In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two t...In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel.展开更多
In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,Si...In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,SiC containing brick B,mullite-andalusite brick,spinel containing brick,zirconia containing brick,corundum-mullite brick and grade B mullite brick,were analyzed in properties. It is found that the cooling zone lining adopting SiC containing bricks or mullite-andalusite bricks has much longer service life. Based on this,a new type of wear resistant brick was developed. The brick has a compressive strength of 135 MPa,a wear loss of 2. 10cm^3（only a quarter of that of the grade B mullite brick）,and a higher bulk density than the grade B mullite brick. The application of the brick in a 140t·h^（-1）coke dry quenching oven showed that it performed better than the grade B mullite brick. The cooling zone adopting the new bricks has a lower coke discharging temperature,which is beneficial to the enhancement of heat recovery efficiency and steam power generation.展开更多
Concrete dam construction, reservoir impoundment and operation are a complicated and long-term process. During the course of this process dam suffers lots of factors including changing temperature, humidity, deformati...Concrete dam construction, reservoir impoundment and operation are a complicated and long-term process. During the course of this process dam suffers lots of factors including changing temperature, humidity, deformation, loads and restraints around dam. With time going by, damage to darn concrete happens. As a result, the strength, stiffness and resistance of concrete will decrease accompanying with damage accumulation and dam structure performance behavior and lifetime will be shorten or even destructed. At present, most of researches focus on concrete material itself and seldom consider effects of water content for concrete structures. That is apparently inconsistent with the actual situation. In engineering practice, it is urgently needed to assess existing dam structure damage state considering dry zoning in concrete. Through taking C30 dam concrete as standard specimen, alternate freezing and thawing tests are undertaken and changing law of time-dependent concrete damage state resulting in alternate wetting and drying has been studied in this paper. And then calculation formulas of time-dependent concrete damage evolution process considering alternate wetting and drying under condition of freeze-thaw cycle tests are established. Combining with four parameters Hsieh-Ting-Chen （ H -T-C ） model, some relevant factors or parameters are obtained through indoor testing and life prediction model of concrete dam based on dry zoning and damage theory is put forward which provides technical supports for dam safety evaluation and management of sustainable development.展开更多
This article describes the development of human potential interaction between society and nature. The environment, sustainable use of natural resources, prevention of adverse effects of human activities on the environ...This article describes the development of human potential interaction between society and nature. The environment, sustainable use of natural resources, prevention of adverse effects of human activities on the environment, and disturbances of dynamical ecological balance of the existing natural systems have received increased attention. The heed is introduced both on the state scale and in broad circles of science and society in The Azerbaijan Republic.展开更多
Field studies were carried out during kharif 2016 and summer 2017 at Udyanagiri,UHS,Bagalkot,Karnataka,India to evaluate IPM modules against fruit fly in an already established guava orchard of variety Sardar(L-49).Am...Field studies were carried out during kharif 2016 and summer 2017 at Udyanagiri,UHS,Bagalkot,Karnataka,India to evaluate IPM modules against fruit fly in an already established guava orchard of variety Sardar(L-49).Among four modules,the mean fruit damage was significantly the lowest in M3(0.68%)followed by M2(1.19%)and M1(2.21%)and were on par with each other during kharif 2016.During summer 2017,M3 recorded significantly lowest damage(0.59%)followed by M2(0.92%)and M1(2.41%)but were on with each other.The highest per cent protection was afforded by M3(95.76 and 96.76,respectively)during 2016 and 2017.The average fruit yield over the years of experimentation revealed significantly the highest fruit yield(8.13 t/ha)from M3 followed by M2(7.32 t/ha)and M1(5.31 t/ha).Among the four modules,highest B:C was from M3(7.65)followed by M2(6.67)and M1(4.91).展开更多
Cutaneous Leishmaniasis (CL) is a severe health problem and a parasitic disease on human dermal and widely pervades tropical and subtropical developing counties. The study is mainly focused on Geographic Information S...Cutaneous Leishmaniasis (CL) is a severe health problem and a parasitic disease on human dermal and widely pervades tropical and subtropical developing counties. The study is mainly focused on Geographic Information System (GIS) based Situational Analysis (SA). The clinically recorded 394 CL patients’ information was obtained from the District General Hospital of Polonnaruwa (DGHP) for 2017 and 2018. The spatial distribution of these patients was collected using Global Positing System (GPS). Moran’s I Index spatial autocorrelation technique and Getis-Ord Gi were used to identify the study site’s hot spot and cold spot areas. More than 75% of the CL patients’ population were highly involved with agricultural activities, and they are the highly exposed group of the CL in the study area. Also, 75% of the CL population were men, and the highly vulnerable age group was 35 - 39 men and 40 - 44 women. The generated Moran’s I Index indicates 0.0321, representing a randomly distributed pattern of CL patients over the District, and the Getis-Ord Gi Z Score value was >1.96 (p < 0.05). It is revealed that, during and in the post-harvesting periods of paddy cultivation, farmers are highly exposed to sandflies becoming CL patients. Due to this situation, the researchers observed that the highest number of patients have reported in May of both years and the infection period is two to four weeks earlier than the reported month. Hence to prevent the disease spread, it is essential to implement an awareness program regarding sandflies’ behaviour and CLD.展开更多
The presence of stress is shown to have a significant impact on chloride ions in concrete. Reinforced concrete is usually durable and cost-effective which has resulted in its widespread use for construction, however, ...The presence of stress is shown to have a significant impact on chloride ions in concrete. Reinforced concrete is usually durable and cost-effective which has resulted in its widespread use for construction, however, the concrete subjected to environment and load has become increasingly apparently that attacked by aggressive agents such as chloride ion. In this study, the coupling influences are stress effects and environmental problems on the coastline concrete durability have been investigated. A series of cyclic of a wet-dry cycle and submersion tests were performed onto the stressed concrete to obtain an understanding of the physical mechanisms causing the accumulation of chlorides in the interior pores of concrete under different stress types and exposure environments, based on the same duration. Specimens were prepared and subjected to NaCl solution in a wet-dry cycle and submersion, the chloride in the tension zone is gradual with increasing the stress level, as well as the chloride ion in the wet-dry cycle, is increasing the number of cycles. The apparent diffusion coefficient of each specimen was calculated respectively, the profile of concentration at a different section of tension and compression zones were presented in influence factors of the number of cycles, the length of drying phase, and periodic wetting cycles with sodium solution was discussed. After employed Fick’s second law, the results suggested D<sub>a</sub> in a wet-dry cycle is much higher than the D<sub>a</sub> in submersion zones.展开更多
Water resources are subjected to ever-increasing supply constraints due to extensive agricultural water demand for irrigated lands.Therefore,water-saving irrigation strategies need to be explored.The present study was...Water resources are subjected to ever-increasing supply constraints due to extensive agricultural water demand for irrigated lands.Therefore,water-saving irrigation strategies need to be explored.The present study was conducted to explore the possibilities of using regulated deficit irrigation(RDI)and partial root zone drying irrigation(PRD)methods as water-saving irrigation techniques for subsurface irrigation.The objective of this study are to assess the effects of RDI and PRD irrigation on the water productivity of vegetable crops(tomato)under SSD systems in arid climatic conditions,and to compare the responses of tomato crops to PRD,RDI,and FI under an SSD system in terms of productivity,crop quality,and the amount of water saved.The field experiment was conducted during the fall 2014-2015 and 2015-2016 seasons in an experimental field located on an educational farm owned by the Faculty of Food and Agriculture Sciences Department,King Saud University,Riyadh,Kingdom of Saudi Arabia.An area of 102.7 m^(2)(13 m×7.9 m)was allocated for the experiment to manage three treatments:RDI,PRD,and full irrigation(FI).The RDI and PRD treatments received 70%of the irrigation water volume of FI.Each was replicated three times.The most important results indicated that the soil water content(SWC)for the RDI and PRD treatments was lower than that of the FI treatments.FI had the highest stomatal conductance values(gs),while PRD had the lowest stomatal conductance values.The photosynthetic rate(A_(n))was lower under RDI and PRD compared to FI.However,there was no significant change in A_(n) between treatments for most readings taken during both time periods,which means that the water saving treatments(PRD and RDI)did not affect the net photosynthesis rate,thereby enhancing irrigation water use efficiency(IWUE)under DI treatments.The water-saving irrigation techniques decreased transpiration rate(T)compared to the FI treatment.The values of the abscisic acid(ABA)contents were higher under PRD and RDI than FI.The marketable yield under the FI treatment yielded the highest values.The fruit quality parameter results showed that the RDI and PRD treatments increased the total soluble solids,vitamin C,and titratable acidity of tomato compared to the FI treatment.Most of the minimum IWUE values were associated with FI.These results indicate the effects of deficit levels on IWUE.展开更多
文摘In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel.
文摘In order to prolong the service life of the cooling zone of large scale coke dry quenching ovens,six kinds possible refractories for the cooling zone of large scale coke dry quenching ovens： SiC containing brick A,SiC containing brick B,mullite-andalusite brick,spinel containing brick,zirconia containing brick,corundum-mullite brick and grade B mullite brick,were analyzed in properties. It is found that the cooling zone lining adopting SiC containing bricks or mullite-andalusite bricks has much longer service life. Based on this,a new type of wear resistant brick was developed. The brick has a compressive strength of 135 MPa,a wear loss of 2. 10cm^3（only a quarter of that of the grade B mullite brick）,and a higher bulk density than the grade B mullite brick. The application of the brick in a 140t·h^（-1）coke dry quenching oven showed that it performed better than the grade B mullite brick. The cooling zone adopting the new bricks has a lower coke discharging temperature,which is beneficial to the enhancement of heat recovery efficiency and steam power generation.
基金This research was supported by NSFC （National Natural Science Foundation of China） （Granted No.： 50909054, 50925933）.
文摘Concrete dam construction, reservoir impoundment and operation are a complicated and long-term process. During the course of this process dam suffers lots of factors including changing temperature, humidity, deformation, loads and restraints around dam. With time going by, damage to darn concrete happens. As a result, the strength, stiffness and resistance of concrete will decrease accompanying with damage accumulation and dam structure performance behavior and lifetime will be shorten or even destructed. At present, most of researches focus on concrete material itself and seldom consider effects of water content for concrete structures. That is apparently inconsistent with the actual situation. In engineering practice, it is urgently needed to assess existing dam structure damage state considering dry zoning in concrete. Through taking C30 dam concrete as standard specimen, alternate freezing and thawing tests are undertaken and changing law of time-dependent concrete damage state resulting in alternate wetting and drying has been studied in this paper. And then calculation formulas of time-dependent concrete damage evolution process considering alternate wetting and drying under condition of freeze-thaw cycle tests are established. Combining with four parameters Hsieh-Ting-Chen （ H -T-C ） model, some relevant factors or parameters are obtained through indoor testing and life prediction model of concrete dam based on dry zoning and damage theory is put forward which provides technical supports for dam safety evaluation and management of sustainable development.
文摘This article describes the development of human potential interaction between society and nature. The environment, sustainable use of natural resources, prevention of adverse effects of human activities on the environment, and disturbances of dynamical ecological balance of the existing natural systems have received increased attention. The heed is introduced both on the state scale and in broad circles of science and society in The Azerbaijan Republic.
文摘Field studies were carried out during kharif 2016 and summer 2017 at Udyanagiri,UHS,Bagalkot,Karnataka,India to evaluate IPM modules against fruit fly in an already established guava orchard of variety Sardar(L-49).Among four modules,the mean fruit damage was significantly the lowest in M3(0.68%)followed by M2(1.19%)and M1(2.21%)and were on par with each other during kharif 2016.During summer 2017,M3 recorded significantly lowest damage(0.59%)followed by M2(0.92%)and M1(2.41%)but were on with each other.The highest per cent protection was afforded by M3(95.76 and 96.76,respectively)during 2016 and 2017.The average fruit yield over the years of experimentation revealed significantly the highest fruit yield(8.13 t/ha)from M3 followed by M2(7.32 t/ha)and M1(5.31 t/ha).Among the four modules,highest B:C was from M3(7.65)followed by M2(6.67)and M1(4.91).
文摘Cutaneous Leishmaniasis (CL) is a severe health problem and a parasitic disease on human dermal and widely pervades tropical and subtropical developing counties. The study is mainly focused on Geographic Information System (GIS) based Situational Analysis (SA). The clinically recorded 394 CL patients’ information was obtained from the District General Hospital of Polonnaruwa (DGHP) for 2017 and 2018. The spatial distribution of these patients was collected using Global Positing System (GPS). Moran’s I Index spatial autocorrelation technique and Getis-Ord Gi were used to identify the study site’s hot spot and cold spot areas. More than 75% of the CL patients’ population were highly involved with agricultural activities, and they are the highly exposed group of the CL in the study area. Also, 75% of the CL population were men, and the highly vulnerable age group was 35 - 39 men and 40 - 44 women. The generated Moran’s I Index indicates 0.0321, representing a randomly distributed pattern of CL patients over the District, and the Getis-Ord Gi Z Score value was >1.96 (p < 0.05). It is revealed that, during and in the post-harvesting periods of paddy cultivation, farmers are highly exposed to sandflies becoming CL patients. Due to this situation, the researchers observed that the highest number of patients have reported in May of both years and the infection period is two to four weeks earlier than the reported month. Hence to prevent the disease spread, it is essential to implement an awareness program regarding sandflies’ behaviour and CLD.
文摘The presence of stress is shown to have a significant impact on chloride ions in concrete. Reinforced concrete is usually durable and cost-effective which has resulted in its widespread use for construction, however, the concrete subjected to environment and load has become increasingly apparently that attacked by aggressive agents such as chloride ion. In this study, the coupling influences are stress effects and environmental problems on the coastline concrete durability have been investigated. A series of cyclic of a wet-dry cycle and submersion tests were performed onto the stressed concrete to obtain an understanding of the physical mechanisms causing the accumulation of chlorides in the interior pores of concrete under different stress types and exposure environments, based on the same duration. Specimens were prepared and subjected to NaCl solution in a wet-dry cycle and submersion, the chloride in the tension zone is gradual with increasing the stress level, as well as the chloride ion in the wet-dry cycle, is increasing the number of cycles. The apparent diffusion coefficient of each specimen was calculated respectively, the profile of concentration at a different section of tension and compression zones were presented in influence factors of the number of cycles, the length of drying phase, and periodic wetting cycles with sodium solution was discussed. After employed Fick’s second law, the results suggested D<sub>a</sub> in a wet-dry cycle is much higher than the D<sub>a</sub> in submersion zones.
基金This Project was funded by the National Plan for Science,Technology and Innovation(MAARIFAH),King Abdulaziz City for Science and Technology,Kingdom of Saudi Arabia,Award Number(11-WAT1978-02).
文摘Water resources are subjected to ever-increasing supply constraints due to extensive agricultural water demand for irrigated lands.Therefore,water-saving irrigation strategies need to be explored.The present study was conducted to explore the possibilities of using regulated deficit irrigation(RDI)and partial root zone drying irrigation(PRD)methods as water-saving irrigation techniques for subsurface irrigation.The objective of this study are to assess the effects of RDI and PRD irrigation on the water productivity of vegetable crops(tomato)under SSD systems in arid climatic conditions,and to compare the responses of tomato crops to PRD,RDI,and FI under an SSD system in terms of productivity,crop quality,and the amount of water saved.The field experiment was conducted during the fall 2014-2015 and 2015-2016 seasons in an experimental field located on an educational farm owned by the Faculty of Food and Agriculture Sciences Department,King Saud University,Riyadh,Kingdom of Saudi Arabia.An area of 102.7 m^(2)(13 m×7.9 m)was allocated for the experiment to manage three treatments:RDI,PRD,and full irrigation(FI).The RDI and PRD treatments received 70%of the irrigation water volume of FI.Each was replicated three times.The most important results indicated that the soil water content(SWC)for the RDI and PRD treatments was lower than that of the FI treatments.FI had the highest stomatal conductance values(gs),while PRD had the lowest stomatal conductance values.The photosynthetic rate(A_(n))was lower under RDI and PRD compared to FI.However,there was no significant change in A_(n) between treatments for most readings taken during both time periods,which means that the water saving treatments(PRD and RDI)did not affect the net photosynthesis rate,thereby enhancing irrigation water use efficiency(IWUE)under DI treatments.The water-saving irrigation techniques decreased transpiration rate(T)compared to the FI treatment.The values of the abscisic acid(ABA)contents were higher under PRD and RDI than FI.The marketable yield under the FI treatment yielded the highest values.The fruit quality parameter results showed that the RDI and PRD treatments increased the total soluble solids,vitamin C,and titratable acidity of tomato compared to the FI treatment.Most of the minimum IWUE values were associated with FI.These results indicate the effects of deficit levels on IWUE.
