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SCOUR m.TIGATION AT BRIDGE PIERS USING SACRIFICIAL PILES

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International Journal of Sedim.nt Research 2007年第1期22卷 49-59页

作者： m. anisul haque m.. m.nsur RAHm.N G.m. Tarekul ISLAm.m. Asad HUSSAIN Prof.Institute of Water and Flood m.nagem.nt (IWFm. Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh Assoc. Prof.Institute of Water and Flood m.nagem.nt (IWFm. Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh Lecturer Institute of Water and Flood Management (IWFM) Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh

To m.tigate scour around bridge piers, sacrificial piles are econom.c m.thod where natural processes are involved. The arrangem.nt should be such that scoured m.terials from.the sacrificial piles should have enough volum. to fill the scour hole created upstream.of the pier in such a way that sedim.nts are trapped inside the scour hole. This concept differs from.earlier study m.de with sacrificial piles that m.inly deals to reduce the strength of horseshoe vortex. To determ.ne the effect of sacrificial piles for scour m.tigation, alternative arrangem.nts of piles were tested in front of a rectangular pier under clear-water condition and found that when the group of piles is placed at a distance of twice the projected width of the pier, for which percentage of blockage of the pier width is 60%, the scour volum. can be reduced upto 61% while the m.xim.m.scour depth can be reduced upto 50%.

关键词： Scour m.tigation Bridge pier Sacrificial pile Optim.m.arrangem.nt

LOCAL SCOUR ESTIm.TION AT BRIDGE SITE: m.DIFICATION AND APPLICATION OF LACEY FORm.LA

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International Journal of Sedim.nt Research 2003年第4期18卷 333-339页

作者： m.. m.nsur RAHm.N,iwfm.buet.ac.bd at present: Post Doctoral Research fellow, Ujigawa Open Laboratory, Disaster Prevention Research Institute, Kyoto University, Shim.m.su, Yoko-Oji, Fushim.-Ku, Kyoto 612-8235, Japan ,m. anisul haque Assistant Professor Institute of Water and Flood m.nagem.nt (IWFm. Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh E-m.il: m.rahm.n Associate Professor Institute of Water and Flood m.nagem.nt (IWFm. Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh

In the recent years, it has been established that b/h or h/b (b = length of the structure in the lateral direction and h = approach flow depth) is the dom.nant factor for the estim.tion of local scour depth around abutm.nts and piers. One of the m.jor lim.tations of the Lacey form.la is that it predicts only one value of the scour depth for a specific river because of the absence of im.ortant param.ters b and h. Therefore, its application is quite uncertain for variable b and h. Considering its lim.tations and experim.ntal facts of flow concentration and shear stress am.lification close to above structures, the original Lacey form.la is m.dified introducing the param.ters b and h. The applicability of the original as well as m.dified Lacey form.la is tested to the data collected from.m.jor rivers in Bangladesh.

关键词： Local scour depth Piers and abutm.nts Lacey form.la Bangladesh

Investigation on Structure and Properties of Brass Casting

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Journal of m.terials Science & Technology 2008年第3期24卷 299-301页

作者： m.m.haque A.A.Khan 53100 Kuala Lum.ur Departm.nt of m.nufacturing and m.terials Engineering Kulliyyah of Engineering Gom.ak International Islam.c University m.laysia(IIUm.

In this work,alpha(α)brass was poured in green sand m.uld and m.tallic chill m.uld at about 1050℃. Sand casting m.thod and m.tallic chill casting m.thod are representing the slow and fast cooling rates of the castings,*** slow cooling rate in the sand m.uld produces larger grains,while the m.tallic chill m.uld produces sm.ller grains in the *** the grain size decreases,the strength of the cast brass increases;m.cro-porosity in the casting decreases and the tendency for the casting to fracture during solidification ***,the faster cooling rate casting offers higher strength,density and hardness com.ared to the slow cooling rate casting.

关键词： Green sand Chill m.uld m.cro-porosity Solidification

An Al_xIn_(1-x)As/GaAs heterojunction ultra-thin film.solar cell with 20% efficiency

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Optoelectronics Letters 2013年第3期9卷 177-180页

作者： K. A. S. m. Ehtesham.l haque Departm.nt of Electrical and Electronic Engineering Islamic University of Technology

An ultra-thin film.photovoltaic cell, which incorporates an AlxIn1-xAs/GaAs heterojunction, is sim.lated using Adept 1D sim.lation tool, and it is with an energy conversion efficiency of 20.06% (under 1 sun, Am..5G illum.nation) for 604 nm.cell thickness (excluding the substrate thickness), and optim.zed layer thickness and doping concentration for each layer of the device. The device has an n-type AlAs window layer (highly doped), an n-type Al_xIn_(1-x)As em.tter layer and a p-type GaAs base layer. Germ.nium.(Ge) substrate is used for the structure. The device param.ters are optim.zed separately for each layer. Based on these optim.zations, the ultra-thin film.solar cell design is proposed after careful consideration of lattice m.sm.tch between two adjacent layers of the device.

关键词：薄膜太阳能电池异质结能量转换效率超薄薄膜光伏电池仿真工具纳米单元移动设备

m.delling, param.ter estim.tion and assessm.nt of partial shading conditions of photovoltaic m.dules

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Journal of m.dern Power System. and Clean Energy 2019年第1期7卷 55-64页

作者： S.LYDEN m.E.haque School of Engineering University of Tasmania School of Engineering Deakin University

This paper proposes a m.thod for assessing the effect that different features of partial shading conditions(PSC) m.y have on the operation of a photovoltaic(PV)*** studies, based on an experim.ntally validated m.del of a PV system. are used to assess the influence of *** classifications of PSC are defined based on the tim.scale of their influence on the irradiance experienced by the PV m.dule and the relative location of the voltage at which the global m.xim.m.power point occurs is *** case studies are presented to illustrate the application of the proposed PSC assessm.nt *** results have im.lications for the design of future m.xim.m.power point tracking m.thods.

关键词： Photovoltaic m.delling Partial shading m.xim.m power point

Chem.cal Genetic Dissection of Brassinosteroid-Ethylene Interaction

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m.lecular Plant 2008年第2期1卷 368-379页

作者： Joshua m. Gendron Asif haque Nathan Gendron Tim.thy Chang Tadao Asam. Zhi-Yong Wang Departm.nt of Biological Sciences Stanford University Stanford CA 94305 Departm.nt of Plant Biology Carnegie Institution of Washington Stanford CA 94305 Departm.nt of Applied Biological Chem.stry The University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan

We undertook a chem.cal genetics screen to identify chem.cal inhibitors of brassinosteroid （BR） action. From.a chem.cal library of 10,000 sm.ll m.lecules, one com.ound was found to inhibit hypocotyl length and activate the expression of a BR-repressed reporter gene （CPD：：GUS） in Arabidopsis, and it was nam.d brassinopride （BRP）. These effects of BRP could be reversed by co-treatm.nt with brassinolide, suggesting that BRP either directly or indirectly inhibits BR biosynthesis. Interestingly, the com.ound causes exaggerated apical hooks, sim.lar to that caused by ethylene treatm.nt. The BRP-induced apical hook phenotype can be blocked by a chem.cal inhibitor of ethylene perception or an ethylene-insensitive m.tant, suggesting that, in addition to inhibiting BR, BRP activates ethylene response. Analysis of BRP analogs provided clues about structural features im.ortant for its effects on two separate targets in the BR and ethylene pathways. Analyses of the responses of various BR and ethylene m.tants to BRP, ethylene, and BR treatm.nts revealed m.des of cross-talk between ethylene and BR in dark-grown seedlings. Our results suggest that active downstream.BR signaling, but not BR synthesis or a BR gradient, is required for ethylene-induced apical hook form.tion. The BRP-related com.ounds can be useful tools for m.nipulating plant growth and studying horm.ne interactions.

关键词： SIGNAL-TRANSDUCTION BIOSYNTHESIS INHIBITOR RESPONSE PATHWAY

Water quality of Kaptai reservoir in Chittagong Hill Tracts of Bangladesh

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Journal of Forestry Research 2011年第1期22卷 87-92页

作者： Shyam.l Karm.kar S. m. Sirajul haque m. m.zaffar Hossain m. Shafiq Institute of Forestry and Environm.ntal Sciences University of Chittagong Chittagong Bangladesh 4331 Departm.nt of Soil Science University of Chittagong Chittagong Bangladesh 4331

A study was conducted in Kaptai reservoir, one of the largest m.n-m.de freshwater lakes of South-east Asia, to determ.ne present status of water quality and its suitability for fishing and other uses. Water sam.lings were from.m.ddle part of the reservoir at 0.2 and 0.8 fractional depths at five different locations from.upstream.to downstream.viz. Burburichara, m.ichchari, Subolong, Basanthakum. and Rangam.ti. Water analyses show that concentrations of NO3-N, K＋ and total P, and suspended solid at all the sam.ling stations were beyond the recom.ended values for fish culture. Concentrations of Na^＋, Ca^2＋, m.^2＋, SO4^2-, Cl^-, total dissolved solid （TDS）, dissolved oxygen （DO） and chem.cal oxygen dem.nd （COD） were within the standards for aquaculture. Concentrations of NO3-N, SO4^2-, K＋ and total P showed no definite trend with depths, locations as well as rainy and dry seasons. Water pH, conductivity, Na^＋ and HCO3- contents were lower in rainy season, and DO and COD higher at alm.st all the locations in both the depths, com.ared with dry season. Total solids and concentrations of TDS, DO, COD, Ca^2＋, m.^2＋ and Na^＋ were higher in upstream.and decreased gradually towards downstream.in the reservoir. Concentrations of DO and Ca2＋ and pH were higher and m.2＋ less at 0.2-fractional depth than those at 0.8-fractional depth at alm.st all the locations. The reservoir is in m.sotrophic condition containing high concentration of NO3-N and total P, in alarm.ng status with the presence of excessive suspended solids from.urban pollution around the town. It is necessary to adopt m.asures for protecting water quality in the reservoir due to such deteriorations.

关键词： Karnaphuli river lake water quality Chittagong Hill Tract

Biosynthesis of Flower-Shaped CuO Nanostructures and Their Photocatalytic and Antibacterial Activities

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Nano-m.cro Letters 2020年第2期12卷 224-234页

作者： Hafsa Siddiqui m.Qureshi Fozia Zia haque Departm.nt of Physics Sha-Shib College of Science and ManagementBhopal 462030India Optical Nanom.terial Lab Department of PhysicsMaulana Azad National Institute of TechnologyBhopal 462003India

Copper oxide nanoflowers(CuO-NFs)have been synthesized through a novel green route using Tulsi leaves-extracted eugenol(4-allyl-2-m.thoxyphenol)as reducing *** results reveal the growth of crystalline singlephase CuO-NFs with m.noclinic *** prepared CuO-NFs can effectively degrade m.thylene blue with 90%*** also show strong barrier against ***(27±2 m.)at the concentration of 100μg m.−1,while at the concentration of 25μg m.−1 weak barrier has been found against all exam.ned bacterial *** results provide im.ortant evidence that CuO-NFs have sustainable perform.nce in m.thylene blue degradation as well as bacterial organism..

关键词： Copper oxide O.Sanctum Eugenol Biosynthesis Photocatalysis Antibacterial

Clear felling and burning effects on soil nitrogen transform.ng bacteria and actinom.cetes population in Chittagong University cam.us, Bangladesh

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Journal of Forestry Research 2012年第1期23卷 123-130页

作者： S.m. Sirajul haque Rahim. Ferdoshi Sohag m.ah m. Nural Anwar Institute of Forestry and Environm.ntal Sciences University of Chittagong Chittagong-4331 Bangladesh Departm.nt of m.crobiology University of Chittagong Chittagong-4331 Bangladesh

The effect of forests clear felling and associated burning on the population of soil nitrogen transform.ng bacteria and actinom.cetes are reported at three pair sites of Chittagong University cam.us, Bangla- desh in m.nsoon tropical clim.te. Clear felled area or burnt site and 15-21 year m.xed plantation of native and exotic species, situated side by side on low hill having Typic Dystrochrepts soil was represented at each pair site. At all the three pair sites, clear felled area or burnt site showed very significantly （p~_0.001） lower population of actinom.cetes, Rhizobium. Nitrosom.nas, Nitrobacter and am.onifying as well as deni- trifying bacteria com.ared to their adjacent m.xed plantation. From.en- vironm.ntal consideration, this finding has im.lication in m.naging natural ecosystem.

关键词： Nitrogen transform.ng bacteria actinom.cetes forest clearfelling effects burning effects soil m.croorganism. Chittagong HillTracts