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The Hemodynamic Comparative study Between Pulsatile and Non-Pulsatile VA ECMO:A Primary Numerical study

Computer Modeling in Engineering & sciences 2018年第8期116卷 247-262页

作者： Qi Zhang Bin Gao yue shi Chang yu school of Life science and BioEngineering Beijing University of TechnologyBeijing100124China.

Although pulsatile ECMO,as novel kinds of ECMO,has been attracted more and more attention,the differences of the hemodynamic effects of the pulsatile ECMO on the aorta,the cerebral perfusion,and left ventricular work were still *** aim of this study was to clarify the hemodynamic differences of the cardiovascular system between the pulsatile and non-pulsatile VA *** this study,three ECMO support modes,named as“constant flow mode”,“co-pulse mode”and“counter pulse mode”,were *** computational fluid dynamics(CFD)study was carried *** distribution of the oxygenated blood,the blood velocity vector,the oscillatory shear index(OsI),the relative residence time(RRT),the left ventricular external work(EW),the equivalent left ventricular afterload(EAL)and the energy loss of cardiovascular system(EL)were calculated to compare the hemodynamic *** simulation results demonstrate that the oxygenated blood under co-pulse mode was easier to perfuse into the three braches vessels than that under both other *** addition,the ECMO under counter pulse mode could also achieve lowest RRT(constant flow mode 220 ***-pulse mode 132 *** pulse mode 93).similarly,the ECMO under counter pulse mode could significantly reduce the left ventricular external work(co-pulse mode 1.51 w *** flow mode 1.44 w and counter pulse mode 1.30 w),left ventricular afterload(constant flow mode 1.03 mmHg·s/ml ***-pulse mode 1.67 mmHg·s/ml *** pulse mode 0.82 mmHg·s/ml)and energy loss of arterial system(constant flow mode 0.18 w ***-pulse mode 0.50 w *** pulse mode 0.16 w).In short,the ECMO under counter pulse mode could have advantages to the left ventricular *** contrast,the ECMO under co-pulse mode has more benefit to cerebral oxygen perfusion.

关键词： pulsatile non-pulsatile VA ECMO hemodynamics CFD

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Accuracy assessment of global historical cropland datasets based on regional reconstructed historical data——A case study in Northeast China

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science China Earth sciences 2010年第11期53卷 1689-1699页

作者： Li BeiBei Fang XiuQi Ye yu Zhang XueZhen Beijing Normal Univ Sch Geog Beijing 100875 Peoples R China Chinese Acad sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

Historical cropland datasets are fundamental for quantifying the effects of human land use activities on climatic change and the carbon cycle. Two representative global land-use datasets, the Global Land Use Database (termed sAGE dataset) and the Historical Database of the Global Environment (termed HYDE dataset) have been established and used widely. Despite improvement of data quality and methodologies for extracting historical land use information, certain dataset limitations exist that need to be quantified and communicated to users so that they can make informed decisions on whether and how these land-use products should be used. The Cropland data of Northeast China (CNEC) is based on calibrated historical data and a multi-sourced data conversion model, and reconstructs cropland cover change in Northeast China over the last 300 years. Us- ing the CNEC as a reference, we evaluated the accuracy of cropland cover for sAGE and HYDE in Northeast China at spatial scales ranging from the entire Northeast China to provinces and even individual raster grid cells. Neither sAGE nor HYDE reflects real historical land reclamation. Cropland areas in sAGE are overestimated by 20.98 times in 1700 to 1.6 times in 1990. Although HYDE is better, there are significant disagreements in cropland area and distribution between HYDE and CNEC, especially in the 18th and 19th centuries. The proportion of total grid cells whose relative error was greater than 100% was 63.55% in 1700 and 53.27% in 1780. Global cropland dataset errors over Northeast China originate mainly from both the reverse calculation method for historical cropland data based on modern spatial patterns, and modern land-use outputs from satellite data.

关键词： LUCC dataset accuracy assessment Northeast China

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Effect of triple-phase contact line on contact angle hysteresis

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science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1045-1050页

作者： yu Yang WU Qun ZHANG Kai JI BaoHua Biomechanics and Biomaterials Laboratory Department of Applied Mechanics School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Department of Engineering Mechanics Tsinghua University Beijing 100084 China

Recent studies have shown that the triple-phase contact line has critical effect on the contact angle hysteresis of *** this study,patterned surfaces with various surface structures of different area fractions were prepared by electron etching on a silicon *** advancing angle,receding angle and hysteresis angle of these surfaces were *** experimental results showed that while the geometry of microstructure and contact line have a minor effect on the advancing angle,they have a significant effect on the receding angle and thus the hysteresis *** have shown that the effect of microstructure and the contact line can be described by a quantitative parameter termed the triple-phase line *** theoretical predictions were in good agreement with our experimental results.

关键词： contact angle hysteresis receding angle surface microstructure area fraction contact line ratio wetting

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Observational Facts Regarding the Joint Activities of the southwest Vortex and Plateau Vortex after Its Departure from the Tibetan Plateau

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Advances in Atmospheric sciences 2016年第1期33卷 34-46页

作者： shuhua yu Wenliang GAO Dixiang XIAO Jun PENG Institute of Plateau Meteorology China Meteorological AdministrationChengdu 610072 Ya'an Meteorological Bureau Ya'an 625000 sichuan Meteorological Observatory Chengdu 610072

Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM（Tropical Rainfall Measuring Mission） data,as well as annual statistics for the plateau vortex and shear line,the joint activity features of sustained departure plateau vortexes（sDPVs） and southwest vortexes（sWVs） are *** new and useful observational facts and understanding are obtained about the joint activities of the two types of *** results show that：（1） The joint active period of the two vortexes is from May to August,and mostly in June and July.（2） The sDPVs of the partnership mainly originate near Zaduo,while the sWVs come from Jiulong.（3） Most of the two vortexes move in almost the same direction,moving eastward together with the low *** sDPVs mainly act in the area to the north of the Yangtze River,while the sWVs are situated across the Yangtze River valley.（4） The joint activity of the two vortexes often produces sustained regional heavy rainfall to the south of the Yellow River,influencing wide areas of China,and even as far as the Korean Peninsula,Japan and Vietnam.（5） Most of the two vortexes are baroclinic or cold vortexes,and they both become strengthened in terms of their joint activity.（6） When the two vortexes move over the sea,their central pressure descends and their rainfall increases,especially for sWVs.（7） The two vortexes might spin over the same area simultaneously when there are tropical cyclones in the eastern and southern seas of China,or move southward together if a tropical cyclone appears near Hainan Island.

关键词： plateau vortex southwest vortex observational study

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Effective Removal of Tetracycline by Using Biochar supported Fe3O4 as a UV-Fenton Catalyst

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Chemical Research in Chinese Universities 2019年第1期35卷 79-84页

作者： yu Xiaodan LIN Xinchen LI Weiguang FENG Wei school of Environment Harbin Institute of TechnologyHarbin 150090P.R.China Key Labroratory of songliao Aquatic Environnmento Ministry of Education Jilin Jianzhu UniversityChangchun 130118P.R.China Key Laboratory of Groundwater Resource and Environment Ministry Education College of Environment and ResourcesJilin UniversityChangehun 130021P.R.China state Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090.P.R.China

Novel Fe3O4-decorate hierarchical porous carbon skeleton derived from maize straw(Fe3O4@MsC)was synthesized by a facile co-precipitation process and a calcination process,which was developed as a UV assisted heterogeneous Fenton-like *** as-synthesized catalysts were characterized via X-ray powder diffraction(XRD), scanning electron microscope(sEM),transmission electron microscope(TEM),Brunauer-Emmet-Teller(BET)and vibrating sample magnetometer(VsM)at room *** morphology and structure analysis revealed that the as-prepared Fe3O4@MsC retained the original pore morphology of the maize straw *** non-uniform poly- hedral Fe3O4 grew on the whole surface of the MsC,which reduced the aggragation of Fe3O4 and provided more active sites to strengthen the UV-assisted Fenton-like *** a result,the tetracycline(TC)degradation efficiency after 40 min reaction and total organic carbon(TOC)removal efficiency after 2 h reaction of Fe3O4@MsC catalyzing UV-Fenton system reached 99.2%and 72.1%,respectively,which were more substantial than those of Fe3O4@MsC/H2O2(31.5%and 2%),UV/H2O2 system(68%and 23.4%)and UV/Fe3O4/H2O2(80% and 37.5%).The electron spin resonance(EsR)results showed that the ·OH played an important role in the catalytic reaction.A possible degradation pathway of TC was proposed on the basis of the identified ***,the UV assisted heterogeneous Fenton-like process in Fe3O4@MsC improved the cycle of Fe^3+/Fe^2+ and activated the interfacial catalytic site,which eventually realized the enhancement of degradation and mineralization to tetracycline.

关键词： Fe3O4 Carbon skeleton of maize straw,Heterogeneous Fenton-like catalyst UV irradiation Degradation of tetracycline

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THE LEAsT sQUAREs EsTIMATOR FOR AN ORNsTEIN-UHLENBECK PROCEss DRIVEN BY A HERMITE PROCEss WITH A PERIODIC MEAN

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Acta Mathematica scientia 2021年第2期41卷 517-534页

作者： Guangjun sHEN Qian yu Zheng TANG Department of Mathematics Anhui Normal UniversityWuhu 241000China school of statistics East China Normal UniversityShanghai 200062China school of Mathematics and Finance Chuzhou UniverstyChuzhou 239012China

We consider the least square estimator for the parameters of Ornstein-Uhlenbeck processes dY_(s)=(∑_(j=1)^(k)μ_(j)φ_(j)(s)-βY_(s))ds+dZ_(s)^(q,H),driven by the Hermite process Z_(s)^(q,H)with order q≥1 and a Hurst index H∈(1/2,1),where the periodic functionsφ_(j)(s),,j=1,...,κare bounded,and the real numbersμ_(j),,j=1,...,κtogether withβ>0 are unknown *** establish the consistency of a least squares estimation and obtain the asymptotic behavior for the *** also introduce alternative estimators,which can be looked upon as an application of the least squares *** terms of the fractional Ornstein-Uhlenbeck processes with periodic mean,our work can be regarded as its non-Gaussian extension.

关键词： Least squares estimator consistency asymptotic distribution Ornstein-Uhlenbeck processes Hermite processes

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Highly sensitive Protein sensor Based on Thermally-Reduced Graphene Oxide Field-Effect Transistor

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Nano Research 2011年第10期4卷 921-930页

作者： shun Mao Kehan yu Ganhua Lu Junhong Chen Department of Mechanical Engineering University of Wisconsin-Milwaukee 3200 N. Craraer St. Milwaukee WI 53211 USA

We report the fabrication of a highly sensitive field-effect transistor （FET） biosensor using thermally-reduced graphene oxide （TRGO） sheets functionalized with gold nanoparticle （NP）-antibody conjugates. Probe antibody was labeled on the surface of TRGO sheets through Au NPs and electrical detection of protein binding （Immunoglobulin G/IgG and anti-lmmunoglobulin G/anti-lgG） was accomplished by FET and direct current （dc） measurements. The protein binding events induced significant changes in the resistance of the TRGO sheet, which is referred to as the sensor response. The dependence of the sensor response on the TRGO base resistance in the sensor and the antibody areal density on the TRGO sheet was systematically studied, from which a correlation of the sensor response with sensor parameters was found： the sensor response was more significant with larger TRGO base resistance and higher antibody areal density. The detection limit of the novel biosensor was around the 0.2 ng/rnL level, which is among the best of,＇eported carbon nanomaterial-based protein sensors and can be further optimized by tuning the sensor structure.

关键词： Biosensor thermally-reduced graphene oxide field-effect transistor protein detection

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Effect of Intra-Dot Coulomb Interaction on Andreev Reflection in Normal-Metal/Quantum-Dot/superconductor system

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Communications in Theoretical Physics 2001年第7期36卷 101-108页

作者： ZHU yu sUN Qing-Feng LIN Tsung-Han state Key Laboratory for Mesoscopic Physics and Department of Physics Peking University Beijing 100871 China State Key Laboratory for Mesoscopic Physics and Department of Physics Peking University Beijing 100871 China State Key Laboratory for Mesoscopic Physics and Department of Physics Peking University Beijing 100871 China

We investigate the effect of intra-dot Coulomb interaction on the Andreev reflection in a normalmetal/quantum-dot/superconductor (N-QD-s) system with multiple levels in the quantum dot, in the regime where the intra-dot interacting constant is comparable to the energy gap of superconducting lead. By using nonequilibrium Green function method, the averaged occupation of electrons in the quantum dot and the Andreev reflection (AR) current are studied. Comparing to the case of non-interacting quantum dot, the system shows significant changes for the a two-step-like behavior; and the I-Vg shows two groups of peaks, separated by U and with equal heights, where Vg is the gate voltage and U denotes the intra-dot Coulomb interaction constant. (ii) For finite bias voltage, dips, superposed V ≥ U/2, extra AR current peaks occur between the two groups of the peaks. Besides, the properties of the heights of the AR current peaks are more complicated.

关键词： Coulomb interactions, Andreev reflection, normal-metal/quantum-dot/superconductor system

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Novel high-resolution DOA estimation using subspace projection method

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 110-116页

作者： sI Wei-jian LAN Xiao-yu ZOU Yan College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China No. 91404 Army Qinhuangdao 066000 China

The performance of multiple signal classification （MUsIC） algorithm with regard to solving closely spaced direction of arrivals （DOAs） depends strongly upon the signal-to-noise ratio （sNR） and snapshots. In order to solve this problem, a method by reconstructing the spatial spectrum function with both noise subspace and signal subspace is presented in this paper. The key idea is to apply the full information contained in covariance matrix and change the projection weights of steering vector on the noise and signal subspace by their revised eigenvalues, respectively. Comparing with the MUsIC algorithm, it does not increase any computational complexity either, and remarkably, it has the advantages of simultaneously reducing noise and keeping the high-resolution ability under low sNR and small sample sized scenarios. simulation and experiment results are included to demonstrate the superior performance of the proposed algorithm.

关键词： direction &arrival (DOA) multiple signal classification low sNR resolution subspace projection

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A New series of Mo-free 21.5Cr-3.5Ni-xW-0.2N Economical Duplex stainless steels

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Journal of Iron and steel Research International 2014年第1期21卷 69-75页

作者： Zi-xing ZHANG Qing-xuan RAN yu-lai XU Xiao-jiang yu Da-wei JIANG Xue-shan XIAO Laboratory for Microstructures Institute of MaterialsShanghai University

A new series of economical Mo-free duplex stainless steels 21.5Cr-3.5Ni-xW-0. 2N （x = 1.8 -- 3. 0, mass%） have been developed. The effects of W on mechanical properties and corrosion resistance were investigated, and the microstructures were analyzed by optical microscopy, X-ray diffraction, transmission electron microscopy and electron backscatter diffraction. The designed steels have a balanced ferrite-austenite relation and are free of sigma phase after solution treatment at 750--1 300 ~C for 30 min followed by water-quenching, whereas a small number of Cr23 C~ precipitates were found after solution treatment at 750 ~C. After solution treatment at 1050 ℃, the steel with 1.8~ （mass percent） W exhibits the highest room temperature tensile strength due to the strongest work hardening effect, while the steel with 3.0% （mass percent） W exhibits the highest fracture elongation owing to the transformation-in- duced plasticity （TRIP） effect. The ductile-brittle transition （DBT） and martensite transformation are respectively found in the ferrite and austenite, which deteriorates the impact properties of the steels with the increase of W con- tent. The corrosion resistance of the designed steels is improved with the increase of W content. The pitting resistance of austenite is obviously better than that of ferrite for the designed alloys. Among the designed steels, the steel with 1.8% （mass percent） W is found to be an optimum steel with excellent comprehensive properties and lowest production cost.

关键词： economical duplex stainless steel tungsten mechanical property pitting corrosion resistance

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