A New Approach to the Furan Degradation Problem Involving Ozonolysis of thetrans-Enedione and Its Use in a Cost-Effective Synthesis of Eplerenone

2006 ◽  
Vol 8 (10) ◽  
pp. 2111-2113 ◽  
Author(s):  
Bruce A. Pearlman ◽  
Amphlett G. Padilla ◽  
John T. Hach ◽  
Jeffrey L. Havens ◽  
Muniraj D. Pillai
Keyword(s):  
Cost Effective ◽  
New Approach ◽  
Effective Synthesis ◽  
Degradation Problem

Squaraine chemistry. A new approach to symmetrical and unsymmetrical photoconductive squaraines. Characterization and solid state properties of these materials

1993 ◽  
Vol 71 (4) ◽  
pp. 494-505 ◽  
Author(s):  
Kock-Yee Law ◽  
F. Court Bailey
Keyword(s):  
Solid State ◽  
Condensation Reaction ◽  
Cost Effective ◽  
Squaric Acid ◽  
Reductive Alkylation ◽  
Reaction Sequence ◽  
New Approach ◽  
Effective Synthesis ◽  
Better Than

A new approach to 1-(p-dimethylaminophenyl)-2-hydroxycyclobutene-3,4-dione (4), a precursor for the synthesis of symmetrical and unsymmetrical photoconductive squaraines, is described. In situ generation of p-nitrophenyl ketene, by the reaction of p-nitrophenylacetyl chloride and triethylamine in the presence of tetraethoxyethylene in anhydrous ether, results in a (2 + 2) cycloaddition between the ketene and the electron-rich olefin. The cycloadduct generated, 6, was hydrolyzed to give 1-(p-nitrophenyl)-2-hydroxycyclobutene-3,4-dione (5) in 51% yield. Reductive alkylation of 5 by hydrogen in the presence of formaldehyde in DMF at 50–60 °C affords 4 in 81% yield. The overall yield of 4 is 41% from tetraethoxyethylene and is significantly better than other preparative procedures of 4 based on a partial Friedel–Crafts reaction or an arylation reaction of a squaric acid derivative with an aniline, where yields ranging from 8.5% to 24% were reported. Condensations of 4 with 2 equivalents of N,N-dimethylaniline and its derivatives in refluxing 2-propanol in the presence of 6 equivalents of tributyl orthoformate yield symmetrical squaraine 1a and unsymmetrical squaraines 1b–1e. The synthesis is accomplished by a (2 + 2) cycloaddition – reductive alkylation – condensation reaction sequence and represents a new, cost-effective synthesis for photoconductive squaraines where the expensive squaric acid reactant is bypassed. The spectroscopic and the solid state properties of 1a–1e have been studied. Results show that the properties exhibited by 1a–1e are essentially identical to those exhibited by other photoconductive, symmetrical squaraines that are synthesized by other known processes. From the resemblance in solid state properties, 1a–1e are expected to be photoconductive. This has indeed been observed in preliminary experiments.

Cost Effective Synthesis and Fabrication of Phase-Pure Kesterite Cu2-xZn1.3SnS4 P-type Absorber Layer Thin Films by Solvent Based Process Technique for Photovoltaic Solar Energy Applications

2018 ◽  
Vol 7 (4) ◽  
pp. 36
Author(s):  
B. Khadambari ◽  
S. S. Bhattacharya
Keyword(s):  
Solar Energy ◽  
Renewable Energy Sources ◽  
Cost Effective ◽  
Absorber Layer ◽  
Window Layer ◽  
Energy Applications ◽  
Process Technique ◽  
Absorber Material ◽  
Effective Synthesis ◽  
P Type

Solar has become one of the fastest growing renewable energy sources. With the push towards sustainability it is an excellent solution to resolve the issue of our diminishing finite resources. Alternative photovoltaic systems are of much importance to utilize solar energy efficiently. The Cu-chalcopyrite compounds CuInS2 and CuInSe2 and their alloys provide absorber material of high absorption coefficients of the order of 105 cm-1. Cu2ZnSnS4 (CZTS) is more promising material for photovoltaic applications as Zn and Sn are abundant materials of earth’s crust. Further, the preparation of CZTS-ink facilitates the production of flexible solar cells. The device can be designed with Al doped ZnO as the front contact, n-type window layer (e.g. intrinsic ZnO); an n-type thin film buffer layer (e.g. CdS) and a p-type CZTS absorber layer with Molybdenum (Mo) substrate as back contact. In this study, CZTS films were synthesized by a non-vaccum solvent based process technique from a molecular-ink using a non toxic eco-friendly solvent dimethyl sulfoxide (DMSO). The deposited CZTS films were optimized and characterized by XRD, UV-visible spectroscopy and SEM.

Janus – A New Approach to Air Combat Pilot Training

2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
High Energy ◽  
Training System ◽  
Embedded Sensors ◽  
Pilot Training ◽  
New Approach ◽  
Combat Aircraft ◽  
Air Combat ◽  
The Cost

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.

scholarly journals Fast and Cost-Effective Synthesis of High-Quality Graphene on Copper Foils Using High-Current Arc Evaporation

Materials ◽  
2018 ◽  
Vol 11 (5) ◽  
pp. 804 ◽  
Author(s):  
Helge Lux ◽  
Matthias Edling ◽  
Peter Siemroth ◽  
Sigurd Schrader
Keyword(s):  
Cost Effective ◽  
High Current ◽  
High Quality ◽  
Copper Foils ◽  
Effective Synthesis ◽  
Arc Evaporation

Cost-effective synthesis and solution processing of porous polymer networks through methanesulfonic acid-mediated aldol triple condensation

2018 ◽  
Vol 2 (2) ◽  
pp. 396-401 ◽  
Author(s):  
Zi-Hao Guo ◽  
Chenxu Wang ◽  
Qiang Zhang ◽  
Sai Che ◽  
Hong-Cai Zhou ◽  
...  
Keyword(s):  
Polymer Networks ◽  
Methanesulfonic Acid ◽  
Cost Effective ◽  
Porous Polymer ◽  
Solution Processing ◽  
Condensation Method ◽  
Highly Efficient ◽  
Effective Synthesis ◽  
Scalable Synthesis

A highly efficient aldol triple condensation method was developed for scalable synthesis and solution processing of conjugated porous polymer networks.

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