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Continuous Separation of Multiple Size Microparticles using Alternating Current Dielectrophoresis in Microfluidic Device with Acupuncture Needle Electrodes

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Chinese Journal of Mechanical engineering 2016年第2期29卷 325-331页

作者： TAO Ye REN Yukun YAN Hui JIANG Hongyuan School of Mechatronics Engineering Harbin Institute of Technology State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The need to continuously separate multiple microparticles is required for the recent development of lab-on-chip technology. Dielectrophoresis（DEP）-based separation device is extensively used in kinds of microfluidic applications. However, such conventional DEP-based device is relatively complicated and difficult for fabrication. A concise microfluidic device is presented for effective continuous separation of multiple size particle mixtures. A pair of acupuncture needle electrodes are creatively employed and embedded in a PDMS（poly-dimethylsiloxane） hurdle for generating non-uniform electric field thereby achieving a continuous DEP separation. The separation mechanism is that the incoming particle samples with different sizes experience different negative DEP（n DEP） forces and then they can be transported into different downstream outlets. The DEP characterizations of particles are calculated, and their trajectories are numerically predicted by considering the combined action of the incoming laminar flow and the n DEP force field for guiding the separation experiments. The device performance is verified by successfully separating a three-sized particle mixture, including polystyrene microspheres with diameters of 3 μm, 10 μm and 25 μm. The separation purity is below 70% when the flow rate ratio is less than 3.5 or more than 5.1, while the separation purity can be up to more than 90% when the flow rate ratio is between 3.5 and 5.1 and meanwhile ensure the voltage output falls in between 120 V and 150 V. Such simple DEP-based separation device has extensive applications in future microfluidic systems.

关键词： continuous separation of multiple size particles dielectrophoresis acupuncture needle electrodes microfluidic

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Size-resolved carbonaceous components and water-soluble ions measurements of ambient aerosol in beijing

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Journal of Environmental Sciences 2017年第4期29卷 298-313页

作者： Pusheng Zhao Yina Chen Jie Su Institute of Urban Meteorology China Meteorological Administration Environmental Meteorology Forecasting Center of Beijing-Tianjin-Hebei State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai University

A MOUDI-120 sampler was used in beijing to collect multi-stage samples in the summer and winter of 2013 to 2015. Thirty-three sample sets were collected during the daytime,nighttime, and different pollution levels. The actual relative humidity in the impactors was calculated for the first time. The carbonaceous components（organic and elemental carbon,OC and EC, respectively） and water-soluble inorganic ions（Na~＋, NH4~＋, K~＋, Mg^（2＋）, Ca^（2＋）, Cl^-, NO3^-,and SO4^（2-）） were analyzed in each sample. The characteristics of the mass concentration distribution and charge balance were discussed. On the basis of relative humidity in the impactors, aerosols less than 1.0 μm were sampled under relatively dry conditions in most cases. The concentration levels for the chemical species were higher in the winter than in the summer. Three modes（condensation mode, droplet mode, and coarse mode） could be identified from the distributions of NH4~＋, NO3^-, SO4^（2-）, Cl^-, K~＋, OC and EC. The distribution characteristics for the pollution dissipation process were different from the pollution accumulation process. NO3^-and NO2^-contributed most of the negative electric charges in the stage below 0.1 μm. In the condensation mode, the cations were dominated by NH4~＋, which was sufficient to balance the anions. In the droplet mode of the heavily polluted samples,the ammonium was not sufficient to balance the anions. In the coarse mode, the positive electric charges were primarily composed of metal cations. The analyzed anions were not sufficient to neutralize the measured cations.

关键词： Size-resolved Carbonaceous Ion Aerosol

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Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in colortunable organic electroluminescent devices

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Light(Science & Applications) 2018年第1期7卷 629-640页

作者： Junwei Xu Yue Cui Gregory M.Smith Peiyun Li Chaochao Dun Linqi Shao Yang Guo Hongzhi Wang Yonghua Chen David L.Carroll Center for Nanotechnology and Molecular Materials Wake Forest UniversityWinston-SalemNC 27109USA Department of Physics Wake Forest UniversityWinston-SalemNC 27106USA Key Laboratory of Luminescence and Optical Information(Ministry of Education) Institute of Optoelectronics TechnologyBeijing Jiaotong University100044 BeijingP.R.China Department of Electro-Optics School of EngineeringUniversity of DaytonDaytonOH 45469USA Department of Mathematics Wake Forest UniversityWinston-SalemNC 27106USA State Key Laboratory for Modification of Chemical Fibers and Polymer Materials 201620 ShanghaiP.R.China College of Materials Science and Engineering Donghua University201620 Shanghai P.R.China Institute of Advanced Materials Nanjing Tech University211816 NanjingJiangsuP.R.China Department of Physics and Astronomy College of CharlestonCharlestonSC 29424USA

In this work,we show that the spin dynamics of excitons can be dramatically altered by Maxwell magnetic field coupling,together with an ion-enhanced,low-internal-splitting-energy organic semiconducting *** employing a unique,alternating current(AC)-driven organic electroluminescent(OEL)device architecture that optimizes this magnetic field coupling,almost complete control over the singlet-to-triplet ratio(from fluorescent to phosphorescent emission in a single device)is *** attribute this spin population control to magnetically sensitive polaron–spin pair intersystem crossings(ISCs)that can be directly manipulated through external driving *** an illustration of the utility of this approach to spin-tailoring,we demonstrate a simple hybrid(double-layer)fluorescence–phosphorescence(F–P)device using a polyfluorene-based emitter with a strong external Zeeman effect and ion-induced long carrier *** control over de-excitation pathways is achieved by controlling the device-driving frequency,resulting in complete emission blue–red color *** photoluminescence(PL)spectroscopy directly confirms that this color control derives from the magnetic manipulation of the singlet-totriplet *** results may pave the way to far more exotic organic devices with magnetic-field-coupled organic systems that are poised to usher in an era of dynamic spintronics at room temperature.

关键词： temperature. coupling Maxwell

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Responses of Soil Enzyme Activities and Microbial Community Composition to Moisture Regimes in Paddy Soils Under Long-Term Fertilization Practices

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Pedosphere 2018年第2期28卷 323-331页

作者： LI Weitao WU Meng LIU Ming JIANG Chunyu CHEN Xiaofen Yakov KUZYAKOV Jorg RINKLEBE LI Zhongpei State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049 (China) Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil Science University of Gottingen 37073Gottingen (Germany) Institute of Environmental Sciences Kazan Federal University 420049 Kazan (Russia) Agro-Technology Institute RUDN University 117198 Moscow (Russia) University of Wuppertal School of Architecture and Civil Engineering Institute of Foundation Engineering Water- and Waste- Management Soil- and Groundwater-Management Pauluskirchstrafle 7 42285t Wuppertal (Germany) Department of Environment and Energy Sejong University Seoul 05006 (Korea)

The effects of fertilization on activity and composition of soil microbial community depend on nutrient and water availability;however,the combination of these factors on the response of microorganisms was seldom *** study investigated the responses of soil microbial community and enzyme activities to changes in moisture along a gradient of soil fertility formed within a long-term(24 years)field ***(0–20 cm)were sampled from the plots under four fertilizer treatments:i)unfertilized control(CK),ii)organic manure(M),iii)nitrogen,phosphorus,and potassium fertilizers(NPK),and iv)NPK plus M(NPK+M).The soils were incubated at three moisture levels:constant submergence,five submerging-draining cycles(S-D cycles),and constant moisture content at 40%water-holding capacity(low moisture).Compared with CK,fertilization increased soil organic carbon(SOC) by 30.1%–36.3%,total N by 27.3%–38.4%,available N by 35.9%–56.4%,available P by 61.4%–440.9%,and total P by 28.6%–102.9%.Soil fertility buffered the negative effects of moisture on enzyme activities and microbial community *** activities decreased in response to submergence and S-D cycles versus low *** with low moisture,S-D cycles increased total phospholipid fatty acids(PLFAs)and actinomycete,fungal,and bacterial *** increased level of PLFAs in the unfertilized soil after five S-D cycles was greater than that in the fertilized *** in soil microbial properties responding to moisture separated CK from the long-term fertilization *** coefficients of variation of microbial properties were negatively correlated with SOC,total P,and available *** with higher fertility maintained the original microbial properties more stable in response to changes in moisture compared to low-fertility soil.

关键词： microbial property phospholipid fatty acids soil fertility submergence submerging-draining cycle

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Research on Information Structure of Programmatic Advertising Markets

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IFAC-PapersOnLine 2017年第1期50卷 13587-13592页

作者： Li, Juanjuan Yuan, Yong Zhao, Xueliang Wang, Fei-Yue The State Key Laboratory of Management Control for Complex Systems Institute of Automation Chinese Academy of Sciences Qingdao Academy of Intelligent Industries Beijing Engineering Research Center of Intelligent Systems and Technology Beijing Qingdao China Research Center of Military Computational Experiments and Parallel Systems National University of Defense Technology Changsha China

With the abundance of online big data and computing resources, as well as the rapid develop-ment and diversification of business models, programmatic advertising (PA) has emerged and become the mainstream and one of the most promising advertising channels in recent years. As an effective way to precision marketing, PA relies heavily on the information elicited from analyzing Web users and pages, which can help advertisers precisely identify their best-matched audiences and evaluate the ad impressions in a real-time fashion In PA markets, publishers serve as the supplier of ad impressions, and have control on whether, what and how to reveal such key information to advertisers. These decisions play a central role in the information structure of data-driven PA markets, and attract intensive research interests. In this paper, we strive to investigate publishers’ rational preference over the symmetric and asymmetric information structures, with the aim of maximizing their revenues. Our model views publishers’ revenue as a function of the information structure among advertisers, and we hereby proved its convexity under an incentive compatible mechanism. This conclusion indicates that publishers prefer an asymmetric information structure rather than a symmetric one. Our research findings can help improve publishers’ revenue, and also can explain the underlying rationale for the hybrid PA markets mixed by public real-time bidding and private marketplaces. © 2017

关键词： Commerce Big data Marketing Advertising markets Asymmetric information Computing resource Incentive compatible mechanisms Information structures Precision marketings private marketplace Real time biddings

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Hydrodeoxygenation and hydroisomerization of palmitic acid over bi-functional Co/H-ZSM-22 catalysts

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Fuel Processing technology 2018年 172卷 29-35页

作者： Yaya Cao Yanchun Shi Yunfei Bi Kejing Wu Shaojian Hu Yulong Wu Shaobin Huang College of Environment and Energy South China University of Technology Guangzhou 510006 PR China Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 PR China Laboratory of Hydrogenation Research Institute of Petroleum Processing Sinopec Beijing 100083 China Beijing Engineering Research Center for Biofuels Beijing 100084 PR China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control Guangzhou 510006 PR China

Hydrodeoxygenation and hydroisomerization of palmitic acid were achieved over bi-functional Co/H-ZSM-22 catalysts (about 4 wt% Co loading), and the maximum of isoproducts reached up to 73.4% selectivity at 260 °C for 4 h in presence of 2 MPa H 2 . Compared to parent H-ZSM-22, the impregnation of Co species for bi-functional catalysts could catalyze completely palmitic acid conversion into 100% selectivity of alkanes in spite of low pressure (1 MPa H 2 ). Furthermore, bi-functional Co/H-ZSM-22 catalysts tailored the deoxygenation route via hydrodeoxygenation leading to more C 16 formation. With decreasing of reaction pressure, mole ratio of C 16 /C 15 decreased during complete conversion of palmitic acid, indicating that low reaction pressure favored hydrodecarbonylation to produce more C 15 . Bi-functional Co/H-ZSM-22 catalysts also exhibited great stability after five runs without any deactivation.

关键词： Hydrodeoxygenation Hydroisomerization Palmitic acid Co/H-ZSM-22

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First observation of Pt3Si phase at Ni0.86Pt0.14 and Si Silicide Reactions

First observation of Pt3Si phase at Ni0.86Pt0.14 and Si Sili...

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International Conference on Solid-state and Integrated Circuit technology

作者： Qingzhu Zhang Hailing Tu Huaxiang Yin Feng Wei Hongbin Zhao Zhaohao Zhang Jianfeng Gao Qianhui Wei Xiao Zhang Zhangyu Zhou Yanyan Fan Jiang Yan State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous Metals Beijing China University of Chinese Academy of Sciences Beijing China Key Laboratory of Microelectronics Devices & Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing China College of Electronic and Information Engineering North China University of Technology Beijing China

In this paper, the relationship of Ni 0.86 Pt 0.14 -silicide film properties and the corresponding phase evolution is investigated extensively. We find that the Ni(Pt)-silicide phase transformation is often accompanied with greatly sheet resistance (R sh ) changes. However, Pt 3 Si peaks are detected when the R sh of Ni(Pt)-silicide starts to change from low resistance to high resistance. The Pt 3 Si phases maybe the transient phases, at a drastic Ni(Pt)-silicide phase transformation and crystal structure changes. The new Pt 3 Si phases would be transformed into a crystal structure similar to the new generating Ni x Si 1-x phase, which contribute to form a more stable and reliable Ni(Pt)-silicide film. A new model is proposed to interpret the new generated Pt 3 Si phase. The discovery contributes to a better understanding the role of Pt and control Ni(Pt)-silicide formation in future advanced devices.

关键词： Silicides Nickel alloys Annealing Silicon Resistance X-ray scattering

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High energy and high brightness laser compton backscattering gamma-ray source at IHEP

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Matter and Radiation at Extremes 2018年第4期3卷 219-226页

作者： Guang-Peng An Yun-Long Chi Yong-Le Dang Guang-Yong Fu Bing Guo Yong-Sheng Huang Chuang-Ye He Xiang-Cheng Kong Xiao-Fei Lan Jia-Cai Li Fu-Long Liu Jin-Shui Shi Xian-Jing Sun Yi Wang Jian-Li Wang Lin Wang Yuan-Yuan Wei Gang Wu Guang-Lei Xu Xiao-Feng Xi Guo-Jun Yang Chun-Lei Zhang Zhuo Zhang Zhi-Peng Zheng Xiao-Ding Zhang Shao-Ping Zhang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsCASBeijing 100049China China Institute of Atomic Energy Beijing 102413China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621999China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China Physics and Space Science College China West Normal UniversityNanchong 637009China

Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS)gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful researchplatform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantumelectrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO_(2) laser system are employed. All the triggersignals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure thetemporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to alignthe electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, thephoton-nuclear physics, nuclear astrophysics and some basic QED phenomena.

关键词： laser compton scattering Calibration Photon-nuclear physics Gamma-gamma collider Nuclear astrophysics QED Gamma-gamma scattering Detection

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Improving Auction Mechanisms for Online Real-Time Bidding Advertising with a Two-stage Resale Model

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IFAC-PapersOnLine 2017年第1期50卷 13575-13580页

作者： Qin, Rui Yuan, Yong Wang, Fei-Yue The State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China Qingdao Academy of Intelligent Industries Qingdao China Research Center of Military Computational Experiments and Parallel System National University of Defense Technology Changsha China Beijing Engineering Research Center of Intelligent Systems and Technology Institute of Automation Chinese Academy of Sciences Beijing China

Real Time Bidding (RTB), widely publicized as one of the most promising big-data-driven business models for online computational advertising, has the potential of effectively monetizing user clicks and impressions via two-stage auctions with resale. Demand side platforms (DSPs) play a key role as intermediators in this auction process. Typically, the first-stage auctions will be conducted separately in each DSP to determine one winning advertiser registered on it, and in the second-stage auction, each DSP submits a bid based on its winning advertiser's bid to the ad exchange platform (AdX). The highest-bid DSP wins the ad impression from AdX and resells it to its winning advertiser in pursuit of the intermediate fee. This two-stage resale auction is a critical component in maintaining the effectiveness and efficiency of RTB ecosystems. In this paper, we strive to identify and design potential improvements for this auction mechanism with the aim of enhancing the total revenue of both advertisers and DSPs. We also validated our proposed auction mechanisms using the computational experiment approach. The experimental results indicate that our proposed mechanisms can make both advertisers and DSPs better off. Our work represents the first step towards a new research area of optimal mechanism design for RTB auctions, and is expected to provide useful managerial insights in RTB market practice. © 2017

关键词： Sales Commerce Machine design Auction mechanisms Computational advertisings Computational experiment Critical component Demand side Effectiveness and efficiencies Optimal mechanism designs Real time

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Local articulation points in complex networks

arXiv

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arXiv 2018年

作者： Yu, Senbin Gao, Liang Song, Rongqiu Institute of Transportation Systems Science and Engineering MOE Key Laboratory of Urban Transportation System Theory and Technology State Key Laboratory of Rail Traffic Control and Safety Center of Cooperative Innovation for Beijing Metropolitan Transportation Beijing Jiaotong University Beijing100044 China Yinchuan Municipal Bureau of Big Data Management and Service Yinchuan750011 China

An articulation point (AP) is any node whose removal increases the number of connected components of a graph. There is no doubt that this kind of node which occupies a non-ignorable fraction of real-world networks plays a key role in ensuring the connectivity. However, we should not thus neglect the impacts of non-APs nodes. In this paper, we define a local AP (LAP) whose removal will increase the number of connected components within its r-step neighborhood. Through investigating the fraction of LAPs in forty-five real networks, we find a critical proportion Scr, which is equal to 0.5 (S = r/D, D is the diameter of a network), and this result can also be turned out in ER networks. In addition, we present a unique advantage of LAPs in dismantling networks under the process of targeted attack, compared with APs, which provide another way of thinking to improve the calculation efficiency of APs and design better targeted attack strategy of network *** Codes Game theory, economics, social and behavioral sciences Copyright © 2018, The Authors. All rights reserved.

关键词： Complex networks

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