开流改为圈流水泥联合粉磨系统的提产措施

贵州科特林水泥有限公司2号线原为CLF辊压机＋V选粉机和中3．2m×13m开流磨组成水泥联合粉磨系统,生产P·C32．5水泥时台时产量为65～70t／h。为进一步提高产能,使用K2000选粉机将开流磨改成圈流磨。于2009年7月技改工程结束,选粉机投入使用。技改后台时产量达90t／h,但运行一段时间后产量开始下降,经采取一系列措施,目前系统产量稳定在90～95t／h。     

Copper and brass aged at open circuit potential in slightly alkaline solutions

Surface oxide films were grown on 99.99% copper and brass (copper–zinc alloy, Cu77Zn21Al2) in 0.1 mol L⁻¹ borax solution at open circuit potential and were characterized using various experimental techniques. The composition of the passive films formed in situ on the different materials was studied using differential reflectance spectroscopy. The thickness of the oxide layers on copper and brass was compared by chronopotentiometric curves and potentiodynamic reductions. The electrical properties of each oxide were analyzed by means of electrochemical impedance spectroscopy. Their influence on the oxygen reduction reaction was also investigated using voltammetry hydrodynamic tools such as the rotating disk electrode. The results show that the incorporation of Zn to Cu in brass changes the composition and the thickness of the surface film. The films grown on brass tend to be thicker but less resistive and Zn compounds incorporate to the film. This is supported by results from reflectance and impedance spectroscopy. The kinetics of oxygen reduction is strongly inhibited on oxidized electrodes, particularly in the case of brass. The global number of exchanged electrons remains close to four and seems to be independent of the presence of surface oxides.     

Highly selective partial hydrogenation of 1,3-butadiene on platinized-platinum electrode in ethylenediamine at open circuit

It was found that platinized-platinum ethylenediamine (EDA) is extremely selective (ca 93%) for the partial hydrogenation of 1,3-butadiene, given three isomeric butenes in a ratio of 1-butene: trans-2-butene: cis-2-butene = 13.2:2.5:1. Such a highly selective partial hydrogenation would be due to a specific adsorption of EDA on pt-Pt giving rise to the replacement of the adsorbed butenes which were formed from the partial hydrogenation of 1,3-butadiene.     

Manganese films electrodeposited at different potentials and temperatures in ionic liquid and their application as electrode materials for supercapacitors

Electrodeposition of manganese (Mn) in butylmethylpyrrolidinium bis(trifluoromethylsulfony)imide (BMP-NTf₂) ionic liquid is demonstrated in this study. Crystal structures and surface morphologies of the Mn films deposited at various potentials (from −1.8 V to −2.2 V) and temperatures (from 50 °C to 110 °C) were examined with an X-ray diffractometer (XRD) and a scanning electron microscope (SEM), respectively. Experimental results indicate that the deposited Mn films were amorphous in nature; however, their morphologies strongly depended on the deposition conditions. After being anodized in Na₂SO₄ solution, the deposited Mn was transformed to Mn oxide. Electrochemical properties of the Mn oxides were evaluated using cyclic voltammetry (CV). It was confirmed that the different Mn deposition conditions caused the variations in pseudocapacitive performance of the oxide electrodes. The oxide (∼0.1 mg) anodized from the Mn deposited at −1.8 V and 50 °C had the highest specific capacitance of 402 F/g measured at a CV scan rate of 5 mV/s. Its capacitance retained ratio after 500 CV testing cycles was as high as 94%.     

Comparison of pH 6 potentials, alkaline potentials and initial open circuit voltages of electrolytic MnO2

The alkaline battery industry typically reports three electrolytic MnO₂ (EMD) potentials: alkaline potentials, pH 6 potentials, and initial open circuit voltages (IOCV). These measurements differ with the electrolyte, the reference electrode, and the cathode composition. Despite such physical differences, theoretical relationships exist between the electrolytic potentials that are verifiable by experiment. The calculated difference (alkaline potential – pH 6 potential) is 0.785 V, which compares favourably with the experimental value of 0.795 ± 0.003 V. Another difference (alkaline potential – IOCV) depends on carbon-induced EMD reduction, which varies with EMD type and graphite:EMD ratio. After determining the carbon effect experimentally and graphically estimating [ZnO₂ ^2–], (alkaline potential – IOCV) was calculated as –0.045 V. This is roughly 60 mV from the experimental value of +0.017 V. Our analysis shows that when the differences in electrolyte and cathode compositions, and reference electrodes, are accounted for, the three EMD potentials are equivalent.     

Label-Free Detection of Protein interactions with peptide aptamers by open circuit potential measurement

Label-free electrical detection of protein interactions has been achieved by direct measurement of variations in open circuit potential (OCP) using an accurate differential voltage measurement. Our model system involves a panel of peptide aptamers that recognise specific protein partners of the cyclin-dependent kinase (CDK) family.Different peptide aptamers immobilized on gold electrodes were used for the detection of human CDK2 and CDK4. The formation of the peptide aptamer recognition layer and the efficiency of its interaction with CDK proteins in yeast cell lysates were characterized by quartz crystal microbalance measurements. The interaction of the peptide aptamers with CDK proteins was successfully detected by direct OCP measurements. The OCP dependence on the pH of the measurement buffer confirms that the effects observed are due to the change in charge upon protein interaction. Variations in charge transfer resistance and in protein/double-layer capacitance were investigated by means of electrochemical impedance spectroscopy with charged redox markers in solution.The present work shows that electrical detection of protein interactions can be achieved by direct measurement of OCP variations using suitable differential voltage instrumentation. The results indicate that label-free detection of protein interactions is possible with potentiometric transducers such as field-effect transistors.     

Effect of gelling on the open circuit potential against time transients of Pb/PbSO4 electrodes at various states of charge

The technique of open-circuit potential relaxation from a prior prepolarized state has been employed to study the kinetics of the Pb/PbSO₄ electrode in 4.81 m sulphuric acid. The significant features governing the relaxation have been quantitatively analysed to obtain a correlation between state-of-charge of the electrode and its potential-recovery time constant. The effect of immobilizing the electrolyte has also been included due to its relevance in making sealed maintenance-free batteries. The study provides a method for estimating the variation of exchange current density of the Pb/ PbSO₄ and hydrogen evolution reactions at various states-of-charge with and without added gelling agents.This paper is dedicated to the memory of the late Professor S. Sathyanarayana.     

Mercury-mercurous propionate electrode: standard potentials at different temperatures and related thermodynamic quantities

The standard molal potentials E°_m of the Hg/Hg₂(OPr)₂, OPr⁻ electrode at 15°, 20°, 25°, 30° and 35° C have been determined. The E°_m values obtained are 0.5114, 0.5072, 0.5031, 0.4988 and 0.4942 V respectively, which can be fitted to the equation Edg_m/V = 0.5031 −8.56 × 10⁻⁴ (itt/°C − 25)−3.0588 × 10⁻⁶ (t/ °C -25)². The changes in standard free energy, entropy and enthalpy for the cell reaction have been calculated.     

An investigation of a potential step at a channel electrode

The present paper deals with a theoretical investigation of a potential step at a channel electrode. The study consists in the numerical solution of the partial differential equations relevant to the transient mass balance in the vicinity of the electrode, taking into account the convective term. Although such an equation has been investigated previously for both heat and mass transfer, we present the results obtained with the help of two packages relying upon either the numerical method of lines (DSS/2) or a derived Gear technique (LSODA). Results of the simulation — concentration profile and wall concentration gradient — are reported and a comparison with previous results is carried out. Both packages used yield very similar current variations which are observed to be in a good agreement with experimental data.     

闭路水泥磨研磨体级配的探讨

1有效装载量研磨体的装载量如何配合才能体现其有效性是,水泥工作者不断研究的课题配合好的装载量被称为。有效装载量有效装载量还可以这样描述当磨机钢,:球装载量近乎于台时产量的2倍时其钢球装载量即,被视为有效装载量换言之有效装载量的目标是使。,水泥磨装载量低于台时产量     

湿法生料磨改联合粉磨开流水泥粉磨系统的实施

天瑞集团水泥有限公司在13前的4000t／d干法水泥技改工程项目中，为控制投资、充分利用现有设备资源，经多方考察论证，最终采用目前国内比较先进的料层粉磨技术和V型选粉机分选技术；并将已停产闲置的3mxl2m湿法生料粉磨系统改造为联合粉磨的开流水泥粉磨系统，走出了一条投资省、见效快的新路子，现作一简要介绍。     

通用循环水冷却器延时关闭控制联动电路设计

目前许多大型仪器的循环冷却水系统,都没有提供相应的自动化延时关闭装置,给工作带来不便。经过分析,将主机供电系统与循环冷却水供电系统进行关联,设计了联动电路,实现了正常关机,循环冷却水系统自动延时20min后关闭。既节约了工作时间,又提高了工作效率。     

Mercury-mercurous propionate electrode: standard potentials at different temperatures and related thermodynamic quantities in dioxan-water media

The standard molal potentials (E°_m/V) of the Hg/Hg₂(OPr)₂, OPr^? electrode at 15, 20, 25, 30 and 35°C have been determined in dioxan-water media. The values of E°_m as a function of the Celsius temperature, t, in different solvent composition may be represented by the following equations:

The related thermodynamic quantities have been calculated. The dependence of the standard potentials at 25°C on the dielectric constant of the media (in the light of the Born equation), the volume fraction (Φ_w) and the mole fraction (N_w) of water (based on Feakins-French relationship) have been examined. The variation of the thermodynamic quantities ΔG°, ΔS° and ΔH° with various parameters associated with solvent media have also been examined. The observations are similar to those reported in our previous work on mercury-mercurous acetate electrode in the same media. ΔC°_p for the cell reaction has been calculated.     

减少开路水泥粉磨系统磨尾熟料颗粒的措施

我厂2台Φ2.4m×13m开路高细磨因开路系统存在严重过粉磨及磨尾水泥成品中含有熟料颗粒等问题,使粉磨系统很难达到优化状态。水泥颗粒在经包装回转筛时能够筛除,不会给施工带来影响,但采用散装水泥时,特别是精确计量水泥量的施工中,常常因水泥中的颗粒,而使设备不能正常运转,影响施工。为此,对我厂开路水泥粉磨系统磨尾颗粒进行了检测并采取了一些改进措施。1磨尾颗粒的检测研究1.1磨尾颗粒的检测方法及结果　　检测时,分别对1号、2号水泥磨磨尾多次瞬时取样,做筛余分析,研究掌握我厂磨尾颗粒的现状。　　每2h为1个检测周期,每…     

Spontaneous polymerization of acetaldehyde to polyacetaldehyde at close to dry-ice temperature

Polyacetaldehyde has been prepared in the liquid and vapor phases without the addition of a catalyst by storing undiluted acetaldehyde in the dark at a temperature of ?68°C. for 3–6 months. When acetaldehyde was stored in an untreated Pyrex flask, 20% high polymer, 55% paraldehyde, and less than 1% metaldehyde were obtained. The polymer was an elastomeric solid with a low to moderate degree of crystallinity and an intrinsic viscosity of 0.63 dl./g. When the sample was stored in a Pyrex flask which had been pretreated with alcoholic potassium hydroxide followed by a water wash, 16–17% high polymer and 6% paraldehyde were obtained. Some polymer formed on the unwetted glass above the liquid. It was slightly elastic, at least moderately crystalline, and had an intrinsic viscosity of 1.6 dl./g. It is suggested that the formation of this polymer was initiated by basic active sites on the Pyrex surface which acted by an anionic mechanism. Also some polymer was formed in the liquid phase. This material was an amorphous, highly viscous oil with an intrinsic viscosity of 0.28 dl./g. It was probably formed by a cationic mechanism. It is also suggested that a relatively small amount of paraldehyde was formed in the alkali-treated flask in the liquid phase due to neutralization of the Brønsted acid sites and possibly some of the Lewis acid sites on the surface of the flask.     

Electrocatalytic hydrogenation processes at controlled potential—2. Charge transfer at a slurry electrode

A theoretical approach has been made to charge transfer processes in a slurry cell with catalyst particles. The processes are described with an equivalent electric circuit. Calculations have been made of the potential of the catalyst as a function of the rate of the different charge transfer processes.Analogous calculations have been made to determine the conditions to measure the catalyst potential accurately with a measuring probe.     

PLC扩展模块在三维电极反应器内电位分布测量中的应用

用PLC扩展模块对三维电极反应器内电位分布进行了研究,分析了相邻点电位差对不同位置去除率的影响,在提高三维电极应用的自动化程度方面做了一些尝试.     

Φ2.2m×7.0m开流水泥磨磨内改造措施

1存在的问题及分析2001年初,我厂采用高细磨技术对Φ2.2m×7.0m开流水泥磨进行改造。运行1年来,产质量有一定的提高但不很理想,产品细度仍然偏高(4.0%左右),且时常有跑粗现象发生,台时产量不高,用户反映施工性能欠佳。在生产过程中表现出运转率不高,一仓经常断衬板螺栓、筛分装置易磨穿。每次打开磨门都发现有不同程度的包球、段现象。为了查找原因,做了筛余曲线见图1。图1改造前磨机筛余曲线由图1可看出:1)如一仓入口处筛余为54.2%,出口处为44.0%,下降不多,其余各仓也与此相似。效率低的原因在于各仓粉磨的有效空间太小。2)在每个隔仓板前…