Angiotensin I‐converting enzyme inhibitory and Ca‐binding activities of peptides prepared from tuna cooking juice and spleen proteases

Tuna cooking juice is a by‐product from the tuna canning industry. In this study, tuna cooking juice was hydrolysed by proteases extracted from the spleen. Tuna cooking juice showed the highest ACE inhibitory and Ca‐binding activities after hydrolysis for 270 and 180 min, respectively. The hydrolysate was further fractionated by ultrafiltration. The permeate exhibited highest ACE inhibitory and Ca‐binding activities when passed through 1 and 5 kDa cut‐off membranes, respectively. Gel filtration chromatography was used to determine the MW of bioactive peptides that exhibited highest ACE inhibitory and Ca‐binding activities. Those peptides that exhibited highest ACE inhibitory and Ca‐binding activities were the MW range of 238–829 Da and 1355–1880 Da, respectively. These results suggest that the tuna cooking juice and the spleen protease extract are a potential source of bioactive peptides that can be utilised as bioactive ingredients in functional food and nutraceuticals.     

铜密闭鼓风炉生产效益的回归分析

通过铜密闭鼓风炉生产过程中关键指标的回归分析,寻找降低消耗、增加产出、提高经济效益的有效途径     

A kinetic model for the acid-oxygen pressure leaching of Ni–Cu matte

A semi-empirical mathematical model for the acid-oxygen pressure leaching of Ni–Cu matte is presented, based on data from batch leaching experiments. The primary controlling factor in the leaching process is found to be galvanic inhibition of the more highly oxidized copper and nickel sulfide species by less oxidized species, particularly Ni alloy and Ni₃S₂. The leaching rate of many species is greatly reduced by the presence of one or both of these phases, and others will not commence leaching until neither is present. The mathematical model is based on first-order chemical reaction controlled rate expressions, as the reactions occurring are electrochemical in nature. Mass transfer effects are included only empirically. Some possibly diffusion-related phenomena are noted, although the model is not extended to incorporate these effects on a fundamental level. The model is verified and extended by the inclusion of several different factors that were tested experimentally. The effects of variations in O₂ flow rate and partial pressure, initial particle size, reaction pulp density and initial acid concentration were all studied, and included in the model. Variations in O₂ flow rate and partial pressure are found to affect the reaction rates via the dissolved oxygen concentration in the solution phase.     

基于核偏最小二乘法的动态预测模型在铜转炉吹炼中的应用

为实现铜转炉吹炼过程中的关键操作参数的准确预测,构造一种基于核偏最小二乘法的动态预测模型,并提出一种适用于动态建模的在线式异常样本剔除方法。该动态预测模型使用滑动窗方法不断更新建模数据,再利用核偏最小二乘法对动态模型的参数进行辨识,最后根据反馈的前次计算误差对本次预测值进行修正。仿真研究结果表明：该动态预估模型具有较好的泛化能力和较强的鲁棒性,并具有较好预测精度（风量预测的相对均方根误差小于10%,氧量预测的相对均方根误差小于19%）。目前,该预测模型被用于某转炉的吹炼辅助决策系统中。     

闪速吹炼炉反应塔内颗粒的反应行为

为深入了解闪速吹炼炉反应塔内颗粒的反应行为变化,通过在不同位置取样,以及对试样进行XRD、XRF、SEM-EDS等分析,观察冰铜粒子在反应塔中的物理化学变化过程,解析冰铜在反应塔中发生着火、氧化脱硫、碰撞聚并、造渣、造铜等变化的规律,了解反应塔产物的特点及烟尘的生成条件。     

基于射频拉远的软件无线电接收机设计

射频拉远是一种新型的分布式网络覆盖模式。其基本思想是将基带部分集中处理,而射频模块则采用单模光纤拉到远端射频单元,从而节省了大量机房,便于管理,维护,同时拓展了网络覆盖面积。该文结合当今数字处理器件的实际水平,给出了基于宽带中频采样方式的接收机结构设计方案,并仿真验证了其可实现性。     

人源血管紧张素转化酶-N结构域基因片段在毕赤酵母中的表达

利用RT-PCR方法从食管癌细胞TE-1中反转出cDNA,PCR扩增得到血管紧张素转化酶N结构域(ACE-N)基因片段,构建pPIC9K-ACE-N表达载体,转化毕赤酵母GSll5,阳性克隆再次电转,并从转化菌株中筛选出多拷贝转化子进行表达.经Ni2+亲和层析柱对表达的蛋白进行纯化,获得的目的蛋白表达量为0.11 g/L,其纯度大于99％.为今后选择性抑制血管紧张素转化酶两个同源结构域的体外研究奠定基础.     

基于数据挖掘的铜转炉渣产出量预报

为实现铜转炉渣产出量的及时准确预报,提出应用数据挖掘技术从现场积累的大量生产数据中发掘相关规律.首先应用线性回归技术建立了仅考虑主要影响因素(铜锍含铁量)的粗略预报模型,而后,应用神经网络技术建立了考虑到多个次要影响因素的误差补偿模型,从而改进预报效果.利用实际生产数据对模型进行了仿真测试,仿真结果表明,模型预报效果良好.     

Intelligent prediction model of matte grade in copper flash smelting process

Due to the importance of detecting the matte grade in the copper flash smelting process, the mechanism model was established according to the multi-phase and multi-component mathematic model. Meanwhile this procedure was a complicated production process with characteristics of large time delay, nonlinearity and so on. A fuzzy neural network model was set up through a great deal of production data. Besides a novel constrained gradient descent algorithm used to update the parameters was put forward to improve the parameters learning efficiency. Ultimately the self-adaptive combination technology was adopted to paralleled integrate two models in order to obtain the prediction model of the matte grade. Industrial data validation shows that the intelligently integrated model is more precise than a single model. It can not only predict the matte grade exactly but also provide optimal control of the copper flash smelting process with potent guidance.     

图像处理系统在网上阅卷中的作用

该文讨论了图像处理系统在网上阅卷中的作用,对图像处理系统中图像灰度化,二值化,去除噪声,图像分割等关键步骤进行了分析。灰度化过程中采用彩色模型转换的方法得到灰度图,二值化过程中采用阈值方法得到二值图像,去除噪声采用中值滤波方法,大大加快了图像处理速度,减少了运算时间,并采用MATLAB编程实现了图像分割。