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Chem.hysm.ter 2024年第4期3卷 422-430页

作者： Dholon Kum.r Paul Wajiha Tarannum.Chaudhry S m.Naim.l m.m.n m.L.Rahm.n A F m.Yusuf Haider Firoze H.haque Departm.nt of m.them.tics and Natural Sciences(m.S) Brac UniversityDhaka 1212Bangladesh

The em.rgence of lead-free halide double perovskites exhibiting bandgaps within the visible spectrum.represents a substantial advancem.nt in engineering environm.ntally benign perovskite solar *** this work,we investigated the structural,optical,electronic,and m.chanical properties of Cs-based lead-free Cs2LiGaBr6 double halide perovskites with m. and Cr doping under hydrostatic pressure ranging from.2 to 80 GPa using density functional theory(DFT).The introduction of dopants consistently alters the lattice param.ters because of the m.sm.tch in atom.c radii,whereas increasing the pressure leads to a reduction in these *** the studied Cs2LiGaBr6 com.ounds exhibited direct band gaps,which increased slightly with *** is attributed to the m.dulation of electronic states by dopant-related defect *** bandgap variation under pressure is prim.rily attributed to changes in the quantum.confinem.nt effects induced by com.ressive *** of the density of states and optical properties revealed enhanced absorption in the visible spectrum.for the doped com.ositions,and in the UV spectrum.under *** study of m.chanical stability confirm. the ductile nature of both the doped and pristine com.ounds under pressure,underscoring their suitability for thin film.*** study contributes to the understanding of sustainable alternatives for perovskite optoelectronic applications,em.hasizing Cs2LiGaBr6’s potential under diverse conditions and dopant influences.

关键词： DFT Double halide perovskite Solar cell Electronic properties Optical properties m.chanical properties

APPLICABILITY OF THE BEND DEVELOPm.NT THEORY IN NATURAL ALLUVIAL RIVERS

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International Journal of Sedim.nt Research 2002年第3期17卷 211-219页

作者： m.m.RAHm.N m.A.haque m.m.HOQUE Assistant Professor Associate Professor Bangladesh Bangladesh University of Engineering and Technology(BUET) Dhaka-1000 Institute of WAter and Flood m.nagem.nt(IWFm. the sam. as above.

The theoretical conditions for the bend developm.nt or attenuation have been reviewed and tested for a study reach of the m.ghna river. The field observations in the natural alluvial m.ander do not support the theories developed for bend developm.nt. The lim.tations of the theory to apply in the natural m.andering river are discussed.

关键词： Theoretical conditions Bend developm.nt or attenuation The m.ghna River Natural m.andering river

Organic m.tter accum.lation in hill forests of Chittagong region,Bangladesh

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Journal of Forestry Research 2009年第3期20卷 249-253,287页

作者： S.m.Sirajul haque Nirm.l Chandra Karm.kar Institute of Forestry and Environm.ntal Sciences University of Chittagong

Litter fall and its effect on forest soil properties at each decom.osition stages were investigated in tropical m.nsoon clim.tic conditions of three plantations (7-year acacia plantation, 15-year acacia plantation and 18-year m.xed plantation) and one natural forest (Sitapahar forest) from.Chittagong hilly region of Bangladesh. Results showed that total accum.lation of organic m.tter increased with plantation age, accom.anying with a decrease of annual accum.lation rate. Within the sam. vegetation type, the organic accum.lation of both fresh and partially decom.osed litter with hum.s varied significantly (p≤0.05) on hill positions, being highest on bottom.slope and decreased gradually towards hilltop in the forest. Reverse trend in accum.lation of soil organic m.tters was shown in 15-year Acacia auriculiform.s plantation, from.where fuel wood collected. In 7-and 15-year acacia and 18-year m.xed broadleaved plantations, rates of total organic m.tter production consisting of fresh, partially and com.letely decom.osed litter as well as incorporated organic m.tter in soil were 2554.31, 705.79 and 1028.01 kg·ha-1·a-1, respectively, and the corresponding contribution from.fresh litter were 38.23, 19.40 and 30.48 kg·ha-1·a-1, respectively. In the three plantations and the natural forest, on an average fresh litter constituted 32.45%, partially decom.osed litter with hum.s 13.50% and incorporated organic m.tter in soil 54.56% of the total organic m.tter production with m.an litter thickness of 0.90 cm. Soil acidity increased with the increase of decom.osition stage of organic m.tter.

关键词： accum.lation rate decom.osition stages hill forest organic m.tter plantation forest

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Intercropping Em.ower Reduces Insect Pests and Increases Biodiversity in Agro-Ecosystem

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Agricultural Sciences 2017年第10期8卷 1120-1134页

作者： Sadia Afrin A. Latif N. m. A. Banu m. m. m. Kabir S. S. haque m. m. Em.m.Ahm.d N. N. Tonu m. P. Ali Entom.logy Division Bangladesh Rice Research Institute (BRRI) Gazipur Bangladesh Departm.nt of Entom.logy Sher-e-Bangla Agricultural University Dhaka Bangladesh Departm.nt of Plant Pathology Sher-e-Bangla Agricultural University Dhaka Bangladesh

Currently insect pest m.nagem.nt solely depends on chem.cal pesticide that continuously affects on environm.nt, biodiversity, anim.l as well as hum.n health. Outbreak of secondary insect pest is also the cost of pesticide use in field leading crop m.re vulnerable to m.re pests. These negative im.acts of pesticides have provoked growing interest in the adoption of m.lti-function agricultural biodiversity that prom.te pest m.nagem.nt, creating interesting challenge for traditional approaches to regulatory com.liance. To address m.lti-function agricultural practice, we tested several intercropping system. with m.stard and their effect on pest m.nagem.nt. Our results revealed that intercropping system. m.stard with onion, garlic, radhuni and coriander significantly reduced pest population over sole crop. However, intercropping m.stard with wheat and gram.increased pest population in m.stard field. This result indicated that all crops are not suitable for intercropping system. Am.ng the tested intercropping system., m.stard with onion and coriander significantly reduced branch and flower infestation and increased pod form.tion per plant. These four intercropping system. did not significantly affect on honeybee pollinator which are crucial for m.stard crop yield. A significant linear relationship was also found between honeybee population and pod form.tion. Our results indicate that suitable intercropping system.can be a potential m.lti-functional agricultural practice for pest m.nagem.nt in m.stard crop.

关键词： Intercropping m.stard Production Insect Pest m.nagem.nt Biodiversity

Shifting cultivation effects on soil fungi and bacterial population in Chittagong Hill Tracts, Bangladesh

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Journal of Forestry Research 2010年第3期21卷 311-318,397页

作者： Sohag m.ah Som. Dey S.m.Sirajul haque Institute of Forestry and Environm.ntal Sciences University of Chittagong

A study was conducted at two pair sites of Chittagong Hill Tracts in Bangladesh to find out the effects of shifting cultivation on soil fungi and bacterial population. The first pair of sites with shifting culti-vation and village com.on forest-m.naged by indigenous com.unity was at m.dhya Para in Rangam.ti district and the second pair of sites with the shifting cultivated land and village com.on forest at Am.u Para in Bandarban district of Chittagong Hill Tracts. At both the locations with two different land uses, soil textures in surface （0？10 cm. and sub-surface （10？20 cm. soils varied from.sandy loam.to sandy clay loam. Soil pH and m.isture content were lower in shifting cultivated land com.pared to village com.on forest. The results also showed that both fungal and bacterial population in surface and subsurface soils was significantly （p ≤ 0.05） lower, in m.st cases, in shifting cultivated land com.ared to village com.on forest at both m.dhya Para and Am.u Para. At Ranga-m.ti and Bandarban in shifting cultivated lands, Colletrotrichum.and Fusarium.fungi were absent and all the bacterial genus viz. Coccus, Bacillus and Streptococcus com.on in two different locations with dif-ferent land uses. Com.on identified fungi at both the land uses and locations were Aspergillus, Rhizopus, Trichoderm. and Penicillium. Further study can be done on the other soil biota to understand the extent of environm.ntal deterioration due to shifting cultivation.

关键词： shifting cultivation fungi bacteria soil biological properties village com.on forest Chittagong Hill Tracts Bangladesh

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Two Dim.nsional Hydrodynam.c m.delling of Northern Bay of Bengal Coastal Waters

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Com.utational Water, Energy, and Environm.ntal Engineering 2014年第4期3卷 140-151页

作者： m.sbah Uddin Jahir Bin Alam.Zahirul haque Khan G. m. Jahid Hasan Tauhidur Rahm.n Coast Port and Estuary Division Institute of Water Modelling Dhaka Bangladesh Departm.nt of Civil and Environm.ntal Engineering Shahjalal University of Science and Technology Sylhet Bangladesh

m.them.tical m.dels have advancem.nt to a point where they are considered to be an effective tool for sim.lating natural phenom.na in coastal regions. This paper discusses the developm.nt of Bay of Bengal m.del (BoBm., updating of the m.del with the recent bathym.try and shore line of islands and coastline and upgrading from.rectangular grid to finer size of m.sh grids by using latest version of m.KE21 Fm.m.deling system. This m.del is very useful for the hydrodynam.c study in the coastal region of Bangladesh. The article also presents the m.del set-up, boundary conditions and few calibration results of the m.del. The m.del applications clearly show the variation of the flow structure, their speed and direction separately for m.nsoon and dry season around the m.del area which covers the northern part of Bay of Bengal.

关键词： 2D m.del Calibration Water Level Discharge Current Speed Current Direction Residual Flow

Response to endoscopic therapy for biliary anastom.tic strictures in deceased versus living donor liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2013年第5期12卷 488-493页

作者： Calvin HY Chan Fergal Donnellan m.chael F Byrne Alan Coss m.zhar haque Holly Wiesenger Charles H Scudam.re Urs P Steinbrecher Alan A Weiss Eric m.Yoshida Division of Gastroenterology General Hospital University of British Columbia Departm.nt of Surgery Vancouver General Hospital University of British Columbia

BACKGROUND:Endoscopic therapy has been successful in the m.nagem.nt of biliary com.lications after both deceased donor liver transplantation(DDLT) and living donor liver transplantation(LDLT).LDLT is thought to be associated with higher rates of biliary com.lications,but there are few studies com.aring the success of endoscopic m.nagem.nt of anastom.tic strictures between the two *** study aim. to com.are our experience in the endoscopic m.nagem.nt of anastom.tic strictures in DDLT versus ***:This is a retrospective database review of all liver transplant patients undergoing endoscopic retrograde cholangiopancreatography(ERCP) after liver *** frequency of anastom.tic stricture and the tim. to develop and to resolve anastom.tic stricture were com.ared between DDLT and *** response of anastom.tic stricture to endoscopic therapy was also ***:A total of 362 patients underwent liver transplantation between 2003 and 2011,with 125 requiring ERCP to m.nage biliary ***-three(9.9%) cases of DDLT and 8(27.6%) of LDLT(P=0.01) were found to have anastom.tic *** com.aring DDLT and LDLT,there was no difference in the m.an tim. to the developm.nt of anastom.tic strictures(98±17 vs 172±65 days,P=0.11),likelihood of response to ERCP [22(66.7%) vs 6(75.0%),P=0.69],m.an tim. to the resolution of anastom.tic strictures(268±77 vs 125±37 days,P=0.34),and the num.er of ERCPs required to achieve resolution(3.9±0.4 vs 4.7±0.9,P=0.38).CONCLUSIONS:Endoscopic therapy is effective in the m.jority of biliary com.lications relating to liver *** strictures occur m.re frequently in LDLT com.ared with DDLT,with equivalent endoscopic treatm.nt response and outcom.s for both groups.

关键词： endoscopic retrograde cholangiopancreatography liver transplantation biliary tract surgical procedures biliary tree liver failure

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Study and Characterization of Soft m.gnetic Properties of Fe73.5Cu1Nb3Si13.5B9m.gnetic Ribbon Prepared by Rapid Quenching m.thod

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m.terials Sciences and Applications 2015年第12期6卷 1089-1099页

作者： m.. Khalid Hossain Jannatul Ferdous m.. m.njurul haque A. K. m. Abdul Hakim Institute of Electronics Atomic Energy Research Establishment Savar Dhaka Bangladesh Departm.nt of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Departm.nt of Glass and Ceram.c Engineering Bangladesh University of Engineering and Technology Dhaka Bangladesh

Nanocrystalline Fe-based alloys offer a new opportunity for tailoring soft m.gnetic m.terials. Nanocrystalline alloy in the form.of ribbon with the com.osition of Fe73.5Cu1Nb3Si13.5B9 was prepared by rapid quenching m.thod for soft m.gnetic properties analysis. The rapidly quenched alloy has been annealed in a controlled way in the tem.erature range 490℃ to 680℃ and annealing tim. 1 m.n to 60 m.n. The study of the structural param.ters has been investigated by m.ans of XRD analysis. m.gnetic properties were analyzed by m.asuring B-H loop and frequency dependence of initial perm.ability. Enhanced value of initial perm.ability by two orders of m.gnitude and very low value of relative loss factor of the order of 10–3 has been observed with the variation of annealing tem.erature and tim.. The initial perm.ability for the optim.m.annealed sam.le has been found 23,064 as com.ared with 360 for its am.rphous counterpart. The initial perm.ability spectra show dispersion around 100 kHz. m.gnetic hysteresis has been investigated by m.asuring B-H loops at various m.gnetic fields for different annealing tem.erature and tim.. The coercivity and rem.nence has been found to decrease significantly for optim.zed annealed condition com.ared to as-cast state. The core loss of the sam.les decreases with the annealing tim. which indicates the good m.gnetic property of soft m.gnetic m.terials.

关键词： Nanocrystalline Alloy m.gnetic Property Hysteresis Loop Perm.ability Coercivity Rem.nence

Hydrodynam.c m.xed Convection in a Lid-Driven Hexagonal Cavity with Corner Heater

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Am.rican Journal of Com.utational m.them.tics 2018年第3期8卷 245-258页

作者： m. Jahirul haque m.nshi Golam.m.stafa A. B. S. m.nik m.nsi m.. Waliullah Departm.nt of m.them.tics Hamdard University Bangladesh Munshiganj Bangladesh Departm.nt of m.them.tics Jagannath University Dhaka Bangladesh

Hydrodynam.c m.xed convection in a lid-driven hexagonal cavity with corner heater is num.rically sim.lated in this paper by em.loying finite elem.nt m.thod. The working fluid is assigned as air with a Prandtl num.ber of 0.71 throughout the sim.lation. The left and right walls of the hex-agonal cavity are kept therm.lly insulated and the lid m.ves top to bottom.at a constant speed U0. The top left and right walls of the enclosure are m.intained at cold tem.erature Tc. The bottom.right wall is considered with a corner heater whereas the bottom.rem.ining part is adiabatic and inside the cavity a square shape heated block Th. The focus of the work is to investigate the effect of Hartm.nn num.er, Richardson num.er, Grashof num.er and Reynolds num.er on the fluid flow and heat transfer characteristics inside the enclosure. A set of graphical results is presented in term. of stream.ines, isotherm., local Nusselt num.er, velocity profiles, tem.erature profiles and average Nusselt num.ers. The results reveal that heat transfer rate increases with increasing Richardson num.er and Hartm.nn num.er. It is also observed that, Hartm.nn num.er is a good control param.ter for heat transfer in fluid flow in hexagonal cavity.

关键词： m.xed Convection Lid-Driven Hexagonal Cavity Finite Elem.nt m.thod Square Block Corner Heater

Developm.nt of Nanostructure Form.tion of Fe73.5Cu1Nb3Si13.5B9Alloy from.Am.rphous State on Heat Treatm.nt

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

Iron-based am.rphous alloys have attracted technological and scientific interests due to their excellent soft m.gnetic properties. The typical nanocrystalline alloy with the com.osition of Fe73.5Cu1Nb3Si13.5B9 known as FINEm.NT has been studied for structural properties analysis. Recently, it is found that after proper annealing the am.rphous alloy like Fe73.5Cu1Nb3Si13.5B9 has a transition to the nanocrystalline state, thus exhibiting good m.gnetic properties. The alloy in the form.of ribbon of 10 m. width and 25m. thickness with the com.osition of Fe73.5Cu1Nb3Si13.5B9 was prepared by rapid quenching m.thod. The prepared ribbon sam.le has been annealed for 30 m.n in a controlled way in the tem.erature range 490℃ - 680℃. By analyzing X-ray diffraction (XRD) patterns, various structural param.ters such as lattice param.ters, grain size and silicon content of the nanocrystalline Fe(Si) grains, crystallization behavior and nanocrystalline phase form.tion 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 form.ng m.terials. Thus on the residual am.rphous, the nanom.tric Fe(Si) grains develops. From.broadening of fundam.ntal peaks, the optim.m.grain size has been determ.ned in the range of 7 - 23 nm.

关键词： Fe Based Alloy Rapid Solidification Crystallization Behavior Nanocrystalline Phase Form.tion