大气吸收系数的研究与应用

定义了大气吸收系数的概念．通过试验及理论分析．得出我国各地区大气吸收系数推荐值，并时体育场场地照明照皮计算进行修正。     

抓消防 保平安构建和谐生态民俗村

崔西沟村地处关中平原,位于陕西省杨凌农业示范区西北方向,是远近闻名的生态民俗村。全村现有118户、498人,人均土地1亩,2006年人均纯收入3800元。常言道:“贼偷偷一把,火烧当日穷”。几年前的一个夏收时节,邻村一场大火几乎把刚收获的近百亩小麦全部烧光,崔西沟村村民至今记忆犹新。可是过去,家家户户都一门心思想挣钱,村民的消防意     

吸湿发热聚丙烯腈纤维的性能研究

采用傅立叶变换红外光谱、扫描电子显微镜、X射线衍射仪和热重分析仪对交联改性制备的吸湿发热聚丙烯腈(PAN)纤维的吸放湿性能进行表征,与普通PAN纤维及进口吸湿发热PAN纤维进行对比。结果表明:交联改性制备的吸湿发热PAN纤维红外光谱出现了较强的羟基峰和羧酸盐的伸缩振动峰,相比普通PAN纤维,表面沟槽加深、粗糙度增加,在100℃内失重率达17.17%,热分解温度提高近70℃,结晶度大幅下降,力学性能降低;交联改性PAN纤维的吸放湿性能较普通PAN纤维大幅度提高,并高于进口吸湿发热PAN纤维,其平衡回潮率约30%,吸湿积分热达155 J/g。     

含N,N-二甲基甲酰胺废水的处理方法研究

N,N-二甲基甲酰胺(DMF)作为一种性能优良的有机溶剂被广泛运用于农药医药等行业作为中间体及气体吸收剂,化工废水中含有大量DMF,具有毒性高、稳定性强、难生物降解等特点。近年来废水中的DMF问题已成为国内外研究的重点和难点,本文针对含DMF的化工废水处理方法进行了综述,主要从物理法、化学法以及生物法等工艺的研究概括及原理介绍,指出了含DMF废水的主要问题并提出了未来的发展方向。     

碱性染料在贵金属催化光度法中的应用

近年来,传统光度分析中常用的碱性染料在贵金属的催化光度法中得到了普遍应用,该方法操作简便,试剂易得,对责金属测定灵敏度很高,是一种具有较大发展空间和应用前景的分析方法.通过介绍碱性染料催化光度法测定责金属的方法原理及操作方法,综述了目前已建立并用于测定贵金属的多种碱性染料催化体系及其应用现状,总结方法的优点及存在的不足...     

Gas-particle partitioning of polychlorinated dibenzo-p-dioxins and dibenzofurans in the sintering process

The distribution of seventeen gaseous and particle-bound 2,3,7,8-substituted chlorinated PCDD/Fs in the flue gas of different windboxes of the sintering machine was analyzed.The influence of temperature change on the PCDD/Fs emission from the sintering process and the formation mechanism of PCDD/Fs were discussed.The result has shown that among the seventeen gaseous and particle-bound PCDD/Fs in the flue gas of different windboxes,furans occupied the major place.The proportion of the gaseous PCDD/Fs in most windboxes is from 40% to 60%.The change tendencies of the concentration of both the gaseous and particle-bound PCDD/Fs were similar,with a higher level at the end of the sintering bed.The PCDD/Fs concentration’s change tendency in the windbox was very consistent with the change of temperature of the flue gas in the windboxes.More than 60% PCDD/Fs of the total PCDD/Fs emission amount was emitted at the end of the sintering bed.Only this part of the waste gas accounted for 12% of the total waste gas volume.     

Numerical simulation of tube profile growth during spray forming process

Spray forming is a new type of metal material forming process,which can produce metal blanks such as billet,tube,plate etc.A mathematical model has been developed to forecast the shape evolution of tube billets during the spray forming process.The atomizer mass flux as,radial distribution coefficient bs,draw velocity and diameter of mandrel were considered in this model and the influence of different parameters such as metal flowrate,draw velocity of mandrel,diameter of mandrel on the tube’s shape change were simulated and analyzed in this paper.The simulation results obtained from this model can be provided to engineers as reference.     

Status and development of mineral wool made from molten blast furnace slag

This study describes the characteristics of mineral wool and its applications,and also introduces the traditional process of mineral wool made from molten blast furnace(BF) slag.Compared with high energy consumption of the traditional process,the production of mineral wool by using molten BF slag will be able to take full advantage of the sensible heat of molten slag,and also reduce production costs.However,there are also further issues to resolve such as how to obtain the required amount of molten BF slag and how to make it homogeneous.Based on the physical and chemical properties of the molten BF slag,the investigation into the relationship between temperature and viscosity under different acidity coefficients of the slag and silicon mixture was conducted.Combined with the crystallization and phase diagram of slag wool,its heat resistance,water resistance,durability and corrosion resistance were analyzed.Finally,trends of the technology development are proposed.     

Research on the trajectory of non-metal inclusions with the flow in the mold during the solidification of continuous casting slabs

By means of the numerical simulation method,the mathematical model of inclusions movement in the mold is established under the condition of austenitic and ferritic stainless steel slab production.According to the simulation results,the main zones for inclusion particles accumulation were found and many factors that affected floating-up probability of inclusion particles were identified.These factors include the inclusion particle size,the casting speed and the slab width,etc.It is believed that the inclusion particle size is the key one among these factors.     

Microstructure and micro-hardness of the Inconel 718 superalloy coating prepared by cold gas dynamic spraying

Inconel 718 superalloy coating was prepared on a martensitic steel substrate by cold gas dynamic spraying (CGDS).Microstructure and micro-hardness of the coating were characterized by means of scanning electronic microscope (SEM),energy dispersive spectrometer (EDS),and micro-hardness and nano-indentation tests.The results have indicated that the coating’s thickness can reach more than 300 μm,and there exists a good interfacial cohesion between the coating and the substrate.The quantity and size of the defects at the bottom,middle and top areas increase gradually.There is no significant change to the original microstructure of the Inconel 718 superalloy particle after the process of CGDS;and an obvious torsional deformation on the particle’s profile is produced while little deformation at the center part occurs.The micro-hardness of the coating at the bottom,middle and top areas decreases in turn.Compared with the bottom area,the micro-hardness of the middle and top areas decreases by about 10% and 21%,respectively.The nano-hardness of the coating is much lower than the original particle,which decreases by about 13.5% at the bottom area and 28% at the top area,respectively.The distribution of micro-defects is an important factor to the micro-hardness of the coating.