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Rheology and lubricity characteristics study at different temperatures using synthesized SnO_(2) nanoparticles in KCl free bentonite water base mud

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Petroleum Research 2023年第4期8卷 541-549页

作者： A.B.M.Ariful Bari Khandaker Nayem Ahmed Md Saiful alam Department of Petroleum and Mining engineering Shahjalal University of Science and TechnologySylhet3114Bangladesh Department of Petroleum and Mining engineering Jashore University of Science and TechnologyJashore7408Bangladesh

Drilling mud is a major concerning element due to its high operational and economic impact on the drilling *** additives are introduced to enhance the efficiency of drilling fluid,but none of them could perfectly achieve their proposed efficacy in drilling *** conceived several nanoparticles(NPs)in drilling fluid to dissolve this *** a singular instance,commercial tin oxide(SnO_(2))nanoparticles were utilized to analyze the influence of NPs on the rheological and filtration properties of inorganic KCl salt-based drilling ***,the effect of SnO_(2) NPs on mud lubricity characteristics is not studied ***,due to the hazardous behavior of KCl,its use is very ***,we consider a KCl-free bentonite water-based mud to avoid any environmental damages from drilling *** also use SnO_(2) NPs that is synthesized in our laboratory by co-precipitation *** addition to rheological and filtration properties,we also investigate the effect of NPs on mud's lubricity that was not considered in the previous *** fluid properties are measured at five different NPs concentrations of 0.10,0.25,0.50,0.75&1.0 wt%,and at six different temperatures of 30,40,50,60,70,and 80°C,while filtration properties are measured using API low-pressure low temperature(LPLT)*** addition of 0.1 wt%SnO_(2) NPs increases plastic viscosity,yield point,10 s gel strength,and 10 min gel strength by 10%,63%,20%,and 14%,*** maximum reduction in lubricity coefficient is found to be 14%at NPs concentration of 1.0 wt%.The NPs concentration of 0.5 wt%yielded a reduction in fluid loss and mud cake thickness by 8.1%and 34%,*** study suggests that SnO_(2) NPs can be employed as an additive to improve the rheology,lubricity,and filtration properties of KCl-free bentonite water-based drilling mud.

关键词： Mud Rheology Lubricity Tin oxide Nanoparticles KCl

Hygiene,sanitation facility,and assessment of drinking water quality in the schools of Chattogram city,Bangladesh

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Global Health Journal 2022年第4期6卷 204-211页

作者： Md.Zobaidul alam Abdullah Al Mukarrom Department of Microbiology University of ChittagongChattogram 4331Bangladesh

Objective:This study is designed to evaluate the microbiological safety concern of drinking water of the 50 schools of Chattogram city,Bangladesh,and to investigate the sanitation and hygiene conditions of the schools,which are directly related to the health of thousands of ***:In this study,pour plate method used for total viable count(TVC),most probable number(MPN)method used for the total coliform count(TCC)and fecal coliform count(FCC),and four selective media used to isolate pathogenic bacteria from drinking water samples,and then identified by using morphological,cultural,and biochemical *** investigate the water,sanitation,and hygiene conditions a structured questionnaire was ***:A total of 46% samples were found above the acceptable limit(>500 CFU/ml)for TVC count,52%sam-ples had coliform,and 28% samples had fecal coliform,which exceeded the WHO guideline *** categorized 50 studied schools into five groups and found the highest TVC(67%)and TCC(83%)in the water samples of city corporation ***,Salmonella,Shigella,enterobacter,Citrobacter,Klebsiella,and Yersinia were isolated and identified from drinking water *** most schools,drinking water reservoirs were found impure and contaminated by various *** government primary schools,a toilet is used by 143 students,whereas in pri-vate english medium schools,a toilet is used by 30 students and found ***-washing soap was supplied in only 14% of government primary schools,but 100% in private english medium ***:Our findings suggest that drinking water in most of the schools was found contaminated by *** hygiene,sanitation,and contaminated drinking water seem responsible for different kinds of ***-over,this study indicates the necessity for raising awareness about drinking water,hygiene,and sanitation facil-ities of schools,which should monitor at regular intervals.

关键词： Pour plate method Hygiene and sanitation Most probable number Schools Chattogram city

Annual pattern of zooplankton communities and their environmental response in a subtropical maritime channel system in the northern Bay of Bengal, Bangladesh

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Acta Oceanologica Sinica 2018年第8期37卷 65-73页

作者： ABDULLAH Al Mamun alam Md.Didarul AKHTAR Aysha XU Henglong ISLAM Md.Shafiqul MUSTAFA kamal Abu Hena UDDIN M Muslem alam Md.Wahidul Laboratory of Microbial ecology Ocean University of China Faculty of Marine Sciences and Fisheries University of Chittagong Department of Animal Science and Fishery Faculty of Agriculture and Food Sciences Universiti Putra Malaysia Campus Bintulu

Zooplankton plays an important role in aquatic food webs by fluxing of energy from primary producer to subsequent trophic levels in the food chain. The annual pattern of zooplankton communities and potential environmental drivers were studied in the Kohelia channel, Bangladesh from summer 2014 to spring *** were collected using net at a depth of 1 m. A total of 32 species belonged to 18 orders, 27 families and 15 taxonomic groups were identified. Of these species, 22 distributed in all four seasons of which 8 were dominant and highly contributing to the total communities. Species number peaked in summer next to winter and fall in spring while maximum abundance was in summer and minimum in spring. Multivariate analyses showed that there was a clear annual pattern in the zooplankton communities. Species diversity and evenness peaked in spring but fall in autumn while the high value of species richness was found in winter. Biological-environmental best matching（BIO-eNV） analyses conformed that community pattern of zooplankton was mainly driven by transparency salinity, and temperature individually or combined with water nutrients. These results demonstrate that annual pattern of the zooplankton community shaped by channel environmental factors in subtropical channel ecosystems, thus might be used for community-based subtropical coastal water bioassessment.

关键词： zooplankton trophic levels subtropical channel community structure multivariate approach

Adaptive Runtime Monitoring of Service Level Agreement Violations in Cloud Computing

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Computers, Materials & Continua 2022年第6期71卷 4199-4220页

作者： Sami Ullah Khan Babar Nazir Muhammad Hanif Akhtar Ali Sardar alam Usman Habib Department of Computer Science COMSATS UniversityAbbottabad CampusPakistan Faculty of Computer Science and engineering Ghulam Ishaq Khan(GIK)Institute of Engineering Sciences and Technology TopiPakistan IFahja Pvt Limited PeshawarPakistan Department of Computer Science National University of Computer and Emerging Sciences IslamabadChiniot-Faisalabad CampusPakistan

The cloud service level agreement(SLA)manage the relationship between service providers and consumers in cloud *** is an integral and critical part of modern era IT vendors and communication *** to low cost and flexibility more and more consumers delegate their tasks to cloud providers,the SLA emerges as a key aspect between the consumers and *** monitoring of Quality of Service(QoS)attributes is required to implement SLAs because of the complex nature of cloud *** other factors,such as user reliability,satisfaction,and penalty on violations are also taken into ***,there is no such policy of cloud SLA monitoring to minimize SLA *** this work,we have proposed a cloud SLA monitoring policy by dividing a monitoring session into two parts,for critical and non-critical *** critical and non-critical parameters will be decided on the interest of the consumer during SLA *** will help to shape a new comprehensive SLA based Proactive Resource Allocation Approach(RPAA)which will monitor SLA at runtime,analyze the SLA parameters and try to find the possibility of SLA *** also have implemented an adaptive system for allocating cloud IT resources based on SLA violations and *** have defined two main components of SLA-PRAA i.e.,(a)Handler and(b)Accounting and Billing *** have also described the function of both components through *** experimental results validate the performance of our proposed method in comparison with state-of-the-art cloud SLA policies.

关键词： energy consumption penalty calculation proactive resource allocation service level agreement(SLA)monitoring SLA violation detection

Groundwater arsenic poisoning in a primary educational institution:health risks to school-going children

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Acta Geochimica 2022年第6期41卷 1069-1082页

作者： Md.Sohel Rana Md.Jahangir alam MdAbu Musa Sazal Kumar Md.Aminur Rahman Zonal Laboratory Department of Public Health Engineering(DPHE)RangpurBangladesh Department of Chemistry Carmichael CollegeRangpurBangladesh Department of Applied Chemistry and Chemical engineering Islamic UniversityKushtia7003Bangladesh School of environmental and Life Sciences The University of NewcastleCallaghanNSW2308Australia Global Centre for environmental Remediation(GCeR) College of EngineeringScience and EnvironmentThe University of NewcastleCallaghanNSW2308Australia Zonal Laboratory Department of Public Health Engineering(DPHE)Jashore-7400Bangladesh

This study aimed to estimate arsenic(As)and iron(Fe)content in tubewell water(n=58)in primary educational institutions and subsequently assess the health risks to school-going *** described that the As concentration ranged between 0.002 and 0.994 mg L^(-1)with an average value of 0.044 mg L^(-1);which exceeded the World Health Organization(WHO)provisional guideline value of 0.01 mg L^(-1).Similarly,the Fe content varied from 0.05 to 10 mg L^(-1)averaging to 2.84 mg L^(-1).Samples of 55.17%contained a greater As concentration than0.01 mg L^(-1)and 18.97%greater than Bangladesh drinking water quality(BDWQ)standard of 0.05 mg L^(-1),***,75.86%of samples contained a higher Fe concentration than the maximum Bangladesh permissible limit of 1 mg L^(-1).Health risk assessment indicated that girls are more vulnerable than boys *** average hazard quotients(HQs)for As intake through drinking water were 6.01±17.85 and 7.41±22.03 for boys and girls,respectively,implying non-carcinogenic health risks to both *** HQs for Fe intake were less than threshold value of 1 indicating no health issues may arise from Fe intake ***,consumption of As and Fe may trigger health risks to students as indicated by the hazard index(HI),which was higher than *** average cancer risk(CR)values for both boys(0.0027±0.008)and girls(0.0033±0.0099)exceeded the threshold limit of 10-6-10-4,suggesting a possibility of lifetime cancer risks to the school-going ***,school authorities should find alternative ways to ensure safe drinking water for school-going children to avoid possible cancer and non-cancer health risks through consumption of As-poisoning water.

关键词： Arsenic Iron Human health risks Groundwater

Low Profile UHF Antenna Design for Low earth-Observation CubeSats

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Computers, Materials & Continua 2022年第5期71卷 2533-2542页

作者： Md.Amanath Ullah Touhidul alam Ali F.Almutairi Mohammad Tariqul Islam School of electrical and Data engineering Faculty of Engineering and Information TechnologyUniversity of Technology SydneyUltimo NSW2007Australia Space Science Centre(ANGKASA) Institute of Climate Change(IPI)Universiti Kebangsaan MalaysiaBangi43600SelangorMalaysia Department of CSe International Islamic University Chittagong(IIUC)Chattogram4318Bangladesh electrical engineering Department Kuwait University13060KuwaitCityKuwait Department of electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangi43600SelangorMalaysia

This paper reveals a new design of UHF CubeSat antenna based on a modified Planar Inverted F Antenna(PIFA)for CubeSat *** design utilizes a CubeSat face as the ground *** is a gap of 5 mm beneath the radiating element that facilitates the design providing with space for solar *** prototype is fabricated using Aluminum metal sheet and *** antenna achieved resonance at 419 *** of the antenna has been investigated after placing a solar *** properties of solar panels made the resonance shift about 20 *** design addresses the frequency shifting issue after placing the antenna with the CubeSat *** phenomenon has been analyzed considering a typical 1U and 2U CubeSat body with the *** antenna achieved a positive realized gain of 0.7 dB and approximately 78%of efficiency at the resonant frequency with providing 85%of open space for solar irradiance onto the solar panel.

关键词： CubeSat antenna UHF antenna small satellite satellite communication

An investigation of the effects of synthesized zinc oxide nanoparticles on the properties of water-based drilling fluid

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Petroleum Research 2022年第1期7卷 131-137页

作者： Muhammad Hasibul Ahasan MdFazla Alahi Alvi Nayem Ahmed Md.Saiful alam Department of Petroleum and Mining engineering Shahjalal University of Science and TechnologySylhet3114Bangladesh

The deterioration of drilling fluid properties during deep drilling causes problems like inefficient cutting removal,fluid invasion,and shale swelling,which increases non-productive time(NPT)and *** nanoparticles(NPs)based drilling fluid are introduced to address these impediments since these particles prove their advantages in different stages of petroleum exploration and *** developments are concerned with the use of commercial zinc oxide(ZnO)NPs in inorganic KCl salt-based drilling fluid,although application of KCl in drilling fluid arouses environmental *** this study,ZnO NPs prepared in the laboratory are used in water-based drilling fluid(WBDF)to assess the effect of nanoparticles on the properties of drilling fluid at two temperature conditions of 40C and 80C.A base mud is formulated,and ZnO NPs with five different concentrations of 0.05,0.1,0.5,1.0,and 2.0 wt%are mixed with the base *** experimental analysis shows that NPs improve the rheological properties of *** the concentration of NPs was 0.1 wt%,the yield point increased by 61.54%at 40C,and when the concentration of NPs was 0.05 wt%,the yield point increased by 60%at 80***,when the concentration of NPs is 0.05 wt%,10-sec gel strengths are enhanced by 25%and 50%at 40C and 80C,*** API low-pressure low-temperature(LPLT)filter volume is not significantly affected by the addition of NPs in ***,mud cake thickness continuously reduces with the increase of NPs *** result reveals that a superior rheological improvement is achieved at low NPs concentration(0.05 wt%)at higher temperature.

关键词： Drilling fluids Zinc oxide Nanoparticles Rheology Mud cake thickness

Comparison of Sternal Wound Complication after Off-Pump CABG between Skeletonized and Pedicled LIMA Harvesting: A Single Centre experience in Bangladesh

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World Journal of Cardiovascular Surgery 2023年第6期13卷 101-110页

作者： M. Asmaul alam Al nur Md. Aslam Hossain Md. Abir Tazim Chowdhury Farhat Tabassum Nishat Munama Magdum Department of Cardiac Surgery National Institute of Cardiovascular Diseases Dhaka Bangladesh Department of Cardiac Surgery Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh Department of Cardiothoracic and Vascular Surgery Evercare Hospital Dhaka Bangladesh Department of Casualty Dhaka Medical College Hospital Dhaka Bangladesh Department of Community Medicine Shaheed Monsur Ali Medical College Dhaka Bangladesh

Background: Off-pump coronary artery bypass grafting (OPCAB) is a surgical procedure that has gained popularity due to its potential benefits over traditional coronary artery bypass grafting, including reduced morbidity and mortality. However, sternal wound complication (SWC) remains challenging following the procedure. The technique of left internal mammary artery (LIMA) harvesting has been shown to impact the incidence of SWC. This study aimed to compare the incidence of SWC between two techniques of LIMA harvesting, i.e., skeletonized and pedicled. Methods: The study was conducted at the Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University, and included 60 patients who underwent OPCAB. The patients were divided into two groups of 30 each based on the technique of LIMA harvesting used, i.e., skeletonized (group A) or pedicled (group B). The postoperative ICU care was given to each patient as per the protocol. The statistical analysis was conducted using the SPSS version 26.0 for Windows software. Results: The results showed that 5 (8.33%) patients developed SWC, with 1 (1.67%) patient in group A and 4 (6.66%) patients in group B. However, the occurrence of SWC was not statistically significant between the two groups (p = 0.35). The mean age, gender distribution, and comorbidities such as hypertension, diabetes, dyslipidemia, and anemia were also not statistically significant between the two groups. The number of smokers was statistically significant between the two groups (p = 0.03), and the occurrence of SWC was found to be higher in smoker patients in group B (p = 0.04). Preoperative and postoperative parameters such as duration of operation, duration of mechanical ventilation, duration of chest drains, duration of the central venous line, and amount of postoperative mediastinal bleeding were also not statistically significant between the two groups. The distribution of wound complications, duration of ICU stays, and hospital stay between t

关键词： Sternal Wound Complication (SWC) Off-Pump Coronary Artery Bypass Grafting (OPCAB) Left Internal Mammary Artery (LIMA) Skeletonized LIMA Harvesting Pedicle LIMA Harvesting

An overview on biochar production, its implications, and mechanisms of biochar-induced amelioration of soil and plant characteristics

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Pedosphere 2022年第1期32卷 107-130页

作者： Fasih Ullah HAIDeR Jeffrey ACOULTeR Liqun CAI Saddam HUSSAIN Sardar alam CHeeMA Jun WU Renzhi ZHANG College of Resources and environmental Sciences Gansu Agricultural UniversityLanzhou 730070China Gansu Provincial Key Lab of Arid-land Crop Science Gansu Agricultural UniversityLanzhou 730070China Department of Agronomy and Plant Genetics University of MinnesotaSt.PaulMN 55108USA Department of Agronomy University of Agriculture FaisalabadFaisalabad 38040Pakistan

The degradation of soil fertility and quality due to rapid industrialization and human activities has stimulated interest in the rehabilitation of low-fertility soils to sustainably improve crop yield. In this regard, biochar has emerged as an effective multi-beneficial additive that can be used as a medium for the amelioration of soil properties and plant growth. The current review highlights the methods and conditions for biochar production and the effects of pyrolysis temperature, feedstock type, and retention time on the physicochemical properties of biochar. We also discuss the impact of biochar as a soil amendment with respect to enhancing soil physical (e.g., surface area, porosity, ion exchange, and water-holding capacity) and chemical (e.g., pH, nutrient exchange,functional groups, and carbon sequestration) properties, improving the soil microbiome for increased plant nutrient uptake and growth, reducing greenhouse gas emissions, minimizing infectious diseases in plants, and facilitating the remediation of heavy metal-contaminated soils. The possible mechanisms for biochar-induced amelioration of soil and plant characteristics are also described, and we consider the challenges associated with biochar utilization. The findings discussed in this review support the feasibility of expending the application of biochar to improve degraded soils in industrial and saline-alkali regions, thereby increasing the usable amount of cultivated soil. Future research should include long-term field experiments and studies on biochar production and environmental risk management to optimize biochar performance for specific soil remediation purposes.

关键词： carbon sequestration crop yield pyrolysis soil amendment soil fertility soil remediation