Receptor-Based Fluorescence Polarization Assay to Detect Phthalate Esters in Chinese Spirits

This work developed a fluorescence polarization (FP) assay for detection of phthalate esters (PAEs) in Chinese spirits. A mouse-derived recombinant peroxisome proliferator-activated receptor α ligand binding domain (mPPARα-LBD*) and a fluorescent-labeled fatty acid (C4-BODIPY-C9) were employed as recognition element and fluorescent tracer, respectively, providing the limits of detection (LODs) below 11.2 μM for the 10 PAEs tested in buffer. Chinese spirits spiked with DEHP and DBP could be positively detected in combination with simple pretreatment, with recoveries ranging from 76.9 to 87.0 % and with coefficients of variation below 10 %. Additionally, the mechanisms of mPPARα-LBD* binding to PAEs were investigated by using molecular simulation approach. The results suggested that the proposed method was reliable for monitoring PAEs in Chinese spirits.     

A 2D pillar-layered coordination framework with meso-helix constructed from imidazole-4,5-dicarboxlylate and terephthalate

A new pillar-layered coordination framework [Er(H₂O)(C₅H₂N₂O₄)(TA)_0.5]_n (1) has been hydrothermally synthesized by employing imidazole-4,5-dicarboxlylate (H₃IDC) and terephthalate (H₂TA) and structurally characterized. Single crystal X-ray diffraction analysis reveals that compound 1 exhibits the 2D pillar-layered coordination framework with meso-helical character constructed from auxiliary ligand TA^2? (that is, pillar) bridging two [Er(HIDC^2?)]_n layers (namely, Δ- and Λ-layers), which is the first example of lanthanide coordination framework including imidazole-4,5-dicarboxlylate and terephthalate. Meanwhile, the thermogravimetric analysis shows compound 1 has high thermal stability.     

宽频超声衰减法测量河流泥沙粒径分布

为了研究宽频超声波通过河流泥沙悬浊液的声衰减谱中包含泥沙的颗粒粒度信息,采用超声耦合相模型和散射模型的叠加描述河流泥沙悬浊液中超声衰减行为,宽频超声换能器测量得到2～7.5MHz间泥沙悬浊液声衰减谱,结合独立模式的最优正则化反演算法,获得了相同体积浓度、不同粒径分布下和相同粒径分布、不同体积浓度下泥沙的颗粒粒径分布。结果表明,宽频超声衰减法能较好地区分3种不同粒径分布的泥沙,并且在体积浓为3.8%～8.5%范围间,测量得到的平均粒径受浓度变化影响较小。将超声法测量结果与显微镜图像法测量结果相比较,两种方法得到的粒径分布趋势较为一致,平均粒径较为吻合。     

气-液柱状旋流式分离器控制策略综述

随着气-液柱状旋流式分离器(GLCC)的广泛应用,对其分离效果的要求也越来越高。通过在GLCC分离装置中引入控制系统,可以减小内部液位压力的波动,从而保证良好的气液分离效果。控制系统的优劣决定了气液分离效果的好坏,进而影响整个计量系统的性能。总结了用于GLCC的多种控制策略,并对未来控制策略的研究和应用进行了展望。     

Recent advances in hydrogel-based anti-infective coatings

Bacterial infections associated with biomedical devices and implants have posed a great challenge to global healthcare systems.These infections are mainly caused by bacterial biofilm formed on the surface of biomaterials,protecting the encapsulated bacteria from conventional antibiotic treatment and attack of the immune system.As the bacterial biofilm is difficult to eradicate,bactericidal and antifouling coatings have emerged as promising strategies to prevent biofilm formation and subsequent infections.Hydrogels with three-dimensional crosslinked hydrophilic networks,tunable mechanical property and large drug-loading capacity are desirable coating materials,which can kill bacteria and/or prevent bacterial adhesion on the surface,inhibiting biofilm formation.Herein,we review recent developments of hydrogels as anti-infective coatings.Particularly,we highlight two chemical approaches(graft-from and graft-to),which have been used to immobilize hydrogels on surfaces,and present advances in the development of bactericidal(contact-killing and antimicrobial-releasing),antifouling(hydrophilic polymer network)and bifunctional hydrogel coatings with both bactericidal and antifouling activities.In addition,the challenges of hydrogel coatings for clinical applications are discussed,and future research directions of anti-infective hydrogel coatings are proposed.     

Control chart for monitoring the coefficient of variation with an exponentially weighted moving average procedure

The coefficient of variation (CV) of a population is defined as the ratio of the population standard deviation to the population mean, which can be regarded as a measure of stability or uncertainty and can also indicate the relative dispersion of data to the population mean. This paper proposes a new exponentially weighted moving average chart for monitoring CV, which is constructed by truncating those negative normalized observations to 0 in the traditional exponentially weighted moving average CV statistics. The implementation and optimization procedures of the proposed chart are presented. The new chart is compared with some existing CV charts by means of average run length, and the comparison results show that the new chart outperforms other charts in most cases. Two examples illustrate the use of this chart on real data gathered from a metal sintering process and from a die casting hot chamber process.     

轮胎爆裂失效分析

直升机后起落架轮胎在地面例行充气过程中发生爆裂,通过对轮胎外观检查,裂纹扩展走向分析,判断裂纹起源位置,对轮胎壁厚、沟槽深度进行测量,分析轮胎磨损情况,对轮胎开裂位置处的断口宏微观形貌进行分析判断,确立开裂模式,结合轮胎所用材料特性及轮胎表面微裂纹特征给出轮胎爆胎的主要原因:轮胎爆裂起源于胎面\     

硅酸铝微珠在人造花岗石中的应用

长期以来,人造花岗石普遍是用热固性树脂与填充料、增强材、内部脱模剂、硬化剂等辅助原料配合而成的树脂混合料注入所需形状的金属模具,加热固化而成.为防止强度降低,成形制品的厚度通常为10～ 30mm.由于板体规格越大,质量越重,不便于生产和安装过程中的装卸.因此,尽可能减少板体厚度,使其轻质.但板体变薄,其自身强度降低,用...     

Deep Convolutional Network with Pixel-Aware Attention for Smoke Recognition

Fire Technology - Deep convolutional networks have significantly improved the performance of smoke image recognition. However, the trained spatially-shared weights are applied to all pixels...     

城市化进程中历史遗存片断的可持续保护与利用——以连云港凤凰古城保护开发为例

本文针对城市化进程中城市历史遗存常遭破坏性更新的现象进行分析,并结合凤凰古城的改造规划,对历史遗存片断的可持续保护与利用的原则、措施进行探讨。