Mesozoic magmatism and copper polymetallic mineralization processes in the Shanghang-Datian region, Fujian Province, Southeast China   总被引：2，自引：1，他引：2  

毛建仁胡青  许乃政陈荣叶海敏  赵希林 《中国地球化学学报》2006,25(3):266-278

1IntroductionDuring the Mesozoic there occurred large-scalemagmatism and mineralization in South China.As amain part of East Asian,the South China continent isan extremely complex region,involving multi-stageMesozoic tectono-magmatism.Therefore,various hy…  相似文献   

Interaction between network and intranetwork magnetic fields     

Zhang  Jun  Wang  Jingxiu  Lee  Chik-Yin  Wang  Haimin 《Solar physics》2000,192(1-2):415-426

Using high-resolution observations of deep magnetograms and H filtergrams obtained at Big Bear Solar Observatory during 17–24 October 1997, we have studied the interaction of intranetwork and network elements. The relationship between small-scale magnetic fields and active phenomena is investigated. Most of the small-scale active phenomena are triggered by the interaction either between intranetwork and network magnetic elements or among several network elements. The energy released due to the interaction of intranetwork–network elements and network–network elements is large enough to heat the corona.  相似文献   

Magnetic Helicity Change Rate Associated with X-Class and M-Class Flares     

Klaus?HartkornEmail author  Haimin?Wang 《Solar physics》2004,225(2):311-324

We investigate the total helicity change rate of active regions during the time period of three X-class and five M-class flares using MDI full-disk magnetograms which are sufficient to calculate the advection and the shuffling terms. Two out of three regions with X-class flares show a significant change in the helicity change rate, while none of the five active regions with an associated M-class flare shows this behavior. A closer investigation of the active regions associated with a helicity change reveals certain peculiarities that point to an artificial signal due to the magnetic reversal effect. This is supported by the fact that a simulation of the reversal effect reproduces the same shape of the helicity signal, although with an amplitude one magnitude lower. We investigate active regions with no flaring activity and determine the fluctuations of the helicity change rate due to instrumental effects to be 12 × 10⁴⁰ Mx² h^-1.  相似文献   

Structure of magnetic fields on the quiet sun     

Haimin Wang 《Solar physics》1988,116(1):1-16

To obtain quantitative temporal and spatial information on the network magnetic fields, we applied auto- and cross-correlation techniques to the Big Bear videomagnetogram (VMG) data. The average size of the network magnetic elements derived from the auto-correlation curve is about 5700 km. The distance between the primary and secondary peak in the auto-correlation curve is about 17000 km, which is half of the size of the supergranule as determined from the velocity map. The correlation time is about 10 to 20 hours. The diffusion constant derived from the cross-correlation curve is 150 km² s^-1. We also found that in the quiet regions the total magnetic flux in a window 3 × 4 changes very little in nearly 10 hours. That means the emergence and the disappearance of magnetic flux are in balance. The cancelling features and the emergence of ephemeral regions are the major sources for the loss and replenishment of magnetic flux on the quiet Sun.  相似文献   

利用盐湖老卤与元明粉制取七水硫酸镁工艺研究          下载免费PDF全文

牛韩根  李海民 《盐湖研究》2017,25(3):39-45

氯化镁和硫酸钠作原料,以K~+,Na~+,Mg~(2+)//Cl~-,SO_4~2-H_2O及Na~+,Mg~(2+)//Cl~-,SO_4~2-H_2O水盐体系相图为理论依据,研究了氯化镁和硫酸钠分解转化—冷却结晶法生产七水硫酸镁的工艺路线。考察氯化镁和硫酸钠分解转化温度、分解转化时间、各物料配比关系等因素对制备七水硫酸镁的影响,确定了各试验因素对试验结果的影响主次顺序,得出了试验结果。  相似文献   

The Polarity Distribution of Intranetwork and Network Fields     

Zhang  Jun  Wang  Jingxiu  Deng  Yuanyong  Wang  Haimin 《Solar physics》1999,188(1):47-58

We have studied the relative polarity distribution of intranetwork (IN) and network (NW) fields for the first time, using very deep magnetograms obtained at Big Bear Solar Observatory (BBSO) and Huairou Solar Observation Station (HSOS). We found 80 network cells and measured the polarities of intranetwork and network magnetic flux within each cell. The analysis reveals that, in enhanced networks, the signed sum of the IN flux in a cell and the signed sum of the network flux on the boundary of the cell is opposite with 90% probability; in mixed-polarity network, the corresponding signed fluxes are opposite with a probability of 75%. We suggest that:(1) Some of the excess flux within a cell may connect to a weak field component of the IN field that is below the detection limit.(2) Some IN flux, preferentially close to the cell boundary, may be topologically connected to the network field.(3) Some observational effects might produce this anti-correlation.  相似文献   

昆特依盐湖晶间卤水25℃等温蒸发试验研究   总被引：3，自引：2，他引：1       下载免费PDF全文

李海民  王芝兰  李纪泽 《盐湖研究》1999,7(3):15-21

研究了昆特依盐湖晶间卤水２５℃等温蒸发的结晶析盐规律,测定了蒸发过程卤水的物化参数。  相似文献   

黄河水资源问题与对策研究   总被引：1，自引：0，他引：1  

牛玉国  张海敏  李世明 《湖泊科学》2004,16(Z1):16-29

黄河是中国的第二大河.黄河下游由于水资源缺乏近些年来频频发生的断流引起了人们的极大关注.黄河水资源问题日益重要,继黄河洪水、泥沙之后,成为举世瞩目的又一个热点问题.黄河水资源问题有其自身的特点,人们一直在探寻解决这个问题的好方法.本文根据长期实测资料分析介绍了黄河水资源的概况,剖析了黄河水资源开发利用中存在的问题,并对如何解决这些问题提出了建议.  相似文献   

三维解释技术在采空区富水性分析中的应用     

魏海民  严文成 《西部资源》2019,(2):155-156,160

文章针对甘肃省某矿区内的煤矿采空区积水分布情况,利用瞬变电磁法(TEM)对区内的采空区进行了探测,对于低阻特征的采空区,采用不同深度顺层切片进行综合分析,利用voxler软件对处理之后的数据进行三维成图解释。结果表明,瞬变电磁法对采空区富水性分析有着较好的辨别能力,将三维解释技术应用于采空区探测及积水性分析中,可直观清晰的识别采空区的空间位置,这为今后采空区积水分布情况的探测提供了新的解释手段。  相似文献   

A Revisit of the Masuda Flare     

Rui Liu  Yan Xu  Haimin Wang 《Solar physics》2011,269(1):67-82

We revisit the flare that occurred on 13 January 1992, which is now universally termed the “Masuda flare”. The new analysis is motivated not just by its uniqueness despite the increasing number of coronal observations in hard X-rays, but also by the improvement of Yohkoh hard X-ray image processing, which was achieved after the intensive investigations on this celebrated event. Using an uncertainty analysis, we show that the hard X-ray coronal source is located closer to the soft X-ray loop by about 5000 km (or 7 arcsec) in the re-calibrated Hard X-ray Telescope (HXT) images than in the original ones. Specifically, the centroid of the M1-band (23 – 33 keV) coronal source is above the maximum brightness of the Soft X-ray Telescope (SXT) loop by 5000±1000 km (9600 km in the original data) and above the apex of the SXT loop represented by the 30% brightness contour by 2000±1000 km (∼ 7000 km in the original data). The change is obviously significant, because most coronal sources are above the thermal loop by less than 6 arcsec. We suggest that this change may account for the discrepancy in the literature, i.e., the spectrum of the coronal emission was reported to be extremely hard below ∼ 20 keV in the pre-calibration investigations, whereas it was reported to be considerably softer in the literature after the re-calibration done by Sato, Kosugi, and Makishima (Pub. Astron. Soc. Japan 51, 127, 1999). Still, the coronal spectrum is flatter at lower energies than at higher energies, due to the lack of a similar, co-spatial source in the L-band (14 – 23 keV), for which a convincing explanation is absent.  相似文献