Article
Multidisciplinary Sciences
Tobias Burger, Bosun Roy-Layinde, Rebecca Lentz, Zachary J. Berquist, Stephen R. Forrest, Andrej Lenert
Summary: Recent advances in thermophotovoltaic power generation have improved efficiency at high temperatures, but there is still room for improvement in converting lower temperature waste, solar, and nuclear heat streams. The concept of transmissive spectral control enables efficient recuperation by allowing below-bandgap photons to be absorbed by a secondary emitter. This study presents a semitransparent TPV cell that achieves high efficiency by absorbing less than 1% of below-bandgap radiation.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Metallurgy & Metallurgical Engineering
Xiao-yan Zhang, Min Zhao, Lang Liu, Chao Huan, Ki-il Song, Mu-yan Xu, De Wen
Summary: The study investigates the thermal accumulation process of cemented tailings backfill (CTB) through numerical simulation, focusing on the effects of thermal accumulation time, slurry proportions, and temperature conditions. Results show that the total thermal accumulation capacity of CTB can increase by approximately 85% within 10-90 days. Surrounding rock temperature and initial temperature have a more significant impact on thermal accumulation capacity compared to slurry proportions, with surrounding rock temperature and initial temperature changes improving the capacity more effectively. Additionally, heat conduction plays a major role in the thermal accumulation process, with the average heat conduction capacity being approximately 25 times that of heat convection capacity.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2021)
Article
Green & Sustainable Science & Technology
Mei Wang, Peng Liu, Lang Liu, Mingli Geng, Yu Wang, Zhefeng Zhang
Summary: The deep mine radiation cooling system using cold load and storage functional cemented paste backfill has proven to be more effective than conventional cooling methods. Different backfill methods result in different cooling performances due to their positional relationships. The downwards backfill method accelerates heat transfer and meets the temperature requirements of deep mine mining. The research provides a reference for improving the cooling effect of functional cemented paste backfill and mine cooling system design using this method.
Article
Construction & Building Technology
Zepeng Yan, Shenghua Yin, Xun Chen, Leiming Wang
Summary: Cemented tailing-waste rock backfill (CTWB) plays an important role in improving the ecological environment of the mine. The rheological and wall-slip characteristics of CTWB paste were analyzed and a numerical model was established to simulate the flow process. The results showed that CTWB is a yield-plastic fluid with shear-thickening phenomenon at certain solids content. Increasing the coarse aggregate content improved the fluidity of the paste. The slip behavior of the CTWB paste was significantly affected by the tailing-waste rock ratio, inlet velocity, and solid content.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Shenghua Yin, Zepeng Yan, Xun Chen, Rongfu Yan, Dapeng Chen, Junwei Chen
Summary: Cemented tailings and waste-rock backfill (CTWB) was studied using a combination of laboratory testing and deep learning. A long short-term memory (LSTM) network prediction model based on genetic algorithm (GA) optimization was developed to predict the unconfined compressive strength (UCS). The GA-LSTM model showed good prediction effect with an R2 of 0.9956 in the training set and 0.9763 in the test set. Deep learning models exhibited higher accuracy than machine learning models.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Nan Yao, Yiding Liu, Qihu Wang, Felix Oppong, Tianyu Huang, Zhijin Zhou, Ping Du
Summary: The relation between segregation and strength of cemented waste rock backfill (CWRB) was analyzed by examining the aggregate distribution, uniaxial compressive strength (UCS), and failure law of the CWRB with different mass concentrations and accelerator contents. The test results showed that higher mass concentration and accelerator content led to more uniform aggregate distribution, improved skeleton structure, increased UCS, and changed material properties from plastic to elastic. The strength of the CWRB increased exponentially with the increase of the aggregate uniformity coefficient.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Mechanics
Guangzhi Li, Xinshuai Shi, Jianguo Ning, Weiqiang Chen, Zhaohui Zhang, Jun Wang, Shang Yang, Yuan Gao
Summary: This study investigates the dynamic behavior of Cement Waste Rock Backfill (CWRB) under impact loading. The results show that the response of CWRB with different particle size distributions to impact strain rate is inconsistent. Higher strain rates further deteriorate the dynamic compressive behavior of CWRB due to pore structure effect. This research enhances our understanding of CWRB behavior under dynamic loading and contributes to the safety and efficiency of mining operations.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Environmental Sciences
G. Montavon, S. Ribet, Y. Hassan Loni, F. Maia, C. Bailly, K. David, C. Lerouge, B. Made, J. C. Robinet, B. Grambow
Summary: This study investigates the mobility of uranium in the Callovo-Oxfordian clay formation. Results show that the clay phase has strong adsorption for U(IV) but weak adsorption for U(VI). The clay phase is considered the largest reservoir of naturally-occurring U, but only a small fraction is adsorbed.
Review
Environmental Sciences
Guan Chen, Yicheng Ye, Nan Yao, Fanghui Fu, Nanyan Hu, Zhen Zhang
Summary: Uniaxial compression tests were conducted on cemented backfill with different particle size gradations to study the effect of backfill aggregate particle size on compressive strength and failure mode. The damage evolution mechanism of cemented backfill with different particle size gradations was discussed by analyzing the characteristics of acoustic emission during the failure process.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Energy & Fuels
Chao Huan, Sha Zhang, Xiaoxuan Zhao, Shengteng Li, Bo Zhang, Yujiao Zhao, Pengfei Tao
Summary: The increase in porosity has a negative effect on the heat exchange performance of CPB, but in conditions with seepage flow, the heat transfer capacity of CPB could be effectively improved. A higher hydraulic conductivity corresponds to a higher heat transfer performance of CPB.
Article
Environmental Sciences
Wei Liu, Shufei Liang, Qingwei Huang, Yueping Qin
Summary: This research establishes a transient heat transfer model to estimate the temperature rise and heat transfer of the surrounding rock of subway tunnels. The results show that the temperature of the surrounding rock fluctuates following the periodic temperature fluctuation of the ground atmosphere and the periodic temperature variation of the tunnel wind. The overlying strata of the tunnel are heavily affected by this phenomenon. Moreover, the shallower the tunnel is buried, the greater the influence and the higher the temperature rise in the surrounding rock.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Huafu Qiu, Fushun Zhang, Weibo Sun, Lang Liu, Yujiao Zhao, Chao Huan
Summary: This study investigated the effects of cement-sand ratio and waste rock content on the strength and permeability of cemented tailings backfill. The results showed that increasing waste rock content initially increased the compressive strength and permeability of the backfill, but then decreased it. Decreasing the cement-sand ratio resulted in lower compressive strength and higher permeability due to the production of more micro-cracks in the curing process.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Energy & Fuels
Rong Wan, Lu Shen, Hengjun Liu, Songfeng Ma, Shangwen Duan, Dequan Kong, Ting Wang, Chen Zheng
Summary: This study prepared a stable shape-stable phase change material (SSPCM) for ground source heat pump (GSHP) backfilling. After 25 high and low temperature cycles, the mass loss rate of SSPCM was less than 5%. The study also found that the thermal conductivity of the SSPCM increased with the decrease of the mixing ratio of SSPCM and the increase of water content. Therefore, adding SSPCM to the backfill material is beneficial to the long-term intermittent operation of GSHPs.
Article
Energy & Fuels
Andreia Santos, Fernando Almeida, Fernando Neto
Summary: The study focused on the characterization of the thermal and physical properties of a Thermal Energy Storage (TES) reservoir filled with crushed hematite ore, aiming to store energy as sensible heat and proposed a numerical model to simulate temperature variations. Results suggest that hematite is a suitable heat storage material with high specific heat and low thermal conductivity, leading to minimal heat loss, and efficiency calculations for a large-scale energy storage system were conducted using the model.
JOURNAL OF ENERGY STORAGE
(2021)
Article
Energy & Fuels
Pai Ning, Feng Ju, Meng Xiao, ZeQuan He, Dong Wang
Summary: Heat storage functional backfill is important for realizing the synergistic mining of geothermal and coal resources. This study investigated the thermal-mechanical properties and heat transfer characteristics of heat storage functional backfill body (HSFBB). A composite phase change material (CPCM) was prepared using paraffin and expanded graphite, and its optimal ratio was determined. The HSFBB was then prepared using coal gangue, tailings, CPCM, and cement, and the influence of CPCM content on the thermal and mechanical properties of HSFBB was determined. Numerical simulation was used to analyze the influence of CPCM on the heat transfer characteristics of HSFBB. The results showed that CPCM content had a significant influence on the properties and behavior of HSFBB.