Pengukuran Kristalinitas Silika berdasarkan Metode Difraktrometer Sinar-X
Keywords:
kristalinitas, kristobalit, kuarsa, opal, preparasi sampel, silica, tridimit, XRD, cristobalite, crystallinity, quartz, sample preparations, tridymite,Abstract
Sari. Mineralogi dan derajat kristalinitas mineral silika non- dan mikrokristalin dapat ditentukan dengan metode difraktometer sinar-X, yaitu dengan mengukur lebar peak atau hump pada setengah intensitas-maksimum difraksi pada posisi sekitar 4 . Hasil optimum pengukuran kristalinitas diperoleh bila sampel silika kering berukuran butir 75 hingga 106 μm dipreparasi pada cetakan aluminium dan dianalis mulai 10 hingga 402θ dengan kecepatan goniometer 0,62θ/menit dan interval pencatatan 0,01. Prosedur seperti ini akan mempunyai kesalahan tidak lebih dari 0,32θ.
Measurement of Silica Crystallinity Using X-Ray Diffraction Method
Abstract. Mirralogy and the degree of crystallinity of non- and microcrystalline silica could be determined using the X-ray diffraction method, i.e. by measuring the half-width peak or hump at about 4 . The optimum and most reproducible results were obtained when dry silica sample powder having a grain size of 75 to 106 μm was prepared at the aluminium holder and scanned from 10 to 402θ using goniometer speed of 0.62θ and a step size of 0.01. This procedure will give an experimental error less than 0.32θ.
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