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PRIMI DATI SULLA PRESENZA IN BRESCIA DI CORNACCHIA GRIGIA Corvus corone cornix
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作者 GIOVANNI CORSETTI 《Natural Disaster Reduction in China》 1993年第1期251-256,共6页
RIASSUNTO-In due aree della città di Brescia si è accertata la presenza non occasionale di Cornacchiegrigie.Queste aree sono localizzate a nord ed a ovest(dove è stata rilevata la presenza di un nido)de... RIASSUNTO-In due aree della città di Brescia si è accertata la presenza non occasionale di Cornacchiegrigie.Queste aree sono localizzate a nord ed a ovest(dove è stata rilevata la presenza di un nido)del centro storico della città.La presenza delle Cornacchie è simile nelle due aree di studio e varia infunzione della stagione e della presenza umana.L’Autore discute il vantaggio adattativo di tale colonizza-zione,anche se il limite imposto dall’esiguo numero di soggetti per ora presenti impone cautela nell’inter-pretazione dei dati.First data on the presence of Hooded Crows Corvus corone cornix in Brescia(NorthernItaly).Two areas near the centre of the town of Brescia were kept under observation in the courseof the day and of the year to ascertain the non occasional presence of hooded crows.These areas arelocalized north and west from the centre of the town.The number of Hooded Crows is similar in bothareas but,throughout the year,it fluctuates with seasons and human presence.A nest presence hasbeen ascertained in the western area were the animals are more regularly present throughout the year.I argue the adaptive advantage of this colonization. 展开更多
关键词 LA CO area In PRIMI DATI SULLA PRESENZA IN BRESCIA DI CORNACCHIA GRIGIA Corvus corone cornix PI
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REAZIONI DI CORNACCHIE GRIGIE Corvus corone cornix A CONSPECIFICI MUMMIFICATI IN PARTICOLARI POSTURE E PRESENTATI IN CAMPAGNA
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作者 GIOVANNI CORSETTI TIZIANO LONDEI 《Natural Disaster Reduction in China》 1990年第1期239-241,共3页
Reaction of wild Hooded Crows to conspecific mummified in particolar postures and exposedin the field.A method for preparing bird specimens to be used as stimulus-objects in the field was tested bymeasuring the respon... Reaction of wild Hooded Crows to conspecific mummified in particolar postures and exposedin the field.A method for preparing bird specimens to be used as stimulus-objects in the field was tested bymeasuring the response of wild Hooded Crows,Corvus corone cornix.In a first series of experiments,HoodedCrows specimens were tested for general responsiveness and posture discrimination by conspecific.Moreapproaches were consistently made to Bristle-head posture than to Sleeked posture.In a combination of bristle-head specimens of different subspecies and species,C.c.corone was approached more times than C.c.cornix,whereas C.frugilegus elicited intermediate interest.In a different combination of bristle-head specimens,C.c.corone was more attractive than C.c.cornix,whereas a hybrid C.c.corone x cornix was less attractive than eachpure form.The approaches were usually aggressive.Bristle-head posture was confirmed to be a self advertisingposture and the comparisons between subspecies provided suggestions about the mechanism againsthybridation. 展开更多
关键词 LA REAZIONI DI CORNACCHIE GRIGIE Corvus corone cornix A CONSPECIFICI MUMMIFICATI IN PARTICOLARI POSTURE E PRESENTATI IN CAMPAGNA
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Global Energetics of Solar Powerful Events on 2017 September 6
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作者 Dong Li Alexander Warmuth +9 位作者 Jincheng Wang Haisheng Zhao Lei Lu Qingmin Zhang Nina Dresing Rami Vainio Christian Palmroos Miikka Paassilta Annamaria Fedeli Marie Dominique 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第9期180-193,共14页
Solar flares and coronal mass ejections(CMEs)are thought to be the most powerful events on the Sun.They can release energy as high as~10^(32)erg in tens of minutes,and also can release solar energetic particles(SEPs)i... Solar flares and coronal mass ejections(CMEs)are thought to be the most powerful events on the Sun.They can release energy as high as~10^(32)erg in tens of minutes,and also can release solar energetic particles(SEPs)into interplanetary space.We explore global energy budgets of solar major eruptions that occurred on 2017 September 6,including the energy partition of a powerful solar flare,and the energy budget of the accompanying CME and SEPs.In the wavelength range shortward of~222 nm,a major contribution of the flare radiated energy is in the soft X-ray(SXR)0.1-7 nm domain.The flare energy radiated at wavelengths of Lyαand mid-ultraviolet is larger than that radiated in the extreme ultraviolet wavelengths,but it is much less than that radiated in the SxR waveband.The total flare radiated energy could be comparable to the thermal and nonthermal energies.The energies carried by the major flare and its accompanying CME are roughly equal,and they are both powered by the magnetic free energy in the NOAA AR 12673.Moreover,the CME is efficient in accelerating SEPs,and the prompt component(whether it comes from the solar flare or the CME)contributes only a negligible fraction. 展开更多
关键词 SUN flares-Sun magnetic fields-Sun coronal mass ejections(CMEs)
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Breaking of Large-Scale Filament due to Magnetic Reconnection and Consequent Partial Eruption
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作者 Kaifeng Kang Yang Guo +2 位作者 Yan Li Jingxing Wang Jun Lin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第9期194-206,共13页
Following our previous work,we studied the partial eruption of a large-scale horse-shoe-like filament that had beenobserved in a decaying active region on the solar disk for more than 4.5 days.The filament became acti... Following our previous work,we studied the partial eruption of a large-scale horse-shoe-like filament that had beenobserved in a decaying active region on the solar disk for more than 4.5 days.The filament became active after itwas broken into two pieces,P1 and P2 seen in Hα,by magnetic reconnection between the magnetic field around itand that of a newly emerging active region nearby.P1 eventually erupted 13 hr after the breaking and escaped fromthe Sun,developing to a fast coronal mass ejection,and P2 stayed.But the mass in P1 falling down to P2 in theeruption suggests that the global magnetic fields over P1 and P2 were still connected to each other prior to theeruption.The reconnection process breaking the filament occurred outside the filament,and P1 and P2 were locatedalmost at the same altitude,so the fashion of the filament partial eruption studied here differs from that of the“double-decker model”and that of reconnection inside the filament.Analyzing the decay indices of thebackground fields above P1 and P2,n_(1)and n_(2),showed that the altitude where n_(1)exceeds the critical value of n_(c)=1.5 for the loss of equilibrium or the torus instability is lower than that where n_(2)>nc,and that n_(1)>n_(2) alwaysholds at all altitudes.Combining this fact with that the eruption occurred 13 hr after filament was broken byreconnection,we conclude that the eruption of P1 was triggered by the loss of equilibrium or the torus instability inthe configuration,and magnetic reconnection breaking the filament helped weaken the confinement of thebackground field on P1,allowing P1 to erupt.Detailed features of the eruption and the corresponding physicalscenario were also discussed. 展开更多
关键词 SUN activity-Sun filaments-prominences-Sun coronal mass ejections(CMEs)-Sun flares-Sun magnetic fields
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A Revised Graduated Cylindrical Shell Model and its Application to a Prominence Eruption
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作者 Qing-Min Zhang Zhen-Yong Hou Xian-Yong Bai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第12期63-72,共10页
In this paper,the well-known graduated cylindrical shell(GCS)model is slightly revised by introducing longitudinal and latitudinal deflections of prominences originating from active regions(ARs).Subsequently,it is app... In this paper,the well-known graduated cylindrical shell(GCS)model is slightly revised by introducing longitudinal and latitudinal deflections of prominences originating from active regions(ARs).Subsequently,it is applied to the three-dimensional(3D)reconstruction of an eruptive prominence in AR 13110,which produced an M1.7 class flare and a fast coronal mass ejection(CME)on 2022 September 23.It is revealed that the prominence undergoes acceleration from~246 to~708 km s^(-1).Meanwhile,the prominence experiences southward deflection by 15°±1°without longitudinal deflection,suggesting that the prominence erupts non-radially.Southward deflections of the prominence and associated CME are consistent,validating the results of fitting using the revised GCS model.Besides,the true speed of the CME is calculated to be 1637±15 km s^(-1),which is~2.3 times higher than that of prominence.This is indicative of continuing acceleration of the prominence during which flare magnetic reconnection reaches maximum beneath the erupting prominence.Hence,the reconstruction using the revised GCS model could successfully track a prominence in its early phase of evolution,including acceleration and deflection. 展开更多
关键词 SUN flares-Sun filaments-prominences-Sun coronal mass ejections(CMEs)
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Investigation on the Formation of Herringbone Structure in TypeⅡSolar Radio Bursts
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作者 Z.Z.Abidin A.N.Zulkiplee +1 位作者 V.Epin F.A.M.Pauzi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第5期101-109,共9页
We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November 3rd.Data from the Space Weather Prediction Center,National Oceanic and Atmospheric Administration,e-CAL... We report detailed observation of the“herringbone”of a Type II solar radio burst that occurred on 2010 November 3rd.Data from the Space Weather Prediction Center,National Oceanic and Atmospheric Administration,e-CALLISTO,and Nan?ay Radio Heliograph are analyzed.We determine the brightness temperature and degree of circular polarization of the“herringbone”burst.Correlations between the physical parameters and the“herringbone”are examined.Based on the relationship,this is the first study that suggested this“herringbone”was generated through fundamental plasma. 展开更多
关键词 SUN activity-Sun corona-Sun coronal mass ejections(CMEs)-Sun magnetic fields-Sun radio radiation
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An in Vitro Analysis to Evaluate Coronal Residual Dentine Thickness after Different Anterior Crown Preparations
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作者 Nana Frimpomah Adu-Ampomah Patrick Caldicock Ampofo +5 位作者 Anno Nyako Sandra Hewlett Alexander Oti Acheampong Gladia Toledo Mayari Yabang Stephen Ankoh Ruby Goka 《Open Journal of Stomatology》 2023年第12期442-449,共8页
Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists re... Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study. 展开更多
关键词 CORONAL Finishing Lines Residual Dentine Thickness
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Management of distal humeral coronal shear fractures 被引量:15
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作者 Shahram S Yari Nathan L Bowers +1 位作者 Miguel A Craig Lee M Reichel 《World Journal of Clinical Cases》 SCIE 2015年第5期405-417,共13页
Coronal shear fractures of the distal humerus are rare,complex fractures that can be technically challenging to manage. They usually result from a low-energy fall and direct compression of the distal humerus by the ra... Coronal shear fractures of the distal humerus are rare,complex fractures that can be technically challenging to manage. They usually result from a low-energy fall and direct compression of the distal humerus by the radial head in a hyper-extended or semi-flexed elbow or from spontaneous reduction of a posterolateral subluxation or dislocation. Due to the small number of soft tissue attachments at this site, almost all of these fractures are displaced. The incidence of distal humeral coronal shear fractures is higher among women because of the higher rate of osteoporosis in women and the difference in carrying angle between men and women. Distal humeral coronal shear fractures may occur in isolation, may be part of a complex elbow injury, or may be associated with injuries proximal or distal to the elbow. An associated lateral collateral ligament injury is seen in up to 40% and an associated radial head fracture is seen in up to 30% of these fractures. Given the complex nature of distal humeral coronal shear fractures, there is preference for operative management. Operative fixation leads to stable anatomic reduction, restores articular congruity, and allows initiation of early range-of-motion movements in the majority of cases. Several surgical exposure and fixation techniques are available to reconstruct the articular surface fol owing distal humeral coronal shear fractures. The lateral extensile approach and fixation with countersunk headless compression screws placed in an anterior-to-posterior fashion are commonly used. We have found a two-incision approach(direct anterior and lateral) that results in less soft tissue dissection and better outcomes than the lateral extensile approach in our experience. Stiffness, pain, articular incongruity, arthritis, and ulnohumeral instability may result if reduction is non-anatomic or if fixation fails. 展开更多
关键词 CORONAL Shear Fractures DISTAL HUMERUS MANAGEMENT Approach Two-incision
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Numerical Simulation of the 12 May 1997 CME Event 被引量:7
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作者 周玉芬 冯学尚 吴式灿 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第2期790-793,共4页
Our newly developed CESE MHD model is used to simulate sun-earth connection event with the well-studied 12 May 1997 CME event as an example. The main features and approximations of our numerical model are as follows:... Our newly developed CESE MHD model is used to simulate sun-earth connection event with the well-studied 12 May 1997 CME event as an example. The main features and approximations of our numerical model are as follows: (1) The modifed conservation element and solution element (CESE) numerical scheme in spherical geometry is implemented in our code. (2) The background solar wind is derived from a 3D time-dependent numerical MHD model by input measured photospheric magnetic fields. (3) Transient disturbances are derived from solar surface by introducing a mass flow of hot plasma. The numerical simulation has enabled us to predict the arrival of the interplanetary shock and provided us with a relatively satisfactory comparison with the WIND spacecraft observations. 展开更多
关键词 CORONAL MASS EJECTION SOLAR-WIND MHD SIMULATION PROPAGATION
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The Lyman-alpha Solar Telescope (LST) for the ASO-S mission——Ⅰ. Scientific objectives and overview 被引量:7
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作者 Hui Li Bo Chen +20 位作者 Li Feng Ying Li Yu Huang Jing-Wei Li Lei Lu Jian-Chao Xue Bei-Li Ying Jie Zhao Yu-Tong Yang Wei-Qun Gan Cheng Fang Ke-Fei Song Hong Wang Quan-Feng Guo Ling-Ping He Bo Zhu Cheng Zhu Lei Deng Hai-Chao Bao Cai-Xia Cao Zhong-Guang Yang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第11期23-32,共10页
As one of the payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is aimed at imaging the Sun and the inner corona up to 2.5 R⊙(mean solar radius)in both the... As one of the payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is aimed at imaging the Sun and the inner corona up to 2.5 R⊙(mean solar radius)in both the Lyα(121.6 nm)and visible wavebands with high temporo-spatial resolution,mainly targeting solar flares,coronal mass ejections(CMEs)and filaments/prominences.LST observations allow us to trace solar eruptive phenomena from the disk center to the inner corona,to study the relationships between eruptive prominences/filaments,solar flares and CMEs,to explore the dynamical processes and evolution of solar eruptions,to diagnose solar winds,and to derive physical parameters of the solar atmosphere.LST is actually an instrument suite,which consists of a Solar Disk Imager(SDI),a Solar Corona Imager(SCI),a White-light Solar Telescope(WST)and two Guide Telescopes(GTs).This is the first paper in a series of LST-related papers.In this paper,we introduce the scientific objectives,present an overview of the LST payload and describe the planned observations.The detailed design and data along with potential diagnostics are described in the second(Paper II)and third(Paper III)papers,respectively,appearing in this issue. 展开更多
关键词 SUN flares-Sun coronal mass ejections(CMEs)-Sun filaments prominences-Sun corona-Sun chromosphere-Sun UV radiation
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The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅲ. data and potential diagnostics 被引量:7
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作者 Li Feng Hui Li +13 位作者 Bo Chen Ying Li Roberto Susino Yu Huang Lei Lu Bei-Li Ying Jing-Wei Li Jian-Chao Xue Yu-Tong Yang Jie Hong Jian-Ping Li Jie Zhao Wei-Qun Gan Yan Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第11期79-92,共14页
The Lyman-alpha Solar Telescope(LST)is one of the three payloads onboard the Advanced Space-based Solar Observatory(ASO-S)mission.It aims at imaging the Sun from the disk center up to 2.5 R⊙targeting solar eruptions,... The Lyman-alpha Solar Telescope(LST)is one of the three payloads onboard the Advanced Space-based Solar Observatory(ASO-S)mission.It aims at imaging the Sun from the disk center up to 2.5 R⊙targeting solar eruptions,particularly coronal mass ejections(CMEs),solar flares,prominences/filaments and related phenomena,as well as the fast and slow solar wind.The most prominent speciality of LST is the simultaneous observation of the solar atmosphere in both Lyαand white light(WL)with high temporospatial resolution both on the solar disk and the inner corona.New observations in the Lyαline together with traditional WL observations will provide us with many new insights into solar eruptions and solar wind.LST consists of a Solar Corona Imager(SCI)with a field of view(FOV)of 1.1–2.5 R⊙,a Solar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST)with an identical FOV up to 1.2 R⊙.SCI has a dual waveband in Lyα(121.6±10 nm)and in WL(700±40 nm),while SDI works in the Lyαwaveband of 121.6±7.5 nm and WST works in the violet narrow-band continuum of 360±2.0 nm.To produce high quality science data,careful ground and in-flight calibrations are required.We present our methods for different calibrations including dark field correction,flat field correction,radiometry,instrumental polarization and optical geometry.Based on the data calibration,definitions of the data levels and processing procedures for the defined levels from raw data are described.Plasma physical diagnostics offer key ingredients to understand ejecta and plasma flows in the inner corona,as well as different features on the solar disk including flares,filaments,etc.Therefore,we are making efforts to develop various tools to detect the different features observed by LST,and then to derive their physical parameters,for example,the electron density and temperature of CMEs,the outflow velocity of the solar wind,and the hydrogen density and mass flows of prominences.Coordinated observations and data analyses with the coronagraphs onboard Solar Orbiter,PROBA-3,and Aditya are also briefly discussed. 展开更多
关键词 Sun:coronal mass ejections(CMEs) Sun:flares Sun:solar wind techniques:calibration
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The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅱ. design of LST 被引量:6
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作者 Bo Chen Hui Li +47 位作者 Ke-Fei Song Quan-Feng Guo Pei-Jie Zhang Ling-Ping He Shuang Dai Xiao-Dong Wang Hai-Feng Wang Chun-Long Liu Hong-Ji Zhang Guang Zhang Yunqi Wang Shi-Jie Liu Hong-Xin Zhang Lei Liu Shi-Lei Mao Yang Liu Jia-Hao Peng Peng Wang Liang Sun Yang Liu Zhen-Wei Han Yan-Long Wang Kun Wu Guang-Xing Ding Peng Zhou Xin Zheng Ming-Yi Xia Qing-Wen Wu Jin-Jiang Xie Ya Chen Shu-Mei Song Hong Wang Bo Zhu Chang-Bo Chu Wen-Gang Yang Li Feng Yu Huang Wei-Qun Gan Ying Li Jing-Wei Li Lei Lu Jian-Chao Xue Bei-Li Ying Ming-Zhe Sun Cheng Zhu Wei-Min Bao Lei Deng Zeng-Shan Yin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第11期33-48,共16页
As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SD... As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST).When working in-orbit,LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5 R⊙(R⊙stands for the mean solar radius)with a spatial resolution of 4.8′′and 1.2′′for coronal and disk observations,respectively,and a temporal resolution of 30–120 s and 1–120 s for coronal and disk observations,respectively.The maximum exposure time can be up to20 s due to precise pointing and image stabilization function.Among the three telescopes of LST,SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Lyα(121.6±10 nm)line and white light(WL)(700±40 nm)wavebands by using a narrowband Lyαbeam splitter and has a field of view(FOV)from 1.1 to 2.5 R⊙.The stray-light suppression level can attain<10^-6 B⊙(B⊙is the mean brightness of the solar disk)at 1.1 R⊙and≤5×10^-8 B⊙at 2.5 R⊙.SDI and WST are solar disk imagers working in the Lyαline and 360.0 nm wavebands,respectively,which adopt an off-axis two-mirror reflective structure with an FOV up to 1.2 R⊙,covering the inner coronal edge area and relating to coronal imaging.We present the up-to-date design for the LST payload. 展开更多
关键词 telescopes—instrumentation high angular resolution—Sun flares—Sun CORONAL mass ejections(CMEs)—Sun UV radiation
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Propagation of Fast Magnetoacoustic Waves in Stratified Solar Atmosphere 被引量:3
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作者 郑惠南 张元元 +2 位作者 王水 王传兵 李毅 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第2期399-402,共4页
The characteristics of magnetohydrodynamic fast wave propagation in the solar stratified atmosphere are studied by the ray tracing method. The propagation behaviour of the wavefronts is described in detail. A magnetic... The characteristics of magnetohydrodynamic fast wave propagation in the solar stratified atmosphere are studied by the ray tracing method. The propagation behaviour of the wavefronts is described in detail. A magnetic field incorporating the characteristics field spreading expected in flux tubes is used, which represents the main feature of an active region. Partly ionization is considered beside the stratified solar atmosphere consisting chromosphere, transition region and corona. The study may explain the characteristics in observations of Moreton and extraultraviolet image telescope (EIT) waves. The wavefront incurred by the disturbance initialized at the base of the transition region propagates fast initially due to strong magnetic field, and it slows down when arriving beyond the region of flux-tube. Meanwhile, the wave propagates in the corona with a more consistent speed, as seen in the observation of EIT waves. The speeds and propagated characteristics in chromosphere and corona of the wavefronts are in agreement with those observed in H~ Moreton and EIT waves, respectively. 展开更多
关键词 CORONAL MASS EJECTION MAGNETIC-FLUX MORETON WAVE H-ALPHA CHROMOSPHERE EIT SIMULATIONS MODELS
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Influence of coronal holes on CMEs in causing SEP events 被引量:3
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作者 Cheng-Long Shen Jia Yao +3 位作者 Yu-Ming Wang Pin-Zhong Ye Xue-Pu Zhao Shui Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第10期1049-1060,共12页
The issue of the influence of coronal holes (CHs) on coronal mass ejections (CMEs) in causing solar energetic particle (SEP) events is revisited. It is a continuation and extension of our previous work, in which... The issue of the influence of coronal holes (CHs) on coronal mass ejections (CMEs) in causing solar energetic particle (SEP) events is revisited. It is a continuation and extension of our previous work, in which no evident effects of CHs on CMEs in generating SEPs were found by statistically investigating 56 CME events. This result is consistent with the conclusion obtained by Kahler in 2004. We extrapolate the coronal magnetic field, define CHs as the regions consisting of only open magnetic field lines and perform a similar analysis on this issue for 76 events in total by extending the study interval to the end of 2008. Three key parameters, CH proximity, CH area and CH relative position, are involved in the analysis. The new result confirms the previous conclusion that CHs did not show any evident effect on CMEs in causing SEP events. 展开更多
关键词 acceleration of particles -- Sun coronal mass ejections -- Sun coronal holes -- Sun particle emission
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Three-dimensional imaging of the uterus:The value of the coronal plane 被引量:3
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作者 Lufee Wong Nikki White +3 位作者 Jayshree Ramkrishna Edward Araujo Júnior Simon Meagher Fabricio Da Silva Costa 《World Journal of Radiology》 CAS 2015年第12期484-493,共10页
Advent in three-dimensional(3D) imaging technology has seen 3D ultrasound establish itself as a useful adjunct complementary to traditional two-dimensional imaging of the female pelvis. This advantage largely arises f... Advent in three-dimensional(3D) imaging technology has seen 3D ultrasound establish itself as a useful adjunct complementary to traditional two-dimensional imaging of the female pelvis. This advantage largely arises from its ability to reconstruct the coronal plane of the uterus, which allows further delineation of many gynecological disorders. 3D imaging of the uterus is now the preferred imaging modality for assessing congenital uterine anomalies and intrauterine device localization. Newer indications include the diagnosis of adenomyosis. It can also add invaluable information to delineate other endometrial and myometrial pathology such as fibroids and endometrial polyps. 展开更多
关键词 Three-dimensional ultrasound Coronal view PELVIS UTERUS Uterine anomalies
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Possible Connections between X-Solar Flares and Worldwide Variation in Seismicity Enhancement 被引量:6
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作者 Marilia Hagen Anibal Azevedo 《Natural Science》 2017年第12期457-476,共20页
We developed a?statistical study analyzing global seismicity enhancement and its variation?overtwenty years.?X-flares sometimes occur in conjunction with Coronal Mass Ejections (CME),which make their connection with t... We developed a?statistical study analyzing global seismicity enhancement and its variation?overtwenty years.?X-flares sometimes occur in conjunction with Coronal Mass Ejections (CME),which make their connection with the Earth’s magnetosphere stronger.?The preliminary study divided the Earth into seven regions determined by longitude and latitude, and nine levels of depth valid for most locations?in the?Pacific area.?The results showed that X beams influenced seismicity in terrestrial localities, mainly high magnitude earthquakes occurring below the crust at 70 km.?These internal enhancements happen without the presence of any external forces such as studied in Solar Speed Winds.?Nevertheless, those variations are perceptible in the presence of intense X flares and CME and less observed in the periods during which flares were absent. Two cases of high magnitude earthquakes in recent?years are analyzed, and the extreme external conditions of those events fit?with this theory. 展开更多
关键词 Sun Solar Wind CORONAL Mass Ejections X-Flares EARTHQUAKES
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Overview of the Solar Polar Orbit Telescope Project for Space Weather Mission 被引量:3
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作者 XIONG Ming LIU Ying +20 位作者 LIU Hao LI Baoquan ZHENG Jianhua ZHANG Cheng XIA Lidong ZHANG Hongxin RAO Wei CHEN Changya SUN Weiying WU Xia DENG Yuanyong HE Han JIANG Bo WANG Yuming WANG Chuanbing SHEN Chenglong ZHANG Haiying ZHANG Shenyi YANG Xuan SANG Peng WU Ji 《空间科学学报》 CAS CSCD 北大核心 2016年第3期245-266,共22页
The Solar Polar ORbit Telescope(SPORT) project for space weather mission has been under intensive scientific and engineering background studies since it was incorporated into the Chinese Space Science Strategic Pionee... The Solar Polar ORbit Telescope(SPORT) project for space weather mission has been under intensive scientific and engineering background studies since it was incorporated into the Chinese Space Science Strategic Pioneer Project in 2011.SPORT is designed to carry a suite of remote-sensing and in-situ instruments to observe Coronal Mass Ejections(CMEs),energetic particles,solar high-latitude magnetism,and the fast solar wind from a polar orbit around the Sun.The first extended view of the polar regions of the Sun and the ecliptic enabled by SPORT will provide a unique opportunity to study CME propagation through the inner heliosphere,and the solar high-latitude magnetism giving rise to eruptions and the fast solar wind.Coordinated observations between SPORT and other spaceborne/ground-based facilities within the International Living With a Star(ILWS) framework can significantly enhance scientific output.SPORT is now competing for official selection and implementation during China's 13 th Five-Year Plan period of 2016-2020. 展开更多
关键词 Space weather Coronal mass ejection Solar magnetism Solar wind Solar energetic particle
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Sun-Moon-Earth Interactions, External Factors for Earthquakes 被引量:4
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作者 M. Hagen A. Azevedo 《Natural Science》 2017年第6期162-180,共19页
The aim of this paper is to continue analyzing the interactions in the three-body system made up of the Sun, the Moon, and the Earth. First, we review new details about Moon-Earth connections, with a special focus on ... The aim of this paper is to continue analyzing the interactions in the three-body system made up of the Sun, the Moon, and the Earth. First, we review new details about Moon-Earth connections, with a special focus on mechanical forces. Following, we expand the study to consider the pair Sun-Earth, with calculations for electromagnetic forces. The objective in both cases is to know how mechanical and electromagnetic forces affect seismological events on Earth. Our calculations found that Solar Cycles have no direct interaction with earthquake variations. Instead, we established that there is an internal discrepancy for quakes below 35 km detected in some of the regions analyzed. The results indicate that geomagnetic variations must be studied next to understand their connections to earthquakes. 展开更多
关键词 Sun MOON EARTH SOLAR Wind CORONAL Mass Ejections SOLAR Cycles EARTHQUAKES
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Relationship between CME velocities and X-ray fluxes of associated flares 被引量:3
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作者 An-Qin Chen Wei-Guo Zong 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2009年第4期470-474,共5页
Coronal mass ejection (CME) velocities have been studied over recent decades. We present a statistical analysis of the relationship between CME velocities and X-ray fluxes of the associated flares. We study two type... Coronal mass ejection (CME) velocities have been studied over recent decades. We present a statistical analysis of the relationship between CME velocities and X-ray fluxes of the associated flares. We study two types of CMEs. One is the FL type associated only with flares, while the other is the intermediate type associated with both filament eruptions and flares. It is found that the velocities of the FL type CMEs are strongly correlated with both the peak and the time-integrated X-ray fluxes of the associated flares. However, the correlations between the intermediate type CME velocities and the corre- sponding two parameters are poor. It is also found that the correlation between the CME velocities and the peak X-ray fluxes is stronger than that between the CME velocities and the time-integrated X-ray fluxes of the associated flares. 展开更多
关键词 SUN coronal mass ejections (CMEs)-Sun flares-Sun FILAMENTS
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Distribution and relative activity of matrix metalloproteinase-2 in human coronal dentin 被引量:2
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作者 Lee W. Boushell Masaru Kaku +1 位作者 Yoshiyuki Mochida Mitsuo Yamauchi 《International Journal of Oral Science》 SCIE CAS CSCD 2011年第4期192-199,共8页
The presence of matrix metalloproteinase-2 (MMP-2) in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determ... The presence of matrix metalloproteinase-2 (MMP-2) in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determine the MMP-2 distribution and relative activity in demineralized dentin. Crowns of twenty eight human molars were sectioned into inner (ID), middle (MD), and outer dentin (OD) regions and demineralized. MMP-2 was extracted with 0.33 mol·L-1 EDTA/2 mol·L-1 guanidine-HCl, pH 7.4, and MMP-2 concentration was estimated with enzyme-linked immunoabsorbant assay (ELISA). Further characterization was accomplished by Western blotting analysis and gelatin zymography. The mean concentrations of MMP-2 per mg dentin protein in the dentin regions were significantly different (P=0.043): 0.9 ng (ID), 0.4 ng (MD), and 2.2 ng (OD), respectively. The pattern of MMP-2 concentration was OD〉ID〉MD. Western blotting analysis detected -66 and -72 kDa immunopositive proteins corresponding to pro- and mature MMP-2, respectively, in the ID and MD, and a -66 kDa protein in the OD. Gelatinolytic activity consistent with MMP-2 was detected in all regions. Interestingly, the pattern of levels of Western blot immunodetection and gelatinolytic activity was MD〉ID〉OD. The eoneentration of MMP-2 in human coronal dentin was highest in the region of dentin that contains the dentinoenamel junction and least in the middle region of dentin. However, levels of Western blot immunodetection and gelatinolytic activity did not correlate with the estimated regional concentrations of MMP-2, potentially indicating region specific protein interactions. 展开更多
关键词 matrix metalloproteinase-2 human coronal dentin DISTRIBUTION gelatinolytic activity
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