{"title":"The Optical Qualities of a Solution Made of Copper-doped Silver Sulfide Colloidal Nanoparticles","authors":"","doi":"10.7176/cper/65-04","DOIUrl":"https://doi.org/10.7176/cper/65-04","url":null,"abstract":"","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139292599","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}
{"title":"Comparative Assessment of Combustion Properties of Carbonized and Non-carbonized Briquettes from Sawdust","authors":"","doi":"10.7176/cper/64-05","DOIUrl":"https://doi.org/10.7176/cper/64-05","url":null,"abstract":"","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74606532","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}
Natural gas plays a growing role in the energy mix by displacing coal due to its relative economic and/or environmental advantages A process of natural gas liquid (NGL) recovery utilizing internally generated energy to achieve energy efficiency was designed. The process utilizes heat generated from the compressor end of the turbo-expander to provide heat energy required to maintain the appropriate operating conditions at the intermediate and bottom sections of the demethanizer column, rather than utilizing dedicated steam generators that requires additional construction, installation, operations and maintenance cost. Simultaneously, the temperature of the hot residue gas is also dropped to the required range for export, rather than utilizing dedicated process gas coolers. The various unit operations such as heat exchangers, liquid separators, Joules Thompson Valve coefficient, demethanizer column, reflux condenser, and bottom reboiler were designed, and cost evaluation performed for each unit, while models were solved using MatLab software. The quality and composition of NGL and residue gas produced are consistent with industrial process plant data. In addition, condenser and reboiler showed that the heat removed from the condenser is 3.180.5kW and 1.65m 2 area was exchanged, while the heat for the reboiler is 474.5kW at 47.25m 2 exchanged area. Also, the temperature profile of the demethanizer column is not uniform as lower temperature is required for the rectifying section (cryogenic absorption). Thus, temperature of -90 o C to – 95 o C favours the production of sales gas as the top product stream, while a temperature range of 30 o C to 36 o C at the bottom favours the recovery of NGL product as the bottom stream. The height and diameter of demethanizer column for distillation and absorption sections are 28m and 1.55m and 7.24m and 3m respectively.
{"title":"Design and Simulation of Natural Gas Liquid Recovery Process from Rich Natural Gas","authors":"Hezekiah Braye Stephen","doi":"10.7176/cper/64-04","DOIUrl":"https://doi.org/10.7176/cper/64-04","url":null,"abstract":"Natural gas plays a growing role in the energy mix by displacing coal due to its relative economic and/or environmental advantages A process of natural gas liquid (NGL) recovery utilizing internally generated energy to achieve energy efficiency was designed. The process utilizes heat generated from the compressor end of the turbo-expander to provide heat energy required to maintain the appropriate operating conditions at the intermediate and bottom sections of the demethanizer column, rather than utilizing dedicated steam generators that requires additional construction, installation, operations and maintenance cost. Simultaneously, the temperature of the hot residue gas is also dropped to the required range for export, rather than utilizing dedicated process gas coolers. The various unit operations such as heat exchangers, liquid separators, Joules Thompson Valve coefficient, demethanizer column, reflux condenser, and bottom reboiler were designed, and cost evaluation performed for each unit, while models were solved using MatLab software. The quality and composition of NGL and residue gas produced are consistent with industrial process plant data. In addition, condenser and reboiler showed that the heat removed from the condenser is 3.180.5kW and 1.65m 2 area was exchanged, while the heat for the reboiler is 474.5kW at 47.25m 2 exchanged area. Also, the temperature profile of the demethanizer column is not uniform as lower temperature is required for the rectifying section (cryogenic absorption). Thus, temperature of -90 o C to – 95 o C favours the production of sales gas as the top product stream, while a temperature range of 30 o C to 36 o C at the bottom favours the recovery of NGL product as the bottom stream. The height and diameter of demethanizer column for distillation and absorption sections are 28m and 1.55m and 7.24m and 3m respectively.","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84870553","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}
N. Khan, Aftab Ahmad Khan, S. Ullah, Imran Ullah, Shitab Khan
Zero tillage straw retained with optimum K is an important strategy to increase cotton ( Gossypium hirsutum L.) yield and K efficiency in wheat ( Triticum aestivum L.)-cotton system. A 2 years field experiment was conducted during 2018, and 2019 to study the impact of [zero tillage straw as such on soil surface (ZT SAS ) and zero tillage straw burnt (ZT SB )] and five K rates were 0, 20, 40, 60 and 80 kg ha -1 on cotton yield and K use efficiency. Results indicated that bolls/plant –1 , weight per boll, seed cotton yields, ginning out turn and K agronomic efficiency were highest with 60-80 kg K ha –1 . Interactions revealed that ZT SAS with 60-80 kg K ha –1 had higher bolls/plant, bolls weight, seed cotton yields and ginning out turn compared to ZT SB . K agronomic efficiency indices decreased with increasing K rate. ZT SAS with 20 kg K ha –1 gave greater K agronomic efficiency than other combinations. ZT SAS with 60-80 kg potassium per hectare may be a sustainable and environmentally safe strategy to enhance cotton yield and soil fertility . from combined input of ZT with straw retained and k fertilizer application at 60 kg K ha -1 . This shows that retention of crop residues has led to the increase in the K contents of soil and microbial activity which is clear indication of an improvement in soil health (Pankhurst et al. 2002; Nie et al. 2007). In the present study, we tried to optimize K management under zero tillage methods in order to improve cotton yield in wheat-cotton system.
免耕秸秆留钾是小麦-棉花体系中提高棉花产量和钾肥效率的重要策略。通过2018年和2019年为期2年的田间试验，研究了0、20、40、60和80 kg ha -1 5种施钾量对棉花产量和钾利用效率的影响。结果表明，单株铃数、单铃重、籽棉产量、出苗期和钾肥农艺效率在60 ~ 80 kg K ha -1时最高。互作结果表明，与ZT SB相比，60 ~ 80 kg K ha -1处理的ZT SAS单株铃数、铃重、籽棉产量和出苗率均较高。钾肥农艺效率指标随施钾量的增加而降低。ZT SAS配20 kg K ha -1的钾农艺效率高于其他组合。每公顷施用60-80公斤钾的ZT SAS可能是提高棉花产量和土壤肥力的可持续和环境安全的战略。秸秆留施ZT与钾肥配合施用60 kg kha -1。这表明，作物残留物的保留导致土壤钾含量和微生物活动的增加，这是土壤健康改善的明确迹象(Pankhurst等人，2002;Nie et al. 2007)。为提高小麦-棉花体系棉花产量，在免耕条件下优化钾管理。
{"title":"Zero Tillage Plus Residue Management and K Fertilization Effect on Cotton Yield and K Use Efficiency in Wheat-Cotton System","authors":"N. Khan, Aftab Ahmad Khan, S. Ullah, Imran Ullah, Shitab Khan","doi":"10.7176/cper/64-03","DOIUrl":"https://doi.org/10.7176/cper/64-03","url":null,"abstract":"Zero tillage straw retained with optimum K is an important strategy to increase cotton ( Gossypium hirsutum L.) yield and K efficiency in wheat ( Triticum aestivum L.)-cotton system. A 2 years field experiment was conducted during 2018, and 2019 to study the impact of [zero tillage straw as such on soil surface (ZT SAS ) and zero tillage straw burnt (ZT SB )] and five K rates were 0, 20, 40, 60 and 80 kg ha -1 on cotton yield and K use efficiency. Results indicated that bolls/plant –1 , weight per boll, seed cotton yields, ginning out turn and K agronomic efficiency were highest with 60-80 kg K ha –1 . Interactions revealed that ZT SAS with 60-80 kg K ha –1 had higher bolls/plant, bolls weight, seed cotton yields and ginning out turn compared to ZT SB . K agronomic efficiency indices decreased with increasing K rate. ZT SAS with 20 kg K ha –1 gave greater K agronomic efficiency than other combinations. ZT SAS with 60-80 kg potassium per hectare may be a sustainable and environmentally safe strategy to enhance cotton yield and soil fertility . from combined input of ZT with straw retained and k fertilizer application at 60 kg K ha -1 . This shows that retention of crop residues has led to the increase in the K contents of soil and microbial activity which is clear indication of an improvement in soil health (Pankhurst et al. 2002; Nie et al. 2007). In the present study, we tried to optimize K management under zero tillage methods in order to improve cotton yield in wheat-cotton system.","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81224972","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}
The aim was to the mineral content of edible and egg-shell powder Abstract In this study, the effect on the mineral content of eggs from local and exotic breed hens was investigated. For this study, random samples were collected from the Ethiopian Institute of Agricultural Research, Debrezeit Agricultural Research Center, and Fresh Corner Poultry Farming Debrezeite, Ethiopia for the exotic and local breed eggs respectively. Eggshells and edible portion of the egg were analyzed for Calcium (Ca), Potassium (K), Phosphors (P), Sodium (Na), Magnesium (Mg), Iron (Fe), Zinc (Zn), Manganese (Mn), and Copper (Cu) contents. The Phosphors and Zinc contents of the edible egg portion were higher in the local breed eggs than in exotic breed eggs. Calcium and Magnesium content of the eggshell was higher in local breed eggs while Zn content showed a marked decrease. As far as Potassium, Magnesium, Sodium Phosphors, and Copper values were concerned, these did not differ between the eggs from local and exotic breed types. The present finding provides sizeable differences in mineral content between the eggs from the local and exotic breed hens. The results afford a point of departure measurements of major and trace mineral contents of eggs and suggest quantifiable differences amid eggs from hens in different husbandry systems, and hens breed types. The physiological significance of those differences is discussed. But, future studies should elucidate differences observed by crossbreed types, diet effect, and husbandry system. Drying eggs can be a workable food systems intervention that can mend the wellbeing and eminence of diets in low-income countries like Ethiopia.
{"title":"Comparative Study on Major and Trace Mineral Content of Edible and Eggshell Powders from Ethiopian Local and Exotic Breed Chicken Eggs","authors":"E. Abrha, Zerihun Asefa","doi":"10.7176/cper/64-01","DOIUrl":"https://doi.org/10.7176/cper/64-01","url":null,"abstract":"The aim was to the mineral content of edible and egg-shell powder Abstract In this study, the effect on the mineral content of eggs from local and exotic breed hens was investigated. For this study, random samples were collected from the Ethiopian Institute of Agricultural Research, Debrezeit Agricultural Research Center, and Fresh Corner Poultry Farming Debrezeite, Ethiopia for the exotic and local breed eggs respectively. Eggshells and edible portion of the egg were analyzed for Calcium (Ca), Potassium (K), Phosphors (P), Sodium (Na), Magnesium (Mg), Iron (Fe), Zinc (Zn), Manganese (Mn), and Copper (Cu) contents. The Phosphors and Zinc contents of the edible egg portion were higher in the local breed eggs than in exotic breed eggs. Calcium and Magnesium content of the eggshell was higher in local breed eggs while Zn content showed a marked decrease. As far as Potassium, Magnesium, Sodium Phosphors, and Copper values were concerned, these did not differ between the eggs from local and exotic breed types. The present finding provides sizeable differences in mineral content between the eggs from the local and exotic breed hens. The results afford a point of departure measurements of major and trace mineral contents of eggs and suggest quantifiable differences amid eggs from hens in different husbandry systems, and hens breed types. The physiological significance of those differences is discussed. But, future studies should elucidate differences observed by crossbreed types, diet effect, and husbandry system. Drying eggs can be a workable food systems intervention that can mend the wellbeing and eminence of diets in low-income countries like Ethiopia.","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88214016","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}
Pests and diseases are prevalent on food commodities such as maize, sorghum, millet, and cassava in the field and during storage. Toxigenic fungi such as Aspergillus, Fusarium, and Penicillium create mycotoxins, which are secondary metabolites. Both people and animals are susceptible to their mutagenic, teratogenic, and carcinogenic effects. Aspergillus flavus and Aspergillus parasitic generate the most potent mycotoxins, which are found in agricultural products such as peanuts, maize grains, cereals, and animal feed. The most common incidence and stability of these mycotoxins to physical and chemical variables during food and feed processing offer substantial health risks to humans and animals. As a result, the best way to deal with this condition is to use both natural and synthetic detoxification methods. The goal of this review is to look at how natural and synthetic chemical approaches can be used to control aflatoxins contamination and how they can be reduced. Antioxidants are compounds that help prevent or reduce cell damage caused by free radicals, which are unstable molecules produced by the body in response to environmental and other stresses. Oxidative stress, which causes DNA, protein, and lipid damage at the cell level, is one of AFB1's harmful mechanisms. Antioxidants have been used as food additives to defend against oxidative deterioration since they are known to prevent fungal formation. Among the various options, antioxidants are one of the control methods of mycotoxin and which are regulated as dietary supplements and food consumption components. To reduce the effect of toxicity, the best way to prevent aflatoxin prevalence in agricultural products is to make suitable harvesting and storage conditions, but if that is not possible, it is better to eat fermented foods (yogurt or dairy drinks) or take probiotics, which are available as capsules, tablets, or powders.
{"title":"Review of Aflatoxin Reduction Potential of Antioxidants","authors":"E. Abrha, Zerihun Asefa","doi":"10.7176/cper/64-02","DOIUrl":"https://doi.org/10.7176/cper/64-02","url":null,"abstract":"Pests and diseases are prevalent on food commodities such as maize, sorghum, millet, and cassava in the field and during storage. Toxigenic fungi such as Aspergillus, Fusarium, and Penicillium create mycotoxins, which are secondary metabolites. Both people and animals are susceptible to their mutagenic, teratogenic, and carcinogenic effects. Aspergillus flavus and Aspergillus parasitic generate the most potent mycotoxins, which are found in agricultural products such as peanuts, maize grains, cereals, and animal feed. The most common incidence and stability of these mycotoxins to physical and chemical variables during food and feed processing offer substantial health risks to humans and animals. As a result, the best way to deal with this condition is to use both natural and synthetic detoxification methods. The goal of this review is to look at how natural and synthetic chemical approaches can be used to control aflatoxins contamination and how they can be reduced. Antioxidants are compounds that help prevent or reduce cell damage caused by free radicals, which are unstable molecules produced by the body in response to environmental and other stresses. Oxidative stress, which causes DNA, protein, and lipid damage at the cell level, is one of AFB1's harmful mechanisms. Antioxidants have been used as food additives to defend against oxidative deterioration since they are known to prevent fungal formation. Among the various options, antioxidants are one of the control methods of mycotoxin and which are regulated as dietary supplements and food consumption components. To reduce the effect of toxicity, the best way to prevent aflatoxin prevalence in agricultural products is to make suitable harvesting and storage conditions, but if that is not possible, it is better to eat fermented foods (yogurt or dairy drinks) or take probiotics, which are available as capsules, tablets, or powders.","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75282336","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}
Leaf spring is a component that accept dynamic loads and provide driving comfort. Leaf springs that have been used for a long time will experience a decrease in the quality that causes fracture. The test of leaf spring includes chemical composition, hardness, fractography and metallography. The results show leaf spring is medium carbon steel of 0.47% C, the average hardness value of broken leaf springs is 419.7 means does not experience significant changes, the microstructure of broken leaf springs was tempered martensitic, has corrosion attack, trans granular cracking, secondary crack and crevice corrosion, and the fracture first occurred in the upper position of the middle leaf springs, while the remaining fractures were at the edges, there was also a corrosion attack on the bottom of the leaf springs, forming rough holes. The initial fracture is marked by the presence of a beach mark. This shape is a characteristic of fatigue fracture. Keywords: chemical composition, hardness, metallography, fractography DOI: 10.7176/CPER/63-04 Publication date: October 31 st 2020
{"title":"Leaf Spring Damages Analysis on Four Wheel Vehicle","authors":"Media Nofri","doi":"10.7176/cper/63-04","DOIUrl":"https://doi.org/10.7176/cper/63-04","url":null,"abstract":"Leaf spring is a component that accept dynamic loads and provide driving comfort. Leaf springs that have been used for a long time will experience a decrease in the quality that causes fracture. The test of leaf spring includes chemical composition, hardness, fractography and metallography. The results show leaf spring is medium carbon steel of 0.47% C, the average hardness value of broken leaf springs is 419.7 means does not experience significant changes, the microstructure of broken leaf springs was tempered martensitic, has corrosion attack, trans granular cracking, secondary crack and crevice corrosion, and the fracture first occurred in the upper position of the middle leaf springs, while the remaining fractures were at the edges, there was also a corrosion attack on the bottom of the leaf springs, forming rough holes. The initial fracture is marked by the presence of a beach mark. This shape is a characteristic of fatigue fracture. Keywords: chemical composition, hardness, metallography, fractography DOI: 10.7176/CPER/63-04 Publication date: October 31 st 2020","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84184539","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}
Croton macrostachyus which is called ‘rush foil’ or ‘broadleaved croton is a multipurpose, medium sized, drought-deciduous pioneer tree. It is a tall tree found in tropical regions of Africa. The genus Croton belongs to the family Euphorbiaceae, which commonly known as the ‘spurge’ family, and it is known as ‘Bisana’ (in Amharic). Traditionally, C. macrostachyus used for treatment of malaria, rabies, gonorrhea, wound, diarrhea, hepatitis, jaundice, scabies, toothache, abdominal pain, cancer, typhoid, pneumonia and gastrointestinal disorders and as ethno-veterinary medicine. The air dried and powdered plant material (400g) was first soaked with 500mL n-hexane for 48hours and yielded 2g of n-hexane extract. Marc was soaked with 500mL of chloroform for 36hours and afforded 3.5g of chloroform extract. Finally, Marc was soaked with 500mL of methanol and yielded 18g of methanol extract. The chloroform extract of the stem bark of C. macrostachyus afforded a compound coded as EO . Its Structural determination was accomplished by means of spectroscopic techniques, namely IR, 1 H NMR, 13 C NMR and DEPT-135. The compound, EO was isolated and characterized from the stem bark of C. macrostachyus . Generally, more advanced chromatographic techniques are required to isolate more compounds from stem bark of C. macrostachyus . Also MS and 2D NMR spectroscopic techniques are needed to fully characterize the isolated compound. Keywords: C. macrostachyus; ethno-veterinary; characterization; chromatographic techniques; spectroscopic techniques. DOI: 10.7176/CPER/63-01 Publication date: October 31 st 2020
{"title":"Phytochemical Investigation and Characterization on the Stem Bark Extract of Croton macrostachyus","authors":"Teshale Ayano Begeno","doi":"10.7176/cper/63-01","DOIUrl":"https://doi.org/10.7176/cper/63-01","url":null,"abstract":"Croton macrostachyus which is called ‘rush foil’ or ‘broadleaved croton is a multipurpose, medium sized, drought-deciduous pioneer tree. It is a tall tree found in tropical regions of Africa. The genus Croton belongs to the family Euphorbiaceae, which commonly known as the ‘spurge’ family, and it is known as ‘Bisana’ (in Amharic). Traditionally, C. macrostachyus used for treatment of malaria, rabies, gonorrhea, wound, diarrhea, hepatitis, jaundice, scabies, toothache, abdominal pain, cancer, typhoid, pneumonia and gastrointestinal disorders and as ethno-veterinary medicine. The air dried and powdered plant material (400g) was first soaked with 500mL n-hexane for 48hours and yielded 2g of n-hexane extract. Marc was soaked with 500mL of chloroform for 36hours and afforded 3.5g of chloroform extract. Finally, Marc was soaked with 500mL of methanol and yielded 18g of methanol extract. The chloroform extract of the stem bark of C. macrostachyus afforded a compound coded as EO . Its Structural determination was accomplished by means of spectroscopic techniques, namely IR, 1 H NMR, 13 C NMR and DEPT-135. The compound, EO was isolated and characterized from the stem bark of C. macrostachyus . Generally, more advanced chromatographic techniques are required to isolate more compounds from stem bark of C. macrostachyus . Also MS and 2D NMR spectroscopic techniques are needed to fully characterize the isolated compound. Keywords: C. macrostachyus; ethno-veterinary; characterization; chromatographic techniques; spectroscopic techniques. DOI: 10.7176/CPER/63-01 Publication date: October 31 st 2020","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76908233","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}
Science laboratory is a very important resource input for teaching science. Learning science is enhanced and the understanding level is improved when students are engaged in science laboratory for practical experiments. Since chemistry is a branch of science, it should be also assisted with practical activities. The current study aimed to assess the status of chemistry laboratory and practical activities in secondary and preparatory schools of East Gojjam zone. A random sampling technique was employed to collect data from students and chemistry teachers of the study area. Structured and semi-structured questionnaires and observation of laboratories was used. Both teacher’s and student’s response in the study area agree on the significance of practical laboratory works to learn chemistry is very high. The result shows as Grade 9 and grade 10 students never do practical work in the lab but grade 11 and grade 12 students sometimes conduct practical work in the lab. This may be one of the reasons why only 8,688 (11.5%) students have joined the natural science field according to the 2009E.C. East Gojjam Zone Educational Bureau report. Preparatory school students also conduct only few experimental activities among the experiment listed in their own chemistry text book. As teachers give the reasons on why laboratory work is not used to teach chemistry is because of lack of chemicals and apparatuses, fear of chemicals, lack of administration support, the lab is poorly organized, no time is allotted for practical lab work, practical lab work is not considered as a teaching load for teachers and lack of laboratory training on how to use laboratory to teach chemistry in high and preparatory schools. Generally the above problem hinders practical activities in the laboratory and makes students at secondary schools of the study area lack interest to join science class. Keywords: Laboratory, secondary and preparatory school, practical activity, chemistry. DOI: 10.7176/CPER/63-02 Publication date: October 31 st 2020
{"title":"Status of Chemistry Laboratory and Practical Activities in Secondary and Preparatory Schools of East Gojjam, Ethiopia","authors":"Abebaw Shitahun Ayicheh","doi":"10.7176/cper/63-02","DOIUrl":"https://doi.org/10.7176/cper/63-02","url":null,"abstract":"Science laboratory is a very important resource input for teaching science. Learning science is enhanced and the understanding level is improved when students are engaged in science laboratory for practical experiments. Since chemistry is a branch of science, it should be also assisted with practical activities. The current study aimed to assess the status of chemistry laboratory and practical activities in secondary and preparatory schools of East Gojjam zone. A random sampling technique was employed to collect data from students and chemistry teachers of the study area. Structured and semi-structured questionnaires and observation of laboratories was used. Both teacher’s and student’s response in the study area agree on the significance of practical laboratory works to learn chemistry is very high. The result shows as Grade 9 and grade 10 students never do practical work in the lab but grade 11 and grade 12 students sometimes conduct practical work in the lab. This may be one of the reasons why only 8,688 (11.5%) students have joined the natural science field according to the 2009E.C. East Gojjam Zone Educational Bureau report. Preparatory school students also conduct only few experimental activities among the experiment listed in their own chemistry text book. As teachers give the reasons on why laboratory work is not used to teach chemistry is because of lack of chemicals and apparatuses, fear of chemicals, lack of administration support, the lab is poorly organized, no time is allotted for practical lab work, practical lab work is not considered as a teaching load for teachers and lack of laboratory training on how to use laboratory to teach chemistry in high and preparatory schools. Generally the above problem hinders practical activities in the laboratory and makes students at secondary schools of the study area lack interest to join science class. Keywords: Laboratory, secondary and preparatory school, practical activity, chemistry. DOI: 10.7176/CPER/63-02 Publication date: October 31 st 2020","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88237371","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}
In this study, polyvinyl alcohol (PVA) polymer and Cloisite 15A, a modified form of organo Montmorillonite nanoclay, are used to produce nanofibrous mats via electrospinning technique. Pure PVA nanofibrous mats from mechanically stirred polymeric solutions at 8, 10 and 12 wt % PVA percents; and nanoclay added PVA nanofibrous mat samples are produced at increased nanoclay weight/ polymer weight ratios (1/13, 1/11, 1/9 and 1/6) using several mechanically stirred nanoclay-PVA solutions at various proportions of nanoclay and PVA polymer wt % in solutions. The viscosities, surface tensions and electrical conductivities of solutions were measured. FESEM (Field Emission Scanning Electron Microscopy) analysis, fiber diameter distribution with Image J software analysis and tensile testing was applied to nanofibrous samples. Increased polymer concentration led to bead-free nanofibrous PVA mats. EDX analysis approved nanoclay is present in samples produced from nanoclay added PVA solutions. Mechanical stirring for nanoclay dispersion enabled smooth nanofibrous structures only in low (1/13) nanoclay weight/ polymer weight ratios and showed very little tensile increase from 1 wt % clay loading to 2 wt % addition. A direct increase in tensile strength wasn’t achieved with nanoclay content increase in PVA nanofibrous mats; this might be due to the effect of poor nanoclay distribution adversely affecting tensile results. Morphological analysis proved that nanofibrous structures were far away from smooth fiber structures as they transformed from smooth nanofibers into non-uniform fibrous structures at increased nanoclay weight/ polymer weight ratios in nanoclay added PVA samples. Keywords: nanofibrous mat, electrospinning, polyvinyl alcohol (PVA), nanoclay, mechanical dispersion DOI : 10.7176/CPER/62-08 Publication date: May 30 th 2020
{"title":"Study on the Morphology and Fiber Properties of Nanoclay Added Polyvinyl Alcohol (PVA) Nanofibrous Mats: Effect of Mechanical Dispersion","authors":"Reyhan Keskin, M. Koç","doi":"10.7176/cper/62-08","DOIUrl":"https://doi.org/10.7176/cper/62-08","url":null,"abstract":"In this study, polyvinyl alcohol (PVA) polymer and Cloisite 15A, a modified form of organo Montmorillonite nanoclay, are used to produce nanofibrous mats via electrospinning technique. Pure PVA nanofibrous mats from mechanically stirred polymeric solutions at 8, 10 and 12 wt % PVA percents; and nanoclay added PVA nanofibrous mat samples are produced at increased nanoclay weight/ polymer weight ratios (1/13, 1/11, 1/9 and 1/6) using several mechanically stirred nanoclay-PVA solutions at various proportions of nanoclay and PVA polymer wt % in solutions. The viscosities, surface tensions and electrical conductivities of solutions were measured. FESEM (Field Emission Scanning Electron Microscopy) analysis, fiber diameter distribution with Image J software analysis and tensile testing was applied to nanofibrous samples. Increased polymer concentration led to bead-free nanofibrous PVA mats. EDX analysis approved nanoclay is present in samples produced from nanoclay added PVA solutions. Mechanical stirring for nanoclay dispersion enabled smooth nanofibrous structures only in low (1/13) nanoclay weight/ polymer weight ratios and showed very little tensile increase from 1 wt % clay loading to 2 wt % addition. A direct increase in tensile strength wasn’t achieved with nanoclay content increase in PVA nanofibrous mats; this might be due to the effect of poor nanoclay distribution adversely affecting tensile results. Morphological analysis proved that nanofibrous structures were far away from smooth fiber structures as they transformed from smooth nanofibers into non-uniform fibrous structures at increased nanoclay weight/ polymer weight ratios in nanoclay added PVA samples. Keywords: nanofibrous mat, electrospinning, polyvinyl alcohol (PVA), nanoclay, mechanical dispersion DOI : 10.7176/CPER/62-08 Publication date: May 30 th 2020","PeriodicalId":9769,"journal":{"name":"Chemical and Process Engineering Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91239952","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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