Thermodynamic parameters for the basic ionization of some cyclic amines in water

1976 ◽  
Vol 54 (22) ◽  
pp. 3607-3613 ◽  
Author(s):  
Sheila Teresa Lobo ◽  
Tanikella S. S. R. Murty ◽  
Ross Elmore Robertson
Keyword(s):  
Thermodynamic Parameters ◽  
Dilution Method ◽  
Ammonium Ions ◽  
Cyclic Amines ◽  
Basic Dissociation ◽  
Acid Ionization

The thermodynamic parameters defining the basic dissociation in water of diethylamine, cyclohexylamine, piperidine, and quinuclidine have been determined by a dilution method based on conductance measurements. The values of ΔSa0 and ΔCpa0 for the acid ionization of the corresponding ammonium ions at 25 °C are ΔSa0 −8.08, −1.24, −8.51, −13.65 cal deg−1 mol−1 and ΔCpa0 13.9, −2.7, 18.0, 4.2 cal deg−1 mol−1. The relation between these derived values and solvation changes are discussed, the apparent anomalous values of ΔCpa0 for cyclohexylamine and quinuclidine being noted, but not rationalized.

Solvent effect on the solution, ionization, and structure of aminosulfonic acids

1988 ◽  
Vol 66 (12) ◽  
pp. 3038-3043 ◽  
Author(s):  
Robert L. Benoit ◽  
Danielle Boulet ◽  
Monique Fréchette
Keyword(s):  
Solvent Effect ◽  
Thermodynamic Parameters ◽  
Enthalpies Of Solution ◽  
Ammonium Ions ◽  
Sulfonic Acids ◽  
Aliphatic Acids ◽  
Calorimetric Methods ◽  
Potentiometric And Calorimetric Methods

We have determined thermodynamic parameters for the solution and ionization in dimethylsulfoxide and water of four aminosulfonic acids: NH2(CH2)nSO3H with n = 0,1, and 2, and NH2C6H4SO3H. Potentiometric and calorimetric methods were used. The solubilities of the four acids in Me2SO are either nearly equal to or lower than in water, but the enthalpies of solution are 15–40 kJ mol−1 more exothermic in Me2SO. The three aliphatic acids are much weaker (2.1 ≤ ΔpKa ≤ 5.5) in Me2SO than in water and their heats of ionization are some 30 kJ mol−1 more endothermic in Me2SO. The discussion of our results is based on comparisons with corresponding data for related substituted amines and ammonium ions, and sulfonic acids and sulfonate ions. We conclude that the four aminosulfonic acids are mostly present as zwitterions in Me2SO just as in water.

Thermodynamic parameters for the basic ionization of some cyclic amines in water

1977 ◽  
Vol 55 (8) ◽  
pp. 1436-1436
Author(s):  
Sheila Teresa Lobo ◽  
Tanikella S. S. R. Murty ◽  
Ross Elmore Robertson
Keyword(s):  
Thermodynamic Parameters ◽  
Cyclic Amines

not available

Models of Thermodynamic Properties of Prominences

1979 ◽  
Vol 44 ◽  
pp. 349-355
Author(s):  
R.W. Milkey
Keyword(s):  
Thermodynamic Properties ◽  
Mass Transport ◽  
Emission Spectrum ◽  
Thermodynamic Parameters ◽  
Working Group ◽  
Physical Processes ◽  
Theoretical Concepts ◽  
Group 3 ◽  
Observational Techniques

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.

Isolation and Diagnosis of Fungi from Samples of Spices in the City of Nasiriya

2020 ◽  
pp. 7-9
Keyword(s):  
Chronic Diseases ◽  
Dilution Method ◽  
Local Markets ◽  
White Pepper ◽  
Black And White ◽  
Different Types ◽  
Potential Risks ◽  
The City ◽  
Isolated Species

Examination of (35) samples of spices obtained from local markets for the purposes of isolating and diagnosing fungi growing on them. Anine isolates belonging to 13 different types of fungi were diagnosed by the standard dilution method with three replications, and it has been observed that the most samples from which the fungi were isolated is ginger. It was found that the most isolated species of fungi are Penicillium, Aspergillus, and Rizupes spp. A rare colony of fungi was observed, which indicates contamination of the spices under study with the fungus. The present study aims to identify the potential risks of the presence of fungi in spices and what may result from mycotoxins that may be the cause of many chronic diseases as a result of using these spices in large quantities. The study recommends limiting the use of contaminated spices, especially ginger, in preparing food and its uses, in addition to other types such as cloves, black and white pepper, and other types of spices found in the local markets, especially the expired ones.

ON THE VALUE OF SOME PARAMETERS OF ADRENOCORTICAL GLUCOCORTICOID FUNCTION

1963 ◽  
Vol 44 (4) ◽  
pp. 499-504 ◽  
Author(s):  
M. Van Der Straeten ◽  
A. Vermeulen ◽  
N. Orie ◽  
P. Regniers
Keyword(s):  
Urinary Excretion ◽  
Adrenal Cortex ◽  
Isotope Dilution ◽  
Isotope Dilution Method ◽  
Dilution Method ◽  
Steroid Excretion ◽  
Colorimetric Methods

ABSTRACT The authors studied the correlation between cortisol production, as measured by an isotope dilution method, and the urinary excretion of total and free Porter-Silber chromogens, as well as of 17-ketogenic steroids. Although a significant correlation exists between total Porter-Silber chromogens, 17-ketogenic steroid excretion and cortisol production, discrepancies are occasionally observed. Hence, different colorimetric methods should be used to assess the glucocorticoid activity of the adrenal cortex.

ALDOSTERONE STIMULATION IN VITRO

1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Ammonium Chloride ◽  
Human Urine ◽  
Incubation Medium ◽  
The Other ◽  
Ammonium Ions ◽  
Response Curves ◽  
Urine Extract ◽  
Similar Dose ◽  
Aldosterone Production

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.

Sorption of Heavy Metals by Bed Silts in the Presence of Ammonium Ions

2016 ◽  
Vol 38 (2) ◽  
pp. 96-100
Author(s):  
V. Shkapenko ◽  
V. Kadoshnikov ◽  
E. Musich ◽  
I. Pisanskaya
Keyword(s):  
Heavy Metals ◽  
Ammonium Ions

Evaluation of antimicrobial potential of some spices from apiaceae sold in herbal shops

2019 ◽  
Author(s):  
Alev ONDER ◽  
Suna Sibel GURPINAR, Mujde ERYILMAZ ◽  
Bayram Kagan AKAY, Ahsen Sevde CINAR
Keyword(s):  
Antimicrobial Activity ◽  
Daucus Carota ◽  
Antimicrobial Effect ◽  
Coriandrum Sativum ◽  
Apium Graveolens ◽  
Dilution Method ◽  
Anethum Graveolens ◽  
Foeniculum Vulgare ◽  
Pimpinella Anisum ◽  
Hexane Extracts

Spices are a part of the plants used for many purposes as preservatives and as colorants in foods or as medicinal intention. Main aim of the present research was to estimate the potential antimicrobial activity of some spices from Apiaceae family such as Amni visnaga (Diş otu, Hıltan), Anethum graveolens (Dereotu), Apium graveolens (Kereviz), Coriandrum sativum (Kişniş), Cuminum cyminum (Kimyon), Daucus carota (Havuç), Foeniculum vulgare (Rezene), Petroselinum sativum (Maydanoz), Pimpinella anisum (Anason). Thus, the fruits of the plants are used in the experiments. The fruits have been extracted by n-hexane, and all extracts have been subjected to TLC (Thin Layer Chromatography). The n-hexane extracts were screened for their potential in vitro antibacterial activity against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 13883, Pseudomonas aeruginosa ATCC 27853 and antifungal activity against Candida albicans ATCC 10231 by microbroth dilution method. The hexane extracts of the fruits of Coriandrum sativum, Anethum graveolens, Daucus carota, and Pimpinella anisum did not show antimicrobial activity against tested microorganisms. Except these, the other extracts having MIC values of 2.5-5-10 mg/mL exhibited antimicrobial effect against some tested microorganisms. These results demonstrate that the extracts which have an antimicrobial effect can probably play a role as an antimicrobial agent owing to their nonpolar components which are accumulated to the n-hexane extracts.

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