Characterization of Molecular Arrangement of Long‐chain Ferrocenyl Derivatives Having Asymmetric Carbon by Method of Organized Molecular Films and Formation of Its Helical Nanofibers

2021 ◽  
Vol 6 (9) ◽  
pp. 2198-2209
Author(s):  
Yusuke Kimura ◽  
Yuki Mashiyama ◽  
Haruka Maruyama ◽  
Youhei Kawabata ◽  
Tatsuro Kijima ◽  
...  
Keyword(s):  
Molecular Films ◽  
Molecular Arrangement ◽  
Asymmetric Carbon ◽  
Long Chain

Separation and Characterization of Standard Propoxyphene Diastereomers and Their Determination in Pharmaceutical and Illicit Preparations

1981 ◽  
Vol 64 (4) ◽  
pp. 875-883
Author(s):  
Shiv K Soni ◽  
Daniel Van Gelder
Keyword(s):  
High Pressure ◽  
Optical Isomers ◽  
Gold Chloride ◽  
Melting Points ◽  
Eutectic Melting ◽  
Racemic Mixtures ◽  
The Individual ◽  
Isomeric Mixtures ◽  
Asymmetric Carbon

Abstract Due to the existence of 2 asymmetric carbon atoms in: the propoxyphene molecule, there are 4 diastereomers: alpha dextro, alpha levo, beta dextro, and beta levo. Only α-d-propoxyphene is included under the federal Controlled Substances Act. Baseline separations of propoxyphene from various incipients (aspirin, caffeine, phenacetin, and acetaminophen) present in pharmaceutical and illicit preparations, and between the alpha and beta diastereomers, were achieved by high pressure liquid chromatography. The column eluant was collected and propoxyphene was extracted. The optical isomers were differentiated and characterized by melting points and by chemical microcrystalline tests. Using hot stage thermomicroscopy, the eutectic melting points of binary isomeric mixtures of propoxyphene bases and salts were found to be depressed about 10° and 15-30°C, respectively, below the individual isomer melting points. The characteristic microcrystals formed with the alpha racemic mixtures by using a glycerin-aqueous gold chloride reagent were not produced by the beta racemic mixtures.

scholarly journals Synthesis and Characterization of Partially Renewable Oleic Acid-Based Ionomers for Proton Exchange Membranes

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 130
Author(s):  
Carlos Corona-García ◽  
Alejandro Onchi ◽  
Arlette A. Santiago ◽  
Araceli Martínez ◽  
Daniella Esperanza Pacheco-Catalán ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Proton Conductivity ◽  
Electrochemical Impedance ◽  
Proton Exchange Membranes ◽  
Proton Exchange ◽  
Molar Ratio ◽  
Aromatic Diamines ◽  
Chemical Structures ◽  
Long Chain

The future availability of synthetic polymers is compromised due to the continuous depletion of fossil reserves; thus, the quest for sustainable and eco-friendly specialty polymers is of the utmost importance to ensure our lifestyle. In this regard, this study reports on the use of oleic acid as a renewable source to develop new ionomers intended for proton exchange membranes. Firstly, the cross-metathesis of oleic acid was conducted to yield a renewable and unsaturated long-chain aliphatic dicarboxylic acid, which was further subjected to polycondensation reactions with two aromatic diamines, 4,4′-(hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline and 4,4′-diamino-2,2′-stilbenedisulfonic acid, as comonomers for the synthesis of a series of partially renewable aromatic-aliphatic polyamides with an increasing degree of sulfonation (DS). The polymer chemical structures were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 19F NMR) spectroscopy, which revealed that the DS was effectively tailored by adjusting the feed molar ratio of the diamines. Next, we performed a study involving the ion exchange capacity, the water uptake, and the proton conductivity in membranes prepared from these partially renewable long-chain polyamides, along with a thorough characterization of the thermomechanical and physical properties. The highest value of the proton conductivity determined by electrochemical impedance spectroscopy (EIS) was found to be 1.55 mS cm−1 at 30 °C after activation of the polymer membrane.

Synthesis and characterization of hydrophobic long-chain fatty acylated cellulose and its self-assembled nanoparticles

2012 ◽  
Vol 69 (4) ◽  
pp. 389-403 ◽  
Author(s):  
Yanzhu Guo ◽  
Xiaohui Wang ◽  
Dong Li ◽  
Hong Du ◽  
Xiaoying Wang ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Self Assembled ◽  
Long Chain

Synthesis and characterization of some long-chain diesters with branched or bulky moieties

2000 ◽  
Vol 77 (8) ◽  
pp. 865-871 ◽  
Author(s):  
Gerhard Knothe ◽  
Robert O. Dunn ◽  
Michael W. Shockley ◽  
Marvin O. Bagby
Keyword(s):  
Synthesis And Characterization ◽  
Long Chain

Characterization of long chain branching: Dilution rheology of industrial polyethylenes

2002 ◽  
Vol 46 (2) ◽  
pp. 401-426 ◽  
Author(s):  
B. J. Crosby ◽  
M. Mangnus ◽  
W. de Groot ◽  
R. Daniels ◽  
T. C. B. McLeish
Keyword(s):  
Chain Branching ◽  
Long Chain Branching ◽  
Long Chain

Synthesis and characterization of sodium meta-autunite, Na[UO2PO4]·3H2O

2005 ◽  
Vol 93 (7) ◽  
Author(s):  
D. M. Wellman ◽  
J. G. Catalano ◽  
J. P. Icenhower ◽  
A. P. Gamerdinger
Keyword(s):  
Synthesis And Characterization ◽  
Mineral Phase ◽  
Sodium Polyphosphate ◽  
Uranium Phosphate ◽  
Long Chain

AbstractLong-chain sodium polyphosphate compounds have been recently proposed as a ‘time-released’ source of phosphate for precipitation of uranium-phosphate minerals. Elevated sodium concentrations presented by this technique promote the formation of sodium autunite relative to the more common calcium autunite mineral phase. In order to evaluate sodium autunite minerals as a long-term ‘sink’ for

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