Ti(C,N)基金属陶瓷中陶瓷相芯/壳组织的观察与分析

用ＸＲＤ，ＳＥＭ，ＴＥＭ和ＨＲＥＭ观察、分析和方法研究了Ｔｉ（Ｃ，Ｎ）基金属陶瓷中陶瓷相的芯、壳组织。结果表明，在ＳＥＭ，ＴＦＭ观察中，芯、壳之间存在相界面，而ＨＲＥＭ观察显示陶瓷相的芯／壳组织具有连续相同的点阵结构。     

聚丙烯酰胺中丙烯酰胺的测定

聚丙烯酰胺中丙烯酰胺的测定董占先，张晓波，孙路ＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＡＣＲＹＬＡＭＩＤＥＩＮＰＯＬＹＡＣＲＹＬＡＭＩＤＥ１前言聚丙烯酰胺作为絮凝剂在供水和食品工业中得到广泛的应用，由于丙烯酰胺单体有毒，所以分析聚合物中单体含量具有很重要的意义...     

MDF水泥抗弯强度与大孔尺寸和孔隙率的关系

采用压汞仪、氦比重仪和ＳＴＥＭ等仪器研究了ＭＤＦ水泥抗弯强度与大孔尺寸和孔隙率的关系。实验结果表明，抗弯强度与孔隙率有良好的相关性，孔隙率降低，抗弯强度明显增高。抗弯强度与大孔尺寸没有明显的相关性，Ｋｅｎｄａｌｌ修正的Ｇｒｉｌｆｉｔｈ方程不适用于ＭＤＦ水泥。     

聚丙烯/玻璃纤维的界面改性研究(Ⅳ)--玻璃纤维增强聚丙烯复合材料的界面结构特征

研制高性能的玻璃纤维增强聚丙烯复合材料的关键是提高非极性的聚丙烯和极性的玻璃纤维的界面粘结强度。文章运用溶剂抽提ＦＴ－ＩＲ、ＤＳＣ、ＳＥＭ等分析测试手段对ＦＲＰＰ的理化性能进行了表征,提出玻璃纤维增强聚丙烯复合材料体系的最突出的界面特征是界面剂接枝物与玻璃纤维的相互作用和界面剂接枝物与聚丙烯基体树脂的共结晶。     

辐射增强共混物相容性的研究

研究了在多官能团单体存在下，辐射对ＰＰ／ＬＤＰＥ，ＰＳ／ＥＰＤＭ等不相容共混体系的敏化效应，并用ＳＥＭ，ＤＳＣ以及动态力学性能等对其进行了表征。结果表明，辐射敏化界在反应的方法是增强不相容聚合物共混物相界面粘接和改善其相容性的一种有效途径。     

螺旋霉素的油／水界面循环伏安法测定

螺旋霉素的油／水界面循环伏安法测定韩玉洁，杨文友，徐忠ＣＹＣＬＩＣＶＯＬＴＡＭＥＴＲＹＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＳＰＡＮＭＹＣＩＮＡＴＷＡＴＥＲＬＯＩＬＩＮＴＥＲＦＡＣＥＳ１前言油／水界面循环伏安法是近年来发展起来的一种新的电化学分析方法。并且已...     

混合材料与水泥浆体间界面的形貌特征

用ＳＥＭ和ＥＤＳ研究了矿渣，钢渣，粉煤灰，石灰石，大理石和石英等混合材料和水泥浆体间所形成界面的形貌特征，讨论了水泥水化初期和后期混合材料颗粒界面状态的模型。     

从断裂模式分析CFRP的界面性质

从炭纤维增强树脂基复合材料的剪切断裂模式出发，讨论了炭纤维经瞬时高温空气氧化法和气液双效法表面处理后，ＣＦＲＰ的断裂模式与界面性质的关系。证明气液双效法表面处理炭法纤维所制ＣＦＲＰ与空气氧化法表面处理后的ＣＦＲＰ相比不仅增加了ＣＦＲＰ界面粘结强度，其ＩＬＳＳ可能达到了９０－１１０ＭＰａ，而且增加了ＣＦＲＰ的断裂韧性。     

PAT测孔技术研究及其在MDF水泥中的应用

探讨了正电子湮没测孔技术及其在水泥材料中的应用，并与水银压入法测孔技术进行了对比实验，认为ＰＡＴ能对水泥材料中孔结构及其发展过程的变化规律进行描述，适用于其它测孔法无法解决了微孔结构的分析，可与这些方法起到相互补充的作用，利用ＰＡＴ对ＭＤＦ水泥材料的研究表明，它可揭示这种材料中相间界面作用增加的效应，并能对聚合物在材料制备过程中的主物理化学作用进行解释。     

无宏观缺陷水泥基复合材料的水敏特性及其破坏机理研究

无宏观缺陷（ＭＤＦ）水泥基复合材料的水敏性问题是这种高抗折强度瓣致命弱点。本工作研究了高铝水泥／聚乙烯醇基ＭＤＦ复合材料吸温后对其物理力学性能和生观结构的影响。结果表明,ＭＤＦ复合材料在１００％相对湿度中的吸湿过程初始受扩散动力学控制,吸湿量取决于聚合物的含量,水透过复合材料的扩散系数为１０＾０８ｃｍ＾２／ｓ数量级;其在水中的强度随浸水时间的延长连续下降,同时伴有不可忽视的一膨胀。ＭＤＦ复合材料的     

Microstructural and Microchemical Characterization of a Calcium Aluminate—Polymer Composite (MDF Cement)

The microstructure of a macrodefect-free (MDF) cement has been characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and high-resolution electron microscopy (HREM). The microchemistry of ultramicrotomed samples has been studied by energy dispersive spectrometry (EDS) and parallel electron energy loss spectrometry (PEELS). MDF cement consists of CaAl₂O₄ and CaAl₄O₇ grains randomly distributed in a polymer matrix. The ceramic/polymer interface contains an amorphous interphase inside of which are distributed very fine crystallites of the metastable hydration product Ca₂Al₂O₅·8H₂O. PEELS analyses of the interphase revealed the presence of carbon, indicating that Ca₂Al₂O₅·8H₂O was most likely stabilized by the intercalation of polymeric chains into its basal interlayers. The polymer phase preferably cross-links with Al. In situ environmental cell electron microscopy showed that moisture uptake of MDF cements occurred by polymer swelling and interphase dissolution. The role of the interfacial interphase in dry and wet mechanical properties is discussed.     

Binder Distribution in Macro-Defect-Free Cements: Relation between Percolative Properties and Moisture Absorption Kinetics

Macro-defect-free (MDF) cement is fabricated from a calcium aluminate cement and a poly(vinyl alcohol-acetate) (PVA) copolymer. For the composites studied, it was determined that the interphase regions comprised 63 voi % of the total binder content, while the bulk PVA regions comprised 37 vol% of this phase. Mercury intrusion porosimetry showed that a bimodal pore size distribution developed as binder was removed in increasing amounts from heat-treated samples. Larger pores with a characteristic diameter above 30 nm resulted from the removal of bulk PVA, whereas smaller pores approximately 5 nm in size resulted from the removal of water and PVA from the interphase regions. Simulation results obtained from a hard-core/soft-shell continuum percolation model of the MDF microstructure indicate that both the bulk PVA and interphase regions form percolative pathways through the system. Dramatic changes in both moisture absorption kinetics and flexural strength were observed only when a percolative network of larger pores was present in these composites. Hence, the bulk polymer regions are the dominant transport pathway for moisture in MDF cement. Based on this knowledge, processing guidelines have been developed to improve the moisture resistance of these materials.     

高贝利特水泥混凝土的断裂韧性

为研究高贝利特水泥混凝土的断裂性能,通过三点弯曲梁试验,比较了高贝利特水泥混凝土与硅酸盐混凝土的双K断裂参数。结合载荷–裂口张开位移曲线分析,探讨了高贝利特水泥混凝土的断裂能。结果表明：高贝利特水泥混凝土载荷–裂口张开位移曲线下覆盖的面积大于硅酸盐水泥混凝土,混凝土对载荷能量有较高的吸收能力,断裂能大,断裂韧度大;高贝利特水泥混凝土的起裂韧度和失稳韧度分别是硅酸盐水泥混凝土的1.17倍和1.24倍。高贝利特水泥混凝土的断裂性能优于硅酸盐水泥混凝土的。     

水泥净浆微观结构断裂破坏过程的三维模拟(英文)

在微观层次上研究了水泥净浆的断裂破坏过程,提出了两种模拟水泥净浆微观结构断裂破坏过程的方案,即:格构模型HymLat方案和通用格构模型ImgLat方案。在HymLat方案中,被分析的水泥净浆微观结构只能是由球形颗粒组成,但在ImgLat方案中,研究对象不局限于由球形颗粒组成的微观结构,所有能由像素表达的微观结构都能采用ImgLat方案进行分析。这两种方案的共同之处是水泥净浆的微观结构均由HYMOSTRUC3D模型模拟得到,而断裂破坏过程都使用GLAK(Generalized Lattice Analysis Kernel)通用格构模型分析核心代码模拟仿真。对这两种方案在通用性和计算效率方面的差异进行了比较。     

聚合物改性水泥基材料的机理研究进展

综述了近年来聚合物改性水泥基材料(polymer modified cement based materials,PMCBM)改性机理方面的国内外研究进展.从理论角度对PMCBC进行了归纳与总结,重点从4个方面探讨了聚合物改性水泥基材料的改性机理:聚合物对水泥水化过程的影响存在物理作用和化学作用;聚合物对微观结构的主要影响是乳胶粒子的分散和聚合物薄膜的形成;从孔洞结构看,聚合物改变了水泥基材料的孔径分布、特征孔径、平均孔径、最可几孔径、孔隙率等,提高了材料的内聚强度;从聚合物自身结构来看,聚合物的链结构和聚集态结构直接影响水泥基材料的性能.     

Physicomechanical properties of irradiated SBR latex polymer‐modified cement mortar composites

This study investigated the effect of styrene–butadiene‐rubber (SBR) latex/cement ratio as well as γ‐irradiation dose on physicomechanical properties of cement mortar. Specimens were prepared with a different SBR/cement mass ratio of 2.5, 5, 10, 15, and 20. Two curing methods were used: wet cure and dry cure. The best specimens were irradiated to doses of 10, 30, and 50 kGy. The compressive strength, total porosity, and bulk density were studied. The result indicated that the compressive strength, total porosity, and the bulk densities of the composites decrease with increase in the polymer cement ratios. In addition, it was observed that the compressive strength of irradiated polymer‐modified cement mortar composites was improved with the increase in the γ‐irradiation dose, and the compressive strength of mix‐cured samples was higher than those wet‐cured samples at any irradiation dose. X‐ray diffraction, thermogravimetric analysis, acid attack, and microstructure of SBR‐modified cement mortar were characterized. J. VINYL ADDIT. TECHNOL., 26:144–154, 2020. © 2019 Society of Plastics Engineers     

Experimental study on properties of polymer-modified cement mortars with silica fume

This paper discussed the flexural and the compressive strengths of polyacrylic ester (PAE) emulsion and silica fume (SF)-modified mortar. The chloride ion permeability in cement mortar and the interfacial microhardness between aggregates and matrix were measured. The chemical reactions between polymer and cement-hydrated product were investigated by the infrared spectral technology. The results show that the decrease of porosity and increase of density of cement mortars can be achieved by the pozzolanic effect of SF, the water-reducing and -filling effect of polymer. Lower porosity and higher density can give cement mortars such properties as higher flexural and compressive strength, higher microhardness value in interfacial zone and lower effective diffusion coefficient of chloride ion in matrix.     

石膏掺量对高阿利特水泥防腐抗渗性能的影响研究

研究了石膏掺量对高阿利特水泥抗海水侵蚀和抗渗性能的影响,并与普通水泥进行了比较。利用XRD、SEM—EDS等测试方法对水泥水化产物的物相组成和形貌进行分析、观察;用压汞法对水泥硬化浆体的孔结构进行了分析。结果表明,石膏掺量对高阿利特水泥硬化浆体的致密性有较大影响,进而影响水泥砂浆的抗海水侵蚀性能,石膏的适宜掺量为5％,在此掺量下高阿利特水泥的抗蚀系数达1．01,而普通水泥的抗蚀系数仅为0．87,高阿利特水泥的有害孔较少,总孔隙率较低,抗渗性能得到较大改善。