特稠油乳化降黏机理研究

研究了胜利油田罗家高硫特稠油的黏度及其极性四组分、有机杂原子、金属元素的关联。结果表明,该稠油的高黏度主要与三个因素有关：（1） 含有高分子量的胶质和沥青质组分;（2） 硫的质量分数很高;（3） 金属元素V、Fe、Ni形成配位络合物增加了沥青质的内聚力。同时考察了所筛选的降黏剂的效果,降黏剂明显降低了油水界面张力,使得稠油的黏度降低。比较了添加降黏剂前后沥青质的电子探针照片的变化,推测降黏剂分子借助强的形成氢键的能力和渗透、分散作用进入沥青质片状分子之间,破坏了沥青质分子平面重叠的聚集体,使聚集结构变得疏松,表明聚集有序性降低是稠油降黏的主要机理。     

用电子探针测定铝合金在定向凝固过程中的溶质分配系数

用电子探针测定了铝合金中Ａｌ－１．３５％Ｃｕ和Ａｌ－０．２５％Ｃｒ在定向凝固过程中凝固界面处的溶质分配系数。结果表明：液相区的Ｃｕ含量随离开界面的距离呈指数衰减,而固相区的则呈线性衰减。液固界面层厚度约在５－７μｍ范围内。用电子探     

Interdiffusion at the interface between poly(vinylpyrrolidone) and epoxy

Electron microprobe analysis (EMP) was used to study interdiffusion in bilayer films of thermoplastic poly(vinylpyrrolidone) (PVP) and a thermoset epoxy. The bilayer films were prepared by casting a stoichiometric mixture of the uncured diglycidyl ether of bisphenol A epoxy (DGEBA) and 4,4′-diaminodiphenylsulfone (DDS) on the PVP film and then curing the system in a two-step process under a nitrogen atmosphere. For the EMP studies, the sulfur signal was used as a probe for DDS, while the nitrogen signal served as a probe for both DDS and PVP. The addition of brominated DGEBA to the conventional DGEBA in a 1: 1 weight ratio allowed the bromine signal to be used as a probe for the epoxy phase. It was found that the interfacial thickness was much larger for the film prepared from low molecular weight PVP than that from high molecular weight PVP. Interdiffusion was suppressed when the initial cure temperature in the two-step cure cycle was 130°C compared to 170°C, in which the first stage of the cure reaction dominated the interdiffusion process. More importantly, it was demonstrated that the diffusion front of the curing agent was located closer to the thermoplastic polymer phase as compared to that of the thermoset polymer in the interface region. This tendency was more significant in the system with the larger interfacial thickness. These results have important consequences on interphase structures and properties. They suggest that crosslinking of the epoxy in the interphase may be suppressed because of an insufficient amount of curing agent and that the not-fully-reacted curing agent in the PVP phase may act to plasticize this phase. © 1997 John Wiley & Sons, Inc.     

富铁硅钛铈矿的晶体化学

通过电子探针分析和晶体结构测定, 证明四川冕宁碱性花岗岩中的天然非变生铁硅钛铈矿, 以富含铁、稀土和铌为特征, FeO(全铁)质量分数为10.97%～11.59%, Ce2O3 变化范围为23%～25%, Nb2O5为1.53%～2.10%;化学式中存在A型和(B C)型阳离子缺失; 具有C2/m空间群(R=2.41%); 晶胞参数为: a=1.3456(3) nm, b=0.57280(10) nm, c=1.1083(2) nm, β=100.60(3)°, V=0.8397(3) nm3, Z=2. 富铁硅钛铈矿的晶体结构由2种层组成, 一是由Si2O7 基团和B-八面体构成的层, 一是由C-八面体层构成的层; 2种层均平行ab平面, 沿c轴交替排列构成三维格架. 稀土离子位于双硅酸根和八面体层之间, 形成(8 3)配位的A(1)多面体和10配位的A(2)多面体. Fe和Ti呈部分有序分布于B, C(1), C(2A) 和C(2B)位置中.     

Laser microprobe mass spectrometry (LMMS) of intracrystalline crown ether and cryptand complexes in layer silicates

Laser microprobe mass spectrometry (LMMS) allows the characterisation of organic inclusions in mineral materials. The complexes are detected as cationized or protonated molecules, arising from the intact desorption or from recombination within the laser generated microplasma. The results obtained sustain the interpretation from other techniques concerning the nature of the cation-ligand association and the proton exchange of the cryptand for acidic Cu²⁺-ions.     

多孔硅纵向分辨拉曼及光致发光研究

运用高灵敏度的共焦显微拉曼系统研究了多孔硅在纵向的拉曼效应和光致发光的性质。研究结果表明多孔硅在形成的初期和后期的反应机制不相同。反应初期,外表面的颗粒尺寸比内表面的大,而经过长时间刻蚀而获得的多孔硅,其外表面颗粒尺寸比内表面的小。我们认为反应的初期主要受表面不均匀电场的影响,而随着表面多孔层的增厚和颗粒的细化,刻蚀反应逐渐变成受传质过程和量子尺寸约束的控制。     

Assessment of local analysis by fourier transform laser microprobe mass spectrometry with external ion source

Laser microprobe mass spectrometry (LMMS) is a technique for local analysis of inorganic and organic constituents in the m range. This paper will focus on selected applications. First of all, element detection is illustrated by data from a 50-nm TiW layer on silicon and by the detection of residual Cr on HPLC column packing material. Speciation capabilities of LMMS are demonstrated on pure substances and on a coated neo-ceramic. Finally, the feasibility of organic analysis is shown in the case of a biologically active compound and dyed cloth fibres.     

Detection and visualisation of elemental components in various ambient species by synchrotron microbeam technique

This study introduces the application of the synchrotron radiation induced X-ray fluorescence (SR-XRF) microprobe installed at the Super Photon ring-8 GeV (SPring-8), which is the world's largest third-generation synchrotron radiation facility, to the specification of chemical properties of various atmospheric samples. The combination of visual elemental mapping and XRF spectral analyses allows for the interpretation of the nature and composition of individual particles. Individually collected droplets by the replication technique were also irradiated by X-ray microbeam to carry out visual reconstruction of elemental maps for their multiple components. The multielemental peaks corresponding to X-ray energy were also successfully resolved. Because the chemical contents of solute for individual droplets can be definitely clarified in this study, we can describe the mechanisms involved in droplet formation and pollutant scavenging. The point analysis of sand dust collected from the local desert in China confirmed that the fine fragments of sand, which may be lifted and transported over a long distance, are considerably inhomogeneous in elemental component.