基于光散射的实时气溶胶粒子形状识别技术研究

利用米氏散射理论和时域有限差分(FDTD)软件计算了不同大小、形状和折射率粒子的前向散射光场分布,分析了通过光强度分布和非对称因子反演粒子相关信息、区分粒形的可行性。研制了一台利用增强型CCD相机在线采集单个气溶胶粒子在5°~19°前向散射角范围内光场图样的装置。8μm粒径的聚苯乙烯球形粒子散射图样实验结果与理论计算对比较为吻合,验证了该装置的有效性。应用该装置对不同形状的气溶胶粒子进行检测,结果表明能够从散射图像和反演计算结果区分出球形、杆状和其他形状粒子。     

移动式应急处理导试水厂的设计与开发

针对现有导试水厂存在的问题,设计并开发了高度集成、具有多种功能及全自动控制的移动式应急处理导试水厂。移动式应急处理导试水厂采用预处理+混凝沉淀过滤+臭氧活性炭+消毒的工艺,可为水厂运行及升级改造提供技术支持。简述了导试水厂的工艺流程及系统组成,重点阐述了导试水厂的单元系统设计,并介绍了导试水厂的应用情况。     

基于AMESim的长距离管道液压系统动态特性与优化设计

为研究流体特性及管道参数等对长距离管道系统运行的影响,以海上采油树液压控制系统为原型,采用AMESim建立了长管道液压系统的仿真模型.研究了管道参数及流体属性对管道压力损失及动态特性的影响,并分析了影响长管道液压冲击的因素及改善方法.表明在管道直径、液压油属性不变的前提下,随着管道长度的增加,管道压力损失不断增大,系统负载的速度及位移响应时间增加;随着管道直径的减小,负载速度响应及位移响应逐渐降低,响应时间增加;随着粘度的增加,管道压力损失增加,负载响应时间增加;而流体密度对管道的压力损失、负载速度响应及负载位移响应的变化影响较小.随着管道长度的增加和管道直径的减小,压力冲击峰值有减小的趋势,通过安装蓄能器对压力冲击有明显的改善作用.分析了影响长管道液压系统动态特性的因素,优化了系统参数匹配,对长管道液压系统的设计提供了参考,对实际液压系统的设计具有指导意义.     

坝基不同倾角软弱夹层的破坏模式及D-C模型参数研究

坝基岩体中的软弱夹层对抗滑稳定影响重大,因此对其破坏模式及本构模型参数的研究具有重要意义。采用软弱夹层重塑样进行三轴压缩试验,下部未泥化部分采用泥化部分土掺入20%水泥代替,上部采用泥化部分土制样,泥化部分与未泥化部分交界面分别制成0°,30°,45°,60°倾斜面并作粗糙处理模拟实际界面特性。试验结果表明:含不同倾角结构面的软弱夹层试样临界角范围为58.3°～61.7°,当结构面倾角介于临界角范围之内时,软弱夹层试样沿结构面破坏,当结构面倾角位于临界角范围之外时,软弱夹层试样在上部泥化部分土中破坏;对软弱夹层试样三轴试验ε((σ_1-σ_3))–ε_1关系曲线进行线性拟合,结果表明,随围压增加,试样初始切线模量及极限破坏强度均增加,根据试验结果得出了相应的D-C模型参数并将其应用于坝基抗滑设计中,取得了良好效果。本研究成果对坝基软弱夹层的抗滑设计及同类软弱夹层工程性质的研究具有一定参考价值。     

正交异性钢桥面板结构体系的疲劳破坏模式和抗力评估

正交异性钢桥面板的疲劳问题属于包含多疲劳破坏模式的结构体系疲劳问题。基于这一本质特性,以典型的正交异性钢桥面板结构体系为研究对象,由结构体系的主导疲劳破坏模式出发,提出正交异性钢桥面板结构体系疲劳抗力评估的新方法。以纵肋与顶板焊接细节和纵肋与横隔板交叉构造细节为主要研究对象,设计8个足尺节段模型,主要包括传统纵肋与顶板焊接细节、新型镦边纵肋与顶板焊接细节和纵肋与横隔板交叉构造细节,通过模型试验研究了两类重要构造细节的主导疲劳破坏模式和实际疲劳抗力,在此基础上结合切口应力评估方法探讨正交异性钢桥面板构造细节切口应力S-N曲线方程、结构体系的主导疲劳破坏模式等关键问题。研究结果表明：传统纵肋与顶板焊接细节和新型镦边纵肋与顶板焊接细节的主导疲劳破坏模式均为疲劳裂纹萌生于焊根并沿顶板厚度方向扩展,二者的实际疲劳抗力基本相同;纵肋与横隔板交叉构造细节的疲劳破坏模式为焊趾开裂沿纵肋腹板方向扩展;对于研究对象而言,萌生于纵肋与顶板焊接细节焊根并沿顶板厚度方向扩展的疲劳破坏模式为控制结构体系疲劳抗力的主导疲劳破坏模式。     

HLC型乳化炸药连续化生产技术的应用

介绍了HLC型乳化炸药连续化生产线的实际应用情况。针对相配套的德国poly-clip自动灌装系统,提出了化学敏化的乳化炸药成品存在后效问题的解决办法,认为相适应的敏化剂加入量在900～950g·t-1之间。     

钻进过程孔内动态参数同步采集系统的研制

介绍了钻进过程孔内参数采集系统的组成原理、性能指标与特点、试验情况和应用前景。     

A ternary mechanism for the facilitated transfer of metal ions onto metal–organic frameworks: implications for the ‘‘versatility’’ of these materials as solid sorbents

Although metal–organic frameworks offer a new platform for developing versatile sorption materials, yet coordinating the functionality, structure and component of these materials remains a great challenge. It depends on a comprehensive knowledge of a “real sorption mechanism”. Herein, a ternary mechanism for U(VI) uptake in metal–organic frameworks was reported. Analogous MIL-100s (Al, Fe, Cr) were prepared and studied for their ability to sequestrate U(VI) from aqueous solutions. As a result, MIL-100(Al) performed the best among the tested materials, and MIL-100(Cr) performed the worst. The nuclear magnetic resonance technique combined with energy-dispersive X-ray spectroscopy and zeta potential measurement reveal that U(VI) uptake in the three metal–organic frameworks involves different mechanisms. Specifically, hydrated uranyl ions form outer-sphere complexes in the surface of MIL-100s (Al, Fe) by exchanging with hydrogen ions of terminal hydroxyl groups (Al-OH₂, Fe-OH₂), and/or, hydrated uranyl ions are bound directly to Al(III) center in MIL-100(Al) through a strong inner-sphere coordination. For MIL-100(Cr), however, the U(VI) uptake is attributed to electrostatic attraction. Besides, the sorption mechanism is also pH and ionic strength dependent. The present study suggests that changing metal center of metal–organic frameworks and sorption conditions alters sorption mechanism, which helps to construct effective metal–organic frameworks-based sorbents for water purification.     

Tunable Mission and Trichromatic White‐Emitting in Oxyfluoride Glasses by Utilization of Cu+ Ions as Multiple Energy‐Transfer Creators

A series of copper species, Tb³⁺, Mn²⁺ single‐ and co‐doped oxyfluoride glasses were synthesized by a melt‐quenching method. The photoluminescence properties of the glasses containing copper species were demonstrated. Results indicate that the blue‐green emission band peaking at 440 nm was observed, which was ascribed to the photoluminescence of Cu⁺ ions rather than the emissions of Cu²⁺ cations or Cu nano‐particles (Cu NPs) induced by local field effect (LFE) enhancement through surface plasmon resonance (SPR). The interaction mechanisms between Cu⁺ and Tb³⁺/Mn²⁺ have been systematically investigated, and significant enhancement of Cu⁺ emission and the energy‐transfer (ET) efficiencies of Cu⁺→Tb³⁺ and Cu⁺→Mn²⁺ were observed in glasses doped with SnO reducing agent. Furthermore, a wide‐range‐tunable emission and ideal white‐light fluorescence were realized in Cu⁺/Tb³⁺/Mn²⁺‐coactivated glasses by utilization of Cu⁺ cations as dual ET contributors from deep‐UV‐source to multiactivators. Our research further extends the understanding of the interactions between Cu⁺ and Tb³⁺/Mn²⁺ in amorphous materials.     

Thermal analysis and non‐isothermal kinetics of poly(ethylene glycol) with different molecular weight

This study focuses on comprehensively investigating polyethylene glycol (PEG) with different molecular weight. Thermal properties of the PEGs were investigated by differential scanning calorimetry (DSC), as well as gradual melting and freezing tests with thermocouples. Results show that the degree of PEG crystallization increased with the increasing of the molecular weight of polymers. The temperatures of pure PEG 1000 and PEG 1000‐PEG 600 blends ranged from 20 to 50°C. The apparent activation energy of pure PEG1000 was 300 kJ/mol, whereas that of the PEG blend was 239 kJ/mol. During the crystallization process, Avrami index n ranged from 5 to 3 and half‐crystallization time t_1/2 decreased with the acceleration of the crystallization rate R. This difference was due to the increase in polydispersity of the PEG system and decrease in the degree of crystallization. POLYM. ENG. SCI., 54:2872–2876, 2014. © 2014 Society of Plastics Engineers