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Materials Sciences and Applications 2013年第1期4卷 52-62页

作者： Lilis Hermida Ahmad Zuhairi abdullah abdul rahman Mohamed School of Chemical Engineering Universiti Sains Malaysia Penang Malaysia

This work investigated the possibility of incorporation of nickel into several mesostructured cellular foam (MCF) silica supports prepared at various aging times (1, 2, and 3 days) by using deposition-precipitation method followed by reducetion process and to look for the best support to obtain supported nickel catalyst with highest nickel loading and smallest size of nickel nanoparticles. Analyses using nitrogen adsorption-desorption, transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) showed that MCF silica prepared at aging time of 3 days was the best support as the corresponding nickel functionalized MCF catalyst had the highest nickel content (17.57 wt%) and the smallest size of nickel nanoparticles (1 - 2 nm) together with high porosity (window pore size of 90A). The result was attributed to the highest window pore size in the MCF support which allowed more nickel nanoparticles to be incorporated.

关键词： Mesostructured Cellular Foam Amorphous Materials Nanostructures Sol-Gel Growth Surface Properties

Mechanical and superconducting properties of nanosize MgO added dip-coated Bi2Sr2CaCu2O8superconducting tape

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Natural Science 2011年第6期3卷 484-487页

作者： Nasri A Hamid Mohd Yusri Abd rahman noor Fairuz Shamsudin Department of Engineering Sciences & Mathematics College of Engineering Universiti Tenaga Nasional Kajang Selangor Malaysia

In this work, 3% to 8% (in weight) of nanosize MgO particles was added to Bi2Sr2CaCu2O8 (Bi- 2212) high-temperature superconductor to fab-ricate Bi-2212 superconducting material with superior mechanical properties. The mechanical strength of the samples was studied by con-ducting the compression test at room tempera-ture, and the addition of 5% nanosize MgO par-ticles produced the highest strength when com- pared with other samples. The sample with 5% MgO addition also exhibited superior super-conducting properties. The Bi-2212 powder with 5% nanosize MgO addition was used to fabricate Bi-2212 tapes through the dip-coating-then- stacking method. The fully processed tapes were investigated via dc electrical resistance measurements, XRD patterns, SEM micrographs, transport critical current density and tensile tests. The tensile tests were conducted at room and cryogenic (77 K) temperatures. Results of tensile tests and Young’s modulus for the tapes showed that the Bi-2212 tapes with nanosize MgO addition recorded better mechanical prop-erty compared to the non-added samples both at room and cryogenic temperatures. The double- core tape with 5% MgO addition recorded the highest failure point at 160 MPa. In addition to the strengthening effect that was observed in the nanosize MgO added Bi-2212 superconduc-tor tapes, the superconducting properties re-mained intact in the tapes.

关键词： Bi-2212 Superconductor Electrical Properties Mechanical Properties High Current Density Cryogenic Temperature

Effect of Strain Rate on Tensile Behavior of Sn-9Zn-xAg-ySb;{(x, y) = (0.2, 0.6), (0.2, 0.8), (0.6, 0.2), (0.8, 0.2)} Lead-Free Solder Alloys

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Materials Sciences and Applications 2023年第4期14卷 273-283页

作者： Shihab Uddin Md. abdul Gafur Mohammad Obaidur rahman Department of Physics Jahangirnagar University Savar Dhaka Bangladesh Pilot Plant and Process Development Centre Dhaka Bangladesh

The tensile properties of Sn-9Zn-xAg-ySb;{(x, y) = (0.2, 0.6), (0.2, 0.8), (0.6, 0.2), (0.8, 0.2)} lead-free solders were investigated. All the test samples were annealed at 150°C for 1 hour. The tests are carried out at room temperature at the strain rate of 4.17 × 10-3 s-1, 20.85 × 10-3 s-1, and 208.5 × 10-3 s-1. It is seen that the tensile strength increases and the ductility decrease with increasing the strain rate over the investigated range. From the strain rate change test results, the strain sensitivity values are found in the range of 0.0831 to 0.1455 due to the addition of different alloying elements.

关键词： Lead-Free Solder Strain Rate Strain Sensitivity Ductility Tensile Properties

Physico-chemical parameters for the assembly of moxifloxacin hydrochloride and cetyltrimethylammonium chloride mixture in aqueous and alcoholic media

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Chinese Journal of Chemical Engineering 2023年第5期57卷 280-289页

作者： Arnop Dutta Md.Tuhinur R.Joy Sk.Md.Ali Ahsan Mansour K.Gatasheh Dileep Kumar Malik abdul Rub Md.Anamul Hoque Mohammad Majibur rahman Nasrul Hoda D.M.Shafiqul Islam Department of Chemistry Jahangirnagar UniversitySavarDhaka 1342Bangladesh Department of Chemistry Jashore University of Science and TechnologyJashore 7408Bangladesh Department of Biochemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Laboratory for Chemical Computation and Modeling Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh CityViet Nam Faculty of Applied Technology Van Lang UniversityHo Chi Minh CityViet Nam Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Environmental Sciences Jahangirnagar UniversitySavarDhaka 1342Bangladesh Department of Neurology Henry Ford Health SystemDetroitMI 48292USA

The aggregation behavior of the mixture of cetyltrimethylammonium chloride(CTAC), a cationic surfactant, and moxifloxacin hydrochloride(MFH), a fourth-generation fluoroquinolone antibiotic drug, has been studied using the conductivity technique in aqueous and alcoholic(EtOH, 1-PrOH, and 2-BuOH)media. The study was performed at several temperatures between 298.15 and 323.15 K at 5 K *** assembly has been characterized by evaluating the micellar parameters, such as the critical micelle concentration(CMC) and the counter ion binding(β), of the CTAC + MFH mixture. The values of the CMC for the assembly of the CTAC + MFH mixture were reliant on the composition of alcohols in the mixed solvents and the temperature. The CMC values of the CTAC + MFH mixture increased with increasing temperature;that is, assembly was delayed by increased temperature. The micellization of the CTAC + MFH mixed system was delayed in alcoholic media. The observed-ΔG0mvalues for the association of the CTAC + MFH mixed system demonstrated a spontaneous aggregation process under all study *** on the-ΔH^(0)_(m) and +ΔS^(0)_(m) values, the association of the CTAC + MFH mixture is exothermic and the interaction forces acting between the CTAC and MFH species are hydrophobic, ion–dipole, and electrostatic interactions. The transfer properties and enthalpy–entropy compensation were also assessed and described comprehensively.

关键词： Moxifloxacin hydrochloride drug Aggregation Alcohol Hydrophobic interaction Critical micelle concentration Thermodynamic properties

Molecular characterization of sweet potato(Ipomoea batatas[L.]Lam)germplasms for desirable traits by using simple sequence repeats markers

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BIOCELL 2023年第1期47卷 227-237页

作者： KHANDAKAR ABUMDMOSTAFIZAR rahman abdul SHUKOR JURAIMI MDREZWAN MOLLA MUHAMMAD ASYRAFMD HATTA ZULKEFLY BIN SULAIMAN SHAMIMA SULTANA AHMED GABER BENUKAR BISWAS AKBAR HOSSAIN Tuber Crop Research Centre Bangladesh Agricultural Research InstituteGazipur1701Bangladesh Department of Crop Science Faculty of AgricultureUniversiti Putra MalaysiaUPMKuala Lumpur43400Malaysia Plant Genetic Resources Centre Bangladesh Agricultural Research InstituteGazipur1701Bangladesh Department of Agriculture Technology Faculty of AgricultureUniversiti Putra MalaysiaUPMKuala Lumpur43400Malaysia Regional Agricultural Research Station Bangladesh Agricultural Research InstituteCumilla3500Bangladesh Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Agronomy Bidhan Chandra Krishi ViswavidyalayaNadiaWB741252India Division of Agronomy Bangladesh Wheat and Maize Research InstituteDinajpur5200Bangladesh

Every breeding program that aims to create new and improved cultivars with desired traits mostly relies on information related to genetic ***,molecular characterization of germplasms is important to obtain target cultivars with desirable *** potato[Ipomoea batatas(L.)Lam]is widely considered the world’s most important crop,with great diversity in morphological and phenotypic *** genetic diversity of 20 sweet potato germplasms originating from Bangladesh,CIP,Philippines,Taiwan,and Malaysia were compared,which was accomplished by genetic diversity analysis by exploring 20 microsatellite DNA markers for germplasm characterization and *** information was effective in differentiating or clustering the sweet potato genotypes.A total of 64 alleles were generated using the 20 primers throughout the 20 germplasm samples,with locus IBS97 having the highest number of alleles(5),whereas locus IbU33 had the fewest alleles(2).The alleles varied in size from 105(IbU31)to 213 base pairs(IBS34).The Polymorphism Information Content(PIC)values for the loci IbL46 and IBS97 varied from 0.445 to ***97 has the highest number of effective alleles(3.704),compared to an average of *** average Shannon’s diversity index(H)was 1.003,ranging from 0.673 in IbU3 to 1.432 in *** value of gene flow(Nm)varied between 0.000 and 0.005,with an average of 0.003,whereas genetic differentiation(FST-values)ranged between 0.901 and *** sweet potato germplasm included in this study had a broad genetic ***1 ***9 and SP12 ***18 germplasm pairings had the greatest genetic distance(GD=0.965),while SP1 ***2 germplasm couples had the least genetic diversity(GD=0.093).Twenty genotypes were classified into two groups in the UPGMA dendrogram,with 16 genotypes classified as group“A”and the remaining four genotypes,SP10,SP18,SP19,and SP20,classified as group“B.”According to cluster analysis,the anticipated heterozygosity(gene diversity)of Nei

关键词： Sweet potato Simple sequence repeats(SSRs) Genetic diversity Dendrogram

Variceal hemorrhage:Saudi tertiary center experience of clinical presentations,complications and mortality

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World Journal of Hepatology 2012年第9期4卷 268-273页

作者： Hind I Fallatah Haifaa Al Nahdi Maan Al Khatabi Hisham O Akbar Yousif A Qari abdul rahman Sibiani Salim Bazaraa Department of Medical King Abdul Aziz University Hospital Jeddah Saudi ArabiaJeddah 21423Saudi Arabia

AIM:To determine the clinical presentation,underlying etiology and short-and long-term outcomes of acute variceal bleeding(AVB).METHODS:A retrospective descriptive cohort study of cirrhotic patients with AVB who were admitted to King abdul Aziz University Hospital between January 2005 and December *** obtained demographic data for all *** each patient we also obtained the clinical data at presentation;cause of liver cirrhosis,bleeding presentation(hematemesis and/or melena),presence of ascites,hepatic encephalopathy and renal impairment(RI) or hepatorenal *** carried out complete blood count,prothrombin time evaluation,and liver function *** also report all episodes of re-bleeding after the first episode of AVB,both during the initial admission and after *** recorded the length of stay for each patient and thereby calculated the mean duration of stay for all *** length of follow-up after the first AVB and the outcome for each patient at the end of the study period were *** of mortality either related to liver disease or non-liver disease cause were ***:A 125 patients were enrolled in the *** number of episodes of AVB for each patients varied between 1 and *** from the first attack of AVB to death was 20.38 mo(SD 30.86),while the length of follow-up for the living patients was 53.58 mo(SD 24.94).Total number of AVB admissions was *** hepatitis C,the commonest underlying etiology for liver disease,was present in 46(36.8%) *** 35(28%) patients had received a primary prophylactic β-blocker before the first bleeding *** mean hemoglobin level at the time of admission was 8.59 g/dL(SD 2.53).Most patients had Child-Pugh Class C 41(32.8%) or Class B 72(57.6%) *** was the predominant symptom and was found in 119(95.2%) patients,followed by melena in 75(60.0%) *** of variable extent was documented in 93(74.4%) *** identified hepati

关键词： Endoscopy Liver disease Mortality Outcome Varices Variceal bleeding

Deep Learning Framework for Precipitation Prediction Using Cloud Images

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Computers, Materials & Continua 2022年第8期72卷 4201-4213页

作者： Mirza Adnan Baig Ghulam Ali Mallah noor Ahmed Shaikh Shah abdul Latif University Khairpur77150Pakistan

Precipitation prediction(PP)have become one of the significant research areas of deep learning(DL)and machine vision(MV)techniques are frequently used to predict the weather variables(WV).Since the climate change has left significant impact upon weather variables(WV)and continuously changes are observed in temperature,humidity,cloud patterns and other *** cloud images contain sufficient information to predict the precipitation pattern but due to changes in climate,the complex cloud patterns and rapid shape changing behavior of clouds are difficult to consider for rainfall *** of rainfall would provide more meticulous assistance to the farmers to know about the weather conditions and to care their cash *** research proposes a framework to classify the dark cloud patterns(DCP)for prediction of *** framework consists upon three steps to classify the cloud images,first step tackles noise reduction operations,feature selection and preparation of *** step construct the decision model by using convolutional neural network(CNN)and third step presents the performance visualization by using confusion matrix,precision,recall and accuracy *** research contributes(1)real-world clouds datasets(2)method to prepare datasets(3)highest classification accuracy to predict estimated as 96.90%.

关键词： Machine vision SIFT features dark cloud patterns precipitation agriculture

Scheduler Algorithm for Multi-Class Switch with Priority Threshold

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International Journal of Communications, Network and System Sciences 2012年第6期5卷 313-320页

作者： abdul Aziz abdul rahman Kamaruzzaman Seman Kamarudin Saadan Ahmad Kamsani Samingan Azreen Azman Faculty of Computer Science & IT Universiti Putra Malaysia (UPM) Selangor Malaysia Faculty of Science & Technology Universiti Sains Islam Malaysia (USIM) Negeri Sembilan Malaysia Next Generation Access Telekom Research & Development Selangor Malaysia

The requirement for guaranteed Quality of Service (QoS) have become very essential since there are numerous network base application is available such as video conferencing, data streaming, data transfer and many more. This has led to the multi-class switch architecture to cater for the needs for different QoS requirements. The introduction of threshold in multi-class switch to solve the starvation problems in loss sensitive class has increased the mean delay for delay sensitive class. In this research, a new scheduling architecture is introduced to improve mean delay in delay sensitive class when the threshold is active. The proposed architecture has been simulated under uniform and non-uniform traffic to show performance of the switch in terms of mean delay. The results show that the proposed architecture has achieved better performance as compared to Weighted Fair Queueing (WFQ) and Priority Queue (PQ).

关键词： Scheduler Priority Thresholds Multi-Class Quality of Service (QOS)

Germanium Based Two-Dimensional Photonic Crystals: The Hexagonal and Honeycomb Lattices

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Optics and Photonics Journal 2019年第3期9卷 25-36页

作者： Fairuz Aniqa Salwa Muhammad Mominur rahman Muhammad Obaidur rahman Muhammad abdul Mannan Chowdhury Department of Physics Jahangirnagar University Dhaka Bangladesh

The properties of two-dimensional (2D) photonic crystals (PCs) composed of germanium (Ge) are discussed. We investigate polarization-dependent photonic band diagrams (transverse electric and transverse magnetic polarizations), gap maps, surface plots, contour maps, etc. for 2D PCs with Ge rods in air and vice versa for two different lattices geometries, namely hexagonal and honeycomb lattices. The obtained graphs for the four possible combinations are presented in this paper. All the graphs depict clear photonic band gaps. The conditions for the largest TE and TM band gaps are described. The honeycomb lattice of Ge rods in air background offers a large complete photonic band gap Δω/ωm greater than 8% (for rod radius of r = 0.2 μm). Using these data, new Ge based photonic devices can be fabricated to confine, control and manipulate light in a more useful way.

关键词： Photonic Crystals Transverse Electric Modes Transverse Magnetic Modes Photonic Band Diagram Gap Map Hexagonal Lattice Honeycomb Lattice

Descriptive assessment on diabetic retinopathy screening in an awareness programme in Malaysia

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1808-1813页

作者： Nor Fariza Ngah Nor Asiah Muhamad Zalifa Zakiah Asnir Roslin Azni abdul Aziz Zaidah Mhad Kassim Siti Aishah Sahar Nor Azita Ahmad Tarmidzi Chan Li Yen Rosmawati Uthman Narjis Satar noor Zahirah Husain Azian Adnan John Mathen Kayalakakathu Bariyah Kadas noor Suriani Mohamad Shaiful Azlan Kassirn Department of Ophthalmology Shah Alam HospitalSelangor 40000Malaysia Sector for Evidence Based Healthcare National Institutes of HealthMinistry of HealthSelangor 40170Malaysia Institute for Public Health National Institutes of HealthMinistry of HealthSelangor 40170Malaysia Department of Ophthalmology Ampang HospitalSelangor 68000Malaysia Department of Ophthalmology Serdang HospitalSelangor 43000Malaysia Department of Ophthalmology Putrajaya HospitalFederal Territory 62250Malaysia Department of Ophthalmology Kuala Lumpur HospitalFederal Territory 50586Malaysia Department of Ophthalmology Tengku Ampuan Rahimah HospitalSelangor 41200Malaysia Department of Ophthalmology Selayang HospitalSelangor 68100Malaysia Department of Ophthalmology Sungai Buloh HospitalSelangor 47000Malaysia Selangor State Health Department Ministry of HealthSelangor 40100Malaysia

AIM:To determine the prevalence of diabetic retinopathy(DR)among diabetic patients at the primary health clinics in Selangor,***:All diabetic patients were screened in Retinal Disease Awareness Programme(RDAP)and those who had significant DR changes were referred to the hospital for further *** analyses were done to determine the prevalence of DR and sociodemographic characteristics among patients with *** and multivariable analysis using Logistic regression were performed to find association and predictor factors in this ***:A total of 3305 patients aged 40y and above were screened for *** patients screened,9%patients were found to have DR and other visual complication such as maculopathy(0.9%),cataract(4.8%)and glaucoma(0.4%).The mean age of patients without retinopathy was 57.82±8.470y and the mean age of patients with DR was 63.93±*** 61.5%of the patients screened were aged below 60y and 38.5%were aged 60y and *** of the patients screened were women 58.5%and Malay in the age group of 50-59y,while 27%were aged *** association were found between age,sex,race,visual loss and ***:Although the prevalence of DR among patients is not alarming,effective interventions need to be implemented soon to avert a large burden of visual loss from DR.

关键词： diabetic retinopathy retinal disease awareness programme eye screening Selangor