Determination of chlorine ions in raw milk by pulsed amperometric detection in a flow injection system

Chloride ion concentration in milk was determined by pulsed amperometric detection in a flow injection system. Results showed that the Au electrode lost 3 electrons at 1.10 V and formed chloroaurate ions (AuCl₄^?) by combining with chloride ions, after which AuCl₄^? was partly reduced to Au at 0.6 V. Based on the electrochemical process, a triple waveform with detection potential of 1.15 V, detection time of 150 ms, oxidation potential of 1.4 V, oxidation time of 550 ms, reduction potential of 0 V, and reduction time of 400 ms was applied to the Au electrode for detecting chloride ion concentration in milk. The approach is rapid and automatic and features a detection limit of 0.005 g/L. The relative standard deviation obtained by 60 repetitive injections reached 1.48% at 2 g/L of NaCl. The method developed using the Au electrode without modification was used to analyze the chloride ion concentration in raw milk without preprocessing. The method showed good agreement with potentiometric titration.     

碳纳米管表面基团对Bi基催化剂在乙炔氢氯化反应中催化性能的影响

以多壁碳纳米管(MWCNTs)、羟基碳纳米管(MWCNTs-OH)、羧基碳纳米管(MWCNTsCOOH)为催化剂载体,采用等体积浸渍法制备负载型Bi基催化剂,在固定床反应器中评价催化剂在乙炔氢氯化反应中的性能。结果表明,以MWCNTs-OH为载体的Bi基催化剂催化性能最优,乙炔转化率最高52%。BET、FT-IR、XRD、XPS、EDS、TG、TEM和H_2-TPR表征表明,碳纳米管表面基团,尤其是羟基,可以提高活性组分的分散度、抑制催化剂表面积炭生成和减少Bi物种流失。     

Design of data feature-driven 1D/2D convolutional neural networks classifier for recycling black plastic wastes through laser spectroscopy

In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes.     

表面活性剂对电解锌粉形貌的影响

研究氯化铵体系电解制备超细锌粉时,三种典型的表面活性剂对槽电压,锌粉沉积状态和锌粉颗粒大小和形态的影响.结果表明,在锌离子浓度为32g/L.电解液温度为60℃时,非离子表面活性剂吐温-80可以使锌粉颗粒均匀分散,表面活性剂的加入对槽电压影响不大.     

西南稀土矿黑色风化矿泥中铅的回收

西南稀土矿黑色风化矿泥含稀土、铅、锰等，其中铅主要以PbO的形式存在。用热的盐酸溶液浸取稀土的同时，铅也转化为PbCl2进入溶液。利用氯化铅在冷、热水中溶解度相差很大的原理，冷却稀土母液即可回收铅。在试验确定的较佳的浸出条件和适当的冷却温度及时间下，铅的回收率在41%，用热水将浸渣洗涤1次，铅回收率可增加15个百分点。     

离心萃取器在镍钴分离中的应用Ⅱ．用于半工业试验

本文报道３０台φ７０ｍｍ玻璃钢离心萃取器回路在金川有色金属公司半工业试验现场的试验结果。钴的单级萃取级效率＞９６％，反萃取级效率＞９４％。萃取回路连续运行１７４ｈ．处理一次合金与铜渣联合氧气浸出液３．５ｍ￣３。得到三个合格产品液：１￣＃电解镍的电解液，ＣｏＣｌ＿２溶液，Ｃｏ＞１２０ｇ／Ｌ，Ｃｏ／Ｎｉ＞１００００和ＦｅＣｌ＿３产品液，Ｆｅ＞６０ｇ／Ｌ，Ｆｅ／Ｎｉ＞１００００。     

采用离心萃取器萃取净化氯化浸出镍溶液

本研究了氯化浸出含镍物料所得的含钴铁量的高的镍溶液的净化和钴铁回收工艺，采用Ｎ２３５－异辛醇－煤油萃取体系在离心萃取器中分离镍与钴，铜，铁，锌，用离子交换除铅，用活性碳除有机物，得到可用于生产１号标准电镍的氯化镍溶液以及含Ｃｏ大于１００ｇ／Ｌ，Ｃｏ／Ｎｉ大于４０００的氯化钴溶液和含Ｆｅ大于２５ｇ／Ｌ，Ｆｅ／Ｎｉ大于１０００的氯化铁溶液，镍，钴回收率分别大于９９％和９７％。     

氯氧镁水泥喷射混凝土研究

对白云石控温煅烧、氯氧镁水泥反应机理、微观结构、抗水性等方面进行了分析研究，并进行了该水泥喷射混凝土的现场试验。试验表明，氯氧镁水泥喷射混凝土强度高、回弹率低（５．２８％）、粉尘小（１７ｍｇ／ｍ３）。经初步核算，氯氧镁水泥成本只相当于普通水泥成本的８０％。因此，将氯氧镁水泥用于喷射混凝土有着广阔的应用前景和显著的经济效益。     

氯化铵溶液中还原浸出海洋锰结核

采用亚硫酸钠作还原剂对氯化铵溶液中海洋锰结核的浸出行为进行研究，探讨Ｎａ２ＳＯ３加入量、ＮＨ４Ｃｌ浓度及初始ｐＨ值、浸出温度和时间等对锰结核中铜、镍、钴、锰、铁浸出率的影响。结果表明５．０ｍｏｌ／ＬＮＨ４Ｃｌ溶液中，初始ｐＨ值约５．０及８０℃、１８０ｍｉｎ，锰结核与Ｎａ２ＳＯ３等量加入时，铜、镍、钴、锰的浸出率分别为８８．５６％、９６．１４％、７８．５７％、３５．２％，铁几乎未被浸出。而在同样的条件下，控制浸出过程的ｐＨ值４．０左右，１２０ｍｉｎ后铜、镍、钴、锰、铁的浸出率分别为９０．２１％、９８．８０％、９１．４３％、９８．１１％、２０．１３％。     

酸浸高岭土制备PAC时连续搅拌反应器容积计算

酸浸反应器是高岭土制备聚合氯化铝(PAC)的重要设备。基于连续搅拌反应器具有操作简便、产品质量稳定和环境清洁等优点,文章研究了高岭土酸浸连续搅拌反应器容积的计算方法。在相同条件下,采用连续搅拌反应器较为经济。