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Preliminary Study of a Hybrid Helicon-ECR Plasma Source

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Plasma Science and Technology 2016年第8期18卷 832-836页

作者： A.M.HAlA l.OKSUZ zhu Ximing The National Center for Applied Physics Material Science Research InstituteKing Abdul Aziz City for Science and Technology(KACST) Süleyman Demirel University Science and Literature FacultyPhysics Department Institute for Plasma and Atomic Physics Ruhr University

A new type of hybrid discharge is experimentally investigated in this work. A helicon source and an electron cyclotron resonance（ECR） source were combined to produce plasma. As a preliminary study of this type of plasma, the optical emission spectroscopy（OES） method was used to obtain values of electron temperature and density under a series of typical conditions. Generally,it was observed that the electron temperature decreases and the electron density increases as the pressure increased. When increasing the applied power at a certain pressure, the average electron density at certain positions in the discharge does not increase significantly possibly due to the high degree of neutral depletion. Electron temperature increased with power in the hybrid *** mechanisms of these preliminary observations are discussed.

关键词： helicon plasma ECR hybrid discharge

Clinical characteristics of coronavirus disease 2019 in patients aged 80 years and older

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Journal of Integrative Medicine 2020年第5期18卷 395-400页

作者： jian-zhong Dang Gang yan zhu Ying jie yang Fang Zheng Department of Critris Renrmin Haspital of Wuhan UniversilyWuhan 430060Hubei ProvinceChina Departmemt of Peiarics.Union Hospital.Tongi Medical Cllege.Huazhong Univrsity of Science and Technology.Wuhan 430022 Hubei Province China

Objective: Coronavirus disease 2019(COVID-19) has raised concern around the world as an epidemic or pandemic. As data on COVID-19 has grown, it has become clear that older adults have a disproportionately high rate of death from COVID-19. This study describes the early clinical characteristics of COVID-19 in patients with more than 80 years of ***: Epidemiological, clinical, laboratory, radiological, and treatment data from 17 patients diagnosed with COVID-19 between January 20 and February 20, 2020 were collected and analyzed retrospectively. Treatment outcomes among subgroups of patients with non-severe and severe symptoms of COVID-19 were ***: Of the 17 hospitalized patients with COVID-19, the median age was 88.0 years(interquartile range, 86.6–90.0 years;range, 80.0–100.0 years) and 12(70.6%) were men. The age distribution of patients was not significantly different between non-severe group and severe group. All patients had chronic pre-existing conditions. Hypertension and cardiovascular diseases were the most common chronic conditions in both subgroups. The most common symptoms at the onset of COVID-19 were fever(n = 13;76.5%), fatigue(n = 11;64.7%), and cough(n = 5;29.4%). lymphopenia was observed in all patients, and lymphopenia was significantly more severe in the severe group than that in non-severe group(0.4×10~9/l vs 1.2×10~9/l, P = 0.014). The level of serum creatinine was higher in the severe group than in the non-severe group(99.0 lmol/l vs 62.5 lmol/l, P = 0.038). The most common features of chest computed tomography images were nodular foci in 10(58.8%) patients and pleural thickening in 7(41.2%) patients. All patients received antiviral therapy, while some patients also received intravenous antibiotics therapy(76.5%), Chinese medicinal preparation therapy(lianhuaqingwen capsule, 64.7%), corticosteroids(35.3%) or immunoglobin(29.4%). Eight patients(47.1%) were transferred to the intensive care unit because of complications. Ten

关键词： Coronavirus 2019-nCoV SARS-CoV-2 COVID-19 Older patients

THE DISTRIBUTION FUNCTIONS FOR THE lINEAR COMPlEXITY OF PERIODIC SEQUENCES

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Journal of Electronics(China) 2012年第3期29卷 211-214页

作者： yang Minghui zhu Shixin School of Computer & Information Hefei University of Technology Hefei 230009 China School of Mathematics Hefei University of Technology Hefei 230009 China

linear complexity is an important standard to scale the randomicity of stream ciphers. The distribution function of a sequence complexity measure gives the function expression for the number of sequences with a given complexity measure value. In this paper, we mainly determine the distribution function of sequences with period over using Discrete Fourier Transform (DFT), where and the characteristics of are odd primes, gcd and is a primitive root modulo The results presented can be used to study the randomness of periodic sequences and the analysis and design of stream cipher.

关键词： linear complexity Periodic sequences Discrete Fourier Transform (DFT)

Construction of NIR luminescent nanoscale lanthanide complexes with new flexible Schiff base ligands

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Journal of Rare Earths 2020年第2期38卷 143-147页

作者： Bichen Yuan Junbin Tao Fei Wang Chaoqun zhu Min li Xiaoping yang Zhejiang Key laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Four mono-and bi-nuclear lanthanide complexes [lnl1(No3)(H2O)DMF](ln=Nd(1) and Yb(2)) and[ln2(l2)2(OAc)2](ln=Nd(3) and Yb(4)) were synthesized by using two new Schiff base ligands with long(CH2)2 NH(CH2)2 *** lengths of the Schiff base ligands are about 1.8 *** bi-nuclear lanthanide complexes 3 and 4 have nanoscale structures with sizes of approximately 0.7 nm×1.1 nm×1.6 *** 3,the molar ratio of Nd:Br:O obtained by the energy dispersive X-ray spectroscopy analysis is in agreement with the crystal *** chromogenic Schiff base ligands in1-4 can efficiently transfer energy to lanthanide ions,thus,these complexes exhibit the typical NIR luminescence of lanthanide ***,3 and 4 have higher NIR emission quantum yields(Φem)than 1 and 2,respectively.

关键词： Construction Schiff base ligands lanthanide complexes Nanoscale structures NIR luminescence Rare earths

Strengthening and toughening mechanism of a Cu-bearing high-strength low-alloy steel with refined tempered martensite/bainite(M/B)matrix and minor inter-critical ferrite

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Journal of Iron and Steel Research International 2021年第4期28卷 464-478页

作者： Fei zhu Feng Chai Xiao-bing luo Zheng-yan Zhang Cai-fu yang Department of Structural Steels Central Iron and Steel Research InstituteBeijing 100081China

The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel,subjected to a novel multistage heat treatment including quenching(Q),lamellarization(l)and tempering(T),is *** strength of 989.5 MPa and average toughness at-80℃of 41 J were obtained in this steel after quenching and tempering(QT)heat *** QlT gained a little lower yield strength(982.5 MPa),but greatly enhanced average toughness at-80℃(137 J).To further clarify the strengthening and toughening mechanisms in specimen QlT,parameters of microstructural characteristic and crack propagation process were compared and analyzed for specimens Q,Ql,QT and *** microstructure of tempered martensite/bainite(M/B)in specimen QT changed to refined tempered M/B matrix mixed with minor IF(inter-critical ferrite)in specimen ***-rich precipitates existed in tempered M/B for both specimens QT and QlT,as well as in *** with QT,adding a lamellarization step before tempering made the effective grains of specimen QlT refined and also led to coarser Cu-rich precipitates in tempered M/B *** weaker strengthening effect of coarser Cu-rich precipitates should be a key reason for the slightly lower yield strength in specimen QlT than in specimen *** austenite was found in all specimens Q,Ql,QT and *** QlT showed purely ductile fracture mode at-80℃due to the refined effective *** greatly improved toughness is mainly attributed to the enhanced energy of crack *** combination of refined microstructure,softened matrix and deformation of minor'soft'IF during crack propagation led to the most superior toughness of specimen QlT among all specimens.

关键词： High-strength low-alloy steel Multistage heat treatment low-temperature toughness Strengthening mechanism Grain refinement Crack propagation

Inducer/Exducer Matching Characteristics inside Tandem Impellers of a Highly loaded Centrifugal Compressor

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Journal of Thermal Science 2020年第4期29卷 928-944页

作者： lI Ziliang ZHAO Shengfeng lU Xin’gen HAN Ge yang Chengwu zhu Junqiang Key laboratory of light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

A centrifugal compressor usually operates with low isentropic efficiency and a terrible stable operating range, resulting from the complex impeller flow structure companied with the intense interaction among the impeller and the diffuser downstream. In many studies, the potential of centrifugal compressor tandem-impeller configurations for improving the compressor has been demonstrated. Whereas, compared with the convincing results on the tandem-designed axial compressors, the results on tandem impellers are limited and contradictory. Very little insight has been provided into the flow mechanisms inside tandem impellers, which is considered to be the primary reason for the confusion in tandem impeller design and application. Tandem impellers are expected to exhibit a totally different behavior due to the intense aerodynamic interaction between the inducer and the exducer, which substantially contributes to the flow structure and the compressor performance change. In the present study, a numerical study of a highly-loaded centrifugal compressor with various tandem designs was conducted to explore the inducer/exducer matching characteristics and the underlying flow mechanism inside tandem impellers. Two tandem impeller design parameters, namely, the inducer/exducer clocking fraction and the axial gap(overlap), were considered in the tandem impeller design process. The tandem impeller was also compared to the existing conventional impeller which the tandem impeller was redesigned for. The results demonstrated that the tandem-designed impeller can improve the centrifugal compressor stage performance and intense inducer/exducer interaction can be observed with changes in the clocking fraction and the axial gap(overlap). The tandem impeller performance is sensitive to changes in axial gap(overlap) when the suction side of the exducer blade is circumferentially close to the inducer blade. The fundamental reason for the performance variation in the inducer and the exducer l

关键词： highly loaded centrifugal compressor tandem impeller inducer/exducer matching flow mechanism Kutta condition

Highly Sensitive and Selective Amperometric Sensor for Iodate Based on 9,10-Phenanthrenequinone Derived Graphene

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Chemical Research in Chinese Universities 2013年第1期29卷 132-138页

作者： WANG Hong-juan CHENG Na-na yang Xiao-yang lI Xiao-meng zhu lian-de Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

We reported on a new amperometric sensor for the sensitive and selective determination of iodate in table salt. The iodate sensor was constructed by the integration of a novel nanocomposite which was made from 9,10-phenanthrenequinone（PQ） and graphene（GP） with a glassy carbon electrode（GCE）. The synthesized graphene and the nanocomposite were well characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, Fourier transform infrared（FTIR） spectroscopy and Raman spectroscopy. We fully studied the electrochemical beha- vior and kinetic characteristics of the PQ/GP nanocomposite at GCE. The PQ/GP electrode shows a good electrochemical catalytic activity towards the reduction of iodate, which makes itself a sensitive and selective electrochemical sensor for iodate. The iodate sensor displays a high sensitivity（1.04 ***.l-1）, a low detection limit（1.0X 10-8 mol/l）, a rapid response（less than 2 s）, and a broad linear range（from 5.0X 10-8 mol/l to 6.0X 10-3 mol/l ）. In addition, the sensor is interference free. The practical application of the proposed sensor was tested by the detection of iodate in table salt.

关键词： 9,10-Phenanthrenequinone Graphene Amperometric sensor Iodate

Utilizing modified ubi1 introns to enhance exogenous gene expression in maize(Zea mays l.) and rice(Oryza sativa l.)

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Journal of Integrative Agriculture 2016年第8期15卷 1716-1726页

作者： PAN yang-yang CHEN Rui zhu li WANG Hai HUANG Da-fang lANG Zhi-hong Biotechnology Research Institute Chinese Academy of Agricultural Sciences Tianjin Institute of Agricultural Quality Standard and Testing Technology Tianjin Academy of Agricultural Sciences

supported by the National Natural Science Fund of China （30970231）;the Genetically Modified Organisms Breeding Major Project of China （2014ZX08003001）

关键词： maize intron-mediated enhancement ubil intron intron modification IME signals

Sample spinning to mitigate polarization artifact and interstitial-vacancy imbalance in ion-beam irradiation

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npj Computational Materials 2020年第1期6卷 107-117页

作者： Cui-lan Ren yang yang Yong-Gang li Ping Huai Zhi-Yuan zhu Ju li Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Key laboratory of Interfacial Physics and Technology Chinese Academy of SciencesShanghai 201800China National Center for Electron Microscopy Molecular FoundryLawrence Berkeley National LaboratoryBerkeleyCA 94720USA Key laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteShanghai 201204China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Accelerator-based ion-beam irradiation has been widely used to mimic the effects of neutron radiation damage in nuclear ***,ion radiation is most often monodisperse in the incoming ions’momentum direction,leading to excessive polarization in defect distribution,while the scattering under neutron irradiation is often more isotropic and has less radiation-induced *** of the excess-polarization as well as the damage non-uniformity artifact might be crucial for making the simulation of neutron radiation by ion-beam radiation more *** this work,a general radiation polarization theory in treating radiation as external polar stimuli is established to understand the natural material responses in different contexts,and the possibility to correct the defect polarization artifact in ion-beam *** by Magic Angle Spinning in Nuclear Magnetic Resonance,we present a precise sample spinning strategy to reduce the point-defect imbalance effect in ion-beam *** can be seen that with optimized surface inclination angle and the axis of sample rotation,the vacancy-interstitial population imbalance,as well as the damage profile non-uniformity in a designated region in the target are both *** is estimated that sample spinning frequency on the order of kHz should be sufficient to scramble the ion momentum monodispersity for commonly taken ion fluxes and dose rates,which is experimentally feasible.

关键词： beam vacancy momentum