New Dispersed Phase of Electrorheological Fluids:TiO_2 Coating Graphite Particles

We have prepared novel coated particles, with a conductor graphite core and a dielectric TiO2 coating, as the dispersed phase of electrorheological fluids. One order of magnitude enhancement in the shear stress is obtained by using such composite particles, when it is compared with that of TiO2 particles. The experimental results show a way to get excellent ER system.

EFFECT OF DISPERSED PHASE PARTICLES ON ELECTRICAL CONDUCTION OF PEO-NaSCN

Fast ionic conductors are one kind of solid state material with ionic conductivity as high as that of melten salts or liquid electrolytes.Ionic conductivity is one of the important parameters for characterizing a fast ionic conductor.For a long time materialists and chemists have made great efforts in search of new fast ionic conductors with high ionic conductivity.In view of structure,they have synthesised silver and copper fast ionic conductors with so called open structures.But it is not so successful for searching more applicable alkaline fast ionic conductors.Since polymer has flexibility for making thin film,it concentrates attention on the polymer-alkaline salt complex.Fenton et al.have first reported poly(ethylene oxide) (PEO)-alkaline salt complex.Later on Armard et al.have investigated the electrical property of PEO-NaSCN.

Property and Activity of Molybdates Dispersed on Silica Obtained from Various Synthetic Procedures

The synthesis and characterization of several dispersed molybdena catalysts on silica support (MoO3-SiO2) prepared from a variety of precursors (Mo(VI)-acetylacetonate, oxo-peroxo Mo-species, hydrated ammonium heptamolybdate) and preparation methods (deposition of the Mo-phase on finite SiO2 support by aqueous and methanol impregnations, by adsorption, by oxo-peroxo route-like, and by one-step synthesis of MoO3-SiO2 system with molecular precursors) are presented. The molybdena concentration on silica was comprised in a large interval (1.5 - 14 wt%) depending on the preparation method which governed the Mo-loading on silica. Convenient comparisons among samples at similar Mo-concentration have been made discussing the morphologic-structural (XRD, XPS, UV-vis-DRS, and N2-adsorption) and physicochemical (TG-DTG, TPR, and n-butylamine-TPD) sample properties. Polymeric octahedral polymolybdate aggregates predominated in the samples prepared by aqueous and methanol impregnations, which were at high Mo-concentration. On the contrary, isolated Mo(VI) species in distorted Td symmetry predominated in the sample prepared by adsorption which was at very low Mo-concentration. The sample acidity was composed of a weak acidy site population, associated with the silica support, and a strong acid site population associated with the Mo-dispersed phase. Oxidation tests of formaldehyde, an oxygen-containing VOC (Volatile Organic Compound), were performed to determine the prevalent redox or acidic function of the Mo-species at the surface of the catalysts.

Phase dispersion of Raman and Rayleigh-enhanced four-wave mixings in femtosecond polarization beats

Based on color-locking noisy field correlation in three Markovian stochastic models, phase dispersions of the Raman- and Rayleigh-enhanced four-wave mixing （FWM） have been investigated. The phase dispersions are modified by both linewidth and time delay for negative time delay, but only by linewidth for positive time delay. Moreover, the results under narrowband condition are close to the nonmodified nonlinear dispersion and absorption of the material. Homodyne and heterodyne detections of the Raman, the Rayleigh and the mixing femtosecond difference-frequency polarization beats have also been investigated, separately.

Determination of Tebuconazole Residue in Apples and Vegetables by Matrix Solid Phase Dispersion-Gas Chromatography

[ Objective] The study aimed to determine tebuconazole residue in apples and vegetables using matrix solid phase dispersion-gas chro- matography （MSPD-GC）. [ Method] The effects of extraction and determination conditions on the detection of tebuconazole left in apples and veg- etables were analyzed, and the optimum extraction conditions were determined. [ Result] The recovery rate of tebucenazole was the highest when the ratio of a sample to florisil dispersant was 1 ： 4, and the mixture of hexane and acetone （ 1 ： 1 ） with total volume of 8 ml was as the eluant. Under the optimum conditions, the relative standard deviation （RSD） of the method was 4.9% -7.6%, and the detection limit was 0.1 tJg/g, while the re- covery rate of tebuconazole changed from 86.7% to 95. 2% . [ Conclusion] The method was simple, accurate, sensitive and applicable to the de- termination of tebuconazole in aaricultural Droducts.

Determination of seven active components in Salvia miltiorrhiza herb by matrix solid phase dispersion combined with ion liquid extraction followed by high performance liquid chromatography

A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet detection(UV)is proposed,and it was applied to determine the seven active compounds in Salvia Miltiorrhiza herb.SGSIL and ionic liquid[BMIM]BF4 were used as the adsorbent and the green elution reagent in the MSPD procedure.Several extraction conditions including type of filler and elution solvent,the volume of elution solvent,material liquid ratio were optimized.Under the optimum conditions,the SGSIL-MSPD-HPLC method showed a low limit of detection(LOD,S/N=3)of 0.0122-0.8788μg/mL for standard solution,limit of quantification(LOQ,S/N=10)of 0.0406-2.9292μg/mL for standard solution,wide linear range from 1.56 to 2000μg/mL for all compounds for standard solution,correlation coefficients(r)of more than 0.9990,acceptable reproducibility(relative standard deviations,RSDs<3.54%),and precision of RSDs<3.36%for intra-day,RSDs<3.50%for inter-day.The satisfactory recoveries ranged from 96.4 to 102.5,with RSDs less than 3.45%.The developed SGSIL-MSPD method is easier and more suitable for the determination of the seven active compounds in Salvia Miltiorrhiza herb than the traditional ultrasonic extraction.It was an effective and efficient method for the extraction and quantification of the seven active compounds in traditional Chinese herbal samples.

Joint Angle Correction in Rheumatoid Arthritis and Its Reliability Analysis Based on Phase Dispersion Quantification

Background: Rheumatoid arthritis is a form of autoimmune disease characterized by synovitis that can ultimately cause joint deformities and impaired functioning. The cartilage destruction is one of the most important indicators for diagnosis and treatment of rheumatoid arthritis, and it is radiographically manifested as joint space narrowing. Issue: In the literature, the joint space narrowing progression between a baseline and its follow-up finger joint images can be quantified by using image registration algorithm. We found that the inconsistencies of joint angles may lead to characteristic mismatches and thus severely affect the accuracy of joint space narrowing quantifications. Methods: In this work, we introduce a rotation invariant phase only correlation in joint space narrowing quantification for the joint angle correction. Further, we propose a confidence index to quantify the quantification reliability of phase only correlation based on phase dispersion in phase difference spectrum. Conclusion: In our clinical experiments, the proposed quantification method can effectively overcome and manage the mismatch due to the inconsistency of joint angles. Additionally, the confidence index shows a high consistency with the joint space narrowing progression examinations manually done by a trained radiologist and one radiological technologist.

Dynamic Mechanical Behavior and Prediction for PP/POE Blends

Polypropylene（PP）/ethylene-octene copolymer（POE） blends were prepared with a twin-screw extruder.Their dynamic mechanical behavior were systematically investigated.The results show that PP/POE blends are heterogeneities with a partial compatible two-phase structure,the glass transition temperature of PP phases in the blends tends to shift towards high temperature with increasing the POE content,and the glass transition temperature of POE phases shifts towards the low temperature with increasing the PP content.The Kerner＇s dispersed phase model and co-continuous phase model can reasonably predict the visco-elasticity of PP/POE blends with different compositions.Additionally,the morphological structure of the blends can be estimated via comparing the predicted DMA behavior with the experimental data.

Symplectic analysis for elastic wave propagation in two-dimensional cellular structures

On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.

Tb(III) Transport in Dispersion Supported Liquid Membrane System with D2EHPA as Carrier in Kerosene

The transport of Tb（III） in dispersion supported liquid membrane（DSLM） with polyvinylidene fluoride membrane（PVDF） as the support and dispersion solution including HCl solution as the stripping solution and di（2-ethylhexyl） phosphoric acid（D2EHPA） dissolved in kerosene as the membrane solution, has been studied. The effects of pH value, initial concentration of Tb（III） and different ionic strength in the feed phase, volume ratio of membrane solution to stripping solution, concentration of HCl solution, concentration of carrier, different stripping agents in the dispersion phase on the transport of Tb（III） have also been investigated, respectively. As a result, the optimum transport conditions of Tb（III） were obtained, i.e., the concentration of HCl solution was 4.0 mol/L, the concentration of D2EHPA was 0.16 mol/L, the volume ratio of membrane solution to stripping solution was 30：30 in the dispersion phase and pH value was 4.5 in the feed phase. Ionic strength had no obvious effect on the transport of Tb（III）. Under the optimum conditions, the transport percentage of Tb（III） was up to 96.1% in a transport time of 35 min when the initial concentration of Tb（IIl） was 1.0× 10 -4 mol/L. The diffusion coefficient of Tb（III） in the membrane and the thickness of diffusion layer between feed phase and membrane phase were obtained and the values were 1.82×10 -8 m2/s and 5.61 um, respectively. The calculated results were in good agreement with the literature data.

Accurate and sensitive determination of hydroxychloroquine sulfate used on COVID-19 patients in human urine,serum and saliva samples by GC-MS

A rapid,accurate,and sensitive analytical method,ultrasonication-assisted spraying based fine droplet formationeliquid phase microextractionegas chromatographyemass spectrometry(UA-SFDF-LPME-GCMS),was proposed for the determination of trace amounts of hydroxychloroquine sulfate in human serum,urine,and saliva samples.To determine the best extraction strategy,several liquid and solid phase extraction methods were investigated for their efficiencies in isolation and preconcentration of hydroxychloroquine sulfate from biological matrices.The UA-SFDF-LPME method was determined to be the best extraction method as it was operationally simple and provided accurate results.Variables such as the extraction solvent,spraying number,sodium hydroxide concentration and volume,sample volume,mixing method,and mixing period were optimized for the proposed method using the onevariable-at-a-time approach.In addition,Tukey’s method based on a post hoc comparison test was employed to evaluate the significant difference between the parameters inspected.After the optimization studies,the limit of detection(LOD)and limit of quantification(LOQ)were determined to be 0.7 and 2.4 mg/kg,respectively.The sensitivity of the GC-MS system based on the LOD was enhanced approximately 440-fold when the UA-SFDF-LPME method was employed.Spiking experiments were also conducted for the human serum,urine,and saliva samples to determine the applicability and accuracy of the proposed method.Recoveries for the human serum,urine,and saliva samples were found to be in the ranges of 93.9%-101.7%,95.2%-105.0%,and 93.1%-102.3%,respectively.These results were satisfactory and indicated that the hydroxychloroquine sulfate level in the above biological samples could be analyzed using the proposed method.

Synthesis of a Novel Imidazole Ionic Liquid Modified Mesoporous Silica SBA15 for Selective Separation and Determination of Inorganic Arsenic in Rice

A novel 1-methylimidazole ionic liquid modified SBA15 mesoporous silica(1-MIIL@SBA15) was synthesized and applied to selective separation of inorganic arsenic(iAs) in rice by dispersive solid phase extraction(DSPE), followed by hydride generation-atomic fluorescence spectrometric(HG-AFS) quantification. The prepared sorbent was characterized by FTIR, FESEM, BET and Zeta potential. Key parameters of adsorption and desorption in DSPE were optimized using standard reference material 1568 b rice flour. Under optimal conditions, the limit of detection was 8.776 ng/kg, relative standard deviation was ≤2.0%, and recoveries of iAs were in the 92.3～94.4% range. This method was successfully applied to the determination of iAs in rice. Under acidic condition, the electrostatic interaction between the positively charged 1-MIIL@SBA15 and anionic iAs played an important role in selective iAs separation, rendering this method suitable for iAs analysis.

LIQUID PHASE FLOW ESTIMATION IN GAS-LIQUID TWO-PHASE FLOW USING INVERSE ANALYSIS AND PARTICLE TRACKING VELOCIMETRY

An inverse analysis algorithm is proposed for estimating liquid phase flowfield from measurement data of bubble motion. This kind of technology will be applied in future forvarious estimation of fluid flow in rivers, lakes, sea surface flow, and also microscopic channelflow as the problem-handling in civil, mechanical, electronic, and chemical engineering. Therelationship between the dispersion motion and the carrier phase flow is governed and expressed bythe trans-lational motion equation of spherical dispersion. The equation consists of all the forcecomponents including inertia, added inertia, drag, lift, pressure gradient force and gravity force.Using this equation enables us to estimate the carrier phase flow structure using only the data ofthe dispersion motioa Whole field liquid flow structure is also estimated using spatial or temporalinterpolation method. In order to verify this principle, the Taylor-Green vortex flow, and theKarman vortex shedding from a square cylinder have been chosea The results show that the combinationof the inverse analysis and Particle Tracking Velocimetry (PTV) with the spatio-temporalpostprocessing algorithm could reconstruct well the carrier phase flow of the gas-liquid two-phaseflow.

Effects of Composition on Microstructure and Crystallization Behavior for Impact Polypropylene Copolymer Investigated by Restructuring the Complex Core-Shell Dispersed Particles in Ternary Blends

A series of ternary blends of polypropylene/ethylene-propylene random copolymer/ethylene-propylene segmented copolymer（HPP/EPR/Eb P） whose microstructures are similar to those of impact polypropylene copolymer（IPC） were prepared in order to systematically investigate the effects of composition on microstructure and crystallization behavior of IPC. The observation of primary phase morphology reveals that the dispersed phase with core-shell structure could be rebuilt in certain composition and excessive EPR leads to a bicontinuous phase structure in ternary blends. After undergoing same quiescent crystallization including isothermal and non-isothermal crystallization, these blend samples exhibit special composition-dependent melting behavior, i.e., the melting point increases markedly with the increase of EPR content until it turns down at a critical content（about 30 wt%）. The crystallization behavior is mainly ascribed to the different nucleation abilities. It is suggested that although the compatibility between EPR and HPP components becomes worse with the increase of EPR content due to the increased interfacial area and the decreased concentration of Eb P, higher EPR content in the blend facilitates to heterogeneous nucleation except for the appearance of obvious bicontinuous phase structure.

Trace determination of hexabromocyclododecane diastereomers in water samples with temperature controlled ionic liquid dispersive liquid phase microextraction

A novel temperature controlled ionic liquid dispersive liquid phase microextracfion （TCIL-DLPME） coupled with rapid resolution liquid chromatography-electrospray tandem mass spectrometry （RRLC-ESI-MS-MS） has been developed for the enrichment and determination of three hexabromocyclododecane diastereomers （HBCDs） in water samples. Green solvent ionic liquid （IL） was used as extraction solvent instead of toxic organic solvents. This technique also avoided the usage of dispersive solvent. Some important parameters that might affect the extraction efficiency were optimized. Under the optimum conditions, good linear relationship, sensitivity and reproducibility were obtained. All the limits of detection for the three diastereomers were 0.1 ng/ mL. The linear range was obtained in the range of 1-100 ng/mL for the total amount of three HBCD diastereomers. It was satisfactory to analyze real environmental water samples with the recoveries ranging from 77.2% to 99.3%. The main advantage of the method is toxic organic solvent-free.

Mathematical Modeling of Multi-sized Argon Gas Bubbles Motion and Its Impact on Melt Flow in Continuous Casting Mold of Steel

The 3D turbulence k-ε model flow of the steel melt （continuous phase） and the trajectories of individual gas bubbles （dispersed phase） in a continuous casting mold were simulated using an Eulerian-Lagrangian approach. In order to investigate the effect of bubble size distribution, the radii of bubbles are set with an initial value of 0. 1- 2.5 mm which follows the normal distribution. The presented results indicate that, in the submerged entry nozzle （SEN）, the distribution of void fraction is only near the wall. Due to the fact that the bubbles motion is only limited to the wall, the deoxidization products have no access to contacting the wall, which prevents clogging. In the mold, the bubbles with a radius of 0. 25--2.5 mm will move to the top surface. Larger bubbles issuing out of the ports will attack the menis- cus and induce the fluid flows upwards in the top surface near the nozzle. It may induce mold powder entrapment into the mold. The bubbles with a radius of 0.1--0.25 mm will move to the zone near the narrow surface and the wide surface. These small bubbles will probably be trapped by the solidification front. Most of the bubbles moving to the narrow surface will flow with the ascending flow, while others will flow with the descending flow.

Synergetic migration behavior of La and Ce and related microstructure character of Cr-V-RE co-doped WC-Co alloy

The as-sintered sinter skin and the polished section of WC-11Co-0.4Cr 3 C 2-0.3VC-0.2RE（RE=mischmetal with La/Ce ratio of 0.65） alloy were analyzed.It was shown that the microstructures on the skin and in the inner part of the alloy were all characterized with a WC＋β＋M structure,where β was a cobalt-based binder phase and M represented a RE-containing phase.There existed an inward diffusion of S atoms,which caught and fixed the Ce atoms in the alloy and an outward diffusion of La atoms during the sintering process.Consequently,the M phase was characterized with the decreased La/Ce ratio（0.59） in the inner part and the increased La/Ce ratio（1.01） on the skin.The M phase on the skin was characterized with a γ-Ce 2 S 3 type structure.To suppress the long range migration of rare earth to the skin,S in the sintering atmosphere had to be eliminated.

Separation of Eu(Ⅲ) with supported dispersion liquid membrane system containing D2EHPA as carrier and HNO_3 solution as stripping solution

The Eu（III） separation in supported dispersion liquid membrane （SDLM）, with polyvinylidene fluoride membrane （PVDF） as the support and dispersion solution containing HNO3 solution as the stripping solution and Di（2-ethylhexyl） phosphoric acid （D2EHPA） dis- solved in kerosene as the membrane solution, was studied. The effects ofpH value, initial concentration of Eu（III） and different ionic strengths in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HNO3 solution, concentration of carrier, different stripping agents in the dispersion phase on the separation of Eu（III） were also investigated, respectively. As a result, the optimum separation conditions of Eu（III） were obtained as the concentration of HNO3 solution was 4.00 mol/L, concentration of D2EHPA was 0.160 mol/L, and volume ratio of membrane solution to stripping solution was 30：30 in the dispersion phase, and pH value was 5.00 in the feed phase. Ionic strength had no obvious effect on the separation of Eu（III）. Under the optimum conditions studied, when initial concentration of Eu（III） was 1.00× 10^-4 mol/L, the separation rate of Eu（III） was up to 94.2% during the separation period of 35 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The results were in good agreement with the literature data.

Modeling of Ce（IV） transport through a dispersion flat combined liquid membrane with carrier P507

A mathematical model for the transport of Ce （IV） from hydrochloric acid solutions through dispersion flat combined liquid membrane （DFCLM） with contain 2- ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （P507） as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick＇s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce（IV） and the carrier to take place only at the solvent-aqueous interfaces. Model concentration profiles are obtained for the Ce（IV）, from which extraction velocities are predicted. The experimental and simulated Ce（IV） extractions showed similar tendencies for a high Ce （IV） concentration and acidity case.The model results indicate that high initial Ce（IV） concentrations and acidity both have detrimental effects on Ce（IV） extraction and stripping. The diffusion coefficient of Ce（IV） in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10-8m2·s-1 and 31.2 μm, respectively. The results are in good agreement with experimental results.

Separation of Trivalent Samarium through Facilitated Stripping Dispersion Hollow Fiber Liquid Membrane Using p204 as Mobile Carrier

The separation of Sm（III） through stripping dispersion hollow fiber liquid membrane system （SDHFLM） containing feed phase adding acetate buffer solution and dispersion solution with HC1 solution as the stripping solution and membrane solution of di（2-ethylhexyl） phosphoric acid （p204） dissolved in kerosene, has been studied. A set of factors were studied, including pH value, initial concentration of Sm（III） and different ionic strength of feed phase, volume ratio of membrane solution and stripping solution （O/W）, HC1 concentration, carrier concentration, different stripping agents of dispersion phase on Sm（III） separation. Experimental results indicate that the optimum separa- tion conditions of Sm（III） were obtained as that HC1 concentration was 4.00 tool/L, p204 concentration was 0.150 mol/L, and volume ratio of membrane solution and stripping solution （O/W） was 1.00 in the dispersion phase, and pH value was 4.60 in the feed phase. Ionic strength had no obvious effect on separation of Sm（III）. When initial Sm（III） concentration was 1.00 × 10^-4 mol/L, the separation rate of Sm（III） was up to 93.5% in 85 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The modeled results were in good agreement with the experiment data.