铷钟用特种玻璃管研究进展

铷钟是全球导航系统装备最早、数量最多的原子钟,被视为导航定位系统的"心脏".作为铷钟的关键基础材料,玻璃泡壳性能极大决定铷钟的计时精度和服役寿命.铷钟主要由光谱灯、滤光灯和吸收灯等构成,其中光谱灯泡由耐碱玻璃管灯焰制成,而滤光泡和吸收泡则由耐热玻璃加工而成.作者总结了铷钟用特种玻璃管的国内外研究进展,指出了国产玻璃管存在内在质量差、尺寸精度低、料性短和抗辐照能力弱等问题.最后,展望了铷钟用特种玻璃管的发展趋势.     

低介电玻璃的研究进展

新型电子、微电子和光电子元件的高功率化、高密度化、高集成化与高运行速度,需要新一代具有低介电性能的玻璃。表征了低介电玻璃的性能;根据玻璃组成的不同,分别介绍了石英玻璃、传统无机氧化物玻璃和微晶玻璃等低介电材料;最后展望了低介电玻璃发展趋势。     

特殊色散玻璃的研究进展

特殊色散玻璃,又称特殊相对部分色散玻璃,是偏离光学玻璃“正常线”较远的一类特种光学玻璃,具有特定的光学常数、高度透光性和较大的相对部分色散偏离值.本文介绍了特殊色散玻璃的研究进展,并指出了国内外差距.特殊色散玻璃是长焦距、大视场和高精度光学系统的关键优选材料,可应用于高品质光学系统中以消除二级光谱,简化和优化光学系统.最后展望了特殊色散玻璃的发展趋势.     

Effect of ~3B Group in Rings on Special Dispersion of B_2O_3-SiO_2-ZrO_2-Ta_2O_5-Na_2O System Glass

Borosilicate glasses,with x B_2O_3-(60-x)SiO_2-8ZrO_2-8Ta_2O_5-24Na_2O(7≤x≤59 mol%)composition,were fabricated by melt-quenching technique.NMR,UV-Vis,Raman and IR spectroscopic studies were utilized to investigate the structure of fabricated glasses.The NMR spectrum was deconvoluted into five Gaussian bands,assigned to ~4B(0B,4Si),~4B(1B,3Si),~4B(2B,2Si),~3B(rings)and ~3B(loose),to get their quantitative information.The relative dispersion deviation?P_(g,F) was attributed to the relative quantity of ~3B(rings)but not all ~3B groups,and B_2O_3 existed mainly as[BO_3]in rings firstly,and then as[BO_3]in loose condition.The UV-Vis spectra revealed that the quantity of non-bridging oxygen increased firstly and then decreased with increasing concentration of B_2O_3.Acting as complementary techniques,Raman and IR measurements revealed that four-coordinated boron and silica mainly existed as ~4B-O-B,and Si-O-Si in Q~2,respectively,as chain structure but not framework structure,and[B?_4]units prefered connections with borate rather than with silicate entities of the glass network in these studied glasses.In addition,the conclusion also certified that ~3B inloosecondition located in lower wavenumbers between 1 200-1 600 cm~(-1) in Raman spectra.