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质子活动与太阳黑子群 被引量:1
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作者 洪琴芳 《云南天文台台刊》 CSCD 1994年第2期6-10,共5页
本文对太阳活动第21周、22周(1976年—1992年间)97个质子活动区进行统计分析,包括活动区的面积、型别、磁结构、半影纤维等,结果表明:75%的质子耀斑产生于面积为500≤Sp≤3000单位的黑子群中;耀斑爆发... 本文对太阳活动第21周、22周(1976年—1992年间)97个质子活动区进行统计分析,包括活动区的面积、型别、磁结构、半影纤维等,结果表明:75%的质子耀斑产生于面积为500≤Sp≤3000单位的黑子群中;耀斑爆发前一天及后一天活动区面积有显著减少;质子活动区含δ复杂磁结构的占70%;具有半影旋涡形态的质子活动区中,约77%的耀斑发生在旋涡黑子出现以后。 展开更多
关键词 太阳活动 黑子群 耀斑 质子活动
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质子耀斑活动区的再现规律 被引量:5
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作者 周树荣 吴铭蟾 倪祥斌 《空间科学学报》 CAS CSCD 北大核心 1996年第4期293-298,共6页
质子耀斑活动区再现规律的研究结果表明,日面上存在着经度方向漂移式的“活火山”,即质子活动复活体.“活火山”定期地复活,并爆发质子耀斑.其复活长周期为8—11.6年,与活动周11年周期基本一致;短周期为1—2.6年,与... 质子耀斑活动区再现规律的研究结果表明,日面上存在着经度方向漂移式的“活火山”,即质子活动复活体.“活火山”定期地复活,并爆发质子耀斑.其复活长周期为8—11.6年,与活动周11年周期基本一致;短周期为1—2.6年,与活动周峰年时间宽度一致.在22周峰年中,日面南北半球上各有一个强质子活动复活体,它们爆发峰值流量≥100pfu和≥1000Pfu的质子耀斑各占周期同类耀斑总数的70.7%和83.3%. 展开更多
关键词 太阳 质子耀斑 质子活动复活体
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太阳质子活动区 被引量:3
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作者 张桂清 《中国科学(A辑)》 CSCD 2000年第z1期103-106,共4页
设定了太阳质子活动区的含义, 分析了太阳质子活动区的特征以及与太阳质子事件相关的太阳各大气层次的爆发活动. 一些研究表明, 地震活动与太阳质子事件有密切的延迟相关性.
关键词 太阳 太阳质子活动 太阳质子事件 太阳多波段爆发
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太阳周期活动对低高度内辐射带高能质子的影响 被引量:2
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作者 师立勤 林瑞淋 +1 位作者 刘四清 郑惠南 《空间科学学报》 CAS CSCD 北大核心 2012年第6期804-811,共8页
利用NOAA-15卫星1998年到2011年近13年的高能质子全向通量观测资料,分析了一个太阳活动周内,低高度内辐射带高能质子通量的分布变化特性及其物理原因,比较了观测结果与AP8模型的不同.研究表明,低高度内辐射带高能质子通量与太阳活动水... 利用NOAA-15卫星1998年到2011年近13年的高能质子全向通量观测资料,分析了一个太阳活动周内,低高度内辐射带高能质子通量的分布变化特性及其物理原因,比较了观测结果与AP8模型的不同.研究表明,低高度内辐射带高能质子通量与太阳活动水平的反相关关系与磁壳参数L值及磁场B值有关;L值越低,B值越大的空间点,其高能质子通量与太阳活动水平的反向相关性越明显.高能质子通量随太阳活动水平的变化存在明显滞后现象,L值越高、B值越小的空间点,滞后现象就越明显,滞后严重时可以达到一年左右的时间;这种滞后现象反映出低高度内辐射带高能质子的源与损失达到平衡是一个中长期过程.通过与AP8模型计算结果的比较分析可以看出,利用AP8模型时,仅考虑地磁场长期变化对质子通量的影响可能会夸大低高度内辐射带局部高能质子通量的增强. 展开更多
关键词 高能质子 辐射带 太阳活动 南大西洋异常区
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质子耀斑的日面分布特征 被引量:1
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作者 周树荣 《天文学报》 CSCD 北大核心 1994年第3期333-336,共4页
在22太阳活动周中,日面上有三个较强的质子活动复活体,它们爆发峰值流量≥100pfu和≥1000pfu的质子耀斑各占同类耀斑总数的70.4%和83.3%。活动复活体分别位于北纬26°─35°和南纬20°─... 在22太阳活动周中,日面上有三个较强的质子活动复活体,它们爆发峰值流量≥100pfu和≥1000pfu的质子耀斑各占同类耀斑总数的70.4%和83.3%。活动复活体分别位于北纬26°─35°和南纬20°─29°纬度带上,由于它们周期性(1─2.6年)地再现,从而形成了日面质子耀斑的活动经度和纬度明显集中趋势。 展开更多
关键词 耀斑 质子活动 日面分布
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Solar Forcing on Makkah AI-Mukaramah Flash Floods
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作者 Shahinaz Yousef Yasser H.O. Algafari +1 位作者 Zaki AI-Mostafa Mutaz Kordi 《Journal of Earth Science and Engineering》 2012年第2期77-83,共7页
Severe solar events manifested by highly energetic X-Ray events accompanied by coronal mass ejections and proton flares caused flash floods in Makkah AI-Mukaramab, A1-Madinah AI-Munawarah and Jeddah. The responses can... Severe solar events manifested by highly energetic X-Ray events accompanied by coronal mass ejections and proton flares caused flash floods in Makkah AI-Mukaramab, A1-Madinah AI-Munawarah and Jeddah. The responses can be prompt, delayed or prompt-delayed, suggesting that the protons entered the troposphere either through the opening of a direct gate in the magnetosphere to the location concer.led due to magnetic reconnection, through the polar gates or through those two paths respectively. The authors suggest that there is a magnetic anomaly in Makkah AI-Mukaramah area which makes it liable to be subjected to flash floods. The width of the solar streams determines the width of the gate opened in the magnetosphere via magnetic reconnection and thus narrow streams affect only one location of the three cities while extended width streams can cause flash floods in all of Makkah AI-Mukaramah AI-Madinah AI Munawarah and Jeddah. In addition, the November 24-26 Jeddah flash flood could be attributed to a prompt event due to a moderately fast solar stream that arrived the earth on those days. 展开更多
关键词 Makkah AI-Mukaramah Al-Madinah AI-Munawarah Jeddah coronal mass ejections X-ray events flash floods.
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Effects of chilled storage and cryopreservation on sperm characteristics, antioxidant enzyme activities, and lipid peroxidation in Pacific cod Gadus macrocephalus 被引量:1
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作者 王学颖 史雪辉 +4 位作者 柳意樊 于道德 官曙光 刘清华 李军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期763-771,共9页
The present study evaluated the ef fects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm mot... The present study evaluated the ef fects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm motility and the activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GPx), glutathione reductase(Gr), and lipid peroxidation(measured via malondialdehyde(MDA) content) were determined after the milt was stored at 4°C for 12 h, cryopreserved without cryoprotectant in 12% propylene glycol(PG), cryopreserved in 12% PG+0.1 mol/L trehalose, or cryopreserved in 12% PG spermatozoa but centrifuged to decant the supernatant prior to cryopreservation(only sperm cells were cryopreserved). After chilled storage or cryopreservation, the SOD, CAT and GPx activities were reduced in sperm cells and increased in seminal plasma in almost all treatments; sperm motility parameters were also decreased. However, the addition of trehalose into the cryoprotectant could signifi cantly improve the postthaw sperm quality as revealed by the sperm average path velocity. This improvement might be attributed to the function of trehalose in scavenging reactive oxygen species. Chilled storage and cryopreservation had signifi cant eff ects on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod. 展开更多
关键词 Pacific cod SPERM seminal plasma CRYOPRESERVATION sperm physiology
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The contribution of trace elements from seawater to chimneys:a case study of the native sulfur chimneys in the sea area off Kueishantao,northeast of Taiwan Island
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作者 刘长华 汪小妹 +2 位作者 靳新娣 曾志刚 陈镇东 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期162-171,共10页
Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid f... Hydrothermal fuid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater's little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep elements, cannot be used to study the seawater's seawater hydrothermal activity, containing complex contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition (over 99%), and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). By analyzing the data, we consider C-layer (secondary inner-layer) as the framework layer of the chimney which formed early (Fig.4), and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37×10^4 L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys. 展开更多
关键词 seafloor hydrothermal activity CHIMNEY native sulfur trace element
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Glyconanomaterials: Emerging applications in biomedical research 被引量:2
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作者 Xuan Chen Olof Ramstrom Mingdi Yan 《Nano Research》 SCIE EI CAS CSCD 2014年第10期1381-1403,共23页
Carbohydrates constitute the most abundant organic matter in nature, serving as structural components and energy sources, and mediating a wide range of cellular activities. The emergence of nanomaterials with distinct... Carbohydrates constitute the most abundant organic matter in nature, serving as structural components and energy sources, and mediating a wide range of cellular activities. The emergence of nanomaterials with distinct optical, magnetic, and electronic properties has witnessed a rapid adoption of these materials for biomedical research and applications. Nanomaterials of various shapes and sizes having large specific surface areas can be used as multivalent scaffolds to present carbohydrate ligands. The resulting glyconanomaterials effectively amplify the glycan-mediated interactions, making it possible to use these materials for sensing, imaging, diagnosis, and therapy. In this review, we summarize the synthetic strategies for the preparation of various glyconanomaterials. Examples are given where these glyconanomaterials have been used in sensing and differentiation of proteins and cells, as well as in imaging glycan-medicated cellular responses. 展开更多
关键词 glyconanomaterials carbohydrates IMAGING THERAPY
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Cluster of solar active regions and onset of coronal mass ejections 被引量:4
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作者 WANG JingXiu ZHANG YuZong +3 位作者 HE Han CHEN AnQin JIN ChunLan ZHOU GuiPing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第9期95-102,共8页
round-the-clock solar observations with full-disk coverage of vector magnetograms and multi-wavelength images demonstrate that solar active regions(ARs) are ultimately connected with magnetic field. Often two or more ... round-the-clock solar observations with full-disk coverage of vector magnetograms and multi-wavelength images demonstrate that solar active regions(ARs) are ultimately connected with magnetic field. Often two or more ARs are clustered, creating a favorable magnetic environment for the onset of coronal mass ejections(CMEs). In this work, we describe a new type of magnetic complex: cluster of solar ARs. An AR cluster is referred to as the close connection of two or more ARs which are located in nearly the same latitude and a narrow span of longitude. We illustrate three examples of AR clusters, each of which has two ARs connected and formed a common dome of magnetic flux system. They are clusters of NOAA(i.e., National Oceanic and Atmospheric Administration) ARs 11226 & 11227, 11429 & 11430, and 11525 & 11524. In these AR clusters, CME initiations were often tied to the instability of the magnetic structures connecting two partner ARs, in the form of inter-connecting loops and/or channeling filaments between the two ARs. We show the evidence that, at least, some of the flare/CMEs in an AR cluster are not a phenomenon of a single AR, but the result of magnetic interaction in the whole AR cluster. The observations shed new light on understanding the mechanism(s) of solar activity. Instead of the simple bipolar topology as suggested by the so-called standard flare model, a multi-bipolar magnetic topology is more common to host the violent solar activity in solar atmosphere. 展开更多
关键词 ACTIVITY coronal mass ejection magnetic fields
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Single nucleotide polymorphisms in the human corticosteroid-binding globulin promoter alter transcriptional activity 被引量:1
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作者 LI Yue WU Liang +4 位作者 LEI JingHui ZHU Cheng WANG HongMei YU XiaoGuang LIN HaiYan 《Science China(Life Sciences)》 SCIE CAS 2012年第8期699-708,共10页
Corticosteroid-binding globulin(CBG) is a high-affinity plasma protein that transports glucocorticoids and progesterone.Others and we have reported non-synonymous single nucleotide polymorphisms(SNPs) that influence C... Corticosteroid-binding globulin(CBG) is a high-affinity plasma protein that transports glucocorticoids and progesterone.Others and we have reported non-synonymous single nucleotide polymorphisms(SNPs) that influence CBG production or steroid-binding activity.However,no promoter polymorphisms affecting the transcription of human CBG gene(Cbg) have been reported.In the present study we investigated function implications of six promoter SNPs,including 26 C/G,54 C/T,144 G/C,161 A/G,205 C/A,and 443/444 AG/,five of which are located within the first 205 base pairs of 5'-flanking region and close to the highly conserved footprinted elements,TATA-box,or CCAAT-box.Luciferase reporter assays demonstrated that basal activity of the promoter carrying 54 T or 161 G was significantly enhanced.The first three polymorphisms,26 C/G,54 C/T,and 144 G/C located close to the putative hepatic nuclear factor(HNF) 1 binding elements,altered the transactivation effect of HNF1.We also found a negative promoter response to dexamethasone-activated glucocorticoid receptor(GR),although none of the SNPs affected its transrepression function.Our results suggest that human Cbg 26 C/G,54 C/T,144 G/C,and 161 A/G promoter polymorphisms alter transcriptional activity,and further studies are awaited to explore their association with physiological and pathological conditions. 展开更多
关键词 corticosteroid-binding globulin single nucleotide polymorphism hepatic nuclear factor 1
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