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Time-Dependent Cylindrical and Spherical Solitary Structures and Double Layers of Dust Ion-Acoustic Waves in Ultra-Relativistic Dense Plasma

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Communications in Theoretical Physics 2013年第6期59卷 745-750页

作者： T.Akhter m.m.hossain A.A.mamun Department of Physics Jahangirnagar University

Cylindrical and spherical (nonplanar) solitary waves (SWs) and double layers (DLs) in a multi-ion plasma system (containing inertial positively as well as negatively charged ions, non-inertial degenerate electrons, and negatively charged static dust) are studied by employing the standard reductive perturbation method. The modified Gardner (mG) equation describing the nonlinear propagation of the dust ion-acoustic (DIA) waves is derived, and its nonplanar SWs and DLs solutions are numerically analyzed. The parametric regimes for the existence of SWs, which are associated with both positive and negative potential, and DLs which are associated with negative potential, are obtained. The basic features of nonplanar DIA SWs, and DLs, which are found to be different from planar ones, are also identified.

关键词： solitary waves double layers ultra-relativistic dense plasma dust ion acoustic waves Gardnerequation

Clonal propagation of Bambusa vulgaris by leafy branch cuttings

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Journal of Forestry Research 2011年第3期22卷 387-392页

作者： m.S. Islam m.K. Bhuiyan m. m. hossain m.A. hossain Institute of Forestry and Environmental Sciences University of Chittagong Chittagong-4331 Bangladesh

Bambusa vulgaris Schrad ex wendl is a widely cultivated bamboo species in rural Bangladesh for its versatile uses. The vegetative propagation becomes the only viable alternative for this species because B. vulgaris does not set seed after sparse flowering, which makes seedling progenies unavailable. A low-cost propagation trial was conducted to explore the clonal propagation techniques for the species with two types of small branch cuttings, nodal leafy cuttings and tip cuttings. The cuttings, after treating with 0, 0.1%, 0.4%, and 0.8% IBA solutions, were kept in non-mist propagator to let them to root for assessing the rooting ability. The cuttings were rooted in four weeks and were allowed to grow in the polybags for 10 months under nursery condition to assess their steckling capacity. The study reveals that both types of branch cuttings are able to develop roots, shoots, to survive and to form rhizome under the nursery condition. Rooting ability of the cuttings was significantly enhanced by the application of rooting hormone - IBA. The highest rooting percentage in nodal leafy cuttings and the tip cuttings （56.67% and 51.0%, respectively） were observed in 0.8% IBA treatment, followed by 0.4% IBA and the lowest （34.3% and 30.0%, respectively） was in control. The highest number of root developed per cutting （9.77 and 8.33 in nodal leafy cuttings and the tip cuttings, respectively） was also obtained from the cuttings treated with 0.8% IBA solution, followed 0.4% IBA treatment and the lowest （3.1 and 2.1, respectively） was in the cuttings without treatment. However, the length of the longest root varied significantly neither with the cutting types nor the concentrations of IBA solution. Survival percentage of the stecklings in nursery condition was significantly enhanced by IBA.

关键词： Bambusa vulgaris leafy branch cuttings non-mist propagator rooting ability steckling capacity

Application of In-Flight melting Technology by RF Induction Thermal Plasmas to Glass Production

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Plasma Science and Technology 2008年第3期10卷 344-347页

作者：姚耀春 m.m.hossain T.WATANABE F.FUNABIKI T.YANO National Engineering Laboratory of Vacuum metallurgy Kunming University of Science and Technology Kunming 650093 China Department of Environmental Chemistry and Engineering Tokyo Institute of Technology Yokohama 226-8502 Japan Department of Environmental Chemistry and Engineering Tokyo Institute of TechnologyYokohama 226-8502 Japan Department of Chemistry and materials Science Tokyo Institute of Technology Tokyo 152-8550 Japan

An innovative in-flight glass melting technology with induced thermal plasmas was developed for the purpose of energy conservation and environmental protection. Two-dimensional modeling was used to simulate the thermofluid fields in the plasma torch. The in-flight melting behavior of glass raw material was investigated by various analysis methods. Results showed that the plasma temperature was up to 10000 K with a maximum velocity over 30 m/s, which made it possible to melt the granulated glass raw material within milliseconds. The carbonates in the raw material decomposed completely and the compounds in the raw material attainted 100% vitrification during the in-flight time from the nozzle exit to substrate. The particle melting process is similar to the unreacted-core shrinking model.

关键词： induced thermal plasmas in-flight melting plasma heat transfer glass production

Cylindrical and spherical Gardner solitons and double layers in a dusty electronegative non-thermal plasma with two-temperature electrons

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Chinese Physics B 2013年第7期22卷 339-345页

作者： T. Akhter m. m. hossain A. A. mamun Department of Physics Jahangirnagar University Department of Electrical and Electronic Engineering Bangladesh University of Business and Technology

A precise theoretical investigation has been made on the cylindrical and spherical （nonplanar） Gardner solitons （GSs） and double layers （DLs） in a dusty electronegative plasma （composed of inertial positive and negative ions, maxwellian cold electrons, non-thermal hot electrons, and negatively charged static dust）. The reductive perturbation method has been used in derivation of the modified Gardner （mG） equation describing the nonlinear propagation of the dust ion-acoustic （DIA） waves. The mG equation admits solitary waves （SWs） and DLs solutions for σ around its critical value σ c （where σc is the value of σ corresponding to the vanishing of the nonlinear coefficient of the Korteweg de-Vries （K-dV） equation）. The nonplanar SWs and DLs solutions are numerically analyzed and the parametric regimes for the existence of the positive as well as negative SWs and negative DLs are obtained. The basic features of nonplanar DIA SWs and DLs, which are found to be different from planar ones, are also identified. The implications of our results to different space and laboratory dusty plasma situations, are discussed.

关键词： electronegative plasma two-temperature electrons Garner solitons double layers

Furrow design for improving crop establishment of two-wheel tractor operated strip tillage planters in loam and clay loam soils

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 130-139页

作者： m.Arshadul Hoque m.m.hossain A.T.m.Ziauddin Timothy J.Krupnik mahesh K.Gathala Senior Scientific Officer FMP Engineering DivisionBangladesh Agricultural Research InstituteGazipur-1701Bangladesh Department of Farm Power and machinery Bangladesh Agricultural UniversityMymensingh-2202Bangladesh International maize and Wheat Improvement Center-Bangladesh Dhaka-1213Bangladesh

Conservation agriculture(CA)based production systems may help in achieving more sustainable intensification of cropping systems that use less labour and energy and have higher profit margins,in addition to soil conservation and environmental impact mitigation *** these objectives can only be achieved when the right mechanization options,including appropriate crop establishment equipment,are in place to assist in timely field *** urgent need exists,therefore,to fine tune and re-adjust the existing two-wheel tractor(2WT)operated seed drills,with specific reference to the design of blade and furrow openers,while at the same time considering performance in different soil types and *** this end,experiments were conducted during 2013-2014 and 2014-2015 at two BARI Regional Agricultural Research Stations in Jamalpur and Barisal,Bangladesh,on a loam and clay loam soil,respectively,to evaluate five types of furrow opener for strip *** and modified shoe-type furrow openers were tested and compared with three inverted-T furrow openers with rake angles of 75°,65°and 55°.The newly designed inverted-T furrow openers were narrower than the shoe-type openers;they also had a longer,hollow shanks and provided better options for adjustment to achieve the desired seeding depth and line *** to shoe-type openers,better seeding depth,uniformity and higher degree of seed coverage were recorded with use of the inverted-T furrow opener with a 65°rake *** resulted in better seed coverage in the furrow,a higher emergence rate index,and the highest emergence percentage of maize and mung *** research findings can be generalized to smallholder production systems on loam and clay loam soils where farmers utilize 2WT operated seed drills for crop establishment in both traditional and conservation agriculture-based planting systems.

关键词： two-wheel tractor strip tillage planter inverted-T furrow opener rake angle conservation agriculture emergence percentage

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.D.hossain m.S.Sikder m.N.I.Khan m.R.Rahman Physics Discipline Khulna UniversityKhulna9208Bangladesh Department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EDX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EDX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EDX Resistivity

Acceleration of microtuber Induction in Potato by Cytokinine and Photoperiod Adjustment

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中国马铃薯 2003年第5期17卷 257-261页

作者： m F Alam N Ahsan m m hossain S Parvez A m Swaraz R Islam Department of Botany University of RajshahiDepartment of Botany University of RajshahiDepartment of Botany University of RajshahiDepartment of Botany University of RajshahiDepartment of Botany University of RajshahiDepartment of Botany University of Rajshahi Rajshahi-6205. Bangladesh Rajshahi-6205. Bangladesh Rajshahi-6205. Bangladesh Rajshahi-6205. Bangladesh Rajshahi-6205. Bangladesh Rajshahi-6205. Bangladesh

Protocol was developed for acceleration of microtuber induction in potato. It was observed that cytokinine (Kin), and both dark and light period had great influence on in vitro tuberization. Regarding concentration of Kin, 8 mg/l was found excellent for microtuber induction and formation under both dark and light conditions. Under continuous dark condition, higher percentage of explants (shoot) induced microtuber was observed than the short and long period of light conditions. For increasing the number and weight of microtuber product/explant, use of long photoperiod (16 h) is recommended.

关键词：马铃薯微型薯光周期调节外植体激素

Radiation effects on opto-electrical properties of polyimide and polyimide fluorocarbon sandwitch polymer film.

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Radiation effects on opto-electrical properties of polyimide...

用于纺织品表面永久改性的工业真空等离子体技术

4th International Symposium on Engineering Plastics

作者： m.m.hossain T.K.Gooder Rojina Akter Department of Applied Physics ＆ Electronic Engineering Rajshahi UniversityRajshahiBangladesh

＜正＞Now a day,polymer is widely used in nano technology in the field of conducting polymer nanowires,encapsulation,nanoelectronics,nanofibers,nanobrushes.A technique for preparing nearly aligned nanotubes from a wid...

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国际纺织导报 2016年第5期44卷 46-46,48-50页

作者： R.Alam K.m.G.hossain C.Grabher m.m.hossain 黄明罗艳 Grabher等离子仿生公司奥地利赛发集团瑞士

通过等离子体处理,合成材料(如涂覆聚氨酯的聚酯或聚酰胺)表面的黏附性得以显著提高。研究还表明:通过聚合物和非聚合物形成的气体混合物引入极性基团,可显著改善材料的亲水耐久性;且可聚合性气体,如CH_4,C_2H_2,C_2H_4及其混合物,或诸... 详细信息

通过等离子体处理,合成材料(如涂覆聚氨酯的聚酯或聚酰胺)表面的黏附性得以显著提高。研究还表明:通过聚合物和非聚合物形成的气体混合物引入极性基团,可显著改善材料的亲水耐久性;且可聚合性气体,如CH_4,C_2H_2,C_2H_4及其混合物,或诸如丙烯酸、硅氧烷等一些液体单体,对织物表面永久性亲水、防油和防污改性方面发挥着重要的作用。

关键词：离子体处理纺织品永久改性涂层