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1.
The conception of net zero energy buildings (NZEB) has been introduced to limit energy consumption and pollution emissions in buildings. Classification of NZEB is based on renewable energy (RE) supply options, energy measurement process, RE-sources location, and balances whether are energetic or exergetic. In general, it is traditionally agreed that there are three main steps to reach the NZEB performance, starting through the use of passive strategies, energy efficient technologies, and then RE generation systems. Then, these three steps could be accompanied with the smart integration of advanced efficient energy technologies. A state of the art shows that the main ZEB studies are related to: energy savings, reduce electric bills, energy independence, pollution reduction, and occupants comfort, in addition, others are more interested in the aesthetic aspect by combining modern technologies with innovations to achieve high energy and sustainability performance. Building optimization is a promising technique to evaluate NZEB design choices; it has been adopted to choose the perfect solution to reach the zero energy performance through the optimization of an objective function related to energy (thermal loads, RE generation, energy savings) and/or environment (CO2 emissions) and/or economy (life-cycle cost (LCC), net-present value (NPV), investment cost). This paper starts by presenting the global energetic and pollution challenges the world faces. Moreover, it shows, to the best to the author’s knowledge, the existing NZEB definitions and the corresponding case studies investigated in 8 different climatic zones (humid continental, humid subtropical, Mediterranean, moderate continental, moderate continental, marine west coast, tropical, semi-arid and hot), the paper also focus on the importance to treat each climate separately. Even in the same country, two or more climates may co-exist. NZEBs drawbacks are also presented. Furthermore, different optimization problems are reviewed in the last section. Building energy optimization methods are employed to obtain the ideal solution for specific objective functions which are either related to energy, and/or environment and/or economy. Optimization variables are distributed between passive and/or RE generation systems. Finally, a table summarizing the most commonly used electric and thermal RE applications which yield to the zero energy balance in each climate, as well as three flowcharts are presented to summarize the whole three-stage procedure, to reach NZEB, starting from building designing, passing through the optimization procedure, and lastly categorizing the zero energy balance. 相似文献
2.
Mokhtar Adel Boukoussa Bouhadjar Baba Ahmed Abderrazzak Abdelkrim Soumia Djelad Amal Hachemaoui Mohammed Zaoui Farouk Bengueddach Abdelkader Sassi Mohamed 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(7):2615-2633
Journal of Inorganic and Organometallic Polymers and Materials - The discharge of industrial waste comprising organic pollutants into aquatic environment induces numerous health risks. Crosslinked... 相似文献
3.
A simple method was developed for labeling N-{4-[(3-chloro-4-fluorophenyl)amino]quinazolin-6-yl}-3-bromopropionamide, an EGFR inhibitor, with radioactive iodine via nucleophilic iododebromination. The factors affecting the radiochemical yield of 125I-EGFR such as reaction medium, substrate concentration, CuCl concentration, and temperature were examined. Reducing agents such as ascorbic acid, SnCl2, and Na2S2O5 were used to prevent disproportionation. The radiochemical yield and purity of the labeled product were determined by TLC and HPLC. 相似文献
4.
Aerosol dispersion in living spaces especially bioaerosols, due to accidents or deliberate acts, is of significant current interest. Computational fluid dynamics (CFD) provides an accurate and detailed platform to study the influence of different parameters on aerosol distribution in indoor spaces. The simulations however are time consuming and site-specific. The work here introduces an approach toward addressing this challenge. During emergencies, an accurate, quicker, and more general model is required to give rapid answers to first responders. Significant parameters influencing aerosol behavior in an office room were identified and through dimensional analysis, nine dimensionless groups were developed. Fractional factorial design was used to build sixteen scenarios to explore the design space. These scenarios were then simulated using a comprehensive CFD model. Large eddy simulation with the Smagorinsky subgrid scale model was applied to compute the airflow. Aerosols were modeled as a dispersed solid phase using the Lagrangian treatment. The influence of the dimensionless groups on the temporal variation of the number of aerosols in the room and the spatial distribution of the particles in the room was analyzed. The results showed that all the identified dimensionless groups were significant. Multiple linear regression models were developed for the prediction of the number of aerosols in the room and their spatial distribution as a function of the significant parameters influencing aerosol transport. The linear models accurately predicted the data on which they were based but did not predict the results of the independent tests as well. The limited predictive ability of the model showed that the relationships between the dimensionless groups are nonlinear and a higher level of experimental design will have to be applied to better explore the design space. 相似文献
5.
Mohamed I.A. Othman Kh. Lotfy R.M. Farouk 《Engineering Analysis with Boundary Elements》2010,34(3):229-237
A general model of the equations of generalized thermo–microstretch for a homogeneous isotropic elastic half–space is given. The modulus of elasticity is taken as a linear function of reference temperature. The formulation is applied to generalized thermoelasticity theories, the Lord–?hulman and Green–Lindsay theories, as well as the classical dynamical coupled theory. The normal mode analysis is used to obtain the exact expressions for the displacement components, force stresses, temperature, couple stresses and microstress distribution. The variations of the considered variables through the horizontal distance are illustrated graphically. A comparison is made with the results predicted by the three theories in case of temperature–independent modulus of elasticity. 相似文献
6.
In this article, we report on the synthesis of cellulose esters by the reaction of cellulose and some cyclic anhydrides, such as succinic, maleic, and phthalic anhydrides. For this, an esterification method was finalized. Indeed, cellulose extracted from Posidonia biomass was first solubilized in the solvent system lithium chloride (LiCl)/N,N‐dimethylacetamide and then esterified by cyclic anhydride in the presence of catalysts such as N,N‐dimethyl‐4‐aminopyridine, tripropylamine, tributylamine, and calcium carbonate. This method was fast and reproducible with the LiCl system as a solvent and with an efficient activation by controlled microwave power. In this way, the reaction time was reduced from several hours to just a few minutes. The reaction products were characterized by IR and solid‐state cross‐polarization/magic angle spinning 13C‐NMR spectroscopy. The degree of substitution (DS) and the grafted ester group content of the different products were obtained by alkali saponification followed by titration of the excess alkali. Two activation methods were compared, and the results show that the application of classical heating gave less successful results than those obtained by microwave activation. Indeed, with microwave activation, a higher DS (2.25) was obtained after 10 min. However, with classical heating, a value of DS equal to 1.2 was obtained after 12 h. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
7.
The anodic behavior of gold has been investigated in presence of chloride and/or water in 1-butyl-3-methylimidazolium methanesulfonate (BMI CH3SO3) ionic liquid (IL). The cyclic voltammetry (CVs) in presence of chloride ions shows two waves attributed to the oxidation of the gold electrode which occurs under two steps: the first one is attributed to the electrochemical dissolution of gold into to gold(I), while the second one is attributed to an overlap of the chloride oxidation step as well as the oxidation of Au(I) to Au(III). Furthermore the determination of water and chloride content in IL allowed observing that the passive layer induced by water could be removed under chloride. Thanks to those results we were able to clarify the conditions of gold recovering in this kind of electrolyte. 相似文献
8.
Triphenylmethane dyes react at ambient conditions with chrysotile asbestos to form homogeneously coloured fibres. Formation of the chelates on the fibre varies: for Basic Fuchsin, Malachite Green and Methyl Blue equilibrium is reached in 1 h, the concentration on the fibre is 1% to 2.4%, and increases slightly on boiling. For Brilliant Blue R, Crystal Violet, and Methyl Violet equilibrium is reached after 16 to 24 h, the concentration on the fibre is 8% to 10%, and increases greatly on boiling reaching 10% to 31%. No precipitates were observed on the coloured fibre under the scanning electron microscope indicating a chelate formation. This was also supported by X-ray diffraction and infrared analysis. 相似文献
9.
The annealing effects on the structural and electrical properties of fluorinated amorphous carbon (a-C:F) thin films prepared from C6F6 and Ar plasma are investigated in a N2 environment at 200 mTorr. The a-C:F films deposited at room temperature are thermally stable up to 250 °C, but as the annealing temperature is increased beyond 300 °C, the fluorine incorporation in the film is reduced, and the degree of crosslinking and graphitization in the film appears to be enhanced. At the annealing temperature of 250 °C, the chemical bond structures of the film are unchanged noticeably, but the interface trapped charges between the film and the silicon substrate are reduced significantly. The increased annealing temperature contributes the decrease of both the interface charges and the effective charge density in the a-C:F film. Higher self-bias voltage is shown to reduce the charge density in the film. 相似文献
10.
Nawal Makhloufi Nadia Chougui Farouk Rezgui Elias Benramdane Carmen S. R. Freire Carla Vilela Armando J. D. Silvestre 《应用聚合物科学杂志》2021,138(20):50450
The present study investigated the fabrication and characterization of bio-based sustainable films composed of a terrestrial plant raw material, namely Opuntia ficus-indica (OFI) cladodes powder (CP) and a marine seaweed derivative, namely agar (A). The effect of glycerol concentration on the properties of the casted films was evaluated at four different contents, namely 30, 40, 50 and 60 wt%. The films present UV-blocking properties, as well as moderate mechanical performance, thermal stability, and water vapor transmission rate (WVTR). The results point to an increase in thickness, elongation at break, moisture content, water solubility, and WVTR with increasing glycerol content. On the contrary, Young's modulus, tensile strength, and water contact angle decreased as glycerol concentration increased. The best combination is obtained for the film with 30% glycerol, based on an intermediate compromise between physical, mechanical, thermal, and barrier properties. All these outcomes express the potentiality of the powder obtained from grinding the OFI cladodes as raw material to produce low-cost films for the development of sustainable packaging materials. 相似文献