Improvement of quantitative analysis of molybdenum element using PLS-based approaches for laser-induced breakdown spectroscopy in various pressure environments

An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments. An approach combined the normalization methods with the partial least squares(PLS) method are developed for quantitative analysis of molybdenum(Mo) element in the multi-component alloy,which is the first wall material in the Experimental Advanced Superconducting Tokamak. In this study, the different spectral normalization methods(total spectral area normalization,background normalization, and reference line normalization) are investigated for reducing the uncertainty and improving the accuracy of spectral measurement. The results indicates that the approach of PLS based on inter-element interference is significantly better than the conventional PLS methods as well as the univariate linear methods in the various pressure for molybdenum element analysis.     

Luminescent Solar Concentrators Based on Aggregation Induced Emission

A promising path to cost-effective photovoltaic (PV) systems is sunlight concentration. Over classical non-imaging geometrical concentrators, luminescent solar concentrators (LSCs) possess several advantages: low cost and weight, elevated theoretical concentration factors and aptitude to efficiently working with diffuse light without tracking or cooling equipment. Although considerable progress has been made, current LSC-PV systems attain low power conversion efficiencies due to critical processes that hinder their ability to deliver light to PV cells including fluorescence quenching due to dye aggregation. To overcome this issue, fluorophores with aggregation induced emission (AIEgens) have been proposed thanks to their high Stokes shift and quantum yield in the solid state. In this review, the current state of knowledge concerning the preparation of LSCs based on AIEgens is summarized with special reference on the strategy adopted aimed at increasing the absorption bandwidth while maximizing the solar collection.     

Investigation of the hydrogen induced cracking behaviour of API 5L X65 pipeline steel

The effect of microstructural features on the hydrogen induced cracking (HIC) susceptibility of two API 5L X65 pipeline steels were investigated by cathodic charging, hydrogen permeation and hydrogen microprint experiments. Microstructural evaluation after hydrogen charging revealed cracks at the mid-thickness (segregation zone) of both plates. However, more severe cracks were observed in the plate with higher dislocation density and residual stresses. The plate with lower plastic strain and more {111}-oriented grains had less severe cracks. Inclusions found along the crack path, comprising of Si-enriched oxides and carbides contributed to the initiation and propagation of cracks. The variation of the trapping behaviour and hydrogen diffusion through the plates were examined. The results confirmed that a higher ratio of reversible to irreversible traps contributes to increasing HIC severity in steels. Additionally, hydrogen transport through the steels was most prominent along the grain boundaries, indicating the importance of grain boundary character to HIC.     

Using a pulsed electric current to reduce the susceptibility of high-strength steel to the stress corrosion cracking caused by hydrogen

Under the tensile loading, the damage of metals in the corrosive medium is the most destructive and harmful. In this study, the stress corrosion cracking behavior of H-charged high-strength steel in 3.5 wt% NaCl solution after electropulsing treatment was investigated. The experimental results from elongation, yield strength, fracture morphology, and polarization curves all demonstrate the positive effect of the pulsed processing, as it reduced the susceptibility of steel to stress corrosion cracking by removing hydrogen by electropulsing. The reduction in hydrogen content of the pulsed high–strength steels was attributed to electromigration and increased system free energy, which drove the hydrogen atoms in the steel to de–trap and reduced the susceptibility to stress corrosion cracking.     

基于拓扑单向波导的电磁诱导透明效应研究

为了研究电磁诱导透明效应在拓扑单向波导中的表现，设计了一种基于磁性光子晶体的耦合谐振腔波导。通过对谐振腔位置的调控实现了具有单向性质的电磁诱导透明效应，并利用有限时域差分仿真证明了电磁诱导透明效应在单向拓扑波导中的相关特性。该研究可为拓扑波导中实现光延迟、光开关等提供参考。     

基于聚集诱导发光效应的高固低黏丙烯酸荧光树脂的制备及其性能研究

为了研制一种具有荧光功能特性的高固低黏羟基丙烯酸树脂。从聚集诱导发光效应（AIE）出发，将具有 AIE性质的二对丙烯酸四苯乙烯酯荧光分子通过自由基共聚连接于聚合物链段。由于聚合物链段对荧光分子化学键固定以及聚合物链的包裹束缚作用，导致荧光分子运动受限，从而实现涂层在紫外灯下荧光发光。通过荧光光谱的实时跟踪，探索高固低黏羟基丙烯酸树脂的合成以及固化规律。此外，由于聚合物链段对外界刺激具有实时响应性，从而间接影响了所连接的荧光分子的荧光发光行为。因此，文中也探索了涂层在外界温度与化学气体的影响下所发生的荧光变化的规律，以探索其在功能涂层中应用的可行性。     

巷道过陷落柱顶板安全技术措施

为了保证9109回风顺槽安全快速过X0陷落柱,保证过陷落柱期间顶板稳定性,七一煤矿通过技术研究,采用导硐分层爆破施工工艺,提出了“撞楔超前支护+注浆锚棚支护”联合加强支护措施。通过实际应用,过陷落柱期间顶板未发生冒落现象,顶板下沉量控制在0.13m以下,取得了显著成效。     

A yeast surface display platform for plant hormone receptors: Toward directed evolution of new biosensors

Small-molecule biosensors have major applications in biotechnology and medicine but remain difficult to engineer. Plant hormone receptors represent an attractive platform for engineering such biosensors because their chemically induced dimerization architectures naturally decouple small-molecule sensing and sensor actuation. Rapid biosensor engineering will require quantitative high-throughput screening methods. Here we develop a yeast surface display (YSD) platform for the PYR1/HAB1 abscisic acid sensor of Arabidopsis thaliana. We extensively optimized PYR1 surface display, HAB1 purification, and binding reaction conditions. Our system reproduces previous results with wild-type and engineered receptors, and a mathematical analysis of the PYR1/HAB1 system allows us to infer all binding constants. Critically, we find that a previously engineered PYR1 receptor with altered ligand specificity binds HAB1 with identical affinity, suggesting that substantial reengineering of the PYR1 binding pocket does not compromise sensor actuation. This YSD platform for A. thaliana PYR1/HAB1 will facilitate future biosensor engineering efforts.     

CYP2D6基因多态性对托烷司琼预防化疗所致恶心呕吐效果的影响

肿瘤对人类健康造成很大威胁。化疗作为一种全身性的治疗方法，在肿瘤治疗中的地位不可动摇。化疗所致恶心呕吐（chemotherapy induced nausea and vomiting, CINV）是化疗过程中常见的不良反应，严重影响了患者的情绪、生活质量和肿瘤的控制。CINV的防治对肿瘤患者来说非常重要。托烷司琼是较常用的5-羟色胺Ⅲ亚型（5-hydroxytryptamine type 3, 5-HT3）受体拮抗剂，在防治CINV方面具有很好的临床效果，但仍有部分患者使用托烷司琼后效果不佳。越来越多的研究表明这些个体差异可能与基因多态性密切相关。本文就细胞色素P450 2D6（cytochrome P450 2D6, CYP2D6）基因多态性对托烷司琼预防CINV效果的影响作一综述，以期为基因多态性指导下的临床个体化用药提供思路。     

High‐performance printable paper‐like composites derived from plastic flexible film wastes

Owing to lack of proper recycling methods, plastic flexible film wastes are usually directly discarded or incinerated, which brings about severe environmental pollution. Therefore, converting plastic wastes into value‐added products has received more and more attention in recent years. In this work, paper‐like composites derived from plastic flexible film wastes were prepared via the thermally induced phase separation method by adding polyethylene‐graft‐maleic anhydride (PE‐g‐MAH) as a compatibilizer and fumed silica as an additive. The resulting paper‐like composites were characterized by SEM and infrared spectroscopy. Other properties such as mechanical properties, thermal properties, whiteness, printability and adsorption performance were also tested in detail. It was found that remarkable enhancements in mechanical, thermal and printable properties of the paper‐like composites were obtained when nano‐SiO₂ loading was 2.5–3 wt%. Uniformly distributed holes that can endow good printability by providing space for ink or other functional molecules were observed by using SEM. Furthermore, the CIE whiteness value of the resulting composites can reach 91.6%–96.7% on adding nano‐SiO₂. Additionally, the paper‐like composites integrating nano‐SiO₂ and PE‐g‐MAH exhibited good solid ink affinity and high water or oil adsorption capacity. Thus, according to this research, high‐performance printable paper‐like composites used as major components of multifunctional papers can be prepared based on plastic flexible film wastes. © 2019 Society of Chemical Industry