火焰层析成像的最新进展(英文)

To reduce greenhouse gas emissions from fossil fuel fired power plants,a range of new combustion technologies are being developed or refined,including oxy-fuel combustion,co-firing biomass with coal and fluidized bed combustion.Flame characteristics under such combustion conditions are expected to be different from those in normal air fired combustion processes.Quantified flame characteristics such as temperature distribution,oscillation frequency,and ignition volume play an important part in the optimized design and operation of the environmentally friendly power generation systems.However,it is challenging to obtain such flame characteristics particularly through a three-dimensional and non-intrusive means.Various tomography methods have been proposed to visualize and characterize flames,including passive optical tomography,laser based tomography,and electrical tomography.This paper identifies the challenges in flame tomography and reviews existing techniques for the quantitative characterization of flames.Future trends in flame tomography for industrial applications are discussed.     

介观尺度多孔介质燃烧室内火焰分布的电容层析成像(英文)

This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to varied air/fuel ratio in a meso-scale combustor.Combustion phenomena including igniting,quenching and unsteady combustion have been visualized using ECT.The method of metallization protecting ECT sensor from high temperature damage and the novel calibration method adapted to ECT monitoring of unknown permittivity flame have been shown to be successful.At the same time,electrical nature of combustion and dielectric characteristics of hy-drocarbon flame were studied.The relationship between flame permittivity and state parameters of combustion gas was demonstrated preliminarily.     

基于岭估计的化工过程测量置信水平研究(英文)

Ordinary least squares （OLS） algorithm is widely applied in process measurement, because the sensor model used to estimate unknown parameters can be approximated through multivariate linear model. However, with few or noisy data or multi-collinearity, unbiased OLS leads to large variance. Biased estimators, especially ridge es-timator, have been introduced to improve OLS by trading bias for variance. Ridge estimator is feasible as an esti-mator with smaller variance. At the same confidence level, with additive noise as the normal random variable, the less variance one estimator has, the shorter the two-sided symmetric confidence interval is. However, this finding is limited to the unbiased estimator and few studies analyze and compare the confidence levels between ridge estima-tor and OLS. This paper derives the matrix of ridge parameters under necessary and sufficient conditions based on which ridge estimator is superior to OLS in terms of mean squares error matrix, rather than mean squares error. Then the confidence levels between ridge estimator and OLS are compared under the condition of OLS fixed sym-metric confidence interval, rather than the criteria for evaluating the validity of different unbiased estimators. We conclude that the confidence level of ridge estimator can not be directly compared with that of OLS based on the criteria available for unbiased estimators, which is verified by a simulation and a laboratory scale experiment on a single parameter measurement.     

高温烟气伴流的温度和氧浓度对甲烷/氢气扩散火焰的影响(英文)

This paper investigates the effects of coflow O2 level and temperature on diffusion flame of a CH4/H2 jet in hot coflow(JHC) from a burner system similar to that of Dally et al.The coflow O2 mass fraction(y*O2) is varied from 3% to 80% and the temperature(T*cof) from 1200 K to 1700 K.The Eddy Dissipation Concept(EDC) model with detailed reaction mechanisms GRI-Mech 3.0 is used for all simulations.To validate the modeling,several JHC flames are predicted under the experimental conditions of Dally et al.[Proc.Combust.Inst.,29(1),1147-1154(2002)] and the results obtained match well with the measurements.Results demonstrate that,when y*O2 decreased,the diffusion combustion is likely to transform from traditional combustion to MILD(Moderate or Intense Low-oxygen Dilution) combustion mode.When cof T* is higher,the temperature distribution over the whole domain trends to be more uniform.Reducing y*O2 or cof T* leads to less production of intermediate species OH and CO.It is worth noting that if y*O2 is high enough(y*O2>80%),increasing y*O2 does not cause obvious temperature increase.     

环丙沙星、诺氟沙星、氧氟沙星在1 mol·L~(-1) HCl中对碳钢的缓蚀性能及机理研究(英文)

The inhibiting effect of ciprofloxacin,norfloxacin and ofloxacin on the corrosion of mild steel in 1 mol·L-1 HCl and the mechanism were studied at different temperatures using mass loss measurement,electrochemical method,and X-ray photoelectron spectroscopy(XPS) .Effective inhibition was shown by mass loss,potentiodynamic polarization and impedance spectroscopy measurement.The corrosion rate of the metal in the mass loss measurement,and the corrosion reaction on cathode and anode in the electrochemical measurement were accelerated when temperature was increased.XPS results showed that the inhibitors adsorbed effectively on the metal surface.     

基于区间二型模糊推理的双容水箱液位控制系统研究(英文)

For dealing with large static error due to poor immunity of the traditional fuzzy control, a novel interval type-2 fuzzy control system is proposed. By extending the typical membership functions to interval type-2 membership functions, the proposed control system can efficiently reduce the uncertain disturbance from real environment without increasing the design complexity. The simulation results on the water tank level control system showed that the proposed method succeeded in better static and dynamic control with stronger robust performance than the traditional fuzzy control method.     

预测生物质颗粒热解时热损失影响的分析模型(英文)

This paper presents the combined influence of heat-loss and radiation on the pyrolysis of biomass parti-cles by considering the structure of one-dimensional, laminar and steady state flame propagation in uniformly pre-mixed wood particles. The assumed flame structure consists of a broad preheat-vaporization zone where the rate of gas-phase chemical reaction is small, a thin reaction zone composed of three regions：gas, tar and char combustion where convection and the vaporization rate of the fuel particles are small, and a broad convection zone. The analy-sis is performed in the asymptotic limit, where the value of the characteristic Zeldovich number is large and the equivalence ratio is larger than unity （i.e. u 1？ ≥ ）. The principal attention is made on the determination of a non-linear burning velocity correlation. Consequently, the impacts of radiation, heat loss and particle size as the de-termining factors on the flame temperature and burning velocity of biomass particles are declared in this research.     

SCIE中化学工程高引用文章的文献计量学分析(英文)

This study aimed to identify and to analyze characteristics of top-cited articles published in the Web of Science chemical engineering subject category from 1899 to 2011.Articles that have been cited more than 100 times were assessed regarding publication outputs,and distribution of outputs in journals.Five bibliometric indicators were used to evaluate source countries,institution and authors.A new indicator,Y-index,was created to assess quantity and quality of contribution to articles.Results showed that 3828 articles,published between 1931 and 2010,had been cited at least 100 times.Among them 54% published before 1991,and 49% top-cited articles originated from US.The top eight productive institutions were all located in US.The top journals were Journal of Catalysis,AIChE Journal,Chemical Engineering Science and Journal of Membrane Science.Y-index was successfully applied to evaluate publication character of authors,institutions,and countries/regions.     

基于改进GSO的裂解炉原料切换策略研究(英文)

The scheduling process of cracking furnace feedstock is important in an ethylene plant. In this paper it is described as a constraint optimization problem. The constraints consist of the cycle of operation, maximum tube metal temperature, process time of each feedstock, and flow rate. A modified group search optimizer is pro-posed to deal with the optimization problem. Double fitness values are defined for every group. First, the factor of penalty function should be changed adaptively by the ratio of feasible and general solutions. Second, the“excel-lent”infeasible solution should be retained to guide the search. Some benchmark functions are used to evaluate the new algorithm. Final y, the proposed algorithm is used to optimize the scheduling process of cracking furnace feedstock. And the optimizing result is obtained.     

添加剂EDTA对氢氧化镁反应结晶过程的影响(英文)

The effects of additive ethylenediaminetetraacetic acid (EDTA) on crystallization process were investigated by the induc-tion time of MgSO4-NaOH system. Nucleation and growth rates, growth mechanism and particle size distribution of magne-sium hydroxide precipitation were involved with. The induction time in unseeded and seeded precipitation of magnesium hydroxide with and without additive EDTA was measured. The conductivity method was used to determine the induction period. Theoretical relations of the induction time and supersaturation ratio for different growth mechanisms and a combined analysis on the induction time were applied to determine nucleation and growth rates. The growth mechanism of magnesium hydroxide precipitation was dis-closed by analyzing the experimental data with and without additive. The analysis on induction time indicated that additive EDTA had a significant influence on both nucleation and growth of magnesium hydroxide precipitation. The mechanism underlying the effect of EDTA on crystal growth was 2-dimension nucleation-mediated growth model.     

国外含磷系、卤素系阻燃聚氨酯材料的研究进展

介绍了国外含磷系、卤素系阻燃聚氨酯材料研究状况,当今研究重点主要集中在有机磷酸酯添加型阻燃剂,反应型阻燃剂以及具有阻燃特性的聚氨酯黏结剂,建议今后应将提高阻燃聚氨酯材料的综合性能和阻燃机理作为研究的重点。     

无卤阻燃含磷环氧树脂的研究进展

无卤阻燃含磷环氧树脂中的磷成分具有气相和凝聚相的双重阻燃作用,且材料本身降解产物不产生可持续性环境污染物,因而作为环境友好型阻燃材料而被广泛研究。本文综述了近年来关于含9,10-二氢-9-氧杂-10-磷杂菲10-氧化物(DOPO)环氧树脂体系（包含DOPO环氧树脂、DOPO基固化剂和添加型DOPO改性聚合物）、磷酸酯型环氧树脂体系（包括磷酸酯环氧树脂、环状磷酸酯环氧树脂、磷酸酯型固化剂）、含磷固化剂以及磷腈环氧树脂和磷-硅环氧树脂的研究进展,介绍了每种体系的性能特点。总结了含磷环氧树脂的阻燃性能、热性能、阻燃机理,以及磷-氮协同效应、磷-硅复合二元体系的阻燃机理。     

含磷PBT共聚酯的制备及成纤应用研究

采用PTA,BDO和磷类阻燃剂三元共聚的方法制备了含磷共聚酯并研究了阻燃剂添加量对共聚酯性能的影响。研究表明随阻燃剂含量的增加,极限氧指数和熔融指数先随阻燃剂含量的增加而快速增加,后缓慢增加;熔点随阻燃剂含量近似呈线性降低。采用一个配方进行了聚合放大、纺丝及加弹应用实验,实验表明制备的共聚酯与小试样品性能相当,无明显的聚合放大效应,纺丝及加弹过程稳定;所得POY丝及加弹丝的强度稍高,染色性能好,其他指标与空白PBT丝相当。     

无卤阻燃聚对苯二甲酸丙二酯的研究

摘要：使用无卤磷系阻燃剂二乙基次膦酸铝(ADP)和氮系阻燃剂三聚氰胺氰尿酸盐(MCA)作为阻燃剂,马来酸酐接枝聚烯烃弹性体(POE-g-MAH)为增韧剂,对聚对苯二甲酸丙二酯(PTT)进行阻燃改性,分别研究两种不同体系阻燃剂对PTT阻燃性能和力学性能的影响,并通过热失重(TG)分析仪、差示扫描量热(DSC)仪,扫描电子显微镜(SEM)对其阻燃机理进行研究。实验结果表明,添加质量分数10%的ADP时,阻燃PTT达到V-0级,极限氧指数(LOI)达到30.0%,ADP主要在凝聚相中发挥阻燃作用;添加质量分数20%的MCA时,阻燃PTT达到V-0级,LOI达到24.9%,MCA主要在气相中发挥阻燃作用;ADP与MCA的加入都降低了阻燃PTT的综合力学性能。TG和DSC测试结果说明,ADP与PTT间的相容性良好,可以有效地促进PTT成炭并提高材料的阻燃性能;MCA与PTT间的相容性较差,且MCA对PTT成炭没有影响。添加质量分数5%的ADP和10%的MCA时,阻燃PTT达到V-0级,LOI达到26.9%,说明ADP与MCA具有协效阻燃作用。     

磷系阻燃剂的发展及应用研究

摘要：简述了磷系阻燃剂的相对优势及阻燃机理,重点综述了红磷、磷酸酯、膦酸酯等磷系阻燃剂的研究进展、应用以及未来发展方向。指出未来磷系阻燃剂将朝着以下几个研究方向发展：提高阻燃剂的热稳定性及与材料的相容性;磷系阻燃剂的超细化;制备含有多官能团,且含有多种阻燃元素一体的高效阻燃剂;研究具有增塑、防老化、防水、抗静电等多功能阻燃剂;开发高效、低烟、低毒、对材料性能影响小的阻燃剂。     

Influence of organophosphorus inhibitors on the structure of atmospheric lean and rich methane-oxygen flames

The inhibition of atmospheric laminar methane-oxygen flames of various compositions by trimethyl phosphate was studied experimentally and by numerical modeling using mechanisms based on detailed kinetics. The H and OH concentration profiles in flames with and without the addition of trimethyl phosphate were measured and calculated. It was shown that the addition of the inhibitor reduced the maximum (in the reaction zone) concentrations of H and OH in lean and rich flames. The concentration reduction was higher in rich flames than in lean flames. The concentration profiles of the phosphorus-containing products PO, PO₂, HOPO, HOPO₂, and (HO)₃PO in lean and rich flames stabilized on a flat burner were measured and calculated. Tests of the previously developed model of flame inhibition by phosphorus compounds showed that the model provides adequate predictions of many experimental results. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 2, pp. 23–31, March–April, 2007.     

反应型含磷阻燃剂对不饱和树脂阻燃性能的研究

本文以羟乙基甲基丙烯酸酯磷酸酯(HEMAP)作为不饱和树脂的反应型含磷阻燃剂,研究其对不饱和树脂阻燃性能的影响。当不饱和树脂加入5份HEMAP后,固化物的极限氧指数为32.5。热重分析结果表明,当不饱和树脂加入HEMAP量从0增加到20份时,氮气下10%失重温度和最大分解温度明显降低,P-O-C键的提前分解产生磷酸类物质,有效阻止了不饱和树脂的进一步分解,800℃残炭率从3.8%提高到31.4%;空气下500℃下初级残炭率从20.6%提高到46.3%。用动态热机械分析仪测试了树脂浇铸体损耗因子,得到树脂体系的玻璃化转变温度,加入5份HEMAP后树脂体系的Tg从120.9℃提高到122℃。     

含磷低聚醚的合成及聚氨酯阻燃发泡材料的制备

以甲基亚磷酸二甲脂合成了羟基封端的含磷低聚醚,并用邻苯二甲酸酐吡啶法测定了羟值,磷钼蓝法测定了磷含量,凝胶色谱法对其分子最进行了测定,采用红外对其结构进行了表征。并以此制备了阻燃聚氨酯发泡材料,研究了发泡材料的阻燃性能。结果表明,这种含磷的低聚醚能够有效提高聚氯酯泡沫的阻燃性能,且具有较好的水解稳定性。     

含磷阻燃改性水性聚氨酯的合成及性能研究

采用2,4-甲苯二异氰酸酯、聚丙二醇、2,2-二羟甲基丙酸和10-(2,5-二羟基苯基)-10-氢-9-氧杂-10-磷杂菲-10-氧化物(ODOPB)制备了阻燃型水性聚氨酯(FR-WPU),讨论了ODOPB用量对FR-WP U及其胶膜性能的影响.结果表明,随着ODOP B用量增加,FR-WP U胶膜的极限氧指数先升后降...