Silicon Cycling in Soils Revisited
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Sodium Silicate Crops
Sodium Silicate Crops 1 Identification of Petitioned Substance 2 3 Chemical Names: CAS Numbers: 4 Sodium Silicate 1344-09-8 5 6 Other Name: Other Codes: 7 Sodium metasilicate; Sodium silicate glass; EPA PC code: 072603 (NLM, 2011a); European 8 Sodium water glass; Silicic acid, sodium salt; Inventory of Existing Commercial Chemical 9 tetrasodium orthosilicate (IPCS, 2004) Substances (EINECS) Number: 215-687-4 (IPCS, 10 2004) 11 Trade Names: 12 Waterglass, Britesil, Sikalon, Silican, Carsil, 13 Dryseq, Sodium siloconate, Star, Soluble glass, 14 Sodium polysilicate (NLM, 2011a), N® - PQ 15 Corporation (OMRI, 2011) 16 Characterization of Petitioned Substance 17 18 Composition of the Substance: 19 The basic formula of sodium silicate is Na2O· nO2Si, which represents the components of silicon dioxide (SiO2) 20 and sodium oxide (Na2O) and the varying ratios of the two in the various formulations. This ratio is commonly 21 called the molar ratio (MR), which can range from 0.5 to 4.0 for sodium silicates and varies depending on the 22 composition of the specific sodium silicate. The structural formulas of these silicates are also variable and can be 23 complex, depending on the formulation, but generally do not have distinct molecular structures (IPCS, 2004). 24 The basic structure of soluble silicates, including sodium and potassium silicates, is a trigonal planar 25 arrangement of oxygen atoms around a central silicon atom, as depicted in Figure 1 below. Physical and 26 chemical properties of sodium silicate are summarized in Table 1, on page 2. 27 28 29 30 31 32 33 34 35 Figure 1: Chemical Structure of Sodium Silicate (NLM, 2011a) 36 37 Specific Uses of the Substance: 38 39 Sodium silicate and other soluble silicates have been used in many industries since the early 19th century. -
Four Hundred Million Years of Silica Biomineralization in Land Plants
Four hundred million years of silica biomineralization in land plants Elizabeth Trembath-Reicherta,1, Jonathan Paul Wilsonb, Shawn E. McGlynna,c, and Woodward W. Fischera aDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125; bDepartment of Biology, Haverford College, Haverford, PA 19041; and cGraduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji-shi, Tokyo 192-0397, Japan Edited by Thure E. Cerling, University of Utah, Salt Lake City, UT, and approved February 20, 2015 (received for review January 7, 2015) Biomineralization plays a fundamental role in the global silicon Silica is widely used within plants for structural support and cycle. Grasses are known to mobilize significant quantities of Si in pathogen defense (19–21), but it remains a poorly understood the form of silica biominerals and dominate the terrestrial realm aspect of plant biology. Recent work on the angiosperm Oryza today, but they have relatively recent origins and only rose to sativa demonstrated that silica accumulation is facilitated by taxonomic and ecological prominence within the Cenozoic Era. transmembrane proteins expressed in root cells (21–24). Phy- This raises questions regarding when and how the biological silica logenetic analysis revealed that these silicon transport proteins cycle evolved. To address these questions, we examined silica were derived from a diverse family of modified aquaporins that abundances of extant members of early-diverging land plant include arsenite and glycerol transporters (19, 21, 25, 26). A clades, which show that silica biomineralization is widespread different member of this aquaporin family was recently identi- across terrestrial plant linages. Particularly high silica abundances fied that enables silica uptake in the horsetail Equisetum,an are observed in lycophytes and early-diverging ferns. -
Guidance for Identification and Naming of Substance Under REACH
Guidance for identification and naming of substances under 3 REACH and CLP Version 2.1 - May 2017 GUIDANCE Guidance for identification and naming of substances under REACH and CLP May 2017 Version 2.1 2 Guidance for identification and naming of substances under REACH and CLP Version 2.1 - May 2017 LEGAL NOTICE This document aims to assist users in complying with their obligations under the REACH and CLP regulations. However, users are reminded that the text of the REACH and CLP Regulations is the only authentic legal reference and that the information in this document does not constitute legal advice. Usage of the information remains under the sole responsibility of the user. The European Chemicals Agency does not accept any liability with regard to the use that may be made of the information contained in this document. Guidance for identification and naming of substances under REACH and CLP Reference: ECHA-16-B-37.1-EN Cat. Number: ED-07-18-147-EN-N ISBN: 978-92-9495-711-5 DOI: 10.2823/538683 Publ.date: May 2017 Language: EN © European Chemicals Agency, 2017 If you have any comments in relation to this document please send them (indicating the document reference, issue date, chapter and/or page of the document to which your comment refers) using the Guidance feedback form. The feedback form can be accessed via the EVHA Guidance website or directly via the following link: https://comments.echa.europa.eu/comments_cms/FeedbackGuidance.aspx European Chemicals Agency Mailing address: P.O. Box 400, FI-00121 Helsinki, Finland Visiting address: Annankatu 18, Helsinki, Finland Guidance for identification and naming of substances under 3 REACH and CLP Version 2.1 - May 2017 PREFACE This document describes how to name and identify a substance under REACH and CLP. -
Biomineralization and Global Biogeochemical Cycles Philippe Van Cappellen Faculty of Geosciences, Utrecht University P.O
1122 Biomineralization and Global Biogeochemical Cycles Philippe Van Cappellen Faculty of Geosciences, Utrecht University P.O. Box 80021 3508 TA Utrecht, The Netherlands INTRODUCTION Biological activity is a dominant force shaping the chemical structure and evolution of the earth surface environment. The presence of an oxygenated atmosphere- hydrosphere surrounding an otherwise highly reducing solid earth is the most striking consequence of the rise of life on earth. Biological evolution and the functioning of ecosystems, in turn, are to a large degree conditioned by geophysical and geological processes. Understanding the interactions between organisms and their abiotic environment, and the resulting coupled evolution of the biosphere and geosphere is a central theme of research in biogeology. Biogeochemists contribute to this understanding by studying the transformations and transport of chemical substrates and products of biological activity in the environment. Biogeochemical cycles provide a general framework in which geochemists organize their knowledge and interpret their data. The cycle of a given element or substance maps out the rates of transformation in, and transport fluxes between, adjoining environmental reservoirs. The temporal and spatial scales of interest dictate the selection of reservoirs and processes included in the cycle. Typically, the need for a detailed representation of biological process rates and ecosystem structure decreases as the spatial and temporal time scales considered increase. Much progress has been made in the development of global-scale models of biogeochemical cycles. Although these models are based on fairly simple representations of the biosphere and hydrosphere, they account for the large-scale changes in the composition, redox state and biological productivity of the earth surface environment that have occurred over geological time. -
Nutrient Cycles, Biodegradation, and Bioremediation
LECTURE PRESENTATIONS For BROCK BIOLOGY OF MICROORGANISMS, THIRTEENTH EDITION Michael T. Madigan, John M. Martinko, David A. Stahl, David P. Clark Chapter 24 Nutrient Cycles, Lectures by Biodegradation, and John Zamora Middle Tennessee State University Bioremediation © 2012 Pearson Education, Inc. I. Nutrient Cycles • 24.1 The Carbon Cycle • 24.2 Syntrophy and Methanogenesis • 24.3 The Nitrogen Cycle • 24.4 The Sulfur Cycle • 24.5 The Iron Cycle • 24.6 The Phosphorus, Calcium and Silica Cycles © 2012 Pearson Education, Inc. Marmara University – Enve3003 Env. Eng. Microbiology – Assist. Prof. Deniz AKGÜL 24.1 The Carbon Cycle • Carbon is cycled through all of Earth’s major carbon reservoirs (Figure 24.1) – Includes atmosphere, land, oceans, sediments, rocks and biomass © 2012 Pearson Education, Inc. Marmara University – Enve3003 Env. Eng. Microbiology – Assist. Prof. Deniz AKGÜL CO2 Human Figure 24.1 The carbon cycle activities Respiration The greatest reservoir of carbon on Earth is in rocks and sediments and most of this is in inorganic form as Land Animals and plants microorganisms carbonates Aquatic CO2 CO2 plants and Aquatic Human phyto- animals plankton Biological pump activities Fossil CO2 Humus Death and fuels mineralization Soil formation Respiration Earth’s crust Rock formation Land Animals and plants microorganisms Aquatic CO2 plants and Aquatic phyto- animals plankton Biological pump Fossil CO2 Humus Death and fuels mineralization Soil formation Earth’s crust Rock formation The carbon and oxygen cycles are closely connected, as oxygenic photosynthesis both removes CO2 and produces O2 and respiratory processes both produce CO2 and remove O2 © 2012 Pearson Education, Inc. Marmara University – Enve3003 Env. Eng. -
Study of the System Cao-Sio2-H2O at 30 C and of the Reaction of Water On
U.S. Department of Commerce Bureau of Standards RESEARCH PAPER RP687 Part of Bureau of Standards Journal of Research, vol. 12, June 1934 STUDY OF THE SYSTEM CaO-Si02-H2 AT 30 C AND OF THE REACTION OF WATER ON THE ANHYDROUS CALCIUM SILICATES By E. P. Flint and Lansing S. Wells abstract A graph has been prepared representing the solubility of silica at 30 C in solu- tions containing increasing concentrations of lime up to saturation, the solutions being in "equilibrium" with solid phases composed of hydrated combinations of lime and silica. An electrometric and analytical study of both supersaturated and unsaturated solutions of silica at definite concentrations of lime, when corre- lated with these equilibrium solubility relationships, indicates the existence of definite compounds in the system CaO-Si0 2-H 2 which may be the hydrated calcium salts of orthosilicic acid. Experimental values were obtained for the hydrolysis constants of these salts from which ionization constants for the four steps in the dissociation of orthosilicic acid were calculated. A study of the reaction of water upon the anhydrous calcium silicates (CaO Si02 , 3CaO- 2Si0 2 , 7-2CaO-Si0 ,3-2CaO Si0 , ) showed that the products formed depend 2 , 2 3CaOSi0 2 upon the equilibrium relationships of the system CaO-Si02-H 2 0. Of these compounds all but monocalcium silicate (CaO-Si02 ) form solutions which pre- cipitate hydrated calcium silicate on standing. Application of the same methods to a study of the reaction of water upon a portland cement indicated that hydrated calcium orthosilicate is formed during the hydration of portland cement. -
United States Patent (19) 11 4,169,930 Blount 45) Oct
United States Patent (19) 11 4,169,930 Blount 45) Oct. 2, 1979 (54) PROCESS FOR THE PRODUCTION OF 58 Field of Search ................. 260/448.2 N, 448.2 E; AMNO SILICATE COMPOUNDS AND 528/38 THER CONDENSATION PRODUCTS 76 Inventor: David H. Blount, 5450 Lea St., San 56) References Cited Diego, Calif. 92105 U.S. PATENT DOCUMENTS 21 Appl. No.: 786,617 4,011,253 3/1977 Blount ........................... 260/448.2 E 4,089,883 5/1978 Blount ....................... 260/448.2 E X (22) Filed: Apr. 8, 1977 Primary Examiner-Paul F. Shaver Related U.S. Application Data 57 ABSTRACT 60) Division of Ser. No. 652,338, Jan. 26, 1976, Pat. No. 4,033,935, which is a continuation-in-part of Ser. No. Silicic-amino compounds are formed by the chemical 559,313, Mar. 17, 1975, Pat. No. 3,979,362, which is a reaction of silicic acid with amino compounds in the continuation-in-part of Ser. No. 71,628, Sep. 11, 1970, presence of a suitable alkali at a suitably elevated tem abandoned. perature, and then by reacting the resultant compounds 51 Int. Cl’.............................................. C08G 77/04 with an aldehyde, a condensation product is formed. (52) U.S. C. .............................. 528/38; 260/448.2 N; 260/448.2 E 4 Claims, No Drawings 4,169,930 1. 2 PROCESS FOR THE PRODUCTION OF AMINO Reactions with other amino compounds are expected SILICATE COMPOUNDS AND THER to be similar to these, so that the mol ratios of the reac CONDENSATION PRODUCTS tants should be selected accordingly. Amino silicate compounds are theorized to react with CROSS-REFERENCE TO RELATED an aldehyde to form condensation products as follows: APPLICATIONS Urea silicate is theorized to react with formaldehyde This application is a division of U.S. -
A Bound Form of Silicon in Glycosaminoglycans And
Proc. Nat. Acad. Sci. USA Vol. 70, No. 5, pp. 1608-1612, May 1973 A Bound Form of Silicon in Glycosaminoglycans and Polyuronides (polysaccharide matrix/connective tissue) KLAUS SCHWARZ Laboratory of Experimental Metabolic Diseases, Veterans Administration Hospital, Long Beach, California 90801; and Department of Biological Chemistry, School of Medicine, University of California at Los Angeles, Calif. 90024 Communicated by P. D. Boyer, March 19, 1973 ABSTRACT Silicon was found to be a constituent of notably hyaluronic acid, chondroitin 4-sulfate, dermatan certain glycosaminoglycans and polyuronides, where it sulfate, and heparan sulfate, contain relatively large amounts occurs firmly bound to the polysaccharide matrix. 330-554 ppm of bound Si were detected in purified hyaluronic acid of the element, not as free silicate ions or silicic acid but as a from umbilical cord, chondroitin 4-sulfate, dermatan firmly bound component of the polysaccharide matrix. High sulfate, and heparan sulfate. These amounts correspond to amounts of bound Si were also detected in two polyuronides, 1 atom of Si per 50,000-85,000 molecular weight or 130-280 pectin and alginic acid. Stability tests and enzymatic studies repeating units. 57-191 ppm occur in chondroitin 6-sulfate, evidence for the assumption that the Si is linked heparin, and keratan sulfate-2 from cartilage, while provide hyaluronic acids from vitreous humor and keratan sulfate- covalently to the polysaccharides in question, possibly as an 1 from cornea were Si-free. Large amounts of bound Si are ether (or ester-like) derivative of silicic acid, i.e., a silanolate. also present in pectin (2580 ppm) and alginic acid (451 ppm). -
Water at Molecular Interfaces: Structure and Dynamics Near Biomolecules and Amorphous Silica
WATER AT MOLECULAR INTERFACES: STRUCTURE AND DYNAMICS NEAR BIOMOLECULES AND AMORPHOUS SILICA DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Ali A. Hassanali, M.S. Biophysics Graduate Program The Ohio State University 2010 Dissertation Committee: Professor Sherwin J. Singer, Adviser Professor Dongping Zhong Professor Terrence Conlisk Professor Justin Wu ABSTRACT Water, the fundamental constituent of life, has been found to have a critical role at both organic and inorganic surfaces. The properties of water near surfaces, is known to be different from water far away from the interface. This dissertation explores the degree to which inorganic materials such as amorphous silica (glass) and biomolecular surfaces change the properties of water. Of particular interest is the interplay between biological molecules - proteins and nucleic acids - and their aqueous environment, and how this determines biological function. The mobility of water near protein surfaces has been of considerable recent in- terest. There have been many reports in the literature postulating that interfacial water is incapable of undergoing rapid rotational motions due to strong electrostatic forces from the protein surface. This has led to confusing and conflicting interpre- tations on the molecular origin of the slow features observed in certain experiments that probe protein surfaces. Our theoretical studies resolve the conflicts and show that the slow dynamics observed, originates from the protein and water jostling in a concerted fashion. Our studies support a change in the paradigm for the function of proteins to include both the protein and the surrounding water as active participants in biological function. -
Synthesis and Characterization of Silicate Ester Prodrugs and Poly(Ethylene Glycol)
Synthesis and Characterization of Silicate Ester Prodrugs and Poly(ethylene glycol)-b-poly(lactic-co-glycolic acid) Block Copolymers for Formulation into Prodrug-Loaded Nanoparticles A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Adam Richard Wohl IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy Thomas R. Hoye, Advisor September 2012 © Adam Richard Wohl September 2012 Acknowledgements I have been blessed to have the support of my family, friends, and colleagues. Without your help and encouragement, my graduate career would not have been possible. First of all, I would like to thank my advisor Prof. Tom Hoye. Over the past five years, he has been a consistent and patient mentor that leads first and foremost by setting a world-class example. He has taught me so much about analyzing problems, having fun while working hard, and always paying attention to the details. He has constantly taught me during our experimental discussions, results analysis, and late night (or, as I believe Tom would say, “mid-evening”) grant/manuscript writing sessions. I have learned not only many, many chemical concepts and scientific strategies, but also other valuable skills – how to clearly present ideas and make a compelling presentation to the right audience. Thank you, Tom, for all of the time that you have invested in both my scientific career and life – you have my utmost appreciation and respect. I would also like to thank Prof. Chris Macosko for all of his time, help, and expertise that he has provided to this collaborative project. -
Unveiling the Role of Rhizaria in the Silicon Cycle Natalia Llopis Monferrer
Unveiling the role of Rhizaria in the silicon cycle Natalia Llopis Monferrer To cite this version: Natalia Llopis Monferrer. Unveiling the role of Rhizaria in the silicon cycle. Other. Université de Bretagne occidentale - Brest, 2020. English. NNT : 2020BRES0041. tel-03259625 HAL Id: tel-03259625 https://tel.archives-ouvertes.fr/tel-03259625 Submitted on 14 Jun 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THESE DE DOCTORAT DE L'UNIVERSITE DE BRETAGNE OCCIDENTALE ECOLE DOCTORALE N° 598 Sciences de la Mer et du littoral Spécialité : Chimie Marine Par Natalia LLOPIS MONFERRER Unveiling the role of Rhizaria in the silicon cycle (Rôle des Rhizaria dans le cycle du silicium) Thèse présentée et soutenue à PLouzané, le 18 septembre 2020 Unité de recherche : Laboratoire de Sciences de l’Environnement Marin Rapporteurs avant soutenance : Diana VARELA Professor, Université de Victoria, Canada Giuseppe CORTESE Senior Scientist, GNS Science, Nouvelle Zélande Composition du Jury : Président : Géraldine SARTHOU Directrice de recherche, CNRS, LEMAR, Brest, France Examinateurs : Diana VARELA Professor, Université de Victoria, Canada Giuseppe CORTESE Senior Scientist, GNS Science, Nouvelle Zélande Colleen DURKIN Research Faculty, Moss Landing Marine Laboratories, Etats Unis Tristan BIARD Maître de Conférences, Université du Littoral Côte d’Opale, France Dir. -
Silica Production and the Contribution of Diatoms to New and Primary Production in the Central North Pacific
MARINE ECOLOGY PROGRESS SERIES Vol. 167: 89-104.1998 Published June 18 Mar Ecol Prog Ser Silica production and the contribution of diatoms to new and primary production in the central North Pacific Mark A. ~rzezinskil*:Tracy A. Villarea12,Fredric ~ipschultz~ 'Marine Science Institute and the Department of Ecology Evolution and Marine Biology, University of California, Santa Barbara, California 93106, USA 'The University of Texas at Austin. Marine Science Institute, 750 Channel View Drive, Port Aransas, Texas 78373-5015, USA 3Bermuda Biological Station for Research. Ferry Reach GE 01, Bermuda ABSTRACT: The silica cycle in the upper 200 m of the central North Pacific was examined to further as- sess the role of oligotrophic mid-ocean gyres in the global marine silica cycle and to evaluate the role of diatoms in the regional carbon and nitrogen cycles. Siliceous biomass in the upper 200 m was very low (generally c50 nmol S1 1.' of biogenic silica) with, higher concentrations (100 to 280 nmol Si 1.') ob- served occasionally in the deep chlorophyll maximum and in the nitracline Doubling times for biogenic silica were generally between 2 and 5 d, suggesting fairly rapid diatom growth. Ki~ieiicexperiments showed widespread limitation of silica production rates by ambient silicic acid concentrations (0.9 to 3.0 pM). Inputs of iron inferred from high concentrations of lithogenic silica (up to 300 nmol Si 1-l) in surface waters did not stimulate silica production. lntegrated silica production rates averaged 1.24 mm01 Si m-' d-' (range 0.47 to 2.9 mm01 Si m-' d-') This average is 2 to 3 times higher than those reported for other oligotrophic mid-ocean gyres, significantly increasing estimates of the fraction of global silica production occurring in these systems.