scholarly journals Separation and identification of indene–C70 bisadduct isomers

2016 ◽  
Vol 12 ◽  
pp. 903-911 ◽  
Author(s):  
Bolong Zhang ◽  
Jegadesan Subbiah ◽  
David J Jones ◽  
Wallace Wing Ho Wong
Keyword(s):  
Organic Solar Cell ◽  
High Performance ◽  
Analytical Techniques ◽  
Geometric Isomer ◽  
Device Performance ◽  
Solar Cell Device ◽  
Vis Spectroscopy ◽  
Initial Work ◽  
Pure Isomer ◽  
C Nmr

Following an initial work on the isolation of a single geometric isomer from an indene–C70 bisadduct (IC70BA) mixture, we report the full fractionation and identification of the bisadduct species in the material. Eleven fractions of IC70BA isomers were separated by high-performance liquid chromatography. A number of fractions contained relatively pure isomer species and their configuration were deduced using a variety of analytical techniques including 1H and 13C NMR and UV–vis spectroscopy. The electrochemical properties and the organic solar cell device performance were investigated for fractions where a reasonable quantity of sample could be isolated.

scholarly journals Effect of molecular weight on the properties and organic solar cell device performance of a donor–acceptor conjugated polymer

2015 ◽  
Vol 6 (12) ◽  
pp. 2312-2318 ◽  
Author(s):  
Zeyun Xiao ◽  
Kuan Sun ◽  
Jegadesan Subbiah ◽  
Tianshi Qin ◽  
Shirong Lu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Solar Cell ◽  
Conjugated Polymer ◽  
Organic Solar Cell ◽  
Photophysical Properties ◽  
Device Performance ◽  
Solar Cell Device ◽  
Donor Acceptor

The effect of molecular weight of a conjugated polymer on its photophysical properties and solar cell device performance was investigated.

scholarly journals Synthesis, Characterization and Evaluation of Supercapacitive Response of Dodecylbenzenesulphonic Acid (DBSA) Doped Polypyrrole/Zirconium Dioxide Composites

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 4035
Author(s):  
Rizwan Ullah ◽  
Mehtab Khan ◽  
Rozina Khattak ◽  
Nadia Khan ◽  
Muhammad Sufaid Khan ◽  
...  
Keyword(s):  
High Performance ◽  
Specific Capacity ◽  
Synthesis Method ◽  
Analytical Techniques ◽  
High Energy ◽  
High Energy Density ◽  
X Ray Diffraction ◽  
Vis Spectroscopy ◽  
Micro Morphology ◽  
Synthesized Materials

An in-situ chemical oxidative method was used to effectively synthesize a promising supercapacitor material based on PPy/ZrO2 composites. The synthesized materials were characterized by different analytical techniques, such as UV/visible (UV/Vis) spectroscopy, Fourier-transform infra-red spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The inclusion of ZrO2 into the PPy matrix was verified by vibrational spectra and structural analyses. The (TGA) results showed that incorporating ZrO2 into the polymeric matrix improved its thermal stability. In addition, the electrochemical properties of the synthesizedmaterials were investigated byusing cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The PPy/ZrO2 composite demonstrated excellent super capacitive performance, and high specific capacity of 337.83 F/g, with an exceedingly high energy density of 187.68 Wh/kg at a power density of 1000 W/kg. The composite materials maintain good stability after 1000 charge and discharge cycles, with 85% capacitance retention. The PPy/ZrO2 possesses a high capacitance, an attractive micro-morphology, and a simple synthesis method. The findings indicate that the PPy/ZrO2 composite could be a promising electrode material for high-performance supercapacitor applications.

Direct Correlation of the Organic Solar Cell Device Performance to the In-Depth Distribution of Highly Ordered Polymer Domains in Polymer/Fullerene Films

2013 ◽  
Vol 3 (11) ◽  
pp. 1463-1472 ◽  
Author(s):  
Sebastian Engmann ◽  
Chetan R. Singh ◽  
Vida Turkovic ◽  
Harald Hoppe ◽  
Gerhard Gobsch
Keyword(s):  
Solar Cell ◽  
Organic Solar Cell ◽  
Depth Distribution ◽  
Device Performance ◽  
Solar Cell Device

Phytoceuticals in aniseeds: a practical approach for isolation and identification

2016 ◽  
Vol 5 (01) ◽  
pp. 4701
Author(s):  
Shobha R. I. ◽  
Andallu B.
Keyword(s):  
Chronic Diseases ◽  
Column Chromatography ◽  
High Performance ◽  
Methanolic Extract ◽  
Analytical Techniques ◽  
Therapeutic Agents ◽  
Systematic Research ◽  
Isolation And Identification ◽  
Traditional System ◽  
Pharmacologically Active

Nature has provided mankind with a broad and structurally diverse array of pharmacologically active chemical compounds, phytoceuticals, which have proved to be indispensable for the cure of chronic diseases or as lead structures for novel therapeutic agents. Almost, 70% of modern medicines in India have been developed from plants used in the traditional system of medicine. With the technological advances and the development of more sophisticated isolation and analytical techniques, there is great scope for further systematic research to screen and isolate many more phytoceuticals which might be more effective/as effective as synthetic drugs and thereby assess their potential in protecting against chronic diseases. The present investigation is aimed at isolation and identification of phytoceuticals in a spice, aniseed (Pimpinella anisum L), therapeutically less-exploited and widely used only for culinary purpose, using analytical techniques viz. column chromatography, high performance thin layer chromatography (HPTLC.) and nuclear magnetic resonance spectrometry. Among all the solvent fractions of methanolic extract tested, methanolic extract and ethyl acetate fraction possessed highest amounts of bioactive compounds viz. phenolics, flavonoids, flavonols which was confirmed by qualitative, quantitative and HPTLC. analyses. Spectral analysis using NMR. of one of the sub-fractions of aniseeds obtained by column chromatography, revealed the presence of a glycosylated flavone, luteolin-6C-glucoside in aniseeds.  The present study revealed aniseeds to be a great source of bioactive phytoceuticals which can be novel candidates for development of new therapeutic agents.

Improving the Organic Semiconductor- Metal Contact Interface in Printed High Performance Organic TFTs

2012 ◽  
Vol 1402 ◽  
Author(s):  
Kanan Puntambekar ◽  
Lisa Stecker ◽  
Kurt Ulmer ◽  
Themistokles Afentakis ◽  
Steven Droes
Keyword(s):  
Organic Semiconductor ◽  
High Performance ◽  
Thin Film Transistor ◽  
Device Performance ◽  
Organic Thin Film ◽  
Contact Interface ◽  
Organic Thin Film Transistor ◽  
Metal Electrodes ◽  
Free Surfaces ◽  
Gas Plasma

ABSTRACTOptimization of the interface between the organic semiconductor (OSC) & the source-drain (S/D) electrode is critical in order to improve organic thin film transistor (OTFT) device performance. This process typically involves coating the metal S/D electrodes with an optimal self-assembled thiol layer; a process that requires pristine metal surfaces for successful treatment. Obtaining contamination free surfaces can be challenging in the case of printed metal electrodes. Here we demonstrate an effective strategy to address this issue by introducing a brief low power forming gas plasma treatment prior to the surface coating step. We show a two orders of magnitude decrease in the contact resistance as a result of this treatment.

scholarly journals Determination of amino acids in human biological fluids by high-performance liquid chromatography: critical review

Amino Acids ◽  
2021 ◽  
Author(s):  
Grażyna Gałęzowska ◽  
Joanna Ratajczyk ◽  
Lidia Wolska
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
High Performance ◽  
Hplc Analysis ◽  
Limit Of Detection ◽  
Biological Fluids ◽  
Analytical Techniques ◽  
Epidemiological Studies ◽  
Preparation Conditions

AbstractThe quantitation and qualification of amino acids are most commonly used in clinical and epidemiological studies, and provide an excellent way of monitoring compounds in human fluids which have not been monitored previously, to prevent some diseases. Because of this, it is not surprising that scientific interest in evaluating these compounds has resurfaced in recent years and has precipitated the development of a multitude of new analytical techniques. This review considers recent developments in HPLC analytics on the basis of publications from the last few years. It helps to update and systematize knowledge in this area. Particular attention is paid to the progress of analytical methods, pointing out the advantages and drawbacks of the various techniques used for the preparation, separation and determination of amino acids. Depending on the type of sample, the preparation conditions for HPLC analysis change. For this reason, the review has focused on three types of samples, namely urine, blood and cerebrospinal fluid. Despite time-consuming sample preparation before HPLC analysis, an additional derivatization technique should be used, depending on the detection technique used. There are proposals for columns that are specially modified for amino acid separation without derivatization, but the limit of detection of the substance is less beneficial. In view of the fact that amino acid analyses have been performed for years and new solutions may generate increased costs, it may turn out that older proposals are much more advantageous.

An expanded isoindigo unit as a new building block for a conjugated polymer leading to high-performance solar cells

2014 ◽  
Vol 2 (15) ◽  
pp. 5427-5433 ◽  
Author(s):  
Shugang Li ◽  
Zhongcheng Yuan ◽  
Jianyu Yuan ◽  
Ping Deng ◽  
Qing Zhang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Building Block ◽  
Conjugated Polymer ◽  
High Performance ◽  
Fill Factor ◽  
Solar Cell Device ◽  
Donor Acceptor ◽  
First Time

An expanded isoindigo unit (IBTI) has been incorporated into a donor–acceptor conjugated polymer for the first time. The PCE of the solar cell device based on the new polymer reached 6.41% with a fill factor of 0.71.

A study of the decomposition behaviour of 12-tungstophosphate heteropolyacid in solution

2003 ◽  
Vol 81 (10) ◽  
pp. 1044-1050 ◽  
Author(s):  
Zhirong Zhu ◽  
Ruan Tain ◽  
Colin Rhodes
Keyword(s):  
Aqueous Solution ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Potentiometric Titration ◽  
Inductively Coupled Plasma ◽  
High Performance ◽  
Atomic Emission ◽  
Inductively Coupled ◽  
Vis Spectroscopy ◽  
Decomposition Behaviour

In this paper, the decomposition of H3PW12O40 in aqueous solution or in mixed solutions of water–ethanol or water–acetone is investigated by potentiometric titration and 31P NMR. Identification of the products from H3PW12O40 decomposition over a pH range of 1–12 was achieved using preparation high performance liquid chromatography (Pre-HPLC) combined with IR, UV–vis spectroscopy, and inductively coupled plasma atomic emission spectroscopy (ICP). It is found that H3PW12O40 in aqueous solution decomposes in a stepwise fashion with increasing pH, with the following solution compositions: [PW12O40]3– (at pH ~ 1) [Formula: see text] [PW12O40]3– + [P2W21O71]6– + [PW11O39]7– (at pH 2.2) [Formula: see text] [PW12O40]3– + [P2W21O71]6– + [PW11O39]7– + [P2W18O62]6– + [P2W19O67]10– (at pH 3.5) [Formula: see text] [P2W21O71]6– + [PW11O39]7– + [P2W18O62]6– (at pH 5.4) [Formula: see text] [PW9O34]9– (at pH 7.3) [Formula: see text] PO43– + WO42– (pH > 8.3). In the first stages at pH < 8, H3PW12O40 decomposes partially with removal of W=O units. In the second stage at pH > 8, tungstophosphoric completely decomposes to PO43–. In contrast, the decomposition of H3PW12O40 is reduced, or the stability of the [PW12O40]3– anion is enhanced, in ethanol–water or acetone solution at pH < 8. Key words: 12-tungstophosphate heteropolyacid, decomposition behaviour, potentiometric titration, 31P NMR, preparation high performance liquid chromatography.

scholarly journals Protected Gold Nanoparticles with Thioethers and Amines As Surrogate Ligands

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
M. Rafiq H. Siddiqui
Keyword(s):  
Gold Nanoparticles ◽  
Variable Temperature ◽  
Size Control ◽  
Analytical Techniques ◽  
High Resolution Electron Microscopy ◽  
Phase Method ◽  
Two Phase ◽  
H Nmr ◽  
Resolution Electron ◽  
Vis Spectroscopy

Dodecyl sulfide, dodecyl amine, and hexylamine were shown to act as surrogate ligands (L) via metastable gold nanoparticles. By collating analytical and spectroscopic data obtained simultaneously, empirical formula Au24L was assigned. These impurity-free nanoparticles obtained in near quantitative yields showing exceptional gold assays (up to 98%Au) were prepared by a modification of the two-phase method. Replacement reactions on the Au24L showed that Au:L ratios may be increased (up to Au55:L (L= (H25C12)2S)) or decreased (Au12:L (L= H2NC12H25and H2NC6H13)) as desired. This work encompassing the role of analytical techniques used, that is, elemental analysis, variable temperature1H NMR, FAB mass spectrometry, UV-Vis spectroscopy, thin film X-ray diffraction, and high-resolution electron microscopy (HREM) has implications in the study of size control, purity, stability, and metal assays of gold nanoparticles.

Solvent-Loaded Microspheres for Permeability Enhancement in Heavy Crude Oil Reservoirs

2021 ◽  
Author(s):  
Cengiz Yegin ◽  
Cenk Temizel ◽  
Mustafa Akbulut
Keyword(s):  
Energy Demand ◽  
Fossil Fuels ◽  
Analytical Techniques ◽  
Recovery Factor ◽  
Low Permeability ◽  
Sand Column ◽  
Permeability Enhancement ◽  
Recovery Potential ◽  
Novel Approach ◽  
Vis Spectroscopy

ABSTRACT With their abundancy and high-quality, it is predicted that fossil fuels will remain as the main resource that will meet the global energy demand in the several upcoming decades. Developments in hydrocarbon recovery technologies, both from conventional and unconventional reservoirs, have substantially contributed to the overall production levels in recent years. However, recovery factors obtained by using the current methods are still considered to be insufficient, and the companies have been looking for new materials and methods to enhance the efficiency and amount of recovery. One of the major issues related to low recovery factors is low permeability of reservoirs. Existence of blockages in pore throats and high level of heterogeneity lowers the mobility of hydrocarbons. In this study, we discuss development of an innovative material to be used as an additive in reservoir injection fluids to remove pore blockages in order to enhance the recovery levels. This additive material is made of pressure-sensitive microspheres loaded with solvents, which can (i) easily disperse in the injection fluid and travel to the low-permeability regions, (ii) break under pressure and confinement to release solvents, and (iii) remove blockages by targeting surroundings, especially asphalt-based particles and grains. This approach relies on the breakage of microcapsules in the confined region and release of the solvents to target blockages in porous media. In other words, the developed microspheres improve permeability of reservoirs as a result of pressure- and confinement-dependent breakage and release of solvents. Preparation of these microspheres was achieved by the encapsulation of solvent (toluene) emulsions in silica-based solid shells. Structure and stability of the solvent-loaded microspheres were examined using a variety of analytical techniques including UV-vis spectroscopy, optical microscopy, scanning electron microscope (SEM) and dynamic light scattering (DLS). It was found that the prepared microspheres possessed smooth surfaces with shell thicknesses in the range of 100-150 nm. Additionally, sand column tests were performed to evaluate the recovery potential of injection fluids in presence of solvent-loaded microspheres. It was shown that the use of solvent encapsulated in microspheres doubled the recovery factor of heavy oil compared to that of free solvent dispersed in the injection fluid. Such enhancement in the recovery factor was related to the release of solvents in localized areas, i.e., confined regions, as a consequence of breakage of microspheres. This novel approach of delivering solvents to low-permeability regions provides a significant driving force to eliminate pore blockages to facilitate mobilization of hydrocarbons trapped in confined spaces.

Sign in / Sign up

Export Citation Format

Share Document