粒度对煤粒燃烧和热解影响的理论分析

在化学热力学和动力学理论中引入表面项,并由此来分析和讨论粒度对煤颗粒燃烧和热解反应的影响规律.研究结果表明,煤颗粒的粒度对其燃烧和热解反应的热力学性质和动力学参数有明显的影响,粒度越小,影响越大;减小煤颗粒的粒径,化学反应的吉布斯函数差减小,煤颗粒燃烧和热解的趋势增大,使着火温度和热解温度降低,自燃容易发生;并且减小煤颗粒的粒径,其摩尔表面能增大,导致其燃烧和热解的表观活化能降低和速率常数增大,使煤颗粒的燃烧和热解速率加快,使转化率、燃尽度和热解度增加.     

迈向循环利用型社会

人造草地和人工渔礁,电池外壳及桥墩,地毯底衬和建筑用包,排水过滤器,河堤,地砖,垫圈,港口和码头,绝缘和工业涂料,牲畜棚地垫和垃圾填埋工程,田径球类运动场地和家具,屋顶材料和路面,鞋底和坚实的车轮,隔音屏障和防振垫。如此多样化的应用和产品之间有什么共同之处？一句话,它们都是用废旧轮胎再生材料为原材料生产出来的。     

浅析儿童气管和支气管异物、中暑和溺水的诊断和治疗

目的研究儿童气管和支气管异物、中暑和溺水的诊断和治疗方法。方法根据患儿临床表现,针对气管和支气管异物、中暑和溺水的患儿采取不同的有针对性的治疗措施。     

HFE7100和HFE7500的热物理性质

为了获得氢氟醚HFE7100、HFE7500的热物理性质参数,补充现有数据不足,为其作为电子元器件的冷却介质、工业清洗剂等工程应用提供技术支持,利用瞬态热线法测量了常压下HFE7100和HFE7500的热导率,并用表面光散射法测量了HFE7100和HFE7500的液相黏度和表面张力。HFE7100和HFE7500的热导率和液相黏度均关联成温度的多项式函数,HFE7100热导率和黏度的实验值和关联式的平均绝对偏差分别为0.37%和1.19%,HFE7500热导率和黏度的实验值和关联式的平均绝对偏差分别0.08%和1.10%。利用改进的van der Waals关联表面张力和温度的关系,HFE7100和HFE7500的表面张力的实验值和关联式的平均绝对偏差分别为0.03 mN·m^-1和0.02 mN·m^-1。获得的HFE7100和HFE7500的热导率、黏度和表面张力实验数据及方程,可为其工程应用提出数据支持。     

橡胶软管胶料的配合和混炼工艺

在过去数年中,橡胶软管胶料配合、混炼和压出工艺的基本原理和硫化变化不大,无论国外和国内的胶料工艺都大同小异。但是,由于生产规模的扩展和越来越多系列的聚合物、弹性体以及新材料的出现,也由于对更高的生产效率和节能的要求,对新技术和加工方法也在不断地加以检验和采用。的确,对用于胶管方面的高质量胶料进行满意的混炼和配合是很重要的。系统地介绍了橡胶软管配合和加工工艺方面的技术进展。     

油气储运技术的创新研究

石油和天然气的储存和运输,即石油和天然气资源的储存和运输,是有效利用石油和天然气资源的重要先决条件。随着中国经济社会的快速发展和油气储运技术的更新和发展,油气储运业面临着重大机遇和挑战。针对油气储运技术发展现状,确定基于安全,环保,节能的油气储运技术要不断的创新,才能促进油气进一步发展。     

二氧化碳催化加氢催化剂研究进展

介绍了近年来二氧化碳催化加氢合成烃类、甲醇和甲酸过程使用的催化剂和助剂研究进展。叙述了烃类合成的Fe基催化剂、各种助剂和载体及其作用,并比较Fe基催化剂和其他催化剂对烃类产物分布的影响;甲醇合成的Cu基催化剂、ZnO载体和各助剂对CO2转化率和甲醇选择性的影响;甲酸合成中使用的均相过渡金属（钌和铑）配合物催化剂和固载催化剂。认为目前对助剂、载体和从反应机理揭示助剂、载体的作用研究不够,而了解助剂、载体和基本元素之间的相互作用．将能更精准地选择助剂和载体,更好控制反应条件。     

漫话办学教学与师资

1 关于学校"三风"建设的话题 每所学校都很关心和注重学风、教风和校风这"三风"的建设.这是因为它直接关系到和影响着教育、教学和学习质量的好差,学校品位、形象和声誉的高低,归根结底决定着人才培养的成效和规格.在这种认识的基础上,我又翻看到历任北大、北师大、女师大和厦门大学教授并留学哈佛的林语堂(1895-1976)博士的一段论述.     

善于学习,敢于超越,勇于实践,为我所科学发展添光彩——在青委会成立大会上的讲话

<正>2012年春天已经迈开了轻盈的步伐,悄悄的向我们走来,带给我们是梦想和温暖、机遇和希望、热情和信心。今天,我所召开大会隆重的成立青年委员会,我首先感谢所领导班子全体成员对青年的支持和理解,作为第一届青年委员会的主任,我想提出开展主要活动和措施,供大家参考;也谈谈个人的几点体会和看法,与青年交流和共勉。     

设备管理规程的编制方法研究

本文简要介绍了设备使用、操作、维护保养、检修和安全操作规程的定义以及区别和相互间的关系;编制规程的一般规定和程序;重点介绍了设备操作、维护保养和检修规程的编制方法和内容.     

Confocal microscope—A valuable tool for examining wood-coating interface

The suitability of confocal laser scanning microscopy (CLSM) in examining a wood-coating interface was evaluated using a clear coating system. A comparison of the images of the wood-clear coating interface obtained using CLSM and light microscopy (LM) showed a marked superiority of CLSM in revealing the details of the physical nature of the interaction between the clear coating and the wood cell walls in the surface layer. The most distinct advantage of CLSM was in its ability to clearly resolve penetration of the coating into very fine cracks in cell walls, details not obtainable with LM. The information presented here demonstrates that CLSM has the potential to greatly enhance our understanding of the physical aspects of an interaction between the wood and coating at the interface.     

机制砂岩性与级配对混凝土抗硫酸盐侵蚀性能的影响

为了探究不同岩性、不同级配机制砂对混凝土性能的影响,对三种不同岩性机制砂混凝土及天然河砂混凝土的工作性和抗压强度进行研究。此外,对比分析了四种混凝土在干湿循环制度下的抗硫酸盐侵蚀性能。结果表明,天然河砂混凝土的工作性优于机制砂混凝土,钙质机制砂混凝土的工作性略好于硅质机制砂混凝土。机制砂混凝土的抗压强度优于天然河砂混凝土,在硫酸盐侵蚀循环作用下的力学性能变化趋势与天然河砂混凝土基本一致。在相同级配条件下,机制砂混凝土的抗蚀系数高于天然河砂混凝土;机制砂岩性并不会对混凝土抗硫酸盐侵蚀性能带来负面影响。级配良好的机制砂可以增强混凝土抗压强度和抗硫酸盐侵蚀性能。     

Functional properties of proteins in foods

The measurement of functionality of protein food ingredients has developed somewhat haphazardly, probably due to the wide range of proteins used as ingredients and the diversity of foods. Studies of the physiochemical properties of proteins should enable prediction of a proteins response to process environments and prove more fruitful than many of the empirical measurements of functionality. The effects of pH, salt type and concentration on the phase behaviour of the oilseed globulin and arachin, demonstrates the complexity of protein solubility and the inadequacies of simple tests that have arisen. Studies of the effects of salts and conditioning on meat fibres, coupled with measurement of the location of water in pellets from water holding tests enable the latter to be applied with increased confidence. Comparison of the endothermic transitions observed on heating with the development of storage and loss moduli allow the contributions of domains of skeletal muscle myosin to gel structure to be investigated.     

聚氨酯涂覆胶辊的研制

本文论述了彩色金属薄板生产用聚氨酯涂覆胶辊材料的合成原料选择、配方设计和工艺路线、以及力学性能和溶胀性能等．从测试数据看出．与美国进口样品相比．其力学性能和溶胀性能普遍优于后者。     

Factors affecting levels of some phenolic compounds,digestibility, and nitrogen content of the mature leaves ofBarteria fistulosa (Passifloraceae)

Levels of total phenolics, condensed tannins, acid detergent fiber, pepsin/cellulase digestibility, and nitrogen in mature leaves of 26 individuals of the ant-plant,Barteria fistulosa, have been determined. Analysis of the results in terms of the presence or absence of ants and the position of the branch from which the leaves were collected showed no relationship with concentrations of phenolics or fiber and only a weak relationship with digestibility and nitrogen. By contrast, light intensity strongly influenced levels of phenolics, notably condensed tannins, so that mature leaves of individuals growing in direct sunlight were less digestible and appeared to be of lower quality as food for herbivores than did mature leaves of individuals in shaded positions. Possible reasons for the variation in condensed tannin levels are discussed.     

Effect of some floral scents on host finding by thrips (Insecta: Thysanoptera)

The role of floral scents in host location by flower-dwelling thrips is investigated by experiment in the field. The scent of anisaldehyde significantly increased the catches of seven species of flower-dwelling thripid, but had no significant effect on three species of cereal thripid and one species of flower-dwelling aeolothripid. The catches of white (without UV) traps were increased by a factor of 3.3 to 8.3 in the presence of the scent.     

Aggregation pheromone system of adult gregarious desert locust schistocerca gregaria (forskal)

Six electrophysiologically active aromatic compounds, viz., anisole, benzaldehyde, veratrole, guaiacol, phenylacetonitrile, and phenol, were identified in the volatiles of older-adult male desert locust. Young adults and females of all age groups produced none or only trace quantities of these compounds. Comparison of the aggregation responses of young and older adults to the crude, older-adult, volatile extract and different synthetic blends of the six compounds showed that the aggregation pheromone system of the adult gregarious locust consists of phenylacetonitrile, guaiacol, phenol, and benzaldehyde. Like the crude volatile extract of older males, neither the synthetic blend of the six compounds nor the adult pheromone blend evoked any significant aggregation responses from nymphs. These results confirm our previous report of sexual differentiation in the production of adult aggregation pheromone in the desert locust and of the evidence of two distinct aggregation pheromone systems in the two stages of the insect.     

合成气经二甲醚羰基化及乙酸甲酯加氢制无水乙醇的研究进展

合成气经二甲醚羰基化及乙酸甲酯加氢路线制无水乙醇技术因具有诸多优点而备受市场关注。本文综述了该工艺的核心反应机理和最近研究进展。主要探讨了丝光沸石8元环与12元环对羰基化反应的作用。阐明了如何通过调变丝光沸石8元环与12元环的活性位来提高羰基化催化剂的活性与稳定性。评述了铜纳米粒子的粒径、分散度以及Cu⁺与Cu⁰的分布等特点对铜基催化剂加氢催化活性的影响。提高乙醇选择性与催化剂稳定性是该研究的重点与难点。指出羰基化催化剂的优化重点是调变丝光沸石的孔道结构,加氢催化剂的发展方向是构建高分散度的铜纳米粒子,并在反应过程中保持稳定。     

Kondensation von Dampfgemischen nicht mischbarer Flüssigkeiten

Condensation of Vapour Mixtures of Immiscible Liquids In contrast to the condensation of pure vapours and vapour mixtures of miscible liquids, the condensation of vapour mixtures forming immiscible or only partly miscible condensates is still poorly understood. Models describing heat transfer in the latter kind of condensation deviate so much from one another, not only quantitatively but also qualitatively, that reliable design of condensers is impossible. The reason lies primarily in the variety of flow patterns of two‐phase condensates, which range from pure droplet to pure film condensation. This paper surveys literature reports of the flow patterns and heat transfer occurring during condensation of vapour mixtures in the miscibility gap of their liquids. Qualitative knowledge in this condensation area is shown to be satisfactory. Several models have been proposed for heat transfer. However, the heat transfer coefficients obtained from these models differ too much from one another to allow one to choose the “best” correlation. Our own experiments with a eutectic benzene–water mixture on a vertical tube show that the calculation scheme proposed by Hoon and Burnside leads to acceptable results.     

Molecular mechanics modelling of interfacial energy and flexibility on cellulose

Molecular mechanics modelling is used to calculate the energies of interaction, hence the molecular level energy of adhesion at the interface with crystalline cellulose I of three different photopolymerizable primers and of a polyester varnish at the interface with the primer/cellulose assembly. The energy of interactions for just one of the primers with the statistically most common conformation of amorphous cellulose has also been obtained for comparison. Experimental results of adhesion by a standard peel test and by thermomechanical analysis, in which the effect of viscoelastic energy dissipation by crack tip propagation has been respectively minimized or is not present, hence in which the energy of interfacial interaction is nothing else but the work of adhesion, correlated well with the energies of interaction calculated by molecular mechanics. An equation correlating the energy of interaction at each finish/cellulose interface with the deflection derived by thermomechanical analysis, and with the number of internal bond rotational degrees of freedom as well as the degree of networking of the finish, has been derived and is presented. A relationship between the intrinsic fracture energy Go and the molecular mechanics-derived energy of interaction at the interface equating this to the square of the work of adhesion is obtained and is presented.