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Preparation and nanotribological behavior of PAH/graphite oxide molecular deposition film

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Science China(Technological Sciences) 2004年第4期47卷 385-390页

作者： FENG Dapeng WANG Deguo ZHANG Siwei College of Mechanical and Electronic Engineering University of Petroleum at Beijing Beijing 102200China College of Mechanical and Electronic Engineering University of Petroleum at Beijing Beijing 102200China College of Mechanical and Electronic Engineering University of Petroleum at Beijing Beijing 102200China

Polyallylamine hydrochloride/graphite oxides ultra thin film (coded as PAH/GO ultra thin film) was prepared by molecular deposition (MD) in laboratory. The resulting PAH/GO ultra thin film was heated to convert the electrostatic force towards covalent bond so as to increase the bonding strength of the film. The structure and nanotribological properties of the film were analyzed by means of atomic force microscopy and ultraviolet-visible spectroscopy. It was found that the PAH/GO ultra thin film had a much smaller friction force than the glass substrate and the friction force was dependent on the hardness and appearance of the glass substrate.

关键词： molecular deposition (MD), PAH/GO, nanotribological behavior, afm.

Interfacial behaviors of PMMA-PEO block copolymers at the air/water interface

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Science China Chemistry 2005年第6期48卷 567-573页

作者： CHENG Caixia1, JIAO Tifeng2, TANG Rupei1, LIU Minghua2 & XI Fu1 1. State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 2. CAS Key Laboratory of Colloid and Interface Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China State Key Laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing China CAS Key Laboratory of Colloid and Interface Science Institute of Chemistry Chinese Academy of Sciences Beijing China

Diblock copolymer of PMMA291-b-PEO114 and triblock copolymer of PMMA120-b- PEO227-b-PMMA120 were synthesized and their interfacial properties at the air-water interface were investigated, where both blocks of polyethylene oxide (PEO) and poly(methyl methacrylate) (PMMA) are surface active but the former is soluble in water while the latter is not. Both the block copolymers could form monolayers with two obvious transition regions. The first transition point is around 10 mN/m, which could be assigned to the pancake-brush change of the PEO chains. The other is around 18 mN/m, which could be ascribed to the condensed packing of PMMA. The surface morphological changes during the compression of the Langmuir monolayers are inves-tigated by using the afm.and SEM methods for the films deposited at different surface pressure or molecular areas. At a lower surface pressure, a typical morphology of PEO-con- taining lipopolymers is observed. Upon compression, sphere-dominant morphologies were observed. While the diblock copolymer is easy to folding, the triblock copolymer is in favor of formation of circular domains through vesiculation.

关键词： PMMA-PEO, block copolymers, monolayer, Langmuir-Blodgett films, afm.

Preparation of Gold Nanoparticles Protected with Polyelectrolyte

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Chinese Chemical Letters 2003年第8期14卷 866-869页

作者： XuPingSUN ZheLingZHANG BaiLinZHANG XianDuiDONG ShaoJunDONG ErKangWANG StateKeyLaboratoryofElectroanalyticalChemistry ChangchunInstituteofAppliedChemistryChineseAcademyofSciencesChangchun130022 DepartmentofChemistry SichuanNormalCollegeNanchong637002 StateKeyLaboratoryofElectroanalyticalChemistry ChangchunInstituteofAppliedChemistryChineseAcademyofSciencesChangchun130022

Gold nanoparticles were synthesized through the reduction of tetrachlorauric acid (HAuCl4) by NaBH4, with polyethyleneimine(PEI) as stabilizer. The nanoparticles were characterized by UV-vis spectroscopy and atomic f... 详细信息

关键词： Gold nanoparticle polyelectrolyte UV-vis spectroscopy afm.

Preparation and Characterization of Nano-Structured SiO_(2) Thin Films on Carbon Steel

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Chinese Chemical Letters 2003年第11期14卷 1167-1170页

作者： Rong Chun XIONG Dong Zhou YAN Gang WEI College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029

Nano-structured SiO2 thin films were prepared on the surface of carbon steel for the first time by LPD. The compositions of the films were analyzed by XPS, and the surface morphology of the thin films were observed by afm. The thin films were constituted by compact particles of SiO2, and there was no Fe in the films. In the process of film forming, the SiO2 colloid particles were deposited or absorbed directly onto the surface of carbon steel substrates that were activated by acid solution containing inhibitor, and corrosion of the substrates was avoided. The nano-structured SiO2 thin films that were prepared had excellent protective efficiency to the carbon steel.

关键词： Carbon steel sodium silicate nano-structured SiO_(2) thin films afm.

Recognition of Biotin-functionalized Liposomes

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Chinese Chemical Letters 2003年第8期14卷 832-835页

作者： Hai Feng ZHU Jun Bai LI International Joint Lab The Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080

Functionalized liposomes were prepared by mixing the biotin in the lipid vesicle suspensions. The experiments through immersing streptavidin deposited mica into the biotin modified liposome solution testify the spec... 详细信息

关键词： Recognition liposome TEM afm.

Microstructures of metallic film and diamond growth from Fe-Ni-C system

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Chinese Science Bulletin 2002年第15期47卷 1258-1262页

作者： XU Bin LI Musen YIN Longwei CUI Jianjun LIU Yuxian GONG Jianhong College of Materials Science and Engineering Shandong UniversityJi’nan 250061China Department of Materials Science and Engineering Shandong Institute of Architecture and Engineering

The microstructures of metallic film surrounding diamond have been systemically studied using the transmission electron microscopy (TEM) and the atom force microscopy (afm.. The film can be divided into three layers (inner layer near diamond, external layer near graphite and middle layer). The graphite cannot be directly transformed into diamond in the film at HTHP: there exists a parallelrelationship between (111) of γ-(Fe,Ni) and (110) of Fe3C in the inner layer; the sawtooth-like step morphology found by afm.on the film is similar to that of corresponding diamond surface. A new model for diamond growth at HPHT is proposed from the parallel relationship and sawtooth-like step morphology. It is believed that Fe3C may be a transitional phase in the course of diamond growth, γ-(Fe,Ni) in the inner layer can absorb carbon atom groups with lamella structure from Fe3C, and then the carbon groups stack on growing diamond.

关键词： synthetic diamond high temperature and high pressure metallic film TEM afm.

Imaging of Mica and Graphite Surfaces With the Laser-afm

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Chinese Science Bulletin 1993年第19期38卷 1621-1622页

作者：吴浚瀚成英俊戴长春黄桂珍谢有畅龚立三白春礼 Molecular Biotech Research Center South China Normal University Guangzhou 510631 PRC. Lab of STM Institute of Chemistry Academia Sinica Beijing 100080. PRC. Department of Chemistry Peking University Beijing 100871 PRC. Lab of STM Institute of Chemistry Academia Sinica Beijing 100080 PRC.

In 1986, Binnig et al. developed the first atomic force microscope (afm.. The afm. unlike the scanning tunnelling microscope (STM), has no demands for electrical conductivity, so it has been used in science and technology more widely. In 1988, the afm.was improved, and the afm.employing laser beam deflection for force detection (laser-afm. was developed. In 1990, laser-afm.got the atomic-resolution. Up till now, the afm.has developed into a very important technique for studying the surface.

关键词： mica graphite surface laser afm.

Effect of humidity on the surface adhesion force of inorganic crystals by the force spectrum method

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Chinese Science Bulletin 2001年第11期46卷 912-914页

作者： Tang, J Wang, C Liu, MZ Su, M Bai, CL Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Effect of relative humidity on the surface adhesion force of several inorganic crystals of mica, CaF2 and KC1 was studied by atomic force microscopy (afm.. The results showed that the magnitude of surface adhesion force is mainly dependent on the surface free energy of the adsorbed liquid film, but almost independent of the thickness of the film. Furthermore, the deliquescence on the crystal surface was investigated, which demonstrated the capability of the force spectrum method to monitor changes in ionic concentrations of adsorbed liquid film in real-time.

关键词： mica CaF2 KC1 adhesion force relative humidity afm.

Study of Coal Structure Using STM and afm

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Chinese Science Bulletin 1994年第11期39卷 941-944页

作者：杨起潘治贵汤达祯廖立兵马哲生施倪承 Research Group of Coal Geology China University of Geosciences Beijing 100083 PRC X-ray Laboratory China University of Geosciences Beijing 100083 PRC

The scanning tunneling microscope (STM) and atomic force microscope (afm.are new types of apparatus for surface analysis which were developed successfully byBinnig and others in the 1980s. Because of their high resolution on an atomic scale,they are conveniently suitable to the real-time observation of surface atomic distributionand the study of physical-chemical feature concerned with surface electron *** of STM and afm.to coal research has not yet been reported. Coal

关键词： coal structure graphitization STM afm.