Countercurrent pulsed and reciprocating plate extractors. Prediction of Sauter mean drop diameter

1990 ◽  
Vol 55 (2) ◽  
pp. 409-425 ◽  
Author(s):  
Helena Sovová
Keyword(s):  
Experimental Data ◽  
Standard Deviation ◽  
Drop Size ◽  
Data Sources ◽  
Drop Diameter ◽  
General Validity ◽  
Best Fit

Six published correlations for Sauter diameter d32 in pulsed and reciprocating plate columns are compared with drop size measurements from seven different data sources. The correlation of Kumar and Hartland gives the best fit of data in the whole range of agitation rates. Also the semiempiric equations of Misek and of Boyadzhiev and Spassov are of general validity at higher agitation levels. A new semiempiric equation covering the whole range of agitation rates and describing experimental data with a standard deviation of 10% is presented.

Discuss of Important Issues in Numerical Simulation for Natural Draft Counter Flow Cooling Tower

2012 ◽  
Vol 516-517 ◽  
pp. 267-270
Author(s):  
Li Song ◽  
Rui Tian ◽  
Song Li ◽  
Ya Hui Wang
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Mass Transfer ◽  
Drop Size ◽  
Cooling Tower ◽  
Drop Diameter ◽  
Atmospheric Density ◽  
Counter Flow ◽  
Natural Draft ◽  
Calculation Results

natural draft counter flow cooling tower heat and mass transfer numerical simulation has been widely used to optimize the cooling tower design and to improve the thermal efficiency, but in published papers, a few important problems is not attracted attention, such as how does impact grid density to the calculation results; how does impact change of atmospheric density to the calculation results; drop diameter is an important parameter in numerical simulation, but it is not a exact experimental data, it is important to discuss how does impact drop size to the calculation results. This paper will explore and analyze these issues in the numerical simulation.

scholarly journals Smart Design Nano-Hybrid Formulations by Machine Learning

Proceedings ◽  
2020 ◽  
Vol 78 (1) ◽  
pp. 5
Author(s):  
Raquel de Melo Barbosa ◽  
Fabio Fonseca de Oliveira ◽  
Gabriel Bezerra Motta Câmara ◽  
Tulio Flavio Accioly de Lima e Moura ◽  
Fernanda Nervo Raffin ◽  
...  
Keyword(s):  
Machine Learning ◽  
Experimental Data ◽  
Water Solubility ◽  
Inorganic Materials ◽  
Fine Tuning ◽  
Support Vector ◽  
Drug Solubility ◽  
Physical Behavior ◽  
Best Fit

Nano-hybrid formulations combine organic and inorganic materials in self-assembled platforms for drug delivery. Laponite is a synthetic clay, biocompatible, and a guest of compounds. Poloxamines are amphiphilic four-armed compounds and have pH-sensitive and thermosensitive properties. The association of Laponite and Poloxamine can be used to improve attachment to drugs and to increase the solubility of β-Lapachone (β-Lap). β-Lap has antiviral, antiparasitic, antitumor, and anti-inflammatory properties. However, the low water solubility of β-Lap limits its clinical and medical applications. All samples were prepared by mixing Tetronic 1304 and LAP in a range of 1–20% (w/w) and 0–3% (w/w), respectively. The β-Lap solubility was analyzed by UV-vis spectrophotometry, and physical behavior was evaluated across a range of temperatures. The analysis of data consisted of response surface methodology (RMS), and two kinds of machine learning (ML): multilayer perceptron (MLP) and support vector machine (SVM). The ML techniques, generated from a training process based on experimental data, obtained the best correlation coefficient adjustment for drug solubility and adequate physical classifications of the systems. The SVM method presented the best fit results of β-Lap solubilization. In silico tools promoted fine-tuning, and near-experimental data show β-Lap solubility and classification of physical behavior to be an excellent strategy for use in developing new nano-hybrid platforms.

scholarly journals Unbinding of Hyaluronan Accelerates the Enzymatic Activity of Bee Hyaluronidase

2011 ◽  
Vol 286 (41) ◽  
pp. 35699-35707 ◽  
Author(s):  
Attila Iliás ◽  
Károly Liliom ◽  
Brigitte Greiderer-Kleinlercher ◽  
Stephan Reitinger ◽  
Günter Lepperdinger
Keyword(s):  
Experimental Data ◽  
Quartz Crystal ◽  
Surface Loop ◽  
X Ray ◽  
Site Model ◽  
Substrate Interaction ◽  
Close Proximity ◽  
Binding Groove ◽  
The One ◽  
Best Fit

Hyaluronan (HA), a polymeric glycosaminoglycan ubiquitously present in higher animals, is hydrolyzed by hyaluronidases (HAases). Here, we used bee HAase as a model enzyme to study the HA-HAase interaction. Located in close proximity to the active center, a bulky surface loop, which appears to obstruct one end of the substrate binding groove, was found to be functionally involved in HA turnover. To better understand kinetic changes in substrate interaction, binding of high molecular weight HA to catalytically inactive HAase was monitored by means of quartz crystal microbalance technology. Replacement of the delimiting loop by a tetrapeptide interconnection increased the affinity for HA up to 100-fold, with a KD below 1 nm being the highest affinity among HA-binding proteins surveyed so far. The experimental data of HA-HAase interaction were further validated showing best fit to the theoretically proposed sequential two-site model. Besides the one, which had been shown previously in course of x-ray structure determination, a previously unrecognized binding site works in conjunction with an unbinding loop that facilitates liberation of hydrolyzed HA.

Comparative study of isotherm parameters of lead biosorption by two wastes of olive-oil production

2015 ◽  
Vol 72 (5) ◽  
pp. 711-720 ◽  
Author(s):  
G. Blázquez ◽  
A. Ronda ◽  
M. A. Martín-Lara ◽  
A. Pérez ◽  
M. Calero
Keyword(s):  
Experimental Data ◽  
Olive Tree ◽  
Langmuir Equation ◽  
Equilibrium Isotherm ◽  
Chemical Treatments ◽  
Olive Stone ◽  
Loss Of Mass ◽  
Best Fit ◽  
Tree Pruning ◽  
Effectiveness Coefficient

Batch isotherm studies were carried out on a laboratory scale: (i) to investigate the effectiveness to remove lead of two wastes (olive stone (OS) and olive tree pruning (OTP)), untreated and chemically treated; and (ii) to examine the applicability of various adsorption isotherms to fit the experimental data. Results from tests were analyzed using seven equilibrium isotherm correlations (Langmuir, Freundlich, Dubinin–Radushkevich, Temkin, Redlich–Peterson, Sips, and Toth equations). The sum of the squares of the errors was determined for each isotherm and the Langmuir equation provided the best fit. Chemical treatments increased the biosorption properties of these materials. The maximum biosorption capacities were: 6.33, 49.13, 14.83, and 38.93 mg g−1 for untreated OS, HNO3-OS, H2SO4-OS, and NaOH-OS, respectively, and 26.72, 86.40, 72.78, and 123.80 mg g−1 for untreated OTP, HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively. Finally, the loss of mass for each waste (13.9, 14.3, and 36.8% for HNO3-OS, H2SO4-OS, and NaOH-OS and 35.1, 27.5, and 46.7% for HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively) was taken into account and an effectiveness coefficient was determined for each adsorbent material.

Differentiating Freezing Drizzle and Freezing Rain in HRRR Model Forecasts

2021 ◽  
Author(s):  
Sarah Tessendorf ◽  
Allyson Rugg ◽  
Alexei Korolev ◽  
Ivan Heckman ◽  
Courtney Weeks ◽  
...  
Keyword(s):  
Drop Size ◽  
Prediction Models ◽  
Water Drop ◽  
Weather Prediction ◽  
Supercooled Liquid ◽  
Drop Diameter ◽  
Aircraft Icing ◽  
Freezing Rain ◽  
Primary Focus

AbstractSupercooled large drop (SLD) icing poses a unique hazard for aircraft and has resulted in new regulations regarding aircraft certification to fly in regions of known or forecast SLD icing conditions. The new regulations define two SLD icing categories based upon the maximum supercooled liquid water drop diameter (Dmax): freezing drizzle (100–500 μm) and freezing rain (> 500 μm). Recent upgrades to U.S. operational numerical weather prediction models lay a foundation to provide more relevant aircraft icing guidance including the potential to predict explicit drop size. The primary focus of this paper is to evaluate a proposed method for estimating the maximum drop size from model forecast data to differentiate freezing drizzle from freezing rain conditions. Using in-situ cloud microphysical measurements collected in icing conditions during two field campaigns between January and March 2017, this study shows that the High-Resolution Rapid Refresh model is capable of distinguishing SLD icing categories of freezing drizzle and freezing rain using a Dmax extracted from the rain category of the microphysics output. It is shown that the extracted Dmax from the model correctly predicted the observed SLD icing category as much as 99% of the time when the HRRR accurately forecast SLD conditions; however, performance varied by the method to define Dmax and by the field campaign dataset used for verification.

scholarly journals Mathematical modeling and determination of thermodynamic properties of jabuticaba peel during the drying process

2016 ◽  
Vol 20 (6) ◽  
pp. 576-580 ◽  
Author(s):  
Cristian F. Costa ◽  
Paulo C. Corrêa ◽  
Jaime D. B. Vanegas ◽  
Fernanda M. Baptestini ◽  
Renata C. Campos ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thermodynamic Properties ◽  
Drying Process ◽  
Drying Temperature ◽  
Air Temperatures ◽  
Nutritional Qualities ◽  
Forced Air ◽  
Air Circulation ◽  
Best Fit

ABSTRACT Jabuticaba is a fruit native of Brazil and, besides containing many nutritional qualities, it also has a good field for use in products such as flour for cakes and biscuits, juice, liqueur, jelly and others. This study aimed to model the drying kinetics and determine the thermodynamic properties of jabuticaba peel at different drying air temperatures. Ripe fruits of jabuticaba (Myrciaria jaboticaba) were collected and pulped manually. Drying was carried out in a forced-air circulation oven with a flow of 5.6 m s-1 at temperatures of 40, 50, 60 and 70 °C. Six mathematical models commonly used to represent the drying process of agricultural products were fitted to the experimental data. The Arrhenius model was used to represent the drying constant as a function of temperature. The Midilli model showed the best fit to the experimental data of drying. The drying constant increased with the increment in drying temperature and promoted an activation energy of 37.29 kJ mol-1. Enthalpy and Gibbs free energy decreased with the increase in drying temperature, while entropy decreased and was negative.

scholarly journals Drying kinetics of ‘babassu’ mesocarp

2017 ◽  
Vol 21 (10) ◽  
pp. 709-714 ◽  
Author(s):  
Jhonatas C. Rosa ◽  
Andreza P. Mendonça ◽  
Angélica dos S. Oliveira ◽  
Sylviane B. Ribeiro ◽  
Andréia do R. Batista ◽  
...  
Keyword(s):  
Experimental Data ◽  
Water Content ◽  
Animal Feed ◽  
Coefficient Of Determination ◽  
Residual Distribution ◽  
Solar Dryer ◽  
Error Standard Deviation ◽  
Forced Air ◽  
Final Water Content ◽  
Best Fit

ABSTRACT ‘Babassu’ mesocarp flour has been used by the pharmaceutical, human food and animal feed industries. However, there is lack of standardization in the production, as well as absence of information on the management of the product’s quality. Thus, the objective of this study was to dry the ‘babassu’ mesocarp in forced-air oven and solar dryer, adjust different mathematical models to the experimental data, as well as to quantify the levels of proteins and crude fiber of the produced flour. The criteria for the adjustment were the coefficient of determination, magnitude of the mean relative error, standard deviation of estimate and the residual distribution trend. Drying in the shortest time occurred in oven at 60 °C (370 min), leading to water content of 4.62%, while in the solar dryer the final water content was 8.07% in 6 days. The mathematical model Two Terms showed the best fit to the experimental data for oven drying and the Midilli model showed the best fit in solar dryer. There was an increase in protein content with the drying in solar dryer and oven at 40, 50 and 60 °C (1.36, 1.33, 1.15 and 1.37%, respectively) in relation to fresh mesocarp (0.88%). Drying in both oven and solar dryer promoted increase of protein in the flour.

scholarly journals Application of descriptive statistics in analysis of experimental data

2008 ◽  
Vol 62 (1-2) ◽  
pp. 85-95
Author(s):  
Milorad Mirilovic ◽  
Ivana Pejin
Keyword(s):  
Experimental Data ◽  
Statistical Analysis ◽  
Standard Deviation ◽  
Arithmetic Mean ◽  
Descriptive Statistics ◽  
Qualitative Investigation ◽  
Scientific Methods ◽  
The Subject ◽  
Variation Interval ◽  
Descriptive Statistical Analysis

Statistics today represent a group of scientific methods for the quantitative and qualitative investigation of variations in mass appearances. In fact, statistics present a group of methods that are used for the accumulation, analysis, presentation and interpretation of data necessary for reaching certain conclusions. Statistical analysis is divided into descriptive statistical analysis and inferential statistics. The values which represent the results of an experiment, and which are the subject of observation of a certain occurrence, are called parameters and they are divided into descriptive and numerical. All numerical parameters are divided into non-continuous and continuous. The graphic presentation of the distribution of frequencies can be by poligon or histogram. The most frequently applied descriptive statistical methods are: arithmetic mean, standard deviation, standard error of arithmetic mean, variation coefficient, and variation interval.

scholarly journals Mathematical modeling of pequi pulp drying and effective diffusivity determination

2017 ◽  
Vol 21 (7) ◽  
pp. 493-498 ◽  
Author(s):  
Elisabete P. de Sousa ◽  
Rossana M. F. de Figueirêdo ◽  
Josivanda P. Gomes ◽  
Alexandre J. de M. Queiroz ◽  
Deise S. de Castro ◽  
...  
Keyword(s):  
Experimental Data ◽  
Effective Diffusivity ◽  
Drying Kinetics ◽  
Convective Drying ◽  
Drying Time ◽  
Air Speed ◽  
Drying Curves ◽  
Increasing Temperature ◽  
Kinetics Of ◽  
Best Fit

ABSTRACT The aim of this work was to study the drying kinetics of pequi pulp by convective drying at different conditions of temperature (50, 60, 70 and 80 °C) and thickness (0.5, 1.0 and 1.5 cm) at the air speed of 1.0 m s-1, with no addition of adjuvant. The experimental data of pequi pulp drying kinetics were used to plot drying curves and fitted to the models: Midilli, Page, Henderson & Pabis and Newton. Effective diffusivity was calculated using the Fick’s diffusion model for a flat plate. It was found that, with increasing thickness, the drying time increased and, with increasing temperature, the drying time was reduced. The Midilli model showed the best fit to the experimental data of pequi pulp drying at all temperatures and thicknesses, presenting higher coefficients of determination (R2), indicating that this model satisfactorily represents the pequi pulp drying phenomenon. There was a trend of increase in the effective diffusivity with the increase in pulp layer thickness and temperature.

scholarly journals Redefining Existing Concrete Compressive Strength Acceptance Standard in Iran Concrete Code (ABA), by Experimental Data

2018 ◽  
Vol 4 (5) ◽  
pp. 1127
Author(s):  
Iman Mohammadi Bidsardareh ◽  
Mohammad Mohammadi
Keyword(s):  
Experimental Data ◽  
Compressive Strength ◽  
Standard Deviation ◽  
Geographical Area ◽  
Field Studies ◽  
Concrete Compressive Strength ◽  
Main Hypothesis ◽  
Internet Studies ◽  
International Projects ◽  
Deviation Factor

In Iran Concrete Code (ABA), the criteria for calculation of standard deviation (s) are comprehensive and holistic. However, if it would be determined separately for each geographical area, significant changes could occur due to the use of concrete as one of the common materials. This paper analyses the criteria and redefines the acceptance standards for concrete compressive strength in ABA using experimental data available in Kohgiluyeh and Boyer-Ahmad and Fars provinces. The main hypothesis of the study is that using the statistical analysis of the test specimens for three categories C21, C30 and C35 in various projects located in Kohgiluyeh and Boyer-Ahmad and Fars provinces, extracting standard deviations, mean and the compressive strength of the specimens and their comparison with ABA proposed relationships and values, it is possible to propose new amendments for these areas in line with economic savings in national and international projects. In this study using the quantitative Strategy, library - Internet studies, field studies and in cooperation with the concrete labs, required information for 4878 concrete specimens was collected from the above-mentioned areas. By analysing the acceptance regulations for the specimens based on ABA and comparing the standard deviation of these data with the formulas of the regulations, significant results were obtained for the standard deviation factor correction and finally some formulas were suggested for the acceptance of the concrete specimens.

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