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Journal of Energy Chemistry 2018年第1期27卷 250-263页

作者： md.Arafat rahman Yat Choy Wong Guangsheng Song De Ming Zhu Cuie Wen Faculty of Science Engineering and TechnologySwinburne University of Technology Department of Mechanical Engineering Chittagong University of Engineering and Technology School of Material Science&Engineering Anhui University of Technology School of Engineering RMIT University

The effect of annealing of Ti foils before anodization on the morphology and electrochemical performance of resultant nanoporous anatase TiO2 （np-TiO2） as anode in rechargeable lithium-ion batteries （LIBs） was investigated. The np-TiO2 anode fabricated from annealed Ti foils exhibited higher specific surface area and reduced pore diameter compared to np-TiO2 electrode fabricated from as-received Ti foils. The highly porous np-TiO2 anode fabricated from annealed Ti foils exhibited 1st discharge capacity of 453.25 mAh/g and reduced to 172.70 mAh/g at 1 C current rate after 300 cycles; whilst the np-TiO2 electrode fabricated from the as-received Ti foils exhibited 1st discharge capacity of 213.30 mAh/g and reduced to 160.0 mAh/g at 1 C current rate after 300cycles. Even after 400cycles, such np-TiO2 electrode exhibited a reversible capacity of 125.0 mAh/g at 2.5 C current rate. Compared to the untreated Ti foils, the enhanced electro- chemical performance of np-TiO2 anode fabricated from annealed Ti foils was ascribed to the annealing- induced removal of residual stress among the Ti atoms. The benefit of annealing process can reduce pore size of as-fabricated np-TiO2.

关键词： Annealing Nanoporous Anatase Titanium oxide Anode Lithium-ion battery

Soil resistivity and ground resistance for dry and wet soil

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Journal of Modern Power Systems and Clean Energy 2017年第2期5卷 290-297页

作者： md.Abdus SALAM Quazi Mehbubar rahman Swee Peng ANG Fushuan WEN Department of Electrical and Electronic Engineering Faculty of EngineeringUniversiti Teknologi BruneiJalan Tungku LinkBandar Seri BegawanBrunei-Muara BE1410Brunei Darussalam Department of Electrical and Computer Engineering The University of Western OntarioLondonOntario N6A 5B9Canada

In this paper, soil resistivity and ground resistance at two different sites near an electrical substation are measured using a grounding system grid with and without rods. With the Wenner four-pole equal-method, the soil resistivity is measured at both selected sites, one of which contains wet soil while the other contains dry soil. Cymgrd simulation software is then used to determine the acceptability of these measured resistivity values by finding out the root mean square error between the measured and calculated values for both wet and dry soil sites. These values for wet and dry soil sties were found to be only 0 %and 4.92 %, respectively, and deemed acceptable. The measured soil resistivity values were then used to evaluate the ground resistance values of a grounding grid ‘with rod’for the wet soil site and ‘without rods’ for the dry soil site,and then compared with the simulated ground resistance values. These comparisons were also found to be in good agreement. In addition, ground potential rise, maximum permissible step and touch potentials have also been estimated using the simulation software.

关键词： Grid with rods Grid without rods Fall-ofpotential method Soil resistivity Ground resistance

Contribution of non-timber forest products to the livelihoods of the forest-dependent communities around the Khadimnagar National Park in northeastern Bangladesh

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Regional Sustainability 2021年第3期2卷 280-295页

作者： md.Habibur rahman Bishwajit ROY md.Shahidul ISLAM Laboratory of Tropical Forest Resources and Environments Division of Forest and Biomaterials ScienceGraduate School of AgricultureKyoto UniversityKyoto606-8502Japan Bangladesh Institute of Social Research Trust LalmatiaDhaka1207Bangladesh Climate Change andSustainable Development Policies Faculty of ScienceUniversity of LisbonLisbon1749-016Portugal Research and Development Cell Bangladesh Knitwear Manufacturers and Exporters AssociationDhaka1000Bangladesh

Non-timber forest products(NTFPs)play a significant role in the improvement of the forest-dependent people’s livelihoodsaround the world,strengthening protection for the sustainable use of *** purpose of this research was to evaluate the influence of occupational category-wise(fuelwood collectors,farmers,small-scale businessmen,day labourers,and tea estate labourers)dependencyon NTFPsand the role of NTFPs on household income around the Khadimnagar National Park(KNP)in northeastern *** 2014,178purposively selected respondents from four villages(out of 22 villagesaround the KNP)were interviewed face-to-face using a semi-structured *** study observed that these forest-dependent communities utilized resources of the KNP mainly for domestic energy supply,household income,and house *** showed that income from NTFPs made a significant contribution to family *** data analysis indicated that small-scale businessmen earned relatively more income from NTFPs,followed by tea estate labourersand day *** study revealed significant negative relationships of the distance of households from the forest with the amount of NTFPs collected(P<0.01)and monthly income from NTFPs(P<0.01).Positive significant relationships were found between the amount of NTFPs collected and the time spent in NTFP collection(P<0.001),as well as betweenmonthly income from NTFPs and family size(P<0.001).The fuelwood collectors and farmers collected significantly greater amounts of NTFPs per trip(P<0.001)than other occupational *** households that were moderately to highly dependent on NTFPs collected significantly higher amounts of NTFPs pertrip(P<0.01)than the households that were moderately dependent and less dependent on *** dependence on KNP’sresources,community’sappreciation of the KNP’s ecosystem services for villagers’livelihoods,and community’s high levels of concern for forest conservation provided a foundation

关键词： Forest dependency Household income Non-timber forest products Forest sustainability Occupational categories Khadimnagar National Park

Assessment of heavy metal contamination in the sur?cial sediments from the lower Meghna River estuary, Noakhali coast, Bangladesh

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International Journal of Sediment Research 2021年第3期36卷 384-391页

作者： Mohammad Abdul Momin Siddique Mahfuzur rahman Shahriar md.Arifur rahman md.Rubel Hassan Zeenath Fardous Muhammed Alamgir Zaman Chowdhury Mohammad Belal Hossain Department of Oceanography Noakhali Science and Technology University Agrochemical and Environmental Research Division Institute of Food and Radiation Biology Atomic Energy Research Establishment 5. Department of Fisheries and Marine Science Noakhali Science and Technology University Department of Environmental Science and Disaster Management Noakhali Science and Technology University University of South Bohemia in Ceske Budejovice Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Research Institute of Fish Culture and Hydrobiology

Sediment samples were collected from ten selected sites of the lower Meghna River estuary, and six heavy metals were analyzed with Atomic Absorption Spectrophotometry(AAS) to assess the contamination level and the metals’ association with sediment grain size. The current results revealed that the mean concentrations of the studied metals were ranked in descending order of iron(Fe)(1.29 ? 103 mg/kg) > zinc(Zn)(42.41 mg/kg) > lead(Pb)(12.48 mg/kg) > chromium(Cr)(10.59 mg/kg) > copper(Cu)(6.22 mg/kg) > cadmium(Cd)(0.28 mg/kg). The geo-accumulation, contamination, and pollution load indexes suggested that the lower Meghna river estuary was not contaminated by Fe, Zn, Pb, Cr, and *** mean size of the sediment ranged from 28.92 to 126.2 mm, and the Pearson correlation coefficient showed a significant association between Fe and Pb(coefficient of determination, r2? 0.836; p < 0.05),and no significant correlation was found between individual metals and grain size, indicating no or low influence on the metals distribution.

关键词： Metal pollution Pollution load index Grain size Trace metals

Distribution of heavy metals in water and sediment of an urban river in a developing country:A probabilistic risk assessment

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International Journal of Sediment Research 2022年第2期37卷 173-187页

作者： Mir Mohammad Ali Saima rahman md Saiful Islam md Refat Jahan Rakib Shaharior Hossen md Zillur rahman Tapos Kormoker Abubakr M. Idris Khamphe Phoungthong Institute of Disaster Management Khulna University of Engineering and Technology Department of Aquaculture Sher-e-Bangla Agricultural University Department of Urban and Regional Planning Khulna University of Engineering and Technology Department of Soil Science Patuakhali Science and Technology University Department of Fisheries and Marine Science Noakhali Science and Technology University Department of Fisheries Science Chonnam National University Quality Control Chemistry Lab Department of Fisheries Department of Emergency Management Patuakhali Science and Technology University Department of Chemistry College of Science King Khalid University Research Center for Advanced Materials Science (RCAMS) King Khalid University Environmental Assessment and Technology for Hazardous Waste Management Research Center Faculty of Environmental Management Prince of Songkla University

River water and sediment embody environmental characteristics that give valuable eco-environmental *** to rapid industrialization,the aquatic environment of any urban river can be seriously polluted by heavy metals(HMs).The global concern is caused by heavy metal pollution because of its potential harm to aquatic ecosystems and human *** the Bhairab River,Bangladesh,surface sediment concentrations of globally alarming toxic metals such as arsenic(As),chromium(Cr),cadmium(Cd),and lead(Pb) were measured to determine the ecological and human health risks of the riverine *** average As,Cr,Cd,and Pb concentrations in water were 3.55,31.74,1.44,and23.82 μg/L,respectively,and in sediment were 4.13,34.17,1.66,and 25.46 mg/kg,*** the winter,metals in sediment were higher than during the *** most sediment samples,the enrichment factor(EF),contamination factor(CF),geoaccumulation index(I),pollution load index(PLI) of As,Cr,Cd,and Pb indicated moderate *** potential ecological risk(PER) in sediment followed the descending order of Cd> As> Pb> *** contamination level of toxic metals implied that the condition is frightening and probably severely affecting the aquatic ecology of this riverine ecosystem.

关键词： Toxic metals Environmental risk Bioaccumulation Ecological risk Bangladesh

Nanoparticles in mitigating gaseous emissions from liquid dairy manure stored under anaerobic condition

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Journal of Environmental Sciences 2019年第2期31卷 26-36页

作者： Niloy Chandra Sarker Shafiqur rahman md.Saidul Borhan Parthiban Rajasekaran Swadeshmukul Santra Ali Ozcan Agricultural and Biosystems Engineering North Dakota State University NanoScience Technology Center University of Central Florida Burnett School of Biomedical Sciences University of Central Florida Department of Chemistry University of Central Florida Department of Materials Science and Engineering University of Central Florida

A number of mitigation techniques exist to reduce the emissions of pollutant gases and greenhouse gases(GHGs) from anaerobic storage of livestock manure. Nanoparticle(NP)application is a promising mitigating treatment option for pollutant gases, but limited research is available on the mode of NP application and their effectiveness in gaseous emission reduction. In this study, zinc silica nanogel(ZnSNL), copper silica nanogel(CuSNL), and N-acetyl cysteine(NACL) coated zinc oxide quantum dot(Qdot) NPs were compared to a control lacking NPs. All three NPs tested significantly reduced gas production and concentrations compared to non-treated manure. Overall, cumulative gas volumes were reduced by 92.73%–95.83%, and concentrations reduced by 48.98%–99.75% for H_2S, and 20.24%–99.82% for GHGs. Thus, application of NPs is a potential treatment option for mitigating pollutant and GHG emissions from anaerobically stored manure.

关键词： Nanoparticles Greenhouse gas Hydrogen sulfide Anaerobic storage Gaseous reduction

Metamaterial-Based Compact Antenna with Defected Ground Structure for 5G and Beyond

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Computers, Materials & Continua 2022年第5期71卷 2383-2399页

作者： md.Mushfiqur rahman md.Shabiul Islam Mohammad Tariqul Islam Samir Salem Al-Bawri Wong Hin Yong Faculty of Engineering Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangi43600Malaysia Space Science Centre Climate Change InstituteUniversiti Kebangsaan Malaysia(UKM)Bangi43600Malaysia

In this paper,a unit cell of a single-negative metamaterial structure loaded with a meander line and defected ground structure(DGS)is investigated as the principle radiating element of an *** unit cell antenna causes even or odd mode resonances similar to the unit cell structure depending on the orientation of the microstrip feed used to excite the unit ***,the orientation which gives low-frequency resonance is considered *** unit cell antenna is then loaded with a meander line which is parallel to the split bearing side and connects the other two sides orthogonal to the split bearing *** modified structure excites another mode of resonance at high frequency when a meander line defect is loaded on the metallic ground *** parameters of the meander line structure,the DGS shape,and the unit cell are optimized to place these two resonances at different frequencies with proper frequency intervals to enhance the ***,the feed is placed in an offset position for better impedance matching without affecting the bandwidth The compact dimension of the antenna is 0.25λL×0.23λL×0.02λL,whereλL is the free space wavelength with respect to the center frequency of the impedance *** proposed antenna is fabricated and *** results reveal that the modified design gives monopole like radiation patterns which achieves a fractional operating bandwidth of 26.6%,from 3.26 to 4.26 GHz for|S11|<−10 dB and a pick gain of 1.26 dBi is *** addition,the simulated and measured crosspolarization levels are both less than−15 dB in the horizontal plane.

关键词： Split ring resonator(SRR) meander line defected ground structure compact antenna bandwidth enhancement 5G technology

Hydrothermal synthesis of triangular CeCO3OH particles and photoluminescence properties

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Chinese Chemical Letters 2017年第3期28卷 663-669页

作者： md.Hasan Zahir Shamseldin A.Mohamed Mohammad Mizanur rahman Ateeq Ur Rehman Center of Research Excellence in Renewable Energy Research Institute King Eahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Center of Research Excellence in Nanotechnology King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Center of Research Excellence in Corrosion King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Center for Engineering Research King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

Ru/CeO_2[RC] and Ru/CeO_2/ethylene glycol（EG） [RCE] nanoparticles were produced by performing a simple hydrothermal reaction at 200℃ for 24 h and found to have two distinct morphologies. The RC nanoparticles are phase pureCeO_2; triangular highly crystallineCeCO_3OH nanoparticles are formed from the solution containing EG under the same hydrothermal reaction conditions at p H 8.5. EG plays an important role in the formation of the triangularCeCO_3OH nanoparticles. The polycrystallineCeCO_3OH nanoparticles retain their triangular structure even after calcination at 600℃in air but are transformed into a pureCeO_2 phase. The room temperature photoluminescence of the RC and RCE nanoparticles and of RCE calcined at 600℃[RCE-600] was also investigated. It was found that the high crystallinity triangular RCE-600 sample exhibits the highest photoluminescence intensity.

关键词： CeCO_3OH particles Ru/CeO_2 Ethylene glycol Hydrothermal process Luminescence

Geochemistry of subsurface Late Quaternary ironstones in Rajshahi and Bogra Districts, Bangladesh: implications for genetic and depositional conditions

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Acta Geochimica 2019年第3期38卷 404-413页

作者： md.Sazzadur rahman Ismail Hossain Pradip Kumar Biswas md.Abdur Rahim A.S.M.Mehedi Hasan md.Ibrahim Adham Department of Geology and Mining University of Rajshahi Institutes of Mining Mineralogy and Metallurgy (IMMM)BCSIR Department of Disaster Resilience and Engineering Patuakhali Science and Technology University

The present study deals with the geochemistry of Late Quaternary ironstones in the subsurface in Rajshahi and Bogra districts, Bangladesh with the lithological study of the boreholes sediments. Major lithofacies of the studied boreholes are clay, silty clay, sandy clay, fine to coarse grained sand, gravels and sands with(fragmentary) ironstones. The ironstones contain major oxides, Fe_2 O_3*(*total Fe)(avg. 66.6 wt%), SiO_2(avg. 15.3 wt%), Al_2 O_3(avg. 4.0 wt%), MnO(avg. 7.7 wt%), and CaO(avg. 3.4 wt%). These geochemical data imply that the higher percentage of Fe_2 O_3* along with Al_2 O_3 and MnO indicate the ironstone as goethite and siderite, which is also validated by XRD data. A comparatively higher percentage of SiO_2 indicates the presence of relative amounts of clastic quartz and manganese-rich silicate or clay in these rocks. These ironstones also have significant amounts of MnO(avg. 7.7 wt%) suggesting their depositional environments under oxygenated condition. Chemical data of these ironstones suggest that the source rock suffered deep chemical weathering and iron was mostly carried in association with the clay fraction and organic matter. Iron concretion was mostly formed by bacterial build up in swamps and marshes, and was subsequently embedded in clayey *** the coastal environments, the water table fluctuates and goethite and siderite with mud and quartz became dry and compacted to form ironstone.

关键词： Ironstone Geochemistry Goethite Siderite Bangladesh

Biochar potentially enhances maize tolerance to arsenic toxicity by improving physiological and biochemical responses to excessive arsenate

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Biochar 2023年第1期5卷 1222-1242页

作者： md.Mezanur rahman Ashim Kumar Das Sharmin Sultana Protik Kumar Ghosh md.Robyul Islam Sanjida Sultana Keya Minhaz Ahmed Sheikh Arafat Islam Nihad mdArifur rahman Khan Mylea C.Lovell md.Abiar rahman S.M.Ahsan Touhidur rahman Anik Pallavi Fnu Lam-Son Phan Tran Mohammad Golam Mostofa Department of Plant Soil ScienceInstitute of Genomics for Crop Abiotic Stress ToleranceTexas Tech UniversityLubbockTX 79409USA Department of Agroforestry EnvironmentBangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh Institute of Biotechnology and Genetic Engineering(IBGE) Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh Department of Agronomy Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh Plant Pathology Division Bangladesh Rice Research InstituteGazipur 1701Bangladesh Department of Agriculture Bangabandhu Sheikh Mujibur Rahman ScienceTechnology UniversityGopalganj 8100Bangladesh Department of Energy Plant Research Laboratory Michigan State UniversityEast LansingMI 48824USA Plant Resilience Institute Michigan State UniversityEast LansingMI 48824USA Department of Biochemistry and Molecular Biology Michigan State UniversityEast LansingMI 48824USA

Metalloid pollution,including arsenic poisoning,is a serious environmental issue,plaguing plant productivity and quality of life ***,a carbon-rich material,has been known to alleviate the negative effects of environmental pollutants on ***,the specific role of biochar in mitigating arsenic stress in maize remains relatively ***,we elucidated the functions of biochar in improving maize growth under the elevated level of sodium arsenate(Na_(2)AsO_(4),AsV).Maize plants were grown in pot-soils amended with two doses of biochar(2.5%(B1)and 5.0%(B2)biochar Kg^(−1) of soil)for 5 days,followed by exposure to Na_(2)AsO_(4)(’B1+AsV’and’B2+AsV’)for 9 *** plants exposed to AsV only accumulated substantial amount of arsenic in both roots and leaves,triggering severe phytotoxic effects,including stunted growth,leaf-yellowing,chlorosis,reduced photosynthesis,and nutritional imbalance,when compared with control ***,biochar addition improved the phenotype and growth of AsV-stressed maize plants by reducing root-to-leaf AsV translocation(by 46.56 and 57.46%in‘B1+AsV’and‘B2+AsV’plants),improving gas-exchange attributes,and elevating chlorophylls and mineral levels beyond AsV-stressed *** pretreatment also substantially counteracted AsV-induced oxidative stress by lowering reactive oxygen species accumulation,lipoxygenase activity,malondialdehyde level,and electrolyte *** oxidative stress in‘B1+AsV’and‘B2+AsV’plants likely supported by a strong antioxidant system powered by biochar-mediated increased activities of superoxide dismutase(by 25.12 and 46.55%),catalase(51.78 and 82.82%),and glutathione S-transferase(61.48 and 153.83%),and improved flavonoid levels(41.48 and 75.37%,respectively).Furthermore,increased levels of soluble sugars and free amino acids also correlated with improved leaf relative water content,suggesting a better osmotic acclimatization mechanism in biochar-pretreated AsV-exposed plants.

关键词： Arsenic contamination Antioxidant defense system Biochar Gas-exchange attributes Nutrient dynamics Oxidative stress