检索结果-南通市图书馆

Natural Radioactivity Measurements for Some Algerian building materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Physical Science and Application 2012年第6期2卷 171-174页

作者： Abdelfettah Belafrites Ahmed Tedjani Radiation Physics and Applieations Laboratory (RPAL) University of Jijel Jijel 18000 Algeria

The objective of this work is to assess the radiation hazards associated gamma rays from building materials. Natural gamma rays activities of natural radionuclide represented mainly by three natural radioactive series ^238U, ^235U and ^232Th, and the primordial ^40K in the samples of building materials which consist of bricks, ceramics, marble and gypsum from different areas of eastern Algeria are measured using gamma ray spectrometry. The values of the activities of these radionuclides do not clearly reflect the radiation hazard associated with these materials. Therefore, the radium equivalent （Raeq） concentration is defined taking into account the effectiveness of these isotopes in creating the radiation hazard. Radium equivalent activities, external and internal hazard indices （Hex and Hin） are calculated from the activities of ^226Ra, ^232Th and ^40K for suitability of the materials.

关键词： Natural radioactivity building materials y-ray spectrometry.

The Curriculum Reform Strategy of building materials in Higher Vocational Colleges Under the Background of"Three Educations"Reform

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Contemporary Educational Research 2022年第2期6卷 5-8页

作者： Jing Sun Chongqing Energy College Chongqing 402260China

With the deepening of the"three educations"reform,it has been emphasized that higher vocational colleges should strengthen the improvement of talent training strategies,improve the school-running quality,and explore from three aspects(teachers,teaching materials,and teaching methods)to improve the teaching efficiency and *** the teaching contents of building materials in higher vocational colleges as the research idea,this paper analyzes the current situation of the curriculum reform under the background of"three educations"reform and explores the corresponding reform strategies.

关键词： "Three educations"reform Higher vocational education building materials Curriculum reform Reform strategy

Numerical Modelling of Coupled Heat and Mass Transfer in Porous materials: Application to Cinder Block Bricks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2024年第9期14卷 2360-2373页

作者： Benjamin Kiema Ousmane Coulibaly Xavier Chesneau Belkacem Zeghmati Laboratory of Environmental Physics and Chemistry (LPCE) Department of Physics Joseph KI-ZERBO University Ouagadougou Burkina Faso Laboratory of Modelling Pluridisciplinary and simulation (LAMPS) University of Perpignan Via Domitia Perpignan France

In this work, we present numerical modelling of coupled heat and mass transfer within porous materials. Our study focuses on cinder block bricks generally used in building construction. The material is assumed to be placed in air. Moisture content and temperature have been chosen as the main transfer drivers and the equations governing these transfer drivers are based on the Luikov model. These equations are solved by an implicit finite difference scheme. A Fortran code associated with the Thomas algorithm was used to solve the equations. The results show that heat and mass transfer depend on the temperature of the air in contact with the material. As this air temperature rises, the temperature within the material increases, and more rapidly at the material surface. Also, thermal conductivity plays a very important role in the thermal conduction of building materials and influences heat and mass transfer in these materials. materials with higher thermal conductivity diffuse more heat.

关键词： Numerical Modelling Coupled Transfer building materials Luikov Model Finite Differences

Material Analysis of Traditional Folk Dwellings and Its Modern Inheritance:A Case Study of Traditional Folk Dwellings in Hunan Province

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Landscape Research 2024年第4期16卷 31-34页

作者： WEN Wen School of Architecture and Art North China University of TechnologyBeijing 100144China

Traditional folk dwellings contain rich cultural connotations and plain architectural *** architecture,material is the most fundamental thing,different materials can demonstrate different architectural forms,and reflect local characteristics and change of the ***,it is of great significance to explore the material selection of traditional Chinese folk *** paper took traditional folk dwellings in Hunan for example to analyze the regional materials and construction of these dwellings,discussed the application of traditional materials in modern architecture,used some cases to explore the innovative application of traditional materials,so as to figure out the new direction of applying traditional materials,and provide references for the construction of modern architecture.

关键词： Traditional folk dwellings building materials Hunan

Basic Characteristics of an Appropriate Waste Fillers for Solvent Free and Water-Borne Industrial Polymer Floors and Their Utilization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Civil Engineering and Architecture 2024年第3期18卷 141-147页

作者： Jana Kosikova Brno University of Technology Faculty of Civil EngineeringInstitute of Technology of Building Materials and ComponentsVeveří331/9560200 BrnoCzech Republic

Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its *** tendency to reduce of solvents and diluents contained in the materials appeared at the end of 90´*** situation was supported by the Council of Europe in 2004 to reduce VOC emissions to zero till *** materials were thus largely replaced by solvent free materials from which the volatile substances are not released into the *** pressure continued to increase,and over the past decade began to take centre stage water-based *** the Czech market solvent based material is still occasionally used,but predominant are solvent free *** are no commonly used materials containing wastes as fillers in new water-borne and solvent-free epoxy *** identification of the waste material as a potential filler is a set of properties that determine the limits of secondary raw materials or waste as a *** paper describes the basic characteristics which must be selected to meet the requirements,to affect negatively the workability,sedimentation,properties and behavior of the final floor *** materials must comply with special requirements,such as resistance to chemicals,*** part of paper talks about utilization of polymer floors and their mechanical properties.

关键词： Industrial polymer flooring materials waster fillers building materials

Development of a procedure for estimating the parameters of mechanistic VOC emission source models from chamber testing data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

building Simulation 2021年第2期14卷 269-282页

作者： Zhenlei Liu Andreas Nicolai Marc Abadie Menghao Qin John Grunewald Jianshun Zhang Department of Mechanical and Aerospace Engineering Syracuse UniversitySyracuseUSA Dresden University of Technology DresdenGermany University of La Rochelle La RochelleFrance Technical University of Denmark Kongens LyngbyDenmark School of Architecture and Urban Planning Nanjing UniversityNanjingChina

In order to evaluate the impacts of volatile organic compounds(VOCs)emissions from building materials on the indoor air quality beyond the standard chamber test conditions and test period,mechanistic emission source models have been developed in the ***,very limited data are available for the required model parameters including the initial concentration(C_(m0)),in-material diffusion coefficient(D_(m)),partition coefficient(Kma),and convective mass transfer coefficient(k_(m)).In this study,a procedure was developed for estimating the model parameters by using VOC emission data from standard small chamber *** the procedure,initial values of the model parameters were refined by multivariate regression analysis of the measured emission *** verify the procedure and estimate its uncertainty,simulated chamber test data were generated by adding 10% experimental uncertainties on the theoretical curve from the analytical solution to a mechanistic emission *** the procedure was applied to the generated data to estimate the model *** indicated that estimates converged to the original parameter values used for the data generation and the error of estimated parameters D_(m1)C_(m0) and K_(ma) were within±10%,±23%,and±25%of the true values,*** procedure was further demonstrated by applying it to estimate the model parameters from real chamber test *** application of the procedure would result in a database of mechanistic source model parameters for assessing the impact of VOC emissions on indoor pollution load,which are essential input data for evaluating the effectiveness of various indoor air quality(IAQ)design and control strategies as well as the energy required for meeting given IAQ requirements.

关键词： building materials volatile organic compounds(VOCs) emission source model indoor air quality building energy efficiency

Maximizing deviation method for multiple attribute decision making under q-rung orthopair fuzzy environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2020年第5期16卷 1073-1087页

作者： Jie Wang Gui-wu Wei Cun Wei Jiang Wu School of Business Sichuan Normal UniversityChengdu610101PR China School of Statistics Southwestern University of Finance and EconomicsChengdu611130PR China

Because of the uncertainty and subjectivity of decision makers in the complex decision-making environment,the evaluation information of alternatives given by decision makers is often fuzzy and *** a generalization of intuitionistic fuzzy set(IFSs)and Pythagoras fuzzy set(PFSs),q-rung orthopair fuzzy set(q-ROFS)is more suitable for expressing fuzzy and uncertain ***,in actual multiple attribute decision making(MADM)problems,the weights of DMs and attributes are always completely unknown or partly known,to date,the maximizing deviation method is a good tool to deal with such ***,combine the q-ROFS and conventional maximizing deviation method,we will study the maximizing deviation method under q-ROFSs and q-RIVOFSs in this ***,we briefly introduce the basic concept of q-rung orthopair fuzzy sets(q-ROFSs)and q-rung interval-valued orthopair fuzzy sets(q-RIVOFSs).Then,combine the maximizing deviation method with q-rung orthopair fuzzy information,we establish two new decision making *** this basis,the proposed models are applied to MADM problems with q-rung orthopair fuzzy *** with existing methods,the effectiveness and superiority of the new model are *** method can effectively solve the MADM problem whose decision information is represented by q-rung orthopair fuzzy numbers(q-ROFNs)and whose attributes are incomplete.

关键词： Multiple attribute decision making(MADM) q-rung orthopair fuzzy sets(q-ROFSs) q-rung interval-valued orthopair fuzzy sets (q-RIVOFSs) Maximizing deviation method building materials

Enhanced Thermal Performance of Roofing materials by Integrating Phase Change materials to Reduce Energy Consumption in buildings

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Renewable materials 2021年第3期9卷 495-506页

作者： Chanita Mano Atthakorn Thongtha Department of Physics Faculty of ScienceNaresuan UniversityPhitsanulok65000Thailand

This work focused on characterizing and improving the thermal behavior of metal sheet *** decrease the heat transfer from the roof into a building,we investigated the efficiency of four types of phase change materials,with different melting points:PCMІ,PCM II,PCM III and PCM IV,when used in conjunction with a sheet metal *** exterior metal roofing surface temperature was held constant at 50℃,60℃,70℃and 80℃,using a thermal source(halogen lights)for 360 min to investigate and compare the thermal performance of the metal sheet roofing with and without phase change materials for each *** thermal behaviors of the phase change materials were analyzed by differential scanning calorimeter(DSC).The results showed the melting points of PCMІ,PCM II,PCM III and PCM IV were around 45℃,50℃,55℃and 59℃,*** integration of PCM IV into the metal roofing sheet increased the thermal performance by reducing the room temperature up to 2.8%,1.4%,1.0%and 0.7%when compared with the normal metal roof sheet,at the controlled temperatures of 50℃,60℃,70℃and 80℃,*** thermal absorption of the phase change materials also caused a time delay in the model room reaching a steady *** integration of phase change materials with metal roofing sheets resulted in better thermal performance and conservation of electrical energy by reducing the demand for cooling.

关键词： Roof metal sheets phase change materials energy saving thermal storage building materials

Assessment of Indoor and Outdoor Radon Levels in South Lebanon

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2014年第3期5卷 214-226页

作者： Mohammed A.Kobeissi Omar El Samad Khaled Zahraman Ibrahim Rachidi Lebanese Atomic Energy Commission National Council for Scientific ResearchRiad ElsolhBeirutLebanon Department of Physics Faculty of Sciences(I)The Lebanese UniversityHadethBeirutLebanon

The presence of high indoor radon concentrations,Cx,is a major concern of the public *** of indoor radon in South Lebanon have been achieved using CR-39 *** ranged between 30 and 122 Bq m-3 in one of the major towns in the area and are compared with measured atmospheric air *** seasonal variation of Cxindoors has been observed,although 90%of the obtained indoor Cxmeasurements are below 100 Bq *** homes produced Cxreadings above the permissible *** showed that the ventilation effect played a major factor in reducing radon concentration levels *** assessment has been *** effective doses of radon varied from 1.01±0.10 to 8.65±0.50 m Sv a-1 in six homes in one of the four cases *** dosage values are above the permitted limit of 2.5 m Sv *** types of granite contained in the studied homes were identified and their contributions to radon levels indoors were calculated.

关键词： building materials CR-39 Effective dose Granite exhalation rate Lebanon Radon risk assessment