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Visualizing nanopore blinkings in parallel:a high-throughput nanopore array potential for ultra-rapid DNA sequencing

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Science Bulletin 2015年第23期60卷 2067-2068页

作者： Jing-juan Xu State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing University

Upon finishing the sequencing of the first complete human genome in 2004[1],the demand for fast DNA reading with less than$1,000 has been fueled by the ever-increasing awareness for personalized medicine and clinical diagnosis[2,3].Plenty of sequencing techniques,from the original Sanger sequencing method to novel sequencing-by-synthesis technologies(Roche,Solexa,SOLi D,etc.)[3],have been developed rapidly in past decades,which are sug-

关键词： DNA测序纳米孔阵列高通量可视化超快速人类基因组测序平行临床诊断

Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

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Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： juan Liao Mengmeng Tian Xin Xue School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment Microstructure Intermetallic compounds

Hot-cracking susceptibility and shear fracture behavior of dissimilar Ti6Al4V/AA6060 alloys in pulsed Nd:YAG laser welding

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Chinese Journal of Aeronautics 2021年第4期34卷 375-386页

作者： Xin XUE Xinyong WU juan LIAO School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China Fujian Nebula Electronics Co. Ltd.Fuzhou 350015China

Laser welding of dissimilar titanium/aluminum alloys has been employed at an increasing rate,particularly in the aerospace industry,owing to its advantages in terms of current design flexibility and fuel/cost *** major problem with dissimilar Ti/Al welds arises from the difference in the thermal expansion and contraction of the two metals,which leads to hot-cracking susceptibility and the mitigation of the mechanical property after *** the present study,pulsed Nd:YAG laser welding of Ti6 Al4 V and AA6060 has been ***-cracking susceptibility in the heat affected zone and the shear fracture behavior of the lap joints were investigated through microstructural characterization and mechanical *** results indicate that the hot cracking tendency can be reduced by increasing the pulse peak power(7.5–8.5 kW)and the laser point diameter(0.8–1.0 mm)with specific pulse duration and *** alternative control strategy for less hot cracks in the Ti/Al lap joint can be to increase the weld width and decrease the cooling rate during *** shear fracture of the Ti/Al lap joint is likely to occur along the lower side path of the weld interface with decreasing weld surface collapsed amount and increasing aluminum base metal melt depth.

关键词： Aluminum alloy Hot-cracking susceptibility Pulsed Nd:YAG laser welding Shear fracture behavior Titanium alloy

Precise drag prediction of airfoil flows by a new algebraic model

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Acta Mechanica Sinica 2020年第1期36卷 35-43页

作者： Meng-juan Xiao Zhen-Su She State Key Laboratory for Turbulence and Complex Systems College of EngineeringPeking UniversityBeijing100871China

We report the results of accurate prediction of lift(C L)and drag(C D)coefficients of two typical airfoil flows(NACA0012 and RAE2822)by a new algebraic turbulence model,in which the eddy viscosity is specified by a stress length(SL)function predicted by structural ensemble dynamics(SED)*** accuracy of the prediction of C D with error of a few counts(one count is 10−4)and of C L with error under 1%-2%are uniformly obtained for varying angles of attack(AoA),indicating an order of magnitude improvement of drag prediction accuracy compared to currently used models(typically around 20 to 30 counts).More interestingly,the SED-SL model is distinguished with fewer parameters of clear physical meaning,which quantify underlying turbulent boundary layer(TBL)with a universal multi-layer structure,and is thus promising to be more easily generalizable to complex *** use of the new model for the calibration of flow condition in experiment and the extraction of flow physics from numerical simulation data of aeronautic flows are discussed.

关键词： Lift and drag coefficients Airfoil Flows Stress Length Structural ensemble dynamics

On the role of endogenous neurotoxins and neuroprotection in Parkinson's disease

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Neural Regeneration Research 2017年第6期12卷 897-901页

作者： juan Segura-Aguilar Molecular and Clinical Pharmacology ICBM Faculty of Medicine University of Chile

For 50 years ago was introduced L-3,4-dihydroxyphenylalanine（L-dopa） in Parkinson＇s disease treatment and during this significant advances has been done but what trigger the degeneration of the nigrostriatal system remain unknown. There is a general agreement in the scientific community that mitochondrial dysfunction, protein degradation dysfunction, alpha-synuclein aggregation to neurotoxic oligomers, neuroinflammation, oxidative and endoplasmic reticulum stress are involved in the loss of dopaminergic neurons containing neuromelanin in Parkinson＇s disease. The question is what triggers these mechanisms. The age of normal onset in idiopathic Parkinson＇s disease suggests that environmental factors such as metals, pollutants or genetic mutations cannot be involved because these factors are related to early onset of Parkinsonism. Therefore, we have to search for endogenous neurotoxins and neuroprotection in order to understand what trigger the loss of dopaminergic neurons. One important feature of Parkinson＇s disease is the rate of the degenerative process before the motor symptoms are evident and during the disease progression. The extremely slow rate of Parkinson＇s disease suggests that the neurotoxins and the neuroprotection have to be related to dopamine metabolism. Possible candidates for endogenous neurotoxins are alpha-synuclein neurotoxic oligomers, 4-dihydroxyphenylacetaldehyde and ortho-quinones formed during dopamine oxidation to neuromelanin. Vesicular monoamine transporter-2, DT-diaphorase and glutathione transferase M2-2 seems to be the most important neuroprotective mechanism to prevent neurotoxic mechanism during dopamine oxidation.

关键词： dopamine endogenous endoplasmic degeneration reticulum extremely glutathione Dopamine transporter metabolism

Calculating the Wave Force on Partially Immersed Large-Scale Horizontal Cylinders

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China Ocean Engineering 2021年第2期35卷 291-300页

作者： LIU Bi-jin FU Dan-juan School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China

Large-scale interceptors constitute the main structure of offshore self-driven floating marine litter collection devices,and the structural stability of such interceptors under the action of waves directly influences the overall safety of the *** the ratio of the diameter of a horizontal cylinder in such interceptors to the incident wavelength is larger than 0.25,the wave force can be calculated by using the diffraction theory,by considering the problem as that of the interaction between the waves and a partially immersed large-scale horizontal *** this study,an analytical approach to calculate the wave force on a partially immersed large-scale horizontal cylinder was formulated by using the stepwise approximation *** model tests were conducted to investigate the effects of different factors(wave height,period,and immersion depth)on the wave force on a large-scale horizontal cylinder under conditions involving short-period *** results show that both horizontal and vertical wave forces on the cylinder increase as the wave height(immersion depth)increases in most *** vertical wave force decreases with the decrease of the *** the horizontal wave force,it increases with the decrease of the period when the wavelength is larger than the diameter of the cylinder and decreases with the decrease of the period when the wavelength is smaller than the diameter of the cylinder.

关键词： wave force large-scale horizontal cylinder diffraction theory partial immersion stepwise approximation method

Research on the measurement of the price change of telecom services in China

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 110-113页

作者： ZHAO Hui-juan Management Department Xi'an University of Posts and TelecommunicationsXi'an 710061 China

It is difficult to measure the total change of the telecom service price （TSP） in China due to the complexity of TSP and the diversity of telecom service. This article analyzes the relation between telecom service revenue and traffic volumes of telecom service and deduces the method of measuring the total change in tendency of telecom price, which is based on the consumer＇s actual payment for telecom services. After describing the changing trend of TSP with the time series data from 1949 to 2000, the TSP showed a continuous declining tendency during 1949～1975. In contrast, the TSP showed a rising tendency from 1976 to 1991 and a sharp declining trend after 1992. Empirical tests and actual background of telecom reform support the results.

关键词： price telecom service price revenue traffic volumes of telecom service

Numerical study on indoor environment and thermal comfort in train station waiting hall with two different air-conditioning modes

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Building Simulation 2021年第2期14卷 337-349页

作者： Biyao Zhuang juan Shi Zhenqian Chen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education of China School of Energy and EnvironmentSoutheast UniversityNanjing210096China

With the increasing size of the waiting hall,the large-area use of transparent envelope materials makes the interior surface temperature of the envelope too high,which puts forward higher requirements for the control of environment and thermal comfort *** this paper,the characteristics of indoor temperature distribution,relative humidity distribution and thermal comfort under the all air system(AAs)and the radiant floor cooling and wall cooling combined with air supply system(RC/ASs)were investigated in the large *** computational fluid dynamics(CFD)method was used,and the performance of the CFD model was validated by comparing the measured results with CFD simulation results in the *** numerical results clearly showed that the temperature and relative humidity indoors could satisfy the design requirement both in the AAs and RC/*** indoor air distribution in most areas under the RC/ASs was more uniform based on the indoor heat and humidity requirements under the cooling load of measured *** the AAs,the total cooling capacity of air conditioning unit was the highest when indoor thermal comfort was the best,that meant that to achieve the best working condition,the air-conditioning system need high energy ***,the RC/ASs addressed the problem that the temperature around the seated passengers in the waiting area was relatively high in the *** paper will provide reference for the air conditioning system design in the similar large spaces in the future.

关键词： radiant floor cooling radiant wall cooling large spaces thermal comfort

Effects of Variable Jet Nozzle Angles on Cross-Flow Suppression and Heat Transfer Enhancement of Swirl Chamber

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Journal of Thermal Science 2022年第1期31卷 214-223页

作者： XIAO Kun HE juan FENG Zhenping Institute of Turbomachinery School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

This paper investigated the effects of variable jetting nozzle angles on the cross-flow suppression and heat transfer enhancement of swirl cooling in gas turbine leading edge. The swirl chamber with vertical jet nozzles was set as the baseline, and its flow fields and heat transfer characteristics were analyzed by 3D steady state Reynolds-averaged numerical methods to reveal the mechanism of cross-flow weakening the downstream jets and heat transfer. On this basis, the flow structure on different cross sections and heat transfer characteristics of swirl chamber with variable jetting nozzle angels were compared with the baseline swirl chamber. The results indicated that for the baseline swirl chamber the circumferential velocity gradually decreased and the axial velocity gradually increased, and the cross-flow gradually formed. The cross-flow deflected the downstream jets and drawn them to the center of the chamber, thus weakening the heat transfer. For swirl chamber with variable jetting nozzle angles, the air axial velocity is axial upstream, opposite to the mainstream, so that the impact effects of cross-flow on the jets were reduced, and the heat transfer was enhanced. Furthermore, with the increase of axial velocity along the swirl chamber, the jetting nozzle angle also gradually increased, as well as the effect of cross-flow suppression, which formed a relative balance. For all swirl chambers with variable jet nozzle angles, the thermal performance factors were all larger than 1, which indicated the heat transfer was enhanced with less friction increment.

关键词： swirl cooling cross-flow heat transfer enhancement variable jet nozzle angle