Content-Based Image Recognition and Tagging by Deep Learning Methods

Wireless Personal Communications - Deep learning techniques is growing wider day by day in the process of Content based Image retrieval (CBIR). The recognition of the image is based on its shape,...     

Semiconductor‐photocatalyzed degradation of carboxylic acids: Enhancement by particulate semiconductor mixture

Degradation of oxalic acid on particulate TiO₂, ZnO, CuO, Bi₂O₃, In₂O₃, and Nb₂O₅ under UV‐A light exhibits first‐order kinetics, and the degradation rates increase linearly with the photon flux. All the oxides show sustainable photocatalytic activity, and the photonic efficiencies of degradation of oxalate are very much lower than those of the acid. The ease of degradation of carboxylic acids is the following: formic > oxalic > acetic > citric. Intimate mixtures of two different particulate semiconductors kept under suspension and at continuous motion exhibit higher photocatalytic activity, revealing interparticle charge transfer. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 716–726, 2009     

Selectivity in photocatalysis by particulate semiconductors

TiO₂, Fe₂O₃, CuO, ZnO, ZnS, Nb₂O₅, MoO₃, CdO, CdS, Sb₂O₃, CeO₂, HgO, Pb₂O₃, PbO₂ and Bi₂O₃ microparticles exhibit band gap excitation with UV-A light but they are selective to photodegrade phenols. While TiO₂ anatase and ZnO photocatalyze the degradation of phenol, o-aminophenol, m-aminophenol, p-aminophenol, o-chlorophenol, m-chlorophenol, p-chlorophenol, o-nitrophenol, p-nitrophenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol and quinol, MoO₃ does not photodegrade any of the fifteen phenols. Fe₂O₃, CuO, ZnS, Nb₂O₅, CdO, CdS, Sb₂O₃, CeO₂, HgO, Pb₂O₃, PbO₂ and Bi₂O₃ are selective in photodegrading the fifteen phenols; however, the phenols get adsorbed over all sixteen particulate semiconductors.      

FTIR study of the melt grafting of high density polyethylene with amino,sulfonate, and mercapto esters

High-density polyethylene (HDPE) was melt-functionalized with three different esters at 160oC in the presence of dicumyl peroxide (DCP), a free radical initiator, under nitrogen atmosphere at different % weight loadings of esters. DCP and the esters were taken for the melt functionalization reaction in 1:1 ratio. FTIR spectroscopy was used to determine the % grafting of esters onto the HDPE backbone quantitatively. Diethyl mercaptosuccinate (DEMS) produced the highest % grafting with lowest % cross-linking values, whereas anthranilic acid cinnamoyl ester (AACE) yielded the highest % cross-linking with the lowest % grafting values.     

Photomineralization of phenol on Al<Subscript>2</Subscript>O<Subscript>3</Subscript>: synergistic photocatalysis by semiconductors

Phenol gets adsorbed on Al₂O₃ and mineralizes under UV light in the presence of dissolved O₂. The degradation exhibits first-order kinetics and its rate increases linearly with the light intensity and decreases with pH. 2,4-Diphenoxycyclohexanone and 2,6-diphenoxycyclohex-3-ene-1-ol are the intermediates of the reaction. While particulate TiO₂, ZnO, ZnS, Fe₂O₃, CuO, CdO, and Nb₂O₅ individually photocatalyze the degradation, each semiconductor exhibits synergistic photocatalysis, an enhanced photodegradation, when present along with Al₂O₃, indicating electron abstraction by illuminated semiconductors from the phenol adsorbed on Al₂O₃.     

Design and synthesis of a 3,4-dehydroproline amide discovery library

The synthesis of a discovery library of 80 3,4-dehydroproline amides was achieved in a four-step reaction sequence from easily accessible 3-aminoallene-3-carboxylate methyl esters. Diversification of these proline mimics was introduced at five different sites: the substituents at the 3-pyrroline unit (R1, R2, R3), at the nitrogen (R4), and the C-terminus (R5). The 3-pyrroline scaffold was synthesized in excellent yields by a silver-catalyzed intramolecular cyclization of aminoallenes, followed by N-functionalization reactions. Maximum diversity was introduced in the final step of the reaction sequence by taking advantage of the carboxylic acid handle of the 3-pyrroline subunit. Amide coupling reactions using polystyrene-carbodiimide (PS-carbodiimide) and 1-hydroxybenzotriazole (HOBt) under microwave irradiation led to 3,4-dehydroproline amides that were obtained in purities greater than 85% by LC/MS/ESLD after scavenging the excess HOBt on a silica-bound carbonate SPE cartridge.     

Pyrrolidine and piperidine formation via copper(II) carboxylate-promoted intramolecular carboamination of unactivated olefins: diastereoselectivity and mechanism

An expanded substrate scope and in-depth analysis of the reaction mechanism of the copper(II) carboxylate-promoted intramolecular carboamination of unactivated alkenes is described. This method provides access to N-functionalized pyrrolidines and piperidines. Both aromatic and aliphatic gamma- and delta-alkenyl N-arylsulfonamides undergo the oxidative cyclization reaction efficiently. N-Benzoyl-2-allylaniline also underwent the oxidative cyclization. The terminal olefin substrates examined were more reactive than those with internal olefins, and the latter terminated in elimination rather than carbon-carbon bond formation. The efficiency of the reaction was enhanced by the use of more organic soluble copper(II) carboxylate salts, copper(II) neodecanoate in particular. The reaction times were reduced by the use of microwave heating. High levels of diastereoselectivity were observed in the synthesis of 2,5-disubstituted pyrrolidines, wherein the cis substitution pattern predominates. The mechanism of the reaction is discussed in the context of the observed reactivity and in comparison to analogous reactions promoted by other reagents and conditions. Our evidence supports a mechanism wherein the N-C bond is formed via intramolecular syn aminocupration and the C-C bond is formed via intramolecular addition of a primary carbon radical to an aromatic ring.     

T-Count Optimized Wallace Tree Integer Multiplier for Quantum Computing

International Journal of Theoretical Physics - Quantum circuits for performing an arithmetic operation are necessary for the implementation of quantum computing peripherals. An effective quantum...