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Lie symmetrical perturbation and adiabatic invariants of generalized Hojman type for Lagrange systems 被引量:8
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作者 罗绍凯 陈向炜 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3176-3181,共6页
Based on the invariance of differential equations under infinitesimal transformations of group, Lie symmetries, exact invariants, perturbation to the symmetries and adiabatic invariants in form of non-Noether for a La... Based on the invariance of differential equations under infinitesimal transformations of group, Lie symmetries, exact invariants, perturbation to the symmetries and adiabatic invariants in form of non-Noether for a Lagrange system are presented. Firstly, the exact invariants of generalized Hojman type led directly by Lie symmetries for a Lagrange system without perturbations are given. Then, on the basis of the concepts of Lie symmetries and higher order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for the system with the action of small disturbance is investigated, the adiabatic invariants of generalized Hojman type for the system are directly obtained, the conditions for existence of the adiabatic invariants and their forms are proved. Finally an example is presented to illustrate these results. 展开更多
关键词 Lagrange system Lie symmetrical perturbation exact invariant adiabatic invariant of generalized Hojman type
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Lie Symmetrical Perturbation and Adiabatic Invariants of Generalized Hojman Type for Disturbed Nonholonomic Systems 被引量:5
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作者 罗绍凯 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第11期3017-3020,共4页
For a nonholonomic mechanics system with the action of small disturbance, the Lie symmetrical perturbation and adiabatic invariants of generalized Hojman type are studied under general infinitesimal transformations of... For a nonholonomic mechanics system with the action of small disturbance, the Lie symmetrical perturbation and adiabatic invariants of generalized Hojman type are studied under general infinitesimal transformations of groups in which the generalized coordinates and time are variable. On the basis of the invariance of disturbed nonholonomic dynamical equations under general infinitesimal transformations, the determining equations, the constrained restriction equations and the additional restriction equations of Lie symmetries of the system are constructed, which only depend on the variables t, qs and q^.s. Based on the definition of higher-order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for a nonholonomic system with the action of small disturbance is investigated, and the Lie symmetrical adiabatic invariants, the weakly Lie symmetrical adiabatic invariants and the strongly Lie symmetrical adiabatic invariants of generalized Hojman type of disturbed nonholonomic systems are obtained. An example is given to illustrate applications of the results. 展开更多
关键词 coated conductor buffer layer self-epitaxy CeO2
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Noether symmetry and non-Noether conserved quantity of the relativistic holonomic nonconservative systems in general Lie transformations 被引量:3
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作者 罗绍凯 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3182-3186,共5页
For a relativistic holonomic nonconservative system, by using the Noether symmetry, a new non-Noether conserved quantity is given under general infinitesimal transformations of groups. On the basis of tile theory of i... For a relativistic holonomic nonconservative system, by using the Noether symmetry, a new non-Noether conserved quantity is given under general infinitesimal transformations of groups. On the basis of tile theory of invariance of differential equations of motion under general infinitesimal transformations, we construct the relativistic Noether symmetry, Lie symmetry and the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations. By using the Noether symmetry, a new relativistic non-Noether conserved quantity is given which only depends on the variables t, qs and qs. An example is given to illustrate the application of the results. 展开更多
关键词 RELATIVITY holonomic nonconservative system Noether symmetry non-Noethcr con-served quantity
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Study on the Camouflage-Protective and Dyeing Properties of Natural Dye Indigo 被引量:4
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作者 周岚 邵建中 柴丽琴 《Journal of Donghua University(English Edition)》 EI CAS 2010年第1期46-51,共6页
There are two major camouflage protections in modern military tactics:UV-protection and near infrared camouflage.However,not all natural and composite dyestuffs provide the mentioned properties.In this study,the cotto... There are two major camouflage protections in modern military tactics:UV-protection and near infrared camouflage.However,not all natural and composite dyestuffs provide the mentioned properties.In this study,the cotton fabric was dyed with natural indigo and the natural indigo dyeing process was optimized.Green leaves were chosen as the simulating object,and the camouflage properties of the dyed cotton fabric were evaluated.It was observed that the dyed cotton fabric had good UV-protection and near-infrared camouflage properties.The UV-protection effect was strongly dependent on the absorption characteristics of natural indigo for UV radiation.The near infrared camouflage effect was mainly dependent on the reflection spectrum characteristics of natural indigo in the near infrared waveband. 展开更多
关键词 natural indigo DYEING ultraviolet protection near infrared camouflage
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Exploring the cooperation effect of DBD byproducts and Ag/TiO_2 catalyst for water treatment in an APPJ system 被引量:1
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作者 Guangliang CHEN Wei HU +2 位作者 Jinsong YU Wenxia CHEN Jun HUANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第1期64-71,共8页
In this paper,the collective effects of combining heterogeneous Ag/TiO2 nanocomposite catalyst with the byproducts(primarily the irradiation and the O3 species) of an atmospheric pressure plasma jet(APPJ) system o... In this paper,the collective effects of combining heterogeneous Ag/TiO2 nanocomposite catalyst with the byproducts(primarily the irradiation and the O3 species) of an atmospheric pressure plasma jet(APPJ) system on the degradation of methyl orange(MO) were explored.The heterostructured Ag/TiO2 nanocomposite was achieved via decorating the Ag quantum dots(QDs) on the commercially available TiO_2catalyst(P25) through a hydrothermal method.The x-ray diffraction analysis of the nanocomposite catalyst showed the diffraction peaks at 44.3°,64.4°,and 77.5°,corresponding to the Ag planes of(200),(220) and(311),respectively.The high resolution transmission electron microscope characterization of the nanocomposite catalyst indicated that the Ag QDs with an average diameter of 5 nm were homogeneously distributed on the P25 surface.The experimental results on the MO photodegradation showed that the APPJ irradiation had a marginal effect on the cleavage of the MO molecules.When the Ag/TiO2 nanocomposite catalyst was used,the photodegradation rate of MO increased about 5 times.When both the APPJ byproducts and the Ag/TiO2 nanocomposite catalyst were used,however,over 90% of the MO in the tested solution was cleaved within 15 min,and the energy efficiency was about 0.6 g/k W h.Moreover,an optimal Ag dosage value was determined(6 wt%).The catalytic results indicated that combining the DBD plasma byproducts with heterogeneous nanocomposite catalysts may be an effect protocol for decreasing the application cost of the DBD system and mitigating the environment pollution by organic dyes in the textile industry. 展开更多
关键词 APPJ plasma byproduct heterostructured catalyst organic wastewater treatment
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Feature Extraction of Fabric Defects Based on Complex Contourlet Transform and Principal Component Analysis 被引量:1
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作者 吴一全 万红 叶志龙 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期282-286,共5页
To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform (CCT) and principal component analysis (PC... To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform (CCT) and principal component analysis (PCA) is proposed.Firstly,training samples of fabric defect images are decomposed by CCT.Secondly,PCA is applied in the obtained low-frequency component and part of highfrequency components to get a lower dimensional feature space.Finally,components of testing samples obtained by CCT are projected onto the feature space where different types of fabric defects are distinguished by the minimum Euclidean distance method.A large number of experimental results show that,compared with PCA,the method combining wavdet low-frequency component with PCA (WLPCA),the method combining contourlet transform with PCA (CPCA),and the method combining wavelet low-frequency and highfrequency components with PCA (WPCA),the proposed method can extract features of common fabric defect types effectively.The recognition rate is greatly improved while the dimension is reduced. 展开更多
关键词 fabric defects feature extraction complex contourlet transform(CCT) principal component analysis(PCA)CLC number:TP391.4 TS103.7Document code:AArticle ID:1672-5220(2013)04-0282-05
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Influence of Mica Particles on the Rheological Properties and Thermal Stability of Poly( lactic acid) 被引量:1
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作者 朱凤博 张顺花 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期433-436,共4页
The influence of mica particles on the rheological and thermal properties of poly( lactic acid)( PLA) / mica composites were investigated by capillary rheometer and thermogravimetric( TG)analysis. The results show tha... The influence of mica particles on the rheological and thermal properties of poly( lactic acid)( PLA) / mica composites were investigated by capillary rheometer and thermogravimetric( TG)analysis. The results show that the PLA / mica blends are nonNewtonian pseudoplastic and display shear-thinning. The value of non-Newtonian index of the blends melt decreased obviously with the addition of mica particles but somehow even increased when shear rate exceeded 4 500 s- 1. In this work,it could be indicated that appropriate amount of mica particles could somehow enhance the resistance of PLA melt under high shear rate to deviate from Newtonian fluid. TG analysis shows that the thermal stability of PLA decreases a little after the incorporation of the mica particles.As mica particles decompose in a completely different way in contrast to PLA,this abnormal decrease of thermal stability of PLA / mica composite may be attributed to moisture stored between mica layers released at high temperature. 展开更多
关键词 poly(lactic acid)(PLA) mica particles rheological behavior thermal stability
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Effect of Polyvinylpyrrolidone on the Morphologies of Latex Films and Air Permeability of the Latex Finished Fabrics 被引量:1
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作者 沈一峰 叶佳佳 +2 位作者 杨雷 吴明华 倪天翔 《Journal of Donghua University(English Edition)》 EI CAS 2010年第3期339-344,共6页
Low air permeability is a common problem happening to the coating finished and pigment dyed fabrics.To tackle the problem,styrene and butyl acrylate copolymer latex was prepared and used as substitute for the binder.T... Low air permeability is a common problem happening to the coating finished and pigment dyed fabrics.To tackle the problem,styrene and butyl acrylate copolymer latex was prepared and used as substitute for the binder.Then,polyvinylpyrrolidone(PVP)was fed into the latex.It was expected that pores could form in the resulting latex film after being rinsed.The morphologies of the latex films were analysized by scanning electric microscope(SEM).It was found that the continuity of the latex films decreased greatly because of the addition of PVP,leading to the loss of the stress at break of the films.After rinsing with methanol aqueous solution,PVP was easily leached off and(macro)void was formed in the latex films.The size of the void decreased with the increase of the PVP concentration.Then,the latex with and without PVP was used to finish the cotton fabrics and engaged as binder in pigment dyeing.After PVP was rinsed out,the air permeability of the fabrics improved greatly,which recovered to that of the unfinished one.In the meantime,the color fastness to rubbing was little affected.So,the method of PVP addition could be termed as an efficient way to improve the air permeability in coating and dyeing industry. 展开更多
关键词 latex film BINDER air permeability pigment dyeing
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PREPARATION AND CATALYTIC ACTIVITY OF BIOACTIVE FIBERS
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作者 陈文兴 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第5期441-447,共7页
Two kinds of water-soluble metallophthalocyanines, binuclear cobalt phthalocyanine (Co2Pc2) and binuclear ferric phthalocyanine (Fe2Pc2), were synthesized through phenylanhydride-urea route and characterized by el... Two kinds of water-soluble metallophthalocyanines, binuclear cobalt phthalocyanine (Co2Pc2) and binuclear ferric phthalocyanine (Fe2Pc2), were synthesized through phenylanhydride-urea route and characterized by elemental analysis and FT-IR spectra. Binuclear metallophthalocyanine derivatives (Mt2Pc2) were immobilized on silk fibers and modified viscose fibers to construct bioactive fibers of mimic enzyme. Mt2Pc2 was used as the active center of bioactive fibers, viscose and silk fibers as the microenvironments. The catalytic oxidation ability of bioactive fibers on the malodors of methanthiol and hydrogen sulfide was investigated at room temperature. The experimental results indicated that the catalytic activity of such bioactive fibers was closely correlative to the types ofbioactive fibers and substrates. 展开更多
关键词 Silk fibers Viscose fibers Bioactive fibers Mimic enzyme METALLOPHTHALOCYANINE Catalytic oxidation.
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First principles studies on the electronic structures of LiMxFe1-xPO4 (M = Co, Ni and Rh)
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作者 欧阳小芳 施思齐 +4 位作者 欧阳楚英 姜迪友 刘德生 叶志清 雷敏生 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期3042-3045,共4页
The local crystal structures and electronic structures of LiMxFe1-xPO4 (M = Co, Ni, Rh) are studied through first-principles calculations. The lattice constants and unit cell volumes are smaller for the Co and Ni do... The local crystal structures and electronic structures of LiMxFe1-xPO4 (M = Co, Ni, Rh) are studied through first-principles calculations. The lattice constants and unit cell volumes are smaller for the Co and Ni doped materials than for pure LiFePO4, while larger than for the Rh doped material. The local structures around M atoms in the doped materials are studied in details. The total density of states (DOS) and atomic projected DOS (PDOS) are all calculated and analysed in detail. The results give a reasonable prediction to the improvement of electronic conductivity through Fe-site doping in LiFePO4 material. 展开更多
关键词 electronic properties density of states first principles OLIVINE
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Synthesis and Characterization of Naphthalenesulfonic Formaldehyde Condensates for Improving the Solubility of C.I. Reactive Blue 19 in Alkali Liquor
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作者 南旭莹 姚玉华 邵建中 《Journal of Donghua University(English Edition)》 EI CAS 2008年第6期649-653,共5页
The solubility of C.I. reactive blue 19 in aqueous alkali is poor, so it isn't used to dye cellulosic fiber in cold pad-batch dyeing. In order to improve the solubility of this dyestuff in alkali liquor, the right... The solubility of C.I. reactive blue 19 in aqueous alkali is poor, so it isn't used to dye cellulosic fiber in cold pad-batch dyeing. In order to improve the solubility of this dyestuff in alkali liquor, the right dispersants will be needed. A series of condensates are synthesized by changing the synthesis conditions such as the ratio of naphthalenesulfonic (N) to formaldehyde (F), acidity, and their compositions are confirmed by MS spectrum. It is found that in acidity scope of 20%-24% and the ratio of N to F 1∶0.33, the synthesized condensates can efficiently improve the solubility of C.I. reactive blue 19 in alkali liquor. In addition, the influences of the condensates on the exhaust dyeing and the cold pad-batch dyeing are tested. 展开更多
关键词 C. I. reactive blue 19 solubility in alkali liquor condensates of na phthalenesul fonic- formaldeh yde exhaust dyeing cold pad-batch dyeing
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Preparation and Catalytic Oxidation Activity on 2-mercaptoethanol of a Novel Catalytic Cellulose Fibres
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作者 姚玉元 李英杰 +4 位作者 陈文兴 吕汪洋 吕素芳 徐敏虹 刘凡 《Journal of Donghua University(English Edition)》 EI CAS 2007年第4期451-454,共4页
Cobalt tetra(N-carrbonylacrylic) aminophthalocyanine was supported on cellulose fibres by graft reaction to obtain a novel polymer catalyst, catalytic cellulose fibres (CCF), and the optimal supporting conditions ... Cobalt tetra(N-carrbonylacrylic) aminophthalocyanine was supported on cellulose fibres by graft reaction to obtain a novel polymer catalyst, catalytic cellulose fibres (CCF), and the optimal supporting conditions were pH = 6,80℃, t = 120 min. The catalytic oxidation activity of CCF towards oxidation of 2-mercaptoethanol (MEA) in aqueous solution was investigated. The experimental results demonstrated that CCF had good catalytic oxidation activity on MEA at room temperature, causing no secondary pollution and remaining efficient for the repetitive tests with no obvious decrease of catalytic activity. 展开更多
关键词 METALLOPHTHALOCYANINE cellulose fibres 2-MERCAPTOETHANOL polymer catalyst graft reaction
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Preparation of Latex Film with Macropores and Their Applications in Pigment Dyeing
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作者 沈一峰 杨雷 +1 位作者 叶佳佳 陈丽 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期846-851,共6页
Aiming at improving the permeability of the pigment dyed fabrics,two kinds of hydrophilic polymers(polyvinyl pyrrolidone(PVP),and polyethylene glycol(PEG)were fed into the styrene-butyl acrylate(St-BuA)copolymer latex... Aiming at improving the permeability of the pigment dyed fabrics,two kinds of hydrophilic polymers(polyvinyl pyrrolidone(PVP),and polyethylene glycol(PEG)were fed into the styrene-butyl acrylate(St-BuA)copolymer latex binder respectively to prepare films with macropores.The effects of the post-added polymers on the latex film formation process and film structures were studied and the performance of the dyed fabrics was evaluated.It was found that the drying process could still be divided into three stages even after the addition of PVP and PEG.And the water evaporation rate during the first and last stage remained the same as usual.However,after the addition of PVP,the onset of the second stage was delayed to high volume fraction,and PVP formed into spherical dispersion phase with 300 nm in diameter.It provided a great deal of interface between the latex polymer and the PVP phase,which led to an increase in the water evaporation rate during the second stage.A different case was found after the feeding of PEG.Firstly,the first stage ended at low volume fraction and a decreased evaporation rate was observed in the second stage.Secondly,the PEG dispersion appeared as finger-like structure in the transmission electron microscopy(TEM)images with 9μm in length.After rinsing,pores were found only in the films formerly containing PVP or PEG,and the shapes and the sizes were closely correlated with the initial morphologies of the PVP or PEG domains.However,the shade of color,the abrasion fastness,and the permeability of the dyed fabric were independent of the type of the post-added hydrophilic polymer. 展开更多
关键词 latex film BINDER PERMEABILITY pigment dyeing
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Numerical Simulation of the Morphology and Moving Velocity for Electrospun Stable Jet
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作者 李妮 薛花 熊杰 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期15-17,共3页
GAMBIT,POLYFLOW and FLUENT POST were used to simulate the morphology and the velocity of electrospun stable jet.Simulation results shows that jet diameter decreases with the increased draw force acted on the stable je... GAMBIT,POLYFLOW and FLUENT POST were used to simulate the morphology and the velocity of electrospun stable jet.Simulation results shows that jet diameter decreases with the increased draw force acted on the stable jet.But too great draw force would lead to thick knots appearing along the jet or stable jet disappearing during electrospinning.There is a linear relationship between the velocity and the moving distance.But the linear relationship does not exist under great draw force. 展开更多
关键词 ELECTROSPINNING stable jet numerical simulation
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Ultra-high specific surface area activated carbon from Taihu cyanobacteria via KOH activation for enhanced methylene blue adsorption
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作者 Yifang Mi Wenqiang Wang +4 位作者 Sen Zhang Yalong Guo Yufeng Zhao Guojin Sun Zhihai Cao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期106-116,共11页
Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu cyanobacteria.When the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs ... Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu cyanobacteria.When the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs possessed an ultra-high specific surface(2178.90 m^(2)·g^(-1))and plenty of micro-and meso-pores,as well as a high pore volume(1.01 cm^(3)·g^(-1)).Ascribed to ultra-high surface area,π-π interaction,electrostatic interaction,as well as hydrogen-bonding interactions,the CBACs displayed huge superiority in efficient dye removal.The saturated methylene blue adsorption capacity by CBACs could be as high as 1143.4 mg·g^(-1),superior to that of other reported biomass-activated carbons.The adsorption was endothermic and modeled well by the pseudo-second-order kinetic,intra-particle diffusion,and Langmuir models.This work presented the effectiveness of Taihu cyanobacteria adsorbent ascribed to its super large specific surface area and high adsorption ability. 展开更多
关键词 Activated carbon BIOMASS Dye adsorption Taihu cyanobacteria
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Synthesis of poly[methyl(3,3,3-trifluoropropyl)siloxane]-b-poly(ethylene oxide) block copolymers 被引量:3
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作者 Xiao-li ZHAN Bi CHEN +3 位作者 Qing-hua ZHANG Ling-min YI Bo JIANG Feng-qiu CHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第9期1304-1308,共5页
A series of new amphiphilic poly[methyl(3,3,3-trifluoropropyl)siloxane]-b-poly(ethylene oxide) (PMTFPS-b-PEO) diblock copolymers with different ratios of hydrophobic segment to hydrophilic segment were prepared ... A series of new amphiphilic poly[methyl(3,3,3-trifluoropropyl)siloxane]-b-poly(ethylene oxide) (PMTFPS-b-PEO) diblock copolymers with different ratios of hydrophobic segment to hydrophilic segment were prepared by coupling reactions of end-functlonal PMTFPS and PEO homopolymers. Copolymers were shown to be well defined and narrow molecular weight distribution (MWD) (1.07-1.3) by characterizations such as gel permeation chromatography (GPC) and ^1H-nudear magnetic resonance (^1H-NMR). 展开更多
关键词 Block copolymers POLYSILOXANES FLUOROPOLYMERS Synthesis POLYETHYLENEOXIDE
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Three different low-temperature plasma-based methods for hydrophilicity improvement of polyethylene films at atmospheric pressure 被引量:2
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作者 陈光良 郑旭 +4 位作者 黄俊 司晓蕾 陈致力 薛飞 Sylvain Massey 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期411-417,共7页
Three different low-temperature plasma-based methods were used to improve the surface hydrophilicity of polyethy- lene (PE) films, and all the modification processes were carried out by employing an atmospheric pres... Three different low-temperature plasma-based methods were used to improve the surface hydrophilicity of polyethy- lene (PE) films, and all the modification processes were carried out by employing an atmospheric pressure plasma jet (APPJ) system. (a) PE films were directly modified by APPJ using a gas mixture of He and 02. (b) Acrylic acid (AA) was introduced into the system and a polymer acrylic acid (PAA) coating was deposited onto the PE films. (c) AA was grafted onto the PE surface activated by plasma pre-treatment. It was found that the hydrophilicity of the PE films was significantly improved for all the three methods. However, the samples modified by Process (a) showed hydrophobicity recovery after a storage time of 20 days while no significant change was found in samples modified by Process (b) and Process (c). The Fourier transform infrared spectroscopy (FTIR) results indicated that the most intensive C=O peak was detected on the PE surface modified by Process (c). According to the X-ray photoelectron spectroscopy (XPS) analysis, the ratios of oxygen-containing polar groups for samples modified by Process (b) and Process (c) were higher than that modified by Process (a). 展开更多
关键词 atmospheric pressure plasma jet plasma modification acrylic acid hydrophilicity improvement
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Tuning the morphologies of SiC nanowires via the change of the Co_xSi_y melts 被引量:2
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作者 J.J.Chen Y.Pan +1 位作者 W.H.Tang Q.Shi 《Nano-Micro Letters》 SCIE EI CAS 2010年第1期11-17,共7页
SiC nanowires and SiC/SiO2 core-shell structural nanowires were synthesized via a simple thermal evaporation of CoxSiy melts at the temperature of 1500?C. The morphologies and yields of those SiC nanowires can be tune... SiC nanowires and SiC/SiO2 core-shell structural nanowires were synthesized via a simple thermal evaporation of CoxSiy melts at the temperature of 1500?C. The morphologies and yields of those SiC nanowires can be tuned by altering the composition of CoxSiy. Nanowires obtained by thermal evaporation of Co Si are composed of SiC/SiO2 core-shell nanostructures with lengths up to several hundreds of micrometers, diameters of 4050 nm, and the thickness of amorphous SiO2 wrapping shell about 20 nm. SiC nanowires prepared by thermal evaporation of Co Si2 and Co2 Si melt are found to be hexagonal-prism-shaped nanorods, and the diameter of those nanorods is about 150 nm and the length is about 10 microns. All the SiC nanowires obtained possess [111] preferred growth direction with a high density stacking faults and twin defects. Taking into consideration the binary alloy diagram of Co Si and the participation of oxygen, we propose the vapor-solid growth mechanism of SiC nanowires and discuss the effect of the supersaturation of Si O on the morphology and yields of SiC nanowires. 展开更多
关键词 Silicon carbide NANOWIRES MORPHOLOGY
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A New Type of Non-Noether Adiabatic Invariants for Disturbed Lagrangian Systems: Adiabatic Invariants of Generalized Lutzky Type 被引量:1
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作者 罗绍凯 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第9期2463-2466,共4页
For a Lagrangian system with the action of small disturbance, the Lie symmetrical perturbation and a new type of non-Noether adiabatic invariant are presented in general infinitesimal transformation groups. On the bas... For a Lagrangian system with the action of small disturbance, the Lie symmetrical perturbation and a new type of non-Noether adiabatic invariant are presented in general infinitesimal transformation groups. On the basis of the invariance of disturbed Lagrangian systems under general infinitesimal transformations, the determining equations of Lie symmetries of the system are constructed. Based on the definition of higher-order adiabatic invariants of a mechanical system, a new type of adiabatic invariant, i.e. generalized Lutzky adiabatic invariants, of a disturbed Lagrangian system are obtained by investigating the perturbation of Lie symmetries t'or a Lagrangian system with the action of small disturbance. Finally, an example is given to illustrate the application of the method and results. 展开更多
关键词 coated conductor buffer layer self-epitaxy CEO2
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Sphere-to-rod transition of short-chain PEO-b-PDMS-b-PEO in aqueous solution induced by copolymer concentration
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作者 Xiao Li Zhan Bi Chen +1 位作者 Qing Hua Zhang Ling Min Yi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1363-1366,共4页
A short-chain triblock copolymer EO9-DMS7-EO9 was synthesized by coupling reaction of allyl-terminated poly(ethylene oxide) and Si-H-terminated poly(dimethylsiloxane). The structure and purity of synthesized copol... A short-chain triblock copolymer EO9-DMS7-EO9 was synthesized by coupling reaction of allyl-terminated poly(ethylene oxide) and Si-H-terminated poly(dimethylsiloxane). The structure and purity of synthesized copolymer was carefully characterized. Self-assembly behavior of EO9-DMST-EO9 triblock copolymer in water was investigated. And it was found that along with the increase of copolymer concentration, morphology of self-assembled aggregates transits from sphere to rod. A plausible understanding of the morphology transition for the investigated triblock copolymer was proposed. 展开更多
关键词 Block copolymer Self-assembly POLYSILOXANE Morphology transition
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