scholarly journals Determination of molar refractions and Abraham descriptors for tris(acetylacetonato)chromium(iii), tris(acetylacetonato)iron(iii) and tris(acetylacetonato)cobalt(iii)

2017 ◽  
Vol 41 (23) ◽  
pp. 14259-14265 ◽  
Author(s):  
Michael H. Abraham ◽  
William E. Acree ◽  
Anthony F. Fucaloro ◽  
Andrew W. Zanella
Keyword(s):  
Physicochemical Properties ◽  
Chemical Properties

Descriptors for tris(acetylacetonato) complexes of Cr(iii), Fe(iii) and Co(iii) can be used to assess chemical properties of the complexes and to predict numerous physicochemical properties.

scholarly journals The Potential Corrosiveness of Soil Physico- Chemical Properties on Pipelines

2020 ◽  
pp. 99-108
Author(s):  
Eunice Asiboroko Odesiri-Eruteyan ◽  
Urhibo Voke Owarieta ◽  
Nnaji Praise Tochukwu ◽  
Efenudu Favour
Keyword(s):  
Physicochemical Properties ◽  
Chemical Properties ◽  
Soil Samples ◽  
Galvanized Steel ◽  
Soil Physicochemical Properties ◽  
Sulphate Content ◽  
Sulphate Chloride ◽  
Oil Spillage ◽  
Physico Chemical

Aim: The study was conducted to determine the potential corrosiveness of selected soil physicochemical properties on pipelines. Study Design: Soil samples were randomly collected around five pipeline locations with control from a farmland. Duration of Study: The study lasted for three months. Methodology: Standard methods were adopted in the collection of samples and the determination of the physicochemical properties of the samples. Results: Metallic pipelines undergo more regular corrosion because they are used in environments like soil where they are chemically unstable. Soil physicochemical properties such as soil moisture, texture, pH and temperature, sulphate, chloride, redox potential and resistivity were determined. The pH of the five soil samples was acidic (pH =4.0 – 6.5), The highest moisture content was 22.88% while the lowest was 9.84%. The soil samples the potential of being corrosive to the buried galvanized-steel and cast-iron pipes. Delta Steel Company (DSC) roundabout had the highest sulphate content of 724.13 mg/kg while the lowest was Oleh with 156.14 mg/kg. The highest percentage of Total Organic Carbon was 0.52% and the lowest was 0.40%. Conclusion: Besides pipeline vandalization, pipeline corrosion may likely be one of the major causes of oil spillage in localized underground pipelines within the region. There is, therefore, an urgent need for computerized sensors to assist in the monitoring of underground pipeline integrity in Nigeria.

Characteristics Of The Structure Formation Of Gypsum Binder Modified With Zinc Hydrosilicates

2020 ◽  
pp. 40-46
Keyword(s):  
Synergistic Effect ◽  
Physicochemical Properties ◽  
Structure Formation ◽  
Silicic Acid ◽  
Chemical Properties ◽  
Crystal Formation ◽  
Ability To Act ◽  
Chemical Factors ◽  
Sorption Characteristics

The authors' methodic for assessing the role of chemical and physic-chemical factors during the structure formation of gypsum stone is presented in the article. The methodic is also makes it possible to reveal the synergistic effect and to determine the ranges of variation of controls factors that ensure maximum values of such effect. The effect of a micro-sized modifier based on zinc hydro-silicates on the structure formation of building gypsum is analyzed and corresponding dependencies are found. It is shown that effects of influence of modifier on the properties of gypsum compositions are determined by chemical properties of modifier. Among the mentioned properties are sorption characteristics (which depend on the amount of silicic acid and its state) and physicochemical properties - the ability to act as a substrate during crystal formation. The proposed method can also be extended to other binding substances and materials. This article contributes to the understanding of the processes that occur during the structure formation of composites, which will make it possible to control the structure formation in the future, obtaining materials with a given set of properties.

THE IMPORTANCE OF THE RED BOOK OF SOILS FOR MONITORING AND JUSTIFICATION OF CONSERVATION MEASURES

2020 ◽  
Author(s):  
O.S. Bezuglova ◽  
Keyword(s):  
Chemical Properties ◽  
Natural State ◽  
Soil Maps ◽  
Rostov Region ◽  
Conservation Measures ◽  
Background Data ◽  
The Russian Federation ◽  
Physical And Chemical ◽  
And Chemical Properties

Rostov Region belongs to the highly protected natural territories characterized by the continuous plowing. There territories are the only reserves with the soils preserved in their natural state. However, these areas often lack detailed information about the soils quality and composition. Surveying soils on these territories is crucial for determination of their basic physical and chemical properties. The resulted compilation of soil maps could lay a foundation for creating the Red Book of Soils and the formation of a section in the soil-geographical database of the Russian Federation. Subsequently, such information can be used as a background data for the main types of soils in the region. It will be also valuable during monitoring and justification of conservation measures.

scholarly journals Physicochemical characterisation of kafirins extracted from sorghum grain and dried distillers grain with solubles related to their biomaterial functionality

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Umar Shah ◽  
Deepak Dwivedi ◽  
Mark Hackett ◽  
Hani Al-Salami ◽  
Ranjeet P. Utikar ◽  
...  
Keyword(s):  
Secondary Structure ◽  
Physicochemical Properties ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Chemical Properties ◽  
X Ray ◽  
Distillers Grain ◽  
Sorghum Grain ◽  
Dried Distillers Grain ◽  
Polypeptide Profile

AbstractKafirin, the hydrophobic prolamin storage protein in sorghum grain is enriched when the grain is used for bioethanol production to give dried distillers grain with solubles (DGGS) as a by-product. There is great interest in DDGS kafirin as a new source for biomaterials. There is however a lack of fundamental understanding of how the physicochemical properties of DDGS kafirin having been exposed to the high temperature conditions during ethanol production, compare to kafirin made directly from the grain. An understanding of these properties is required to catalyse the utilisation of DDGS kafirin for biomaterial applications. The aim of this study was to extract kafirin directly from sorghum grain and from DDGS derived from the same grain and, then perform a comparative investigation of the physicochemical properties of these kafirins in terms of: polypeptide profile by sodium-dodecyl sulphate polyacrylamide gel electrophoresis; secondary structure by Fourier transform infra-red spectroscopy and x-ray diffraction, self-assembly behaviour by small-angle x-ray scattering, surface morphology by scanning electron microscopy and surface chemical properties by energy dispersive x-ray spectroscopy. DDGS kafirin was found to have very similar polypeptide profile as grain kafirin but contained altered secondary structure with increased levels of β-sheets. The structure morphology showed surface fractals and surface elemental composition suggesting enhanced reactivity with possibility to endow interfacial wettability. These properties of DDGS kafirin may provide it with unique functionality and thus open up opportunities for it to be used as a novel food grade biomaterial.

scholarly journals Concurrent chromatographic determination of pseudoephedrine and loratadine from combination syrups and tablets

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Imad Osman Abu Reid
Keyword(s):  
Ammonium Acetate ◽  
Chemical Properties ◽  
Chromatographic Determination ◽  
Analytical Challenge ◽  
Intermediate Precision ◽  
Box Behnken Design ◽  
Complex Samples ◽  
System Suitability ◽  
Nonpolar Compounds

Abstract Background Chromatographic separation of polar and nonpolar compounds when presented in combined dosage forms has always been considered as great analytical challenge. Separation and retention of both polar and nonpolar compounds by the same stationary phase can be a useful approach for analyses of complex samples with such a difference in chemical properties. Loratadine (nonpolar) and pseudoephedrine (polar) are typical examples of this situation. Results The Box–Behnken design was used to optimize the separation process, an efficient separation of loratadine and pseudoephedrine was achieved within 6 min; employing a mixture of 16.0 mM ammonium acetate buffer (pH 4.5) and acetonitrile (23:77, v/v) as isocratic mobile phase, pumped at 1.0 mL/min through a Zorbax cyanopropyl column (250 mm × 4.6 mm, 5 μm), the analytes were detected at 250 nm. Under the same conditions, separation of sodium benzoate preservative co-formulated with the two analytes in syrup formulation was also achieved. The calibration curve demonstrated excellent linearity in the range of 24.6–123.2 μg/mL and 594.8–2974.0 μg/mL for loratadine and pseudoephedrine, respectively with determination coefficient (r2) > 0.999. Conclusion The method’s accuracy bias < 2.0%, repeatability and intermediate precision (%RSD < 2.0%) were verified. In addition, system suitability parameters were found within the acceptable limits. Satisfactory results were obtained upon the application of the validated method to the analysis of commercial tablet and syrup formulations.

scholarly journals Born out of Fire and Ice: Polymorph Studies of the Antiviral Famciclovir

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 129
Author(s):  
Liana Vella-Zarb ◽  
Ulrich Baisch
Keyword(s):  
Variable Temperature ◽  
Chemical Properties ◽  
Crystal Form ◽  
X Ray Diffraction ◽  
Crystal Forms ◽  
X Ray ◽  
Physical Chemical ◽  
Diffraction Patterns ◽  
Crystalline Forms

There is much interest and focus on solid forms of famciclovir. However, in spite of the abundance of reported differences in oral bioavailability, compressibility, and other physical–chemical properties of the various crystal forms of this drug, very little precise structural analysis is available in the literature to date. The form used in the commercial formulation is the anhydrous form I. Patents and patent applications report three different anhydrous crystalline forms on the basis of unindexed powder diffraction patterns. Single-crystal and variable-temperature X-ray diffraction experiments using the commercially available anhydrous form of famciclovir were carried out and led not only to the crystal structure determination of the anhydrous form I, but also to discovery of a new crystal form of anhydrous famciclovir from powder data.

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