基于燃烧炯效率的电厂配煤模型

通过实验研究,综合考虑混煤指标计算、燃烧特征指数和燃烧火甩效率,提出了基于燃烧火用效率的电厂配煤模型,对配煤模型进行了求解,并以某2028t／h锅炉为对象,对三种单煤掺混进行了实例计算,结果表明,掺配比例2：1：9为最优解。     

关于动力配煤技术发展的探讨

对我国煤炭效率低、污染排放严重的状况进行了分析和探讨,指出要改善燃烧现状,须在大力发展洗选煤的同时,积极发展动力配煤技术。对动力配煤技术的经济效益和推广前景进行了预测,提出了动力配煤的发展途径与对策     

对混燃高铝煤提高除尘效率的分析探讨

能源是影响经济发展的重要因素，煤的品种和燃烧方式是直接影响着火力发电的经济效能。本文对配煤和混燃进行了阐述。并分析了其对锅炉效率和除尘效率的影响，进一步确定了配煤混燃的重要性和必要性。     

复杂物质化学(火用)的计算模型及计算式

本文以实际燃烧过程为计算模型,导出了通用而简便的复杂物质化学(火用)的计算式。结合我国煤炭资源,提出了煤灰分的平均标准比熵值及估算煤热值的关联式。这些给计算复杂物质的化学(火用)奠定了较好的基础,并可供工程实际使用。     

无烟煤对高炉喷吹用混合煤燃烧性的影响

采用非等温热重分析法研究了5种单种煤及9种混合煤的燃烧特性,根据TG-DTG曲线得出各试验煤样的着火温度、燃尽温度、最大燃烧速率和平均燃烧速率,并进一步计算出其燃烧特性指数。探讨了不同无烟煤对高炉喷吹用混合煤燃烧性的影响,并对不同粒度区间的混合煤燃烧性进行了研究。结果表明,混合煤的燃烧性与配入单种煤的燃烧性相关,同时也受其可磨性的影响,当配入无烟煤的燃烧性能相近时,无烟煤对混合煤燃烧性的影响主要取决于无烟煤的可磨性。     

动力配煤的数学模型及优化解

对配煤中的动力配煤进行研究,在建立数学模型的基础上,用实例来说明动力配煤方案的过程,得出优化解。根据这种方法可使动力配煤的原料成本降到最低,并减少使用低硫煤带来的热值变化问题,大大改善了煤燃烧状况,与烧原煤相比,可节约煤10%以上,烟尘排放量降低60%以上。既提高了效率,又保护了环境。     

不同液态渣排除率下煤燃烧产物成分与热电性质的计算

本文应用复相化学反应热力学平衡的模型理论,建立了煤的燃烧产物成分计算的数学模型,介绍了模型的解算方法,并在此基础上进行了燃烧等离子体热电性质的计算。文中运用上述模型,引入“液态渣排除率”的概念取代通常使用的“排渣率“,详细介绍了“不同液态渣排除率”下煤的燃烧产物成分与热电性质的计算。在国内首次针对燃煤磁流体发电中常采用的双级燃烧、前级排渣、后级添加种子产生等离子体的物理模型,并以淮南煤为实例进行了等离子体的成分和热电性质的计算。分析了排渣对燃气热电性质及对钾种子损失的影响。     

巷道高冒封闭火区燃烧状态及表面温度场演变规律

受早期小窑私挖乱采的影响,整合矿井往往面临废旧巷道或采空区遗煤多、漏风严重且复杂,煤自燃危险性大的难题,为了判断巷道高冒封闭火区的燃烧状态及其火区发展趋势,采用煤自燃低温氧化试验研究山西朔州某矿4+9号煤层火灾指标气体及其变化规律,现场收集火区内气体初步判断火区燃烧状态,最后利用红外热成像仪圈划火区表面温度区域,定位巷道顶煤火区表面高温点并分析火区巷道表面温度场变化趋势。研究结果表明:在煤低温氧化进程中CO,C2H6和C2H4等指标气体将在特定的温度等条件下自发产生,利用指标气体出现温度和随温度变化趋势,可以初步判断火区燃烧状态及发展方向;通过巷道表面温度场能够圈划浅部隐蔽火区大致范围,验证火区燃烧状态,判断火区发展趋势,预测煤自燃的危险性,能为火区危险性预报和治理提供可靠依据。研究成果对隐蔽火源燃烧状态和发展方向分析具有一定参考价值,能够为具有类似条件的矿区防灭火工作提供借鉴。     

基于CFD的城市生活垃圾焚烧炉燃烧优化

基于CFD,对城市生活垃圾焚烧炉进行了燃烧优化调整。采用扩散的床层模型和组分运输模型对垃圾在焚烧炉内的燃烧过程进行了数值模拟计算。在保持一、二次风比例不变的情况下,调整一次风的各级给风率,计算出各种燃烧条件下床层上方的炉膛烟气组分和温度分布。计算结果表明：一次风各级给风率的变化对垃圾焚烧炉内的气相燃烧及流场产生了较大的影响,热解燃烧段应采用均等配风;当一次风各级比例为1:3:3:2:1的时候,主炉膛出口CO浓度最小,平均浓度为0.159g/m3。     

1000W超超临界二次再热机组火用分析

针对国内某电厂1 000 MW超超临界二次再热机组的火用分布情况进行了研究.利用ASPEN PLUS软件建立机组模型,根据火用平衡方程,计算火用损失和火用效率,确定系统中能量损失的主要部位,为该电厂的运行优化和节能技术改造提供科学依据.研究结果表明:锅炉炉内燃烧火用损最大,其次是炉内换热面;汽轮机火用损主要集中在超高压缸和低压缸;该机组回热加热系统的火用效率较常规机组火用效率高约2.8%;低压缸更低的排汽参数使该机组凝汽器火用损约是常规一次再热机组的50%,能级利用更加合理.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that