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Efficient Reduction (efficient + reduction)

Distribution by Scientific Domains
Chemistry55%

Selected Abstracts

Efficient Reduction of Graphite Oxide by Sodium Borohydride and Its Effect on Electrical Conductance

ADVANCED FUNCTIONAL MATERIALS, Issue 12 2009
Hyeon-Jin Shin
Abstract The conductivity of graphite oxide films is modulated using reducing agents. It is found that the sheet resistance of graphite oxide film reduced using sodium borohydride (NaBH4) is much lower than that of films reduced using hydrazine (N2H4). This is attributed to the formation of CN groups in the N2H4 case, which may act as donors compensating the hole carriers in reduced graphite oxide. In the case of NaBH4 reduction, the interlayer distance is first slightly expanded by the formation of intermediate boron oxide complexes and then contracted by the gradual removal of carbonyl and hydroxyl groups along with the boron oxide complexes. The fabricated conducting film comprising a NaBH4 -reduced graphite oxide reveals a sheet resistance comparable to that of dispersed graphene. [source]

Ionic Liquid Mediated Efficient Reduction of Nitroarenes Using Stannous Chloride under Sonication.

CHEMINFORM, Issue 38 2005
Ganesha Rai
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Highly Efficient Reduction of Unactivated Aryl and Alkyl Iodides by a Ground-State Neutral Organic Electron Donor.

CHEMINFORM, Issue 27 2005
John A. Murphy
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Convenient and Efficient Reduction of 1,1,-Binaphthyls to H8 -1,1,-Binaphthyl Derivatives with Pd and Ru Catalysts on Solid Support.

CHEMINFORM, Issue 34 2004
Andrei Korostylev
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Facile and Efficient Reduction of Ketones in the Presence of Zinc Catalysts Modified by Phenol Ligands

CHEMISTRY - AN ASIAN JOURNAL, Issue 9 2010
Stephan Enthaler Dr.
Abstract In the present study, the zinc-catalyzed hydrosilylation of various ketones to give their corresponding alcohols has been examined in detail. Diethyl zinc that can be modified by easily accessible phenol ligands allows the efficient reduction of various aryl and alkyl ketones. By using a practical in situ catalyst, excellent turnover frequencies up to 1000,h,1 and a broad functional group tolerance were achieved. Im Rahmen dieser Arbeit wird die Zink-katalysierte Hydrosilylierung von Ketonen zu den entsprechenden Silylethern mit anschließender Hydrolyse zu deren Alkoholen vorgestellt. Wobei exzellente Ausbeuten und Umsätze durch die Modifikation des katalytisch eingesetzten Diethylzink mit Phenolen erreicht werden konnten. Nach genauer Untersuchung verschiedenster Reaktionsparameter konnten turnover frequencies (TOF) von ca. 1000,h,1 erzielt werden. Die hervorragenden Eigenschaften des Katalysatorsystems konnte weiterhin in der Hydrosilylierung verschiedenster Ketone erfolgreich gezeigt werden. Zum besseren Verständnis der Reaktion wurden verschiedene mechanistische Experimente durchgeführt. [source]

Efficient reduction of fault current through the grounding grid of a substation supplied by an overhead line

EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 3 2006
Ljubivoje M. Popovi
Abstract The paper presents a directly applicable and reasonably accurate method for the evaluation of the effects of the counterpoise, the measure for the reduction of the fault current through the substation grounding grid. Under practical conditions the magnitude of the current diverted from a substation grounding grid by the counterpoise conductor is a very complex function of the self and mutual impedances of overhead and underground conductors, substation grounding impedance, transmission line towers resistance, proximity effect between the grounding grid and the counterpoise conductor, as well as on many other factors of lower order. Therefore certain idealizations and simplification of the real physical model were indispensable to develop the mathematical model presented here. The obtained expressions are mostly based on the general equations of a line represented by its lumped parameters and the general equations of uniform ladder circuits. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Influence of Mg on the temperature-dependent optical properties of CdTe quantum dots embedded in Zn0.7Mg0.3Te

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 4 2004
Frank Tinjod
Abstract We compare the temperature-dependent optical properties of CdTe quantum dots with and without Mg in their Zn(Mg)Te barriers. The difficulty of forming CdTe dots on Zn0.7Mg0.3Te barriers (due to the decrease of the lattice mismatch) has been overcome by using a new technique based on an efficient reduction of the surface energy. Mg incorporation in the barriers leads to a better heavy-hole confinement along the growth axis, which is manifested in PL studies by both an extension of the radiative regime temperature range and a strong increase of the activation energy for the non-radiative mechanisms. However, the in-plane confinement is less enhanced, which leads to progressive inter-dot carrier transfers with increasing temperature, as evidenced directly by the analysis of photoluminescence intensities for different single dots. Our temperature-dependent data (time-resolved and micro-photoluminescence) indicate that this transfer consists of a thermally activated process via the two-dimensional wetting-layer states. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Facile and Efficient Reduction of Ketones in the Presence of Zinc Catalysts Modified by Phenol Ligands

CHEMISTRY - AN ASIAN JOURNAL, Issue 9 2010
Stephan Enthaler Dr.
Abstract In the present study, the zinc-catalyzed hydrosilylation of various ketones to give their corresponding alcohols has been examined in detail. Diethyl zinc that can be modified by easily accessible phenol ligands allows the efficient reduction of various aryl and alkyl ketones. By using a practical in situ catalyst, excellent turnover frequencies up to 1000,h,1 and a broad functional group tolerance were achieved. Im Rahmen dieser Arbeit wird die Zink-katalysierte Hydrosilylierung von Ketonen zu den entsprechenden Silylethern mit anschließender Hydrolyse zu deren Alkoholen vorgestellt. Wobei exzellente Ausbeuten und Umsätze durch die Modifikation des katalytisch eingesetzten Diethylzink mit Phenolen erreicht werden konnten. Nach genauer Untersuchung verschiedenster Reaktionsparameter konnten turnover frequencies (TOF) von ca. 1000,h,1 erzielt werden. Die hervorragenden Eigenschaften des Katalysatorsystems konnte weiterhin in der Hydrosilylierung verschiedenster Ketone erfolgreich gezeigt werden. Zum besseren Verständnis der Reaktion wurden verschiedene mechanistische Experimente durchgeführt. [source]

Virtual 3D planning of acetabular fracture reduction

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2008
Musa Citak
Abstract Displaced acetabular fractures are best treated with open reduction to achieve anatomic reduction and maximize the chance of a good functional outcome. Because of the anatomic complexity and often limited visualization, fracture reduction can be difficult. Virtual planning software can allow the surgeon to understand the fracture morphology and to rehearse reduction maneuvers. The purpose of this study was to determine the effect of a novel virtual fracture reduction module on time and accuracy of reduction. Four acetabular fracture patterns were created in synthetic pelves, which were implanted with fiducial markers and were registered with CT scan. Ten surgeons used virtual fracture reduction software or conventional 2D planning methods and immediately reduced the fractures blindly in a viscous gel medium. 3D imaging was again performed and the accuracy of reduction was assessed. The average malreduction was significantly improved following planning with the virtual software compared to the standard technique. The time taken for reduction was also significantly less for two of the four fracture patterns. Virtual software may be useful for visualizing and planning treatment of fractures of the acetabulum, potentially leading to more accurate and efficient reductions, and may also be an effective educational tool. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:547,552, 2008 [source]