Investigation and radiometric determination of saturated and unsaturated aliphatic monocarboxylic acids and aromatic dicarboxylic acids

1973 ◽  
Vol 13 (1) ◽  
pp. 67-74
Author(s):  
Cs. Ömböly ◽  
T. Szarvas ◽  
G. Végh
Keyword(s):  
Dicarboxylic Acids ◽  
Monocarboxylic Acids ◽  
Aromatic Dicarboxylic Acids ◽  
Radiometric Determination

Methods for the Synthesis of Polyethereketone

2018 ◽  
Vol 935 ◽  
pp. 27-30
Author(s):  
K.T. Shakhmurzova ◽  
Zh.I. Kurdanova ◽  
Arthur E. Baikaziev ◽  
Karina Kh. Teunova ◽  
Azamat A. Zhansitov ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Aromatic Hydrocarbons ◽  
Electrophilic Substitution ◽  
Methylene Chloride ◽  
Dicarboxylic Acids ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Low Molecular Weight ◽  
Monocarboxylic Acids ◽  
Synthesis Time ◽  
Aromatic Dicarboxylic Acids

The data on the methods for the preparation of polyetherketones by electrophilic and nucleophilic methods are considered and generalized. It is shown that polyetherketones by electrophilic substitution are carried out as homopolycondensation aromatic monocarboxylic acids and their halides and polycondensation of polynuclear aromatic hydrocarbons with aromatic dicarboxylic acids or their halides, and phosgene in organic solvents (1,2-dichloroethane, methylene chloride, nitrobenzene and etc.) in the presence of Ziegler-Natt catalysts. However, this process has not found an industrial application in view of such disadvantages as low yield of the desired product, the formation of a polymer with low molecular weight, synthesis time (15-40 hours), the use of large amounts of catalyst, the complexity of polymer purification of it.

Screening and characterization of a novel reversible 4-hydroxyisophthalic acid decarboxylase from Cystobasidium slooffiae HTK3

2021 ◽  
Author(s):  
Riku Aono ◽  
Tomoya Yoshihara ◽  
Hotaka Nishida ◽  
Kuniki Kino
Keyword(s):  
Carboxylic Acids ◽  
Building Block ◽  
Acid Production ◽  
Dicarboxylic Acids ◽  
Acid Decarboxylase ◽  
Hydroxybenzoic Acid ◽  
Monocarboxylic Acids ◽  
Aromatic Dicarboxylic Acids

Abstract Owing to carboxylation activity, reversible decarboxylases can use CO2 as a C1-building block to produce useful carboxylic acids. Although many reversible decarboxylases can synthesize aromatic monocarboxylic acids, only a few reversible decarboxylases have been reported to date that catalyze the synthesis of aromatic dicarboxylic acids. In the present study, a reversible 4-hydroxyisophthalic acid decarboxylase was identified in Cystobasidium slooffiae HTK3. Furthermore, recombinant 4-hydroxyisophthalic acid decarboxylase was prepared, characterized, and used for 4-hydroxyisophthalic acid production from 4-hydroxybenzoic acid.

INFLUENCE OF DICARBOXYLIC ACIDS ON SOWING QUALITY OF SPRING BARLEY

1970 ◽  
pp. 22-25
Author(s):  
N. N. Loy ◽  
S. N. Gulina
Keyword(s):  
Organic Acids ◽  
Spring Barley ◽  
Dose Range ◽  
Dicarboxylic Acids ◽  
Rotary Machine ◽  
Working Solution ◽  
Negative Effect ◽  
Sprouted Seeds

The effect of presowing seed treatment on various concentrations of dicarboxylic (organic) acids on the sowing characteristics of spring barley has been studied. Seeds were treated with organic acids obtained by exposing cuttings to the radiation with a dose of 100 kGy and consequent hydrolysis, in concentrations: 1•10-7 %; 1•10-9; 1•10-11; 1•10-13 and 1•10-15 % on a laboratory rotary machine RVO-64 for one day before laying for germination. Distilled water was used for the control case. The rate of application of the working solution calculated as 10 liters / ton of seeds. Seeds were germinated in filter paper rolls in accordance with GOST 12038-84 requirements. The temperature was maintained at +24 ° C in the thermostat where the glasses with rolls were placed. For determination of germinative power and laboratory germination the sprouted seeds were evaluated after three and seven days, respectively. In laboratory experiments it was established that the treatment of barley seeds of varieties Zazersky 85, Nur and Vladimir with organic acids (OK) in different concentrations had both a stimulating and a negative effect. On the Zazersky 85 variety, in variants with acid concentrations of 1•10-9 and 1•10-11, an increase in germination energy (EP) by 2-4% and a significant decrease (by 3-4%) of laboratory germination (LV) of barley seeds were noted. On the Nur variety, the increase in EP was observed at 4% (concentration 1•10-11), LV and seed growth force (CPC) by 2-7% at a concentration of 1•10-7 and in the dose range 1•10-11 - 1•10-14 compared to the control values. On the grade of Vladimir, an increase in EP, LV, and CPC was found to increase by 1-6% at concentrations OK 1•10-7 and 1•10-13. It was shown that the treatment of seeds with acids led to an increase in the length of the germ in all studied varieties (by 3-9%) and dry biomass of 7-day-old seedlings - by 3-6%. Consequently, the treatment of seeds with a mixture of dicarboxylic acids has a stimulating effect on the sowing quality of spring barley.

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