矿物科学的理论结构

矿物科学作为一个具有众多分支学科的学科体系,从本质上讲,其理论组成主要包括矿物及其性质两大部分。矿物科学作为一个具有比较严密理论的学科,其理论结构是由一个内核及其扩展或衍生的若干个保护层组成。矿物科学理论内核是矿物学,因为矿物学比较稳定而且难于动摇的基本理论和基本概念,已成为矿物科学的最基本部分与立论的基础。矿物科学的保护层是由它的三大分支学科群,即基础扩展分支学科群．学科交叉与应用分支学科群,以及测试分析理论与技术分支学科群组成．它们之间是相互支撑、相互补充的关系。矿物科学作为一个新兴学科,其理论内核需要不断加以充实和加固,而保护层更需要进一步加强和扩大。因此,矿物科学具有巨大的发展空间和十分光明的发展前号。     

Geoarchaeological dating of petroglyphs at lake Onega,Russia

This article introduces a new quantitative method of dating petroglyphs and describes its initial application. First, the major recent developments in the field of rock art dating are briefly reviewed, and the continuing difficulties in the dating of petroglyphs are elucidated. The archaeological background of the Lake Onega art, its geological setting and archaeogeophysical dating are explained. The theory of microerosion dating is described, together with its first practical application at the site Besov Nos on the shore of Lake Onega. The article concludes with a brief discussion of the new method's advantages and disadvantages. © 1993 John Wiley & Sons, Inc.     

基于状态参数的粗粒土应变软化和剪胀性模型研究

基于状态参数的概念,将粗粒土峰值应力比和剪胀比视为状态参数的函数,同时考虑初始模量随围压的变化,提出了一个弹塑性模型和模型参数的确定方法。该模型形式较简单,概念清晰,可以描述较大的密度和压力范围内粗粒土的应变软化和剪胀性,以及它们对物理状态和有效围压的依赖性。通过比较模型预测与粗粒土的三轴试验结果,证明了模型的合理性。     

Loch lomond stadial glacier at Fan Hir,Mynydd Du (Brecon Beacons), South Wales: Critical evidence and palaeoclimatic implications

The c. 1·2 km long, up to c. 25 m high ridge east of the almost north-south aligned Fan Hir scarp, Mynydd Du, South Wales has been regarded as a remarkable protalus rampart formed in the Loch Lomond Stadial (c. 11–10000 years BP ). New data are presented which indicate that it is a moraine. The main points supporting this glacigenic origin are: its curved plan form at the lower, southern end; its scale and the ample depth for snow to glacier ice transformation; the presence of subsidiary ridges interpreted as recessional moraines; the exceptional rate of rockwall retreat required if it were a protalus rampart; and, most importantly, the presence in the ridge of matrix-supported abraded clasts, up to 20% of which are striated. Useful criteria for differentiating moraines and protalus ramparts are thereby proposed and a sound basis is provided for palaeoclimatic reconstruction. Palaeoclimatic inferences imply that the glacier owed its existence to the combined effect of a mean July temperature of c. 8·5°C and topographically enhanced accumulation, nearly half of which was from wind-blown snow.     

堇青石低热膨胀机理研究

本文根据垄青石晶体结构特点和有关热力学资料,建立了堇青石热膨胀系数的理论计算模式:半定量计算方法,α=α_MgO × 1/3 × 2/3;定量计算方法,α=ΔS/ΔT/2/(a × b).分别计算了堇青石、印度石的线热膨胀系数,半定量计算结果:α=3.31 × 10^-6℃^-1(堇青石、印度石);定量计算结果,a=1.54 × 10-6℃^-1(堇青石),α=0.85 × 10-6℃^-1(印度石),与实验测定结果(堇青石:α=2.3 × 10-6℃^-1,印度石:α=1.0 × 10^-6℃^-1)吻合。     

Numerical modelling of reinforced jointed rock masses I. Theory

The concept of reinforced multi-laminates has been developed and applied to the analysis of reinforced jointed rock masses. The discontinuities and reinforcements in the rock mass are assumed to occur in regular sets, with relatively close spacing within sets. The constitutive equations are established for an ‘equivalent material’, this being identical in its mechanical response to the reinforced jointed rock mass, consisting of its components, i.e. rock material, sets of discontinuities, and sets of reinforcements with associated sets of interfaces. An elasto-visco/plastic algorithm is used so that each component is described by its elastic, failure and flow properties together with its relative orientation. The constitutive equations for the ‘equivalent material’ can be applied to determine optimal reinforcement arrangements for problems of various levels of complexity. Several practical examples illustrating this are contained in a companion paper.     

中国现代浙江省动态变化及其发展趋势

用遥感,地图和野外考察研究等方法,首次揭示了我国现代沙漠动态变化规律和发展趋势,认为我国现代沙漠动态变化的总趋势是向草原化和绿洲化方向缓慢发展,其变化速度为４４５ｋｍ＾２／ａ,我国现代沙漠还在继续蔓延,但其扩大速度比较缓慢,约为３１０ｋｍ＾２／ａ。     

Gravito-electrodynamics and the structure of planetary ring systems

Recent spacecraft observations of the Saturnian and Jovian ring systems have highlighted a plethora of interesting new phenomena associated with those regions containing fine (micron and sub-micron sized) dust. Recognizing that these dust grains, by virtue of being immersed within the planetary magnetospheres, are electrostatically charged to the point that they experience comparable gravitational and electric forces, a new “gravito-electrodynamic” theory has been developed to describe their dynamics. This theory has been successful in explaining all these phenomena in a systematic way. In this review, the basic model and its range of validity are outlined, and its application to the Saturnian and Jovian ring systems are discussed.     

Croatia — “a small country for a great vacation”

Croatia is a country of tourism, and this is primarily due to its position by the warm Adriatic Sea, its varying and picturesque landscapes, its diverse and generally favorable climate for tourism, its rich Mediterranean and Central European cultural heritage and its proximity to the leading European consumer countries.In the international tourism market, Croatia presents itself with the slogan A Small Country for a Great Vacation, because its 4.8 million inhabitants and surface area of 56,538 km² place Croatia in the ranks of the world's smaller countries. Its significance is increased by an additional 33,200 km² of territorial waters, of which a large part is considered internal waters because of its location within the limits of a series of islands.The tourism offering of Croatia is very diverse, but its basis is formed by three differing and mutually complimentary regions, through their natural characteristics and cultural heritage: coastal, montane and Pannonian and peri-Pannonian Croatia. The total tourism offering of Croatia includes 900,000 beds, of which over one-fifth are in hotels or similar places, two-fifths are in private rooms and one-third in camps.The tradition of tourism in Croatia is over one hundred years old, and according to the number of foreign tourists it is ranked as the fifth country for tourism in southern Europe.