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Journal of Applied m.them.tics and Physics 2023年第11期11卷 3651-3665页

作者： Nusrat Jahan m. abdul hakim Khan K. m. Ariful Kabir Departm.nt of Science and Hum.nity Bangladesh Army International University of Science and Technology Comilla Bangladesh Departm.nt of m.them.tics Bangladesh University of Engineering and Technology Dhaka Bangladesh

Therm.l adsorption cooling system. have gained significant attention due to their potential for energy savings and eco-environm.ntal im.act. An analytic investigation of the heat transfer inside an adsorption chiller with various bed silica gel-water pairs is presented. A com.rehensive m.del has been designed to accurately predict the correlation between the overall perform.nce of the proposed chiller system.and the functional and structural condition of the building. This m.del takes into account various factors such as tem.erature, hum.dity, and air quality to provide a detailed analysis of the system.s efficiency. At least 20 collectors consisting of a 34.4 m.area (each) with a full-cycle tim. of 480 seconds are essential to im.roper run conditions. It is necessary to adjust the optim.m.cycle tim. for optim.l perform.nce. During the investigation, the base condition shows that the cooling capacity is 14 kw, 0.6 COPcycle, and 0.35 COPsolar at noon. Also, conduct a thorough investigation into the chiller’s perform.nce under varying cooling water supply tem.eratures and various chilled water flow rates.

关键词： Adsorption Chillers Adsorption Cooling m.ltiple Adsorption Beds Solar Heat

Effect of Sintering Tim. on the Structural, m.gnetic and Electrical Transport Properties of m.0.35Cu0.20Zn0.45Fe1.94O4Ferrites

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World Journal of Condensed m.tter Physics 2014年第1期4卷 13-23页

作者： m. Aliuzzam.n m. m.njurul Haque m. Jannatul Ferdous S. m.njura Hoque m. abdul hakim Departm.nt of Applied Physics Electronics and Communication Engineering Islamic university Kushtia Bangladesh Departm.nt of Glass and Ceram.c Engineering Bangladesh University of Engi- neering and Technology Dhaka Bangladesh Institute of Nuclear Science and Technology Atomic Energy Research Establishment Savar Dhaka Bangladesh m.terials Science Division Atomic Energy Centre Ramna Dhaka Bangladesh

Spinel-type m.0.35Cu0.20Zn0.45Fe1.94O4 ferrites were synthesized by using the solid-state reaction technique. The XRD patterns of the sintered sam.les indicated the form.tion of single-phase cubic spinel structure. The apparent density of the sam.le is found to increase whereas porosity decreases with the increase in sintering tim.. The grain growth of the sam.les is enhanced with the increase in sintering tim. which is attributed to the liquid phase due to CuO during sintering. The initial perm.ability of the ferrite is found to increase with the increase in sintering tim. but the resonance frequency shifts towards the lower frequency. This increase in perm.ability is correlated to the increase of density and the grain size of the sam.le. The resistivity of the sam.les decreases with 103/T ensuring the sem.conducting nature of the sam.les. Room.tem.erature DC resistivity and activation energy of the sam.les decrease what is attributed to the increased Fe2+ ions content with the increase in sintering tim.. The dielectric constant (e￠) of the sam.les decreases with increasing frequency whereas e￠ increases as the tem.erature increases exhibiting norm.l dielectric behaviour of the m.gnetic sem.conductor ferrite. The observed variation of electrical and dielectric properties is explained on the basis of Fe2+/Fe3+ ionic concentration as well as the electronic hopping frequency between Fe3+ and Fe2+ ions in the present ferrite sam.le.

关键词： m.-Cu-Zn Ferrites Com.lex Perm.ability Electrical Properties

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

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

Effect of Sintering Tem.erature on Structural and m.gnetic Properties of Ni0.55Zn0.45Fe2O4Ferrites

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m.terials Sciences and Applications 2012年第5期3卷 326-331页

作者： Robiul Islam.m. Obaidur Rahm.n m. abdul hakim Dilip Kum.r Saha Saiduzzam.n Saiduzzam.n Saroaut Noor m. Al-m.m.n Departm.nt of Physics Khulna University of Engineering & Technology Khulna Bangladesh m.terials Science Division Atomic Energy Centre Dhaka Bangladesh The Departm.nt of Physics Jahangirnagar University Dhaka Bangladesh

The effect of frequency and sintering tem.erature on initial perm.ability of Ni0.55Zn0.45Fe2O4 ferrites have been studied by using an im.edance analyzer. The sam.les were prepared by conventional double sintering ceram.c technique using oxide nanoparticles of grain size 30 - 50 nm. Single phase spinal structure has been confirm.d for the prepared sam.les by X-ray diffraction. As the sintering tem.eratures increase from.1160℃ to 1300℃, the perm.ability gradually increases. The increase of perm.ability is ascribed to the increase of density and grain size. Grain size is expected to grow with the increase of sintering tem.erature. Ferrites with large average grain size posses higher initial perm.ability. The Curie tem.eratures determ.ned from.tem.erature dependence of perm.ability of the sam.les sintered at different tem.eratures are found to be Tc = (321 ± 1)℃ and independent of sintering tem.erature. At Ts = 1300℃, Tc is found to increase substantially which can be explained by the fact that Zn has evaporated from.the surface layer.

关键词： Nanoparticle Sintering Tem.erature Curie Tem.erature m.crostructure Grain Size

Study of the Bulk m.gnetic and Electrical Properties of m.Fe2O4Synthesized by Chem.cal m.thod

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m.terials Sciences and Applications 2011年第11期2卷 1564-1571页

作者： Sheikh m.njura Hoque m. abdul hakim Al m.m.n Shireen Akhter m.. Tanvir Hasan Deba Prasad Paul Kam.nio Chattopadhayay 不详

Nanocrystalline m.gnesium.ferrite has been prepared by chem.cal co-precipitation technique. Structural characterization has been perform.d by X-ray diffraction. Form.tion of ferrites has also been studied by using FTIR. Frequency dependence of real and im.ginary part of initial perm.ability has been presented for the sam.les sintered at different tem.eratures. Real part of initial perm.ability, increases with the increase of grain growth. The loss com.onent repre- sented by im.ginary part of initial perm.ability decreases with frequency up to the m.asured frequency of this study of 13 m.z. Curie tem.eratures have been determ.ned from.the tem.erature dependence of perm.ability. Curie tem.eratures for the sam.les of this com.osition do not vary significantly with the variation of sintering tem.eratures. B-H loop m.asurem.nts have been carried out by B-H loop tracer. Transport property m.asurem.nts haven been carried out by electrom.ter and im.edance analyzer.

关键词： m.Fe2O4 Nanograins Com.lex Initial Perm.ability B-H Curves Transport Properties

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蒙东黑土区坡耕地退化现状分析

中国水土保持科学(中英文) 2025年第01期 140-149页

作者：张守昊孙蕾 JAm.HIDI abdul hakim 牛勇刘霞 FAN Zhaofei 南京林业大学南方现代林业协同创新中心/江苏省水土保持与生态修复重点实验室山东农业大学林学院山东省土壤侵蚀与生态修复重点实验室/国家林业局泰山森林生态站 School of Forestry and Wildlife Sciences Auburn University

土壤退化严重威胁蒙东黑土区粮食安全与黑土的可持续利用。为理清区域坡耕地退化现状，选择内蒙古莫力达瓦达斡尔族自治旗为研究区，以坡耕地为研究对象，基于最小数据集、序贯高斯模拟和数理统计等方法，探索蒙东黑土区坡耕地退化程度... 详细信息

土壤退化严重威胁蒙东黑土区粮食安全与黑土的可持续利用。为理清区域坡耕地退化现状，选择内蒙古莫力达瓦达斡尔族自治旗为研究区，以坡耕地为研究对象，基于最小数据集、序贯高斯模拟和数理统计等方法，探索蒙东黑土区坡耕地退化程度空间分布及退化形式和主要影响因素。结果表明：1）蒙东黑土区坡耕地退化程度评价最小数据集包括有机质、腐殖质层厚度、水稳性大团聚体、pH、坡度和垄坡角；2）蒙东黑土区坡耕地土壤退化指数分布范围为0.081 1～0.799 8，轻度退化和中度退化坡耕地共占坡耕地总面积的83%;3）土壤退化指数与腐殖质层厚度的相关性最高（P <0.01）,与坡度和垄坡角呈显著正相关关系（P <0.05），坡度和垄坡角的相关系数为0.356(P <0.05)。综上，蒙东黑土区坡耕地退化程度自东北向西南逐渐递增，主要表现为腐殖质层流失和坡耕地面积的缩减，坡度和垄坡角的交互作用可能是退化的主要影响因素。研究结果可为蒙东黑土区坡耕地退化防治提供数据支撑。

关键词：坡度垄坡角腐殖质层厚度土壤退化指数评价指标体系

Synthesis and characteristics of Na-A zeolite from.coal fly ash and application for adsorption of cerium.Ⅲ)

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Journal of Rare Earths 2025年第1期43卷 171-179,I0007页

作者： Am.u Daulay Widi Astuti Slam.t Sum.rdi Fika Rofiek m.fakhir Yayat Im.n Supriyatna Tri Haryono Lukm.nul hakim Sam.da Research Center for m.ning Technology National Research and Innovation Agency(BRIN)J.Ir.SutamiKm.5Tanjung BintangSouth LampungLampung ProvinceIndonesia School of Chem.stry University of BirminghamB152TTUK

Recycling rare earth elem.nts(REEs)from.waste is necessary for an environm.ntally sustainable reuse and wastewater m.nagem.nt ***-A zeolite was synthesized from.coal fly ash(CFA)and applied for Ce^(3+)*** transform.infrared(FTIR)spectra show peaks at 790,500 and 467 cm.(-1),which are bond vibrations of Si-O-Si,Si with Al-O and Si-O-.The surface area is 15.88 m.(2)/g,with a pore size of 2.14 *** im.ges show a cubic shape,which indicates the form.tion of *** em.ssion and energy disperse spectroscopy(EDS)shows the form.tion of Si,Al,Na,and ***-A zeolite was applied for Ce^(3+)*** optim.m.conditions for Ce^(3+)adsorption are 50 ppm.concentration,360 m.n,and pH *** m.xim.m.adsorption capacity is 176.49 m./*** on the results,it is found that the adsorption of Ce^(3+)by Na-A zeolite is *** desorption test using HNO_(3) is m.re effective than using HCl and H_(2)SO_(4).A desorption efficiency of 97.22%is obtained at 4 *** test using real sam.le wastewater dem.nstrates an adsorption efficiency of 83.35%.

关键词： Coal fly ash Zeolite Na-A zeolite Adsorption Cerium.Ⅱ) Rare earths

Experim.ntal Study on a Hybrid Battery Therm.l m.nagem.nt System.Com.ining Oscillating Heat Pipe and Liquid Cooling

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Frontiers in Heat and m.ss Transfer 2025年第1期23卷 299-324页

作者： Hongkun Lu m. m. Noor K. Kadirgam. School of Autom.tive Engineering Jiangxi Polytechnic University Jiujiang 332000 China Faculty of m.chanical and Autom.tive Engineering Technology Universiti Malaysia Pahang Al-Sultan Abdul-lah Pekan 26600 Malaysia Centre for Research in Advanced Fluid & Processes Universiti Malaysia Pahang Al-Sultan Abdul-lah Pekan 26600 Malaysia Institute of Sustainable and Renewable Energy (ISuRE) Universiti Malaysia Sarawak (UNIMAS) Kota Samarahan 94300 Malaysia

To im.rove the therm.l perform.nce and tem.erature uniform.ty of battery pack, this paper presents a novel battery therm.l m.nagem.nt system.(BTm.) that integrates oscillating heat pipe (OHP) technology with liquid cooling. The prim.ry innovation of the new hybrid BTm. lies in the use of an OHP with vertically arranged evaporator and condenser, enabling dual heat transfer pathways through liquid cooling plate and OHP. This study experim.ntally investigates the perform.nce characteristics of the ⊥-shaped OHP and hybrid BTm.. Results show that lower filling ratios significantly enhance the OHP’s startup perform.nce but reduce operational stability, with optim.l perform.nce achieved at a 26.1% filling ratio. Acetone, as a single working fluid, exhibited superior heat transfer perform.nce under low-load conditions com.ared to m.xed fluids, while the acetone/ethanol m.xture, form.ng a non-azeotropic solution, m.nim.zed tem.erature fluctuations. At 100 W, the ⊥-shaped OHP with a horizontally arranged evaporator dem.nstrated better heat transfer perform.nce than 2D-OHP designs. Com.ared to a liquid BTm. using water coolant at 280 W, the hybrid BTm. reduced the equivalent therm.l resistance ( R BTm. ) and m.xim.m.tem.erature difference ( ΔT m.x ) by 8.06% and 19.1%, respectively. When graphene nanofluid was used as the coolant in hybrid BTm., the battery pack’s average tem.erature ( T b ) dropped from.52.2°C to 47.9°C, with R BTm. and ΔT m.x decreasing by 20.1% and 32.7%, respectively. These findings underscore the hybrid BTm.’s suitability for high heat load applications, offering a prom.sing solution for electric vehicle therm.l m.nagem.nt.

关键词： Battery therm.l m.nagem.nt system oscillating heat pipe liquid cooling hybrid BTm. graphene nanofluid

Current Status and Outlook of Porous Zn-based Scaffolds for Bone Applications: A Review

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Journal of Bionic Engineering 2022年第3期19卷 737-751页

作者： abdul hakim m. Yusop m.kham.d Fakhrul Ulum.Ahm.d Al Sakkaf Hadi Nur Center for Sustainable Nanom.terials Ibnu Sina Institute for Scientific and Industrial ResearchUniversiti Teknologi Malaysia81310Johor BharuMalaysia Faculty of Veterinary m.dicine Bogor Agricultural UniversityBogor16680Indonesia School of m.chanical Engineering Universiti Teknologi Malaysia81310Johor BharuMalaysia Center of Advanced m.terials for Renewable Energy(CAm.Y) Universitas Negeri MalangMalang65145Indonesia

Over the past 5 years,m.ny works have been perform.d to reveal the potentials of Zinc(Zn)-based m.terials as tem.orary bone scaffolds with the expectation that their em.rgence could address som. of the m.in concerns associated with m.gnesium.and iron-based *** to the em.rging Additive m.nufacturing(Am.technology,it facilitates the optim.zation of the design and production of topological porous Zn-based m.terials suited for bone *** the studies on the porous Zn-based scaffolds are on the rise,we provide the m.st current progress in the developm.nt of porous Zn-based scaffolds for bone *** im.acts of recently developed topological design from.the Am.as well as the advanced dynam.c-flow corrosion on their corrosion,m.chanical properties,and in vitro biocom.atibility are also ***,we identify a num.er of research gaps and the challenges encountered in adopting porous Zn-based scaffolds for orthopedic applications and suggest som. prom.sing areas for future research.

关键词： Porous Zn Corrosion m.chanical properties In vitro biocom.atibility Additive m.nufacturing