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Small Prime Solutions of a Pair of Linear Equations in Five Prime Variables

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Acta Mathematica Sinica,English Series 2010年第3期26卷 569-578页

作者： Zhen cui hong Ze LI Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 P. R. China

Assume an additional congruent condition on the coefficients. We prove that the pair 5 of linear equations ∑j=1^5 αλjpj = bλ （λ= 1, 2） has solutions in primes pj satisfying pj 〈〈（｜b1｜＋｜b2｜＋1） maxλ,j ｜αλj｜^2318＋ε. This improves the exponent 79680 without assuming the additional condition of the second author＇s.

关键词： Diophantine equations Deuring-Heilbronn phenomenon large sieve inequality zero-free region

Structure and function of neuropeptide F in insects

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Journal of Integrative Agriculture 2020年第6期19卷 1429-1438页

作者： cui hong-ying ZHAO Zhang-wu Department of Entomology/MOA Key Lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China

In sect n europeptides are a group of brain n euro-regulatory factors,which plays very important roles in growth and developme nt,molting and metamorphosis,as well as mating and *** neuropeptide F(NPF),a multi-functional neuropeptide,is one of neuropeptides identified in numerous insect species,which plays important roles in feeding,metabolism,courtship,reproduction,aggression,ethanol sensitivity,locomotor circadian rhythms,learning and stress *** roles of NPF are implemented through NPF receptors(NPFR).The NPFR1,a G protein-coupled receptor with 7 transmembrane domai ns,is one of these receptors and is found to be imports nt for NPF *** NPF usually is con sisted of around 36-40 amino acid residues,but the short neuropeptide F(sNPF)consisted of 7-16 amino acid residues have also been found in some *** this review,the structure and function of both NPF and sNPF in in sects are discussed.

关键词： neuropeptide NPF sNPF NPFR1 insects

X-ray and optical plateaus following the main bursts in GRBs and SNe Ⅱ-P: a hint about similar late injection behaviors?

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Research in Astronomy and Astrophysics 2013年第6期13卷 671-679页

作者： Xiao-hong cui Ren-Xin Xu National Astronomical Observatories Chinese Academy of Sciences School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University

We analyze the emission plateaus in the X-ray afterglow light curves of gamma-ray bursts （GRBs） and those in the optical light curves of type Ⅱ plateau su- pernovae （SNe Ⅱ-P） in order to study whether they have similar late energy injection behaviors. We show that correlations of bolometric energies （or luminosities） between the prompt explosions and the plateaus for the two phenomena are similar. The energy emitted by SNe II-P are at the lower end of the range of possible energies for GRBs. The bolometric energies （or luminosities） in the prompt phase Eexpl （or Lexpl） and in the plateau phase E_plateau （or L_plateau） share relations of E_expl ∝E _0.73±0.14_plateau and L_expl ∝ L^-0.70_plateau. These results may indicate a similar late energy injection behavior that produces the observed plateaus in these two phenomena.

关键词： gamma rays: bursts -- supernovae: general -- methods: statistical

A new methodology for the CFD uncertainty analysis

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Journal of Hydrodynamics 2013年第1期25卷 131-147页

作者： YAO Zhen-qiu SHEN hong-cui GAO Hui School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology China Ship Scientific Research Center

With respect to the measurement uncertainty, this paper discusses the definition, the sources, the classification and the expressions of the CFD uncertainty. Based on the orthogonal design and the statistics inference theory, a new verification and validation method and the related procedures in the CFD simulation are developed. With the method, two examples of the CFD verification and validation are studied for the drag coefficient and the nominal wake fraction, and the calculation factors and their interactions which would significantly affect the simulation results are obtained. Moreover, the sizes of all uncertainty components resulting from the controlled and un-controlled calculation factors are determined, and the optimal combination of the calculation factors is obtained by an effect estimation in the orthogonal experiment design. It is shown that the new method can be used for the verification in the CFD uncertainty analysis, and can reasonably and definitely judge the credibility of the simulative result. As for CFD simulation of the drag coefficient and the nominal wake fraction, the results predicted can be validated. Although there is still some difference between the simulation results and the experiment results, its approximate level and credibility can be accepted.

关键词： CFD uncertainty verification validation

Tearing Toughness of Ductile Metals

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 150-155页

作者： cui-hong Li Qi-Qiang Duan Zhe-Feng Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

A new parameter, i.e., tearing toughness, was employed to characterize the mechanical properties of some ductile metals （Cu, Cu-2 wt% Be, Cu-Al alloys, and some steels） by using three-leg trousers tearing tests. The experi- mental results demonstrate that their tearing toughness is not a physical constant and shows a close relationship with the materials＇ types and microstructures. It can be inferred that the tearing toughness of different ductile metals has their respective variation range, expectantly, and may be represented by the comprehensive mechanical properties of strength and ductility for various ductile materials.

关键词： Ductile metals Strength Ductility Tearing toughness

Isolation and characterization of a new subunit of phycocyanin from Chroomonas placoidea

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Chinese Chemical Letters 2011年第10期22卷 1229-1232页

作者： Yun Yun Zhang Min Chen hong cui College of Chemical and Biological Sciences and Engineering Yantai University Yantai 264005 China Yantai Traditional Chinese Medical-science Hospital Yantai 264002 China

A new phycocyanin（PC） fluorescent subunit namedβ_2（18kDa） was isolated and characterized by both SDS-PAGE and isoelectric focusing（IEF） from a species of cryptophytic alga Chroomonas *** was separated and purified by ammonium sulfate sedimentation followed by two steps of Sephadex G-100 *** denatured in 4 mol/L urea for 48 h,PC was divided into two fractions by passing through a Sephacryl S-100 chromatography column *** blue fraction（S-1） containedβsubunits with a maximal absorbance at 595 nm in visible light *** the green fraction（S-2） enriched inαsubunits showed a characteristic long wavelength absorbance at 680-700 nm region and exhibited a relatively low molecular weight of 9.4（α_1） and 8.5 kDa（α_2）.Fraction S-1 also consisted of two different fluorescent subunits with molecular weight of 20.1 kDa（β_1） and 18 kDa （β_2） and differed from each other on isoelectric points of pH 5.7（ft） and 6.0（ft）,*** investigation of peptide sequence will help a lot in elucidating the new subunit ft that was smaller in size and more neutral than the known ft subunit,and may provide an alternative explanation in structure of cryptophytic phycobiliproteins.

关键词： Chroomonas placoidea Phycocyanin subunit Sephacryl S-100 chromatography SDS-PAGE IEF

Analysis of prediction performance in wavelet minimum complexity echo state network

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 59-66页

作者： cui hong-yan FENG Chen LIU Yun-jie Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications School of Information and Communication Engineering Beijing University of Posts and Telecommunications

Echo state network （ESN） has become one of the most popular recurrent neural networks （RNN） for its good prediction performance of non-linear time series and simple training process. But several problems still prevent ESN from becoming a widely used tool. The most prominent problem is its high complexity with lots of random parameters. Aiming at this problem, a minimum complexity ESN model （MCESN） was proposed. In this paper, we proposed a new wavelet minimum complexity ESN model （WMCESN） to improve the prediction accuracy and increase the practical applicability. Our new model inherits the characters of minimum complexity ESN model using the fixed parameters and simple circle topology. We injected wavelet neurons to replace the original neurons in internal reservoir and designed a wavelet parameter matrix to reduce the computing time. By using different datasets, our new model performed better than the minimum complexity ESN model with normal neurons, but only utilized tiny time cost. We also used our own packets of transmission control protocol （TCP） and user datagram protocol （UDP） dataset to prove that our model can deal with the data packet bit prediction problem well.

关键词： wavelet minimum complexity echo state network echo state network wavelet parameter matrix practical applicability

Delayed onset and fast rise of prompt optical-UV emission from gamma-ray bursts in molecular clouds

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Research in Astronomy and Astrophysics 2013年第1期13卷 57-70页

作者： Xiao-hong cui Zhuo Li Li-Ping Xin National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University

Observations imply that long ＂y-ray bursts （GRBs） originate from the explo- sions of massive stars, therefore they may occur in the molecular clouds where their progenitors were born. We show that the prompt optical-UV emission from GRBs may be delayed due to dust extinction, which can explain the observed optical delayed on- set and fast rise in GRB 080319B well. The density and the size of the molecular cloud around GRB 080319B are roughly constrained to be ~ 103 cm-z and ~ 8 pc, respectively. We also investigate other GRBs with prompt optical-UV data, and find similar values of the densities and sizes of the local molecular clouds. Future obser- vations of prompt optical-UV emission from GRBs on a timescale of subseconds, e.g. by UFFO-Pathfinder and SVOM-GWAC, will provide more evidence and probes of the local environments of GRBs.

关键词： radiation mechanisms: non-thermal -- gamma-rays: bursts -- dust: ex-tinction

Amniotic membrane transplantation for porous sphere orbital implant exposure

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第9期8卷 616-619页

作者： CHEN Yan-hong cui hong-guang Department of Eye Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310015 China

Objective: This study is aimed at describing the clinical outcome of amniotic membrane transplantation for exposure of porous sphere implants. Methods: A retrospective review of consecutive cases of porous sphere orbital implant exposure was carried out. Eight cases were presented between May 2004 and Oct. 2006 (5 males, 3 females; mean age 44.5 years). Six had enucleation and two had evisceration. Exposure occurred in two primary and six secondary. Orbital implant diameter was 22 mm in seven cases and 20 mm in one case. Six patients are with hydroxyapatite and two with high-density porous polyethylene (Medpor) orbital implants. The mean time from implantation to exposure was 1.1 months (range 0.8~2 months). All patients required surgical intervention. Results: The time of follow-up ranged from 3.0 to 28.0 months (mean 16.5 months). Amniotic membrane grafting successfully closed the defect without re-exposure in all of these patients. The grafts were left bare with a mean time to conjunctiva of about 1 month (range 0.8~1.5 months). Conclusion: Exposed porous sphere implants were treated suc-cessfully with amniotic membrane graft in all of patients. The graft is easy to harvest. This technique is useful, dose not lead to prolonged socket inflammation and infection, and it is valuable application extensively.

关键词： Amniotic membrane transplantation Orbital implants Exposure