电弧等离子体喷射法直接制备金属有机聚合物

金属有机聚合物一般通过金属有机化合物单体聚合来制备,但由于单体制备困难、性能不稳定,其发展受到限制.本文提出了用低压直流电弧等离子喷射法将有机单体和金属直接合成金属有机聚合物薄膜的方法,成功地制备了铜与丙烯腈、丙炔腈的金属有机聚合物薄膜.红外光谱和电子能谱的分析结果表明:聚合物薄膜中含有环状共轭结构,铜与聚合物以共价键、配位键结合.用改进的四探针法进行测量,铜与丙炔腈聚合物薄膜的电阻率在10~0～10~3Ω·cm范围内,铜与丙烯腈聚合物薄膜的电阻率在10~6～10~7Ω·cm范围内。     

混凝土湿喷台车臂架振动模态分析

以国内某公司喷浆台车SPTC25为研究对象,首先利用陀螺仪和加速度传感器在施工现场进行动力学测试,采集到关于臂架在实际施工时的角速度和加速度的时间历程曲线。然后通过数据处理和分析计算,得到臂架在仰俯工况下的振动频率和振幅,分别为1.18 Hz和0.092 m,回转工况下的振动频率和振幅分别为0.98 Hz和0.073 m。其次,对湿喷台车臂架建立了准确的有限元模型,并且进行了模态仿真分析,得到前三阶模态的固有频率和振型。结合隧道施工时的实际操作数据统计,最终得出结论,臂架在施工过程中长时间处于共振状态,使得振幅过大,这是臂架疲劳开裂的主要原因,也为后续湿喷台车臂架的研发和优化提供了新的分析思路。     

三维荧光光谱结合二阶校正方法同时测定水中两种酚类

水是生命之源,人们日常生产生活离不开水。近年来水体污染日趋严重,已经危害到人类的健康。酚类化合物(Phenolic Compound)是一种广泛存在且很难降解的有机污染物,指的是芳香烃中苯环上的氢原子被羟基取代所生成的含羟基衍生物,毒性很强,对动植物及人类的生命活动有严重危害。实验研究对象选取间苯二酚(resorcinol,RES)和对苯二酚(hydroquinone,HYD)来配制待测样本,并且在其中3组预测样本中加入苯酚(phenol,PHE)作为干扰物,待测样本和空白溶剂分别用FS920稳态荧光光谱仪(edinburgh instruments,EI)扫描得到荧光光谱数据。对所得到的数据通过扣除空白溶剂法来消除拉曼散射的影响,得到的数据在消除干扰的同时最大程度保留下来原光谱所包含的重要信息。校正后光谱变得更加圆滑,荧光强度显著增强,因此,校正处理后的光谱信息更为准确。利用三维荧光光谱(EEM)结合平行因子分析(PARAFAC)和交替惩罚三线性分解(APTLD)两种二阶校正方法,分别完成在不含干扰物和含有干扰物、同时激发-发射光谱严重重叠时对间苯二酚、对苯二酚的快速、直接、准确测量,并给出定性、定量分析结果。PARAFAC算法对混合体系的组分数(即化学秩)较敏感,组分数选取过大易使其陷入计算"沼泽",迭代次数增多,计算耗时变长。故本文利用核一致诊断法(CORCONDIA)预估计出准确的组分数,保证PARAFAC算法更加快速准确。从定性分析结果知,当不含有干扰物时,PARAFAC能够准确分辨出间苯二酚和对苯二酚,二者荧光峰位置极为接近,很难用传统方法分辨,体现出将三维荧光光谱技术与化学计量学二阶校正方法相结合所具有的"二阶优势";定量分析结果给出,在有干扰物共存时,分别应用两种二阶校正法解析光谱数据结果显示:PARAFAC的浓度预测回收率为93.4%±0.5%~97.1%±1.0%,预测均方根误差小于0.190 mg·L^-1;APTLD的浓度预测回收率为95.9%±1.6%~97.2%±0.8%,预测均方根误差小于0.116 mg·L^-1,通过比较两种方法性能得:PARAFAC对待测物组分数敏感,对待分解的光谱数据严格线性要求高;而APTLD对混合物组分数不敏感,计算速度快,抗噪声能力较强,结果稳定,具有较明显的优势。     

基于精确时间协议的HL-2M装置定时同步网络研究

基于HL-2M装置对时序精度的要求,参考ITER的设计方案,设计了基于精确时间协议(PTP)的HL-2M分布式时间通讯网络,使HL-2M装置的时钟同步和事件触发的精度从微秒级提高到亚微秒级,最终优于100ns.     

汽配件颜色喷涂顺序问题的TSP转化与建模

汽配件颜色喷涂顺序问题通常以生产线上相邻汽配件颜色切换次数少为最优目标,以进一步降低生产成本.该类问题具有所有汽配件都必须喷涂一次且只喷涂一次的特点,为此提出了TSP转化与建模的方法.将待喷涂汽配件定义为TSP顶点,任意两个待喷涂汽配件的颜色切换定义为顶点的距离,仿照TSP问题构建0-1规划模型;类似于顶点距离,将某些...     

Characterization of laser sealed coatings of yttria partially stabilized zirconia

The present paper reports an experimental investigation based on X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and wavelength dispersive spectroscopy (WDS) analyses of phases formed after laser sealing of plasma sprayed coatings of 8.5 wt% yttria partially stabilized zirconia (YPSZ). X-ray diffraction and X-ray step-scanning analyses showed that the plasma sprayed and sealed coatings consisted mainly of t′ phase with a very small amount of monoclinic phase (m phase) in the plasma sprayed coatings. It was also found that the small amounts of m and cubic phases (c phase) present in the sealed coatings were dependent on laser processing specific energies (specific energy is equal to laser power/traverse speed x beam diameter). It was also found that rhombohedral (r) phase formed after laser sealing of coatings at higher specific energies. A direct relationship between c/a ratio of transformable tetragonal phase (t phase) produced by thermal treatment of sealed coatings and nontransformable tetragonal phase (t′ phase) and the amount of Yttria was obtained. A new equation was derived, which describes the relationship between Yttria concentration and the c/a ratio of tetragonal phases (t or t′).     

Wear resistance of reactive plasma sprayed and laser remelted TiB2-TiC0.3N0.7 based composite coatings against medium carbon steel

Wear resistance of reactive plasma sprayed TiB₂-TiC_0.3N_0.7 based composite coatings and the as-sprayed coating with laser surface treatment was investigated using plate-on-plate tests. Wear tests were performed at different normal loads and sliding speeds under dry sliding conditions in air. The surface morphologies of counterparts against as-sprayed and laser remelted coatings were investigated. The microstructure and chemical composition of wear debris and coatings were studied using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), respectively. The results show that the wear resistance of the laser remelted coating is improved significantly due to their increased microhardness and reduced flaws. The primary wear mechanism of the remelted coating is oxidation wear and its minor wear mechanisms are grain abrasion and fatigue failure during the course of wear test. In contrast, the primary wear mechanism of the as-sprayed coating is grain abrasion at the low sliding speed (370 rpm) and fatigue failure at the high sliding speed (549 rpm). The oxidation wear mechanism is a minor contributor for the as-sprayed coating.     

双反射镜式光电经纬仪测角误差的分析(轴系部分)

双反射镜式光电经纬仪由于采用了反射镜跟踪头,轴系误差对测角精度的影响不同于典型光电经纬仪。本文从建立经纬仪三维直角坐标系入手,建立了该类型经纬仪轴系误差引起测角误差的数学模型,为精度分析和误差修正提供了依据。     

精度与程度的逻辑或近似算子的性质

本文目的是探讨精度与程度的复合,探索新的粗糙集拓展模型.从精度与程度的逻辑或运算出发,定义了精度与程度的逻辑或粗糙集模型.在该模型中,通过变精度近似与程度近似的转化公式,研究了精度与程度的逻辑或近似算子,并得到了该近似算子的幂作用等性质.用精度与程度的逻辑或粗糙集模型统一了变精度粗糙集模型、程度粗糙集模型和经典粗糙集模型,并在这些粗糙集模型中得到了近似算子幂作用的相应性质.     

Extension of the range of resonator scanning spectrometer into submillimeter band and some perspectives of its further developments

Extension of the working frequency of modern resonator spectrometers into submillimeter wave range is described. Experimental record of atmospheric absorption spectrum covering 45-370 GHz range is demonstrated for the first time, and measured water vapor J′_{ka′, kc′}-J_{ka, kc} = 5_1,5-4_2,2 at 325 GHz line parameters are presented. For the first time pressure lineshift for the 325-GHz water vapor line is measured. Further extension of working range is discussed. New estimations of physical limits of time needed for measurements of absorption in the whole Backward Wave Oscillator (BWO) range are given for phase continuous synthesizer regime. Basic schemes of fast broadband continuous phase synthesized sources are discussed. Verification of the previous measurements of water vapor 3_1,3-2_2,0 at 183 GHz line parameters is presented. Comparisons with ringdown resonator spectrometers are given.