酸奶用乳酸菌的人工消化耐受性研究

对酸奶尤其益生菌酸奶加工常用的嗜热链球菌、保加利亚乳杆菌、嗜酸乳杆菌和双歧杆菌4支菌种,在人工模拟胃肠消化条件下进行了耐受性研究.结果表明,嗜热链球菌和保加利亚乳杆菌在经过胃肠消化后活菌数几乎消失殆尽,嗜酸乳杆菌和双歧杆菌耐受消化的能力较强.本研究初步证实了嗜酸乳杆菌和双歧杆菌的益生菌功效.     

在线拉曼光谱仪在芳烃装置中的应用及荧光背景处理

介绍了在线拉曼光谱仪在芳烃PX装置的使用情况,并且针对传统的拉曼光谱预处理方法不能很好地解决现场使用中产生的荧光背景干扰问题,提出了基于小波变换的在线拉曼光谱信号预处理方法.试验结果表明:将小波变换应用到拉曼光谱谱图数据预处理中,能够较好地减弱荧光背景干扰,从而提高在线拉曼光谱仪的分析精度和模型稳定性.     

基于 VPR的 FPGA 布局算法的改进

通过在原模拟退火算法中加入回火过程对原算法进行优化,同时,减小内循环次数用于弥补回火导致的布局时间增量。回火过程用于寻找“被遗漏”的最优解。结果表明新算法利于跳出局部最优“陷阱”,进一步搜索最优解,具体体现在改进后的算法不但能够保证布局质量,而且缩减了布局时间,同时,布线时间与电路关键路径延时得到不同程度的改善。     

星地激光通信无波前传感器优化算法仿真分析

在星地激光通信中,大气扰动会降低通信质量,在通信的接收端对大气扰动进行补偿,能提高通信质量。通信中的强闪烁等会出现波前探测器不能探测出波前畸变的情况,需要采用无波前探测器的成像校正技术来实现星地激光通信中大气扰动的补偿。为了实现星地激光通信中大气扰动的实时补偿,对改进遗传、模拟退火和模式逼近法这三种优化控制算法进行了仿真,并从算法的收敛速度、校正效果、稳定性和变形镜操作次数等四个方面进行了比较和分析。仿真结果表明:遗传算法收敛速度慢,但将归一化光强从0.079 5提升到0.99,适合于对静态像差的校正;模式逼近法只需要2次迭代就能将归一化光强从0.079 5提升到0.862,适合于星地激光通信中大气扰动的实时校正。     

EEMD-NNBR模型在降水预测中的应用

为解决降水资源预测复杂的问题,建立了具有物理意义的新预测模型,即利用集合经验模态分解(EEMD)方法,分解降水资源并识别其演变模式,获得各本征模函数(IMF),然后结合最近邻抽样回归模型(NNBR)对数据进行预测分析,汇总相应的计算结果,从而构成了EEMD-NNBR降水预测模型。以无锡市惠山区的降水序列资料为例,采用EEMD-NNBR模型预测降水资源,并与单一的NNBR模型预测值进行对比分析。结果表明,所建模型稳定性较好,能合理预测水资源演变趋势,提高降水资源预测精度,具有一定的应用价值。     

X80钢在鄯善土壤模拟溶液中的腐蚀行为

利用失重法、电化学测试、SEM(扫描电镜)和EDS(能谱分析)等方法,研究X80钢在鄯善土壤模拟溶液中的腐蚀行为。结果表明:X80钢在3个测试点模拟土壤溶液中以全面腐蚀为主,局部位置发生点蚀;其在代号为AN000,AN065和AN016的模拟溶液中浸泡60 d的腐蚀速率分别为0.55,0.4和0.03 mm/a,腐蚀速率依次减小;随着浸泡时间的增加,Ca2+吸附在X80钢表面并形成Ca的产物层,有效地减缓了X80钢在AN016模拟溶液中的腐蚀。在盐含量较高的土壤环境中,富集在钢基表面的结晶盐对钢的腐蚀具有一定的减缓作用。     

Desulfurization of Simulated Oils by Microwave Chemical Methods

Abstract

Microwave technology was introduced for the desulfurization of sulfurous crude oil and the influence of microwave processes on removing benzothiophene sulfur and bi-benzothiophene sulfur in simulated oils was studied in this article. The results manifested that the desulfurization efficiencies of BBPV, formylhydroperoxide and peroxyacetic acid for an oil sample (simulated oil 2) containing bi-benzothiophene were better than for the oil sample (simulated oil 1) containing benzothiophene. When dosages of BBPV increased from 0.5% to 4%, the desulfurizing efficiencies of simulated oil 1 and 2 were raised from 19.8% to 53.7%, and 48.0% to 64.2%, respectively. With the increase of temperature, the reaction order desulfurization of the simulated oils by microwave increased, and the rate of the microwave reaction increased. The desulfurizing efficiency increases along with the temperature in the same time.     

Preliminary Research on Desulfurization of Simulated Diesel Fuel with Peroxotungstate Biquaternary Ammonium Salt/H2O2 System

Abstract

A biquaternary ammonium salt catalyst, chloride-1,4-dibenzyl-diaza-bi-cyclo [2.2.2] octane peroxotungstate (peroxotungstate biquaternary ammonium salt), was prepared, the structure of which was determined through infrared spectrometry, and was applied in desulfurization of simulated diesel fuel. Under the circumstances in which the close ion-pair of biquaternary ammonium cation and peroxotungstate anion was formed, the mechanism of phase transfer catalysis was offered with analyzing experimental process and data. The desulfurization efficiency reached 99.35% when the reaction temperature was 60°C, the reaction time was 20 min, and the molar ratio of peroxotungstate biquaternary ammonium salt to H₂O₂ was 0.015.     

电网行波故障定位装置的优化配置

在研究电网行波故障定位方法的基础上,提出了一种行波故障定位装置的优化配置方法。该方法首先依据配置原则对电网中的变电站配置行波定位装置,然后利用模拟退火算法对初始方案进行优化,将配置过程和优化过程有效结合后提高了初始配置方案的质量,缩小了模拟退火算法的寻优范围,从而提高了求解速度。实际系统的配置分析和仿真结果表明适当的优化配置可以在不影响定位可靠性和准确性的前提下减少定位装置的布点,从而有效节省投资。