ASSESSMENT OF NATURAL RADIOACTIVITY IN CONCRETE BLOCK, EXTRUDED CLAY BRICK, AND MUD BRICK TAKEN FROM OGBOMOSO, SOUTHWESTERN, NIGERIA

Yıl 2012, Cilt: 13 Sayı: 1, 23 - 29, 24.08.2012

Bolaji Ayınmode Rebecca Famakınwa Jonathan Ajayı

Öz

This study evaluates the natural radioactivity in concrete block, extruded clay brick, and mud brick taken from Ogbomoso city. The six samples were collected from different part of the city, and were analyzed using highly sensitive HPGe gamma spectrometer. The mean activity concentration in Bq Kg -1 of ⁴⁰K , ²³⁸ U (²²⁶Ra) and ²³²Th were 135.10 ± 3.23, 9.58 ± 3.16 and 14.30 ± 3.32 respectively in concrete block ; 66.34 ± 6.66, 6.81 ± 2.26 and 6.78 ± 2.58 respectively in mud brick; and 69.21 ± 6.88, 7.26 ± 2.54 and 3.51 ± 1.54 respectively in extruded clay brick. Also calculated were the radium equivalent activities, the hazard indexes, the absorbed dose rates and the effective dose rate. The extruded clay brick has the lowest value in all calculated parameters. The absorbed dose rate due to ²³⁸ U (²²⁶Ra), ²³²Th and ⁴⁰K at 1.0 m above the ground level in clay brick was 8.41 nGy h ^-1, annual effective dose was 0.04 mSv yr^-1 and also the internal and external hazard index was 0.07 and 0.02 respectively. All the measured parameters in all the samples were lower than the international criterion values, and therefore posses no radiological hazards.

Anahtar Kelimeler

Radioactivity, Bricks, Dose, Radium, Thorium

OGBOMOSO, GÜNEYBATI, NİJERYA’DAN ALINAN, BETON BLOK, BOYALI KIL TUĞLA VE KERPİÇ İÇİNDE DOĞAL RADYOAKTİVİTE DEĞERLENDİRİLMESİ

Öz

Bu çalışmada, Ogbomoso, Güneybatı, Nijerya’dan alınan, beton blok, boyalı kil tuğla ve kerpiç içinde doğal radyoaktivite değerlendirilmiştir. Altı örnek, Şehrin farklı kısımlarından altı örnek toplanmışvesonderecehassas HPGe Gama spektrometresi kullanılarak analiz edilmiştir. 40K , 238 U (226Ra) ve 232Th Bq Kg -1 için ortalama aktivite konsantrasyonu, sırasıyla beton blok içinde; 135.10 ± 3.23, 9.58 ± 3.16 ve 14.30 ± 3.32, kerpiç içinde; 66.34 ± 6,66, 6.81 ± 2.26 ve 6,78 ± 2,58, ve boyalı kil tuğla içinde; 69.21 ± 6.88, 7.26 ± 2.54 ve 3.51 ± 1,54 olarak ölçülmüştür. Ayrıca, radyum eşdeğer faaliyetleri, tehlike indeksler, absorbe edilen doz oranları ve etkin doz oranları hesaplanmıştır. Boyalı kil tuğla, tüm hesaplanan parametreleri için en düşük değerlere sahiptir. Absorbe edilen doz oranları 238 U (226Ra), 232Th veetkin doz 0.04 mSv yr-1 ve sırasıyla iç ve dış tehlike indeksler 0,07 ve 0,02 dir. Bütün örneklerdeki ölçülen tüm parametreler, uluslararası ölçüt değerlerinden düşüktür ve bu nedenle hiçbir radyolojik tehlikeye sahip bir parça yoktur. K için, kil tuğla zemin seviyesinden 1.0 m üzerinde, 8.41 nGy h -1 ve yıllık

Anahtar Kelimeler

Radyoaktivite, Tuğla, Doz, Radium, Thorium

Kaynakça

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