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Hermitian Adjacency Spectrum of Cayley Digraphs over Dihedral Group

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Algebra Colloquium 2020年第1期27卷 121-130页

作者： Honghai Li teng yu College of Mathematics and Information Science Jiangxi Normal University Nanchang 330022China

We first study the spectrum of Hermitian adjacency matrix(H-spectrum)of Cayley digraphs X(D 2n,S)on dihedral group D2n with|S|=*** we show that all Cayley digraphs X(D2P,S)with|S|=3 and p odd prime are Cay-DS,namely,f... 详细信息

关键词： digraph dihedral group Hermitian adjacency matrix Cay-DS 3-DCI property

Detecting changes in long-period site responses after the M_w 7.6 Chi-Chi earthquake, Taiwan, using strong motion records

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 217-228页

作者： teng-To yu Chi-Shin Wu Youg-Sin Cheng Department of Resources Engineering Cheng Kung University (NCKU)

Temporal changes in site effects are obtained using the HVSR(horizontal-to-vertical spectral ratio) method and strong motion records after the M w 7.6 Chi-Chi earthquake, Taiwan. Seismic data recorded between 1995 and 2010 are used, comprising 3,708 data from 15 stations adjacent to the Chelungpu fault. Temporal fl uctuations are determined by analyzing the site effect variation using a time–frequency variation(TFV) diagram based on these seismic data. Stations adjacent to the fault show signifi cant disturbances in the resonance frequency at 16–26 Hz. Station TCU129 shows a 40% drop in fundamental frequency after the main shock, and a gradual return to the original state over nine years. For stations located farther from the fault zone, sudden changes in tectonic stress play a dominant role in temporal changes to the HVSR. An impact analysis of the directional factor confi rms our fi nding that the proximity of the fault to seismic stations has the most infl uence on data.

关键词： Chi-Chi earthquake horizontal-to-vertical spectral

Degeneracy and discreteness in cosmological model fitting

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Research in Astronomy and Astrophysics 2016年第3期16卷 121-128页

作者： Huan-yu teng yuan Huang Tong-Jie Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Departments of Physics and Astronomy University of CaliforniaBerkeleyCA 94720USA Lawrence Berkeley National Laboratory 1 Cyclotron RoadBerkeleyCA 94720USA

We explore the problems of degeneracy and discreteness in the standard cosmological model（ΛCDM）. We use the Observational Hubble Data（OHD） and the type Ia supernovae（SNe Ia） data to study this issue. In order to describe the discreteness in fitting of data, we define a factor G to test the influence from each single data point and analyze the goodness of G. Our results indicate that a higher absolute value of G shows a better capability of distinguishing models, which means the parameters are restricted into smaller confidence intervals with a larger figure of merit evaluation. Consequently, we claim that the factor G is an effective way of model differentiation when using different models to fit the observational data.

关键词： cosmological parameters -- cosmology: observations -- methods: statistical

Characteristics of long period microtremor and validation of microtremor array measurements in inland areas of China

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Journal of Mountain Science 2016年第11期13卷 1910-1922页

作者： CHE Ai-lan ZHANG teng-yu FENG Shao-kong School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University 800 Dongchuan-Road Shanghai 200240 China

To study the characteristics of long period microtremor and applicability of microtremor survey,we have made microtremor observations using long period seismometers of the China's mainland from coastal cities like Shanghai and Tianjin through Beijing,Xi'an,to the far inland cities of Lanzhou and *** observation shows that the level of power spectrum of long period microtremors reduced rapidly from the coast to the inland ***,the energy of long period microtremors in Beijing,Xi'an,Lanzhou and Tianshui area are only approximately ten-thousandth to thousandth of that in *** at the complexity of the underground structure in the far inland,a series of underground structure models with different distributions were assessed using three-dimensional,dynamic finite element method(FEM) *** results were used to evaluate microtremor survey methods and their limitations with regard to aggregate variability and thickness ***-wave reflections between layers with the change of underground structure distribution occurred,which have significant effect on the performance of the different field *** over a broad spectrum from which velocity-depth profiles were produced via inversion *** the thickness nor the shear waveVelocity V of the subsurface layer inversion results appeared over a large evaluation with increasing slope *** particular,when the angle of the model reached 45°,it could not be accurately evaluated using one-dimensional inversion ***,the array microtremor survey(AMS) was carried out in Shanghai City,*** AMS techniques do not have the layer sensitivity or accuracy(velocity and layer thickness) of borehole techniques,the obtained shear wave velocity structure is especially useful for earthquake disaster prevention and seismic analysis.

关键词： Long period microtremor Array Microtremor survey Power spectrum Inversion S-wave velocity structure

A new drug carrier:Magnetite nanoparticles coated with amphiphilic block copolymer

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Chinese Science Bulletin 2009年第7期54卷 1190-1196页

作者： CHANG yu BAI yunPeng teng Bao LiZhaoLong Department of Chemistry Tsinghua University Beijing 100084 China

This paper reports on the synthesis and characterization of 4 nm magnetite nanoparticles coated with amphiphilic block copolymers of poly(ethyl methacrylate)-b-poly(2-hydroxyethyl methacrylate) (PEMA- b-PHEMA) by surface-initiated atom transfer radical polymerization (ATRP), which can act as new potential carriers for hydrophobic targeted drug delivery. Vibrating sample magnetometer analysis indi-cated that the magnetite nanoparticles were superparamagnetic at room temperature. Thermogravim-etric analysis (TGA) was applied to studying the property of surface of magnetite nanoparticles, and the surface density of macromolecules was calculated. The grafting density of oleic acid, BrMPA and PEMA was 5.8, 3.9, 0.16 chain/nm2 respectively, which indicates that the initiation efficiency decreases due to the influence of large space of oleic acid molecules. In vitro progesterone and (-)-isoproterenol hy-drochloride release in phosphate buffered saline (PBS) at pH 7.0 and 37℃ was conducted in order to demonstrate the function of drug loading and release. The results showed that the amount of drug carried into the core-shell Fe3O4@PEMA-b-PHEMA depends on the length of hydrophobic segment of block copolymer. The release of progesterone (37% after 22 h in our previous work) was compared with the release of (-)-isoproterenol hydrochloride (80% after 50 min), demonstrating that the strong hy-drophobic interaction between hydrophobic segment and drug can effectively control the release of hydrophobic drugs.

关键词：双亲嵌段共聚物纳米涂层药物载体磁铁矿原子转移自由基聚合甲基丙烯酸乙酯盐酸异丙肾上腺素磁性纳米粒子

Hot cracking behavior of large size GH4742 superalloy vacuum induction melting ingot

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Journal of Iron and Steel Research International 2022年第9期29卷 1505-1512页

作者： Liang Zhang Lei Wang Yang Liu Xiu Song teng yu Ran Duan Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationSchool of Materials Science and EngineeringNortheasternUniversityShenyang 110819LiaoningChina High Temperature Materials Division Fushun Special Steel Co.Ltd.Fushun 113001LiaoningChina Gaona Aero Material Co. Ltd.Beijing 100081China

The developing of large size superalloy vacuum induction melting(VIM)ingots is limited owing to hot cracking,The hot cracking behavior of the large size GH4742 superalloy VIM ingot was investigated via experiment and *** microstructure was examined by optical microscopy,and element segregation was investigated by electron probe *** solidification temperature range and yield strength at high temperature(YSHT)were calculated by JMatPro *** results show that the variations of microstructure and element segregation in different locations are caused by different cooling ***,the larger secondary dendrite arm spacing and serious element segregation of Nb accelerate hot cracking of the VIM *** addition,the solidification temperature range is wider,and YSHT is lower in center than at edge of the ***,the hot cracking susceptibility is the highest in the center of the GH4742 superalloy VIM *** critical criterion of element segregation for hot cracking is that the partition coeffcient of Nb should be larger than 0.5.

关键词： Hot cracking Large size-Superlloy Vacuum induction melting ingot Element segregation

Recent advances in catalytica symmetric Buchner reaction

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Chinese Chemical Letters 2023年第12期34卷 87-92页

作者： Chong-Yang Shi Guang-yu Zhu Yin Xu Ming-yu teng Long-Wu Ye College of Chemistry and Chemical Engineering Yunnan Normal UniversityKunming 650500China Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid Surfacesand College of Chemistry and Chemical EngineeringXiamenUniversity.Xiamen361005China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic *** the asymmetric version has been investigated since the early 1990s,enantioselective Bichner reaction is still limited by the catalyst type and substrate *** review aims to propose the limitation and possible development direction of this field by summarizing the evolution of catalytic asymmetric Bichner reaction,which is organized on the basis of intra-and intermolecular *** the different metal carbene precursors,the reactions are further classified by carbene sources.

关键词： Bichner reaction Diazo compounds Metal carbenes Cycloheptatrienes Dearomatization reactions

IDV:Internet Domain Name Verification Based on Blockchain

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Computer Modeling in Engineering & Sciences 2021年第10期129卷 299-322页

作者： Ning Hu yu teng Yan Zhao Shi Yin yue Zhao Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Zhong Zi Hua Ke Traffic Construction Technology Co. Ltd.Beijing100195China Science and Technology on Communication Security Laboratory Chengdu610041China

The rapid development of blockchain technology has provided new ideas for network security ***-based network security enhancement solutions are attracting widespread *** paper proposes an Internet domain name verification method based on *** authenticity of DNS(Domain Name System)resolution results is crucial for ensuring the accessibility of Internet *** to the lack of adequate security mechanisms,it has always been a challenge to verify the authenticity of Internet domain name resolution *** the solution represented by DNSSEC(Domain Name System Security Extensions)can theoretically solve the domain name verification problem,it has not been widely deployed on a global scale due to political,economic,and technical *** argue that the root cause of this problem lies in the significant centralization of the DNS *** centralized feature not only reduces the efficiency of domain name verification but also has the hidden risks of single point of failure and unilateral *** users may disappear from the Internet due to the results of fake,subverted,or misconfigured domain name *** paper presents a decentralized DNS cache verification method,which uses the consortium blockchain to replace the root domain name server to verify the authenticity of the domain *** with DNSSEC’s domain name verification process,the verification efficiency of this method has increased by 30%,and there is no single point of failure or unilateral control *** addition,this solution is incrementally deployable,and even if it is deployed on a small number of content delivery network servers,satisfactory results can be obtained.

关键词： Blockchain-based network security DNS security DNS decentralization CDN

A general strategy for in situ assembly of light-up fluorophores via bioorthogonal Suzuki-Miyaura cross-coupling

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Chinese Chemical Letters 2022年第9期33卷 4223-4228页

作者： Xiang Li Hong Yang yu teng Yongcheng Wang Dali Yin yulin Tian Key Laboratory of Bioactive Substances and Function of Natural Medicine Beijing Key Laboratory of Active Substances Discovery and Drugability EvaluationInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Herein we presented a general strategy for in situ assembly of intramolecular charge-transfer(ICT)-based light-up fluorophores via bioorthogonal Suzuki-Miyaura cross-coupling *** introducing iodo group at the appropriate position,five fluorophores with different scaffolds including naphthalimide,coumarin,naphthalene sulfonate,nitrobenzoxadiazole,and acetonaphthone,were designed as bioorthogonal multicolor fluorogenic probes,which could produce significant fluorescence enhancement and high fluorescence quantum yield after Suzuki-Miyaura reaction with aryl boronic acid or *** the substituents andπscaffold in the fluorophores allows fine-tuning of their photophysical *** this strategy,we succeeded in peptide conjugation,no-wash fluorogenic protein labeling,and mitochondria-selective bioorthogonal imaging in live cells.

关键词： Bioorthogonal reaction Suzuki-Miyaura cross-coupling Fluorogenic probes Naphthalimide Live-cell imaging