Pub Date : 2021-09-28DOI: 10.52763/PJSIR.PHYS.SCI.64.3.2021.191.194
M. N. Khan, M. Khan, Noreen Aslam, Pir Bakhsh Khan, E. Haq
7-benzylideneamino-5H-thiochromeno[2,3-b]pyridin-5-ones and 9-benzylideneamino-5H-thio- chromeno[2,3-b]pyridin-5-ones, on reaction with ethyl pyruvate to afford 1-ethoxycarbonyl-3-phenyl-12H- pyrido[3',2':5,6]thiopyrano[3,2-f]quinoline-12-ones and 4-ethoxycarbonyl-2-phenyl-7H- pyrido[3',2':5,6]thiopyrano[3,2-h]quinoline-7-ones respectively by the two different methods. These products were precipitated by addition of ethanol, water (1:1), were purified by recrystalizing from appropriate solvents and were characterized from their IR, 1H-NMR, mass spectra and elemental analysis data.
{"title":"Tetracyclic Heteroaromatic Systems-Synthesis of Ethoxycarbonylphenylpyrido[3',2':5,6] Thiopyranoquinolines","authors":"M. N. Khan, M. Khan, Noreen Aslam, Pir Bakhsh Khan, E. Haq","doi":"10.52763/PJSIR.PHYS.SCI.64.3.2021.191.194","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.3.2021.191.194","url":null,"abstract":"7-benzylideneamino-5H-thiochromeno[2,3-b]pyridin-5-ones and 9-benzylideneamino-5H-thio- chromeno[2,3-b]pyridin-5-ones, on reaction with ethyl pyruvate to afford 1-ethoxycarbonyl-3-phenyl-12H- pyrido[3',2':5,6]thiopyrano[3,2-f]quinoline-12-ones and 4-ethoxycarbonyl-2-phenyl-7H- pyrido[3',2':5,6]thiopyrano[3,2-h]quinoline-7-ones respectively by the two different methods. These products were precipitated by addition of ethanol, water (1:1), were purified by recrystalizing from appropriate solvents and were characterized from their IR, 1H-NMR, mass spectra and elemental analysis data. \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80705207","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 : 2021-07-06DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.173.190
A. Riaz, I. Pasha, M. Sharif, Sadaf Javaria
The most prevalent exposure of bisphenol A (BPA) to biological systems has directed health organizations to reduce its safe dosage and the stringent regulation by developed countries that led to ban of BPA-based (Bisphenol analogues) baby bottles. This in turn has opened a new window for ongoing entry of bisphenol analogues into consumer market. Recently, there has been tremendous growth in both production and application of bisphenol analogues to achieve the "BPA-free" claim. Nevertheless, due to growing epidemiological evidence concerning the toxicological effects of these bisphenol analogues in both in vivo and in vitro systems, the debate regarding the safety concerns over bisphenols is back. Structural analogues of bisphenol A had been identified in food products, human and environment matrices. Present review is an attempt to recapitulate the presence of bisphenols in food and environment matrices as well as their concerning physiological effects in animal models and human groups. But, due to structural analogy of these substitutes, their endpoints on biological functions are comparable to original compound or in certain situations, more harmful than original compound. Unfortunately, other potentially harmful alternatives are emerging and it is therefore advised that the replacement of bisphenol A with other structural analogues must be executed with great care.
{"title":"Bisphenol A and its Analogues: Human Exposure and Biological Effects-A Review","authors":"A. Riaz, I. Pasha, M. Sharif, Sadaf Javaria","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.173.190","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.173.190","url":null,"abstract":" The most prevalent exposure of bisphenol A (BPA) to biological systems has directed health organizations to reduce its safe dosage and the stringent regulation by developed countries that led to ban of BPA-based (Bisphenol analogues) baby bottles. This in turn has opened a new window for ongoing entry of bisphenol analogues into consumer market. Recently, there has been tremendous growth in both production and application of bisphenol analogues to achieve the \"BPA-free\" claim. Nevertheless, due to growing epidemiological evidence concerning the toxicological effects of these bisphenol analogues in both in vivo and in vitro systems, the debate regarding the safety concerns over bisphenols is back. Structural analogues of bisphenol A had been identified in food products, human and environment matrices. Present review is an attempt to recapitulate the presence of bisphenols in food and environment matrices as well as their concerning physiological effects in animal models and human groups. But, due to structural analogy of these substitutes, their endpoints on biological functions are comparable to original compound or in certain situations, more harmful than original compound. Unfortunately, other potentially harmful alternatives are emerging and it is therefore advised that the replacement of bisphenol A with other structural analogues must be executed with great care.","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83076128","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 : 2021-07-06DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.161.172
M. Majid, Muhammad Ibrahim Khan
Conventional buildings consume large amounts of energy and are the source of greenhouse gas emissions contributing to climate change. The shortage of green buildings in Pakistan have been said to be due to shortage of knowledge of the benefits of essential green building materials and the absence of a regulatory framework. The study is qualitative and quantitative and is divided into two parts. This review paper focuses on awareness in the Pakistan's local construction market concerning green buildings through a survey questionnaire. Data collection procedure consists of 60 questionnaires related to green building construction awareness and priorities within Karachi's construction sector. Also, a focus group and personal interviews conducted with at least 5 professionals working in local construction projects are analyzed. The research questions formed from detailed literature review were analyzed and found that energy conservation, environmental/resource conservation and improving indoor environmental quality are major driving factors for green building development. Similarly, there is a lack of knowledge of green construction methods and regulations and lack of support from the government. This has been found as the major barrier in going towards green construction. We recommend policy directions towards this end and elaborate points of concern to the authorities.
{"title":"Techno-Economic Analysis of Green Construction Regulations Plus Survey for Prototype Implementation in Karachi","authors":"M. Majid, Muhammad Ibrahim Khan","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.161.172","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.161.172","url":null,"abstract":" \u0000Conventional buildings consume large amounts of energy and are the source of greenhouse gas emissions contributing to climate change. The shortage of green buildings in Pakistan have been said to be due to shortage of knowledge of the benefits of essential green building materials and the absence of a regulatory framework. The study is qualitative and quantitative and is divided into two parts. This review paper focuses on awareness in the Pakistan's local construction market concerning green buildings through a survey questionnaire. Data collection procedure consists of 60 questionnaires related to green building construction awareness and priorities within Karachi's construction sector. Also, a focus group and personal interviews conducted with at least 5 professionals working in local construction projects are analyzed. The research questions formed from detailed literature review were analyzed and found that energy conservation, environmental/resource conservation and improving indoor environmental quality are major driving factors for green building development. Similarly, there is a lack of knowledge of green construction methods and regulations and lack of support from the government. This has been found as the major barrier in going towards green construction. We recommend policy directions towards this end and elaborate points of concern to the authorities. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"106 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77278677","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.149.160
T. Iqbal, M. Zafar, M. Ijaz
Nuclear energy is the most important source to produce electricity. The production processes are very important for reducing risks and increasing the efficiency. Nano-fluids also have the potential to transfer heat with improved thermo-physical properties which can be applicable in many devices for better performance. Advancement in nanotechnology develops new fluids which transfer heat called nano-fluids. So, for heat exchange in the core of nuclear reactors, nano-fluids are used because of their unique heat transfer properties. For significant improvement in properties, the modest concentration of nano-particles is required. Recent research is more about behaviour of nano-fluids to utilize their unique properties. Heat transfer property is very important for industrial applications, nuclear reactors, transportation, and electronics and also in biomedicine. Nano-fluid acts like smart fluid, where heat transfer property can be controlled. This review establishes a focus on the wide range of recent and future uses about nano-fluids, related to their improved properties of heat transfer that may be controllable and other specific properties of nano- fluids.
{"title":"Use of Nano Fluids in Nuclear Technology: A Review","authors":"T. Iqbal, M. Zafar, M. Ijaz","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.149.160","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.149.160","url":null,"abstract":"Nuclear energy is the most important source to produce electricity. The production processes are very important for reducing risks and increasing the efficiency. Nano-fluids also have the potential to transfer heat with improved thermo-physical properties which can be applicable in many devices for better performance. Advancement in nanotechnology develops new fluids which transfer heat called nano-fluids. So, for heat exchange in the core of nuclear reactors, nano-fluids are used because of their unique heat transfer properties. For significant improvement in properties, the modest concentration of nano-particles is required. Recent research is more about behaviour of nano-fluids to utilize their unique properties. Heat transfer property is very important for industrial applications, nuclear reactors, transportation, and electronics and also in biomedicine. Nano-fluid acts like smart fluid, where heat transfer property can be controlled. This review establishes a focus on the wide range of recent and future uses about nano-fluids, related to their improved properties of heat transfer that may be controllable and other specific properties of nano- fluids. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77612357","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.103.109
W. Ahmad, A. Zubair, H. Abbasi, M. Nasir
This study was conducted to investigate the water quality of the Indus river, Sindh, Pakistan. A total of 41 locations were selected along the Indus river and its tributaries for the collection of surface water samples. Twenty-one physico-chemical parameters and heavy metals were analyzed and the data were interpreted through different statistical techniques. In the current study, eleven parameters including iron, copper, zinc, electrical conductivity (EC), total dissolved solids (TDS), pH, potassium, sodium, nitrate, sulfate, and chloride with an average value 0.13 mg/L, 0.04 mg/L, 0.16 mg/L, 733 µS/L, 211.2 mg/L, 7.6, 8.9 mg/L, 107.4 mg/L, 8.01 mg/L, 102 mg/L, 140 mg/L respectively and were within permissible limits set by the World Health Organization (WHO) for drinking water. Whereas, average values of cadmium, mercury, lead, total alkalinity (TA), chemical oxygen demand (COD), total hardness (TH) and turbidity were found 0.004 mg/L, 0.007 mg/L, 0.02 mg/L, 920 mg/L, 103 mg/L, 262 mg/L and 186.2 NTU respectively, higher than permissible limits. Pearson correlation matrix and cluster analysis were used to understand similarities and differences between variables. The variation in the correlation of different parameters shows the complexity of the water quality.
{"title":"Water Study of Physical, Chemical and Heavy Metals Parameters in River Indus and its Tributaries, Sindh, Pakistan","authors":"W. Ahmad, A. Zubair, H. Abbasi, M. Nasir","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.103.109","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.103.109","url":null,"abstract":"This study was conducted to investigate the water quality of the Indus river, Sindh, Pakistan. A total of 41 locations were selected along the Indus river and its tributaries for the collection of surface water samples. Twenty-one physico-chemical parameters and heavy metals were analyzed and the data were interpreted through different statistical techniques. In the current study, eleven parameters including iron, copper, zinc, electrical conductivity (EC), total dissolved solids (TDS), pH, potassium, sodium, nitrate, sulfate, and chloride with an average value 0.13 mg/L, 0.04 mg/L, 0.16 mg/L, 733 µS/L, 211.2 mg/L, 7.6, \u00008.9 mg/L, 107.4 mg/L, 8.01 mg/L, 102 mg/L, 140 mg/L respectively and were within permissible limits set by the World Health Organization (WHO) for drinking water. Whereas, average values of cadmium, mercury, lead, total alkalinity (TA), chemical oxygen demand (COD), total hardness (TH) and turbidity were found 0.004 mg/L, 0.007 mg/L, 0.02 mg/L, 920 mg/L, 103 mg/L, 262 mg/L and 186.2 NTU respectively, higher than permissible limits. Pearson correlation matrix and cluster analysis were used to understand similarities and differences between variables. The variation in the correlation of different parameters shows the complexity of the water quality. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"200 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78180542","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.131.136
Muhammad Bilal, M. Z. Emad, Fawad Ul Hassan, Zaheer Ahmed
This research work presents the rock mass characteristics and tunnel support system recommendations for hydroelectric power tunnels at Dasu dam site Pakistan. Two inverted U-shaped tunnels are proposed at the left bank of Indus river. The tunnels have inlet portals at an elevation of 773.00 m and outlet portals at an elevation of 758.00 m. The thickness of rock cover above the tunnels is between 100 and 200 m. Three types of rock are encountered at project site including Granulite, Amphibolite and Gabbronorite. Granulite rocks are encountered along the alignment of tunnels. Rock mass is classified using Rock mass rating (RMR) and Tunneling quality index (Q system). Support system is suggested based on values of Q and RMR. Correlation between Q-index and RMR is also derived.
{"title":"Empirical Support Design for Proposed Diversion Tunnels at Dasu Dam Site Pakistan","authors":"Muhammad Bilal, M. Z. Emad, Fawad Ul Hassan, Zaheer Ahmed","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.131.136","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.131.136","url":null,"abstract":" \u0000This research work presents the rock mass characteristics and tunnel support system recommendations for hydroelectric power tunnels at Dasu dam site Pakistan. Two inverted U-shaped tunnels are proposed at the left bank of Indus river. The tunnels have inlet portals at an elevation of 773.00 m and outlet portals at an elevation of 758.00 m. The thickness of rock cover above the tunnels is between 100 and 200 m. Three types of rock are encountered at project site including Granulite, Amphibolite and Gabbronorite. Granulite rocks are encountered along the alignment of tunnels. Rock mass is classified using Rock mass rating (RMR) and Tunneling quality index (Q system). Support system is suggested based on values of Q and RMR. Correlation between Q-index and RMR is also derived. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87998074","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.137.148
S. Hussain, Han Feng-qing, Ma Yunqi, H. Khan, Yang Jian, Gulfam Hussain, D. Widory
Rock salt is of importance for both humans and industries. In this study, we discussed the main salt deposits in Pakistan by evaluating the total reserves as well as the rock salt annual production and by characterizing their chemical composition (Na+, Ca2+, Mg2+, K+, B+, K+, Li+, Cl-, SO42-, Br- and NO3-). Our objectives were to document their impurity, water-insoluble matter and moisture contents to ultimately discuss whether the halite in Pakistan, in its natural form, is safe for human consumption. Pakistan rock salt deposits are located in two distinct regions: the Salt Range area in the Potwar sub-basin with huge Precambrian salt deposits and the Eocene Bahadurkhel/Kohat salts in the Kohat sub-basin. Total reserves are estimated over tens of billion tons with an annual production of about 3,534,075 metric tons in 2017-Results show that the halite of the salt range area is purer than the Bahadurkhel/Kohat salts with purity levels (expressed as NaCl) of 99 and 95 wt. %, respectively. Gypsum represents one of the main impurities in halite for both regions, while potash salts (>9 wt. %) are observed in the Salt Range area, K contents are very low in the Kohat salts. Although the halite moisture content is similar for both regions, impurities contents are higher (>5%) for the Kohat salts, arising the need for their purification prior to eventual human consumption.
{"title":"An Overview of Pakistan Rock Salt Resources and Their Chemical Characterization","authors":"S. Hussain, Han Feng-qing, Ma Yunqi, H. Khan, Yang Jian, Gulfam Hussain, D. Widory","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.137.148","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.137.148","url":null,"abstract":"Rock salt is of importance for both humans and industries. In this study, we discussed the main salt deposits in Pakistan by evaluating the total reserves as well as the rock salt annual production and by characterizing their chemical composition (Na+, Ca2+, Mg2+, K+, B+, K+, Li+, Cl-, SO42-, Br- and NO3-). Our objectives were to document their impurity, water-insoluble matter and moisture contents to ultimately discuss whether the halite in Pakistan, in its natural form, is safe for human consumption. Pakistan rock salt deposits are located in two distinct regions: the Salt Range area in the Potwar sub-basin with huge Precambrian salt deposits and the Eocene Bahadurkhel/Kohat salts in the Kohat sub-basin. Total reserves are estimated over tens of billion tons with an annual production of about 3,534,075 metric tons in 2017-Results show that the halite of the salt range area is purer than the Bahadurkhel/Kohat salts with purity levels (expressed as NaCl) of 99 and 95 wt. %, respectively. Gypsum represents one of the main impurities in halite for both regions, while potash salts (>9 wt. %) are observed in the Salt Range area, K contents are very low in the Kohat salts. Although the halite moisture content is similar for both regions, impurities contents are higher (>5%) for the Kohat salts, arising the need for their purification prior to eventual human consumption. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75296371","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.119.130
A. Imran, S. Ahmed, Waqar Ahmed, M. Zia-ur-Rehman, Arif Iqbal, N. Ahmad, Irfan Ullah
Forest biomass estimation is the central part of sustainable forest management to assess carbon stocks and carbon emissions from forest ecosystem. Sentinel-2 is state-of-art sensor with refined spatial and recurrent temporal resolution data. The present study explored the potential of Sentinel-2 derived vegetation indices for above ground biomass prediction using four regression models (linear, exponential, power and logarithmic). Sentinel-2 indices includes Global environmental monitoring index, transformed normalized difference vegetation index, normalized difference water index, normalized difference infrared index and red-edge normalized difference vegetation index. The performances of Sentinel-2 indices were assessed by simple single variable (index) based regression for GEMI, TNDVI, NDII, NDWI and RENDVI versus AGB values. Further, stepwise linear regression was also developed in which used all indices entered into stepwise selection and the best index was selected in the final model. Results showed that linear model of all indices performance best compared to the rest three models and R2 values 0.12, 0.39, 0.46, 0.44 and 0.37 for Global environmental monitoring index, transformed normalized. Vegetation index, normalized difference water index, infrared index and red-edge vegetation index, respectively. Normalized difference water index was considered the best index among five computed indices in simple linear as well as in stepwise linear regression, whereas rest of the indices were removed because they were not significant under the stepwise criteria. Further, the accuracy of normalized difference water index model was determined by root mean square error and final prediction model has 28.27 t/ha error for both simple linear and stepwise linear regression. Therefore, normalized difference water index was selected for biomass mapping and resultant biomass showed up to 339 t/ha in the study area. The resultant biomass map also showed consistency with global datasets which include global forest canopy height and global forest tree cover change maps. The study suggest that Sentinel-2 product has great potential to estimate above ground biomass with accuracy and can be used for large scale mapping in combination with national forest inventory for carbon emission accounting.
{"title":"Integration of Sentinel-2 Derived Spectral Indices and In-situ Forest Inventory to Predict Forest Biomass","authors":"A. Imran, S. Ahmed, Waqar Ahmed, M. Zia-ur-Rehman, Arif Iqbal, N. Ahmad, Irfan Ullah","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.119.130","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.119.130","url":null,"abstract":" \u0000Forest biomass estimation is the central part of sustainable forest management to assess carbon stocks and carbon emissions from forest ecosystem. Sentinel-2 is state-of-art sensor with refined spatial and recurrent temporal resolution data. The present study explored the potential of Sentinel-2 derived vegetation indices for above ground biomass prediction using four regression models (linear, exponential, power and logarithmic). Sentinel-2 indices includes Global environmental monitoring index, transformed normalized difference vegetation index, normalized difference water index, normalized difference infrared index and red-edge normalized difference vegetation index. The performances of Sentinel-2 indices were assessed by simple single variable (index) based regression for GEMI, TNDVI, NDII, NDWI and RENDVI versus AGB values. Further, stepwise linear regression was also developed in which used all indices entered into stepwise selection and the best index was selected in the final model. Results showed that linear model of all indices performance best compared to the rest three models and R2 values 0.12, 0.39, 0.46, 0.44 and 0.37 for Global environmental monitoring index, transformed normalized. Vegetation index, normalized difference water index, infrared index and red-edge vegetation index, respectively. Normalized difference water index was considered the best index among five computed indices in simple linear as well as in stepwise linear regression, whereas rest of the indices were removed because they were not significant under the stepwise criteria. Further, the accuracy of normalized difference water index model was determined by root mean square error and final prediction model has 28.27 t/ha error for both simple linear and stepwise linear regression. Therefore, normalized difference water index was selected for biomass mapping and resultant biomass showed up to 339 t/ha in the study area. The resultant biomass map also showed consistency with global datasets which include global forest canopy height and global forest tree cover change maps. The study suggest that Sentinel-2 product has great potential to estimate above ground biomass with accuracy and can be used for large scale mapping in combination with national forest inventory for carbon emission accounting. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84685557","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.110.118
Kamran Baksh Soomro, S. Alaghmand, M. M. Shaikh, S. Andriyas, A. Talei
The salinity of soil is a crucial challenge for growers irrigating in semi-arid zones. To accomplish salinity, growers require information about salt's basis and processes of the salt mobility through the root zone. Soil salinity can be managed by exceptional irrigating farming practices including irrigation scheduling to leach down salts through the root zone. This study aimed at examining the salts movement in saline soil in a semi-arid region in Sindh, Pakistan. This field experiment was conducted during the summer of 2017 on a salt-affected land by using three irrigation treatments of canal water including T1 (7 day irrigation interval), T2 (14 day irrigation interval) and T3 (21 days irrigation interval) under 10, 9 and 8 cm depths of irrigation water, respectively. The texture of soil was silty clay loam having an electrical conductivity (EC) ranging from 7.73 to 20.69 dS/m. However, the pH of the soil ranged from 7.89 to 8.04. The findings of a two-way analysis of variance were consistent with the statistical examination of EC and pH data day- wise (7, 14 and 21 days) and depths-wise (10, 9 and 8 cm). Average reductions in the EC and pH of the soil were observed at 7 days interval and 10cm depth at P<0.05. Overall, the findings exhibited that, compared to the 14 and 21 day intervals, a 7 day irrigation interval was more effective in terms of salt leaching from the soil profile.
{"title":"Response of Salts in Saline Soil Using Different Irrigation Scheduling in Semi-Arid Zone of Pakistan","authors":"Kamran Baksh Soomro, S. Alaghmand, M. M. Shaikh, S. Andriyas, A. Talei","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.110.118","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.110.118","url":null,"abstract":"The salinity of soil is a crucial challenge for growers irrigating in semi-arid zones. To accomplish salinity, growers require information about salt's basis and processes of the salt mobility through the root zone. Soil salinity can be managed by exceptional irrigating farming practices including irrigation scheduling to leach down salts through the root zone. This study aimed at examining the salts movement in saline soil in a semi-arid region in Sindh, Pakistan. This field experiment was conducted during the summer of 2017 on a salt-affected land by using three irrigation treatments of canal water including T1 (7 day irrigation interval), T2 (14 day irrigation interval) and T3 (21 days irrigation interval) under 10, 9 and 8 cm depths of irrigation water, respectively. The texture of soil was silty clay loam having an electrical conductivity (EC) ranging from 7.73 to 20.69 dS/m. However, the pH of the soil ranged from 7.89 to 8.04. The findings of a two-way analysis of variance were consistent with the statistical examination of EC and pH data day- wise (7, 14 and 21 days) and depths-wise (10, 9 and 8 cm). Average reductions in the EC and pH of the soil were observed at 7 days interval and 10cm depth at P<0.05. Overall, the findings exhibited that, compared to the 14 and 21 day intervals, a 7 day irrigation interval was more effective in terms of salt leaching from the soil profile. \u0000 \u0000 ","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"94 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85511841","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 : 2021-07-05DOI: 10.52763/PJSIR.PHYS.SCI.64.2.2021.97.102
A. Mushtaq, H. Mukhtar, A. Shariff
This study was carried out to evaluate the effect of blending the rubbery and glassy polymer with an alkanolamine on the mechanical properties. Due to the intrinsic properties of glassy polysulfone (PSU) and rubbery polyvinyl acetate (PVAc), optimizing their properties by blending both polymers is expected to address the shortage. The enhanced polymeric blend membrane (EPBM) was developed by varying the composition of PVAc ranging from 5 to 20 wt. % with 95 to 80 wt. % base PSU in dimethyl- acetamide (DMAc) solvent. The DEA amine composition was added to the blend and kept at 10 wt. % over solvent. The tensile analysis technique is utilized to evaluate the mechanical behaviour of a polymeric material which comprises the deformation of the polymeric material underneath the effect of an applied force prior to failure. The mechanical analysis showed improvement in tensile strength, Young's modulus and elongation at break properties with the increase in PVAc/DEA composition in the enhanced polymeric blend membranes. The elongation at break property increased with an increase in the amine contents which indicated the flexibility of the EPBM. In addition, the mechanical analysis revealed remarkable enhancement in the mechanical properties of the EPBM which might be attributed to the robust interactions among the PSU blend with PVAc and DEA.
{"title":"Effect of Mechanical Properties in Enhanced Polymeric Blend Membranes","authors":"A. Mushtaq, H. Mukhtar, A. Shariff","doi":"10.52763/PJSIR.PHYS.SCI.64.2.2021.97.102","DOIUrl":"https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.97.102","url":null,"abstract":"This study was carried out to evaluate the effect of blending the rubbery and glassy polymer with an alkanolamine on the mechanical properties. Due to the intrinsic properties of glassy polysulfone (PSU) and rubbery polyvinyl acetate (PVAc), optimizing their properties by blending both polymers is expected to address the shortage. The enhanced polymeric blend membrane (EPBM) was developed by varying the composition of PVAc ranging from 5 to 20 wt. % with 95 to 80 wt. % base PSU in dimethyl- acetamide (DMAc) solvent. The DEA amine composition was added to the blend and kept at 10 wt. % over solvent. The tensile analysis technique is utilized to evaluate the mechanical behaviour of a polymeric material which comprises the deformation of the polymeric material underneath the effect of an applied force prior to failure. The mechanical analysis showed improvement in tensile strength, Young's modulus and elongation at break properties with the increase in PVAc/DEA composition in the enhanced polymeric blend membranes. The elongation at break property increased with an increase in the amine contents which indicated the flexibility of the EPBM. In addition, the mechanical analysis revealed remarkable enhancement in the mechanical properties of the EPBM which might be attributed to the robust interactions among the PSU blend with PVAc and DEA.","PeriodicalId":19924,"journal":{"name":"Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90893412","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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