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Measurement and correlation of solubility of diosmin in four pure solvents and β-cyclodextrin solution at 298.15K to 333.15K

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Chinese Journal of Chemical Engineering 2015年第5期23卷 812-815页

作者： md.khalid Anwer Faiyaz Shakeel Department of Pharmaceutics College of Pharmacy Salman Bin Abdulaziz University Center of Excellence in Biotechnology Research King Saud University Department of Pharmaceutics College of Pharmacy King Saud University

The aim of present study was to measure and correlate the solubility of poorly water-soluble flavonoid diosmin in water, ethanol, isopropyl alcohol （IPA）, polyethylene glycol-400 （PEG-400） and β-cyclodextrin （β-CD） aqueous solution （0.02 mol·L^-1 ）. The solubility of diosmio was measured using the shake flask method from （298.15 to 333.15） K at atmospheric pressure. The experimental solubilities of diosmin were regressed by the modified Apelblat model with a relative deviation in the range of 0.048% to 5.940%. The correlation coefficients were observed in the range of 0.9957 to 0.9995. The solubility of diosmin was found to be increased with temperature in all sample matrices investigated. The mole fraction solubility of diosmin was found to be higher in 5-CD aqueous solution and PEG-400 as compared to water, ethanol and IPA. Based on solubility data of present study, diosmin was considered as practically insoluble in water, insoluble in ethanol ＆ IPA and soluble in PEG- 400 and β-CD aqueous solution.

关键词： Apelblat model Cyclodextrin Diosmin Solubility Thermodynamics

Medical Image Enhancement Using Morphological Transformation

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Journal of Data Analysis and Information Processing 2016年第1期4卷 1-12页

作者： Raihan Firoz md. Shahjahan Ali M. Nasir Uddin Khan md. khalid Hossain md. Khairul Islam md. Shahinuzzaman Department of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Institute of Electronics Atomic Energy Research Establishment Savar Dhaka Bangladesh

Medical imaging includes different modalities and processes to visualize the interior of human body for diagnostic and treatment purpose. However, one of the most common degradations in medical images is their poor contrast quality and noise. The existence of several objects and the close proximity of adjacent pixels values make the diagnostic process a daunting task. The idea of image enhancement techniques is to improve the quality of an image. In this study, morphological transform operation is carried out on medical images to enhance the contrast and quality. A disk shaped mask is used in Top-Hat and Bottom-Hat transform and this mask plays a vital role in the operation. Different types and sizes of medical images need different masks so that they can be successfully enhanced. The method shown in this study takes a mask of an arbitrary size and keeps changing its size until an optimum enhanced image is obtained from the transformation operation. The enhancement is achieved via an iterative exfoliation process. The results indicate that this method improves the contrast of medical images and can help with better diagnosis.

关键词： Medical Image Image Enhancement Morphological Transform Top-Hat Transform Bottom-Hat Transform MATLAB

Assessment of Water Quality and Microbial Load of Dhaleshwari River Tangail, Bangladesh

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Advances in Microbiology 2017年第6期7卷 523-533页

作者： md. khalid Hassan Real Natasha Khanam md. Younus Mia Marufa Nasreen Department of Environmental Science and Resource Management Mawlana Bhashani Science and Technology University Tangail Bangladesh Department of Biotechnology and Genetic Engineering Mawlana Bhashani Science and Technology University Tangail Bangladesh

The present study was undertaken to investigate some water quality parameters (pH, BOD, DO and water temperature), anion concentration (PO43- , SO42- and NO3- ) and the availability of some selected microorganisms consisted of total coliform, fecal coliform (Escherichia coli) and Vibrio cholerae in the Dhaleshwari river during the period from April to June 2015. The water samples were collected from three different stations of the river namely Belta (St-1), Kendua (St-2) and Charabari (St-3) under the Porabari union at Tangail Sadar Upazilla. Water temperature varied from 29.5 oC in June to 31.7 oC in May with a highest mean 31.17 ± 0.47 in May. The pH of water was slightly alkaline in nature and ranged between 7.25 in June and 8.45 in April. Mean concentrations of BOD 0.87 ± 0.19, 1.12 ± 0.6 and 0.97 ± 0.67 were recorded in April, May and June respectively. Highest PO42- value 4.4 mg/l was found in May and lowest value of PO42- 1.74 mg/l was found in June. Mean sulfate values at different months of Dhaleshwaririver were 6.61 ± 1.78 mg/l, 7.61 ± 2.16 mg/l and 3.68 ± 0.23 mg/l respectively. Nitrate concentration in water samples varied from 0.51 mg/l in June to 3.66 mg/l in April. Total coliforms bacteria were found high in all water samples and values ranged from 11.05 × 108 - 19 × 1023 cfu/ml. The highest load of total coliforms bacteria was recorded at St-2 in May and the lowest was at St-1 in April. The highest concentration of (Escherichia coli counted in water sample was 6 × 1013 cfu/ml at St-2 during June, while lowest concentration was 5 × 105 cfu/ml at St-1 during May. The highest concentration of Vibrio cholerae was 9.66 × 1014 cfu/ml at St-1 during June, while lowest concentration was 4.2 × 108 cfu/ml at St-3 during April. The high number of total coliform, Escherichia coli and Vibrio cholerae indicated significant level of microbial pollution in Dhaleshwari river. The presence of pathogenic organisms may pose not only health hazards to the users of the ri

关键词： Bacteria Total Coliform Escherichia coli Vibrio cholerae

Simulation and Modelling of Water Injection for Reservoir Pressure Maintenance

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Computers, Materials & Continua 2022年第9期72卷 5761-5776页

作者： Rishi Dewan Adarsh Kumar Mohammad khalid Imam Rahmani Surbhi Bhatia md.Ezaz Ahmed Department of Physics University of Petroleum&Energy StudiesDehradun 248007UttarakhandIndia Department of Computer Science University of Petroleum&Energy StudiesDehradun 248007UttarakhandIndia College of Computing and Informatics Saudi Electronic UniversityRiyadh 11673Saudi Arabia Department of Information Systems College of Computer Science and Information TechnologyKing Faisal UniversityAl Hasa 36362Saudi Arabia

Water injection has shown to be one of the most successful,efficient,and cost-effective reservoir management *** re-injecting treated and filtered water into reservoirs,this approach can help maintain reservoir pressure,increase hydrocarbon output,and reduce the environmental *** goal of this project is to create a water injection model utilizing Eclipse reservoir simulation software to better understand water injection methods for reservoir pressure maintenance.A basic reservoir model is utilized in this *** simulation designs,the reservoir length,breadth,and thickness may be changed to different *** water-oil contact was discovered at 7000 feet,and the reservoir pressure was recorded at 3000 pounds per square inch at a depth of 6900 *** aquifer chosen was of the Fetkovich type and was linked to the reservoir in the j+*** porosity was estimated to be varied,ranging from 9%to 16%.The residual oil saturation was set to 25%and the irreducible water saturation was set at 20%.The vertical permeability was set at 50 md.as a *** Volume Temperature(PVT)data was used to estimate the gas and water characteristics.

关键词： Eclipse water injection reservoir modeling simulation oil saturation

Development of Nanostructure Formation of Fe73.5Cu1Nb3Si13.5B9Alloy from Amorphous State on Heat Treatment

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World Journal of Nano Science and Engineering 2015年第4期5卷 107-114页

作者： md. khalid Hossain Jannatul Ferdous md. Manjurul Haque A. K. M. Abdul Hakim Institute of Electronics Atomic Energy Research Establishment Savar Dhaka Bangladesh Department of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Department of Glass and Ceramic Engineering Bangladesh University of Engineering and Technology Dhaka Bangladesh

Iron-based amorphous alloys have attracted technological and scientific interests due to their excellent soft magnetic properties. The typical nanocrystalline alloy with the composition of Fe73.5Cu1Nb3Si13.5B9 known as FINEMENT has been studied for structural properties analysis. Recently, it is found that after proper annealing the amorphous alloy like Fe73.5Cu1Nb3Si13.5B9 has a transition to the nanocrystalline state, thus exhibiting good magnetic properties. The alloy in the form of ribbon of 10 mm width and 25mm thickness with the composition of Fe73.5Cu1Nb3Si13.5B9 was prepared by rapid quenching method. The prepared ribbon sample has been annealed for 30 min in a controlled way in the temperature range 490℃ - 680℃. By analyzing X-ray diffraction (XRD) patterns, various structural parameters such as lattice parameters, grain size and silicon content of the nanocrystalline Fe(Si) grains, crystallization behavior and nanocrystalline phase formation have been investigated. In the nanocrystalline state, Cu helps the nucleation of α-Fe(Si) grains while Nb controls their growth, Si and B has been used as glass forming materials. Thus on the residual amorphous, the nanometric Fe(Si) grains develops. From broadening of fundamental peaks, the optimum grain size has been determined in the range of 7 - 23 nm.

关键词： Fe Based Alloy Rapid Solidification Crystallization Behavior Nanocrystalline Phase Formation

Study and Characterization of Soft Magnetic Properties of Fe73.5Cu1Nb3Si13.5B9Magnetic Ribbon Prepared by Rapid Quenching Method

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Materials Sciences and Applications 2015年第12期6卷 1089-1099页

Nanocrystalline Fe-based alloys offer a new opportunity for tailoring soft magnetic materials. Nanocrystalline alloy in the form of ribbon with the composition of Fe73.5Cu1Nb3Si13.5B9 was prepared by rapid quenching method for soft magnetic properties analysis. The rapidly quenched alloy has been annealed in a controlled way in the temperature range 490℃ to 680℃ and annealing time 1 min to 60 min. The study of the structural parameters has been investigated by means of XRD analysis. Magnetic properties were analyzed by measuring B-H loop and frequency dependence of initial permeability. Enhanced value of initial permeability by two orders of magnitude and very low value of relative loss factor of the order of 10–3 has been observed with the variation of annealing temperature and time. The initial permeability for the optimum annealed sample has been found 23,064 as compared with 360 for its amorphous counterpart. The initial permeability spectra show dispersion around 100 kHz. Magnetic hysteresis has been investigated by measuring B-H loops at various magnetic fields for different annealing temperature and time. The coercivity and remanence has been found to decrease significantly for optimized annealed condition compared to as-cast state. The core loss of the samples decreases with the annealing time which indicates the good magnetic property of soft magnetic materials.

关键词： Nanocrystalline Alloy Magnetic Property Hysteresis Loop Permeability Coercivity Remanence

Performance Evaluation of a DS-CDMA System in a Rayleigh Fading Environment

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World Journal of Engineering and Technology 2016年第1期4卷 1-9页

作者： M. A. Rahman M. M. Alam md. khalid Hossain md. Khairul Islam Khan M. Nasir Uddin md. Shahinuzzaman Department of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Institute of Electronics Atomic Energy Research Establishment Savar Bangladesh

This work represents the performance evaluation of DS-CDMA in a Rayleigh fading environment. Performance analysis was carried out for a DS-CDMA system to evaluate the signal-to-noise ratio (SNR), signal-to-interference ratio (SIR) and bit error rate (BER) for different modulation schemes like ASK, PSK and FSK. Results were evaluated at different data rates and were presented in terms of SNR, SIR and BER. Computer simulation was also carried out by using Matlab to evaluate the signal waveforms with and without addition white Gaussian noise (AWGN). Butterworth filtered waveform was given to get better signal quality. Decoded output waveforms were also evaluated to confirm the simulation.

关键词： DS-CDMA Rayleigh Fading Performance Analysis SNR BER ASK PSK FSK MATLAB AWGN

Assessment of ecological risk for heavy metals in surface sediment of an urban river in a developing country

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International Journal of Sediment Research 2023年第6期38卷 834-846页

作者： md.Saiful Islam md.Humayun Kabir Mir Mohammad Ali md.Towhidul Islam Asfia Niger md.Humayun Kabir Zulhilmi Ismail Sujat Ahmed khalid A.Ibrahim Abubakr M.Idris Department of Soil Science Patuakhali Science and Technology University Department of Environmental Science and Resource Management Mawlana Bhashani Science and Technology University Department of Aquaculture Sher-e-Bangla Agricultural University Department of Soil Science Bangabandhu Sheikh Mujibur Rahman Agricultural University Centre for River and Coastal Engineering(CRCE) Universiti Teknologi Malaysia(UTM) Department of Water & Environmental Engineering Faculty of Civil EngineeringUniversiti Teknologi Malaysia(UTM) Environment Center for People & Environ(CPE) Department of Biology College of ScienceKing Khalid University Center for Environment and Tourism Studies and Research King Khalid University Department of Chemistry College of ScienceKing Khalid University Research Center for Advanced Materials Science(RCAMS) King Khalid University

The speed of increasing threats to the riverine water resources makes it more critical to protect the health of Old Brahmaputra River *** current study was done to investigate the concentrations,distributions,sources,and ecological risk of heavy metals in surface sediment from the Old Brahmaputra River,*** were collected from seven sites and analyzed with an inductively coupled plasma-mass spectrometer(ICP-MS).The results showed that mean concentrations(mg/kg) of heavy metals were in the order of nickel(Ni)(44.69)> chromium(Cr)(30.16)> lead(Pb)(19.31)>copper(Cu)(17.84)> cadmium(Cd)(3.94)> arsenic(As)(2.73).The contamination factor(CF),pollution load index(PLI),enrichment factor(EF),and geo-accumulation index(Igeo) indicated low to moderate *** unit analysis revealed that the studied metals from all stations posed low *** sediment of the study river was uncontaminated to moderately contaminated,posing a minimal ecological ***,Cr,Ni,and Pb originated from anthropogenic sources rather than geogenic sources,and caused the severity of *** this regard,pollutant-based intensive monitoring of heavy metals and holistic ecological risk assessments are required to maintain a sound and healthy aquatic environment in the river.

关键词： Heavy metals Sediment quality Ecological risk Old Brahmaputra river Source identification

Automatic Real-Time Medical Mask Detection Using Deep Learning to Fight COVID-19

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Computer Systems Science & Engineering 2022年第9期42卷 1181-1198页

作者： Mohammad khalid Imam Rahmani Fahmina Taranum Reshma Nikhat md.Rashid Farooqi Mohammed Arshad Khan College of Computing and Informatics Saudi Electronic UniversityRiyadhSaudi Arabia Computer Science and Engineering Department Muffakham Jah College of Engineering and TechnologyOsmania UniversityHyderabadTelanganaIndia Department of Commerce and Business Management Maulana Azad National Urdu UniversityHyderabadTelanganaIndia Department of Accountancy College of Administrative and Financial SciencesSaudi Electronic UniversityRiyadSaudi Arabia

The COVID-19 pandemic is a virus that has disastrous effects onhuman lives globally;still spreading like wildfire causing huge losses to humanityand economies. There is a need to follow few constraints like social distancingnorms, personal hygiene, and masking up to effectively control the virus *** proposal is to detect the face frame and confirm the faces are properly covered with masks. By applying the concepts of Deep learning, the results obtainedfor mask detection are found to be effective. The system is trained using4500 images to accurately judge and justify its accuracy. The aim is to developan algorithm to automatically detect a mask, but the approach does not facilitatethe percentage of improper usage. Accuracy levels are as low as 50% if the maskis improperly covered and an alert is raised for improper placement. It can be usedat traffic places and social gatherings for the prevention of virus transmission. Itworks by first locating the region of interest by creating a frame boundary, thenfacial points are picked up to detect and concentrate on specific features. Thetraining on the input images is performed using different epochs until the artificialface mask detection dataset is created. The system is implemented using TensorFlow with OpenCV and Python using a Jupyter Notebook simulation environment. The training dataset used is collected from a set of diverse open-sourcedatasets with filtered images available at Kaggle Medical Mask Dataset by Mikolaj Witkowski, Kera, and Prajna Bhandary. To simulate MobilNetV2 classifier isused to load and pre-process the image dataset for building a fully connectedhead. The objective is to assess the accuracy of the identification, measuringthe efficiency and effectiveness of algorithms for precision, recall, and F1 score.

关键词： COVID-19 pandemic convolution neural network deep learning face detection facemask detection global health machine learning