Effect of Operational Parameters on Determination of Oxidative Stability Measured by Rancimat Method

The study sought to investigate the effect of roasting temperatures on antioxidant components and oxidative stability of peanut oils. The total phenolic content, total flavonoid content, α–tocopherol content, and phytosterol content in peanut oils was influenced by roasting at temperatures of 120 °C, 140 °C, and 160 °C, while those roasting temperatures had no effect on the fatty acid profile and γ–tocopherol content of peanut oils. Roasting promotes the quality of peanut oil aroma via the Maillard reaction, particularly when it is derived from N–heterocyclic compounds (such as pyrazine and pyrrole). The oxidative stability of peanut oils was investigated using the Rancimat method, and the results show that there is a linear relationship between roasting and natural logarithm of the induction period (R2: 0.959~0.998). This was determined based on the Arrhenius equation, which indicated the activation energy (Ea) was in the range of 82.08~108.61 kJ/mol. In principal component analysis (PCA) analysis, the antioxidant stability of the increase levels of phenols released in the peanut oils was found to rise with the increment of roasting temperatures. The data obtained in this study should be confirmed as the nutritional benefits of peanut oils that will be most appealing to consumers.

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New HFC/HFO Blends as Refrigerants for the Vapor-Compression Refrigeration System (VCRS)

Energies ◽

10.3390/en14040946 ◽

2021 ◽

Vol 14 (4) ◽

pp. 946

Author(s):

Bartosz Gil ◽

Anna Szczepanowska ◽

Sabina Rosiek

Keyword(s):

Global Warming ◽

Global Warming Potential ◽

Mass Fraction ◽

Vapor Compression ◽

Refrigeration System ◽

Operational Parameters ◽

Vapor Compression Refrigeration ◽

Low Global Warming Potential ◽

Triangular Design

In this work, which is related to the current European Parliament Regulation on restrictions affecting refrigeration, four new three-component refrigerants have been proposed; all were created using low Global Warming Potential(GWP) synthetic and natural refrigerants. The considered mixtures consisted of R32, R41, R161, R152a, R1234ze (E), R1234yf, R1243zf, and RE170. These mixtures were theoretically tested with a 10% step in mass fraction using a triangular design. The analysis covered two theoretical cooling cycles at evaporating temperatures of 0 and −30 °C, and a 30 °C constant condensing temperature. The final stage of the work was the determination of the best mixture compositions by thermodynamic and operational parameters. R1234yf–R152a–RE170 with a weight share of 0.1/0.5/0.4 was determined to be the optimal mixture for potentially replacing the existing refrigerants.

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Determination of Bio Content in Polymers used in the Packaging of food Products

Radiocarbon ◽

10.1017/rdc.2019.141 ◽

2019 ◽

Vol 61 (6) ◽

pp. 1973-1981

Author(s):

C Telloli ◽

A Rizzo ◽

C Canducci ◽

P Bartolomei

Keyword(s):

Food Packaging ◽

Liquid Scintillation ◽

Scintillation Counting ◽

Operational Parameters ◽

Original Design ◽

Plastic Materials ◽

Different Types ◽

Scintillation Method

ABSTRACTThe ENEA Radiocarbon Laboratory (Bologna, Italy) has been operating since 1985; it is the oldest among such laboratories operating in Italy and has been active for about 30 years in the field of dating of different types of samples with the radiocarbon (14C) liquid scintillation method. This study shows the detailed procedure for radiocarbon analysis on bioplastic materials by means of the synthesis of benzene, which includes CO2 production and purification, synthesis of acetylene, and synthesis and collection of benzene. The changes made to the original design of the synthesis procedures and the operational parameters adopted to optimize the combustion of the plastic materials are described. The measurement of 14C activity was performed using the liquid scintillation counting technique by a QuantulusTM 1220 low-background counter. The δ13C content was compared with the percentage of 14C concentration for the characterization of the bio content in plastic used in the food packaging.

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Determination of Fungi Species Variety in Thermal Phases of Compost Production and Related Operational Parameters

Journal of Environmental Engineering ◽

10.1061/(asce)ee.1943-7870.0001408 ◽

2018 ◽

Vol 144 (8) ◽

pp. 04018065 ◽

Cited By ~ 1

Author(s):

Hassan Hashemi ◽

Fariba Abbasi ◽

Mohammad Reza Samaei ◽

Hossein Khodadadi

Keyword(s):

Operational Parameters

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Selective Determination of Iron(III) in Sea Water by Gold Nanoparticles Self-assembled with N-carboxyl- L-cysteine

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v17i1.274 ◽

2014 ◽

Vol 17 (1) ◽

pp. 001-004 ◽

Cited By ~ 2

Author(s):

Benzhi Liu ◽

Min Wang

Keyword(s):

Gold Nanoparticles ◽

Detection Limit ◽

Sea Water ◽

Stripping Voltammetry ◽

Differential Pulse ◽

Operational Parameters ◽

Selective Determination ◽

Self Assembled ◽

Optimized Conditions

Application of gold nanoparticles self-assembled with N-carboxyl- L-cysteine for the determination of iron(III) was investigated. Differential pulse adsorptive stripping voltammetry was used to detect iron(III). Various operational parameters were investigated and discussed in terms of their effects on the measurement signals. A linear range from 0.1 nM to 1.8 nM with a detection limit of 0.03 nMwas obtained under optimized conditions. The applicability of the method was successfully tested by determination of iron(III) in sea water samples.

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