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Investigation of the transformation of organic matter of carbonate deposits of the Semiluksky-mendymsky horizon under hydrothermal conditions

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Petroleum 2024年第2期10卷 216-223页

作者： S.m.Petrov A.I.Lakhova E.g.moiseeva A.g.Safiulina Institute of Petroleum Chemistry and NanotechnologiesKazan National Research Technological UniversityKazan420015Russia Institute of geology and Oil and gas Technologies Kazan Federal UniversityKazan420008Russia

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the Semiluksko-mendymsky horizon of the Romashkino oil field in a hydrothermal fluid for an hour(with a water-to-rock ratio of 33)at 340℃and 380℃and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃and 17 mPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the SARA analysis,the content of asphaltenes increases and the content of resins,aromatic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃and 20 mPa increases the degree of kerogen conversion from 12.4%to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃and 17 mPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C_(11)-C_(17),C_(19)-C_(22)alkyltrimethylbenzenes *** to IR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aromatic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aromaticity and the content of conde

关键词： Carbonate deposits Organic matter Hydrothermal fluid mobile hydrocarbons

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Automatic Rule discovery for data Transformation Using Fusion of diversified Feature Formats

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Computers, materials & Continua 2024年第7期80卷 695-713页

作者： g.Sunil Santhosh Kumar m.Rudra Kumar department of CSE Jawaharlal Nehru Technological UniversityAnantapur515002India department of CSE Marri Laxman Reddy Institute of Technology and ManagementHyderabad500043India department of Information Technology Mahatma Gandhi Institute of TechnologyHyderabad500075India

This article presents an innovative approach to automatic rule discovery for data transformation tasks leveraging XgBoost,a machine learning algorithm renowned for its efficiency and *** framework proposed herein utilizes the fusion of diversified feature formats,specifically,metadata,textual,and pattern *** goal is to enhance the system’s ability to discern and generalize transformation rules fromsource to destination formats in varied ***,the article delves into the methodology for extracting these distinct features from raw data and the pre-processing steps undertaken to prepare the data for the *** sections expound on the mechanism of feature optimization using Recursive Feature Elimination(RFE)with linear regression,aiming to retain the most contributive features and eliminate redundant or less significant *** core of the research revolves around the deployment of the XgBoostmodel for training,using the prepared and optimized feature *** article presents a detailed overview of the mathematical model and algorithmic steps behind this ***,the process of rule discovery(prediction phase)by the trained XgBoost model is explained,underscoring its role in real-time,automated data *** employingmachine learning and particularly,the XgBoost model in the context of Business Rule Engine(BRE)data transformation,the article underscores a paradigm shift towardsmore scalable,efficient,and less human-dependent data transformation *** research opens doors for further exploration into automated rule discovery systems and their applications in various sectors.

关键词： XgBoost business rule engine machine learning categorical query language humanitarian computing environment

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Influence of curing conditions on the shrinkage behavior of three-dimensional printed concrete formwork

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1225-1236页

作者： m.BEKAERT K.van TITTELBOOm g.de SCHUTTER magnel-Vandepitte Laboratory for structural Engineering and Building materials Department of Structural Engineering and Building MaterialsFaculty of Engineering and ArchitectureGhent UniversityGhent 60 B-9052Belgium

The use of three-dimensional(3d)printed concrete as formwork is becoming more widely applied within the ***,the technology is still not optimized and there are many reports of preliminary cracking during the curing of cast *** is believed to result from differential shrinkage between the printed and cast *** cracks(in the printed concrete or at the interface between the infill and printed concrete)form a preferential path for aggressive substances and can reduce the durability of the combined concrete *** ensure the desired service life of the structure,it is important that the differential shrinkage between cast and printed concrete is *** study investigated the effect of curing conditions on the differential shrinkage behavior of 3d and cast *** influence of prewetting of the dry-cured 3d printed formwork was also *** the experimental program,a vibrated and self-compacting concrete were used as cast *** 3d printed formwork was produced and combined with cast concrete to simulate a concrete *** formwork was cured for 1,7,or 28 d exposed to the air(relative humidity:60%or 95%)or submerged in *** length change of the combined elements was observed over 56 d after concrete casting and throughout the thickness of the *** show that increasing the curing period in dry conditions of the printed concrete leads to an expansion of the formwork on the first day after *** expansion leads to a non-uniform strain evolution throughout the curing period of the combined *** concrete formwork stored in wet conditions does not expand after the casting process but tends to show a decreasing linear deformation within the whole elements.

关键词： 3d concrete printing formwork shrinkage curing

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Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.g.PAVITHRA B.J.gIREESHA m.L.KEERTHI department of Pg Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India department of mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(AdSTm) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(AdSTm) trihybrid nanofluid magnetic field

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Pressurized environments directly influence friction and wear of dry steel contacts—Investigations in a novel high fluid pressure tribometer

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Friction 2024年第7期12卷 1599-1617页

作者： Paul REICHLE Jakob BARZ georg UmLAUF günter E.m.TOVAR Institute of Interfacial Process Engineering and Plasma Technology(IgVP) University of StuttgartStuttgart 70569Germany Fraunhofer Institute for Interfacial Engineering and Biotechnology(IgB) Stuttgart 70569Germany

To reduce the usage of classical lubricants in deep drawing,a new tribological system based on volatile lubricants was ***,a volatile medium is injected under high pressure into the interstice between drawing tool and sheet *** on temperature and pressure,the temporary lubricant may exist in its gaseous or liquid *** this study,a novel high fluid pressure tribometer was designed to investigate the friction and wear of dry steel contacts under comparable conditions like in dry deep ***,a new ball-on-disc tribometer was designed and integrated into a high-pressure *** specifically investigate the effects of different environments(technical air,liquid and gaseous carbon dioxide,nitrogen,argon)at atmospheric and high pressure(0.1 mPa,6 mPa)on tribology,the specimens and all components were operating *** the experiments,the friction was measured *** show that the highest friction occurs in air and the lowest in carbon dioxide *** to the experiments,the wear of the specimens was assessed along with changes in surface chemistry related to tribochemical ***,the tribology of the dry sliding contacts is correlated to changes of the surface *** differences as well as similarities regarding the different fluid environments are *** the results show,the differences between the media used are most pronounced at elevated ***,this work gives clear indications on the suitability of volatile lubricants in dry friction or rather gas lubrication,especially for dry deep drawing.

关键词： dry friction and dry wear gas lubrication carbon dioxide tribo-layer dry metal forming

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Predictor-corrector Fdm analysis of mHd darcy-Forchheimer flow of a micropolar fluid with viscous dissipation and heterogeneoushomogeneous

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Propulsion and Power Research 2024年第2期13卷 257-272页

作者： d.Thenmozhi m.Eswara Rao department of mathematics Saveetha School of EngineeringSIMATSChennaiTamilnaduIndia

This research delves into an intricate exploration ofﬂuid dynamics within heat transfer systems,with a speciﬁc focus on enhancing our understanding and improving system efﬁ*** a sophisticated mathematical model,the study incorporates micropolarﬂuid dynamics,micro rotational effects,laminarﬂow characterized by the darcy-Forchheimer model,inertia effects,and chemical reactions within a heat transfer system featuring boundary layer *** mathematical framework consists of partial differential equations(PdEs),and the study utilizes advanced numerical techniques,including the(PC4-Fdm)Predictor-Corrector Finite difference method and the shooting method,to solve these govern-ing *** inclusion of quantized mesh points and analysis of convergence using 4th orderﬁnite difference methods enhances the precision of the obtained *** param-eters are scrutinized to draw meaningful *** heterogeneous parameter reveals an increasing trend inﬂuid concentration,while the homogeneous parameter indicates a collision effect leading to a decrease inﬂuid *** Eckert number,associated with viscous dissipation,exhibits a correlation with decreasedﬂuid temperature and increasedﬂuid *** rotation parameters suggest a parallel increase inﬂuid velocity and a marginal decrease inﬂuid ***,the darcy-Forchheimer parameter,reﬂective of inertial effects,showcases an increase inﬂuid temperature and decrease in velocity in the convection *** the industrial implications,the study underscores the signiﬁcance of convection heat transfer systems in the context of ***ﬁndings offer valuable insights for optimizing heating and cooling processes in diverse industrial applications,ranging from power plants to waste heat recovery units and pharmaceutical industries.ª2024 The *** services by Elsevier *** behalf of KeAi Communications ***.

关键词： Predictor-corrector micropolarﬂuid magnetohydrodynamics(mHd) Viscous dissipation Homogeneous-heterogeneous

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Periodontitis:An often-neglected complication of diabetes

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World Journal of diabetes 2024年第3期15卷 318-325页

作者： marina g Kudiyirickal Joseph m Pappachan Primary Care dental Practice The Smile ClinicPreston PR16PZUnited Kingdom department of Endocrinology and metabolism Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Faculty of Science Manchester Metropolitan UniversityManchester M156BHUnited Kingdom Faculty of Biology Medicine and HealthThe University of ManchesterManchester M139PLUnited Kingdom

The bidirectional association between type 2 diabetes mellitus(T2dm)and periodontitis is now well established,resulting in periodontal disease being considered as the 6th major complication of diabetes mellitus(dm)after cardiovascular disease,eye disease,neuropathy,nephropathy,and peripheral vascular *** can worsen the virulence and invasiveness of pathogenic oral microbial flora aggravating the local inflammation and infection in those with periodontal *** the other hand,the chemical and immunological mediators released into the circulation as part of periodontal inflammation worsen the systemic insulin resistance with worsening of *** if undiagnosed or left untreated can also result in eventual tooth loss.A study by Xu et al in the World Journal of diabetes examined the predictive factors associated with periodontitis in Chinese patients with *** prevalence of periodontitis was found to be 75.7%in this *** on logistic regression analysis,the predictive factors for higher risk were low tooth brushing frequency[odds ratio(OR)=4.3],high triglycerides(Tg;OR=3.31),high total cholesterol(TC;OR=2.87),higher glycated hemoglobin(HbA1c;OR=2.55),and higher age(OR=1.05)while higher education level was protective(OR=0.53).However,the most influential variables were HbA1c followed by age,TC,Tg,low education level,brushing frequency,and sex on the random forest model(this model showed higher sensitivity for predicting the risk).A good understanding of the predictors for periodontitis in T2dm patients is important in prevention,early detection of susceptible patients,and intervention to improve periodontal health and enable long-term glycaemic control as observed by Xu et al.

关键词： diabetes mellitus Periodontitis Predictive factors Cardiovascular disease glycaemic control

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The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa W.R.dunn A.Foster F.S.Porter d.g.Sibeck B.Walsh The Henry A.Rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATmOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SmILE’s(Solar wind magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission mapper(LEm),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEm will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SmILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

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Optical measurements of dissolved organic matter as proxies for COd_(mn)and BOd_(5)in plateau lakes

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Environmental Science and Ecotechnology 2024年第3期19卷 132-138页

作者： Xuan Yang Yongqiang Zhou Xiaoying Yang Yunlin Zhang Robert g.m.Spencer Justin d.Brookes Erik Jeppesen Hucai Zhang Qichao Zhou Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesYunnan UniversityKunming650500China Institute of International River and Eco-security Yunnan UniversityKunming650500China Zhejiang College of Security Technology Wenzhou325016China Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and EnvironmentNanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing210008China department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee32306United States Water Research Centre School of Biological ScienceThe University of AdelaideAdelaide5005Australia department of Ecoscience Aarhus UniversityAarhus8000Denmark Sino-danish Centre for Education and Research Chinese Academy of SciencesBeijing100101China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and ImplementationMiddle East Technical UniversityAnkara06800Turkey Institute of marine Sciences Middle East Technical UniversityErdemliMersin33731Turkey Yunnan Key Laboratory of Pollution Process and management of Plateau Lake-Watershed Yunnan Research Academy of Eco-environmental SciencesKunming650034China

The presence of organic matter in lakes profoundly impacts drinking water supplies,yet treatment processes involving coagulants and disinfectants can yield carcinogenic disinfection *** assessments of organic matter,such as chemical oxygen demand(COd_(mn))and biochemical oxygen demand(BOd_(5)),are often ***,optical measurements of dissolved organic matter(dOm)offer a rapid and reliable means of obtaining organic matter composition *** we employed dOm optical measurements in conjunction with parallel factor analysis to scrutinize COd_(mn)and BOd_(5)*** was performed using an independent dataset encompassing six lakes on the Yungui Plateau from 2014 to 2016(n=256).Leveraging multiple linear regressions(mLRs)applied to dOm absorbance at 254 nm(a254)and fluorescence components C1-C5,we successfully traced COd_(mn)and BOd_(5)variations across the entire plateau(68 lakes,n=271,R^(2)>0.8,PdOm optical indices yielded superior estimates(higher R^(2))of COd_(mn)and BOd_(5)during the rainy season compared to the dry season and demonstrated increased accuracy(R^(2)>0.9)in mesotrophic lakes compared to oligotrophic and eutrophic *** study underscores the utility of mLR-based dOm indices for inferring COd_(mn)and BOd_(5)variability in plateau lakes and highlights the potential of integrating in situ and remote sensing platforms for water pollution early warning.

关键词： dissolved organic matter Chemical oxygen demand Biochemical oxygen demand Water quality Yungui plateau lakes

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Tensile deformation of fine-grained mg at 4K,78K and 298K

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Journal of magnesium and Alloys 2024年第6期12卷 2534-2556页

作者： m.Walag A.Kula P.Noga T.Tokarski g.Cios m.Niewczas AgH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AgH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland materials Science and Engineering McMaster UniversityHamiltonCanada

The impact of grain size, ranging from 0.9 μm to 9 μm, on the mechanical properties of commercially pure mg is investigated at temperatures of 4K, 78K, and 298K. The mechanisms governing plastic flow are influenced by both grain size and temperature. At 4K and 78K, dominant deformation modes in mg involve dislocation glide and extension twinning, regardless of grain size. The interactions between basal and non-basal dislocations and dislocations with grain boundaries promote an unusually high rate of work hardening in the plastic regime, leading to premature failure. The yield stress follows the Hall-Petch relationship σy~ k/√d, with the slope k increasing with decreasing temperature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(gBS) becomes significant in samples with grain sizes below 3 μm, considerably enhancing the material's deformability. gBS activation provides an additional recovery mechanism for dislocations accumulating at grain boundaries, facilitating their absorption during sliding and rotation. Analysis of σ Θ relationship suggests that the basal slip is the dominant dislocation mode in mg at 298K. decreasing grain size suppresses dislocation activity and twinning and increases gBS, resulting in lower Θ and σ Θ values. Suppressing conventional deformation modes coupled with enhanced gBS yields stress softening, breaking down the Hall-Petch relationship in mg below 3 μm grain size, leading to an inverse Hall-Petch behaviour. The work reports new data on the strength, ductility, work hardening and fracture behaviour, and their variations with mg grain size across different temperature regimes.

关键词： Polycrystalline mg mechanical properties deformation mechanisms Work-hardening Texture evolution Cryogenic temperatures Hall-Petch relationship

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