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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 452-457页

作者： Meng Chen Wen-le Ao Chang-song dai Tao Tao Jun Yang College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 15001 China

A new co-precipitation route was proposed to synthesize LiNi0.8A10.2-xTixO2 （x=0.0-0.20） cathode materials for lithium ion batteries, with Ni（NO3）2, Al（NO3）3, LiOH·H2O, and TiO2 as the starting materials. Ultrasonic vibration was used during preparing the precursors, and the precursors were protected by absolute ethanol before calcination in the air. The influences of doped-Ti content, calcination temperature and time, additional Li content, and ultrasonic vibration on the structure and properties of LiNi0.8A10.2-xTixO2 were investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and charge-discharge tests, respectively. The results show that the optimal molar fraction of Ti, calcination temperature and time, and additional molar fraction of Li for LiNi0.8A10.2-xTixO2 cathode materials are 0.1,700℃, 20 h, and 0.05, respectively. Ti doping facilitates the formation of the α-NaFeO2 layered structure, and ultrasonic vibration improves the electrochemical performance of LiNi0.8A10.2-xTixO2.

关键词： lithium ion batteries cathode materials ultrasonic vibration co-precipitation electrochemical properties

Shear Behaviors of Steel-Plate Connections for Timber-Concrete Composite Beams with Prefabricated Concrete Slabs

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Journal of Renewable Materials 2023年第1期11卷 349-361页

作者： Benkai Shi Bowen Huang Huifeng Yang Yongqing dai Sijian Chen Nanjing Tech University Nanjing211816China

To promote the development of timber-concrete composite(TCC)structures,it is necessary to propose the assembly-type connections with high assembly efficiency and shear *** article presented the experimental results of the innovative steel-plate connections for TCC beams using prefabricated concrete *** steel-plate connections consisted of the screws and the *** steel-plates were partly embedded in the concrete *** concrete slabs and the timber beams were connected by screws through the *** parameters researched in this article included screw number,angle steel as the reinforcement for anchoring,and shallow notches on the timber surface to restrict the slip of the *** results were discussed in terms of failure modes,ultimate bearing capacities,and slip *** was found that increasing the number of screws could lead to the obvious improvement on the ultimate bearing capacities and the slip moduli at the ultimate state;and the angle steel as the reinforcement showed the slight influence on the ultimate bearing capacities and the slip *** application of the shallow notch can greatly improve the ultimate bearing capacities and the slip *** calculation models for the ultimate bearing capacities and the slip moduli of the steel-plate connections with and without shallow notches were proposed,which showed good accuracy compared with the experimental results.

关键词： Timber-concrete composites steel-plate connections prefabricated shallow notches push-out tests

A Frameless Network Architecture for the Way Forward of C-RAN

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China Communications 2016年第6期13卷 154-166页

作者： Xiaodong Xu Zhao Sun Xun dai Xiaofeng Tao Ping Zhang National Engineering Laboratory for Mobile Network Security Beijing University of Posts and Telecommunications

The key technologies involved in the evolution of the Cloud-based Radio Access Network(C-RAN) are discussed in this paper. Taking the Frameless Network Architecture(FNA) as a starting point, a cell-lessbased network topology for a multi-tier Heterogeneous Network(Het Net) and ultra-dense network is proposed. The FNA network topology modeling is researched with centralized processing and distributed antenna deployments. The Antenna Element(AE) is released as a new dimensional radio resource that is included in the centralized Radio Resource Management(RRM) processes. This contributes to the on-demand user-centric serving-set associations with cell-edge effect elimination. The Control Plane(CP) and User Plane(UP) separation and adaptation are introduced for energy efficiency improvements. The centralized RRM and different optimization goals are discussed for fully exploring the merits from the centralized computing of C-RAN. Considering the complexity, near-optimal approaches for specific users' Quality-of-Service(Qo S) requirements are addressed. Finally, based on the research highlighted above, the way forward of C-RAN evolution is discussed.

关键词： C-RAN frameless network architecture user-centric control plane and user plane adaptation centralized radio resource management optimization

Modeling and simulation of urea-water-solution droplet evaporation and thermolysis processes for SCR systems

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Chinese Journal of Chemical Engineering 2016年第8期24卷 1065-1073页

作者： Xubo Gan Dongwei Yao Feng Wu Jiawei dai Lai Wei Xingwen Li Institute of Power Machinery and Vehicular Engineering Zhejiang University

A reliable mathematical model of urea-water-solution(UWS) droplet evaporation and thermolysis is *** well known Abramzon–Sirignano evaporation model is corrected by introducing an adjustment coefficient considering the different evaporation behaviors of UWS droplet at different ambient temperatures. A semidetailed kinetic scheme of urea thermolysis is developed based on Ebrahimian's work. Sequentially, the evaporation characteristics, decomposition efficiency of a single UWS droplet and deposit formation are simulated. As a result, the relation of evaporation time, relative velocity, exhaust temperature and droplet initial diameter is presented. Synchronously, it indicates that temperature is the decisive factor for urea thermolysis. Different temperatures result in different deposit components, and deposit yield is significantly influenced by temperature and decomposition time. The current work can provide guidance for designing urea injection strategy of SCR systems.

关键词： SCR UWS evaporation Urea thermolysis Semi-detailed kinetic Simulation

Numerical Investigation on the Aerodynamic Noise Generated by a Simplified Double-Strip Pantograph

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Fluid Dynamics & Materials Processing 2022年第2期18卷 463-480页

作者： Jiawei Shi Shuai Ge Xiaozhen sheng State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu610031China School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China

In order to understand the mechanism by which a pantograph can generate aerodynamic noise and grasp its farfield characteristics,a simplified double-strip pantograph is analyzed ***,the unsteady flow field around the pantograph is simulated in the frame of a large eddy simulation(LES)*** the location of the main noise source is determined using surface fluctuating pressure data and the vortex structures in the pantograph flow field are analyzed by means of the *** on this,the relationship between the wake vortex and the intensity of the aerodynamic sound source on the pantograph surface is ***,the far-field aerodynamic noise is calculated by means of the Ffowcs Williams-Hawkings(FW-H)equation,and the contribution of each component to total noise and the frequency spectrum characteristics are *** results show that on the pantograph surface where vortex shedding or interaction with the wake of upstream components occurs,the pressure fluctuation is more intense,resulting in strong dipole *** far-field aerodynamic noise energy of the pantograph is mainly concentrated in the frequency band below 1500 *** peaks in the frequency spectrum are mainly generated by the base frame,balance arm and the rear strip,which are also the main contributors to the aerodynamic noise.

关键词： Pantograph aerodynamic noise vortex structures noise source FW-H equation

Outcomes and possible risk factors associated with axis alignment and rotational stability after implantation of the Toric implantable collamer lens for high myopic astigmatism

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 459-465页

作者： Xun-Lun sheng, De-Jun Zhu Department of Ophthalmology People's Hospital of Ningxia Hui Autonomous Region Yinchuan 750001 Ningxia Hui Autonomous Region China Department of Ophthalmology the Affiliated Hospital of Ningxia Medical University Yinchuan 750004 Ningxia Hui Autonomous Region China

AIM: To assess the visual outcomes and possible risk factors associated with axis alignment and rotational stability after implantation of Toric implantable collamer lens (TICL) for the correction of high myopic astigmatism. METHODS: In this prospective, nonrandomized clinical study, 54 consecutive eyes of 29 patients with high myopic astigmatism received TICL implantation. To evaluate postoperative axis deviation from the intended axis, a digital anterior segment photograph was taken. The ultrasound biomicroscopy(UBM) was used to observe footplate-position. RESULTS: After mean follow-up of 8.6 months, mean manifest refractive cylinder (MRC) decreased 79.3% from (-1.88 +/- 1.49)D preoperatively to (0.39 +/- 0.61)D postoperatively. MRC within 1.00D occurred in 68.5% (37/54) of eyes, whereas 48.1% (26/54) had MRC within 0.50D. Mean manifest refraction spherical equivalent (MRSE) changed from (-1208 +/- 422)D preoperatively to (-0.41 +/- 0.61)D postoperatively. Uncorrected binocular vision of 20/20 or better occurred in 72.2% (39/54) of patients compared with binocular best-corrected visual acuity (BCVA) of 20/20 or better in 44.4% (24/54) preoperatively. The mean difference between intended and achieved TICL axes was (6.96 +/- 8.37)degrees. Footplates of TICLs were in the ciliary sulcus in 22 eyes (46.3%), below the ciliary sulcus in 32 eyes (53.7%). The angle of TICL rotation had significant correlation with the footplates-position (t = 2.127; P=0.045) and the postoperative TICL vaulting (r=-0.516; P=0.000). CONCLUSION: The results of our study further support the safety, efficacy and predictability of TICL for the correct high myopic astigmatism. The footplate-position of TICL and vault value should be taken into consideration as two possible risks factors for TICL rotation.

关键词： astigmatism myopia Toric

Numerical Simulation of the Fractional-Order Lorenz Chaotic Systems with Caputo Fractional Derivative

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1371-1392页

作者： Dandan dai Xiaoyu Li Zhiyuan Li Wei Zhang Yulan Wang School of Physics and Electronic Information Engineering Jining Normal UniversityJining012000China Department of Mathematics Inner Mongolia University of TechnologyHohhot010051China Institute of Economics and Management Jining Normal UniversityJining012000China

Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to *** on this problem,this paper introduces a high-precision numerical *** complex dynamic behavior of fractional-order Lorenz chaotic systems are shown by using the present *** observe some novel dynamic behavior in numerical experiments which are unlike any that have been previously discovered in numerical experiments or theoretical *** investigate the influence of α_(1),α_(2),α_(3) on the numerical solution of fractional-order Lorenz chaotic *** simulation results of integer order are in good agreement with those of *** simulation results of numerical experiments demonstrate the effectiveness of the present method.

关键词： Novel complex dynamic behavior numerical simulation fractional-order lorenz chaotic systems high-precision

Management of non-alcoholic fatty liver disease patients with sleep apnea syndrome

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World Journal of Gastroenterology 2022年第43期28卷 6099-6108页

作者： Wei sheng Guang Ji Li Zhang Institute of Digestive Diseases Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China

Nonalcoholic fatty liver disease(NAFLD)is strongly associated with sleep apnea syndrome(SAS).Many NAFLD patients have SAS,and obstructive sleep apnea hypopnea syndrome is also considered to be an independent risk factor for NAFLD,as it contributes to the progression of NAFLD via oxidative stress,lipid peroxidation,inflammation,and insulin *** review aims to provide some recommendations for the management of NAFLD patients with SAS,including diet,exercise,weight loss,and continuous positive airway *** review also highlights the importance of effective strategies in NAFLD prevention and treatment.

关键词： Nonalcoholic fatty liver disease Sleep apnea syndrome Obesity Obstructive sleep apnea hypopnea syndrome Continuous positive airway pressure Management

Sequential extraction and compositional analysis of oil-bearing fluid inclusions in reservoir rocks from Kuche Depression, Tarim Basin

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Chinese Science Bulletin 2000年第S1期45卷 60-66页

作者： PAN Changchun FU Jiamo sheng Guoying Stale Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The free oils, adsorbed oils and oil-bearing fluid inclusions have been extracted separately and analyzed by GC and GC-MS in reservoir rock samples collected from the Kuche Depression. The results demonstrate that the molecular compositions of oil-bearing fluid inclusions are significantly different from those of the free oils (the current oils). Compared with the current oil, the oil-bearing fluid inclusions are characterized by relatively high values of parameters Pr/nC17 and Ph/nC18, low values of Pr/Ph, hopanes/steranes, C30-diahopane/C30-hopane and Ts/Tm, low content of C29Ts terpane and high maturities as indicated by C29 steranes 20S/(20R+20S). In addition, the oil-bearing fluid inclusions correlate very well with the oils in northern and central Tarim Basin, which were derived from Cambrian-Ordovician marine source rocks. The adsorbed oils appear to be an intermediate type between free oils and oil-bearing fluid inclusions. The above analytical data indicate that there are at least two

关键词： oil-bearing fluid inclusions adsorbed oils sequential extraction Kuche depression Tarim Basin.

Multidimensional stability of V-shaped traveling fronts in the Allen-Cahn equation

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Science China Mathematics 2013年第10期56卷 1969-1982页

作者： sheng WeiJie LI WanTong WANG ZhiCheng Natural Science Research Center Harbin Institute of Technology School of Mathematics and Statistics Lanzhou University

This paper is concerned with the multidimensional asymptotic stability of V-shaped traveling fronts in the Allen-Cahn equation under spatial decaying initial values. We first show that V-shaped traveling fronts are asymptotically stable under the perturbations that decay at infinity. Then we further show that there exists a solution that oscillates permanently between two V-shaped traveling fronts, which indicates that V-shaped traveling fronts are not always asymptotically stable under general bounded perturbations. Our main technique is the supersolutions and subsolutions method coupled with the comparison principle.

关键词： Allen-Cahn equation asymptotic stability multidimensional V-shaped traveling front