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Abstrak :
Human teeth enamel have been irradiated with gamma radiation from Co60 at room temperature and at liquid nitrogen temperature. Paramagnetic centers are formed and have been detected by using electron spin resonance (ESR) spectrometer at room temperature. The main signal is very stable asymmetric singlet, and attributed to h centers in the hydroxyapatite crystals. It is revealed that several factors influence the amplitude of the asymmetric signal. The amplitude and pattern of the asymmetric signal which depend on the orientation of the sample with respect to the magnetic field are analyzed. Based on the properties of the asymmetric signal the difference between the microcrystal arrangement of healthy and diseased teeth are explained.

Abstrak :
ABSTRAK
Sampel kutikula dibuat dari udang galah yang dipelihara dalam akuarium, dengan umur bervariasi dari saat setelah molting sampai dengan molting berikutnya.

Spektra infra merah kutikula yang dipanaskan dengan suhu 600°C dan 900°C selama 6 jam, dan diukur dengan jangkauan frekuensi 4000 - 400 em-x, memberikan informasi bahwa pertumbuhan kristal apatit berlangsung dalam 2 tahap. Mula-mula kristal apatit tumbuh cepat, dalam waktu pendek, kemudian diikuti oleh pertumbuhan yang lebih lambat dalam waktu yang lebih lama, sampai akhirnya berhenti.

Hasil difraksi sinar X memperkuat hasil spektrometer infra merah. Diperoleh pula informasi bahwa kandungan kalsium fosfat dalam kutikula didominasi oleh ACP, termasuk dalam kutikula moltinng.

Spektrometer RSE (Resonansi Spin Elektron) digunakan khusus untuk mengamati apatit karbonat. Pertumbuhan apatit karbonat dalam kutikula sejalan dengan pertumbuhan kristal apatit. Meskipun kutikula mengandung banyak ACP, apatit karbonat, khususnya tipe A ikut dicerna dan dikeluarkan dari kutikula pada saat persiapan molting.

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ABSTRACT
The samples of giant prawns cuticle were made with the prawn age variations during one molting cycle.

Infrared spectra of the cuticle after heating with temperature 600°C and 900°C for 6 hours, and measured with the frequency range of 4000 - 400 cm-l, showed that the growth of crystals proceeded into two steps. In the first period, the crystals were produced with high rate, within a few days C4-5 days], then followed by lower rate production for longer period, and finally it stopped.

The X-ray diffraction investigation supported the results of infrared spectroscopy. The X-ray diffraction patterns also informed that the calcium phosphate in the cuticle was dominated by ACP, including in the molting cuticle.

The carbonate apatite was studied by using Electron Spin Resonance spectrometer. The growth of the carbonate apatite crystals followed the same way as the crystals growth. Although the cuticle contains high amount of ACP, however, the carbonate apatite especially type A, was also digested and some of them was reabsorbed out of the cuticle during the molting preparation.

Abstrak :
ABSTRAK
Proses fisis klasifikasi kutikula udang galah dan udang windu diselidiki dengan menggunakan spectrometer infra merah., difraksi sinar X, dan resonansi spin elektron. Sampel kutikula dibuat dari udang dengan umur yang bervariasi, selama satu siklus molting.

Spektra infra merah dan profit difraksi sinar X digunakan untuk mengenali kehadiran kalsium karbonat dan kalsium fosfat Dalam kutikula terdapat kalsium karbonat dalam bentuk kalsit, dan kalsium fosfat dalam face ACP (amorphous calcium phosphate ), OCP (octacalcium phosphate ), dan apatit Pemanasan sampel dengan suhu 600"C dan 900°C dilakukan untuk mendeteksi OCP secara tidak langsung.

Ada dua cara klasifikasi. Metoda pertama mengakibatkan kW :Dada grup I mengandung apatit lebih tinggi dibanding dengan kutikula grup II yang klasifikasinya berlangsung dengan metoda kedua. Pada periode segera setelah molting, disamping material amorf, juga dibentuk material kristalin. Umumnya laju pertumbuhan apatit dalam kutikula udang galah lebih lambat dibanding dengan dalam kutikula udang windu.

Dalam kutikula udang galah, kalsit dan ACP tumbuh dominan, dan apatit tumbuh dengan ukuran kecil Kutikula molting selalu berisi apatit lebih rendah dibanding dengan kutikula non molting Berbeda dengan kutikula udang galah, apatit tumbuh lebih dominan dibanding dengan kalsit dalam kutikula udang windu. Kandungan ACP tinggi dalam kutikula non molting, tetapi tidak demikian dalam bra-Lila molting. Kutikula molting selalu berisi apatit lebih banyak dengan ukuran lebih tinggi dibanding dengan kutikula non molting.

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ABSTRACT
Physical calcification process of giant and tiger prawn cuticle were investigated by using infrared, X ray diffraction, and electron spin resonance spectroscopy. Samples were prepared from cuticle of the prawns with age variation within one moulting cycle.

Infrared spectra and X my diffraction profiles were used to identify the presence of calcium carbonate and calcium phosphate . The cuticle contains calcium carbonate in the form of calcite, and calcium phosphates in the form of ACP (amorphous calcium phosphate ), 0CP (octacalcium phosphate), and apatites. Undirect identification of OCP was performed by heating the samples at temperature 500°C and 900°C. Electron spin resonance (ESR) spectroscopy was used especially for detecting carbonates in calcites and apatites.

There are two methods of calcification. The first method classify the group I cuticles with higher amount of apatites compare with the second method in the group II cuticles. In the period just after moulting, the crystalline materials are formed besides the amorphous materials in the two groups of cuticles.In general the rate of apatite growth in the giant prawn cuticle is lower than in the tiger prawn cuticle.

In the giant prawn cuticle, calcites and ACP exist dominantly, and apatites form in small size. The moulting cuticle always contains less of apatites than the non moulting cuticle. Differently happened in the tiger prawn cuticle, apatites dominate more than calcites. The amount of ACP is high in the non moulting cuticle, but not in the moulting cuticle. The moulting cuticle always contains much more apatites and in bigger size than in the non moulting cuticle.

Abstrak :
Sampel senyawa kalsium fosfat dibuat dari larutan ion kalsium dan ion fosfat jenuh. Eksperimen dilakukan dengan perlakuan suhu 25 °C dan 70 °C, yang dikombinasikan dengan perlakuan pH 5, 7, 9 dan 11. Hasil presipitasi larutan pada suhu 70 °C mempunyai massa relatif lebih tinggi dibanding dengan massa presipitan yang dihasilkan oleh larutan pada suhu 25 °C. Pada umumnya massa presipitan meningkat dengan kenaikan pH. Analisis sampel dilakukan dengan spektrokopi inframerah, terutama pada sampel hasil presipitasi pada suhu 70 °C. Berdasarkan derajat belah pita absorpsi fosfat 􀁮4, dapat diketahui bahwa pada umumnya semua sampel mengandung kristal apatit dan yang meningkat dengan kenaikan pH larutan. Dari pemanasan sampel hasil presipitasi larutan dengan pH 11 diperoleh pula informasi bahwa molekul air, dapat berada pada permukaan kristal maupun terperangkap dalam struktur kristal.

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Infrared Spectroscopy of Precipitated Calcium Phosphate Compound. Samples of calcium phosphate compounds were produced from saturated solutions containing of calcium and phosphate ions. The experiments were carried out using solutions at temperature 25 °C and 70 °C, combined with different pH value of 5, 7, 9 and 11. Precipitation mass from solutions at 70 °C was relatively higher compare to that produced from solutions at 25 °C. It was also shown that generally the mass precipitation rose with the increasing of pH. Sample analyses were performed with the use of infrared spectroscopy, particularly for the samples produced from solutions at 70 °C. Based on the 􀁮4 phosphate absorption band, it was indicated that apatite crystals found in most samples which its amount gave rise to the increasing of pH. Infrared spectroscopy of the heated samples produced with pH 11 showed that water molecules could be present either at the surface of crystals or trapped in the crystal structure.