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51.
Zongjun Ning 《Solar physics》2008,247(1):53-62
This paper explores the time evolution of microwave and hard X-ray spectral indexes in the solar flare observed by Nobeyama
Radio Polarimeters (NoRP) and the Ramaty High Energy Solar Spectroscopy Imager (RHESSI) on 13 December 2006. The microwave
spectral index, γ
MW, is derived from the emissions at two frequencies, 17 and 35 GHz, and hard X-ray spectral index, γ
HXR, is derived from RHESSI spectra. Fifteen subpeaks are detected at the microwave and hard X-ray emissions. The microwave spectral
indexes tend to be harder than hard X-ray spectral indexes during the flare, which is consistent with previous findings. All
detected subpeaks follow the soft-hard-soft spectral behaviours in the hard X-ray rise-peak-decay phases. However, the corresponding
microwave subpeaks display different spectral behaviour, such as soft-hard-soft, soft-hard-harder, soft-hard-soft + hard or
irregular patterns. These contradictions reveal the complicated acceleration mechanism for low- and high-energy electrons
during this event. It is also interesting that the microwave interpeak spectral indexes are much more consistent with one
another. 相似文献
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当前,全球面临能源新技术的重大变革,发展清洁低碳能源成为新潮流。而干热岩作为一种清洁能源且具有巨大的开发潜力,更是受到了社会各界人士的广泛关注。就目前来说,干热岩的研究还处于起步阶段,在靶区确定上存在很大困难。文章通过Landsat8冬季的遥感影像数据,利用Envi5.3软件对其进行754波段假彩色合成,人工解译出线环形构造;采用大气校正法,结合当地气温,排除城镇建筑物的影响,反演出地表温度和利用遥感影像来提取羟基蚀变信息。并对解译结果进行分级。然后将研究区以30个市行政区为基本评价单元,利用已收集的山东省地热资料,航磁重力异常数据,结合专家打分法与层次分析法进行权重叠加,最后运用综合评价公式对评价单元打分,得分较高的即为干热岩开发适宜区。适宜区主要是日照市,较适宜区有招远市、栖霞市、诸城市、五莲县、莒南县、青岛市、即墨区,其他市区相比较不适宜。此次研究将对改善地方投资、带动地方资源利用发挥重要作用,对有效改善鲁东地区能源供应结构、促进经济社会可持续发展具有良好的社会效益。 相似文献
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通过对测边控制网精度严密的估算和实例分析,从理论和实践上皆证明,经过精心的设计和施测前的仪器、设备细致而周密的检校,测边控制网的精度能够满足平均边长较短的精密控制网的要求,并且相对于其他网型的控制网有其显著的效率优势和灵活的布网优势。 相似文献
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黑色葡萄状穗霉纤维素酶的纯化和性质 总被引：2，自引：0，他引：2
将筛选所得的黑色葡萄状穗霉 (Stachybotrys atra) S6 0 7发酵培养 96 h,发酵液离心去除菌体 ,上清液经超滤、Sephadex- G10 0柱层析、DEAE- Sepharose fast flow弱阴离子交换层析、CM-Sepharose fast flow阳离子交换层析、Q- Sepharose fast flow强阴离子交换层析及置换层析等步骤 ,得到了 4种电泳纯的酶组分 ,即内切纤维素酶 EG 、EG 、EG 和 β葡萄糖苷酶 (β Gase)。利用 SDS- PAGE测得 4种酶组分的分子量分别是 78.3、5 8.1、72 .4和 5 5 .6 k Da。 3种内切酶组分的最适温度都是 5 0℃ ,β-葡萄糖苷酶为 5 5℃ ,它们的最适 p H值分别是 6 .0、7.0、6 .5和 6 .0。底物专一性的实验表明 ,内切酶 、 、 都可作用于木聚糖。 相似文献
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A total of 117 agar-decomposing cultures were isolated from coastal seawater around Qingdao,China.The phenotypic and agarolytic features of an agarolytic isolate,QM38,were investigated.The strain was gram negative,strictly aerobic,curved rod and polar flagellum.On the basis of several phenotypic characters,biochemical and morphological characters and phylogenetic analysis of the gene coding for the 16S rRNA,the strain was identified as Agarivorans albus strain QM38.This strain can liquefy the agar on the solid agar plate.An excellular agarase activity was determined in liquid culture.The enzyme exhibited maximal activity at 40℃,pH 7.6.Its activity was greatly affected by different concentrations of agarose.The highest activity 32 U/ml was achieved in the culture supernatant.The hydrolytic product was analyzed by fluorophore-assisted carbohydrate electrophoresis (FACE).After complete hydrolysis of agarose,a series of agaro-oligosaccharides were produced.The main products of the enzymes were oligosaccharides in the degree of polymerization (DP) of 2,4,6 and 8.Three genes agaD01,agaD02 and agaD03,encoding β-agarases,had been cloned from genomic DNA of Agarivorans albus strain QM38.The open reading frame of agaD01,consisted of 2 988 bp,and shared 95.5%-98.9% identity to the β-agarase genes of some strains of Vibrio and Agarivorans.Gene agaD02 comprised 2 868 bp and encoded a 955-amino-acid protein.It showed 97.4% and 98.7% identity to the β-agarase genes of strain Vibrio sp.PO-303 and strain Vibrio sp.JT0107,respectively.Only partial sequence of agaD03 gene has been cloned.It showed 96.5% identity to β-agarase gene (agaB) of Pseudoalteromonas sp.CY24,and shared 96.8% identity to β-agarase-c gene of Vibrio sp.PO-303. 相似文献
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Zongjun Ning Qijun Fu Yihua Yan Yuying Liu Quankang Lu 《Astrophysics and Space Science》2001,277(4):615-624
The 2.60–3.80 GHz spectrometer at the Beijing Astronomical Observatory (BAO) recorded a ‘decimetric pulsation’ event (DCIM)
around the time 1999 0216 0300. At the beginning and end of this DCIM, two groups of reverse slope type III bursts (RS-III)
are also detected; meanwhile, metric type II bursts are recorded by CULG and HIRA during the same time. These solar radio
bursts on that day might be caused by the same active region 8458 and a same flare. We present a plausible qualitative model
for all of them.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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为了解不同农业施肥管理方式对水体浮游植物群落的影响,本研究以江苏句容戴庄有机示范村和常规农业管理区池塘浮游植物为对象,分析冬夏两季浮游植物群落特征及相关水环境因子.结果表明：冬季有机和常规农业区域的浮游植物分别检到7门95种和7门111种,夏季分别检到7门102种和6门112种,有机农业区浮游植物由冬季的隐藻—绿藻型向夏季的蓝藻—绿藻型变化,常规农业区从隐藻—绿藻型向蓝藻—硅藻型变化,蓝藻逐渐取代隐藻的优势地位.夏季各池塘浮游植物alpha多样性没有显著的区域差异,但冬季常规农业区浮游植物物种丰富度、蓝藻和裸藻的Shannon-Wiener多样性指数显著较高.指示物种分析显示,谷皮菱形藻(Nitzschia palea)和梅尼小环藻(Cyclotella meneghiniana)为有机农业区指示物种,而梭形裸藻(Euglena acus)、针形纤维藻(Ankistrodesmus acicularis)、肘状针杆藻(Synedra ulna)和狭形纤维藻(Ankistrodesmus angustus)为常规农业区指示物种,此6种藻为中、富营养化藻类,说明水体氮磷营养盐浓度较高,这与... 相似文献