The residual zonal flow in tokamak plasmas with a poloidal electric field

In a tokamak plasma with auxiliary heating by cyclotron waves, a poloidal electric field will be produced, and as a consequence influence the residual zonal flow(RZF) level. The poloidal electric field can also be induced through biasing electrodes at the edge region of tokamaks.Numerical evaluation for a large aspect ratio circular cross section tokamak for the electron cyclotron wave heating indicates that the RZF level decreases significantly when the poloidal electric field increases. Qualitatively, the ion cyclotron wave heating is able to increase the RZF level. It is difficult to apply the calculation to the real cyclotron wave heating experiments since we need to know factors such as the plasma profiles, the exact power deposition and the cross section geometry, etc. It is possible to use the cyclotron wave heating to control the zonal flow and then to control the turbulence level in tokamak experiments.     

超声机械法制备纳米二氧化硅及影响因素分析

引言 20世纪,人们发现了纳米粒子具有传统常规颗粒材料所不具备的优良的理化性质和特殊的光、电、磁等特性,从而开始了对纳米粒子的研究,其中包括对纳米粉体粒子基本制备方法的探索[1].纳米粉体粒子的制备方法可以归结为两大类:一类是粉碎法,即将宏观物体逐步细化得到纳米颗粒;另一类是构筑法,即从原子、离子或分子出发,通过成核和长大两个阶段来构筑纳米粒子[2].构筑法制备纳米粉体粒子所用的能量主要为热能和化学能,需要较高的温度,消耗较高能量,后续的除杂工艺较为繁杂,生产过程中还有可能造成环境污染等.而粉碎法制备纳米粉体粒子,设备投资少、能耗低、效率高、生产能力大、生产过程和产品性能易于控制.     

煤矿黏土注浆管路淤堵软化实验与应用

为了解决煤矿黏土注浆管路淤堵问题,开展黏土注浆管路淤堵软化实验和应用研究。在黏土注浆管路淤堵特征剖析的基础上,通过软化剂作用下黏土崩解实验开展相关研究。结果表明:强氧化类的软化剂与黏土试样反应最为激烈,碱性软化剂与黏土试样反应最慢,酸性软化剂与黏土试样反应速度适中。以0.1 mol/L氨基磺酸溶液或0.25 mol/L醋酸溶液作为黏土淤堵软化剂最优。实践证明,采用管路涂抹环氧树脂,重点部位压力监测,淤堵管路浸泡软化剂等手段可以有效防治黏土灌浆管路淤堵问题。     

江西白垩系泥质粉砂岩崩解试验研究

对南昌地区泥质粉砂岩典型出露地段开展现场调研并取样测试其基本物理力学性质,同时进行了静态崩解试验和岩石的耐崩解试验,从能量耗散原理的角度分析了泥质粉砂岩静态崩解过程中吸收的能量向表面能转化的规律。试验结果表明:水和温度—岩的相互作用是加快泥质粉砂岩风化的主要外部营力;泥质粉砂岩的静态崩解由碎块状过渡到粒渣状、泥糊状,可按崩解物形态划分为剧烈崩解、细微崩解和崩解稳定三个阶段,崩解过程中其表面能累计增加量随崩解次数增加而增加,而单次表面能增量趋于减小;耐崩解试验中,泥质粉砂岩耐崩解性指数随循环次数的增大呈负指数关系递减。试验结果对于工程实践中如何抑制红层软岩崩解并保持其完整承载能力、或对其预崩解处理促进其快速崩解达到稳定的颗粒级配状态具有一定的参考价值。     

泥岩孔裂隙分布特征及其对吸水性的影响

基于泥岩样品的扫描电镜测试和液氮等温吸附试验,系统研究煤系泥岩的显微孔裂隙形态特征和分布规律,进而探讨孔裂隙分布特征对其吸水软化崩解性的影响规律。主要研究成果为：① 泥岩孔裂隙类型有粒间孔、层间孔、粒缘收缩孔、气胀孔、溶蚀孔、矿物铸模孔及裂隙等;② 孔裂隙的发育程度及相互间的连通性差,自然状态下,多以隐裂隙的形式存在,肉眼很难辨别;③ 孔裂隙以所含黏土矿物微集聚体间孔隙和构成泥岩骨架的大颗粒间孔隙为主,其中构成泥岩骨架的大颗粒间孔隙体积占泥岩总体积的20%以上;④ 泥岩吸水软化崩解是在宏观结构破坏或扰动的基础上,由微孔裂隙吸附效应引起的,受其物质组成不同的影响,自然吸水率和软化崩解机理存在明显差异。     

Mechanical sludge disintegration for the production of carbon source for biological nutrient removal

The primary driver for a successful biological nutrient removal is the availability of suitable carbon source, mainly in the form of volatile fatty acids (VFA). Several methods have been examined to increase the amount of VFAs in wastewater. This study investigates the mechanism of mechanical disintegration of thickened surplus activated sludge by a deflaker technology for the production of organic matter. This equipment was able to increase the soluble carbon in terms of VFA and soluble chemical oxygen demand (SCOD) with the maximum concentration to be around 850 and 6530 mgl(-1), for VFA and SCOD, respectively. The particle size was reduced from 65.5 to 9.3 microm after 15 min of disintegration with the simultaneous release of proteins (1550 mgl(-1)) and carbohydrates (307 mgl(-1)) indicating floc disruption and breakage. High performance size exclusion chromatography investigated the disintegrated sludge and confirmed that the deflaker was able to destroy the flocs releasing polymeric substances that are typically found outside of cells. When long disintegration times were applied (>or=10 min or >or=9000 kJkg(-1)TS of specific energy) smaller molecular size materials were released to the liquid phase, which are considered to be found inside the cells indicating cell lysis.     

卧式搅拌罐的制造

根据卧式搅拌罐结构设计特点 ,确定了控制大小螺带的成型、搅拌器的焊接质量和变形、两个封头凸缘法兰的同心度、搅拌装置的安装以及第二个封头与壳体的焊接质量等施工工艺方案 ,实现了设备的高质量制造     

松辽盆地古龙凹陷上白垩统浊积岩沉积与成藏特征

应用钻井和测井资料区分地层及沉积环境,通过岩心观察和粒度分析判断沉积类型,用三维地震属性分析技术识别和刻画地质体,研究发现松辽盆地古龙凹陷上白垩统青山口组湖相区发育水道型浊积岩、带状浊积岩和湖底扇等3种类型浊积岩。水道型浊积岩发育在青山口组一段,以粉砂岩及细砂岩为主,沿古龙凹陷呈南北向线状展布,末端形成喇叭口状湖底扇,水道型浊积岩以形成低渗透岩性油藏为主,自然产能低,局部发育"甜点",需要储层改造才能获得较高产能;带状浊积岩发育在青山口组二段,岩性为粉砂—泥质粉砂岩,沿三角洲前缘向湖相区延伸,平面上呈宽带状,末端形成规模不等的湖底扇,带状浊积岩和湖底扇属于非常规储层,空间上相互叠置,形成连续型油藏,一般无自然产能,依赖水平井分段体积压裂才能获得工业产能。     

应用分层技术重新认识濮城油田沙二上油藏

濮城油田西区沙二上2＋3油藏为大厚层、严重非均质块状油藏,经过多年的注水开发,使储层孔隙结构改变．注采失调,油藏层间和层内矛盾突出,已进入特高含水开发后期,表现为高渗透层采出程度高、含水高,二、三类层动用程度低、剩余可采储量较大。因此,在油藏精细描述和剩余油研究的基础上,结合地质开发方案,开展了应用分层技术测试XP2—89、濮2—283、濮2—138井3口井的小层启动压力,通过测试成果量化认识层间非均质性,确认潜力层。通过将测试成果应用于区块改造、井网重组细分、认识剩余油分布,以及濮城南区沙二上2＋3油藏的分注分采治理．油藏地层压力回升．动液面和生产压差相对稳定,地层能量保持与利用状况得到改善,达到了控水增油的目的。该技术对高含水油藏后期注水开发进行了有益的探索．是重新识别油藏的又一工艺思路,具有一定的推广应用价值。