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Possibility of Searching for Accreting White Dwarfs with the Chinese Space Station Telescope

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Research in Astronomy and Astrophysics 2022年第5期22卷 21-27页

作者： Wei Xie hai-Liang chen Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of the Chinese Academy of Sciences Beijing 100049China

Accreting WDs are very important for the studies of binary evolution,binary population synthesis and accretion *** far,there are a lot of accreting WD binaries with low accretion rates,such as cataclysmic variables,detected by different ***,few accreting WD binaries with high accretion rates have been *** this paper,we studied the spectrum properties of accreting WD binaries and investigated whether accreting WD binaries with high accretion rates can be detected by the Chinese Space Station Telescope(CSST).We found that some accreting WD binaries with high accretion rates can be distinguishable from other types of stars with(NUV-y,u-y),(NUV-r,u-g),(NUV-i,u-g),(NUV-z,u-g)and(NUV-y,u-g)color-color ***,some accreting WD binaries with high accretion rates can be detected by the CSST.

关键词： white dwarf stars whitedwarfs-binarystars close binarystars-low massstars low-massstar

PSG： a two-layer graph model for document summarization

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Frontiers of Computer Science 2014年第1期8卷 119-130页

作者： Heng chen hai JIN Feng ZHAO Service Computing Technology and System Lab & Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Graph model has been widely applied in docu- ment summarization by using sentence as the graph node, and the similarity between sentences as the edge. In this paper, a novel graph model for document summarization is presented, that not only sentences relevance but also phrases relevance information included in sentences are utilized. In a word, we construct a phrase-sentence two-layer graph structure model （PSG） to summarize document（s） . We use this model for generic document summarization and query-focused sum- marization. The experimental results show that our model greatly outperforms existing work.

关键词： relationship graph Markov random walk doc-ument summarization

Characterization of thermal-induced distorted face-centered cubic structure in pure titanium

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Journal of Iron and Steel Research International 2019年第6期26卷 653-658页

作者： hai-chen Wu Xiao-fang Bi School of Materials Science and Engineering Beihang University Beijing 100191 China

After 900 ℃ high-vacuum annealing and air cooling, a special band was observed in pure titanium. Energy-dispersive spectrum showed that the composition of the band and the matrix is the same. By tilting the band to different zone axes and taking selected-area electron diffraction (SAED) patterns, we found that the structure of the band is distorted face-centered cubic (fcc) with the lattice constants a, b, and c deviating slightly from each other on the basis of the analyses of the SAED patterns together with the tilting angles. The lattice constants a, b, and c are calculated based on the measurement of interplanar spacing according to high-resolution transmission electron microscopy (HRTEM) images. The orientation relation between the hexagonal-close-packed (hcp) matrix and the distorted fcc band is [11(2)0]hcp//[110]fcc and (0001)hcp//(1(1)1)fcc according to SAED analysis. The phase boundary between the matrix and the band was observed to demonstrate serrated configuration composed of two kinds of micro-steps: ((1)11)//(0002) and ((1)11)//(10(1)1) on the basis of Cs-corrected HRTEM characterization. The distorted fcc band is deduced to be a thermal-induced metastable phase transformed from the high-temperature body-centered cubic (bcc) structure during the allotropic transformation from bcc to hcp based on orientation relation analysis.

关键词： Titanium Transmission electron microscopy Distorted fee Phase boundary Formation mechanism

Dual-wavelength dual-indicator catalytic kinetic spectrophotometry for determination of trace Ru(Ⅲ)

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Rare Metals 2013年第6期32卷 605-608页

作者： hai-Yan chen Yu-Jing chen Ming Zhang School of Chemistry and Chemical Engineering Yangzhou University Department of Chemical Engineering Yangzhou Polytechnic InstituteYangzhou 225127 China School of Chemistry and Materials Science Ludong University

A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was *** method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine by potassium bromate in sulfuric *** absorbances of the catalytic and noncatalytic systems were measured at 510 and610 nm,*** the optimum conditions,the linear range of determination is 0–0.12 lgáml-1and the detection limit is 1.21 9 10-4lgá*** method was applied for the determination of trace Ru(III)in ore samples with satisfactory results.

关键词： Dual-wavelength Catalytic spectrophotometry Ru(III) Arsenazo I Indigo carmine

A wideband fast multipole boundary element method for half-space/plane-symmetric acoustic wave problems

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Acta Mechanica Sinica 2013年第2期29卷 219-232页

作者： Chang-Jun Zheng hai-Bo chen Lei-Lei chen Department of Modern Mechanics University of Science and Technology of China

This paper presents a novel wideband fast multipole boundary element approach to 3D half-space/planesymmetric acoustic wave *** half-space fundamental solution is employed in the boundary integral equations so that the tree structure required in the fast multipole algorithm is constructed for the boundary elements in the real domain ***,a set of symmetric relations between the multipole expansion coefficients of the real and image domains are derived,and the half-space fundamental solution is modified for the purpose of applying such relations to avoid calculating,translating and saving the multipole/local expansion coefficients of the image *** wideband adaptive multilevel fast multipole algorithm associated with the iterative solver GMRES is employed so that the present method is accurate and efficient for both lowand high-frequency acoustic wave *** for exterior acoustic problems,the Burton-Miller method is adopted to tackle the fictitious eigenfrequency problem involved in the conventional boundary integral equation *** on the implementation of the present method are described,and numerical examples are given to demonstrate its accuracy and efficiency.

关键词： Helmholtz equation·Boundary element method·Half-space/plane-symmetric problem·Wideband fast multipole method·Noise barrier

A Light-Weight Opportunistic Forwarding Protocol with Optimized Preamble Length for Low-Duty-Cycle Wireless Sensor Networks

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Journal of Computer Science & Technology 2017年第1期32卷 168-180页

作者： hai-Ming chen Li Cui Gang Zhou Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Department of Computer Science College of William and Mary Williamsburg VA 23185 U.S.A.

In wireless sensor networks, sensed information is expected to be reliably and timely delivered to a sink in an ad-hoc way. However, it is challenging to achieve this goal because of the highly dynamic topology induced from asynchronous duty cycles and temporally and spatially varying link quality among nodes. Currently some opportunistic forwarding protocols have been proposed to address the challenge. However, they involve complicated mechanisms to determine the best forwarder at each hop, which incurs heavy overheads for the resource-constrained nodes. In this paper, we propose a light-weight opportunistic forwarding （LWOF） scheme. Different from other recently proposed opportunistic forwarding schemes, LWOF employs neither historical network information nor a contention process to select a forwarder prior to data transmissions. It confines forwarding candidates to an optimized area, and takes advantage of the preamble in low-power-listening （LPL） MAC protocols and dual-channel communication to forward a packet to a unique downstream node towards the sink with a high probability, without making a forwarding decision prior to data transmission. Under LWOF, we optimize LPL MAC protocol to have a shortened preamble （LWMAC）, based on a theoretical analysis on the relationship among preamble length, delivery probability at each hop, node density and sleep duration. Simulation results show that LWOF, along with LWMAC, can achieve relatively good performance in terms of delivery reliability and latency, as a receiver-based opportunistic forwarding protocol, while reducing energy consumption per packet by at least twice.

关键词： wireless sensor network low duty cycle low power listening opportunistic forwarding

Investigation of migration of pollutant at the base of Suzhou Qizishan landfill without a liner system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 439-449页

作者： hai-jian XIE Yun-min chen Liang-tong ZHAN Ren-peng chen Xiao-wu TANG Ru-hai chen Han KE MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China College of Civil Engineering and Architeeture Zhejiang University Hangzhou 310058 China

We investigated migration of pollutant at the base of the Suzhou landfill after it had been operated for 13 years. The investigation was carried out by performing chemical analyses on the soil samples taken from the silty clay deposit. Concentrations of chloride, chemical oxygen demand （COD） and the heavy metals in the soil samples were determined using the standard methods. The experimental data showed that the maximum migration depth of chloride was more than 10 m, while the maximum migration depth of COD varied between 1 and 3.5 m. It is believed that the difference is attributed to the variation in diffusion rate and leachate-soil interaction. The chloride profiles also indicated that adveetion may be the dominant contaminant transport mechanism at this site. The total contents ofCu, Pb and Cr are very close to the background levels and the concentration values of these metals mainly are lower than the threshold values specified by the Chinese soil quality standard and the European one. The water-extractable concentrations of COD in the surface of the silty clay generally exceed the limit value specified by the Chinese standard. The concentrations of copper and chromium in pore water are 1-2 orders of magnitude less than the total concentrations of these heavy metals within the soils, implying that heavy metals are mainly adsorbed by the soil particles. Finally, remediation methods were suggested for this landfill site.

关键词： Uncontrolled landfill Field investigation Contaminant migration Soil contamination Heavy metals Organic contaminants Chloride

Effect of the medication injection site on treatment efficacy in pediatric cerebral palsy: conventional sites vs acupoints

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Journal of Traditional Chinese Medicine 2019年第5期39卷 716-721页

作者： Sun Yan chen hai Wu chengyan Teaching Office School of Rehabilitation MedicineHenan University of Chinese MedicineZhengzhou 450058China Prescription Traching and Research Section Institute of Literature in Chinese MedicineNanjing University of Chinese MedicineNanjing 210046China Prescription Traching and Research Section Institute of Literature in Chinese MedicineNanjing University of Chinese MedicineNanjing 210046China Department of Children's Rehabilitation The Third Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

OBJECTIVE: To analyze treatment effectiveness in terms of the medication injection site. METHODS: The medical records of 423 patients with cerebral palsy who were admitted to Maternal and Child Health Hospital between January 2009 and December 2016 were collected. All cases were divided into T1, T2, T3, and T4 groups based on the use of conventional medication sites and acupoints for administering injectable medicines. RESULTS: In the T1 group, patients received injections at conventional medication sites between 2009 and 2010. In the T2 group, patients received injections at conventional medication sites combined with acupoint injection therapy I from 2011 to 2012. In the T3 group, injection at conventional medication sites plus acupoint injection II was applied between 2013 and 2014. Acupoint injection only was used in the T4 group from 2015 to 2016. Therapeutic effects were statistically compared among the different injection procedures. The overall Gross Motor Function Measure (GMFM) and Fine Motor Function Measure (FMFM) scores were significantly improved after hospital discharge. The GMFM score was considerably higher in the T4 group than in the other groups (all P = 0.001 0.05). Meanwhile, the FMFM scores were significantly higher in the T2 and T4 groups than in the T1 and T3 groups (all P = 0.001 < 0.05). Site injection therapy can significantly improve gross and fine motor function in children with cerebral palsy. CONCLUSION: It is feasible to administer injectable medicines at acupoints instead of convention sites to enhance the therapeutic effect of treatment in patients with cerebral palsy.

关键词： Cerebral palsy Injections Acupuncture points Retrospective studies

An integrated pest management program for managing fusarium head blight disease in cereals

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Journal of Integrative Agriculture 2022年第12期21卷 3434-3444页

作者： chen A-hai Tofazzal ISLAM MA Zhong-hua State Key Laboratory of Rice Biology/Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of BiotechnologyZhejiang UniversityHangzhou 310058P.R.China Institute of Biotechnology and Genetic Engineering(IBGE) Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh

Fusarium head blight(FHB)is a worldwide devastating disease of small grain cereals and Fusarium graminearum species complex(FGSC)is the major pathogen causing the *** epidemics of FHB lead to the reduction of grain yield and economic ***,mycotoxins produced by the FHB pathogens are hazardous to the health of human and *** this review,we summarize the epidemiology of FHB,and introduce effects of this disease on economy,environment and food *** focus on the integrated management approaches for controlling FHB including agronomic practices,resistant cultivars,chemical control,and *** addition,we also discuss the potential novel management strategies against FHB and mycotoxin.

关键词： fusarium head blight Fusarium graminearum integrated pest management program mycotoxins