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Evaluation of Atmosphere–Land Interactions in an LES from the Perspective of Heterogeneity Propagation

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Advances in Atmospheric Sciences 2016年第5期33卷 571-578页

作者： Shaofeng liU Michael HINTZ xiaolong li Institute of Geophysics and Meteorology University of Cologne National Satellite Meteorological Center China Meteorological Administration

Atmosphere–land interactions simulated by an LES model are evaluated from the perspective of heterogeneity propagation by comparison with airborne measurements. It is found that the footprints of surface heterogeneity, though as 2D patterns can be dissipated quickly due to turbulent mixing, as 1D projections can persist and propagate to the top of the atmospheric boundary layer. Direct comparison and length scale analysis show that the simulated heterogeneity patterns are comparable to the observation. The results highlight the model＇s capability in simulating the complex effects of surface heterogeneity on atmosphere–land interactions.

关键词： atmosphere–land interaction heterogeneity large-eddy simulation

Universal and one-step visualization of latent fingermarks onvarious surfaces using hydrophilic cellulose membrane and dye aqueous solution

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Science China Chemistry 2017年第9期60卷 1250-1257页

作者： Qianhui Wei xiaolong li Xin Du Xueji Zhang Meiqin Zhang Research Center for Bioengineering&Sensing Technology University of Science&Technology BeoingBeijing 100083China

A high-resolution and universal method for the rapid visualization of latent fingermarks on a broad variety of surfaces has been achieved by simply combining hydrophilic cellulose membrane with dye aqueous solution. In this approach, the relatively hydrophobic characteristic of fingermark residue enable the deposit act as a “mask”, directing dye absorption processes to regions of both furrows without the ridge residues and bare cellulose membrane substrate. This effect during the spatially selective dye absorption generates a negative pattern of the fingermark within a few seconds to minutes depending on the properties of the substrates and fingermark types. It provides observation of latent fingermarks on cellulose membrane surface with high definition of level 2 and level 3 details used for personal identification purposes. It is also highly-efficient for visualizing the latent fingermarks lifted from various common (glass, carton, ceramic cup) and problematic (banknote, human skin and leather) surfaces by using transparent adhesive tape. To examine the generality of the proposed method, eight different kinds of dye aqueous solutions have been tested for developing latent fingermarks and they all provide very good results as expected. Moreover, this approach is easily used for aged fingermarks and natural fingermarks as well. Imaging may be accomplished visibly (by dye color) and topographically (using a microscope or a camera). This approach is a simple, rapid, non-destructive, safe, low-cost, universal and high resolution method compared with conventional approaches, so it demonstrates good potentiality in individual identity validation related applications. © 2017, Science China Press and Springer-Verlag Berlin Heidelberg.

关键词： Cellulose Hydrophilicity Membranes Substrates Visualization

An Intra-PAN Mobility Management Scheme for IPv6 over Low-Power Wireless Personal Area Networks

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Chinese Journal of Electronics 2014年第4期23卷 805-809页

作者： SHANG Xiaopu ZHANG Runtong li xiaolong Institute of Information Systems Beijing Jiaotong University

This paper proposes an intra-PAN mobility management scheme for IPv6 over Low-power wireless personal area networks(6Lo WPAN) on the basis of "networkbased" idea. We developed a tree-like network architecture which includes coordinate nodes for packet routing. All of the control messages are designed to transmit in link layer,and the sensor nodes are free to consider care-of address and the mobile nodes are unnecessary to deal with any mobility handoff messages. The simulation results show that this scheme efficiently cuts down the signaling cost and reduces the energy consumed by fixed nodes which can extend the life time of the whole Personal area networks(PAN).

关键词： Intra-PAN Mobility management IPv6 Wireless sensor networks 6Lo WPAN

Mathematical analysis of urban land use change in Xi'an city wall area by using parcel-level data

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Science China(Technological Sciences) 2019年第4期62卷 687-697页

作者： WANG ShuSheng ZHAO Zi liang XU YuQian li xiaolong State Key Laboratory of Green Building in Western China Xi'an University of Architecture and Technology College of Architecture Xi'an University of Architecture and Technology

Nowadays, more and more interdisciplinary approaches have been applied in urban planning, such as computer, mathematics and geography. However, the sophisticated mathematical methods such as transition matrix, joint-count, Bayes rules and Markov chain have not been deeply utilized in urban land use analysis. Furthermore, the newborn parcel-level urban land use data method has just been tested in a few cases and has not yet been adopted in ancient city area. Based on the above, this paper uses a series of mathematical methods and parcel-level urban land use data for quantification study in the Xi'an city wall area. Digitizing the maps compiled in 1935, 1963, 1995, 2007 and 2017 of the study area leads to the acquisition of the parcel-level urban land use data concerning the following four categories: Residential(R), Service(S), Culture(C) and Other(O). Then five parcel maps of different times will be built up. Through a series of mathematical analysis, the result shows that urban land use change in this area has three kinds of characteristics. For urban land use change speed, the period between 1995 and 2007 is the fastest while the period from 1963 to 1995 is the slowest. For the transition of urban land use, R and S are the main categories, and transition from R to S is the dominant change. Besides, dominated neighbors have positive effects on their transition. C is consistently increasing and has a clustering distribution. For the influence of other factors such as environment and policy, C is a special category that has the highest sensitivity to policies. The result clearly explains the data from the research into the evolution of urban land use in the study area work as a powerful support for land use planning and policy. The mathematical methods would provide a new perspective for the study in ancient Chinese cities.

关键词： urban space land use parcel maps transition matrix probability Markov chain

Flow and penetration behavior of submerged side-blown gas

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International Journal of Minerals,Metallurgy and Materials 2023年第6期30卷 1067-1077页

作者： Shuai Zhu Qiuyue Zhao xiaolong li Yan liu Tianci li Ting’an Zhang Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Shenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

To assess the widely used submerged side-blowing in pyrometallurgy,a high-speed camera-digital image processing-statistical approach was used to systematically investigate the effects of the gas flow rate,nozzle diameter,and inclination angle on the space-time distribution and penetration behavior of submerged side-blown gas in an air-water *** results show that the gas motion gradually changes from a bubbling regime to a steady jetting regime and the formation of a complete jet structure as the flow rate *** the flow rate is low,a bubble area is formed by large bubbles in the area above the *** the flow rate and the nozzle diameter are significant,a bubble area is formed by tiny bubbles in the area above the *** increased inclination angle requires a more significant flow rate to form a complete jet *** the sampling time,the dimensionless horizontal and vertical penetration depths are Gaussian *** the nozzle diameter and increasing the flow rate or inclination angle will increase the distribution range and *** correlations for a penetration depth with an error of±20%were obtained through dimensional *** dimensionless horizontal penetration depth of an argon-melt system in a 120 t converter calculated by the correlation proposed by the current study is close to the result calculated by a correlation in the literature and a numerical simulation result in the literature.

关键词： submerged side-blowing jet high-speed camera image processing dimensional analysis

Alternating Minimization Method for Total Variation Based Wavelet Shrinkage Model

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Communications in Computational Physics 2010年第10期8卷 976-994页

作者： Tieyong Zeng xiaolong li Michael Ng Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong KongChina Institute of Computer Science&Technology Peking UniversityBeijing 100871China

In this paper,we introduce a novel hybrid variational model which generalizes the classical total variation method and the wavelet shrinkage *** alternating minimization direction algorithm is then *** also prove that it converges strongly to the minimizer of the proposed hybrid ***,some numerical examples illustrate clearly that the new model outperforms the standard total variation method and wavelet shrinkage method as it recovers better image details and avoids the Gibbs oscillations.

关键词： Alternating minimization convergence Gibbs oscillation wavelet shrinkage total variation

Numerical optimization for blades of Intermig impeller in solid-liquid stirred tank

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Chinese Journal of Chemical Engineering 2021年第1期34卷 57-66页

作者： xiaolong li Hongliang Zhao Zimu Zhang Yan liu Ting’an Zhang Key Laboratory for Ecological Utilization of Multimetallic Mineral Ministry of EducationShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China School of Metallurgy&Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The multiphase flow in the solid-liquid tank stirred with a new structure of Intermig impeller was analyzed by computational fluid dynamics(CFD).The Eulerian multiphase model and standard k-ε turbulence model were adopted to simulate the fluid flow,turbulent kinetic energy distribution,mixing performance and power consumption in a stirred *** simulation results were also verified by the water model experiments,and good agreement was *** solid-liquid mixing performances of Intermig impeller with different blade structures were compared in *** results show that the improved Intermig impeller not only enhances the solid mixing and suspension,but also saves more than 20% power compared with the standard *** inner blades have relatively little influence on power and the best angle of inner blades is 45°,while the outer blades affect greatly the power consumption and the optimized value is 45°.

关键词： Intermig impeller Solid-liquid mixing Stirred tank CFD

Indole-tolerant Oxidation of 1,2-Diarylalkynes to 1,2-Diketone Derivatives

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Chemical Research in Chinese Universities 2015年第1期31卷 53-59页

作者： CHENG Xu li xiaolong WAN Weili HAO Wenmei HAI li WU Yong Key Laboratory of Drug-targeting of Ministry of Education Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041 P. R. China

A new indole-tolerant oxidation condition for the synthesis of 1,2-diketone derivatives from the corresponding 1,2-diarylalkynes was described. By screening a series of oxidation systems on alkynes linked with indole and different substituted aromatic ring, the DMSO/PdCl2/CuCl2 system afforded moderate to good yields despite the existence of electron-rich indole ring.

关键词： Selective oxidation 1,2-Diarylalkyne 1,2-Diketone

3D printing CO_(2)-activated carbon nanotubes host to promote sulfur loading for high areal capacity lithium-sulfur batteries

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Nano Research 2023年第6期16卷 8281-8289页

作者： Haiyan Chen Jingfeng liu Wanqiu Cao Hanna He xiaolong li Chuhong Zhang State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu 610065China

lithium-sulfur batteries(LSBs)have emerged as a promising high energy density system in miniaturized energy storage ***,serious issues rooted in large volume change(80%),poor intrinsic conductivity,“shuttle effect”of S cathode,and limited mass loading of traditional electrode still make it a big challenge to achieve high energy density LSBs in a limited ***,an innovative carbon dioxide(CO_(2))assisted three-dimensional(3D)printing strategy is proposed to fabricate threedimensional lattice structured CO_(2)activated single-walled carbon nanotubes/S composite thick electrode(3DP S@CNTs-CO_(2))for high areal capacity *** 3D lattice structure formed by interwoven CNTs and printed regular macropores can not only act as fast electron transfer networks,ensuring good electronic conductivity of thick electrode,but is beneficial to electrolyte infiltration,effectively boosting ion diffusion kinetics even under a high-mass *** addition,the subsequent hightemperature CO_(2)in-situ etching can induce abundant nanopores on the wall of CNTs,which significantly promotes the sulfur loading as well as its full utilization as a result of shortened ion diffusion *** to these merits,the 3DP S@CNTs-CO_(2)electrode delivers an impressive mass loading of 10 mg·cm^(−2).More importantly,a desired attribute of linearly scale up in areal capacitance with increased layers is observed,up to an outstanding value of 5.74 mAh·cm^(−2),outperforming most reported LSBs that adopt strategies that physically inhibit *** work provides a thrilling drive that stimulates the application of LSBs in new generation miniaturized electronic devices.

关键词： lithium-sulfur battery three-dimensional(3D)printing CO_(2)-activation thick electrode high areal capacity