The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geo...The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.展开更多
A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichno...A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnoge- nus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (in- cluding hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux pos- teriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much lar- ger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.展开更多
The inexhaustible heat deposit in great depths （5-10 km） is a scientific fact. Such deposit occurs around the globe. Thereby, everybody is enabled to generate autonomously clean and renewable energy, ample electrici...The inexhaustible heat deposit in great depths （5-10 km） is a scientific fact. Such deposit occurs around the globe. Thereby, everybody is enabled to generate autonomously clean and renewable energy, ample electricity and heat. The economical exploration and exploitation of this superdeep geothermal heat deposit requires a novel drilling technique, because the currently only deep drilling method （Rotary） is limited to about 5 km, due to the rising costs, depending exponentially on depth. Electro-pulse-boring （EPB） is a valuable option to Rotary drilling. EPB, originally investigated in Russia, is ready to be developed for industrialization. The feasibility of EPB is proven by many boreholes drilled up to 200 m in granite （crystalline）. Estimates show outstanding low costs for drilling by EPB： 100 E/m for a borehole with a large diameter （φ） such as 20 （50 cm）, independent on depth and applicable likewise for sediments and crystalline rocks, such as granite. The current rate of penetration （ROP） of 3 m per hour is planned to be augmented up to 35 m per hour, and again, irrespective whether in sedimentary or crystalline formations. Consequently, a 10 km deep borehole with φ 50 cm will ultimately be drilled within 12 days. EPB will create new markets, such as： （i） EPB shallow drilling for geotechnics, energy piles, measures in order to mitigate natural hazards, etc., （ii） EPB deep drilling （3-5 km） for hydro-geothermics, exploration campaigns etc. and （iii） EPB super-deep drilling （5-10 km） for petro-geothermies, enabling the economic generation of electricity. The autonomous and unlimited supply with cost efficient electricity, besides ample heat, ensures reliably clean and renew- able energy, thus, high supply security. Such development will provide a substantial relief to cope with the global challenge to limit the climate change below 2 ℃. The diminution of fossil fuels, due to the energy transition in order to mitigate the climate change, implies likewise the decrease of air pollution.展开更多
Based on microstructure analysis,diffusion theory,and hot deformation experiments,the solidification microstructure and element segregation of the Alloy 625 Plus ingot,the diffusion kinetics of Ti,Nb,and Mo during hom...Based on microstructure analysis,diffusion theory,and hot deformation experiments,the solidification microstructure and element segregation of the Alloy 625 Plus ingot,the diffusion kinetics of Ti,Nb,and Mo during homogenization and the hot deformation behavior of the homogenized ingot were investigated in this study.The results indicate that:(1)the solidified ingot exhibits a typical dendritic microstructure,and significant element segregation occurs,leading to the presence of Ti,Nb,and Mo-rich precipitates in the interdendritic region;(2)Following homogenization,the degree of element segregation in the ingot is significantly reduced.The diffusion coefficients(D)of Ti,Nb,and Mo under various homogenization conditions were calculated.Subsequently,the diffusion constants(D_(0))and activation energies(Q)of Ti,Nb,and Mo were obtained to be 0.01432,0.00397 and 0.00195 cm^(2)/s and 244.851,230.312,and 222.125 kJ/mol,respectively.Finally,the diffusion kinetics formulas for Ti,Nb,and Mo in Alloy 625 Plus were established.After homogenization at 1220℃for 8 h,the alloy exhibits low deformation resistance,a high degree of recrystallization,and optimal deformation coordination ability.Therefore,this represents a rational single-stage homogenization process.展开更多
It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dy...It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dynamic model for seismic analysis of risers is developed in accordance with the working environment of the risers and the influence of inertia force of the pipelines. The dynamic equations for the developed model are derived and resolved on the basis of the energy theory of beams. Numerical simulation for an engineering project in the Bohai Oil Field, China shows that the fundamental frequency of the riser plays the major role in the seismic responses, and for platforms in shallow water in Bohai Bay, the risers demonstrate a much lower stress response due to prominent differences between the riser frequency and the earthquake wave frequency. The presented model and its corresponding method for seismic analysis are practical and important for riser design resistant to earthquake waves.展开更多
基金the National Research and InnovationAgency of Indonesia (BRIN) under research grant Rumah Program Kebencanaan 2022-2025support from the Earth Observatory Singapore (EOS)supported by the Ministry of Higher Education, Science,and Technology, and Institut Teknologi Bandung through the Indonesian Collaborative Research Program.
文摘The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.
文摘A single set of 5 bird tracks was discovered in the Tianjialou Formation (Barremian-Albian) of Junan County, Shandong Province, China. After careful study we infer that it is a new type of bird tracks, and a new ichnoge- nus was erected and the name Shandongornipes was given. The characteristics of the new bird track are as follows: Moderately large tetradactyl footprints with well-developed hallux impression. Track width (about 5.8 cm) almost equal to track length (excluding hallux); total length of track (in- cluding hallux) 8.7 cm. The digit impressions are slender, with distal ends showing long sharp claw marks. Hallux pos- teriorly-directed, and hallux impressions well-developed. Digits II, III and IV point anteriorly, exhibiting mesaxonic asymmetry: divarication angle between II and III much lar- ger than that of III and IV, the former ranging from 91° to 118°, and the latter less than 30°. Divarication between digits II and IV ranging from 128° to 142°. Without web structures. Digital pads recognizable, usually at least three in digits III and IV, but sometimes only two due to preservation. The trackway shows slight positive (inward) rotation of feet. The bird tracks occur in association with abundant dinosaur tracks, and are believed to have formed in flood plain environments.
文摘The inexhaustible heat deposit in great depths （5-10 km） is a scientific fact. Such deposit occurs around the globe. Thereby, everybody is enabled to generate autonomously clean and renewable energy, ample electricity and heat. The economical exploration and exploitation of this superdeep geothermal heat deposit requires a novel drilling technique, because the currently only deep drilling method （Rotary） is limited to about 5 km, due to the rising costs, depending exponentially on depth. Electro-pulse-boring （EPB） is a valuable option to Rotary drilling. EPB, originally investigated in Russia, is ready to be developed for industrialization. The feasibility of EPB is proven by many boreholes drilled up to 200 m in granite （crystalline）. Estimates show outstanding low costs for drilling by EPB： 100 E/m for a borehole with a large diameter （φ） such as 20 （50 cm）, independent on depth and applicable likewise for sediments and crystalline rocks, such as granite. The current rate of penetration （ROP） of 3 m per hour is planned to be augmented up to 35 m per hour, and again, irrespective whether in sedimentary or crystalline formations. Consequently, a 10 km deep borehole with φ 50 cm will ultimately be drilled within 12 days. EPB will create new markets, such as： （i） EPB shallow drilling for geotechnics, energy piles, measures in order to mitigate natural hazards, etc., （ii） EPB deep drilling （3-5 km） for hydro-geothermics, exploration campaigns etc. and （iii） EPB super-deep drilling （5-10 km） for petro-geothermies, enabling the economic generation of electricity. The autonomous and unlimited supply with cost efficient electricity, besides ample heat, ensures reliably clean and renew- able energy, thus, high supply security. Such development will provide a substantial relief to cope with the global challenge to limit the climate change below 2 ℃. The diminution of fossil fuels, due to the energy transition in order to mitigate the climate change, implies likewise the decrease of air pollution.
基金Project(52174303)supported by the National Natural Science Foundation of ChinaProject(2023JH2/101700302)supported by the Joint Program of Science and Technology Plans in Liaoning Province,China。
文摘Based on microstructure analysis,diffusion theory,and hot deformation experiments,the solidification microstructure and element segregation of the Alloy 625 Plus ingot,the diffusion kinetics of Ti,Nb,and Mo during homogenization and the hot deformation behavior of the homogenized ingot were investigated in this study.The results indicate that:(1)the solidified ingot exhibits a typical dendritic microstructure,and significant element segregation occurs,leading to the presence of Ti,Nb,and Mo-rich precipitates in the interdendritic region;(2)Following homogenization,the degree of element segregation in the ingot is significantly reduced.The diffusion coefficients(D)of Ti,Nb,and Mo under various homogenization conditions were calculated.Subsequently,the diffusion constants(D_(0))and activation energies(Q)of Ti,Nb,and Mo were obtained to be 0.01432,0.00397 and 0.00195 cm^(2)/s and 244.851,230.312,and 222.125 kJ/mol,respectively.Finally,the diffusion kinetics formulas for Ti,Nb,and Mo in Alloy 625 Plus were established.After homogenization at 1220℃for 8 h,the alloy exhibits low deformation resistance,a high degree of recrystallization,and optimal deformation coordination ability.Therefore,this represents a rational single-stage homogenization process.
基金supported by the National Natural Science Foundation of China (granted number 50979113)funded by the National 863 Program of China (granted number 2006AA09A105)
文摘It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dynamic model for seismic analysis of risers is developed in accordance with the working environment of the risers and the influence of inertia force of the pipelines. The dynamic equations for the developed model are derived and resolved on the basis of the energy theory of beams. Numerical simulation for an engineering project in the Bohai Oil Field, China shows that the fundamental frequency of the riser plays the major role in the seismic responses, and for platforms in shallow water in Bohai Bay, the risers demonstrate a much lower stress response due to prominent differences between the riser frequency and the earthquake wave frequency. The presented model and its corresponding method for seismic analysis are practical and important for riser design resistant to earthquake waves.
