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981.
蒙皂石粘土矿物不正常转化的研究——以准噶尔盆地为例   总被引:2,自引:2,他引:0  
利用岩石薄片和X射线衍射资料,分析了准噶尔盆地腹部地区蒙皂石粘土矿物的不正常转化。该区庄1井、成1井和董1井在超压段内粘土矿物转化出现异常现象,蒙皂石以及伊/蒙混层的相对含量随深度增加有所增加,而伊利石的相对含量随深度增加有所减少。结合前人的研究资料,讨论了超压对粘土矿物转化的影响。超压能增加蒙皂石层间水的稳定性,阻碍超压仓与外界流体和离子的交换,使伊利石含量有所减少。同时,火山岩屑物质的大量存在可能导致在晚成岩阶段伊/蒙混层含量较高,蒙皂石的含量也有所增加。  相似文献   
982.
Magnesium silicate hydrate gels (M-S-H) have been prepared by precipitation. The range of gel compositions lie between Mg/Si molar ratios 0.67-1.0. The gels were subject to short cure, approximately 24 h at approximately 22 °C and longer cure, 180 days at 85 °C, following which they were characterised by XRD, FT-IR and solid-state 29Si NMR. Ageing at longer times and higher temperatures somewhat improves the local ordering. The nature of the partially ordered structures is related to those of M-S-H mineral phases. The structures and compositions of M-S-H gels differ from those of C-S-H gels and partly on that account, C-S-H gels contain little magnesium while M-S-H gels in blended cements coexist with C-S-H but contain little calcium.  相似文献   
983.
The combination of high-resolution chemically sensitive soft X-ray microscopy with stereo imaging and processing techniques presented here forms a novel tool for the investigation of aqueous colloidal systems. Information about the spatial distribution within the sample is provided with small calculation effort processing just a pair of stereo micrographs. Thus, the extension towards investigation of dynamical behaviour is possible on the part of the experiment as well as of the processing.
The potential of this technique is demonstrated with applications in aqueous soil and clay samples. Within these samples, haematite particles are identified taking advantage of the elemental contrast at the Fe-L edge around E = 707 eV. In combination with stereo microscopy, information about spatial arrangements are revealed and correlated to electrostatic interactions of the different mixtures, addressing to an actual question of soil scientists. The technique allows in-situ sample manipulation, which is demonstrated by a test specimen where particles were added during imaging.  相似文献   
984.
Historically, phlogopite and olivine have been mined in the Silver City Dome District in Kansas, USA, from lamproite ultra-potassic igneous rock for use as a supplement in cattle feed. Micro-Lite LLC is now evaluating processing techniques for recovery of phlogopite to be used for reinforcement in plastics, high temperature applications, and electrical insulators, which requires a higher grade phlogopite product. To determine the purity of the processed ore, QEMSCAN® was utilised to identify and quantify phlogopite and impurities, including olivine, pyroxenes, feldspars, titanium phases (mainly titanite and perovskite), apatite, magnetite, chromite, and other phases. Samples were prepared and analysed in a manner to decrease or eliminate preferred orientation of phlogopite to provide accurate quantitative results. The results show that the flotation product has a higher concentration of phlogopite at 87% (by mass), compared to 78% in the hydrosizer product. The main impurity phase in both products is olivine (10% in the flotation product and 18% in the hydrosizer product). In the hydrosizer product, 15% of the sample consists of liberated phlogopite particles, while in the flotation product 58% of the sample occurs as pure, liberated phlogopite particles.  相似文献   
985.
ABSTRACT The ability of phytases from fresh fruits and vegetables to degrade phytate in foods was determined in vitro. In contrast to the more consistent presence of phytase in vegetables, only a few fruits contained detectable phytase activity. The highest phytase activities were 121 and 97 nmol min‐1 g‐1 in scallion leaves and avocado fruit, respectively. Avocado fruit also contained 0.14% phytate on a wet‐weight basis. Crude phytase extracts were incubated with ground corn tortillas or refried beans at 37 °C. Most of the phytate was degraded within 30 min by a 4‐fold excess by dry weight of scallion leaves. Avocado extracts incubated alone metabolized most of their endogenous phytate within 2 h.  相似文献   
986.
本文分析了国内非金属矿干燥设备的现状与发展趋势,针对目前设备存在的问题提出了新型专用干燥设备的性能要求,并对市场上可能出现的新型干燥设备的机型做了预测。  相似文献   
987.
The electrokinetic features and interfacial water structure, as revealed from molecular dynamics simulations (MDS) are considered with respect to the anisotropic features of selected two layer silicate minerals. Planar structures of kaolinite and antigorite are compared to the, compositionally equivalent, tubular structures of halloysite and chrysotile with respect to the pH dependency of zeta potential as determined from the electrophoretic mobility measurements. The importance of the atomic mismatch between the tetrahedral and octahedral sheets in a particular bilayer is discussed in order to explain the electrokinetic behaviour of these two layer silicate minerals. Interfacial water structure from MDS suggests that the silica tetrahedral surface is not wetted by water. In the case of planar silicates structural imperfections are considered to explain wetting characteristics. The possibility of polarity reversal (domain inversion) within a tetrahedral/octahedral layer and an out‐of‐order layer (inserted layer) within the tetrahedral/octahedral stack are considered in order to explain electrokinetic behaviour and wetting characteristics.  相似文献   
988.
电子探针分析表明,翘皮缺陷内部存在聚集的大型夹杂物,翘皮缺陷的形成,是在穿管深加工过程中,管壁不断减薄,夹杂物逐渐外露,表皮外翻所致。翘皮处的夹杂物矿相是以铝酸钙和黄长石为主,还存在少量锆刚玉变质体以及镁铝尖晶石,跟下水口侵蚀反应产物相吻合;聚集的大型夹杂物与下水口侵蚀后的脱落物有关。  相似文献   
989.
990.
Surface modification of wollastonite particles using titanate as a modification agent incorporated by simultaneous wet ultra-fine grinding in a laboratory stirred mill was investigated.The physical,physic-chemical and application properties of the modified wollastonite were measured and evaluated.The results showed that grinding intensity markedly influences the modification effect because of the mechano chemical effect.The hydrophilic surface of wollastonite was turned into a hydrophobic one after modifica...  相似文献   
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