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International Journal of Mining science and Technology 2013年第6期23卷 815-819页

作者： p.s.paul Department of Mining Engineering Indian School of Mines

Work injuries in mines are complex and generally characterized by several factors starting from personal to technical and technical to social *** this paper,investigation was made through the application of structural equation modeling to study the nature of relationships between the influencing/associating personal factors and work injury and their sequential relationships leading towards work injury occurrences in underground coal *** variables namely,rebelliousness,negative affectivity,job boredom,job dissatisfaction and work injury were considered in this *** were developed to quantify them through a questionnaire *** mine workers were randomly selected for the *** from 300 participants were used for the *** structural model of LIsREL was used to estimate the interrelationships amongst the *** case study results show that negative affectivity and job boredom induce more job dissatisfaction to the workers whereas risk taking attitude of the individual is positively influenced by job dissatisfaction as well as by rebelliousness characteristics of the ***,risk taking and job dissatisfaction are having positive significant direct relationship with work *** findings of this study clearly reveal that rebelliousness,negative affectivity and job boredom are the three key personal factors influencing work related injuries in mines that need to be addressed properly through effective safety programs.

关键词： structural equation modeling Mine safety Occupational health and safety Work injury

Rock mechanical investigation of strata loading characteristics to assess caving and requirement of support resistance in a mechanized powered support longwall face

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International Journal of Mining science and Technology 2016年第6期26卷 1081-1087页

作者： Aveek Mangal p.s.paul Department of Mining Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad826004JharkhandIndia

Longwall mining is one of the most acclaimed and widely used in underground method for coal extraction. The interaction of powered supports with the roof is the key issue in strata mechanics of longwall mining. Controlled caving of rock mass is a prerequisite pro thriving exploitation of coal deposits by longwall retreat with caving technique and support resistance has evolved as the most promising and effective scientific tool to predict various aspects related to strata mechanics of such workings. Load density,height of caving block, distance of fractured zone ahead of the face, overhang of goaf and mechanical strength of the debris above and below the support base have been found to influence the magnitude of load on supports. Designing powered support has been attempted at the different countries in different methods. This paper reviews the mechanism of roof caving and the conventional approaches of caving behaviour and support resistance requirement in the context of major strata control experiences gained worldwide. The theoretical explanation of the mechanism of roof caving is still continuing with consistently improved understanding through growing field experiences in the larger domain of geo-mining conditions and state-of-art strata mechanics analysis and monitoring techniques.

关键词：岩石力学综采支架顶板岩层载荷特性工作面地层控制评估地质采矿条件

The great catastrophe: causes of the permo-Triassic marine mass extinction

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National science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David p.G.Bond school of Earth & Environment University of Leeds school of Environmental sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in south China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(s) and the overwhelming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

prediction of Bandwidth of Metamaterial Antenna Using pearson Kernel-Based Techniques

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Computers, Materials & Continua 2024年第3期78卷 3449-3467页

作者： sherly Alphonse s.Abinaya sourabh paul school of Computer science and Engineering Vellore Institute of TechnologyChennai600127India school of Electronics Engineering Vellore Institute of TechnologyChennai600127India

The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial *** radiation cost and quality factor of the antenna are influenced by the size of the *** antennas allow for the circumvention of the bandwidth restriction for small *** parameters have recently been predicted using machine learning algorithms in existing *** learning can take the place of the manual process of experimenting to find the ideal simulated antenna *** accuracy of the prediction will be primarily dependent on the model that is *** this paper,a novel method for forecasting the bandwidth of the metamaterial antenna is proposed,based on using the pearson Kernel as a standard *** with these new approaches,this paper suggests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the pearson kernel to reduce the dimension.A novel algorithm for optimizing the parameters of Convolutional Neural Network(CNN)based on improved Bat Algorithm-based Optimization with pearson Mutation(BAO-pM)is also presented in this *** prediction results of the proposed work are better when compared to the existing models in the literature.

关键词： Antenna pearson optimization bandwidth metamaterial

Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： p.s.REDDY p.sREEDEVI Department of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEpCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing *** effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEpCMs,ranging from 2%to 6%,the stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented *** results indicate that the time taken by the NEpCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf ***,the contours of the heat capacity ratio Cr decrease with the increase in the stefan number ste.

关键词： volume fraction of nano-encapsulated phase change material(NEpCM) radiation stefan number heat capacity ratio entropy generation

Application of a simplified ADM1 for full-scale anaerobic co-digestion of cattle slurry and grass silage:assessment of input variability

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Frontiers of Environmental science & Engineering 2024年第4期18卷 125-139页

作者： sofia Tisocco sören Weinrich Gary Lyons Michael Wills Xinmin Zhan paul Crosson Civil Engineering College of Science and EngineeringUniversity of GalwayGalwayH91 TK33Ireland Teagasc Animal and Bioscience Research Department Animal and Grassland Research and Innovation CentreDunsanyC15 PW93Ireland Biochemical Conversion Department Deutsches Biomasseforschungszentrum gemeinnützige GmbHLeipzig 04347Germany Faculty of Energy·Building services·Environmental Engineering Münster University of Applied SciencesSteinfurt 48565Germany Agri-Food and Biosciences Institute HillsboroughBT266DRUK Ryan Institute University of GalwayGalwayH91 TK33Ireland MaREI Research Centre for Energy Climate and MarineRyan InstituteUniversity of GalwayGalwayH91 TK33Ireland

Mathematical modeling of anaerobic digestion is a powerful tool to predict gas yields and optimize the *** Anaerobic Digestion Model No.1(ADM1)is a widely implemented model for this ***,modeling full-scale biogas plants is challenging due to the extensive substrate and parameter characterization *** study describes the modification of the ADM1 through a simplification of individual process phases,characteristic components and required ***,the ability of the simplified model to simulate the co-digestion of grass silage and cattle slurry was evaluated using data from a full-scale biogas *** impacts of substrate composition(crude carbohydrate,protein and lipid concentration)and variability of carbohydrate degradability on simulation results were assessed to identify the most influential *** indicated that the simplified version was able to depict biogas and biomethane production with average model efficiencies,according to the Nash-sutcliffe efficiency(NsE)coefficient,of 0.70 and 0.67,respectively,and was comparable to the original ADM1(average model efficiencies of 0.71 and 0.63,respectively).The variability of crude carbohydrate,protein and lipid concentration did not significantly impact biogas and biomethane output for the data sets *** contrast,carbohydrate degradability seemed to explain much more of the variability in the biogas and methane ***,the application of simplified models provides a reliable basis for the process simulation and optimization of full-scale agricultural biogas plants.

关键词： ADM1 Agricultural feedstocks Biogas technology Input variability parameter estimation

猪血凝性脑脊髓炎病毒被动获得性抗体的持久性

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动物医学进展 1986年第2期 32-33页

作者： p.s.paul 赵景民

血凝性脑脊髓炎病毒(HEV)被动获得性抗体的持久性,是通过分别对10头母猪所产的4头仔猪测定的。母猪分娩时的初乳和血清样本(10头母猪的)有HEV的血凝抑制抗体。2日令的全部仔猪亦有HEV的血凝抑制抗体。仔猪的血循环中HEV的抗体大约4～18... 详细信息

血凝性脑脊髓炎病毒(HEV)被动获得性抗体的持久性,是通过分别对10头母猪所产的4头仔猪测定的。母猪分娩时的初乳和血清样本(10头母猪的)有HEV的血凝抑制抗体。2日令的全部仔猪亦有HEV的血凝抑制抗体。仔猪的血循环中HEV的抗体大约4～18周(平均10.5)呈非线性速度下降和存留。40头20周龄的仔猪血清反应全部阴性。 HEV是引起仔猪脑炎、呕吐、消瘦症的一种猪的日冕病毒。刚出生几周内的仔猪感染HEV发病最严重,成年猪较轻。对猪群血清学调查表明,尽管HEV感染率较高,但临床上自然发病的却较少。临床上仔猪对HEV病的易感性年令范围狭窄,在一次流行之后畜群迅速产生免疫应答,显示出在散发本病时,被动获得性抗体起到了保护仔猪免受HEV感染的作用。本研究是对仔猪临床上对HEV最易感的生命早期它们的血循环存在从初乳中获得的被动获得性抗体的水平及其抗体维持时间的测定。

关键词：仔猪血清血凝抑制抗体初乳获得性抗体血清样本母猪分娩 HEV 持久性

Hypoxic and temporal variation in the endocrine disrupting toxicity of perfluorobutanesulfonate in marine medaka(Oryzias melastigma)

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Journal of Environmental sciences 2024年第2期136卷 279-291页

作者： Baili sun Jing Li Yachen Bai Xiangzhen Zhou paul K.s.Lam Lianguo Chen state Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of sciences Beijing 100049China Office of the president Hong Kong Metropolitan University30 Good Shepherd StreetKowloonHong Kong SARChina

perfluorobutanesulfonate(pFBs)is an emerging pollutant capable of potently disrupting the sex and thyroid endocrine systems of ***,the hypoxic and temporal variation in pFBs endocrine disrupting toxicity remain largely *** the present study,adult marine medaka were exposed to environmentally realistic concentrations of pFBs(0 and 10μg/L)under normoxia or hypoxia conditions for 7 days,aiming to explore the interactive behavior between pFBs and *** addition,pFBs singular exposure was extended till 21days under normoxia to elucidate the time-course progression in pFBs *** results showed that hypoxia inhibited the growth and caused the suspension of egg spawn regardless of pFBs *** regard to the sex endocrine system,7-day pFBs exposure led to an acute stimulation of transcriptional profiles in females,which,subsequently,recovered after the 21-day *** potency of hypoxia to disturb the sex hormones was much stronger than pFBs.A remarkable increase in estradiol concentration was noted in medaka blood after hypoxia *** in sex endocrinology of coexposed fish were largely determined by hypoxia,which drove the formation of an estrogenic *** further enhanced the endocrine disrupting effects of ***,the hepatic synthesis of vitellogenin and choriogenin,two commonly used sensitive biomarkers of estrogenic activity,failed to initiate in response to the estrogen *** to sex endocrine system,disturbances in thyroidal axis by pFBs or hypoxia were relatively ***,the present findings will advance our toxicological understanding about pFBs pollutant under the interference of hypoxia.

关键词： perfluorobutanesulfonate(pFBs) Aquatic hypoxia Temporal toxicity Combined exposure Endocrine disruption Marine medaka

Diet and monensin influence the temporal dynamics of the rumen microbiome in stocker and finishing cattle

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Journal of Animal science and Biotechnology 2024年第2期15卷 733-748页

作者： Jianmin Chai Caleb p.Weiss paul A.Beck Wei Zhao Ying Li Jiangchao Zhao Guangdong provincial Key Laboratory of Animal Molecular Design and precise Breeding College of Life Science and EngineeringFoshan UniversityFoshanChina Division of Agriculture Department of Animal ScienceUniversity of ArkansasFayettevilleARUSA Department of Animal and Food sciences Oklahoma State UniversityStillwaterOKUSA Institute of Feed Research of Chinese Academy of Agricultural sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture and Rural AffairsBeijing 100193China

Background stocker cattle diet and management influence beef cattle performance during the finishing stage,but knowledge of the dynamics of the rumen microbiome associated with the host are lacking.A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen *** the stocker phase,either dry hay or wheat pasture were provided,and three levels of monensin were *** calves were then transported to a feedlot and received similar finishing diets with or without *** microbial samples were collected on d 0,28,85 during the stocker stage(s0,s28 and s85)and d 0,14,28,56,30 d before slaughter and the end of the trial during the finishing stage(F0,F14,F28,F56,pre-Ba,and Final).The V4 region of the bacterial 16s rRNA gene of 263 rumen samples was *** Higher alpha diversity,including the number of observed bacterial features and the shannon index,was observed in the stocker phase compared to the finishing *** bacterial amplicon sequence variants(AsVs)differentiating different sampling time points were *** treatments during the stocker stage temporally impact the dynamics of rumen *** example,shared bacteria,including Bacteroidales(AsV19)and streptococcus infantarius(AsV94),were significantly higher in hay rumen on s28,s85,and F0,while Bacteroidaceae(AsV11)and Limivicinus(AsV15)were more abundant in *** affected rumen microbial composition at a specific *** to feedlot significantly influenced microbiome structure and diversity in hay-fed *** taxa associated with body weight were classified,and core microbiotas interacted with each other during the *** In summary,the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding *** at the stocker phase may t

关键词： Beef cattle Diet Feedlot phase Monensin Next-generation sequencing Rumen microbiota stocker

Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri E Vijayatha V Ramasubramanian s Thiyagarajan p Department of science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates