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Timescales of interface-coupled dissolution-precipitation reactions oncarbonates

Geoscience Frontiers 2019年第1期10卷 17-27页

作者： Francois Renard Anja Royne Christine v.Putnis The Njord Centre Physics of Geological Processes Departments of Geoscience and Physics University of Oslo Univ. Grenoble Alpes Univ. Savoie Mont Blanc CNRS Institut für Mineralogie University of Münster The Institute for Geoscience Research (TIGeR) Department of Chemistry Curtin University

In the Earth's upper crust, where aqueous fluids can circulate freely, most mineral transformations are controlled by the coupling between the dissolution of a mineral that releases chemical species into the fluid and precipitation of new minerals that contain some of the released species in their crystal structure, the coupled process being driven by a reduction of the total free-energy of the system. Such coupled dissolution-precipitation processes occur at the fluid-mineral interface where the chemical gradients are highest and heterogeneous nucleation can be promoted, therefore controlling the growth kinetics of the new minerals. Time-lapse nanoscale imaging using Atomic Force Microscopy(AFM) can monitor the whole coupled process under in situ conditions and allow identifying the time scales involved and the controlling parameters. We have performed a series of experiments on carbonate minerals(calcite, siderite, dolomite and magnesite) where dissolution of the carbonate and precipitation of a new mineral was imaged and followed through time. In the presence of various species in the reacting fluid(e. g. antimony, selenium, arsenic, phosphate), the calcium released during calcite dissolution binds with these species to form new minerals that sequester these hazardous species in the form of a stable solid phase. For siderite, the coupling involves the release of Fe^(2+) ions that subsequently become oxidized and then precipitate in the form of FeIIIoxyhydroxides. For dolomite and magnesite,dissolution in the presence of pure water(undersaturated with any possible phase) results in the immediate precipitation of hydrated Mg-carbonate phases. In all these systems, dissolution and precipitation are coupled and occur directly in a boundary layer at the carbonate surface. Scaling arguments demonstrate that the thickness of this boundary layer is controlled by the rate of carbonate dissolution,the equilibrium concentration of the precipitates and the kinetics of diffus

关键词： Carbonates Atomic force microscopy Dissolution Precipitation Boundary layer Replacement

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The Trace Element Distribution Patterns of Ediacaran-Early Cambrian Black Shales and the origin of Selenium in the Guangning Area, Western Guangdong Province, South China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 1978-1991页

作者： TIAN Xinglei LUo Kunli Andrew v.ZUZA Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of the Chinese Academy of Sciences Nevada Bureau of Mines and Geology University of Nevada

The Ediacaran and early Cambrian black shales are widespread across the South China Craton （Yangtze and Cathaysia blocks）. However, the trace element distribution patterns of the Ediacaran and early Cambrian black shales in the Cathaysia Block are still unclear. In this study, thirty- four black shale samples in the Lechangxia Group （Ediacaran） and thirteen black shale samples in the lower Bacun Group （early Cambrian） from Guangning area, western Guangdong Province, South China, were analyzed for major and trace elements concentrations. Compared to the upper continental crust, the Ediacaran black shales exhibit strongly enriched Se, ga, and As with enrichment factor values （EF） higher than 10, significantly enrichedBi and Rb （10〉EF〉5）, weakly enriched Mo, Ba, Cs, v, In, Be, TI, and Th （5〉EF〉2）, normal U, Cr, Cd, Sc, Pb, Cu, and Li （2〉EF〉0.5）, and depleted Ni, Zn, Sr, and Co. Early Cambrian black shales display strongly enriched Se, ga, and As, significantly enriched Ba, Bi, and Rb, weakly enriched Mo, Cs, Cd, v, U, Be, In, and TI, normal Sc, Th, Cr, Li, Cu, Ni, and Pb and depleted Co, Zn, and Sr. Moreover, Se is the most enriched trace element in the Ediacaran and early Cambrian black shales： concentrations vary from 0.25 to 30.09 ppm and 0.54 to 5.01 ppm, and averaging 4.84 and 1.72 ppm, with average EF values of 96.87 and 34.32, for the Ediacaran and early Cambrian shales respectively. The average concentration of Se in the Ediacaran black shales is 2.8 times higher than that of early Cambrian black shales. Se contents in the Ediacaran and early Cambrian black shales exhibit significant variation （P = 0.03）. Provenance analysis showed that Se contents of both the Ediacaran and early Cambrian black shales were without detrital provenance and volcanoclastic sources, hut of hydrothermal origin. The deep sources of Se and the presence of pyrite may explain the higher Se contents in the Ediacaran black shales. Similar with the Se-rich characteristics of the contemporan

关键词： black shale selenium Ediacaran and early Cambrian Guangning area Cathaysia block

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Crustal stabilization:Evidence from the geochemistry and U–Pb detrital zircon geochronology of quartzites from Simlipal Complex,Singhbhum Craton,India

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Geoscience Frontiers 2022年第1期13卷 46-61页

作者： C.S.Sindhuja Arijit Pahari C.Manikyamba M.Santosh Li Tang Jyotisankar Ray K.S.v.Subramanyam Madhuparna Paul I.Gonzalez-Alvarez P.C.Sruthi CSIR(Council of Scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India School of Earth Science and Resources China University of GeosciencesBeijing 100083China Department of Geology University of CalcuttaKolkataIndia CSIRo Mineral ResourcesWestern AustraliaAustralia

Cratonic stabilization was a critical crustal process during the Hadean to Archean for the formation of *** understanding of how and where this process took place is significant to evaluate the architecture of *** Singhbhum Craton of eastern India has well preserved Precambrian volcanosedimentary *** Simlipal volcano-sedimentary complex of Singhbhum Craton consists of circular bands of mafic volcanic rocks interlayered with quartzites/shales/*** the present study,we report petrographic and geochemical characteristics of quartzites from Simlipal Complex coupled with U–Pb ages of detrital zircons and zircon geochemistry to understand the provenance and depositional conditions and its connection with the crustal stabilization in the Singhbhum *** quartzites are texturally mature with sub-angular to sub-rounded quartz grains followed by feldspars embedded in a silty *** on modal compositions and major element ratios,these quartzites are categorized as quartz arenite and sub-lithic *** element abundances normalized to Archean Upper Continental Crust(AUCC)display positive anomalies at U,Zr,Hf and negative anomalies at *** patterns are characterized by negative Eu anomalies(Eu/Eu^(*)=0.47–0.97)and flat HREE suggesting felsic *** quartzites show depletion of LILE,enrichment of HFSE and transition metals relative to *** weathering indices such as CIA,PIA,and ICv are suggestive of moderate to intense chemical *** trace element ratios such as Th/Cr,Th/Sc,La/Sc,La/Co and Th/Co indicate a predominantly felsic source for these *** overall geochemical signatures indicate passive margin deposition for these *** zircons from the Simlipal quartzites yield U–Pb ages 3156±31 Ma suggesting Mesoarchean crustal *** trace element geochemistry of detrital zircons suggests that the zircons are magmatic in origin and possibly derived from the 3.1 ga anorogenic grani

关键词： Quartzites Simlipal Complex Singhbhum Craton U-Pb geochronology Crustal stablilization

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Instability and sensitivity analysis of flows using openFoAM~

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Chinese Journal of Aeronautics 2016年第2期29卷 316-325页

作者： Liu Qiong F. Gomez J.M. Perez v. Theofilis School of Aeronautics Universidad PolitOcnica de Madrid Plaza Cardinal Cisneros 3 Madrid E-28040 Spain Department of Mechanical and Aerospace Engineering Monash University Victoria 3800 Australia

The present contributions deal with the development and implementation of the direct and adjoint incompressible Navie-Stokes equations in a matrix-free time-stepping context making use of the open-source openFoAM~ （open source field operation and manipulation） C ＋＋ tool- box. It is shown that a few minor modifications in the source code can enable these multi-purpose computational fluid dynamics （CFD） solvers to carry out global instability analysis of three- dimensional flows of engineering interest, exploiting all additional capabilities of such codes. The strength of this methodology is demonstrated through the analysis of an interesting selection of ooen and wall-bounded flows.

关键词： Adjoint-based analysis Computational fluid dynam-ics Flow instability openFoAM Time-stepping method

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Frontiers of physics 2016年第5期11卷 57-78页

作者： v. R. Shaginyan A. Z. Msezane G. S. Japaridze K. G. Popov v. A. Khodel Petersburg Nuclear Physics Institute NRC Kurchatov Institute Gatchina 188300 Russia Clark Atlanta University Atlanta GA 30314 USA Komi Science Center Ural Division RAS Syktyvkar 167982 Russia Russian Research Centre Kurchatov Institute Moscow 123182 Russia McDonnell Center for the Space Sciences & Department of Physics Washington University St. Louisa MO 63130 USA

The aim of this review paper is to expose a new state of matter exhibited by strongly correlated Fermi systems represented by various heavy-fermion （HF） metals, two-dimensional liquids like 3He, compounds with quantum spin liquids, quasicrystals, and systems with one-dimensional quantum spin liquid. We name these various systems HF compounds, since they exhibit the behavior typical of HF metals. In HF compounds at zero temperature the unique phase transition, dubbed throughout as the fermion condensation quantum phase transition （FCQPT） can occur; this FCQPT creates flat bands which in turn lead to the specific state, known as the fermion condensate. Unlimited increase of the effective mass of quasiparticles signifies FCQPT; these quasiparticles determine the thermodynamic, transport and relaxation properties of HF compounds. our discussion of numerous salient experimen- tal data within the framework of FCQPT resolves the mystery of the new state of matter. Thus, FCQPT and the fermion condensation can be considered as the universal reason for the non-Fermi liquid behavior observed in various HF compounds. We show analytically and using arguments based completely on the experimental grounds that these systems exhibit universal scaling behavior of their thermodynamic, transport and relaxation properties. Therefore, the quantum physics of different HF compounds is universal, and emerges regardless of the microscopic structure of the compounds. This uniform behavior allows us to view it as the main characteristic of a new state of matter exhibited by HF compounds.

关键词： quantum phase transition flat bands systems quantum spin liquids heavy fermions effects scaling behavior new state of matter non-Fermi-liquid states strongly correlated electron quasicrystals thermoelectric and thermomagnetic

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Cyclic Stability of Superelasticity in[001]‑oriented Quenched Ni_(44)Fe_(19)ga_(27)Co_(10)and Ni_(39)Fe_(19)ga_(27)Co_(15)Single Crystals

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 650-660页

作者： E.E.Timofeeva E.Yu.Panchenko A.S.Eftifeeva A.I.Tagiltsev N.Yu.Surikov A.B.Tokhmetova E.I.Yanushonite M.v.Zherdeva I.Karaman Yu.I.Chumlyakov Tomsk State University Novosobornaya Square 1Tomsk 634050Russia Texas A&M University College StationTX 77843USA

The study of the influence of the cobalt content on the cyclic stability of superelasticity(SE)was carried out in quenched Ni_(44)Fe_(19)ga_(27)Co_(10)and Ni_(39)Fe_(19)ga_(27)Co_(15)(at.%)single crystals under *** is shown that an increase in the cobalt content leads to embrittlement of the material and a decrease in the cyclic stability of *** Ni_(44)Fe_(19)ga_(27)Co_(10)single crystals,during the first 20 loading/unloading cycles,the elastic energy relaxation occurs along with the formation of dislocations and residual martensite,which leads to a decrease in critical stress of martensite formation and in stress *** the next 80 cycles,SE becomes more *** is accompanied by a slight change in the *** the contrary,Ni_(39)Fe_(19)ga_(27)Co_(15)single crystals are characterized by high-strength characteristics,which lead to high SE stability during the first 20 loading/unloading ***,after 20 cycles,a strong degradation of the SE is observed through the formation of microcracks,which ultimately leads to the destruction of the *** results of work are replicable for cycling at different temperatures from all temperature ranges of superelasticity.

关键词： Martensitic transformations Superelasticity Single crystals Cyclic stability Microstructure

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Universal Deformation Rings of Modules over Self-injective Cluster-Tilted Algebras Are Trivial

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Algebra Colloquium 2021年第2期28卷 269-280页

作者： I.D.M.gaviria JoséA.vélez-Marulanda Peng Shan Universidad Nacional de Colombia Bogota D.C.Colombia Department of Mathematics Valdosta State UniversityValdostaGAUSA 不详

Let k be a fixed algebraically closed field of arbitrary characteristic,let Λ be a finite dimensional self-injective k-algebra,and let ∨ be an indecomposable non-projective left Λ-module with finite dimension over *** prove that if τΛ∨ is the Auslander-Reiten translation of ∨,then the versal deformation rings R(Λ,∨)and R(Λ,τΛ∨)(in the sense of *** and the second author)are *** use this to prove that if Λ is further a cluster-tilted k-algebra,then R(Λ,∨)is universal and isomorphic to k.

关键词： self-injective cluster tilted algebras Frobenius algebras (uni)versal deformation rings

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Decreased plasma urotensin Ⅱ levels inversely correlate with extent and severity of coronary artery disease

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Journal of Geriatric Cardiology 2007年第2期4卷 105-110页

作者： v. Borlo.gan Christine E. Stahl Department of Neurology Medical College of Georgia Augusta GA 30912 USA Department of Internal Medicine Dwight D. Eisenhower Army Medical Center Fort Gordon GA 30909 USA

objective To determine the plasma urolensin Ⅱ(UII) levels in various types of coronary heart disease and to clarify how the plasma UII levels correlate with the clinical presentation, extent and severity of coronary artery atherosclerosis (CAD). Methods: one hundred and three aged patients undergoing elective diagnostic coronary angiography for proven or clinical suspected coronary heart disease were enrolled in this study. The extent and severity of coronary artery disease were evaluated by vessel score and Gensini score, respectively. Plasma UII levels were measured by radioimmunoassay. Results: The plasma UII levels in the patients with modest to severe coronary stenosis (3.03±0.34 pg/ml, 1.83±0.67 pg/ml) were significantly lower than that in subjects with normal coronary artery (4.80±1.11 pg/ml, Pvels in patients with coronary heart disease were also significantly lower than that in patients with insignificant coronary stenosis (P ompared to patients with stable angina pectoris, plasma UII levels in patients with acute coronary syndrome were significantly decreased (1.89±0.51 pg/ml vs 2.42±0.77 pg/ml, P vels were found to be negatively correlated with the severity of coronary artery stenosis (r = -0.488, Pvessel score (r = -0.408, Ponclusion: Significant inverse correlations exist between the plasma UII levels, and the extent and severity of coronary artery stenosis. These findings suggest that plasma UII contribute to the development and progression of coronary artery stenosis, and may be a novel marker to predict clinical types, as well as the extent and severity of coronary artery disease in the patients.

关键词： Urotensin Ⅱ Coronary artery atherosclerosis Coronary heart disease

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Simulation of clinker grinding circuits of cement plant based on process models calibrated using ga search method

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Journal of Central South University 2014年第2期21卷 799-810页

作者： A.Farzanegan E.Ghasemi Ardi A.valian v.Hasanzadeh School of Mining College of EngineeringUniversity of Tehran Department of Mining Faculty of EngineeringUniversity of Kashan

Particle size distributions of obtained samples from several sampling campaigns were determined and raw data were mass balanced before being used in simulation *** determination of breakage function,selection function,Bond work index,residence time distribution parameters,and Whiten's model parameters for air separators and diaphragms between the two compartments of tube ball mills,performance of the circuits was simulated for given throughputs and feed particle size ***'s model parameters were determined by ga(genetic algorithm) toolbox of MATLAB *** on implemented models for modeling and simulation,optimization of circuits was carried *** increased nearly 10.5% and 15.8% in fresh feed capacity input to each tube ball *** addition,circulating load ratios of circuits are modified to 118% and 127% from low level of 57% and 22%,respectively,and also cut points of air separators are adjusted at 30 and 40 μm from high range of 53 and 97 μm,*** applications helped in well-operation and energy consumption reduction of equipments.

关键词：遗传算法过程模型水泥厂搜索方法磨矿回路模拟 MATLAB软件空气分离器

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Blood Count Characteristics of Children Hospitalized in General Pediatrics at the gabriel Touré Teaching Hospital

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open Journal of Pediatrics 2023年第4期13卷 543-552页

作者： Pierre Togo Abdoul Karim Doumbia oumar Coulibaly Abdoul Aziz Diakité Moussa Tembély Adama Dembélé Hawa Gouro Diall Mohamed Elmouloud Cissé Fousseyni Traoré Belco Maïga Karamoko Sacko Djénéba Konaté Ibrahim Ahamadou Fatoumata Léonie Diakité Lala N’Drainy Sidibé Guédiouma Dembélé oumou Koné Amadou Touré Yacouba Aba Coulibaly Leyla Bagna Maïga Aminata Doumbia Hawa Konaré Kalirou Traoré Souleymane Sagara Tati Simaga Fatoumata Dicko Mariam Sylla Boubacar Togo Department of Pediatrics Gabriel Touré Teaching Hospital Bamako Mali National Institute for Health Science Training Bamako Mali Pediatrics Department Mohamed V Perinatal Clinic Bamako Mali Pediatrics Department DSSA Bamako Mali National Institute of Public Health “NIPH” Bamako Mali

objective: The main objective was to study the disturbances of the Blood Count of children hospitalized in the general pediatric of the gabriel Touré teaching hospital. Methods: This was a prospective and descriptive study conducted from September 1 to November 30, 2018 in the general pediatrics department of the gabriel Touré teaching hospital in Bamako. Data were collected on patient records using a survey sheet. Results: We collected 512 files of children out of 1030 admissions during the study period;the rate of completion of the blood count is 50%. The male sex was predominant with a sex ratio of 1.3. The majority of patients were under 5 years old (58%). The majority of fathers (56%) and mothers (64%) of children had no education;they are mainly farmers (61%) and housewives (88%). Pallor was the reason for consultation in 29% of patients and present in 60%. on blood count, anemia was present in 92% of patients, half of whom (50%) had severe anemia with a hemoglobin level below 7 g/dL. The anemia was mainly microcytic (72%) and hypochromic (66%). Hyperleukocytosis (62%), eosinophilia (68%) and basophilia (58%) were the abnormalities observed in the white line. Thrombocytopenia accounted for 40%. Severe malaria (53%) was the main discharge diagnosis and almost all patients (99%) were alive at discharge. Conclusion: The characteristics of anemia require a study of the complete blood count in healthy children with dosage of serum iron and ferritin for a better understanding of the phenomenon.

关键词： Characteristic Blood Count Child

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