جستجوی مقالات مرتبط با کلیدواژه « Limonite » در نشریات گروه « فنی و مهندسی »

The Use Of Color Spectrums In The Urban Space Can Be Seen In The Facades Of Buildings, Flooring, Urban Furniture, Sidewalks And Streets. The Use Of Colored Concrete For Facade Construction And Decoration Design Can Be Welcomed For Many Reasons. Also, This Method Does Not Require The Use Of Other Materials To Cover The Work, In Which Case The Costs Of Facade Work Will Be Significantly Reduced. But Temperature Changes And The Cycle Of Melting And Freezing In Unstable Environmental Conditions Is One Of The Factors Of Concrete Failure. Therefore, In Addition To Beauty, Colored Concrete Must Be Resistant To Different Environmental And Atmospheric Conditions. Yellow Is One Of The Three Main Colors In The Color Wheel. In Architecture, Yellow Is A Practical Color And It Makes Spaces Appear Bright And Large Due To The Large Amount Of Light It Reflects. The Pigment Of Mung Bean Or Limonite Is A Type Of Mineral Soil That Has A Large Amount Of Iron Oxide. This Pigment Is Found In Dull Yellow Or Mustard Colors. In This Research, To Change The Color Of Concrete To Yellow, White Cement And Limonite Pigment Were Used In Different Weight Ratios Of 5%, 10%, 15% And 20% In Concrete. Further, To Check The Behavior And Durability Of Concrete, Compressive Strength Tests, Water Absorption In Hardened Concrete, And Durability Of Melting And Freezing Were Investigated. The Results Of This Research Showed That The Colorability Of 5% And 10% Limonite In Concrete Will Cause Pea And Cream Color And The Use Of 15% And 20% Will Cause Yellow Color. Also, The Use Of 10% Limonite In Concrete Increased The 28-Day Compressive Strength By 8%. But Due To The High Water Absorption Of Limonite, Its Freezing Durability Decreased Compared To The Control Sample.

In this research different samples of Iron Ore in Shams Abad Iron mine have been investigated. The samples included different compositions of iron ore that the most of them are hematite¡limonite¡ siderite and goethite. The samples were taken from depth parts of the mine and after Preparation and expiration equilibrium time¡ the specific activity of natural radionuclides were determined using gamma ray spectrometry method with employing high purity germanium detector (HPGe) with 30% relative efficiency. The activity concentration of 226Ra¡ 232Th and 4 K in thesesamples varied from 9.39±0.53 to 271.70±1.84¡