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山东是饮用天然矿泉水资源大省 ,点之多、量之丰居全国前列。到目前为止 ,已鉴定矿泉水 36 1处 ,其中锶型118处 ,偏硅酸型 6 4处 ,锶偏硅酸型 15 1处 ,碘型等其它类型 2 8处。这些矿泉水所赋存的岩石类型多、岩性复杂且受断裂构造控制明显 ;具有达标元素较单一、水化学类型复杂、矿化程度较低、单井允许开采量相差悬殊且地域分布不均等特点。勘查与评价重点是寻找奇缺且又可能存在的锌型、锂型、碳酸型矿泉水。开发好矿泉水资源、实行规模开发、打造本省名牌、加强矿泉水资源的卫生防护与保护 ,对于确保山东矿泉水资源的持续开发与利用具有重要意义。 相似文献
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Slavek M. Rucinski 《Monthly notices of the Royal Astronomical Society》2006,368(3):1319-1322
The luminosity function for contact binary stars of the W UMa type is evaluated on the basis of the All Sky Automated Survey (ASAS) photometric project covering all stars south of δ=+ 28° within a magnitude range 8 < V < 13 . Lack of colour indices enforced a limitation to 3374 systems with P < 0.562 d (i.e. 73 per cent of all systems with P < 1 d ) where a simplified MV (log P ) calibration could be used. The spatial density relative to the main-sequence FGK stars of 0.2 per cent, as established previously from the Hipparcos sample to V = 7.5 , is confirmed. While the numbers of contact binaries in the ASAS are large and thus the statistical uncertainties small, derivation of the luminosity function required a correction for missed systems with small amplitudes and with orbital periods longer than 0.562 d; the correction, by a factor of 3, carries an uncertainty of about 30 per cent. 相似文献
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Miguel Cerviño 《Astrophysics and Space Science》2003,284(2):897-900
Evolutionary synthesis models have been used to study the physical properties of unresolved populations in a wide range of
scenarios. Unfortunately, their self-consistency is difficult to test and there are some theoretical open questions without
an answer: (1) The change of the homology relations assumed in the computation of isochrones due to the effect of stellar
winds (or rotation) and the discontinuities in the stellar evolution are not considered. (2) There is no consensus about how
the isochrones must be integrated. (3) The discreteness of the stellar populations (that produce an intrinsic statistical
dispersion) usually are not taken into account, and model results are interpreted in a deterministic way instead of a statistical
one. The objective of this contribution is to present some inconsistencies in the computation and some cautions in the application
of the results of such codes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
89.
1IntroductionOne of the key factors related to basin geody-namics is deep process controlling formation and evolution of sedimentary basin. Depth and tempera-ture of asthenosphere,existence of mantle plume,occurrence of mantle melting,and amounts of melts under depressurization during thinning of lithosphere are controlling factors influenced formation and characteristics of extensional basin directly (Li,1994). Rifting is probably governed by frictional forces exerted on the base of litho… 相似文献
90.
Rodger I. Thompson 《Astrophysics and Space Science》2003,284(2):353-356
Tests and constraints on current theories of galaxy formation and evolution are presented. They are derived from observations
of the Northern Hubble Deep Field with WFPC2 and NICMOS. Photometric redshifts, extinctions and spectral energy distributions
are calculated for all objects in the field. The tests and constraints are derived from the output of this analysis. The tests
of the predictions from hierarchical and pure luminosity evolution galaxy evolution calculations favor the hierarchical model.
Constraints are provided by the current luminosity function and its evolution to a redshift of 6.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献