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41.
岩石微观结构特征研究对非常规油气藏的演化规律、油气赋存状态、运移方式、渗流特征等基础地质问题研究具有重要的科学意义.利用CT 扫描技术对油砂、致密砂岩和页岩样品微观结构表征研究,并对比了常规测试方法与CT扫描表征技术的差异性. 对比CT扫描法和筛分法测试油砂矿物的粒度分布,两者结果十分接近,矿物颗粒大小分布总体趋势上差异小,但小于96μm的颗粒矿物分布差异性稍大.CT扫描结果显示致密砂岩样品的裂缝比较发育,还发育溶蚀孔隙. 由于测试方法和样品大小的差异性,CT扫描获得的孔隙度略大于氦气法孔隙度.微米CT 扫描可以表征页岩的层理发育情况,但无法表征内部的微观孔隙结构.与常规测试方法相比,纳米CT 扫描表征页岩中有机质和黄铁矿的含量等方面准确性好,但孔隙度测试结果偏小.纳米CT分辨率还不能完全满足表征页岩的微观孔隙结构的要求,同时有机质和孔隙的灰度值差异较小,两者区分难度大,因此纳米CT还无法完全准确表征页岩微观孔隙结构. 相似文献
42.
以五甲基茂基三苄氧基钛［Ｃｐ＊ Ｔｉ（ＯＢｚ）３］ 和甲基铝氧烷（ ＭＡＯ） 组成的催化体用本体法合成出苯乙烯 乙烯共聚物Ｐｏｌｙ（Ｓ ｃｏ Ｅ） ．考察了共聚温度,共聚时间,Ａｌ／Ｔｉ 摩尔比,主催化剂浓度［Ｔｉ］ 等条件对共聚反应的影响．共聚产物经沸丁酮,沸四氢呋喃（ＴＨＦ） 连续抽提分离,发现共聚物主要存在于ＴＨＦ 可溶级分中．可溶级分经ＤＳＣ,１３Ｃ ＮＭＲ,ＷＡＸＤ,ＤＭＡ 等手段分析,证明苯乙烯 乙烯共聚物为具有单一玻璃化转变温度（ Ｔｇ） 无熔融温度的无规共聚物,显示弹性体的粘弹性行为． 相似文献
43.
三苦味酸根·2,2'-二硫代二(N-氧化吡啶)合稀土(Ⅲ) 配合物的合成、表征及其抗肿瘤活性研究 总被引：4，自引：0，他引：4
据文献报导,2,2′－二硫代二（N－氧化吡啶）（简称配体L）不仅可以用在农药中抵抗生物疾病^[1],而且有着广泛的抗菌作用^[2]。由于稀土元素具有特殊的药理作用^[3,4],它与配体L形成的配合物,可能表现出更特殊的生理活性。因此,我们合成六种稀土苦味酸盐与2,2′－二硫代二（N－氧化吡啶）的配合物,并对配体及配合物的抗菌活性进行了测试。结果表明,配合物对L1210,HL－60人白血病细胞均有优于配体自身的抗肿瘤活性,其中Eu配合物对于HL－60细胞,La、Eu、Er配合物对于L1210细胞均有较强的杀伤能力,值得进一步做体内抗癌筛选。 相似文献
44.
45.
《International Journal of Polymer Analysis and Characterization》2012,17(2):171-184
Abstract Piperazine-modified fatty amide (PMF) was prepared from N,N-bis(2 hydroxy ethyl) linseed oil fatty amide and piperazine through condensation polymerization. It was further cured with butylated melamine formaldehyde in different phr (parts per hundred part of resin) (PMF-BMF). PMF and PMF-BMF systems were subjected to spectroscopic analysis to ascertain their structure and curing scheme. Thermal studies and curing behavior of these resins were carried out by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-mechanical performance and chemical resistance of PMF-BMF coatings were evaluated by standard methods. The effect of BMF content and curing temperature (ambient and elevated) on aforementioned coating properties was also investigated. It was found that PMF resin with 80 phr BMF cured at 120°C showed the best performance among all compositions. 相似文献
46.
《International Journal of Polymer Analysis and Characterization》2012,17(6):540-550
Abstract Polyamide (PA-10, 6) with long alkane segments between amide groups was synthesized using sebacic acid and paradiaminobenzene. Organoclay was incorporated into the polyamide through the extrusion process. The structural characterizations, thermal properties, and molar mass of the polyamide nanocomposites were determined using X-ray diffraction, thermogravimetry (TG), and Fourier transform-infrared (FT-IR) spectroscopy, respectively. Tensile strength and Young's modulus of these polymers were measured using a Universal Test Instrument. FT-IR confirmed the presence of organics in the modified clay product. Wide-angle X-ray diffraction results indicated that the nanoclay platelets were agglomerated in the polyamide matrix. Mechanical behavior and degradation kinetics of the polyamide nanocomposites are reported and discussed. 相似文献
47.
《International Journal of Polymer Analysis and Characterization》2012,17(3):137-146
Novel “green” polymer composites were successfully synthesized from pine needles and a phenolic matrix by compression molding technique. Various weight contents (10%, 20%, 30%, and 40%) of the pine needles were incorporated in the polymer matrix. Reinforcing of the polymer matrix with pine needles was done in the form of short fibers 3 mm in length. The effect of the fiber weight contents on the mechanical properties of the polymer was investigated. Thermal analysis (TGA/DTA/DTG) and scanning electron microscopy (SEM) were used to study the thermal stability and morphology of the composite systems respectively. 相似文献
48.
《International Journal of Polymer Analysis and Characterization》2012,17(2):173-184
Abstract Supercritical fluid chromatography (SFC) utilizes fluids or mixtures of fluids above their critical temperature and critical pressure which exhibit greater solvating properties with simultaneously reduced viscosities and higher diffusion coefficients compared with their liquid state; supercritical fluids, thus, offer new possibilities for characterizing polymers. The three modes of liquid chromatography are applied in the analysis of polystyrenes, using supercritical fluids (mixtures of dichloromethane with carbon dioxide) in each mode: adsorption chromatography for the separation of oligomers, size exclusion chromatography for the determination of molar mass distribution, and adsorption chromatography at critical conditions for the characterization of functionality type distribution. Advantages and disadvantages of size exclusion chromatography with fluids in their supercritical, subcritical and liquid phase are discussed with the system polystyrene in dichloromethane. 相似文献
49.
《International Journal of Polymer Analysis and Characterization》2012,17(3):305-321
Abstract This paper deals with the characterization of star-branched model copolymers. The polymer branches are composed of PMMA/PtBuA di-block copolymers of poly(methyl methacrylate) and poly(tert-butylacrylate) with well-controlled chemical composition and structure (very low polydispersity). When these copolymer branches are chemically coupled, they produce star-branched copolymers with various numbers of branches. Number-average molecular weights Mn of stars and branches were used to calculate the number of branches of the star-branched copolymers. In order to determine the real structure of the star-branched copolymers, we have measured the branching parameter g' and tested several hypothesis on the relationship which links the number of branches to the branching parameter g. The value of the exponent of the g/g' relationship, which characterizes the type of branching, was determined at several conditions. Values were dependent on the branching relationship, however, it was not possible to find an exponent value of 0.5, corresponding to pure star-branched molecules. We could not conclude whether or not the technique of multidetection GPC was not accurate enough to obtain this kind of information or if the studied star-branched copolymers had a complex structure, more complicated than a simple star. Excellent agreement was found between light scattering values and from viscometry with universal calibration. These results demonstrate excellent performance for universal calibration, even for highly branched polymers with unusual viscometric behavior. 相似文献
50.
《International Journal of Polymer Analysis and Characterization》2012,17(4):379-393
Abstract A series of ethylene(E)/propylene(P) copolymers covering a large range of compositions is obtained by a new solution copolymerization process. The catalyst system consists of a high-activity, high-regioselectivity and high-stereospecificity Ti complex supported on MgCl2. The cocatalyst is triethylaluminum treated with diphenyldimethoxysilane. The polymers are studied by 13C NMR, and the E- and P-centered triads analyzed via the computer-assisted analytical approach. Through a systematic analysis, one can determine the minimum number of components that are needed to fit the data. Each component would correspond to a family of similar catalytic sites. The reactivity ratios (rE and rP ) of each family of active sites and the component weight factor (related to the catalytic activity) are also determined. 相似文献