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Mechanism of Mg2+ dissolution from olivine and serpentine: Implication for bioleaching of high-magnesium nickel sulfide ore at elevated pH

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International Journal of Minerals,Metallurgy and Materials 2019年第9期26卷 1069-1079页

作者： jian-zhi Sun jian-kang Wen Bo-wei Chen Biao Wu National Engineering Laboratory of Biohydrometallurgy GRINM Group Corporation Limited

To inhibit the dissolution of Mg^2+ during the bioleaching process of high-magnesium nickel sulfide ore, the effect of major bioleaching factors on the dissolution of Mg^2+ from olivine and serpentine was investigated and kinetics studies were carried out. The results indicated that the dissolution rate-controlling steps are chemical reaction for olivine and internal diffusion for serpentine. The most influential factor on the dissolution of Mg^2+ from olivine and serpentine was temperature, followed by p H and particle size. A novel method of bioleaching at elevated pH was used in the bioleaching of Jinchuan ore. The results showed that elevated pH could significantly reduce the dissolution of Mg^2+ and acid consumption along with slightly influencing the leaching efficiencies of nickel and cobalt. A model was used to explain the leaching behaviors of high-magnesium nickel sulfide ore in different bioleaching systems. The model suggested that olivine will be depleted eventually, whereas serpentine will remain because of the difference in the rate-controlling steps. Bioleaching at elevated pH is a suitable method for treating high-magnesium nickel sulfide ores.

关键词： olivine serpentine high-magnesium nickel sulfide ore bioleaching shrinking core model elevated pH

Effect of Stokes number on energy modulation of the fluid in turbulent particle-laden channel flows

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Journal of Hydrodynamics 2022年第3期34卷 510-521页

作者： zhi-feng Wu jian-zhao Wu Bo-fu Wang zhi-ming Lu Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai200072China

The effect of Stokes number on the kinetic energy(KE)budget in particle-laden turbulent channel flows is examined by conducting two-way coupled direct numerical simulations using the Eulerian-Lagrangian *** friction Reynolds number of the single phase channel flow is Re_(τ)=180,the particle mass loading and volume fraction areφ_(m)=0.2,φ_(v)≈10−4,and the Stokes numbers range from St^(+)=14–*** statistics show that due to the presence of solid particles,the mean velocity is reduced in the vicinity of the wall but enhanced in the outer region,and the off-streamwise intensity of fluctuated velocity and the Reynolds stress are reduced in the whole *** analysis on the budgets of turbulent kinetic energy(TKE)finds that the presence of particles induces a significant reduction on both the production and dissipation *** increasing Stokes number St^(+),both the production and dissipation rates exhibit non-monotonical trends,i.e.,both initially decrease for St^(+)*** suggests that the particle-induced suppression on TKE production and dissipation is the strongest nearly at St^(+)=*** is also found that particles act as an additional sink/source term in the budgets of both mean-flow kinetic energy(MKE)and *** addition,we investigate the influence of St^(+)on the“zero point”which indicates the balance of exchanging energy between the particle and fluid *** is shown that with increasing St^(+),the“zero point”moves toward the wall,suggesting that the position of perfect following between particle and fluid is closer to the wall with larger St^(+).The present results reveal the Stokes number effects on the spatial transport mechanisms of MKE,TKE in turbulent channel flows laden with inertial particles.

关键词： Particle-laden flows two-way coupling Stokes numbers kinetic energy budgets

Fault detection for sector-bounded non-linear systems with servo inputs and sensor stuck faults

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Journal of Control and Decision 2019年第3期6卷 147-165页

作者： Ying gu Xiao-jian Li School of Science Dalian Jiaotong UniversityDalianChina College of Information Science and Engineering Northeastern UniversityShenyangChina State Key Laboratory of Synthetical Automation of Process Industries Northeastern UniversityShenyangChina

This paper addresses the fault detection(FD)problem for discretetime sector-bounded non-linear systems with finite-frequency servo *** non-linear systems are firstly modelled as *** main contributions are that a novel FD filter which combines the finite-frequency H∞and H−indices is *** from the existing methods,the proposed FD scheme guarantees that the generated residuals are robust against the servo inputs in fault-free case and sensitive to them in faulty ***,the small sensor stuck faults including outagefaults can be *** this class of systems,the existing finite-frequency FD filter design methods are invalid.A new lemma is developed to characterise the system performances in finite-frequency *** addition,sufficient conditions for the existence of such a FD filter are derived by introducing slack variable and linear matrix inequalities ***,an example is presented to demonstrate the method and its effectiveness.

关键词： Fault detection servo inputs sensor stuck faults sector-bounded nonlinearity finite-frequency domain

Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats

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World Journal of Gastroenterology 2015年第2期21卷 484-490页

作者： Jun Chen Jia-Tian Dong Xiao-Jing Li Ye gu zhi-jian Cheng Yuan-Kun Cai Department of General Surgery Shanghai Fifth People’s HospitalFudan University Department of Pathology Shanghai Fifth People’s HospitalFudan University Clinical Base of Emergency Shanghai Fifth People’s HospitalFudan University

AIM: To observe the protective effect of glucagon-like peptide-2(GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective ***: Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase(ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14 th day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A(Ig A) expressed by plasma cells located in the small intestinal lamina propria were recorded for each ***: In the rat model, jaundice was obvious, and the rats' activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced Ig A expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group(P < 0.01). The increasing levels of the aforementioned markers were more significant in the obstructive jaundice group than in the GLP-2 group(P < 0.01).CONCLUSION: GLP-2 reduces intestinal mucosal injuries in obstructive jaundice rats, which might be attributed to increased intestinal Ig A and reduced bilirubin and endotoxin.

关键词： Intestinal mucosal barrier Glucagon-likepeptide-2

Research Progress and Future Perspectives on Rechargeable Na-O_(2) and Na-CO_(2) Batteries

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Energy & Environmental Materials 2021年第2期4卷 158-177页

作者： zhi Zheng Chang Wu Qinfen gu Konstantin Konstantinov Jiazhao Wang Institute for Superconducting and Electronic Materials University of WollongongWollongong NSW 2522Australia The Australian Synchrotron(ANSTO) 800 Blackburn RoadClayton VIC 3168Australia

Rechargeable sodium–oxygen(Na-O_(2))and sodium–carbon dioxide(Na-CO_(2))batteries have attracted intensive research attention in recent years owing to their advantages of high theoretical energy density,modest cost,abundance of sodium resources,and promising potential for achieving real sodium–air batteries in large-scale energy storage ***,current research on Na-O_(2)and Na-CO_(2)batteries is facing enormous challenges,such as low energy efficiency and limited cycle life,which are restricting their progress at the initial ***,understanding their working principles,and the chemical and electrochemical reactions of the electrodes is indispensable to achieve their practical application and even the goal of true sodium–air *** review aims to provide an overview of the research developments and future perspectives on Na-O_(2)and Na-CO_(2)batteries,which include the major aspects,such as working mechanisms,air cathode materials design strategies,sodium anode protection,and electrolyte ***,the remaining issues and future research directions are also thoroughly discussed and presented.

关键词： anode protection cathode materials electrolytes Na-CO_(2)batteries Na-O_(2)batteries

Applying a global pulse disturbance to eliminate spiral waves in models of cardiac muscle

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Chinese Physics B 2021年第7期30卷 157-162页

作者： jian Gao Changgui gu Huijie Yang Business School University of Shanghai for Science and TechnologyShanghai 200093China

Removal of spiral waves in cardiac muscle is necessary because of their threat to *** methods for this removal are to apply a local disturbance to the media,such as a periodic ***,most of these methods accelerate the beating of the cardiac muscle,resulting in the aggravation of the ventricular tachycardia,which directly threatens *** the present study,in order to clear off spiral waves,a global pulse-disturbance is applied to the media based on three models of cardiac *** is found that the spiral waves are eliminated and the frequency of the cardiac muscle is decreased in a short time,and finally,the state of the medium reaches the normal oscillation,which supports a target *** method sheds light on the removal of spiral waves in cardiac muscle and can prevent the ventricular tachycardia as well as the ventricular fibrillation.

关键词： ventricular fibrillation spiral wave pattern formation elimination

Notes on Application of WKB Method

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Communications in Theoretical Physics 2008年第10期50卷 864-866页

作者： gu Xiao-Yan SUN jian-Qiang Department of Physics East China University of Science and Technology Shanghai 200237 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

The notes here presented are of the modifications introduced in the application of WKB *** of two-and three-dimensional harmonic oscillator potential are revisited by WKB and the new formulationof quantization rule *** is found that the energy spectrum of the radial harmonic oscillator,which isreproduced exactly by the standard WKB method with the Langer modification,is also reproduced exactly without theLanger modification via the new quantization rule *** alternative way to obtain the non-integral Maslov indexfor three-dimensional harmonic oscillator is proposed.

关键词： WKB method quantization rules harmonic oscillator two-dimensional space

Effects of Atomic Mixing in Inertial Confinement Fusion by Multifluid Interpenetration Mix Model

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Communications in Theoretical Physics 2009年第12期52卷 1102-1106页

作者： gu jian-Fa YE Wen-Hua Institute of Applied Physics and Computational Mathematics Beijing 100094 China

The effects of atomic-level rnixing are systemically investigated in a multifluid interpenetration mix model ,and results are compared with the single-fluid model＇s simulations and experimental data. It is shown that increasing the model free parameter α, shock Mach number, and the initial density discontinuity makes the mix length and fraction of mixing particle increase, resulting in the lower shock temperatures compared with the results of single-fluid model without mixing. Recent high-compressibility direct-drive spherical implosions on OMEGA are simulated by the interpenetration mix modal. The calculations with atomic mixing between fuel and shell match quite well with the observations. Without considering any mixing, the calculated neutron yields and ion temperatures are overpredicted; while inclusion of the interpenetration mix model with the adjustable parameter α could fit the simulated neutron yields and ion temperatures well with experimental data.

关键词： multifluid interpenetration mix model atomic mixing inertial confinement fusion

An Improved Feasible QP-free Algorithm for Inequality Constrained Optimization

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Acta Mathematica Sinica,English Series 2012年第12期28卷 2475-2488页

作者： zhi Bin ZHU Jin Bao jian College of Mathematics and Computing Science Guilin University of Electronic Technology College of Mathematics and Informational Science Guangxi University College of Mathematics and Informational Science Yulin Normal University

In this paper, an improved feasible QP-free method is proposed to solve nonlinear inequality constrained optimization problems. Here, a new modified method is presented to obtain the revised feasible descent direction. In view of the computational cost, the most attractive feature of the new algorithm is that only one system of linear equations is required to obtain the revised feasible descent direction. Thereby, per single iteration, it is only necessary to solve three systems of linear equations with the same coefficient matrix. In particular, without the positive definiteness assumption on the Hessian estimate, the proposed algorithm is still global convergence. Under some suitable conditions, the superlinear convergence rate is obtained.

关键词： Inequality constrained optimization feasible QP-free method system of linear equations,global convergence superlinear convergence rate