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Preparation and Performance of Ternary Early Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 130-140页

作者： LIU Jian CHEN Meiting JI Xiaoli XU Chao WANG Chunmei department of Safety Science and engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Efficient mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China department of Chemical engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao Wu Xingying Lan Yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt department of Chemistry Xi'an Jiaotong-Liverpool University department of Mechanical and Mechatronics engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： Condensation reactions

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid Ahmed Tadjer Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical engineering department Mohamed Boudiaf University of M’silaM’sila28000Algeria department of Civil and Environmental engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Simulation and optimization approach for uncertainty-based short-term planning in open pit mines

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International Journal of mining Science and Technology 2018年第2期28卷 153-166页

作者： Shiv Prakash Upadhyay Hooman Askari-Nasab department of Civil and Environment engineering School of Mining and Petroleum Engineering University of Alberta

Accuracy in predictions leads to better planning with a minimum of opportunity lost. In open pit mining,the complexity of operations, coupled with a highly uncertain and dynamic production environment,limit the accuracy of predictions and force a reactive planning approach to mitigate deviations from original plans. A simulation optimization framework/tool is presented in this paper to account for uncertainties in mining operations for robust short-term production planning and proactive decision making. This framework/tool uses a discrete event simulation model of mine operations, which interacts with a goalprogramming based mine operational optimization tool to develop an uncertainty based short-term schedule. Using scenario analysis, this framework allows the planner to make proactive decisions to achieve the mine's operational and long-term objectives. This paper details the development of simulation and optimization models and presents the implementation of the framework on an iron ore mine case study for verification through scenario analysis.

关键词： Scheduling Simulation optimization Short-term planning Mine operational planning Truck-shovel allocation

Evolution of ferronickel particles during the reduction of low-grade saprolitic laterite nickel ore by coal in the temperature range of 900–1250℃with the addition of CaO–CaF_(2)–H_(3)BO_(3)

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 612-620页

作者： Zulfiadi Zulhan Windu Shalat Metallurgical engineering department Faculty of Mining and Petroleum EngineeringBandung Institute of TechnologyIndonesia

The method of producing ferronickel at low temperature(1250–1400℃)has been applied since the 1950s at Nippon Yakin Kogyo,Oheyama Works,*** was used as an additive to adjust the slag composition for lowering the slag melting *** ferronickel product was recovered by means of a magnetic separator from semi-molten slag and metal after water *** increase the efficiency of magnetic separation,a large particle size of ferronickel is ***,in this study,the influences of CaO,CaF_(2),and H_(3)BO_(3) additives on the evolution of ferronickel particle at≤1250℃were *** experiments were conducted at 900–1250℃with the addition of CaO,CaF_(2),and H_(3)BO_(3).The reduction processes were carried out in a horizontal tube furnace for 2 h under argon *** 1250℃,with the CaO addition of 10 wt%of the ore weight,ferronickel particles with size of 20μm were *** ferronickel particle size increased to 165μm by adding 10 wt%CaO and 10 wt%CaF_(2).The addition of boric acid further increased the ferronickel particle size to 376μm,as shown by the experiments with the addition of 10 wt%CaO,10 wt%CaF_(2),and 10 wt%H_(3)BO_(3).

关键词： saprolitic laterite nickel ore ferronickel particle lime fluorite boric acid

Modeling of flow of oil-in-water emulsions through porous media

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petroleum Science 2015年第2期12卷 273-281页

作者： Ajay Mandal Achinta Bera department of petroleum engineering Indian School of Mines department of Civil & Environmental engineering School of Mining and Petroleum EngineeringUniversity of Alberta

Formation and flow of emulsions in porous media are common in all enhanced oil recovery tech- niques. In most cases, oil-in-water （O/W） emulsions are formed in porous media due to oil-water interaction. Even now, detailed flow mechanisms of emulsions through porous media are not well understood. In this study, variation of rate of flow of O/W emulsions with pressure drop was studied experimentally, and rheological pa- rameters were calculated. The pressure drop increases with an increase in oil concentration in the O/W emulsion due to high viscosity. The effective viscosity of the emulsion was calculated from the derived model and expressed as a function of shear rate while flowing through porous media. Flow of O/W emulsions of different concentrations was evaluated in sand packs of different sand sizes. Emulsions were characterized by analyzing their stability, rheological properties, and tem- perature effects on rheological properties.

关键词： Emulsion Porous media RheologyModeling - Pressure drop

Optimization of Slope Angle and Its Seismic Stability: A Case Study for the Proposed Open Pit Coalmine in Phulbari,NW Bangladesh

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Journal of Mountain Science 2013年第6期10卷 976-986页

作者： Md.Rafiqul ISLAM Mohammed Omar FARUQUE department of petroleum & mining engineering Shahjalal University of Science & Technology

The present study reflects upon the results of substantial program of two-dimensional Finite Element Method （FEM） numerical analyses of the open pit that links to slope angle optimization associated with the safety factor of the pit slope of a coal mine in Bangladesh. In the present analyses, two types of models have been presented. The first model estimates safety factor without seismic effect on the overall pit slope of the model; the second model incorporates safety factor with seismic stability of the model. The calculated optimum slope angle of the first model is 31% with a rational safety factor of 1.51, prior to the seismic effect. However, the value is reduced to 0.93, 0.82, and 0.72, after we applies the seismic effect in the second model with M6, M6.5, and M7, respectively. Finally, our modeling results emphasize that for the case of the proposed Phulbari coalmine, there is extremely high prospect for causing massive slope failure along the optimum pit slope angle with 31% if the mine area felt seismic shaking, like the Sikkim （in northern India） earthquake with M6.9 on September 18, 2011.

关键词： Open pit coalmine Optimum slope angle Safety factor Seismic stability

Revisiting the theoretical prediction of the explosive performance found by the Trauzl test

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Defence Technology（防务技术） 2024年第6期36卷 163-174页

作者： Ivana Dobrilovic Mario Dobrilovic Muhamed Suceska Faculty of mining Geology and Petroleum EngineeringDepartment of Mining Engineering and GeotechnicsUniversity of ZagrebPierottijeva 6Zagreb10000Croatia

The Trauzl lead block test allows the determination of the approximate performance of explosives in blasting applications by measuring the volume increase(expansion)that is produced by the detonation of an explosive charge in the cavity of a lead *** this paper,we reconsider the possibility of interpreting the Trauzl test results in terms of detonation parameters or *** detonation parameters used in the analysis are calculated using the thermochemical code EXPLO5,while the hydrocode AUTODYN is used to simulate the effect of explosive charge density and reaction rate on the results of the Trauzl *** increase in the volume of the lead block cavity was found to correlate best with the product of the detonation heat and the root of the volume of detonation *** simulation showed that the density of explosive charge and the rate of explosive decomposition affect the dynamics of the interaction of the detonation product and the lead block,and consequently the lead block cavity volume increase.

关键词： Trauzl lead block test Performance of explosives EXPLO5 AUTODYN Detonation heat

Optimum mining method selection using fuzzy analytical hierarchy process–Qapiliq salt mine,Iran

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International Journal of mining Science and Technology 2015年第2期25卷 225-230页

作者： Karimnia Hamed Bagloo Heydar department of mining engineering Petroleum and GeophysicsShahrood University of Technology department of mining & Metallurgy engineering Amirkabir University of Technology

mining method selection is the first and the most critical problem in mine design and depends on some parameters such as geotechnical and geological features and economic and geographic factors. In this paper, the factors affecting mining method selection are determined. These factors include shape, thick- ness, depth, slope, RMR and RSS of the orebody, RMR and RSS of the hanging wall and footwall. Then, the priorities of these factors are calculated. In order to calculate the priorities of factors and select the best mining method for Qapiliq salt mine, Iran, based on these priorities, fuzzy analytical hierarchy process （AHP） technique is used. For this purpose, a questionnaire was prepared and was given to the associated experts. Finally, after a comparison carried out based on the effective factors, between the four mining methods including area mining, room and pillar, cut and fill and stope and pillar methods, the stope and nillar mining method was selected as the most suitable method to this mine.

关键词： mining method selection Fuzzy AHP Multiple criteria decision making Salt mine