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Synthesis and Spectral Properties of 4-（2,5-Dimethoxyphenyl- methelene）-2-phenyl-5-oxazolone （DMPO）

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Chinese Journal of Chemistry 2012年第3期30卷 563-569页

作者： EI-Daly, Samy A Asiri, a.dullah M Alamry, Khalid A hussein, Mahmoud A Chemistry Department Faculty of Science King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia The Center of Excellence for Advanced Materials King Abdulaziz University Jeddah 21589 P.O. Box 80203 Saudi Arabia Department of Chemistry Faculty of Science Tanta University 31527 Tanta Egypt Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt

An interesting flourophore, 4-（2,5-dimethoxyphenylmethelene）-2-phenyl-5-oxazolone （DMPO） was synthesized by mixing an equivalent molar quantity of hippuric acid and 2,5-dimethoxybenzaldehyde in acetic anhydride in the presence of anhydrous sodium acetate. The absorption and fluorescence characteristics of 4-（2,5-dimethoxy-phenyl- methelene）-2-phenyl-5-oxazolone （DMPO） were investigated in different solvents. DMPO dye exhibits red shift in both absorption and emission spectra as solvent polarity increases, indicating change in the dipole moment of mole- cules upon excitation due to an intramolecular charge transfer interaction. The fluorescence quantum yield depends strongly on the properties of the solvents, which was attributed to positive and negative solvatokinetic effects. A crystalline solid of DMPO gave strong excimer like emission at 630 nm due to the excitation of molecular aggregates. This is expected from the idealized crystal structure of the dye that belongs to the B-type class of Steven＇s Classifica- tion. DMPO displayed fluorescence quenching by triethylamine via nonemissive exciplex formation.

关键词： 4-(2,5-dimethoxy-phenylmethelene)-2-phenyl-5-oxazolone (DMPO) effect of medium fluorescencequantum yield solid state emission

Denoising different types of acoustic partial discharge signals using power spectral subtraction

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High Voltage 2018年第1期3卷 44-50页

作者： ramy hussein Khaled Bashir Shaban Ayman H.El-Hag Department of Electrical and Computer Engineering University of British ColumbiaVancouverBCCanada Department of Computer Science and Engineering Qatar UniversityDohaQatar Department of Electrical Engineering American University of SharjahSharjahUAE

Measuring acoustic emission(AE)of partial discharge(PD)phenomena can be adopted to estimate the condition of power ***,the environmental noise encountered with AE of PD measurements negatively affects the accuracy of PD localisation and ***,efficient signal denoising techniques are required for noise suppression and hence,better detection *** study deals with white noise and it is a continuation of a previously published work that deals with random *** published work addresses the random noise suppression using a method named,power spectral subtraction denoising(PSSD).This study applies PSSD to the PD signals contaminated with white noise and uses a novel scheme of noise power spectrum density *** types of AE signals are examined including signals produced by corona,surface,parallel,and void *** and real data demonstrate the superiority of the proposed method over the wavelet shrinkage denoising method as it can more effectively eliminate white noise and preserve signals of low signal-to-noise ratio.

关键词： power noise spectral

Evaluation of Shell and Tube Heat Exchanger Performance by Using ZnO/Water Nanofluids

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Journal of Harbin Institute of Technology(New Series) 2023年第6期30卷 62-69页

作者： hussein Hayder Mohammed Ali Adnan M hussein Kadum Mohammed Hussain Allami Barhm Mohamad Technical Engineering College/Kirkuk Northern Technical UniversityKirkuk 36001Iraq Computer Engineering Techniques Department Al-Kitab UniversityKirkuk 36001Iraq Department of Petroleum Technology Koya Technical InstituteErbil Polytechnic UniversityErbil 44001Iraq

To examine and investigate the impact of nanofluid on heat exchanger performance,including the total heat transfer,the effect of friction factor,the average Nusselt number,and the thermal efficiency,the output heat transfers of a shell and tube heat exchanger using ZnO nanoparticles suspended in water has been conducted *** governing equations were solved using finite volume techniques and CFD simulations with ANSYS/FLUENT Solver *** nanoparticles volume fractions adopted are 0.2%and 0.35%that used in numerical computations under 200 to 1400 Reynolds numbers *** increasing of temperature is approximately 13%from the bottom to the top of heat exchanger,while the maximum enhancement of Nusselt number is about 10%,19%for volume fractions 0.2%and 0.35%*** elevated values of the friction factor at the volumetric ratios of 0.2%and 0.35%are 0.25%and 0.47%*** findings demonstrate that the performance efficiency of shell and tube heat exchanger is enhanced due to the increase in Nusselt number.

关键词： CFD Reynold number thermal efficiency Nusselt number nanofluid heat exchanger

Preparation and Properties of Poly(vinyl alcohol)/Chitosan Blend Bio-nanocomposites Reinforced by Cellulose Nanocrystals

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Chinese Journal of Polymer Science 2014年第12期32卷 1620-1627页

作者： Susan Azizi Mansor Bin Ahmad Nor Azowa Ibrahim Mohd Zobir hussein Farideh Namvar Department of Chemistry Faculty of Science University Putra Malaysia Materials Synthesis and Characterization Laboratory Institute of Advanced Technology University Putra Malaysia Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia Mashhad Branch Islamic Azad University

The aim of this paper is to report the effect of the addition of cellulose nanocrystals（CNCs） on the mechanical, thermal and barrier properties of poly（vinyl alcohol）/chitosan（PVA/Cs） bio-nanocomposites films prepared through the solvent casting process. The characterizations of PVA/Cs/CNCs films were carried out in terms of X-ray diffraction（XRD）, transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, thermogravimetric analysis（TGA and DTG）, oxygen transmission rate（OTR）, and tensile tests. TEM and SEM results showed that at low loading levels, CNCs were dispersed homogenously in the PVA/Cs matrix. The tensile strength and modulus in films increased from 55.1 MPa to 98.4 MPa and from 395 MPa to 690 MPa respectively, when CNCs content went from 0 wt% to 1.0 wt%. The thermal stability and oxygen barrier properties of PVA/Cs matrix were best enhanced at 1.0 wt% of CNCs loading. The enhanced properties attained by incorporating CNCs can be beneficial in various applications.

关键词： Bio-nanocomposite Poly(vinyl alcohol)/chitosan Cellulose nanocrystals Mechanical properties Thermal properties.

On chaotic properties of new semidynamical systems of Lasota type in two spaces

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International Journal of Biomathematics 2018年第5期11卷 201-215页

作者： Habeeb Kareem a.dullah Amal Khalaf Haydar Yaqoob All hussein Department of Mathematics Faculty of Education for Girls University of Kufa Najaf Iraq

The present study is concerned with construct two new semidynamical systems which are generated by two partial differential equations of Lasota type. In addition, this study discusses the asymptotic properties： Strong stability, exponential stability, periodic points, the density of periodic points, transitivity and chaos in two spaces： Lp space and Lp space.

关键词： Initial value problems for linear first-order equations stability periodic solutions chaotic dynamics.

Review:Solar Still with Additional Condenser

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Journal of Harbin Institute of Technology(New Series) 2023年第3期30卷 60-67页

作者： Azad A.hussein Najim Abid Jassim Mechanical Engineering Department Engineering CollegeUniversity of BaghdadBaghdad 10011Iraq

Getting consumable water to individuals has been a continuous challenge *** or non⁃purified water sources are responsible for the bulk of human *** demand for water purification that does not harm the biological system is ***⁃based desalination is one of the effective water purification methods creating ultra⁃pure refined ***⁃based still refining frameworks offer maintainable devices for a freshwater *** plans were tried by analysts to move forward the efficiency of sun⁃powered *** to the experiments,solar still coordinates outside or inside the condenser is considered to be a valid and successful *** survey hopes to show,explain,and study the performance of several solar stills combined with diverse condenser designs.

关键词： solar still desalination condenser renewable energy distillate yield

Cycling of antibiotics for the prophylaxis of recurrent spontaneous bacterial peritonitis in a cirrhotic patient

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World Journal of Gastroenterology 2005年第41期11卷 6407-6408页

作者： N Assy S Schlesinger D Miron O hussein Department of Internal Medicine A Sieff Government Hospital SafedIsraelTechnion InstituteHaifaIsrael

More than 80% of cirrhotic patients who have been treated successfully for spontaneous bacterial peritonitis （SBP） experience a recurrence. Long-term prophylaxis with single daily oral antibiotic has been shown to be cost effective in delaying a recurrence but only for a short time. What has never been tested in this population is the cycling of antibiotics. We report the beneficial use of antibiotic cycling for 36 weeks in a 74-year-old woman with cryptogenic cirrhosis and recurrent SBE

关键词： Aged Anti-Bacterial Agents dosage Bacterial Infections control Female Humans Liver Cirrhosis Peritonitis Recurrence

PCSK9 and triglyceride-rich lipoprotein metabolism

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The Journal of Biomedical Research 2015年第6期29卷 429-436页

作者： Irena Druce hussein Abujrad Teik Chye Ooi Clinical Research Laboratory Division of Endocrinology and MetabolismDepartment of MedicineUniversity of Ottawa Chronic Disease Program Ottawa Hospital Research InstituteThe Ottawa Hospital

Pro-protein convertase subtilisin-kexin 9 （PCSK9） is known to affect low-density lipoprotein （LDL） metabolism, but there are indications from several lines of research that it may also influence the metabolism of other lipopro- teins, especially triglyceride-rich lipoproteins （TRL）. This review summarizes the current data on this possible role of PCSK9. A link between PCSK9 and TRL has been suggested through the demonstration of （1） a correlation between plasma PCSK9 and triglyceride （TG） levels in health and disease, （2） a correlation between plasma PCSK9 and markers of carbohydrate metabolism, which is closely related to TG metabolism, （3） an effect of TG-lowering fibrate therapy on plasma PCSK9 levels, （4） an effect of PCSK9 on postprandial lipemia, （5） an effect of PCSK9 on adipose tissue biology, （6） an effect of PCSK9 on apolipoprotein B production from the liver and intestines, （7） an effect of PCSK9 on receptors other than low density lipoprotein receptor （LDLR） that are involved in TRL metabolism, and （8） an effect of anti-PCSK9 therapy on serum TG levels. The underlying mechanisms are unclear but starting to emerge.

关键词： hyperlipidemia hypercholesterolemia molecular biology

Embedding-based Detection and Extraction of Research Topics from Academic Documents Using Deep Clustering

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Journal of Data and Information Science 2021年第3期6卷 99-122页

作者： Sahand Vahidnia Alireza Abbasi hussein A.Abbass University of New South Wales Canberra2612ACTAustralia

Purpose:Detection of research fields or topics and understanding the dynamics help the scientific community in their decisions regarding the establishment of scientific *** also helps in having a better collaboration with governments and *** study aims to investigate the development of research fields over time,translating it into a topic detection ***/methodology/approach:To achieve the objectives,we propose a modified deep clustering method to detect research trends from the abstracts and titles of academic *** embedding approaches are utilized to transform documents into vector-based *** proposed method is evaluated by comparing it with a combination of different embedding and clustering approaches and the classical topic modeling algorithms(***)against a benchmark dataset.A case study is also conducted exploring the evolution of Artificial Intelligence(AI)detecting the research topics or sub-fields in related AI ***:Evaluating the performance of the proposed method using clustering performance indicators reflects that our proposed method outperforms similar approaches against the benchmark *** the proposed method,we also show how the topics have evolved in the period of the recent 30 years,taking advantage of a keyword extraction method for cluster tagging and labeling,demonstrating the context of the *** limitations:We noticed that it is not possible to generalize one solution for all downstream ***,it is required to fine-tune or optimize the solutions for each task and even *** addition,interpretation of cluster labels can be subjective and vary based on the readers’*** is also very difficult to evaluate the labeling techniques,rendering the explanation of the clusters further *** implications:As demonstrated in the case study,we show that in a real-world example,how the proposed method would enable the researchers and

关键词： Dynamics of science Science mapping Document clustering Artificial intelligence Deep learning