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Sensing and Uptake of Nitrogen in Rice Plant: A Molecular View

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Rice science 2019年第6期26卷 343-355页

作者： md Saiful islam Department of Soil Science Patuakhali Science and Technology University Graduate School of Agricultural and Life Sciences The University of Tokyo

As a main feature of plant autotrophy, assimilation of inorganic nitrogen (N) is not only of fundamental interest to the crop, but also a crucial factor in crop productivity. N is the main plant mineral nutrient needed for chlorophyll production and other plant cell components (proteins, nucleic acids and amino acids). I highlighted the novel aspects of N responsive sensors, transporters and signaling molecules recently identified in the monocot rice plant, and discussed their potential roles in N sensing and transporting. Furthermore, over the last couple of years, N sensing has been shown to be affected by different external factors, which act as local signals to trigger systemic signaling coordinated by long-distance transport or mobile signals in plant body. Understanding of this complex regulatory network provides a foundation mechanism for the development of novel strategies to increase the acquisition and transportation efficiency of nitrogen under varying N conditions for rice production.

关键词： rice nitrate signaling gene function

MOVPE Growth of In_xGa_(1-x)N(x～0.4) and Fabrication of Homo-junction Solar Cells

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Journal of Materials Science & Technology 2013年第2期29卷 128-136页

作者： md. Rafiqul islam md. Rejvi Kaysir md. Jahirul islam A. Hashimoto A. Yamamoto Department of Electrical and Electronic Engineering KUETKhulna 9203 Bangladesh Graduate School of Engineering University of Fukui 3-9-1 BunkyoFukui 910-8507 Japan

The metal organic vapor phase epitaxy （MOVPE） growth of indium gallium nitride （InGaN） has been discussed in detail towards the fabrication of solar cell. The InGaN film with In contents up to 0.4 are successfully grown by controlling the fundamental growth parameters such as the precursor gas flow rates, temperature etc. The formation of metallic In originates from the higher value （0.74） of trimethylindium/ （trimethylindium ＋ triethylgallium）（TMI/（TMI ＋ TEG）） molar ratio with low （4100） V/lll weight molar ratio while the lower value （0.2） of TMI/（TMI ＋ TEG） causes the phase separation. It is also necessary to control the growth rate and epitaxial film thickness to suppress the phase separation in the material. The crystalline quality of grown films is studied and it is found to be markedly deteriorated with increasing In content. The lattice parameters as well as the thermal expansion coefficient mismatch between GaN template and InGaN epi-layer are primarily considered as the reasons to deteriorate the film quality for higher In content. By using Ino.16Ga0.84N films, an n＋-p homo-junction structure is fabricated on 0.65 μm GaN template. For such a device, the response to the light illumination （AM 1.5） is observed with an open circuit voltage of 1.4 V and the short circuit current density of 0.25 mA/cm2. To improve the performance as well as increase solar photon capturing, the device is further fabricated on thick GaN template with higher In content. The In0.25Ga0.75N n＋-p junction solar cell is found better performance with an open circuit voltage of 1.5 V and the short circuit current density of 0.5 mA/cm2. This is the InGaN p-n homo-junction solar cell with the highest In content ever reported by MOVPE.

关键词： InGaN Metal organic vapor phase epitaxy (MOVPE) Growth Film quality Doping p-n junction

Mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

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Chinese Physics B 2017年第3期26卷 395-403页

作者： A K M Farid UI islam md Nurul Huda Liton H M Tariqul islam md Al Helal md Kamruzzaman Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and Materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China

First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and Mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.

关键词： BiVO4 crystal structure lone pair mechanical stability

A New Algorithm for a Condenser Design for Large-Scale Nuclear Power Plants in Tropical Region

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Journal of Thermal Science 2020年第5期29卷 1370-1389页

作者： KHAN Abid Hossain islam md.Shafiqul Department of Industrial and Production Engineering Jashore University of Science and TechnologyJashore 7408Bangladesh Department of Nuclear Engineering University of DhakaDhaka 1000Bangladesh

This work presents a new velocity search algorithm for designing a condenser of a 1200 MWe large-scale nuclear power plant situated in tropical *** this,the condenser pressure was considered in the range of 7.5-15 kPa while its tube inner diameter was taken as 28 mm with 1 mm tube wall *** longitudinal and transverse condensers with multiple shell tanks and varied shell tank lengths from 8-14 m have been considered in this *** different tertiary coolant temperature rises were chosen as 4°C,8°C and 12°C by considering tropical region average reservoir water temperature range of 28°C to 32°C during *** of tertiary coolant was kept within 0.75-1.5 m/s to ensure sufficient turbulence to avoid erosion-corrosion of the *** simulation has been employed to obtain tube-side pressure drop and convection heat transfer coefficient directly from tertiary coolant inlet velocity using κ-ω turbulent flow model.A new iterative“Velocity-search algorithm”has been developed that focuses on finding the correct tertiary coolant velocity instead of overall heat transfer *** revealed that velocity-search algorithm yielded very close to the important physical and thermal parameters of condenser compared to the existing design data in large scale nuclear power ***-search algorithm has given less number of condenser design physical parameters that meets the velocity acceptance criteria for longitudinal condenser compared to the transverse ***,velocity-search algorithm is found to be more reliable,robust,and consistent for condenser design compared to the conventional design algorithm used in Log-Mean Temperature Difference method.

关键词： nuclear power plant vacuum condenser velocity-search algorithm tropical region

Antitumor activity of Aponogeton undulatus against Ehrilich ascites carcinoma in Swiss albino mice

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 431-438页

作者： md Reyazul islam md BadrulAlam UmmeTamima Shayla islam Jenny Department of Bioactive Materials Science Chonbuk National University567Baekje-daeroDeokjin-guJeonju-siJeollabuk-doRepublic of Korea Graduate School of Food Science & Biotechnology Kyungpook National University 80Daehak-raBuk-guDaeguRepublic of Korea Department of Pharmacy Atishlipankar University of Science & Technology College of Pharmacy Seoul National UniversityI Guanak-roGuanak-guSeoulRepublic of Korea

Objective:To investigate in vitro antioxidant and in vivo antitumor activity of the crude methanolic extract of Aponogeton undulatus(MAU) along with its various organic ***:Aponogeton undulatus leaves were successively extracted using methanol(MAU)and then fractionated by chloroform,ethyl acetate(EAU) and *** total antioxidant capacity,lipid peroxidation inhibition assay.1.1-diphenyl-2-picrylhydrazyl(DPPH) free radical scavenging assay and ferrous reducing power assessment were used to evaluate the antioxidant potential of the crude extract and its organic *** in vivo antitumor activity is evaluated against Ehrlich ascites carcinoma(EAC) cell bearing in Swiss albino ***:EAU showed the highest antioxidant capacity as(175.80±0.41)mg/g,IC_(50)value of DPPH scavenging activity was(38.84±0.02)μg/mL and also exhibited maximum lipid peroxidation inhibition activity with the IC_(50) value of(42.52±0.32)μg/mL than other *** results demonstrate that reducing power of the extract was concentration *** addition,EAU was administered at 50.100 and 200 mg/kg body weight respectively to EAC cell bearing mice and a significant(P<0.05)decrease in tumor volume,packed cell volume and viable cell count and also increased the life span(17.52% .42.53% and 62.05% ).Hematological profiles were restored to normal levels in MAU treated mice as compared to EAC control ***:The results were found to be significant and confirmed that the Aponogeton undulatus has remarkable antitumor activity with antioxidant potential.

关键词： Antioxidant Antitumor Ehrlich ascites carcinoma Aponogeton undulatus

The Dauki Fault at the Shillong Plateau-Bengal Basin Boundary in Northeastern India:2D Finite Element Modeling

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Journal of Earth Science 2012年第6期23卷 854-863页

作者： md Shofiqul islam Ryuichi Shinjo Faculty of Science University of the RyukyusOkinawa 903-0213Japan Department of Petroleum and Mining Engineering Shahjalal University of Science and TechnologySylhet 3114Bangladesh

The Dauki fault is a major fault along the southern boundary of the Shillong plateau that may be a source of destructive seismic hazards for the adjoining areas, including northeastern Bangladesh. In this study, we simulated the present stress distribution and the ongoing convergence deformation within the study area using numerical simulation. This simulation attempts to deter- mine the proper dip angle of the Dauki fault from a variety of differently established models but with the same realistic boundary conditions. The simulated stress field helped to predict the type of tec- tonic environment and the faulting patterns of the study area. The best-fit model can account for the compressive stress regime in the study area, except in the uppermost part of the Shillong plateau, the Bengal basin, and Assam areas where extensional stress regimes exists. In the model, the elements for which Mohr-Coulomb＇s failure occurs correspond with the observed earthquake data that refer to the Dauki fault as a north-dipping thrust fault.

关键词： Dauki fault Bengal basin tectonic stress earthquake.

Characterization of ^(68)Zn uptake,translocation,and accumulation into developing grains and young leaves of high Zn-density rice genotype

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第5期12卷 408-418页

作者： md.Jahidul islam SHOHAG MOE Key Lab of Environmental Remediation and Ecosystem Health College of Environmental and Resource SciencesZhejiang University

Zinc(Zn) is an essential micronutrient for humans,but Zn deficiency has become serious as equally as iron(Fe) and vitamin A deficiencies *** and breeding of high Zn-density crops is a suitable,cost-effective,and sustainable way to improve human ***,the mechanism of high Zn density in rice grain is not fully understood,especially how Zn transports from soil to *** experiments were carried out to compare Zn uptake and distribution in two different Zn-density rice genotypes using stable isotope *** seedling stage,IR68144 showed higher 68Zn uptake and transport rate to the shoot for the short-term,but no signifi-cant difference was observed in both genotypes for the *** in xylem sap of IR68144 was consistently higher,and IR68144 exhibited higher Zn absorption ratio than IR64 at sufficient(2.0 μmol/L) or surplus(8.0 μmol/L) Zn supply ***64 and IR68144 showed similar patterns of 68Zn accumulation in new leaves at seedling stage and in de-veloping grains at ripening stage,whereas 68Zn in new leaves and grains of IR68144 was consistently *** results suggested that a rapid root-to-shoot translocation and enhanced xylem loading capacity may be the crucial processes for high Zn density in rice grains.

关键词： Zinc Stable isotope High Zn-density rice genotype Translocation Remobilization

Typhoon parameter sensitivity of storm surge in the semi-enclosed Tokyo Bay

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Frontiers of Earth Science 2020年第3期14卷 553-567页

作者： md.Rezuanul islam Hiroshi Takagi School of Environment and Society Tokyo Institute of TechnologyTokyo152-8550Japan

In this study,a storm surge model of the semi-enclosed Tokyo Bay was constructed to investigate its hydrodynamic response to major typhoon parameters,such as the point of landfall,approach angle,forward speed,size,and *** typhoon simulation was validated for Typhoon Lan in 2017,and 31 hypothetical storm surge scenarios were generated to establish the sensitivity of peak surge height to the variation in typhoon *** maximum storm surge height in the upper bay adjacent to the Tokyo Metropolitan Area was found to be highly sensitive to the forward speed and size of the passing ***,the importance of these parameters in disaster risk reduction has been largely overlooked by researchers and disaster *** was also determined that of the many hypothetical typhoon tracks evaluated,the slow passage of a large and intense typhoon transiting parallel to the longitudinal axis of Tokyo Bay,making landfall 25 km southwest,is most likely to cause a hazardous storm surge scenario in the upper-bay *** results of this study are expected to be useful to disaster managers for advanced preparation against destructive storm surges.

关键词： storm surge risk semi-enclosed bay typhoon parameters parametric study Typhoon Lan

Improved voltage tracking of autonomous microgrid technology using a combined resonant controller with lead-lag compensator adopting negative imaginary theorem

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Protection and Control of Modern Power Systems 2022年第1期7卷 149-164页

作者： md.Yah-Ya Ul Haque md.Rashidul islam Tanvir Ahmed md.Rafiqul islam Sheikh Department of Electrical and Electronic Engineering Varendra UniversityRajshahi 6204Bangladesh Department of Electrical and Electronic Engineering Rajshahi University of Engineering&TechnologyRajshahi 6204Bangladesh

Growing application of distributed generation units at remote places has led to the evolution of microgrid(MG)*** an MG system functions independently,i.e.,in autonomous mode,unpredictable loads and uncertainties emerge throughout the *** obtain stable and flexible operation of an autonomous MG,a rigid control mechanism is *** this paper,a robust high-performance controller is introduced to improve the performance of voltage tracking of an MG system and to eliminate stability problems.A combination of a resonant controller and a lead-lag compensator in a positive position feedback path is designed,one which obeys the negative imaginary(NI)theorem,for both single-phase and three-phase autonomous MG *** controller has excellent tracking *** is investigated through considering various uncertainties with different load *** feasibility and effectiveness of the controller are also determined with a comparative analysis with some well-known controllers,such as linear quadratic regulator,model predictive and NI approached resonant *** confirms the superi-ority of the designed controller.

关键词： Negative imaginary theorem Resonant controller Lead-lag compensator Autonomous microgrid Voltage tracking