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Microbial Connections Between the Subsurface Sulfur Cycle and Other Elemental Cycles

Authors: --- --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889456529 Year: Pages: 213 DOI: 10.3389/978-2-88945-652-9 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Microbiology --- Geography
Added to DOAB on : 2019-01-23 14:53:43
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Sulfur has many redox states and is a major metabolite in suboxic and anaerobic environments including, but not restricted to, marine and marginal marine sediments, the water column of oxygen minimum zones, salt marshes and oil wells. Microbially mediated redox cycling of sulfur typically comprises dissimilatory sulfate reduction (MSR), sulfide reoxidation, disproportionation and the oxidation and reduction of sulfur redox intermediates. These processes contribute to the degradation of organic matter, link the cycles of sulfur and carbon, control the production and consumption of methane and are critical for the long term budget of O2 in the atmosphere. Microbial and abiotic processes at redox interfaces also connect the sulfur cycle to the redox cycles of nitrogen, iron and other elements, producing distinctive geochemical and molecular signatures. Studies that couple microbiology with stable isotope geochemistry have informed interpretations of microbial sulfur cycling in modern and past environments. Laboratory-based studies and models of MSR have sought to understand the physiological and environmental controls of the magnitude of sulfur isotope fractionation. The fractionations of stable sulfur and oxygen isotopes during MSR are also used to track enzymatic activity during MSR and processes that oxidize sulfide in the presence of environmental oxidants. Outstanding questions in the field concern the importance of oxidative processes within the natural environment, the delivery of oxidants and carbon sources to the zones of sulfate reduction and the ability to detect or reconstruct oxidative processes from the chemical, isotopic, metagenomic, transcriptomic, proteomic and metabolomics profiles in the environment. Recent studies have emphasized the complex connections between sulfur and methane, iron, nitrogen and other elements. These links may involve the redox cycling of species that occur at concentrations difficult to detect by standard geochemical techniques or that are cycled at very rapid rates (cryptic cycles). Of particular interest is the use of isotope geochemistry to quantify links among various electron acceptors, including sulfate, ferric iron, and nitrate, during the anaerobic methane oxidation. For example, recent geochemical measurements have hinted that microbial sulfate reduction coupled to organic matter oxidation is mechanistically different to when sulfate reduction is coupled to methane oxidation. Recent studies have also suggested a possible contribution of a number of previously uncultured microbial groups in sulfur cycling in sulfidic environments, inspiring further studies of these organisms and their partnerships in anaerobic environments. This Research Topic highlights studies of microbial interactions, processes and communities that couple the sulfur cycle to the cycles of other elements in aphotic environments.

Sulfur-tolerant natural gas reforming for fuel-cell applications

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ISBN: 9783866444591 Year: Pages: II, 144 p. DOI: 10.5445/KSP/1000014763 Language: ENGLISH
Publisher: KIT Scientific Publishing
Subject: Chemical Engineering
Added to DOAB on : 2019-07-30 20:01:57
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An attractive simplification of PEM-FC systems operated with natural gas would be the use of a sulfur tolerant reforming catalyst, but such a catalyst has not been available thus far. In this work it is demonstrated that a tailor made rhodium catalyst retains useful activity for typical sulfur levels in the feed. A brief economic comparison showed however that this alternative process is still less economical than the traditional process employing removal of sulfur components by adsorption.

Elektrochemisches Verhalten von Lithium-Schwefel-Zellen mit unterschiedlicher Kathodenstruktur

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Book Series: Schriftenreihe des Instituts für Angewandte Materialien, Karlsruher Institut für Technologie ISSN: 21929963 ISBN: 9783731502968 Year: Volume: 46 Pages: IX, 183 p. DOI: 10.5445/KSP/1000044087 Language: GERMAN
Publisher: KIT Scientific Publishing
Subject: Technology (General)
Added to DOAB on : 2019-07-30 20:01:57
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The storage of energy is one main bottle-neck of the german energy transition. The lithium-sulfur battery with its high theoretical specific values can here play a major role. Depending on the composition and production of the cathode, the electrochemical characteristics of the battery vary greatly. In this work, the influence of the cathode structure and composition was analysed in terms of capacity and lifetime of lithium-sulfur cells.

Frontiers of Sulfur Metabolism in Plant Growth, Development, and Stress Response

Authors: --- --- --- --- et al.
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889199037 Year: Pages: 368 DOI: 10.3389/978-2-88919-903-7 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Botany
Added to DOAB on : 2016-01-19 14:05:46
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Growing plants have a constitutive demand for sulfur to synthesize proteins, sulfolipids and other essential sulfur containing molecules for growth and development. The uptake and subsequent distribution of sulfate is regulated in response to demand and environmental cues. The importance of sulfate for plant growth and vigor and hence crop yield and nutritional quality for human and animal diets has been clearly recognized. The acquisition of sulfur by plants, however, has become an increasingly important concern for the agriculture due to the decreasing S-emissions from industrial sources and the consequent limitation of inputs from atmospheric deposition. Molecular characterization involving transcriptomics, proteomics and metabolomics in Arabidopsis thaliana as well as in major crops revealed that sulfate uptake, distribution and assimilation are finely regulated depending on sulfur status and demand, and that these regulatory networks are integrated with cell cycle, photosynthesis, carbohydrate metabolism, hormonal signaling, uptake and assimilation of other nutrients, etc., to enable plant growth, development, and reproduction even under different biotic and abiotic stresses. This knowledge can be used to underpin approaches to enhance plant growth and nutritional quality of major food crops around the world. Although considerable progress has been made regarding the central role of sulfur metabolism in plant growth, development and stress response, several frontiers need to be explored to reveal the mechanisms of the cross-talk between sulfur metabolism and these processes. In this research topic the knowledge on plant sulfur metabolism is reviewed and updated. Focus is put not only on molecular mechanisms of control of sulfur metabolism but also on its integration with other vital metabolic events. The topic covers 4 major areas of sulfur research: sulfate uptake, assimilation and metabolism, regulation, and role in stress response. We hope that the topic will promote interaction between researchers with different expertise and thus contribute to a more integrative approach to study sulfur metabolism in plants.

Ethylene's Role in Plant Mineral Nutrition

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889199464 Year: Pages: 151 DOI: 10.3389/978-2-88919-946-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Botany
Added to DOAB on : 2016-01-19 14:05:46
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Terrestrial plants are sessile organisms that, differently from animals, can not move in searching of the nutrients and water they need. Instead, they have to change continuously their physiology and morphology to adapt to the environmental changes. When plants suffer from a nutrient deficiency, they develop physiological and morphological responses (mainly in their roots) aimed to facilitate the acquisition and mobilization of such a nutrient. Physiological responses include some ones like acidification of the rizhosphere and release of chelating agents into the medium; and morphological responses include others, like changes in root architecture and development of root hairs. The regulation of these responses is not totally known but in the last years different plant hormones and signaling substances, such as auxin, ethylene, cytokinins and nitric oxide, have been involved in their control. Besides hormones, oxidative stress has also been related with most of the nutrient deficiencies. The relationship of ethylene with the regulation of responses to nutrient deficiencies came from the nineties, when some works presented data suggesting its involvement in the regulation of responses to Fe and P deficiency. In the last years, the role of ethylene has been extended to many other nutrient deficiencies, such as K deficiency, Mg deficiency, S deficiency, N deficiency, and others. In most of the cases, it has been found that ethylene production, as well as the expression of ethylene synthesis genes, increases under these nutrient deficiencies. Furthermore, it has also been found that ethylene controls the expression of genes related to responses to different deficiencies. The involvement of ethylene in so many deficiencies suggests that it should act in conjunction with other signals that would confer nutrient-specificity to the distinct nutrient responses. These other signals could be plant hormones (auxin, cytokinins, etc) as well as other substances (nitric oxide, microRNAs, peptides, glutathione, etc), either originated in the roots or coming from the shoots through the phloem. The role of ethylene in the mineral nutrition of plants is even more complex that the one related to its role in the responses to nutrient deficiencies. Ethylene has also been implicated in the N2 fixation of legume plants; in salt tolerance responses; and in responses to heavy metals, such as Cd toxicity. All these processes are related to ion uptake and, consequently, are related to plant mineral nutrition. We consider a good opportunity to review all this information in a coordinated way. This Research Topic will provide an overview about the role of the plant hormone ethylene on the regulation of physiological and morphological responses to different nutrient deficiencies. In addition, it will cover other aspects of ethylene related to plant nutrition such as its role on salinity, N2 fixation and tolerance to heavy metals.

Keywords

Boron --- ethylene --- heavy metals --- Iron --- Nitrogen --- nodulation --- Phosphate --- Potassium --- Salinity --- Sulfur

Advances in Biogas Desulfurization

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ISBN: 9783039286607 / 9783039286614 Year: Pages: 106 DOI: 10.3390/books978-3-03928-661-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Biotechnology
Added to DOAB on : 2020-06-09 16:38:57
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Global concern about climate change caused by the exploitation of fossil fuels is encouraging the use of renewable energies. For instance, the European Union aims to be climate neutral by 2050. Biogas is an interesting renewable energy source due to its high calorific value. Today, biogas is mainly used for the production of electricity and heat by a combined heat and power engine. However, before its valorization, biogas needs to be desulfurized (H2S removal) to avoid corrosion and sulfur oxides emissions during its combustion. Biogas can be upgraded (CO2 removal) and used as vehicle fuel or injected into the natural gas grid. In the last 15 years, significant advances have occurred in the development of biological desulfurization processes. In this book with five chapters, the reader can find some of the latest advances in the biogas desulfurization and an overview of the state-of-the-art research. Three of them are research studies and two are reviews concerning the current state of biogas desulfurization technologies, economic analysis of alternatives, and the microbial ecology in biofiltration units. Biogas desulfurization is considered to be essential by many stakeholders (biogas producers, suppliers of biogas upgrading devices, gas traders, researchers, etc.) all around the world.

Wine Fermentation

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ISBN: 9783038976745 Year: Pages: 176 DOI: 10.3390/books978-3-03897-675-2 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Biotechnology --- Technology (General)
Added to DOAB on : 2019-04-05 11:07:22
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This book is a printed edition of the Special Issue Wine Fermentation that was published in Fermentation

Catalysts Deactivation, Poisoning and Regeneration

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ISBN: 9783039215461 9783039215478 Year: Pages: 254 DOI: 10.3390/books978-3-03921-547-8 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- Chemical Engineering
Added to DOAB on : 2019-12-09 11:49:15
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Catalyst lifetime represents one of the most crucial economic aspects in industrial catalytic processes, due to costly shutdowns, catalyst replacements, and proper disposal of spent materials. Not surprisingly, there is considerable motivation to understand and treat catalyst deactivation, poisoning, and regeneration, which causes this research topic to continue to grow. The complexity of catalyst poisoning obviously increases along with the increasing use of biomass/waste-derived/residual feedstocks and with requirements for cleaner and novel sustainable processes. This book collects 15 research papers providing insights into several scientific and technical aspects of catalyst poisoning and deactivation, proposing more tolerant catalyst formulations, and exploring possible regeneration strategies.

Keywords

hydrogenation --- copper --- catalyst --- water --- deactivation --- octanal --- octanol --- V2O5–WO3/TiO2 catalysts --- poisoning --- sulfur-containing sodium salts --- SO3 --- NO removal --- Cu/SSZ-13 --- NH3-SCR --- sodium ions --- deactivation mechanism --- sulfur poisoning --- coke deposition --- in situ regeneration --- Co-Zn/H-Beta --- NOx reduction by C3H8 --- catalyst deactivation --- diesel --- natural gas --- SEM --- TEM --- poisoning --- oxygen storage capacity --- thermal stability --- cyclic operation --- deactivation --- oxysulfate --- oxysulfide --- Selective Catalytic Reduction (SCR) --- SO2 poisoning --- Low-temperature catalyst --- nitrogen oxides --- nitrous oxide --- dry reforming of methane --- nickel catalysts --- barium carbonate --- deactivation by coking --- catalytic methane combustion --- exhaust gas --- catalyst durability --- Liquefied natural gas --- biogas --- vehicle emission control --- sulfur deactivation --- catalyst deactivation --- aluminum sulfate --- palladium sulfate --- regeneration --- phthalic anhydride --- vanadia-titania catalyst --- unusual deactivation --- physico-chemical characterization --- over-reduction --- vanadia species --- coke deposition --- DeNOx --- MW incinerator --- deactivation --- ammonium sulfates --- regeneration --- washing --- CO2 reforming --- Ni-catalyst --- syngas --- tetragonal zirconia --- phase stabilization --- CPO reactor --- effect of flow rate --- deactivation --- iso-octane --- Rh catalysts --- Rh --- homogeneous catalysis --- catalyst deactivation --- n/a

Metal Complexes Containing Boron Based Ligands

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ISBN: 9783039215843 9783039215850 Year: Pages: 110 DOI: 10.3390/books978-3-03921-585-0 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General) --- Inorganic Chemistry
Added to DOAB on : 2019-12-09 11:49:16
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Boron-based compounds have been utilized as ligands within transition metal complexes for many decades. The diversity of such compounds in terms of varying functional groups is truly exceptional. Boron compounds are of high interest due to the great potential to modify the substituents around the boron center and to produce a broad range of structural motifs. The many different ways these compounds can coordinate or interact with transition metal centers is astonishing. Examples of transition metal complexes containing boron-based ligands include scorpionates, cluster-type borane- and carboranes, borates, and phosphine-stabilized borylene ligands. This Special Issue brings together a collection of articles focusing on recent developments in the aforementioned boron-based ligands. The articles reported in this book will provide the reader with an overview of the types of boron-based ligands which are currently being researched in groups around the world.

Nutrition in Inflammatory Bowel Disease (IBD)

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ISBN: 9783039214396 9783039214402 Year: Pages: 370 DOI: 10.3390/books978-3-03921-440-2 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Nutrition and Food Sciences
Added to DOAB on : 2019-12-09 11:49:15
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The purpose of this Special Issue “Nutrition in Inflammatory Bowel Disease (IBD)” is to increase knowledge regarding the role of dietary composition and effects in IBD, describing the prevalence of malnutrition in IBD and the effect on clinical outcomes, discussing methods of nutrition risk screening and assessment in IBD, and reviewing mechanisms through which diet and dietary components may affect disease severity. The articles focus on the following areas: Dietary Composition/Therapy Interventions in Ulcerative Colitis and effects on outcomes; Dietary Composition/Therapy Interventions in Crohn’s Disease and effects on outcomes; Nutrition Risk Screening and Assessment in IBD; Mechanisms of Diet in the pathogenesis of IBD.

Keywords

body composition --- obesity --- visceral adipose tissue --- fat --- osteoporosis --- osteopenia --- sarcopenia --- inflammatory bowel disease --- Crohn’s disease --- dietary intake --- malnutrition --- Mediterranean diet --- exclusive enteral nutrition --- children --- IBD --- remission --- mucosal cytokines --- dietary protein level --- colitis --- epithelial repair --- mucosa-adherent microbiota --- intestinal inflammation --- inflammatory bowel disease --- epithelial adherens junctions --- bioactive peptides --- synbiotic --- prebiotic --- probiotic --- IBD --- Bacillus spores --- dietary fibre --- sugar cane fibre --- ulcerative colitis --- colon --- high-sulfur foods --- inflammation --- metagenomics --- microbiota --- sulfur reducing --- inflammatory bowel disease --- Crohn --- ulcerative colitis --- diet --- nutrition --- exclusive enteral nutrition --- intestinal epithelial cells --- inflammation --- probiotics --- Lactobacillus acidophilus --- Bifidobacterium animalis subsp. lactis --- vitamin D --- IBD --- Crohn’s disease --- ulcerative colitis --- supplementation --- deficiency --- Inflammatory Bowel Disease (IBD) --- Mediterranean Diet --- Western-style Diet (WSD) --- Nutritional Approach --- vitamin D --- Crohn’s disease --- ulcerative colitis --- faecal calprotectin --- C-reactive protein --- diet --- inflammatory bowel disease --- microbiota --- intestinal barrier --- nutrients --- immunity --- colitis --- food additive --- diet --- emulsifiers --- high salt diet --- inflammatory bowel diseases --- inflammatory bowel disease --- dietary modification --- exclusive enteral nutrition --- lifestyle modification --- Mediterranean diet --- colorectal cancer --- inflammatory bowel disease --- colorectal cancer --- dysplasia --- berries --- chemoprevention --- Inflammatory Bowel Disease --- micronutrients --- vitamin --- mineral --- deficiency --- inflammatory bowel disease --- dietary habits --- food components --- gut microbiota --- immune homeostasis --- epigenetic changes --- inflammatory bowel disease --- malnutrition --- Mediterranean diet --- older age --- diet --- inflammatory bowel disease --- ulcerative colitis --- inflammatory bowel disease --- Westernisation --- genotypes --- nutrient deficiency --- food intolerance --- FODMAPs --- gluten --- fructose --- lactose --- brassica --- mushrooms --- n/a

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