羧甲基纤维素阳离子化衍生物的研究现状

羧甲基纤维素阳离子化改性是制备性能优良的天然两性高分子的重要方法之一。文章综述了迄今为止羧甲基纤维素阳离子化改性所用的阳离子单体的主要类型及其接枝的若干主要途径,其中包括自由基型接枝共聚、高分子侧基反应、聚合后功能化等三大类。     

聚合物熔体在圆锥短口模的挤出胀大方程

深入讨论了聚合物熔体在不同长径比、不同角度圆锥短口模的挤出胀大现象及机理，利用生产用挤出机进行不同角度的圆锥短口模实验。结果表明，圆锥短口模挤出过程中，熔体在收敛流道受到拉伸流变，导致强烈的入口弹性效应，表现为熔体在短口模挤出时显著的挤出胀大。理论和实验研究结果进一步表明不同圆锥口模入口角对实验材料表现出有不同的挤出胀大值。     

Effect of Grain Boundaries on Thermal Conductivity of Silicon Carbide Ceramic at 5 to 1300 K

The thermal conductivity of a SiC ceramic was measured as 270 W·m⁻¹·K⁻¹ at room temperature. At low temperatures ( T < 25 K), the decrease in the conductivity was proportional to T ³ on a logarithmic scale, which indicated that the conductivity was controlled by boundaries. The calculated phonon mean free path in the ceramic increased with decreased temperature, but was limited to ∼4 μm, a length almost equal to the grain size, at temperatures below 30 K. We concluded that the thermal conductivity of the ceramic below 30 K was influenced significantly by grain boundaries and grain junctions.     

JOB-9003炸药"激热"冲击损伤破坏及超声特征

进行了未经热处理的JOB-9003塑料粘结炸药(PBX)标准压缩试样的"激热"冲击损伤破坏试验,对试样热冲击试验前后的超声波特性参量进行了检测,试验显示出JOB-9003炸药存在一个明显的"激热"冲击损伤破坏临界温度差,并获得了试样热冲击损伤破坏的超声波参量特征.     

Experimental Evaluation of the Acceptor-States Compensation in Positive-Temperature-Coefficient-Type Barium Titanate

Experimental evidence shows that the acceptor-state levels in Sb-doped positive-temperature-coefficient-type BaTiO₃ are compensated up to a critical acceptor-state density. Using the slope of the natural logarithm of the resistivity with respect to 1/ T , instead of maximum resistivity as a measure for the acceptor-state density, it is possible to estimate this critical value. The value obtained (4.2 × 10¹⁷ m⁻²) is believed to be the first reported estimate based on experimental data. It is in good agreement with the estimate of 6 × 10¹⁷ m⁻² (first reported by Jonker) obtained from the spontaneous polarization of BaTiO₃. This shows that the ferroelectric behavior of BaTiO₃ is indeed a feasible explanation for the low resistivity below the Curie point, as proposed by Jonker.     

一种含壳聚糖的有机硅纺织柔软剂的研制

以三甲胺、环氧氯丙烷、壳聚糖为原料，合成了N-壳聚糖季铵盐；并将其与氨基硅油、三种非离子型表面活性剂、一种有机硅两性表面活性剂进行复配，制成了一种新型有机硅柔软剂。经检测，产品的离心稳定性、酸碱稳定性及阴离子型表面活性剂稳定性较好；经其整理的纯棉白布不仅具有良好的柔软性和吸湿性，而且具有一定的抗茵活性。     

基于移动互联网的养殖平台开发与应用

将移动互联网和物联网信息关键技术应用于水产养殖中,整合渔业新闻动态、水产养殖技术、手机信息服务等功能模块,为实现健康养殖的渔业生产保驾护航,不仅大大降低了生产人员的劳动强度,方便了技术人员对数据的收集和分析,并提高了养殖动物病害预警的能力,同时也配合了水污染治理工作。     

城轨车载信号系统线路调试试验研究

本文介绍了一种通用的城轨车辆车载信号系统线路试验装置,用于车辆组装完成后的调试试验。针对轨道列车车载信号系统在车辆上的布置规律,综合不同供货厂家的车载信号系统与车辆的电气接口特点,制作通用的信号系统线路试验装置。通过输出和采集开关量、模拟量、频率指令,检测车辆信号系统线路的状态,并采用无线通讯方式,实现对各试验装置的远程监控和数据存储。     

The Effects of Experience and Strategy on Visual Attention Allocation in an Automated Multiple-Task Environment

Operators and users interacting with computer environments often have to deal with multiple tasks at once, responding to each in series. Diagnostic automation, that is, automation that alerts users when and where to look, has been suggested to support the unique challenges of multiple task environments: activating tasks, switching between tasks, and tasks interfering with each other. Automation is not always reliable, however. Because of the common interaction with novel systems and the importance of training, the Simultaneous Task Environment Platform program—a multiple-task environment—was developed to understand the effects of experience on interaction with these automation-supported systems, as well as what strategies were developed. It was found that participants became more efficient with experience only when they interacted with higher reliability automation. Furthermore, the strategies participants developed focused on the differences between tasks and patterns across those tasks. Automated systems training should be sure to employ these findings.     

徐州市云龙湖水质监测与评价

以云龙湖东西两湖区为对象,研究其不同功能区水质状况.在云龙湖东湖、西湖区各设置3个采样点,监测水体中总氮、总磷、高锰酸盐指数、氨氮、溶解氧和透明度指标;分别使用模糊识别法和特里指数法对水体进行水质评价与富营养化评价.评价结果表明：云龙湖水质级别为Ⅲ类,其中TN、TP超标明显,水体已呈现轻度富营养化;不同功能区水质差异明显,东湖区水质优于西湖区,云龙湖功能区划分对水体有显著影响.