Chemical Science International Journal
EISSN : 2456-706X
Published by: Sciencedomain International (10.9734)
Total articles ≅ 350
Latest articles in this journal
Chemical Science International Journal pp 26-40; https://doi.org/10.9734/csji/2022/v31i130274
Pollutants is constantly introduced into the aquatic environment primarily due to amplified industrial activity, technical development, growing human population and mistreatment of natural resources, agriculture and domestic wastes run-off. Among these pollutants, Organochlorine Pesticides and some trace metals such as Lead (Pb)Mercury(Hg)and Cadmium (Cd) are found as one of the most hazardous because of their toxicity to organisms This study investigate the levels of organochlorine pesticide (OCP) residues and Trace Metal concentration in Well and Stream waters from Agricultural Farm Settlement in Ile-Oluji Ondo State. Ten (10) samples each of 1 Liter Well and Stream waters were collected randomly for trace metal analysis and another Ten (10) samples each of 2.5 Liter Well and Stream waters were collected for Organochlorine Pesticide analysis within the Farm Settlement and its vicinity. Quantitative determination of the OCPs was determined using Gas Chromatography-Mass Spectrometer after liquid-liquid extraction with (v/v) ethyl acetate/dichloromethane mixture and the Trace Metal was determined using Atomic Absorption Spectrophotometer. The results show that organochlorine pesticide residues were not detected in all the well water samples except for AKN where Heptachlor was detected in the concentration of 0.11 mg/L while all samples from the stream were contaminated with the Organochrorine pesticides at appreciably higher concentration than WHO standards. The results also shows that all the trace metals analyzed for are present except for some well samples where Lead concentration is below the detection limit. The mean concentration of some of the sampling sites were below the permissible limit for WHO while some are higher than the permissible limit.
Chemical Science International Journal pp 15-25; https://doi.org/10.9734/csji/2022/v31i130273
The aim of the present study to clarify the phytochemical constituents of Rumex plants, extraction, separation and structural identification of chemical components, provide theoretical support and scientific basis for its traditional use, further expand the application scope of traditional medicinal plant resources in Uzbekistan, and develop its potential value. Three known anthraquinone derivatives has been isolated from the chloroform fraction extract of Rumex pamiricus roots and two known compounds were separated from the ethyl acetate fraction extract of Rumex conglomeratus roots. Their structures were elucidated by extensive spectroscopic evidence and chemical methods. Qualitative analyses of major phenolics by TLC analysis were also evaluated. The ester oil from the aerial parts of Rumex confertus and Rumex pamiricus, the gasoline, chloroform, ethyl acetate and butanol extracts of Rumex pamiricus aerial part and alcohol extract of Rumex pamiricus roots were tested in vitro for antimicrobial activity. This study aimed to determine the in vitro antimicrobial activity of the medicinal plants traditionally used in Uzbekistan against the microbial strains associated with infectious diseases.
Chemical Science International Journal pp 8-14; https://doi.org/10.9734/csji/2022/v31i130272
In article, we have reported the thermodynamic Van’t Hoff equation in study of dissociation process of solute benzoic acid into water solvent at ordinary temperature in between of 288 K to 318 K. At this temperature range, the value of dissociation constant (Kc) of that acid is being to found as -4.169, -4.045, -3.993, -3.885, -3.848 and -3.788, for given concentrations of NaCl (sodium chloride) volume as its six ionic strength of 0.00, 0.05, 0.10, 0.30, 0.40 and 0.50 M, respectively, which are titrimetrically analyzed with 0.05 M basic NaOH (sodium hydroxide) solution. The pH value of each solution is measured by using of digital pH-meter as well. Here, observation reported that the pH value of benzoic acid into water at that range of temperature is being inversely related to concentrations of NaCl. In graph, a value of benzoic acid with there ionic strength (I) is plotted versus equilibrium dissociation constant (Kc) at specific 298 K, have shown the dissociation of acid into water is increases as increase the ionic strength. But, comparatively, the graph for increasing temperature range to thermodynamic dissociation constant (Ka) have shown that the dissociation is not always increases as if increases temperature.
Chemical Science International Journal pp 1-7; https://doi.org/10.9734/csji/2022/v31i130271
Phytochemical screening remains the most effective method for identifying and screening medically active components of plant. This research work studied the phytochemical screening, toxicity profile and antibacterial activity of the stem bark of Andira inermis using four different extracts by varying the polarity of the solvents; n-hexane, chloroform, ethyl acetateand methanol. The screening revealed the presence of alkaloids and carbohydrates in all extracts, tannins and saponins were not detected in chloroform and n-hexane extract, glycoside was also not detected in the chloroform extract. The toxicity profile in vivo studies using the Lorke’s method revealed no significance changes in the body weight of the albino rats, and the LD50 was higher than 5000mg/kg. However, there was a significant changes in behavior of the albino rats such as, fatigue, diarrhea, restlessness etc at 1600 mg/kg, 2900mg/kg and 5000mg/kg doses of the extracts respectively. Antimicrobial studies was evaluated with four (4) each of different bacteria and fungi. The results revealed ethylacetate and chloroform (moderately polar solvents) extracts to be more active against both bacteria and fungi but the methanol (highly polar) and hexane (highly non polar) extracts possessed less activities as compared with the other extracts at 15, 20, 30 and 40% concentrations.
Published: 28 December 2021
Chemical Science International Journal pp 33-38; https://doi.org/10.9734/csji/2021/v30i1230269
An experiment was carried out to study the nutritional requirement and response of different physiological parameters viz., temperature and pH on mycelial growth of different isolates of Alternaria porri (Ellis) Cif causing purple blotch of onion. The five different pH levels, temperature, carbon sources and nitrogen sources were tested for their effect on mycelial growth and sporulation of A. porri. The results showed that the maximum mycelial growth and sporulation of A. porri was observed at pH 7.0 and minimum at pH 9.0. In temperature range the maximum mycelial growth and sporulation was recorded at 30 oC and minimum at 10 o. The mycelial growth of A. porri was different on Czapek’s dox agar basal medium with different carbon sources. Maximum radial growth was observed on maltose followed by sucrose and minimum on dextrose maltose. The mycelial growth of A. porri grown on varied Czapek’s dox agar basal medium with different nitrogen sources. Maximum mycelial growth and sporulation was observed on potassium nitrate followed by sodium nitrate and minimum on urea, respectively.
Published: 28 December 2021
Chemical Science International Journal pp 39-50; https://doi.org/10.9734/csji/2021/v30i1230270
Moringa husks and Jatropha cacus were evaluated using decoloration of methylene blue for the removal of lead (Pb) and cadmium (Cd) from water sample. The results showed that Moringa has better properties: physicochemical properties: pH, moisture content (%), ash content (%), carbon content (%), volatile matter (%), surface area (m2/g), electrical conductivity (µs/cm), bulk and density (g/L), 6.4, 14, 4, 63.26, 10, 787, 867 and 400 respectively, decoloration of methylene blue at 10 to 90 minutes ranges from 11 to 87% , Pb and Cd adsorption capacity 55.7 and 86, % degradation 85 and 92 than the Jatropha cacus 50.2 and 55.2, 78 and 83 respectively. The Moringa husk was characterized using Fourier Transform Infrared (FTIR), Scanning Electron Microscope (SEM) and its adsorption properties were studied by Langmuir and Freundlich kinetic isotherms.
Published: 28 December 2021
Chemical Science International Journal pp 21-32; https://doi.org/10.9734/csji/2021/v30i1230268
Aims: Chemical bonding is a fundamentalconcept which provide essential information for interpretation of chemical reactions and understanding of related concepts in chemistry. This relevance notwithstanding, the general perception of most students is that chemical bonding, as a topic is very difficult to understand. This study therefore, is an attempt to correct students’ misconceptions about chemical bonding in Rivers State, Nigeria using drama teaching strategy, with a view to addressing the issue. Study Design: Mixed method design was adopted. Place and Duration of Study: Science Education Department, Faculty of Education, Rivers State University, Port Harcourt, Nigeria. The study lasted about four months from June to October 2021. Methodology: The sample comprised 170 SS2 chemistry students. The instruments were Chemical Bonding Diagnostic Test with reliability coefficient of 0.98 and Interview Schedule. Percentages and graphs were used to answer research questions and hypotheses tested at 0.05 level of significance using Analysis of Covariance. Results: Results of the study revealed a remarkable reduction in the high extents of students’ misconceptions about chemical bonding on teaching with drama strategy while the misconceptions of students taught with lecture method persisted at a high extent; This implies that, drama teaching strategy is useful in correcting students’ misconceptions about chemical bonding while lecture teaching method is not. A significant difference in misconceptions of students taught chemical bonding with drama and those with lecture method was obtained. Also, there was significant gender related difference in students’ misconceptions about chemical bonding. Conclusion: Drama teaching strategy is effective in correcting students’ misconceptions about chemical bonding and other related concepts. Also, there is gender related difference in misconceptions based on gender.
Published: 27 December 2021
Chemical Science International Journal pp 15-20; https://doi.org/10.9734/csji/2021/v30i1230267
In this study the effects due to temperature and shear rate on viscosity for Co3O4/glycol based Nano fluids at different concentration of metal oxide and different temperatures were experimentally investigated. The structure of the prepared Co3O4/glycol nanoparticles was confirmed using XRD (X-Ray Diffraction) technique. All viscosity measurements were conducted using a capillary viscometer, the viscosity experiment were carried out at wide temperatures ranging between 20°C and 80°C to determine their applicability in such range. The viscosity data were collected using a programmable rhemoter. The result showed that the Co3O4 glycol exhibit increasing viscosity with increasing nanoparticle loading and decreasing viscosity with increasing temperature.
Published: 26 December 2021
Chemical Science International Journal pp 1-14; https://doi.org/10.9734/csji/2021/v30i1230266
The olefins product are more reactive than the corresponding alkanes, and may easily be super-oxidised into CO and CO2 in selective oxidation of alkanes. The proper balance of acid and base sites on the V-based catalyst surface plays a decisive role in limiting the complete oxidation of alkanes. Therefore, our goal was to evaluate the promoting effect of alkali metals and the support effect using boehmite as precursor for the propane oxidative dehydrogenation (ODH) reaction. Catalysts were prepared via co-impregnation of V and Na or K on a synthesized alumina support. The following characterization techniques were used: N2 adsorption-desorption, X-ray diffraction (XRD), temperature programmed reduction (TPR) and isopropanol decomposition testes to evaluate the acid-base character. The catalyst performance in the propane ODH reaction was evaluated at the O2:C3H8:He molar ratios of 5:2:4, 6:1:4, and 4:3:4. The K-doped catalysts exhibited higher propene selectivity owing to the modification of acid-base character that rendered the weaker interaction between olefinic intermediate and more basic catalyst surface. A high molar fraction of O2 of the reaction mixture minimized coke formation and a high reoxidation rate possibly increased catalytic activity and propene selectivity.
Published: 23 December 2021
Chemical Science International Journal pp 43-54; https://doi.org/10.9734/csji/2021/v30i1030265
Lead (Pb) is widely used in the informal sector and much of the exposure levels is through handling, processing, fabrications, burning and disposal of materials containing Pb. Furthermore, Pb bio-accumulate and is highly toxic to human health and is persistent in the environment. This study was therefore designed to evaluate levels of exposure to airborne Pb among workers in the informal sector. Airborne Pb was collected using air sampler in 34 production areas (sheds) and two control areas. The concentration of airborne Pb was determined using an Atomic Absorption Spectrophotometer (AAS). An empirical survey using questionnaires also assessed the knowledge about airborne Pb and occupational safety, and health strategies in place. Nearly 56.0% of the sheds had airborne Pb concentration ranging from 1.4 µg/m3 to 126.9 µg/m3. On the contrary, 44.1% of the production areas and control sites had airborne Pb levels below the detectable limit (BDL). The welding works in sheds 11 and 27, and painting activities in shed 6 and 16 had significantly (p <0.05) higher levels of airborne Pb with a mean ± standard deviation (sd) of 126.9 ± 20.1µg/m3, 117.4 ± 5.2 µg/m3 and 56.4 ± 3.1 µg/m3, and 53.6 ± 0.6 µg/m3, respectively than other operations within the sheds, and the controls areas. These levels in the welding and painting areas also exceeded the USA. Occupational Safety Health Act (OSHA) Permissive Exposure Limit (PEL) Time Weighted Average (TWA) of 50 µg/m3. The study further found that the informal sector workers had limited information about Pb exposure despite the fact that 50.0% of them had secondary education and 9.4% had primary education. About 62.0% of these workers were unaware of Pb exposure and related adverse effects. 70.6% of the workers had not taken annual medical check-ups. In addition, the workers did not have appropriate personal protective equipment (PPE) that would reduce their exposure to Pb. The study recommends comprehensive awareness and training programs on Pb exposure and occupational safety and health in the informal work environment to prevent associated health effects.