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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

1.Pyrolytic Study of 3-Furylmethylazide 2.Synthesis and Chemistry of 5,6-Dimethylene-5,6-dihydrobenzofuran

Lin, Ya-Mei 31 July 2001 (has links)
Flash vacuum pyrolysis (FVP) of azidomethylthiophene, via a nitrene intermediate, gave a trimer (N,N`-trifurfurylidene-furfurylidene diamine). Use three kinds of methods to synthies benzofuran compound and gain the product by using the third method.
132

(¤@) Pyrolytic and Photolytic Studies of 2-Thiomethoxy- Styrylarenes (¤G) Pyrolytic Studies of 2-(3-Phenylpropenyl)anisole and 2-(1-Phenylpropenyl)anisole (¤T) Synthetic Study of Hexaazatriphenylene Derivatives

Hsu, Chen-Ping 30 June 2008 (has links)
¤@.Pyrolysis of 2-thiomethoxystyrylarenes 15a-c gave 2-(aryl-2-yl)benzo[b]arenes 22a-c and their isomers 23a-c and polycyclic aromatic hydrocarbons (PAH) 24a-c, respectively. Furthermore, pyrolysis of 15c also gave compounds 42¡B43¡B44 by breaking C-N single bond of 15c at higher temperature. In addition, photolysis of 15a-c gave photocyclic products 24a-c and 32a-c, respectively. ¤G.Pyrolysis of 2-(3-phenylpropenyl)anisole(18) and 2-(1-phenyl)anisole (19) gave 2-phenylbenzo[b]furan (13)¡Bbenzofuran (27)¡Bethylbenzene (28) and dibenzyl (29) as the main products. ¤T.Attempts to prepare hexaazatriphenylene derivatives 3 were carried by condensation between diamino dihydropyrazine compound 2 and hexaketocyclohexane (1).
133

(¤@) Pyrolytic and Photolytic Studies of o-Dimethylaminostyrylarenes and Its Derivatives (¤G) Pyrolytic Study of (2-Chlorostyryl)pyridines

Su, Li-Mei 15 July 2008 (has links)
¤@¡BFlash vacuum pyrolysis (FVP) of 2-dimethylaminostilbene and its derivatives via elimination of methyl radical followed by cyclization gave quinoline and 1-methylindole and 3-phenylquinoline and 3-phenylindole. On the other hand, Photolysis of 2-dimethylaminostilbene and its derivatives via electrocyclization gave 1-dimethylaminophenanthrene, phenanthrene, 2-(4-methoxy-phenyl)-1-methyl-1H- quinolin-4-one and 1-methyl-1H-indol-2-yl)phenylmethanone. Photolysis of 2,4'-dimethoxystilbene in acidic sulotion gave 1,6-dimethoxypheanthrene and 1-methoxypheanthrene and ketone compound via electrocyclization followed by [1,9] hydrogen shift. ¤G¡BFVP of 2-(2-chlorostyryl)pyridine gave benzo[f]quinolin, benzo[h]quinolin, on the other hand, FVP of 4-(2-chlorostyryl)pyridine gave different benzo[h]quinolin.
134

(¤@) Pyrolytic and Photolytic Studies of 2-(Dimethylamino)styrylarenes and 2-(Benzylmethylamino)styrylarenes (¤G) Pyrolytic Study of Benzoic 1,3-Dimethyl-2-indolyl Anhydride

Peng, Jheng-syong 27 July 2009 (has links)
¤@.Pyrolysis of 2-(N,N-dimethylamino)styrylarenes (29a-e) and 2-(N,N- benzylmethylamino)styrylarenes (30a-f) both gave 2-(ar-2-yl)- benzo[b]arenes 35a-f, 39a-e, their isomers 36a-e, 40a-e and the other products. On the other hand, photolysis of 29a-e gave electrocyclic products 2, 57b-e and 22a-e, respectively. However photolysis of 30a-f only gave the complicated and unknown compounds. ¤G.Pyrolysis of benzoic 1,3-dimethyl-2-indolyl anhydride (54) gave (1,3-dimethylindol-2-yl)phenylmethanone (63), 1,3-dimethylindole (65) and bis(1,3-dimethylindol-2-yl)methanone (66) as the main products.
135

A new UHV cleavage-evaporation and analysis system for the study of metal-semiconductor contacts

許小亮, Xu, Xiaoliang. January 1996 (has links)
published_or_final_version / Physics / Master / Master of Philosophy
136

COMPUTER ANALYSIS OF ACTIVE DEVICES FOR INTEGRATED THERMIONIC CIRCUITS

Feugate, Robert J., 1946- January 1974 (has links)
No description available.
137

Vacuum ultraviolet laser spectroscopy of small molecules

Miller, Bradley E. 05 1900 (has links)
No description available.
138

Vacuum removal of sulphur and tin from liquid steel

Persson, Hans Arne. January 1981 (has links)
No description available.
139

Residual copper in steel : significance, vacuum removal

Salomon-de-Friedberg, Henry January 1976 (has links)
No description available.
140

New cyclisations of iminyl radicals generated by flash vacuum pyrolysis

Ieva, Maria January 2012 (has links)
The formation of iminyl radicals from a range of precursors, including hydrazone imines and oxime ethers, under FVP conditions is well documented in the literature.1 Once formed, the iminyl radical can undergo cyclisation onto various aromatic ring systems including phenyl rings, thiophenes and furans to form new fused aromatics.2 The aim of this thesis was to expand the scope of cyclisation of iminyl radical onto pyrrole-type rings and 2-azole rings, generating novel heterocyclic cores via pyrolysis of the corresponding oxime ether precursors. In addition, the cyclisation of iminyl radicals onto C-C double bonds was investigated and afforded isoquinolines shown in Scheme II, providing a new way to synthesise these heterocyclic cores. Mechanistic predictions were supported by DFT calculations in which the thermodynamics and kinetics of the systems were established and the products of iminyl cyclisation reactions were characterised using a range of 2D NMR experiments.

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