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41.
In order to understand the process of surface erosion and acquire basic data of conditions on hillslope without vege tation, a sprinkling experiment is conducted on a bare slope in Mt. Tanakami in the central part of Japan. Based on the mea surements of runoff, mean soil erosion depth, and sediment yield, etc. , the results suggest the following characteristics in the process of surface erosion in the experimental area. (1) The occurrence of sediment discharge is interrupted; (2) Surface runoff is a saturated overland flow; (3) The mean soil erosion depth is thick compared with other areas in Mt. Tanakami;(4) Sediment discharge process is detachment- limited. 相似文献
42.
In this paper, we reconstruct the finite energy force-free magnetic field of the active region NOAA 8100 on 4 November 1997
above the photosphere. In particular, the 3-D magnetic field structures before and after a 2B/X2 flare at 05:58 UT in this
region are analyzed. The magnetic field lines were extrapolated in close coincidence with the Yohkoh soft X-ray (SXR) loops accordingly. It is found that the active region is composed of an emerging flux loop, a complex loop
system with differential magnetic field shear, and large-scale, or open field lines. Similar magnetic connectivity has been
obtained for both instants but apparent changes of the twisting situations of the calculated magnetic field lines can be observed
that properly align with the corresponding SXR coronal loops. We conclude that this flare was triggered by the interaction
of an emerging flux loop and a large loop system with differential magnetic field shear, as well as large-scale, or open field
lines. The onset of the flare was at the common footpoints of several interacting magnetic loops and confined near the footpoints
of the emerging flux loop. The sheared configuration remained even after the energetic flare, as demonstrated by calculated
values of the twist for the loop system, which means that the active region was relaxed to a lower energy state but not completely
to the minimum energy state (two days later another X-class flare occurred in this region). 相似文献
43.
LUO Kai-li LI Bao-sheng ZHU Yi-zhi JIN He-ling ZHANG David Dian YAN Man-cun LI Hou-xin YAO Chun-xia ZHANG Yu-hongf . Department of Geography South China Normal University Guangzhou P. R. China . State Key Labor 《中国地理科学(英文版)》2001,11(4):336-342
About 70years ago,Frenc卜卜alaeohdoglst回LL sc卜dars al卜ome and a卜road卜ave successively con-HARD de Chardin P.et al.Initiated the Quaternary ducted large amount ofwork on the Later Quaternarygeologlcal research In the >alawusu River Basin of strata(TEILHARD,1924; YUAN,1978; LI,1987;desert region of Northern China and established th,ZHENG,1989; SUN et al,1996; LI et al,1993),Salawusu Formation门EILHARD,1924).Sine,then,palaeobiology… 相似文献
44.
45.
46.
The energy flow ofBranchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow
was calculated from the measurement of flesh production (12.5241kJ/m2a), egestion (517.7302kJ/m2a), metabolism (38.3273 kJ/m2a), and excretion (4.3798kJ/m2a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes.
In addition, the relationship between starvation respiration (R, mgO2/ind·d), wet weight (Ww, mg) and temperature (T, °C) were also measured, with the regression function beingR=0.008Ww0.736 e0.050T.
Project supported by NSFC (30270278, 3960019), the foundation of the government of Hubei Province (No. 2000J109), and the
foundation of Ecological Station, CAS in the Institute of Hydrobiology. 相似文献
47.
48.
The energy budget ofBellamya earuginosa in a shallow algal lake, Houhu Lake (Wuhan, China) was investigated by the measurement of flesh production (32.8 kJ/(m2·a)), egestion (337.7 kJ/(m2·a)), metabolism (246.7 kJ/(m2·a)), and estimation of excretion (21.4kJ/(m2·a)). The net growth efficiency of the species is about 10.9%, which accords with the generally reported value for gastropods.
In addition, the relationships between starvation respiration (R, mgO2/(Ind·d)), body weight (Wd, mg in dry wt) and temperature (T, °C) were also determined. The regression equationR=0.044Wd
0.537
e
0.061T
was obtained by the least square method, The measured SDA of the species is 26.51% of its gross metabolism.
Project No. 3960019 and 39430101 supported by NSFC and also a granted for the East Lake Ecological Experimental Station, CAS,
Wuhan. 相似文献
49.
Chun-sheng Li Qi-jun Fu Yu-hua Yan Shu-ying Jiang Hong-wei Li 《Chinese Astronomy and Astrophysics》1985,9(2):128-133
We propose a model of two acceleration regions, which can explain, on the basis of microwave maser caused by a “hollow-beam” distribution of electrons, the presence of millisecond spikes in the event of 1981 May 16 and their absence in the event of 1981 October 12, and the enhanced continuous emission in the latter. We have also uncovered relations among the features, e.g. the Type IIIG, Type IVDCIM and hard x-ray bursts, that accompany the microwave millisecond spikes during the impulsive phase of a large flare. 相似文献
50.
中国虚拟天文台图像处理分析工具(VO_IMPAT),是由国家天文台虚拟天文台项目组开发的一项服务,它提供了对数字巡天图像数据(Digital Sky Survey,DSS)、天文星表以及其他数据库的交互访问。VO_IMPAT的设计目的是实现多波段天文数据的融合。可以将不同波段的星表叠加到DSS底图上,如光学波段的USNO星表、近红外波段的2MASS星表、射电波段的NVSS星表和X射线波段的RASS星表。同时VO_IMPAT还可以对图像进行放大、缩小、伪彩色、等高线、直方图、尖锐化、平滑化、旋转等处理,不同的星表数据可以采用不同的颜色和图标显示。 相似文献