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1.
Xiao-qing Niu Ji-chun Chen 《北京科技大学学报(英文版)》2014,(10):1028-1032
The effects of calcination and modification on the morphology (shapes and textures) and crystal structure of anhydrite powders were studied. The results show that, calcination at 100℃ causes anhydrite to disintegrate into smaller crystals, accompanied by a slight in- crease in d-spacing. Without calcination and modification, the solidification time and curing time of anhydrite are 15 and 77 h, respectively. After the treatment, however, the solidification time and curing time are shortened significantly to 9.5 and 14 rain, respectively. The com- pressive and flexural strengths of hydration products made from the treated anhydrite reach 10.2 and 2.0 MPa, respectively. The much shorter solidification and curing time make it possible to use anhydrite as a building and construction material. 相似文献
2.
采用DSC研究了聚丙烯(PP)及聚丙烯/硬石膏复合材料的非等温结晶动力学,对所得数据用修正Avrami方程的Jeziorny法和Mo法进行处理。结果表明:硬石膏的加入提高了PP的结晶温度Tp和结晶速率,降低了结晶活化能ΔE,使实际降温速率下PP更易结晶。同样的含量下,经铝酸酯偶联剂改性硬石膏使PP结晶速率加快,但ΔE有小幅上升。研究表明,硬石膏有异相成核作用,填加20%时异相成核多于填加10%时,铝酸酯偶联剂的改性对该作用无明显影响。 相似文献
3.
通过烃源条件、储盖组合、圈闭类型、天然气运聚特征和保存条件等方面的深入分析,发现川中-川南过渡带嘉二段气藏成藏条件优越,其中天然气的近源垂向运聚和理想的保存条件是嘉二段成藏的重要保障。同时,认识到有利的沉积相、建设性成岩作用、背斜构造、烃源断层和硬石膏岩层是该区嘉二段气藏成藏的主要控制因素,其综合作用使得该气藏成藏规律复杂。在此基础上,对研究区嘉二段气藏的有利成藏区块进行评价,认为该区嘉二段气藏的勘探开发潜力很大。 相似文献
4.
5.
天然硬石膏的活性激发及改性 总被引:2,自引:0,他引:2
选取硫酸钾作为激发剂对天然硬石膏进行活性激发,并分别掺入硅酸盐水泥与半水石膏进行改性。研究了这些组分对天然硬石膏力学性能及耐水性能的影响规律,实验结果表明,硫酸钾对强度提高显著,硅酸盐水泥对强度与软化系数均有很大的改善作用,而半水石膏对强度与软化系数也有一定程度的影响。 相似文献
6.
基于目前水泥胶凝材料价格大幅上调导致膏体充填成本高昂的实际境况,为降低充填成本,以工业废弃氟石膏为主要研究对象进行相关研究。利用氟石膏代替水泥,结合废石、粉煤灰、生石灰等掺加料,并辅以一定量的添加剂,开展氟石膏基新型膏体充填材料配比试验研究。通过坍落度、扩展度等试验确定材料的最优配比,并对膏体进行单、三轴及SEM试验,分析其宏微观结构。研究结果表明:质量浓度增大0min至120min,坍落度、扩展度损失率随之增大,泌水率却逐渐减小;最优配比所制成氟石膏基膏体的单轴压缩应力—应变曲线属于弹塑性曲线,最高可达6~7MPa;单轴与三轴压缩试验后,膏体表面未出现大的破裂面,且随围压的增加,应力—应变曲线不再出现峰值应力;所制充填材料的水化物主要包括钙矾石(AFt)、水化硅酸钙凝胶(C-S-H凝胶)和二水硫酸钙(CaSO4?2H2O)。氟石膏基新型膏体充填材料的配制具有深远的影响,为实现高效安全、绿色可持续的矿山开采提供了保障。 相似文献
7.
The hydration performances of slag cement mixed by limestone and anhydritehave been studied. The phase compositions andmicrostructures of the hydrates were determinedand analysed by XRD and SEM. It is discoveredthat when slag cement is mixed with limestoneand anhydrite. the hydrations of the clinker andslag are speeded. The amount of ettringite andhydrate calcium silicate are increased and the me-chanical strength of slag cement are enchanced. 相似文献
8.
针对如何保证室内粉刷石膏的施工质量进行了探讨,分别从原料、基层处理、操作工艺、成品保护四方面进行了介绍,以指导实践,保证室内粉刷石膏施工符合要求,为后续装修提供保障。 相似文献
9.
DOLOMITIZATION AND ANHYDRITE PRECIPITATION IN PERMO-TRIASSIC CARBONATES AT THE SOUTH PARS GASFIELD, OFFSHORE IRAN: CONTROLS ON RESERVOIR QUALITY 总被引:2,自引:0,他引:2
Dolomitization and related anhydrite cementation can complicate the characterization of carbonate reservoirs. Both processes have affected the Permo-Triassic Upper Dalan – Kangan carbonates, the main reservoir at the South Pars gasfield, offshore Iran. The carbonates were deposited in a shallow-marine ramp or epeiric platform and, according to previous studies, underwent intense near-surface diagenesis and minor burial modification. Detailed petrographical and geochemical analyses indicate that dolomitization and anhydrite precipitation can be explained in terms of the sabkha/seepage-reflux models. The early dolomites then re-equilibrated or re-crystallized in a shallow burial setting. Evaluation of poroperm values in different reservoir intervals indicates that replacive dolomitization in the absence of anhydrite precipitation or with only patchy anhydrite has enhanced the reservoir quality. Where anhydrite cement is pervasive and has plugged the rock fabric, poroperm values are significantly decreased. As emphasized in previous studies and confirmed here, dolomitization and anhydrite cementation, together with original facies type, are the major factors controlling reservoir quality in the Dalan – Kangan carbonates at South Pars. When associated with minor anhydrite cementation, replacive dolomitization has enhanced reservoir quality by increasing permeability. However, porosity in fabric-retentive dolomite was apparently inherited from the precursor rock and therefore reflects the original depositional environment. Low-temperature dolomitization is commonly fabric-selective and partially fabric-retentive. Whole rock stable isotope thermometry indicates that fabric-destructive dolomites in the reservoir rocks formed at temperatures above 22°C, whereas fabric-retentive dolomites and associated anhydrites formed in surface and near-surface conditions. Fabric-destructive dolomite or dolomite neomorphism post-date fabric-retentive dolomite and continued to form in deep burial conditions (∼1400m). These observations may explain why fabric-retentive dolomite and anhydrite fabrics are traversed by stylolites. 相似文献
10.
煅烧硬石膏激发粉煤灰活性的研究 总被引:5,自引:1,他引:4
对高温煅烧硬石膏的分解温度与分解率,分解产物的活性与对粉煤灰的激发效应进行了试验研究,提出了初期和后期两期激发机理。 相似文献