聚氯乙烯塑料中多种邻苯二甲酸酯类增塑剂的同时测定

为了在线监控聚氯乙烯塑料中增塑剂的含量,利用傅立叶变换红外光谱法-ATR技术测定样品的红外光谱,采用偏最小二乘法对所测红外光谱进行分析,建立了一种无损快速分析方法,定量地测定聚氯乙烯塑料中多种邻苯二甲酸酯类增塑剂的含量。该方法测量精密度的变异系数小于6%,测量准确度的变异系数小于3%。该方法不受基体的干扰,简单快速,适合于流水线的质量控制。     

基于改进多核学习的语音情感识别算法

提出一种基于改进多核学习的语音情感识别算法.算法以高斯径向基核函数为基准,通过采样不同的样本,采用不同的评价标准并获得不同的参数,来提高分类性能.此外,通过引入多核技术,将得到的高斯核函数构建多核学习的基核,并通过利用松弛因子构建的软间隔多核学习的目标函数改善了学习效率.对比仿真实验结果表明,本文提出的基于多核学习语音情感识别算法有效提高了语音情感识别性能.     

YL-1OO型自动加药装置在乙烯循环水场的应用

介绍了国产YL-100型自动加药装置功能及其在中国石化茂名石化乙烯工业公司乙烯循环水场的应用情况,结果表明其运行平稳,总磷测试数据可靠,可达到循环水自动加药控制的目的。     

甲苯二异氰酸酯（TDI）的市场开拓

甲苯二异氰酸酯(TDI)是合成聚氨酯高聚物的主要原料之一,本文简要地论述了该产品的国内外发展与现状,从当前国内市场出发,认为开发面广,量大和价廉的新制品是我国TDI市场的开拓方向和当务之急,并提出了5项具体的开发项目,以有助于该产品的迅速发展。     

声波清灰在水泥库防粘附上的应用研究

正0前言水泥行业成品库结块问题由来已久,以前的清理方式是在结块非常严重后,由人工来完成。但是伴随健康、环保、安全方面的要求越来越严格,如何能够做到无人显得尤为重要。主流的机械清库设备清理需要在水泥库停用后进行操作,而且清理周期动辄三四个月,影响较大,另外清理到最后还是     

明胶和胶囊生产干燥新工艺的研究

本文介绍了氯化锂液体除湿的工作原 理,并深入分析了其除湿工艺、主要特点和在 明胶与胶囊干燥方面的研究和应用。     

UHMWPE混炼接枝马来酸酐研究

讨论了超高相对分子质量聚乙烯(UHMWPE)混炼接枝马来酸酐(MAH)过程中，单体MAH用量、引发剂DCP用量、交联抑制剂己内酰胺(CAILA)用量、流动改性剂硬脂酸钙(CaSt2)用量及混炼温度、时间等工艺条件对UHMWPE接枝率和凝胶含量的影响。用红外光谱表征了接枝物的存在。并用滴定分析法和重量分析法测定了接枝物UHMWPE～g～MAH的接枝率和凝胶含量。实验表明，MAH用量为5份、DCP为0．15份、CALA为0．1份、CaSt2为1份时。混炼温度175∽180℃。混炼时间14min时，可得到接枝率0．75％、凝胶含量1．48%的UHMWPE接枝物。     

基于动态特性的D-LTSV语音端点检测方法

端点检测是语音信号处理的一个关键环节。为提高语音在低性噪比以及非平稳噪声环境下的端点检测性能,在长时信号变化特征(LTSV)的基础上提出一种新的D-LTSV语音端点检测方法。采用Bartlett-Welch方法估计语音谱,分析语音谱在长时域上的熵,利用倒谱的动态特性分析方法提取连续帧熵值的动态变化特征。实验结果表明,D-LTSV综合考虑了语音的非平稳性和帧间非平稳性的动态变化情况,具有比LTSV更好的分辨能力,特别是在低性噪比和非平稳噪声的环境下,D-LTSV的分辨能力提升了50.77%,能够准确地进行端点检测,具有更强的鲁棒性。     

Preparation and characterization of a PMMA/Ce(OH)3, Pr2O3/graphite nanosheet composite

An easy process for the synthesis of poly(methyl methacrylate)/Ce(OH)₃, Pr₂O₃/graphite nanosheet (PMMA/Ce(OH)₃, Pr₂O₃/NanoG) composite was developed. Graphite nanosheets (NanoG) were prepared by treating the expanded graphite with sonication in aqueous alcohol solution. The PMMA/Ce(OH)₃, Pr₂O₃/NanoG composites were prepared via in situ polymerization of MMA monomer in the presence of graphite nanosheets and Ce(OH)₃, Pr₂O₃ through reverse micelle template, in which the methyl methacrylate was designated as the oily phase. The composites were then dispersed with chloroform and coated on glass slides to form films. Scanning and transmission electron microscopy were used to characterize the structure and dispersion of the graphite nanosheets and the composites. The results showed that the high-aspect-ratio structure of the nanosheets played an important role in forming a conducting network in the PMMA matrix. From thermogravimetric analysis, the introduction of graphite nanosheets and inorganic nanopartices exhibited a beneficial effect on the thermal stability of PMMA.     

Exothermic effect in the process of electron‐beam curing of epoxy resins

Temperature measurements have been performed in the process of electron‐beam curing of EB‐I and EB‐II epoxy resin systems. The influence of initiator content, resin type, and dose rate on the temperature of the systems was studied. Transverse and longitudinal temperatures of samples in the glass vessel were also analyzed. The nature of temperature curves varied with the different epoxy resin systems in the steel mold, but did not change with different contents of the initiator. At the same time, the heat had no effect on the gel fraction of epoxy resin systems. The temperature curve was greatly affected by the dose rate, and its peak value, peak width, and plateau value also increased with it. The transverse temperature of EB‐II glass vessel samples increased as the radiation dose increased and, in the same sample, the temperature reduced as the distance between the radiation center and the test point increased. The longitudinal temperature of EB‐I and EB‐II resin systems in a glass vessel decreased as the radiation depth increased. As the radiation dose increased, the temperature of the EB‐I resin system increased simultaneously, while that of the EB‐II resin system initially increased and then kept constant when the dose reached a certain value. The temperatures of these two resin systems decreased rapidly when the radiation process stopped. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2217–2222, 2004