UV-Visible Spectrophotometer for Distinguishing Oxidation Time of Engine Oil

Torrey Holland; Ali Mazin Abdul-Munaim; Christopher Mandrell; Robinson Karunanithy; Dennis G. Watson; Poopalasingam Sivakumar

doi:10.3390/lubricants9040037

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Publication Date

Sat Apr 03 2021

Journal Name

Lubricants

Volume

9

DOI

10.3390/lubricants9040037

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UV-Visible Spectrophotometer for Distinguishing Oxidation Time of Engine Oil

UV-Vis

thermal oxidation

engine oil

oil life

linear regression

Torrey Holland

Ali Mazin Abdul-Munaim

Christopher Mandrell

Robinson Karunanithy

Dennis G. Watson

Poopalasingam Sivakumar

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Samples of gasoline engine oil (SAE 5W20) that had been exposed to various oxidation times were inspected with a UV-Visible (UV-Vis) spectrophotometer to select the best wavelengths and wavelength ranges for distinguishing oxidation times. Engine oil samples were subjected to different thermal oxidation periods of 0, 24, 48, 72, 96, 120, and 144 hours, resulting in a range of total base number (TBN) levels. Each wavelength (190.5 – 849.5 nm) and selected wavelength ranges were evaluated to determine the wavelength or wavelength ranges that could best distinguish among all oxidation times. The best wavelengths and wavelength ranges were analyzed with linear regression to determine the best wavelength or range to predict oxidation time.

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Publication Date

Tue May 01 2018

Journal Name

Journal Of Physics: Conference Series

Synthesis, Characterization and the Corrosion Inhibition Study of Two Schiff Base Ligands Derived From Urea and Thiourea and Their Complexes with Cu(II) and Hg(II) Ions

Alwan W.

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Publication Date

Thu Mar 03 2022

Journal Name

Archives Of Rheumatology

Association of tumor necrosis factor-alpha promoter region gene polymorphism at positions -308G/A, -857C/T, and -863C/A with etanercept response in Iraqi rheumatoid arthritis patients

Samer Imad

Munaf

Faiq

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Objectives: This study aims to evaluate the association between polymorphisms in the promoter region of the tumor necrosis factor-alpha (TNF-α) gene at locations -308G/A, -857C/T, and -863C/A with the tendency of being non-responder to etanercept.

Patients and methods: Between October 2020 and August 2021, a total of 80 patients (10 males, 70 females; mean age: 50 years; range, 30 to 72 years) with rheumatoid arthritis (RA) receiving etanercept for at least six months were included. The patients were divided into two groups responders and non-responders, based on their response after six months of continuous treatment. Following polymerase chain reac

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Publication Date

Sat Dec 20 2025

Journal Name

Bmc Musculoskeletal Disorders

Effects of acute static stretching and dynamic warm-up protocols on shoulder function in young adult male athletes with shoulder impingement syndrome: a randomized controlled crossover trial

Mohammad

Maryam Abduljabbar

Mohammed

Fereshteh

Mojtaba

Mohammad

Nicola

Ali Shamsi

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Publication Date

Fri Jan 30 2026

Journal Name

Academic Science Journal

the Synthesis and characterization of (E)-5-((2-hydroxynaohthalen-1-yl) diazenyl))-2,3-dihydrophthalazine-1,4-dione complexes with Some Metal ions and their industrial and biological applications

Amer J.

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Publication Date

Thu Jan 01 2026

Journal Name

Aip Conference Proceedings

Synthesis and characterization of Co(II),Ni(II),Cu(II) and Zn(II) complexes with 2-(4-chlorophenyl)diazenyl)-3,5-dimethylphenol and their industrial and biological applications

Hanaa Hussein

Amer J.

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Publication Date

Mon Jun 15 2026

Journal Name

Iklil For Humanity Studies

STYLISTIC FEATURES OF MITIGATING EXPRESSIONS IN RUSSIAN FEMALE SPEECH (BASED ON MATERIAL FROM THE RUSSIAN PRESS)السمات الاسلوبية لعبارات التلطف في الخطاب النسوي الروسي (الصحافة الروسية انموذجا)

Stylistics

media discourse

press

pragmatics

politeness

softening.

Нсрин

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This study analyzes the stylistic features of euphemisms in feminist discourse, based on material from the contemporary Russian press of the period (2015–2025). The central issue lies in how the linguistic devices used to soften the harshness and confrontation in discourse contribute to shaping a distinct feminine communicative style within media discourse, where the context necessitates combining the expression of the author\\'s position with maintaining a harmonious interaction with the wider audience. This study aims to uncover and classify the stylistic mechanisms of euphemism at the lexical-grammatical, syntactic, and pragmatic levels, as well as to determine its role in constructing gendered linguistic behavior. The research finding

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Publication Date

Fri Sep 18 2026

Journal Name

Cell Biochemistry And Biophysics

Orange Peel-Mediated Co-formation of a ZnO–Calcite Mixed-Phase Nanostructured Material: Physicochemical Characterization and Preliminary In vitro Antioxidant, α-Glucosidase Inhibitory, and Differential Cytotoxicity Assessment

Nada Nadhim

Najlaa Qassim

Wessal M.

Hiba Jumaa

Ghufran Kadhim

Yasser M.

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Orange peel was used as a plant-derived medium to prepare a ZnO–calcite mixed-phase nanostructured material, which was physicochemically characterized and evaluated for DPPH radical-scavenging, α-glucosidase inhibitory, and in vitro cytotoxic activities. XRD confirmed the coexistence of hexagonal wurtzite ZnO and crystalline calcite, with ZnO apparent crystallite sizes ranging from 9.2 to 28.3 nm (mean 16.4 ± 7.3 nm). FTIR identified Zn–O vibrations, carbonate-related bands, surface hydroxyl groups, and residual organic functionalities, while FESEM revealed irregular agglomerates composed of nanoscale grains. EDX showed Zn, O, C, and Ca as the principal elements, and the material exhibited a zeta potential of -14.86 ± 0.52 mV

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Publication Date

Sun Feb 01 2015

Journal Name

Journal Of Economics And Administrative Sciences

Climate change and dust storms in Iraq / 'Baghdad', case study

الغبار العالق - الغبار المتصاعد -العاصفة الغبارية -التغير المناخي -القيم المفقودة - القيم الشاذة المتعددة - نماذج انحدار

Suspended dust

rising dust

dust storm

climate change

missing values

multiple outliers

regression models

فاطمة جاسم

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A dust storm in Iraq is a climatic phenomenon common in arid and semi-arid regions . The frequency of the occurrence has increased drastically in the last decade and it is increasing continuously .Baghdad city like the rest of Iraq is suffering from the significant increase in dust storms . In this research , the study of the phenomenon of dust storms for all types (Suspended dust , rising dust , dust storm) , and its relationship with some climate variables (Temperature , rainfall ,wind speed) .The statement of the impact of climate change on this phenomenon to Baghdad station for the period (1981 – 2012) . Time series has been addressing the phenomenon of storms and cli

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Publication Date

Sat Sep 01 2018

Journal Name

Polyhedron

Novel dichloro (bis {2-[1-(4-methylphenyl)-1H-1, 2, 3-triazol-4-yl-κN3] pyridine-κN}) metal (II) coordination compounds of seven transition metals (Mn, Fe, Co, Ni, Cu, Zn and Cd)

The 1

3-dipolar cycloaddition “click” reaction between an azide and an alkyne to give a 1

2

3-triazole was reported by Huisgen in 1961 [1]. In 2002 the Copper(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAC) to prepare a 1

2

3-triazole was reported [2]

[3]. The existence of relatively basic nitrogen atoms in the 1

2

3-triazole rings

and the possibility of introducing additional donor groups in the substituents (Fig. 1)

made the CuAAC “click” reaction an attractive method to prepare differently substituted 1

2

3-triazoles. These compounds have been used as ligands to coordinate to various metal ions that display a range of applications such as in electrochemical and photochemical studies

in supramolecular chemistry

magnetism

metal-ion sensing and catalysis [4]. The reasons for the success of the “click” reaction

is that it is easy to carry out and is widely applicable. It is not affected by a variety of functional groups

and can be carried out with a variety of Cu(I) catalysts and solvents

including aqueous conditions. The Cu(I) catalysts overcome the high activation energy barrier of the non-catalyzed Huisgen reaction by changing the mechanism of the reaction. A large variety of copper catalysts can be used for the CuAAC reaction

on condition that the maximum concentration of Cu(I) species is generated during the reaction. The pre-catalyst can be a Cu(II) salt (usually CuSO4) together with a reducing agent (often sodium ascorbate) or a Cu(I) compound in the presence of a base or amine ligand and a reducing agent to prevent oxidation to Cu(II). Some strong oxidising cupric salts or complexes such as Cu(OAc)2 also work. The solvent is very flexible from organic to aqueous

with the most commonly used combination water + an alcohol (t-BuOH

MeOH or EtOH). The key role of the solvent or solvent mixture is to solubilize the substrates and Cu(I) catalyst in order to ensure rapid reactions. Such aqueous conditions are very useful for biochemical conjugations

as well as for organic syntheses. We recently reported on the synthesis of a series of differently substituted 1

2

3-triazole chromophores

the substituted 2-(1-phenyl-1H-1

2

3-triazol-4-yl)pyridine ligands [5]

see Fig. 2 middle

with substituents R = H (L1)

CH3 (L2)

OCH3 (L3)

COOH

F

Cl

CN

CF3

O(CH2)3CH3 and N(CH3)2. These versatile ligands were found to coordinate to various first row transition metals

such as manganese

cobalt and nickel [6]. Here we extend the series to include more first row transition metal(II) coordination compounds

iron

copper and zinc

as well as a second row transition metal(II) coordination compound

cadmium

containing the 2-(1-(4-methyl-phenyl)-1H-1

2

3-triazol-1-yl)pyridine chromophore (Fig. 2 right with R = CH3). This series of seven novel coordination compounds is the first series of pyridyl-triazole based transition metal coordination compounds where seven different transition metals are coordinated to the same 1

2

3-triazole chromophore

namely 2-(1-(4-methyl-phenyl)-1H-1

2

3-triazol-1-yl)pyridine.

Kinaan M

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Publication Date

Sat Oct 01 2022

Journal Name

Lark Journal

The problem of synonyms and similar words in the translation of the Holy Quran into Russian (based on the translation by Elmir Kuliev) اشكالية الترادف والكلمات المتقاربة في المعنى في ترجمة القران الكريم الى اللغة الروسية (بناءا على ترجمة إلمير كولييف) Проблема синонимов и близких по значению слов в переводе Священного Корана на русский язык (на материале перевода Эльмира Кулиева)

Tandem

Holy Quran

verse

surah

Translation.

Ashwaq Mohammed

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In our research, we dealt with one of the most important issues of linguistic studies of the Holy Qur’an, which is the words that are close in meaning, which some believe are synonyms, but in the Arabic language they are not considered synonyms because there are subtle differences between them. Synonyms in the Arabic language are very few, rather rare, and in the Holy Qur’an they are completely non-existent. And how were these words, close in meaning, translated in the translation of the Holy Qur’an by Almir Kuliev into the Russian language.

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