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1.
研究了Tb~(3+)、Dy~(3+)-乙酰丙酮(AA)-三正辛基氧化膦(TOPO)-Triton X-100体系的荧光特性,利用时间分辨-窗口技术实现了Tb和Dy的同时测定,用于合成样品和氧化钇试剂中痕量Tb、Dy的测定,结果良好。  相似文献   

2.
所有硫酸盐类中的SO_4~(2-)本征的发光中心(LC)出现在360nm,但在含大量杂质的硫酸盐中是不存在的。在硬石膏的发光光谱中已观测到三个非等效的Gd~(3+)LC,在天青石中确立了Gd~(3+)、Ce~(3+)和O_2LC。硫酸盐中光致发光(PL)带分配如下:Ca和Ba的硫酸盐中,该带在460nm,它与Eu~(2+)有关(同样可能与Al~(3+)或施主—受主对相联系);520和590nm的带与VO_4、MoO_4和TiO_4置换SO_4有关;660nm谱带由Ti引起,在620nmX射线的发光(XL)带由Ag引起。  相似文献   

3.
独居石、磷钇矿显微阴极射线发光研究   总被引:5,自引:0,他引:5  
独居石、磷钇矿的显微阴极射线发光观察表明,独居石的发光颜色为酱红色,发光较弱,发光强度分布不均匀,受杂质Fe_O_3影响明显。其中有相当数量零星分布的绿色强发光点。发光谱测定表明,这些绿色发光点来自Tb~(3+)、Dy~(3+)的非均匀分布。而独居石的基本发光色来自Sm~(3+)、Eu~(3+)和Tm~(3+)跃迁线。磷钇矿发光色为豆绿色,发光强度大,分布均匀,不受杂质Fe_2O_3影响。两者发光机理也不同,独居石发光直接来自Ce~(3+)的f-d跃迁和它对某些离子的能量传递,而磷钇矿则以[PO_4]~(4-)阴离子团为敏化中心,实现能量向Dy~(3+)等离子传输。  相似文献   

4.
云南宝丰寺岩体地处扬子陆块西缘金沙江-红河断裂与程海-宾川断裂夹持部位,属于金沙江-红河富碱斑岩带组成部分,由细晶黑云母花岗斑岩(FCBGP)和粗晶花岗斑岩(CGGP)组成。通过对宝丰寺岩体开展的锆石Ti温度、锆石Ce~(4+)/Ce~(3+)值和δEu和δCe值研究结果表明:两类岩石锆石Ti温度相差不大(FCBGP为618.55℃—792.75℃,均值为692.42℃;CGGP为560.35℃~820.41℃,均值为714.13℃),与S型花岗岩浆形成温度相似,反映宝丰寺岩体属S型花岗岩;锆石Ce~(4+)/Ce~(3+)值、δEu和δCe值总体较高(FCBGP的Ce~(4+)/Ce~(3+)值、δEu和δCe分别为24.51~1190.06、0.32~0.49和10.17~1231.19,均值分别为390.36、0.42和264.29;CGGP的Ce~(4+)/Ce~(3+)值、δEu和δCe分别为50.13~494.56、0.44~0.58和24.87~262.76,均值分别为232.98、0.49和141.82),与金沙江-红河富碱斑岩带含矿岩体特征值类似,表明宝丰寺岩体形成于高氧逸度环境,有利于岩浆体系中的成矿金属元素保留至岩浆分异演化的晚阶段,有利于形成斑岩型矿床。  相似文献   

5.
郦楷元  华萍 《岩矿测试》1983,(4):314-315
自1975年Ruzicka与Hansen提出“流动注入分析法(Flow Injection Analysis)简称FIA)以来,国外进展较快。1979年在荷兰召开了这一技术的专门会议。而且在理论上也逐趋成熟。我们就地球化学工作中对碘有较高的要求,开展了一些工作,效果良好。 方法基于反应 2Ce~(4+)+As~(3+)→2Ce~(3+)+As~(6+) 橙红色 无色但在常温下进行缓慢,而碘离子可以催化这一反应。陈四箴对这一反应也有过论述。有人将这一反应应用于FIA技术,并最终测定出0.15纳克的碘。我们就该体系应用于FIA技术借光度法测定绝对含碘0.63纳克,检测限达8ppb(峰高0.1v),使用样品溶液63微升。  相似文献   

6.
波龙、多不杂斑岩铜金矿床是青藏高原中部发现的两个大型斑岩铜金矿床。对波龙、多不杂斑岩铜金矿床含矿花岗闪长斑岩和不含矿花岗闪长斑岩的锆石Ce~(4+)/Ce~(3+)比值以及氧逸度等特征进行研究,并且通过计算得到了3个含矿花岗闪长斑岩的锆石Ce~(4+)/Ce~(3+)比值分别为536.03,492.18,454.02;1个不含矿的花岗闪长斑岩的锆石Ce~(4+)/Ce~(3+)比值为0.67。说明波龙、多不杂斑岩矿床中与成矿相关的岩体具有相对更高的氧化状态。对比西藏冈底斯成矿带中的斑岩矿床、云南中甸岛弧成矿带中的烂泥塘斑岩铜矿床、金沙江-红河成矿带中的马厂箐、铜厂铜钼矿以及玉龙成矿带铜钼矿床岩体的锆石Ce~(4+)/Ce~(3+)比值,发现含矿岩体锆石Ce~(4+)/Ce~(3+)比值一般250。结合波龙、多不杂矿床的锆石Ce~(4+)/Ce~(3+)的计算结果发现Ce~(4+)/Ce~(3+)基本300,因此将锆石Ce~(4+)/Ce~(3+)300作为波龙、多不杂矿床斑岩成矿的一个地球化学标志。此外,通过(Ce/Ce~*)_D锆石氧逸度计和(X_(Ce~(4+))~(melt)/X_(Ce~(3+))~(melt))锆石氧逸度计计算得到的波龙、多不杂矿床含矿花岗闪长斑岩体的氧逸度(log(f_(O_2)))分别位于MH(磁铁矿-赤铁矿)缓冲带和FMQ(铁橄榄石-磁铁矿-石英)缓冲带之上,平均值为ΔMH+3.24和ΔFMQ+1.78,前人研究发现多不杂含矿石英斑岩的氧化状态较高,平均ΔNNO+2.4,含矿斑岩体的形成具有较高的氧逸度条件,说明高氧逸度更有利于多龙矿集区斑岩型铜矿成矿。  相似文献   

7.
利用干馏后的油页岩灰渣,湿法提取氧化铝作为发光材料基质,经采用高温固相法合成 CaAl2O4 : Eu3 + ,R + ( R = Li,Na,K,Rb) 荧光粉。最佳合成条件为: 烧结温度1 200 ℃,烧结时间3 h,助熔剂加入量3 wt%,激活离子配比3 mol%; 实验发现辅助激活离子为Li + 时,CaAl2O4 : Eu3 + , Li + 的发光强度最强。样品荧光光谱分析结果表明,发射光谱在615 nm 处出现强谱峰,归属为Eu3 + 的5D0→7F2 跃迁辐射。  相似文献   

8.
对 3个不同地区的硅灰石类粉尘做了XRF分析及其与溶菌酶 (Lys)的反应实验 ,结果显示Lys与样品中的活性物质进行了反应。模拟样品中元素离子与Lys反应的UV_Vis和荧光光谱分析表明 ,37℃下Lys与样品中的元素离子SiO2 -3 作用最明显 ,表现在紫外区吸收峰红移 10nm ,吸光度增大 ,荧光区λem4 4 0nm处荧光强度增强 ,荧光峰红移 2 0nm。同时 ,对其反应机理和结合位点进行了探讨  相似文献   

9.
对3个不同地区的硅灰石类粉尘做了XRF分析及其与溶菌酶(Lys)的反应实验,结果显示Lys与样品中的活性物质进行了反应.模拟样品中元素离子与Lys反应的UV-Vis和荧光光谱分析表明,37℃下Lys与样品中的元素离子(SiO23-)作用最明显,表现在紫外区吸收峰红移10 nm,吸光度增大,荧光区λem 440 nm处荧光强度增强,荧光峰红移20 nm.同时,对其反应机理和结合位点进行了探讨.  相似文献   

10.
从光致发光光谱角度探讨了海南蓬莱蓝宝石的呈色机理.结果发现:与蓝宝石吸收光谱的500~700 nm吸收宽带相比,在500~720 nm发光波段内存在566.8 nm锐峰、600 nm左右肩峰和Cr~(3+)的694.2 nm特征峰.600 nm肩峰与其吸收峰镜像对称,566.8 nm处锐峰的产生原因复杂.600 nm肩峰可能与Fe~(2+)-Fe~(2+)离子对的电子跃迁有关;566.8 nm锐峰因532 nm激光激发Fe~(2+)-Ti~(4+)或Fe~(2+)-Fe~(3+)间的电荷迁移带,通过晶格造成Si~(4+)、Mg~(2+)等微量杂质离子敏化而产生.光致发光谱中呈现更多谱峰,能呈现离子跃迁时不同离子间发生的相互作用,为500~700 nm吸收宽带由不同致色机制的叠加给出了直接证明,是一种能全面地研究宝石矿物中致色元素能级结构的有效方法.  相似文献   

11.
Most sulfide-rich magmatic Ni-Cu-(PGE) deposits form in dynamic magmatic systems by partial melting S-bearing wall rocks with variable degrees of assimilation of miscible silicate and volatile components, and generation of barren to weakly-mineralized immiscible Fe sulfide xenomelts into which Ni-Cu-Co-PGE partition from the magma. Some exceptionally-thick magmatic Cr deposits may form by partial melting oxide-bearing wall rocks with variable degrees of assimilation of the miscible silicate and volatile components, and generation of barren Fe ± Ti oxide xenocrysts into which Cr-Mg-V ± Ti partition from the magma. The products of these processes are variably preserved as skarns, residues, xenoliths, xenocrysts, xenomelts, and xenovolatiles, which play important to critical roles in ore genesis, transport, localization, and/or modification. Incorporation of barren xenoliths/autoliths may induce small amounts of sulfide/chromite to segregate, but incorporation of sulfide xenomelts or oxide xenocrysts with dynamic upgrading of metal tenors (PGE > Cu > Ni > Co and Cr > V > Ti, respectively) is required to make significant ore deposits. Silicate xenomelts are only rarely preserved, but will be variably depleted in chalcophile and ferrous metals. Less dense felsic xenoliths may aid upward sulfide transport by increasing the effective viscosity and decreasing the bulk density of the magma. Denser mafic or metamorphosed xenoliths may also increase the effective viscosity of the magma, but may aid downward sulfide transport by increasing the bulk density of the magma. Sulfide wets olivine, so olivine xenocrysts may act as filter beds to collect advected finely dispersed sulfide droplets, but other silicates and xenoliths may not be wetted by sulfides. Xenovolatiles may retard settling of – or in some cases float – dense sulfide droplets. Reactions of sulfide melts with felsic country rocks may generate Fe-rich skarns that may allow sulfide melts to fractionate to more extreme Cu-Ni-rich compositions. Xenoliths, xenocrysts, xenomelts, and xenovolatiles are more likely to be preserved in cooler basaltic magmas than in hotter komatiitic magmas, and are more likely to be preserved in less dynamic (less turbulent) systems/domain/phases than in more dynamic (more turbulent) systems/domains/phases. Massive to semi-massive Ni-Cu-PGE and Cr mineralization and xenoliths are often localized within footwall embayments, dilations/jogs in dikes, throats of magma conduits, and the horizontal segments of dike-chonolith and dike-sill complexes, which represent fluid dynamic traps for both ascending and descending sulfides/oxides. If skarns, residues, xenoliths, xenocrysts, xenomelts, and/or xenovolatiles are present, they provide important constraints on ore genesis and they are valuable exploration indicators, but they must be included in elemental and isotopic mass balance calculations.  相似文献   

12.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

13.
This article advances critical geographies of youth through examining the spatiality implicit in the imagined futures of young women in rural India. Geographers and other scholars of youth have begun to pay more attention to the interplay between young people’s past, present, and imagined futures. Within this emerging body of scholarship the role of the family and peer group in influencing young people’s orientations toward the future remain underexamined. Drawing on eleven months of ethnographic fieldwork, my research focuses on a first generation of college-going young women from socioeconomically marginalized backgrounds in India’s westernmost state of Gujarat. I draw on the “possible selves” theoretical construct in order to deploy a flexible conceptual framework that links imagined post-educational trajectories with motivation to act in the present. In tracing the physical movement of these young women as they navigate and complete college, my analysis highlights the ways in which particular kinds of spaces and spatial arrangements facilitate and limit intra- and inter-generational contact, and the extent to which this affects young women’s conceptions of the future. I conclude by considering the wider implications of my research for ongoing debates surrounding youth transitions, relational geographies of age, and education in the Global South.  相似文献   

14.
The contents of As, Cd, Cu, Cr, Mg, Mn, Ni, Pb and Zn have been determined in sediment and water samples from Valle de las Garzas estuary and Port Manzanillo (Colima, Mexico) using ICP-AES. The concentrations of these elements were used for a comparative study to determine the distribution of heavy metals and to evaluate which elements reflect natural or anthropogenic backgrounds. For this purpose, seven sampling points were selected: Four of them correspond to the lagoon, and three were situated in the port. Statistical analysis of the mineral content was assessed. Initially, data comparison was assessed by statistical tests for each variable. Principal component analysis was then applied considering the influence of all variables at the same time by obtaining the distribution of samples according to their scores in the principal component space. In this way, four studies were carried out: (1) study of sediments collected during the dry season; (2) study of sediments collected during the rainy season; (3) comparative study between sediments from rainy and dry season; and (4) study of water composition collected during rainy season. From the results of the performed analyses, it can be concluded that metals distribution pattern reflected natural and anthropogenic backgrounds (e.g., sediments from the lagoon, situated at the beginning of the rain channel, presented high contents of Zn and Cu, perhaps related to anthropogenic activities or the influence of igneous sediments).  相似文献   

15.
Partition coefficients of Hf,Zr, and REE between zircon,apatite, and liquid   总被引:25,自引:2,他引:25  
Concentration ratios of Hf, Zr, and REE between zircon, apatite, and liquid were determined for three igneous compositions: two andesites and a diorite. The concentration ratios of these elements between zircon and corresponding liquid can approximate the partition coefficient. Although the concentration ratios between apatite and andesite groundmass can be considered as partition coefficients, those for the apatite in the diorite may deviate from the partition coefficients. The HREE partition coefficients between zircon and liquid are very large (100 for Er to 500 for Lu), and the Hf partition coefficient is even larger. The REE partition coefficients between apatite and liquid are convex upward, and large (D=10–100), whereas the Hf and Zr partition coefficients are less than 1. The large differences between partition coefficients of Lu and Hf for zircon-liquid and for apatite-liquid are confirmed. These partition coefficients are useful for petrogenetic models involving zircon and apatite.  相似文献   

16.
17.
《Chemical Geology》2007,236(1-2):13-26
We examined the coprecipitation behavior of Ti, Mo, Sn and Sb in Ca–Al–Mg fluorides under two different fluoride forming conditions: at < 70 °C in an ultrasonic bath (denoted as the ultrasonic method) and at 245 °C using a Teflon bomb (denoted as the bomb method). In the ultrasonic method, small amounts of Ti, Mo and Sn coprecipitation were observed with 100% Ca and 100% Mg fluorides. No coprecipitation of Ti, Mo, Sn and Sb in Ca–Al–Mg fluorides occurred when the sample was decomposed by the bomb method except for 100% Ca fluoride. Based on our coprecipitation observations, we have developed a simultaneous determination method for B, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta by Q-pole type ICP-MS (ICP-QMS) and sector field type ICP-MS (ICP-SFMS). 9–50 mg of samples with Zr–Mo–Sn–Sb–Hf spikes were decomposed by HF using the bomb method and the ultrasonic method with B spike. The sample was then evaporated and re-dissolved into 0.5 mol l 1 HF, followed by the removal of fluorides by centrifuging. B, Zr, Mo, Sn, Sb and Hf were measured by ID method. Nb and Ta were measured by the ID-internal standardization method, based on Nb/Mo and Ta/Mo ratios using ICP-QMS, for which pseudo-FI was developed and applied. When 100% recovery yields of Zr and Hf are expected, Nb/Zr and Ta/Hf ratios may also be used. Ti was determined by the ID-internal standardization method, based on the Ti/Nb ratio from ICP-SFMS. Only 0.053 ml sample solution was required for measurement of all 9 elements. Dilution factors of ≤ 340 were aspirated without matrix effects. To demonstrate the applicability of our method, 4 carbonaceous chondrites (Ivuna, Orgueil, Cold Bokkeveld and Allende) as well as GSJ and USGS silicate reference materials of basalts, andesites and peridotites were analyzed. Our analytical results are consistent with previous studies, and the mean reproducibility of each element is 1.0–4.6% for basalts and andesites, and 6.7–11% for peridotites except for TiO2.  相似文献   

18.
Models have become so fashionable that many scientists and engineers cannot imagine working without them. The predominant use of computer codes to execute model calculations has blurred the distinction between code and model. The recent controversy regarding model validation has brought into question what we mean by a ‘model’ and by ‘validation.’ It has become apparent that the usual meaning of validation may be common in engineering practice and seems useful in legal practice but it is contrary to scientific practice and brings into question our understanding of science and how it can best be applied to such problems as hazardous waste characterization, remediation, and aqueous geochemistry in general. This review summarizes arguments against using the phrase model validation and examines efforts to validate models for high-level radioactive waste management and for permitting and monitoring open-pit mines. Part of the controversy comes from a misunderstanding of ‘prediction’ and the need to distinguish logical from temporal prediction. Another problem stems from the difference in the engineering approach contrasted with the scientific approach. The reductionist influence on the way we approach environmental investigations also limits our ability to model the interconnected nature of reality. Guidelines are proposed to improve our perceptions and proper utilization of models. Use of the word ‘validation’ is strongly discouraged when discussing model reliability.  相似文献   

19.
Pools,riffles, and channelization   总被引:2,自引:0,他引:2  
The addition of regularly spaced deeps (pools) and shallows (riffles) that provide a variety of flow conditions, areal sorting of stream-bed material, cover for wildlife, and a positive aesthetic experience, may be desirable in many channel projects. Such designs will reduce adverse environmental impacts of stream channel modifications. Analysis of variance for pool-to-pool spacing data suggests that there is no significant difference with respect to channel width between pools that form in natural streams and those in streams affected by a variety of human uses. Short of channelization, which changes the channel width, pools and riffles, within limits, are not particularly sensitive to environmental stress. Experiments in Gum Branch near Charlotte, North Carolina, support the hypothesis that channel form and process evolve in harmony and that manipulation of cross-channel morphology can influence the development of desired channel processes. Planned manipulation of its channel form induced Gum Branch to develop as desired. Morphologic stability consisting of incipient point bars, pools, and riffles was maintained over a period of high magnitude flood events, only to be degraded later by a wave of sediment derived from upstream construction and stream-bank failures. Thus, environmentally desirable channel morphology in urban streams cannot remain stable if changes in the sediment load or storm-water runoff exceed the limits of the stream's ability to make internal adjustments while maintaining morphologic stability.  相似文献   

20.
Materials and energy are the interdependent feedstocks of economic systems, and thermodynamics is their moderator. It costs energy to transform the dispersed minerals of Earth's crust into ordered materials and structures. And it costs materials to collect and focus the energy to perform work — be it from solar, fossil fuel, nuclear, or other sources. The greater the dispersal of minerals sought, the more energy is required to collect them into ordered states.But available energy can be used once only. And the ordered materials of industrial economies become disordered with time. They may be partially reordered and recycled, but only at further costs in energy. Available energy everywhere degrades to bound states and order to disorder — for though entropy may be juggled it always increases. Yet industry is utterly dependent on low entropy states of matter and energy, while decreasing grades of ore require ever higher inputs of energy to convert them to metals, with ever increasing growth both of entropy and environmental hazard.Except as we may prize a thing for its intrinsic qualities — beauty, leisure, love, or gold — low-entropy is the only thing of real value. It is worth whatever the market will bear, and it becomes more valuable as entropy increases. It would be foolish of suppliers to sell it more cheaply or in larger amounts than their own enjoyment of life requires, whatever form it may take. For this reason, and because of physical constraints on the availability of all low-entropy states, the recent energy crises is only the first of a sequence of crises to be expected in energy and materials as long as current trends continue.The apportioning of low-entropy states in a modern industrial society is achieved more or less according to the theory of competitive markets. But the rational powers of this theory suffer as the world grows increasingly polarized into rich, over-industrialized nations with diminishing resource bases and poor, supplier nations with little industry. The theory also discounts posterity, the more so as population density and percapita rates of consumption continue to grow. A new social, economic, and ecologic norm that leads to population control, conservation, and an apportionment of low-entropy states across the generations is needed to assure to posterity the options that properly belong to it as an important but voiceless constituency of the collectivity we call mankind.
Zusammenfassung Rohstoffe und Energie sind die Grundlagen unseres ökonomischen Systems, das von den Gesetzen der Thermodynamik bestimmt wird. Es kostet Energie, um die auf der Erde verteilten Rohstoffe diesem System zuzuführen. Andererseits braucht man Rohstoffe, um die Energie nutzbar zu machen.Die verfügbare Energie kann nur einmal genutzt werden und das Material verbraucht sich. Verbrauchtes Material kann teilweise zur weiteren Nutzung zurückgeführt werden, das kostet wiederum Energie. Die verfügbare Energie nimmt überall ab, und einmal geschaffene Ordnung gerät wieder in Unordnung — das heißt, die Entropie des Systems nimmt ständig zu. Die Industrie ist jedoch abhängig von einem niedrigen Entropiezustand sowohl der Materie als auch der Energie.Je ärmer die Erze sind, um so höher wird die Energie sein, um sie in Metalle umzuwandeln, wobei die Entropie und die Belastung der Umwelt ständig zunimmt.Außer den Dingen, die wir wegen höherer ideeller Werte schätzen, ist eine niedrige Entropie der einzige realistische Wertmaßstab, und der wirkliche Wertzuwachs ist nur an einer höheren Entropie zu messen. Es ist unverantwortlich, Dinge, die eine höhere Entropie bedingen, billiger zu verkaufen oder in größerer Menge zu erzeugen, als unbedingt notwendig ist. Da wir dies heute in unserem Handeln nicht berücksichtigen, ist die derzeitige Energiekrise nur der Anfang einer Folge von Krisen, die Energie und Rohstoffe betreffen, solange wir nicht umdenken.Die Verteilung von niedriger Entropie in einer modernen Industriegesellschaft wird mehr oder weniger nach dem Prinzip der konkurrierenden Märkte erreicht. Das selbstregulierende System gerät jedoch mit zunehmender Polarisierung in reiche Industrienationen mit abnehmenden Ressourcen und armen Nationen mit geringer Industrialisierung in Unordnung. Dieses Prinzip berücksichtigt auch nicht die Nachwelt, vor allem wenn die Bevölkerungsdichte stetig zunimmt und die Konsumbedürfnisse anwachsen. Es sind neue soziale, ökonomische und ökologische Normen notwendig, die zur Populationskontrolle, zur Erhaltung der Umwelt und zu einem Zustand niedriger Entropie für zukünftige Generationen führen. Die nach uns kommenden Menschen haben ein Anrecht darauf.

Résumé Matériaux et énergie sont les sources des systèmes économiques et sont régis par les lois de la thermodynamique. Il faut de l'énergie pour transformer les ressources minérales dispersées dans la croûte terrestre en matériaux et structures ordonnancées. Et il faut des matériaux pour receuillir et concentrer l'énergie, qu'elle soit solaire ou atomique, ou provienne de combustibles fossiles ou d'autres sources. Plus les minéraux recherchés sont dispersés et plus est côuteuse l'énergie pour leur donner une ordonnance.Or l'énergie disponsible ne peut être utilisée qu'une seule fois. Et les matériaux ordonnancés des économies industrielles se dégradent avec le temps. Ils peuvent être remis partiellement en état et recyclés, mais pour cela il faut de nouveau de l'énergie. Partout l'énergie disponible se dégrade et l'ordre devient désordre; -malgré toutes les jongleries possibles l'entropie augmente toujours.L'industrie dépend clairement d'états de basse entropie tant en ce qui concerne les matériaux que l'énergie, tandis que plus pauvres sont les minerais, plus; élevée est l'énergie à mettre en jeu pour en extraire les métaux, avec toujours augmentation à la fois de l'entropie et de la degradation des milieux.A l'exception de ce que nous apprécions pour leur valeur intrinsèque — la beauté, le loisir, l'amour ou l'or — la basse entropie est la seule chose de réelle valeur. Son prix est réglé par le marché, et sa valeur augmente au fur et à mesure que l'entropie s'accroît. Ceux qui en disposent seraient insensés de la vendre à bas prix ou en quantité supérieure à ce qu'exige leur propre niveau de vie. Pour cette raison, et à cause des contraintes physiques liées à la disponibilité en états de basse entropie, la récente crise d'énergie n'est, en ce qui concerne les matières premières et l'énergie, que la première d'une série de crises auxquelles il faut s'attendre aussi longtemps que se poursoit la marche actuelle des étènements.Dans les sociétés industrielles modernes, les approvisionnement en basse entropie s'effectuent plus ou moins conformément à la théorie de la concurrence des marchés. Cependant la rationalité de cette théorie se ressent de l'accentuation croissante de la polarisation, à l'échelle du monde, en nations riches, surindustrialisées, à ressources de base décroissantes, et en nations pauvres, sous-industrialisées, mais fournisseurs de resources-naturelles. De plus cette théorie ne tient pas compte de notre postérité, et ce, en face d'une densité de population et d'un taux de la consommation par tête d'habitant en augmentation continue.Nous avons donc besoin de nouvelles normes sociales, économiques et écologiques qui conduisent au contrôle de la population, à la conservation et à la répartition des états de basse entropie à travers les générations pour assurer à notre postérité les options qui leur riviennent de droit comme une constituante importante, mais encore muette, de la collectivité que nous appelons l'Humanité.

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Dedicated with appreciation to Nicholas Georgescu-Roegen, distinguished economist, realist among cornucopians  相似文献   

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