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Nucleation of Minerals: Precursors, Intermediates and Their Use in Materials Chemistry

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ISBN: 9783038970354 9783038970361 Year: Pages: X, 236 Language: english
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Environmental Sciences
Added to DOAB on : 2018-08-09 13:19:56
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Nucleation is the key event in mineralisation, but a general molecular understanding of phase separation mechanisms is still missing, despite more than 100 years of research in this field. In recent years, many studies have highlighted the occurrence of precursors and intermediates, which seem to challenge the assumptions underlying classical theories of nucleation and growth. This is especially true for the field of biomineralisation, where bio-inspired strategies take advantage of the special properties of the precursors and intermediates for the generation of advanced materials. All of this has led to the development of "non-classical" frameworks, which, however, often lack quantitative expressions for the evaluation and prediction of phase separation, growth and ripening processes, and are under considerable debate. It is thus evident that there is a crucial need for research into the early stages of mineral nucleation and growth, designed for the testing, refinement, and expansion of the different existing notions. This Special Issue of Minerals aims to bring together corresponding studies from all these areas, dealing with precursors and intermediates in mineralisation with the hope that it may contribute to the achievement of a better understanding of nucleation precursors and intermediates, and their target-oriented use in materials chemistry.

Enamel Research: Mechanisms and Characterization

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889450190 Year: Pages: 130 DOI: 10.3389/978-2-88945-019-0 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Physiology
Added to DOAB on : 2018-02-27 16:16:44
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The rodent incisor is a good model system to study the molecular and cellular events that are involved in enamel biomineralization. Incisors in rodents continuously erupt during their lifespan, thus allowing the study of all stages of enamel synthesis, deposition, mineralization and maturation in the same tissue section. This model system has provided invaluable insight into the specifics of enamel formation as a basis to understand human pathologies such as amelogenesis imperfect. Furthermore, the rodent incisor allows exploration and understanding of some of the most fundamental mechanisms that govern biomineralization. Enamel is the most mineralized, hardest tissue in the body. It is formed within a unique organic matrix that, unlike other hard tissues such as bone and dentin, does not contain collagen. The formation of enamel can be divided into two main stages: the secretory and maturation stage. During the secretory stage, a highly ordered arrangement of hydroxyapatite crystals is formed under the influence of structural matrix proteins such as amelogenin, ameloblastin and enamelin. During the maturation stage, the organic matrix is removed and hydroxyapatite crystals expand to ultimately yield a functional hard structure consisting of over 96% mineral. Research efforts over the past decades have mainly focused on the secretory stage, providing novel insights into the concept of biomineralization. However, the events that occur during the maturation stage have not been yet explored in detail, likely because the physiological roles of the enamel-forming ameloblasts are more diverse and complex at this stage. Mature ameloblasts are involved in the regulation of calcium transport in large amounts, phosphate and protein fragments in and out of the maturing enamel and provide regulatory mechanisms for the control of the pH. In recent years, increased efforts have been dedicated towards defining the molecular events during enamel maturation. The development of an ever-increasing number of transgenic animal models has clearly demonstrated the essential roles of matrix and non-matrix proteins during enamel formation. Multiple traditional and modern analytical techniques are applied for the characterization of enamel in these animals. The need for this Research Topic therefore stems from new information that has been generated on molecular events during the enamel maturation stage and the development and application of highly advanced analytical techniques to characterize dental enamel. The benefits and limitations of these techniques need to be reviewed and their application standardized for valid comparative studies.

Organogenesis From Development to Disease

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453184 Year: Pages: 110 DOI: 10.3389/978-2-88945-318-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Biology
Added to DOAB on : 2018-11-16 17:27:07
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During embryonic development there are many processes that must take place to produce a viable and healthy fetus. Alterations in the cellular and/or molecular interactions within any particular organ can cause catastrophic defects leading to defective organogenesis and death of the embryo. Even slight malformations of the organs can cause developmental reprogramming and increase the likelihood of adult onset diseases. The use of experimental animals with genetic mutations that mimic many human conditions has lead to significant scientific advancement of these complex and multifaceted diseases. Furthermore, the utilization of organ culture systems has made for profound insights into the formation of organs. Over recent years, the technology related to molecular profiling and imaging of developing organs has dramatically improved, leading to the identification of subtle genetic and phenotypic alterations. This research topic will focus on the area of organ formation and modeling of human developmental diseases.

Structural Control of Mineral Deposits. Theory and Reality

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ISBN: 9783038977841 / 9783038977858 Year: Pages: 256 DOI: 10.3390/books978-3-03897-785-8 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General)
Added to DOAB on : 2019-06-26 10:09:00
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""Structural Control"" remains a crucial point that frequently lacks in any scientific and/or economic analysis of ore deposits, whatever their type and class. The case of lode deposits is exemplary, although also other deposits, like breccia pipe, stockwerk, massive sulphides, skarn, etc., can, surprisingly, be concerned. Several concepts like the gold-bearing shear zone have not proven valid during the last few decades in terms of our understanding of gold deposit and have been totally abandoned. Additionally, the relationships between magmatism, regional tectonic context, and mineralization remain uncertain and have been debated in several recent publications. This demonstrates that this issue is still relevant, and its solution may help in the distinction between intrusion-related and orogenic deposits. In this Special Issue, we particularly invite any case study of mineral deposits, in which it has been demonstrated that structural geology may have a significant role in the establishment of the deposit model of formation and/or on exploration and exploitation programs. Examples in which the structural model diverges from those described in the classical literature are particularly welcomed, including studies in which relationships with magmatism can be suspected and/or demonstrated. Indeed, all cases that illustrate concepts that differ from the classic ones and from theoretical models may represent significant contributions to this volume.

Polymetallic Metallogenic System

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ISBN: 9783039212934 / 9783039212941 Year: Pages: 538 DOI: 10.3390/books978-3-03921-294-1 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General)
Added to DOAB on : 2019-12-09 16:10:12
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Within the last decade, the high and continuing demand for precious and base metals, as well as critical elements, has prompted a global rush on a scale never before seen. This eventually resulted in the demand for considerable innovation and improvement in mineral deposit genetic modelling and ore formation regimes for the many different types of gold deposits, now recognized, and paralleled by the wide employment of exploration techniques and a rapid expansion of geological databases. This Special Issue will show case studies of porphyry polymetal systems, orogenic gold formations, water–rock reaction, ore-forming structure evolution, mineralogy and petrology of ore deposit, ore formation regime, geochronology and geochemistry of ore deposit, ore-forming evolution, mineral exploration and cutting-edge technology in ore deposit study.

Keywords

W–Sn skarn --- whole-rock geochemistry --- Huangshaping --- Shizhuyuan --- Xianghualing --- Rare-Earth Elements --- C–O isotopes --- hydrothermal calcite --- ore-forming processes --- Phapon gold deposit --- oxidation state --- hydrous melts --- constraints on mineralization --- Beiya Au deposit --- SW China --- zircon geochronology --- magmatic oxygen fugacity --- petrogenesis --- Zaozigou deposit --- West Qinling --- archean basement --- quartz vein --- hydrothermal alteration halo --- Pinglidian gold deposit --- Jiaodong --- geochemistry --- U–Pb zircon age --- Sr–Nd isotopes --- Haoyaoerhudong gabbro --- Inner Mongolia --- geochronology --- Hf isotopes --- petrogenesis --- paleo-Tethyan ocean closure --- Zaorendao gold deposit --- West Qinling --- syenite --- post-collisional --- niobium mineralization --- Saima deposit --- Liaoning Province --- invisible gold --- visible gold --- LA-ICP-MS --- Yangshan gold belt --- West Qinling --- zircon U-Pb dating --- molybdenite Re-Os dating --- zircon Hf isotopes --- Weilasituo Sn-polymetallic deposit --- Inner Mongolia --- orogenic-gold deposit --- mineral geo-thermometry --- physicochemical condition of mineralization --- Zhengchong gold deposit --- Jiangnan orogenic belt --- lithospheric architecture --- metallogenesis --- Hf-Nd isotopic mapping --- Liaodong Peninsula --- North China Craton --- zircon U–Pb geochronology --- Sr–Nd–Pb–Hf isotopes --- low Sr and high Yb A2-type granite --- Xianghualing --- South China --- fluid inclusion --- stable isotopes --- gold deposition --- Sanshandao gold deposit --- Jiaodong --- fluid inclusions --- H–O isotope --- immiscibility --- water–rock interaction --- Sizhuang gold deposit --- Jiaodong Peninsula --- China --- Pulang porphyry Cu (–Mo–Au) deposit --- LA-ICP-MS zircon U–Pb dating --- molybdenite Re–Os dating --- high-silica adakitic rocks (HSA) --- Northwestern Yunnan Province --- C–H–O isotopes --- fluid inclusion --- Koka deposit --- orogenic gold deposit --- ore shoots --- structural control --- geostatistics --- Sizhuang gold deposit --- Jiaodong Peninsula --- skarn mineralogy --- high fugacity --- garnet Sm–Nd dating --- Late Cretaceous --- Hongshan skarn deposit --- mantle branch --- metallogenesis --- ore-controlling structures --- metallogenic rule --- ore prospecting target --- Jiaodong area --- zircon U–Pb dating --- Re–Os dating --- middle–late Jurassic --- Mo-polymetallic deposit --- Great Xing’an Range --- Dongbulage --- A-type granite --- tin mineralization --- Tiantangshan tin polymetallic deposit --- SE China --- Chishan alkaline complex --- rock geochemistry --- zircon U–Pb dating --- Lu–Hf isotopes --- Hegenshan-Heihe suture zone --- Cu-Au hydrothermal mineralization --- Hongyan deposit --- Permian A-type granite --- granite petrogenesis --- magmatic oxygen fugacity --- post-collisional slab break-off --- quartz --- trace element --- precipitation mechanism --- in situ study --- sericite --- acidity --- formation temperature --- n/a

Arctic Mineral Resources. Science and Technology

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ISBN: 9783038978244 9783038978251 Year: Pages: 432 DOI: 10.3390/books978-3-03897-825-1 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General)
Added to DOAB on : 2019-04-25 16:37:17
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The Arctic zone of the Earth is a major source of mineral and other natural resources for the future development of science and technology. It contains a large supply of strategic mineral deposits, including rare earths, copper, phosphorus, niobium, platinum-group elements, and other critical metals. The continued melting of the sea ice due to climate change makes these resources more accessible than ever before. However, the mineral exploration in the Arctic has always been a challenge due to the climatic restrictions, remote location, and vulnerability of Arctic ecosystems. This book covers a broad range of topics related to the problem of Arctic mineral resources, including geological, geochemical, and mineralogical aspects of their occurrence and formation; chemical technologies; and environmental and economic problems related to mineral exploration. The contributions can be tentatively classified into four major types: geodynamics and metallogeny, mineralogy and petrology, mineralogy and crystallography, and mining and chemical technologies associated with the exploration of mineral deposits and the use of raw materials for manufacturing new products. The book can be of interest for all those interested in Arctic issues and especially in Arctic mineral resources and associated problems of mineralogy, geology, geochemistry, and technology.

Keywords

forsterite --- typochemistry --- crystal structure --- Kovdor phoscorite–carbonatite complex --- pyrochlore supergroup minerals --- typochemistry --- crystal structure --- Kovdor phoscorite-carbonatite complex --- pyrrhotite --- chalcopyrite --- pentlandite --- cobaltpentlandite --- typochemistry --- crystal structure --- Kovdor phoscorite-carbonatite complex --- shkatulkalite --- titanosilicate --- crystal structure --- Kola Peninsula --- Lovozero alkaline massif --- transformation mineral species --- vuonnemite --- titanium --- niobium --- heap leaching --- bacterial leaching --- cryomineralogenesis --- low-grade copper-nickel ore --- raw materials --- apatite-nepheline-titanite ore --- sulfuric-acidic decomposition --- titanyl sulfate --- hydrothermal synthesis --- ivanyukite --- batievaite-(Y) --- hainite-(Y) --- titanosilicate --- rinkite group minerals --- Kola Peninsula --- Sakharjok massif --- Keivy alkaline province --- transformation mineral species --- vanadium mineralization --- mineralogy --- Paleoproterozoic --- Kola region --- Arctic zone --- Fennoscandian Shield --- zircon --- macrocrysts --- kimberlite --- trace elements --- geochronology --- cathodoluminescence --- Ti-in-zircon geothermometry --- antigorite --- ore dressing tailings --- mechanical activation --- alkali-activated binder --- Yenisei-Khatanga basin --- Siberian craton --- Arctic --- oil --- gas --- petroleum potential --- geodynamics --- apatite --- Khibiny --- apatite-nepheline deposit --- phase diagram apatite-nepheline-diopside --- silicocarbonatite --- melteigite --- calcite --- nepheline --- zeolite group minerals --- garnet --- crystal fractionation --- Breivikbotn --- Northern Norway --- saponite-containing waters --- diamond processing plants --- cryogenic treatment --- electrochemical separation --- saponite product applications --- U mineralization --- hydrothermal deposits --- U-Pb --- Rb-Sr --- Kola region --- evolution of the composition --- basic rocks --- Precambrian --- search of trend differences --- geodynamic evolution --- metallogeny --- beryllium minerals --- chemical composition --- mineral data --- alkaline rocks --- granite --- pegmatites --- hydrothermal veins --- Kola Peninsula --- Plume --- LIP --- PGE --- Palaeoproterozoic --- mafic intrusion --- U-Pb --- isotopes --- PGE --- South Reef --- West-Pana intrusion --- Fedorova-Pana Complex --- zircon dating --- U-Pb --- Khibiny promising structures --- conductive layers --- MHD-source “Khibiny”, Pechenga structure --- Kola Peninsula --- greenstone belt --- gold --- Kola Peninsula --- Northern Karelia --- rock alteration --- n/a

New Results and Advances in PGE Mineralogy in Ni-Cu-Cr-PGE Ore Systems

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ISBN: 9783039217168 / 9783039217175 Year: Pages: 228 DOI: 10.3390/books978-3-03921-717-5 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General)
Added to DOAB on : 2019-12-09 16:39:37
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The book (Special Issue) presents impressive new results related to a wide spectrum of occurrences of platinum-group minerals (PGM) and natural compounds enriched in platinum-group elements (PGE), which are associated with various complexes and deposits, such as Uralian-Alaskan-type complexes, layered intrusions and placers. The geographical locations of the involved deposits and complexes include, on a truly international scale, different areas of the Urals, Western and Eastern Sayans and Gornaya Shoria in Siberia, Southern Central Asian Orogenic Belt in China, Northern Michigan, USA, South Africa and Zimbabwe, etc. Of particular interest is the first description of a new species of PGM, thalhammerite (approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association), which is a new species of palladium-silver sulfobismuthide discovered in the Noril’sk region of Russia. Additionally, comprehensive reviews, on compositional variations in Pt–Fe alloy minerals and processes of transformations of PGM in exogenic environments, are presented which will also attract attention from international readers.

Keywords

platinum-group elements --- platinum-group minerals --- PGE alloys --- chromian spinel --- schemes of substitution --- Ti- and REE-rich inclusions --- Sisim placer zone --- Lysanskiy complex --- Eastern Sayans --- Russia --- platinum-group elements --- gold --- platinum-group minerals --- placer deposits --- ophiolite complexes --- western Sayans --- Russia --- thalhammerite --- platinum-group mineral --- Pd9Ag2Bi2S4 phase --- reflectance data --- X-ray-diffraction data --- crystal structure --- Komsomolsky mine --- Talnakh deposit --- Noril’sk region --- Russia --- chromitite --- platinum group minerals --- primary inclusions --- ophiolite --- Alaskan-type complex. --- Urals --- Russia --- Alaskan-type complex --- Central Asian Orogenic Belt --- PGM --- PGE mineralization --- Bushveld Complex --- South Africa --- Great Dyke --- Zimbabwe --- platinum-group minerals --- primary ores --- oxide ores --- placers --- allogenic --- authigenic --- Echo Lake --- Midcontinent --- palladium --- platinum --- magnetite --- gabbro --- platinum-group elements --- platinum-group minerals --- Pt–Fe alloys --- compositional variations --- element substitutions --- placer deposits --- ore mineralization --- ultramafic-mafic complexes --- Ural Platinum belt --- Ural-Alaskan massif --- Svetloborsky massif --- placer system --- platinum group elements --- platinum group minerals --- platiniferous tetra-auricupride --- Pt-for-Au substitution --- platinum --- gold --- ophiolite --- Bolshoy Khailyk placer --- western Sayans --- Russia --- platinum-group elements --- gold --- platinum-group minerals --- placer deposits --- micrometric inclusions --- Gornaya Shoria --- Siberia --- Russia --- n/a

Plasma Catalysis

Author:
ISBN: 9783038977506 Year: Pages: 246 DOI: 10.3390/books978-3-03897-751-3 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Chemical Engineering --- Technology (General)
Added to DOAB on : 2019-04-05 10:34:31
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Plasma catalysis is gaining increasing interest for various gas conversion applications, such as CO2 conversion into value-added chemicals and fuels, N2 fixation for the synthesis of NH3 or NOx, methane conversion into higher hydrocarbons or oxygenates. It is also widely used for air pollution control (e.g., VOC

Bioactive and Therapeutic Dental Materials

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ISBN: 9783039214198 / 9783039214204 Year: Pages: 216 DOI: 10.3390/books978-3-03921-420-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Chemistry (General)
Added to DOAB on : 2019-12-09 11:49:15
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This book focus principally on ions-releasing and other smart dental materials for application in preventive and restorative dentistry, as well as in endodontics in the form of adhesives, resin-based composites, pastes, varnishes, liners and dental cements. Special attention has been given to bioactive materials developed to induce cells differentiation/stimulation, hard tissue formation and exert antimicrobial actions. New innovations are necessary to continue to help reinforcing existing technologies and to introduce new paradigms for treating dental disease and restoring teeth seriously compromised by caries lesions via biomimetic and more biological operative approaches. Dental bioactive materials is arguably the latest research area in dentistry and thus the amount of new research is overwhelming. However, in this day and age of evidence based practice it important for this new information to be distilled into a practical and understandable format.

Keywords

orthodontic resin --- photocatalyst TiO2 --- antibacterial --- cariogenic --- early colonizer --- hydrophilic properties --- irradiation --- calcium silicate cements --- pulpal response --- mineralization --- calcific barrier --- inflammation --- odontoblastic layer --- resin cements --- shrinkage stress --- water sorption --- hydroscopic expansion --- photoelastic investigation --- antibacterial --- calcium --- doxycycline --- nanoparticles --- zinc --- dental composites --- antibacterial properties --- silver --- mechanical properties --- degree of conversion --- sorption --- solubility --- color stability --- mechanical properties --- nanotubes --- resin composite --- Streptococcus mutans --- triclosan --- bleaching products --- diffusion --- cytotoxicity --- dental pulp --- stem cells --- nanoporous silica --- glass-ionomer cement --- calcium --- preclinical biosafety --- bone substitute --- mesenchymal stem cells --- ?-tricalcium phosphate --- tissue engineering --- dental sealant --- resin sealant --- calcium phosphate nanoparticles --- long-term ion release --- remineralization --- ion recharge --- dentin --- desmineralization --- microtensile bond strength --- adhesion --- bioactive --- cycling mechanical stress --- dentine --- longevity --- resin-modified glass ionomer cements --- polyacrylic acid treatment --- bone regeneration --- ?-tricalcium phosphate --- calcium sulfate --- bone substitutes --- animal study --- n/a --- adhesion --- cycling mechanical stress --- dentine --- longevity --- glass-ionomer cements --- universal adhesives

Fertilizer Application on Crop Yield

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ISBN: 9783038976547 Year: Pages: 252 DOI: 10.3390/books978-3-03897-655-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Agriculture (General) --- Biology --- Science (General)
Added to DOAB on : 2019-04-05 10:34:31
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Abstract

This book is a printed edition of the Special Issue Fertilizer Application on Crop Yield that was published in Agronomy

Keywords

soil organic matter --- soil biota --- soil acidity --- soil erosion --- fertilizer management --- site-specific nutrient management --- balanced use of fertilizers --- integrated nutrient management --- agronomic response --- calcium --- Copper --- NPK amendments --- Value Cost Ratio --- Zinc --- nitrogen use efficiency (NUE) --- nitrate assimilation --- nitrate reductase activity --- maize --- nitrate --- ammonia --- NADH --- NADH-dehydrogenase --- Complex I --- site-specific K management --- soil K supply --- maize yield response to K --- maize crop manager --- nutrient expert for maize --- durum wheat --- mineral N --- organic N --- S fertilization --- grain quality --- grain yield --- phosphorous --- potassium --- corn–soybean rotation --- management --- production system --- organic farming --- conventional farming --- organic nutrients --- chemical fertilizers --- global food demand --- agroforestry system --- evergreen agriculture --- biofertilizer --- Bacillus pumilus --- growth promotion --- N fertilizer --- rice --- yield --- green manure --- nitrogen uptake --- Orychophragmus violaceus L. --- soil nitrogen pools --- grain yield --- Zea mays L. --- hybrid rice --- K use efficiency --- potassium --- saline tract --- soil N supply --- soil N mineralization --- N fertilization --- potentially mineralizable N --- humid Mediterranean climate --- conservation agriculture --- NUE --- nitrogen recovery efficiency --- nitrogen physiological recovery --- wheat yields --- Agrotain® urea --- rice-wheat system --- organic farming --- forage legume --- long-term productivity --- soil health --- economics --- integrated nutrient management --- rice --- wheat --- yield --- net returns --- soil health --- sustainability

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