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A Pioneering Approach to the Synthesis of Silver Nanoparticles

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Journal of.m.terials Science and Chemical Engineering 2024年第7期12卷 14-22页

作者： Wasan A. al-Dulaimi Zeena m. al-Azzawi Emad K. al-Shakarchi Physics Department College of Science Al-Nahrain University Baghdad Iraq

Our research introduces a groundbreaking chemical reduction method for synthesizing silver nanoparticles, marking a significant advancement in the field. The nanoparticles were meticulously characterized using various techniques, including optical analysis, structural analysis, transmission electron microscopy (TEm), and field-emission scanning electron microscope (fESEm). This thorough process instills confidence in the accuracy of our findings. The results unveiled that the silver nanoparticles had a diameter of less than 20 nm, a finding of great importance. The absorption spectrum decreased in the peak wavelength range (405 - 394 mm) with increasing concentrations of Ag nanoparticles in the range (1 - 5%). The XRD results indicated a cubic crystal structure for silver nanoparticles with the lattice constant (a = 4.0855 Å), and miller indices were (111), (002), (002), and (113). The simulation on the XRD pattern showed a face center cubic phase with space group fm-3m, providing valuable insights into the structure of the nanoparticles.

关键词： Chemical Reduction method UV-VIS Absorption Spectrometer field-Emission Scanning Electron microscope (fESEm) Transmission Electron microscopy (TEm)

Carbon monoxide as C1 Building Block in fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.f.Calvete Gabor mikle Laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide fine chemicals Carbonylation Hydroformylation C-H functionalization

Recent progress in two-dimensional metallenes and their potential application as electrocatalyst

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Journal of Energy Chemistry 2024年第7期94卷 577-598页

作者： Umer Shahzad mohsin Saeed muhammad fazle Rabbee Hadi m.marwani Jehan Y.al-Humaidi muhammad altaf Raed H.althomali Kwang-Hyun Baek md.Rabiul Awual mohammed m.Rahman Department of Chemistry Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Biotechnology Yeungnam UniversityGyeongsanSouth Korea Center of Excellence for Advanced materials Research(CEAmR) King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Chemistry College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.BOX 84428Riyadh 11671Saudi Arabia Department of Chemistry Center of Excellence for Innovation in Chemistry(PERCH-CIC)Center of Excellence in Materials Science and TechnologyFaculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand Department of Chemistry College of Art and SciencePrince Sattam Bin Abdulaziz UniversityWadi Al-Dawasir 11991Saudi Arabia Western Australian School of.m.nes:minerals Energy and Chemical EngineeringCurtin UniversityGPO Box U 1987PerthWA 6845Australia

In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis *** is one area where their exceptional physicochemical and electrical characteristics might be *** are unique because they include several metal atoms that are not in a coordinated *** makes them more active and improves their atomic uti-lization,which in turn increases their catalytic *** article delves into the potential of two-dimensional metals as electrocatalysts for carbon dioxide reduction,fuel oxidation,oxygen evolution,and oxygen reduction reactions in the context of sustainable energy *** to the exception-ally high surface-to-volume ratio,large surface area as well as their optimized atomic use efficiency,2D materials defined by atomic layers are crucial for surface-related sustainable energy *** to its exceptional properties,such as high conductivity and the ability to enhance the exposure of active metal sites,2D metallenes have recently attracted a lot of interest for use in catalysis,electronics,and energy-related *** their highly mobility,adjustable surface states,and electrical struc-tures that can be fine-tuned,2D metallenes are promising nanostructure materials for use in energy con-version with the sustainable applications.

关键词： metallenes Electrocatalysts Electrochemical processes Atomically thin structure

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Coronary Artery Patterns in Diabetic Patients Undergoing Diagnostic Coronary Angiography-Data from a major Cardiac Center in Yemen

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World Journal of Cardiovascular Diseases 2024年第4期14卷 268-281页

作者： mohammed m. al-Kebsi Yehia al-Ezzy Amatasamad al-Tanobi Ayman A. mohammed Department of Cardiology Faculty of Medicine and Health Sciences Sana&#8217a University Sana&#8217a Yemen Cardiac Center Al-Thawra Modern General Hospital Sana&#8217a Yemen

Background: Diabetes mellitus (Dm) is independently associated with an increased risk of cardiovascular mortality and morbidity, including coronary artery disease (CAD). CAD is a shared burden disease and the leading cause of death in developed and developing countries. We aimed to assess the angiographic patterns of coronary arteries in patients with Dm in a developing country (Yemen) as the first study. methods: This study is a cross-sectional, prospective, observational study that includes a total of 250 patients who were admitted for elective diagnostic coronary angiography. Results: 96 (38.4%) patients were diabetics;68% were male;mean age was 57 ± 11 years. The incidence of three-vessel disease was 31.2% of patients. Considering the severity of lumen occlusion, (11.2%) of patients had non-significant lesions, (37.6%) of patients had significant lesions, and (32%) had total occlusive lesions. Lesions were of LAD in 76%, RCA in 60%, and LCX in 52% of the population. Among diabetics, two and 3-vessel diseases (33.3% vs. 20.8% & 50% vs. 19.5%, P = 0.001), left main lesion (10.4% vs. 2.6%, P = 0.012), significant stenosis (41.7% vs. 35.1%, P = 0.032), total occlusion of coronary arteries (43.8% vs. 19.5%, P = 0.032) and type C lesion (66.7% vs. 35.1%, P = 0.010) were more frequent than non-Dm patients. Conclusion: The burden of significant and severe coronary lesions is more common among Dm, which may be the major cause of.m.rbidity and mortality of Dm in developing countries.

关键词： Diabetes mellitus Coronary Artery Diseases Coronary Angiography

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.m.Gillies E.Spanswick E.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

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Experimental and numerical study of effecting core configurations on the static and dynamic behavior of honeycomb plate with aluminum material

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Defence Technology（防务技术） 2024年第9期39卷 177-192页

作者： Nehad Abid allah Hamza fatima mohammed K.al-fatlwe muna ali Talib Engineering College Al-Qasim Green University51013BabylonIraq Engineering Technical College of al-Najaf Al-Furat Al-Awsat Technical University(ATU)Najaf54003Iraq

The sandwich panel incorporated a honeycomb core,a widely utilized composite structure recognized as a fundamental classification of composite *** a core resembling a honeycomb,possessing thickness and softness,and is flank by rigid face sheets that sandwich various shapes and *** paper presents an examination of the static and dynamic analysis of lightweight plates made of aluminum honeycomb sandwich *** sandwich plate samples are 300 mm long,and 300 mm wide,the heights of the core have been varied at four values ranging from 10 to 25 *** honeycomb core is manufactured from aluminum material by using a novel technique namely resistance spot welding(RSW)instead of using adhesive material,which is often used when an industrial flaw is *** optimization based on response surface methodology(RSm)and design of experiment software(DOE)was used to verify the current work.A theoretical examination of the crashworthiness behavior(maximum bending load,maximum deflection)and vibration attributes(natural frequency,damping ratio,transient temporal response)of honeycomb sandwich panels with different design parameters was also carried *** addition,the finite element method-based ANSYS software was used to confirm the theoretical *** findings of the present work showed that the relationship between the natural frequency,core height,and cell size is *** contrast,the relationship between the natural frequency and the thickness of the cell wall is ***,the damping ratio is inversely proportional to the core height and cell size but directly proportional to the thickness of the cell *** study indicates that altering the core height within 10-25 mm leads to a significant increase of 82%in the natural frequency and a notable decrease of 49%in the damping *** findings are based on a specific cell size value of 0.01 m and a cell wall thickness of 0.001 ***,the results indicate

关键词： Honeycomb Load Transient response free vibration Natural frequency

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A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.f.Darwish mohamed H.A.Hassan Nagat m.K.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturefted especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by fourier transform infrared(fTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the fTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDf)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila m.Halman mohammed J.f.alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and *** this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human *** can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or *** this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS *** then evaluate the accuracy and performance of the proposed TBDC *** technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

Corrosion and Scaling Threat in Upstream Oil Operation

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World Journal of Engineering and Technology 2024年第2期12卷 426-437页

作者： Nasir Ullattumpoyil Talal m. al-Ghamdi Nasser R. al-Hajri Southern Area Technical Support Department Saudi Aramco Dhahran KSA

Corrosiveness or scaling is an inherent threat to oil operations. The primary cause for this threat is the presence of water having complex geochemical matrix. Unanticipated water production, particularly if it contains unwanted impurities, can significantly impact hydrocarbon production. The current paper discusses the degree of threat posed to oil operation facilities based on the water characteristics. methodology involved the collection and analysis of water samples from major sources in oil industry such as groundwater, wellheads and seawater. The parameters tested include geochemical, microbiological and pollutants. The lab data was used to develop scaling and corrosion prediction indices such as Langelier Saturation Index (LSI), Ryznar Stability Index (RSI) and Puckorius Scaling Index (PSI). The study indicated varying water chemistry for different sources. mixing of those waters may lead to ionic saturation and scaling in different facilities. Presence of the SRB and GAB in some water sources also posed threat to water system by forming fouling and corrosion. Seawater used for offshore oilfields water injection to maintain reservoir pressure and improve oil recovery showed scaling tendency, whereas under different reservoir pressure, it can cause corrosion. Some of the samples also had corrosion residuals such as iron, which indicated active corrosion. Current study showed higher alkalinity with high sulfate for one groundwater sample with presence of active corrosion residuals such as dissolved iron and manganese. The study showed positive value for LSI which indicated supersaturation of the water samples with respect to calcium carbonate (CaCO3) and scale forming. Similarly, for RSI and PSI, the value was below six which confirmed the scaling potential for all the samples. Even though the index value was pointing towards scaling potential, the geochemistry, microbiology and presence of other impurities indicated corrosion threat to the oil and g

关键词： formation Water Petroleum Reservoirs Groundwater Saturation Indices Corrosiveness