Pub Date : 2023-03-27DOI: 10.3329/bjsir.v58i1.64236
M. Rahman, Md. Mizanur Rahman, K. Nemoto, A. Sarwar
Along with the apparel or clothing industry, diversified uses of natural lignocellulosic fibre are getting popularity in many fields e.g., composites, automotive, marines, aerospace, electronics, civil construction, nanotechnology, biomedical, etc. The property and uses of textiles are determined by their constituent fibre properties. The proximate composition and thermogravimetric analysis (TGA) data of a total of 9 local hemp and flax genotypes (3 and 6, respectively) were carried out to understand their suitability in different applications. A wide variation was observed in the ash content of hemp and flax fibres varied from 1.7 to 17.7%, crude protein 3.27 to 9.02%, crude fibre 26.51 to 55.32%, ether extract 2.6 to 20.9% and energy value 284.44 to 383.96 kcal 100–1 g. In TGA analysis, all the fibres showed a similar trend. The flax genotypes contain lower ash and ether extract and higher DM, crude carbohydrate and crude fibre than hemp genotypes. Therefore, flax could be used in the lightweight composite, textile, pulp and cellulose-based industries. The hemp fibre had higher ash which was reflected by a higher residue at 500oC in TGA analysis. To understand the viability of these flax fibres, further investigations are needed. Bangladesh J. Sci. Ind. Res. 58(1), 65-70, 2023
{"title":"Proximate composition and thermal properties of hemp and flax fibres","authors":"M. Rahman, Md. Mizanur Rahman, K. Nemoto, A. Sarwar","doi":"10.3329/bjsir.v58i1.64236","DOIUrl":"https://doi.org/10.3329/bjsir.v58i1.64236","url":null,"abstract":"Along with the apparel or clothing industry, diversified uses of natural lignocellulosic fibre are getting popularity in many fields e.g., composites, automotive, marines, aerospace, electronics, civil construction, nanotechnology, biomedical, etc. The property and uses of textiles are determined by their constituent fibre properties. The proximate composition and thermogravimetric analysis (TGA) data of a total of 9 local hemp and flax genotypes (3 and 6, respectively) were carried out to understand their suitability in different applications. A wide variation was observed in the ash content of hemp and flax fibres varied from 1.7 to 17.7%, crude protein 3.27 to 9.02%, crude fibre 26.51 to 55.32%, ether extract 2.6 to 20.9% and energy value 284.44 to 383.96 kcal 100–1 g. In TGA analysis, all the fibres showed a similar trend. The flax genotypes contain lower ash and ether extract and higher DM, crude carbohydrate and crude fibre than hemp genotypes. Therefore, flax could be used in the lightweight composite, textile, pulp and cellulose-based industries. The hemp fibre had higher ash which was reflected by a higher residue at 500oC in TGA analysis. To understand the viability of these flax fibres, further investigations are needed.\u0000Bangladesh J. Sci. Ind. Res. 58(1), 65-70, 2023","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47613274","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 : 2023-03-27DOI: 10.3329/bjsir.v58i1.61901
H. Abroshan, S. Rezaei, H. Golchoobian, F. Foladi, Ehsan Rumizade, A. Mirshams
Sugar extraction from sugarcane/sugar-beet is an energy-intensive process, both thermal and electrical energies. However, there are numerous opportunities for energy efficiency improvements. A number of tests were conducted in an old sugarcane factory, including the boiler, electricity generation, process, and mill section, to better understand these opportunities. During four years, specific energy consumption was 16-28 GJ/ton of raw sugar. Measurements and calculations revealed that some equipment, e.g. shredder's steam turbine and some gearboxes, require extensive repairs. The second set of areas for improvement relates to proper operation, such as determining the boiler excess air (which results in an average 0.6% efficiency reduction) and factory planning (near 200 MWh per year). The third type of improvement is to modify or integrate new elements into the existing plant, like water storage tank insulation (3.8 MW) and switching from load-unload operation to drive control for instrumentation compressors (43 MWh). Bangladesh J. Sci. Ind. Res. 58(1), 09-18, 2023
{"title":"Energy audit of a sugarcane plant to find out the main energy saving opportunities","authors":"H. Abroshan, S. Rezaei, H. Golchoobian, F. Foladi, Ehsan Rumizade, A. Mirshams","doi":"10.3329/bjsir.v58i1.61901","DOIUrl":"https://doi.org/10.3329/bjsir.v58i1.61901","url":null,"abstract":"Sugar extraction from sugarcane/sugar-beet is an energy-intensive process, both thermal and electrical energies. However, there are numerous opportunities for energy efficiency improvements. A number of tests were conducted in an old sugarcane factory, including the boiler, electricity generation, process, and mill section, to better understand these opportunities. During four years, specific energy consumption was 16-28 GJ/ton of raw sugar. Measurements and calculations revealed that some equipment, e.g. shredder's steam turbine and some gearboxes, require extensive repairs. The second set of areas for improvement relates to proper operation, such as determining the boiler excess air (which results in an average 0.6% efficiency reduction) and factory planning (near 200 MWh per year). The third type of improvement is to modify or integrate new elements into the existing plant, like water storage tank insulation (3.8 MW) and switching from load-unload operation to drive control for instrumentation compressors (43 MWh).\u0000Bangladesh J. Sci. Ind. Res. 58(1), 09-18, 2023","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47211919","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 : 2023-03-27DOI: 10.3329/bjsir.v58i1.65110
F. Abderrahmane, S. Addou, I. Labadie, O. Kheroua
Aloe vera (A v) is a medicinal plant used since ancient times. Itsmucilage contains no less than 75 active ingredients with multiple properties. The present research aims to study the acute toxicity of the aqueous extract of A v gel (AEAVG) and to determine itsno-toxic effect dose (NTED). After the aqueous extraction of A v gel, an acute toxicity study was conducted in Swiss mice for 14 days by oral administration of AEAVG in a single dose (0, 250, 500, and 1000 mg/kg BW). Acute toxicity evaluation affected mouse behavior, weight gain, food and water intake, serum biochemical parameters (transaminases, urea, and albumin), and organ histology (liver and kidneys). These results show that the NTED is lower than 500 mg/kg BW. AEAVG has toxic effects at doses equal to or greater than 500 mg/kg BW, raising the alarm about the therapeutic use of AEAVG. Bangladesh J. Sci. Ind. Res. 58(1), 19-34, 2023
{"title":"Acute toxicity of the aqueous extract of Aloe barbadensis miller gel","authors":"F. Abderrahmane, S. Addou, I. Labadie, O. Kheroua","doi":"10.3329/bjsir.v58i1.65110","DOIUrl":"https://doi.org/10.3329/bjsir.v58i1.65110","url":null,"abstract":"Aloe vera (A v) is a medicinal plant used since ancient times. Itsmucilage contains no less than 75 active ingredients with multiple properties. The present research aims to study the acute toxicity of the aqueous extract of A v gel (AEAVG) and to determine itsno-toxic effect dose (NTED). After the aqueous extraction of A v gel, an acute toxicity study was conducted in Swiss mice for 14 days by oral administration of AEAVG in a single dose (0, 250, 500, and 1000 mg/kg BW). Acute toxicity evaluation affected mouse behavior, weight gain, food and water intake, serum biochemical parameters (transaminases, urea, and albumin), and organ histology (liver and kidneys). These results show that the NTED is lower than 500 mg/kg BW. AEAVG has toxic effects at doses equal to or greater than 500 mg/kg BW, raising the alarm about the therapeutic use of AEAVG.\u0000Bangladesh J. Sci. Ind. Res. 58(1), 19-34, 2023","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49579895","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 : 2023-03-27DOI: 10.3329/bjsir.v58i1.63634
Mahendra Kumar Gora, Arvind Kumar, B. L. Choudhary, S. N. Dolia, Sanjay Kumar, R. Singhal
We explored the impact of Gd doping on the structural, electronic and optical characteristics of the ZnO powder. The Gd-doped ZnO (0, 2% and 5%) powder samples have been synthesized using the conventional solid-state reaction process with varied Gd concentrations. The XRD pattern confirmed that all the studied samples are in the hexagonal wurtzite crystalline structure. The morphology has been explored using SEM images, which exhibited an agglomerated rod-like particle structure. The XPS results indicate the presence of oxygen vacancies (Vo) in the Gd-doped ZnO samples and the Vo’s are found to increase with increasing Gd amount. According to PL findings, the intensity ratio of the green and ultra-violet emission peaks is found to increase from 0.090 to 0.418 with increasing Gd-doping concentrations, confirming that Vo’s are increasing with Gd-doping. The UV-visible spectroscopy results reveal that the energy band gap (Eg) decreased from 3.31 eV to 3.23 eV with increasing Gd-doping concentration. Bangladesh J. Sci. Ind. Res. 58(1), 53-64, 2023
{"title":"Electronic, structural and optical properties of Gd-doped ZnO powder synthesized by solid-state reaction method","authors":"Mahendra Kumar Gora, Arvind Kumar, B. L. Choudhary, S. N. Dolia, Sanjay Kumar, R. Singhal","doi":"10.3329/bjsir.v58i1.63634","DOIUrl":"https://doi.org/10.3329/bjsir.v58i1.63634","url":null,"abstract":"We explored the impact of Gd doping on the structural, electronic and optical characteristics of the ZnO powder. The Gd-doped ZnO (0, 2% and 5%) powder samples have been synthesized using the conventional solid-state reaction process with varied Gd concentrations. The XRD pattern confirmed that all the studied samples are in the hexagonal wurtzite crystalline structure. The morphology has been explored using SEM images, which exhibited an agglomerated rod-like particle structure. The XPS results indicate the presence of oxygen vacancies (Vo) in the Gd-doped ZnO samples and the Vo’s are found to increase with increasing Gd amount. According to PL findings, the intensity ratio of the green and ultra-violet emission peaks is found to increase from 0.090 to 0.418 with increasing Gd-doping concentrations, confirming that Vo’s are increasing with Gd-doping. The UV-visible spectroscopy results reveal that the energy band gap (Eg) decreased from 3.31 eV to 3.23 eV with increasing Gd-doping concentration.\u0000Bangladesh J. Sci. Ind. Res. 58(1), 53-64, 2023","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46436077","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.63377
M. Uddin, Sk Ray, MS Islam, M. Karim, M. Jahan
The study has attempted to develop chemometric modeling based method to quantify compositions of textile fabrics by FT-NIR spectroscopic data. Three calibration techniques such as: Principal Component Regression (PCR), Partial Least Square Regression (PLSR) and Artificial Neural Network (ANN) were assessed, and PLSR showed the best result. Several pretreatment techniques of spectral data have been evaluated, and Multiplicative Scatter Correction (MSC) performed the best. Results also shows that performance of PLSR was satisfactory for quantification of cotton (R2 ≈0.99), elastine (R2 ≈0.97) and polyester (R2≈0.94) when FT-NIR spectral data were pretreated with MSC. But for quantification of viscose in mixture fabric, efficiency of developed model was not upto the mark (R2≈0.75). Finally, the developed PLSR model with FT-NIR spectroscopic data pretreated with MSC could be used for quantification of cotton, elastine and polyester in textile fabrics rapidly and with comparatively low cost. Bangladesh J. Sci. Ind. Res. 57(4), 229-238, 2022
{"title":"Quantification of components of textile fabrics by using chemometric techniques with FT-NIR spectroscopic data","authors":"M. Uddin, Sk Ray, MS Islam, M. Karim, M. Jahan","doi":"10.3329/bjsir.v57i4.63377","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.63377","url":null,"abstract":"The study has attempted to develop chemometric modeling based method to quantify compositions of textile fabrics by FT-NIR spectroscopic data. Three calibration techniques such as: Principal Component Regression (PCR), Partial Least Square Regression (PLSR) and Artificial Neural Network (ANN) were assessed, and PLSR showed the best result. Several pretreatment techniques of spectral data have been evaluated, and Multiplicative Scatter Correction (MSC) performed the best. Results also shows that performance of PLSR was satisfactory for quantification of cotton (R2 ≈0.99), elastine (R2 ≈0.97) and polyester (R2≈0.94) when FT-NIR spectral data were pretreated with MSC. But for quantification of viscose in mixture fabric, efficiency of developed model was not upto the mark (R2≈0.75). Finally, the developed PLSR model with FT-NIR spectroscopic data pretreated with MSC could be used for quantification of cotton, elastine and polyester in textile fabrics rapidly and with comparatively low cost.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 229-238, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47413989","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.61400
Chukwuedozie N. Ezema, Nnenna Harmony Nwobodo-Nzeribe, J. Eneh, Uche Chinweoke Ogbuefi, M. J. Mbunwe, B. Anyaka, J. N. Ngene
The study assessed manufacturing system optimization using computer-based control kanban loops. The study assessed JIT's effect on average throughput-time, demand fill rate, net operating income for a certain product mix complexity and manufacturing overhead level. ARENA/SIMAN and WITNESS simulation tools were used to study implementation. The Drug Process Plant's JIT system reduced end buffer inventory, shortened customer lead time, and improved visual control. The mean response of the simulated new physical system in terms of NOI was 85.54 but gave a mean response of 85.30 when implemented on the shop floor. The mean response of the simulated new physical system in terms of cycle time was 617 but gave a mean response of 634 when implemented on the shop floor. Simulated new physical system in terms of DFR gave a mean response of 93.11 when implemented on the shop floor. Overwhelmingly, the new JIT system outperformed the old physical system. Bangladesh J. Sci. Ind. Res. 57(4), 221-228, 2022
{"title":"Manufacturing system optimization using computer-based control kanban loops","authors":"Chukwuedozie N. Ezema, Nnenna Harmony Nwobodo-Nzeribe, J. Eneh, Uche Chinweoke Ogbuefi, M. J. Mbunwe, B. Anyaka, J. N. Ngene","doi":"10.3329/bjsir.v57i4.61400","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.61400","url":null,"abstract":"The study assessed manufacturing system optimization using computer-based control kanban loops. The study assessed JIT's effect on average throughput-time, demand fill rate, net operating income for a certain product mix complexity and manufacturing overhead level. ARENA/SIMAN and WITNESS simulation tools were used to study implementation. The Drug Process Plant's JIT system reduced end buffer inventory, shortened customer lead time, and improved visual control. The mean response of the simulated new physical system in terms of NOI was 85.54 but gave a mean response of 85.30 when implemented on the shop floor. The mean response of the simulated new physical system in terms of cycle time was 617 but gave a mean response of 634 when implemented on the shop floor. Simulated new physical system in terms of DFR gave a mean response of 93.11 when implemented on the shop floor. Overwhelmingly, the new JIT system outperformed the old physical system.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 221-228, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46757945","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.63376
Y. Mahmud, Maryam Razzaq
Shoe lining leather that remains under the upper material deserves a comparative evaluation to bring positive outcomes and finding out best possible practice in terms of quality, comfort and other relevant properties for shoe manufactured in different regions. Focusing on this point, a study were performed where lining leathers made of goat skins were collected from a number of footwear factories situated at different parts of Dhaka city and its suburb. To examine the collected lining leathers their physical and chemical properites were studied. Physical evaluation parameters were flexing endurance, tensile strength, stich tear strenth, water vapor permeability shrinkage temperature, color fastness and perspiration fastness. Chemical evaluation parameters were limited to determination of chromic oxide content, fat content and total sulphated ash content. Finally, a compartive study chart has been depicted based on the assessed qualities of collected samples. Bangladesh J. Sci. Ind. Res. 57(4), 207-214, 2022
{"title":"Quality assessment of shoe lining leather collected from a few footwear factories","authors":"Y. Mahmud, Maryam Razzaq","doi":"10.3329/bjsir.v57i4.63376","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.63376","url":null,"abstract":"Shoe lining leather that remains under the upper material deserves a comparative evaluation to bring positive outcomes and finding out best possible practice in terms of quality, comfort and other relevant properties for shoe manufactured in different regions. Focusing on this point, a study were performed where lining leathers made of goat skins were collected from a number of footwear factories situated at different parts of Dhaka city and its suburb. To examine the collected lining leathers their physical and chemical properites were studied. Physical evaluation parameters were flexing endurance, tensile strength, stich tear strenth, water vapor permeability shrinkage temperature, color fastness and perspiration fastness. Chemical evaluation parameters were limited to determination of chromic oxide content, fat content and total sulphated ash content. Finally, a compartive study chart has been depicted based on the assessed qualities of collected samples.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 207-214, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44631491","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.62651
MS Islam, MA Al Mansur, SA Rakhi, M. Sarkar, M. Kuddus, F. Ahmed
Vitex peduncularis (Verbenaceae), a perennial tree, is locally utilized for possessing multifaceted pharmacological properties including analgesic, antimalarial, anti-angina, antidiabetic, antioxidant, anti-inflammatory and hepatoprotective. Hence, this study aims to evaluate their antioxidant, thrombolytic, cytotoxic and antibacterial activities from the methanolic crude extract and its various solvent fractions. Data from antioxidant and thrombolytic assay displayed that Kupchan partitioned chloroform soluble fraction revealed the maximum phenolic content (73.39 mg of GAE/g of extract), DPPH free radical scavenging activity (26.69 μg/ml) and thrombolytic activity (37.35%). In brine shrimp lethality evaluation, the LC50 values indicate that the most cytotoxic compound was found to be from ethyl acetate soluble fraction (LC50 6.73 μg/ml). Finally, antibacterial activity of different fractions showed that both chloroform and methanolic fraction possessed mild activity against the tested bacteria. The potential biological effects of the crude fractions have been demonstrated demanding future studies of the isolated compounds to assess these activities. Bangladesh J. Sci. Ind. Res. 57(4), 239-246, 2022
{"title":"Antioxidant, thrombolytic, cytotoxic and antibacterial activities of leaves of Vitex peduncularis","authors":"MS Islam, MA Al Mansur, SA Rakhi, M. Sarkar, M. Kuddus, F. Ahmed","doi":"10.3329/bjsir.v57i4.62651","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.62651","url":null,"abstract":"Vitex peduncularis (Verbenaceae), a perennial tree, is locally utilized for possessing multifaceted pharmacological properties including analgesic, antimalarial, anti-angina, antidiabetic, antioxidant, anti-inflammatory and hepatoprotective. Hence, this study aims to evaluate their antioxidant, thrombolytic, cytotoxic and antibacterial activities from the methanolic crude extract and its various solvent fractions. Data from antioxidant and thrombolytic assay displayed that Kupchan partitioned chloroform soluble fraction revealed the maximum phenolic content (73.39 mg of GAE/g of extract), DPPH free radical scavenging activity (26.69 μg/ml) and thrombolytic activity (37.35%). In brine shrimp lethality evaluation, the LC50 values indicate that the most cytotoxic compound was found to be from ethyl acetate soluble fraction (LC50 6.73 μg/ml). Finally, antibacterial activity of different fractions showed that both chloroform and methanolic fraction possessed mild activity against the tested bacteria. The potential biological effects of the crude fractions have been demonstrated demanding future studies of the isolated compounds to assess these activities.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 239-246, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44329163","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.59704
S. Sivaramanan, S. Kotagama
The MV Xpress-Pearl ship disaster was a maritime environmental security threat that occurred on the Southwest coast of Sri Lanka during this decade. The wreck consists of tonnes of nitric acid, several other chemicals, and oils such as tonnes of bunker fuel oil, gas oil, and tanks full of lubricating oil. Also, several containers occupied with plastic nurdles that escaped have affected the west and southern coastal belt of Sri Lanka. Carcasses of dead endangered turtles, dolphins and various other rare marine organisms washed ashore, such as beaches of Uswetakeiyawa, Panadura, Unawatuna, Wellawatte, Moratuwa, and Induruwa. Besides, experts believe that it may take a long term to completely recover from the impacts including safe plastic nurdle-free seafood. Green peace USA has purported a list of conditions to be updated, such as the implementation of the plastic pallet free water act and placing plastics into the hazardous material category. The study used the qualitative content analysis technique to reconcile plastic pollution caused by the disaster as an environmental problem. Since plastic pollution is also a repercussion of two known keystone environmental problems, such as urbanization and human population increase. Bangladesh J. Sci. Ind. Res. 57(4), 199-206, 2022
{"title":"Ship disaster threatened environmental security and dwindled down the spirit of maritime Sri Lanka","authors":"S. Sivaramanan, S. Kotagama","doi":"10.3329/bjsir.v57i4.59704","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.59704","url":null,"abstract":"The MV Xpress-Pearl ship disaster was a maritime environmental security threat that occurred on the Southwest coast of Sri Lanka during this decade. The wreck consists of tonnes of nitric acid, several other chemicals, and oils such as tonnes of bunker fuel oil, gas oil, and tanks full of lubricating oil. Also, several containers occupied with plastic nurdles that escaped have affected the west and southern coastal belt of Sri Lanka. Carcasses of dead endangered turtles, dolphins and various other rare marine organisms washed ashore, such as beaches of Uswetakeiyawa, Panadura, Unawatuna, Wellawatte, Moratuwa, and Induruwa. Besides, experts believe that it may take a long term to completely recover from the impacts including safe plastic nurdle-free seafood. Green peace USA has purported a list of conditions to be updated, such as the implementation of the plastic pallet free water act and placing plastics into the hazardous material category. The study used the qualitative content analysis technique to reconcile plastic pollution caused by the disaster as an environmental problem. Since plastic pollution is also a repercussion of two known keystone environmental problems, such as urbanization and human population increase.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 199-206, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48834656","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 : 2022-12-25DOI: 10.3329/bjsir.v57i4.58987
M. Mosallem, Haitham M. Hadidi, Mohammed Y. Tharwan, Zeinab A. Ahmed
The flow over compound cylinders is simulated using computational fluid dynamic (CFD). Three contacting cylinders of different diameters, arranged in tandem with respect to the oncoming flow were examined at Reynolds number ReD = 333 based on the diameter of the middle cylinder, D. The proposed configuration simulates the wind flow over the satellite launch vehicles during the period of launch. Computations were performed for diameter-to-diameter ratio, d / D, of 0.8 and 0.6. The numerical results revealed the vortex formation and vortex shedding mechanism in the wake downstream of the cylinders. For d / D = 0.6, the near wake is wider than that of d / D = 0.8. It is also found that the base pressure coefficient values for d / D = 0.6 are lower than those for d / D = 0.8. These findings imply that the acting drag force on the cylinders for d / D = 0.6 is larger than that for d / D = 0.8. Concluding that, the base pressure coefficient depends on the diameter ratio d / D whereas, the computed vortex-shedding Strouhal number value was found to be 0.25 and is independent on the d / D ratio. Bangladesh J. Sci. Ind. Res. 57(4), 215-220, 2022
采用计算流体力学(CFD)方法对复合气缸的流动进行了数值模拟。在雷诺数ReD = 333的条件下，以中间圆柱的直径d为基础，研究了三个不同直径的接触圆柱相对于迎面流串联布置的情况，所提出的构型模拟了卫星运载火箭发射期间的气流。计算径径比d / d分别为0.8和0.6。数值结果揭示了旋涡的形成和旋涡脱落机理。当d / d = 0.6时，近尾迹比d / d = 0.8时宽。d / d = 0.6时的基压系数值低于d / d = 0.8时的基压系数值。这些结果表明，当d / d = 0.6时，作用在气缸上的阻力大于d / d = 0.8时。由此得出，基压系数与直径比d / d有关，而计算得到的涡脱斯特罗哈尔数值为0.25，与直径比d / d无关。[j]。判例57(4)，215-220,2022
{"title":"Numerical study of unsteady flow past compound cylinders","authors":"M. Mosallem, Haitham M. Hadidi, Mohammed Y. Tharwan, Zeinab A. Ahmed","doi":"10.3329/bjsir.v57i4.58987","DOIUrl":"https://doi.org/10.3329/bjsir.v57i4.58987","url":null,"abstract":"The flow over compound cylinders is simulated using computational fluid dynamic (CFD). Three contacting cylinders of different diameters, arranged in tandem with respect to the oncoming flow were examined at Reynolds number ReD = 333 based on the diameter of the middle cylinder, D. The proposed configuration simulates the wind flow over the satellite launch vehicles during the period of launch. Computations were performed for diameter-to-diameter ratio, d / D, of 0.8 and 0.6. The numerical results revealed the vortex formation and vortex shedding mechanism in the wake downstream of the cylinders. For d / D = 0.6, the near wake is wider than that of d / D = 0.8. It is also found that the base pressure coefficient values for d / D = 0.6 are lower than those for d / D = 0.8. These findings imply that the acting drag force on the cylinders for d / D = 0.6 is larger than that for d / D = 0.8. Concluding that, the base pressure coefficient depends on the diameter ratio d / D whereas, the computed vortex-shedding Strouhal number value was found to be 0.25 and is independent on the d / D ratio.\u0000Bangladesh J. Sci. Ind. Res. 57(4), 215-220, 2022","PeriodicalId":8735,"journal":{"name":"Bangladesh Journal of Scientific and Industrial Research","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48497749","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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