含钼催化剂的应用与前景

根据催化剂中含钼化合物成分的不同,分别综述了钴钼镍钼催化剂、钼的硫化物催化剂、多相氧化物催化剂、负载型钼基催化剂、钼杂多化合物催化剂、钼酸盐催化剂、新型碳化钼和氮化钼催化剂等在化学反应中的应用及机理,并对含钼催化剂的应用前景进行了展望.     

2010年3季度全球钼消费量下降

根据国际钼协报道，2010年3季度全球钼市场供应过剩4808t钼。全球钼产量增长1361t钼至6．0万t钼，钼需求量下降2268t钼至5．5万t钼，需求量下降是因为钢铁产量下降。     

焙烧钼精矿中氨不溶解钼直接测定分析方法研究

前言/Preface 焙烧钼精矿主要用来生产钼酸铵,其中所含氨不溶钼不可利用,随着氨不溶钼含量增加,氨浸渣中可溶钼含量也随着增加,严重影响了钼的回收率。对钼资源造成很大的浪费,为此焙烧钼精矿中氨不溶钼含量也引起极大的关注。目前对氨不溶钼的测定都采用总钼和可溶钼相减的方法,而总钼和可溶钼的含量都在60％左右,分析误差都在0.6,而客户对焙烧钼精矿中氨不溶钼含量的测定误差范围要求控制在0．3以内,间接测定难以达到。为此我们对焙烧钼精矿中氨不溶钼直接测定进行研究。     

中国钼金属制品发展现状分析

通过对未锻轧钼、已锻轧钼、粗钼丝、细钼丝、钼异型件等进行详细地分析,阐明了钼金属制品的生产现状;通过对钼金属制品进出口情况进行分析,描述了近年来钼金属制品的进出口发展现状;分析了中国钼金属制品与国外发达国家的差距以及国家出台的进出口政策对我国钼金属制品的影响,并指出了中国钼金属制品的发展前景.     

钼及钼合金溅射靶材的研究现状与发展趋势

钼及钼合金具有熔点高、导电导热性好、热膨胀系数低、耐腐蚀性能好及环境友好等优点,利用钼及钼合金加工制备的溅射靶材已广泛应用于电子电器、太阳能电池及玻璃镀膜等领域。本文介绍了对钼及钼合金溅射靶材的基本要求及制备方法,系统综述了目前国内外对钼、钼钛、钼钠、钼铌合金靶材的研究现状,并对钼及钼合金溅射靶材未来的发展趋势进行了展望。     

论当前国际钼的生产应用及贸易

自1989年以来,钼的产量及价格都是降低的,钼的总需量低于总产量。1989～1990年,日本钼丝、钼板的产量有所增加,但钼粉和钼棒的价格下降了。作者建议我国应该发展钼在冶金工业上的应用,加强钼的国际贸易,以提高我国钼企业的经济效益。     

钼市场发展趋势

介绍钼业的现状和发展趋势。重点分析钼市场发展和钼科研技术特点，指出了钼价格将必然下跌，钼全湿法冶金、钼化学制品、高温钼合金等是研究方向。本文分两部分，第一部分是钼市场发展趋势；第二部分是钼科技进步与研究展望     

钼粉制备技术及研究现状

钼粉制备技术直接影响到钼粉的品质,而钼粉的品质则影响钼及钼合金的性能,因而钼粉制备技术备受业界关注。主要介绍了工业化钼粉的传统制备方法,如氢气还原法、等离子还原法、羰基热分解法、溶胶-凝胶法,以及特殊用途的超细钼粉、纳米钼粉、高纯钼粉的制备方法。文章指出了各种钼粉制备技术的优缺点,以及所制得钼粉品质,并讨论了一些制备技术中的关键影响因素、过程机理。总之,选用不同的制备方法,可生产出满足各种需求的、性能和质量各异的钼粉产品。提高钼粉的纯度、产出率、生产效率、降低生产成本、发展特种制备设备,是钼粉制备技术的发展方向。     

德国钼业的创新与发展

德国钼资源匮乏,长期以来依靠进口钼精矿进行深加工生产出钼系列产品,如钼颜料、催化剂、添加剂、钼粉、钼合金和钼溅射靶材等。许多产品已走向世界,德国钼业的创新促进了钼业健康可持续发展。     

新型抑制剂在铜钼分离浮选中的应用研究

针对内蒙古某斑岩型铜钼矿产出的混合精矿，采用巯基类新型铜钼分离抑制剂CG4039、CG4006与NaHS组合用药，进行了铜钼分离小型闭路浮选试验和MPP扩大连续浮选试验。结果表明：在抑制剂总用量为20.80 kg/t的条件下，铜钼分离小型闭路浮选试验获得的钼精矿钼品位为53.24%,钼回收率为90.86%;相同条件下利用MPP进行铜钼分离扩大连续浮选试验，可获得钼品位48.92%、钼回收率87.92%的钼精矿，铜精矿钼品位为0.41%,铜钼分离效果较好，指标优于现场生产指标。     

Introduction to the special section on cognitive processes and psychotherapy.

Theoretical models featuring cognitive processes have played a fundamental role in advancing knowledge of psychopathology and its treatment and have emphasized the importance of cognition in psychotherapy. Recognition of the importance of cognition in psychotherapy has led to a number of questions that are addressed by the articles in this special section of the Journal of Consulting and Clinical Psychology. Cognitive therapy is well represented in the articles in this special section, but therapeutic procedures that do not represent typical cognitive therapy are also examined. The articles in this special section focus on homework in the modification of cognition, cognition in the treatment of anxiety in adults and in children, change in depressive cognitions in children, cognition and rapid change in the treatment of depression, and the role of cognition in the treatment and prevention of depression that is recurrent. Examination of these types of questions holds the possibility of advances in existing treatments and the possibility of innovations in new treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

球团链箅机回转窑工艺中氯和硫元素迁移规律

摘要：对链箅机回转窑工艺中各段球团样品进行实验分析,研究了氯元素和硫元素在链箅机回转窑工艺中的迁移规律,明晰了烟气中HCl的生成机制。结果表明,球团原料中的氯元素主要是以NaCl的形式存在,氯元素有一部分在链箅机抽风干燥段会转变成HCl气体并进入烟气,一部分在链箅机预热Ⅱ段之后以NaCl的形式汽化进入烟气,剩余的氯元素仍以NaCl的形式存在于成品球团矿中。烟气中的HCl气体是在抽风干燥段,由富含SO2的烟气与含水球团料层中的NaCl发生反应生成的,烟气中SO2转变成Na2SO4重新固定于料层中。在预热Ⅰ段和预热Ⅱ段,烟气中的SO2与原料中碳酸钙分解生成的游离CaO反应生成CaSO4,也会重新固定烟气中的SO2。     

某铀矿区水稻土—地表水铀含量对稻米铀含量的影响

以水稻土—地表水铀含量为视角,从水稻土剖面铀含量分布规律、水稻土与下伏岩体稀土元素特征、不同河流不同河段水稻土—地表水—稻米铀含量特征、水稻土与稻米铀含量关系4个方面研究721铀矿区稻米铀含量成因。结果表明,水稻土剖面铀含量从表层至半风化花岗质基岩层呈明显降低的特征,说明水稻土铀含量高的原因不是土壤母质铀含量高;岩石与水稻土稀土元素标准化模式均表现为向右倾斜型,均属轻稀土富集型,轻稀土分馏明显,表明水稻土为还原环境,吸附作用较强;不同河流不同河段水稻土—地表水—稻米铀含量平均值的特性均为上游最低、中游最高、下游次之。铀矿区地表水环境符合铀元素在水稻土中被平衡吸附的动力学条件,有利于铀元素在矿区内河流中游地区的水稻土中沉淀富集;正在采矿区水稻土与稻米铀含量具有高度的空间耦合性,呈指数正相关关系,相关系数0.749。矿区内河流沿岸稻米铀含量的分布特征是由铀元素的迁移途径决定的"采矿活动(铀尾矿露天堆放)→地表水→水稻土"。     

Flow Distribution Parameters in Relation to Flow Resistance in an Upflow Anaerobic Sludge Blanket Reactor System

The use of flow resistance in the distribution of flows is well known in traditional hydraulics. To evenly distributed flows, flow resistance forms the basis of flow distribution in pipes connected in parallel. Flow distribution in different zones of upflow anaerobic sludge blanket (UASB) reactors is well documented in existing literature, and so far modeling of flow distribution parameters, i.e., the fraction of inflow entering into the bed, the fraction of flow bypassing over the bed and entering into the blanket, and the fraction of inflow to the bed entering into the blanket, has remained empirical in nature. The role of flow resistance in the distribution of flows in UASB reactor systems is still unexplained. In this study, some of the available data on flow distribution parameters are analyzed to assess if there is any correlation between these parameters and flow resistance. It is found that with an increase in flow resistance in the UASB reactor system, the magnitude of short-circuiting flows at the reactor bed increases. Also, the flow distribution at the blanket and settler levels of UASB reactor systems is related to parameters influencing flow resistance. Some of the functional forms derived in this study are expected to form the basis for representing flow distribution in the simulation studies of UASB reactor performance.     

冀西北水晶屯金矿成矿控矿构造研究

水晶屯金矿床位于张宣幔枝构造轴部,水泉沟-大南山碱性角闪二长岩杂岩体的西缘。金矿化分布于尚义-赤城韧脆性剪切带中段。含金矿物主要为自然金和银金矿,赋存于石英、黄铁矿、方铅矿裂隙和胶结物颗粒间,矿石构造为细脉状、浸染状和团块状,围岩蚀变为硅化、黄铁矿化、绢云母化等。通过对本矿区的元素相关系数、硫、铅、氢、氧同位素特征等的研究分析,认为水晶屯金矿成矿物质主要是来源于深部的核幔物质,受构造控制明显。     

冷却速率对KR脱硫渣中硫析出行为的影响

KR脱硫渣中主要成分(CaO)为转炉冶炼的优质造渣原料,通过氧化性气氛将渣中硫脱除后可将其用于转炉冶炼.但由于炉渣冷却制度不同,渣中硫的析出行为和赋存状态会发生变化,对炉渣氧化脱硫效果产生影响.基于此,以合成渣的形式探究冷速对KR脱硫渣中硫析出行为的影响,旨在明确KR脱硫渣中硫赋存状态及析出行为与冷却速率的关系,为后续...     

Cohesive Sediment Characterization by Combined Sedimentation and Rheological Measurements

A laboratory characterization of cohesive sediment has been carried out in which data obtained from standard sedimentation and rheological measurements were combined in a determination of the critical solid concentration for the detection of elasticity in a weakly cohesive suspension. The corresponding storage modulus and shear stress are very critical in any in situ rheometry of sediments, especially in the study of mud-water surface erosion in a flume. Sedimentation results showed that particle size distribution rather than surface treatment controlled the rheological behavior of the suspension while the critical solid concentration for the appearance of three-dimensional space-filling network, showing some measurable elasticity in the suspension, occurred in the region of 0.015. This parallel between the consolidation behavior and shear rheology development for the flocculating system has been established. This technique could be an adjunct to the laboratory characterization of cohesive sediments for the estimation of critical shear stress for surface erosion, especially in a typical flume experiment under water wave pressure.     

Functions of Xyloglucan in Plant Cells

While an increase in the number of xyloglucan tethers between the cellulose microfibrils in plant cell walls increases the walls' rigidity, the degradation of these tethers causes the walls to loosen. Degradation can occur either through the integration of xyloglucan oligosaccharides due to the action of xyloglucan endotransglucosylase or through direct hydrolysis due to the action of xyloglucanase. This is why the addition of xyloglucan and its fragment oligosac-charides causes plant tissue tension to increase and decrease so dramatically. Experiments involving the overexpression of xyloglucanase and cellulase have revealed the roles of xyloglucans in the walls. The degradation of wall xyloglucan in poplar by the transgenic expression of xyloglucanase, for example, not only accelerated stem elongation in the primary wall, but also blocked upright-stem gravitropism in the secondary wall. Overexpression of cellulase also reduced xyloglucan content in the walls as cellulose microfibrils were trimmed at their amorphous region, resulting in increased cell volume in Arabidopsis leaves and in sengon with disturbed leaf movements. The hemicellulose xyloglucan, in its function as a tether, plays a key role in the loosening and tightening of cellulose microfibrils: it enables the cell to change its shape in growth and differentiation zones and to retain its final shape after cell maturation.     

Bridge Seismic Retrofitting Practices in the Central and Southeastern United States

This paper conducts a detailed review of the seismic hazard, inventory, bridge vulnerability, and bridge retrofit practices in the Central and Southeastern United States (CSUS). Based on the analysis of the bridge inventory in the CSUS, it was found that over 12,927 bridges (12.6%) are exposed to 7% probability of exceedance (PE) in 75-year peak ground acceleration (PGA) of greater than 0.20 g, and nearly 3.5% of bridges in the CSUS have a 7% PE in 75-year PGA of greater than 0.50 g. Since many of the bridges in this region were not designed with explicit consideration of the seismic hazard, many of them are in need of seismic retrofitting to reduce their seismic vulnerability. While several of the states in the CSUS have retrofitted some of their bridges, systematic retrofit programs do not currently exist. The review of retrofit practices in the region indicates that the most common retrofit approaches in the CSUS include the use of restrainer cables, isolation bearings, column jacketing, shear keys, and seat extenders. The paper presents an overview of the common approaches and details used for the aforementioned retrofit measures. This paper serves as a useful tool for bridge engineers in the CSUS as they begin to perform systematic retrofit of vulnerable bridges in the region.     

氯元素在高炉软熔滴落带分配规律

为了解氯元素在软熔滴落带的分配规律,对高炉内氯元素的反应行为进行热力学分析,同时研究了氯元素入炉量和炉料碱度对氯元素在高炉软熔滴落带渣、铁及焦炭中分配规律的影响。结果表明:随着入炉氯元素含量的增加,软熔滴落带铁和渣中的氯元素含量均不断增加,且渣中氯元素含量的增加幅度大于铁中氯元素含量的增加幅度。随着入炉氯元素含量的增加,软熔带总特征值(S值)逐渐减小,透气性逐渐增强,焦炭中的氯元素含量逐渐降低。随着入炉炉料碱度的增加,软熔滴落带铁中的氯元素含量无明显变化,渣中的氯元素含量增加,焦炭中的氯元素含量的大小主要受软熔带透气性的影响。