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Equilibrium and mechanism studies of gold(Ⅰ)extraction from alkaline aurocyanide solution by using fluorine-free ionic liquids

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Rare Metals 2021年第7期40卷 1987-1994页

作者： Ya-Ting Wang Men liu Nian Tang Sheng-jian Li Yan Sun Shi-xiong Wang Xiang-Jun Yang Key Laboratory of Medicinal Chemistry for Natural Resource(Yunnan University) Ministry EducationSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China

Solvent extraction based on ionic liquids is generally considered to be an environmentally benign and effective technology for gold(Ⅰ)*** aim of this work is to study gold(Ⅰ)extraction from aurocyanide solution using fluorine-free ionic liquids[A336][SCN],[A336][MTBA]and[A336][Mal].Various factors that affect gold(Ⅰ)extraction(including concentration of ionic liquids,equilibrium pH,concentration of the modifier tributyl phosphate(TBP),reaction time and initial concentration of gold in an aqueous solution)were studied and *** results indicate that the three Aliquat336-based ionic liquids all exhibit excellent behaviors for gold(Ⅰ)*** than 99.8%of gold(Ⅰ)can be extracted from the aqueous phase into the ionic liquid *** gold-loaded ionic liquids were characterized using infrared spectroscopy and mass spectrometry to study the extraction mechanism of gold(Ⅰ).The results revealed that extraction of gold(Ⅰ)into the ionic liquid phase was based on an exchange reaction between the anion Au(CN)2-in aqueous solution and the anion SCN-in ionic liquid[A336][SCN].The logarithmic relationship between distribution coefficient and TBP concentration indicates that two TBP molecules are involved in the formation of the extracted *** extracted complex was determined to be A336^(+)·Au(CN)_(2)^(-)·2 *** addition,the gold(Ⅰ)-loaded ionic liquids can be efficiently stripped using NH4 SCN,2-methylthiobenzoic acid and methyl *** results establish that Aliquat 336-based ionic liquids have potential application prospects in gold(Ⅰ)recovery from cyanide solutions.

关键词： Gold(Ⅰ) Solvent extraction Ionic liquid Alkaline aurocyanide solution

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Layered space time codes and capacity analysis in correlated fading channels with distributed antenna system

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 28-35页

作者： xiong Fei ZHANG jian-hua ZHANG Ping Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education 13eijing University of Posts and Telecommunications Beijing 100876 China

In this paper we have investigated the performance of downlink generalized distributed antenna system （GDAS）. Under the assumption of spatial correlated fading conditions, we have derived the numeric expression of correlated coefficients according to series of Bessel function, and have lifted the range restriction of the mean angle of incident. Moreover, the architecture of distributed generalized layered space time codes （GLST） has been considered in order to achieve both multiplexing gain and diversity gain while we have used basis vector from null space instead of orthogonal set to obtain the same system performance but with lower complexity. Furthermore, in order to maximize the capacity, Gerschgorin circles based fast antenna selection algorithms have been evaluated including a discussion of those simulation results.

关键词： GDAS GLST capacity correlated fading channel

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DOA estimation and mutual coupling calibration with the SAGE algorithm

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Chinese Journal of Aeronautics 2014年第6期27卷 1538-1543页

作者： xiong Kunlai liu Zhangmeng liu Zheng jiang Wenli College of Electronic Science and Engineering National University of Defense Technology

In this paper, a novel algorithm is presented for direction of arrival（DOA） estimation and array self-calibration in the presence of unknown mutual coupling. In order to highlight the relationship between the array output and mutual coupling coefficients, we present a novel model of the array output with the unknown mutual coupling coefficients. Based on this model, we use the space alternating generalized expectation-maximization（SAGE） algorithm to jointly estimate the DOA parameters and the mutual coupling coefficients. Unlike many existing counterparts, our method requires neither calibration sources nor initial calibration information. At the same time,our proposed method inherits the characteristics of good convergence and high estimation precision of the SAGE algorithm. By numerical experiments we demonstrate that our proposed method outperforms the existing method for DOA estimation and mutual coupling calibration.

关键词： Array self-calibration Convergence Direction of arrival estima-tion Mutual coupling Space alternating generalized expectation-maximization algorithm

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Multi-slice spiral computed tomography in diagnosing unstable pelvic fractures in elderly and effect of less invasive stabilization

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World Journal of Clinical Cases 2022年第14期10卷 4470-4479页

作者： jian-Guo Huang Zhi-Yuan Zhang Liang Li Guang-Bao liu xiong Li Department of Orthopedics Sanya Hospital of Traditional Chinese MedicineSanya 572000Hainan ProvinceChina Department of Orthopedics Xi’an Honghui HospitalXi’an 710024Shaanxi ProvinceChina Department of Radiology Sanya Hospital of Traditional Chinese MedicineSanya 572000Hainan ProvinceChina Department of Traumatic Orthopedics Sports Medicine Yan'an Hospital of Traditional Chinese MedicineYan'an 716000Shaanxi ProvinceChina

BACKGROUND Older people are more likely to experience pelvic fractures than younger ***-slice spiral computed tomography(CT)uses three-dimensional(3D)reconstruction technology to generate 3D images that can clearly demonstrate the 3D space of fractures and detect fractures at a higher *** To investigate the clinical value of multi-slice spiral CT 3D reconstruction in the diagnosis of unstable pelvic fractures in the elderly as well as the effect of less invasive *** A total of 86 patients with unstable pelvic fractures treated between March 2016 and March 2019 underwent femoral supracondylar bone traction before *** radiography and multi-row spiral CT were performed successively once the patient’s vital signs and hemodynamic indices were *** processing of the original data was performed to obtain 3D reconstruction images and determine the vertical displacement of the *** basic or complete reduction,minimally invasive internal fixation using hollow lag screws was *** detection rates of fracture location and classification by X-ray and CT reconstruction were *** were divided into two groups according to the presence or absence of preoperative 3D reconstruction to compare postoperative reduction,wound healing time,fracture healing time,hospitalization time,visual analog scale(VAS)score,poor internal fixation,and functional *** The diagnostic coincidence rates of X-rays for pubic symphysis,ilium wing,sacroiliac periarticular,and sacral fractures were lower than those of CT *** coincidence rate of CT reconstruction in the clinical classification of pelvic fractures was 100%,whereas 11 cases were misdiagnosed by X-ray;the total coincidence rate was 87.21%.The total excellent and good rates of postoperative reduction were significantly higher in the study group than in the control group(P<0.05).The wound healing,fracture healing,and hospitalization times wer

关键词： Multi-slice spiral computed tomography Three-dimensional reconstruction Unstable pelvic fracture Minimally invasive internal fixation Diagnostic value

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Impact of diabetes mellitus on pneumonia mortality in a senior population:results from the NHANES III follow-up study

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Journal of Geriatric Cardiology 2013年第3期10卷 267-271页

作者： jian liu Brock University 500 Glenridge Ave. St. Catharines 0ntario Canada

Objective To examine whether diabetes mellitus increases the risk of pneumonia mortality among seniors in the U.S. general popula-tion. Methods&Results The NHANES III follow-up study data were used. After excluding individuals from other minorities, being hos-pitalized with pneumonia in the previous year at baseline, or death of pneumonia during the first year of follow-up, a total of 3,707 subjects aged 65 years or older (1,794 men and 1,913 women) who had no missing information on variables for the analysis were included. Approxi-mately 16% of seniors at baseline were diabetics, which was defined as either having been diagnosed by a physician, currently taking pills/insulin lowering blood glucose, or HbA1c higher than 6.4%. During an average 11 years of follow-up, a total of 98 deaths due to pneu-monia were recorded (ICD-10:J12-J18). Cox-regression models were used to estimate the risk association between pneumonia mortality and diabetes mellitus. After adjustment for the covariates at baseline, the hazard ratios of pneumonia death were 1.30 (95%CI:0.64-2.70) for pre-diabetics and 2.28 (95%CI:1.18-4.39) for diabetics, respectively. Among those covariates, only age (HR (95%CI);1.16 (1.13-1.20)), gender as female (0.35 (0.22-0.61)) and physical fitness measured as having no problem walking 1+mile during the previous month (0.38 (0.20-0.67)) reached statistical significance. Conclusions The results suggest that diabetes mellitus is a strong risk predictor of pneumonia mortality and the evaluation of physical fitness may also be useful in the risk prediction of pneumonia mortality for seniors.

关键词： Diabetes mellitus Follow-up Mortality Physical fitness Pneumonia Senior

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Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane

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Journal of Energy Chemistry 2024年第4期91卷 331-344页

作者： Tongtong Wu Yuechang Wei Jing xiong Yitao Yang Zhenpeng Wang Dawei Han Zhen Zhao jian liu State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing 102249China

It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower ***,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active *** co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,*** mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature *** is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application.

关键词： 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species

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A new species of the genus Batrachuperus (Urodela:Hynobiidae) from Southwestern China

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Zoological Research 2020年第5期41卷 589-594页

作者： jian-Li xiong Wei Luo Xiao-Mao Zeng College of Animal Science and Technology Henan University of Science and TechnologyLuoyangHenan 471023China Chengdu Institute of Biology Chinese Academy of Sciences'ChengduSichuan 610041China

DEAR EDITOR,A new stream salamander species,Batrachuperus daochengensis ***.,from southwestern China,is described herein based on morphological and molecular *** phylogeny derived from the mitochondrial gene together ... 详细信息

关键词： herein Molecular southwestern

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EFFECTS OF DIFFERENT FUNCTIONALIZATION SCHEMES ON THE INTERFACIAL STRENGTH OF CARBON NANOTUBE POLYETHYLENE COMPOSITE

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Acta Mechanica Solida Sinica 2015年第3期28卷 277-284页

作者： Tan Xiao Juqing liu Huifang xiong Architecture and Civil Engineering Institute Guangdong University of Petrochemical Technology Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM) Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM)Nanjing Tech University (NanjingTech) School of Computer and Electronic Information Guangdong University of Petrochemical Technology

The mechanical performance of carbon nanotube （CNT） reinforced polymer com- posites is primarily controlled by the dispersive capacity and interracial shear strength of CNTs in polymer matrices. CNT functionalizations will improve dispersion and strengthen interracial bonding of CNTs in matrices. To understand the effects of different functionalization schemes on the interracial strength of CNT-polymer composites, pullout of the covalent, noncovalent, and mixed functionalized single-walled carbon nanotube （SWCNT） from polyethylene （PE） matrix was simulated by using molecular dynamics, respectively. The results show that the SWCNT-PE interracial shear strength is significantly improved by SWCNT functionalizations, particularly by mixed functionalization.

关键词： interracial shear strength carbon nanotubes nano composites molecular dynamics

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Credit Rationing and the Simulation of Bank-Small and Medium Sized Firm Artificial Credit Market

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Journal of Systems Science & Complexity 2016年第4期29卷 991-1017页

作者： liu Xuefeng ZHANG Wei xiong xiong SHEN Dehua ZHANG Yongjie College of Management and Economics Tianjin UniversityTianjin 300072China Key Laboratory of Computation and Analytics of Complex Management Systems(CA CMS) Tianjin UniversityTianjin 300072China Departament d'Economia Universitat Jaume ICastellSn de la Plana12071Spain.

By analyzing the financing difficulties faced by the small and medium-sized firms, the paper built an artificial credit markets with the agent-based computational modeling to simulate the real world credit transactions. There are firms, banks, different risk-type projects as well as legal and supervision environments in which debt contracts constitute the financial instruments. The simulation results show that the number of collateral, average success probability of projects, and the prime interest rate have materially impact on bank's average profit, bank's capital, the overall interest rate,the number of borrowing firms, loan size, and the degree of credit rationing. These results in line with those of the classical S-W model in the sense that the relationship between bank profits and interest rates is non-monotonic as well as the relationship between credit rationing and interest rates. And thus there is an adverse selection effect in credit rationing theory.

关键词： Agent-based computational finance artificial credit market credit rationing small- and medium-sized firms.

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Rapid Hydrogen Transportation Along Grain Boundary in Nickel

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 615-620页

作者： Yongli Wang Liangyin xiong Shi liu Department of Special Environment Materials Institute of Metal ResearchChinese Academy of Sciences

The permeability and diffusivity of hydrogen in directionally solidified polycrystalline and single crystal nickel foils were measured by gas permeation *** results showed that both hydrogen diffusivity and permeability were higher in directionally solidified nickel specimen than those in single crystal one at the temperature ranging from 300 to480 °C,and confirmed the existence of short-circuit diffusion along the grain boundaries（GBs） in the directionally solidified *** results suggested that the rapid diffusion along GBs was more obviously characterized in terms of higher permeability rather than higher *** contribution of grain boundary to hydrogen transportation was represented by the differences of diffusivity（and permeability） in single crystal nickel and directionally solidified *** modifying the Fick＇s first diffusion law and counting the grain boundary density,the hydrogen diffusivity and permeability of rapid diffusion along GBs were *** results suggested both the diffusivity and permeability fit the Arrhenius relationship well at different temperature.

关键词： Hydrogen trapping Hydrogen embrittlement Grain boundary diffusion Nickel

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