栾川地区尾矿库的管理与安全运行

对栾川地区几十座尾矿库的基本情况进行了分析,找出了存在的问题,提出了解决问题的办法和应采取的措施,对尾矿库的管理和安全运行有一定的指导意义.     

Helium plasma source time-of-flight mass spectrometry: off-cone sampling for elemental analysis

In this paper, an atmospheric pressure, helium microwave-induced plasma (MIP) ion source coupled with an orthogonal acceleration time-of-flight mass spectrometer (TOFMS) is explored for elemental analysis. Studies of the relationship between ion signals and sampling distance of the MS reveal that background signals can be suppressed dramatically without sacrificing the signal intensities of analytes when the microwave plasma plume is off the tip of the sampler orifice. This "off-cone" ion sampling mode provides a technique to obtain nearly "clean" background spectra and, thus, eliminates the spectral interference from entrainment air and the working-gas species, making it possible to sensitively determine isotopes that suffered from spectral interference in ICPMS and MIPMS (such as 40Ca, 52Cr, 55Mn, and 56Fe). On the other hand, since the high-temperature plasma is kept away from the sampler aperture, off-cone sampling places little demand on the cooling device and the lifetime of the sampler plate can be extended. The instrumental system can provide a fairly good mass resolution of 1100 (fwhm). The detection limits (3sigma) in the tens of picograms per milliliter level for the elements studied can be achieved with a digital oscilloscope. These detection limits can be easily improved with an advanced detection system, which is currently available in commercial markets.     

Development and evaluation of a glow discharge microwave-induced-plasma tandem source for time-of-flight mass spectrometry

In this work, a new glow discharge, microwave-induced-plasma (GDMIP), tandem ion source was developed, characterized, and used in conjunction with time-of-flight mass spectrometry. This tandem source was designed to be simple and compact The GD and the MIP unit are independent and demountable, providing flexibility in tuning and operating. The microwave plasma can be formed with very low power (a few watts) and overlapped with the glow discharge. The discharge current increased with the addition of microwave discharge when the GD was operated in constant-voltage mode, and the amplitude of the current increase was found to be related to microwave power, discharge pressure, and sampling distance. With the addition of microwave discharge, significant signal enhancement was achieved under a discharge pressure of 2.0 Torr and a discharge voltage of 500 V with 2.0-mm sampling distance. Enhanced factors of analyte signals ranging from approximately 1 to nearly 10 could be obtained with MIP boosting, while no significant change in noise level was observed. This new tandem source provides improved performance in direct solid sample analysis.     

有机酯水玻璃砂性能研究及应用

通过强度、发气性、表面安定性测试,研究了两种有机酯水玻璃砂的性能,结果表明,SS10有机酯水玻璃砂的硬化性能优于MDT901有机酯水玻璃砂。当温度低于0℃时,前者的硬化速度明显降低。而后者的硬化速度可通过添加调节酯加速。     

聚酯热熔胶溶胀制粉法的研究

聚醋热熔胶在其溶剂一沉淀剂混合液中加热“溶胀”后。再利用搅拌破碎而冷却成粉的方法。通过计算得到聚酯胶的溶解度参数(δ=21.8),参照比值选择溶剂和沉淀剂,并确定混合液的配比。文中还时制粉工艺和混合原料制粉的性能进行了研究。     

一种鲁棒渐近跟踪控制器设计的新方法

至于线性不确定系统，本文基于Ｒｉｃｃａｔｉ方程提出了一种新的鲁棒渐近跟踪控制器的设计方法。对于允许的系统参数变化，有使系统的输出渐近跟踪某一参考输入，数值算例说明了本文方法的有效性。     

偶联剂对B_4C／PP共混体系的增容作用

Ｂ４Ｃ／ＰＰ共混纤维是重要的防中子辐射材料。通过Ｂ４Ｃ／ＰＰ共混体系流变性能及纤维的形态结构性能的研究，分析了钛酸酯偶联剂在Ｂ４Ｃ／ＰＰ共混体系中的增容作用，表明了最佳偶联剂的品种和用量分别为ＮＤＺ－１０１和１．５～２．５％．     

分段线性多开关时间次优控制系统的设计

提出一种新的时间次优控制系统的设计方法，利用分段线性近似构造了一个结构比较简单的开关函数，使系统在最大程度上逼近时间最优控制；同时在进入奇异振荡工作状态之前，自动由ＢＢＣ方式切换成线性控制，解决了切换试凑的困难。应用本文方法设计了某水下航行器航深时间次优控制系统并进行了仿真研究，仿真结果表明了本文方法的有效性。     

雷电脉冲对导体平面窄缝隙穿透的时域分析

研究无限大导体平面任意形状窄缝隙对雷电脉冲的时域穿透特性。文中以窄缝隙内等效面磁流为未知量建立了时域微积分方程，寻求了一种稳定有效的数值求解方法，编程计算了穿透电场时域特性，并给出了分析结论。     

细长管玻璃钢内涂层去除工艺与振动计算

介绍了一种新的细长管内玻璃钢涂层的去除工艺方法和切削头结构，并进行了模型的建立、振动计算和参数分析。