The use of shading devices to reduce energy consumption can be considered one of the more common methods, its efficiency and impact on reducing carbon emissions have been less considered. the purpose of this study is to evaluate the energy consumption and efficiency of internal and external shading devices that are currently widely used in residential buildings and consequently their effect on reducing carbon emissions. To investigate this, a typical residential building in Gorgan was modeled. At the base of this, two types of interior shading of curtains and roller shades and two external shades overhangs and mat roller shades were examined. In this research, a model with 20 shading device modes was simulated. The modeling and the energy simulations were performed by Design-Builder (Version 6.1.6.005). According to the base-design geometry of the building appropriate shading options were proposed for the south façade and windows were double-glazed (DG). The output data showed that a white curtain with a medium-density openness factor of 3% has the highest efficiency in reducing energy consumption. However, purpose shading could save the annual energy consumption of the building by 4.3% compared to the base case, thus potentially saving up to 9.74 kg of CO2/m2 in the hottest months of the year and 2.45 kg of CO2/m2 annually. While most researchers are looking for sophisticated technologies, some simple methods such as the use of proper shadings can play a significant role in reducing carbon emissions and environmental sustainability. پرونده مقاله

Cities use a lot of energy sources and they form more than 70 percent of global carbon emissions. It is very important to measure the relationship between urban form and energy consumption. The form of different building blocks in the city can create different microclimates and subsequently affect the thermal comfort and energy performance of each building. Building blocks form includes different variables. The purpose of the research was to predict the effect of the layout pattern of building blocks on the thermal conditions of the building and the annual energy consumption of the building. The general pattern of building block layout (discrete, linear, centripetal) and its characteristics, including length, depth and direction, were considered as independent variables of the research and the annual energy consumption of the building as a dependent variable. The thermal conditions in the building are based on the PMV thermal index as a mediating variable. This research is a quantitative study that includes a literature review and research and software analysis. Accordingly, the samples of building block layouts based on typical patterns in the study area located in the CFA climate were simulated using DesignBuilder software and the results were compared with each other results. Energy consumption results have shown a direct relationship with the thermal conditions of the building. The layout patterns of the building block in the form of a medium-depth centripetal (annual energy consumption: 52718.5 wh/m2) and a short-length linear (annual energy consumption: 54127 wh/m2) can be considered as favorable options in terms of annual energy consumption. Also, changing the direction of building blocks with a linear form causes a significant change in energy consumption (It increases by 10.7% compared to the short linear pattern), and in the discrete pattern, considering designing strategy like insulation for external walls are important to prevent heat loss. پرونده مقاله

Using mineral admixtures in cement composites as a way to improve their mechanical and durability properties is a common practice in concrete technology. Among them silica fume and nano-silica effectively influence the composite's early and long-term properties. Due to the limited particle size distribution of nano and micro silica it is expected that the incorporation of some mineral additives with a size of greater than 500 nm may result in better mechanical and durability performance because of the filler effect. In this study, the effect of different percentages of TiO2 on mechanical properties of cement composites containing nano-silica and silica fume was investigated. Six designs were tested for compressive strength with respect to zero, 2.5 and 5 percent replacement of cement with TiO2. The addition of TiO2 has led to an increase in compressive strength. The best results from the sample with 2.5% TiO2 are obtained. This could be due to the effect of TiO2 particles filling. Comparison of SF3, SF2 and SF1 at 28 days of age showed that SF2 increased the compressive strength. This shows that TiO2 has a great potential for improving the mechanical properties of composite cement.The results showed that the addition of TiO2 had a positive effect on compressive strength. پرونده مقاله

Using mineral admixtures in cement composites as a way to improve their mechanical and durability properties is a common practice in concrete technology. Among them, silica fume and nano-silica effectively influence the composite's early and long-term properties. Due to the limited particle size distribution of nano and micro-silica, it is expected that the incorporation of some mineraladditives with a size greater than 500 nm may result in better mechanical and durability performance because of the filler effect. In this study, the effect of different percentages of TiO2 on the mechanical properties of cement composites containing nano-silica and silica fume was investigated. Six designs were tested for compressive strength with respect to zero, 2.5, and 5 percent replacementof cement with TiO2. The addition of TiO2 has led to an increase in compressive strength. The best results from the sample with 2.5% TiO2 are obtained. This could be due to the effect of TiO2 particles filling. Comparison of SF3, SF2, and SF1 at 28 days of age showed that SF2 increased the compressive strength. This shows that TiO2 has a great potential for improving the mechanical properties ofcomposite cement. The results showed that the addition of TiO2 had a positive effect on compressive strength. Increasing TiO2 nanoparticles content of more than 3 wt% is caused to reduce the compressive strength according to past studies. But in this study is shown that by adding 3% nanocillis or 20% silicified to increased TiO2 nanoparticles content of more than 3% wt, the results ofcompressive strength are not reduced. The use of 3% combined nano-silica or 20% silicafium will cover this defect of increased TiO2 nanoparticles content ofmore than 3% wt. پرونده مقاله

عدم تحرک بدنی یکی از عوامل خطر پیشرو، برای مرگ‌ومیر جهانی است که حدود 20 تا 30 درصد تخمین زده می‌شود. محیط نقش به سزایی در سلامت جسمانی انسان ایفا می‌کند؛ اما دانش در مورد ویژگی‌های محیطی ادراک‌شده توسط فرد، بر میزان سلامتی از بسیاری از جهات ناشناخته باقی‌مانده است. بر همین اساس این پژوهش ارﺗﺒﺎط ﺑﯿﻦ ﺑﺮﺧﯽ ﻣﺘﻐﯿﺮﻫﺎي ﻋﻮاﻣﻞ ﺳﻄﺢ ﻣﺤﻠﻪ ﺑﺎ ﺳﻼﻣﺖِ خود رتبه‌بندی شده (SRH) در بین مردم مازندران را موردبررسی ﻗﺮار می‌دهد، ارﺗﺒﺎط عوامل محیطی با میزان سلامت جسم را مقایسه و سپس نقش ترجیح محیط به‌عنوان متغیر واسطه‌ای بررسی می‌گردد. این تحقیق ازنظر هدف از نوع تحقیقات کاربردی و به لحاظ نحوه گردآوری اطلاعات، از نوع پیمایشی و توصیفی محسوب می‌شود. در گام نخست عوامل مؤثر بر ادراک محیط از منابع معتبر داخلی و خارجی استخراج گردید و سپس توسط پرسشنامه نظرات افراد ثبت شد. جامعه‌ی آماری توسط نمونه‌گیری طبقه‌بندی‌شده با تعداد نمونه‌ی 450 نفر در محلات برگزیده‌ی شهرهای نور، آمل، بابلسر و چالوس در استان مازندران انجام گردید. پرسش‌نامه در دو بخش و به‌طور هم‌زمان جمع‌آوری ﺷﺪ. در بخش اول ﺑﺮاي اندازه‌گیری ﺳﻼﻣﺖ جسمانی از پرسشنامه‌ی استاندارد سلامت خود رتبه‌بندی شده استفاده شد. سپس ﺑﺮاي ﺳﻨﺠﺶ ادراک ویژگی‌های ﻣﺤﻠﻪ و ترجیحات افراد نسبت به محیط ﻣﺤﻠﻪ، تأثیر مؤلفه‌های یکسان، شامل؛ امکانات، امنیت، مقصد و زیبایی‌شناسی موردسنجش قرار گرفت. داده‌های جمع‌آوری‌شده توسط، برازش مدل یابی معادلات ساختاری مورد تحلیل قرار گرفت. نتایج نشان داد که ادراک ویژگی‌های محیط با عدد 0.30 بر میزان سلامت جسم مؤثر است، همچنین ویژگی محیط نیز با عدد 0.15 بر ترجیح محیط اثر مثبت و معنادار داشت. عامل ترجیح محیط به‌عنوان متغیر واسطه‌ای با عدد 0.18- بر میزان سلامت نتیجه‌ی معکوس و معنادار داشت. به‌طوری‌که با کاهش ترجیحات محیط، شاهد افزایش سلامت جسم هستیم. پرونده مقاله

Using mineral admixtures in cement composites as a way to improve their mechanical and sustainable environmental properties is a common practice in concrete technology. Among them nano-silica effectively influences the composite's early and long-term properties. In this study, the effect of different percentages of TiO2 (0, 2.5 and 5 %) on self-cleaning properties and water absorption of cement composites containing nano-silica were investigated. according to the use of different cementitious material (nano-silica) and TiO2 in mix proportions, to obtain mixtures with a desirable workability, superplasticizer was added in different volume percentages.Better size distribution and pore refinement lead to a denser cement matrix with low porosity which in turn considerably lower the water absorption of the cement composites. the maximum final water absorption according to ASTM C497 is 9% for method A and 8.5% for method B. Comparsions of water absorption tests as a result of adding of TiO2 and nano-silica in concrete show that the maximum final water absorption is 4.9% in N1 design mixture and the minimum final water absorption is 4.3% in N2 design mixture.The incorporation of TiO2 has positively affected the results for nano-silica containing specimens. A decrease of 6.5% and 11.1% between N1 and N3 respectively shows the positive effect of TiO2 on decrease of water absorption. The results show that TiO2 along with nanosilica has great potential for improving the environmental and self- cleaning properties of concrete facades of buildings in cities exposed to high levels of cleanliness. پرونده مقاله