A Rheological Model for Cupuassu (Theobroma grandiflorum) Pulp at Different Concentrations and Temperatures

AbstractThis work was made aiming at studying the best model for the rheological properties of Cupuassu (Theobroma grandiflorum, Schum) pulps with 14 (in nature), 17, 19, 23 and 25°Brix of total soluble solids (TSS) which were measured at 20, 30, 40, 50 and 60°C temperature using a concentric cylinder rheometer. The results were adjusted to the following nine models: Ostwald-de-Waele (power law), Bingham, Casson, Generalized Casson, Heinz–Casson, Herschel–Bulkley, Mizrahi–Berk, Schulmann–Haroske–Reher and Windhab. The parameters of the best model were correlated with pulp temperature and TSS by polynomial regression analysis and were kept in the regression equation only those parameters that contributed more than 1% to the variation of the independent variable. The results indicate that the rheological behavior of Cupuassu pulp in different concentrations and temperatures can be modeled by the Windhab model, although other models can be used in a narrower band of shear stress.

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Rheological behavior of mixed drink of annona and milk

Engenharia Agrícola ◽

10.1590/s0100-69162012000200013 ◽

2012 ◽

Vol 32 (2) ◽

pp. 333-341

Author(s):

Maria E. M. Duarte ◽

Deyzi S. Gouveia ◽

Mario E. R. M. C. Mata ◽

Alexandre J. de M. Queiroz

Keyword(s):

Power Law ◽

Rheological Behavior ◽

Physicochemical Parameters ◽

Soluble Solids ◽

Effect Of Temperature ◽

Rheological Parameters ◽

Annona Squamosa ◽

Concentric Cylinder ◽

Different Temperatures ◽

Behavior Index

In this study the rheological behavior in different temperatures (0; 6; 18 e 24 ºC) and physicochemical parameters of integral annona (Annona squamosa) pulp and the annona pulp with milk in different percentages pulp/milk (75g of annona pulp/25g of milk, 50g of annona pulp/50g of milk, 25g of annona pulp/75g of milk) have been availed, in order to verify the effect of temperature and pulp concentration in the rheological behavior of these beverages. To obtain the rheological parameters a concentric cylinder rheometer has been used and the rheograms were analyzed using the Ostwald-de-Wael (power Law) and Herschel-Bulkley models. The physicochemical parameters (sugars, pH, ash, acidity and soluble solids) were determined in order to establish correlations with the rheological behavior. Finally, the best results had been obtained using the Herschel-Bulkley model; the low values for the behavior index (n <1) obtained confirm the pseudoplastic behavior of all samples.

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Rootstock-scion interaction:5. Effect on the evolution of Cabernet Sauvignon grape ripening

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452019138 ◽

2019 ◽

Vol 41 (3) ◽

Author(s):

Alberto Miele ◽

Luiz Antenor Rizzon

Keyword(s):

Principal Component Analysis ◽

Regression Analysis ◽

Yield Components ◽

Polynomial Regression ◽

Principal Component ◽

Titratable Acidity ◽

Soluble Solids ◽

Cabernet Sauvignon ◽

Total Soluble Solids ◽

Wine Composition

Abstract The rootstock effect on grapevine yield components, grape must and wine composition and wine sensory characteristics were evaluated in previous studies. This experiment carried out over five years had the objective to determine the effect of the rootstock on the evolution of variables related to sugar and acidity contents of the juice during grape ripening. The treatments consisted of Cabernet Sauvignon grapevine grafted on rootstocks such as Rupestris du Lot, 101- 14 Mgt, 3309 C, 420A Mgt, 5BB K, 161-49 C, SO4, Solferino, 1103 P, 99 R, 110 R, Gravesac, Fercal, Dogridge and Isabel. The berries were sampled during the grape ripening period, on nine dates during the summer of each year. Taken to the laboratory, they were hand crushed and the juice was centrifuged to separate the solid and liquid phase, where the supernatant was then used for physicochemical analyses. The data were submitted to Principal Component Analysis (PCA) and polynomial regression analysis. The main results show that, at grape maturity, the PCA discriminated mainly the juices of CS/101-14 Mgt, CS/SO4 and CS/Gravesac, which had high density, total soluble solids, total soluble solids/titratable acidity ratio and pH, and CS/Dogridge and CS/Fercal, which had high titratable acidity. The density, total soluble solids, titratable acidity, total soluble solids/titratable acidity ratio increased as grape ripened, but the titratable acidity decreased. However, the increase or decrease rates were lower at the end of the grape ripening cycle according to the variable, and the total soluble solids having the highest increase (116.3%) and the titratable acidity the highest decrease (68.3%).

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RHEOLOGICAL ANALYSIS OF VEGETABLE OILS USED FOR BIODIESEL PRODUCTION IN BRAZIL

Revista de Engenharia Térmica ◽

10.5380/reterm.v14i2.62129 ◽

2015 ◽

Vol 14 (2) ◽

pp. 31 ◽

Cited By ~ 1

Author(s):

L. E. Silva ◽

C. A. C. Santos ◽

J. E. S. Ribeiro ◽

C. C. Souza ◽

A. M. S. Sant’Ana

Keyword(s):

Shear Stress ◽

Rheological Properties ◽

Vegetable Oils ◽

Rheological Behavior ◽

Apparent Viscosity ◽

Biodiesel Production ◽

Viscosity Data ◽

Concentric Cylinder ◽

Lower Shear ◽

Different Temperatures

Rheology attempts to define a relationship between the stress acting on a given material and the resulting deformation and/or flow that takes place. Thus, the knowledge of rheological properties of fluid materials such as vegetable oils generates auxiliary data that can be used in its storage and application. In this context, the aim of this study was to evaluate the rheological behavior of vegetable oils (cotton, canola, sunflower, corn and soybean) at different temperatures, using four rheological models (Ostwald- de-Waelle, Herschel-Bulkley, Newton and Bingham). The rheological properties were determined using a Thermo Haake rheometer with concentric cylinder geometry. Measurements were taken at 30, 45 and 60 °C by controlling the temperature using a thermostatic bath coupled to the equipment. The software Rheowin Pro Job Manager was used for process control and data record. The rheograms were obtained by measuring the values of shear stress varying the shear rate from 100 to 600 s-1 within 250 seconds. For the analysis of the apparent viscosity at different shear rates was applied simple linear regression until 2nd degree with the aid of SAS (SAS/Stat 9.2) program. The apparent viscosity data were submitted to analysis of variance and the averages were compared by Tukey test at 5% of probability. Higher temperatures of the samples were correlated to lower shear stress values, hence lower values for viscosity and consistency index were obtained, since it is known that the density and viscosity are highly sensitive to temperature and that the increase in temperature results in reduction of viscosity, benefiting the fluid flow. The models of Newton and Ostwald-de-Waelle were chosen to evaluate the rheological behavior of the samples, showing a good fit for the rheological data.

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Sensory Evaluation and Rheological Behavior of Commercial Mayonnaise

International Journal of Food Engineering ◽

10.2202/1556-3758.1094 ◽

2007 ◽

Vol 3 (1) ◽

Cited By ~ 10

Author(s):

Dayane Izidoro ◽

Maria-Rita Sierakowski ◽

Nina Waszczynskyj ◽

Charles W. I. Haminiuk ◽

Agnes de Paula Scheer

Keyword(s):

Shear Stress ◽

Yield Stress ◽

Sensory Evaluation ◽

Rheological Behavior ◽

Oil Content ◽

Sensory Attributes ◽

Rheological Parameters ◽

Low Fat ◽

Concentric Cylinder ◽

Rheological Characterization

The effects of ingredients on the sensory evaluation and rheological behavior of two brands of mayonnaise were examined in this work. Mayonnaise samples were examined by Analytical Descriptive Test and Ranking Test of Preference. The rheological parameters were determined at 25°C using a concentric cylinder Brookfield rheometer with a spindle SC4-34. The results showed that standard mayonnaise as opposed to low-fat mayonnaise gained higher grades for most sensory attributes. All samples were found to exhibit non-Newtonian pseudoplastic behavior described by HerschelBulkley model. A decrease in the yield stress, viscosity and shear stress with the decrease in oil content was observed in all products, which confirm that the rheological characterization is capable of distinguishing rather well between mayonnaises made with different formulation.

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Digital Trading Applications and Bank Performance: Evidence from Russia

Journal of Open Innovation Technology Market and Complexity ◽

10.3390/joitmc7030194 ◽

2021 ◽

Vol 7 (3) ◽

pp. 194

Author(s):

Anton Lisin ◽

Kristina Shvandar ◽

Artur Meynkhard ◽

Mafura Uandykova ◽

Serhat Yuksel ◽

...

Keyword(s):

Regression Analysis ◽

High Efficiency ◽

Polynomial Regression ◽

Mobile Apps ◽

Banking System ◽

Financial Sector ◽

T Test ◽

Bank Performance ◽

Smart Contracts ◽

Independent Variable

Digital trading apps are evidence of developing open innovations in the financial sector. The investment industry (including banks and brokers) can greatly benefit from the utilization of digital trading applications and corresponding tools, such as smart contracts. The goal of this research paper is to examine the possibility that brokers’ existing mobile apps outperform banks without mobile apps in the Russian financial sector. The efficiency of brokers is compared to banks in Russia. The results of these institutions’ activities are related to the number of profitable banks, which declines as a sign of high efficiency. The paper uses methods of t-test, linear and polynomial regression analysis between assets (dependent variable) and the profit to assets (independent variable) in Russia. The article finds the different directions of the utilization of the discussed technology, and they all share the consequential growth after the technology’s introduction. The paper also discusses the various areas of digital trading apps implementation and the future contributions for the Russian banking system and economy.

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Gypsum Mud Rheological Behavior

Journal of Petroleum Research and Studies ◽

10.52716/jprs.v7i3.156 ◽

2021 ◽

Vol 7 (3) ◽

pp. 28-50

Author(s):

Wissam H. AL-Hashimi

Keyword(s):

Yield Point ◽

Power Law ◽

Rheological Behavior ◽

Plastic Viscosity ◽

Soluble Solids ◽

Oil Well ◽

Rheological Models ◽

Well Drilling ◽

Increasing Temperature ◽

Modified Power Law

Gypsum muds are considered as the most important ones used in oil well drilling due to their thermal stability in addition to the durability of their ingredients. The main aim of this work is to study the effect of the gypsum mud compositions on their rheological behavior under the conditions of high-pressure and high temperature. Eleven samples of gypsum mud were tested using Fann viscometer model 50-C. All the tested samples had the same trend of reduction in both plastic viscosity and yield point with increasing temperature. The results showed that with 5 ppb of Q Broxine thermal degradation is obtained at approximately 150 0 F; this is due to the over treatment with thinner which result in more soluble solids and higher rheological properties while the decrement in NaOH concentration from 0.7 ppb to 0.35 ppb results in an increase in both yield point and plastic viscosity; this is due to the loss of OH-1 ions. Six rheological models were adopted: Bingham, power law, modified power law, Robertson stiff, modified Robertson stiff and Casson. Both Robertson stiff model and Casson model showed more acceptable values that fit the experimental data accurately.

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PENGARUH MOTIVASI KERJA, KOMUNIKASI INTERPERSONAL DAN BUDAYA ORGANISASI TERHADAP KINERJA GURU (STUDI KASUS DI SMPN 5 PARIAMAN)

10.31219/osf.io/es2bn ◽

2020 ◽

Author(s):

Hasnah Mila

Keyword(s):

Organizational Culture ◽

Regression Analysis ◽

Interpersonal Communication ◽

Work Motivation ◽

Employee Performance ◽

High Reliability ◽

Eligibility Criteria ◽

Validity Test ◽

Independent Variable ◽

Performance Teachers

The independent independent variables in this study are Work Motivation, Interpersonal Communication and Organizational Culture while the dependent variable is the Performance Teachers and Employees SMPN 5 Pariaman. The sample used in this study as many as 32 respondents determined by using saturated samples. To know the influence of independent variable to dependent variable partially, used t test. While to know the effect of independent variable to dependent variable simultaneously, used F test. The assumption used in the validity test is if R-count> R-table item is declared valid. The R-arithmetic shown in the table above, from each item indicates that R-arithmetic> R-table so the item is declared valid. Based on the validity test of Work Motivation instrument, Interpersonal Communication and Organizational Culture on Teacher and Employee Performance, all items are declared valid and reliability test results indicate that the instrument has high reliability. This means that the eligibility criteria Instrument Motivation Work, Interpersonal Communication and Organizational Culture on Performance Teachers and Employees have met the criteria of good instrument requirements, namely valid and reliable. Regression analysis results obtained t count = 2.550 while t table = 2.042 so thitung> ttable and significance value is 0.000, this value is smaller than α = 0,05 so it can be said that motivation factor (X1) (Y) Regression analysis results obtained t count = 1.076 while the value of t table = 2.042 so that tcount < ttable or and its not significance value is 0.000, this value is smaller than α = 0,05, and proved variable of Interpersonal Communication (X2) (Y) Regression analysis results obtained t count = 1.715 while the value of t table = 2.042 so thitung< ttable and its not significance value is 0.000, this value is smaller than α = 0,05, and proved Organizational Culture variable (X3) The value of correlation coefficient (R) turns out that the correlation is positive. This means that there is a strong one-way relationship, where the change of increment that occurs in the free factor of Work Motivation, Personal Communication and Organizational Culture is accompanied by the change of the bound factor increase that is Teacher Performance (Y).

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PENGARUH GAYA KEPEMIMPINAN, MOTIVASI KERJA DAN KOMPETENSI TERHADAP KINERJA PEGAWAI PADA DINAS PEMBERDAYAAN MASYARAKAT DAN DESA PROVINSI SUMATERA BARAT

10.31219/osf.io/sqm5k ◽

2020 ◽

Author(s):

Mafral

Keyword(s):

Regression Analysis ◽

Leadership Style ◽

Work Motivation ◽

Employee Performance ◽

High Reliability ◽

Test Results ◽

Eligibility Criteria ◽

Validity Test ◽

Negative Effect ◽

Independent Variable

The independent independent variables in this study as many as 89 respondents are determined by using saturated samples. To know the influence of independent variable to dependent variable partially, used t test. While to know the effect of independent variable to dependent variable simultaneously, used F test. The assumption used in the validity test is if R-count> R-table item is declared valid. The R-arithmetic shown in the table above, from each item indicates that R-arithmetic> R- table so the item is declared valid. Based on the validity test of the instrument of Leadership Style, Work Motivation, and Competence on Employee Performance, all items are declared valid and reliability test results indicate that the instrument has high reliability. This means that the eligibility criteria of the Instrument of Leadership Style, Work Motivation, Competency and Employee Performance have met the criteria of good instrument requirements, that is valid and reliable. The result of regression analysis of Leadership Style obtained by tcount = 20,91 while ttable value = 1,988 tcount> ttable proved variable of Leadership Style influence to Employee Performance. Work Motivation regression analysis obtained tcount = 17.62 while the value ttable = 1.988 tcount> ttabel proven Motivational Work variables influence on Employee Performance. Regression analysis Competence obtained value tcount = - 06.85 while ttable =1.988 so thitung> ttable and proven variable Competence have a negative effect on Employee Performance.

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Analisa Pemilihan Moda Transportasi Umum Rute Tanjung Karang – Bandara Radin Inten II Dengan Stated Preference dan Uji Crame’s V

Borneo Engineering : Jurnal Teknik Sipil ◽

10.35334/be.v2i2.621 ◽

2018 ◽

Vol 2 (2) ◽

pp. 137

Author(s):

Muhammad Abi Berkah Nadi

Keyword(s):

Regression Analysis ◽

Utility Function ◽

Stated Preference ◽

Technical Analysis ◽

Chi Square ◽

Time Headway ◽

Independent Variable ◽

The Relationship ◽

Selection Of

Radin Inten II Airport is a national flight in Lampung Province. In this study using the technical analysis stated preference which is the approach by conveying the choice statement in the form of hypotheses to be assessed by the respondent. By using these techniques the researcher can fully control the hypothesized factors. To determine utility function for model forecasting in fulfilling request of traveler is used regression analysis with SPSS program. The analysis results obtained that the passengers of the dominant airport in the selection of modes of cost attributes than on other attributes. From the result of regression analysis, the influence of independent variable to the highest dependent variable is when the five attributes are used together with the R square value of 8.8%. The relationship between cost, time, headway, time acces and service with the selection of modes, the provision that states whether or not there is a decision. The significance of α = 0.05 with chi-square. And the result of Crame's V test average of 0.298 is around the middle, then the relationship is moderate enough.

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Shear Loss Characteristics of an Aerobic Biofilm

Water Science & Technology ◽

10.2166/wst.1992.0439 ◽

1992 ◽

Vol 26 (3-4) ◽

pp. 595-600 ◽

Cited By ~ 10

Author(s):

S. M. Rao Bhamidimarri ◽

T. T. See

Keyword(s):

Growth Rate ◽

Shear Stress ◽

Film Thickness ◽

Removal Rate ◽

Surface Growth ◽

Phenol Removal ◽

Concentric Cylinder ◽

Substrate Utilisation ◽

Utilisation Rate ◽

Net Growth Rate

Growth and shear loss characteristics of phenol utilizing biofilm were studied in a concentric cylinder bioreactor. The net accumulation of the biofilm and the substrate utilisation were measured as a function of torque. Uniform biofilms were obtained up to a thickness of around 300 microns, beyond which the surface growth was non-uniform. The substrate utilisation rate, however, reached a constant value beyond film thickness of 50 to 100 microns depending on the operational torque. The maximum phenol removal rate was achieved at a shear stress of 3.5 Nm-2. The effect of shear stress on net growth rate was found to be described byand a zero net growth was obtained at a shear stress of 18.7 Nm-2.

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