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Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki biswas Nicola j.Wagner Ofentse M.Moroeng DSI-NRF CIMERA/PPM Research Group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the Madzaringwe Formation in Makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous b-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–GI),and groundwater–vegetation index(GWI–vi)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+Mn)and(Fe+Mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–Mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： Macerals Coal facies Geochemical-indices Hydrothermal Madzaringwe formation Soutpansberg Coalfield

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Full-spectrum bi@SrTiO_(3) for bi-directional promotion effects on photocatalytic redox reaction:Insight into intermediates and mechanism

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journal of Rare Earths 2024年第5期42卷 917-929,I0004页

作者： bin Liu Nanhao Zhou jun Liu Xinglei Wang Peter K.j.Robertson Xiaoyuan Chen Chao Chen jianmin Luo Chuanyi Wang School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan512005China Chengdu Customs Technology Center Chengdu610041China Key Laboratory of Pollutant Chemistry and Environmental Treatment College of Chemistry and Environmental ScienceYili Normal UniversityYining835000China School of Chemistry and Chemical Engineering Queen's University BelfastStranmillis RoadBelfastBT95AGUnited Kingdom Guangzhou Institute of Industrial Intelligence(GIII) Guangzhou511400China

The development of full-spectrum photocatalysts active in the near-infrared(NIR)region has gained increasing attention for deleterious pollutant *** integration of plasmonic metals with semico nductors is an effective way to widen the light re sponse range of photocatalysts due to the strong light absorption and fast plasmonic energy transfer of the localized surface plasmon resonance(LSPR).In this work,the full-spectrum responsive bi@SrTiO_(3) was prepared via facile solvothermal chemical *** optimal bi@SrTiO_(3) achieves exceptional photocatalytic Cr(vi)reduction efficiency and tetracycline degradation,realizing bi-directional promotion effects on redox *** to density functional theory(DFT)simulations,the extraordinary photocatalytic performance is attributed to the tunable builtin electric field(IEF)of the Ohmic *** favorable adaptability in real water and high stability of bSTO-25 were proved by experime ntal *** the po ssible photocatalytic mechanism was proposed based on theoretical calculation and experimental ***,the non-toxicity of the bSTO-25 was evaluated by *** cultivation,which further proves the feasibility of treating wastewater with *** work provides a new perspective on constructing full-spectrum-driven photocatalysts for applications dealing with environmental remediation.

关键词： Full-spectrum photocatalysts Localized surface plasmon resonance Ohmic contact Cr(Ⅵ)reduction Antibiotic degradation Rare earths

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Degradable magnesium-hydroxyapatite interpenetrating phase composites processed by current assisted metal infiltration in additive-manufactured porous preforms

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journal of Magnesium and Alloys 2022年第12期10卷 3641-3656页

作者： Mariano Casas-Luna Edgar b.Montufar Norbert Hort Sebastian Díaz-de-la-Torre joséClaudio Méndez-García Lucie vištejnová Adam brínek AlešDanhel Karel Dvorak jozef Kaiser Ladislav Celko Central European Institute of Technology Brno University of TechnologyPurkynova 123Brno 61200Czech Republic Institute of Metallic biomaterials Helmholtz-Zentrum HereonMax-Planck-Straße 1Geesthacht 21502Germany Institute of Product and Process Innovation Leuphana University LüneburgUniversitätsallee 1Lüneburg 21335Germany Centro de Investigación e Innovación Tecnológica Instituto Politécnico NacionalCerrada de Cecati s/nMexico City 02250Mexico biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 1655/76Plzen 32300Czech Republic Institute of biophysics of the Czech Academy of Sciences Královopolská135Brno 61265Czech Republic Faculty of Civil Engineering Brno University of TechnologyPurkynova 139Brno 61200Czech Republic

This work explores ceramic additive manufacturing in combination with liquid metal infiltration for the production of degradable interpenetrating phase magnesium/hydroxyapatite(Mg/HA) composites. Material extrusion additive manufacturing was used to produce stoichiometric,and calcium deficient HA preforms with a well-controlled open pore network, allowing the customization of the topological relationship of the composite. Pure Mg and two different Mg alloys were used to infiltrate the preforms by means of an advanced liquid infiltration method inspired by spark plasma sintering, using a novel die design to avoid the structural collapse of the preform. Complete infiltration was achieved in 8 min, including the time for the Mg melting. The short processing time enabled to restrict the decomposition of HA due to the reducing capacity of liquid Mg. The pure Mg-base composites showed compressive yield strength above pure Mg in cast state. Mg alloy-based composites did not show higher strength than the bare alloys due to grain coarsening, but showed similar mechanical properties than other Mg/HA composites that have significantly higher fraction of metallic phase. The composites showed faster degradation rate under simulated body conditions than the bare metallic component due to the formation of galvanic pairs at microstructural level. Mg dissolved preferentially over HA leaving behind a scaffold after a prolonged degradation period. In turn, the fast production of soluble degradation products caused cell metabolic changes after 24 h of culture with not-diluted material extracts. The topological optimization and reduction of the degradation rate are the topics for future research.

关键词： Interpenetrating phase composite biodegradable metal Topological relationship Direct ink writing Metal infiltration Computed aided design

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Formation process and oxidation behavior of MCrAlY+AlSiY composite coatings on a Ni-based superalloy

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journal of Materials Science & Technology 2022年第25期120卷 65-77页

作者： S.M.Li L.b.Fu W.L.Zhang W.Li j.Sun T.G.Wang S.M.jiang j.Gong C.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Advanced Research Institute for Multidisciplinary Science Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Tianjin Key Laboratory of High Speed Cutting and Precision Machining Tianjin University of Technology and EducationTianjin 300222China

An AlSiY coating and two MCrAlY+AlSiY composite coatings with different thickness of MCrAlY interlayer were prepared by arc ion plating(AIP)and vacuum *** isothermal oxidation behavior of coatings at 1100℃ for 300 h was also investigated to characterize the microstructure evolution of coatings during *** composite coatings exhibited a better high-temperature oxidation resistance at 1100℃ .The reason is that the addition of MCrAlY layer can greatly contribute to prevent the diffusion of refractory elements to the outer *** inhibition of Al inward diffusion can be much stronger,as the Si content increases in the outer layer during annealing.

关键词： Composite coating Annealing Arc ion plating SEM Oxidation

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Ion dynamics into different pore size distributions in supercapacitors under compression

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journal of Energy Chemistry 2023年第5期80卷 110-119,I0004页

作者： joão Pedro Aguiar dos Santos Cesar j.b.Pagan Rafael vicentini Reinaldo F.Teófilo Renato beraldo Leonardo M.Da Silva Hudson Zanin brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasAv.Albert Einstein 40CampinasSP13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil Multivariate Chemical Data Analysis Laboratory Department of ChemistryUniversidade Federal de Viçosa36570-900 ViçosaMGBrazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri's ValleyRodovia MGT 367km 5835000 Alto da Jacuba39100-000DiamantinaMGBrazil

Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic *** comprising the ion dynamics in SC electrodes under compression are still ***,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the *** excessive compression is applied,the accessible pore regions decrease,and the capacitance ***,as the studied hydrated ions have different dimensions,the match between ion/pore sizes *** the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 F g^(-1)and 30.9 to 39.0 F g^(-1),***,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7F g^(-1))achieved at 140 and 80 PSI,*** LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%.

关键词： Mechanic compression Pore size distribution lon dynamics Activated carbon Supercapacitors

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A practical model for efficient anti-fatigue design and selection of metallic materials:Ⅰ.Model building and fatigue strength prediction

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journal of Materials Science & Technology 2021年第11期70卷 233-249页

作者： R.Liu P.Zhang Z.j.Zhang b.Wang Z.F.Zhang Laboratory of Fatigue and Fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic *** this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been *** results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength *** this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue *** the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F *** the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and *** the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength ***,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield *** summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.

关键词： Yield strength Tensile strength Plasticity Fatigue strength Anti-fatigue design

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Study of the UHV ionization gauge and the residual gas analyzer sensitivities dependence on the residual gases inherency

Study of the UHV ionization gauge and the residual gas analy...

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第18届国际真空大会

作者： M. vi ar Z. Krají ek j. Tesa D. Prazák F. Staněk L. Peksa T. Gronych M. jeáb Czech Metrology Institute Charles University in Prague Faculty of Mathematics and Physics

The performed experiments with the residual gas analyzers show the dependence of the residual gas analyzer sensitivity for some gases on the background gases partial pressures. The kind of the influence of the background gases evinces that the ion current reduction may be caused by the loss of the cations between the ion source and the detector.

关键词： Ion source residual gas analyzer quadrupole mass spectrometer.

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Distribution of pericellular matrix molecules in the temporomandibular joint and their chondroprotective effects against inflammation

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International journal of Oral Science 2017年第1期9卷 43-52页

作者： Wern Cui Chu Shipin Zhang Timothy j Sng Yu jie Ong Wen-Li Tan vivien Y Ang Casper b Foldager Wei Seong Toh Faculty of Dentistry National University of SingaporeSingapore Orthopaedic Research Laboratory Aarhus University HospitalAarhusDenmark Tissue Engineering Program Life Sciences InstituteNational University of SingaporeSingapore

The objectives of this study were to （1） determine the distribution and synthesis of pericellular matrix （PCM） molecules （collagen vi, collagen IV and laminin） in rat temporomandibular joint （TMj） and （2） investigate the effects of PCM molecules on chondrocytes against inflammation in osteoarthritis. Four zones （fibrous, proliferating, mature and hypertrophic） of condylar cartilage and three bands （anterior, intermediate and posterior） of disc were analysed by immunohistochemistry for the presence of PCM molecules in rat TMjs. Isolated chondrocytes were pre-treated with PCM molecules before being subjected to interleukin （IL）-II~ treatment to stimulate inflammation. The responses of the chondrocytes were analysed using gene expression, nitric oxide release and matrix metalloproteinase （MMP）-13 production measures. Histomorphometric analyses revealed that the highest areal deposition of collagen vi （67.4%）, collagen IV （45.7%） and laminin （52.4%） was in the proliferating zone of TMj condylar cartilage. No significant difference in the distribution of PCM molecules was noted among the three bands of the TMj disc. All three PCM molecules were expressed intracellularly by chondrocytes cultured in the monolayer. Among the PCM molecules, pre-treatment with collagen vi enhanced cellular proliferation, ameliorated IL-lp-induced MMP-3, MMP-9, MMP-13 and inducible nitric oxide synthase gene expression, and attenuated the downregulation of cartilage matrix genes, including collagen I, aggrecan and cartilage oligomeric matrix protein （COMP）. Concurrently, collagen vi pretreatment inhibited nitric oxide and MMP-13 production. Our study demonstrates for the first time the distribution and role of PCM molecules, particularly collagen vi, in the protection of chondrocytes against inflammation.

关键词： cartilage chondrocytes collagen iV collagen W inflammation laminin pericellular matrix temporomandibular joint

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Suicide gene therapy of hepatocellular carcinoma and delivery procedure and route of therapeutic gene in vivo

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Hepatobiliary & Pancreatic Diseases International 2002年第3期1卷 373-377页

作者： Sun X.-Y. Wu Z.-D. Hu j.-b. Department of Surgery Tongji Hospital Tongji Med. Coll. Huazhong Univ. Sci Wuhan 430030 China

Objective: To study the induction of sensitivity toganciclovir (GCV) or acyclovir (ACV) in humanhepatocellular carcinoma (HCC) cell line trans-ferred by an Epstein-barr virus (EbV)-based repli-con expression vector carrying the herpes simplex vi-rus thymidine kinase (HSV-tk) gene, including kill-ing and "bystander" effect, and also the gene delive-ry procedure and route of gene therapy in vivo ***: Liposome-entrapped plasmid pDR2/tk wastransferred into HCC cells, and then different con-centrations of GCV or ACV were added. The trans-ferred cells were mixed with untransferred HCC cellsin different proportion and 200 μmol/L GCV wasthen added into each well. After 72 hours, all sam-ples were measured by MTT colorimetric assay. AnEbV-based plasmid eukarotic expression vector car-rying IL-2 cDNA was used. Three models of gene di-rect injection in the local liver, injection through theportal vein, and injection through the embolized he-patic artery were established in closed Wister *** each model, two subgroups, injected either na-ked plasmid DNA or lipofectin-plasmid complex wereincluded. The expression of the IL-2 gene was regu-larly examined ***: GCV or ACV could apparently kill thetransferred HCC cells at a concentration of 0. 2μmol/L. The inhibition rate was changed with dif-ferent drug concentrations. The "bystander" effectwas obviously induced at a transferred to untrans-ferred HCC cells ratio of 1:5. IL-2 gene expressionwas observed in liver cells of all animals on day 3,which reached peak within 3-7 days, and declined af-ter day 7. Injection of naked plasmid DNA throughthe hepatic artery plus embolization obtained a ***: EbV-based vector is suitable for carry-ing suicide gene therapy for hepatocellular carcino-ma. Gene direct delivery in vivo combined with in-terventional surgery can be used to treat hepatocellu-lar carcinoma.

关键词： hepatocellular carcinoma gene therapy gene transfer in vivo tk gene bystander effect Epstein-barr virus

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basin Geomorphology and Drainage Morphometry Parameters Used as Indicators for Groundwater Prospect: Insight from Geographical Information System(GIS) Technique

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journal of Earth Science 2014年第6期25卷 1018-1032页

作者： Kumar Avinash b Deepika K S jayappa National Centre for Antarctic & Ocean Research Department of Marine Geology Mangalore University

Influence of structural and lithological controls of various drainage patterns and their stream orientations（for 2nd, 3rd and 4th order steams） were identified to evaluate the direction and controlling factors of drainage network. To investigate the prospect of groundwater, hydrogeomorphological features of river basin viz. Mulki-Pavanje were identified and mapped. To evaluate the characteristics of the basin, different morphometric parameters（linear, areal and relief） were computed in sub-basin wise（Sb-I to-viI）. The linear parameters suggest drainage network is controlled by geomorphology. The form factor（Ff）, elongation ratio（Re） and circularity ratio（Rc） suggest that the basin is in an elongated shape. The drainage density（Dd） indicates resistant/permeable strata under medium-dense vegetation with moderate relief. The areal parameters of the sub-basins（except SbI and Ⅲ） indicates moderate ground-slopes associated with moderately permeable rocks, which promote moderate run-off and infiltration. Drainage texture（T） of the whole basin indicates coarse texture while the Sb-I, and Ⅲ showing an intermediate texture. The relief parameters namely ruggedness number（Rn） infers low basin relief and poor drainage density. To identify the most deficit/surplus zones of groundwater suitable weightages were assigned to the hydrogeomorphological units and morphometric parameters. The study reveal that the basin manifest that Sb-Ⅲ shall be most deficit zone of groundwater, whereas Sb-viI, vi and V are found to show increase in groundwater potentiality. Groundwater prospect area in this basin is estimated to be 7% area under poor, 44% area under moderate and 49% area under good to excellent. This paper demonstrated the potential application of geographical information system（GIS） techniques to evaluate the groundwater prospect in absence of traditional groundwater monitoring data.

关键词： hydrogeomorphology drainage morphometry prioritization groundwater prospect Mulki-Pavanje River basin remote sensing

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