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Abstrak :
This handbook gives a comprehensive overview about Raman spectroscopy for the characterization of nanomaterials. Modern applications and state-of-the-art techniques are covered and make this volume essential reading for research scientists in academia and industry.

Abstrak :
Raman imaging has long been used to probe the chemical nature of a sample, providing information on molecular orientation, symmetry and structure with sub-micron spatial resolution. Recent technical developments have pushed the limits of micro-Raman microscopy, enabling the acquisition of Raman spectra with unprecedented speed, and opening a pathway to fast chemical imaging for many applications from material science and semiconductors to pharmaceutical drug development and cell biology, and even art and forensic science. The promise of tip-enhanced raman spectroscopy (TERS) and near-field techniques is pushing the envelope even further by breaking the limit of diffraction and enabling nano-Raman microscopy.

Abstrak :
ABSTRACT
This study aims to reveal the effects of pressure during cold isostatic pressing (CIP) on the microstructure and optical properties of fluorescent HAp complexes using Raman spectroscopy. Although the microstructure-dependent properties of fluorescent HAp complexes have been reported to improve the antibacterial properties of photocatalyst coating layers, the mechanism behind the changes in the fluorescence properties of highly compressed HAp complex has not yet been unveiled. CIP was successfully used to fabricate fluorescent HAp/amino acid complex, and their fluorescence intensities increased with increasing fabrication pressure. The concentration of amino acid increased proportionally with pressure, which suggests changes in the packing structures of the ligands in the HAp/amino acid complex. Polarized Raman spectroscopy measurements clearly detected ligands normally arranged to the HAp layer under high pressure fabrication conditions, which can provide the tightly packed ligand structure in the HAp/amino acid complex. These tightly packed ligand structure in the HAp/amino acid complex could emit stronger fluorescence owing to the increased density of complexations. This newly found pressure dependency in the optical properties of HAp/amino acid complexes is beneficial for developing biocompatible fluorescence materials or enhancement agents for antibacterial coating layers HAp / coating densification that lead to activate intermolecular interactions and subsequently intensify fluorescence.

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ABSTRACT
Penelitian ini bertujuan untuk mengungkap efek tekanan selama proses penekanan isostatik dingin pada struktur mikro dan sifat optik fluoresen kompleks HAp dengan menggunakan spektroskopi Raman. Meskipun sifat mikro ketergantungan dari fluoresen kompleks HAp telah dilaporkan yaitu untuk meningkatkan sifat antibakteri lapisan fotokatalis, mekanisme dibalik perubahan sifat fluorosensi dari kompleks HAp yang dilakukan kompresi belum terjawab. CIP berhasil digunakan untuk membuat fluoresen kompleks HAp/asam amino, dan intensitas fluoresensi mereka meningkat dengan meningkatnya penekanan saat fabrikasi. Konsentrasi asam amino meningkat secara proporsional dengan tekanan, yang menunjukkan perubahan dalam struktur pengepakan ligan pada kompleks HAp/asam amino. Pengukuran spektroskopi Raman dengan polarisasi dapat mendeteksi ligan dengan jelas yang biasanya diatur ke lapisan HAp dibawah kondisi fabrikasi tekanan tinggi, yang dapat memberikan struktur ligan yang padat dalam kompleks HAp.asam amino. Struktur ligan yang padat ini dalam kompleks HAp.asam amino dapat memancarkan fluoresensi yang lebih kuat karena meningkatnya kerapatan kompleksasi. Ketergantungan tekanan yang baru ditemukan ini dalam sifat optik kompleks HAp/asam amino bermanfaat untuk mengembangkan bahan fluoresensi biokompatibel atau agen peningkatan lapisan antibakteri.