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71.
The Earth to air heat exchanger (EAHE) is an effective passive cooling and heating system for buildings. This paper studied numerically the potential for reduction in energy consumption for cooling and heating loads for a residence equipped with an EAHE system in the climate of Nasiriya city, which is located in southern Iraq and at 31.7°N and 45.8°E, latitude and longitude, respectively. Also, this paper presents a study about the thermal performance of three types of EAHE systems, system 1, consisting of one layer of EAHE and buried at an available area of house garden with 3‐m depth, system 2, at the same site of system 1, but with two layers of EAHE at two depths, 3 and 4 m, and finally, system 3, buried along the area of the house at a depth of 3 m. First, the built numerical model was validated against experimental results, and the results of the comparison showed good agreement. The electricity consumption for cooling and heating of the house is calculated with and without the EAHE system. The results showed that with using EAHE, there is a considerable saving in energy and saving in the cost of electricity consumption, which reached 376 329 IQD ($301.11) over 1 year for system 2. 相似文献
72.
Mirjavadi Seyed Sajad Afshari Behzad Mohasel Barati Mohammad Reza Hamouda A. M. S. 《Microsystem Technologies》2019,25(8):3137-3150
Microsystem Technologies - Nonlinear free/forced vibration of a functionally graded graphene nanoplatelet (GNP) reinforced microbeam having geometrical imperfection which is rested on a non-linear... 相似文献
73.
Mohamamd Hasan Khoshgoftar Manesh Sajad Khamis Abadi Majid Amidpour Hooman Ghalami Mohammad Hosein Hamedi 《Korean Journal of Chemical Engineering》2013,30(4):796-812
A new procedure for environmental targeting of co-generation system is presented. The proposed method is based on the concepts of pinch technology for total site targeting of fuel, power, steam, environmental impacts and total annualized cost with considering emissions taxes. This approach provides a consistent, general procedure for determining mass flow rates and efficiencies of the applied turbines. This algorithm utilizes the relationship of entropy with enthalpy and isentropic efficiency. Also, the life cycle assessment (LCA) as a well-known tool for analyzing environmental impacts on a wide perspective with reference to a product system and the related environmental and economic impacts have been applied. In this regard, a damage-oriented impact analysis method based on Eco-indicator 99 and footprints analysis was considered. In addition, the present work demonstrates the effect of including both sensible and latent heating of steam in the extended Site Utility Grand Composite Curve (ESUGCC). It is shown that including sensible heating allows for better thermal matching between the processes. Furthermore, the other representation YSUGCC as the other form of Site Utility Grand Composite has been proposed. Two case studies were used to illustrate the usefulness of the new environmental targeting method. 相似文献
74.
Plants, being sessile, face an array of biotic and abiotic stresses in their lifespan that endanger their survival. Hence, optimized uptake of mineral nutrients creates potential new routes for enhancing plant health and stress resilience. Recently, minerals (both essential and non-essential) have been identified as key players in plant stress biology, owing to their multifaceted functions. However, a realistic understanding of the relationship between different ions and stresses is lacking. In this context, ionomics will provide new platforms for not only understanding the function of the plant ionome during stresses but also identifying the genes and regulatory pathways related to mineral accumulation, transportation, and involvement in different molecular mechanisms under normal or stress conditions. This article provides a general overview of ionomics and the integration of high-throughput ionomic approaches with other “omics” tools. Integrated omics analysis is highly suitable for identification of the genes for various traits that confer biotic and abiotic stress tolerance. Moreover, ionomics advances being used to identify loci using qualitative trait loci and genome-wide association analysis of element uptake and transport within plant tissues, as well as genetic variation within species, are discussed. Furthermore, recent developments in ionomics for the discovery of stress-tolerant genes in plants have also been addressed; these can be used to produce more robust crops with a high nutritional value for sustainable agriculture. 相似文献
75.
76.
Sajad Hussain Chuanbao Cao Ghulam Nabi Waheed S. Khan Zahid Usman Tariq Mahmood 《Electrochimica acta》2011,56(24):8342
Cu2O/ZnO p–n heterojunction solar cells were fabricated by rf sputtering deposition of n-ZnO layer, followed by electrodeposition of p-Cu2O layer. The different electrodeposition potentials were applied to deposit Cu2O on ZnO. The particle size, crystal faces, crystallinity of Cu2O is important factor which determine the p–n junction interface and consequently their effect on the performance of the heterojunction solar cell. It is observed that at −0.6 V, p-Cu2O film generates fewer surface states in the interband region due to the termination of [1 1 0] resulting in higher efficiency (0.24%) with maximum particle size (53 nm). The bandgap of Cu2O at this potential is found to be 2.17 eV. Furthermore, annealing of ZnO film was performed to get rid of deteriorating one and two dimensional defects, which always reduce the performance of solar cell significantly. We found that the solar cell performance efficiency is nearly doubled by increasing the annealing temperature of ZnO thin films due to increasing electrical conductance and electron mobility. Doping studies and fine tuning of the junction morphology will be necessary to further improve the performance of Cu2O/ZnO heterojunction solar cells. 相似文献
77.
Nader Pourmahmoud Sajad Rezazadeh Iraj Mirzaee Vahid Heidarpoor 《Journal of Mechanical Science and Technology》2011,25(10):2665-2673
A full three-dimensional, non-isothermal computational fluid dynamics model of a proton exchange membrane fuel cell (PEMFC)
with both the gas distribution flow channels and the membrane electrode assembly (MEA) has been developed. A single set of
conservation equations which are valid for the flow channels, gas-diffusion electrodes, catalyst layers, and the membrane
region are developed and numerically solved using a finite volume based computational fluid dynamics technique. In this research
some parameters such as Oxygen consumption and fuel cell performance according to the variation of porosity, thickness of
gas diffusion layer, and the effect of the boundary conditions were investigated in more details. Numerical results shown
that the higher values of gas diffusion layer porosity improve the mass transport within the cell, and this leads to reduce
the mass transport loss. The gas diffusion layer thickness affects the fuel cell mass transport. A thinner gas diffusion layer
increases the mass transport, and consequently the performance of the fuel cell. Furthermore, the study of boundary conditions
effects showed that by insulating the bipolar surfaces, hydrogen and oxygen consumption at the anode and cathode sides increase;
so that the fuel cell performance would be optimized. Finally the numerical results of proposed CFD model are compared with
the available experimental data that represent good agreement. 相似文献
78.
Fallah Davoud Abbasinezhad Raad Mohammad Rezazadeh Sajad Jalili Habib 《Microsystem Technologies》2021,27(1):189-199
Microsystem Technologies - In this paper, a T-shape microchannel containing a mixing unit inserted in the straight main channel is designed to increase the mixing quality by geometrical changings... 相似文献
79.
80.
Mirjavadi Seyed Sajad Forsat Masoud Barati Mohammad Reza Abdella Galal M. Hamouda A. M. S. Afshari Behzad Mohasel Rabby Samira 《Microsystem Technologies》2019,25(9):3477-3488
Microsystem Technologies - Thermal post-buckling behavior of a geometrically imperfect/perfect piezo-magnetic nano-scale beams made of two-phase composites is analyzed in the present paper based on... 相似文献