废塑料与煤粉升温过程中的燃烧特性

试验研究废塑料燃烧特性。在空气和氧气的不同条件下,研究了不同品种废塑料颗粒和对比煤粉的燃烧特性。结果表明：在氧气条件下,不同品种废塑料升温时尾气中CO含量明显升高的温度都比在空气中的低30℃,CO2含量比在空气中的显著升高;在空气或氧气同一条件下,废塑料的CO2最大含量都比煤粉大幅提高,废塑料完成燃烧的温度比煤粉的低300~500℃。     

煤和塑料混熔喷吹技术研究

概述了国外高炉喷吹废塑料技术现状和国内研究进展,提出了煤与废塑料混熔高炉喷吹新工艺.对不同比例的废塑料与煤粉混合,在200 ℃的混熔温度下制成样品进行燃烧特性试验.结果表明:混熔样品具有良好的燃烧性能,开始燃烧温度和激烈燃烧温度都比煤粉低,塑料的存在对煤有提前燃烧作用,废塑料混熔比例在25%时燃烧时间较煤粉短,燃烧速度快;废塑料与煤混熔对高炉喷吹技术,理论上是可行的.     

在高炉喷吹不同比例废塑料颗粒与煤粉混合物燃烧性能的研究

运用系统分析的方法,对不同比例混合以及不同粒径大小的废塑料和煤粉混合物在高炉喷吹条件下的燃烧性能进行了对比研究。探明了混合物在炉腔内燃烧时的脱挥发分析出情况以及燃烧率的影响因素。分析结果表明,混合物中废塑料的添加比例和粒径的大小均是影响混合物燃烧性能的主要因素,从喷吹单一煤粉到喷吹废塑料与煤粉的比例达到5:5时,混合物的燃烧率从3.5%提高到35.5%。混合物的粒径大小从135~150μm变为30~50μm时,燃烧速率快了将近15%。     

气相成分和造粒条件对废塑料 燃烧和气化的影响

通过实验室研究了废塑料在不同造粒条件下所得的试在空气、氧气、二氧化碳等不同气氛下的燃烧特性并与煤粉进行了对比试验。研究表明：废塑料具有良好的燃烧性，用废塑料代替煤粉喷入高炉可获得较大的经济效益和社会效益。     

高炉中喷吹废塑料的可行性研究（Ⅰ）：——废塑料与煤粉的燃烧特性对比研究

为了研究向高炉中喷吹废塑料的可行性,对几种常见废塑料与高炉喷吹用煤粉的燃烧特性进行了对比研究。结果表明：废塑料具有良好的燃烧性能;废塑料的开始燃烧温度和激烈燃烧温度都比煤粉低,燃烧时间较煤粉短,燃烧速度快,燃烧灰尽少,因此更有利于高炉喷吹。     

在直吹管和风口内混合喷吹煤粉和废塑料的数值模拟

运用数值模拟方法,对废塑料和煤粉混合喷吹条件下直吹管和风口内的燃烧特性进行了研究。将废塑料与煤粉按不同比例混合,在不同粒径分布下喷吹时,分析了直吹管和风口内的挥发分析出和燃烧的规律。结果表明,随着混合燃料中废塑料比例增加,颗粒粒径减小,混合燃料的燃烧性能提高;从喷吹单一煤粉到喷吹煤粉与废塑料比为5∶5的混合燃料时,直吹管和风口内燃烧率从3.35%提高到36.31%。     

高炉大喷煤量与富氧率的合理搭配

为改善高炉冶炼效果,采用两段卧式燃烧炉模拟实际高炉喷煤工艺条件,系统研究了不同条件下富氧喷煤对煤粉燃烧过程的影响.在热风富氧的条件下,单种煤和混合煤的燃烧率随富氧率的增加都有提高,而且无烟煤燃烧率的提高幅度略高于烟煤. 缩小煤粉粒度、提高热风温度都有利于煤粉燃烧率的提高,但在鼓风富氧率比较高和煤粉粒度较细小时,煤粉粒度的变化对煤粉燃烧率的影响比较小,混合煤粉的燃烧率随热风温度升高而提高的幅度也略微下降.     

高炉用煤粉的混合添加剂研究

为强化煤粉的燃烧,改善其燃烧性能,从添加物质的助燃机理出发,通过TG/DSC和正交实验分析,研究了不同配比下的添加物质对煤粉的燃烧性能的影响.TG/DSC分析表明可选用CaCO3、MnO2和CeO2作为混合添加物质的主要组成.正交优化燃烧实验结果表明,不同配比下煤粉的燃烧速率和燃烧率均有较大提高,其中燃烧开始5 min的燃烧速率约提高0.45～0.91 mg/min,而煤粉的燃烧率平均约提高20%;添加物组成的最优化条件是w(CaCO3):w(MnO2):w(CeO2)=1.5:2.5:2.5,其中CaCO3水平的变动对实验结果有显著影响.     

单颗粒煤粉燃烧数学模型

建立了单颗粒煤粉燃烧数学模型，并模拟了不同条件下煤粉的燃烧过程。模拟给出了煤粒表面温度随燃烧时间的变化关系，燃烧率与燃烧时间及煤粒直径的关系，煤粒周转膜层中气相成分及温度的分布等。     

高炉煤粉燃烧率通用模型

建立了煤粉燃烧率通用模型,模型可以根据煤粉的工业分析值计算燃烧动力学参数并预测煤粉燃烧率.通过对比前人的实验数据,验证了模型的准确性,同时研究了影响高炉煤粉燃烧率的若干因素.研究结果表明:在高炉喷煤过程中,煤粉颗粒在2 ms左右就可以达到热风速度,由于煤粉颗粒在直吹管内停留时间短并且温度较低,因此在直吹管内煤粉不会发生燃烧.煤粉进入风口回旋区后,挥发分瞬间全部析出,并且颗粒粒径越小,挥发分开始析出时间越早.降低煤粉粒径和增加氧气体积分数均有利于提高煤粉燃烧率.氧气体积分数每增加1%,燃烧率提高2%.随着喷煤量的增加,煤粉燃烧率逐渐降低.当提高煤粉喷吹量时,为了保证较高的燃烧率,实际操作过程中应提高富氧率并适当降低煤粉粒径.      

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of rates of infection of two methods of emergency ventricular drainage

The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.