French-Ukrainian Journal of Chemistry
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Corrosion Inhibition, Adsorption and Thermodynamic Properties of Poly (Sodium 4-Styrenesulfonate) on Carbon Steel in Phosphoric Acid Medium
Get PDFThe use of polymers as corrosion inhibitors has attracted much attention due to their low prices, inherent stability, availability and cost-effectiveness. The corrosion inhibiting effect of poly(sodium-4-styrenesulfonate) on carbon steel in phosphoric acid solution has been investigated using weight loss and scanning electron microscopy techniques (SEM) and theoretical calculations based on density functional theory (DFT). In the presence of 1.0×10-3 mol/L of inhibitor, a maximum inhibition effect of 98.06 % was observed. The influence of the concentration of the inhibitor, the temperature of the solution and the immersion time on the corrosion of carbon steel was investigated. Activation parameters such as activation energy (Eact), activation enthalpy (ΔHact), activation entropy (ΔSact), heat of adsorption (Qads) and adsorption free energy (ΔGads) were evaluated based on the effect of temperature on the corrosion and inhibition processes. It was found that the adsorption behaviour of poly(sodium-4-styrenesulfonate) (PSS) follows the Langmuir isotherm and the free energy change values indicate mixed chemical and physical adsorption on the carbon steel surface. The results obtained with the different methods agree well
Features of Indicators of Blood General Clinical Analysis and the Summary Analysis of an Organism’s General Reactivity at Chronic Inflammatory Process
Get PDFInflammatory diseases cause health disorders which result in a reduction of the population. That is why this medical problem is considered to be a very important one. The human immune system is responsible for protecting the body from infections of various origins, while inducing chronic inflammation (characterized by a long, often invisible course) which can result in proneness to recurrence, complications and resistance to therapy. The authors of the article analyzed and proved that there are immune status shifts in patients with chronic nonspecific inflammatory processes depending on the pathogen, phase and level of damage
Physical and Mechanical Properties of Fine-Grained Concrete Produced using Water Purified by Natural Adsorbents
Get PDFThe main part of drinking water consumption falls on powerful industrial facilities, however, the requirements for water used in technological processes are much lower than for drinking water. This work has shown that water contaminated with sulfates, after purification with natural adsorbents, comes up to the requirements of the standard. Determination of the initial and residual concentration of the pollutant in the solution was carried out through the control of electrical parameters, the so-called conductivity method. The purified solutions were used for the production of fine-grained concrete and the strength of the finished products was determined on the 28th day of hardening. The suitability of such solutions for use in the concrete industry was established not only from the point of view of suitability according to standards but also from the point of view of ensuring the required strength
Cheminformatics: A Patentometric Analysis
Get PDFCheminformatics has entrenched itself as a core discipline within chemistry, biology, and allied sciences, more particularly in the field of Drug Design Discovery and Development. The article begins with a patent analysis of the progressing field of cheminformatics from 1996 to early 2021 using the Relecura and Lens patent database. It proceeds with a description of patents in various domains and aspects. The eye-catching mind map shows the landscape of cheminformatics patent search. The results reveal the star rating-wise patent counts and the trends in the sub-technological research areas. At the end of the article, quantum clustering and eminent directions towards the future of cheminformatics have been discussed. This study would provide the directions to academicians, techno enthusiasts, researchers, stakeholders, or investors and helps increase the awareness of the potential of cheminformatics and quantum clustering
Complexation of 1,3-dihetaryl-5-phenyl-2-pyrazoline Derivatives with Polyvalent Metal Ions: Quantum Chemical Modeling and Experimental Investigation
Get PDF1,3,5-Triaryl-2-pyrazoline derivatives with a pyridine ring in position 1 and 2-benzimidazolyl or 2-benzothiazolyl bicycles in position 3 were synthesized. Spectral properties in solvents of similar polarity, i.e. aprotic acetonitrile and in protic methanol, were studied, complexation with cadmium and mercury ions in acetonitrile was elucidated as well. Quantum-chemical modeling with application of the elements of Bader's atoms-in-molecules (AIM) theory of the title molecules conformational structure and 1:1 stoichiometry complexes formed with polyvalent metals of various nature (Mg, Zn, Cd, Pb, Hg, Ba) was conducted. The principal possibility of “nitrogen-sulfur” switching of the metal ions binding sites for the benzothiazole derivative was revealed, and makes possible to classify this compound as “smart ligand”
Two New Pentacyclic Triterpenoids, an Alkaloid and a Long-chain Fatty Acid from Albizia Coriaria (Welw ex. Oliver)
Get PDFHerein, we report the occurrence of four new compounds in ethanolic extract of Albizia coriaria Welw ex. Oliver leaves along with other compounds previously reported in this species. The compounds were isolated and characterized using column chromatography, Fourier Transform Infrared (FTIR) and gas chromatography/mass spectrometry. FTIR spectrum of the extract showed phenolic OH stretching (3362.30 cm-1), C=O (1660.08 cm-1), CO stretching (1369.46 cm-1 and 1319.00 cm-1) and CN stretch (1072.44 cm-1) which confirmed the presence of alcohols, carboxylic acids and nitrogen-containing compounds. Oleanolic acid (1), oleanolic acid acetate (2), pterin-6-carboxylic acid (3), undecanol (4), betulinic acid (5), betulin (6) and benzyl alcohol (7) were tentatively identified in the extract. Compounds 1-4 are being reported for the first time in Albizia coriaria
Isoflavonoids Modified with Azole Heterocycles with Three Heteroatoms
Get PDFHeterocycle modified chromones are attracting increasing attention as novel potential therapeutic agents due to their effective bioactivities and low toxicity. This review describes all strategies and versatile synthons that have been developed for the synthesis of isoflavone heterocyclic analogs containing isolated 5-member heterocyclic rings with three identical or different heteroatoms. Their biological activity is also presented
Concentrations and Health Risk Assessment of Potentially Toxic Elements in Medicinal Herbs from Northern Nigeria
Get PDFThe concentrations of potentially toxic elements (Fe, Cd, Pb, Cu, Ni, Cr, and Zn) in most consumed medicinal herbs in Northern Nigeria were analyzed using Atomic Absorption Spectrometry (AAS). Twenty medicinal herbs were selected and purchased from the local markets. The findings of the study revealed that the investigated herb samples contained considerable levels of elements; Cu, Fe, Pb, Cd, and Cr above the permissible limits. The health risk observed as hazard index (HI) indicated that values were >1, in some samples. Therefore, the consumption of these studied medicinal herbs should be monitored to prevent the health implication due to a high level of these elements in the medicinal herbs
Removal of Phosphates in Aqueous Solution by Adsorption on Calcium Oxide
Get PDFThe aim of this work is the removal of phosphates from an aqueous solution by adsorption on a new, inexpensive adsorbent, calcium oxide. We have also shown interest in the choice of removal method, which is adsorption. The kinetic study of the removal of phosphate ions by adsorption on calcium oxide allowed us to calculate the value of adsorption capacity as a function of the parameters affecting adsorption: Amount of adsorbent, initial concentration of phosphate ion solution, pH of the mixture and temperature. The study of adsorption isotherms showed that the Freundlich model is the most appropriate for the phenomenon of phosphate ion adsorption. Modeling of the kinetic data by the pseudo-first order and pseudo-second order equations shows that the adsorption process is best described by the second order equation. Thermodynamic parameters such as enthalpy ΔH°, entropy ΔS° and free enthalpy ΔG° were also evaluated to determine the nature of adsorption. The results show that the adsorption process is a spontaneous and endothermic physisorption
Physicochemical Quality of Water from Chuho Springs, Kisoro District, Uganda
Get PDFIn the current study, water from Chuho springs used as the main water source in Kisoro municipality, Uganda were assessed for their suitability as drinking water. The temperature, turbidity, conductivity, total dissolved solids, dissolved oxygen, biological oxygen demand, total hardness, total alkalinity, calcium, magnesium, phosphates, iron, copper, arsenic, chlorides and the fluoride content of the water samples were determined. Not all the parameters met World Health Organizations’ guidelines for drinking water. Temperature, dissolved oxygen and fluorides were outside the recommended limits of 15 ℃, 10-12 mg/L and 1.5 mg/L, respectively. Further studies should assess the microbiological and sanitary profile of the springs