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Chinese Annals of Mathematics,Series B 2000年第4期21卷 441-452页

作者： D. H. BOO C. G. PARK Department of Mathematics Chungnam National University TaeJon 305-764 Korea

Assume that each completely irrational noncommutative torus is realized as an inductive limit of circle algebras, and that for a completely irrational noncommutative torus Aω of rank m there are a completely irrational noncommutative torus Aρ of rank m and a positive integer d such that tr（Aω） = tr（Aρ）. It is proved that the set of all C*-algebras of sections of locally trivial C*-algebra bundles over S2 with fibres Aω. has a group structure, denoted by π1（Aut（Aω.））, which is isomorphic to Z if d > 1 and {0} if d > 1. Let Bcd be a cd-homogeneous C*-algebra over S2 x T2 of which no non-trivial matrix algebra can be factored out. The spherical noncommutative torns Sρcd is defined by twisting C*（T2 x Zm-2） in Bcd C* （Z（m-2）） by a totally skew multiplier ρ on T2 x Z（m-2）. It is shown that Sρcd Mp∞ is isomorphic to C（S2） C* （T2 x Zm-2, ρ） Mcd（C） Mp∞ if and only if the set of prime factors of cd is a subset of the set of prime factors of p.

关键词： C*-algebra bundle Homogeneous C*-algebra Crossed product UHF-algebra Cuntz algebra

GENERALIZED SIMPLE NONCOMMUTATIVE TORI

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Chinese Annals of Mathematics,Series B 2002年第4期23卷 539-544页

作者： C. G. PARKDepartment of Mathematics, Chungnam National Uinversity, taejon 305-764, South Korea. Department of Mathematics Chungnam National Uinversity Taejon 305-764 South Korea

The generalized noncommutative torus Tkp of rank n was defined in [4] by the crossed product Am/k ×a3 Z ×a4 … ×an Z, where the actions ai of Z on the fibre Mk(C) of a rational rotation algebra Am/k are trivial, and C*(kZ × kZ) ×a3 Z ×a4 ... ×an Z is a completely irrational noncommutative torus Ap of rank n. It is shown in this paper that Tkp is strongly Morita equivalent to Ap, and that Tkp (?) Mp∞ is isomorphic to Ap (?) Mk(C) (?) Mp∞ if and only if the set of prime factors of k is a subset of the set of prime factors of p.

关键词： Noncommutative torus Equivalence bimodule UHF-algebra Cuntz algebra Crossed product

Preparation and characterization of 3-dimensionally ordered macroporous SiC

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Science China(Technological Sciences) 2006年第1期49卷 1-9页

作者： KIM Dong-pyo Department of Fine Chemical Engineering and Chemistry of Chungnam National University Taejon 305-764 South Korea

Three-dimensionally (3D) long range ordered macroporous SiC ceramics were prepared through infiltrating polymethylsilane (PMS) into the 3D ordered sacrificial silica template, pyrolysis and the template removal. It was found that the pore size (84―658 nm), BET surface area (299.44―584.64 m2/g) and micropore volume (0.25―0.64 cm3/g) of the achieved porous SiC can be tailored by utilizing different sizes silica sphere templates. There exist three kinds of pores in the porous ceramics: sphere inversed pores, windows and mesopores (2―5 nm). The sphere inversed pores were packed as hcp structure and three dimensionally penetrated through the windows, and the mesopores endowed the porous ceramics surprising high BET surface areas and micropore volumes.

关键词： three-dimensionally ordered materials, templated technique, preceramic polymer conversion technique, SiC ceramic.

Preparation of patterned SiC and SiCN microstructures

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Science China(Technological Sciences) 2006年第2期49卷 164-171页

作者： SUNG In-kyung KIM Dong-pyo Department of Fine Chemical Engineering and Chemistry of Chungnam National University TaejonSouth Korea 305-764

Patterned SiC and SiCN microstructures were successfully fabricated on the silicon substrates by using polydimethylsiloxane (PDMS) elastometric stamp as template, polycarbosilane (PCS) and polysilazane (PSZ) as preceramic polymers. The preparing process was followed by precursor infiltration, the curing of the precursor, demolding of the template and pyrolysis of the cured preceramic polymer pattern. It shows that the dimen- sions of the ceramic patterns can be tailored by using the PDMS molds with different di- mensions. The produced ceramic microstructures can be potentially applied in high tem- perature and high pressure environments due to the advanced properties of the SiC and SiCN ceramics.

关键词： micro-fabrication technique, soft lithography, elastomeric stamp, non-oxide ceramics, patterning.

Fe-Ti oxide and Fe-Cu sulfide exsolution in amphibole cumulate xenoliths from granodiorite in Tongling,Anhui Province

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Chinese Science Bulletin 2003年第23期48卷 2626-2634页

作者： QINXinlong DUYangsong H.K.Lee YINJingwu GUOXifeng EducationMinistryKeyLaboratoryofLithosphereTectonicsandExplorationTechnology ChinaUniversityofGeosciencesBeijing100083China DepartmentofGeology CollegeofNaturalSciencesChungnamNationalUniversityTaejon305-764RepublicofKorea

A number of Fe-Ti oxide and Fe-Cu sulfide exsolution phases are found in amphibole cumulate xenoliths from Mesozoic granodioritic plutons at Jiguanshi and Jin- kouling in Tongling, Anhui Province. Most of amphiboles in the xenoliths have been identified as pargasite, and deter-mined as a crystallization phase in the lower crust. The oxide exsolutions commonly acicular, are distributed parallel to [100] of amphibole with a typical Schiller texture. They con-tain 0.29%—51.07% of TiO2, and correspond to magnetite, titaniferous magnetite, titanomagnetite or ilmenite. All ex-solved sulfide grains, being rounded to extended rounded in shape, are regularly arranged in sub-paralleled or closely beaded groups, except for a few of grains that are scattered or isolated. The exsolved sulfide phases comprise mostly pyrrhotite, secondarily cubanite and chalcopyrite, and rarely pyrite. A few grains of magnetite can coexist with pyrrhotite in most samples. The sulfide phases are poor in nickel (usu-ally Ni < 0.5%, Ni/Fe < 0.003), while relative enrichments in copper (up to 2.93%) typify the pyrrhotite. Additionally, both oxides and sulfides may be exsolved in the same area of amphibole. Occurrence of Fe-Ti oxide and Fe-Cu sulfide exsolution phases in the xenoliths leads to inference that ore-forming materials such as S, Fe, Cu, etc. have been pri-marily dissolved in Mesozoic magma within the lower crust beneath the Tongling area.

关键词：闪石捕虏岩花岗闪长岩安徽 Fe-Ti氧化物 Fe-Cu硫化物

Contrast in Fluid M etallogeny between the Tianmashan Au-S Deposit and the Datuanshan Cu Deposit in Tongling,Anhui Province

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 116-124页

作者： LEE Hyun Koo Depatment of Geology Chungnam National University 220 Kungdong Yuseong Ku Taejon 305-764 Republic of Korea

A comprehensive contrast of ore-forming geological background and ore-forming fluid features, especially fluid ore-forming processes, has been performed between the Tianmashan and the Datuanshan ore deposits in Tongling, Anhui Province. The major reasons for the formation of the stratabound skarn Au-S ore deposit in Tianmashan and the stratabound skarn Cu ore deposit in Datuanshan are analyzed in accordance with this contrast. The magmatic pluton in Tianmashan is rich in Au and poor in Cu, but that in Datuanshan is rich in Cu and Au. The wallrock strata in Tianmashan contain Au-bearing pyrite layers with some organic substance but those in Datuanshan contain no such layers. Moreover, the ore-forming fluids in Tianmashan are dominantly magmatic ones at the oxide and sulfide stages, but those with high content of Cu in Datuanshan are mainly groundwater fluids. In addition, differences in compositional evolution and physicochemical condition variation of the ore-forming fluids result in gradual dispersion

关键词： fluid inclusion fluid ore-forming process contrast in fluid metallogeny Au-S ore deposit Cu ore deposit magmatic fluid groundwater fluid Tongling Anhui Province

FTIR Studies on NO Adsorption on [Co+Mg(Sr)] /ZSM-5

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Chemical Research in Chinese Universities 2002年第4期18卷 389-392页

作者： LEE C. W. CHONG P. J. KRICT Taejon 305-606 KoreaKRICT Taejon 305-606 Korea

The adsorption of NO on /ZSM-5 zeolites with different contents was studied by means of FTIR spectroscopy. The dominant NO species adsorbed on /ZSM-5 was found to be in a dinitrosyl form, as demonstrated by the IR bands at 1 813 and 1 896 cm -1. NO was adsorbed in a mononitrosyl form as shown in the region of 1 937-1 939 cm -1 as a minor species. Samples /ZSM-5 showed a new band near 1 858 cm -1(w) attributable to the species of Co_3O_4-NO. It was found that zeolite /ZSM-5 exhibits superior performance characteristics for SCR of NO molecules, and is promising as a useful catalyst. The typical catalyst /ZSM-5 for SCR resulted from the collaboration of the metal alkalinity and the ionic radius of the metal(such as Mg or Sr).

关键词： Infrared spectroscopy Nitric oxide Adsorption Mononitrosyl Dinitrosyl Cobalt oxide

Effects of Paper Mill Sludge on Potassium, Sodium, Calcium, and Magnesium Concentrations in Different Soybean Cultivars

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Pedosphere 2005年第1期15卷 84-94页

作者： YANXiang-Kui K.W.CHANG H.L.XU NationalInstituteforAgro-EnvironmentalSciences Tsukuba-shi305-8506Japan／／GansuAgriculturalUniversityLanzhou730070China AgrochemistryDepartment ChungnamNationalUniversityKung-DongTaejon305-764Korea InternationalNatureFarmingResearchCenter 5632HataNagano390-1401（Japan）

A field experiment was conducted on a sandy loam soil at an Experimental Farm in taejon, South Korea, to determine the effects of paper mill sludge compost application rates on K, Na, Ca and Mg concentrations of soybean (Glycine max (L.) Merr.) aboveground tissues and the genotypic effects on the concentrations of these elements. Sludge compost treatments of 0, 75, and 150 t ha-1 were applied to 30 diverse soybean cultivars. Concentrations of K, Na, Ca, and Mg in aboveground tissues harvested 69 days after …

关键词： calcium magnesium paper mill sludge potassium sodium soybean

Effects of compressive stress on the nonlinear electromechanical behavior of ferroelectric ceramics

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Science China(Technological Sciences) 2006年第1期49卷 29-37页

作者： LEE Jung-Ju KIM Hyun Cheol Department of Mechanical Engineering KAIST Taejon 305-701 Korea

The effects of compressive stress parallel and perpendicular to the polar axis of PZT ceramics on the nonlinear electromechanical behavior of the materials has been experimentally studied. A domain-switching model that divides each 180° switching to two successive 90° switching is proposed to explain these effects. In the case of stress parallel to the polar axis, domain switching in the ceramics is approximately axisymmetric and can be simulated by an analytical model. While in the case of stress perpendicular to the polar axis, domain switching is three-dimensional and cannot be simplified. The simulated re-sults that match the experiments well show the validity of the proposed domain-switching model.

关键词： ferroelectric ceramics, domain switching, electromechanical, PZT.

Longitudinal and Transverse Incremental Permeability in Mu-metal Thin Films

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Journal of Materials Science & Technology 2000年第2期16卷 197-198页

作者： W.S. Cho, T.S. Yoon and C. O.Kim (Division of Material Eng., Chungnam Natl. Univ., taejon 305-764, Korea) H.B.Lee (Department of Physics Education, Kong in Nail. Univ., Kongju 314-701, Korea) Division of Material Eng. Chungnam Natl. Univ. Taejon 305-764 South Korea Department of Physics Education Kongju Natl. Univ. Kongju 314-701 South Korea

The transverse permeability ratio (TPR) and longitudinal permeability ratio (LPR) as a function of an external field of mumetal films have been investigated in conjunction with the magnetic properties. The mumetal films were prepared by the *** sputtering method in Ar atmosphere. The LPR curve shows the single peak pattern, and the TPR curve shows the double peak pattern indicating the existence of the magnetic anisotropy effect. The magnitude of the incremental permeability are strongly depended on the magnetic softness. The large changes of LPR and TPR in low external fields can be useful for the evaluation of the magnetic softness.

关键词： Thin In Longitudinal and Transverse Incremental Permeability in Mu-metal Thin Films