Statistical Study of Thermal Shock Damage of a Borosilicate Glass

The statistical aspects of thermal shock damage were addressed by examining the strength distributions of quenched specimens. It was observed that slow crack growth effects were minor, and that severe damage commenced near K _Ic. The increased range of retained strengths observed after thermal shock occurs because the low-strength portion of the distribution experiences the initial thermal shock damage. Crack arrest in the damaged specimens, examined by an energy balance, indicated that a large number of surface flaws actively extend during the initial stages of thermal shock damage.     

硼硅酸盐泡沫玻璃研究

以C和Sb2O3组合作为发泡剂,通过粉末烧结发泡工艺制备了硼硅酸盐泡沫玻璃,采用SEM观察了试样的微观结构形貌,并研究了试样的耐酸腐蚀性能.结果表明:当发泡剂C的质量分数为0.9%、Sb2O3的质量分数为8.1%时,在1200 ℃、保温30 min条件下,可以制备出平均孔径为0.2～1.0 mm、气孔分布较均匀的硼硅酸盐泡沫玻璃.试样中气孔结构主要与气泡内的气体压力、玻璃的表面张力和粘度有关.将试样浸泡在0.1 mol/L的稀硫酸中做耐酸腐蚀性实验,60 d内试样的质量先有微量增加后保持不变,这主要是由于稀硫酸进入试样的气孔结构中后形成了一层保护膜,从而阻碍了进一步的侵蚀.     

硼硅酸盐玻璃与钠钙硅玻璃浮法成型的对比研究

总结了浮法成型工艺的特点,介绍了浮法工艺对普通钠钙硅玻璃的要求,在此基础上提出从玻璃的熔化和成型温度要求,粘度-温度曲线要求,析晶温度上限要求等几个方面探讨耐热高强硼硅酸盐平板玻璃浮法成型的要求.     

无机抗菌硼酸盐玻璃材料的研究

采用高温熔融法，在硼酸盐玻璃的配合料中引入抗菌剂磷酸银，一次烧制而成制得抗菌玻璃材料，并对硼酸盐玻璃的抗菌性能和缓释性能进行了分析。结果表明：制备抗菌硼酸盐玻璃时，合适的银含量为1．5％-2．0％，处理温度在1100～1400℃即获得良好的抗菌效果和缓释性。     

Rb和Cs的提取研究

研究Rb、Cs在制盐过程中的走向,指出可从含Rb、Cs的低浓度原料中采用萃取工艺进行提取,方法简单可行。     

硼硅酸盐玻璃对耐火材料的侵蚀研究

主要针对熔制硼硅酸盐玻璃时对锆刚玉砖、镁砖、硅砖的侵蚀情况进行实验分析.为合理选择熔窑耐火材料提供参考.     

Vanadium in Borosilicate Glass

Understanding the role of V₂O₅ within borosilicate glass matrices is important for the development of novel matrices toward immobilization of sulfate containing high‐level nuclear wastes. Present investigation shows, within sodium barium borosilicate glass matrix V₂O₅ can be homogeneously added up to 5 mol% and beyond which it separates out into three phases, for example, (i) silica (ii) Barium (Ba) – Vanadium (V) oxide, and (iii) glass matrix. ²⁹Si MAS NMR (Nuclear Magnetic Resonance) studies of the samples show that below 5 mol% V₂O₅ addition, silicate network is dominantly constituted of Q² and Q³ structural units, whereas above this, the network gets more polymerized through formation of Q³ and Q⁴ units. In case of borate network, ¹¹B MAS NMR investigations revealed that the concentration of BO₄ [(0B, 4Si)] unit increases gradually up to 5 mol% and then it decreases at the cost of BO₄ [(1B, 3Si)], BO₃ (symmetric) and BO₃ (asymmetric) units. Micro‐Raman analyses of the samples showed that with additions of V₂O₅ in diluted concentrations, amorphous silicate network remained unaltered, whereas some amplification in signals corresponding to ring‐type metaborate and VO₅ units exists. It is therefore apparent from both MAS‐NMR and micro‐Raman studies that with V₂O₅ additions within the solubility limit (≤5 mol%), borate network gets depolymerized leading to decrease in hardness from an average value of 5.0–4.2 GPa.     

硼硅酸盐玻璃成分对硫酸钡热稳定性的影响

研究了硼硅酸盐玻璃主要成分(SiO₂、Na₂O、B₂O₃)对硫酸钡(BaSO₄)热稳定性的影响,分析BaSO₄分别与SiO₂、Na₂O、B₂O₃的混合物在不同温度(800～1 200℃)煅烧后的物相组成、显微结构、硫含量和拉曼光谱。结果表明:当BaSO₄:SiO₂摩尔比为7.5:92.5 (样品A)时,在温度低于1 200℃煅烧后其物相均为BaSO₄和SiO₂,温度达到1 200℃时出现了少量硅钡石(BaSi₂O₅)相;当BaSO₄:SiO₂:Na₂O为7:86:7 (样品B)时,在800℃煅烧后即出现了少量BaSi₂O₅相,当温度...     

硼硅玻璃管道的应用

介绍硼硅玻璃管道的性能、特点和应用情况;阐述其安装方法及其注意事项。     

水热法制得硼硅酸盐含水玻璃导电性的研究

以硼硅酸盐玻璃为原料 ,采用水热热压 (HHP)工艺制备了具有高电导性的含水玻璃 ,制得玻璃的电导率在 2 5℃时达 1.7× 10 -4 S.cm-1,在 15 0℃时达 1.2×10 -2 S .cm-1,已达到日本超导电玻璃电导率的数量级。并用IR、XRD、LCR等手段分析了玻璃的水化产物、水化过程中的物相和水化机理。同时研究了所制得含水玻璃固化体的导电机理及水化温度对固化体导电性影响。结果表明水在固化体中以分子水和结晶水为存在形式 ,≡SiOLi+H2 O ≡SiOH +Li+ +OH-,H2 O +≡Si-O -Si≡ ≡SiOH +≡SiO-,OH-+≡Si-O -Si≡ SiOH +≡SiO-为其水化机理反应式。该含水玻璃以离子导电为主 ,并且增大 -OH浓度或升高水化温度都有利于提高含水玻璃导电性     

Actinide Valences in Borosilicate Glass

Optical and Mössbauer spectra show that actinide ions are incorporated in a borosilicate glass matrix as U(VI), Np(IV), P(IV), and Am(III). Uranium was reduced by graphite to U(V) and U(IV), but Pu(IV) remained unchanged. It is inferred from their valences that Np, Pu, and Am are part of the borosilicate network and U is probably a network-modifier.     

混合碱土金属氧化物对硼硅酸盐玻璃热膨胀系数的影响

研究了4种碱土金属氧化物(MgO、CaO、SrO、BaO)替代Na2O后对硼硅酸盐玻璃热膨胀系数和软化温度的影响,对比分析了二元和三元混合碱土对玻璃热膨胀性能的影响,通过阿本法计算了玻璃的热膨胀系数并与实测值进行了比较。研究结果表明:碱金属与碱土金属氧化物形成的"混合碱-碱土效应"使得玻璃的膨胀软化温度显著提高;三元混合碱土的性能比二元混合碱土的性能好;通过阿本法计算的热膨胀系数值,含有2种碱土的玻璃的计算值小于实测值,而含有3种碱土的玻璃的计算值明显大于实测值。     

水热热压条件下玻璃水化过程的研究

本研究以硼硅酸盐系统的玻璃作为基础玻璃,考察基础玻璃粉末在水热热压条件下的反应过程,制备出一种水化玻璃固化体。利用IR,DTA,TG和DTG等分析方法讨论了水在水化玻璃固化体的存在形式,得出水在水化玻璃固化体是以硅烷醇基＝Si-OH和分子水两种形式存在的结论。并根据对水化过程中固化体的收缩量以及硅烷醇基＝Si-OH含量的分析,探讨了水化反应的基本机理,揭示出水热热压条件下玻璃的水化过程是由两个阶段的构成的;第1阶段主要是以离子交换为主的释碱过程,第2阶段是以水分子的扩散以及碱蚀为主的破坏玻璃网络的溶蚀过程。     

高硼硅酸盐玻璃的技术管理

根据高硼硅酸盐玻璃的特性,阐述了高硼硅酸盐玻璃在生产实践的全过程中,影响玻璃产品质量的原料选用、配合料制备工艺、熔制工艺等环节的各种因素,控制要求和采取的各种调整方法等一系列技术管理措施.     

Chemical Durability of Lanthanum-Enriched Borosilicate Glass

The role of lanthanum in the alteration kinetics at different degrees of reaction progress was investigated at 90°C and pH 7 by complementary chemical (SIMS), morphological (SAXS), and structural (NMR, Raman, and EXAFS spectroscopy) approaches. In the first step of alteration, the forward dissolution rate diminishes with the addition of lanthanum, resembling to the behavior previously observed for zirconium. Over longer alteration time, the glasses with the highest lanthanum concentrations reach silicon saturation more slowly, but unlike zirconium, do not result in larger quantities of altered glass. Lanthanum is entirely retained in the alteration layer and is uniformly distributed; it undergoes hydrolysis and recondensation mechanisms, and its coordination number increases from 6 to 9 during leaching. Reconstruction of the alteration layer occurred more slowly at higher REE concentrations, with a slowdown in repolymerization of the silicate network and structuring of its porosity.     

Structure of Rhenium-Containing Sodium Borosilicate Glass

A series of sodium borosilicate glasses were synthesized with KReO₄ or Re₂O₇, to 10,000 ppm (1 mass%) target Re, to assess effects of large concentrations of rhenium on glass structure and fto estimate solubility of ⁹⁹Tc, a radioactive component in low active waste nuclear glasses. Rhenium was used as a surrogate for ⁹⁹Tc for laboratory testing, due to similarities in chemistry, ionic size, and redox. Magic angle spinning nuclear magnetic resonance, Fourier transform infrared spectroscopy, and Raman spectroscopy were performed to characterize the glasses. Si was coordinated in Q² and Q³ units, Al was four-coordinated, and B was mostly three-coordinated. The rhenium additions did not have significant effects on the glass structure up to approximately 3000 ppm Re by mass, the maximum concentration that remained dissolved in glass. Rhenium likely exists in isolated anions in the interstices of the glass network, as evidenced by polarized Raman spectrum of the Re glass in the absence of sulfate. Analogous to in similar glasses, is a network modifier and above solubility forms alkali salt phases on the surface and in the bulk. Comparisons of phase separation and crystallization in containing borosilicate glasses can also be made to containing glasses.     

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.     

Dwell and Interface Defeat on Borosilicate Glass

We have conducted impact experiments using gold long rods into borosilicate glass and the measured the penetration velocity as a function of impact velocity. At sufficiently low-impact velocities, the glass target resists penetration and there is dwell; dwell is observed to approximately 450 m/s for bare glass. If a copper buffer is placed over the glass to eliminate the impact shock, significant dwell can be seen at impact velocities as high as 890 m/s. These impact velocities correspond to Bernoulli stresses of approximately 2.0 and 7.6 GPa, respectively. The paper describes the experimental data, and summarizes the results and our findings.     

A omparative Study of the Fatigue Properties of Synro and Borosilicate Glass

Comparative measurements have been made of the dynamic fatigue response of synroc and borosilicate glass specimens in water, using an indentation flaw technique. The results are presented in terms of a universal plotting scheme which allows for simple appraisal of the "lifetime" capabilities of the materials. Synroc is intrinsically stronger than borosilicate glass, but the fatigue susceptibilities are similar.     

Comparative Study of Rubidium and Cesium as Promoters in Carbon-supported Ruthenium Catalysts for Ammonia Synthesis

Sibunit-supported Ru-catalysts promoted with cesium or rubidium compounds have been comparatively studied with XPS. The cesium promoter interacts both with support and with active component. The absence of the promoter–support interaction in the case of rubidium provides a stronger interaction between promoter and active component compared to the cesium-based catalysts. These differences in the promoter–support and promoter–metal interactions are exhibited when a sequence of ruthenium and alkali introduction are changed.