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1.
Sheng Hua Tan Shi Wei Wong Du Jia Chin Min Lee Lee Ying Hui Ong Siaw Yah Chong Azman Kassim 《Environmental Earth Sciences》2018,77(16):589
Rainfall-induced landslide is a common geohazard in tropical and humid regions. Capillary barrier system (CBS) is a popular and widely studied mitigating measure for rainfall-induced landslides. However, several previous studies have shown that the performance of the conventional CBS under intense rainfalls has not been particularly convincing. This paper aims to explore the feasibility and effectiveness of a newly proposed system, known as “biomediated capillary barrier system” (B-CBS) in minimizing water infiltration into soil. A one-dimensional soil column was used to investigate the infiltration characteristics of the proposed system. The results showed that the B-CBS of biomediated residual soil overlying original residual soil (Test IV) could effectively control the infiltration into soil by taking advantage of the less-permeable biomediated soil cover. The B-CBS of biomediated residual soil overlying gravelly sand (Test V) and the three-layered B-CBS of fine sand overlying gravelly sand and biomediated residual soil (Test VI) showed the best performance in terms of minimizing the water infiltration. A suction of about 5 kPa still remained in the soil column after 60 min of infiltration from the ponded water on the soil surface. 相似文献
2.
D. T. Tan S. K. Chin P. E. Poh Y. H. Lee 《International Journal of Environmental Science and Technology》2018,15(6):1211-1222
The generation of huge amount of liquid waste known as palm oil mill effluent is a major problem in oil palm industry. Meanwhile, anaerobic biodegradation of such organic effluent at thermophilic condition is a promising treatment technology due to its high efficiency. However, storage and transportation of thermophilic mixed culture sludge are challenging due to constant biogas generation and heating requirement. Hence, drying of thermophilic sludge was conducted to obtain dormant thermophiles and thus enables easier handling. In this study, thermophilic sludge was dried using heat pump at 22 and 32 °C as well as hot air oven at 40, 50, 60, and 70 °C. Subsequently, quality of dried sludge was examined based on most probable number enumeration, chemical oxygen demand, and methane yield. Average drying rate was found to increase from 3.21 to 17.84 g H2O/m2 min as drying temperatures increases while average moisture diffusivity values ranges from 5.07 × 10?9 to 4.34 × 10?8 m2/s. Oven drying of thermophilic mixed culture resulted in highest chemical oxygen demand removal and lowest log reduction of anaerobes at 53.41% and 2.16, respectively, while heat pump drying resulted in the highest methane yield and lowest log reduction of methanogens at 53.4 ml CH4/g COD and 2.09, respectively. To conclude, heat pump at 22 °C was most suitable drying technique for thermophilic mixed culture as the original methane-producing capability was largely retained after drying, at a slightly lower yet still comparable chemical oxygen demand removal when palm oil mill effluent was treated with the rehydrated culture. 相似文献
3.
中国地质学会2020年度“十大地质科技进展” 总被引:1,自引:0,他引:1
大庆油田等:松辽盆地北部古龙页岩油勘探取得重大发现大庆油田在松辽盆地北部古龙凹陷青一段地层的纯页岩内实现水平井产量重大战略突破,试油获高产工业油气流,定产试采表现出稳定的高产能力,平面上15口直井试油证实古龙页岩油平面分布范围广,规模立体含油,轻质油带具有较好的产油能力,轻质油带页岩油气资源量达到几十亿吨。通过岩心精细描述及实验分析化验数据,建立了以古沉积环境控制原始优质烃源岩发育、适中的热演化程度控制油气富集。 相似文献
4.
<正>由《中国学术期刊(光盘版)》电子杂志社有限公司、中国科学文献计量评价研究中心和清华大学图书馆出版的《中国学术期刊影响因子年报(自然科学与工程技术)(2022年版)》(简称《年报》)已发布。根据《年报》的统计结果,在105种地质类期刊中,《地球学报》2022年影响力指数为377.707,排名第21,复合影响因子是2.578,分区为Q1(表1)。《年报》采用的统计分析方法体现了如下8个特点: 相似文献
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