Cultivating strong seedlings is an important guarantee for the production of high-quality flue-cured tobacco, while there are many disadvantages in tobacco floating system that is commonly adopted in China. To improve...Cultivating strong seedlings is an important guarantee for the production of high-quality flue-cured tobacco, while there are many disadvantages in tobacco floating system that is commonly adopted in China. To improve the tobacco floating system, with Xiangyan No.3 as experimental material, the effects of water control before transplanting and rooting powder treatment on tobacco seedling quality and physiological properties at green stage were investigated. The results showed that： （1） water control showed small influence on tobacco seedling quality, while rooting powder treatment and water control ＋ rooting powder treatment showed great influence on tobacco seedling quality, mainly represented by reduced plant height, thickened stem and increased dry matter accumulative amount; （2） water control before transplanting and rooting powder treatment all improved leaf chlorophyll content and root vigor of tobacco seedlings, and the effect of water control ＋ rooting powder treatment was best, followed by rooting powder treatment and water control; （3） all treatments increased the nitrate reductase and invertase activity, and reduced the MDA content of tobacco seedlings, and the effect of water control ＋ rooting powder treatment was best, followed by rooting powder treatment and water control. Mean- while, the treatment effect 10 d before the transplanting was better than that 5 d before the transplanting. In overall, the improvement effects of water control 10 d before transplanting ＋ rooting powder treatment on tobacco seedling quality and physiological properties at green stage were the best.展开更多
After the oilfield development enters the period of extra-high water cut, the permeability of the area near the well is reduced due to the erosion and dissolution of cement by water. At the same time, due to the frequ...After the oilfield development enters the period of extra-high water cut, the permeability of the area near the well is reduced due to the erosion and dissolution of cement by water. At the same time, due to the frequent production of layer adjustment, there is a phenomenon of multiple layers drilled in a well, which increases the construction difficulty. According to the difference of oil-water density, there is also a high water cut section in one interval, and there is a phenomenon that the oil-bearing section is in the upper part and the water-bearing section is in the lower part. According to the research results of "universal distribution and local enrichment" of the remaining oil in geological institute, the material basis of deep digging potential still exists in the high water cut rear stratified section. Guided by the concept of moderate sand control, through the analysis of oil well sand production, the application of remaining oil distribution, the research and application of water control and sand control technology in complex well conditions, and the research of moderate water control technology with complementary advantages, a set of technology suitable for combining sand control and water control in Gudao Oilfield has finally been formed. The application of this technology has achieved the purpose of simplifying downhole string and prolonging water control period.展开更多
Firstly,Jiang Shidu and his historical background were introduced.His water control practice and characteristics were analyzed in detail,such as drawing water to irrigate farmland,opening up waterways for grain transp...Firstly,Jiang Shidu and his historical background were introduced.His water control practice and characteristics were analyzed in detail,such as drawing water to irrigate farmland,opening up waterways for grain transportation by ship,guaranteeing the supply of fresh water to salt ponds,transforming drainage channels,establishing urban water supply system,and constructing military defense projects.展开更多
In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select...In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select timely and reasonable temperature control and crack prevention measures, this paper takes the upper lock head of the Datengxia Water Control Project as an example, and uses three-dimensional finite element method to simulate and recheck and calculate the temperature field and creep stress field according to the construction progress, latest material parameters and accurate boundary conditions. The analysis results show that the overall stress of the concrete at the upper gate head is not large after the temperature control measures formulated in this paper are adopted, which meets the requirements of concrete crack prevention, indicating that the temperature control measures formulated are appropriate.展开更多
Water disasters are common disasters in coal mine production. With the continuous increase of coal mining depth, the threat of coal mine water disasters has also increased. Coal mine water disasters will bring great l...Water disasters are common disasters in coal mine production. With the continuous increase of coal mining depth, the threat of coal mine water disasters has also increased. Coal mine water disasters will bring great losses to the mine, such as mechanical and electrical equipment rust or damage, if serious, it will lead to casualties. In most cases, the mine rescue work is very difficult after the occurrence of water disasters, and it is very difficult to drain water for a short time. Therefore, effective measures should be taken to do a good job of mine water prevention and control.展开更多
Aimed at the disadvantages of secondary damage to oil layers caused by the conventional bull-heading water control technique, a thermo-sensitive temporary plugging agent for water control was synthesized by water solu...Aimed at the disadvantages of secondary damage to oil layers caused by the conventional bull-heading water control technique, a thermo-sensitive temporary plugging agent for water control was synthesized by water solution polymerization and applied in the field with a new secondary temporary plugging technique. The optimization and performance evaluation of thermo-sensitive temporary plugging agent were carried out through laboratory experiments. The optimized formula is as follows:(6%-8%) acrylamide +(0.08%-0.12%) ammonium persulfate +(1.5%-2.0%) sepiolite +(0.5%-0.8%) polyethylene glycol diacrylate. The thermo-sensitive temporary plugging agent is suitable for formation temperatures of 70-90 ?C, it has high temporary plugging strength(5-40 k Pa), controllable degradation time(1-15 d), the apparent viscosity after degradation of less than 100 m Pa?S and the permeability recovery value of simulated cores of more than 95%. Based on the research results, secondary temporary plugging technique was used in a horizontal well in the Jidong Oilfield. After treatment, the well saw a drop of water cut to 27%, and now it has a water cut of 67%, its daily increased oil production was 4.8 t, and the cumulative oil increment was 750 t, demonstrating that the technique worked well in controlling water production and increasing oil production.展开更多
Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water...Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water control project of Poyang Lake,residents' interest protection system and ecological benefit safeguard system for eco-tourism compensation were put forward.展开更多
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r...Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.展开更多
Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water i...Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.展开更多
The development of gas condensate reservoirs with a large gas cap,thin oil rim,strong bottom water,and natural barriers faces numerous challenges,including reservoir heterogeneity,coning effects,phase changes,and mult...The development of gas condensate reservoirs with a large gas cap,thin oil rim,strong bottom water,and natural barriers faces numerous challenges,including reservoir heterogeneity,coning effects,phase changes,and multiphase flow dynamics.The influx of gas and water may lead to a low recovery of the oil rim,while reservoir heterogeneity and natural barriers further exacerbate the uneven distribution of reservoir fluid,complicating development strategies.This paper aims to investigate innovative and effective development strategies for this type of reservoir.A detailed,proportionally scaled numerical simulation is performed based on the experimental results of an artificial sand-filled model,providing novel insights into the dynamic behavior of these reservoirs.By understanding the phase behavior and fluid flow characteristics of the reservoir,the study simulates various strategies for the rational and efficient development of the gas condensate reservoir.These strategies include well patterns and completions,the decision to develop the oil rim or gas cap,depletion rates,the bottom water control,and gas injection.The results show that horizontal wells or highly deviated wells are more suitable for the development of the oil rim,as they provide larger control ranges.The presence of strong bottom water is advantageous for displacement energy supply and pressure maintenance,but it intensifies water coning effects,leading to an earlier breakthrough and a sharp production decline.Therefore,it is preferable to apply highly deviated wells at the oil-gas contact,developing the oil rim at lower rates and smaller pressure gradients,followed by developing the gas cap.This approach can reduce water coning effects and improve recovery,with oil and gas recovery reaching 24.4%and 67.95%,respectively,which is an increase of 16.74%and 17.84%compared to direct depletion development of the gas cap.Due to the strong water bottom,continuous gas injection at the top of the reservoir becomes challenging.This study introduces gas assisted gravity drainage with water control technology,a novel and highly effective approach that addresses the impact of bottom water coning effects on the oil and gas zones and overcomes the limitations of gas flooding in reservoirs with strong bottom water.This method can significantly improve oil and gas recovery,achieving recovery of 39.74%and 84.50%,respectively.Compared to the conventional depletion strategy of sequential oil rim and gas cap development,this method achieves additional improvements of 15.33%and 16.55%in oil and gas recovery,respectively.展开更多
Considering the danger of water inrush in mining very thick coal seam under water-rich roof in Majialiang Coal Mine,the universal discrete element(UDEC)software was used to simulate the overburden fracture evolution l...Considering the danger of water inrush in mining very thick coal seam under water-rich roof in Majialiang Coal Mine,the universal discrete element(UDEC)software was used to simulate the overburden fracture evolution laws when mining 4#coal seam.Besides,this study researched on the influence of face advancing length,speed and mining height on the height of the water flowing fractured zones(HWFFZ),and analyzed the correlation of face advancing length and change rules of aquifer water levels and goaf water inflow.Based on those mentioned above,this research proposed the following water-controlling technologies:draining the roof water before mining,draining goaf water,reasonable advancing speed and mining thickness.These water-controlling technologies were successfully used in the feld,thus ensured safely mining the very thick coal seam under water-rich roof.展开更多
The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip.The heat of a hot steel strip is mainly extracted by cooling water during runout.In order to ...The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip.The heat of a hot steel strip is mainly extracted by cooling water during runout.In order to study the heat transfer by water jet impingement boiling during runout,apilot facility was constructed at the University of British Columbia.On this pilot facility,the water jet impingement tests were carried out under various cooling conditions to investigate the effect of processing parameters,such as cooling water temperature,water jet impingement velocity,initial strip temperature,water flow rate,water nozzle diameter and array of water nozzles,on the heat transfer of heated strip.The results obtained contribute to the optimization of cooling water during runout.展开更多
The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake i...The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake is of great importance to the improvement of water environment in the valley and the eutrophication status in th lake. Firstly, the basic ideas, key taches and main methods for water pollution control of inflow rivers of Taihu Lake was put forward in this article, Basic on these theories, the pollutant source status in the comprehensive treatment zone of the 15 major inflow rivers was analysized, the countermeasures of pollution control and main regulation projects were introduced, and the total abatement of pollutants was predicted. With the implement of regulation projects, the number of rivers with water quality worse than Grade V among the 15 major inflow rivers had come from 9 to 3, and the eutrophication status of Taihu Lake had changed from medium level to light level. The overall treatment of the major inflow rivers of the Taihu Lake had achieved initial success.展开更多
Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced con...Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced conformance efficiency and affected de-velopment response.Therefore,the research on profile control and water shut-off agents becomes increasingly important for thermal recovery wells.The requirements on the performances of profile control and water shut-off agents are discussed in conjunction with the physical properties of heavy oil reservoirs and the technical conditions of steam injection in China.Based on the mechanism of action,research progress and application status,5 agents are summarized including polymer gel,solid particles plugging agent,foam,water-in-oil emulsion and salt precipitation.Problems in each agent are mentioned,and optimization solutions are put for-ward.At last,the development trend of future profile control and water shut-off agents is put forward,i.e.synthesizing agents of low cost and high-temperature resistance,intensifying mechanism research,developing composite system,and researching on new technologies that are less harmful and environmental friendly.展开更多
Caving of mine roofs from water inrush due to anomalous pressure is one of the major disasters and accidents that can occur in mines during production.Roof water inrush can trigger a wide range of roof collapse,causin...Caving of mine roofs from water inrush due to anomalous pressure is one of the major disasters and accidents that can occur in mines during production.Roof water inrush can trigger a wide range of roof collapse,causing major accidents from breaking roof supports while caving.These failures flood wells and do a great deal of damage to mines and endanger mine safety.Our objective is to analyze the anomalies of water inrush crushing the support at the #6301 working face in the Jisan Coal Mine of the Yanzhou Mining Group.Through information of water inrush to the roof,damage caused by tectonic movements,information on the damage caused by roof collapse and the theory about the distribution of pressure in mine abutments,we advice adjusting the length of the working face and the position of open-off cut relatively to the rich water area.In the case of anomalous roof pressure we should develop a state equation to estimate preventive measures with＂transferring rock beam＂theory.Simultaneously, we improve the capacity of drainage equipment and ensured adequate water retention at the storehouse. These are all major technologies to ensure the control and prevention against accidents caused by anomalous water inrush in roofs,thus ensuring safety in the production process of a coal mine.展开更多
Improper flow control devices in a multi-strand tundish can cause some problems, for example, liquid steel cannot reach every nozzle at the same time and the liquid steel in nozzles far away from the entry zone has a ...Improper flow control devices in a multi-strand tundish can cause some problems, for example, liquid steel cannot reach every nozzle at the same time and the liquid steel in nozzles far away from the entry zone has a lower temperature. The water model experiment of a six-strand tundish of Tianjin Iron ＆ Steel Co. Ltd. was performed, a new ＂U＂ type baffle was obtained, and its parameters were defined by perpendicular analysis. The ＂U＂ baffle can not only improve those imperfections, but also prolong the residence time of nonmetallic inclusions, which is good for their flotation and separation.展开更多
In this paper, by in-depth geological research of Kalamkas Oilfield in Central Asia, the geological body has been re-ascertained; combined with fine study of reservoir engineering, based on the understanding of the di...In this paper, by in-depth geological research of Kalamkas Oilfield in Central Asia, the geological body has been re-ascertained; combined with fine study of reservoir engineering, based on the understanding of the distribution of remaining oil horizontal wells have been given full play to stabilizing oil production and controlling water cut, reducing the producing pressure drop, improving well productivity and other advantages, and the development and deployment has been optimized; horizontal wells have been applied to solve problems such as old well casing damages, shutting down wells, low-productivity and low- efficiency wells, and high water cut wells to improve the utilization rate of old wells; through separate layer system improved injection production pattern, adjustment wells have been optimized and deployed, and part measures wells have been preferably selected to tap the residual oil improve the degree of reserves control realize the stabilization of oil production and control of water cut in an old oilfield, and further improve the development effects.展开更多
Nowadays, the fast development of nanobiotechnology, has led to rapid diagnosis of important infectious diseases such as arboviruses-borne diseases, vector-borne infections and waterborne parasites diseases and others...Nowadays, the fast development of nanobiotechnology, has led to rapid diagnosis of important infectious diseases such as arboviruses-borne diseases, vector-borne infections and waterborne parasites diseases and others in order to reduce and avoid further dissemination of the infections within the general population. Furthermore, new nanomedicines based on the application of silver and gold nanoparticles which are less toxic, more effective, and that does not generate resistance could help to solve the problems of parasitic disease like leishmaniasis and chagas disease. It turns out that the combination of nanoparticles with antibiotics not only reduces the toxicity of both agents towards human cells but also enhances their ability to destroy bacteria by facilitating the binding of antibiotics to the microbes. Moreover, combining nanoparticles with antimicrobial peptides and essential oils with nanoparticles generates genuine synergy against microbial resistance.展开更多
The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,...The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,as the intensity of anthropogenic activities in the region has continued to increase,the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered.In this study,water samples from the western,southern,and northeastern border areas of the Qinghai-Tibet Plateau,where human activities are ongoing,were collected,analyzed,and measured.The regional differences and factors controlling them were also investigated.The key results were obtained as follows.(1) Differences in the physical properties and hydrochemical characteristics,and their controlling factors,occurred in the different boundary areas of the Qinghai-Tibet Plateau.These differences were mainly the consequence of the geographical environment and geological conditions.(2) The water quality was good and suitable for drinking,with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards.(3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks,with the former the most influential.(4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards.展开更多
基金Supported by Science and Technology Plan Project of Hunan Province(2013NK3036)Science and Technology Projects of Changsha Tobacco Company(12218,12231)~~
文摘Cultivating strong seedlings is an important guarantee for the production of high-quality flue-cured tobacco, while there are many disadvantages in tobacco floating system that is commonly adopted in China. To improve the tobacco floating system, with Xiangyan No.3 as experimental material, the effects of water control before transplanting and rooting powder treatment on tobacco seedling quality and physiological properties at green stage were investigated. The results showed that： （1） water control showed small influence on tobacco seedling quality, while rooting powder treatment and water control ＋ rooting powder treatment showed great influence on tobacco seedling quality, mainly represented by reduced plant height, thickened stem and increased dry matter accumulative amount; （2） water control before transplanting and rooting powder treatment all improved leaf chlorophyll content and root vigor of tobacco seedlings, and the effect of water control ＋ rooting powder treatment was best, followed by rooting powder treatment and water control; （3） all treatments increased the nitrate reductase and invertase activity, and reduced the MDA content of tobacco seedlings, and the effect of water control ＋ rooting powder treatment was best, followed by rooting powder treatment and water control. Mean- while, the treatment effect 10 d before the transplanting was better than that 5 d before the transplanting. In overall, the improvement effects of water control 10 d before transplanting ＋ rooting powder treatment on tobacco seedling quality and physiological properties at green stage were the best.
文摘After the oilfield development enters the period of extra-high water cut, the permeability of the area near the well is reduced due to the erosion and dissolution of cement by water. At the same time, due to the frequent production of layer adjustment, there is a phenomenon of multiple layers drilled in a well, which increases the construction difficulty. According to the difference of oil-water density, there is also a high water cut section in one interval, and there is a phenomenon that the oil-bearing section is in the upper part and the water-bearing section is in the lower part. According to the research results of "universal distribution and local enrichment" of the remaining oil in geological institute, the material basis of deep digging potential still exists in the high water cut rear stratified section. Guided by the concept of moderate sand control, through the analysis of oil well sand production, the application of remaining oil distribution, the research and application of water control and sand control technology in complex well conditions, and the research of moderate water control technology with complementary advantages, a set of technology suitable for combining sand control and water control in Gudao Oilfield has finally been formed. The application of this technology has achieved the purpose of simplifying downhole string and prolonging water control period.
文摘Firstly,Jiang Shidu and his historical background were introduced.His water control practice and characteristics were analyzed in detail,such as drawing water to irrigate farmland,opening up waterways for grain transportation by ship,guaranteeing the supply of fresh water to salt ponds,transforming drainage channels,establishing urban water supply system,and constructing military defense projects.
文摘In the process of construction and operation, large volume concrete structures often generate large temperature stress, which in turn leads to cracks. Before the construction of concrete structures, in order to select timely and reasonable temperature control and crack prevention measures, this paper takes the upper lock head of the Datengxia Water Control Project as an example, and uses three-dimensional finite element method to simulate and recheck and calculate the temperature field and creep stress field according to the construction progress, latest material parameters and accurate boundary conditions. The analysis results show that the overall stress of the concrete at the upper gate head is not large after the temperature control measures formulated in this paper are adopted, which meets the requirements of concrete crack prevention, indicating that the temperature control measures formulated are appropriate.
文摘Water disasters are common disasters in coal mine production. With the continuous increase of coal mining depth, the threat of coal mine water disasters has also increased. Coal mine water disasters will bring great losses to the mine, such as mechanical and electrical equipment rust or damage, if serious, it will lead to casualties. In most cases, the mine rescue work is very difficult after the occurrence of water disasters, and it is very difficult to drain water for a short time. Therefore, effective measures should be taken to do a good job of mine water prevention and control.
基金Supported by the National Key Special Science and Technology Project(2016ZX05015-002)PetroChina Key Special Science and Technology Project(2016E-0104)
文摘Aimed at the disadvantages of secondary damage to oil layers caused by the conventional bull-heading water control technique, a thermo-sensitive temporary plugging agent for water control was synthesized by water solution polymerization and applied in the field with a new secondary temporary plugging technique. The optimization and performance evaluation of thermo-sensitive temporary plugging agent were carried out through laboratory experiments. The optimized formula is as follows:(6%-8%) acrylamide +(0.08%-0.12%) ammonium persulfate +(1.5%-2.0%) sepiolite +(0.5%-0.8%) polyethylene glycol diacrylate. The thermo-sensitive temporary plugging agent is suitable for formation temperatures of 70-90 ?C, it has high temporary plugging strength(5-40 k Pa), controllable degradation time(1-15 d), the apparent viscosity after degradation of less than 100 m Pa?S and the permeability recovery value of simulated cores of more than 95%. Based on the research results, secondary temporary plugging technique was used in a horizontal well in the Jidong Oilfield. After treatment, the well saw a drop of water cut to 27%, and now it has a water cut of 67%, its daily increased oil production was 4.8 t, and the cumulative oil increment was 750 t, demonstrating that the technique worked well in controlling water production and increasing oil production.
基金Supported by Key Bid Program of Poyang Lake Ecological Economy Research Center of Jiangxi Province(09KJ01)~~
文摘Through analysis on the background to develop eco-tourism and necessity for ecological compensation,based on specific condition of Hukou County,in line with the situation to develop eco-tourism during ecological water control project of Poyang Lake,residents' interest protection system and ecological benefit safeguard system for eco-tourism compensation were put forward.
文摘Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.
基金supported by the National Natural Sciences Foundation of China(No.51309216)the Ministry of Sciences and Technology of the People’s Republic of China(No.2012ZX07408-002)
文摘Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.
基金the support from the National Natural Science Foundation of China(NSFC Grant No.:52004032)。
文摘The development of gas condensate reservoirs with a large gas cap,thin oil rim,strong bottom water,and natural barriers faces numerous challenges,including reservoir heterogeneity,coning effects,phase changes,and multiphase flow dynamics.The influx of gas and water may lead to a low recovery of the oil rim,while reservoir heterogeneity and natural barriers further exacerbate the uneven distribution of reservoir fluid,complicating development strategies.This paper aims to investigate innovative and effective development strategies for this type of reservoir.A detailed,proportionally scaled numerical simulation is performed based on the experimental results of an artificial sand-filled model,providing novel insights into the dynamic behavior of these reservoirs.By understanding the phase behavior and fluid flow characteristics of the reservoir,the study simulates various strategies for the rational and efficient development of the gas condensate reservoir.These strategies include well patterns and completions,the decision to develop the oil rim or gas cap,depletion rates,the bottom water control,and gas injection.The results show that horizontal wells or highly deviated wells are more suitable for the development of the oil rim,as they provide larger control ranges.The presence of strong bottom water is advantageous for displacement energy supply and pressure maintenance,but it intensifies water coning effects,leading to an earlier breakthrough and a sharp production decline.Therefore,it is preferable to apply highly deviated wells at the oil-gas contact,developing the oil rim at lower rates and smaller pressure gradients,followed by developing the gas cap.This approach can reduce water coning effects and improve recovery,with oil and gas recovery reaching 24.4%and 67.95%,respectively,which is an increase of 16.74%and 17.84%compared to direct depletion development of the gas cap.Due to the strong water bottom,continuous gas injection at the top of the reservoir becomes challenging.This study introduces gas assisted gravity drainage with water control technology,a novel and highly effective approach that addresses the impact of bottom water coning effects on the oil and gas zones and overcomes the limitations of gas flooding in reservoirs with strong bottom water.This method can significantly improve oil and gas recovery,achieving recovery of 39.74%and 84.50%,respectively.Compared to the conventional depletion strategy of sequential oil rim and gas cap development,this method achieves additional improvements of 15.33%and 16.55%in oil and gas recovery,respectively.
基金provided by the Priority Academic Program Development of Jiangsu Higher Education Institutions of China(No.SZBF2011-6-B35)the Fundamental Research Funds for the Central Universities of China(No.2012LWB42)
文摘Considering the danger of water inrush in mining very thick coal seam under water-rich roof in Majialiang Coal Mine,the universal discrete element(UDEC)software was used to simulate the overburden fracture evolution laws when mining 4#coal seam.Besides,this study researched on the influence of face advancing length,speed and mining height on the height of the water flowing fractured zones(HWFFZ),and analyzed the correlation of face advancing length and change rules of aquifer water levels and goaf water inflow.Based on those mentioned above,this research proposed the following water-controlling technologies:draining the roof water before mining,draining goaf water,reasonable advancing speed and mining thickness.These water-controlling technologies were successfully used in the feld,thus ensured safely mining the very thick coal seam under water-rich roof.
文摘The controlled runout table cooling is essential in determining the final mechanical properties and flatness of steel strip.The heat of a hot steel strip is mainly extracted by cooling water during runout.In order to study the heat transfer by water jet impingement boiling during runout,apilot facility was constructed at the University of British Columbia.On this pilot facility,the water jet impingement tests were carried out under various cooling conditions to investigate the effect of processing parameters,such as cooling water temperature,water jet impingement velocity,initial strip temperature,water flow rate,water nozzle diameter and array of water nozzles,on the heat transfer of heated strip.The results obtained contribute to the optimization of cooling water during runout.
文摘The pollutants from the 15 rivers inflowing into Lake Taihu accounted for about 80% of the total amount of the pollutants inflowing into Lake Taihu. Therefore, overall treatment of the inflowing rivers of Taihu Lake is of great importance to the improvement of water environment in the valley and the eutrophication status in th lake. Firstly, the basic ideas, key taches and main methods for water pollution control of inflow rivers of Taihu Lake was put forward in this article, Basic on these theories, the pollutant source status in the comprehensive treatment zone of the 15 major inflow rivers was analysized, the countermeasures of pollution control and main regulation projects were introduced, and the total abatement of pollutants was predicted. With the implement of regulation projects, the number of rivers with water quality worse than Grade V among the 15 major inflow rivers had come from 9 to 3, and the eutrophication status of Taihu Lake had changed from medium level to light level. The overall treatment of the major inflow rivers of the Taihu Lake had achieved initial success.
文摘Heavy oil will play an important role in future resources exploitation.Factors such as reservoir heterogeneity and adverse oil/steam mobility ratio have led to severe steam channeling and fingering,thereby reduced conformance efficiency and affected de-velopment response.Therefore,the research on profile control and water shut-off agents becomes increasingly important for thermal recovery wells.The requirements on the performances of profile control and water shut-off agents are discussed in conjunction with the physical properties of heavy oil reservoirs and the technical conditions of steam injection in China.Based on the mechanism of action,research progress and application status,5 agents are summarized including polymer gel,solid particles plugging agent,foam,water-in-oil emulsion and salt precipitation.Problems in each agent are mentioned,and optimization solutions are put for-ward.At last,the development trend of future profile control and water shut-off agents is put forward,i.e.synthesizing agents of low cost and high-temperature resistance,intensifying mechanism research,developing composite system,and researching on new technologies that are less harmful and environmental friendly.
基金sponsored by the National Natural Science Foundation of China(No.50874021 )the Program for New Century Excellent Talents in University(No.NCET-08-0833)the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT0656) of the Ministry of Education of China.
文摘Caving of mine roofs from water inrush due to anomalous pressure is one of the major disasters and accidents that can occur in mines during production.Roof water inrush can trigger a wide range of roof collapse,causing major accidents from breaking roof supports while caving.These failures flood wells and do a great deal of damage to mines and endanger mine safety.Our objective is to analyze the anomalies of water inrush crushing the support at the #6301 working face in the Jisan Coal Mine of the Yanzhou Mining Group.Through information of water inrush to the roof,damage caused by tectonic movements,information on the damage caused by roof collapse and the theory about the distribution of pressure in mine abutments,we advice adjusting the length of the working face and the position of open-off cut relatively to the rich water area.In the case of anomalous roof pressure we should develop a state equation to estimate preventive measures with＂transferring rock beam＂theory.Simultaneously, we improve the capacity of drainage equipment and ensured adequate water retention at the storehouse. These are all major technologies to ensure the control and prevention against accidents caused by anomalous water inrush in roofs,thus ensuring safety in the production process of a coal mine.
文摘Improper flow control devices in a multi-strand tundish can cause some problems, for example, liquid steel cannot reach every nozzle at the same time and the liquid steel in nozzles far away from the entry zone has a lower temperature. The water model experiment of a six-strand tundish of Tianjin Iron ＆ Steel Co. Ltd. was performed, a new ＂U＂ type baffle was obtained, and its parameters were defined by perpendicular analysis. The ＂U＂ baffle can not only improve those imperfections, but also prolong the residence time of nonmetallic inclusions, which is good for their flotation and separation.
文摘In this paper, by in-depth geological research of Kalamkas Oilfield in Central Asia, the geological body has been re-ascertained; combined with fine study of reservoir engineering, based on the understanding of the distribution of remaining oil horizontal wells have been given full play to stabilizing oil production and controlling water cut, reducing the producing pressure drop, improving well productivity and other advantages, and the development and deployment has been optimized; horizontal wells have been applied to solve problems such as old well casing damages, shutting down wells, low-productivity and low- efficiency wells, and high water cut wells to improve the utilization rate of old wells; through separate layer system improved injection production pattern, adjustment wells have been optimized and deployed, and part measures wells have been preferably selected to tap the residual oil improve the degree of reserves control realize the stabilization of oil production and control of water cut in an old oilfield, and further improve the development effects.
文摘Nowadays, the fast development of nanobiotechnology, has led to rapid diagnosis of important infectious diseases such as arboviruses-borne diseases, vector-borne infections and waterborne parasites diseases and others in order to reduce and avoid further dissemination of the infections within the general population. Furthermore, new nanomedicines based on the application of silver and gold nanoparticles which are less toxic, more effective, and that does not generate resistance could help to solve the problems of parasitic disease like leishmaniasis and chagas disease. It turns out that the combination of nanoparticles with antibiotics not only reduces the toxicity of both agents towards human cells but also enhances their ability to destroy bacteria by facilitating the binding of antibiotics to the microbes. Moreover, combining nanoparticles with antimicrobial peptides and essential oils with nanoparticles generates genuine synergy against microbial resistance.
基金Key R&D and Transformation Program of Tibet,No.XZ201901NB08Major Science and Technology Project of Tibet,No.XZ201901NA03,No.XZ201801NA02
文摘The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,as the intensity of anthropogenic activities in the region has continued to increase,the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered.In this study,water samples from the western,southern,and northeastern border areas of the Qinghai-Tibet Plateau,where human activities are ongoing,were collected,analyzed,and measured.The regional differences and factors controlling them were also investigated.The key results were obtained as follows.(1) Differences in the physical properties and hydrochemical characteristics,and their controlling factors,occurred in the different boundary areas of the Qinghai-Tibet Plateau.These differences were mainly the consequence of the geographical environment and geological conditions.(2) The water quality was good and suitable for drinking,with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards.(3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks,with the former the most influential.(4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards.
