中国煤中硒的研究综述

分别从中国煤中硒的丰度、赋存状态和有机亲和性、迁移性和环境效应3个方面讨论了煤中硒的研究概况。硒在煤中相对于地壳中富集,不同地区、不同成煤期,煤中硒的含量差异很大;煤中硒大部分以有机结合态存在,无机结合态的硒大多数存在于黄铁矿中;在燃烧过程中,硒主要以气态的形式进入大气,或被极细飞灰吸附,污染环境,危害人体健康。     

煤矸石中汞、砷的研究进展

煤矿生产过程中伴生的大量煤矸石不仅占用土地资源,而且在露天堆放的过程中其含有的有害微量元素汞、砷等会进入自然环境中,对环境造成严重污染。通过总结,介绍了国内外学者对于煤矸石中汞、砷的研究成果。主要从煤矸石中汞、砷含量,煤矸石加热汞、砷释放,煤矸石中汞、砷淋溶析出以及煤矸石中汞、砷赋存形态四个方面进行总结。以期为更多学者对于煤矸石中汞、砷的研究工作提供一定的帮助。     

我国中微量元素肥料应用现状与前景分析

简述推广施用中微量元素肥料的必要性,介绍我国中微量元素肥料的施用与生产现状,讨论中微量元素肥料推广应用中存在的问题,提出我国中微量元素肥料将向多元化、高效化、多功能化的方向发展。     

中厚煤层综采工作面回采工艺之研究

为进一步提升中厚煤层中煤炭资源的有效利用率,但是在现实生产作业中,因为开采技术手段滞后性显著,导致中厚煤层资源开采效率长期偏低,故而应结合中厚煤层工作面的开采实况,不断完善回采工艺技术水平,以提升矿井工作面采煤效率,保证中厚煤层工作面高产高效。本文结合具体工程案例,对相关工艺技术的应用要点做出较详细探究。     

烟草及烟气中氨的分析方法研究进展

氨是烟草中天然存在的成分,在烟草中以NH4+形式存在,在烟草抽吸过程中以游离氨的形式被释放出来,而烟气中氨的含量对卷烟的吸味和劲头有很重要的影响。综述了烟草和烟气中氨的分析方法和技术,简要论述各种方法的原理和优缺点,并对烟草和烟气中氨的测定方法的发展趋势做了简要分析。     

耐火材料与洁净钢的关系

从化学热力学分析讨论了耐火氧化物及复合氧化物与钢液中平衡氧含量的关系 ,钢液中氧含量与氧势的关系 ,耐火氧化物与钢中硫含量 ,耐火氧化物及结合剂与钢中磷含量 ,耐火材料中残余水分及有机结合剂与钢中氢含量的关系 ,以及炼超低碳钢时的碳污染等问题。     

贮存对汽油中硫醇硫含量变化的测定方法研究

在进行汽油中硫醇硫的检测中发现,汽油中硫醇硫的含量随着贮存时间的延长而逐渐降低,为准确检测汽油中硫醇硫的含量,采取了相应的还原措施,使降低或“消失”的硫还原,并准确检测出原汽油中硫醇硫含量。     

空气气氛中烧成刚玉-氮化硅复合材料的研究

对刚玉-氮化硅复合材料在氮气中埋炭、空气中埋炭和空气 3种气氛中加热时可能发生的、对烧结有影响的重要反应进行了热力学分析,然后按m(Al2O3 ) : m(Si3N4 ) =62. 5: 37. 5的配比制成试样,在上述 3种气氛中于 1600℃保温 2h烧成,并对烧成后试样的性能、相组成以及空气气氛中烧成后试样的显微结构进行了分析。结果表明:在氮气中埋炭或空气中埋炭烧成时,材料的烧结情况没有在空气气氛中的好;在氮气中埋炭和空气中埋炭烧成后试样中分别生成了少量的β SiAlON或SiC,而在空气气氛中烧成后试样中出现了莫来石、石英和X相,残留了较多的β Si3N4;在空气气氛中烧成后,试样断面明显分为氧化层和非氧化层,其间有一沉积致密层。     

建设项目施工管理技术问题及措施分析

当前,在建筑工程施工中,机械化施工和计算机施工被广泛的应用在各类工程项目中,促使建筑施工整体水平的上升。特别是在高层建筑工程项目中,在施工中对于组织管理者提出了更高的要求。一个合格的组织者不但需要具备扎实的建筑理论基础水平,更应当具备相应的管理技术水平,在整个施工项目中涉及着方方面面的管理工作。在一个工程项目中,为了确保工程的施工质量和进度,就需要在项目中引进新的工艺技术,并在应用的同时发挥其应有技术。     

太阳能中温接收器的开发与研究

基于热管优良特性,将热管技术应用到中温（250-400℃）直接产蒸汽（DSG）太阳能接收器中,开发了中温热管接收器.采用电加热模拟中温热管接收器工作条件,通过试验研究了中温热管的传热性能,周向平均温差,根据试验结果分析了中温热管接收器工作过程中的可靠性和热效率,结果表明中温热管接收器内热管蒸发段周向平均温差低于13℃,热效率高于80%.     

Long-term residual value of North Carolina and Queensland rock phosphates compared with triple superphosphate

The effectiveness of large single applications of North Carolina reactive rock phosphate, Queensland non-reactive rock phosphate, and Calciphos, were compared to the effectiveness of superphosphate in field experiments in south-western Australia for up to 11 years after application. As measured using plant yield, superphosphate was the most effective fertilizer in the year of application, and relative to freshly-applied superphosphate, the effectiveness of the superphosphate residues declined to be about 15 to 65% as effective in the year after application, and 5 to 20% as effective 9 to 10 years after application. Relative to freshly-applied superphosphate, all the rock phosphates were 10 to 30% as effective in the year of application, and the residues remained 2 to 20% as effective in the 10 years after application. The bicarbonate soil test reagent predicted a more gradual decrease in effectiveness of superphosphate of up to 70% 10 years after application. For rock phosphate, the reagent predicted effectiveness to be always lower than for superphosphate, being initially 2 to 11% as effective in the year after application, and from 10% to equally as effective 10 years later. Therefore rock phosphates are unlikely to be economic alternatives to superphosphate in the short or long term on most lateritic soils in south-western Australia.     

Effect of catalysts in the quality of syngas and by-products obtained by co-gasification of coal and wastes. 1. Tars and nitrogen compounds abatement

The aim of this work is to analyse the possibility of using co-gasification technology to process coal mixed with wastes to take profit of its energy content and at the same time to minimize the environmental impact associated with the use of wastes and to diminish the costs of flue gas treatment. The addition to coal of different types of materials, like: pine based waste, petcoke and polyethylene (PE), was not found to give rise to any operational problems, regarding both the feeding system and gasification process and led to higher energy conversions, however, the gas presented higher tars and hydrocarbons content. Several catalysts were tested, such as, dolomite, olivine, nickel and magnesium oxides, zinc oxides and cobalt and molybdenum oxides. Catalyst action was analysed in tars release and also in ammonia compounds reduction. The presence of catalysts allowed increasing hydrogen release, whilst there was a decrease in hydrocarbons and tars contents. A nickel-magnesium oxide was the catalyst that led to the highest reduction in hydrocarbons and tars. This catalyst also led to the lowest NH₃ content in the fuel gas produced, due to the catalyst efficiency in NH₃ destruction.     

斯托克斯定律在炼油厂催化-常压装置的应用

介绍了斯托克斯(Stokes)定律与电脱盐(EDD)原理,叙述了2者结合在炼油厂常压-催化车间的应用,解决了油与无机盐及水的分离问题.(1)增加液-液旋流分离器,使进污水汽提塔的污水含油量降低了89%,解决了焚烧炉下火雨及炉膛超温的问题;(2)先后2次改造电脱盐流程及电脱盐罐,并应用鼠笼式平流电脱盐技术,使脱后含盐质量分数由8.74mg/L降为1.45 mg/L,含水的质量分数由0.43%降为0.11%,脱盐率由81.4%增加到96.4%.可保护催化剂,提高催化液收收率,降低成本,并稳定安全生产.     

提高学生综合与创新能力多种教学方式的探索

以《材料化学》、《复合材料》、《材料现代分析技术》和《材料导论》等专业课为载体,结合高分子科学与工程系科研优势和资源,探索启发式、参与式和专题讨论课等多种教学方式,将其应用到专业课教学中,以提高学生综合与创新能力为目标进行教学研究与实践。在理论课教学上注重思维训练,传授学习方法,提高学生学习自主性;注重课程之间对学生综合能力培养的协同作用。鼓励学生开拓思路,鼓励创新,配合教师完成每个教学环节,由此加深学生对课程知识的理解,有效地提高综合能力。     

中国基础磷化工产业现状与展望

以磷肥、黄磷、热法磷酸、三聚磷酸钠、饲料磷酸氢钙等产品为例,阐述了基础磷化工产业现状,针对基础磷化工产品同质化、技术等同化、市场过剩的局面,分析了产生问题的原因。指出基础磷化工必须淘汰落后产能,必须依靠技术进步降低生产成本,实现产品结构的升级与调整;而技术进步的重点在于实现原子经济效益、能源利用和劳动生产效率三者的最大化以及消耗的最小化,要不断开发满足社会需求的新产品。此外,还对相关的政策法规和规章制度提出建议。     

光解水制氢催化剂的研究进展

面对人类对能源的需求持续增长以及化石能源的日益枯竭和其带来的环境污染问题,开发太阳能对于解决能源问题具有非常重要的意义。利用太阳能分解水制氢是一种将太阳能转换为氢能的有效方式。根据近年来国内外太阳能分解水制氢催化剂的研究现状,分别对半导体光催化剂和金属配合物光催化剂进行综述,并且从可持续发展和实际应用的角度出发,针对各自的优缺点,提出今后应该开发具有高效且成本低廉的非贵金属配合物光催化剂,或尝试与半导体光催化剂结合应用,提高制氢效率。     

生成兴趣的大学教学

大学教育不仅仅是教给学生课本上的知识,更重要的是教会他们学习的方法,如何去获取有用的知识,以及如何利用所学的知识去解决实际问题。如何培养大学低年级学生的学习兴趣,如果引导他们主动去学习,在化学实验课上,又如何主动细致的去完成动手部分的学习,将是我们大学教学工作中急需要改进和提高的重要部分。     

安克锰锌在荔枝树上施用的残留代谢消解规律与安全性评价

安克锰锌是烯酰吗啉两个异构体和代森锰锌组成的多元混合制剂。试样经粉碎、溶剂浸泡提取、混合柱净化,用气相色谱测定烯酰吗啉和代森锰锌母体(CS2),液相色谱测定代谢物乙撑硫脲(ETU)。仪器最低检出量:烯酰吗啉为1.436×10-12g,代森锰锌母体1.326×10-10g,ETU2.5×10-10g,最低检出浓度依次为0.02、0.025、0.02mg/kg,方法回收率依次为86.4%～90.8%、89.2%～95.9%、89.10%～95.13%;标准偏差为0.53～4.34;变异系数为0.58%～4.62%。安克锰锌在果皮中的消解方程广西和广东分别为C=1.2719e-0.1975T和C=1.045e-0.1972T,半衰期(T/2)均为3.5d;土壤中分别为C=0.8734e-0.1187T和C=0.6171e-0.1146T,半衰期(T/2)=6d;最高剂量250倍、最多施3次,最短距收期7d,在果肉中均未检出,果皮和土壤中的残留仅分别为0.1385～0.1745mg/kg和0.3105～0.3415mg/kg,均低于欧共体规定代森锰锌MRL值0.5mg/kg。     

绿色环保意识的趋向

随着消费者环保意识的提高,人们除了认清绿色环保能对社会和全世界起到巨大的促进作用,还认为绿色环保能够直接、积极地反映其社会地位,在某种程度上反映出消费者自己的绿色环保意识。介绍了消费者对"绿色化"的认识,对"绿色产品"的期望以及生产厂家对"绿色原料"的认证和对"可持续发展"所做的贡献。     

Physical and frictional properties of non-treated and steam exploded barley, canola, oat and wheat straw grinds

During storage and handling, accurate knowledge of the physical and frictional behaviors of biomass grinds is essential for the efficient design of equipment. Therefore, experiments were performed on non-treated and steam exploded barley, canola, oat and wheat straw grinds to determine their coefficient of internal friction and cohesion at three hammer mill screen sizes of 6.4, 3.2 and 1.6 mm, three normal stress values of 9.8, 19.6 and 39.2 kPa at 10% moisture content (wb). At any specific hammer mill screen size, the geometric mean particle size and bulk density of non-treated straw was significantly larger than steam exploded straw. The bulk density of ground straw significantly increased with a decrease in hammer mill screen sizes. The steam exploded straw grinds resulted in higher coefficient of internal friction compared to non-treated straw grinds primarily because of lower bulk densities. The coefficient of friction for non-treated barley, canola, oat and wheat straw were in the range of 0.505 to 0.584, 0.661 to 0.665, 0.498 to 0.590, and 0.532 to 0.591, respectively. Similarly, the coefficient of friction for steam exploded barley, canola, oat and wheat straw were in the range of 0.562 to 0.738, 0.708 to 0.841, 0.660 to 0.860, and 0.616 to 1.036, respectively, which were higher than non-treated straw of the kind. Power, logarithmic or exponential equations were developed to predict the coefficient of internal friction and cohesion with respect to average geometric mean particle sizes for non-treated and steam explode barley, canola, oat and wheat straw grinds.