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Chinese Chemical Letters 2003年第1期14卷 20-21页

作者： Shu Ling GONG Wei WANG peng fei fang Yuan Yin CHEN College of Chemistry and Molecular Science Wuhan UniversityWuhan 430072

Nano CaCO3 was used as a condensation agent in the ring-opening reaction of p-tert-butylcalix[4]arene with epichlorohydrin to afford 5,11,17,23-tetra-tert-butyl-26,27,28-trihyd- roxy-25-(1-chloro-2-hydroxy-3-propyl)calix[4]arene regioselectively in 52% yield. The yield was less than 2% by using normal CaCO3 instead of nano one under the same conditions.

关键词： Nano CaCO_3 epoxide calixarene monofunctionalization.

Neural-mechanism-driven image block encryption algorithm incorporating a hyperchaotic system and cloud model

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Chinese Physics B 2022年第4期31卷 175-190页

作者： peng-fei fang Han Liu Cheng-Mao Wu Min Liu School of Automation and Information Engineering Xi’an University of TechnologyXi’an 710048China School of Electronic Engineering Xi’an University of Posts&TelecommunicationsXi’an 710061China School of Engineering and Computer Science Australian National UniversityCanberra 0200Australia

An image encryption algorithm is proposed in this paper based on a new four-dimensional hyperchaotic system,a neural mechanism,a Galois field and an improved feistel block structure,which improves the efficiency and enhances the security of the encryption ***,a four-dimensional hyperchaotic system with a large key space and chaotic dynamics performance is proposed and combined with a cloud model,in which a more complex and random sequence is constructed as the key stream,and the problem of chaotic periodicity is ***,the key stream is combined with the neural mechanism,Galois field and improved feistel block structure to scramble and diffuse the image ***,the experimental results and security analysis show that the encryption algorithm has a good encryption effect and high encryption efficiency,is secure,and can meet the requirements of practical applications.

关键词： image encryption neural mechanism hyperchaotic system

Fullerene bisadduct stabilizers:The effect of different addition positions on inhibiting the autocatalytic decomposition of nitrocellulose absorbed nitroglycerin

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Defence Technology（防务技术） 2021年第6期17卷 1944-1953页

作者： Ling Liao Bo Jin Zhi-cheng Guo fei Xian Chen-jie Hou Ru-fang peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologySichuanMianyang621010China

To explore the effect of different positions and number of pyrrolidine bound to the carbon cage on the stabilization effect of fulleropyrrolidine derivatives to nitrocellulose(NC)/nitroglycerine(NG),we synthesized N-(4-methoxy)phenylpyrrolidine-C_(60) and four different of bis(N-(4-methoxy)phenylpyrrolidine)-C_(60) compounds through Prato *** structures were characterized by UVevis,^(1)H NMR,^(13)C NMR,high-resolution mass spectroscopy,and single-crystal X-ray *** stabilization effect to NC/NG were investigated using differential scanning calorimetry,methyl violet,vacuum stabilization effect,weight loss,and accelerating rate calorimeter *** results indicated these compounds had excellent stabilization effect to NC/*** stabilization effect of the fulleropyrrolidine bisadducts to NC/NG is significantly better than that of fulleropyrrolidine monoadduct and C_(60).Moreover,the position where pyrrolidine binds to fullerene in fulleropyrrolidine bisadducts is different,and its stabilization effect to NC is also *** stabilization effect order of different bisadduct isomers to nitrocellulose is as follows:e-edge>trans-2>cis-2>*** paramagnetic resonance(EPR)and FT-IR were used to study the stabilization mechanism of fulleropyrrolidine derivatives to NC/*** EPR results also show that fulleropyrrolidine bisadducts with different addition sites have different abilities to absorb nitroxide,and their ability is better than that of the monoadduct and C_(60),which is consistent with the results of stabilization effect performance test.

关键词： Fulleropyrrolidine bisadducts Stabilization effect Nitrocellulose/nitroglycerine

Impacts of the north migration of China＇s rice production on its ecosystem service value during the last three decades (1980-2014)

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Journal of Integrative Agriculture 2017年第1期16卷 76-84页

作者： fang Fu-ping FENG Jin-fei LI Feng-bo peng Shao-bing Huazhong Agricultural University Wuhan 430070 P.R. China China National Rice Research Institute Hangzhou 310006 P.R. China

The ecosystem services value （ESV） of rice system has received increasing attention in agricultural policy decision. Over the last three decades, China＇s rice production presented an obviously trend that moving towards north locations. However, the impacts of this migration on the ESV of rice production have not been well documented. In this paper, we analyzed the change of the ESV of rice production in China under ＂north migration＂ and ＂no migration＂ scenarios during 1980-2014 based on long-term historical data. The results showed that both the positive and negative ESVs of rice production were lower under ＂north migration＂ than under ＂no migration＂ scenarios. The total ESV during 1980-2014 was reduced by 15.8%. ＂North migration＂ significantly reduced the area-scaled ESV since the early 1990s; while its impact on yield-scaled ESV was not significant. The effects of＂north migration＂ on ESV showed great spatial variation. The greatest reduction in total and area-scaled ESV was observed in south locations. While the yield-scaled ESVs of most south locations were enhanced under ＂north migration＂ scenario. These results indicated that ＂north migration＂ has generated adverse effects on the ESV of rice production. An adjustment in the spatial distribution is essential to protecting the non-production benefits of rice ecosystem.

关键词： ecosystem service value north migration rice ecosystem spatial variation historical change

Can we determine the filament chirality by the filament footpoint location or the barb-bearing？

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Research in Astronomy and Astrophysics 2016年第1期16卷 1-12页

作者： Qi Hao Yang Guo Cheng fang peng-fei Chen Wen-Da Cao School of Astronomy and Space Science Nanjing University Nanjing 210023 China Key Laboratory for Modern-Astronomy and Astrophysics (Nanjing University) Ministry of Education Nanjing 210023 China New Jersey Institute of Technology Center for Solar Research 323 Martin Luther King Blvd. Newark NJ 07102-1982 U.S.A. Big Bear Solar Observatory 40386 North Shore Lane Big Bear City CA 92314-9672 U.S.A.

We attempt to propose a method for automatically detecting the solar filament chirality and barb beating. We first introduce the concept of an unweighted undirected graph and adopt the Dijkstra shortest path algorithm to recognize the filament spine. Then, we use the polarity inversion line （PIL） shift method for measuring the polarities on both sides of the filament, and employ the connected components labeling method to identify the barbs and calculate the angle between each barb and the spine to determine the bearing of the barbs, i.e., left or right. We test the automatic detection method with Ha filtergrams from the Big Bear Solar Observatory （BBSO） Ha archive and magnetograms observed with the Helioseismic and Magnetic Imager （HMI） on board the Solar Dynamics Observatory （SDO）. Four filaments are automatically detected and illustrated to show the results. The barbs in different parts of a filament may have opposite bearings. The filaments in the southern hemisphere （northern hemisphere） mainly have left-bearing （fight- bearing） barbs and positive （negative） magnetic helicity, respectively. The tested results demonstrate that our method is efficient and effective in detecting the bearing of filament barbs. It is demonstrated that the conventionally believed one-to-one correspondence between filament chirality and barb bearing is not valid. The correct detection of the filament axis chirality should be done by combining both imaging morphology and magnetic field observations.

关键词： Sun: filaments prominences -- Sun: magnetic fields -- Sun: chromosphere -- techniquesimage processing

Diagnosis of disease-specific proteins in cerebrospinal fluid of children infected with tuberculous meningitis

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Neural Regeneration Research 2010年第12期5卷 927-932页

作者： Jing peng Hongyuan Zhang Liwen Wu fang He fei Yin Department of Pediatrics Xiangya Hospital Central South University Changsha 410008 Hunan Province China

BACKGROUND： Isolated mycobacterium tuberculosis from cerebrospinal fluid （CSF） is regarded as the ＂gold standard＂ for diagnosis of tuberculous meningitis （TBM）. However, culture of CSF specimens is time-consuming and lacks sensitivity. There is a strong need to determine complementary disease-specific markers, which are essential for increasing early diagnosis and improving prognosis in patients with TBM OBJECTIVE： To establish proteomic profiles of CSF in TBM and normal children using two-dimensional polyacrylamide gel electrophoresis, and to screen for disease-specific proteins. DESIGN, TIME AND SETTING： The case-control study was conducted at the Department of Pediatrics, Xiangya Hospital of Central South University and the Key Laboratory of Cancer Proteomics of Ministry of Public Health of China between January 2008 and January 2009. PARTICIPANTS： The TBM group included three patients with a strongly positive tuberculin skin test, as well as positive CSF mycobacterial staining and culture, who were admitted to the Department of Pediatrics, Xiangya Hospital from January 2008 to January 2009. Three healthy, age- and gender-matched children served as the control group. METHODS： CSF proteins were separated using two-dimensional polyacrylamide gel electrophoresis in both groups. Gels were scanned using Image scanner and LabScan software. Differentially expressed proteins were analyzed using PDQuest 7.0 software. The clearly discernible spots, which were expressed only in the TBM group, were chosen to perform matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. MAIN OUTCOME MEASURES： Differentially expressed spots on CSF profiles of TBM and normal children were measured. RESULTS： Following comparison of two-dimensional polyacrylamide gel electrophoresis maps between TBM and control groups, 546 and 533 spots were detected, respectively. A total of 64 differentially expressed proteins were observed between the groups, including 15 upreg

关键词： tuberculosis meningitis proteomics children cerebrospinal fluid two-dimensional polyacrylamide gel electrophoresis neural regeneration

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机械刺激信号对椎间盘细胞影响的研究进展

临床骨科杂志 2015年第6期18卷 748-751页

作者：张德宏方鹏飞王兴盛赵继荣甘肃省中医院脊柱骨科甘肃兰州730050 甘肃省中医院白银分院骨科甘肃白银730900

机械刺激对维持椎间盘及其基质的正常代谢具有重要作用,主要通过直接或间接刺激椎间盘细胞影响椎间盘细胞的增殖、分化、凋亡、生物基质的分泌等,从而维持整个椎间盘的代谢平衡。近年来,机械刺激,尤其是轴向负荷及流体力刺激如何改变椎... 详细信息

机械刺激对维持椎间盘及其基质的正常代谢具有重要作用,主要通过直接或间接刺激椎间盘细胞影响椎间盘细胞的增殖、分化、凋亡、生物基质的分泌等,从而维持整个椎间盘的代谢平衡。近年来,机械刺激,尤其是轴向负荷及流体力刺激如何改变椎间盘细胞生物化学功能的问题,逐渐成为研究热点。该文对轴向负荷和流体力等机械信号刺激椎间盘细胞的应答机制、以及机械刺激对椎间盘退化的影响和椎间盘退化的生物学治疗方法进行综述。

关键词：椎间盘细胞机械刺激椎间盘退化轴向负荷流体力刺激

The Time-Dependent Von Kármán Shell Equation as a Limit of Three-Dimensional Nonlinear Elasticity

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Journal of Systems Science & Complexity 2021年第2期34卷 465-482页

作者： QIN Yizhao YAO peng-fei Department of Mathematical Science Tsinghua UniversityBeijing 100084China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

The asymptotic behaviour of solutions of three-dimensional nonlinear elastodynamics in a thin shell is considered,as the thickness h of the shell tends to *** the appropriate scalings of the applied force and of the initial data in terms of h,it’s verified that three-dimesional solutions of the nonlinear elastodynamic equations converge to solutions of the time-dependent von Kármán equations or dynamic linear equations for shell of arbitrary geometry.

关键词： Nonlinear elasticity thin shell time-dependent von Kármán equations

The Uniqueness of Knieper Measure on Non-compact Rank 1 Manifolds of Non-positive Curvature

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Acta Mathematica Sinica,English Series 2021年第8期37卷 1219-1228页

作者： fei LIU fang WANG College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590P.R.China School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

We study the Knieper measures of the geodesic flows on non-compact rank 1 manifolds of non-positive *** construct the Busemann density on the ideal boundary,and prove that if there is a Knieper measure on T^(1)M with finite total mass,then the Knieper measure is unique,up to a scalar *** result partially extends Paulin-Pollicott-Shapira’s work on the uniqueness of finite Gibbs measure of geodesic flows on negatively curved non-compact manifolds to non-compact manifolds of non-positive curvature.

关键词： Geodesic flows Patterson-Sullivan measure Knieper measure

The Hot Spots Conjecture on a Class of Domains in R^n with n≥3

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 639-646页

作者： peng-fei YANG School of Science Beijing Institute of Technology Beijing 100081 China

In this paper, we define a class of domains in R^n. Using the synchronous coupling of reflecting Brownian motion, we obtain the monotonicity property of the solution of the heat equation with the Neumann boundary cond... 详细信息

关键词： synchronous coupling reflecting Brownian motion hot spots conjecture Neumann eigenfunctions