【摘要】 采用紫外-可见(UV-Vis)反射光谱对天然与改色处理的金色海水养殖珍珠进行了谱图对比性研究,并进一步探究了上述天然与经改色处理金珠中外层的珍珠层及内核中文石型碳酸钙的ν3,ν1,ν2和ν4特征吸收峰位的频率改变特征。结果表明:(1)基于金珠样品的UV-Vis反射谱图的测试,天然金珠样品由于表面微结构的差异,同一颗天然金珠的UV-Vis反射光谱存在一定的差异性。同时,依据改色处理金珠的UVVis反射谱图的吸收峰的峰位及其谱图特征,首次将目前较常见的改色处理金珠归纳为四类。(2)天然的或者经改色处理的金珠的外层珍珠层中的文石ν2振动频率相对内核中文石的ν2振动频率而言,前者出现明显的蓝移特征。但两者中文石的ν3,ν1,ν4振动频率则表现出一致性,且与合成文石的相关谱带频率一致。此外,天然与改色处理的金珠珍珠层中文石的红外特征吸收峰峰位一致,结果表明改色处理工艺对珍珠层中文石的晶体结构无直接影响。更多还原

【Abstract】 A comparative study on the natural-color golden seawater cultured pearls and the treated-color golden seawater cultured pearls were carried out by UV-Vis reflectance spectra.Furthermore,the frequency variations ofν3,ν1,ν2andν4bands of the aragonites(a crystal form of calcium carbonate)with the positions of nacreous layer and nucleus in natural or treated-color golden-color seawater cultured pearls were firstly systematically measured.The results showed that:(1)based on the results of UV-Vis reflectance spectra of natural or treated-color golden seawater cultured pearls,interestingly,it was firstly found that the natural-color golden one displays slight varied UV-Vis reflection spectra because of its different surface microstructure located on the outer nacreous layer.Meanwhile,according to the characteristic of UV-Vis reflectance spectra of treated-color golden ones, the treated-color ones were firstly classified to four categories.(2)The frequency ofν2band of aragonite in nacreous layer of natural-color or treated-color golden pearls was greater than the other one from theirs corresponding nucleus,namely A clear blue shift was observed in the former.But the other bands were not altered in the positions of nacreous layer and nucleus,and had the same valves with synthetic aragonites.Additionally,the location of absorption bands of aragonite in nacreous layer of natural or treated-color golden pearls had no frequency shift,which indicates that the behavior of color-treating had no effect on the crystal structure of golden pearls.更多还原