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In;#8197;Situ Studies of Solvothermal Synthesis of Energy Materials
Abstract not provided
Synthesis, Crystal and Electronic Structure of the Titanium Bismuthides Sr 5 Ti 12 Bi 19+ x , Ba 5 Ti 12 Bi 19+ x , and Sr 5- δ Eu δ Ti 12 Bi 19+ x ( x ≈ 0.5-1.0; δ ≈ 2.4, 4.0): Synthesis, Crystal and Electronic Structure of the Titanium Bismuthides Sr5Ti12Bi19+x, Ba5Ti12Bi19+x, and Sr5-δEuδTi12Bi19+x (x ≈ 0.5-1.0; δ ≈ 2.4, 4.
Not provided.
Ligand and Linkage Isomers of Bis(ethylthiocarbamato) Copper Complexes with Cyclic C 6 H 8 Backbone Substituents: Synthesis, Characterization, and Antiproliferation Activity
Abstract A series of isomeric bis(alkylthiocarbamate) copper complexes have been synthesized, characterized, and evaluated for antiproliferation activity. The complexes were derived from ligand isomers with 3‐methylpentyl (H 2 L 2 ) and cyclohexyl (H 2 L 3 ) backbone substituents, which each yield a pair of linkage isomers. The thermodynamic products CuL 2a/3a have two imino N and two S donors resulting in three five‐member chelate rings (555 isomers). The kinetic isomers CuL 2b/3b have one imino and one hydrazino N donor and two S donors resulting in four‐, six‐, and five‐member rings (465 isomers). The 555 isomers have more accessible Cu II/I potentials (E 1/2 =−811/−768 mV vs. ferrocenium/ferrocene) and lower energy charge transfer bands than their 465 counterparts (E 1/2 =−923/‐854 mV). Antiproliferation activities were evaluated against the lung adenocarcinoma cell line (A549) and nonmalignant lung fibroblast cell line (IMR‐90) using the MTT assay. CuL 2a was potent ( A549 EC 50 =0.080 μM) and selective ( IMR‐90 EC 50 / A549 EC 50 =25) for A549. Its linkage isomer CuL 2b had equivalent A549 activity, but lower selectivity ( IMR‐90 EC 50 / A549 EC 50 =12.5). The isomers CuL 3a and CuL 3b were less potent with A549 EC 50 values of 1.9 and 0.19 M and less selective with IMR‐90 EC 50 / A549 EC 50 ratios of 2.3 and 2.65, respectively. There was no correlation between reduction potential and A549 antiproliferation activity/selectivity.
Synthesis of Bis-1,2,4-triazines via Telescoped Condensation of [1,10]-Phenanthroline-2,9-dicarbonitrile with Aromatic 1,2-Dicarbonyls
Efficient separation of minor actinides from spent nuclear fuel remains a formidable challenge. As part of ongoing efforts to identify effective ligands for separation of toxic radionuclides, a series of bis-1,2,4-triazines, three novel, have been prepared in this paper from [1,10]-phenanthroline-2,9-dicarbonitrile in two-telescoped steps without additives, complicated workups, prolonged reaction times, or additional purification.
Synthesis of highly dispersed, block copolymer‐grafted TiO 2 nanoparticles within neat block copolymer films
ABSTRACT The objective of the study is to formulate exclusive block copolymer (BCP) nanocomposites by dispersing bcp end‐grafted nanoparticles (bcp‐ g ‐nps) of PMMA‐ b ‐PS‐ g ‐TiO 2 within PS‐ b ‐PMMA matrix. PMMA‐ b ‐PS‐ g ‐TiO 2 is synthesized using a “grafting‐to” approach and characterized by XPS and TGA to establish that the copolymer chains were bonded to NPs. Good dispersion of bcp‐ g ‐nps in PMMA and PS‐PMMA bcp films is observed, in contrast to poor dispersion in PS films. In PS‐PMMA films, the compatible and identical bcp nature of the end‐grafted polymer, and large NP size caused it to span across entire PS‐PMMA domains. Poor and good dispersion in PS and PMMA matrices, respectively, can be rationalized by the fact that NPs interactions are driven by the PMMA at the outer corona of the bcp‐ g ‐nps. Developing bcp‐ g ‐nps as a strategic route to preparation of highly dispersed high permittivity NPs like titanium dioxide (TiO 2 ) in bcp matrix can have important ramifications for energy storage devices. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53 , 468–478
Synthesis, characterization, and photovoltaic properties of dithienylbenzobisazole‐dithienylsilole copolymers
ABSTRACT Three conjugated polymers comprised of dioctyl‐dithieno‐[2,3‐ b :2',3'‐ d ]silole and a donor‐acceptor‐donor triad of either cis‐ benzbisoxazole, trans ‐benzobisoxazole or trans ‐benzobisthiazole were synthesized via the Stille cross‐coupling reaction. The impact of varying the heteroatoms and/or the location within the benzobisazole moiety on the optical and electronic properties of the resulting polymers was evaluated via cyclic voltammetry and UV‐Visible spectroscopy. All of the polymers have similar optical band‐gaps of ∼1.9 eV and highest occupied molecular orbital levels of − 5.2 eV. However, the lowest unoccupied molecular orbitals (LUMO) ranged from − 3.0 to − 3.2 eV. Interestingly, when the polymers were used as donor materials in bulk‐heterojunction photovoltaic cells with PC 71 BM as the electron‐acceptor, the benzobisoxazole‐based polymers gave slightly better results than the benzobisthiazole‐containing polymers with power conversion efficiencies up to 3.5%. These results indicate that benzobisoxazoles are promising materials for use in OPVs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53 , 1533–1540
Input signal synthesis for open-loop multiple-input/multiple-output testing.
Abstract not provided.
Polyol Synthesis of Cobalt–Copper Alloy Catalysts for Higher Alcohol Synthesis from Syngas
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Controlled Generation of TiO x –Au Interface Using Titanium Molecular Complex Bearing Pyridyl Anchors: Synthesis, Characterization and Catalysis
Interfacial perimeter sites between metal and support are often important for catalysis. A mononuclear titanium siloxy complex III, Ti(acac) 2 [OSiC 6 H 5 N(OCH 3 ) 2 ] 2 was synthesized to generate TiOx units of different degrees of clustering to decorate Au nanoparticles. Two different methods of preparation were examined; one was to deposit III onto Au/SiO 2 and the other was to form III-covered Au nanoparticle first before deposition onto SiO 2 . The former method generated more highly dispersed TiO x units, while larger domains of TiO 2 were formed with the latter method, as deduced by UV–vis and XAS characterization. A model was proposed to explain how TiO x dispersity could be related to the preparative procedures. These samples were further tested as catalysts in selective oxidation of propane in a stream of O 2 and H 2 . They exhibited different product selectivities. The sample with more dispersed TiO x units were more selective for acetone formation versus propene formation. The results confirmed the important role of both the Au–TiO x interface at the perimeter and the extent of Ti isolation in the TiO x phase in the reaction.
Magneto-acoustic Interfacial Reaction-Based Nanoparticle Synthesis: A Direct Path to Manufacturing Metal Matrix Nanocomposites
This work investigates a novel nanoparticle fabrication methodology: combined reaction and acoustic cavitation abrasion of a solid in contact with a liquid. Magneto-Acoustic Mixing Technology is used to produce nanometer- to micron-sized particles by chemical and acoustic mechanisms between diamond particles and a stainless steel surface in the presence of a metallic liquid (Mg), where it is found that particle–surface interactions and cavitation generate particles more efficiently together than independently, producing unique chemistries. The individual and combined influence of sonic power and chemical reaction on particle size, volume fraction, chemistry, magnetic properties, and applicability to metal matrix nanocomposite fabrication are studied.