scholarly journals Hydrothermal alteration of sediments in the high-temperature reaction zone at Central Hill of Escanaba Trough, Gorda Ridge

2019 ◽  
Vol 98 ◽  
pp. 08003
Author(s):  
Konstantin Galin ◽  
Alexandra Khakhina ◽  
Victor Kurnosov ◽  
Yurii Konovalov

In sediments from Holes ODP 1038A and 1038H, drilled near the hot springs at Central Hill, Escanaba Trough (Gorda Ridge), redistribution of major elements occurs during the water-rock interaction. Contents of Si, Fe, Mg, Ca, Na and K have changed in altered sediments. In this process, an increase/decrease in contents of major elements in altered sediments shows a decrease/increase in their contents in fluids. The irregular distribution of major elements in altered sediments resembles a layer pie, which reflects the existence of lateral flows of hydrothermal fluids.

2020 ◽  
pp. 146808742096933
Author(s):  
Xiangyu Meng ◽  
Sicheng Liu ◽  
Jingchen Cui ◽  
Jiangping Tian ◽  
Wuqiang Long ◽  
...  

A novel method called high-pressure air (HPA) jet controlled compression ignition (JCCI) based on the compound thermodynamic cycle was investigated in this work. The combustion process of premixed mixture can be controlled flexibly by the high-pressure air jet compression, and it characterizes the intensified low-temperature reaction and two-stage high-temperature reaction. The three-dimensional (3D) computational fluid dynamics (CFD) numerical simulation was employed to study the emission formation process and mechanism, and the effects of high-pressure air jet temperature and duration on emissions were also investigated. The simulation results showed that the NOx formation is mainly affected by the first-stage high-temperature reaction due to the higher reaction temperature. Overall, this combustion mode can obtain ultra-low NOx emission. The second-stage high-temperature reaction plays an important role in the CO and THC formation caused by the mixing effect of the high-pressure air and original in-cylinder mixture. The increasing air jet temperature leads to a larger high-temperature in-cylinder region and more fuel in the first-stage reaction, and therefore resulting in higher NOx emission. However, the increasing air jet temperature can significantly reduce the CO and THC emissions. For the air jet duration comparisons, both too short and too long air jet durations could induce higher NOx emission. A higher air jet duration would result in higher CO emission due to the more high-pressure air jet with relatively low temperature.


2014 ◽  
Vol 633 ◽  
pp. 61-64
Author(s):  
Lei Li ◽  
Rui Long Wen ◽  
Xiao Guang Zhang ◽  
Cheng Biao Wang ◽  
Ming Hao Fang ◽  
...  

Cordierite samples were prepared using quartz sand tailings, industrial alumina and magnesite tailings as raw materials by high-temperature reaction. The influence of mineral composition and sintering temperature on the final phase composition and physical properties of cordierite were studied. The results shown that a large number of cordierite generated at 1300 °C. When the ratio of Al2O3/SiO2 equals to 1.08, the flexural strength of samples increased to 27.66 MPa.


1995 ◽  
pp. 71-76
Author(s):  
Kentaro Tsuchiya ◽  
Hiroyuki Matsui ◽  
Masaaki Oya ◽  
Gabrielle Dupré

Sign in / Sign up

Export Citation Format

Share Document