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981.
The current research was performed on four petrologic end members samples from Syncrude's North Mine collected in 2012 (NM12), i.e. marine clay (MC), marine sand (MS), estuarine clay (EC), and estuarine sand (ES). The mineralogical compositions of the four petrological end members were determined using X‐ray diffraction (XRD), quantitative XRD (QXRD), elemental analysis, and particle size distribution (PSD) measurements. Bulk samples from the four petrologic end members, after bitumen removal, were mainly composed of clay minerals (kaolinite, illite, chlorite, and mixed‐layer expandable clays) and non‐clay minerals such as quartz, carbonates, feldspars, and traces of TiO2 minerals, gypsum, and pyrite. Bulk samples of the clay end members were composed of significantly higher amounts of clay minerals and lower amounts of quartz compared with the bulk samples of the sand end members. XRD analysis of oriented preparations (air dried‐54 % RH and ethylene glycolated) of the < 0.2 μm fractions of the four end members showed that interstratified illite‐smectite of high (~30 %) and low (~10 %) expandability were observed only in clay‐rich end members, i.e. NM12‐EC and MC, respectively. Kaolinite‐smectite was only found in the < 0.2 μm fraction of the NM12‐MC with an expandability between 5 and 10 %. Interstratification of illite‐smectite was observed in the < 0.2 μm fraction of NM09‐MC and EC samples but the expandability was only 10 % for both fractions. However, kaolinite‐smectite was not found in the same fraction for NM09‐MC and EC. ES and EC had the highest and lowest bitumen contents, respectively, for the NM12, NM09, and AM10 samples.  相似文献   
982.
Thermoplastic polyurethane (TPU)/clay nanocomposite films were produced by incorporation of organo‐modified montmorillonite clay (Cloisite 30B) in TPU matrix by two different melt‐mixing routes (direct and master‐batch‐based mixing), followed by compression molding. In master‐batch mixing where the master‐batch was prepared by mixing of clay and TPU in a solvent, better dispersion of clay‐layers was observed in comparison to the nanocomposites produced by direct mixing. As a consequence, superior mechanical and gas barrier properties were obtained by master‐batch mixing route. The master‐batch processing resulted in 284 and 236% increase in tearing strength and tearing energy, respectively, with 5 wt % clay‐loading. Interestingly, in case of master‐batch mixing, the tensile strength, stiffness as well as breaking extension increased simultaneously up to 3 wt % clay‐loading. The helium gas permeability reduced by about 39 and 31% for the TPU/clay nanocomposites produced by mater‐batch and direct mixing routes, respectively, at 3 wt % loading of clay. Finally, the gas permeability results have been compared using three different gas permeability models and a good correlation was observed at lower volume fraction of clay. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46422.  相似文献   
983.
A novel poly(ethylene glycol)‐based nanocomposite hydrogels containing Fe‐octacarboxylic acid phthalocyanine (FeOCAP)/magnetic attapulgite was successfully synthesized by in situ polymerization. Fourier transform infrared spectroscopy result showed the FeOCAP/magnetic attapulgite was successfully introduced into the hydrogels matrix. Besides, the hydrogen bond interactions existed between FeOCAP/attapulgite and hydrogels, which acted as the crosslink points in the hydrogels network, and meanwhile, stabilized the nanoparticles in hydrogel without phase separation. Photocatalytic activity studies confirmed that the as‐prepared nanocomposite hydrogels had excellent photocatalytic activity for rhodamine B photodegradation, as compared to the pure hygrogels. The rhodamine B removal percentage of the hydrogels could reach nearly 100% and the kinetics of photocatalytic degradation reaction was described by the Langmuir–Hinshelwood kinetics models. The hydrogels could be reused more than five times without losing any photodegradation ability, which indicated that the hydrogels would be potentially useful in dyes wastewater treatments. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45428.  相似文献   
984.
Protein concentrates from jatropha (JPC) and soy seeds (SPC) were obtained by solubilization and acid precipitation of proteins. JPC and SPC films were prepared by the casting method, using two different montmorillonite (MMT) clay concentrations and plasticized with glycerol. Film properties were evaluated by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy, thermogravimetric analysis, tensile properties, water retention, and water vapor transmission rate (WVRT). Typical tactoid microcomposite structures were found to be heterogeneously dispersed in the films containing MMT. A small XRD peak was found in films with MMT. Slight improvements in thermal stability and tensile strength were observed in the films with MMT. Reductions in water retention and WVRT were obtained when MMT was added into the films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44459.  相似文献   
985.
The present study describes the preparation and characterization of a novel nanocomposite, based on montmorillonite clay (MMT) encapsulation in poly(ethylene glycol) (PEG) by an electrospraying process. PEG/MMT nanocomposites with MMT contents ranging from 1 to 5 wt % were successfully prepared and characterized in relation to their morphological, spectroscopic, structural, and thermal properties. Scanning electron microscopy, transmission electron microscopy, and atomic force microscopy micrographs showed that the PEG nanobeads formed spherical shapes, and with increasing amount of MMT clay, the size of the beads decreased significantly, ranging from 120 to 3.7 nm. The Fourier transform infrared spectroscopy results suggested that there was no significant chemical interaction between PEG and MMT clay. However, the d‐spacing of MMT clay in PEG/MMT increased, a clear indication of the intercalation of PEG in the interlayer spaces of MMT clay. Furthermore, the thermal stability of PEG polymer decreased upon encapsulation of MMT clay in PEG/MMT composites. Nanoindentation results showed that the hardness and Young's modulus of the PEG/MMT composites increased with 3 wt % loading of MMT. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45048.  相似文献   
986.
In this study, exfoliated montmorillonite (MMT) nanolayers were successfully encapsulated in acrylamide/acrylic acid/2‐acrylamido‐2‐methylpropanesulfonic acid (AM/AA/AMPS) terpolymer microspheres by in situ inverse suspension polymerization with the aid of the organic intercalation modification and the lateral groups of terpolymer chains. The introduction of well‐dispersed MMT nanolayers reveals a significant enhancement of the comprehensive properties of these nanocomposite microspheres, such as the viscoelasticity, thermal stability, and plugging ability. Compared with the pure terpolymer, the elastic modulus (G′) of terpolymer/2.0 wt % O‐MMT nanocomposites is 4.30 times higher and the decomposition temperature of these nanocomposites increases by 40 °C. The plugging rate reaches as high as 86.6%. Besides, surface morphology, swelling degree, and wetting behavior can be effectively tuned by varying the content of exfoliated MMT. The wetting angle increases to 82.0 ° which is suitable for modifying the formation channels. These selected nanocomposite microspheres can effectively enter and plug the high permeable microchannels. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44894.  相似文献   
987.
在曾国熙固指数曲线结度理论以及多种软土地基沉降推算方法的基础上,以某高速铁路软土试验路堤的实测沉降曲线为依据,用多种方法分别推算软土地基的最终沉降量并进行了分析比较,在不同情况下得出了适应各种情况的方法。  相似文献   
988.
张烈鑫  高隽  刘蓉 《砖瓦》2007,(10):39-42
主要研究了利用宁波建筑废弃土生产高掺量粉煤灰烧结砖和建筑废弃土的净化处理技术、物理化学和烧结性能。试验结果表明:将建筑废弃土进行净化处理后,作为高掺量粉煤灰的粘结剂是可行的;高掺量粉煤灰烧结空心砖粉煤灰最大掺量可达60%,最佳掺量为50%(重量比),这对当地新型墙体材料生产及工业废渣的综合利用将起到促进与示范作用。  相似文献   
989.
对某砖混结构住宅楼进行了基础隔震设计,采用规范规定的简化计算方法对该砖混结构的地震反应进行计算。计算结果表明:隔震结构在大震作用下基本上仍处于弹性工作状态,大大提高了地震时结构的安全性.结构由“大震不倒”提高到“大震不坏”,其抗震性能大大增加。  相似文献   
990.
高速公路通道软基低强度混凝土桩处理试验研究   总被引:8,自引:0,他引:8       下载免费PDF全文
在国内首次采用低强度混凝土桩复合地基加固高速公路通道深厚软土地基,解决通道地基处理中的二次开挖、桥头跳车等问题。介绍了在杭宁高速公路通道地基低强度混凝土桩处理中进行的桩土应力、桩土表面沉降、分层沉降、侧向变形等项目的现场测试成果,并以此对路堤荷载作用下低强度混凝土桩复合地基的性状及其处理效果进行分析。  相似文献   
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