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Chemical Research in Chinese Universities 2007年第6期23卷 665-668页

作者： GUO Xu DUAN hai-feng sun hai CAO Jun-gang LIN Ying-jie Department of Organic Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A novel BrФnsted acidic ionic liquid（IL） based on the cyclic guanidinium cation has been synthesized. This IL, as a strong BrФnsted acid catalyst or solvent, shows high catalytic activity and biphsaic behavor in the esterifications of carboxylic acids and alcohols. The produced esters as a separate phase can be conveniently decanted out from the IL and the IL is recyclable without any loss of catalytic activity.

关键词： BrФnsted acid Ionic liquid Guanidinium Fisher esterification

Synthesis and characterization of α-N,N-dihydroxyethylaminopropyl-ω-butylpolydimethylsiloxanes

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Chinese Chemical Letters 2008年第1期19卷 47-50页

作者： Yi Tao Yu Qing Si Zhang Meng Zhang hai feng sun School of Chemical Engineering Shandong Institute of Light Industry Jinan 250100 China School of Chemistry and Material Southern Yangtz University Wuxi 214122 China

A series of α-N,N-dihydroxyethylaminopropyl-ω-butylpolydimethylsiloxanes with different molecular weight were synthesized. The preparation included five steps which were hydroxyl protection, alkylation, anionic ring-opening polymerization, hydrosilylation and deprotection. The structure of reaction products was characterized by FT-IR, GC, 1H NMR. 2007 Qing Si Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Hydroxyl protection Alkylation Anionic ring-opening polymerization Hydrosilylation α-N,N-dihydroxy-ethylaminopropyl-ω- butylpolydimethylsiloxanes

Hydrothermal synthesis and characterization of nano-petal nickel hydroxide

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Rare Metals 2015年第9期34卷 667-672页

作者： Wen-Xiu He Yong-Qiang Zhang Qian-Qing Liang Wen-Quan Jiang hai-feng sun School of Chemistry Engineering Inner Mongolia University of Science and Technology Analysis & Measurements Research Center General Rearch Institute for Non-Ferrous Metals

The current article reports a preparation method of nano-petal nickel hydroxide, which was synthesized using urea as a precipitator by hydrothermal method. Nickel hydroxide samples with different microstructural characteristics were prepared by changing molar ratio of nickel/urea and reaction time. The prepared nickel hydroxide samples were characterized using X-ray diffraction(XRD) and scanning electron micrography(SEM).Electrochemical performances of the samples were then determined under charging–discharging rate of 0.2C. The influences of different conditions of the hydrothermal synthesis method on microstructure parameters of nickel hydroxide were analyzed, while relationships between microstructural characteristics parameters of nickel hydroxide and the electrochemical performances of nickel electrode were also explored.

关键词： Hydrothermal synthesis Nano-petal Electrochemical

Numerical simulation analysis of covering rock strata as mining steep-inclined coal seam under fault movement

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中国有色金属学会会刊：英文版 2011年第S3期21卷 556-561页

作者： MA feng-hai, sun Li, LI Dun College of Civil and Architectural Engineering, Dalian University, Dalian 116622, China College of Civil and Architectural Engineering Dalian University Dalian 116622 China

The fault is one important factor for the stability of overburden strata caused by steeply inclined coal seam. The stress and displacement change of overburden strata caused by steeply-inclined coal seam mining activity under faulting was simulated by FLAC2D finite differential program on the basis of Zhaogezhuang mining example belonging to Kailuan Mining Group. From the results, the stress and displacement clouding image after mining became complex because of the fault, that is, a kind of weak structural plane. The stress concentration region concentrated around the goaf, and also around the fault plane. As the mining depth increases, the stress and displacement within the fault zone change significantly. This movement and deformation characteristic of overburden strata can provide theoretical basis for the similar mining condition.

关键词： fault steep-inclined coal seam numerical simulation overburden distortion

Synthesis and characterization ofα-{ 3-[2-hydroxy-3-(N-methyl-N-hydroxy-ethylamino)propoxy]propyl}-ω-butylpolydimethylsiloxanes

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Chinese Chemical Letters 2008年第10期19卷 1196-1198页

作者： hai feng sun Qing Si Zhang Meng Zhang Yi Tao Yu Jian Ping Zong School of Chemical Engineering Shandong Institute of Light IndustryJinan 250100China School of Chemistry and Material Jiangnan UniversityWuxi 214122China

α-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}-α-butylpolydimethylsiloxanes III with various molecu-lar weights were prepared by epoxy addition ofα-[3-(2,3-epoxy-propoxy)propyl]-α-butylpolydimethylsiloxanesⅡand *** each step,the outcome compounds were characterized through FT-IR and NMR spectra,the results showed that each step was successfully carried out and objective products were achieved.

关键词： Anionic ring-opening polymerization Hydrosilylation Epoxy addition α-{3-[2-Hydroxy-3-(N-methyl-N-hydroxyethylamino)pro-poxy]propyl}-to-butylpolydimethylsiloxanes

NfvInsight:A Framework for Automatically Deploying and Benchmarking VNF Chains

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Journal of Computer Science & Technology 2022年第3期37卷 680-698页

作者： Tian-Ni Xu hai-feng sun Di Zhang Xiao-Ming Zhou Xiu-feng Sui Sa Wang Qun Huang Yun-Gang Bao State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China Peng Cheng Laboratory Shenzhen 518055China Department of Computer Science and Technology Peking UniversityBeijing 100871China

With the advent of virtualization techniques and software-defined networking(SDN),network function virtualization(NFV)shifts network functions(NFs)from hardware implementations to software appliances,between which exists a performance *** to narrow the gap is an essential issue of current NFV ***,the cumbersomeness of deployment,the water pipe effect of virtual network function(VNF)chains,and the complexity of the system software stack together make it tough to figure out the cause of low performance in the NFV *** pinpoint the NFV system performance,we propose NfvInsight,a framework for automatic deployment and benchmarking VNF *** framework tackles the challenges in NFV performance *** framework components include chain graph generation,automatic deployment,and fine granularity *** design and implementation of each component have their *** the best of our knowledge,we make the first attempt to collect rules forming a knowledge base for generating reasonable chain *** deploys the generated chain graphs automatically,which frees the network operators from executing at least 391 lines of bash commands for a single *** diagnose the performance bottleneck,NfvInsight collects metrics from multiple layers of the software ***,we collect the network stack latency distribution ingeniously,introducing only less than 2.2%*** showcase the convenience and usability of NfvInsight in finding bottlenecks for both VNF chains and the underlying *** our framework,we find several design flaws of the network stack,which are unsuitable for packet forwarding inside one single server under the NFV *** optimization for these flaws gains at most 3x performance improvement.

关键词： network function virtualization(NFV) service chain performance bottleneck network stack latency

A novel period estimation method for X-ray pulsars based on frequency subdivision

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Frontiers of Information Technology & Electronic Engineering 2015年第10期16卷 858-870页

作者： Li-rong SHEN Xiao-ping LI hai-feng sun hai-yan FANG Meng-fan XUE School of Aerospace Science and Technology Xidian University

Period estimation of X-ray pulsars plays an important role in X-ray pulsar based navigation （XPNAV）. The fast Lomb periodogram is suitable for period estimation of X-ray pulsars, but its performance in terms of frequency resolution is limited by data length and observation time. Longer observation time or oversampling can be employed to improve frequency analysis results, but with greatly increased computational complexity and large amounts of sampling data. This greatly restricts real-time autonomous navigation based on X-ray pulsars. To resolve this issue, a new method based on frequency subdivision and the continuous Lomb periodogram （CLP） is proposed to improve precision of period estimation using short-time observation data. In the proposed method, an initial frequency is first calculated using fast Lomb periodogram. Then frequency subdivision is per- formed near the initial frequency to obtain frequencies with higher precision. Finally, a refined period is achieved by calculating the CLP in the obtained frequencies. Real data experiments show that when observation time is shorter than 135 s, the proposed method improves period estimation precision by 1-3 orders of magnitude compared with the fast Lomb periodogram and fast Fourier transform （FFT） methods, with only a slight increase in computational complexity. Furthermore, the proposed method performs better than efsearch （a period estimation method of HEAsoft） with lower computational complexity. The proposed method is suitable for estimating periods of X-ray pulsars and obtaining the rotation period of variable stars and other celestial bodies.

关键词： Pulsar navigation Period estimation Frequency subdivision Continuous Lomb periodogram

Validation of Reliable Reference Genes for Accurate Normalization in RT-qPCR Analysis of Codonopsis pilosula

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Chinese Herbal Medicines 2017年第3期9卷 226-235页

作者： Ling-ya Cao Xiao-xiao Li Dong Wang hai-feng sun Jian-ping Gao School of Basic Medical Science Shanxi Medical University School of Pharmacy Shanxi Medical University College of Chemistry & Chemical Engineering Shanxi University

Objective To identify reliable reference genes（RGs） for normalization of real-time PCR（RT-q PCR） data in Codonopsis pilosula. Methods The expression profiles of 10 candidate RGs（GAPDH, ACT, α-TUB, β-TUB, UBQ, CYP, EF-1α, NAC, F-box and PP2A） were examined in C. pilosula during the phenological period. The raw materials examined included roots, stems, leaves, and flower buds at flowering and boll-forming stages, five growth stages of untreated and treated roots with plant growth retardant. The best-suited RGs were accessed using ge Norm, NormF inder, Best Keeper, and Ref Finder algorithms. Results The best-ranked references genes differed across the samples. GAPDH and PP2A were the most suitable for expression analysis in untreated tissues while GAPDH, α-TUB, and PP2A were ranked as the three most stably expressed genes in untreated roots, while NAC and CYP were the most stably expressed genes in stressed（i.e., treated） roots. The expression of UGPase, a key enzyme for CPP biosynthesis, was determined to further validate the selected RGs. Conclusion A total of 10 RGs can be used as reference genes of C. pilosula, however the appropriate one should be used as it may chance.

关键词： Codonopsis pilosula normalization polysaccharide biosynthesis reference genes

Building the Crab pulsar timing model with XPNAV-1 observations

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Building the Crab pulsar timing model with XPNAV-1 observati...

Effect of Progressive Substitution of Cement and Lime by Powdered Shells Used as a Curing Agent for Dredged Soil in a Port Area

第九届中国卫星导航学术年会

作者： hai-feng sun Jian-yu Su Liang Zhao Zhi-wei Liu hai-yan Fang School of Aerospace Science and Technology Xidian University Science and Technology on Space Physics Laboratory Beijing Institute of Astronautical Systems Engineering

This paper addresses the problem of building the X-ray pulsar timing model that is an essential work for X-ray pulsar navigation(XNAV).We propose a theoretical discussion of the differences between the X-ray and radio pulsar timing and develop a complete processing *** this framework,the 2 mZ-test method is deduced by the theory of the Fourier Series Estimator(FSE) in the complex form.A fast maximum likelihood(FAML) estimator is applied for the estimation of pulse time of arrival(TOA).Then the model parameters are deduced based on a least-squares *** sustain this framework,about 173 ks observations with X-ray pulsar navigation-I(XPNAV-1) satellite over 30 days are utilized for experimental *** results show that the proposed framework is valid,and the phase residuals with the X-ray model parameters is 2.57 milliperiods.

关键词： X-ray pulsar navigation X-ray timing model Crab pulsar XPNAV-1 satellite

来源： cnki会议评论

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 88-102页

作者： sun Yang WANG Faxin SU Yaying LI Yiwei HE feng College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Huai'an Research Institute Hohai UniversityHuai'an 223025China Jiangsu Fangyang Industrial Investment Corp.Ltd. Lianyungang 210098China

This study aimed to address the challenges of solid waste utilization,cost reduction,and carbon reduction in the treatment of deep-dredged soil at Xuwei Port in Lianyungang city of *** research in this area was ***,a curing agent made from powdered shells was used to solidify the dredged soil in *** employed laboratory orthogonal tests to investigate the physical and mechanical properties of the powdered shell-based curing *** was collected by conducting experiments to assess the role of powdered shells in the curing process and to determine the optimal ratios of powdered shells to solidified soil for different *** development of strength in solidified soil was studied in both seawater and pure water *** study revealed that the strength of the solidified soil was influenced by the substitution rate of powdered shells and their interaction with *** cement content had a positive effect on *** high-strength solidified soil,the recommended ratio of wet soil:cement:lime:powdered shells were 100:16:4:4,while for low-strength solidified soil,the recommended ratio was 100:5.4:2.4:***,under appropriate conditions,improved short-term strength by promoting the formation of expansive ettringite minerals that contributed to cementation and *** findings suggest that the combination of cement and powdered shells is synergistic,positively affecting the strength of solidified *** recommended ratios provide practical guidance for achieving desired strength levels while considering factors such as cost and carbon *** role of seawater in enhancing short-term strength through crystal formation is noteworthy and can be advantageous for certain *** conclusion,this research demonstrates the potential of using a powdered shell-based curing agent for solidifying dredged soil in an environmentally friendly and cost-effective *** recommended ratios for different str

关键词： carbon reduction and solidification dredged soil abandoned shells orthogonal test chemical additives(lime and cement) unconfined compressive strength(UCS)