Bimesogenic liquid crystals: new materials for high-performance photonics devices and displays

2007 ◽  
Author(s):  
Harry J. Coles
Keyword(s):  
Liquid Crystals ◽  
High Performance ◽  
New Materials ◽  
Photonics Devices

Mineral/microfibrillated cellulose composite materials: High performance products, applications, and product forms

TAPPI Journal ◽  
2018 ◽  
Vol 17 (09) ◽  
pp. 507-515 ◽  
Author(s):  
David Skuse ◽  
Mark Windebank ◽  
Tafadzwa Motsi ◽  
Guillaume Tellier
Keyword(s):  
Composite Materials ◽  
High Performance ◽  
Aqueous Suspension ◽  
Production Capacity ◽  
Cost Savings ◽  
Cost Effective ◽  
New Materials ◽  
Wet Strength ◽  
Product Forms ◽  
Cellulose Composite

When pulp and minerals are co-processed in aqueous suspension, the mineral acts as a grinding aid, facilitating the cost-effective production of fibrils. Furthermore, this processing allows the utilization of robust industrial milling equipment. There are 40000 dry metric tons of mineral/microfbrillated (MFC) cellulose composite production capacity in operation across three continents. These mineral/MFC products have been cleared by the FDA for use as a dry and wet strength agent in coated and uncoated food contact paper and paperboard applications. We have previously reported that use of these mineral/MFC composite materials in fiber-based applications allows generally improved wet and dry mechanical properties with concomitant opportunities for cost savings, property improvements, or grade developments and that the materials can be prepared using a range of fibers and minerals. Here, we: (1) report the development of new products that offer improved performance, (2) compare the performance of these new materials with that of a range of other nanocellulosic material types, (3) illustrate the performance of these new materials in reinforcement (paper and board) and viscosification applications, and (4) discuss product form requirements for different applications.

Synthesis of 3-(Cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8- carboxylic Acids Via an Efficient Three-component Condensation Reaction between Cyclohexylisocyanide and 2-Aminopyridine-3-carboxylic Acid in the Presence of Aromatic Aldehyde

2018 ◽  
Vol 21 (4) ◽  
pp. 298-301 ◽  
Author(s):  
Ghasem Marandi
Keyword(s):  
Biological Sciences ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
High Performance ◽  
Condensation Reaction ◽  
Aromatic Aldehydes ◽  
New Materials ◽  
One Pot ◽  
High Yields ◽  
Benzaldehyde Derivatives

Aim and Objective: The reaction of cyclohexylisocyanide and 2-aminopyridine-3- carboxylic acid in the presence of benzaldehyde derivatives in ethanol led to 3-(cyclohexylamino)-2- arylimidazo[1,2-a]pyridine-8-carboxylic acids in high yields. In a three component condensation reaction, isocyanide reacts with 2-aminopyridine-3-carboxylic acid and aromatic aldehydes without any prior activation. Material and Methods: The synthesized products have stable structures which have been characterized by IR, 1H, 13C and Mass spectroscopy as well as CHN-O analysis. Results: In continuation of our attempts to develop simple one-pot routes for the synthesis of 3- (cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8-carboxylic acids, aromatic aldehydes with divers substituted show a high performance. Conclusion: In conclusion, this study introduces the art of combinatorial chemistry using a simple one-pot procedure for the synthesis of new materials which are interesting compounds in medicinal and biological sciences.

scholarly journals Validation of high-performance liquid chromatographic method for analysis of fluconazole in microemulsions and liquid crystals

2014 ◽  
Vol 50 (2) ◽  
pp. 381-389 ◽  
Author(s):  
Hilris Rocha e Silva ◽  
Fernanda Kolenyak dos Santos ◽  
Gabriela Marielli da Luz ◽  
Marlus Chorilli ◽  
Maria Palmira Daflon Gremião
Keyword(s):  
Liquid Crystals ◽  
High Performance ◽  
High Performance Liquid Chromatographic ◽  
Fungal Diseases ◽  
Cutaneous Lesions ◽  
Ich Guidelines ◽  
Liquid Chromatographic Method ◽  
Site Of Action ◽  
Copaiba Oil ◽  
Liquid Chromatographic

In recent decades, there has been a significant increase in the incidence of fungal diseases. Certain fungal diseases cause cutaneous lesions and in the usual treatment, generally administred orally, the drug reaches the site of action with difficulty and its concentration is too low. An approach much explored in recent years is the development of nanotechnology-based drug delivery systems, and microemulsions (ME) and liquid crystals (LC) are promising. ME and LC were developed with oleic acid or copaiba oil as the oil phase, propoxyl (5OP) ethoxyl (20 OE) cetyl alcohol as surfactant and water. An analytical method to assess the incorporation of fluconazole (FLU) in the systems under study was validated according to guidelines of the International Conference on Harmonization (ICH) guidelines and the Brazilian Food, Drug and Sanitation Agency (ANVISA). The method was conducted on a C18-RP column (250 × 4.6 mm i.d.), maintained at room temperature. The mobile phase consisted of acetonitrile and water (50:50, v/v), run at a flow rate of 1.0mL/min and using ultraviolet detection at 210nm. The chromatographic separation was obtained with a retention time of 6.3min, and was linear in the range of 20-400 µg/mL (r2=0.9999). The specificity showed no interference of the excipients. The accuracy was 100.76%. The limits of detection and quantitation were 0.057 and 0.172 µg.mL-1, respectively. Moreover, method validation demonstrated satisfactory results for precision and robustness. The proposed method was applied for the analysis of the incorporation of FLU in ME and LC, contributing to improve the quality control and to assure the therapeutic efficacy.

ChemInform Abstract: Imidazolium-Based Liquid Crystals: A Modular Platform for Versatile New Materials with Finely Tuneable Properties and Behavior

ChemInform ◽  
2012 ◽  
Vol 43 (15) ◽  
pp. no-no
Author(s):  
Laurent Douce ◽  
Jean-Moise Suisse ◽  
Daniel Guillon ◽  
Andreas Taubert
Keyword(s):  
Liquid Crystals ◽  
New Materials ◽  
Modular Platform ◽  
And Behavior

scholarly journals Hydrothermal Synthesis of rGO-TiO2 Composites as High-Performance UV Photocatalysts for Ethylparaben Degradation

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 520 ◽  
Author(s):  
Miller Ruidíaz-Martínez ◽  
Miguel A. Álvarez ◽  
María Victoria López-Ramón ◽  
Guillermo Cruz-Quesada ◽  
José Rivera-Utrilla ◽  
...  
Keyword(s):  
High Performance ◽  
Photocatalytic Performance ◽  
Raw Materials ◽  
Anatase Phase ◽  
Titanium Isopropoxide ◽  
Rutile Phase ◽  
Pure Tio2 ◽  
New Materials ◽  
Reduced Graphene ◽  
Structural Surface

A series of reduced graphene oxide-TiO2 composites (rGO-TiO2) were prepared by hydrothermal treatment using graphite and titanium isopropoxide as raw materials. The structural, surface, electronic, and optical properties of the prepared composites were extensively characterized by N2 adsorption, FTIR, XRD, XPS, Raman spectroscopy, and DRS. GO was found to be effectively reduced and TiO2 to be in pure anatase phase in all composites obtained. Finally, experiments were performed to evaluate the effectiveness of these new materials as photocatalysts in the degradation of ethylparaben (EtP) by UV radiation. According to the band-gap energies obtained (ranging between 3.09 eV for 4% rGO-TiO2 to 2.55 eV for 30% rGO-TiO2), the rGO-TiO2 composites behave as semiconductor materials. The photocatalytic activity is highest with a rGO content of 7 wt% (7% rGO-TiO2), being higher than observed for pure TiO2 (Eg = 3.20 eV) and achieving 98.6% EtP degradation after only 40 min of treatment. However, the degradation yield decreases with higher percentages of rGO. Comparison with rGO-P25 composites showed that a better photocatalytic performance in EtP degradation is obtained with synthesized TiO2 (rGO-TiO2), probably due to the presence of the rutile phase (14.1 wt %) in commercial P25.

Review on the degradation and device physics of quantum dot solar cells

2015 ◽  
Vol 29 (Supplement 1) ◽  
pp. 1530008 ◽  
Author(s):  
Elham N. Afshar ◽  
Rasoul Rouhi ◽  
Nima E. Gorji
Keyword(s):  
Solar Cells ◽  
Quantum Dot ◽  
Band Gap ◽  
Conversion Efficiency ◽  
High Performance ◽  
Energy Conversion Efficiency ◽  
New Materials ◽  
Quantum Dot Solar Cells ◽  
Photon Conversion ◽  
The Stability

Briefly, we reviewed the latest progress in energy conversion efficiency and degradation rate of the quantum dot (QD) solar cells. QDs are zero dimension nanoparticles with tunable size and accordingly tunable band gap. The maximum performance of the most advanced QD solar cells was reported to be around 10%. Nevertheless, majority of research groups do not investigate the stability of such devices. QDs are cheaper replacements for silicon or other thin film materials with a great potential to significantly increase the photon conversion efficiency via two ways: (i) creating multiple excitons by absorbing a single hot photon, and (ii) formation of intermediate bands (IBs) in the band gap of the background semiconductor that enables the absorption of low energy photons (two-step absorption of sub-band gap photons). Apart from low conversion efficiency, QD solar cells also suffer from instability under real operation and stress conditions. Strain, dislocations and variation in size of the dots (under pressure of the other layers) are the main degradation resources. While some new materials (i.e. perovskites) showed an acceptable high performance, the QD devices are still inefficient with an almost medium rate of 4% (2010) to 10% (2015).

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