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The Impact of Nova Outbursts on the Chemical Abundance of the Interstellar Medium

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Research in Astronomy and Astrophysics 2024年第10期24卷 116-129页

作者： guoli He Chunhua Zhu guoliang Lü Lin Li Sufen Guo Helei {2. Jun Gao School of Physical Science and Technology Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

Nova outbursts are the results of thermonuclear runaways,which occur when sufficient material accretes on the surfaces of white dwarfs(WDs).Using the MESA code,we construct a detailed grid for carbon-oxygen and oxygen-neon-magnesium *** employing population synthesis methods,we conduct a statistical analysis of the distribution of novae in the Milky *** our models,on average,a typical nova system may undergo about8000 eruptions and the Galactic nova rate is~1.0 yr^(-1..The C,N,and O elements in nova ejecta are strongly affected by the mixing degree between WD core and accreted *** results show that the average value of^(1.0}C/^(1.)C in nova ejecta is about an order of magnitude lower than that on the surface of a red giant,that for^(1.)O/^(1.)O is about 5 times lower,and that for^(1.)N/^(1.)N is about 1.5 times *** annual yields of^(1.)C,^(1.)N,and^(1.)O from nova ejection are larger than those from AGB *** indicates that compared to a red giant,nova eruptions are a more important source of the odd-numbered nuclear elements of^(1.)C,^(1.)N,and^(1.)O in the Galactic interstellar medium.

关键词： ISM:abundances (stars:)novae cataclysmic variables (stars:)white dwarfs

Compliant Iontronic Triboelectric Gels with Phase-Locked Structure Enabled by Competitive Hydrogen Bonding

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Nano-Micro Letters 2024年第9期16卷 180-194页

作者： guoli Du Yuzheng Shao Bin Luo Tao {1. Jiamin Zhao Ying Qin Jinlong Wang Song Zhang Mingchao Chi Cong Gao Yanhua {1. Chenchen Cai Shuangfei Wang Shuangxi Nie School of Light Industry and Food Engineering Guangxi UniversityNanning 530004People’s Republic of China

Rapid advancements in flexible electronics technology propel soft tactile sensing devices toward high-level biointegration,even attaining tactile perception capabilities surpassing human ***,the inherent mechanical mismatch resulting from deficient biomimetic mechanical properties of sensing materials poses a challenge to the application of wearable tactile sensing devices in human-machine *** by the innate biphasic structure of human subcutaneous tissue,this study discloses a skin-compliant wearable iontronic triboelectric gel via phase separation induced by competitive hydrogen ***-nonsolvent interactions are used to construct competitive hydrogen bonding systems to trigger phase separation,and the resulting soft-hard alternating phase-locked structure confers the iontronic triboelectric gel with Young’s modulus(6.8-2.1.9 kPa)and high tensile properties(880%)compatible with human *** abundance of reactive hydroxyl groups gives the gel excellent tribopositive and self-adhesive properties(peel strength>70 N m^(−1.).The self-powered tactile sensing skin based on this gel maintains favorable interface and mechanical stability with the working object,which greatly ensures the high fidelity and reliability of soft tactile sensing *** strategy,enabling skin-compliant design and broad dynamic tunability of the mechanical properties of sensing materials,presents a universal platform for broad applications from soft robots to wearable electronics.

关键词： Triboelectric nanogenerator Cellulose Triboelectric gel Self-powered sensor Energy harvesting

Tribological Properties of SiC/Cu Composite at High Temperature

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Journal of Wuhan university of Technology(Materials Science) 2009年第6期24卷 888-891页

作者：范冰冰张锐 zhengzhou Institute of Aeronautical Industry Management School of Materials Science & Engineering Zhengzhou University

SiC/Cu composites were prepared by hot pressing. The high temperature tribological properties of the composites were investigated. XRD, SEM techniques were carried out to characterize the samples. It is found that the friction coefficient of SiC/Cu composites increases with the increasing SiC content. The SiC reinforcement particles are worn down other than removed by pulling out during the wear test. Oxidation of Cu debris leads to the smooth contacting surface. Ring crack is formed under the cyclic wear test. The crack propagates through the damaged matrix and along the brittle interface between SiC particles and Cu matrix.

关键词： SiC/Cu composite tribological properties high temperature wear ring crack

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1. ZHAO Weijuan1. LI Rongwu2. SUN Hongwei1. GUO Min1. WANG Yanfang1. {1. Hui1. ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical Engineering, zhengzhou university, {2. 450052. china 2. Department of Physics, Beijing Normal university, Beijing 1.0875, china 3. Institute of Cultural Relic and Archaeology of Henan Province, {2. 450000, china 4. Institute of Modern Physics, Fudan university, Shanghai 2.0433, china Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of Physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern Physics Fudan University Shanghai 200433 China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological Sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1. liu Changming1.{1. WANG Yu3 & WANG Hongrui1.1. Beijing Normal university, Beijing 1.0875, {{1. {1. Institute of Geographic Science and Natural Resources, Chinese Academy of Sciences, Beijing 1.01.1. {{1. 3. Reconnaissance, Planning, Design and Research Institute, YRCC, zhengzhou 450003, {{1. Beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1. When temperature is steady, the average annual runoff will increase by 8.3% if precipitation increases by 1.%; when precipitation decreases by 1.%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1.; if temperature decreases 1., runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1. and precipitation decreases by 1.%. Under this condition, the simulated average annual runoff decreases by 1..8%. On the contrary, scenario 1.is the best to the enhancement of runoff; i.e. when temperature decreases 1.℃ precipitation will increase by 1.%, which will make the annual runoff of Sanmenxia increase by 1..6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Effect of Cooling Rate on the Microstructure of ZA48 Alloy

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Journal of Wuhan university of Technology(Materials Science) 2010年第5期25卷 811-813页

作者：王杰芳谢敬佩 School of Physics and Engineering The Key Laboratory of Material Physics of the Ministry of Education of China Zhengzhou University The College of Materials Science & Engineering Henan University of Science and Technology

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate （about 40 to 1.^3 K/s） was determined by the secondary dendrite arm space size measurement, optical microscopy（OM）, and transmission electron microscopy （TEM）. It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid （α＋η）, the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn3Mg2.phase.

关键词： cooling rate microstructure secondary dendrite arm space size precipitation

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science china(Technological Sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1. ZHENG Hongxing1. liu Changming1. , WU Xianfeng{1.{1.& ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. china {1. Institute of Environmental Science, Beijing Normal {{1., Beijing 1.0875, china 3. Water Resources Conservation Committee of Yellow River, zhengzhou 450003, china Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1.96 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Effect of Post-spinning Modification on the PAN Precursors and Resulting Carbon Fibers

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Journal of Wuhan university of Technology(Materials Science) 2006年第3期21卷 44-48页

作者：张旺玺 Department of Mechanics Engineering Zhongyuan Institute of TechnologyZhengzhou 450070China

The impregnation of a special grade PAN precursor,fibers wus carried out in a 8 wt% KMnO4 aqueous solution to obtain modified PAN precursor fibers. The effects of modification on the chemical stncture and the mechanical properties of precursor fibers thermally stabilized and their resulting carbon fibers u＇ere characterized by the combiination use of densities, wide-angle X-ray diffraction （WAXD）, X-ray photoelectron speetroscopy （XPS）, elemental analysis （ EA ）, Fourier traasform infrared spectroscopy （FT-IR） and scanning electron microscope （SEM）, ***4 as a strong oxidizer can swell, oxidize and corrode the skin of a ***, and transform C≡N groups to C≡N ones, meamchile , it can decreuse the crystal .size increuse the orientation index and the costallinity index, furthermore it can increuse the densities of modified PAN precursors and resuhing thermally stabilized fibers. As a result, the carbon fibers developed from modified PAN fibers show an improvement in tensile strength of 31.2. % and an improvement in elongation of 77.78 % , but a decrease of 1.. 52. in Young＇s modulus.

关键词： carbon fibers carbon precursor chemical treatment mechanical properties

Image universal steganalysis based on best wavelet packet decomposition

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Science china(Information Sciences) 2010年第3期53卷 634-647页

作者： LUO XiangYang1.2. {1. FenLin1. YANG ChunFang1.& WANG DaoShun2.1.nformation Science and Technology Institute, zhengzhou 450002. {2. 2.epartment of Computer Science and Technology, Tsinghua university, Beijing 1.0084, {2. 1. Information Science and Technology Institute Zhengzhou 450002 China2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Based on the best wavelet packet decomposition of images, a new universal steganalysis method with high detection correct ratio is proposed. First, the best wavelet packet decomposition of image based on the Shannon entropy information cost function is made. Second, high order absolute characteristic function moments of histogram extracted from the coefficient subbands obtained by best wavelet packet decomposition are regarded as features. Finally, these features are processed and a back-propagation (BP) neural network is designed to classify original and stego images. Three different steganalysis algorithms for three different cases of background and application condition are presented. To validate the performance of the proposed method, a series of experiments are made for six kinds of typical steganography methods, i.e. LSB, LTSB, PMK, Jsteg, F5 and JPHide. Results show that, the average detection accuracy of the proposed method exceeds at least 6.4% and up to 1..4% and has a better universal performance than its closest competitors. Furthermore, the proposed method can provide reference for designing the pattern recognition and classification algorithm based on best wavelet packet decomposition.

关键词： steganography digital images universal steganalysis best wavelet packet decomposition BP neural network