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Auswahl der wissenschaftlichen Literatur zum Thema „Minerals Depletion“
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Zeitschriftenartikel zum Thema "Minerals Depletion"
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Sun, Bo Xue, Zuo Ren Nie, Yu Liu, Zhi Hong Wang und Xian Zheng Gong. „Exergy-Based Model of the Depletion of Mineral Resources“. Materials Science Forum 650 (Mai 2010): 1–8. http://dx.doi.org/10.4028/www.scientific.net/msf.650.1.
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The primary problem of eco-materials is how to judge whether a material is environmentally friendly or not, and the method of life cycle assessment is usually used to evaluate it. The depletion of mineral resources is a very important indicator of LCA, but its characterization is still filled with dispute. At present, the most commonly used method is CML, which is put forward by Leiden University, and its core idea is that using the ratio of exploitation amount and reserves of mineral resources as the degree of scarcity. Although being accepted by most of the scholars at work on LCA, CML doesn’t grasp the essence of the depletion of mineral resources. Recently, a new assessment method, injecting new ideas to the conventional life cycle assessment, combines exergy with LCA is arising, which can be used to solve some specific problems of LCA especially the depletion of mineral resources. In this paper, two results of elements’ exergy calculated by Rivero and Szargut respectively are compared, and the exergy of some natural minerals, which can be used in LCA and other minerals-related research, is calculated based on the data of Chinese mineral resources.
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Fisher, Beth A., Kyungsoo Yoo, Anthony K. Aufdenkampe, Edward A. Nater, Joshua M. Feinberg und Jonathan E. Nyquist. „Mineral surface area in deep weathering profiles reveals the interrelationship of iron oxidation and silicate weathering“. Earth Surface Dynamics 11, Nr. 1 (31.01.2023): 51–69. http://dx.doi.org/10.5194/esurf-11-51-2023.
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Abstract. Mineral specific surface area (SSA) increases as primary minerals weather and restructure into secondary phyllosilicate, oxide, and oxyhydroxide minerals. SSA is a measurable property that captures cumulative effects of many physical and chemical weathering processes in a single measurement and has meaningful implications for many soil processes, including water-holding capacity and nutrient availability. Here we report our measurements of SSA and mineralogy of two 21 m deep SSA profiles at two landscape positions, in which the emergence of a very small mass percent (<0.1 %) of secondary oxide generated 36 %–81 % of the total SSA in both drill cores. The SSA transition occurred near 3 m at both locations and did not coincide with the boundary of soil to weathered rock. The 3 m boundary in each weathering profile coincides with the depth extent of secondary iron oxide minerals and secondary phyllosilicates. Although elemental depletions in both profiles extend to 7 and 10 m depth, the mineralogical changes did not result in SSA increase until 3 m depth. The emergence of secondary oxide minerals at 3 m suggests that this boundary may be the depth extent of oxidation weathering reactions. Our results suggest that oxidation weathering reactions may be the primary limitation in the coevolution of both secondary silicate and secondary oxide minerals. We value element depletion profiles to understand weathering, but our finding of nested weathering fronts driven by different chemical processes (e.g., oxidation to 3 m and acid dissolution to 10 m) warrants the recognition that element depletion profiles are not able to identify the full set of processes that occur in weathering profiles.
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Weitzman, M. L. „Pricing the Limits to Growth from Minerals Depletion“. Quarterly Journal of Economics 114, Nr. 2 (01.05.1999): 691–706. http://dx.doi.org/10.1162/003355399556025.
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BLACK, J. R., C. B. AMMERMAN, P. R. HENRY und R. C. LITTELL. „INFLUENCE OF DIETARY MANGANESE ON TISSUE TRACE MINERAL ACCUMULATION AND DEPLETION IN SHEEP“. Canadian Journal of Animal Science 65, Nr. 3 (01.09.1985): 653–58. http://dx.doi.org/10.4141/cjas85-077.
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An experiment was conducted to investigate tissue trace mineral accumulation and depletion in sheep fed high dietary Mn in the form of reagent grade MnO. During the pre-trial phase, 32 wethers, 56 kg initially, were group-fed the basal corn-soybean meal diet (36 mg/kg Mn) for 8 days at which time eight sheep were slaughtered and tissues were taken to represent controls. For the remaining sheep, the experiment was divided into two phases of 6 wk and 12 wk; during the first phase (accumulation), the diet contained 8000 mg/kg supplemental Mn and during the second phase (depletion) the diet was the unsupplemented basal. Sheep were slaughtered at various intervals during both phases and tissue samples were taken. Manganese increased in all tissues measured during accumulation but decreased rapidly during the depletion phase. In general, liver and kidney Zn and Cu increased during the accumulation phase but tissue Fe decreased during this phase. MnO appeared to be a relatively safe supplemental source of Mn for sheep. Key words: Manganese, trace minerals, tissue minerals, sheep
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Çolak, Ayşenur, Bertrand Laratte, Birol Elevli und Semra Çoruh. „Abiotic Depletion of Boron: An Update Characterization Factors for CML 2002 and ReCiPe“. Minerals 12, Nr. 4 (31.03.2022): 435. http://dx.doi.org/10.3390/min12040435.
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The risk of resource depletion for future generations of humanity is often cited as an important issue. The choice of impact categories and characterization models for resource extraction in LCA is no more precise than other impact categories and models. This means that more discussion is needed on the use of resources. In this article, the potential depletion of Boron and Boron minerals (Colemanite, Ulexite, Tincal) are studied. These minerals have a big role for the world and for Turkey; however, this resource is limited. Using the life cycle assessment methodology, one can estimate the resource depletion through the indicator “abiotic resource depletion”. Several models can evaluate this indicator, but the most used models are ReCiPe and CML (that is the previous attempt of ReCiPe) methods. Here, we estimated the damage that is done to natural resource scarcity. The values that are calculated by these two methods were compared to identify the potential evolution of the model and to observe the gap between these two models. The ReCiPe method refers to the average amount of extra ore that is produced in the future to extract 1 kg of boron ore or boron minerals resource. On the other hand, The CML method depends on the final reserve amount in terms of depletion. The results show no depletion shortly for boron ore and boron minerals. Correlation coefficients were calculated in the ReCiPe method, and ‘high uncertainty’ was estimated since R2 < 0.8. This research highlights the fact that there is the necessity to propose different impact factors for the various minerals and not only for boron (that is done today).
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Zhang, Yan Jiao, Feng Gao und Zhi Hong Wang. „Updated Resource Depletion Characterization Factors for Life Cycle Assessment-Case Studies on Iron and Steel Production in China“. Materials Science Forum 847 (März 2016): 358–65. http://dx.doi.org/10.4028/www.scientific.net/msf.847.358.
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In this study, the CML model for resource depletion was updated based on the current status of the mineral resources and the characteristics of relevant statistics in China; and the characterization factors of resource depletion were determined for the majority of natural minerals which are most used in materials industry. Besides, case studies on iron and steel production (BF-BOF and EAF process) were carried out to demonstrate the valid of the modified and localized resource depletion model. The results show that in terms of category, the development of Chinese steel industry is mainly based on the depletion of the natural iron ore and fluorite. The results also show that for BF-BOF process, abiotic resource depletion potential (ADP) in 2012 is 5.26 times of that in 2004; and for the EAF process, ADP in 2012 is 23.6 times of that in 2004. Therefore, the information of ADP needs to be updated at intervals of time.
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Oziegbe, E. J., V. O. Olarewaju und O. O. Ocan. „MINERAL CHEMISTRY AND GEOCHEMISTRY OF HYPERSTHENE-BEARING DIORITE FROM ERUSU AKOKO, SOUTHWESTERN NIGERIA“. Malaysian Journal of Geosciences 4, Nr. 1 (07.02.2020): 13–18. http://dx.doi.org/10.26480/mjg.01.2020.13.18.
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Samples of mafic intrusive rock were analyzed for their mineralogical and chemical properties. The textural relationship was studied using the petrographic microscope, elemental composition of minerals was determined using the Electron Microprobe and the whole rock chemical analysis was done using the XRF and ICP-MS. The following minerals were observed in order of abundance; pyroxene, amphibole, plagioclase, biotite, opaque minerals, quartz and chlorite, with apatite and zircon occurring as accessory mineral. Two types of pyroxenes were observed; orthopyroxene (hypersthene) and clinopyroxene. Texturally, amphiboles have inclusions of plagioclase and pyroxene. The plagioclase has undergone sericitization. The chemical composition of the pyroxene is En51.95Fs44.53Wo3.52, biotite has Fe/(Fe+Mg):0.42, Mg/(Fe+Mg):0.59, and plagioclase is Ab63.5An34.55Or1.95. Whole rock chemistry shows a chemical composition; SiO2: 45.15 %, Al2O3: 14.04 %, Fe2O3: 16.01 %, MgO: 5.65 %, CaO: 7.58 % and TiO2: 3.59 %. There is an enrichment of LREE and a depletion of HREE. Based on the minerals, mineral chemistry and the geochemistry of the studied rock, the rock is mafic and hydrous minerals formed by hydration recrystallization of pyroxene. The rock has extensively retrogressed but has not been affected by any form of deformation.
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Haglund, David G. „La nouvelle géopolitique des minéraux : Une étude sur l’évolution de l’impact international des minéraux stratégiques“. Études internationales 13, Nr. 3 (12.04.2005): 445–71. http://dx.doi.org/10.7202/701383ar.
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This article explores changes in the international political significance of "strategic minerals" over the past half-century. The method of analysis is comparative historical, or "diachronic", and the major issues examined are: 1) minerals as a cause of international conflict; 2) minerals as a factor contributing to the military potential of states; and 3) the question of mineral scarcity. In addition to the above issues, the author analyzes two central concepts, "geopolitics" and "strategic minerals" . He concludes that while it does make sense to speak of a "new geopolitics of Minerals" in the post-1973 era, there are nevertheless important ways in which recent strategic-minerals issues resemble those of the earlier period under examination, the interwar years (and, in particular, the 1930s). What does not seem to have changed in respect of strategic minerals since the 1930 s is that access to them continues ultimately to be a function of political processes, and therefore the access question remains what it was, a matter of geopolitical concern. Where there have been differences in the relevance of strategic minerals, these have mainly consisted in: 1) the declining importance of minerals as a major contributory factor in the breakdown of world order; 2) the lessening of what had formerly been a deterministic equation between mineral possession and military potential; and 3) the increased salience in the post-1973 era of the perception that access will be affected by the growing scarcity of minerals, whether due to the actual depletion of reserves or politically induced supply disruptions.
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Elsayed, Omnia, Nahla Abd El Ghaffar, Abdel Moneim Mahmoud und Ismail Ismail. „Significant Enrichment of Rare Earth Element Concentrations in Stream Sediments of Sharm El-Sheikh Area, Southern Sinai-Egypt: Geochemical Prospecting and Heavy Mineral Survey“. Iraqi Geological Journal 56, Nr. 1B (28.02.2023): 1–15. http://dx.doi.org/10.46717/igj.56.1b.1ms-2023-2-9.
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Economic rare earth element bearing-heavy mineral accommodation in alluvial deposits (stream sediments) is a well-known process caused by varying rates of weathering and transportation of heavy minerals and sediments, which is significant in geochemical exploration. In the present work, stream sediment samples from Wadi Lethi, Sharm El-Sheikh, were systematically collected. The collected stream sediments were investigated mineralogically and geochemically using collaborative techniques. The separated heavy fractions have been analyzed for trace elements and Rare Earth Element. Important heavy minerals identified are monazite, sphene, apatite, garnet, xenotime, magnetite, ilmenite, and hematite, with subordinate riebeckite, epidote, and chlorite. Geochemical analyses of the separated heavy minerals revealed an abnormal concentration of total Rare Earth Element that was more than eleven times higher than in the studied area's granitic rocks. The Rare Earth Elements trends of these minerals depict the enrichment of light rare earth elements and the depletion of heavy rare earth elements, as well as the typical negative Eu anomaly found in granitic magma.
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Mitra, Sam. „Depletion, technology, and productivity growth in the metallic minerals industry“. Mineral Economics 32, Nr. 1 (12.11.2018): 19–37. http://dx.doi.org/10.1007/s13563-018-0165-8.
Der volle Inhalt der QuelleDissertationen zum Thema "Minerals Depletion"
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Mitra, Sam. „Depletion, technology and productivity growth in metallic minerals industry“. Thesis, University of Dundee, 2016. https://discovery.dundee.ac.uk/en/studentTheses/9cec3601-f1de-414c-8d45-860f61451567.
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Owing to the diverse geological processes of genesis, metals occur in earth’s crust in a variety of minerals that form ore deposits across the globe. These deposits significantly differ in terms of their physical and chemical characteristics, and conditions of hosting. Productivity growth in any given metal industry is therefore governed by not only the advancements in technology, but also this unique variation in its natural input in course of cumulative extraction and depletion. Detailed analysis of the changes in process input intensities and sector productivity corresponding to a representative spectrum of geological transitions in copper ores reveals that the continuous and incremental technological developments had successfully offset the detrimental effects of depletion on sector productivity, often aided by the geological characteristics that changed to the miners’ advantage. However, the transition of ores below a threshold level of purity and then into the next prevalent chemical composition, was found to cause a steep rise in input intensities that would lead to a fall in productivity despite the introduction of a widely acclaimed innovative process of copper extraction. The study shows that the impacts of depletion are neither linear, nor uniform, and not always detrimental to productivity. It shows the usefulness of productivity studies in estimating the impacts depletion that may not proceed in strictly sequential manner in the short and medium term, as well as evaluating the benefits of technological change. Though the study is primarily based on copper industry, the findings hold relevance for other metal industries too.
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Vikström, Hanna. „Rare Metals: Energy Security and Supply“. Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-168130.
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Lithium and neodymium are two critical materials in our modern society, many technological solutions depend on them. Lithium is used in batteries, which are used in cars and portable electronics. Neodymium, which is a rare earth element, is mainly used in permanent magnets which are used in smartphones, hard disc drives and turbines. There are many reports regarding the availability of the metals, with different results. The available data on the reserves varies considerably, from the few sources there are. In this report, based on geological availability, forecasts are done to investigate how much the production can increase and when it will peak. The prognoses are based on historic production to which different functions, the logistic, gompertz and richards, are fitted with the least square method. The production will peak in the end of this century and in the beginning of the next century for both metals. The production of lithium does not seem to be sufficient for both producing electric and hybrid cars with only li-ion batteries along with fusion. The neodymium production will be sufficient for producing a lower percentage of direct driven wind turbines and electric cars with NiMH batteries. Lithium in seawater is sometimes considered a future source. Since the lithium concentration is low, large volumes have to be processed in order to extract a reasonable amount of lithium. Currently it is not economic to extract lithium from seawater.
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Rubasinghege, Gayan Randika S. „Chemical and photochemical reactions on mineral oxide surfaces in gaseous and liquid phases: environmental implications of fate, transport and climatic impacts of mineral dust aerosol“. Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1173.
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Mineral dust aerosols emitted from the Earth crust during various natural and anthropogenic processes continuously alter the chemical balance of the atmosphere via heterogeneous processes and thus, impact on the global climate. Understanding of heterogeneous chemistry and photochemistry on mineral dust has become vital to accurately predict the effect of mineral dust loading on the Earth's atmosphere. Here, laboratory measurements are coupled with model studies to understand heterogeneous chemistry and photochemistry in the atmosphere with the specific focus on reactions on mineral oxide surfaces.
Heterogeneous uptake of gas phase HNO3 on well characterized metal oxides, oxyhydroxides and carbonates emphasized binding of nitric acid to these surfaces in different modes including monodentate, bidentate and bridging under dry conditions. It is becoming increasingly clear that the heterogeneous chemistry, including uptake of HNO3, is a function of relative humidity (RH) as water on the surface of these particles can enhance or inhibit its reactivity depending on the reaction. All the studied model systems showed a significant uptake of water with the highest uptake by CaCO3. Quantitative analysis of water uptake indicated formation of multilayers of water over these reactive surfaces. Under humid conditions, two water solvated nitrate coordination modes were observed that is inner-sphere and outer-sphere, which differ by nitrate proximity to the surface.
Photochemical conversion of nitric acid to gas phase nitrous oxide, nitric oxide and nitrogen dioxide through an adsorbed nitrate intermediate under different atmospherically relevant conditions is shown using transmittance FTIR and XPS analysis. The relative ratio and product yields of these gas phase products change with relative humidity. Photochemistry of adsorbed nitrate on mineral aerosol dust may be influenced by the presence of other distinct gases in the atmosphere making it complicated to understand. This thesis converses formation of active nitrogen, NOx and N2O, and chlorine, ClOx, species in the presence of co-adsorbed trace gases, that could potentially regulate the peak concentration and geographical distribution of atmospheric ozone. Here we report formation of atmospheric N2O, from the photodecomposition of adsorbed nitrate in the presence of co-adsorbed NH3 via an abiotic mechanism that is favorable in the presence of light, relative humidity and a surface. Estimated annual production of N2O over the continental United States is 9.3+0.7/-5.3 Gg N2O, ~5% of total U.S. anthropogenic N2O emissions. Not only NH2 but also gaseous HCl react with adsorbed nitrate to activate "inert" N and Cl reservoir species, yielding NOCl, NOx, Cl and Cl2, through adsorbed nitrate under different atmospherically relevant conditions.
Mineral dust aerosol is a major source of bioavailable iron to the ocean with an annual deposition of ~ 450 Tg of dust into the open ocean waters. In this study, we report enhanced Fe dissolution from nano scale Fe-containing minerals, i.e.alpha-FeOOH, beyond the surface area effects that can be attributed to the presence of more reactive sites on specific crystal planes exposed. We further report with clear evidence that aggregation impacts on dissolution. Proton-promoted dissolution of nanorods is nearly or completely quenched in the aggregated state. Acid type, presence of oxyanions and light are several other key factors responsible for regulating for iron dissolution. The work reported in this thesis provides insight into the heterogeneous chemistry and photochemistry of mineral dust aerosol under different atmospherically relevant conditions.
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Lodi, Karina Bortolin [UNESP]. „Repercussões minerais ósseas no alcoolismo crônico associado à deficiência hormonal em ratos“. Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/100690.
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lodi_kb_dr_sjc.pdf: 1562436 bytes, checksum: 246eb585fc5a0a4430283de97ba05ad6 (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O alcoolismo se relaciona com a redução da massa óssea, aumenta o risco de fraturas e, ocorrendo a fratura, pode piorar o reparo ósseo. Acima de tudo, fraturas e alcoolismo são associados a longos períodos de hospitalização e alta mortalidade. Mais de 50% dos atendimentos ambulatoriais de alcoólicos mostram evidencias de perda óssea. Além disso, já foi evidenciada em humanos e animais uma relação negativa entre consumo de etanol e densidade mineral óssea. A origem desses efeitos deletérios pode ocorrer além da ação direta no osso, sendo através dos distúrbios hormonais e deficiências nutricionais que acompanham os casos de consumo excessivo de etanol. O objetivo deste estudo foi investigar a resposta biomecânica sobre o fêmur de ratos, bem como os parâmetros bioquímicos e de composição mineral óssea decorrente da deficiência hormonal e consumo crônico de etanol. Ratos Wistar machos e fêmeas (n=108) foram divididos em machos orquiectomizados (ORQ), fêmeas ovariectomizadas (OVX) ou Sham-operados, e subdivididos de acordo com a dieta (grupos ad libitum, isocalórico e etanol 20%). Após um mês da cirurgia, os animais foram alimentados diariamente com a dieta controlada por 8 semanas. Foram avaliadas as condições nutricionais. Ca e P foram analisados por teste bioquímico no sangue e por espectrometria de fluorescência de raios-x no fêmur. As propriedades biomecânicas também foram analisadas pelo teste de flexão em 3 pontos. Os dados revelam que a deficiência hormonal promove ganho de massa corporal nas fêmeas e perda nos machos. Os resultados também revelam hiperfosfatemia plasmática nos grupos etanol-ORQ e etanol-OVX. Redução da proporção molar de Ca/P e de Ca ósseo em todos os grupos de dieta alcoólica. Do mesmo modo, a espectrometria revelou perda de P ósseo nos grupos Sham-ad libitum. As propriedades biomecânicas...
Ethanol abuse is correlated with decreased bone mass, increase of fracture risks and, should a fracture occur, may impair bone healing. Overall, fractures in alcoholics are associated with longer hospitalization and increased mortality. Up to 50% of ambulatory chronic alcoholics demonstrate evidence of bone loss. Additionally, a negative correlation between ethanol intake and bone mineral density in humans and animal models has been demonstrated. The basis for these consequent deleterious effects may occur beyond the direct actions on bone, due to hormonal disturbance and nutritional deficiencies that follow excessive ethanol intake. The aim of this study was to investigate the biomechanical effect on rat femur as well the biochemical parameters and bone mineral contents caused by hormonal deficiency and ethanol abuse. Male and female Wistar rats (n=108) were divided in male orchiectomy (ORQ), female ovariectomy (OVX) or Sham-operated and subdivided by diet (ad libitum, pair-fed, ethanol 20% groups). After 1 month from surgery, they were daily fed with controlled diet for 8 weeks. Ca and P were analyzed by biochemical test in the blood and by X-ray fluorescence spectrometry of femur area. Biomechanical properties were also analyzed b3y 3-point bending test. These findings demonstrate that hormonal depletion promoted an increase in female body weight and loss on male. The data also revealed serum hyperphosphataemia in ethanol-ORQ and ethanol-OVX groups. Reduce on bone Ca/P molar ratio and bone Ca content in all ethanol groups. In similarity, spectrometry indicated decreased in bone P content in Sham-ad libitum groups. Biomechanical properties were affected by hormonal depletion only in male. The relationships among ethanol consume and hormonal deficit support the hypothesis that they affects sinergically the body nutrition, disturb Ca and P homeostasis and may mediate... (Complete abstract click electronic access below)
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Lodi, Karina Bortolin. „Repercussões minerais ósseas no alcoolismo crônico associado à deficiência hormonal em ratos /“. São José dos Campos : [s.n.], 2010. http://hdl.handle.net/11449/100690.
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Resumo: O alcoolismo se relaciona com a redução da massa óssea, aumenta o risco de fraturas e, ocorrendo a fratura, pode piorar o reparo ósseo. Acima de tudo, fraturas e alcoolismo são associados a longos períodos de hospitalização e alta mortalidade. Mais de 50% dos atendimentos ambulatoriais de alcoólicos mostram evidencias de perda óssea. Além disso, já foi evidenciada em humanos e animais uma relação negativa entre consumo de etanol e densidade mineral óssea. A origem desses efeitos deletérios pode ocorrer além da ação direta no osso, sendo através dos distúrbios hormonais e deficiências nutricionais que acompanham os casos de consumo excessivo de etanol. O objetivo deste estudo foi investigar a resposta biomecânica sobre o fêmur de ratos, bem como os parâmetros bioquímicos e de composição mineral óssea decorrente da deficiência hormonal e consumo crônico de etanol. Ratos Wistar machos e fêmeas (n=108) foram divididos em machos orquiectomizados (ORQ), fêmeas ovariectomizadas (OVX) ou Sham-operados, e subdivididos de acordo com a dieta (grupos ad libitum, isocalórico e etanol 20%). Após um mês da cirurgia, os animais foram alimentados diariamente com a dieta controlada por 8 semanas. Foram avaliadas as condições nutricionais. Ca e P foram analisados por teste bioquímico no sangue e por espectrometria de fluorescência de raios-x no fêmur. As propriedades biomecânicas também foram analisadas pelo teste de flexão em 3 pontos. Os dados revelam que a deficiência hormonal promove ganho de massa corporal nas fêmeas e perda nos machos. Os resultados também revelam hiperfosfatemia plasmática nos grupos etanol-ORQ e etanol-OVX. Redução da proporção molar de Ca/P e de Ca ósseo em todos os grupos de dieta alcoólica. Do mesmo modo, a espectrometria revelou perda de P ósseo nos grupos Sham-ad libitum. As propriedades biomecânicas... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: Ethanol abuse is correlated with decreased bone mass, increase of fracture risks and, should a fracture occur, may impair bone healing. Overall, fractures in alcoholics are associated with longer hospitalization and increased mortality. Up to 50% of ambulatory chronic alcoholics demonstrate evidence of bone loss. Additionally, a negative correlation between ethanol intake and bone mineral density in humans and animal models has been demonstrated. The basis for these consequent deleterious effects may occur beyond the direct actions on bone, due to hormonal disturbance and nutritional deficiencies that follow excessive ethanol intake. The aim of this study was to investigate the biomechanical effect on rat femur as well the biochemical parameters and bone mineral contents caused by hormonal deficiency and ethanol abuse. Male and female Wistar rats (n=108) were divided in male orchiectomy (ORQ), female ovariectomy (OVX) or Sham-operated and subdivided by diet (ad libitum, pair-fed, ethanol 20% groups). After 1 month from surgery, they were daily fed with controlled diet for 8 weeks. Ca and P were analyzed by biochemical test in the blood and by X-ray fluorescence spectrometry of femur area. Biomechanical properties were also analyzed b3y 3-point bending test. These findings demonstrate that hormonal depletion promoted an increase in female body weight and loss on male. The data also revealed serum hyperphosphataemia in ethanol-ORQ and ethanol-OVX groups. Reduce on bone Ca/P molar ratio and bone Ca content in all ethanol groups. In similarity, spectrometry indicated decreased in bone P content in Sham-ad libitum groups. Biomechanical properties were affected by hormonal depletion only in male. The relationships among ethanol consume and hormonal deficit support the hypothesis that they affects sinergically the body nutrition, disturb Ca and P homeostasis and may mediate... (Complete abstract click electronic access below)
Orientador: Rosilene Fernandes da Rocha
Coorientador: Ana Maria do Espírito Santo
Banca: Lafayette Nogueira Junior
Banca: Renata Andrade Bitar
Banca: Yasmin Rodarte Carvalho
Banca: Vilma Leyton
Doutor
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Gustafsson, Isabel, und Agnes Rönnblom. „Life Cycle Assessment of a surface radar system : A case study at Saab Electronic Defence Systems“. Thesis, Linköpings universitet, Industriell miljöteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122720.
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This master thesis was performed with the main purpose of evaluating the environmental performance of a surface radar system with the means of a life cycle assessment, LCA. Saab Electronic Defence Systems, EDS, was the initiator and driver of the project, and is also owner of the radar system evaluated. Apart from the environmental performance the project was carried out with the intention of EDS wanting to gain knowledge about working with LCA, both in terms of methodology and to get an insight into whether and how well they can work with the tool in their current situation. In order to assess the radar systems environmental impact through its entire life cycle there was emphasis on the use phase since the object can be used in several different ways under various circumstances. Eight different operational profiles were thus addressed in order to compare these variations in use scenarios. In addition, studies were performed on whether there exist any guidelines on how use phase scenarios can or should be defined when conducting an LCA. The LCA was performed in accordance with the ISO 14040 family and the database Ecoinvent has been used for mapping the in- and outflows. To calculate the potential environmental impacts ReCiPé was used, where three out of 18 impact categories were chosen to focus upon in agreement with EDS, namely climate change, fossil depletion and mineral resource depletion. Apart from within some business areas, conclusion could be drawn that no general guidelines exist for the definition of the use phase in an LCA. Besides being described in order to increase transparency in the assessment, no further requirements are set by ISO. Found through the assessment is that the use phase shows a major contribution to the overall environmental impacts from the entire life cycle, by being accountable for roughly 85 %. Depending on impact category, the cause lies with either the radar operation due to its large amount of diesel consumption or with the extraction of materials needed to provide for the replacement of faulty components during maintenance. In accordance with their share of the object’s weight, aluminium, copper and iron stand for about 77 % of the materials environmental impact. Noticeable is though that gold takes place on the top ten list of contributing materials with its 0.0001 % of the total weight, meaning that not only do the large amounts of a material matter, more important is the relation between weight and environmental impact. Regarding the eight operational profiles, out of the two parameters compared the radar operation proved to have significantly larger impacts in all three impact categories than the vehicle operation. Interestingly enough, it was found that if the radar and vehicle would have the same amount of operating hours, the vehicle would have larger impacts than the radar. In conclusion, from an environmental perspective it is more important to keep the vehicle operating hours low. However, since the radar operating hours are high at this point it would make a significant difference in reducing the radar fuel consumption. Lastly, for EDS to be able to continue in working with LCA, conclusions are drawn that a more qualified information base needs to be built up within the organization to avoid as much assumptions as possible, this in order to achieve more reliable results.Detta examensarbete utfördes med det huvudsakliga syftet att utvärdera miljöprestandan av ett markradarsystem med hjälp av en livscykelanalys, LCA. Saab Electronic Defence Systems, EDS, både tog initiativ till och drev projektet. De är även ägare av det utvärderade markradar-systemet. Utöver miljöprestandan utfördes examensarbetet även med avsikt att bistå EDS med kunskap om att arbeta med LCA, både vad gäller metodiken och för att ge en inblick i om och hur väl de kan arbeta med verktyget under nuvarande förhållanden. För att kunna bedöma radarsystemets miljöpåverkan genom hela dess livscykel lades betoning på användningsfasen då objektet kan användas på ett flertal sätt under olika omständigheter. Åtta olika driftsprofiler sattes därmed upp för att jämföra dessa varierande användnings-scenarier. Dessutom studerades om det idag finns några riktlinjer för hur användningsfasen kan eller bör definieras vid utförandet av en LCA. Analysen utfördes i enlighet med ISO 14040-familjen och databasen Ecoinvent har använts för kartläggning av in- och utflöden. För att beräkna den potentiella miljöpåverkan som uppstår användes ReCiPé, där tre utav 18 miljö-påverkanskategorier valdes att fokusera på, nämligen klimatförändring, fossil utarmning och utarmning av mineraler. Bortsett från några branscher kunde slutsatsen dras att inga generella riktlinjer finns för definitionen av användningsfasen i en LCA. Utöver att beskriva sina val i syfte att öka transparensen i analysen ställs inga ytterligare krav av ISO. Genom att bidra till omkring 85 % av den totala miljöpåverkan visade sig användningsfasen vara överlägsen i förhållande till övriga faser i livscykeln. Beroende på påverkanskategori är den bakomliggande orsaken antingen radardriften, på grund av sin stora mängd dieselförbrukning, eller utvinningen av de ämnen som behövs för utbytet av felaktiga komponenter vid underhåll. I enlighet med deras andel av hela den funktionella enhetens vikt står aluminium, koppar och järn för ungefär 77 % av de utvunna ämnenas miljöpåverkan. Noterbart är dock att guld placerar sig på topp tio-listan över bidragande ämnen med sin andel på 0.0001 % av den totala vikten, vilket innebär att det inte bara är stora mängder av ämnen som spelar roll utan också förhållandet mellan vikt och miljöpåverkan. Vad gäller de åtta driftsprofilerna och dess två ingående parametrar visade sig radardrift ha betydligt större påverkan inom alla tre miljö-påverkanskategorier än fordonsdrift. Anmärkningsvärt nog visade det sig att om radar och fordon skulle ha samma driftstider skulle fordonsdrift bidra med den större miljöpåverkan av de två. Ur miljösynpunkt skulle det därför vara viktigare att hålla fordonets driftstid nere, men eftersom driftstiden för radar i dagsläget är avsevärt högre skulle det göra större skillnad att reducera radarns dieselförbrukning. Slutligen, för att EDS ska kunna fortskrida sitt arbete med LCA, dras slutsatsen att en mer kvalificerad informationsbas måste byggas upp inom organisationen. Detta för att i så hög grad som möjligt kunna undvika antaganden, i syfte att uppnå mer tillförlitliga resultat.
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David, Richard Boarato. „Especificidade do apetite ao sódio: uma possível contribuição hormonal“. Universidade Federal de São Carlos, 2006. https://repositorio.ufscar.br/handle/ufscar/1282.
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Previous issue date: 2006-08-24The hypothesis of a synergy between two hormones responsible for sodium conservation, aldosterone and angiotensin II (ANG II), explains the expression of a characteristic of sodium appetite, hypertonic NaCl intake, in a hypovolemic animal. Hypertonic NaCl intake can be induced in normovolemic rats that received a combined treatment of mineralocorticoid and ANG II at individual doses not sufficient to induce sodium intake (paradigmatic synergy test). Considering the motivation to specific sodium intake another characteristic of sodium appetite, the objective of the present dissertation was to find out a role for the interaction between mineralocorticoid and ANG II on the specificity of sodium appetite. Sprague-Dawley Holtzman rats (≅ 300 g b.w.) were housed with access to water and one or more palatable (0.01 M KCl, 0.05 mM CaCl2, 0.15 M NaHCO3, 0.15 M NaCl) or hypertonic (0.50 M NaCl) mineral solutions for ingestion. In two-bottle tests, a bottle contained water and another bottle contained either 0.01 M KCl, 0.15 M NaHCO3, 0.15 M NaCl or 0.50 M NaCl. In five-bottle tests, a bottle contained water and each one of the remaining four bottles contained either 0.01 M KCl, 0.05 mM CaCl2, 0.15 M NaHCO3 or 0.15 M NaCl, respectively. In sodium depletion tests, intact rats received each a 10 mg sc. injection of furosemide or vehicle followed by 24 h access to sodium deficient food and water. Then, food was removed and mineral solutions and water were offered for recording their intake (sodium appetite test). In the paradigmatic synergy test, the animals received daily single sc injection of 2.5 mg of deoxycorticosterone acetate (DOCA) or sunflower oil (vehicle) for three days and a left lateral cerebroventricular injection of 50 ng of ANG II four hours after the last DOCA or oil injection. Fluid intake record began immediately after ANG II injection and food removal. The daily intake record showed no preference for any solution or water when animals had access to five bottles. Sodium depletion induced a preferential sodium intake, with higher NaCl than NaHCO3 intake, in either two- or five-bottle sodium appetite tests. DOCA alone enhanced the daily 0.15 M NaCl and NaHCO3 intake, but did not alter KCl or 0.50 M NaCl intake in two-bottle tests. In the paradigmatic tests with normovolemic animals, ANG II combined to oil induced the ingestion of all three palatable mineral solutions (KCl, NaHCO3, NaCl) and water, in two-bottle tests, and preference for NaHCO3 in five-bottle tests. DOCA pretreatment enhanced only sodium solution intake, particularly NaCl intake, induced by ANG II in two-bottle tests (0.15 M NaCl: DOCA/ANG II = 24.5 ± 6.7 ml/120 min. vs. OIL/ANG II = 9.2 ± 1.8 ml/120 min.; 0.15 M NaHCO3: DOCA/ANG II = 17.0 ± 1.8 ml/120 min. vs. OIL/ANG II = 14.6 ± 2.1 ml/120 min.; 0.01 M KCl: DOCA/ANG II = 9.8 ± 1.9 ml/120 min. vs. 11.9 ± 1.2 ml/120 min.), and enhanced by 80 % the total sodium solution intake in the beginning of the five-bottle test. The combined effect of DOCA with ANG II on the induction of 0.50 M NaCl intake in a two-bottle test was replicated in our animals. The results from the paradigmatic synergy test are coherent with results from sodium appetite tests, suggesting that the mineralocorticoid may turn the effect of ANG II on mineral intake more selective to sodium intake. Thus, the combined ANG II and mineralocorticoid action could contribute to the expression of two characteristics of sodium appetite, not only the acceptance of hypertonic sodium solutions, but also the selective sodium intake.
A hipótese do sinergismo entre dois hormônios responsáveis pela conservação de sódio, a aldosterona e a ANG II, explica uma característica do apetite ao sódio, a ingestão de NaCl hipertônico em um animal hipovolêmico. Ingestão de NaCl hipertônico pode ser induzida em ratos normovolêmicos que receberam um tratamento combinado de mineralocorticóide e ANG II, em doses individuais insuficientes para induzir a ingestão de sódio (teste paradigmático do sinergismo). Sendo a motivação para uma ingestão específica de sódio uma outra característica do apetite ao sódio, o objetivo desta dissertação foi o de procurar um papel para a interação entre mineralocorticóide e ANG II na especificidade do apetite ao sódio. Foram utilizados ratos Sprague-Dawley Holtzman (≅ 300 g p.c.) ambientados com livre acesso a bebedouros com água e uma ou mais soluções minerais palatáveis (KCl 0,01 M, CaCl2 0,05 mM, NaHCO3 0,15 M, NaCl 0,15 M) ou hipertônica (NaCl 0,50 M). Em testes de dois bebedouros, um dos bebedouros continha água e o outro, solução de KCl 0,01 M, NaHCO3 0,15 M, NaCl 0,15 M ou NaCl 0,50 M. Em testes de cinco bebedouros, um dos bebedouros continha água e cada um dos demais uma solução de KCl 0,01 M, CaCl2 0,05 mM, NaHCO3 0,15 M ou NaCl 0,15 M. Testes com dois ou cinco bebedouros foram empregados em animais depletados de sódio e no teste paradigmático do sinergismo. Nos testes de depleção de sódio, os animais receberam injeção sc de 10 mg de furosemida ou veículo, seguida de acesso a uma dieta hipossódica e água por vinte e quatro horas. Em seguida, o alimento foi removido e foram oferecidas soluções minerais para registro da ingestão das mesmas e de água (teste do apetite ao sódio). No teste paradigmático do sinergismo, os animais receberam injeção sc de 2,5 mg de acetato de desoxicorticosterona (DOCA) ou óleo de girassol (veículo) uma vez ao dia, durante três dias, e uma injeção de 50 ng de ANG II (ou salina) no ventrículo lateral esquerdo, quatro horas após a última injeção de DOCA ou óleo. Passou-se a registrar a ingestão de líquidos imediatamente após a injeção de ANG II e remoção da ração. O registro da ingestão diária mostrou que não houve preferência por nenhuma solução ou água durante o período de ambientação com cinco bebedouros. A depleção de sódio induziu ingestão preferencial de sódio no teste do apetite ao sódio, sendo a ingestão de NaCl 0,15 M maior do que a de NaHCO3 tanto nos testes de dois como de cinco bebedouros. O tratamento com apenas DOCA aumentou a ingestão diária de NaCl 0,15 M e de NaHCO3 sem alterar a ingestão diária de KCl e de NaCl 0,50 M, em testes de dois bebedouros. No teste paradigmático com ratos normovolêmicos, a ANG II combinada ao óleo promoveu ingestão das três soluções minerais palatáveis (KCl, NaHCO3, NaCl) e de água em testes de dupla escolha, e preferência ao NaHCO3 no teste com cinco bebedouros. O pré-tratamento com DOCA potenciou o efeito da ANG II apenas sobre a ingestão das soluções sódicas, mais evidente para NaCl, no teste com dois bebedouros (NaCl 0,15 M: DOCA/ANG II = 24,5 ± 6,7 ml/120 min. vs. ÓLEO/ANG II = 9,2 ± 1,8 ml/120 min.; NaHCO3 0,15 M: DOCA/ANG II = 17,0 ± 1,8 ml/120 min. vs. ÓLEO/ANG II = 14,6 ± 2,1 ml/120 min.; KCl 0,01 M: DOCA/ANG II = 9,8 ± 1,9 ml/120 min. vs. 11,9 ± 1,2 ml/120 min.), além de aumentar em 80 % a ingestão total de soluções sódicas no início do teste com cinco bebedouros. O efeito da indução de ingestão de NaCl 0,50 M pela combinação de DOCA com ANG II em testes de dois bebedouros foi replicado nos nossos animais. Os resultados do teste paradigmático do sinergismo são coerentes com os testes do apetite ao sódio, sugerindo que o mineralocorticóide possa tornar mais seletivo o efeito da ANG II sobre a ingestão mineral. Assim, uma interação entre ANG II e mineralocorticóide poderia contribuir para a expressão de duas características do apetite ao sódio, não apenas a aceitação de soluções hipertônicas de NaCl, mas também a ingestão seletiva de sódio.
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Cantuarias-Villessuzanne, Carmen Amalia. „La mesure économique de la dépréciation du capital minier au Pérou“. Thesis, Bordeaux 4, 2012. http://www.theses.fr/2012BOR40009/document.
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Le Pérou, extrêmement riche en minerais, connaît depuis les années 2000 une forte croissance économique. Àla question de savoir si sa richesse minérale condamne le Pérou à la malédiction des ressources naturelles, nousrépondons que ce n’est pas le cas à l’heure actuelle, mais nous mettons en évidence une forte dépendance vis-à-visde l’activité minière. La question centrale est celle du développement durable de l’activité minière. La mesure dela dépréciation du capital minier (dcm) est l’indicateur fondamental pour évaluer la situation. Diverses méthodesd’estimation existent, mais notre analyse microéconomique basée sur la règle de Hotelling fournit une valeurd’environ 7 % du pib sur la période 2000–2008, soit le double de l’approximation donnée par la Banque Mondiale.Nous proposons d’intégrer la dcm aux indicateurs macroéconomiques traditionnels, ce qui permet de mettreen évidence la surestimation de la croissance économique. Conformément à la règle de Hartwick, il apparaîtclairement que le développement péruvien n’est pas durable ; les revenus miniers ne compensent pas la dcmet ne sont pas réinvestis en faveur du développement du pays. Il faudrait donc taxer les entreprises minières àhauteur de la dcm, et créer un fonds de ressources naturelles. Nos résultats montrent qu’épargner seulement 8 %de la dcm permettrait d’atteindre un revenu durable pour les générations futures. La création d’un tel fonds deressources naturelles aurait également pour avantage de réduire l’instabilité macroéconomique et de promouvoirune meilleure gouvernabilitéSince the 2000s, Peru, a country extremely rich in minerals has experienced strong economic growth. WouldPeru be condemned to the resource curse because of its mineral wealth? For now this is not the case; howeverwe point up a strong dependence upon the mining sector. The main question relates to the sustainability of themining industry. The mineral depletion rate is a fundamental indicator to assess the situation. To calculate this,there are many forecasting methods available ; our microeconomic analysis based on the Hotelling rule providesa value of around 7 % of gdp for the period between 2000 and 2008, which represents double the estimation ofthe World Bank.We recommend the mineral depletion be taken into account when calculating traditional macroeconomic indicators;it would highlight the overestimation of economic growth. According to the Hartwick rule, it is clearthat Peruvian development is not sustainable; mining revenues do not offset the mineral depletion and are notreinvested in the development of the country. Therefore, the solution should be to tax mining companies at alevel equivalent to that of depletion and, with the new income, to create a natural resource fund. Saving only8 % of the mineral depletion would suffice to generate sustainable rent for futures generations. In addition, thecreation of a natural resource fund would reduce macroeconomic instability and enforce better governance
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Eshun, Samuel Yawson. „The optimal depletion of mineral deposit“. Thesis, 1992. http://hdl.handle.net/10539/22780.
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A project report submitted to the faculty of Engineering, University of the Witwatersrand, in partial fulfilment of requirement of Master of Science in Engineering
Johannesburg, 1992The optimal depletion of a mineral deposit involves the optimisation of all the proccesses involved in the mining operation. [Abbreviated Abstract. Open document to view full version]
MT2017
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„Mineral depletion, with special reference to petroleum“. Massachusetts Institute of Technology, Center for Energy Policy Research, 1988. http://hdl.handle.net/1721.1/29488.
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by M.A. Adelman."Revised May 1988."--T.p.
Includes bibliographical references.
Research supported by the National Science Foundation. SES-8412971 Research supported by the Center for Energy Policy Research of the M.I.T. Energy Laboratory.
Bücher zum Thema "Minerals Depletion"
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Campbell, Colin J. Campbell's Atlas of Oil and Gas Depletion. 2. Aufl. New York, NY: Springer New York, 2013.
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Bartlik, Barbara, Janet Mindes und Sheila Sperber Haas. Sexual Dysfunction Secondary to Micronutrient Deficiency (DRAFT). Herausgegeben von Madeleine M. Castellanos. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190225889.003.0008.
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Diverse micronutrient deficiencies can impair sexual function. The many recognized factors that can result in depleted vitamins and minerals include suboptimal diet, aging, toxins, malabsorption, and depleted soil. This chapter focuses on the generally unrecognized depleting effects due to a large and diverse variety of common pharmaceutical medications. Nearly half of all Americans take prescription drugs, frequently more than one, and many of them fall within this category and are discussed here. This chapter provides a detailed summary of clinical experience and research evidence for the depletion of those micronutrients with the greatest negative impact on healthy sexual functioning, and for the drugs involved, and includes guidance on identifying and then resolving each of these deficiencies. The standard of care for patients with sexual dysfunction is psychotherapy or medication, both of which are often only minimally or partially effective. Yet identifying and correcting drug-induced micronutrient depletion often resolves sexual dysfunction.
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Bartlik, Barbara, Amandeep Kaur, Chelsea Schoen und Julie Kolzet. Birth Control Pills and Hormonal Contraception (DRAFT). Herausgegeben von Madeleine M. Castellanos. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190225889.003.0009.
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This chapter reviews the existing literature on the use of hormonal contraception (HC) and sexual functioning. In the cases where HC has been shown to lead to a decrease in sexual functioning, the chapter presents several hypotheses for the mechanisms that could be responsible for those changes, such as micronutrient depletion and elevations in sex hormone binding globulin with consequent reductions in free testosterone. Throughout this chapter, the authors make a case for clinicians to take care to inform patients of the potential sexual side effects of hormonal contraceptives, bearing in mind that it may be advisable for women who use them to supplement with certain vitamins and minerals. This may be an especially important consideration for women with genetic polymorphisms in methylation. The chapter concludes with a clinical case study.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
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On Borrowed Time?: Assessing the Threat of Mineral Depletion. RFF Press, 2002.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
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Tilton, John E. On Borrowed Time: Assessing the Threat of Mineral Depletion. Taylor & Francis Group, 2010.
Den vollen Inhalt der Quelle findenBuchteile zum Thema "Minerals Depletion"
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Nguejio, Josiane, Jérôme Crépin, Cécilie Duhamel, Fabrice Gaslain, Catherine Guerre, François Jomard und Marc Maisonneuve. „Diffusion Processes as Possible Mechanisms for Cr Depletion at SCC Crack Tip“. In The Minerals, Metals & Materials Series, 337–57. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-67244-1_22.
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Nguejio, Josiane, Jérôme Crépin, Cécilie Duhamel, Fabrice Gaslain, Catherine Guerre, François Jomard und Marc Maisonneuve. „Diffusion Processes as Possible Mechanisms for Cr Depletion at SCC Crack Tip“. In The Minerals, Metals & Materials Series, 337–57. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-030-04639-2_22.
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Hinsinger, Philippe, Michael J. Bell, John L. Kovar und Philip J. White. „Rhizosphere Processes and Root Traits Determining the Acquisition of Soil Potassium“. In Improving Potassium Recommendations for Agricultural Crops, 99–117. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_4.
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AbstractPlants acquire K+ ions from the soil solution, and this small and dynamic pool needs to be quickly replenished via desorption of surface-adsorbed K from clay minerals and organic matter, by release of interlayer K from micaceous clay minerals and micas, or structural K from feldspars. Because of these chemical interactions with soil solid phases, solution K+ concentration is kept low and its mobility is restricted. In response, plants have evolved efficient strategies of root foraging. Root traits related to root system architecture (root angle and branching), root length and growth, together with root hairs and mycorrhiza-related traits help to determine the capacity of plants to cope with the poor mobility of soil K. Rooting depth is also important, given the potentially significant contribution of subsoil K in many soils. Root-induced depletion of K+ shifts the exchange equilibria, enhancing desorption of K, as well as the release of nonexchangeable, interlayer K from minerals in the rhizosphere. Both these pools can be bioavailable if plant roots can take up significant amounts of K at low concentrations in the soil solution (in the micromolar range). In addition, roots can significantly acidify their environment or release large amounts of organic compounds (exudates). These two processes ultimately promote the dissolution of micas and feldspars in the rhizosphere, contributing to the mining strategy evolved by plants. There are thus several root or rhizosphere-related traits (morphological, physiological, or biochemical) that determine the acquisition of K by crop species and genotypes.
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Lange, Glenn-Marie. „Building physical resource accounts for Namibia: depletion of water, minerals and fish stocks, and loss of biodiversity“. In Environmental Accounting in Theory and Practice, 171–86. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1433-4_11.
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Ericsson, Magnus, und Patrik Söderholm. „Mineral Depletion and Peak Production“. In Global Resources, 222–31. London: Palgrave Macmillan UK, 2013. http://dx.doi.org/10.1057/9781137349149_12.
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Mujais, Salim K. „Regulation of Renal Na-K-ATPase: Effects of Aldosterone in Phosphate Depletion“. In Phosphate and Mineral Homeostasis, 485–92. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-5206-8_60.
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Whitcomb, Sarah J., Elmien Heyneke, Fayezeh Aarabi, Mutsumi Watanabe und Rainer Hoefgen. „Mineral Nutrient Depletion Affects Plant Development and Crop Yield“. In Plant Ecophysiology, 205–28. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-10635-9_8.
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Kumar Samal, Sumant, Manoja Kumar Mohanty, Subash Chandra Mishra und Bhagiratha Mishra. „Plasma Processing of Iron Ore“. In Iron Ores [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94050.
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The depletion of high-grade ore minerals and the scarcity of fossil fuel reserves are challenging factors for metallurgical industries in the future. Also, extensive mining for increased steel demand results in the generation of fines often found unsuitable for use as direct feedstock for the production of metals and alloys. Apart from mines waste, the other major sources of fine minerals are leftover in charge burdens, sludges, and dust generated in the high-temperature process. Sludge and fines generated during beneficiation of ore add to this woe, as the outcomes of beneficiation plants for lean ores show better yield for fine particles. The utilization of lean ore and wastes in iron making requires wide research and adopting new advanced technologies for quality production with time-saving operations. The application of thermal plasma in mineral processing has several advantages that can overcome the current industrial metal extraction barriers. The present study demonstrates the thermal plasma for the processing of different iron-bearing minerals and its feasibility for metal extraction.
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Valero Delgado, A. „Mineral resource depletion assessment“. In Eco-efficient Construction and Building Materials, 13–37. Elsevier, 2014. http://dx.doi.org/10.1533/9780857097729.1.13.
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Bag, Surajit. „Identifying Green Supply Chain Management Enablers in South African Mining Industry using Ecological Modernization Theory Approach“. In Operations and Service Management, 452–76. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3909-4.ch022.
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Green supply chain management is a popular practice in any world class organization. The traditional supply chain was managed with the objectives to reduce cost without focusing on environmental and social dimensions. However with passage of time institutional pressures has directed firms to design supply chain network which takes care of environmental and social dimensions as well. Green supply chain management concept has evolved gradually over a period of time. The main reason behind evolution of green supply chain management is conservation of natural resources which human beings ignored for long. Published reports show that major portion of the energy is supplied by fossil fuels and thereby depletion of natural resources is occurring at an accelerating rate with time. Industrial manufacturing report also suggest that demand for manufacturing products is likely to double by the year 2050. This will result in high generation of pollutants and gases. If the greenhouse gases emissions remain unchecked, then it will create a catastrophic effect by 2050. Globally manufacturers and industry associations are now acting proactively to conserve the natural resources and curb greenhouse gases emissions. The level of popularity of green supply chain management can be estimated from the high research output in leading operations journals such as IJPE, IJPR, Resources, Conservation and Recycling Journals. Green supply chain management is a concept that is also gaining popularity in the South African region. For many organizations in this region it is a process to exhibit their sincere commitment to sustainability. However, if green supply chain management practices are to be fully adopted by all mining and minerals industry in South Africa, a demonstrable link between such measures and understanding the role of associated variables is necessary. This paper endeavors to develop a green supply chain management model for mining and minerals industry in the South African region. The approach extends the domain of green supply chain research and produce theories that have greater explanatory power than the current practices. For this purpose a conceptual model was developed from literature review and data collected using a structured questionnaire mailed to a sample of 174 firms which are leading edge ISO14001 certified mining companies in South Africa. Data analysis is further performed through exploratory factor analysis and regression analysis. This paper presents the first empirical evaluation of the link between green supply chain management practices amongst a sample of mining and minerals companies in South Africa.
Konferenzberichte zum Thema "Minerals Depletion"
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Kalugina, O. I., K. A. Shlyapina, E. R. Baranova und S. A. Simon. „CHEESE AS PREVENTION OF PROTEIN-ENERGY INSUFFICIENCY“. In I International Congress “The Latest Achievements of Medicine, Healthcare, and Health-Saving Technologies”. Kemerovo State University, 2023. http://dx.doi.org/10.21603/-i-ic-48.
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Protein-energy depletion (PEW) is the depletion of protein/energy reserves observed in the most advanced stages of chronic kidney disease (CKD). PEW is widespread among patients on chronic dialysis and is associated with adverse clinical outcomes, high morbidity/mortality rates and increased healthcare costs. Cheeses are characterized by a significant content of proteins, milk fat, as well as minerals. Cheese proteins are better absorbed in the human body, compared with dairy. Extractive elements of cheeses have a positive effect on the digestive glands, increase appetite. The nutrients contained in cheese are absorbed by the body almost completely.
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Valero, Alicia, Antonio Valero und Inmaculada Arauzo. „Exergy as an Indicator for Resources Scarcity: The Exergy Loss of Australian Mineral Capital — A Case Study“. In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-13654.
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Over the span of the 20th century, the global demand for metals and minerals has increased dramatically. This is associated with a general trend of declining ore grades from most commodities, meaning higher quantities of ore needed to be processed and thus more energy. Hence, quantifying the loss of mineral capital in terms of mass is not enough since it does not take into account the quality of the minerals in the mine. Exergy is a better indicator than mass because it measures at the same time the three features that describe any natural resource: quantity, composition and a particular concentration. For the sake of better understanding the exergy results, they are expressed in tons of Metal equivalent, tMe, which are analogously defined to tons of oil equivalent, toe. The aim of this paper is 1) to show the methodology for obtaining the exergy loss of mineral resources throughout a certain period of time and 2) to apply it to the Australian case. From the available data of production and ore grade trends of Australian mining history, the tons of Metal equivalent lost, the cumulative exergy consumption, the exergy decrease of the economic demonstrated reserves and the estimated years until depletion of the main base-precious metals are provided, namely: for gold, copper nickel, silver lead and zinc.
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Behera, Sushanta Kumar, S. Chakraborty und B. C. Meikap. „Upgradation of Low Grade Coal to High Quality Coal by Chemical Beneficiation Technique“. In ASME 2017 Power Conference Joint With ICOPE-17 collocated with the ASME 2017 11th International Conference on Energy Sustainability, the ASME 2017 15th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2017 Nuclear Forum. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/power-icope2017-3057.
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Low rank or grade coals (LGC) are widely distributed over the world. Coal plays a vital role in the global energy demand especially through power generation and it mitigates the energy poverty. The major challenges by the utility of coal as regarding to energy security, a risk of climate change, and increasing of the energy demands are the main portfolio to develop the advanced technology for coal beneficiation. The gradual depletion of high quality coal and cost effective which become a significant issue for power generation while the low grade coals were served as low cost fuel and as an alternative energy security issue. In current research the low grade coal (>35% ash) has been upgraded to higher grade (<10%) by chemical cleaning method. The low grade coal was selected from Mahanadi Coalfields Limited, Odisha, India. Each test was conducted of 50 g coal (250 μm particle size) with 40% NaOH at 100 °C for 3 h and followed with 20% of H2O2, H2SO4, HCl, and HF acids at similar conditions. The research study revealed that ash content (mineral matter) of coal is reduced to >70% by NaOH followed HF treatment as compared to other solvents. The greater liberation of mineral results increases the ash reduction from low grade coal because mineral associated in the coal matrix may formed elution by the leaching effect. The greater extent of demineralization was caused due to the high affinity of OH− and F− with minerals in the coal matrix. The characterization of pre and post treatment coal and coal ash was investigated by the FESEM, XRF and XRD analysis. Overall the current research study challenges the chemical cleaning of low grade coal has been efficient techniques for reducing the minerals to a certain limit.
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Hashemi, Sam S., Anthony R. Kovscek und Mark D. Zoback. „Effect of Supercritical CO2 on the Poroelastic Characteristics of Poorly Cemented Sandstone Reservoirs During Depletion and Injection“. In SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210228-ms.
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Abstract While there is continuing interest in geologic CO2 storage, experimental studies on poroelastic characteristics of reservoir rocks during depletion and subsequent CO2 injection are scarce. Rock stiffness, confining stress, and pore pressure control the poroelastic response of saturated rocks. Also, the stress and pore pressure evolution during injection is a key parameter to understanding operations thresholds for CO2 storage projects. As depleted fields in the Gulf of Mexico have been identified as strong candidates for CO2 storage projects, it is important to understand if the poroelastic characteristics from such fields have been altered due to depletion. Among rock properties, Young’s modulus (E), bulk modulus (Kb) and Biot coefficient (α) are of particular importance. In this study, the poroelastic deformation of a core from the West Delta field in the Gulf of Mexico is characterized experimentally and the impacts of supercritical CO2 (scCO2) on the specimen are investigated. The experimental program simulated reservoir stress changes due to production-induced depletion and scCO2 injection through cycling both the confining pressure (Cp) and pore pressure (Pp). We measured the deviatoric stress, volumetric strain, derived the corresponding Young’s (E), bulk moduli (Kb) and Biot coefficient (α). The results show that the effect of scCO2 on E is more significant at greater confining pressures during the injection phase than depletion at a constant simple effective stress. Interaction of scCO2 with clay minerals caused rock frame dehydration and led to an increase in E. The bulk modulus increased with increasing the confining pressure at a given Pp and decreased with Pp at a certain Cp. α rose with Pp during both depletion and injection phases. Interaction with scCO2 limited the variation of α and the effect of Pp and Cp on α decreased in significance during the depletion phase. Longer interaction time with scCO2 increased α from 10-25% at different Pp values compared to argon during the injection stage. However, the influence of effective stress in reducing the α weakened.
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May, Preston, Jay P. Deville und Jeffrey Miller. „Shale Inhibitor Tracking for High-Performance Water-Based Drilling Fluids“. In IADC/SPE International Drilling Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/208721-ms.
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Abstract Drilling wells with water-based fluid systems can be problematic due to the water reactivity of clay-containing shale minerals. This fundamental issue is the most often cited performance gap between non-aqueous fluid (NAF) and water-based fluids (WBF). The consequences of uncontrolled shale hydration include issues such as bit-balling/accretion, reduced ROP, wellbore collapse, and overall increased wellbore construction costs. This problem is typically addressed by the addition of shale inhibitors which can span multiple types of chemistries. The maintenance of these additives is nuanced due to their inherent depletion on reactive minerals leading to uncertainty of active concentration of these additives during a drilling campaign. Considering the critical need to maintain concentrations of these additives, uncertainty is not an optimal plan to ensure success. To this end, we have designed quantitative shale inhibitor tracking technology to measure amine-based shale inhibitors in high-performance water-based fluids. The method is robust, detects only amine-based swelling inhibitors, and is fully amenable to be performed at a rig site. We developed a colorimetric assay that quantitatively measures amine-based shale inhibitors in filtrates of WBFs. The reaction to generate color utilizes proprietary reagents that selectively target only the amines of interest, and is not influenced by nitrogen-containing polymers such as polyacrylamides. Additionally, the results of the test are not influenced by any common drilling fluid additives, including black powders. The colored solutions produced in the test are measured by advanced spectroscopic analysis with a handheld, portable field meter at a specific wavelength. The absorbance is used to determine the concentration of the amine inhibitor in the fluid filtrate. Finally, we have tested reliability of the method through numerous approaches including Gage Repeatability and Reproducibility statistical analysis. With this new technology, we have explored amine depletion on reactive clays in a lab setting, uncovering unique depletion rates based on amine chemistry. Additionally, we have trialed this technology in multiple wells. We have validated the test method and equipment to be field friendly and accurate, as designed. Our field engineers have included this new measurement alongside a typical mud check. In our validation trials we have already observed different depletion rates based on well and operational procedures for amine inhibitor maintenance, and conflicting values of measured concentrations and product concentration estimates based on calculations. We have coupled high-performance fluid design with shale inhibitor tracking technology to reduce the uncertainty of WBF chemical composition. This technology will allow us to sustain effective concentrations of high-performance additives and improve operational reliability throughout the wellbore construction process. Furthermore, this technology will allow more effective re-use of WBF, reducing the environmental impact of our fluids, and lowering well costs.
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Khramov, Dimitri, und Evgeny Barmatov. „Fate of Emulsifier in Invert Emulsion Drilling Fluids: Hydrolysis and Adsorption on Solids“. In SPE International Conference on Oilfield Chemistry. SPE, 2021. http://dx.doi.org/10.2118/204290-ms.
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Abstract Emulsifier concentration in SBM is an important factor of drilling fluid stability. Proper concentration of amidoamine emulsifier is imperative for controlling low fluid loss and maintaining emulsion stability. This study investigates the physical and chemical interactions between emulsifier and other additives and describes the processes by which emulsifier is depleted from the drilling fluid. Three main pathways of emulsifier consumption are identified: emulsifier adsorption on solids found in drilling fluids and low gravity solids (LGS), chemical degradation, and to stabilize the invert emulsion. Design of experiments model and analytical procedure based on 1H NMR (nuclear magnetic resonance) spectroscopy was used to quantify the required emulsifier concentration in Non-Aqueous Fluid system (NAF). Additionally, model systems were used to estimate the excess of emulsifier, evaluate the emulsifier losses due to alkaline hydrolysis at elevated temperature, and measure adsorption of emulsifier on barite and various LGS types. Calculations for emulsifier depletion based on model systems were correlated to performance of formulated drilling fluids for verification. Typical emulsifier requirement in high performance NAF is 8-12 pounds per barrel (ppb). Majority of the emulsifier is adsorbed on weighting agents (barite) and rheology modifiers (clays), which are used to formulate NAF, that contribute to their effective dispersion in the solution and control fluid rheology. The adsorption process is found to be sensitive to the emulsifier concentration, solids mineralogy, wetting agent and temperature. Analytical Langmuir-Freundlich isotherm was used to describe adsorption data and estimate the adsorption capacity of the system. The emulsifier degradation pathway is another important factor of emulsifier consumption; however, emulsifier degradation at 250°F is not significant. While NAF are generally run ‘rich’ to mitigate depletion and maintain fluid stability, adsorption onto minerals will become an issue especially at high LGS concentration. These results will be greatly beneficial in the further development of NAF drilling fluid formulations and will assist field engineers in understanding the effect excess emulsifier will have on the drilling fluid and enable them to more effectively control the fluid properties under variations in emulsifier and LGS concentration during drilling.
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Hu, Yisheng, Eric Mackay, Oleg Ishkov und Alistair Strachan. „Predicted and Observed Evolution of Produced Brine Compositions, and Implications for Scale Management“. In SPE International Oilfield Scale Conference and Exhibition. SPE, 2014. http://dx.doi.org/10.2118/spe-169765-ms.
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AbstractProduced water was sampled and measured repeatedly during production from an offshore field, and an extensive brine chemistry dataset was developed. Systematic analysis of this dataset enables an in-depth study of brine/brine and brine/rock interactions occurring in the reservoir, with the objective of improving the prediction and management of scale formation, prevention and remediation.A study of the individual ion trends in the produced brine, using the types of plot developed for the Reacting Ions Toolkit (Ishkov et al., 2009), provides insights into what components are involved in in situ geochemical reactions as the brines are displaced through the reservoir, and how the precipitation and dissolution of minerals and the ion exchange reactions occurring within the reservoir can be identified. This information is then used to better evaluate the scale risk at the production wells.A thermodynamic prediction model is used to calculate the risk of scale precipitation in a series of individual produced water samples, thus providing an evaluation of the actual scaling risk in these samples, rather than the usual theoretical estimate based on endpoint formation and injection brine compositions, and the erroneous assumption that no reactions in the reservoir impact the produced water composition. Nonetheless, the usual effects of temperature, pressure and brine composition are accounted for in these calculations using classical thermodynamics. The comparison of theoretical and actual results indicates that geochemical reactions taking place in this given reservoir lead to ion depletion that greatly reduces the severity and potential for scale formation. However, ion exchange reactions are also observed, and these too affect the scale risk, and the effectiveness of scale inhibitors in preventing deposition.Additionally, comprehensive analysis using a geochemical model is used to predict the evolution of the produced brine compositions at the production wells, and to test the assumptions about which in situ reactions are occurring. A good match between the predictions from this geochemical model and the observed produced brine compositions is obtained, suggesting that the key reactions included in the geochemical model are representative of actual field behaviour. This helps to establish confidence that the model can be used as a predictive tool.
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„Capturing Bio-Sensing Solutions: Biomonapp’s Story about the Seasons of Change across a Global Sustainable Landscape - Monitoring for Sustainable Bioremediation in Rural & Urban Farms, Soil, Agronomy, & Aquaculture“. In InSITE 2018: Informing Science + IT Education Conferences: La Verne California. Informing Science Institute, 2018. http://dx.doi.org/10.28945/4052.
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Aim/Purpose: This paper addressed the topics of sustainable agronomy, aquaculture, hydroponics and soil monitoring methods that show how to move towards a repairing mode and bioremediation in many locations across the globe. Background: Sixty percent of the world’s major terrestrial ecosystems are being degraded; the human ecological footprint is spreading across the globe. The major human impact on terrestrial ecosystems in the form of depletion of ground water, over grazing of livestock, clearing for agriculture, timber and urban development, soil damage from off road vehicles, hydroelectric dams and reservoirs, and air pollution from urban areas and power plants. The cost to bio remediate is in the trillions. Methodology: AG biotech methodologies and applications Contribution: The paper bridges such gaps and informs about brave entrepreneurs and university and community individuals with innovative ideas and emerging technologies that gain the momentum for funding and monitoring nutrient uptake and toxic removal of harmful chemicals from water, soil, plants and fish for restoration to take place. Such techniques begin to conquer the giant by restoring the wealth to our soils and water, rural and urban farmlands and forests that retain and capture natural capital and ensure that nutrition and value added resources minerals are not lost. Findings: Biomonapp can detect and make recommendations for repairing & making sustainable solutions, many entrepreneurs & academics have pioneered ways to find SUS solutions Recommendations for Practitioners: Read from the articles and books listed in the references of this paper to understand the need for bioremediation. Use Biomonapp to diagnose water, soil & fish problems & find solutions. Attend conferences & seminars about SUS responsibility & phytoremediation Recommendation for Researchers: To investigate the phytoremediation and bioremediation techniques. Applications for Biomonapp for plants, water, soil, & animals to rejuvenate and repair water, soil and urban & rural communities Impact on Society: These ideas give the power back to local people who can learn to enhance their lives not only by foods but the sustainable green jobs that are being created to make sure urban and rural areas truly are sustainable. Future Research: The results of monitoring with biosensors & bio monitoring methods with regards to sustainable bioremediation, renovating, continued SUS responsibility training, continued evidence of repair and protecting natural capital & ecosystem services
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Baburao, K., Daya Shukla und Nalin Nanavati. „Depletion rate of oxidation inhibitor in hydroprocessed mineral insulating oil and naphthenic oils“. In 2012 IEEE International Conference on Condition Monitoring and Diagnosis (CMD). IEEE, 2012. http://dx.doi.org/10.1109/cmd.2012.6416426.
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Sinha, Shailendra, und Avinash Kumar Agarwal. „Experimental Investigation of the Effect of Biodiesel Utilization on Lubricating Oil Degradation and Wear of a Transportation CIDI Engine“. In ASME 2007 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/icef2007-1721.
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Increased environmental awareness and depletion of fossil petroleum resources are driving industry to develop alternative fuels that are environmentally more acceptable. Biodiesel is an alternative fuel derived from vegetable oils by modifying its molecular structure. In the present experimental research work, methyl ester of rice-bran oil (ROME) is derived through transesterification of rice-bran oil using methanol in presence of sodium hydroxide (NaOH) catalyst. On the basis of previous research for performance, emission and combustion characteristics, a 20% blend of ROME (B20) was selected as optimum biodiesel blend. In the present research, the experimental investigation was aimed to investigate the effect of biodiesel on wear of in-cylinder components. Endurance tests were conducted on a medium duty direct injection transportation diesel engine with 20% blend of the ROME with mineral diesel. Tests were conducted under predetermined loading cycles in two phases: engine operating on mineral diesel and engine fuelled with 20% biodiesel blend. After completion of the tests, engines were dismantled for observing the physical condition of the various parts, e.g. piston rings, bearings, cylinder liner, cylinder head etc. Physical measurements of various vital parts were also carried out to assess the wear of the parts of engine. The physical wear of various parts except big end bearings were found to be lower in case of 20% biodiesel fuelled engine. Wear metals in the lubricating oil samples drawn from the engines at regular intervals were investigated. Relatively lower wear concentration of all wear metals except lead were found in the lubricating oil of B20 fuelled engine. Two quantify the wear of cylinder liners, surface parameters at different locations in the liner (TDC, BDC and mid-stroke) were measured and investigated. A qualitative analysis was also carried out by taking surface profiles and conducting scanning electron microscopy at same locations.
Berichte der Organisationen zum Thema "Minerals Depletion"
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Simandl, G. J., R. J. D'Souza, S. Paradis und J. Spence. Rare-earth element content of carbonate minerals in sediment-hosted Pb-Zn deposits, southern Canadian Rocky Mountains. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328001.
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Paleozoic platform carbonate rocks of the Rocky Mountains host Mississippi Valley-type (MVT), magnesite, barite, and REE-barite-fluorite deposits. Farther west, platform carbonate rocks of the Kootenay Arc host MVT and fracture-controlled replacement (FCR) deposits. This is the first systematic LA-ICP-MS study of carbonates in MVT and FCR deposits. We investigated seven MVT deposits in the Rocky Mountains, and five MVT deposits in the Kootenay Arc. None of the post-Archean Australian shale (PAAS)-normalized REE profiles show light REE (LREE) depletion and strong negative Ce anomalies characteristic of modern seawater: some profiles are nearly flat; others show depletion in LREE similar to seawater but without negative Ce anomalies; others are middle REE enriched. Carbonates with a strong positive Eu anomaly precipitated from or interacted with different fluids than carbonates with flatter profiles without a strong positive Eu anomaly. REE signatures reflect crystallization conditions of primary carbonates, and crystallization and re-equilibration conditions of carbonates with ambient fluids during diagenesis, deep burial, and/or metamorphic recrystallization. Chemical evolution of fluids along their migration path, fluid-to-rock ratio, fluid acidity, redox, and temperature also influence REE profile shape, which helps establish genetic and timing constraints on studied deposits and improves knowledge of the metallogeny of the Kootenay Arc and Rocky Mountains.