Formation and kinetics of porous cordierite from fly ash     

Xuebin Zhang  Zuosheng Wu  Guangyao Meng  Xingqin Liu 《中国地球化学学报》2008,27(4):395-400

Porous cordierite ceramics were prepared from a mixture of coal fly ash and basic magnesium carbonate at 1100-1350℃. Porosity, flexural strength and thermal expansion coefficient of the samples sintered at 1300℃ were estimated to be 26%, 65 MPa and 4.21×10^-6/℃, respectively. The kinetics of the formation progress was investigated by stepwise isothermal dilatometry （SID） accompanied with XRD, SEM and porosity measurement. It was found that the isothermal shrinkage data from SID could be well analyzed to get kinetic parameters according to the erapirical rate equation developed by Makipirtti-Meng, dY/dt=nk（T）Y（1-Y）（Y/1-Y）^（1/n）,where Y is the fractional shrinkage during the sintering process and n is a dimensionless component. The apparent activation energy △E values for 900-1000℃ and 1050-1 150℃ were 1294 and 1778 kJ/mol, respectively.  相似文献   

安徽铜陵层控夕卡岩型铜矿床的成矿作用动力学   总被引：2，自引：0，他引：2       下载免费PDF全文

於崇文  蒋耀淞  肖正域 《地质学报》1995,69(3)

本文应用输运反应耦合过程动力学模型研究了安徽铜陵层控夕卡岩型铜矿床的成矿作用动力学机制。研究指出:(1)成矿流体的盐度梯度和流速均可促进岩浆水与地层水的混合和反应,透水层是二者发生强烈混合输运反应与成矿作用的有利场所;(2)在顺层方向上发生等温输运反应时,成矿流体与岩石接触界面处形成的移动输运反应前锋顺透水层从上游向下游缓慢推进,形成了与地层整合的层伏夕卡岩体与层状矿体;(3)在穿层方向上发生穿越等温线的梯度输运反应结果使矿物成分从镁夕卡岩向硫化物矿体发生渐变过渡。  相似文献   

东台吉乃尔湖晶间卤水综合利用途径研究   总被引：5，自引：0，他引：5  

杨建元  程温莹 《矿物岩石》1995,15(2):81-85

本文简述了东台吉乃尔湖晶间卤水蒸发试验，研究了卤水蒸发过程盐析路线及各种盐类析出规律，确定了钠、钾、硼、锂、镁、硫酸根的富集行为，提出了该晶间卤水钾、硼、锂、硫酸根综合利用工艺路线。  相似文献   

High-temperature 'clockwise'P-T paths and melting in the development of regional migmatites: an example from southern Brittany, France   总被引：1，自引：0，他引：1  

K. A. JONES  MICHAEL BROWN 《Journal of Metamorphic Geology》1990,8(5):551-578

The Southern Brittany Migmatite Belt (SBMB), which evolved through the metamorphic peak between c. 400 Ma and c. . 370 Ma ago, consists of a heterogeneous suite of high-grade gneisses and anatectic migmatites, both metatexites and diatexites. Rare garnet-cordierite gneiss layers record evidence of an early prograde P-T path. In these rocks, growth-zoned garnet cores and a sequence of included mineral assemblages in garnet, from core to rim, of Qtz + Ilm + Ky, Pl + Ky + St + Rt + Bt and Pl + Sil + St + Rt + Bt constrain a prograde evolution during which the reactions Ilm + Ky + Qtz→ Aim + Rt, Ms + Chl→ St + Bt + Qtz + V and St + Qtz→ Grt + Sil + V were crossed. Parts of this prograde evolution are preserved as inclusion assemblages in garnet in all other rock types. In all rock types, garnet has reverse zoned rims, and garnet replacement by cordierite and/or biotite and plagioclase suggests the following reactions have occurred: Grt + Sil + Qtz→ Crd → Hc ± Ilm, Bt + Sil + Qtz → Crd ± Hc → Ilm → Kfs + V and (Na + Ca + K + Ti) + Grt → Bt + Pl + Qtz. Microstructural analysis of reaction textures in conjunction with a petrogenetic grid has enabled the construction of a tightly constrained 'clockwise' P–T path for the SBMB. The high-temperature part of the path has a steep dT/dP slope characteristic of near isothermal decompression. It is proposed that the P-T path followed by the SBMB is the result of the inversion, by overthrusting, of a back-arc basin and that such a tectonic setting may be applicable to other high-temperature migmatite terranes. The near isothermal decompression is at least partly driven by the upward (diapiric) movement of the diatexite/anatectic granite core of the SBMB.  相似文献   

基于DEM的秦岭山地1月气温及0℃等温线变化   总被引：9，自引：5，他引：4  

白红英  马新萍  高翔  侯钦磊 《地理学报》2012,67(11):1443-1450

以秦岭南北39 个气象站点1959-2009 年1 月平均气温为基础, 考虑地形因素对温度场的影响, 采取基于DEM的空间插值方法, 获取秦岭山地复杂地形下的1 月气温空间插值数据集, 并在此基础上提取1 月0℃等温线, 研究了50 年来秦岭山地1 月平均气温和1 月0℃等温线的变化情况。结果表明:秦岭南北1 月月均气温均表现为上升趋势, 温度变化倾向率约为0.2℃/10a;50 年来秦岭1 月0℃等温线发生了明显上升, 平均上升高度为143.7 m。从经度上看, 107°E~109°E 范围内1 月0℃等温线所处海拔高度的变化最为强烈, 50 年来上升高度达166.2 m, 明显高于东西两段;1993 年是秦岭地区气温明显上升的突变点, 气温突变后1 月0℃等温线比突变前平均上升了113.82 m。  相似文献   

四川盆地早白垩世红层磁倾角偏低研究          下载免费PDF全文

赵千  王彬  张浩东  王志瑶 《地球物理学报》2017,60(5):1825-1837

对四川盆地东北部巴中地区和西部雅安地区早白垩世红层分别采集9块手标本,进行了详细的古地磁学研究.系统退磁获得两地的特征剩磁,其中巴中地区平均方向为,倾斜校正之前:D_g/I_g=25.3°/19.0°,k=18.6,α_(95)=8.8°;倾斜校正之后:D_s/I_s=25.8°/18.9°,k=24.3,α_(95)=7.6°.雅安地区平均方向为,倾斜校正之前:D_g/I_g=24.5°/45.0°,k=15.7,α_(95)=9.0°;倾斜校正之后:D_s/I_s=356.7°/35.6°,k=28.5,α_(95)=6.6°.磁化率各向异性实验结果显示两地均未受到显著的构造应力影响.等温剩磁各向异性(AIR)实验结果,巴中地区IRMz/IRMLx平均值为0.8194,表明18%的压实率;雅安地区IRMz/IRMx平均值为0.8909,表明11%的压实率,计算得到巴中和雅安地区校正后的磁倾角分别为22.7°和38.8°.根据等温剩磁各向异性(AIR)实验和Tauxe and Kent(2004)提出的EI校正法得到的结果表明,四川盆地早白垩世陆相碎屑岩层中存在沉积压实作用造成的磁倾角偏低现象,而且川东北巴中地区的偏低程度强于川西雅安地区.  相似文献   

Theoretical analyses of chemical dissolution‐front instability in fluid‐saturated porous media under non‐isothermal conditions          下载免费PDF全文

Chongbin Zhao  B. E. Hobbs  A. Ord 《国际地质力学数值与分析法杂志》2015,39(8):799-820

This paper mainly deals with the theoretical aspects of chemical dissolution‐front instability problems in two‐dimensional fluid‐saturated porous media under non‐isothermal conditions. In the case of the mineral dissolution ratio (that is defined as the ratio of the dissolved‐mineral equilibrium concentration in the pore fluid to the molar concentration of the dissolvable mineral in the solid matrix of the fluid‐saturated porous medium) approaching zero, the corresponding critical condition has been mathematically derived when temperature variation effects are considered. As a complementary tool, the computational simulation method is used to simulate the morphological evolution of chemical dissolution fronts in two‐dimensional fluid‐saturated porous media under non‐isothermal conditions. The related theoretical and numerical results have demonstrated that: (i) a temperature increase in a non‐isothermal chemical dissolution system can have some influence on the propagation speed of the planar chemical dissolution front in the system. Generally, the chemical dissolution front in the non‐isothermal chemical dissolution system propagates slower than that in the counterpart isothermal chemical dissolution system when the temperature of the non‐isothermal chemical dissolution system is higher than that of the counterpart isothermal chemical dissolution system; (ii) a temperature increase in the non‐isothermal chemical dissolution system can stabilize the chemical dissolution front propagating in the system, because it can cause a decrease in the Zhao number of the system but does not affect the critical Zhao number of the system; and (iii) the temperature gradient in the upstream direction of a chemical dissolution front is smaller than that in the downstream direction of the chemical dissolution front when the non‐isothermal chemical dissolution system is supercritical. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

等温大气压高方程在气压剖面高度计算中的应用   总被引：2，自引：0，他引：2  

董涛  李永军 《海洋技术学报》2011,30(1):88-90,94

气象探测仪器获取空中气象数据时,需要确定气象数据对应的气压高度,以形成剖面测量数据.将等温大气压高方程应用于实际的气压剖面高度计算中,确定计算的边界条件并进行误差估算,并通过实际算例,验证了理论计算的有效性.  相似文献   

沁水盆地寿阳区块煤层气井网优化及采收率预测     

王振云  唐书恒  孙鹏杰  张松航  朱卫平 《中国煤炭地质》2013,(10)

煤层气采收率的确定对于产业的发展具有较大指导意义。通过对类比法、解吸法、等温吸附曲线法及储层数值模拟法适用性分析,并结合沁水盆地寿阳区块煤储层特征,应用COMET3数值模拟软件,对15号煤储层生产数据进行历史拟合,校正了基础参数,基于不同井距设计了6种不同的井网方案,对各种方案进行了产能数值模拟及采收率预测。根据预测结果总结出寿阳区块采收率与钻井数关系变化规律,指出最优井间距为288m×216m,对应的采收率为50.4%。  相似文献   

孔石莼(Ulva pertusa)LAMP-LFD快速检测方法的建立     

周前进  陈先锋  蔡怡  段丽君  段维军  苗亮  陈炯 《海洋与湖沼》2016,47(2):380-389

采用环介导等温扩增技术(loop-mediated isothermal amplification,LAMP)进行核酸扩增,凭借横向流动试纸条(lateral flow dipstick,LFD)完成扩增产物检测,建立了可快速检测孔石莼(Ulva pertusa)的LAMP-LFD方法。该方法首先在孔石莼的内转录间隔区序列(internal transcribed spacer,ITS)的8个种内保守区域设计6条特异性引物(上游内引物由生物素标记),进行由生物素标记的LAMP反应;同时,在两条外引物的有效扩增区段内设计1条异硫氰酸荧光素(fluorescein isothiocyanate,FITC)标记的探针,生物素标记的LAMP产物与FITC标记的探针特异性杂交后,在LFD上完成结果显示。优化后LAMP的反应条件为63°C反应50min,加上探针杂交与LFD检测共需60min。结果表明,利用该LAMP-LFD方法可特异性地检出孔石莼,对浒苔(Ulva prolifera)等9种常见藻类的检测均呈阴性。利用该方法最低可检测到3.04×10~(–2) pg/μL的孔石莼基因组DNA,是以LAMP外引物进行的常规PCR方法的1000倍。针对一定数量的实际样本的检测结果表明,LAMP-LFD方法与传统的形态学观察的结果一致。因此,本研究建立的孔石莼LAMP-LFD快速检测方法,具有特异性强、灵敏度高、操作简便等优点,有望成为我国东部沿海孔石莼快速检测和定期监测的有效技术手段。  相似文献