Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by 2050.Hydrogen is ...Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by 2050.Hydrogen is considered to be the most potential clean energy in this century under the background of carbon neutrality.At present,the industrial methods for producing hydrogen are mainly by steam-hydrocarbon(such as coal and natural gas)reforming and by electrolysis of water,while the exploration and development of natural hydrogen had just started.According to this literature review:(1)Natural hydrogen can be divided into three categories,including free hydrogen,hydrogen in inclusions and dissolved hydrogen;(2)natural hydrogen could be mainly from abiotic origins such as by deep-seated hydrogen generation,water-rock reaction or water radiolysis;(3)natural hydrogen is widely distributed and presents great potential,and the potential natural hydrogen sources excluding deep source of hydrogen is about(254±91)×10^(9) m^(3)/a according to a latest estimate;(4)at present,natural hydrogen has been mined in Mali,and the exploration and development of natural hydrogen has also been carried out in Australia,Brazil,the United States and some European countries,to find many favorable areas and test some technical methods for natural hydrogen exploration.Natural hydrogen is expected to be an important part of hydrogen energy production in the future energy pattern.Based on a thorough literature review,this study introduced the origin,classification,and global discovery of natural hydrogen,as well as summarized the current global status and discussed the possibility of natural hydrogen exploration and development,aiming to provide reference for the future natural hydrogen exploration and development.展开更多
Editor’s words The author puts forward some problems involving in CIETAC Arbitration Rules 2000 such as the third nation- ality of the presiding arbitrator, the full autonomy of the parties to choose Arbitration Rule...Editor’s words The author puts forward some problems involving in CIETAC Arbitration Rules 2000 such as the third nation- ality of the presiding arbitrator, the full autonomy of the parties to choose Arbitration Rules and the improvement of applying for interim measures and so on, which are welcomed by CIETAC, though some of which CIETAC does do that in practice, for instance, appointing the third nationalities as presiding arbitrator, and some of which the improvement shall be followed by the law, for instance, the problem of interim measures. We hope there are more articles contributed to arbitration in China directly deal with the theory and practice of arbitration in China as well as all over the world.展开更多
Through detailed analyses of the distribution characteristics of organic-rich shale, appearance features of high-quality shale, microscopic characteristics of shale reservoir rocks, fracability, and the relationship b...Through detailed analyses of the distribution characteristics of organic-rich shale, appearance features of high-quality shale, microscopic characteristics of shale reservoir rocks, fracability, and the relationship between preservation conditions and shale gas enrichment in Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in Sichuan Basin, theoretical understandings and specific suggestions with respect to the exploration and development of shale gas in China are summarized and proposed respectively. Important geological understandings in the exploration and development of shale gas of the Wufeng Formation–Longmaxi Formation in the Sichuan Basin can be summarized into the following aspects: depositional environment and depositional process control the distribution of organic-rich shale; high quality shale in "sweet spot segments" are commonly characterized by high content of organic carbon, high brittleness, high porosity and gas content; organic pores are important storage space for the enrichment of shale gas; preservation conditions are the key factor for the geological evaluation of shale gas in structurally complex regions; shale gas can be considered as "artificial gas reservoirs" and the fracability assessment is essential for high-production; nanoscale storage space and the mode of occurrence control the special seepage characteristics of shale gas. The following suggestions are proposed for the development of China's shale gas industry:(1) focus more on fundamental research to achieve new breakthrough in the geological theory of shale gas;(2) emphasize exploration practices to have all-round discoveries in multiple strata;(3) study the regularities of development and production to establish new models of shale gas development;(4) think creatively to invent new technologies to tackle key problems;(5) explore the management innovation to create new mechanisms in shale gas development.展开更多
The Kinetica-I rocket is designed for small-and medium-sized spacecraft launch missions to sun-synchronous orbit and low Earth orbit.The maiden flight was performed on July 27,2022.The Kinetica-I rocket is characteriz...The Kinetica-I rocket is designed for small-and medium-sized spacecraft launch missions to sun-synchronous orbit and low Earth orbit.The maiden flight was performed on July 27,2022.The Kinetica-I rocket is characterized by competitive payload capability and cost,robust orbital insertion accuracy,high reliability,availability at short notice and logistical versatility.12 new core technologies have been achieved during the development of the rocket.It is of great significance in promoting the innovation of China's solid carrier rocket technology and science exploration.展开更多
Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total int...Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total internal reflection from a dielectric interface or a photonic band gap in a periodic system, these photonic structures do not rely on conventional metal-coated mirrors to confine light in small volumes, which have brought forth new developments in both classical and quantum optics. This focus issue showcases several such developments and related findings, which may pave the way for the next generation of on-chip photonic devices based on microcavities.展开更多
基金funded by the projects initiated by the China Geological Survey(DD20221794 and DD20190414).
文摘Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by 2050.Hydrogen is considered to be the most potential clean energy in this century under the background of carbon neutrality.At present,the industrial methods for producing hydrogen are mainly by steam-hydrocarbon(such as coal and natural gas)reforming and by electrolysis of water,while the exploration and development of natural hydrogen had just started.According to this literature review:(1)Natural hydrogen can be divided into three categories,including free hydrogen,hydrogen in inclusions and dissolved hydrogen;(2)natural hydrogen could be mainly from abiotic origins such as by deep-seated hydrogen generation,water-rock reaction or water radiolysis;(3)natural hydrogen is widely distributed and presents great potential,and the potential natural hydrogen sources excluding deep source of hydrogen is about(254±91)×10^(9) m^(3)/a according to a latest estimate;(4)at present,natural hydrogen has been mined in Mali,and the exploration and development of natural hydrogen has also been carried out in Australia,Brazil,the United States and some European countries,to find many favorable areas and test some technical methods for natural hydrogen exploration.Natural hydrogen is expected to be an important part of hydrogen energy production in the future energy pattern.Based on a thorough literature review,this study introduced the origin,classification,and global discovery of natural hydrogen,as well as summarized the current global status and discussed the possibility of natural hydrogen exploration and development,aiming to provide reference for the future natural hydrogen exploration and development.
文摘Editor’s words The author puts forward some problems involving in CIETAC Arbitration Rules 2000 such as the third nation- ality of the presiding arbitrator, the full autonomy of the parties to choose Arbitration Rules and the improvement of applying for interim measures and so on, which are welcomed by CIETAC, though some of which CIETAC does do that in practice, for instance, appointing the third nationalities as presiding arbitrator, and some of which the improvement shall be followed by the law, for instance, the problem of interim measures. We hope there are more articles contributed to arbitration in China directly deal with the theory and practice of arbitration in China as well as all over the world.
基金Supported by the Chinese Academy of Engineering Consultancy Project(2018-xz-09-01)
文摘Through detailed analyses of the distribution characteristics of organic-rich shale, appearance features of high-quality shale, microscopic characteristics of shale reservoir rocks, fracability, and the relationship between preservation conditions and shale gas enrichment in Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in Sichuan Basin, theoretical understandings and specific suggestions with respect to the exploration and development of shale gas in China are summarized and proposed respectively. Important geological understandings in the exploration and development of shale gas of the Wufeng Formation–Longmaxi Formation in the Sichuan Basin can be summarized into the following aspects: depositional environment and depositional process control the distribution of organic-rich shale; high quality shale in "sweet spot segments" are commonly characterized by high content of organic carbon, high brittleness, high porosity and gas content; organic pores are important storage space for the enrichment of shale gas; preservation conditions are the key factor for the geological evaluation of shale gas in structurally complex regions; shale gas can be considered as "artificial gas reservoirs" and the fracability assessment is essential for high-production; nanoscale storage space and the mode of occurrence control the special seepage characteristics of shale gas. The following suggestions are proposed for the development of China's shale gas industry:(1) focus more on fundamental research to achieve new breakthrough in the geological theory of shale gas;(2) emphasize exploration practices to have all-round discoveries in multiple strata;(3) study the regularities of development and production to establish new models of shale gas development;(4) think creatively to invent new technologies to tackle key problems;(5) explore the management innovation to create new mechanisms in shale gas development.
文摘The Kinetica-I rocket is designed for small-and medium-sized spacecraft launch missions to sun-synchronous orbit and low Earth orbit.The maiden flight was performed on July 27,2022.The Kinetica-I rocket is characterized by competitive payload capability and cost,robust orbital insertion accuracy,high reliability,availability at short notice and logistical versatility.12 new core technologies have been achieved during the development of the rocket.It is of great significance in promoting the innovation of China's solid carrier rocket technology and science exploration.
文摘Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total internal reflection from a dielectric interface or a photonic band gap in a periodic system, these photonic structures do not rely on conventional metal-coated mirrors to confine light in small volumes, which have brought forth new developments in both classical and quantum optics. This focus issue showcases several such developments and related findings, which may pave the way for the next generation of on-chip photonic devices based on microcavities.