Asian Journal of Physical and Chemical Sciences
EISSN : 2456-7779
Published by: Sciencedomain International (10.9734)
Total articles ≅ 162
Latest articles in this journal
Published: 8 October 2021
Asian Journal of Physical and Chemical Sciences pp 17-28; https://doi.org/10.9734/ajopacs/2021/v9i330138
Bioremediation is an efficient and environmentally friendly method for the degradation of petroleum hydrocarbons in contaminated soils. This study investigated the effects of biosurfactant alkyl polyglycosides (APG) on enhanced biodegradation of petroleum hydrocarbon contaminated soils. Three soil samples were contaminated with two different grades of crude oil (medium and Light). Alkyl polyglucoside was synthesised and subjected to FTIR for comfirmation of the product before it was applied in the remediation of contaminated soil. The alkyl polyglucoside is used as a treatment regime in the remediation of the hydrocarbon contamination in the three soil samples. Results of total petroleum hydrocarbons (TPH) before remediation with bio-surfactant showed that samples contaminated with medium crude for Eneka, Ozuoba and Rukpokwu were 15744.00 mg/kg, 11359.00 mg/kg and 11470.00 mg/kg respectively and after remediation reduced to 4276.00 mg/kg, 4265.00 mg/kg, and 3205.00 mg/kg, showing a reduction percentage of 72.84%, 62.44% and 72.05% respectively. Soil samples contaminated with light crude showed result of TPH of 11339.00 mg/kg, 10662 mg/kg and 10226 mg/kg and after remediation reduced to 2981 mg/kg, 3879 mg/kg, and 4245 mg/kg respectively showing a reduction percentage of 73.71%, 63.62 % and 58.49% respectively. The enhanced efficiency of the bio-surfactant at degrading total petroleum hydrocarbons was achieved as a result of the increased solubility thus improving the bioavailability of the hydrocarbons due to the action of the alkyl polyglucoside.
Published: 8 October 2021
Asian Journal of Physical and Chemical Sciences pp 29-45; https://doi.org/10.9734/ajopacs/2021/v9i330139
Cellulose extracted from Eichhornia crassipe (Water hyacinth) and Pennisetum purpureum (elephant grass) yielded 21.88% and 31.39% respectively. Cellulose extracted was used to synthesize carboxymethyl cellulose (CMC) under heterogeneous condition with ethanol as the supporting medium. Effect of concentration of sodium hydroxide (NaOH) on the modification of cellulose to yield CMC was investigated. It was observed that percentage CMC yield increased with increase in NaOH concentration. Comparative studies of the two biomass samples through physico-chemical analyses in terms of degree of substitution (DS), water absorption capacity, water loss, pH, conductivity and analytical characterization using SEM-EDX, FT-IR and EDXRF spectroscopy of the extracted cellulose and synthesized CMC were done. The DS of CMC obtained by alkalization reaction of cellulose from E. crassipe and P. purpureum with monochloroacetic acid was in the range of 0.54-0.75 which showed that it is highly soluble. Fourier Transform-Infrared (FT-IR) spectrophotometer showed changes of functional group from cellulose to CMC. The absorption at 3283 cm-1 and 3320 cm-1 as observed in E. crassipe and P. purpureum spectra showed OH vibration of polymeric compounds. The presence of bands at 1592 cm-1 and 1417 cm-1 in E. crassipe spectrum and bands at 1566 cm-1 and 1410 cm-1 observed in P. purpureum spectrum showed the presence of –COO group as a result of carboxymethylation reaction on cellulose during modification process. EDXRF was applied for quality control and product development due to the unavailability of the elemental composition of elephant grass and water hyacinth in the literature. The morphology and elemental compositions on the surface of the biomass were analyzed by SEM-EDX and among the chemical elements detected were C, O, Na, Mg, Al, S, Cl, K, Ca, Fe Si and Zr which confirms the elements identified with EDXRF spectroscopy. XRF spectra show high peaks at Fe, K and Sn for untreated P. purpureum samples and high peaks at Ca, Fe and Sr for untreated E. crassipe fiber. Both samples are rich in Iron (Fe). Samples were free from some toxic elements such as Pb, As, Hg, V and Ni which makes them safe for use as novel raw materials for industrial applications. Also very low concentration of Sulphur in the samples, make them safe to be considered as additives in drilling mud formulation.
Published: 2 October 2021
Asian Journal of Physical and Chemical Sciences pp 8-16; https://doi.org/10.9734/ajopacs/2021/v9i330137
In the Sahelian zone, air conditioning in house by air-soil heat exchangers is an alternative in the context of insufficient of electrical energy. In this work, we carried out a numerical and experimental study of thermal efficiency of an air-soil heat exchanger. This study provided an estimation of thermal efficiency of an experimental air-soil heat exchanger during June, July and August 2016. Numerical results provided a better understanding of the influence of parameters such as tube length, air velocity and soil temperature on the thermal efficiency of this system.
Published: 27 September 2021
Asian Journal of Physical and Chemical Sciences pp 1-7; https://doi.org/10.9734/ajopacs/2021/v9i330136
Copolymerization of ethylene with butadiene was carried out in the presence of nickel diethyldithiocarbamate and various modifiers. Triphenylphosphines were selected as modifiers. Solutions of nickel diethyldithiocarbamates and said modifiers in aromatic solvents of various concentrations have been prepared. Their physicochemical parameters, particle sizes in solutions, as well as mutual solubility were determined. It was demonstrated that these complexes are readily soluble in aromatic solvents, and the particle size in solution is in the nanometer range. These complexes were tested in the processes of copolymerization of ethylene with butadiene in combination with various cocatalysts - (tri-, diethylaluminum chloride). The products synthesized in their presence were analyzed by various physicochemical methods and their structure was confirmed. It has been shown that oligomeric and copolymer products with the required structure can be in fact synthesized in the presence of these catalytic systems. The activity and selectivity of catalytic systems have been comparatively tested in liquid phase (co) polymerization processes. The composition and conditions have been found to have a significant effect on the activity and structure of the resulting products.
Published: 10 July 2021
Asian Journal of Physical and Chemical Sciences pp 44-54; https://doi.org/10.9734/ajopacs/2021/v9i230135
Human are exposed to Background Ionizing radiation (BIR) due to the consumption of crops from fertilized farms within the study area.an in-situ measurement of BIR exposure rate in six fertilized farms and the unfertilized farm aws carried out using a well calibrated portable nuclear radiation detector (Digilert 200). and Geographical positioning system (GPS) for measuring the geographical location. The BIR of the selected local government area varies from 0.012 mR/hr to 0.022 mR / hr and the higher BIR value recorded in Khana, Obio / Akpor, Ahuoda east and Emuoha Local Government area (0.015 mR/hr, 0.015 mR / hr , 0.014 mR/hr , 0.014 mR / hr . While the mean value of Eleme and Gokana were within the permissible limit of 0.013 mR/hr and the BIR of the unfertilized farm was lower than the standard value of 0.013 mR/hr.the mean of absorbed dose varies from 1131 nGy / hr to 122.1nGy/hr which was higher than the recommended safe limit of 84.0 nGy / hr UNSCEAR 2008.The mean of ELCR varies from 0.63 to 0.72x10-3 which is higher than the world average value. The AEDE varies from 0.14 to 0.33 mSv / yr which are below the recommended permissible limit of 1.0 mSv / yr for general public. The effective dose to different body organs are below the recommended limit of 1.0 mSv / yr. The study shows that fertilized farms are contaminated due consistence application of fertilizers during cultivation, but the contamination does not have any direction health effect on individual who consumed crops from fertilized farms but there is the potential for long term health hazards in future such as Cancer due to consistence consumption of crops from fertilized farms.
Published: 4 June 2021
Asian Journal of Physical and Chemical Sciences pp 36-43; https://doi.org/10.9734/ajopacs/2021/v9i230134
This article is devoted to the study of the mechanical and water properties of concrete of Typha australis. The concrete is achieved by the mixture cattail aggregates with cement, sand and water. Mechanical study showed that the density and the mechanical compressive strength decreases with the dosage of typha aggregates, and increases with the dosage of cement. However, the values obtained do not allow using this concrete in supporting structures. However, the value obtained is 0.16 MPa for the first series (S1), and 0.26 MPa for the second series (S2), for a high dosage of typha of 3.5% is sufficient for a wall of three meters high can support its own load. With a constant intrinsic porosity, these aggregates are compressible and porous. This physical condition makes the vegetable particles of typha very lightweight and sensitive to water. The lightweight concrete became sensitive to water. Increasing the dosage of typha aggregates increase the water absorption of concrete. More than 50% of the water content is absorbed during thirty minutes of immersion. It is therefore strongly recommended to waterproof the wall with typha australis.
Published: 2 June 2021
Asian Journal of Physical and Chemical Sciences pp 25-35; https://doi.org/10.9734/ajopacs/2021/v9i230133
Evaluation of indoor radon level and its health risk parameters has been carried out in three communities Azuabie, Trans-Amadi and Nkpogu towns in Port Harcourt, Rivers State, Nigeria. A pocket sized Corentium Arthings digital radon detector meter was used to record the indoor radon concentration levels. The geographical coordinates were recorded using a hand-held geographical positioning system (GPS) for the various sample points. A total of 30 sample points were evaluated, with 10 sample points for each town respectively. The results of the concentration levels showed that for Azuabie (AZ) town, the concentration level varied from 6.660 Bqm-3 to 13.690 Bqm-3 with an average of 10.65±0.95Bqm-3. Nkpogu (NK) town the results of the indoor concentration level ranged from 9.250 Bqm-3 to 18.870 Bqm-3 with an average of 13.32±1.02 Bqm-3, Nkpogu (NK) town, the indoor concentration level ranged from 7.030 Bqm-3 to 20.350 Bqm-3 with an average of 12.25±1.34Bqm-3. The annual absorbed dose for Azuabie, Trans-Amadi and Nkpogu varied as follows, 1.680 mSvy-1 – 3.921 mSvy-1, 2.334 mSvy-1 – 47610 mSvy-1 and 1.774 mSvy-2 – 5.134 mSvy-1 respectively. The annual effect dose rate for the three towns ranged from 0.403 mSvy-1 – 0.941mSvy-1, 0.560 mSvy-1 - 1.143 mSvy-1 and 0.426 mSvy-1 – 1.143mSvy-1. The excess life time cancer risk varied from 1.4117 – 3.294, 1.9607 – 3.999 and 1.4901 – 3.999 respectively. The results of the indoor concentration levels annual and the absorbed dose and the annual effective dose rate are all below the ICRP safe limit. However, the results of the excess life time cancer risk are all higher than the ICRP safe standard limit of 0.029×10-3.
Published: 29 April 2021
Asian Journal of Physical and Chemical Sciences pp 8-24; https://doi.org/10.9734/ajopacs/2021/v9i230132
The petroleum industry includes the global processes of exploration, extraction, refining, transportation and marketing of natural gas, crude oil and refined petroleum products. The oil industry demands more sophisticated methods for the exploitation of petroleum. As a result, the use of oil field chemicals is becoming increasingly important and has received much attention in recent years due to the vast role they play in the recovery of hydrocarbons which has enormous commercial benefits. The three main sectors of the petroleum industry are Upstream, Midstream and Downstream. The Upstream deals with exploration and the subsequent production (drilling of exploration wells to recover oil and gas). In the Midstream sector, petroleum produced is transported through pipelines as natural gas, crude oil, and natural gas liquids. Downstream sector is basically involved in the processing of the raw materials obtained from the Upstream sector. The operations comprises of refining of crude oil, processing and purifying of natural gas. Oil field chemicals offers exceptional applications in these sectors with wide range of applications in operations such as improved oil recovery, drilling optimization, corrosion protection, mud loss prevention, drilling fluid stabilization in high pressure and high temperature environment, and many others. Application of a wide range of oilfield chemicals is therefore essential to rectify issues and concerns which may arise from oil and gas operational activities. This review intends to highlight some of the oil field chemicals and their positive applications in the oil and gas Industries.
Published: 7 April 2021
Asian Journal of Physical and Chemical Sciences pp 1-7; https://doi.org/10.9734/ajopacs/2021/v9i230131
Based on the Gravito-Electro-Magnetic (GEM) equations as another form (for low fields) of Einstein's Equations of General Relativity Theory (GRT) an equation is derived for the total energy density in the universe, including the gravitational fields, the contribution thereof is always negative and so it seems to represents the Dark Energy (DE). When calculating the total energy of the universe from this equation, the result is near to zero because of negative contributions from gravitational fields, depending a little on the available parameters of the universe as e.g. it's baryonic mass. Thus the assumption is given a high amount of probability, that the total energy (mass) in the universe is really zero and very likely is always zero. This would mean, that the universe developed from empty space-time or from nothing (may be by quantum fluctuations). Looking on the development it could be that the average energy density is zero for each sufficient large part of the universe at any time, except for very local deviations (e.g. galaxies, black holes etc.). As a consequence the expansion of the universe is probably not retarded by gravity (thus the Friedmann equation and others do not apply). The expansion of the universe can be considered as driven by the pressure of a gas-like medium with positive masses as by intergalactic gas, dust, stars and galaxies. Conclusions are drawn as to the interpretation of the formation of voids in the universe, flat space etc.
Published: 22 March 2021
Asian Journal of Physical and Chemical Sciences pp 40-50; https://doi.org/10.9734/ajopacs/2021/v9i130130
Aim: The amount of waste tire generated constantly in the modern society is on a rapid increase due to the world’s urbanization, industrialization and population increase. This research was conducted to recover useful products from waste tyre and harness the possibility of using these products as a petrochemical feedstock alternative. Study Design: Conventional pyrolysis was used to produce bio char, bio-oil and bio-gas Place and Duration of Study: The research was carried out in the department of Pure and Industrial Chemistry and Mechanical Engineering Nnamdi Azikiwe University between January 2020 and march 2020 Methodology: Waste tyre was pyrolyzed using a conventional pyrolysis over three different temperature 400,550 and 750oC. The yield of the oil and char was determined by weight measurement, while that of gas was determined by mass balancing. The oil produced was characterized using GC/MS (gas chromatography/mass spectrometry) Results: The percentage yield of char, oil and gas at 400oC, 550oC and 750oC respectively are 62, 24, 14; 48, 36.2, 15.8 and 42, 40, 18. The statistical analysis of yield gave a p-value of 0.785211 this showed that there is no significant change across the three samples statistically. The GC/MS analyses of the oil showed that the oil contains more than 35 compounds of which 6 accounted for more than 50% of the oil, these six include d-limonene with 12.83%, 1-2- benzene dicarboxylic acid with 10.48%, benzene, 1-ethyl-3methyl with 8.89%, benzene 1-methyl-3-(1-methylethyl) with 8.6%, benzene 1-ethenyl-4-methyl with 6.13% and hexadecenoic acid at 5.27%,while another six accounted for less than 5% of the oil, they includes (1-methylenebut-2-enyl)benzene with 0.89%, 1-methylbut-1,3-dienyl)benzene with 0.71%, naphthalene-2,7-dimethyl with 0.71%, quinoline with 0.96%, Spiro[4,5]dec-7-ene,1,8-dimethyl-4-(1-methylethenyl) with 0.74%, phenol 4-(1,1,3,3-tetramethylbutyl). Conclusion: The composition of tire derived oil are very important petrochemicals derivatives which can be separated or can be used as feedstocks for petrochemical industries.