Pub Date : 2021-01-10DOI: 10.34198/EJCS.5221.261274
L. Türker
NTO and TNAZ are two important explosive materials. In the present study, 1:1 molar composite of them are investigated within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p). Certain quantum chemical, physicochemical and spectral properties of the composite have been harvested and compared with the respective values of its components. The formation of composite is exothermic and favorable. The components in the composite undergo certain type of interaction to affect properties of each other.
{"title":"A Composite of NTO and TNAZ-A DFT Treatment","authors":"L. Türker","doi":"10.34198/EJCS.5221.261274","DOIUrl":"https://doi.org/10.34198/EJCS.5221.261274","url":null,"abstract":"NTO and TNAZ are two important explosive materials. In the present study, 1:1 molar composite of them are investigated within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p). Certain quantum chemical, physicochemical and spectral properties of the composite have been harvested and compared with the respective values of its components. The formation of composite is exothermic and favorable. The components in the composite undergo certain type of interaction to affect properties of each other.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89573462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-31DOI: 10.34198/ejcs.5121.241248
N. Saba, Musa A. Dickson, O. Cyril
Under favorable growth conditions, fungi produced aflatoxins. Aflatoxin B1 (AFB1) categorized as a carcinogen is the most toxic and subject of regulation in foods and feeds in many countries. AFB1 contamination has been reported in a wide range of products including cigarette tobacco due to improper processing and storage conditions. This research aim at determining the concentration load of AFB1 mycotoxin in brands of cigarette tobacco commonly consumed in Lapai and Minna metropolis of Niger State Nigeria. Thirty-six (36) brands of cigarette tobacco were purchased in open markets in Minna and Lapai towns of Niger state, Nigeria. Residual AFB1 was extracted from the sample using standard procedures. HPLC analysis was used for the mycotoxin quantification. The result showed that all cigarette samples produces AFB1 with a concentration of 302 µg/mL and 18 µg/mL as the highest and lowest AFB1 concentration respectively for the local – Nigeria brands compared to 166 µg/mL and 8 µg/mL AFB1 concentration observed for the foreign brands. The findings from this study provide sufficient levels of contamination to pose significant health hazard for the consumer of the tobacco. Careful processing and storage is therefore advocated to eliminate or reduce the mycotoxin contamination of the cigarette brands.
{"title":"HPLC Analysis of Aflatoxin B1 Contamination of Local and Foreign Brands of Cigarette Tobacco Popularly Consumed in Niger State North-Central Nigeria","authors":"N. Saba, Musa A. Dickson, O. Cyril","doi":"10.34198/ejcs.5121.241248","DOIUrl":"https://doi.org/10.34198/ejcs.5121.241248","url":null,"abstract":"Under favorable growth conditions, fungi produced aflatoxins. Aflatoxin B1 (AFB1) categorized as a carcinogen is the most toxic and subject of regulation in foods and feeds in many countries. AFB1 contamination has been reported in a wide range of products including cigarette tobacco due to improper processing and storage conditions. This research aim at determining the concentration load of AFB1 mycotoxin in brands of cigarette tobacco commonly consumed in Lapai and Minna metropolis of Niger State Nigeria. Thirty-six (36) brands of cigarette tobacco were purchased in open markets in Minna and Lapai towns of Niger state, Nigeria. Residual AFB1 was extracted from the sample using standard procedures. HPLC analysis was used for the mycotoxin quantification. The result showed that all cigarette samples produces AFB1 with a concentration of 302 µg/mL and 18 µg/mL as the highest and lowest AFB1 concentration respectively for the local – Nigeria brands compared to 166 µg/mL and 8 µg/mL AFB1 concentration observed for the foreign brands. The findings from this study provide sufficient levels of contamination to pose significant health hazard for the consumer of the tobacco. Careful processing and storage is therefore advocated to eliminate or reduce the mycotoxin contamination of the cigarette brands.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"8 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91508517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-29DOI: 10.34198/ejcs.5121.231240
Y. Abubakar
Ziziphus spina found in the tropical regions of the world is a small tree capable of resisting heat and drought. The edible portion of the fruit is widely preserved as feed for human and animal especially in drought and famine ravaged nations of the world. The edible fruit of Z. spina were procured from a local market in Gusau, Zanfara State North-Western Nigeria in October 2019. They were prepared for proximate and mineral analyses using standard analytical methods. The results showed the percentage (%) moisture, ash, crude lipid, crude protein, crude fibre and total carbohydrate contentas3.13, 15.22, 3.11, 11.12, 6.45 and 64.10 respectively while the calorific values was reported to be 328.87kcal/100g.The elemental analyses revealed that potassium and copper were the most and least abundant element with concentrations of 256.12 and 2.37 mg/100 g dry weight respectively. The findings from this study reveal that Z.spina fruit contains important mineral elements that would possibly improve on the proper metabolic activity and therefore could improve on the health standard if properly utilized.
{"title":"Proximate and Selected Mineral Elements Analysis of Nigerian Ziziphus spina-christi (L.) Willd Edible Fruit Pulp","authors":"Y. Abubakar","doi":"10.34198/ejcs.5121.231240","DOIUrl":"https://doi.org/10.34198/ejcs.5121.231240","url":null,"abstract":"Ziziphus spina found in the tropical regions of the world is a small tree capable of resisting heat and drought. The edible portion of the fruit is widely preserved as feed for human and animal especially in drought and famine ravaged nations of the world. The edible fruit of Z. spina were procured from a local market in Gusau, Zanfara State North-Western Nigeria in October 2019. They were prepared for proximate and mineral analyses using standard analytical methods. The results showed the percentage (%) moisture, ash, crude lipid, crude protein, crude fibre and total carbohydrate contentas3.13, 15.22, 3.11, 11.12, 6.45 and 64.10 respectively while the calorific values was reported to be 328.87kcal/100g.The elemental analyses revealed that potassium and copper were the most and least abundant element with concentrations of 256.12 and 2.37 mg/100 g dry weight respectively. The findings from this study reveal that Z.spina fruit contains important mineral elements that would possibly improve on the proper metabolic activity and therefore could improve on the health standard if properly utilized.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86595846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-24DOI: 10.34198/ejcs.5121.221230
O. Charles
The research study was aimed at identifying the microorganism(s) associated with biogas production as well as comparing the biogas production potential of the fresh, dried and cow dung seeded pumpkin wastes as substrate. The samples were procured from different fruit seller locations within Sokoto metropolis and the study conducted within a period of five weeks (35 days). Standard microbiological methods were used for isolating and identifying the microbes while fabricated anaerobic bio-digesters were used to ascertain the biogas production from the substrates. Analysis revealed that the pH varied between 6.30 to 7.20 and 5.0 to 6.2 before and during/after the anaerobic digestion respectively. Anaerobic bacteria isolated were identified as Enterobacter spp and Escherichia coli. The results showed 4850, 1430 and 1770 cm3 biogas production from the fresh, dried and cow dung co-seeded substrates respectively during the retention periods with a calorific value of 4773 kcal/kg. The volume of biogas produced varied significantly (p<0.05) between the substrate treatments and the digestion intervals (days). GC-MS analysis confirmed the identity of the produced methane. This study confirmed the role of bacteria as well as the capability of the substrate to produce biogas production in an in vitro bio-digester system.
{"title":"Study of the Microbial Composition and Comparative Biogas Production from Fresh, Dried and Cow-Dung Seeded Pumpkin (Cucurbita maxima) Residue","authors":"O. Charles","doi":"10.34198/ejcs.5121.221230","DOIUrl":"https://doi.org/10.34198/ejcs.5121.221230","url":null,"abstract":"The research study was aimed at identifying the microorganism(s) associated with biogas production as well as comparing the biogas production potential of the fresh, dried and cow dung seeded pumpkin wastes as substrate. The samples were procured from different fruit seller locations within Sokoto metropolis and the study conducted within a period of five weeks (35 days). Standard microbiological methods were used for isolating and identifying the microbes while fabricated anaerobic bio-digesters were used to ascertain the biogas production from the substrates. Analysis revealed that the pH varied between 6.30 to 7.20 and 5.0 to 6.2 before and during/after the anaerobic digestion respectively. Anaerobic bacteria isolated were identified as Enterobacter spp and Escherichia coli. The results showed 4850, 1430 and 1770 cm3 biogas production from the fresh, dried and cow dung co-seeded substrates respectively during the retention periods with a calorific value of 4773 kcal/kg. The volume of biogas produced varied significantly (p<0.05) between the substrate treatments and the digestion intervals (days). GC-MS analysis confirmed the identity of the produced methane. This study confirmed the role of bacteria as well as the capability of the substrate to produce biogas production in an in vitro bio-digester system.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84984980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-24DOI: 10.34198/ejcs.5121.207219
S. Haruna, A. Musa, G. T. Ayinla
Mining activities have long been recognized as a major source of environmental contamination associated with heavy metals. In this study, ten (10) trace metals namely As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb and Zn were analysed from water (stream, river and borehole) and soil (surface and sub-soil) samples collected from around the artisanal and small scale gold mining site within the vicinity in Kuchiko-Hausa, Gurara LGA, Niger State, Nigeria using Atomic Absorption Spectroscopy. The result from the water and soil samples showed the while all the investigated trace metals were absent from all the water samples, Hg was only found with concentration of 0.006 and 0.0053 mg/mL for the stream and river water samples, the soil samples showed the presence of all the trace metals except Cd and Co with As and Cr found only in the surface soil. All detected trace metals in the samples were all lower than the WHO permissible limits. Periodic and systematic study of the investigated and other metals concentrations is therefore recommended since long-term exposure of these metals poses significant health risk for human, animals and plants.
{"title":"Trace and Heavy Metal Contamination Status of Soil and Water in Artisanal and Small Scale Gold Mining Vicinity in Kuchiko-Hausa, Gurara LGA, Niger State, Nigeria","authors":"S. Haruna, A. Musa, G. T. Ayinla","doi":"10.34198/ejcs.5121.207219","DOIUrl":"https://doi.org/10.34198/ejcs.5121.207219","url":null,"abstract":"Mining activities have long been recognized as a major source of environmental contamination associated with heavy metals. In this study, ten (10) trace metals namely As, Cd, Co, Cr, Cu, Fe, Hg, Ni, Pb and Zn were analysed from water (stream, river and borehole) and soil (surface and sub-soil) samples collected from around the artisanal and small scale gold mining site within the vicinity in Kuchiko-Hausa, Gurara LGA, Niger State, Nigeria using Atomic Absorption Spectroscopy. The result from the water and soil samples showed the while all the investigated trace metals were absent from all the water samples, Hg was only found with concentration of 0.006 and 0.0053 mg/mL for the stream and river water samples, the soil samples showed the presence of all the trace metals except Cd and Co with As and Cr found only in the surface soil. All detected trace metals in the samples were all lower than the WHO permissible limits. Periodic and systematic study of the investigated and other metals concentrations is therefore recommended since long-term exposure of these metals poses significant health risk for human, animals and plants.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81161476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-24DOI: 10.34198/ejcs.5121.191206
H. Abubakar, Y. Ndatsu, Achimugu Dickson Musa, C. Ogbiko, Hamza Usman, F. G. Mayaki, A. Mohammed
The knowledge of identifiable differences in the metabolism and macromolecular structure between infective agents and their host can be exploited in rational drug design. Ribokinase, an enzyme that plays an important role in the phosphorylation of several metabolites is one of such that can be exploited. This study was therefore aimed at structurally modelling ribokinase from Salmonella Typhi, the causative agent of typhoid fever, with several known multi-drug resistant strains. NCBI BLASTp was carried out against Protein Data Bank (PDB) to run a similarity search. Multiple sequence alignment between the query sequence and the templates was carried out using clustal omega and MEGA6.0 software. The amino acid sequence was submitted to modelling servers. The predicted models from the servers were evaluated with RAMPAGE and superimposed in the template using PyMOL. Model with highest Ramachandran plot score was further validated. BLASTp result showed low identity of (41%) with pyridoxal kinase from Trypanosoma brucei in PDB database. Conserved sequence motifs were confirmed. Template 4X8F was chosen based on its high identity, query cover and appearance in the modeling tools. Swiss model showed best Ramachandran plot score (94.9%). ERRAT analysis showed quality factor: 92.9078 and VERIFY3D server showed that 84.43% of the residues have an average score of 3D/ ID score >=0.2. Superimposition confirmed the alignment of the active site residues having aspartic acid as the catalytic residue. This study can serve as a means for rational drug design for the treatment of typhoid fever.
了解感染因子和宿主之间代谢和大分子结构的可识别差异可以用于合理的药物设计。核糖激酶是一种在几种代谢物的磷酸化中起重要作用的酶，是可以利用的酶之一。因此，本研究旨在对伤寒沙门氏菌(伤寒的病原体)的核糖激酶进行结构模拟，并对几种已知的多重耐药菌株进行模拟。利用NCBI BLASTp对蛋白质数据库(Protein Data Bank, PDB)进行相似性搜索。利用cluster omega和MEGA6.0软件对查询序列与模板进行多次序列比对。氨基酸序列提交给建模服务器。使用RAMPAGE对来自服务器的预测模型进行评估，并使用PyMOL在模板中进行叠加。进一步验证Ramachandran情节评分最高的模型。BLASTp结果显示与PDB数据库中的布鲁氏锥虫吡哆醛激酶同源性较低(41%)。保守序列基序得到确认。基于模板4X8F在建模工具中的高标识性、查询覆盖率和外观，选择模板4X8F。瑞士模型Ramachandran情节评分最高(94.9%)。ERRAT分析质量因子为92.9078,VERIFY3D服务器显示84.43%的残留物3D/ ID平均得分>=0.2。重叠证实了以天冬氨酸为催化残基的活性位点残基的排列。本研究可为合理设计治疗伤寒的药物提供依据。
{"title":"In silico Structural Modelling of Ribokinase from Salmonella Typhi","authors":"H. Abubakar, Y. Ndatsu, Achimugu Dickson Musa, C. Ogbiko, Hamza Usman, F. G. Mayaki, A. Mohammed","doi":"10.34198/ejcs.5121.191206","DOIUrl":"https://doi.org/10.34198/ejcs.5121.191206","url":null,"abstract":"The knowledge of identifiable differences in the metabolism and macromolecular structure between infective agents and their host can be exploited in rational drug design. Ribokinase, an enzyme that plays an important role in the phosphorylation of several metabolites is one of such that can be exploited. This study was therefore aimed at structurally modelling ribokinase from Salmonella Typhi, the causative agent of typhoid fever, with several known multi-drug resistant strains. NCBI BLASTp was carried out against Protein Data Bank (PDB) to run a similarity search. Multiple sequence alignment between the query sequence and the templates was carried out using clustal omega and MEGA6.0 software. The amino acid sequence was submitted to modelling servers. The predicted models from the servers were evaluated with RAMPAGE and superimposed in the template using PyMOL. Model with highest Ramachandran plot score was further validated. BLASTp result showed low identity of (41%) with pyridoxal kinase from Trypanosoma brucei in PDB database. Conserved sequence motifs were confirmed. Template 4X8F was chosen based on its high identity, query cover and appearance in the modeling tools. Swiss model showed best Ramachandran plot score (94.9%). ERRAT analysis showed quality factor: 92.9078 and VERIFY3D server showed that 84.43% of the residues have an average score of 3D/ ID score >=0.2. Superimposition confirmed the alignment of the active site residues having aspartic acid as the catalytic residue. This study can serve as a means for rational drug design for the treatment of typhoid fever.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79224519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-20DOI: 10.34198/ejcs.5121.159173
S. Popoola, J. Unyimadu, A. O. Nubi, O. Adeleye, Ismaila Ayinde Oba, Karo Oghenede Esther, Salisu, Adamu, Moromade Abibat Lere-Aliu, Taofeek Olawale Olabiyi, Akintunde, A. Adegbite, A. Hamzat, Ekundayo Oluwaseun Adeyemi, Solomon Mordi
The current study deals with the evaluation of physicochemical characteristics, nutrient status, and variation in the height of surface water from the commodore channel, and its comparison with the hydrochemical characteristics of the monitoring borehole from the NIOMR Jetty, Lagos, Nigeria. We aim to further improve our understanding of the interrelationship of climate change and hydrological cycle, and its impacts in the Lagos coastal environments. The observed ranges of physicochemical characteristics of the surface water are dissolved oxygen (DO) 3.07-6.05mg/L; pH: 7.99-8.48; temperature 26.97-30.34°C, electrical conductivity (EC) 9680-47800mS/cm; salinity (Sal) 6.51-28.05‰ and water level 1.24-1.79m. The concentration of nutrient range from nitrite 10-36mg/l, nitrate 28-44mg/l, sulphate 38-90mg/l and phosphate 2-78mg/l. The analyzed hydrochemical characteristics from all the stations are within the desired values for healthy marine ecosystems when compared with Federal Ministry of Environment (FMENV) Nigeria permissible limits which are: DO >5 mg/l, pH 6.5-9, temperature <40°C, nitrite 1mg/l, nitrate 20mg/l, phosphate 5mg/l and sulphate 500mg/l; except low DO (<4.5mg/l) in January, November and December, and elevated nitrite, nitrate and phosphate values across the season. The low DO values may be attributed to enhanced transportation of non-biodegradable organic loads that utilize the available DO for chemical oxidation and microbial decomposition. While the enriched nitrite, nitrate and phosphate concentrations suggest enhanced productivity and influx of nutrients rich flood water from the anthropogenic source. Our study showed a coincidence in the highest brackish water height of the surface water (1.24m) from the commodore channel with the highest groundwater level (1.58m) in October. The lowest height of water levels was recorded in February and March at 2.23m and 1.79m for groundwater and surface water respectively. The similarities in the height of water levels were recorded with contrasting hydrochemical variables (e.g., high Ec vs. low Ec; and high Sal vs. low Sal), which confirmed the effect of rainfall/freshwater incursion on the surface water and simultaneous occurrence of subsurface pollution arising from seawater intrusion on the groundwater samples in October. This study had shown that a long term monitoring of rise in water levels and hydrochemical variables of surface and groundwater can be used to understand climate change and early warning predictions of flooding in coastal environments.
{"title":"Seasonal Variation on the Hydrochemistry and Height of Brackish-Water from Commodore Channel, Lagos, Nigeria","authors":"S. Popoola, J. Unyimadu, A. O. Nubi, O. Adeleye, Ismaila Ayinde Oba, Karo Oghenede Esther, Salisu, Adamu, Moromade Abibat Lere-Aliu, Taofeek Olawale Olabiyi, Akintunde, A. Adegbite, A. Hamzat, Ekundayo Oluwaseun Adeyemi, Solomon Mordi","doi":"10.34198/ejcs.5121.159173","DOIUrl":"https://doi.org/10.34198/ejcs.5121.159173","url":null,"abstract":"The current study deals with the evaluation of physicochemical characteristics, nutrient status, and variation in the height of surface water from the commodore channel, and its comparison with the hydrochemical characteristics of the monitoring borehole from the NIOMR Jetty, Lagos, Nigeria. We aim to further improve our understanding of the interrelationship of climate change and hydrological cycle, and its impacts in the Lagos coastal environments. The observed ranges of physicochemical characteristics of the surface water are dissolved oxygen (DO) 3.07-6.05mg/L; pH: 7.99-8.48; temperature 26.97-30.34°C, electrical conductivity (EC) 9680-47800mS/cm; salinity (Sal) 6.51-28.05‰ and water level 1.24-1.79m. The concentration of nutrient range from nitrite 10-36mg/l, nitrate 28-44mg/l, sulphate 38-90mg/l and phosphate 2-78mg/l. The analyzed hydrochemical characteristics from all the stations are within the desired values for healthy marine ecosystems when compared with Federal Ministry of Environment (FMENV) Nigeria permissible limits which are: DO >5 mg/l, pH 6.5-9, temperature <40°C, nitrite 1mg/l, nitrate 20mg/l, phosphate 5mg/l and sulphate 500mg/l; except low DO (<4.5mg/l) in January, November and December, and elevated nitrite, nitrate and phosphate values across the season. The low DO values may be attributed to enhanced transportation of non-biodegradable organic loads that utilize the available DO for chemical oxidation and microbial decomposition. While the enriched nitrite, nitrate and phosphate concentrations suggest enhanced productivity and influx of nutrients rich flood water from the anthropogenic source. Our study showed a coincidence in the highest brackish water height of the surface water (1.24m) from the commodore channel with the highest groundwater level (1.58m) in October. The lowest height of water levels was recorded in February and March at 2.23m and 1.79m for groundwater and surface water respectively. The similarities in the height of water levels were recorded with contrasting hydrochemical variables (e.g., high Ec vs. low Ec; and high Sal vs. low Sal), which confirmed the effect of rainfall/freshwater incursion on the surface water and simultaneous occurrence of subsurface pollution arising from seawater intrusion on the groundwater samples in October. This study had shown that a long term monitoring of rise in water levels and hydrochemical variables of surface and groundwater can be used to understand climate change and early warning predictions of flooding in coastal environments.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80924580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-20DOI: 10.34198/ejcs.5121.175190
L. Türker
1,3,5-Triamino-2,4,6-trinitrobenzene, known as TATB, is an insensitive energetic material. On the other hand, certain metals like Al, Mg etc., are often involved in formulation of certain ammunition to increase the heat output of the composite. In the present study, the interaction of TATB and magnesium is considered in TATB+Mg and TATB+2Mg composites within the constraints of density functional theory at the level of B3LYP/6-311++G(d,p). The magnesium component disturbs TATB molecule mainly conformationally without causing any bond rupture. The composite formation is favorable, exothermic and they are electronically stable. As the magnesium content increases, the composites become more sensitive to impulse stimulus. Certain physicochemical, quantum chemical and spectral data are collected and discussed.
{"title":"1,3,5-Triamino-2,4,6-trinitrobenzene and Magnesium Interaction-A DFT Treatment","authors":"L. Türker","doi":"10.34198/ejcs.5121.175190","DOIUrl":"https://doi.org/10.34198/ejcs.5121.175190","url":null,"abstract":"1,3,5-Triamino-2,4,6-trinitrobenzene, known as TATB, is an insensitive energetic material. On the other hand, certain metals like Al, Mg etc., are often involved in formulation of certain ammunition to increase the heat output of the composite. In the present study, the interaction of TATB and magnesium is considered in TATB+Mg and TATB+2Mg composites within the constraints of density functional theory at the level of B3LYP/6-311++G(d,p). The magnesium component disturbs TATB molecule mainly conformationally without causing any bond rupture. The composite formation is favorable, exothermic and they are electronically stable. As the magnesium content increases, the composites become more sensitive to impulse stimulus. Certain physicochemical, quantum chemical and spectral data are collected and discussed.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77697741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Experiments have been carried out to study the effect of agitation on particle size distribution of aspirin powder and aspirin agglomerates during vacuum contact agitated drying. Morphology G3 by Malvern was used to find the size distribution of the materials under investigation before and after the drying process at 0.1, 0.5 and 0.9 µm. It was found that due to agitation, aspirin powder portrayed from negligible to significant agglomeration dependent on the diameter of the material under investigation. While attrition and agglomeration compete together during the drying process of aspirin agglomerates, with attrition dominating at 0.1 and 0.5µm and agglomeration at 0.9 µm.
在真空接触搅拌干燥过程中，研究了搅拌对阿司匹林粉末和团聚体粒径分布的影响。采用形态学G3 by Malvern法，在0.1、0.5和0.9µm处寻找干燥过程前后所研究材料的尺寸分布。它被发现，由于搅拌，阿司匹林粉末描绘从微不足道到显著的团聚取决于所调查的材料的直径。而在阿司匹林团块干燥过程中，磨损和团聚共同竞争，在0.1和0.5µm处磨损占主导地位，在0.9µm处团聚占主导地位。
{"title":"Effect of Vacuum Contact Agitated Drying on Particle Size Distribution of Aspirin Powder and Aspirin Agglomerates","authors":"Z. Adiya, B. G. Mustafa","doi":"10.34198/ejcs.5121.7785","DOIUrl":"https://doi.org/10.34198/ejcs.5121.7785","url":null,"abstract":"Experiments have been carried out to study the effect of agitation on particle size distribution of aspirin powder and aspirin agglomerates during vacuum contact agitated drying. Morphology G3 by Malvern was used to find the size distribution of the materials under investigation before and after the drying process at 0.1, 0.5 and 0.9 µm. It was found that due to agitation, aspirin powder portrayed from negligible to significant agglomeration dependent on the diameter of the material under investigation. While attrition and agglomeration compete together during the drying process of aspirin agglomerates, with attrition dominating at 0.1 and 0.5µm and agglomeration at 0.9 µm.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80382410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carmustine is a chemotherapic substance used in treatment of various cancers. In the present study, within the constraints of density functional theory (B3LYP/6-31++G(d,p)), tautomerism of carmustine has been investigated. It may undergo 1,3-type proton tautomerism, however the obtained data for vacuum conditions indicated that the equilibrium concentration of the enol type tautomer should be low. Afterwards, interactions of those tautomers with adenine, a constituent base of DNA and RNA, have been investigated. The composites (1:1) are electronically stable. Their heat of formations are exothermic and the free energy of formation values are favorable. Some of their calculated properties (structural, physicochemical and quantum chemical) are obtained and discussed.
{"title":"Interaction of Carmustine Tautomers with Adenine - DFT Study","authors":"L. Türker","doi":"10.34198/ejcs.5121.6376","DOIUrl":"https://doi.org/10.34198/ejcs.5121.6376","url":null,"abstract":"Carmustine is a chemotherapic substance used in treatment of various cancers. In the present study, within the constraints of density functional theory (B3LYP/6-31++G(d,p)), tautomerism of carmustine has been investigated. It may undergo 1,3-type proton tautomerism, however the obtained data for vacuum conditions indicated that the equilibrium concentration of the enol type tautomer should be low. Afterwards, interactions of those tautomers with adenine, a constituent base of DNA and RNA, have been investigated. The composites (1:1) are electronically stable. Their heat of formations are exothermic and the free energy of formation values are favorable. Some of their calculated properties (structural, physicochemical and quantum chemical) are obtained and discussed.","PeriodicalId":11449,"journal":{"name":"Earthline Journal of Chemical Sciences","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87215060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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