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Physio-biochemical and nutrient constituents of peanut plants under bentazone herbicide for broad-leaved weed control and water regimes in dry land areas

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Journal of Arid Land 2020年第4期12卷 630-639页

作者： hani s saudy Ibrahim M EL–METWALLY Goma A ABD EL–sAMAD Agronomy Department Faculty of AgricultureAin Shams University68–Hadayek Shoubra 11241CairoEgypt Botany Departments National Research CentreEl–Behos St.Dokki 12622CairoEgypt

The abundance of broad-leaved weeds in peanut fields represents the handicap in weed management programs, since limited specific herbicides can be recommended to control them. Moreover, the physio-biochemical constituents and nutritional status in peanut plants as affected by available herbicides, i.e., bentazone under water stress conditions are not well known. Therefore, field trials were conducted during the growing seasons in 2016 and 2017 to investigate the interactional impact of irrigation levels(I_(50), I_(75) and I_(100), representing irrigation by 50%, 75% and 100% of crop evapotranspiration, respectively) and weed control practices(bentazone, bentazone+hoeing once, hoeing twice and weedy check as control) on dominant broad-leaved weeds as well as peanut physiological and agronomic traits. Result indicated that the efficiency of weed control for each weeded treatment under I_(50) significantly equaled with its counterpart under I_(75) or I_(100). Bentazone+hoeing once diminished weed biomass by 89.3% and enhanced chlorophyll content of peanut plants by 51.2%. Bentazone relatively caused a reduction in carotenoides. Hoeing twice and bentazone+hoeing once under I_(100) in both growing seasons as well as hoeing twice under I_(75) in 2017 were the superior combinations for boosting pod yield of peanut plants. Treatment of bentazone+hoeing once and I_(75) recorded the lowest reduction in N utilization percentage and the highest increase in potassium utilization percentage of peanut plants. Eliminating weeds enhanced water use efficiency by 37.8%, 49.6% and 34.7% under I_(50), I_(75) and I_(100), respectively. In conclusion, peanut seems to be tolerant to bentazone at moderate water supply, thus it can be safely used in controlling the associated broad-leaved weeds.

关键词： biochemical traits drought nutritional status peanut productivity weed growth

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strategic sill pillar design for reduced hanging wall overbreak in longhole mining

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International Journal of Mining science and Technology 2021年第5期31卷 975-982页

作者： Tuo Chen hani s.Mitri Department of Mining and Materials Engineering Mc Gill UniversityMontrealQuebec H3A 0E8Canada

steeply dipping,vein and tabular orebodies are traditionally extracted with longitudinal retreat mining methods such as Eureka and Avoca in a bottom-up sequence with delayed *** increase productivity,sill pillars in the orebody are used to separate mining zones thus allowing production to take place simultaneously in two or more *** such mining methods are productive,they may be accompanied with high volumes of hanging wall overbreak causing significant unplanned ore *** this work,it is shown through a mine design case study of a narrow vein deposit that a sill pillar could also play a significant role in limiting hanging wall *** demonstrate the role of sill pillar,a novel numerical modelling scheme is proposed to account for progressive stope wall overbreak.A numerical modelling approach of element death and rebirth is developed to allow for the detected stope overbreak to be immediately removed and replaced with backfill material before upper-level stope *** is further shown that the average overbreak volume could be reduced by as much as 33%when the sill pillar is strategically placed in the lower half of a mine plan.

关键词： Underground mine design Longitudinal mining sill pillar design Unplanned ore dilution Numerical modelling

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Numerical investigation into pillar failure induced by time-dependent skin degradation

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International Journal of Mining science and Technology 2017年第4期27卷 591-597页

作者： sainoki Atsushi Mitri hani s. Department of Mining and Materials Engineering McGill University Montreal H3A0E8 Canada

This paper focuses on the instability mechanism of an isolated pillar, caused by time-dependent skin degradation and strength heterogeneity. The time-dependent skin degradation is simulated with a non-linear rheological model capable of simulating tertiary creep, whereby two different pillar failure cases are investigated. The first case is of an isolated pillar in a deep hard rock underground mine and subjected to high stresses. The results show that pillar degradation is limited to the regions near the surface or the skin until two months after ore extraction. Afterwards degradation starts to extend deeper into the pillar, eventually leaving a highly-stressed pillar core due to stress transfer from the failed *** potential indices show that the risk increases exponentially at the core as time goes by. It is then demonstrated that the progressive skin degradation cannot be simulated with conventional strain-softening model assuming brittle failure. The parametric study with respect to the degree of heterogeneity reveals that heterogeneity is key to the occurrence of progressive skin degradation. The second case investigated in this study is pillar failure taking place in a very long period. such failure becomes significantly important when assessing the risk for ground subsidence caused by pillar collapse in an abandoned mine. The analysis results demonstrate that the employed non-linear rheological model can simulate gradual skin degradation taking place over several hundred years. The percentage of damage zone volume within the pillar is merely 1% after a lapse of one days and increases to 50% after one hundred years, indicating a high risk for pillar collapse in the long term. The vertical displacements within the pillar also indicate the risk of subsidence. The proposed method is suitable for evaluating the risk of ground surface subsidence above an abandoned mine.

关键词： Pillar stability Underground mine skin degradation Rheological model Time-dependent failure

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Guest Editorial-special issue on advances in mine safety science ＆ engineering

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International Journal of Mining science and Technology 2017年第4期27卷 589-590页

作者： Mitri hani s. Department of Mining and Materials Engineering McGill University Montreal H3A 0E8 Canada

Mine safety encompasses many aspects of a mining operation,ranging from personnel and equipment safety to the safety of the *** disasters such as fires,floods,explosions,outbursts,rockbursts,ground caving,pit slope sl... 详细信息

关键词： in is as of Guest Editorial-special issue on advances in mine safety science engineering been on

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Determination of mining-induced stresses using diametral rock core deformations

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International Journal of Coal science & Technology 2022年第6期9卷 13-24页

作者： Yizhuo Li hani s.Mitri Department of Mining and Materials Engineering McGill UniversityMontrealCanada

Knowledge of ground stresses is crucial for ground control activities such as the design of underground openings,selec-tion of support systems,and analysis for ***,it is a known fact that far field stresses experience changes in orientation and magnitude due to the presence of geological structures and due to the excavations created by mining *** a result,in-situ stresses around drifts,ramps,and stopes in underground mines are quite different from far field or pre-mining *** purpose of this research is to develop a simple and practical methodology for determining in-situ *** relief occurs once the rock core is drilled *** relief is a function of the surrounding stress *** study uses exploration rock cores that are drilled off for the purpose of orebody definition in the underground *** method measures and analyzes the diametral core deformations in *** case studies from operating underground mines are presented for *** these case studies,rock core deformations are measured with a customized test apparatus and rock samples were prepared and tested for Young's modulus and Poisson's *** differential stress,namely the difference between the local principal stresses in the plane perpendicular to the core rock axis is *** is shown that this methodology is useful for determining the brittle shear ratio in the rock mass,which is of primary interest to ground control studies.

关键词： In-situ stresses Rock core diametral deformation strain relief Core-based stress measurement Brittle shear ratio

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Quantitative analysis with plastic strain indicators to estimate damage induced by fault-slip

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 1-10页

作者： Atsushi sainoki hani s.Mitri International Research Organization for Advanced science and Technology Kumamoto University Department of Mining and Materials Engineering McGill University

In the present study, methodologies to evaluate damage around an underground opening due to seismic waves arising from mining-induced fault-slip are examined. First, expressions for an associated flow rule with a failure criterion are developed for biaxial stress conditions, which are implemented into FLAC3D code. A three-dimensional(3D) mine model encompassing a fault running parallel to a steeply dipping orebody is constructed, whereby static and dynamic analyses are performed to extract stopes and simulate fault-slip in dynamic condition, respectively. In the analysis, the developed biaxial model is applied to the stope wall. The fault-slip simulation is performed, considering shearing of fault surface asperities and resultant stress drop driving the fault-slip. Two methodologies to evaluate damage caused by seismic waves arising from the simulated fault-slip are examined:(i) the ratio of dynamic plastic strain increment to elastic strain limit and(ii) plastic strain energy density. For the former one, two types of strain increments are tested, namely effective shear strain increment and volumetric strain *** results indicate that volumetric strain increment is a suitable index for detecting damage near the stope wall, while effective shear strain increment is appropriate for evaluating damage in backfill. The evaluation method with plastic strain energy density is found to be capable of assessing damage accumulated in an extensive area caused by rock mass oscillation due to seismic wave propagation. Possible damage to mine developments in the proximity of a stope is clearly described with the index. The comparison of the two methods clarifies that the former one assesses "instantaneous" damage, which is found to be different from "accumulated" damage calculated using plastic strain energy density, in terms of damage area and its location. It is thus concluded that the combination of the two methodologies leads to more accurate damage assessment as a pr

关键词： stability of mine opening Mining-induced fault-slip seismic waves Biaxial stress condition

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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

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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

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Volumetric analysis of rock mass instability around haulage drifts in underground mines

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 60-71页

作者： shahé shnorhokian Bryce MacNeil hani s.Mitri Department of Mining and Materials Engineering McGill University

Haulage networks are vital to underground mining operations as they constitute the arteries through which blasted ore is transported to surface. In the sublevel stoping method and its variations, haulage drifts are excavated in advance near the ore block that will be mined out. Numerical modeling is a technique that is frequently employed to assess the redistribution of mining-induced stresses, and to compare the impact of different stope sequence scenarios on haulage network stability. In this study,typical geological settings in the Canadian shield were replicated in a numerical model with a steeplydipping tabular orebody striking EW. All other formations trended in the same direction except for two dykes on either side of the orebody with a WNW-EsE strike. Rock mass properties and in situ stress measurements from a case study mine were used to calibrate the model. Drifts and crosscuts were excavated in the footwall and two stope sequence scenarios-a diminishing pillar and a center-out one-were implemented in 24 mining stages. A combined volumetric-numerical analysis was conducted for two active levels by comparing the extent of unstable rock mass at each stage using shear,compressive, and tensile instability criteria. Comparisons were made between the orebody and the host rock, between the footwall and hanging wall, and between the two stope sequence scenarios. It was determined that in general, the center-out option provided a larger volume of instability with the shear criterion when compared to the diminishing pillar one(625,477 m~3 compared to 586,774 m~3 in the orebody; 588 m~3 compared to 403 m~3 in the host rock). However, the reverse was true for tensile(134,298 m~3 compared to 128,834 m~3 in the orebody; 91,347 m~3 compared to 67,655 m~3 in the host rock)instability where the diminishing pillar option had the more voluminous share.

关键词： Haulage drifts Rock mass instability Volumetric analysis stope sequences Numerical modeling

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Data-Fusion for Epidemiological Analysis of Covid-19 Variants in UAE

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Computers, Materials & Continua 2021年第9期68卷 3895-3913页

作者： Anoud Bani-hani Anaïs Lavorel Newel Bessadet Zayed University DubaiUnited Arab Emirates staffordshire University Stoke-on-TrentST42DEUnited Kingdom Keele University NewcastleST55BGUnited Kingdom

since December 2019,a new pandemic has appeared causing a considerable negative global *** sARs-CoV-2 first emerged from China and transformed to a global pandemic within a short *** virus was further observed to be spreading rapidly and mutating at a fast pace,with over 5,775 distinct variations of the virus observed globally(at the time of submitting this paper).Extensive research has been ongoing worldwide in order to get a better understanding of its behaviour,influence and more importantly,ways for reducing its *** analytics has been playing a pivotal role in this research to obtain valuable insights into understanding and fighting against the spread of ***,this is time and resource intensive,making it difficult to observe and quickly identify the impact of *** such as the spread or virulence could explain the three months delay in revealing the new virus variant in the *** paper presents an extensive correlation analysis of the effect caused by the different sARs-CoV-2 strains,and their influence on the population across diverse factors,such as propagation and fatality rates,during the peak of the pandemic,with a focus on two major countries in the Middle East,the United Arab Emirate(UAE)and the Kingdom of saudi Arabia(KsA).This research aims to investigate the epidemiological behaviour of the Coronavirus’genomic variants over time in the UAE,compared with the KsA,where correlation analysis is carried out for a number of cases,deaths and their statistical *** results of the analysis highlight very interesting insights into the epidemiological impact of the Covid-19 genomic behaviour in both countries,which could lead to important actions taken to minimize the impact on wider public health,possibly saving lives,and the *** instance,our method identifies a potential correlation between a spike in the number of deaths per case of 5.5 observed in the UAE by March 24th,with the emergence of new

关键词： sARs-CoV-2 genome covid-19 public health pandemic epidemiology case study United Arab Emirates UAE Kingdom of saudi Arabia KsA

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