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Application of Coal Rock Analysis in Coking Productions
Wu Xian Xi,
Chen Guo Qing,
Liu Bin Bin,
Wu Son
Issue:
Volume 8, Issue 1, February 2020
Pages:
1-5
Received:
4 January 2020
Accepted:
4 February 2020
Published:
18 February 2020
Abstract: In the coking industry, the variety and quality of single coal is the basis for influencing the quality of coal blending and ultimately the quality of coke products. Nowadays, some coking plants generally use industrial analysis methods to determine the quality of coal varieties and coal blending. However, using industrial analysis method alone cannot ensure that the variety quality identification of single coal and mixed coal is correct and reliable, therefore, there is no guarantee of coking coal blending and the final coking quality. Identifying coal by means of coal-rock analysis and distinguishing mixed coal can make up for the deficiency of industrial analysis in testing coal quality and types of coal. At the same time, according to the reflectivity of the vitrinite of coal can be additive, using synthetic coal reflectance distribution map to guide coal coking, can predict, improve and raise the quality of coke products. In this paper, some examples are given to identify coal type and distinguish mixed coal by reflectivity of coal vitrinite combined with industrial analysis method. At the same time, the method and example of applying synthetic coal reflectivity distribution map to guide coking coal to improve coke quality are also given. Finally noted, when using coal-rock method to guide coking and predict coke quality, it must be tested no arbitrary application.
Abstract: In the coking industry, the variety and quality of single coal is the basis for influencing the quality of coal blending and ultimately the quality of coke products. Nowadays, some coking plants generally use industrial analysis methods to determine the quality of coal varieties and coal blending. However, using industrial analysis method alone can...
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Research of Bioactive Chemical Markers in Trunk Bark Extracts of Anogeissus leiocarpa, a Traditional Herbal Remedy for Hypertension
Benjamin Ouedraogo,
Jules Yoda,
Felix Kini,
Jean Claude Ouedraogo,
Marius Lompo,
Sylvin Ouedraogo
Issue:
Volume 8, Issue 1, February 2020
Pages:
6-12
Received:
21 January 2020
Accepted:
10 February 2020
Published:
18 February 2020
Abstract: High blood pressure or hypertension is a public health problem in Burkina Faso. According to official statistics, its prevalence rate is estimated at 20%. The management of this disease is long-term with chronic treatments. This leads the population to resort to efficient, accessible and cheaper herbal medicines. Anogeissus leiocarpa is one of the plants used in traditional medicine for the treatment of hypertension in Burkina Faso. Earlier preclinical studies have proved the efficacy and safety of trunk bark extract. In this investigation, bioactive chemical marker phytocompounds are sought for the development, quality control and standardization of the antihypertensive drug based on this plant. The extracts of this plant are prepared by decoction from trunk bark powder and then fractionated successively with solvents in order of increasing polarity (n-hexane, dichloromethane, ethyl acetate and 1-butanol). The fractions obtained are subjected to phytochemical screening. The antioxidant properties of the different extracts have also been studied since the chemical species known as free radicals, which cause oxidative stress, are related to hypertension. The evaluation of the contents of total phenolic compounds and total flavonoids, which would have antihypertensive properties, was carried out according to the method using Folin-Ciocalteu. The highest total phenolic and total flavonoid contents were obtained with the ethyl acetate fraction (89.52 mg tannic acid equivalent/g dry extract and 70.87 mg quercetin equivalent/g dry extract for flavonoids). The best antioxidant power is also obtained with the ethyl acetate fraction (IC50: 6.93µg /mL). Standardization tests using analytical methods have identified three compounds A, B and C whose structure determination is in progress. These compounds could be used as markers for quality control of the prototype antihypertensive phytodrugs developed.
Abstract: High blood pressure or hypertension is a public health problem in Burkina Faso. According to official statistics, its prevalence rate is estimated at 20%. The management of this disease is long-term with chronic treatments. This leads the population to resort to efficient, accessible and cheaper herbal medicines. Anogeissus leiocarpa is one of the ...
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Phytochemical Composition, Biological Activities of Croton lobatus L. Leaves, Hydrolysis Effect on Activities and Chemical Composition
Marthe Dominique Chodaton-Zinsou,
Fidèle Mahoudo Assogba,
Eléonore Yayi-Ladékan,
Fernand Gbaguidi,
Mansourou Moudachirou,
Joachim Djimon Gbénou
Issue:
Volume 8, Issue 1, February 2020
Pages:
13-22
Received:
5 February 2020
Accepted:
27 February 2020
Published:
10 March 2020
Abstract: Croton lobatus L. is medicinal plant widely used in traditional medicine, but little known in literature for its biological properties. Aims were to study its phytochemical composition and some biological properties and influence of acid hydrolysis on biological activities and chemical composition of Croton lobatus L. extracts. Successive extractions with solvents of increasing polarity (cyclohexane, ethyl acetate, and methanol) were carried out on powder of Croton lobatus L. leaves. Evaluation of xanthine oxidase, acetylcholinesterase, 5-lipoxygenase and α-amylase inhibitions, antioxidant activity was performed. Acid hydrolysis effect was evaluated by comparison of chemical composition and xanthine oxidase, α-amylase inhibition activities of hydrolyzed and unhydrolyzed extracts. Results showed that at 50 mg/L Croton lobatus L. has very small antioxidant activity (3.4 - 4.9%), small inhibitory activity of 5-lipoxygenase (6.3-6.9%), inhibitory activity of acetylcholinesterase between (2.7 - 31.3%), moderate inhibitory activity of α-amylase (52.8 - 64.3%), moderate inhibitory activity of xanthine oxidase (22.2 - 62.6%). Croton lobatus L. could be used in diabetes and gout treatments, given results of α-amylase inhibition and xanthine oxidase. Acid hydrolysis has negative effect on process of xanthine oxidase inhibition and on chemical composition.
Abstract: Croton lobatus L. is medicinal plant widely used in traditional medicine, but little known in literature for its biological properties. Aims were to study its phytochemical composition and some biological properties and influence of acid hydrolysis on biological activities and chemical composition of Croton lobatus L. extracts. Successive extractio...
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Potentiometric Studies of Stability Constants and Speciation of Binary and Ternary Complexes of Metal (II) Ions with Amino Acids and Thiobarbituric Acid
Kayode Taiwo Ishola,
Mary Adelaide Oladipo,
Omobola Ajibike Odedokun,
Oladapo Tunde Olanipekun
Issue:
Volume 8, Issue 1, February 2020
Pages:
23-30
Received:
29 February 2020
Accepted:
19 March 2020
Published:
13 April 2020
Abstract: Several chelating agents have been widely used as scavengers to transport metals to or away from vulnerable sites due to their ability to form stable complexes with different metal ions. Many of the chelating agents have been reported to be toxic, non-biodegradable and inflexible for the recovery of bound metal ions. The inherent drawbacks with these chelating agents necessitate a search for their replacement. Therefore, the extent of coordination of L-tyrosine, L-histidine (secondary ligands) and Thiobarbituric acid (primary ligand) with Co(II), Cu(II) and Pb(II) in an aqueous medium at 27°C and 35°C has been examined potentiometrically with ionic strength maintained by 0.02M NaNO3. The potentiometric equilibrium measurements showed that the ligands formed binary and ternary complexes with the metal ions. Ternary complexes were formed by simultaneous mechanisms and they were found to be more stable than the corresponding binary complexes. The order of stability was found to increase with an increase in the covalent index of the metal ions and decrease with increase in temperature. Speciation diagram showed the variation in stability constants of the binary and ternary complexes as the function of pH. The ligands exhibited high coordinating properties and could be used as metal scavengers for transportation of metals to or away from vulnerable sites. The binary metal complexes could be applied as a medium of transporting chemotherapeutic drugs to target sites or detoxifying poisonous substances which possesses donor atoms with chelating capability.
Abstract: Several chelating agents have been widely used as scavengers to transport metals to or away from vulnerable sites due to their ability to form stable complexes with different metal ions. Many of the chelating agents have been reported to be toxic, non-biodegradable and inflexible for the recovery of bound metal ions. The inherent drawbacks with the...
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