It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in...It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in transporting hot water through solar energy. The combination of the two methods resolved the issue of heat preservation difficulty and guaranteed growth of strawberry in winter.展开更多
In order to study the hydrocarbon generation(HCGE)characteristics of coal-bearing basins,the coal-measure source rocks of the Middle Jurassic-Lower Jurassic(MLJ)of the piedmont thrust belt in the southern margin of th...In order to study the hydrocarbon generation(HCGE)characteristics of coal-bearing basins,the coal-measure source rocks of the Middle Jurassic-Lower Jurassic(MLJ)of the piedmont thrust belt in the southern margin of the Junggar Basin in Northwest China are taken as research objects.More than 60 MLJ samples were collected from outcrops and wells.Total organic carbon(TOC),rock pyrolysis(Rock-Eval),organic petrological,vitrinite reflectance(%Ro),and hydrous pyrolysis were performed to analyze the relevant samples.The pyrolysis gases and liquid products were measured,and then the chemical composition,as well as carbon isotopes of the gases,were analyzed.The results indicate that the MLJ source rocks have the capacity for large-scale gas generation.In addition,for coal-measure source rocks,the heavier the carbon isotope of kerogen(δ^(13)C_(kerogen)),the lower the liquid hydrocarbon and hydrocarbon gas yield,and the easier it is to produce non-hydrocarbon gas.It is worth noting that when theδ^(13)C_(kerogen)in organic matter(OM)is relatively heavier,the fractionation of its products may become weaker in the evolutionary process.The vital contribution of the MLJ source rock to natural gas resources in the study area was further confirmed by comparing it with the Jurassic source gas.展开更多
Not only being abundant in resources, natural gas also helps power grids consume wind energy, solar energy and etc. The promotion of natu ral gas is an essential zoay to facilitate the development of nezo energy and c...Not only being abundant in resources, natural gas also helps power grids consume wind energy, solar energy and etc. The promotion of natu ral gas is an essential zoay to facilitate the development of nezo energy and complete the transition to an energy system where the renewable energy is dominant. The operation of energy Internet with a concept of equal, open, cooperative and sharing, and the optimization of a combined energy of gas, electricity, heating and cooling, could significantly improve the energy efficiency. Meanwhile, the development of energy lnternet technology will subvert the existing division of energy industry, and generate new commercial formats with features of highly openness. It will also subvert some existing market rules, change the governance methods, generate renovations in organizations, business models and government management methods, thus requires further revolution in energy industry. In order to promote the rapid and healthy development of ＂lnternet plus＂ natural gas industry, a series of policies and precautions are needed to be inhvduced and improved.展开更多
Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays ene...Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays energy chemistry is becoming one of the hot topics, and many excellent research papers in the field of energy chemistry are emerging in different scientific iournals.展开更多
Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays ene...Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays energy chemistry is becoming one of the hot topics, and many excellent research papers in the field of energy chemistry are emerging in different scientific journals. To extensively report the most important and latest developments in energy chemistry, we are going to rename the Journal of Natural Gas Chemistry as the Journal of Energy Chemistry starting from January 2013. The main contents of the Journal of Energy Chemistry will include new developments in fields of optimized chemical utilization of both conventional and unconventional fossil energies; research and utilization of hydrogen energy; conversion and storage of electrochemical energy; capturing, storage and chemical utilization of CO2; new materials and nanotechnologies related to energy utilization; chemical conversion of biomasses; and chemical approaches related to photo-catalysis, and so on.展开更多
With the vigorous promotion of energy conservation and implementation of clean energy strategies,China＇s natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important...With the vigorous promotion of energy conservation and implementation of clean energy strategies,China＇s natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important role in China＇s energy structure.This paper uses a Generalized Weng model to forecast Chinese regional natural gas production,where accuracy and reasonableness compared with other predictions are enhanced by taking remaining estimated recoverable resources as a criterion.The forecast shows that China＇s natural gas production will maintain a rapid growth with peak gas of 323 billion cubic meters a year coming in 2036;in 2020,natural gas production will surpass that of oil to become a more important source of energy.Natural gas will play an important role in optimizing China＇s energy consumption structure and will be a strategic replacement of oil.This will require that exploration and development of conventional natural gas is highly valued and its industrial development to be reasonably planned.As well,full use should be made of domestic and international markets.Initiative should also be taken in the exploration and development of unconventional and deepwater gas,which shall form a complement to the development of China＇s conventional natural gas industry.展开更多
The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estimate their severiti...The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estimate their severities, requiring only the information about the changes of a few lower natural frequencies. First, a damage quantification method is formulated and iterative approach is adopted for determining the damage extent. Then a damage localization algorithm is proposed, in which a damage indicator is formulated where unity value corresponds to the true damage scenario. Finally, numerical studies and model tests are conducted to demonstrate the effectiveness of the developed algorithm.展开更多
The measurement principle and analysis method of natural gamma-ray spectra using Nal(T1) scintillation spectrometer are briefly described first, thed block diagrams of the HD-8004 Nal(T1) gamma-ray spectrometer. Fina...The measurement principle and analysis method of natural gamma-ray spectra using Nal(T1) scintillation spectrometer are briefly described first, thed block diagrams of the HD-8004 Nal(T1) gamma-ray spectrometer. Finally, sample measurements are listed and discussed. The results are quite promising. Based on the analysis of these measurements, measures to improve the accuracy of spectrum measurement are proposed. It is well hoped that these measures call contribute to the development and application of gamma-ray spectrum measurement.展开更多
A hydroelectric power generator, which is able to extract the water flow energy from the hydroelastic response of an elastically supported rectangular wing, is experimentally investigated. An electric motor is used to...A hydroelectric power generator, which is able to extract the water flow energy from the hydroelastic response of an elastically supported rectangular wing, is experimentally investigated. An electric motor is used to excite pitching oscillations of the wing. Both the wing and the electric motor are supported by leaf springs which are designed to work both as a linear guide for the sway oscillations and as elastic elements. The wing mass in sway direction necessary to achieve a hydroelastic response is obtained by utilizing a mechanical snubber mechanism. The appropriate load to generate electricity is provided by magnetic dampers. In the previous paper, the generating power rate and the efficiency were examined through the experiments with a single wing model, and the feasibility of the flapping wing hydroelectric power generator was verified. In this paper, the influence of the neighboring wings is examined by using two experimental apparatuses, with the intention of achieving a practical cascade wing generator. Tests revealed that the cascade moving in-phase with the neighboring wings at narrower intervals has a higher rate of electric power generation.展开更多
The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconve...The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconventional oil production in the USA accounted for 41%of the total oil production;and unconventional natural gas production in China accounted for 35%of total gas production,showing strong growth momentum of unconventional hydrocarbons explorations.Unconventional hydrocarbons generally coexist with conventional petroleum resources;they sometimes distribute in a separate system,not coexisting with a conventional system.Identification and prediction of unconventional resources and their potentials are prominent challenges for geologists.This study analyzed the results of 12,237 drilling wells in six representative petroliferous basins in China and studied the correlations and differences between conventional and unconventional hydrocarbons by comparing their geological features.Migration and accumulation of conventional hydrocarbon are caused dominantly by buoyance.Wepropose a concept of buoyance-driven hydrocarbon accumulation depth to describe the deepest hydrocarbon accumulation depth driven dominantly by buoyance;beyond this depth the buoyance becomes unimportant for hydrocarbon accumulation.We found that the buoyance-driven hydrocarbon accumulation depth in petroliferous basins controls the different oil/gas reservoirs distribution and resource potentials.Hydrocarbon migration and accumulations above this depth is dominated by buoyancy,forming conventional reservoirs in traps with high porosity and permeability,while hydrocarbon migration and accumulation below this depth is dominated by non-buoyancy forces(mainly refers to capillary force,hydrocarbon volumeexpansion force,etc.),forming unconventional reservoirs in tight layers.The buoyance-driven hydrocarbon accumulation depths in six basins in China range from 1200mto 4200 m,which become shallowerwith increasing geothermal gradient,decreasing particle size of sandstone reservoir layers,or an uplift in the whole petroliferous basin.The predicted unconventional resource potential belowthe buoyance-driven hydrocarbon accumulation depth in six basins in China is more than 15.71×10^(9) t oil equivalent,among them 4.71×10^(9) t reserves have been proved.Worldwide,94%of 52,926 oil and gas reservoirs in 1186 basins are conventional reservoirs and only 6%of them are unconventional reservoirs.These 94%conventional reservoirs show promising exploration prospects in the deep area below buoyance-driven hydrocarbon accumulation depth.展开更多
Liquefied natural gas （LNG）, an increasingly widely applied clean fuel, releases a large number of cold energy in its regasification process. In the present paper, the existing power generation cycles utilizing LNG ...Liquefied natural gas （LNG）, an increasingly widely applied clean fuel, releases a large number of cold energy in its regasification process. In the present paper, the existing power generation cycles utilizing LNG cold energy are introduced and summarized. The direction of cycle improvement can be divided into the key factors affecting basic power generation cycles and the structural enhancement of cycles utilizing LNG cold energy. The former includes the effects of LNG-side parameters, working fluids, and inlet and outlet thermodynamic parameters of equipment, while the latter is based on Rankine cycle, Brayton cycle, Kalina cycle and their compound cycles. In the present paper, the diversities of cryogenic power generation cycles utilizing LNG cold energy are discussed and analyzed. It is pointed out that further researches should focus on the selection and component matching of organic mixed working fluids and the combination of process simulation and experi- mental investigation, etc.展开更多
Development of simple methods for preparation of polymeric electrode materials with nanofibrous network structure is a perspective way toward cheap supercapacitors with high specific capacitance and energy density. In...Development of simple methods for preparation of polymeric electrode materials with nanofibrous network structure is a perspective way toward cheap supercapacitors with high specific capacitance and energy density. In this work one-pot synthesis of electroactive ternary composite based on polypyrrole, polyacrylamide and chitin nanofibers with beneficial morphology was elaborated. Ternary system demonstrates better electrochemical performance in comparison with both polypyrrole–polyacrylamide and polypyrrole–chitin binary composites. Possible mechanism of synergistic effect of simultaneous influence of polyacrylamide and chitin nanofibers on the formation of composite＇s structure is discussed.The highest attained specific capacitance of electroactive polypyrrole in ternary composite reached 249 F/g at 0.5 A/g and 150 F/g at 32 A/g. Symmetrical supercapacitor was assembled using the elaborated electrode material. High specific capacitance 89 F/g and good cycling stability with capacitance retention of 90% after 3000 cycles at 2 A/g were measured.展开更多
In order to improve the performance of the Wells turbine for wave energy conversion, the effect of end plates on the turbine characteristics has been investigated experimentally by model testing under steady flow cond...In order to improve the performance of the Wells turbine for wave energy conversion, the effect of end plates on the turbine characteristics has been investigated experimentally by model testing under steady flow conditions. The end plate attached to the tip of the original rotor blade is slightly larger than the original blade profile. The characteristics of the Wells turbine with end plates have been compared with those of the original Wells turbine, i.e., the turbine without end plate. As a result, it has been concluded that the characteristics of the Wells turbine with end plates are superior to those of the original Wells turbine and the characteristics are dependent on the size and position of end plate. Furthermore, the effect of annular plate on the turbine performance, which encircles the turbine and is attached to the tip, was investigated as an additional experiment. However, its device was not effective in improving the turbine characteristics.展开更多
基金Supported by Zhenjiang Science&Technology Pillar Program(NY2013001)~~
文摘It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in transporting hot water through solar energy. The combination of the two methods resolved the issue of heat preservation difficulty and guaranteed growth of strawberry in winter.
基金financially supported by Xinjiang Oilfield Company of China(Grant No.2020-C4006)。
文摘In order to study the hydrocarbon generation(HCGE)characteristics of coal-bearing basins,the coal-measure source rocks of the Middle Jurassic-Lower Jurassic(MLJ)of the piedmont thrust belt in the southern margin of the Junggar Basin in Northwest China are taken as research objects.More than 60 MLJ samples were collected from outcrops and wells.Total organic carbon(TOC),rock pyrolysis(Rock-Eval),organic petrological,vitrinite reflectance(%Ro),and hydrous pyrolysis were performed to analyze the relevant samples.The pyrolysis gases and liquid products were measured,and then the chemical composition,as well as carbon isotopes of the gases,were analyzed.The results indicate that the MLJ source rocks have the capacity for large-scale gas generation.In addition,for coal-measure source rocks,the heavier the carbon isotope of kerogen(δ^(13)C_(kerogen)),the lower the liquid hydrocarbon and hydrocarbon gas yield,and the easier it is to produce non-hydrocarbon gas.It is worth noting that when theδ^(13)C_(kerogen)in organic matter(OM)is relatively heavier,the fractionation of its products may become weaker in the evolutionary process.The vital contribution of the MLJ source rock to natural gas resources in the study area was further confirmed by comparing it with the Jurassic source gas.
文摘Not only being abundant in resources, natural gas also helps power grids consume wind energy, solar energy and etc. The promotion of natu ral gas is an essential zoay to facilitate the development of nezo energy and complete the transition to an energy system where the renewable energy is dominant. The operation of energy Internet with a concept of equal, open, cooperative and sharing, and the optimization of a combined energy of gas, electricity, heating and cooling, could significantly improve the energy efficiency. Meanwhile, the development of energy lnternet technology will subvert the existing division of energy industry, and generate new commercial formats with features of highly openness. It will also subvert some existing market rules, change the governance methods, generate renovations in organizations, business models and government management methods, thus requires further revolution in energy industry. In order to promote the rapid and healthy development of ＂lnternet plus＂ natural gas industry, a series of policies and precautions are needed to be inhvduced and improved.
文摘Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays energy chemistry is becoming one of the hot topics, and many excellent research papers in the field of energy chemistry are emerging in different scientific iournals.
文摘Over the past decade, the Journal of Natural Gas Chemistry has become more and more international and has received large numbers of manuscripts concerning energy chemistry from all over the word. In deed, nowadays energy chemistry is becoming one of the hot topics, and many excellent research papers in the field of energy chemistry are emerging in different scientific journals. To extensively report the most important and latest developments in energy chemistry, we are going to rename the Journal of Natural Gas Chemistry as the Journal of Energy Chemistry starting from January 2013. The main contents of the Journal of Energy Chemistry will include new developments in fields of optimized chemical utilization of both conventional and unconventional fossil energies; research and utilization of hydrogen energy; conversion and storage of electrochemical energy; capturing, storage and chemical utilization of CO2; new materials and nanotechnologies related to energy utilization; chemical conversion of biomasses; and chemical approaches related to photo-catalysis, and so on.
基金the National Social Science Funds of China (13&ZD159)the National Natural Science Foundation of China (71303258, 71373285)+1 种基金MOE (Ministry of Education in China) Project of Humanities and Social Sciences (13YJC630148)Science Foundation of China University of Petroleum, Beijing (ZX20150130) for sponsoring this joint research
文摘With the vigorous promotion of energy conservation and implementation of clean energy strategies,China＇s natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important role in China＇s energy structure.This paper uses a Generalized Weng model to forecast Chinese regional natural gas production,where accuracy and reasonableness compared with other predictions are enhanced by taking remaining estimated recoverable resources as a criterion.The forecast shows that China＇s natural gas production will maintain a rapid growth with peak gas of 323 billion cubic meters a year coming in 2036;in 2020,natural gas production will surpass that of oil to become a more important source of energy.Natural gas will play an important role in optimizing China＇s energy consumption structure and will be a strategic replacement of oil.This will require that exploration and development of conventional natural gas is highly valued and its industrial development to be reasonably planned.As well,full use should be made of domestic and international markets.Initiative should also be taken in the exploration and development of unconventional and deepwater gas,which shall form a complement to the development of China＇s conventional natural gas industry.
基金supported by the National Natural Science Foundation of China (50909088, 51010009)Science & Technology Development Project of Qingdao (09-1-3-18-jch)Program for New Century Excellent Talents in University (NCET-10-0762)
文摘The present paper develops a new method for damage localization and severity estimation based on the employment of modal strain energy. This method is able to determine the damage locations and estimate their severities, requiring only the information about the changes of a few lower natural frequencies. First, a damage quantification method is formulated and iterative approach is adopted for determining the damage extent. Then a damage localization algorithm is proposed, in which a damage indicator is formulated where unity value corresponds to the true damage scenario. Finally, numerical studies and model tests are conducted to demonstrate the effectiveness of the developed algorithm.
文摘The measurement principle and analysis method of natural gamma-ray spectra using Nal(T1) scintillation spectrometer are briefly described first, thed block diagrams of the HD-8004 Nal(T1) gamma-ray spectrometer. Finally, sample measurements are listed and discussed. The results are quite promising. Based on the analysis of these measurements, measures to improve the accuracy of spectrum measurement are proposed. It is well hoped that these measures call contribute to the development and application of gamma-ray spectrum measurement.
文摘A hydroelectric power generator, which is able to extract the water flow energy from the hydroelastic response of an elastically supported rectangular wing, is experimentally investigated. An electric motor is used to excite pitching oscillations of the wing. Both the wing and the electric motor are supported by leaf springs which are designed to work both as a linear guide for the sway oscillations and as elastic elements. The wing mass in sway direction necessary to achieve a hydroelastic response is obtained by utilizing a mechanical snubber mechanism. The appropriate load to generate electricity is provided by magnetic dampers. In the previous paper, the generating power rate and the efficiency were examined through the experiments with a single wing model, and the feasibility of the flapping wing hydroelectric power generator was verified. In this paper, the influence of the neighboring wings is examined by using two experimental apparatuses, with the intention of achieving a practical cascade wing generator. Tests revealed that the cascade moving in-phase with the neighboring wings at narrower intervals has a higher rate of electric power generation.
基金by the National Natural Science Foundation of China(No.U19B6003-02)the National Basic Research Program(973)of China(No.2011CB201100).
文摘The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconventional oil production in the USA accounted for 41%of the total oil production;and unconventional natural gas production in China accounted for 35%of total gas production,showing strong growth momentum of unconventional hydrocarbons explorations.Unconventional hydrocarbons generally coexist with conventional petroleum resources;they sometimes distribute in a separate system,not coexisting with a conventional system.Identification and prediction of unconventional resources and their potentials are prominent challenges for geologists.This study analyzed the results of 12,237 drilling wells in six representative petroliferous basins in China and studied the correlations and differences between conventional and unconventional hydrocarbons by comparing their geological features.Migration and accumulation of conventional hydrocarbon are caused dominantly by buoyance.Wepropose a concept of buoyance-driven hydrocarbon accumulation depth to describe the deepest hydrocarbon accumulation depth driven dominantly by buoyance;beyond this depth the buoyance becomes unimportant for hydrocarbon accumulation.We found that the buoyance-driven hydrocarbon accumulation depth in petroliferous basins controls the different oil/gas reservoirs distribution and resource potentials.Hydrocarbon migration and accumulations above this depth is dominated by buoyancy,forming conventional reservoirs in traps with high porosity and permeability,while hydrocarbon migration and accumulation below this depth is dominated by non-buoyancy forces(mainly refers to capillary force,hydrocarbon volumeexpansion force,etc.),forming unconventional reservoirs in tight layers.The buoyance-driven hydrocarbon accumulation depths in six basins in China range from 1200mto 4200 m,which become shallowerwith increasing geothermal gradient,decreasing particle size of sandstone reservoir layers,or an uplift in the whole petroliferous basin.The predicted unconventional resource potential belowthe buoyance-driven hydrocarbon accumulation depth in six basins in China is more than 15.71×10^(9) t oil equivalent,among them 4.71×10^(9) t reserves have been proved.Worldwide,94%of 52,926 oil and gas reservoirs in 1186 basins are conventional reservoirs and only 6%of them are unconventional reservoirs.These 94%conventional reservoirs show promising exploration prospects in the deep area below buoyance-driven hydrocarbon accumulation depth.
文摘Liquefied natural gas （LNG）, an increasingly widely applied clean fuel, releases a large number of cold energy in its regasification process. In the present paper, the existing power generation cycles utilizing LNG cold energy are introduced and summarized. The direction of cycle improvement can be divided into the key factors affecting basic power generation cycles and the structural enhancement of cycles utilizing LNG cold energy. The former includes the effects of LNG-side parameters, working fluids, and inlet and outlet thermodynamic parameters of equipment, while the latter is based on Rankine cycle, Brayton cycle, Kalina cycle and their compound cycles. In the present paper, the diversities of cryogenic power generation cycles utilizing LNG cold energy are discussed and analyzed. It is pointed out that further researches should focus on the selection and component matching of organic mixed working fluids and the combination of process simulation and experi- mental investigation, etc.
基金supported by Russian Foundation(grant 16-13-10164)financial support of Russian Ministry of Education within State Contract 14.W03.31.0014(megagrant)
文摘Development of simple methods for preparation of polymeric electrode materials with nanofibrous network structure is a perspective way toward cheap supercapacitors with high specific capacitance and energy density. In this work one-pot synthesis of electroactive ternary composite based on polypyrrole, polyacrylamide and chitin nanofibers with beneficial morphology was elaborated. Ternary system demonstrates better electrochemical performance in comparison with both polypyrrole–polyacrylamide and polypyrrole–chitin binary composites. Possible mechanism of synergistic effect of simultaneous influence of polyacrylamide and chitin nanofibers on the formation of composite＇s structure is discussed.The highest attained specific capacitance of electroactive polypyrrole in ternary composite reached 249 F/g at 0.5 A/g and 150 F/g at 32 A/g. Symmetrical supercapacitor was assembled using the elaborated electrode material. High specific capacitance 89 F/g and good cycling stability with capacitance retention of 90% after 3000 cycles at 2 A/g were measured.
文摘In order to improve the performance of the Wells turbine for wave energy conversion, the effect of end plates on the turbine characteristics has been investigated experimentally by model testing under steady flow conditions. The end plate attached to the tip of the original rotor blade is slightly larger than the original blade profile. The characteristics of the Wells turbine with end plates have been compared with those of the original Wells turbine, i.e., the turbine without end plate. As a result, it has been concluded that the characteristics of the Wells turbine with end plates are superior to those of the original Wells turbine and the characteristics are dependent on the size and position of end plate. Furthermore, the effect of annular plate on the turbine performance, which encircles the turbine and is attached to the tip, was investigated as an additional experiment. However, its device was not effective in improving the turbine characteristics.
