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One-dimensional metallic, magnetic, and dielectric nanomaterialsbased composites for electromagnetic wave interference shielding

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Nano Research 2022年第10期15卷 9595-9613页

作者： Ya Cheng Wendong Zhu xiaofeng lu Ce Wang Alan G.MacDiarmid Institute College of ChemistryJilin UniversityChangchun 130012China

The excrescent electromagnetic(EM)radiation exposure in the air threatens human health and electronic equipment due to the abuse of EM waves in wireless telecommunication technology and electronic ***,electromagnetic interference(EMI)shielding materials are provided to solve the EM waves pollution *** particular,the appearance of onedimensional(1D)metallic,magnetic,and dielectric nanofillers will extremely reduce the density of EMI composite and enhance EMI protection performance because they can easily assemble to form complete two-dimensional(2D)or three-dimensional(3D)EMI network based on their high aspect ratio,large specific surface area,and additional attenuated *** review focuses on the EMI shielding composites with 1D metallic,magnetic,and dielectric nanofillers,which could be constructed in the final form of membrane-or aerogel/sponge-like shielding *** to the structural features,1D metallic,magnetic,and dielectric nanofillers are classified into nanowires,nanorods,nanospindles,nanochains,nanofibers,nanotubes,nanorings,nanocoils,and quasi-one-dimensional(1D)van der Waals ***,the fabricated routes,shielding performances,and EM waves attenuation mechanism of the 1D metallic,magnetic,and dielectric nanofiller-based composites are *** is found that the dominant shielding mechanism of most of the 1D metal-based EMI composites is reflection loss,while that of 1D magnetic and dielectric nanomaterials-based EMI composites is absorption loss caused by interfacial polarization,natural resonance,eddy current,and multiple ***,the challenges and prospects of 1D nanofiller-based composites with a tunable architecture and composition are put forward,aiming to give a guideline for the next generation of high-performance EMI shielding materials.

关键词： one-dimensional nanofillers composites electromagnetic interference(EMI)shielding mechanism

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Joint channel selection and power control for video streaming over D2D communications based cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2018年第1期25卷 1-14页

作者： Gao Ya Zhang Hailin lu xiaofeng State Key Laboratory of Integrated Services Networks Xidian University College of Physics and Electronic Information Luoyang Normal University

A joint channel selection and power control scheme is developed for video streaming in device-to-device （D2D） communications based cognitive radio networks. In particular, physical queue and virtual queue models by applying ＇M/G/1 queue＇ and ＇M/G/1 queue with vacations＇ theories are built up, respectively, to evaluate the delays experienced by various video traffics. Such delays play a vital role in calculating the packet loss rate for video streaming, which reflects the video distortion. Based on the distortion model, a video distortion minimization problem is formulated, subject to the rate constraint, maximum power constraint, primary users＇ tolerant interference constraint, and secondary users＇ minimum data rate requirement constraint. The optimization problem turns out to be a mixed integer nonlinear programming （MINLP） , which is generally nondeterministic in polynomial time. A Lagrangian dual method is thus employed to reformulate the video distortion minimization problem, based on which the sub-gradient algorithm is used to determine a relaxed solution. Thereafter, applying the iterative user removal yields the optimal joint channel selection and power control solution to the original MINLP problem. Extensive simulations validate our proposed scheme and demonstrate that it significantly increases the peak signal- to-noise ratio （PSNR） compared with the existing schemes.

关键词： channel selection power control cognitive radio networks D2D communications video streaming convex optimization

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Simultaneous wireless information and power transfer with fixed and adaptive modulation

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Digital Communications and Networks 2022年第3期8卷 303-313页

作者： Jie Hu Guangming Liang Qin Yu Kun Yang xiaofeng lu Yangtze Delta Region Institute(Huzhou)&School of Information and Communication Engineering University of Electronic Science and Technology of ChinaHuzhou313001China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu611731China State Key Laboratory of Integrated Services Networks Xidian UniversityXi'an710071China

Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network. However, Simultaneous Wireless Information and Power Transfer (SWIPT) in the same RF bands is challenging. The majority of previous studies compared SWIPT performance to Gaussian signaling with an infinite alphabet, which is impossible to implement in any realistic communication system. In contrast, we study the SWIPT system in a well-known Nakagami-m wireless fading channel using practical modulation techniques with finite alphabet. The attainable rate-energy-reliability tradeoff and the corresponding rationale are revealed for fixed modulation schemes. Furthermore, an adaptive modulation-based transceiver is provided for further expanding the attainable rate-energy-reliability region based on various SWIPT performances of different modulation schemes. The modulation switching thresholds and transmit power allocation at the SWIPT transmitter and the power splitting ratios at the SWIPT receiver are jointly optimized to maximize the attainable spectrum efficiency of wireless information transfer while satisfying the WPT requirement and the instantaneous and average BER constraints. Numerical results demonstrate the SWIPT performance of various fixed modulation schemes in different fading conditions. The advantage of the adaptive modulation-based SWIPT transceiver is validated.

关键词： Simultaneous wireless information and power transfer(SWIPT) Fixed/adaptive modulation Rate-energy-reliability trade-off Transceiver design Energy self-sustainability

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Elucidating the Uptake and Distribution of Nanoparticles in Solid Tumors via a Multilayered Cell Culture Model

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Nano-Micro Letters 2015年第2期7卷 127-137页

作者： Darren Yohan Charmainne Cruje xiaofeng lu Devika Chithrani Department of Physics Ryerson University Keenan Research Centre Li Ka Shing Knowledge Institute St. Michael’s Hospital

Multicellular layers(MCLs) have previously been used to determine the pharmacokinetics of a variety of different cancer drugs including paclitaxel, doxorubicin, methotrexate, and 5-fluorouracil across a number of cell lines. It is not known how nanoparticles(NPs) navigate through the tumor microenvironment once they leave the tumor blood *** this study, we used the MCL model to study the uptake and penetration dynamics of NPs. Gold nanoparticles(GNPs)were used as a model system to map the NP distribution within tissue-like structures. Our results show that NP uptake and transport are dependent on the tumor cell type. MDA-MB-231 tissue showed deeper penetration of GNPs as compared to MCF-7 one. Intracellular and extracellular distributions of NPs were mapped using Cyto Viva imaging. The ability of MCLs to mimic tumor tissue characteristics makes them a useful tool in assessing the efficacy of particle distribution in solid tumors.

关键词： Gold nanoparticles Tumor Multicellular cell layers Tissue

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Experimental investigation of a counter-rotating compressor with boundary layer suction

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Chinese Journal of Aeronautics 2015年第4期28卷 1044-1054页

作者： Shi Lei Liu Bo Na Zhenzhe Wu Xiaoxiong lu xiaofeng School of Power and Energy Northwestern Polytechnical University

This paper presents the aspirated modification of a dual-stage counter-rotating compressor which contains inlet guide vanes（IGVs）, two counter-rotating rotors（R1, R2）, and outlet guide vanes（OGVs）.Uniform circular holes are circumferentially distributed over the rotors＇ tips on the shroud casing which are designed to remove the low-energy fluid near the shroud *** are hollow blades with two slots designed on the suction side which can better control the flow on the suction surface through boundary layer *** works about the experiments have been carried out since June 2012 and the effect of flow suction on the performance of the compressor is investigated in *** lines at a 70% corrected rotating speed are tested and those with higher rotating speeds will be studied in the near *** results indicate that boundary layer suction can improve the compressor characteristics and the best suction methodology varies along the operating *** the near stall condition, suction from the R2 tip region can obviously increase the efficiency and the total pressure ratio, as well as improve the flow *** efficiency can be maximally increased by 4.24% with an increase of 1.94% in massflow under a suction flow of 160 m3/*** at the R1 position with a suction rate below 0.35% in a high flow situation can make the performance of the compressor better than *** the peak efficiency point, boundary layer suction from the slots of OGVs is the best choice in improving the efficiency, but it causes a 0.1% loss in the total pressure ratio.

关键词： Boundary layer suction Compressor characteristicCounter-rotatingcompressor Hollow blade Shroud casing

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Joint user grouping and resource allocation for uplink virtual MIMO systems

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Science China(Information Sciences) 2016年第2期59卷 60-73页

作者： xiaofeng lu Kun YANG Wenna LI Shaojun QIU Hailin ZHANG State Key Laboratory of Integrated Service Networks Xidian University School of Computer Science and Electrical Engineering University of Essex

MIMO has become a core technology of 5G network to largely improve system throughput. Due to the cost and size of the user equipment(UE), the application of MIMO uplink is limited by the difficulty in practical implementation at the user side. Virtual MIMO has been widely investigated to solve this problem for wireless uplink systems. However, virtual MIMO transmission leads to performance degradation due to the multiuser interference. To obtain good trade-off between the system throughput and transmission performance,we investigate joint user grouping and resource allocation under the consideration of system throughput and average mean squared error(MSE) performance in SC-FDMA uplink systems. Based on linear MIMO detection,we first develop MSE-oriented user grouping criteria for evaluation of transmission performance, then establish dynamic user grouping and optimal resource allocation problems for hard and elastic average MSE *** proposed joint resource allocation algorithm is evaluated in SC-FDMA uplink scenarios and the results show that it achieves maximum system throughput with average MSE guaranteed for the hard MSE constraint algorithms and the alterable trade-off between system throughput and average MSE for the elastic MSE constraint algorithms.

关键词： virtual MIMO user grouping average MSE system throughput resource allocation

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Electronic modulation and interface engineering of electrospun nanomaterials‐based electrocatalysts toward water splitting

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Carbon Energy 2021年第1期3卷 101-128页

作者： Wei Song Meixuan Li Ce Wang xiaofeng lu State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchunPeople's Republic of China Alan G.MacDiarmid Institute College of ChemistryJilin UniversityChangchunPeople's Republic of China

Nowdays,electrocatalytic water splitting has been regarded as one of the most efficient means to approach the urgent energy crisis and environmental ***,to speed up the electrocatalytic conversion efficiency of their half reactions including hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),electrocatalysts are usually essential to reduce their kinetic energy *** nanomaterials possess a unique one‐dimensional structure for outstanding electron and mass transportation,large specific surface area,and the possibilities of flexibility with the porous feature,which are good candidates as efficient electrocatalysts for water *** this review,we focus on the recent research progress on the electrospun nanomaterials‐based electrocatalysts for HER,OER,and overall water splitting ***,the insights of the influence of the electronic modulation and interface engineering of these electrocatalysts on their electrocatalytic activities will be deeply discussed and ***,the challenges and development opportunities of the electrospun nanomaterials‐based electrocatalysts for water splitting are *** on the achievements of the significantly enhanced performance from the electronic modulation and interface engineering of these electrocatalysts,full utilization of these materials for practical energy conversion is anticipated.

关键词： electrocatalysis electronic modulation electrospun nanomaterials interface engineering water splitting

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Size-Dependent Gold Nanoparticle Interaction at Nano–Micro Interface Using Both Monolayer and Multilayer(Tissue-Like) Cell Models

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Nano-Micro Letters 2016年第1期8卷 44-53页

作者： Darren Yohan Charmainne Cruje xiaofeng lu Devika B.Chithrani Department of Physics Ryerson University Keenan Research Centre Li Ka Shing Knowledge InstituteSt. Michael’s Hospital

Gold nanoparticles(GNPs) are emerging as a novel tool to improve existing cancer therapeutics. GNPs are being used as radiation dose enhancers in radiation therapy as well as anticancer drugs carriers in chemotherapy. However,the success of GNP-based therapeutics depends on their ability to penetrate tumor tissue. GNPs of 20 and 50 nm diameters were used to elucidate the effects of size on the GNP interaction with tumor cells at monolayer and multilayer level. At monolayer cell level, smaller NPs had a lower uptake compared to larger NPs at monolayer cell level. However, the order was reversed at tissue-like multilayer level. The smaller NPs penetrated better compared to larger NPs in tissue-like *** on our study using tissue-like materials, we can predict that the smaller NPs are better for future therapeutics due to their greater penetration in tumor tissue once leaving the leaky blood vessels. In this study, tissue-like multilayer cellular structures(MLCs) were grown to model the post-vascular tumor environment. The MLCs exhibited a much more extensive extracellular matrix than monolayer cell cultures. The MLC model can be used to optimize the nano–micro interface at tissue level before moving into animal models. This would accelerate the use of NPs in future cancer therapeutics.

关键词： Gold nanoparticles Multilayer cellular structures Tissue penetration Hyper spectral imaging Size dependence

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General synthesis of Pt and Ni co-doped porous carbon nanofibers to boost HER performance in both acidic and alkaline solutions

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Chinese Chemical Letters 2023年第2期34卷 263-267页

作者： Jiaqi Xu Mengxiao Zhong Na Song Ce Wang xiaofeng lu Alan G.MacDiarmid Institute College of ChemistryJilin UniversityChangchun 130012China

It is essential to develop efficient electrocatalysts to generate hydrogen from water electrolysis for hydrogen economy. In this work, platinum(Pt) and nickel(Ni) co-doped porous carbon nanofibers(Pt/NiPCNFs) with low Pt content were prepared via an electrospinning, carbonization and galvanic replacement reaction. Because of the high electrical conductivity, abundant electrochemical active sites and synergistic effect between Pt and Ni nanoparticles, the optimized Pt/Ni-PCNFs catalyst shows an excellent HER activity with overpotentials of 20 m V in 0.5 mol/L H_(2)SO_(4) and 46 m V in 1 mol/L KOH at a current density of10 m A/cm^(2). Furthermore, over 35-h long-term stability has been achieved without significant *** work provides a simple route to prepare highly efficient electrocatalysts for water splitting and has great prospects in the field of renewable energy.

关键词： Electrospinning Platinum Nickel Porous carbon nanofibers Hydrogen evolution reaction

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Building up 1-D, 2-D, and 3-D Polyiodide Frameworks by Finely Tuning the Size of Aryls on Ar-S-TTF in the Charge-Transfer （CT） Complexes of Ar-S-TTFs and Iodine

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Chinese Journal of Chemistry 2018年第9期36卷 845-850页

作者： Longfei Ma Haili Peng xiaofeng lu Lei Liu Xiangfeng Shao State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China

The arylthio-substituted tetrathiafuivalenes （Ar-S-TTFs） are electron donors having three reversible states, neutral, cation radical, and dica- tion. The charge-transfer （CT） between Ar-S-TTFs （TTF1--TTF3） and iodine （12） is reported herein. TTF1--TTF3 show the CT with 12 in the CH2C12 solution, but they are not completely converted into cation radical state. In CT complexes of TTF1--TTF3 with 12, the charged states of Ar-S-TTFs are distinct from those in solution. TTF1 is at cation radical state, and TTF2--TTF3 are oxidized to dication. The iodine components in complexes show various structures including 1-D chain of V-shaped （Is）-, and 2-D and 3-D iodine networks composed of 12 and （13）^- .

关键词： polyiodide tetrathiafulvalene charge-transfer complex crystal engineering halogen bond

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