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Thermospheric neutral wind studies over the equatorial region:A review

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Earth and Planetary Physics 2025年第1期9卷 81-100页

作者： Siti Syazwani Nasuha Idahwati Sarudin Nurul Shazana Abdul Hamid Ahmad Fairuz Omar School of Physics Universiti Sains Malaysia11800 USMPulau PinangMalaysia Department of Applied Physics Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Space Science Centre(ANGKASA) Institute of Climate ChangesUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia

Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several ***,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still *** ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric ***,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain *** address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different *** low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip *** neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the ***,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be *** review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting.

关键词： thermospheric neutral wind thermosphere-ionosphere system dip equator equatorial region

Enhancing Solar Photovoltaic Efficiency:A Computational Fluid Dynamics Analysis

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Energy Engineering 2025年第1期122卷 153-166页

作者： Rahool Rai Fareed HussainMangi Kashif Ahmed Sudhakar Kumaramsay Faculty of Mechanical and Automotive Engineering Universiti Malaysia Pahang Al-Sultan AbdullahPekan26600PahangMalaysia Faculty of Engineering Science&Technology Hamdard UniversityKarachi74600Pakistan Electrical Engineering Department SUKKUR IBA UniversitySukkur65200Pakistan Berlin School of Business and Innovation BSBI Faculty of Computer Science and InformaticsBerlin12043Germany Automotive Engineering Centre University Malaysia Pahang Al Sultan AbdullahPekan26600PahangMalaysia Centre for Research in Advanced Fluid&Processes(Fluid Centre) Universiti Malaysia Pahang Al-Sultan Abdullah(UMPSA)Paya BesarKuantan26300PahangMalaysia

The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable *** energy,among the various renewable sources,is particularly appealing due to its abundant ***,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight *** study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat *** CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of *** specific parameters were found to maximize the heat transfer and temperature reduction *** finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar *** cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits.

关键词： PV module efficiency water film thickness reynolds number CFD analysis PV/T renewable energy

Review on the applications and developments of drag reducing polymer in turbulent pipe flow

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1921-1932页

作者： M.A.Asidin E.Suali T.Jusnukin F.A.Lahin Faculty of Engineering Universiti Malaysia Sabah

Drag reduction phenomenon in pipelines has received lots of attention during the past decades due to its potential engineering applications, especially in fluid transporting industries. Various methods to enhance drag reduction have been developed throughout the years and divided into two categories;non-additives method and additives method. Both categories have different types of methods, with different formulations and applications which will generally be discussed in this review. Among all the methods discussed, drag reduction using polymer additive is as one of the most enticing and desirable methods. It has been the subject of research in this field and has been studied extensively for quite some time. It is due to its ability to reduce drag up to 80% when added in minute concentrations. Reducing drag in the pipe will require less pumping power thus offering economic relieves to the industries. So, this paper will be focusing more on the use of polymer additives as drag reducing agent, the general formulations of the additives, major issues involving the use of drag reducing polymers, and the potential applications of it. However, despite the extensive works of drag reduction polymer, there are still no models that accurately explain the mechanism of drag reduction. More studies needed to be done to have a better understanding of the phenomenon. Therefore, future research areas and potential approaches are proposed for future work.

关键词： Pipe lines Drag reduction Polymer additives Drag reducing agents

Electroless copper-phosphorus coatings with the addition of silicon carbide (SiC) particles

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 615-622页

作者： Soheila Faraji Afidah Abdul Rahim Norita Mohamed Coswald Stephen Sipaut School of Chemical Sciences Universiti Sains Malaysia11800 USMPenangMalaysia School of Engineering and Information Technology Universiti Malaysia Sabah88999 Kota KinabaluSabahMalaysia

Cu-P-silicon carbide （SiC） composite coatings were deposited by means of electroless *** effects of pH values,temperature,and different concentrations of sodium hypophosphite （NaH2PO2·H2O）,nickel sulfate （NiSO4·6H2O）,sodium citrate （C6H5Na3O7·2H2O） and SiC on the deposition rate and coating compositions were evaluated,and the bath formulation for Cu-P-SiC composite coatings was *** coating compositions were determined using energy-dispersive X-ray analysis （EDX）.The corresponding optimal operating parameters for depositing Cu-P-SiC are as follows：pH 9;temperature,90oC;NaH2PO2·H2O concentration,125 g/L;NiSO4·6H2O concentration,3.125 g/L;SiC concentration,5 g/L;and C6H5Na3O7·2H2O concentration,50 g/*** surface morphology of the coatings analysed by scanning electron microscopy （SEM） shows that Cu particles are uniformly *** hardness and wear resistance of Cu-P composite coatings are improved with the addition of SiC particles and increase with the increase of SiC content.

关键词： electroless deposited coating electroless copper plating silicon carbide particles sodium hypophosphite hardness wear resis-tance

Recent development and challenges in enhancing fire performance on wood and wood-based composites:A 10-year review from 2012 to 2021

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Journal of Bioresources and Bioproducts 2024年第1期9卷 27-42页

作者： Charles Michael Albert Kang Chiang Liew Faculty of Tropical Forestry Universiti Malaysia SabahKota Kinabalu 88400Kota KinabaluSabah 88400Malaysia

Due to their durability,versatility,and aesthetic value,wood and wood-based composites are widely used as building *** fact that these materials are flammable,however,raises a major worry since they might cause fire hazards and significant loss of life and *** article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their *** current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this ***,organic chemicals,and densification are some recent developments in fire-retardant treatments that are also *** points from the review are summarized,along with potential areas for further research and development.

关键词： Fire performance Fire-retardant materials Wood Wood-based composite Nanoparticles coating Surface charring Bio-based fire retardant Densification

Heavy metal pollution assessment in marine sediments in the Northwest coast of sabah,malaysia

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China Geology 2023年第4期6卷 580-593页

作者： Sin-Yi Ling Asis Junaidi Abdullah Mohd-Harun Musta Baba Faculty of Science and Natural Resources Universiti Malaysia SabahKota KinabaluSabah 88400Malaysia Small Island Research Center Universiti Malaysia SabahKota KinabaluSabah 88400Malaysia

Heavy metal contents along the Northwest coast of sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average sediment pH(7.82, 9.00 and 8.99), organic matter(0.62%, 1.60%, and 2.27%), moisture content(25.00%, 29.70%, and 15.00%) and sandy texture in Kota Belud, Kudat and Mantanani Island,respectively. The major elements show Ca>Fe>Mg>Al>Mn for all study sites, while the heavy metals show Ni>Cr>Zn>Cu>Co>Pb, Cr>Ni>Zn>Cu>Pb>Co and Zn>Pb>Cr>Ni, for Kota Belud, Kudat and Mantanani Island, respectively. The pollution degree of heavy metals was evaluated by using the Sediment Quality Assessment(SQA). The SQA parameters indicated none to moderate pollution in Kota Belud that shows Class 0, Class 1 and Class 2 pollution. The parameters also indicated none to low pollution in Kudat and Mantanani Island that show only Class 0 pollution. The enrichment factor(EF) suggested minor to moderately severe metal enrichment by anthropogenic sources in Kota Belud, whereas only minor enrichment in Kudat and Mantanani Island. The modified pollution degree(MCD<1.5) and pollution load index(0 PLI<1) indicating only low pollution level in the marine sediments for all study sites. The objectives of this study are:(1) to determine the physico-chemical parameters of sediments,(2) interpret the heavy metal contents and(3) evaluate the sediment quality.

关键词： Physico-chemical properties Sediment quality Major elements Heavy metal pollution Ni-Cr-Zn-Cu-Co-Pb pollution Marine sediment Coastline

Kappaphycus alvarezii waste biomass:A potential biosorbent for chromium ions removal

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Journal of Environmental Sciences 2011年第6期23卷 918-922页

作者： Oon Lee Kang Nazaruddin Ramli Mamot Said Musa Ahmad Suhaimi Md Yasir Arbakariya Ariff School of Chemical Sciences and Food Technology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia School of Sciences and Technology Universiti Malaysia Sabah88400 Kota KinabaluSabahMalaysia Faculty of Biotechnology and Biomolecular Science Universiti Putra Malaysia43400 SerdangSelangorMalaysia

The Cr（III） sorption experiments onto Kappaphycus alvarezii waste biomass were conducted at different pH values（2-6） under the conditions of initial metal concentration of 10-50 mg/L and the chemical compositions of Cr-Cu and *** Cr（III） sorption capacities were slightly dependent on pH,and the maximum sorption capacity was 0.86 mg/g at pH *** sorption capacities increased with increase in the initial metal concentration,whereas it was suppressed by the presence of Cu（II） and Cd（III） in the *** Cr（III） sorption equilibrium was evaluated using Langmuir,Freundlich and BET *** sorption mechanisms were characterised using scanning electron microscopy and Fourier transform infrared *** main mechanisms were ion exchange coupled with a complexation *** alvarezii waste biomass represents a potential for Cr（III） ion removal from aqueous solution.

关键词： biosorption chromium Kappaphycus alvarezii

Gas chromatography-mass spectrometry analysis of various organic extracts of Merremia borneensis from sabah

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Asian Pacific Journal of Tropical Medicine 2011年第8期4卷 637-641页

作者： M Amzad Hossain Muhammad Dawood Shah Mahyar Sakari Biotechnology Research Institute Universiti Malaysia SabahLocked Bag No.207388400 KotakinabaluSabahMalaysia School of Science and Technology Universiti Malaysia SabahLocked Bag No.207388400 KotakinabaluSabahMalaysia

Objective:To analyse the chemical composition of different extracts of Merremia borneensis(M. borneensis) by gas chromatography-mass spectrometry(GC-MS).Methods:The dried leaves powder was extracted with methanol at room temperature by using Soxhlet *** crude extracts of *** were extrastel with hexane,chloroform,ethyl acetate and butanol. Results:Qualitative analyses of various organic crude extracts showed that majority of these are flavonoids,terpeniods,alkaloids and *** of the identified compounds by GCMS are biologically *** the *** leaf possesses certain characteristics that can be ascribed to cultivation on a domestic ***:The suitable extracts for respective compounds can be chosen on the basis of above GC-MS *** the major compounds from different extracts are biologically active *** the identification of a good number of compounds from various extracts *** might have some ecological significance.

关键词： Merremia borneensis Organic extracts Qualilalive analysis GC-MS

Modified 2 Satisfiability Reverse Analysis Method via Logical Permutation Operator

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Computers, Materials & Continua 2023年第2期74卷 2853-2870页

作者： Siti Zulaikha Mohd Jamaludin MohdAsyraf Mansor Aslina Baharum Mohd Shareduwan Mohd Kasihmuddin Habibah A.Wahab Muhammad Fadhil Marsani School of Mathematical Sciences Universiti Sains MalaysiaMindenPenang11800Malaysia School of Distance Education Universiti Sains MalaysiaMindenPenang11800Malaysia Faculty of Computing and Informatics Universiti Malaysia SabahJalan UMSKota Kinabalu88450SabahMalaysia School of Pharmaceutical Sciences Universiti Sains MalaysiaMindenPenang11800Malaysia

The effectiveness of the logic mining approach is strongly correlated to the quality of the induced logical representation that represent the behaviour of the ***,the optimum induced logical representation indicates the capability of the logic mining approach in generalizing the real datasets of different variants and *** main issues with the logic extracted by the standard logic mining techniques are lack of interpretability and the weakness in terms of the structural and arrangement of the 2 Satisfiability logic causing lower *** address the issues,the logical permutation serves as an alternative mechanism that can enhance the probability of the 2 Satisfiability logical rule becoming true by utilizing the definitive finite arrangement of *** work aims to examine and analyze the significant effect of logical permutation on the performance of data extraction ability of the logic mining approach incorporated with the recurrent discrete Hopfield Neural *** on the theory,the effect of permutation and associate memories in recurrent Hopfield Neural Network will potentially improve the accuracy of the existing logic mining *** validate the impact of the logical permutation on the retrieval phase of the logic mining model,the proposed work is experimentally tested on a different class of the benchmark real datasets ranging from the multivariate and timeseries *** experimental results show the significant improvement in the proposed logical permutation-based logic mining according to the domains such as compatibility,accuracy,and competitiveness as opposed to the plethora of standard 2 Satisfiability Reverse Analysis methods.

关键词： Logic mining logical permutation discrete hopfield neural network knowledge extraction