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收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

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    An NMR and XRD study of solidification/stabilization of chromium with portland cement and beta-C2S
    (1996-06-01)
    Lin, CK
    ;
    Chen, JN
    ;
    Lin, CC
    ;
    環境工程研究所
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    材料科學與工程學系
    Solidificalion/stabilization of chromium with Portland cement Type I and P-dicalcium silicate (beta-C2S) was investigated by means of the Si-29 solid stale Magic Angle Spinning/Nuclear Magnetic Resonance (Si-29 MAS/NMR) and X-ray Diffraction (XRD) techniques. It is found that chromium nitrate can increase the extent of beta-C2S hydration. It is also confirmed that the chromium ion is easily incorporated into the beta-C2S paste and hydrated Portland cement, and that it affects the characteristics of hydration and hydration products. Formation of beta-calcium chromium oxide hydrate (beta-CaCrO4 . 2H2(O)) during the hydration of chromium-doped beta-C2S and calcium chromium oxide hydrate (CaCrO4 . 2H(2)O) during the hydration of chromium-doped Portland cement indicates the substitution of chromium for silicon in hydration products. The chromium ion, Cr3+, is thus stabilized and solidified through this mechanism.
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    Formation of Cr-O and Cr-N-O films serving as Cu oxidation resistant layers and their N-2 pre-sintering effect
    (1998-12-14)
    Chuang, JC
    ;
    Chen, MC
    ;
    電子工程學系及電子研究所
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    Department of Electronics Engineering and Institute of Electronics
    This study investigates the Cu oxidation resistant layers of sputter deposited Cr-O and reactively sputter deposited Cr-N-O of 200 Angstrom thickness. with and without, thermal N-2 pre-sintering treatment. The resistance against Cu oxidation (or the highest annealing temperatures without causing Cu oxidation) of the Cr-O and Cr-N-O covered Cu films were found to be 350 and 500 degrees C, respectively, in an O-2 ambient. The inherent defects in the Cr-O lavers and the nitrogen doping in the Cr-N-O layers were believed to be the principal causes for the distinction of the resistance against Cu oxidation. With Na pre-sintering treatments on the Cr-O or Cr-N-O covered Cu films, the ability of resistance against Cu oxidation was degraded. The higher the N-2 pre-sintering temperature was, the lower the oxidation temperature of Cu became. The N-2 pre-sintering thermal process led to formation of defects on the Cr-O and Cr-N-O layers, resulting in the degradation of the ability of resistance against Cu oxidation. Thus, the application of Cr-O or Cr-N-O as a resistant layer against Cu oxidation should avoid such an excess thermal treatment. (C) 1998 Elsevier Science S.A. All rights reserved.
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    Reversible Cleavage/Formation of the Chromium-Chromium Quintuple Bond in the Highly Regioselective Alkyne Cyclotrimerization
    (2017-11-27)
    Huang, Yu-Siang
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    Huang, Gou-Tao
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    Liu, Yao-Lun
    ;
    Yu, Jen-Shiang K.
    ;
    Tsai, Yi-Chou
    Herein we report the employment of the quintuply bonded dichromium amidinates [Cr{(2)-HC(N-2,6-(Pr2C6H3)-Pr-i)(N-2,6-R2C6H3)}](2) (R=iPr (1), Me (7)) as catalysts to mediate the [2+2+2] cyclotrimerization of terminal alkynes giving 1,3,5-trisubstituted benzenes. During the catalysis, the ultrashort Cr-Cr quintuple bond underwent reversible cleavage/formation, corroborated by the characterization of two inverted arene sandwich dichromium complexes (-(6):(6)-1,3,5-(Me3Si)(3)C6H3)[Cr{(2)-HC(N-2,6-(Pr2C6H3)-Pr-i)(N-2,6-R2C6H3)}](2) (R=Pr-i (5), Me (8)). In the presence of sigma donors, such as THF and 2,4,6-Me3C6H2CN, the bridging arene 1,3,5-(Me3Si)(3)C6H3 in 5 and 8 was extruded and 1 and 7 were regenerated. Theoretical calculations were employed to disclose the reaction pathways of these highly regioselective [2+2+2] cylcotrimerization reactions of terminal alkynes.