فهرست مطالب

Chemical Review and Letters - Volume:5 Issue: 3, Summer 2022

Chemical Review and Letters
Volume:5 Issue: 3, Summer 2022

  • تاریخ انتشار: 1401/02/11
  • تعداد عناوین: 7
  • Khushnudbek Eshchanov *, Mukhabbat Baltaeva Pages 161-168
    We studied the sorption of silver, gold, and copper ions into powdered hydrolyzed fibroin derived from silk fibroin fibers. Metal ions sorbed into hydrolyzed fibroin have been found to interact with active functional groups over time. It was hypothesized that the silver and gold ions sorbed into hydrolyzed fibroin would form nanoparticles as a result of the reduction reaction, while the copper ions would form a coordination bond. Charmm22 force field calculations were performed on this basis. The IR spectral results obtained by calculations were compared with the IR spectral results obtained in practice, and it was proved that silver and gold nanoparticles were formed and that copper ions formed coordination bonds with fibroin
    Keywords: Charmm22 force field, Hydrolyzed fibroin (“ HF” ), Nanoparticles, Coordination bonds, IR spectrum
  • Hossein Moghadam, Aghdas Banaei * Pages 169-177
    Renewable energy is one of the most important sources of energy supply in the world. Biomass power plants produce biogas under anaerobic conditions by burying organic waste. Biogas is being produced in the Mashhad Recycling Industrial Complex. This fuel is for consumers in the biogas plant to generate electricity. In this study, we performed the removal of hydrogen sulfide using water-scrubbing techniques in the form of gravity and stairs from biogas. The results show that the removal value of hydrogen sulfide varied between 34 to 87 and the removal efficiency of hydrogen sulfide varied between 34 to 97%. In addition, the loading rate of hydrogen sulfide varied between 8.1 to 40.8 g/m3.h. Moreover, the elimination capacity of hydrogen sulfide varied between 7.3 to 20.9 g/m3. h. This investigation is a novelty for design and construction in water Scrubbing. Water scrubbing systems compared to similar examples have distinguishing features in the vertical and stepped arrangement and suction to separate the remaining gases by a vacuum pump. The most important feature is the gravitational force-displacement of the water pump to flow water. Therefore, fewer water pumps are used. In this case, energy consumption is reduced
    Keywords: Biogas upgrading, Water Scrubbing, Hydrogen Sulfide
  • Eric-Simon ZRAN *, Augustin Yobouet, Lebe, Prisca Kouakou, Albert Trokourey, Benjamin Yao Pages 178-186
    This study falls not only into the theme of water depollution but also and above all into the recovery of waste (logic of the 3 R: Reduce, Reuse and Recycle). There was talk of recovering corncobs, which are considered as “agricultural waste” in developing countries such as Côte d’Ivoire. They were used as activated carbon to adsorb Black Remazol in a synthetic aqueous solution. This activated carbon obtained has a specific surface of 673.33 m²/g, a mass loss of 61.44 %, an iodine value of 168.31 mg.g-1 and a zero charge potential of 2.05. The design of experiments methodology was used on the one hand to detect the influential factors and on the other hand to optimize the elimination of this dye. Thus, in a first approach six factors (pH of the solution, mass of activated carbon, temperature, and concentration of the solution, stirring time and stirring speed) were used when using the Hadamard matrix. This showed that only three parameters, the mass of adsorbent, the concentration of the solution and the stirring time actually have an influence on the response. The results of the full two-level factorial design showed that the maximum removal rate of Black Remazol is 96.67 % under the conditions of stirring a solution with a concentration of 10 mg/L of this dye with a mass of adsorbent of 0.3 g for 20 minutes.
    Keywords: Removal rate, Adsorption, Design of experiments, Agricultural waste, Remazol black
  • Habib Ashassi-Sorkhabi *, Amir Kazempour, Jafar Mostafaei, Elnaz Asghari Pages 187-192
    The nickel-phosphorus (Ni-P) and nickel-phosphorus-nanodiamond (Ni-P-ND) coatings were deposited on mild steel via electroless plating without ultrasound and under ultrasonic agitation with different frequencies of 25, 50, 75, 100, and 150 kHz. The as-prepared coatings were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The corrosion performance of the fabricated layers was evaluated in 3.5 wt% NaCl solution by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Results of the corrosion tests demonstrated that deposition under ultrasonic power provided coatings with higher stability in the corrosive environment. The corrosion rate decreased with increasing ultrasound frequency from 25 to 75 kHz but increased with further increase in frequency. This introduced 75 kHz as the optimum ultrasound frequency for electroless plating of Ni-P. It was also observed that the corrosion resistance of the proposed coating was improved through the incorporation of 40 ppm nanodiamond into the Ni-P matrix.
    Keywords: Electroless Ni-P coating, Nanodiamond, Corrosion protection, Ultrasound wave frequency
  • Udicaël Dandjlessa *, Bénoît Ezin, Fidèle M. Assogba, Norliette Zossou, Bienvenu Glinma, Eléonore Yayi Ladekan, Joachim D. Gbenou, Aliou Saïdoud, Adam Ahanchede Pages 193-199
    Chromolaena odorata (L.) King and Robinson (Asteraceae) is a tropical shrub with interesting chemical potential widely used in agriculture and medical science and which can be affected by several geographic and climatic conditions. Therefore, we investigated the phytochemical composition of this plant across climatic zones in Benin. The plant material collected from different locations was phytochemically screened by staining and precipitation tests. The total phenolic, flavonoid and tannin contents were determined using, the colorimetric method of Folin-Ciocalteu, the method of aluminum chloride and the method of vanillin, respectively, then the obtained data were subjected to analysis of variance. The phytochemical analysis revealed the presence of the main chemical groups such as alkaloids, free anthracene, coumarins, flavonoids, mucilage, tannins, reducing compounds, saponins, quinone derivatives, steroids. There was a significant difference (P < 0.05) in the phytochemical contents across geographical sites. In comparing the levels of phytochemicals among geographical locations, the raw material collected from the north climatic zone contained the highest phenolic and flavonoid contents, 147.59 ± 3.04 mg/g and 17.17 ±0.31 mg/g, respectively, compared to others. Overall, the study highlighted the potential of C. odorata as source of natural products. There was no difference in the phytochemical markers whereas the phytochemical contents vary across climatic zones. These results can be of use in the development of biopesticides from the raw material of C. odorata.
    Keywords: Siaw weed, plant extract, Climate, allelochemicals, polyphenols
  • James Yakubu *, Olufunke Sodipo, Saleh Umarfarouk Pages 200-206
    The objective of this study was to extract the seed and plant of Momordica charantia Linn. with methanol using soxhlet apparatus, phytochemically screen the methanol extracts using standard procedures, determine the acute toxicity of the methanol extracts of seeds and plant in Wistar strain rats by Lorke’s method and evaluate the abortifacient activity on adult nonpregnant albino rat in-vitro. The phytochemical screening of both the methanol seed and plant extracts revealed the presence of carbohydrates, terpenoids, cardiac glycosides, cardenolides and saponins for seed, while carbohydrates, terpenoids, cardiac glycosides, cardenolides, saponins and flavonoids were present in the plant extract. The intraperitoneal LD50 of seed and plant extracts were calculated to be 288 mg/kg and 714 mg/kg respectively. The abortifacient activity of Momordica charantia of both plant and seeds were investigated in induced contraction on the uterus in an organ bath setup. Oxytocin was used as a standard. The seed and plant extracts in a dose dependent manner induced contraction, the amplitude of contraction and percentage increase were independently significant (p<0.05). The result showed the synergistic activity between oxytocin and the plant extract. It may be concluded that the methanol seed and plant extracts of M. charantia induced uterine contraction, thus having abortifacient activity and this justifies this claim in traditional medicine.
    Keywords: Momordica charantia, phytochemicals, Abortifacient, Acute toxicity
  • Milad Sheydaei *, Shabnam Shahbazi-Ganjgah, Ebrahim Alinia-Ahandani, Melika Sheidaie, Milad Edraki Pages 207-216

    The expansion of industry, climate change, deforestation, and pollution of oceans, and exponential increase in the multidrug-resistant bacteria, humans are more to danger than ever before. In recent years, humans have been affected more than ever by bacterial and fungal infections and even mosquito-related diseases such as lymphatic filariasis, malaria, and cellulitis. For example, Candida albicans and Aspergillus fumigatus can cause invasive fungal infections in any organ of humans, and their resistance to antibiotics is increasing. For a long period of time, plant components have been used for curing the various ailments. Herbs were the basis of medicine in the past and also are extensively used in some countries such as China and India. The study of antimicrobial effects of plants is increasing continuously, which is due to the presence of diverse levels of their bioactive compounds. Humans are so interested in using natural antibacterial compounds like plant extracts and spices because they have their own characteristic flavor. Plants are useful for supporting human health and some parts of the plant (flowers, leaves, stems, and roots) have medicinal activities such as analgesics, antispasmodics, antimicrobials. With recent advances, in addition to plants, polymers and nanoparticles have come to the help of medical cures. Polymers and nanoparticles due to their unique properties, can be used in a variety of fields such as prosthesis, antibacterial and antifungal surfaces, drug carrier, gene delivery, cancer diagnosis, colorimetric detection of cancer cells, and cancer imaging. In this study, researches on plants, polymers, and nanoparticles antibacterial are reviewed.

    Keywords: Bacterial infections, bioactive compounds, herbs, Resistant bacteria