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经济发展对地质工作的需求因时空条件而异:在时间上演进是动态的,空间分布是不均衡的。1与时俱进的需求在经济发展的长时期中,对地质工作的总体需求处于相对稳定状态,与之相适应的地质工作在惯性作用下逐渐从需求驱动演变为供给驱动。到经济发展的不同阶段转换时期,对地质工作的需求结构发生变化,地质工作也要随着以新的主导需求取代原来的供给驱动,才能跟上经济发展新阶段的要求。在中国经济建设的不同时期和不同经济体制下,地质工作驱动力也会发生某种程度的变化。1.1中国地质工作的不同定位和需求1952年初,中央政府制定了国家“一五”计… 相似文献
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许世新 《矿物岩石地球化学通报》1989,(3)
宝玉石产品是特殊商品:宝玉石是一种个性很强的商品。钻石一向被认为是国际上价格最稳定的商品,实际上也在涨价。其他高档宝石和高档玉雕工艺品虽比不上钻石,但其保值作用也是显而易见的.中低档宝石市场在改革开放中随人们经济收入的增加将大幅度增长.这是不容忽视的国内需求市场。宝石产品中,经营高档宝石风险比较大,搞成本核算比较难。但是,由于比较少,不能 相似文献
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水是一种市场商品水的需求在空间和时间上的分配并不与自然界水的供给分配一致。这种分配上的差异需要空闻上靠输水建筑物调节,在时间上靠修建水库或者靠改变已有地表水或地下水的蓄水能力来调节。当这种调节可以经济地实现时,而且水质可以满足标准或可以经济地处理,则水就成为一种市场商品,成为与石油、天然 相似文献
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当前我国正处经济增速减缓的新常态,供给侧结构性改革应运而生。我国乃至世界的矿业更是处于发展的严冬之季,产能严重过剩,大宗商品价格持续走低。在当前形势下,我们要用新常态眼光看待矿业未来发展之路,因地制宜,着力加强供给侧改革,刻不容缓。 相似文献
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金融危机逆转市场需求,矿产品全线下跌
由于全球范围的金融危机加剧了投资者对于世界经济面临衰退的担忧,国际市场各类大宗商品价格10月再度呈现暴跌态势。除了供需基本面的担忧外,国际金融市场持续动荡使得投资者拥有了更加强烈的投资避险意识,这也是商品期货遭到疯狂抛售的重要原因。 相似文献
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张掖市经济用水与水资源社会性稀缺 总被引:1,自引:1,他引:0
在投入产出理论的基础上,建立了价值-实物混合型的水资源投入产出模型,以张掖市为例,从各产业部门的用水特征、各产业部门间的水关系以及地区商品贸易等方面系统地分析了造成水资源稀缺的社会经济原因.结果表明:尽管张掖水资源短缺,但它却拥有一个较强耗水能力的经济体系,其经济系统运行对水资源的需求几乎是其当前可用自然形态水的两倍,远远超出其水资源供给能力,对当地有限的水资源产生了巨大的压力;各产业部门的用水特征及部门间的投入产出关系决定了张掖市经济生产对水资源产生的压力难以通过贸易的形式转移到其它富水地区,然而其贸易结构却造成每年都有相当数量的水资源随商品以虚拟水的形式流向外地,并最终导致了张掖市水资源的社会性稀缺. 相似文献
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Gold has played an important role in the settlement and economics of the United States. Commercial production from 24 states totaled more than 420 million troy ounces (13,000 metric tons) from 1804 through 1995. There were, no doubt, early undocumented discoveries by Native Americans, but the first records are those from the mid-1600's in the east and from the 1770's in the west. Commercial production began in 1804 in North Carolina and spread among several Appalachian states in the 1820's and 1830's as placer deposits were discovered and exploited. After peaking in the 1830's and 1840's, Appalachian production began to decline as deposits were worked out and as miners moved westward in response to the news of the discoveries in California in 1848. Appalachian production virtually ceased with the Civil War while production from California and adjacent states remained at several millions of ounces per year. As the California Gold Rush waned, new discoveries brought the Rocky Mountain states, South Dakota, and Alaska into prominence. Local, state and total production responded to time of discovery, extent of placers, labor availability, technology, government mandates and, of course, the price of gold. By 1900, the major gold rushes had occurred and most of the major producing districts were defined; however, the fixed price of gold (since 1837) provided a decreasingly attractive incentive for more exploration and exploitation. The rise in the price of gold, during the Depression provided a powerful incentive to increase gold production, but one that was cut short by War Production Board Order L-208 which closed the gold mines in 1942. In the post-war period, the fixed price, combined with the prohibition of American gold ownership, again proved to be a disincentive and gold production dropped. The era of free gold price that began in 1968, followed by the permission for Americans to again own gold, brought new interest in gold with prices rising briefly in 1980 to US$850 per ounce and remaining above US$350 per ounce through 1995. This higher price, combined with the technology for bulk mining and processing of low grade ores, provided incentive for new exploration and exploitation. Consequently, gold production soared above 10 million ounces per year in the early 1990's with 65% coming from Nevada. There has been a general decrease in the grade of gold ores since the early 1900's and significant changes in the methods of recovery. Despite the decreasing grade, the reserves of recoverable gold have more than doubled since the early 1970's. 相似文献
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淤长型潮滩剖面形态演变模拟: 以江苏中部海岸为例 总被引:2,自引:0,他引:2
在泥质、砂质物质共存的淤长型潮滩, 其剖面的塑造受到潮流作用下堆积过程的控制.为探讨这种潮滩剖面的演变过程, 以江苏中部海岸为研究对象建立了大小潮周期性作用下的潮滩剖面演变模型, 模拟了潮滩均衡态剖面形态与初始坡度、潮差、沉积物供应量之间的关系及潮滩的持续淤长剖面.模拟结果表明: (1)淤长型潮滩剖面达到均衡态时的形态是上凸的, 且与初始形态无关; (2)在外源一定的条件下, 潮滩的宽度与潮差呈正相关; (3)外源物质供应越丰富, 潮滩宽度越大; (4)潮滩的冲淤状态由沉积物的供应量决定; (5)对大潮高潮位附近的无沉积带进行充填可实现对其长期持续淤长剖面的模拟; (6)有丰富沉积物来源的潮滩, 在调整至均衡态后仍持续向海淤长, 并在淤长过程中保持均衡态; (7)当在模型中输入有关江苏海岸的参数时, 模拟的潮滩宽度和坡度与江苏海岸的潮滩一致. 相似文献
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农用地转用生态补偿价格评估实证研究 总被引:2,自引:0,他引:2
农用地价值是农用地功能与效益的综合体现,但由于对农用地价值缺乏完整认识,导致我国农用地大量被低价转为建设用地。以吉林省四平市为例,从完全资源价格角度出发,探讨了农用地生态价值构成,并利用资源环境经济学的影子价格法、市场替代法、碳税法对其生态价值进行评估。 相似文献
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新世纪全球核电及铀生产态势分析 总被引:1,自引:0,他引:1
在分析目前世界铀的供需情况及核电生产现状的基础上,对新世纪铀的生产、库存、消耗、价格等进行了展望。铀作为军民两用战略物资,其生产、库存、消耗等,受世界政治、经济、军事局势的影响。本文对新世纪全球核电及铀生产态势进行分析,试图给人们提供一个对思考未来铀工业发展前景。 相似文献
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Pouria Behnoud far Mohammad Javad Ameri Mostafa Orooji 《Arabian Journal of Geosciences》2017,10(18):397
Geomechanical changes may occur in reservoirs due to production from reservoirs. Study of these changes has an important role in upcoming operations. Frictional equilibrium is one of the items that should be determined during the depletion as it may vary with respect to time. Pre-existing faults and fractures will slide in regions where there is no frictional equilibrium. Hence, it may be concluded that reduction in pore pressure can initiate the sliding of faults. Whereas, it is also possible that faults will not exist after a certain time as production recovers the equilibrium. Casing shearing or lost circulation may be occurred due to faulting. In reservoirs which depletion leads to frictional equilibrium, decrease of fractures and faults leads to some variations in permeability. Hence, predicting the effect of depletion on frictional equilibrium is required in dealing with casing shearing or lost circulation in drilling of new wells. In addition, permeability modeling will be more precise during the life of reservoirs. Estimation of necessary time to create or vanish faults is vital to be successful in production from wells or drilling new wells. Achieving or loosing of equilibrium mainly depends on in situ stresses and rate of production. Estimation of the in situ stresses at the initiation state of reservoir is the key to study the state of faults. The next step is to predict the effects of depletion on in situ stresses. Different models are suggested in which decrease of horizontal stresses is predicted as function of pore pressure variation. In these models, different assumptions are made such as simplifying the poroelastic theory, ignoring the passing time, and considering the geometry of reservoir. In this article, a new model is proposed based on theory of inclusions and boundary element method. This state-of-the-art model considers the geometry of reservoir. In addition, changes of in situ are obtained as a function of time to reach to a more precise model capable of applying during the reservoir life. Finally, the model is imposed on real cases. The effect of depletion on faults is studied in reservoirs of normal and strike-slip stress regimes, and conventional and proposed models are compared. For this aim, in the first step, mechanical earth models of these two reservoirs are built using logging and coring data. Stress polygon method and poroelastic horizontal strain model are used for strike-slip and normal regimes, respectively. In reservoir 1 which is in a strike-slip stress regime, a fault is distinguished in formation microimaging (FMI) log. For this reservoir, the required time to achieve to frictional equilibrium is calculated. In the reservoir 2, the potential depth of fault sliding is analyzed and required time for faulting in that depth is predicted. The predicted time for satisfaction of frictional equilibrium using the proposed model has a significant difference with the predicted time using the previous methods. In addition, the proposed model predicts that different parts of reservoir 2 are willing for faulting during depletion. The previous model determines only one point that faulting may happen. It is necessary to use this new model to consider different important factors such as geometry and time to gain more accurate predictions. 相似文献
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随着不确定性因素在商业交易中的越来越突出的影响,考虑价格随机波动的动态定价研究成为管理经济学的重要课题。作者把随机误差所带来的不确定因素引入制造商主导定价数学模型,引入零售价格的期望、方差和转移价格的期望,将不完全信息博弈转化为完全信息博弈,并结合最优生产和存储模型,运用泛函极值方法解决供方先动需方后动的转移价格定价问题。获得了最优转移价格的预期龙的结构模型和预期价格与价格波动的比例关系,进而指出掌握定价主动权的制造商一方掌控了大部分利润。 相似文献
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Analyzing regional economic impact and resilience: a case study on electricity outages caused by the 2008 snowstorms in southern China 总被引:2,自引:1,他引:1
When we think about the loss caused by natural disasters, we generally think about the direct economic loss. Although the direct economic loss is often obvious, the subsequent indirect economic loss can also be quite substantial. This research is a case study about the indirect economic impact of the Hunan electricity disruptions resulting from the 2008 snowstorms in southern China. Utilizing the computable general equilibrium model, this study shows that the indirect economic loss in Hunan Province resulting from electricity supply disruptions is estimated at USD 372 million over a 3-month recovery period. We also compare our results with other studies that use input–output models and discuss how the total regional economic resilience can mitigate economic losses through market substitutions and price changes. 相似文献
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后危机时代矿产品价格趋势分析 总被引:17,自引:13,他引:4
通过对近50年来石油、铜、铝、镍价格变化趋势分析, 总结了矿产品价格长周期变化规律: 不变价格呈周期性下降趋势, 现价价格呈台阶状上升趋势。铜、铝、镍不变价格的绝对下降反映了人类技术进步带来生产效率的不断提高, 而石油不变价格的上升反映了资源稀缺程度对石油价格的重要影响; 由资源稀缺性决定的资源性商品的生产效率难以与其他商品生产效率同步提高, 必然以现价价格阶段性上涨实现价格平衡。结合矿产品成本、供需趋势和市场体系分析, 判断后金融危机时代矿产品价格平台为: 石油60~80美元/桶、铜3500美元/吨、铝2100美元/吨、镍14000美元/吨。 相似文献