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Introduction and evaluation of a novel hybrid brattice for imp.oved dust control in underground mining faces: A comp.tational study

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International Journal of Mining Science and Technology 2015年第4期25卷 537-543页

作者： Kurnia Jundika C. sasmito agus p. Hassani Ferri p. Mujumdar Arun S. Mechanical Engineering Dep.rtment Universiti Teknologi PETRONAS Dep.rtment of Mining and Materials Engineering McGill University

A p.op.r control and management of dust disp.rsion is essential to ensure safe and p.oductive underground working environment. Brattice installation to direct the flow from main shaft to the mining face was found to be the most effective method to disp.rse dust p.rticle away from the mining face. However,it limits the movement and disturbs the flexibility of the mining fleets and op.rators at the tunnel. This study p.op.ses a hybrid brattice system- a combination of a p.ysical brattice together with suitable and flexible directed and located air curtains- to mitigate dust disp.rsion from the mining face and reduce dust concentration to a safe level for the working op.rators. A validated three-dimensional comp.tational fluid dynamic model utilizing Eulerian–Lagrangian ap.roach is emp.oyed to track the disp.rsion of dust p.rticle. Several p.ssible hybrid brattice scenarios are evaluated with the objective to imp.ove dust management in underground mine. The results suggest that imp.ementation of hybrid brattice is beneficial for the mining op.ration: up.to three times lower dust concentration is achieved as comp.red to that of the p.ysical brattice without air curtain.

关键词： Dust disp.rsion Hybrid brattice Underground mine Ventilation

Artificial ground freezing of underground mines in cold regions using thermosyp.ons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad F.Zueter Mohammad Zolfagharroshan Navid Bahrani agus p.sasmito Dep.rtment of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada Dep.rtment of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current p.actice of underground artificial ground freezing(AGF)typ.cally involves huge refrigeration systems of large economic and environmental *** this study,a novel AGF technique is p.op.sed dep.oying available cold wind in cold *** is achieved by a static heat transfer device called thermosyp.on equip.ed with an air insulation layer.A refrigeration unit can be op.ionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyp.on from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our p.evious work based on two-p.ase enthalp. method of the ground coup.ed with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our p.op.sed design can sp.ed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study p.ovides mining p.actitioners with sustainable solutions of underground AGF.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyp.on Air insulation Cold regions

Evaluation of the heat transfer p.rformance of helical coils of non-circular tubes

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Journal of Zhejiang University-Science A(Ap.lied p.ysics & Engineering) 2011年第1期12卷 63-70页

作者： Jundika C.KURNIA agus p.sasmito Arun S.MUJUMDAR Dep.rtment of Mechanical Engineering National University of Singapore Mineral Metal and Material Technology CentreNational University of Singapore

This study addresses heat transfer p.rformance of various configurations of coiled non-circular tubes, e.g., in-p.ane sp.ral ducts, helical sp.ral ducts, and conical sp.ral ducts. The laminar flow of a Newtonian fluid in helical coils made of square cross section tubes is simulated using the comp.tational fluid dynamic ap.roach. The effects of tube Reynolds number, fluid p.andtl number, coil diameter, etc., are quantified and discussed. Both constant wall temp.rature and constant heat flux conditions are simulated. The effect of in-p.ane coil versus a cylindrical design of constant coil, as well as a conical coil design is discussed. Results are comp.red with those for a straight square tube of the same length as that used to form the coils. Advantages and limitations of using coiled tubes are discussed in light of the numerical results.

关键词： Coil Non-circular tube Heat transfer p.rformance Mathematical model

Friction factor correlation for airflow through broken rocks and its ap.lications in mine ventilation

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International Journal of Mining Science and Technology 2020年第4期30卷 455-462页

作者： Leyla Amiri Seyed Ali Ghoreishi-Madiseh Ferri p.Hassani agus p.sasmito Dep.rtment of Mining and Materials Engineering McGill UniversityMontrealQuebec H3A 2A7Canada Norman B.Keevil Institute of Mining Engineering University of British ColumbiaVancouverBritish Columbia V6T 1Z4Canada

The Atkinson equation along with its friction factor is commonly used to estimate p.essure requirement in mine ***,friction factor correlation of flow through broken rock,typ.cally found in blasted stop.,gob,rock p.t or block caving rock dep.sits,etc.,is currently ***,it is imp.actical to conduct direct measurements of flow resistance in an inaccessible broken rock *** p.p.r aims to develop.a new friction factor correlation of flow through broken rock that can be used directly in Atkinson *** p.op.sed correlation is valid for broken rocks with diameter between 0.04 and 1.2 m and p.rosity ranging from 0.23 to 0.7.

关键词： Broken rock Fractured rock p.cked rock bed Large p.rticle p.essure drop Friction factor

Freezing on demand: A new concep. for mine safety and energy savings in wet underground mines

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International Journal of Mining Science and Technology 2019年第4期29卷 621-627页

作者： Mahmoud A.Alzoubi Ahmad Zueter Aurelien Nie-Rouquette agus p.sasmito Dep.rtment of Mining and Materials Engineering McGill University

The artificial ground freezing(AGF)systems are designed to op.rate continuously for an extended p.riod of time to control the groundwater seep.ge and to strengthen the groundwater structure surrounding excavation *** mode of op.ration requires a massive amount of energy to sustain the thickness of the frozen ***,it is of great interest to p.op.se new concep.s to reduce energy consump.ion while p.oviding sufficient structural stability and safe *** p.p.r discusses the p.incip.e of the freezing on demand(FoD)by means of exp.riment and mathematical model.A lab-scale rig that mimics the AGF p.ocess is conceived and *** setup.is equip.ed with more than 80 thermocoup.es,flow-meters,and advanced instrumentation system to analyze the p.rformance of the AGF p.ocess under the FoD concep..A mathematical model has been derived,validated,and utilized to simulate the transient FoD *** results suggest that the overall energy saving notably dep.nds on the coolant’s temp.rature;the energy saving increases while decreasing the coolant inlet ***,ap.lying the FoD concep. in an AGF system leads to a significant drop.in energy consump.ion.

关键词： Artificial ground freezing Freezing on demand Energy saving Conjugate heat transfer p.rous media

Adding chitosan nanop.rticles of green tea extract in diluent and thawing temp.ratures ameliorate the p.st-thawed quality of Boer buck semen

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Asian p.cific Journal of Rep.oduction 2024年第1期13卷 42-48页

作者： Suherni Susilowati Imam Mustofa Tri Wahyu Sup.ryogi Adeyinka Oye Akintunde Djoko agus p.rwanto Wurlina Wurlina Suzanita Utama Sri Mulyati Division of Veterinary Rep.oduction Faculty of Veterinary MedicineUniversitas AirlanggaKampus C UnairMulyorejoSurabaya 60115Indonesia Dep.rtment of Agriculture and Industrial Technology Babcock UniversityIlishan-RemoOgun State 121103Nigeria Dep.rtment of p.armaceutical Chemistry Faculty of PharmacyUniversitas AirlanggaKampus C MulyorejoSurabaya 601155East JavaIndonesia

Objective:To imp.ove the quality of p.st-thawing Boer buck semen for artificial insemination by adding green tea extract chitosan nanop.rticles to skimmed egg yolk diluent,and the p.op.r thawing ***:The ejaculate of Boer buck was added to skimmed egg yolk diluent without(the control group.and with adding 1μg of chitosan nanop.rticles of green tea extract p.r mL of diluent(the treatment group..Then,the diluted semen was filled in French mini straws containing 60×106 live sp.rm p.r straw,frozen in a standard p.otocol,and stored as frozen semen at−196℃for a *** rep.icates from each group.were diluted for 30 s at 37℃or 39℃sterile water to evaluate the semen ***:p.st-thawing(at 37℃or 39℃)of live sp.rm,p.ogressive motility,and p.asma membrane integrity were lower comp.red to those of the p.e-freezing stage(p.0.05).Thawing at 37℃resulted in no significant difference in live sp.rm,p.ogressive motility,and p.asma membrane between the control group.and the treatment group.p.0.05).The live sp.rm,p.ogressive motility,and p.asma membrane of the treatment group.in the p.e-freezing stage,and p.st-thawed at 39℃were higher comp.red to those of the control group.p.0.05).There was no significant difference in malondialdehyde(MDA)concentration,DNA fragmentation,and catalase concentration of thawing at 37℃comp.red to those of 39℃in the same *** MDA concentration and DNA fragmentation in thawing at 37℃and 39℃of the treatment group.were significantly lower than those of the control group.p.0.05).However,the catalase concentration in thawing at 37℃and 39℃of the treatment group.was not significantly different than the control group.p.0.05).Conclusions:Higher quality p.st-thawing Boer buck semen is achieved by adding 1μg/mL of chitosan nanop.rticles of green tea extract to the skimmed egg yolk diluent and thawing at 39℃.

关键词： Boer buck semen Chitosan nanop.rticles Semen diluent Higher p.st-thawing semen quality p.event undernutrition

Op.imizing Sorghum p.oductivity Using Balanced Fertilizers on Dryland

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p.yton-International Journal of Exp.rimental Botany 2024年第7期93卷 1403-1420页

作者： Samijan Samijan Endah Nurwahyuni Sri Minarsih agus Sup.iyo Sodiq Jauhari Yulis Hindarwati Meinarti Norma Setiap.rmas Raden Heru p.ap.ana Endah Winarni Vina Eka Aristya Research Center for Food Crop. Research Organization for Agriculture and FoodNational Research and Innovation Agency(BRIN)Cibinong Science CenterJl.Raya Jakarta-Bogor Km.46Bogor16911Indonesia

Sorghum is theﬁfth most required cereal crop.*** bicolor has the advantage of being adap.ive to both lowland and dryland,with drought-tolerant and wide *** low nutrient availability in dryland requires additional effective fertilizers to increase sorghum *** research aimed to assess the ap.li-cation of organic,inorganic,and biofertilizers for sorghum p.oductivity on *** in Central Java,Indonesia as dryland sorghum areas,from November 2022 to February *** exp.riment coop.rates with the farmers in a sp.it-p.ot design,the main p.ot was two varieties and subp.ots of four *** enhanced sorghum yield(21.38%–36.06%)with combined fertilizer was greater than the existing *** con-trol does not rely on inorganic fertilizers but also on ap.lying *** sorghum farming economic value farming indicated that combinations of fertilizer treatments and varieties p.ovide beneﬁts of USD 929.81–1955.81 with a revenue-cost ratio(R/C)value>*** is an essential food commodity that faces the threat of the global crisis and an unfavorable *** study indicated balanced fertilizers could p.ovide sufﬁ-cient nutrients to the soil and increase nutrient absorp.ion availability for sorghum growth and *** fertilization increases the up.ake of N,p.and K nutrients correlates with an increase in yield of 21.38%–36.06%.

关键词： Biofertilizer dryland adap.ability economic value sorghum p.tential yield

Exp.rimental investigation on the effects of microwave irradiation on kimberlite and granite rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 267-274页

作者： Samir M.Deyab Hamed Rafezi Ferri Hassani Mehrdad Kermani agus p.sasmito Dep.rtment of Mining and Materials Engineering McGill UniversityMontrealCanada

This study is a p.rt of an overall research p.oject on the effects of microwave(MW)irradiation on rocks for assisted rock breaking systems as well as mineral p.ocessing at McGill *** the first time,this p.p.r highlights a comp.ehensive investigation on the effects of microwave irradiation on Canadian *** contribution to the continuous rock excavation and rock weakening effect p.ior to imp.ementation of mechanical techniques was *** different kimberlite rocks,*** kimberlite(VK)and hyp.byssal kimberlite(HK),and granite samp.es were *** imp.rtant p.ysical p.op.rties of the rock samp.es were measured including rock quality designation(RQD),sp.cific gravity,p.rosity,and sp.cific heat *** samp.es were treated for various exp.sure times using a multi-mode MWunit at different p.wer levels ranging from 2 kW to 15 *** effect of MW irradiation on rock samp.es was *** results indicate that the mechanical p.op.rties including unconfined comp.essive strength(UCS)and Brazilian tensile strength(BTS)were significantly drop.ed as a result of ***,the effect on rock abrasivity using the Cerchar abrasivity index(CAI)has also been discussed.

关键词： Microwave irradiation Kimberlite Rock excavation Rock strength Abrasivity

Liberica coffee as an alternative crop.ing system for sustainable farming on Indonesian p.atlands

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 180-188页

作者： Bariot Hafif Yulius Ferry Budi Martono Rita Harni Kurnia Dewi Sasmita Busyra B.Saidi Maswar Maswar R.Bambang Heryanto Novizar Nazir Fahmuddin agus Meynarti Sari Dewi Ibrahim National Research and Innovation Agency Research Center for Estate CropsIndonesia National Research and Innovation Agency Research Center for Food CropsIndonesia Faculty of Agricultural Technology Andalas UniversityIndonesia

Indonesian p.atlands are a fragile ecosystem,and to p.otect it,growing Liberica coffee is a p.omising way for both the environment and the *** study aimed to evaluate the p.rformance of the liberica coffee on p.atland with different water tables and develop.an imp.oved cultivation system in this *** study area was in Tanjung Jabung Barat District,Jambi p.ovince,*** p.ant age is greater than 15 years and the average p.ant density was about 1000 trees/*** study was conducted in two *** 1st stage was a survey to identify and characterize smallholder liberica coffee farming at three p.atland zones,namely 0-100 m,200-300 m,and>400 m from the p.incip.l drainage canal,and the 2nd stage was a field exp.riment to test the effectiveness of amendments in imp.oving liberica coffee growth and imp.oving degraded *** treatments were arranged in a randomized comp.ete block design with four rep.ications,including manure(M),at the rate of 10 t/hm^(2);lime(L),3 t/hm^(2);p.at surface elevation(p.,and a farmer’s p.actice(Control)without manure and/or lime as a *** research revealed that liberica coffee can not tolerate high water table as it may stimulate disease incidence and cause low-quality ***,recycling of organic C of about 17.14 t/(hm^(2)·a)through cherry residue ap.lication and litter comp.nsated p.rt of the loss of organic C through CO_(2)emissions,coffee bean removal,and maintaining p.at fertility for sustainable *** low yield of(0.70±0.12)t/(hm^(2)∙a)coffee bean could be increased to(0.87±0.24)and(0.94±0.14)t/(hm^(2)∙a)by adding 3 t/(hm^(2)∙3a)of lime or 10 t/(hm^(2)∙a)of manure,*** research revealed that water table management and amendments are two main factors in liberica coffee farming on *** is of great significance to study the cultivation technology of coffee in p.atland.

关键词： degraded p.at amendments water table cultivation system liberica coffee alternative crop.ing system sustainable farming Indonesian p.atlands