锌阳极泥制取碳酸锰的研究

以电解锌产生的阳极泥为原料，用≤０．２４６ｍｍ褐煤粉作还原剂，过量５０％，焙烧温度７５０℃，时间８ｈ，此时９０％以上的四价锰还原为二价锰，还原后的焙烧粉经２．０４ｍｏｌ／Ｌ硫酸浸出，浸出液用硫化钠除重金属后用碳酸氢铵进行复分解反应，制得优质的工业碳酸锰，浸锰后的铅、银渣、配入硫化铅精矿后进行火法熔炼，制成粗铅（含银）。     

Production of high-purity molybdenum compounds from a Cu–Mo acid-washed liquor using solvent extraction. Part 2: Pilot and plant operations

Laboratory studies on the recovery of molybdenum from acid wash liquor, reported in Part 1 of this series of papers, identified the optimum process conditions for the production of high purity molybdenum trioxide and calcium molybdate. Pilot and plant scale operations were conducted as a result of the design developed during our laboratory studies.Molybdenum was selectively recovered from a wash liquor containing 10 g/L Mo via a 2-stage extraction using 10% v/v Alamine diluted in Anysol 150 diluent as extractant. The use of 10% v/v isodecanol (IDA) was found to enhance the extraction of molybdate from the wash liquor. The organic extractant liquor had to be scrubbed with water to remove the ammonium sulphate crud formed when ammonium hydroxide solution (20% w/v) was used to strip the molybdate from the loaded organic. The pilot scale study (0.2 m³/day) and plant operation (30 m³/day) were able to be continuously operated to recover 99% Mo from the wash liquor, from which high purity MoO₃ and CaMoO₄ of >99.9% purity could be recovered.     

Assessment of Different Irrigation Management Models in Vietnam

An assessment of three institutional models for irrigation management in Vietnam is presented. The first model is a joint management by a state agency and farmer organization; the second is a shared management by a quasi-state and farmer organization; and the third is management solely by a farmer organization. The first model is a conventional management system, whereas the latter two models have recently been introduced in a limited number of projects as a result of the government policy on reform in the irrigation sector. Three study sites are identified to represent three management models. Apart from the institutional framework and selected management functions, water distribution and agricultural productivity are evaluated and compared. Results indicate the better performance of management models with increased involvement of farmers in the decision-making process. It is recommended that the hydraulic boundaries should be taken into consideration in reforming management systems for irrigation projects.     

Zero-Phase Filtering for Lightning Impulse Evaluation: A K-factor Filter for the Revision of IEC60060-1 and -2

The next revision of the international standard for high-voltage measurement techniques, IEC 60060-1, has been planned to include a new method for evaluating the parameters associated with lightning impulse voltages. This would be a significant improvement on the loosely defined existing method which is, in part, reliant on operator judgment and would ensure that a single approach is adopted worldwide to determine peak voltage, front, and tail times, realizing standardization in measured parameters across all laboratories. Central to the proposed method is the use of a K-factor to attenuate oscillations and overshoots that can occur with practical generation of impulse voltages for testing on high-voltage equipment. It is proposed that a digital filter that matches the K-factor gain characteristic be implemented and used for this purpose. To date, causal filter designs have been implemented and assessed. This paper is concerned with the potential application of a noncausal digital filter design to emulate the K-factor. The approach has several advantages; the resulting design is only second order, it can be designed without using optimization algorithms, it is a zero-phase design and it matches the K-factor almost perfectly. Parameter estimation using waveforms from the IEC 61083-2 test data generator and experimental impulse voltages has been undertaken and obtained results show that the zero-phase filter is the ideal digital representation of the proposed K-factor. The effect of evaluating parameters by the proposed method is compared to mean-curve fitting and the challenge of effective front-time evaluation is discussed.     

Diimide reduction of cis-1,4-polyisoprene with p-toluenesulphonylhydrazide

The hydrogenation of cis-1,4-polyisoprene with diimide generated in situ from p-toluenesulphonylhydrazide (TSH), was investigated under various conditions. In aromatic solvents at 100–140°C, the rate of hydrogenation was increased with increase in concentration of polyisoprene and of TSH. Part of the polymer was depolymerized and cyclized during the reaction. Increasing the hydrogenation tended to decrease the rate of sulphur vulcanization, of the compounded rubber and the physical properties of vulcanizates were poor. The reaction of polyisoprene rubber with TSH, was also carried out in a solid state at 140°C for 20–60 min. It was found that by using a large amount of TSH hydrogenation and cyclization of rubber occurred. The quantity of TSH used as a blowing agent, for rubber in the manufacture of sponge rubber, i.e. 5–10 phr, did not cause hydrogenation.     

Microwave plasma-assisted etching of diamond

Experimental results are presented for the microwave plasma-assisted dry etching of ultrananocrystalline (UNCD), polycrystalline and single crystal diamond materials. A high-rate and anisotropic etching process is developed using a 2.45 GHz microwave plasma reactor. The plasma discharge in this system measures 25 cm in diameter and is located inside a 30 cm diameter microwave cavity applicator. The system is an electron cyclotron resonance (ECR) plasma source operating at pressures of 1–100 mTorr. The process chemistries include mixtures of oxygen, sulphur hexafluoride, and argon. Anisotropic etching profiles have been demonstrated and the measured etching rates range from 4–26 μm/h.     

Towards a Dual-Tip STM Application in Mesoscopic Electron Transport

A new design for a dual-tip scanning tunneling microscope (STM) is presented. The design is a variation on the mechanically controllable break-junction with two electron beam-induced deposition nano-tips. The new design enables one to scan surfaces simultaneously with two probes having a nano-gap separation. By collecting the lateral current flowing between the tips, the transconductance map can then be compared with the STM images for local characterizations of the electron transport. Since the lateral beam carries the property of the density of states of the surface at momentum space, the dispersion of the electronic structure should give an orientation and position dependence of the local transconductance current. In addition, the reduced terminal separation, on the order of the characteristic mesoscopic length scales, is likely to be sensitive to a variety of typically observed interactions and interference effects.     

地震信息约束的三维建模技术及其在松辽盆地古龙页岩油地质工程一体化中的应用

以三维地质建模为基础的地质工程一体化已经成为非常规油气勘探开发的关键技术.由于松辽盆地古龙页岩油的钻井资料少、数据冗杂,亟需开展基于地震信息约束的三维地质建模技术研究,来满足页岩油藏丛式水平井平台勘探开发需求.根据古龙页岩油为代表的陆相页岩油建模的独特性,以工厂化、集约化的布井思路为指导,充分利用钻井、测井和地震预测数...     

基于TPS 复合结构毁伤的等效仿真方法

基于破片存速对某高空高速飞行器热防护结构的影响,提出一种用单一材料结构替代热防护系统(thermal protection system,TPS)复合结构毁伤的等效仿真方法.15 mmTPS热防护复合结构板经计算可等效为4.3 mm铝合金板,经试验验证误差仅为5.6％,吻合度较高,破片穿透板后,TPS复合材料层形成的破孔周围有明显扩孔现象.将试验与仿真结果对比发现:靶板正面与背面破孔直径误差分别为2.9％和2％,铝合金和TPS复合结构极限速度误差分别为2.3％和1.4％.结果表明,该方法对热防护复合结构的设计及优化具有一定参考价值.     

日本清酒入门(二)

简要介绍日本清酒的生产方法,包括酒的知识、精米、蒸米、制曲、酵母、分析、勾兑等。