太阳22周峰年若干特点     

曹莹  李维宝 《天文研究与技术》1995,(2)

本文讨论了第２２太阳活动周的下列重要特点：１．呈现双峰，并在双峰期的槽中又突起孤立的单峰。２．黑子面积峰值滞后相对数峰值的仅占１６．６７％；黑子面积与相对数同步占５８．３３％；二者峰值不能对应占２５％。３．１９８６年１０月以后，纬度≥３０°的有半影的黑子群共出现８７群；延迟在峰年期间出现的有５３群，占６０．９２％；对应有Ｍ级以上Ｘ射线爆发的活动区１８个，占２０．６９％。这一现象与“蝴蝶图”规律不符。  相似文献   

The soils on the calcareous sand dunes southeast of South Australia     

K. Urushibara-Yoshino 《Environmental Geology》1996,28(3):154-160

 The properties of soils on previously dated sand dunes from Robe to Naracoorte in South Australia were examined. In these areas younger sand dunes are composed of fresh sand, but older sand dunes are composed of calcarenited sand. The soils on the sand dunes developed successionally by the age of sand dunes. The soil properties of these sand dunes differ depending on the ages of the sand dunes. The properties of sand particles in soils are as follows: (1) On the sand dunes of 4300 years B.P., A/C profile developed (Rendzina). On the sand dunes older than 125 000 years B.P. and on the plateau of Tertiary limestone, soil profiles of A₁/AB/B/C on the sand dunes of 83 000 years B.P. and A₁/A₃/B₁/B₂/C (Terra rossa) are well developed. (2) Within the sand of A/C horizons of the sand dunes with the age of 4300 year B.P., the calcite grain content is about 64%, and the quartz content is about 35%. Within the B horizons of soils on the dunes from 83 000 years B.P. to 347 000 years B.P., the calcite grain content is only 1–2%; however, the quartz grain content is about 92%. In the B₂ horizons of soils on the dune of 690 000 years B.P. and on the Tertiary plateau, there are some calcite grains but the quartz grain content is about 96%. (3) The average size of quartz grains in the soils on the sand dunes from 4300 B.P. to 347 000 years B.P. is generally smaller, but the average size of quartz on the sand dunes of 690 000 year B.P. becomes larger and the grains are well rounded. On the Tertiary limestone plateau, the average quartz size becomes again smaller, and the grains are more rounded. (4) Fe_t in B₂ horizon of the soil profiles increases clearly corresponding to the age. Iron activity expressed by Fe_o/Fe_d also shows a close relation to the chronological sequence. The B horizon of the soil profiles shows a drastic decrease of Fe_o/Fe_d according to the age. Iron crystalinity, (Fe_d-Fe_o)/Fe_t, has a tendency for a positive relation with increasing age. Received: 1 June 1995 · Accepted: 4 December 1995  相似文献   

Adaptive Smoothing Method For Computer Derivation of K-Indices     

Krzysztof Nowo&#;y&#;ski  Tomasz Ernst  Jerzy Jankowski 《Geophysical Journal International》1991,104(1):85-93

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1991年3月5日的喷泉状爆发日珥及视向速度分布     

钟树华 《天文研究与技术》1995,(3)

本文介绍了１９９１年３月５日一个与３Ｎ级光学耀斑伴生的喷泉状爆发日珥。用Ｈα线观测从开始到结束整个过程共持续约５０分钟时间，日珥的最大投影高度１５．９万公里，视向速度分布表明，日珥主要以较大的速度向着观测者的运动，最大速度每秒１２０公里。  相似文献   

Studies on immunodiagnosis of hepatopancreatic parvo-like virus diseases ofPenaeus orientalis     

Sun Xiuqin  Wang Wenxin  Shao Jijun  Zhang Jinxin  Lu Ying  Xue Qinggang  Song Qinyun 《中国海洋湖沼学报》1993,11(3):245-248

This paper describes a rapid procedure for diagnosis of penaeid viral disease using the immune serological method. The SPA (Staphylococcal Protein A) coagglutination test in early diagnosis of penaeid viral disease has yielded satisfactory results. This is the first time SPA is used in China for diagnoses of viral diseases of marine invertebrates, especially penaeid shrimp. The SPA early diagnostic method is characterized by accuracy, rapidity, simplicity and convenience, low cost, high specificity, strong sensitivity and micro-detectability, and easy dissemination and adaptability in prawn farms.  相似文献   

The evaluation of eco-environmental susceptibility to human activity in Yulin region   总被引：1，自引：0，他引：1  

Liding Chen  Bojie Fu 《中国地理科学(英文版)》1995,6(1):57-65

The eco-environmental susceptibility is to demonstrate the reaction of a ecosystem under the same influences of the human activity. It comprise many influencing factors which have a complicated relation to the eco-environmental susceptibility. In this paper, the Analysis of Hierarchy Process (AHP) is used to determine the weight of each factor to the eco-environmental susceptibility through analyzing the relationship between human activity and environmental deterioration. And the weighted summation method is used to calculate the eco-environmental susceptibility of different divisions in Yulin region. The result shows that the loess hilly and gully area is more subjective to deteriorating eco-environment than the desert area because of the strong human activity and severe soil erosion. The project is supported by the National Natural Science Foundation of China  相似文献   

The early Cretaceous marine transgression and its significance for landscape interpretation     

《The Australian geographer》1991,22(2):178-184

Significant elements of the Australian landscape date from Mesozoic or earlier times. Australia did not separate completely from other Gondwanan components until Early Tertiary times and these Mesozoic and older elements can therefore be regarded as Gondwanan. During the separation and northern drift of the continent and particularly in Late Jurassic and earlier Cretaceous times the sea invaded and spread across much of the erstwhile landmass. The associated sediments not only covered and preserved much of the pre‐existing land surface, but they also augmented the effects of thalassostatic loading of the basins, causing further subsidence. Hinge lines developed near the coastal zones of the times, so that subsidence of the basins caused adjacent land masses to rise. Many old land surfaces have been re‐exposed at the former oceanic margins, but epigene forms are preserved high in the relief on the uplifted blocks. They survive partly because, as Crickmay (1976) suggested, rivers effectively erode at and near their channels; the divides remain untouched. A reinforcement effect also operates because the valleys are wet sites, the interfluves dry. Hence weathering and erosion proceed apace in the former while the latter are stable, allowing palaeoforms to survive.  相似文献   

The time-dependent transport of cosmic rays in the heliosphere     

Marius S. Potgieter 《Astrophysics and Space Science》1995,230(1-2):393-403

The modulation of cosmic rays (CRs) in the heliosphere is a dynamic and therefore a highly time-dependent process. Numerical models with only a time-dependent neutral sheet prove to be successful when moderate to low solar activity occurs but fail to describe large and discrete steps in modulated CRs when solar activity is high. To explain this feature of heliospheric modulation, the concept of global merged interaction regions (GMIRs) is required. The combination of gradient, curvature and neutral sheet drifts with these GMIRs has so far been the most successful approach in explaining the 11-year and 22-year cycles in the long-term modulation of CRs.  相似文献   

Study on respiratory electron transport system （ETS） of phytoplankton in Taiwan Strait and Xiamen Harbour   总被引：1，自引：0，他引：1  

黄邦钦洪华生  徐宪忠刘媛 《中国海洋湖沼学报》2005,23(2):176-182

Phytoplankton respiratory electron transport system (P-ETS) activities were studied in two cruises in Taiwan Strait (Aug. 1997 and Feb. -Mar.1998) and two cruises in Xiamen Harbour (Oct., 1997 and Apr.,1998). Results showed that P-ETS activity in the surface water of southern Yaiwan Strait in summer was homogeneous [mean value of 0.106 μ102/(L.h)], inhomogeneous in northern Yaiwan Strait in winter. Variation of P-ETS activity in middle part of the Strait was not obvious between summer and winter. Mean P-ETS activity of Xiamen Harbour in autumn was 0.255 μ102/(L.h) with a little higher value in Jiulong River estuary areas. In spring, P-ETS activity was more homogeneously distributed and the mean value was 1.076 μ102/(L.h). P-ETS activity in spring was obviously higher than in autumn in Xiamen Harbour. Vertical distribution of P-ETS in Taiwan Strait was homogeneous at some stations in winter and in summer. An obvious daily variation of P-ETS activity was recorded at Stn 9837, high at midnight and low in the early morning. Significant correlation between P-ETS activity and Chl-a was observed. Results also showed that the ratio of estimated respiratory rate to photosynthetic rate varied seasonally, high in winter (0.41) and low in summer (0.12).  相似文献   

Magnetic fields at the surfaces of stars     

J. D. Landstreet 《Astronomy and Astrophysics Review》1992,4(1):35-77

Summary Magnetic fields have now been detected in stars in several parts of the Hertzsprung-Russell diagram. Roughly dipolar fields ranging in strength between 3× 10² and 3×10⁴ G are found in many chemically peculiar A and B main sequence stars. Dipolar fields are also found in some 2–3% of white dwarfs, but with strengths between 1×10⁶ and 5×10⁸ G. In both these types of stars, the observed fields vary as the underlying star turns, but do not change in a secular manner. In solartype stars, structurally complex fields of a few kG are found with filling factors of the order of 0.1 to 0.8. Further indirect evidence of fields in cool main sequence stars is provided by detection of visible and ultraviolet line emission (chromospheric activity), x radiation (coronal matter), and giant starspots. In this review, we survey the observations of stellar magnetism in all these types of stars, as well as efforts to model the observed magnetic fields and associated photospheric peculiarities and activity.This article was processed by the author using the Springer-Verlag T_EX AAR macro package 1991.  相似文献