Lower-temperature processing of potassium niobate films by microwave-assisted hydrothermal deposition technique

A wide range of N-(ethoxycarbonylmethyl)enaminones, prepared by the Eschenmoser sulfide contraction between N-(ethoxycarbonylmethyl)pyrrolidine-2-thione and various bromomethyl aryl and heteroaryl ketones, underwent cyclization in the presence of silica gel to give ethyl 6-(hetero)aryl-2,3-dihydro-1H-pyrrolizine-5-carboxylates within minutes upon microwave heating in xylene at 150 °C. Instead of functioning as a nucleophile, the enaminone acted as an electrophile at its carbonyl group during the cyclization. Yields of the bicyclic products were generally above 75%. The analogous microwave-assisted reaction to produce ethyl 2-aryl-5,6,7,8-tetrahydroindolizine-3-carboxylates from (E)-ethyl 2-[2-(2-oxo-2-arylethylidene)piperidin-1-yl]acetates failed in nonpolar solvents, but occurred in ethanol at lower temperature and microwave power, although requiring much longer time. A possible mechanism for the cyclization is presented, and further functionalization of the newly created pyrrole ring in the dihydropyrrolizine core is described.

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Deposition of orientation-controlled thick (K,Na)NbO3 films on metal substrates by repeated hydrothermal deposition technique

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj2.19008 ◽

2019 ◽

Vol 127 (7) ◽

pp. 478-484 ◽

Cited By ~ 2

Author(s):

Yoshiharu ITO ◽

Akinori TATEYAMA ◽

Yoshiko NAKAMURA ◽

Takao SHIMIZU ◽

Minoru KUROSAWA ◽

...

Keyword(s):

Deposition Technique ◽

Metal Substrates ◽

Hydrothermal Deposition

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Surface morphology of zinc oxide nanorods grown by hydrothermal deposition technique

physica status solidi (c) ◽

10.1002/pssc.200881295 ◽

2009 ◽

Vol 6 (S1) ◽

pp. S150-S153 ◽

Cited By ~ 6

Author(s):

Parameswar Hari ◽

Daryl Spencer

Keyword(s):

Zinc Oxide ◽

Surface Morphology ◽

Zinc Oxide Nanorods ◽

Deposition Technique ◽

Hydrothermal Deposition ◽

Oxide Nanorods

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ZnO nano flowers formation by microwave assisted chemical bath deposition technique

10.1063/1.4732399 ◽

2012 ◽

Author(s):

J. R. Mahajan

Keyword(s):

Chemical Bath Deposition ◽

Deposition Technique ◽

Chemical Bath Deposition Technique ◽

Microwave Assisted

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Microwave-assisted oxidative digestion of lignin with hydrogen peroxide for TOC and color removal

Water Science & Technology ◽

10.2166/wst.2014.535 ◽

2014 ◽

Vol 71 (3) ◽

pp. 390-396 ◽

Cited By ~ 3

Author(s):

Xinping Ouyang ◽

Xiangzhen Huang ◽

Tao Ruan ◽

Xueqing Qiu

Keyword(s):

Hydrogen Peroxide ◽

Organic Carbon ◽

Microwave Irradiation ◽

Conventional Heating ◽

Organic Carbon Content ◽

Aromatic Rings ◽

Digestion Rate ◽

Microwave Assisted ◽

Lower Temperature ◽

Microwave Assisted Digestion

Dilute lignin solution was successfully digested into colorless and clarified liquor under microwave-assisted oxidative digestion with hydrogen peroxide. High dosage of hydrogen peroxide is needed to effectively digest lignin, but excessive hydrogen peroxide may lead to recondensation of formed fragments in digested lignin. Microwave irradiation greatly facilitates the oxidative digestion of lignin. Compared with conventional heating technique, microwave-assisted digestion achieves the same or higher digestion rate within a shorter time and/or at lower temperature. After digestion, total organic carbon content of lignin solution decreases by 93.9%, and a small amount of aliphatic alkane, alcohol, acid and ester are formed via the cleavage of aromatic rings as well as the deprivation of side chains in original lignin. This work provides an alternative way to efficiently treat spent pulping liquor.

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Silicon Tetrachloride Synthesis from Rice Hulls: Transmission and Scanning Electron Microscope Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094437 ◽

1972 ◽

Vol 30 ◽

pp. 236-237 ◽

Cited By ~ 1

Author(s):

Richard S. Thomas ◽

Prabir K. Basu ◽

Francis T. Jones

Keyword(s):

Silicon Tetrachloride ◽

Silica Sand ◽

Mineral Matter ◽

Chemical Heterogeneity ◽

Scanning Electron Microscope Study ◽

Rice Hulls ◽

Hull Structure ◽

Lower Temperature ◽

Image Position ◽

Disposal Problem

Silicon tetrachloride, used in industry for the production of highest purity silicon and silica, is customarily manufactured from silica-sand and charcoal.SiCl4 can also be made from rice hulls, which contain up to 20 percent silica and only traces of other mineral matter. Hulls, after carbonization, actually prove superior as a starting material since they react at lower temperature. This use of rice hulls may offer a new, profitable solution for a rice mill byproduct disposal problem.In studies of the reaction kinetics with carbonized hulls, conversion of SiO2 to SiCl4 was found to proceed within a few minutes to a constant, limited yield which depended reproducibly on the ambient temperature of the reactor. See Fig. 1. This suggested that physical or chemical heterogeneity of the silica in the hull structure might be involved.

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The morphologies and electrical properties of indium contacts on (100) cadmium telluride surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131747 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1422-1423

Author(s):

A.M. Letsoalo ◽

M.E. Lee ◽

E.O. de Neijs

Keyword(s):

Electrical Properties ◽

Cadmium Telluride ◽

Methanol Solution ◽

Electrical Characteristics ◽

Metal Contacts ◽

Deposition Technique ◽

Interfacial Layers ◽

Semiconductor Contacts ◽

Grown Single Crystal ◽

Diamond Abrasive

Semiconductor devices require metal contacts for efficient collection of electrical charge. The physics of these metal/semiconductor contacts assumes perfect, abrupt and continuous interfaces between the layers. However, in practice these layers are neither continuous nor abrupt due to poor nucleation conditions and the formation of interfacial layers. The effects of layer thickness, deposition rate and substrate stoichiometry have been previously reported. In this work we will compare the effects of a single deposition technique and multiple depositions on the morphology of indium layers grown on (100) CdTe substrates. The electrical characteristics and specific resistivities of the indium contacts were measured, and their relationships with indium layer morphologies were established.Semi-insulating (100) CdTe samples were cut from Bridgman grown single crystal ingots. The surface of the as-cut slices were mechanically polished using 5μm, 3μm, 1μm and 0,25μm diamond abrasive respectively. This was followed by two minutes immersion in a 5% bromine-methanol solution.

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