Kinds Of Liquids Research Articles

Quantification of polyethylene wax in semibatch laboratory reactor and a study of different parameters on wax production as a by‐product in the slurry ethylene polymerization

AbstractIn coordination polymerization of alpha‐olefins utilizing Ziegler‐Natta catalysts via slurry, polyolefin is produced with other by‐products such as polyethylene wax. Wax is defined as a linear short chain saturated by hydrocarbons in the relevant industries. Hexane and heptane are two of the most common suspending agents for the slurry process and wax molecules are soluble or swollen in these kinds of liquids. After termination of polymerization, wax separates from the main product by physical processes. A procedure for wax quantification in a laboratory reactor is suggested. Also, impacts of various factors such as reaction duration, pressure, and cocatalyst on wax generation have been investigated. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Experimental investigation of liquid disintegration by rotary cups

The disintegration of liquid by rotary cups has been investigated experimentally. The mechanism of direct drop formation and ligament formation in a rotary cup was studied using photos taken by a high-speed camera. Two kinds of liquids and three kinds of cups were used in the experiment. In the study, we found that three different types of disintegration formation occur as the angular speed increases in a given flow rate. The equations have been derived theoretically for calculating diameter of liquid drop produced by direct drop formation and ligament formation and the dimensionless equations obtained from the experimental results are applicable for calculating diameter of drops in a wide range of operating conditions. In the process of disintegration by ligament formation, the diameter of liquid drop is determined by the diameter of tail end of ligament, which was constant in diameter. The transition equations from direct drop formation to ligament formation and ligament formation to sheet formation arranged by three dimensionless parameters and compared with various experimental results. The transition equations fit quite well in the trend shown by the experimental date and they are applicable in a particular range of We, i.e. 103<We<105.

Investigation on color variation of Morpho butterfly wings hierarchical structure based on PCA

Morpho butterfly wings show brilliant blue color, which has a close relationship with the hierarchical micro/nano structures on the surface of scales. When liquids such as methanol, ethanol and isopropanol with different refractive indexes drop onto the scales, the reflectance of wings would decrease. The main peaks of reflectance shift to the right and the scales turn to yellow-green. After the liquids volatilizes completely, the scales revert to the original blue color. The typical micro/nano structures of Morpho butterfly wing scales are modeled, and the reflectance variation in the course of dropping liquids is simulated. Furthermore, the principal component analysis (PCA) method is employed to analyze the experimental and simulation reflectance data, extract principal components and reduce dimensions. As a result, the curves mapping the reflectance variation are clearly shown in the coordinate system consisting of three principal components. The typical color variation of scales during the dropping process could be monitored, and different kinds of liquids could be obviously distinguished according to the distributed regions of mapping points. This study provides guidance to environmental media detecting as well as data processing, and enhances the fabrication and application of the mimic Morpho butterfly wings micro/nano structures.

Oscillations of a Hanging Liquid Drop, Driven by Interfacial Dielectric Force

Abstract Experimental technique is proposed to excite oscillations of a hanging liquid droplet by applying interfacial dielectric force directly upon the droplet surface. The force proved to be applicable for all kinds of liquids and solutions including non-conductive, isolating liquids. The oscillations are detected optically, with the help of a laser beam. The measured resonant frequency modes and resonance half-widths may be used to retrieve information about the surface properties of the droplet (surface tension and surface charge, in particular). The method is applicable to a wide variety of liquids and interfaces. Possible applications are analyzed and discussed.

The Design of LDF Data Acquisition System Based on LabVIEW

In the formation of liquid drops, different kinds of liquids may have different outer profiles; the change of volume and shape in the process of drop formation can indirectly reflect liquid's physical and chemical properties, such as surface tension and viscosity, etc. Real-time detection the size of drops in the forming process is on the basis of drop analysis technique. Previous researchers have studied that optic fiber and capacitance drop sensor fusion technology can indirectly gain drop's form and the volume. This article is based on the optic fiber and capacitance drop sensor theory, designing the system based on the LabVIEW software to realize the LDF (Liquid Drop Fingerprint) data acquisition function. The experiment results show that the system can well realize the acquisition, compared with the traditional VC programming technology, this data acquisition system is high efficiency.

Tuberculous pleurisy: High adenosine deaminase level in cold abscess content

Introduction: Tuberculous pleurisy is one of the most common form of extrapulmonary tuberculosis (TB). Measurement of adenosine deaminase (ADA) level in the effusions is advocated to have a high diagnostic yield in the diagnosis of tuberculous pleurisy as well as pericardial and peritoneal effusions due to TB. The diagnostic yield of ADA measurement in other materials such as abscess content has never been published before. Case report: In this report we present a case of tuberculous pleurisy in whom ADA level in the pleural fluid was not higher than expected while it was very high in the drained material of cold abscess due to TB. Conclusion: To the best of our knowledge this is the first case study reporting the measurement of ADA in the content of a cold abscess due to TB. In conclusion, we suggest that ADA measurement in all kinds of liquid or caseous material other than effusions may have a diagnostic role in TB.

The influence of capillary flow on the fate of evaporating wetted imprint of the sessile droplet in porous medium

The fate of a wetting liquid sessile droplet imbibed by a porous medium is formulated as a multiphase flow problem and a numerical solution is developed using the capillary network model with a microforce balance at the liquid∣gas interface. The liquid phase capillary flow and evaporation are solved simultaneously. An exclusive evidence for a multiphase flow is already found in the capillary flow, as a liquid wets a much larger volume of porous medium compared to the wetted volume, calculated by assuming that the medium imbibes the liquid in the single-phase flow. The physics of the multiphase capillary flow includes the formation of local gas clusters and liquid ganglia. The clusters and ganglia distribution is further altered by evaporation. The evaporation tends to shrink the ganglia sizes and open the gas clusters, both due to the liquid mass loss from the porous medium. Still, the capillarity tends to disperse the liquid back into the regions from where the liquid previously evaporated. These changes in the liquid saturation produce the changes in vapor concentration within the porous medium and changes in the mass fluxes. The imprint shape varies, where, for more spherical imprints, the evaporation is enhanced due to the capillary flow. The opposite is true for the elongated imprints for which the capillarity hinders the evaporation rate. Comparing the spherical and elongated imprints, the liquid dispersion differs and the capillary flow the into protrusion direction is pronounced for the elongated imprints. The changes in the liquid dispersion and imprint shape influence the vapor concentration within the porous medium, vapor phase mass fluxes, and liquid persistence time. Finally, the previous behavior is observed for hazardous materials and warfare agents, where predicting the fate of such kind of liquids and their vapors become especially important due to their harmful effects.

Analysis on flow field of piezoelectric pump with unsymmetrical slopes element

Traditional valveless piezoelectric pumps are difficult to be minimized for its special tubes installed outside the chamber. Moreover, the effect of mixing different kinds of liquid is not good. In order to improve the configuration and performance of the pump, a novel valveless piezoelectric pump - valveless piezoelectric pump with unsymmetrical slopes elements (USE) is developed. It is designed aimed at intensing the vortex field in the chamber during pumping. The intense vortex field is helpful to stir and mix different liquids in th e chamber to produce solution, homogeneous emulsion or turbid liquid. Firstly, pumping principle of the proposed pump is analyzed. Then, numerical models are established, and simulation and numerical calculation on the flow fields in the chambers ar e carried out.Finally, experiments are implemented to verify the validity and reliability of numerical analysis.

Modified Eyring viscosity equation and calculation of activation energy based on the liquid quasi-lattice model

Viscosity is an important physical parameter of fluid, and the Eyring viscosity equation is a popular viscosity theory. Based on the Eyring reaction rate equation and Boltzmann statistical theory, and including the probabilities of creating a hole in liquid and the transition to the neighboring hole, a modified Eyring viscosity equation was proposed. According to the structural characteristics of short-range order, liquid is treated as a quasi-lattice structure in a small region. The activation energy, which is the minimum energy needed for the molecule to jump to its neighboring hole because of the restriction of other molecules around it, was analytically calculated from an intermolecular Lennard-Jones potential function and a Stockmayer potential function. The viscosity values of 37 kinds of typical liquids at 25°C and the dependence of viscosity of three kinds of liquids on temperatures were calculated with this modified viscosity equation, and the calculated results agree with the experimental values to some extent. This work not only enriches the understanding of the mechanism of liquid viscosity, but also could provide some theoretical guides for the relevant studies and applications.

Study of liquids absorption and retention capacities of new cellulosic materials and sodium cellulose carboxylmethylate prepared from Posidonia

The Posidonia is a sea plant which is abundant on the Tunisian coasts. Important quantities of Posidonia oceanica fragments are accumulated every year on the beaches which must be cleaned every summer. This plant contains an important ratio of cellulosic materials. On other hand, local sanitary articles industry use important quantities of absorbing materials. The aim of this work is to take advantage of this available biomass by using it as a raw material for the preparation of some of these absorbing materials. In this aim three cellulose qualities of various purities are prepared starting from Posidonia wastes and from these three cellulosic materials six qualities of sodium carboxymethylcellulose (CMCNa) are synthesised, these qualities differ by there substitution degree. The performances of all these materials are evaluated in term of absorption and retention capacities. With this end in view, three kinds of liquids are used: the deionized water, the synthetic urine and the salt solution. Then the evaluated performances are compared with those of some commercial absorbent materials used in local industries (industrial cellulosic pulp and superabsorbant). This comparison shows that the different prepared CMCNa have a retention capacity largely higher than those of the commercial cellulosic pulp. The difference can reaches 405 %. The evaluated absorption capacities of all the prepared CMCNa are generally similar to those of the commercial cellulosic pulp. However the tested superabsorbant presents, in all cases, the best performances in term of liquid absorption and retention.

1609 伸張流動における種々の液体の流動特性に関する研究(OS16-2 非ニュートン流体の流動現象,オーガナイズドセッション)

1609 伸張流動における種々の液体の流動特性に関する研究(OS16-2 非ニュートン流体の流動現象,オーガナイズドセッション)

Development of primary standard for hydrocarbon flow and traceability system of measurement in Japan

It is of importance to establish the hydrocarbon flow standard which acts as the basis for vast dealings and taxation for hydrocarbons, enforcement of the policy on energy savings and high quality management of industries. As a result of investigation into calibration methods, reliability, and effectiveness, the specification of the national primary standard and the traceability system for hydrocarbon flow in Japan was designed. We took the technical initiative in establishing the traceability system using JCSS (Japan Calibration Service System) as basis of the national primary standard in the limited region of flow rates and various kinds of liquids. The national primary standard of high accuracy and safety has been developed. This project was evaluated through verification of international consistency by way of international key comparisons.

1301 伸長流動における種々の液体の圧力損失の特異性に関する研究(OS9-1 マイクロスケールの流動現象および複雑流体の流れ1,オーガナイズドセッション:9)

1301 伸長流動における種々の液体の圧力損失の特異性に関する研究(OS9-1 マイクロスケールの流動現象および複雑流体の流れ1,オーガナイズドセッション:9)

Single Rising Bubble Motion in Aqueous Solution of Electrolyte

Effects of electrolytes on bubble coalescence are investigated experimentally from fluid dynamic point of view. Collisions of a bubble with free surface in two kinds of liquids, namely, ultrapure water and sodium chloride solution, are observed using a high speed camera. It is found that the repetitive number of bubble bounces on a free surface in electrolyte solution is larger than that in ultrapure water when the equivalent bubble radii are the same. This result qualitatively shows that electrolyte works to prevent bubbles from coalescing. It is also revealed that the bubbles can coalesce if their Weber numbers, which are based on the radius of curvature of the front side of the bubble and the approach velocity just before the collision with the free surface, are less than a critical Weber number. Furthermore, the critical Weber number decreases with the increase in the concentration of the electrolyte solutions despite the fluid dynamic characteristics, such as bubble rise velocity and bubble shape, are not affected by the addition of the electrolytes. It is concluded that Weber number is the most important parameter to specify the effects of electrolytes on bubble coalescence.

Parameter estimation in a multidimensional granulation model

A new multidimensional model for wet granulation is presented, which includes particle coalescence, compaction, reaction, penetration, and breakage. In the model, particles are assumed to be spherical and consist of two kinds of solid, two kinds of liquid, and pore volume. The model is tested against experimental results (Simmons, Turton and Mort. Proceedings of Fifth World Congress on Particle Technology, paper 9d, 2006) from the granulation of sugar particles with different PEG based binders in a bench scale mixer, being carried out for different impeller speeds, binder compositions and process durations. The unknown rate constants for coalescence, compaction, reaction, and breakage were fitted to the experiments and the sensitivities of the mass of agglomerates were calculated with respect to these parameters. This is done by employing experimental design and a response surface technique. The simulations with the established set of parameters show that the model predicts the trends, not only in time, but also for crucial process conditions such as impeller speed and the binder composition. As such it is found that more viscous binder promotes the formation of porous particle ensembles. Furthermore, the statistics of the different events such as collisions, coalescence and breakage reveal for instance that successful coalescence events outnumber the breakage events by a factor of up to three for low impeller speeds.

Have the primary structures of biomacromolecules been selected in a Darwinian fashion to adapt to the surrounding environments of our planet?

Have the primary structures of biomacromolecules been selected in a Darwinian fashion to adapt to the surrounding environments of our planet?

混相流研究の進展 ４ 気泡の合体におよぼす電解質の影響

Effects of electrolytes on bubble coalescence are investigated experimentally. Collisions of bubbles with free surface of three kinds of liquids, namely, super purified water, NaCl solution and KCl solution, are observed by using a high speed camera. It is found that the numbers of bounces on a free surface in electrolyte solution are larger than those in super purified water with the same equivalent bubble radius. This result qualitatively indicates that electrolyte works to prevent bubbles from coalescing. It is also revealed that a bubble can coalesce if the Weber number, which is based on radius of curvature of fore side of the bubble and approach velocity just before collision with free surface, is less than a critical value. The decrease of the critical Weber number, which corresponds to the inhibition of the coalescence, is observed with the increase in the concentration of the electrolyte solutions.

An Optical Approach for the Determination of Droplet Volumes in Nanodispensing

This paper looks at the use of drop-on-demand technology in automated life science laboratories. One significant feature of the droplets generated is the enormously high uniformity under constant conditions. However, there is also a relatively strong dependency on environmental conditions. Many different kinds of liquids are used in laboratory applications, some with unknown properties in advance. In light of this and the special way in which the droplets are created, there is one major question which needs answering in relation to the use of this technology in the area of laboratory automation: What is the volume of the drops generated? This paper will present a solution which can be applied in practice. Besides the technical implementation demonstrated, further alternatives will also be presented. Ultimately, dosing systems with greater autonomy should result from the optimizations demonstrated in this paper.

The wettability of polytetrafluoroethylene and polymethylmethacrylate by aqueous solutions of Triton X-100 and propanol mixtures

Measurements of advancing contact angles (θ) were carried out for aqueous solutions of Triton X-100 (TX-100) and propanol mixtures at constant TX-100 concentration equal to 1×10−7, 1×10−6, 1×10−5, 1×10−4, 6×10−4 and 1×10−3M, respectively, on polytetrafluoroethylene (PTFE) and polymethyhmethacrylate (PMMA). Using obtained results the changes of cosθ and adhesional tension against surface tension of all series of aqueous solutions of TX-100 and propanol mixtures (γLV) for PTFE and PMMA surfaces were shown. On the basis of these changes it was deduced that adsorption of TX-100 and propanol mixtures at PTFE-solution and solution-air interfaces is the same but the adsorption of TX-100 and propanol mixtures at solution-air interface is considerably higher than at PMMA-solution one. In the case of PTFE this conclusion was confirmed by relationship between cosθ and the reciprocal of the surface tension of solution. Extrapolation of the relationships between cosθ and/or adhesional tension and the surface tension of solutions to the points corresponding to the cosθ=1 and adhsional tension equal to the surface tension of solution, the critical surface tension of PTFE and PMMA wetting was determined. The average values of critical surface tension of wetting determined from these relationships for PTFE are lying in the range of its surface tension values determined from contact angles of different kinds of liquids, which can be find in the literature, but for PMMA are considerably lower than the surface tension. The double value of the critical surface tension of PTFE wetting is equal to adhesion work of the solution to its surface and for PMMA there is not any correlation between these magnitudes.Using the measured values of the contact angles and Young equation the PTFE(PMMA)-aqueous solution interfacial tension was determined. The interfacial tension values of PTFE-aqueous solution were also calculated from the Fainerman and Miller equation in which the correcting parameter of nonideality of the surface monolayer was introduced and compared to those obtained from Young equation. From this comparison it results that the changes of PTFE-solution interface tension as a function of propanol concentration can be described by the Fainerman and Miller equation.

Prediction of cavitation erosion on stainless steel components in centrifugal pumps

The Research Committee on Cavitation Erosion in the Turbomachinery Society of Japan has already reported the prediction method of cavitation erosion rate. However, the scattering between the predicted rate and the measured rate is 100 times. In this study, we compare fundamental data of stainless steels collected by the Committee with the data obtained in our laboratory. The influence of material and liquid parameters on the scattering of the Committee data is discussed. We found that the scattering was influenced by high liquid temperature, the kind of liquids, the microstructure of components and the operating life. We propose a modified prediction equation including these parameters, and found that the equation improve the accuracy of the erosion prediction.