact angle parameters on the transportation process were analyzed.Based on this,the“relay-mode”was proposed to promote the liquid transportation forward.Finally,the transient simulation results of liquid permeation in coal stacks showed when the liquid flowed through the channel with changed diameter from large to small ones,the transportation distance was several times longer than that through the unidiameter ones.The trend of liquid“relay-mode”in capillaries can be used to promote the permeation in granular materials porous media stacks.The relevant results also provide new thoughts to develop the water-based fire extinguishing agents and then improve the firefighting efficiency of deep-seated fire in porous media stacks.

关键词： Granular materials Porous media Safety permeation Water-based fire extinguishing agent

permeation fill-tube design for inertial confinementfusion target capsules

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High Power Laser Science and Engineering 2017年第1期5卷 34-40页

作者： B.S.Rice J.Ulreich C.Fella J.Crippen P.Fitzsimmons A.Nikroo Rochester Institute of Technology 78 Lomb Memorial DriveRochesterNY 14623-5604USA Laboratory for Laser Energetics University of Rochester250 East River RoadRochesterNY 14623-1299USA General Atomics San DiegoCA 92186USA Lawrence Livermore National Laboratory LivermoreCA 94550USA

A unique approach for permeation filling of nonpermeable inertial confinement fusion target capsules with deuterium–tritium(DT) is presented. This process uses a permeable capsule coupled into the final target capsule with a 0.03-mmdiameter fill tube. Leak free permeation filling of glow-discharge polymerization(GDP) targets using this method have been successfully demonstrated, as well as ice layering of the target, yielding an inner ice surface roughness of 1-μm rms(root mean square). Finally, the measured DT ice-thickness profile for this experiment was used to validate a thermal model's prediction of the same thickness profile.

关键词： fill-tube inertial confinement fusion permeation fill target capsule

Effect of plasma surface treatment of poly(dimethylsiloxane) on the permeation of pharmaceutical compounds

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药物分析学报：英文版 2017年第5期7卷 338-342页

作者： Laura J.Waters Catherine V.Finch A.K.M.Mehedi H.Bhuiyan Karl Hemming John C.Mitchell Department of Pharmacy School of Applied Science University of Huddersfield Medway Centre for Pharmaceutical Sciences University of Greenwich

This paper addresses the modification of poly(dimethylsiloxane), i.e. PDMS, using plasma surface treatment and a novel application of the membrane created. A set of model compounds were analysed to determine their permeation through PDMS, both with and without plasma treatment. It was found that plasma treatment reduced permeation for the majority of compounds but had little effect on some compounds, such as caffeine,with results indicating that polarity plays an important role in permeation, as is seen in human skin. Most importantly, a direct correlation was observed between plasma-modified permeation data and literature data through calculation of membrane permeability(K_p) values suggesting plasma-modified silicone membrane(PMSM) could be considered as a suitable in vivo replacement to predict clinical skin permeation.

关键词： permeation PDMS Silicone Plasma Flux Hydrophobicity

Molecular weight determination of a newly synthesized guanidinylated disulfide-containing poly(amido amine) by gel permeation chromatography

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Asian Journal of Pharmaceutical Sciences 2017年第3期12卷 292-298页

作者： Haonan Xing Mei Lu Lei Xian Jinmin Zhang Tianzhi Yang Li Yang Pingtian Ding School of Pharmacy Shenyang Pharmaceutical UniversityShenyangChina Department of Basic Pharmaceutical Sciences School of PharmacyHusson UniversityBangorMEUSA

A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa.

关键词： Guanidinylated disulfide-containing poly(amido amine) Synthesis Cationic gene delivery vector Molecular weight determination Gel permeation chromatography

MECHANISM　OF　Re-B-V　CO-permeation

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中国有色金属学会会刊：英文版 1997年第1期7卷 92-96页

作者： Li, Fengzhen Liu, Zhaojing Jin, Quan Xu, Zhihui Harbin Univ of Science & Technology Harbin China

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关键词： Re B V co permeation mechanism kinetics rare earth pasty agent

Relationship between the permeation-Diffusion Parameters of a Single-File Channel

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Chinese Physics Letters 2012年第1期29卷 41-44页

作者：刘健樊建芬 College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123 Shanghai Institute of Applied Physics Chinese Academy of SciencesPO Box 800-204Shanghai 201800

Two sets of widely used parameters can describe the molecular permeation through a nanochannel.One is permeation rate j and its diffusion Dn,and the other is flow and net flux.We establish a relationship between the two sets for a single-file nenochannel,as well as its dependence on the temperature and pressure difference between the two ends of a single-file channel,based on the Brownian motion theories and verified with molecular dynamics simulations for the water diffusion in a transmembrane (6,6) armchair carbon nanotube.Simulation results are in excellent agreement with our predictions.

关键词： permeation diffusion Brownian

Influence of permeation effect on themicrofabric of the slip zone soils: A case study from the Huangtupolandslide

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Journal of Mountain Science 2019年第6期16卷 1231-1243页

作者： MIAO Fa-sheng WU Yi-ping XIE Yuan-hua LI Lin-wei LI Jie HUANG Lei Faculty of Engineering China University of GeosciencesWuhan 430074China China University of Geosciences Press Wuhan 430074China

This study aims to investigate the correlation between the permeation effect and microfabric of the slip zone soils with Huangtupo landslide in the Three Gorges Reservoir as the study case. Based on the permeability test and scanning electron microscope(SEM) images analysis, the fractal theory and probability entropy are used to quantify the characteristics of the remodeling specimens. First, the relationships between initial moisture content(IMC) and microstructure of the soil(percentage of particle area(PPA), pore roundness(Rp)) before and after permeability test are summarized. Then, the fractal dimension of the soil(pore distribution(Dpd), pore size(Dps)) are analyzed under the permeation effect. Based on the probability entropy, the entropy of pore(Ep) is used to characterize the porosity orientation, and the rose diagrams are used to show the particle orientation under the permeation effect. Finally, the relationship between the microstructure of the soil and its mechanical property is discussed. Results show that under the permeation effect, the microstructure of the soil has undergone tremendous changes. A flat long pore channel is formed. The order of the pore arrangement is enhanced, and soil particles switch the long axis to parallel infiltration direction to reach a new steady state. It can be inferred that the strength of soil would be weakened if the fractal dimension of soil pore decreases under any external environment.

关键词： permeation effect Slip zone soils Microstructure SEM Fractal theory Preferential orientations

Kinetics of Local Anesthetic Interactions with Model Membranes: Adsorption and permeation

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Open Journal of Anesthesiology 2022年第1期12卷 55-75页

作者： Gary Strichartz Pain Research Center Department of Anesthesiology Perioperative and Pain Medicine Brigham & Women’s Hospital Harvard Medical School Boston MA USA

Introduction: Local anesthetics (LAs) must be adsorbed to and permeate through membranes to reach their sites of action. The rates of these processes critically affect drug actions at the cellular level and also the in vivo pharmacokinetics of perineurally injected drugs. Therefore, we measured the adsorption equilibria and permeation kinetics of two LAs local anesthetics with markedly different hydrophobicities: tetracaine (TTC, Poctanol:buffer = 3.6 × 103) and procaine (PRO, Poctanol:buffer = 8.1 × 101), in unilamellar membranes of different composition and fluidity. Methods: Interactions with unilamellar vesicles made of dipalmitoylphosphatidylcholine (DPPC), at 23°C (solid gel state) or 45°C (liquid crystal state), without or with cholesterol (Chol), were investigated by a combination of fluorescence and stopped-flow techniques. Membrane adsorption was monitored by the LA’s fluorescence. Membrane permeation was monitored by the decrease of fluorescence intensity of intra-vesicular pyranine, when quenched by neighboring TTC or PRO. Results: Ionized TTC (TTCH+) and procaine (PROH+) adsorb to membranes more slowly and weakly than their neutral counterparts (time constant τ ~ 0.1 sec). Fluidizing of membranes, at the higher temperature (45°C) or by Chol inclusion, accelerated LA adsorption (faster than the mixing time of the stopped-flow device, 0.008 s). permeation of protonated TTCH+ through the solid gel DPPC membranes (23°C) occurred far more slowly than adsorption, (τ = 36.7 ± 0.7 s, n = 9), and 3 times slower than neutral TTC (τ = 10.9 ± 0.7 s, n = 9);neutral PRO permeated these membranes at the same rate as TTC. Inclusion of Chol with DPPC, disordering the fatty acyl tails of membrane phospholipids while crowding their polar headgroups, slowed permeation of TTC and of PRO to an even greater degree. Conclusions: Local anesthetic permeation through membranes is limited by the t

关键词： Local Anesthetic Fluorescence Phospholipids Kinetics Stop-Flow Technique Adsorption permeation

Influence of fatty acids in edible oils on lutein micellization and permeation in a simulated digestion model

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Food Bioscience 2022年第2期46卷 231-240页

作者： Ishani Bhat Vallikannan Baskaran Bangera Sheshappa Mamatha Nitte(Deemed to be University) Nitte University Center for Science Education and Research(NUCSER)Paneer CampusDeralakatteMangaluru575018KarnatakaIndia Department of Biochemistry and Nutrition CSIR-Central Food Technological Research InstituteMysore570020KarnatakaIndia

Lutein is a nutraceutical compound that promotes human eye health and prevents neurodegenerative diseases.The oral bioavailability of lutein is affected by both extrinsic and intrinsic factors in the host.Although hydrophobicity of the compound is further challenging,its lipophilicity can be utilized to micellize and thereby improve its oral bioavailability.Currently,available data on the effects of dietary fats on lutein micellization and permeation is limited and needs further exploration.In this study,the influence of 17 carrier type edible oils on lutein micellization and permeation,was investigated in a simulated digestion model.The overall effectiveness of these oils to permeate micellized lutein was attributed to its Fatty Acid(FA)profile.While 94%of the edible oils exhibited a positive influence on the permeation of micellized lutein,the micellization and permeation efficiency of these oils were significantly(p≤0.05)modulated by the saturation of FA in the order Saturated(SFA)>Mono-Unsaturated(MUFA)>Poly-Unsaturated(PUFA).The highest apparent permeability coefficient was exhibited by lutein micellized in ghee(3.01×10^(-6) cm/s)and butter(2.93×10^(-6) cm/s),which was 1.28 and 1.24 folds higher than lutein alone(2.35×10^(-6) cm/s)respectively.Exceptionally MUFA rich olive oil and PUFA rich flaxseed oil improved lutein permeation by 1.19(2.80×10^(-6) cm/s)and 1.14 folds(2.69×10^(-6) cm/s)respectively.This study is the first to report the influence of saturated fatty acids on micellization and permeation of lutein.Furthermore,the outcomes of this study offer the field of lutein delivery systems a fresh perspective.

关键词： Lutein Nutraceutical Dietary lipids Micellization permeation Simulated digestion model