水中硫化物对20A腐蚀行为的研究

采用重量法、电化学法、表面分析法、研究了水中硫化物对２０Ａ的腐蚀行为，还探讨了硫化物对２０Ａ腐蚀的关机理，研究结果表明，水中硫化物对２０Ａ有加速作用。     

异丙烯膦酸-丙烯酸共聚物对A_3碳钢的缓蚀行为

以异丙烯膦酸－丙烯酸共聚物（ＰＩＰＡＡ）为缓蚀剂，探讨了ＰＩＰＡＡ的浓度、Ｃａ２＋浓度、Ｃｌ－浓度和ｐＨ值对Ａ３碳钢缓蚀行为的影响利用极化曲线，证实了ＰＩＰＡＡ的缓蚀作用主要是在金属铁表面形成保护膜，从而抑制了电化学腐蚀反应     

水中硫化物对20A腐蚀行为的研究

采用重量法、电化学法、表面分析法，研究了水中硫化物对２０Ａ的腐蚀行为，还探讨了硫化物对２０Ａ腐蚀的有关机理研究结果表明，水中硫化物对２０Ａ有加速作用     

R—SMA增容PA6／PP共混物的形态结构与流变行为

采用Ｒ－ＳＭＡ为增容剂制备ＰＡ６／ＰＰ共混物，讨论了Ｒ－ＳＭＡ对共混物形态结构和流变行为的影响。     

HAN-TEAN-H_2O 三元体系的相变及其相图

用ＤＳＣ研究了ＨＡＮ－ＴＥＡＮ－Ｈ２Ｏ三元体系的低温热行为，建立了该体系低温下相变与组分关系的相图。考察了玻璃化转化温度随ＨＡＮ／ＴＥＡＮ比例的变化规律。发现了三元体系的溶液性质在ＨＡＮ－ＴＥＡＮ比率较大时，与ＨＡＮ－Ｈ２Ｏ二元体系相似，而在ＨＡＮ／ＴＥＡＮ比率较小时，则与ＴＥＡＮ－Ｈ２Ｏ二元体系相似。     

SAN对PVC／CPE加工行为的影响

采用Ｂｒａｂｅｎｄｅｒ塑化仪和双辊开炼机，研究了几种刚性有机填料ＳＡＮ（苯乙烯和丙烯腈的共聚物）对ＰＶＣ／ＣＰＥ（聚氯乙烯／氯化聚乙烯）共混体加工行为及力学性能的影响。实验表明：这几种ＳＡＮ均有缩短ＰＶＣ／ＣＰＥ塑化时间，改善熔融塑化行为的效能，但不同流动性的ＳＡＮ作用有所差异。还证实了不同加工方法的改性效果不尽相同。     

接枝交联明胶的研究（Ⅱ）：具有亲水性与亲油性接枝支链的交联明胶的合成…

首次以ＡＰＳ－Ｎａ２Ｓ２Ｏ３为引发体系，实现了甲基丙烯酸甲酯与Ｇｅｌｘ－ｇ－ＰＭＡＡ的接枝共聚反应，研究了反应规律，以ＩＲ表征了产物的结构；得到两亲性接枝共聚交联明胶，并对此类接枝改性明胶在各种溶剂中的溶胀行为作了初步的研究。     

氧化钕填充尼龙6的结晶行为

利用示差扫描量热仪（ＤＳＣ）研究了氧化钕（Ｎｄ２Ｏ３）对尼龙６（ＰＡ６）等温结晶行为的影响。结果表明，Ｎｄ２Ｏ３在ＰＡ６体系中起到了异相成核作用，提高了ＰＡ６的晶体增长速率。     

SAN及MBS改性氯化聚氯乙烯的研究

研究了稳定体系、ＳＡＮ及ＭＢＳ对氯化聚氯乙烯共混物力学性能、耐热性及加工行为的影响。结果表明：采用钡／镉复合稳定体系可获得较好的综合性能；提高ＭＢＳ用量可以增加共混物的冲击强度和断裂伸长率，耐拉伸强度下降；ＳＡＮ用量增加，共混物的拉伸强度上升，而冲击强度和断裂伸长率下降，加入ＳＡＮ和ＭＢＳ。共混物的耐热性略有下降，但能改善共混物的辊上加工行为。     

5—Br—PADAP一阶导数光度法同时测定钴和镍的研究

本文研究了５－Ｂｒ－ＰＡＤＡＰ与钴，镍反应的导数行为，利用一阶导数光度法同时测定钴和镍的新方法。用所建立的方法对化学试剂中的钴和镍的含量进行了同时测定，结果令人满意。     

Linking laboratory data with pilot scale entrained flow coal gasification performance. Part 1: Laboratory characterisation

Pilot scale measurements play an important role in our understanding of the coal gasification process. To gain the most practical benefits from such testing it is important to have a good understanding of the fundamental processes that influence coal behaviour under industrial conditions. In this paper, a suite of Australian coals was characterised in detail at the laboratory scale and preliminary assessments made of their likely performance under practical entrained flow conditions. The same coals were then tested using a 5 MW_th pilot-scale entrained flow gasifier in Part 2. The resulting gasification dataset for a suite of coals at both laboratory and pilot scale provides a unique opportunity to quantify the links between laboratory gasification measurements and coal gasification behaviour under realistic conditions. This paper presents a characterisation of four Australian thermal coals in terms of their slag formation and flow behaviour, coal devolatilisation and reactivity properties, and their gasification conversion behaviour. This work provides the basis for a relative assessment of their potential for use in entrained flow gasification, and identifies possible performance issues which may need consideration for use in larger-scale gasification systems. The second paper discusses the pilot-scale gasification behaviour of these coals, and relates those data with those presented here.     

Fractography of biaxial tested Si3N4-specimens

The strength of ceramic materials is limited by flaws which are distributed in the volume or on the surface of the material. Commonly, fractographic investigations are performed after the strength tests to interpret the strength values.The relatively new Ball-on-Three Balls (B3B)-bending test applies a biaxial stress state (which is more searching for cracks than a uniaxial stress state) on the specimen. To identify typical fracture initiating flaws and to get a better understanding of the fracture behaviour of B3B-specimens a systematic fractographic investigation was performed on 260 silicon nitride specimens divided into batches with different surface qualities. It could be shown that in most cases (at least those in which origins could be clearly identified) surface or near surface located defects were responsible for failure. On specimens with poor surface qualities, surface defects were introduced through machining. On specimens with a better surface quality, volume defects, which were exposed on the surface by polishing, could be identified as fracture origins. In only a few cases defects in the bulk were fracture origins.     

Evidence for electron transfer of excited indigo dyes with both electron-acceptors and electron-donors

N,N'-Disubstituted indigo derivatives undergo a very efficient electron transfer reaction in their excited singlet state due to a low reduction potential (ca. ?0.6 V). The rate constant of the reaction is of the same order as that of a diffusion-controlled reaction, when the electron-donating molecules have an oxidation potential lower than 1.0 V.Surprisingly, the same dyes undergo a quenching of their singlet excited state by tetracyanoquinodimethane, a strong electron-accepting molecule. This unusual behaviour has been rationalized on the basis of their voltammetric curves. The effect of this phenomenon on the stability of these dyes is discussed on the basis of a self-quenching process.     

The Role of Crosslink Density in Influencing the Electrical Resistance Behaviour of Polymeric Coatings

Paint films used to protect metalic surfaces are commonly polymeric in nature. The extent of protection offered by film depends on many factors including the characteristic electrical resistance behaviou and its effect on impeding local electrochemical processes. In the present work a range of polymeric coatings have been produced with systematically varied crosslinked density using an ultra-violet light curing technique. Their electrical resistance behaviour in an environment of varying concentrations of KC1 electrolyte has been examined. It is demonstrated that there are signs of the beginnings of a mechanism changeover from “D-type” to “I-type” behaviour at higher levels of crosslink density thus giving some tenuous support to previously unproven hypotheses in this area.     

Ferroelastic mechanical behaviour of porous La0.6Sr0.4Co0.2Fe0.8O3−δ

The present study investigates the mechanical behaviour of ferroelastic La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ with porosity ranging from 0.9% to 26.1% under uniaxial compression at room temperature. Both dense and porous samples have ferroelastic domains and exhibit ferroelastic mechanical behaviour. The apparent modulus, compressive strength and critical stress of the material dramatically decrease with increasing porosity, exhibiting exponential relationships. Comparison of the mechanical behaviours of samples with similar porosity but different porous structures reveals that the ferroelastic mechanical behaviour depends not only on porosity but also structural factors such as pore size and distribution.     

Studies on thermal–oxidative degradation behaviours of raw natural rubber: PRI and thermogravimetry analysis

Abstract

Thermal–oxidative degradation behaviours of raw natural rubber (NR) have been investigated by using thermogravimetry analysis in inert and oxidative atmospheres and the plasticity retention index (PRI). The activation energy E_a, was calculated using Horowitz–Metzger and Coats–Redfern methods and compared with PRI. The E_a values obtained by each method were in good agreement with each other. The June samples are the least stable rubbers among the studied ones, whereas February samples exhibited the highest values of activation energy, therefore in agreement with the PRI behaviour, which indicates that the thermo-oxidative stability of the June samples are the poorest during the thermo-oxidative degradation reaction. Natural rubber is a product of biological origin, and thus these variations in the values of thermal behaviour and PRI might be related to the genetic differences and alterations of climatic conditions that act directly on the synthesis of non-rubber constituents, which are generally reflected in latex and rubber properties.     

天然气水合物浆体流变性与安全流动边界研究进展

水合物安全流动技术作为一种新型的天然气运输管理方法具有广阔的发展前景,本文在综述国内外天然气水合物安全流动研究的基础上,分析了管道流动天然气水合物生成机理、特点和对油气管道的不利影响以及现有水合物安全流动研究存在的问题,包括实验管道长度较短、着重流动规律的研究而缺乏对流动边界的拓展等。进而对国内外天然气水合物低剂量抑制剂(low dosage hydrate inhibitor,LDHI)在保障天然气水合物安全流动、拓展天然气水合物安全流动边界以及螺旋流携带研究进行了总结评述;随后提出了利用螺旋流悬浮输送技术保障天然气水合物安全流动、拓展流动边界的新型方法。结合实验结果分析表明:螺旋流动从宏观上改变水合物浆体流动特点、有效提高水合物浆液的输送浓度并可拓展水合物安全流动边界。     

槽式孔板的低含液率气液两相流测量特性

槽式孔板是一种新型气液两相流量传感器,目前尚未发现能够应用于槽式孔板的两相流压降相关式,结合空气/水两相流实验数据,比较了五类典型的标准节流元件两相流压降相关式对槽式孔板测量数据的计算结果,分析了这些相关式的适用范围和误差原因。基于不同的建模思想,综合考虑洛—马参数、介质压力、气相流量等参数的作用,建立了三种相对准确的槽式孔板两相流压降相关式,并将其应用于低含液率的凝析天然气计量技术研究,计算结果表明三种相关式均能达到工业计量的精度要求。     

基于图像动态纹理特征的气固流化床流型识别

准确识别流型是气固流化床二相流参数检测的重要内容,文中提出一种基于图像光流法和动态纹理特征相 结合的气固流化床流型识别的新方法.实验是在气固流化床二相流实验系统上利用高速摄影系统获取流型图像.流型图像分别为鼓泡床,节涌床,湍动床,快速流化床,稀相输送等5种典型流型.首先对获取的不同流型图像分别进行去噪和对比度拉伸...