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Laboratory investigation into the use of soundless chemical demolitions agents for the breakage of hard rock

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International Journal of Coal Science & Technology 2022年第5期9卷 71-80页

作者： Kelly‑Meriam Habib Isaac Vennes hani Mitri Department of Mining and Material Engineering McGill UniversityMontrealCanada

The method of drilling and blasting with explosives is widely used in rock fragmentation applications in the mining industry for mine development and ore ***,the use of explosives is associated with rigorous safety and environmental constraints as blasting creates toxic fumes,ground vibrations,and *** study is focused on the use of Soundless Chemical Demolition Agents(SCDA)as a more environmentally friendly method for rock breakage and a potential replacement of *** this paper,the results of a series of experimental tests are reported to identify the efect of SCDA on hard rock breakage under no load and under uniaxial loading *** granite prismatic specimens of 152.4 mm(6″)×152.4–203.2 mm(6–8″)×406.4 mm(16″)are used to test the infuence of borehole size on the time to fracturing with SCDA borehole size of 25.4 mm(1″),31.75 mm(1.25″)and 38.1 mm(1.5″).It is shown that the fracturing time decreases with increasing borehole *** is also shown that specimens subjected to uniaxial compression of 5 MPa fracture as early as 7 h after SCDA mixing.A borehole spacing to borehole diameter ratio of 12.8 to 14.6 is suggested for practical applications.

关键词： Explosive-free Hard rock fragmentation Soundless chemical demolition agents Uniaxial loading

Methodology for the estimation of expansive cement borehole pressure

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International Journal of Mining Science and Technology 2023年第1期33卷 73-81页

作者： Kelly-Meriam Habib Isaac Vennes hani S.Mitri Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0E8Canada

This work is part of a multi-phase project which aims to develop a sound methodology for rock fragmen-tation in underground mines using expansive *** specifically,it is the first phase of the project which focuses on laboratory tests to investigate the mechanical performance of expansive cement,also known as soundless chemical demolition agents(SCDA).This paper reports the results of laboratory tests conducted on instrumented thick-walled cylinders filled with expansive *** pressure evo-lution and temperature variation with time are first examined for different borehole *** clas-sical analytical method for expansive pressure estimation is validated with direct pressure measurement using high-capacity pressure sensor,and an empirical model is obtained.A new methodology based on iterative procedure is developed using axisymmetric finite element modelling and test results to derive the modulus of elasticity of the expansive cement at peak *** results of this study show that the expansive pressure increases with borehole diameter when the rigidity of the steel cylinder is constant reaching 83 MPa for a 38.1 mm *** is also shown that the expansive pressure decreases signif-icantly with increased cylinder rigidity for the same borehole *** newly developed methodol-ogy revealed that the modulus of elasticity of expansive cement at peak pressure is estimated at 8.2 GPa.A discussion on the extension of the findings of this work to hard rock mining applications is presented.

关键词： Rock fragmentation Soundless chemicaldemolitionagents Expansive cement

Numerical modeling of destress blasting for strata separation

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2238-2249页

作者： Petr Konicek Tuo Chen hani S.Mitri Institute of Geonics Czech Academy of SciencesOstrava70800Czech Republic Department of Mining and Materials Engineering McGill UniversityMontrealH3A 0E8Canada

Destress blasting(DB)implemented along the perimeter of safety pillars is a special application of destressing in coal longwall *** goal is to separate relatively more deformed mined areas from safety pillars,such as shaft pillars or cross-cut pillars,to reduce the transfer of high stresses to the protective *** case study aims to numerically simulate selected destress blasts in the Czech part of the Upper Silesian Coal Basin and examine its impact on stress transfer to the safety pillar *** separate the area between the protective pillar and the longwall(LW),two fans of five 93-mm blast holes(length of 93e100 m)were drilled from the gate roads into the overburden *** set of blast holes was fired separately in two stages without time *** explosive charge(gelatin-type of explosive)of each stage is 3450 *** two DB stages were fired when the longwall face was approximately 158 m and 152 m away from the blast.A 3D mine-wide model is built and validated with in situ stress measured with *** and destressing in three 5-m thick coal seams are simulated in the *** modeling of DB is successfully conducted using a rock fragmentation factor a of 0.05 and a stress reduction/dissipation factor β of *** of transfer of additional stress from the mining area into the safety pillar is evaluated by comparison of yielding volume before and after *** is shown that yielding volume drops after DB by nearly 80%in the area of the destressing panel and near the safety shaft pillar.

关键词： Rockburst hazard Destress blasting(DB) Strata separation Safety pillar Numerical modeling Fragmentation factor Stress dissipation factor Longwall mining

Numerical modelling of spatially and temporally distributed on‑fault induced seismicity:implication for seismic hazards

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International Journal of Coal Science & Technology 2023年第1期10卷 108-123页

作者： Atsushi Sainoki Adam Karl Schwartzkopf Lishuai Jiang hani Mitri Faculty of Advanced Science and Technology KumamotoUniversityKumamotoJapan School of Engineering The University of Western AustraliaPerthAustralia State Key Laboratory of Mining Disaster Preventionand Control Shandong University of Scienceand TechnologyShandongChina Department of Mining and Materials Engineering McGillUniversityMontrealCanada

Induced seismicity is strongly related to various engineering projects that cause anthropogenic in-situ stress change at a great ***,there is a need to estimate and mitigate the associated *** the past,various simulation methods have been developed and applied to induced seismicity analysis,but there is still a fundamental diference between simulation results and feld observations in terms of the spatial distribution of seismic events and its *** present study aims to develop a method to simulate spatially distributed on-fault seismicity whilst reproducing a complex stress state in the fault ***,an equivalent continuum model is constructed,based on a discrete fracture network within a fault damage zone,by employing the crack tensor theory.A fault core is simulated at the center of the model as a discontinuous *** the model,a heterogeneous stress state with stress anomalies in the fault zone is frst simulated by applying tractions on the model outer ***,the efective normal stress on the fault plane is decreased in a stepwise manner to induce *** simulation result is validated in terms of the b-value and other seismic source parameters,hence demonstrating that the model can reproduce spatially and temporally distributed on-fault *** analysis on the parameters shows the variation of frequency-magnitude distribution before the occurrence of large seismic *** variation is found to be consistent with feld observations,thus suggesting the potential use of this simulation method in evaluating the risk for seismic hazards in various engineering projects.

关键词： Induced seismicity Fracture network Fault damage zone Crack tensor theory

经颅磁刺激联合醒脑开窍针对脑卒中患者神经功能及认知功能的影响

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中国中医急症 2024年第3期33卷 465-468页

作者：金倩倩俞红王哈妮浙江康复医疗中心康复评定与治疗中心浙江杭州310051

目的探究经颅磁刺激联合醒脑开窍针对脑卒中患者神经功能及认知功能的影响。方法选取76例脑卒中患者,随机分为治疗组与对照组各38例。两组均接受常规对症处理,在此基础上,治疗组予以经颅磁刺激联合醒脑开窍针治疗,而对照组仅予经颅磁刺... 详细信息

目的探究经颅磁刺激联合醒脑开窍针对脑卒中患者神经功能及认知功能的影响。方法选取76例脑卒中患者,随机分为治疗组与对照组各38例。两组均接受常规对症处理,在此基础上,治疗组予以经颅磁刺激联合醒脑开窍针治疗,而对照组仅予经颅磁刺激治疗,两组均治疗6周。分别于治疗前后进行神经递质指标[P物质(SP)、神经肽Y(NPY)、5-羟色胺(5-HT)]水平检测,并记录神经功能、认知功能、日常生活能力以及中医证候积分,同时于疗程结束后评价临床疗效并观察不良反应。结果治疗后,治疗组的总有效率高于对照组(P0.05)。两组各项中医证候积分、NIHSS评分以及SP、NPY水平均明显降低,且治疗组较对照组更低(P<0.01)。两组MoCA、BI评分以及5-HT水平均明显升高,且治疗组较对照组更高(P<0.01)。结论经颅磁刺激联合醒脑开窍针能够显著改善脑卒中患者的神经功能和认知功能,并对神经递质含量具有良好调节作用,疗效显著且安全性高。

关键词：脑卒中经颅磁刺激针刺醒脑开窍针神经功能认知功能

Dry Fiber‑Based Electrodes for Electrophysiology Applications

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Advanced Fiber Materials 2023年第3期5卷 819-846页

作者： Ladan Eskandarian Elmira Pajootan Amirali Toossi hani E.Naguib Department of Materials Science and Engineering University of TorontoTorontoON M5S 3E4Canada Department of Chemical Engineering McGill UniversityMontrealQC H3A 0C5Canada Research and Development Department Myant IncTorontoON M9W 1B6Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoON M5S 3G8Canada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoON M5S 3G8Canada

Long-term continuous health care monitoring,using wearable technologies has received considerable interest due to the significant contribution of wearables to the diagnosis of diseases and identification of health *** have been widely applied in human societies due to their unique advantages,including stretchability,small diameters,high dynamic bending elasticity,high length-to-width ratios,and mechanical strength.A new generation of fiber-based electrodes is being integrated into smart textiles and wearables for continuous long-term biosignal *** fiber-based electrodes are breathable,flexible,and durable,unlike conventional disposable gel electrodes,which are difficult to employ for long-term applications because of skin irritation and allergic responses caused by their moist and adhesive interface with the *** this review,we provide a concise summary of recent breakthroughs in the design,and manufacturing of dry fiber-based electrodes for electrophysiology applications,with a particular emphasis on applications in electrocardiography,electromyography,and *** on numerous features of electroactive fiber materials,fiber processing,electrode fabrication,scaled-up manufacturing,standardization of testing and performance criteria,we discuss current limitations and provide an outlook for the future development of this field.

关键词： Electroactive fiber Smart textiles Electrocardiography Wearables Health care monitoring Textile

Behavior of traditional concrete dams and three-dimensional printed concrete dams under the debris flow impact

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Journal of Mountain Science 2023年第12期20卷 3703-3717页

作者： MEREE hani YAN Shuai-xing WANG Dong-po BI Yu-zhang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China

This study investigated the resilience of traditional concrete dams compared to 3D printed concrete dams(3DPC)when subjected to debris *** types of dams,namely check dams,arch dams,and curve dams,were numerically analyzed using a three-dimensional Coupled Eulerian-Lagrangian(CEL)*** research focused on critical factors such as impact force and viscous energy dissipation to compare dam ***,the study examined the printing and service phases of 3DPC models,determining potential failure modes and analyzing printing *** results demonstrated that 3DPC dams outperformed traditional concrete dams,with filament deposition orientation,perpendicular to the debris flow direction,identified as a pivotal *** percentage and pattern were also found to influence the behavior of 3DPC ***,curved dams exhibited superior performance based on dam *** findings have significant potential for advancing the development of resilient dam structures capable of withstanding debris flow impacts.

关键词： Dam geometry Impact force Printing process Viscous dissipation Coupled Eulerian-Lagrangian Three-dimensional printed concrete

Short-term outcomes of single-incision compared to multi-port laparoscopic gastrectomy for gastric cancer:A meta-analysis of randomized controlled trials

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Laparoscopic, Endoscopic and Robotic Surgery 2023年第4期6卷 127-133页

作者： Sameh Hany Emile Samer hani Barsom General Surgery Department Mansoura University HospitalsMansoura Egypt Internal Medicine Department University of South DakotaSanford School of MedicineSouth DakotaUSA

Objective:Single-incision laparoscopic sugery has emerged as a safe and less invasive approach to conventional multi-port *** present meta-analysis aimed to assess the collective outcomes of single-incision laparoscopic gastrectomy(SILG)compared to multi-port laparoscopic gastrectomy(MLG)for gastric ***:A PRISMA-compliant systematic review of randomized controlled trials(RCTs)that compared SILG and MLG for gastric cancer in PubMed and Scopus through January 2023 was *** main outcomes of the review were complications,postoperative pain,conversion to open surgery,hospital stay,and ***:Three RCTs including 301 patients(61.8%male)were incuded.A total of 151 patients underwent SILG,and 150 underwent *** was associated with a shorter operative time(WMD=-16.39,95%CI:=27.38 to=5.40,p=0.003;2=0%)and lower pain scores at postoperative day 3(WMD=-1.18,95%CI:=2.27 to=0.091,p=0.033;I^(2)=99%)than *** were no statistically significant differences between the two groups in es timated blood loss(WMD=-16.95,95%CI:-35.84 to 1.95,p=0.078;I^(2)=82%),complications(OR=0.71,95%Cl:0.36 to 1.42,p=0.337;I^(2)=0%),conversion to open surgery(OR=0.33,95%C:0.01 to 8.38,p=0.504),hospital stay(WMD=0.72,95%CI:-0.92 to 2.36,p=0.056;P=84%),time to first flatus(WMD=0.06,95%CI:=0.14 to 0.26,p=0.566;I^(2)=0%),time to first defecation(WMD=-0.14,95%CI:=0.46 to 0.18,p=0.392;I^(2)=0%),or time to first oral intake(WMD=0.37,95%a:=0.75 to 1.49,p=0.520;I^(2)=94%).Conclusions:SILG is associated with shorter operative times and less early postoperative pain than *** odds of complications,blood loss,hospital stay,and gastrointestinal recovery were similar between the two procedures.

关键词： Single-incision Laparoscopic Gastrectomy Meta-analysis Randomized trials

Rheological and Morphological Characterization of Modified Bitumen with Cup Lump Rubber

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Journal of Renewable Materials 2023年第5期11卷 2433-2451页

作者： Mohammed Albuaymi Suleiman Abdulrahman Fayez Alanazi hani Alanazi Musa Adamu Department of Civil and Environmental Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Civil Engineering Kebbi State University of Science and TechnologyAlieroKebbiNigeria School of Civil Engineering Universiti Teknologi MalaysiaJohor Bahru81310Malaysia Department of Civil Engineering College of EngineeringJouf UniversitySakaka72388Saudi Arabia Engineering Management Department College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Civil Engineering Bayero UniversityKanoPMB 3011Nigeria

Pure bitumen is not suitable for heavy traffic loads;hence modifiers are used to improve the bitumen ***,cup lump rubber(CLR)has become a preferred modifier due to its outstanding performance and less ***,little is known about the interactions between CLR and ***,this study investigates the behavior of bitumen with *** percentages of CLR(2.5%,5.0%,7.5%,and 10.0%by weight of bitumen)were used to modify conventional 60/70 penetration grade *** modified bitumen was evaluated through different laboratory testing such as dynamic shear rheometer,rotational viscosity,softening point,bending beam rheometer,ductility,and elastic *** testing results show that the addition of CLR increased the bitumen’s rutting resistance by 3 PG grades at high *** low pavement temperatures,the cup lump rubber modified bitumen(CMB)can withstand up to−34℃.Fourier Transform Infrared(FTIR)analysis shows that the Aromaticity index at 1600 cm^(−1) rose as the CLR percentage increased,indicating the formation of a binder with a compact *** is expected to improve the elasticity of bitumen throughπ-π*** Force Microscopy(AFM)results showed the Catana phase increased in size and quantity at 5.0%and 7.5%CLR *** contact angle measurement revealed that the binders are hydrophobic and tend to repel the dropped water on the bitumen surface.

关键词： Cup lump rubber polymer modified bitumen hydrophobicity natural rubber