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Salt in the Earth
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Year: 2020 Publisher: London : IntechOpen,

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Abstract

Salt is a predominant compound for humankind and the earth preserves an important source of this element of life. This book reviews this multi-disciplinary issue in which geoscientists, historians, agriculturalists, medical doctors, and general scientists have been interested in its nature. The authors have provided contributions on the origin and history of salt, intrusion with freshwater effect, its usability as a material, and its role in life. The safety of groundwater resources should be a priority for humanity. Contribution on this important topic is provided by geophysical investigations to characterize saltwater intrusions in aquifers. This book also presents a general overview on salt intake and its role in food and human health. Methods of salt recovery and surface salination as well as its usage in the environment will provide new aspects in earth science.

Keywords

Salt.


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Spectroscopic ellipsometry of interfacial phase transitions in fluid metallic systems: KxKCl1-x and Ga1-xBix [online]
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Year: 2004 Publisher: KIT Scientific Publishing

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The investigation of the interfacial phase transitions in fluid systems with short-range intermetallic interactions are of great interest. The phenomena were studied in two systems exhibiting a liquid-liquid miscibility gap: at the fluid/wall interface in fluid KxKCl1-x and at the fluid/vacuum interface of the Ga1 xBix alloys. To characterize the interfacial changes of the ultra thin films (composition, thickness and their evolution with time) the spectroscopic ellipsometry was performed over a wide spectral range. Whereas in the experiments on KxKCl1-x an existing ellipsometer could be used, a completely new UHV-apparatus including the in-situ phase modulation ellipsometer had to be developed for Ga1 xBix alloys. For the KxKCl1-x system new results on complete wetting at solid-liquid coexistence as well as in the homogenous liquid phase (prewetting) are presented. The spectra show the typical F center absorption which indicates that the film is a salt-rich phase. The thickness strongly increases approaching the monotectic from 30 to 440 nm, which is in agreement with the tetra point wetting scenario. For this interpretation a quantitative description of the excess Gibbs energy has been developed. For the Ga1 xBix system the results on complete wetting, surface freezing and oscillatory interfacial instabilities are presented. The high-precision spectra have been recorded approaching the liquid-liquid miscibility. These spectra have been modeled using a Ga-Bi effective medium approximation for the substrate covered by a film of liquid Bi. The measurements give evidence of tetra point wetting in the Ga-Bi system. First ellipsometric study of the surface freezing in Ga-Bi has been performed. Within the miscibility gap a very interesting effect of surface and bulk oscillatory instability was observed. The details of this process at present are not well understood, but a qualitative description is given.


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Salt Taste, Nutrition, and Health
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Year: 2020 Publisher: Basel, Switzerland MDPI - Multidisciplinary Digital Publishing Institute

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Salt (NaCl) is a key component of the human diet because it provides the sodium ion (Na+), an essential mineral for our body. Na+ regulates extracellular fluid volume and plays a key role in many physiological processes, such as the generation of nerve impulses. Na+ is lost continuously through the kidneys, intestine, and sweating. Thus, to maintain proper bodily balance, losses have to be balanced with foods containing this cation. The need for salt explains our ability to detect Na+ in foodstuffs: Na+ elicits a specific taste sensation called “salty”, and gustatory sensitivity to this cation is crucial for regulating its intake. Indeed, the widespread use of salt in food products for flavoring and to improve their palatability exploits our sense of taste for Na+. When consumed in excess, however, salt might be detrimental to health because it may determine an increase in blood pressure—a major risk factor for many cardiovascular diseases. Understanding how salt taste works and how it affects food preference and consumption is therefore of paramount importance for improving human nutrition. This book comprises cutting-edge research dealing with salt taste mechanisms relevant for nutrition and health.

Salt and State : An Annotated Translation of the Songshi Salt Monopoly Treatise
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ISBN: 0892641630 0472901451 Year: 2004 Publisher: Ann Arbor : Center for Chinese Studies, University of Michigan,

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From its inception in the Han dynasty (206 B.C.-220 A.D.), the salt monopoly was a key component in the Chinese government's financial toolkit. Salt, with its highly localized and large-scale production, was an ideal target for bureaucratic management. In the Song dynasty (960-1279), fiscal pressures on the government had intensified with increased centralization and bureaucratization. A bloated administration and an enormous standing army maintained against incursions by aggressive steppe neighbors placed tremendous strain on Song finances. Developing the salt monopoly seemed a logical and indeed urgent strategy, but each actor in this plan -- the emperor, local officials, monopoly administrators, producers, merchants, and consumers -- had his own interests to protect and advance. Thus attempts to maximize the effectiveness of the monopoly meant frequent policy swings and led to levels of corruption that would ultimately undo the Song. Unlike other contemporary sources, the 'Songshi' treatise organizes its subject into an intelligible and detailed narrative, elucidating special terminology, the bureaucracy and its processes, and debates relating to Chinese finance and politics, as well as the salt industry itself. Professor Chien's extensive annotation relies on parallel histories that corroborate and supplement the 'Songshi' account, together providing a comprehensive study of this important institution in China's premodern political economy. Cecilia Chien is Assistant Professor in the Division of Humanities at the Hong Kong University of Science and Technology.


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Direct Radiative Effects of Sea Salt on the Regional Scale
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ISBN: 1000024937 3866447736 Year: 2011 Publisher: KIT Scientific Publishing

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This thesis aims to quantify the direct radiative effects of sea salt aerosol in the atmosphere. The online coupled regional scale model system COSMO-ART is extended for this objective with respect to the sea salt aerosol. Furthermore, a new sea salt optical parameterisation is developed for both the shortwave and longwave spectrum. Based on numerical simulations with the extended model system, the direct radiative effects of sea salt aerosol are investigated.


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Salinity Tolerance in Plants: Mechanisms and Regulation of Ion Transport
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Year: 2018 Publisher: Frontiers Media SA

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Life presumably arose in the primeval oceans with similar or even greater salinity than the present ocean, so the ancient cells were designed to withstand salinity. However, the immediate ancestors of land plants most likely lived in fresh, or slightly brackish, water. The fresh/brackish water origins might explain why many land plants, including some cereals, can withstand moderate salinity, but only 1 – 2 % of all the higher plant species were able to re-discover their saline origins again and survive at increased salinities close to that of seawater. From a practical side, salinity is among the major threats to agriculture, having been one of the reasons for the demise of the ancient Mesopotamian Sumer civilisation and in the present time causing huge annual economic losses of over 10 billion USD. The effects of salinity on plants include osmotic stress, disruption of membrane ion transport, direct toxicity of high cytoplasmic concentrations of sodium and chloride on cellular processes and induced oxidative stress. Ion transport is the crucial starting point that determines salinity tolerance in plants. Transport via membranes is mediated mostly by the ion channels and transporters, which ensure selective passage of specific ions. The molecular and structural diversity of these ion channels and transporters is amazing. Obtaining the detailed descriptions of distinct ion channels and transporters present in halophytes, marine algae and salt-tolerant fungi and then progressing to the cellular and the whole organism mechanisms, is one of the logical ways to understand high salinity tolerance. Transfer of the genes from halophytes to agricultural crops is a means to increase salt tolerance of the crops. The theoretical scientific approaches involve protein chemistry, structure-function relations of membrane proteins, synthetic biology, systems biology and physiology of stress and ion homeostasis. At the time of compiling this e-book many aspects of ion transport under salinity stress are not yet well understood. The e-book has attracted researchers in ion transport and salinity tolerance. We have combined our efforts to achieve a wider, more detailed understanding of salt tolerance in plants mediated by ion transport, to understand present and future ways to modify and manipulate ion transport and salinity tolerance and also to find natural limits for the modifications.


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Abiotic Stresses in Agroecology: A Challenge for Whole Plant Physiology
Authors: --- ---
Year: 2017 Publisher: Frontiers Media SA

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Understanding plant responses to abiotic stresses is central to our ability to predict the impact of global change and environmental pollution on the production of food, feed and forestry. Besides increasing carbon dioxide concentration and rising global temperature, increasingly frequent and severe climatic events (e.g. extended droughts, heat waves, flooding) are expected in the coming decades. Additionally, pollution (e.g. heavy metals, gaseous pollutants such as ozone or sulfur dioxide) is an important factor in many regions, decreasing plant productivity and product quality. This Research topic focuses on stress responses at the level of whole plants, addressing biomass-related processes (development of the root system, root respiration/fermentation, leaf expansion, stomatal regulation, photosynthetic capacity, leaf senescence, yield) and interactions between organs (transport via xylem and phloem, long-distance signaling and secondary metabolites). Comparisons between species and between varieties of the same species are helpful to evaluate the potential for species selection and genetic improvement. This research topic is focused on the following abiotic stresses and interactions between them: - Increased carbon dioxide concentration in ambient air is an important parameter influenced by global change and affects photosynthesis, stomatal regulation, plant growth and finally yield. - Elevated temperature: both the steady rise in average temperature and extreme events of shorter duration (heat waves) must be considered in the context of alterations in carbon balance through increased photorespiration, decreased Rubisco activation and carboxylation efficiency, damage to photosynthetic apparatus, as well as loss of water via transpiration and stomatal sensitivity. - Low temperatures (late frosts, prolonged cold phases, freezing temperature) can decrease overwintering survival rates, productivity of crop plants and species composition in meadows. - Water availability: More frequent, severe and extended drought periods have been predicted by climate change models. The timing and duration of a drought period is crucial to determining plant responses, particularly if the drought event coincides with an increase in temperature. Drought causes stomatal closure, decreasing the cooling potential of transpiration and potentially leading to thermal stress as leaf temperature rises. Waterlogging may become also more relevant during the next decades and is especially important for seedlings and young plants. It is not the presence of water itself that causes the stress, but the exclusion of oxygen from the soil which causes a decrease in respiration and an increase in fermentation rates followed by a period of potential oxidative stress as water recedes. - Salinity: high salt concentration in soil influences soil water potential, the water status of the plant and hence affects productivity. Salt tolerance will become an important trait driven by increased competition for land and the need to exploit marginal lands.


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Optimizing Miscanthus for the Sustainable Bioeconomy: From Genes to Products
Authors: --- ---
Year: 2018 Publisher: Frontiers Media SA

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In this Research Topic we report advances in fundamental and applied aspects of the perennial C4 bioenergy crop Miscanthus (Miscanthus spp.) and its role in mitigating climate change as part of the bioeconomy. Miscanthus is extremely well suited for bioenergy, biofuel and bioproduct production over a wide geographic area including Europe and North America as well as its native Asia.

Miscanthus offers a unique perspective within plant science: the challenge is to domesticate this novel crop for diverse environments and uses while simultaneously developing sustainable value chains to displace fossil fuels and contribute to climate change mitigation. Contributions to this Research Topic were offered from leading Miscanthus researchers from different parts of the world. We accepted 16 articles from 95 authors, which have generated 21,161 views at March 26 2018. Nine of the articles are the output of the European FP7 OPTIMISC project and describe multiple experiments investigating a common set of Miscanthus genotypes in Europe and Asia. These papers are complemented by seven additional articles from global authors, providing a comprehensive analysis of the state of the art of Miscanthus research and application.


Book
Bondgenoten in veiligheid : een programma voor ontwapening : het rapport van de Onafhankelijke commissie voor ontwapenings- en veiligheidsvraagstukken onder voorzitterschap van Olof Palme
Authors: ---
ISBN: 9021829606 Year: 1982 Publisher: Alphen aan den Rijn Sijthoff

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