Refractive index of soft contact lens materials measured in packaging solution and standard phosphate buffered saline and the effect on back vertex power calculation

PurposeTo measure the refractive index (RI) of commonly available soft contact lens (CL) materials, their packaging solutions and compare to the manufacturers’ nominal RI. The relationship between RI versus water content, and the effect of inaccurate RI when converting lens power measured in solution to in-air back vertex power were examined.MethodsThe RI of 18 single vision soft CL materials were measured using CLR 12–70 digital refractometer. Three lenses of each material were measured, in their packaging solution and then after soaking in standard phosphate buffered saline (PBS). The RIs of packaging solution were also measured. Accuracy requirements for correct wet to dry power conversion based on thick lens formula were projected.ResultsThe standard deviation between three samples was less than 0.005. The measured RI ranged from 1.3744 ± 0.001–1.4265 ± 0.0004 for PBS soaked and from 1.3739 ± 0.0003–1.4264 ± 0.0024 for packaging solution soaked materials. Comparing nominal with mean measured PBS and packaging solution RIs, 5 and 3 lens materials, respectively, fell outside ISO tolerance. The packaging solution RI of DailiesAquaComfortPlus had the largest difference of 0.0040, compared to RI of standard PBS. For converting lens power measured in PBS to in-air power, the difference between measured and nominal RI of 0.0104 would result in wrongly calculated in-air power 0.99 D for a -6.00 D lens.ConclusionThe CLR 12–70 is reliable and accurate refractometer for the measurement of soft CL materials. Accurate RI measurements are of relevance with increased use of wavefront sensors to measure lens power while they are immersed in solution. Even small errors in solution or material RI can lead to significant errors in converted in-air power. To obtain valid in-air lens power results, measurement conditions must match the material and solution RIs used for the conversion.     

Modeling the effects of loading scenario and thermal expansion coefficient on potential failure of cryo-compressed hydrogen vessels

A multiscale thermomechanical model for a simplified Type-3 cryogenic, compressed-hydrogen (H₂) storage vessel is described in this paper. The model accounts for the temperature-dependent elastic-plastic behavior of the vessel's carbon/epoxy composite overwrap and aluminum alloy liner. The homogenized thermo-elastic-plastic behavior for the individual laminae of the vessel layup is obtained using an incremental Eshelby-Mori-Tanaka approach associated with a micromechanical failure criterion to predict laminar failure while a standard elastic-plastic constitutive model is used to describe the behavior of the typical aluminum alloy assumed for the liner. The vessel's response to external loadings is modeled using a finite element method. Four loading scenarios, representing four thermomechanical cycles applied to the vessel, are analyzed to evaluate constituent and laminar stresses as well as the associated failure criterion during the cycle according to these scenarios. The model can provide helpful guidance to mitigate thermal stresses by selecting a suitable loading scenario, optimizing the layup, and tailoring the thermomechanical properties of the resin matrix.     

冷轧高强集装箱板轧制稳定性控制技术

 冷轧高强集装箱板由于其屈服强度、成形性能及尺寸精度的要求,对冷轧轧制稳定性和板形控制提出极大挑战。针对某钢厂薄规格冷轧高强集装箱板生产过程存在的肋浪和边裂情况进行分析,采用试验方法研究了热轧带钢库区冷却过程对钢卷温度及性能均匀性的影响,利用数值模拟的方法研究了该钢种在UCM机型冷轧轧制过程中带材变形特征,揭示了带材浪形和边裂的并发机理,同时分析了不同工艺对带钢变形均匀性的影响规律。结合理论及仿真分析,提出了针对热卷性能均匀性及酸轧轧制稳定性的优化方案,改进后冷轧板形质量明显提高,带材边裂缺陷完全消除,冷轧高强集装箱板的轧制稳定性及产品质量均得到大幅提升。     

Designing inorganic electrolytes for solid-state Li-ion batteries: A perspective of LGPS and garnet

Solid-state Li-ion batteries (SSLBs) are promising next-generation energy storage devices with high energy density and enhanced safety. The solid-state electrolyte (SSE) is a key component for delivering the desired electrochemical performance characteristics. This article provides a brief review of the discovery, synthesis, structure, ion-conduction mechanism, and application of LGPS-type and garnet-type Li ion conductors as two representative SSEs, aiming to extract principles for the future design and discovery of favourable solid-state Li-ion electrolytes for SSLBs. Recent advances in strategies to address the SSLB challenges are also discussed. Finally, a perspective on the future research directions of SSLBs is provided.     

Evaluation of the specific radioactivity of 40 elements created by nuclear transmutation of fission products

A burnup calculation was performed to analyze Après ORIENT process which aims at creating highly-valuable elements by nuclear transmutation of fission products (FPs) separated from LWR spent nuclear fuels. In this paper, numerical evaluation of the specific radioactivity of 40 created elements, from reloaded each FP element, with atomic number from 31 to 70 at the end of the time of 5-year-cooling after the irradiation for 1125 days in each LWR and FBR was carried out. These 40 created elements were classified in 6 categories according to levels of the specific radioactivity and the length of additional cooling period, which was needed for the specific radioactivity to decrease below the exemption level defined by International Atomic Energy Agency. As a result, created ₃₁Ga, ₃₂Ge, ₃₃As, ₃₅Br, ₆₈Er, and ₇₀Yb did not contain any radioisotopes at the end of the 5-year-cooling. It should be noted that created ₃₇Rb, ₅₇La, and ₆₀Nd had much lower specific radioactivities than natural composition of them. Moreover, specific radioactivities of created ₄₀Zr, ₄₂Mo, ₄₄Ru, ₄₆Pd, ₄₉In, and ₅₄Xe were sufficiently lower than their exemption levels at the end of the 5-year-cooling. On the other hand, created ₃₉Y, ₄₅Rh, ₅₀Sn, ₅₂Te, ₅₈Ce, ₅₉Pr, ₆₅Tb, and ₆₆Dy needed additional cooling period less than 10 years until their specific radioactivities decreased below their exemption levels. Then, each additional cooling period required for created ₄₈Cd, ₅₁Sb, ₆₄Gd, and ₆₉Tm was estimated at 10–100 years. Additionally, specific radioactivities of other 13 created elements would not decrease below their exemption levels even if they had been stored for 100 years. There could be significance to create important elements as resources classified in first 4 of the 6 categories defined in this paper, by nuclear transmutation of fission products. In consideration of the efficiency of creation, the radioactivity, and the importance as resources of each product, ₄₄Ru, ₄₆Pd, ₅₂Te, ₆₀Nd, and ₆₆Dy were specially selected as the most important created elements to be more researched in the future Après ORIENT program.     

临兴区块致密砂岩气储层损害机理及钻井液优化

致密砂岩气储层钻井过程中,钻井液入侵将造成严重的储层伤害难题。通过岩心分析技术、岩心流动实验等系统分析了临兴区块致密砂岩气储层主要损害机理,统计并分析了现场钻井液存在的技术难题,并优化出具有良好性能的致密砂岩气储层保护钻井液。研究结果表明,临兴区块致密砂岩气储层岩石具有中-粗砂状结构,胶结致密,孔喉细小,含敏感性黏土矿物,储层潜在严重的水锁伤害与中等偏强的水敏性及应力敏感性损害（临界压力为7.0 MPa）,潜在中等偏弱的速敏性（临界流速为0.75 mL/min）、盐敏性（临界矿化度为7500 mg/L）、碱敏性（临界pH值为10.0）及土酸敏感性损害;临兴区块主要存在储层损害、钻井液漏失、井眼垮塌、摩阻扭矩大与井眼清洁等钻井液技术难题。优化出的钻井液封堵性能良好,滤液表面张力低（23.3 mN·m-1）,能减少固相侵入,削弱水锁效应,提高岩石渗透率恢复值至91.3%,具有良好的储层保护性能。现场应用结果表明,该储层保护钻井液完全满足复杂井段或水平井段钻进的钻井液技术要求。      

Iridium-based light-emitting electrochemical cells containing ionic liquids in the luminous layer

To fabricate transition metal complex-based LECs (light-emitting electrochemical cells), ([Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ was synthesized and used as a luminous material and ILs (ionic liquids) were incorporated into a luminous layer, in which two types of ionic liquid were used; 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF₆) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF₄). ILs were added to a [Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ luminous layer to improve ionic conductivity and light intensity. Both ILs significantly increased the current density and luminance. Due to the small molecule of BF₄^?, turn-on time was reduced and ionic conductivity was increased. However, the device stability was sacrificed. High current efficiency of 34.5 cd/A was investigated at 7 V of BMIMPF₆-doped luminous layer. The LECs based on [Ir(ppy)₂(5,6-dime-1,10-phenthroline)]PF₆ gave yellow emission color when ILs were added into light-emitting layer, and no significant change of color has been found in this study.     

空分透平冷箱高含氧事件的探讨与分析

介绍了某空分项目中遇到的一起低温透平冷箱高含氧事件问题,分析了氧气泄漏的可能性,并用泄漏检查确定了漏点,解释了高含氧的原因,最后对预防冷箱内法兰连接出现泄漏提出了建议。     

液压支护长壁法开采缓倾斜薄铁矿体围岩变形与破坏规律研究

基于缓倾斜薄铁矿体特征,提出用液压支护长壁法开采缓倾斜薄铁矿体新方法。以官店铁矿凉水井大庄矿段-8’至-16’线范围矿体为研究对象,采取相似模拟方法对围岩应力、位移和塑性区域变形与破坏规律进行实验研究;采用数值模拟对工作面采场围岩应力、位移和塑性区域变化进行模拟研究,并与相似实验结果进行对比分析。结果表明:围岩破坏具有明显间隙和突变性,断裂方向相互平行;位置不同围岩在垂直方向上断裂步距不同;工作面端部受剪切作用明显,空区顶部受拉作用突出;靠近工作面下沉值较小,呈抛物线型。     

基于深度脱水的污泥干化焚烧工艺

介绍了污泥调质机械压滤深度脱水后入炉焚烧的污泥处置工艺,与现有几种污泥处置工艺能耗比较表明深度脱水污泥干化工艺能耗低、系统简单,同时结合该工艺的实际运行情况,详细总结了深度脱水前后污泥成分和形状的变化,最后对深度脱水后污泥循环流化床焚烧系统及主要技术经济指标进行了分析,为同类湿污泥处理提供借鉴和参考。