The genus Pholidota has good medicinal value,and is often over-excavated by humans.Coupled with its low natural reproduction rate,Pholidota is almost endangered.This paper summarized the tissue culture and rapid propa...The genus Pholidota has good medicinal value,and is often over-excavated by humans.Coupled with its low natural reproduction rate,Pholidota is almost endangered.This paper summarized the tissue culture and rapid propagation technology of Pholidota in recent years,aiming to provide key technical support for resource protection and development of Pholidota and preliminary foundation and technical support for follow-up related research.展开更多
It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient ...It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient technology system,this test used stem with buds of 16 cultivars and super lines including Yali,Jingbaili,03-04-034,03-08-080 and so on as materials to study the best way for explant sampling time and position,sterilization time using HgCl 2 and hormone concentrations.The result indicated that the optimum technology system was that the middle parts of longest shoots before 20 d after full-blossom were sterilized for 8 min by 0.1%HgCl 2 and inoculated on the development medium MS+6-BA 0.5 mg/L+IBA 0.2 mg/L+saccharose 3%+agar 0.6%(pH=5.8),and then trans-inoculated into propagation medium MS+6-BA 1.0 mg/L+IBA 0.3 mg/L+saccharose 3%+agar 0.6%(pH=5.8).展开更多
There are abundant tight sandstone gas resources in the Sichuan Basin,which are the important objects of reserve and production increase and large-scale development.Due to their discontinuous sandbody distribution,nar...There are abundant tight sandstone gas resources in the Sichuan Basin,which are the important objects of reserve and production increase and large-scale development.Due to their discontinuous sandbody distribution,narrow channels,and strong horizontal and vertical heteroge-neity,however,conventional fracturing technologies cannot achieve the ideal stimulation effect here.In order to address this difficulty,this paper dissects the geology engineering characteristics of tight sandstone gas reservoirs in the western Sichuan Basin.Starting from the seepage mechanics theory,the concept of“multi-scale high-density”tight gas fracturing technology is put forward by fully referring to the experience of previous multi-round reservoir stimulation in the western Sichuan Basin and the idea of unconventional volume fracturing technology.In addition,its conceptual connotation,key technologies and implementation effects are illustrated.The following research results are obtained.First,the seepage characteristics make it necessary for the efficient production of tight gas reserves to increase fracture density and stimulated reservoir volume(SRV).Second,the“multi-scale high-density”fracturing technology emphasizes the rationality of high-density hydraulic fracture creation and the matching of multi-scale fractureflow capacity,and aims at establishing a multi-level fracture system with effective and steady gasflow in tight reservoirs through fracturing.Third,the“wide,dense,support,stable,and precise”fracturing technology is applied to improve single well production and estimated ultimate recovery(EUR).Fourth,the engineering practice of“multi-scale high-density”fracturing technology in the tight reservoirs of Jurassic Shaximiao Formation and Triassic Xujiahe Formation in the ZJ Gas Field realizes the average single well production rate of 15.6104 m3/d,which is 1.96 times higher than that before the stimulation.Obviously,it provides powerful support for the operation of the ZJ Gas Field into a giant gasfield with the reserves of 100 billion cubic meters.In conclusion,the formation of the concept and key technologies of“multi-scale high-density”fracturing technology effectively supports the efficient development of tight gas in the western Sichuan Basin and points out the following research direction of tight gas reservoir stimulation.The research results provide reference and guidance for the large-scale benefit development of tight gas in China.展开更多
Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of...Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation payload.Presently,BDS can provide basic services globally,and its augmentation system is also being tested.This paper gives an overview of BDS and satellite navigation augmentation technologies.This overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment technologies.In each part,these technologies are described from the perspectives of preliminary information,research progress,and summary.Moreover,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation system.Furthermore,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research.展开更多
基金Supported by The Basic Ability Improvement Project of Young and Middle-aged Teachers in Guangxi Universities(2019KY0349)Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicines(GKJZ[2014]32)+3 种基金Collaborative Innovation Center of Zhuang and Yao Ethnic Medicines(GKKY[2013]20)Ethnic Medicine Resources and Application Engineering Research Center of Guangxi Zhuang Autonomous Region(GFGGJH[2020]2605)"The Eighth Batch of Guangxi Specially-employed Expert Projects"(GRCTZ[2019]13)Youth Fund Project of Guangxi University of Traditional Chinese Medicine(2019QN012).
文摘The genus Pholidota has good medicinal value,and is often over-excavated by humans.Coupled with its low natural reproduction rate,Pholidota is almost endangered.This paper summarized the tissue culture and rapid propagation technology of Pholidota in recent years,aiming to provide key technical support for resource protection and development of Pholidota and preliminary foundation and technical support for follow-up related research.
基金Supported by Projects from Hebei Natural Science Fund Committee(C2018301032)Hebei Support Project(16226312D-3)Innovation Team Project of Hebei Academy of Agriculture and Forest(C19R0601-2).
文摘It is the most available way to obtain self-rooted seedlings by tissue culture,which could breed de-virus seedlings with uniform traits and contribute to improve seedling quality.To construct a complete and efficient technology system,this test used stem with buds of 16 cultivars and super lines including Yali,Jingbaili,03-04-034,03-08-080 and so on as materials to study the best way for explant sampling time and position,sterilization time using HgCl 2 and hormone concentrations.The result indicated that the optimum technology system was that the middle parts of longest shoots before 20 d after full-blossom were sterilized for 8 min by 0.1%HgCl 2 and inoculated on the development medium MS+6-BA 0.5 mg/L+IBA 0.2 mg/L+saccharose 3%+agar 0.6%(pH=5.8),and then trans-inoculated into propagation medium MS+6-BA 1.0 mg/L+IBA 0.3 mg/L+saccharose 3%+agar 0.6%(pH=5.8).
基金supported by the key project of the United Foun-dation of National NaturalScience Foundation of China“Basic Research on Volumetric Acid Fracturing of Deep Sulfur-bearing Carbonate Gas Reservoirs in Sichuan Basin”(No.U21A20105)CNPC Science and Technology Innovation Project"Research on the Mechanism of Complex Fracture Propagation and Control Measures of Temporary Plugging Fracturing of Shale Gas Reservoir"(No.2020D-5007-0208).
文摘There are abundant tight sandstone gas resources in the Sichuan Basin,which are the important objects of reserve and production increase and large-scale development.Due to their discontinuous sandbody distribution,narrow channels,and strong horizontal and vertical heteroge-neity,however,conventional fracturing technologies cannot achieve the ideal stimulation effect here.In order to address this difficulty,this paper dissects the geology engineering characteristics of tight sandstone gas reservoirs in the western Sichuan Basin.Starting from the seepage mechanics theory,the concept of“multi-scale high-density”tight gas fracturing technology is put forward by fully referring to the experience of previous multi-round reservoir stimulation in the western Sichuan Basin and the idea of unconventional volume fracturing technology.In addition,its conceptual connotation,key technologies and implementation effects are illustrated.The following research results are obtained.First,the seepage characteristics make it necessary for the efficient production of tight gas reserves to increase fracture density and stimulated reservoir volume(SRV).Second,the“multi-scale high-density”fracturing technology emphasizes the rationality of high-density hydraulic fracture creation and the matching of multi-scale fractureflow capacity,and aims at establishing a multi-level fracture system with effective and steady gasflow in tight reservoirs through fracturing.Third,the“wide,dense,support,stable,and precise”fracturing technology is applied to improve single well production and estimated ultimate recovery(EUR).Fourth,the engineering practice of“multi-scale high-density”fracturing technology in the tight reservoirs of Jurassic Shaximiao Formation and Triassic Xujiahe Formation in the ZJ Gas Field realizes the average single well production rate of 15.6104 m3/d,which is 1.96 times higher than that before the stimulation.Obviously,it provides powerful support for the operation of the ZJ Gas Field into a giant gasfield with the reserves of 100 billion cubic meters.In conclusion,the formation of the concept and key technologies of“multi-scale high-density”fracturing technology effectively supports the efficient development of tight gas in the western Sichuan Basin and points out the following research direction of tight gas reservoir stimulation.The research results provide reference and guidance for the large-scale benefit development of tight gas in China.
基金the National Natural Science Foundation of China(No.61571309)Talent Project of Revitalization Liaoning(No.XLYC1907022)+1 种基金Natural Science Foundation of Liaoning Province(No.2019-MS-251)High-Level Innovation Talent Project of Shenyang(No.RC190030).
文摘Several noteworthy breakthroughs have been made with the BeiDou Navigation Satellite System(BDS)and other global navigation satellite systems as well as the associated augmentation systems,such as the commissioning of the BDS-3 preliminary system and the successful launch of the first BDS-3 GEO satellite which carries the satellite-based augmentation payload.Presently,BDS can provide basic services globally,and its augmentation system is also being tested.This paper gives an overview of BDS and satellite navigation augmentation technologies.This overview is divided into four parts,which include the system segment technologies,satellite segment technologies,propagation segment technologies,and user segment technologies.In each part,these technologies are described from the perspectives of preliminary information,research progress,and summary.Moreover,the significance and progress of the BeiDou Satellite-based Augmentation System(BDSBAS),low earth orbit augmentation,and the national BeiDou ground-based augmentation system are presented,along with the airborne-based augmentation system.Furthermore,the conclusions and discussions covering popular topics for research,frontiers in research and development,achievements,and suggestions are listed for future research.
