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Ingredients-based Methodology and Fuzzy Logic Combined Short-Duration Heavy Rainfall Short-Range Forecasting:An Improved Scheme
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作者 TIAN Fu-you XIA Kun +2 位作者 SUN Jian-hua ZHENG Yong-guang HUA Shan 《Journal of Tropical Meteorology》 SCIE 2024年第3期241-256,共16页
Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the mos... Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the most common convective weather phenomena that can cause severe damage.Short-range forecasting of SHR is an important part of operational severe weather prediction.In the present study,an improved objective SHR forecasting scheme was developed by adopting the ingredients-based methodology and using the fuzzy logic approach.The 1.0°×1.0°National Centers for Environmental Prediction(NCEP)final analysis data and the ordinary rainfall(0.1-19.9 mm h-1)and SHR observational data from 411 stations were used in the improved scheme.The best lifted index,the total precipitable water,the 925 hPa specific humidity(Q 925),and the 925 hPa divergence(DIV 925)were selected as predictors based on objective analysis.Continuously distributed membership functions of predictors were obtained based on relative frequency analysis.The weights of predictors were also objectively determined.Experiments with a typhoon SHR case and a spring SHR case show that the main possible areas could be captured by the improved scheme.Verification of SHR forecasts within 96 hours with NCEP global forecasts 1.0°×1.0°data initiated at 08:00 Beijing Time during the warm seasons in 2015 show the results were improved from both deterministic and probabilistic perspectives.This study provides an objectively feasible choice for short-range guidance forecasts of SHR.The scheme can be applied to other convective phenomena. 展开更多
关键词 ingredients-based methodology fuzzy logic approach probability of short-duration heavy rainfall(SHR) improved forecasting scheme objectively obtained membership functions
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Obtaining Simply Explicit Form and New Properties of Euler Polynomials by Differential Calculus
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作者 Do Tan Si 《Applied Mathematics》 2023年第7期460-480,共21页
Utilization of the shift operator to represent Euler polynomials as polynomials of Appell type leads directly to its algebraic properties, its relations with powers sums;may be all its relations with Bernoulli polynom... Utilization of the shift operator to represent Euler polynomials as polynomials of Appell type leads directly to its algebraic properties, its relations with powers sums;may be all its relations with Bernoulli polynomials, Bernoulli numbers;its recurrence formulae and a very simple formula for calculating simultaneously Euler numbers and Euler polynomials. The expansions of Euler polynomials into Fourier series are also obtained;the formulae for obtaining all π<sup>m</sup> as series on k<sup>-m</sup> and for expanding functions into series of Euler polynomials. 展开更多
关键词 Obtaining Appell Type Euler Numbers and Polynomials Relations Euler-Bernoulli Polynomials Sums over km Series on k-m Euler Series of Functions
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Stability for the Manifold of Equilibrium State of the Autonomous Birkhoff System 被引量:3
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作者 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第2期106-109,共4页
Studies the stability for them manifold of equilibrium state of the autonomous Birkhoffsystem. Uses the Liapunov's direct method and the first approximation method to obtain thestability criterion for the manifold... Studies the stability for them manifold of equilibrium state of the autonomous Birkhoffsystem. Uses the Liapunov's direct method and the first approximation method to obtain thestability criterion for the manifold of equilibrium state of the system. Gives an example toillustrate the application of the result. 展开更多
关键词 analytical mechanics Birkhoff system stability In 1927 American mathematician Birkhoff GD obtained a kind of dynamical equationswhich were more general than the Hamilton's equations in his well -known work ' DynamicalSystems' [1] In 1978. American ph
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Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated Oxalates 被引量:24
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作者 M.I.El-Hofy(Physics Department, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt)A.M.Donia(Chemistry Department, Faculty of Science, Menoufia University, Shebin El-Kom, Egypt)M.M.Abou-Sekkina(Chemistry Department, Faculty of Science, Taota Un 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第1期87-90,共4页
Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of ann... Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of annealing time on the transport properties was studied. IR andX-ray spectra were also studied. 展开更多
关键词 CuO Figure Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated Oxalates
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Solid State Reaction Yielding a Mineral Utilizing Silica Obtained from an Agricultural Waste 被引量:5
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作者 M.S.Nizami M.K.Farooq K.Hussain and M.Z.Iqbal(PCSIR Laboratories Complex, Lahore, Pakistan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第3期276-280,共5页
Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to... Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to produce it through solid state reaction from 900℃ to 1300℃. The conducted reaction was monitored by XRD step by step. Amount of Wollastonite formed at every temperature was also studied to some extent. Analyses of the obtained data indicated that the target mineral formation was quite effective and almost proportional to a rise in temperature up to 1200℃. The results from both, XRD and chemical analysis were found in fair agreement with one another 展开更多
关键词 OO CAO Co Solid State Reaction Yielding a Mineral Utilizing Silica Obtained from an Agricultural Waste SIO
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The research on signal-obtaining pattern for a new type of gyroscope 被引量:8
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作者 Jian-feng Liu Gan-nan Yuan Lei Zhao and Shi-jun Zhao 《Journal of Marine Science and Application》 2003年第2期46-52,共7页
In this paper, a photoelectric signal obtained scheme via equator triangle pattern engraved on rotor is discussed and the mathematic model is deduced in the case which is deflexion between rotor axis and the coordinat... In this paper, a photoelectric signal obtained scheme via equator triangle pattern engraved on rotor is discussed and the mathematic model is deduced in the case which is deflexion between rotor axis and the coordinate frame of case. The deflexion error and coupling error under the situation are analyzed. Finally, three methods of engraving based on the spherical triangle pattern are presented. The error models of various methods are built up and the simulation curves are provided respectively. We have done the primary experiments on the surface of rotor using this method. It can be seen from the enlarged figures that the rim of the pattern is smooth and the demand of sensor resolution is satisfied by and large. The results of study supply reference for signal obtaining. 展开更多
关键词 The new type of gyro optical signal obtaining system: triangle pattern graving technology
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High Coercive NdFeB Thin Film Obtained by Diffusion Annealing 被引量:3
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作者 MJ.Kim and Y.B.Kim (Korea Research Institute of Standards and Science, Taejon 305-600, Korea) C.B.Song (Kongju National University, Kongju 314-701, Chungnam, Korea) Y.Li, D.S.Suhr, C.O.Kim and T.K.Kim (Chungnam National University, Taejon 305-340, Korea) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期111-112,共2页
The magnetic properties and microstructure of diffusion annealed [Ta/Nd/NdFeB/Nd/Ta]thin films have been investigated. The films were deposited on Si substrate with various thickness ratio of Nd/NdFeB layer (R=0~3.3)... The magnetic properties and microstructure of diffusion annealed [Ta/Nd/NdFeB/Nd/Ta]thin films have been investigated. The films were deposited on Si substrate with various thickness ratio of Nd/NdFeB layer (R=0~3.3), then diffused and crystallized by annealing at 650℃ for 10 min. The film without Nd layer showed soft magnetic behavior and high content of a-Fe phase. The films with R > =1 showed good hard magnetic properties with the high coercivity of about 20 kOe. 展开更多
关键词 THIN NDFEB High Coercive NdFeB Thin Film Obtained by Diffusion Annealing
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The Fourier Transform and Principles of Quantum Mechanics 被引量:2
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作者 Do Tan Si 《Applied Mathematics》 2018年第4期347-354,共8页
From the hypotheses that the position-representation of a physical state is the Fourier transform of its momentum-representation and that the timerepresentation is the inverse Fourier transform of its energy-represent... From the hypotheses that the position-representation of a physical state is the Fourier transform of its momentum-representation and that the timerepresentation is the inverse Fourier transform of its energy-representation, we are able to obtain the Planck relation E = hν , the de Broglie relation p = h /λ , the Dirac fundamental commutation relation, the Schr?dinger equations, the Heisenberg uncertainty principle in quantum mechanics, and the annihilation/creation of a photon from excitation/de-excitation of an atom following Bohr. 展开更多
关键词 Fourier Transform of BRA Obtaining DIRAC COMMUTATION Relation and PRINCIPLES of Quantum Mechanics
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Chinese Scientists Have Obtained Great Achievements in Comprehensive Research on the Qinghai-Tibet Plateau 被引量:1
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第2期629-630,共2页
The China Geological Survey carried out 1:250000 regional geological surveys of the Qinghai-Tibet Plateau from 1999 to 2005. With a total investment of 300 million yuan, more than 1000 geologists were involved annual... The China Geological Survey carried out 1:250000 regional geological surveys of the Qinghai-Tibet Plateau from 1999 to 2005. With a total investment of 300 million yuan, more than 1000 geologists were involved annually to conduct mapping at a grid of one line to every four km along the Kunlun Mts-Altyn Shan-Tanggula Shah, Kokoxili-Qiangtang, Gangdese, Yalun Zangbu River, and finally to the Himalayan ranges. The extensive mapping culminated in a total of 112 maps covering an area of 152 square kilometers. Based on this success, the China Geological Survey launched another program, the "Integration and Comprehensive Study of Basic Geological Survey Result(s) in the Qinghai-Tibet Plateau". The program lasted from 2006 to 2010 and has yielded copious research results, making big strides in upgrading our understanding of the Qinghai-Tibet Plateau. The achievements are manifold. Around 100 maps have been drafted, including the 1:1500000 geological map, tectonic, tectono-magmatic, metamorphic rocks, Precambrian geology, lithofacies palaeogeography, Cenozoic geology, geophysical-geochemical maps and others. 展开更多
关键词 Chinese Scientists Have Obtained Great Achievements in Comprehensive Research on the Qinghai-Tibet Plateau
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瑕疵证据与非法证据界分标准研究
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作者 王迎 曹红军 《安徽理工大学学报(社会科学版)》 2016年第1期39-43,共5页
刑事案件中以庭审为中心的实质在于以证据裁判为重心,而证据裁判的前提是构建非法证据和瑕疵证据的界分标准。因此,通过实证分析刑事证据情形常态分布,提出违法程度、证据的客观性和程序正义的界分标准。
关键词 DEFECTIVE EVIDENCE illegally obtained EVIDENCE the standard of CLASSIFICATION
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Captain's Paranoid Personality and Obtaining Principles in the Moby Dick
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作者 任跃强 王鼎 《海外英语》 2018年第19期194-196,共3页
Herman Melville(1819-1891) is one of the famous writers in the history of American and world literature. Moby Dick is one of the masterpieces of Melville, and it is also his most famous ocean works in his late life. M... Herman Melville(1819-1891) is one of the famous writers in the history of American and world literature. Moby Dick is one of the masterpieces of Melville, and it is also his most famous ocean works in his late life. Moby Dick describes a story on Captain Ahab took revenge on white whale. This paper will discuss Captain Ahab's paranoid personality, and reveal how Melville reflected in the works: coexistence between human and nature. A brief description will be provided for the writer's life and his works, and then I will discuss Captain Ahab's paranoid personality through his whaling capturing process. Then, I will discuss obtaining principles of Captain Ahab, Mate Starbuck, Crew Ishmael, and reveal the Captain's tragic causes and reflected thinking. Finally, I will make a conclusion only if people adopt right obtaining principles to natural resources, could we live with nature altogether. 展开更多
关键词 Moby DICK Herman MELVILLE PARANOID PERSONALITY Obtaining PRINCIPLES Tragedy
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Spatial Characteristics of Thomson Scattering Spectra in Laser and Magnetic Fields
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作者 Li Zhao Zhi-Jing Chen +1 位作者 Hai-Bo Sang Bai-Song Xie 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第7期34-38,共5页
Spatial characteristics of Thomson scattering spectra are studied for an electron moving in the circularly polarized laser field in the presence of a strong uniform magnetic field. The results show that the angular di... Spatial characteristics of Thomson scattering spectra are studied for an electron moving in the circularly polarized laser field in the presence of a strong uniform magnetic field. The results show that the angular distributions of the spectra with respect to the azimuthal and polar angles exhibit different symmetries, respectively, which depend on the fields and electron parameters sensitively and significantly. Moreover, for relatively large parameters such as high laser intensity, high magnetic resonance parameter as well as large initial momentum of electron, the two lobes in spectra tend to the laser-propagating direction so that the radiation can be collimated in the forward direction. Furthermore, an important finding is that by choosing the appropriate fields and initial momentum of electron, the high frequency part of the Thomson scattering spectra can reach the frequency range of soft x-ray,in which a high radiation power per solid angle as ~10^11 a.u. can be obtained. 展开更多
关键词 SPATIAL characteristics STUDIED for an ELECTRON can BE obtained
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DROPWISE CONDENSATION OF STEAM ON ALLOY SURFACES OBTAINED BY ION-IMPLANTATION TECHNIQUE
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作者 Yong-ji Song and Xiao-guang Ren (Liaoyang Petrochem Engineering Institute Liaoyang 111003 CHINA) 《高校化学工程学报》 EI CAS CSCD 1994年第S1期96-103,共8页
DROPWISECONDENSATIONOFSTEAMONALLOYSURFACESOBTAINEDBYION-IMPLANTATIONTECHNIQUEYong-jiSongandXiao-guangRen(Lia... DROPWISECONDENSATIONOFSTEAMONALLOYSURFACESOBTAINEDBYION-IMPLANTATIONTECHNIQUEYong-jiSongandXiao-guangRen(LiaoyangPetrochemEng... 展开更多
关键词 IMPLANTATION TECHNIQUE OBTAINED ALLOY BY
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Instructions for Authors
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《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第1期179-182,共4页
GENERAL INFORMATION International Journal of Ophthalmology--IJO,published continuously since 2008,a global ophthalmological scientific publication and a peer-reviewed,open access periodical published in print and onli... GENERAL INFORMATION International Journal of Ophthalmology--IJO,published continuously since 2008,a global ophthalmological scientific publication and a peer-reviewed,open access periodical published in print and online monthly (ISSN:2222-3959 print,ISSN: 2227-4898 online).IJO is sponsored by the Chinese Medical Association Xi'an Branch,China and obtains guidance,and support from World Health Organization (WHO)and International Council of Ophthalmology (ICO). 展开更多
关键词 INTERNATIONAL JOURNAL ophthalmological SCIENTIFIC obtains GUIDANCE
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Superhard BC_2N:an Orthogonal Crystal Obtained by Transversely Compressing(3,0)-CNTs and(3,0)-BNNTs
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作者 胡玉洁 徐胜亮 +3 位作者 王昊 刘恒 徐雪春 蔡影祥 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期94-98,共5页
By means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called (3,0)- BC2N is predicted, which can be obtained by transversely compressing (3,03 carbon nanotubes (CNTs) an... By means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called (3,0)- BC2N is predicted, which can be obtained by transversely compressing (3,03 carbon nanotubes (CNTs) and boron nitride nanotubes (BNNTs). Its structural stability, elastic properties, mechanical properties and electronic structure are systematically investigated. The results show that (3,0)-BU2N is a superhard material with a direct bandgap. However, its similar structures, (3,0)-C and (3,0)-BN are indirect semiconductors. Strikingly, (3,0)-C is harder than diamond. We also simulate the x-ray diffraction of (3,0)-BC2N to support future experimental investigations. In addition, our study shows that the transition from (3,03 CNTS and BNNTs to (3,0)-BC2N is irreversible. 展开更多
关键词 CNTs and is of BC BNNTs Superhard BC2N:an Orthogonal Crystal Obtained by Transversely Compressing by
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Method for Obtaining Line-of-Sight Rate with a Strap-down Imaging Guidance
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作者 李遗 马艳妮 宋振铎 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期457-462,共6页
In the strap-down TV guidance system, the line-of-sight(LOS) rate can not be obtained frora the measured information, the math platform to select missile attitude information must be set up. The LOS rate selecting m... In the strap-down TV guidance system, the line-of-sight(LOS) rate can not be obtained frora the measured information, the math platform to select missile attitude information must be set up. The LOS rate selecting models based on the missile attitude angle and the rate gyro are set up, the influencing factor and the extracting precision of LOS rate are emulated and analyzed. 展开更多
关键词 strap-down imaging guidance obtaining LOS rate attitude calculation
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Comparison of K_(IC) Values for SiC Whisker Reinforced Ceramic Composites Obtained by Using Various Methods
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作者 Tingquan LEI Guangyong LIN +1 位作者 Shuangxi WANG and Yu ZHOU (Dept. of Metals and Technology, Harbin Institute of Technology, Harbin, 150001, China)(To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第5期331-340,共10页
The fracture toughness (KIC) values determined by indentation microfracture method (IM ) for SiC whisker reinforced Al2O3 and ZrO2 based composites were calculated with different IM equations and compared with those o... The fracture toughness (KIC) values determined by indentation microfracture method (IM ) for SiC whisker reinforced Al2O3 and ZrO2 based composites were calculated with different IM equations and compared with those obtained by singte edge notched beam (SENB) technique. Experimental results show that the KIC (IM) values calculated with different equations are quite different one from another. For composites without phase transformable components the KIC (IM) and KIC (SENB) values are practically on the same level, but for composites with phase transformable components (partially stabilized zirconia) the KIC (SENB) values are always higher than KIC (IM). This is because that the IM method can not reveal sensitively the toughening effect due to dynamic t-m transformation of ZrO2 as the SENB method does. The accuracy of the IM method depends on the Suitability of the IM equations and was evaluated for the materials used in this investigation. Two new IM equations are suggested with which the KIC (IM ) values can be obtained very close to KIC (SENB) values for composites having phase transformable components. 展开更多
关键词 SiC Values for SiC Whisker Reinforced Ceramic Composites Obtained by Using Various Methods Comparison of K IC
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A Method to Obtain Auger Recombination Coefficient in an InGaN-Based Blue Light-Emitting Diode
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作者 汪莱 孟骁 +9 位作者 Jung-Hoon Song Tae-Soo Kim Seung-Young Lim 郝智彪 罗毅 孙长征 韩彦军 熊兵 王健 李洪涛 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第1期107-109,共3页
We propose and demonstrate to derive the Auger recombination coefficient by fitting efficiency-current and carrier lifetime-current curves simultaneously, which can minimize the uncertainty of fitting results. The obt... We propose and demonstrate to derive the Auger recombination coefficient by fitting efficiency-current and carrier lifetime-current curves simultaneously, which can minimize the uncertainty of fitting results. The obtained Auger recombination coefficient is 1.0x10(-31) cm(6)s(-1) in the present sample, which contributes slightly to efficiency droop effect. 展开更多
关键词 InGaN A Method to Obtain Auger Recombination Coefficient in an InGaN-Based Blue Light-Emitting Diode CIE
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Three Kinds of Films Obtained from Plasma Poly-merization of Octamethylcyclotetrasioxane
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作者 刘益民 张广秋 葛袁静 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第2期1253-1259,共7页
Three kinds of 'films' i.e. cross-linked film, grainy film and transparent film, wereobtained in the process of plasma polymerization of Octamethylcyclotetrasioxane(D4) under dif-ferent conditions. From SEM ph... Three kinds of 'films' i.e. cross-linked film, grainy film and transparent film, wereobtained in the process of plasma polymerization of Octamethylcyclotetrasioxane(D4) under dif-ferent conditions. From SEM photos, we can see that the cross-linked film has a network form.From XPS spectra, we can see that the content of Si-C bond of the cross-linked film is lower thanthat of the transparent film, and this result agrees well with the test results of FTIR spectra. Thisproves that the c1eavage of the Si-C bond and C-H bond are the main cleavage in the formationof cross-linked film, whereas the cleavage of the Si-O is the main cleavage in the formation oftransparent film. In order to enhance the collision of the reactive particles and investigate theinfluence of magnetic field on the plasma polymerization, we introduced the magnetic field, as aresult, we got the grainy film. 展开更多
关键词 Three Kinds of Films Obtained from Plasma Poly-merization of Octamethylcyclotetrasioxane SIO
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LIRR's Project of “Study on Spalling Mechanism Mechanism of Dense Refractory Castables by Rapid Heating-up” Being Obtained the Support from National Natural Natural Science Foundation of China
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《China's Refractories》 CAS 2011年第3期21-21,共1页
LIRR's Priject of "Research on Spalling Mechanism Due to Rapid Heating-up of Dense Refractory Castables" declared by Wang Zhanmin,vice-president of LIRR,will gain the fund support from National Natural Science Foun... LIRR's Priject of "Research on Spalling Mechanism Due to Rapid Heating-up of Dense Refractory Castables" declared by Wang Zhanmin,vice-president of LIRR,will gain the fund support from National Natural Science Foundation of China in 2011. 展开更多
关键词 LIRR’s Project of Study on Spalling Mechanism Mechanism of Dense Refractory Castables by Rapid Heating-up Being Obtained the Support from National Natural Natural Science Foundation of China PROJECT
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