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Geochemistry of Platinum Group and Rare Earth Elements of the Polymetallic Layer in the Lower Cambrian,Weng'an,Guizhou Province

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 618-627页

作者： FU Yong wu Chaodong guan ping QU Wenjun CHEN Jiafu Key Laboratory of Orogenic Belts and Crustal Evolution MOE Peking University Beijing 100871 China National Research Center of Geoanalysis Beijing 100037 China

The black shales of the Lower Cambrian Niutitang Formation in Weng＇an, on the Yangtze platform of south China, contain voluminous polymetallic sulfide deposits. A comprehensive geochemical investigation of trace, rare earth, and platinum group elements （PGE） has been undertaken in order to discuss its ore genesis and correlation with the tectono-depositional setting. The ore-bearing layers enrich molybdenum （Mo）, nickel （Ni）, vanadium （V）, lead （Pb）, strontium （Sr）, barium （Ba）, uranium （U）, arsenic （As）, and rare earth elements （REE） in abundance. High uranium/ thorium （U/Th） ratios （U/Th〉I） indicated that mineralization was mainly influenced by the hydrothermal process. The 8U value was above 1.9, showing a reducing sedimentary condition. The REE patterns showed high enrichment in light rare earth elements （LREE）（heavy rare earth elements （HREE）（LREE/HREE=5-17）, slightly negative europium （Eu） and cerium （Ce） anomalies （δEu=0.81- 0.93）, and positive Ce anomalies （δCe=0.76-1.12）. PGE abundance was characterized by the PGE-type distribution patterns, enriching platinum （Pt）, palladium （Pd）, ruthenium （Ru） and osmium （Os）. The Pt/Pd ratio was 0.8, which is close to the ratios of seawater and ultramafic rocks. All of these geochemical features suggest that the mineralization was triggered by hydrothermal activity in an extensional setting in the context of break-up of the Rodinian supercontinent.

关键词： geochemistry polymetallic layer hydrothermal activity Lower Cambrian

Comparative Study on the Properties of Inorganic Silicate and Organic Phenolic Prepolymer Modified Poplar Wood by Vacuum Cycle Pressurization

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Journal of Renewable Materials 2022年第9期10卷 2451-2463页

作者： Pengfei guan ping Li Yiqiang wu Xingong Li guangming Yuan Yingfeng Zuo College of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha410004China College of Furniture and Art Design Central South University of Forestry and TechnologyChangsha410004China

To enhance mechanical properties and improve flame retardancy and smoke suppression of fast-growing poplar wood in wood applications,the wood was impregnated and *** organic phenolic prepolymer and inorganic sodium silicate was used as contrasting impregnation modifiers and wood samples were impregnated by a bionic“respiration”method with alternating positive and negative *** weight percentage gain,density increase ratio,mechanical properties(bending and compressive strength and hardness),and water absorption rate of inorganic and organic-impregnated modified poplar wood(IIMPW and OIMPW,respectively)were compared and these properties in IIMPW were found to be higher than those of OIMPW with the exception of the water absorption rate which was lower than the *** was attributed to the superior absorption of sodium silicate that also improved the impregnation,reinforcement,and dimensional stability in the *** chemical structure,crystalline structure,internal morphology,flame retardancy,smoke suppression,and thermal stability of IIMPW and OIMPW were characterized by FT-IR,XRD,SEM,CONE,and ***-IR and XRD results showed that,although IIMPW cellulose crystallinity reduced the most,more chemical bonds were come into being in IIMPW,which explained the better physical and mechanical properties of *** with OIMPW,IIMPW had better flame retardant and smoke suppression performance.

关键词： Poplar wood sodium silicate impregnation modification mechanical properties dimensional stability flame retardancy and smoke suppression

Thrombolysis and extracorporeal cardiopulmonary resuscitation for cardiac arrest due to pulmonary embolism:A case report

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World Journal of Critical Care Medicine 2025年第1期14卷 111-117页

作者： guan-Xing Yuan Zhi-ping Zhang Jia Zhou Department of Emergency Wuhan Asia General HospitalWuhan 430056Hubei ProvinceChina Department of Neurosurgery Central Theater Command General HospitalWuhan 430000Hubei ProvinceChina

BACKGROUND Cardiac arrest caused by acute pulmonary embolism(PE)is the most serious clinical circumstance,necessitating rapid identification,immediate cardiopulmonary resuscitation(CPR),and systemic thrombolytic *** CPR(ECPR)is typically employed as a rescue therapy for selected patients when conventional CPR is failing in settings where it can be *** SUMMARY We present a case of a 69-year-old male who experienced a prolonged cardiac arrest in an ambulance with pulseless electrical *** arrival at the emergency department with ongoing manual chest compressions,bedside pointof-care ultrasound revealed an enlarged right ventricle without *** PE was suspected as the cause of cardiac arrest,and intravenous thrombolytic therapy with 50 mg tissue plasminogen activator was administered during mechanical chest *** 31 minutes of CPR,return of spontaneous circulation was not achieved until 8 minutes after initiation of Veno-arterial extracorporeal membrane oxygenation(ECMO)*** ECMO support,the hemodynamic status and myocardial contractility significantly ***,the patient ultimately did not survive due to intracerebral hemorrhagic complications,leading to death a few days later in the *** This case illustrates the potential of combining systemic thrombolysis with ECPR for refractory cardiac arrest caused by acute PE,but it also highlights the increased risk of significant bleeding complications,including fatal intracranial hemorrhage.

关键词： Pulmonary embolism Cardiac arrest Thrombolytic therapy Cardiopulmonary resuscitation Extracorporeal membrane oxygenation Intracranial hemorrhage Case report

Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant

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Rare Metals 2013年第4期32卷 425-430页

作者： Song-ping wu School of Chemistry and Chemical Engineering South China University of Technology

Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.

关键词： Solvent extraction Palladium 2-n-octyl-4-isothiazolin-3-one OIT Stripping

Development of a unified viscoplasticity constitutive model based on classical plasticity theory

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Science China(Technological Sciences) 2009年第5期52卷 1248-1253页

作者： guan ping LIU ChangChun Lü HeXiang College of Architectural Engineering Dalian UniversityDalian 116622China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China

The traditional unified viscoplasticity constitutive model can be only applied to metal *** study of the unified constitutive theory for metal materials has discovered the correlation between the classical plasticity theory and the unified viscoplasticity constitutive model,thus leading to the con-cepts of the classic plastic potential and yield surface in the unified constitutive ***,this research has given the continuous expression of the classical plastic multiplier and presented the corresponding constructive method,which extends its physical significance and lays down a good foundation for the application of the unified constitutive theory to the material analysis in more *** paper also introduces the unified constitutive model for metal materials and *** numerical simulation indicates that the construction should be both reasonable and practical.

关键词： viscoplasticity classical plasticity unified constitutive model plastic potential yield surface

A unified viscoplasticity constitutive model based on irreversible thermodynamics

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Science China(Technological Sciences) 2008年第4期51卷 378-385页

作者： LIU ChangChun Lü HeXiang guan ping State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Prediction&Control Key Laboratory on Complicated Structure System Dalian UniversityDalian 116622China

A unified viscoplasticity constitutive model for metal materials is developed within the framework of irreversible thermodynamics, and an expression for the Helmholtz free energy function involving the parameters reflecting kinematic hardening and isotropic hardening is given. At the same time a non-associated flow potential function including the corresponding state variables is also given, from which the flow equation and the evolution equations of the internal state variables are derived. Thus, a general theoretical framework constructing a unified viscoplasticity constitutive model is given. Compared with the typical unified viscoplasticity constitutive models, the presented model evidently satisfies the irreversible thermodynamics laws. Moreover, this method not only provides a new theoretical foundation for further development of the unified viscoplasticity constitutive model, but also gives a new theoretical framework for the stress-strain analysis of more materials.

关键词： irreversible thermodynamics viscoplasticity unified constitutive kinematic hardening isotropic hardening

Optimal dynamical systems of Navier-Stokes equations based on generalized helical-wave bases and the fundamental elements of turbulence

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Science China(Physics,Mechanics & Astronomy) 2016年第11期59卷 61-69页

作者： NaiFu Peng Hui guan ChuiJie wu State Key Laboratory of Structural Analysis for Industrial Equipment School of Aeronautics and AstronauticsDalian University of Technology State Key Laboratory for Turbulence and Complex Systems Center for Applied Physics and TechnologyCollege of Engineering Peking University College of Meteorology and Oceanography PLA University of Science and Technology

In this paper, we present the theory of constructing optimal generalized helical-wave coupling dynamical systems. Applying the helical-wave decomposition method to Navier-Stokes equations, we derive a pair of coupling dynamical systems based on optimal generalized helical-wave bases. Then with the method of multi-scale global optimization based on coarse graining analysis, a set of global optimal generalized helical-wave bases is obtained. Optimal generalized helical-wave bases retain the good properties of classical helical-wave bases. Moreover, they are optimal for the dynamical systems of Navier-Stokes equations, and suitable for complex physical and geometric boundary conditions. Then we find that the optimal generalized helical-wave vortexes fitted by a finite number of optimal generalized helical-wave bases can be used as the fundamental elements of turbulence, and have important significance for studying physical properties of complex flows and turbulent vortex structures in a deeper level.

关键词： optimal dynamical systems helical-wave decomposition fundamental elements of turbulence vortex structures

LINEAR REGRESSION OF INTERVAL-VALUED DATA BASED ON COMPLETE INFORMATION IN HYPERCUBES

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Journal of Systems Science and Systems Engineering 2012年第4期21卷 422-442页

作者： Huiwen WANG Rong guan Junjie wu Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations School of Economics and ManagementBeihang University

Recent years have witnessed an increasing interest in interval-valued data analysis. As one of the core topics, linear regression attracts particular attention. It attempts to model the relationship between one or more explanatory variables and a response variable by fitting a linear equation to the interval-valued observations. Despite of the well-known methods such as CM, CRM and CCRM proposed in the literature, further study is still needed to build a regression model that can capture the complete information in interval-valued observations. To this end, in this paper, we propose the novel Complete Information Method （CIM） for linear regression modeling. By dividing hypercubes into informative grid data, CIM defines the inner product of interval-valued variables, and transforms the regression modeling into the computation of some inner products. Experiments on both the synthetic and real-world data sets demonstrate the merits of CIM in modeling interval-valued data, and avoiding the mathematical incoherence introduced by CM and CRM.

关键词： Interval-valued data linear regression complete information method (CIM) hypercubes

A study of a three-dimensional self-propelled flying bird with flapping wings

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Science China(Physics,Mechanics & Astronomy) 2015年第9期58卷 52-67页

作者： ZHU LinLin guan Hui wu ChuiJie State Key Laboratory of Structural Analysis for Industrial Equipment School of Aeronautics and Astronautics Dalian University of Technology College of Meteorology and Oceanography PLA University of Science and Technology

In this paper, a study of a three-dimensional(3D) self-propelled bionic flying bird in a viscous flow is carried out. This bionic bird is propelled and lifted through flapping and rotating wings, and better flying can be achieved by adjusting the flapping and rotation motion of wings. In this study, we found that the bird can fly faster forward and upward with appropriate center of rotation and oscillation without more energy consumption and have perfect flight performance at a certain angle of attack by adjusting the center of oscillation. The study utilizes a 3D computational fluid dynamics package which constitutes combined immersed boundary method and the volume of fluid method. In addition, it includes adaptive multigrid finite volume method and control strategy of swimming and flying.

关键词： self-propelled bird flying numerical simulation three-dimensional