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Determination of total and inorganic mercury in whole blood by cold vapor inductively coupled plasma mass spectrometry (CV ICP-MS) with alkaline sample preparation

RODRIGUES, Jairo L.; TORRES, Daiane P.; SOUZA, Vanessa C. de Oliveira; BATISTA, Bruno L.; SOUZA, Samuel S. de; CURTIUS, Adilson J.; BARBOSA JR., Fernando
Fonte: ROYAL SOC CHEMISTRY Publicador: ROYAL SOC CHEMISTRY
Tipo: Artigo de Revista Científica
ENG
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A simple method with a fast sample preparation procedure for total and inorganic mercury determinations in blood samples is proposed based on flow injection cold vapor inductively coupled plasma mass spectrometry (FI-CVICP-MS). Aliquots of whole blood (500 mL) are diluted 1 + 1 v/v with 10.0% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 3 h at room temperature and then further diluted 1 + 4 v/v with 2.0% v/v HCl. The inorganic Hg was released by online addition of L-cysteine and then reduced to elemental Hg by SnCl(2). On the other hand, total mercury was determined by on-line addition of KMnO(4) and then reduced to elemental Hg by NaBH(4). Samples were calibrated against matrix-matching. The method detection limit was found to be 0.80 mu g L(-1) and 0.08 mu g L(-1) for inorganic and total mercury, respectively. Sample throughput is 20 samples h(-1). The method accuracy is traceable to Standard Reference Material (SRM) 966 Toxic Metals in Bovine Blood from the National Institute of Standards and Technology (NIST). For additional validation purposes, human whole blood samples were analyzed by the proposed method and by an established CV AAS method, with no statistical difference between the two techniques at 95% confidence level on applying the t-test.

Gerenciamento dos resíduos da disciplina Química Inorgânica II do Curso de Química da Universidade Federal do Rio Grande do Sul; Management of residues of an undergraduate Inorganic Chemistry course at the Federal University of Rio Grande do Sul

Gerbase, Annelise Engel; Gregorio, Jose Ribeiro; Calvete, Tatiana
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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Beginning students in chemistry usually do not realize that wastes generated in their experimental classes constitute an environmental problem and that residues must be treated or disposed of in a suitable way. In this manuscript we describe the work that we have been doing in the inorganic chemistry course of the Federal University of Rio Grande do Sul with the objective of creating a critical consciousness in the students about the chemical wastes they generate. With this policy, students are required to take into account the nature of the residues they generate, how they can treat or segregate them, and how they can keep them in a suitable way for final destination, instead of simply throwing them away.

Gerenciamento dos resíduos da disciplina química inorgânica II do curso de química da Universidade Federal do Rio Grande do Sul

Gerbase,Annelise Engel; Gregório,José Ribeiro; Calvete,Tatiana
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2006 PT
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Beginning students in chemistry usually do not realize that wastes generated in their experimental classes constitute an environmental problem and that residues must be treated or disposed of in a suitable way. In this manuscript we describe the work that we have been doing in the inorganic chemistry course of the Federal University of Rio Grande do Sul with the objective of creating a critical consciousness in the students about the chemical wastes they generate. With this policy, students are required to take into account the nature of the residues they generate, how they can treat or segregate them, and how they can keep them in a suitable way for final destination, instead of simply throwing them away.

Laboratory projects using inquiry-based learning: an application to a practical inorganic course

Carriazo,José G.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
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This paper reports how laboratory projects (LP) coupled to inquiry-based learning (IBL) were implemented in a practical inorganic chemistry course. Several coordination compounds have been successfully synthesised by students according to the proposed topics by the LP-IBL junction, and the chemistry of a number of metals has been studied. Qualitative data were collected from written reports, oral presentations, lab-notebook reviews and personal discussions with the students through an experimental course with undergraduate second-year students at the Universidad Nacional de Colombia during the last 5 years. Positive skills production was observed by combining LP and IBL. Conceptual, practical, interpretational, constructional (questions, explanations, hypotheses), communicational, environmental and application abilities were revealed by the students throughout the experimental course.

5.068 Physical Methods in Inorganic Chemistry, Spring 2005; Physical Methods in Inorganic Chemistry

Mueller, Peter
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
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Introduction to the study of physical methods to probe the electronic and geometric structure of inorganic compounds. Included are electronic photoelectron spectroscopy; vibrational and rotational spectroscopy; magnetic measurements (including electron and nuclear spin resonance); Mossbauer spectroscopy; mass spectrometry; electrochemical measurements and crystallographic chemical analysis (including hands-on use of departmental facilities). From the course home page: Course Description This course covers the following topics: X-ray diffraction: symmetry, space groups, geometry of diffraction, structure factors, phase problem, direct methods, Patterson methods, electron density maps, structure refinement, how to grow good crystals, powder methods, limits of X-ray diffraction methods, and structure data bases.

The exploratory synthesis of low-dimensional inorganic solids: Structure and property correlation studies of novel mixed-metal niobium oxo compounds

Serra, Deborah L.
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
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47.342637%
The search for a new class of compounds with quasi-low-dimensional frameworks has become important for the development of new transition metal oxides that are of magnetic and electronic importance. The exploratory synthesis of low-dimensional inorganic solids, in particular reduced niobium oxophosphates and oxosilicates containing extended, but confined, M-O-M and M-M bond interactions, has been investigated. These bonding types are common structural features observed in metallic oxides that possess unusual phenomena associated with charge density waves, superconductivity, and magnetic ordering. Ultimately, these new compounds should lead to structural models for experimental and theoretical studies of the behavior of delocalized electrons in a confined lattice. A number of significant solid state compounds with interesting structures and physical properties have been prepared through our exploratory synthesis. Four tetragonal tungsten bronze-related (TTB) mixed-metal oxides have been made; namely BaNb$sb2 m Osb{6- m x},$ orthorhombic NbPO$sb5,$ and ANb$sb3 m Psb3Osb15$ (A = Cs, and Ba). The niobium oxophosphate compounds, BaNb$sb7 m Psb6Osb{33}$ and CaNb$sb2$P$ msb2Osb{11},$ with mixed-frameworks and fused NbO$sb6$ octahedra have also been prepared and studied. Finally...

Inorganic-organic materials incorporating alumoxane nanoparticles

Vogelson, Cullen Taylor
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
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Chemically functionalized alumina nanoparticles (carboxylate-alumoxanes) are used as the inorganic component of a new class of inorganic-organic material. Lysine- or para-hydroxybenzoic acid-derivatized alumoxanes are prepared from the reaction of boehmite, [Al(O)(OH)]n, with the appropriate carboxylic acid. The peripheral hydroxides and amines of these alumoxanes react directly with DER 332 epoxide to form a hybrid material, or in the presence of a resin and hardener system, to form a composite material. Solid state NMR spectroscopy demonstrates that the alumoxanes are chemically bound to the resin matrix. The properties and cure times of the alumoxane materials are distinct from both the pure resins and from a physical blend of the resins with traditional fillers. A significant increase in thermal stability and tensile strength is observed for the resin systems. In order to produce molecular coupling layers, epoxides cross-linked with self-assembled monolayers (SAMs) grown on the native oxide of aluminum thin films on silicon substrates have been investigated. Specifically, SAMs have been formed by the attachment of different carboxylic acids. In order to investigate the cross-linking reaction between carboxylate monolayers and an epoxide...

Studies in gas phase ion chemistry : a thesis presented for the degree of Doctor of Science in the Faculty of Science of the University of Adelaide / by Richard Alfred John O'Hair.

O'Hair, Richard Alfred John
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado Formato: 32963 bytes; application/pdf
Publicado em //2004 EN
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Thesis (D.Sc.)--University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2005; "December 2004"; Includes bibliographical references.; 2 v. (various pagings) :; Title page, contents and abstract only. The complete thesis in print form is available from the University Library.

Análisis de la evolución de las concepciones de la ndc a través de secuencias didácticas centradas en aspectos sociológicos de la nomenclatura de compuestos químicos inorgánicos

Guzmán Prada, Yasunari
Fonte: Ibagué : Universidad del Tolima, 2015; Facultad de Ciencias de la Educación, Programa de Maestría en Educación Publicador: Ibagué : Universidad del Tolima, 2015; Facultad de Ciencias de la Educación, Programa de Maestría en Educación
Tipo: Trabajo de grado - Maestría; Text; info:eu-repo/semantics/masterThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
SPA
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146 Páginas; Recurso Electrónico; La presente investigación tiene como objeto de estudio determinar la evolución de las concepciones sobre Naturaleza de la Ciencia “NdC” que tienen los estudiantes de educación media colombiana a través de secuencias didácticas centrada en aspectos sociológicos de la Nomenclatura de Compuestos Químicos Inorgánicos “NCQI”. El problema de investigación se sustenta desde la perspectiva teórica de la naturaleza de ciencia y las concepciones metadisciplinares que los estudiantes tienen sobre ésta. Se plantea un estudio de carácter educativo, bajo un enfoque cualitativo-hermenéutico. En el análisis de contenido se identificó el sentido explícito de las ideas de los estudiantes acerca de la Nomenclatura de Compuestos Químicos Inorgánicos “NCQI” y la incidencia de estos compuestos en el medio ambiente. El proceso de investigación estuvo regido por un sistema categorial que orientó el proceso, el cual se encuentra en el marco de los consensos de naturaleza de ciencia (Aduriz, 2001). En los resultados y las conclusiones se presentan las concepciones que tienen los estudiantes sobre NdC desde el componente sociológico de la NCQI a partir de la incidencia de la aplicación de las secuencias didácticas en la evolución conceptual.; ABSTRACT. This research study aims to determine the evolution of the conceptions of Nature of Science "NdC" with the Colombian high school students through didactic sequences focused on sociological aspects of the Nomenclature of Inorganic Chemistry "NCQI". The research problem is based from the theoretical perspective of the nature of science and metadisciplinares conceptions that students have on it. A study of educational...

The synthesis of inorganic semiconductor nanocrystalline materials for the purpose of creating hybrid organic/inorganic light-emitting devices; Synthesis of inorganic semiconductor NC materials for the purpose of creating hybrid organic/inorganic LEDs

Steckel, Jonathan S. (Jonathan Stephen)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 213 p.
ENG
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Colloidal semiconductor nanocrystals (NCs) or quantum dots (QDs) can be synthesized to efficiently emit light from the ultraviolet, across the entire visible spectrum, and into the near infrared. This is now possible due to the continual development of new core and core-shell NC structures to meet specific color needs in areas as diverse as optoelectronic devices to biological imaging. Core-shell semiconductor NCs are unique light emitters. They are more stable overtime to photobleaching compared to organic dyes. Their emission is efficient and their spectral full width at half maximum remains highly narrow as their size is synthetically changed to provide desired peak wavelengths of emission to within plus or minus a couple of nanometers. They can be purified and manipulated in solution and their chemical interaction with the environment is the same for all sizes and can be modified using chemical techniques. These unique properties make semiconductor NCs ideal for use in light emitting devices (QD-LEDs). This work shows how electroluminescence can be extended into the near infrared region of the spectrum by employing infrared emitting NCs as well as into the blue region of the spectrum by designing and synthesizing NCs specifically for this application.; (cont.) Once efficient and color saturated electroluminescence at the visible spectrum's extremes had been realized it was a natural extension to begin exploring the potential of QD-LED devices to satisfy the technological requirements of flat panel displays and imaging applications. This led to the synthesis of a new green-emitting core-shell NC material to meet the specific color needs for flat panel display applications. At the same time we developed a new QD-LED device fabrication method to allow the patterning of the NC monolayer in our devices. Micro-contact printing the NC monolayer instead of using phase separation provided efficient and highly color saturated QD--LEDs in the red...

Polyoxometalates: from inorganic chemistry to materials science

Gómez-Romero, P.; Casañ Pastor, Nieves
Fonte: Frontiers in Bioscience Publications Publicador: Frontiers in Bioscience Publications
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
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Full-text available Open Access at: http://www.cienciateca.com/POMs%20Frontiers%20in%20Bioscience2004.pdf; Polyoxometalates have been traditionally the subject of study of molecular inorganic chemistry. Yet, these polynuclear molecules, reminiscent of oxide clusters, present a wide range of structures and with them ideal frameworks for the deployment of a plethora of useful magnetic, electroionic, catalytic, bioactive and photochemical properties. With this in mind, a new trend towards the application of these remarkable species in materials science is beginning to develop. In this review we analyze this trend and discuss two main lines of thought for the application of polyoxometalates as materials. On the one hand, there is their use as clusters with inherently useful properties on themselves, a line which has produced fundamental studies of their magnetic, electronic or photoelectrochemical properties and has shown these clusters as models for quantum-sized oxides. On the other hand, the encapsulation or integration of polyoxometalates into organic, polymeric or inorganic matrices or substrates opens a whole new field within the area of hybrid materials for harnessing the multifunctional properties of these versatile species in a wide variety of applications...

Rapid and quantitative release, separation and determination of inorganic arsenic [As(III) plus As(V)] in seafood products by microwave-assisted distillation and hydride generation atomic absorption spectrometry

Muñoz, Ociel; Vélez, Dinoraz; Cervera, María Luisa; Montoro, Rosa
Fonte: Royal Society of Chemistry (Great Britain) Publicador: Royal Society of Chemistry (Great Britain)
Tipo: Artículo Formato: 137517 bytes; 2459 bytes; application/pdf; text/plain
ENG
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A precise, simple and rapid method is described for the determination of inorganic arsenic [As(iii)+As(v)] in seafood products. The inorganic species were isolated from the matrix by microwave-assisted distillation and determined by hydride generation atomic absorption spectrometry (HGAAS). The microwave and chemical parameters were optimized in order to obtain quantitative inorganic arsenic recoveries. The analytical features of the method are as follows: detection limit 10 ng g(-1) (dry mass) or 2 ng g(-1) (fresh mass); precision (RSD) 4%; recoveries 106 +/- 3% for As(iii) and 113 +/- 4% for As(v). Under the optimized conditions, arsenobetaine, arsenocholine and tetramethylarsonium ion added to samples of seafood were not distilled; however, minor species were distilled and were detected in various percentages: 109% monomethylarsonic acid; 11% dimethylarsinic acid; 0.2% trimethylarsine oxide. The concentrations expressed as arsenic contributed by these species would imply a mean overestimate of inorganic arsenic of about 24 ng g(-1) dry mass (dm). The concentrations of inorganic arsenic found in natural seafood samples ranged between 0.053 and 1.145 mu g g(-1) (dm) (mean moisture content 78%). The procedure was compared with an alternative methodology in which acid digestion-solvent extraction-HGAAS was used for the determination of inorganic arsenic. A Student's t-test for paired samples of the data obtained by the two methodologies showed no significant differences (P -value 0.66).; Comisio´n Interministerial de Cienc´ıa y Tecnolog´ıa (CICyT)...

Optimization of the solubilization, extraction and determination of inorganic arsenic [As(III)+As(V)] in seafood products by acid digestion, solvent extraction and hydride generation atomic absorption spectrometry

Muñoz, Ociel; Vélez, Dinoraz; Montoro, Rosa
Fonte: Royal Society of Chemistry (Great Britain) Publicador: Royal Society of Chemistry (Great Britain)
Tipo: Artículo Formato: 165904 bytes; 2459 bytes; application/pdf; text/plain
ENG
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A method for the selective quantitative determination of inorganic arsenic [As(III) + As(v)] in seafood was developed. In order to do so, various procedures for the solubilization and extraction of inorganic arsenic quoted in the literature were tested. None provided satisfactory recoveries for As(III) and As(v) in real samples. Consequently, a methodology was developed which included solubilization with HCl and subsequent extraction with chloroform. The arsenic was solubilized in 9 mol 1(-1) hydrochloric acid. After reduction by hydrobromic acid and hydrazine sulfate, the inorganic arsenic was extracted into chloroform, back-extracted into 1 mol 1(-1) HCl, dry-ashed, and quantified by hydride generation-atomic absorption spectrometry (HG-AAS). The analytical features of the method are as follows: detection limit, 3.07 ng g(-1) As (fresh mass); precision (RSD), 4.0%; recovery, As(III) 99%, As(v) 96%. In the optimized conditions, other arsenic species-dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC) and tetramethylarsonium-ion (TMA(+))-were not co-extracted. However, different percentages of minor species were extracted with chloroform: monomethylarsonic acid (MMA) 100%, and trimethylarsine oxide (TMAO) 3-10%. Real samples and reference materials of seafood (DORM-1...

Recursos per treballar a l’aula la formulació i nomenclatura de química inorgànica

Hernández Santadaría, José Ángel
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2015 CAT
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L’article presenta diversos recursos i activitats elaborats per l’autor que permeten treballar la formulació i nomenclatura de química inorgànica a les classes de química d’educació secundària i de batxillerat, seguint les darreres recomanacions de la IUPAC de l’any 2005.; This article sets forth several resources and activities designed by the author which allow the inclusion of formula writing and nomenclature of inorganic chemistry in the chemistry lessons of compulsory secondary education and Baccalaureate, following the latest IUPAC recommendations in 2005.

Caveats for poly(methimazolyl)borate chemistry: the novel inorganic heterocycles [H 2 C(mt) 2 BR 2 ]Cl (mt = methimazolyl; BR 2 = BH 2 , BH(mt), 9�BBN)

Crossley, Ian R; Hill, Anthony; Humphrey, Elizabeth; Smith, Matthew; Tshabang, Never; Willis, Anthony
Fonte: Royal Society of Chemistry Publicador: Royal Society of Chemistry
Tipo: Artigo de Revista Científica
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Whilst frequently used for reactions of poly(methimazolyl)borates, dichloromethane is not an innocent solvent, but rather slowly forms heterocyclic salts [H2C(mt)2BR2]Cl, three examples of which (BR2 = BH2, BH(mt), 9-borabicyclononyl) have been structurally characterised to confirm the unprecedented B(NCS)2C connectivity.

Coordination Chemistry: An Audacious Dream of Alfred Werner; Química de Coordenação: Um Sonho Audacioso de Alfred Werner

Leandro Marcos Santos; Universidade Federal de Alfenas; Luís Eduardo Sarto; Universidade Federal de Alfenas; Gabriela Francini Bozza; Universidade Federal de Alfenas; Eduardo T. de Almeida; Universidade Federal de Alfenas
Fonte: Revista Virtual de Química Publicador: Revista Virtual de Química
Tipo: ; Formato: binary/octet-stream
Publicado em 01/11/2014 PT
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2013 was the centennial celebration of the Nobel Prize awarded to Alfred Werner in recognition of his important scientific contributions to Inorganic Chemistry. Through his ideological audacity, acumen in chemical experimentation and wide theoretical knowledge, Werner was able to found the conceptual basis for understanding and explaining one of the most fascinating areas of Inorganic Chemistry: Coordination Chemistry. This paper presents the scientific findings and also the available tools at the time Werner developed his theory for which he was awarded the Nobel Prize in Chemistry in 1913. DOI: 10.5935/1984-6835.20140083; Em 2013 comemoraram-se cem anos que Alfred Werner foi laureado com o Prêmio Nobel, em reconhecimento por suas importantes contribuições científicas à Química Inorgânica. Somando sua audácia ideológica, sua perspicácia na experimentação química e seu vasto conhecimento teórico, Werner foi capaz de fundar as bases conceituais para a compreensão e explicação de uma das mais fascinantes áreas da Química Inorgânica: a Química de Coordenação. Este artigo apresenta as constatações científicas e também as ferramentas disponíveis na época em que Werner desenvolveu sua teoria que lhe rendeu o Prêmio Nobel de Química em 1913. DOI: 10.5935/1984-6835.20140083

James Moir as Inorganic Chemist

Loyson,Peter
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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James Moir was a pioneering chemist in the early 1900s who played a leading role in various chemical societies in South Africa. Although he was mainly an organic chemist, he also made contributions in the field of inorganic chemistry. His forays in this field deal with gold extraction using the new solvent thiourea, removal of cyanide using ferrous sulphate, and investigations into the 'purple of Cassius'. He was also a theoretical chemist who played a role in the development of atomic theory and made suggestions to help unravel the nature of the atom, the composition of the nucleus and chemical combination.

The Contributions of James Moir to Physical Chemistry

Loyson,P.
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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James Moir was a pioneering chemist in the early 1900s who played a leading role in various chemical societies in South Africa. Although he was mainly an organic chemist, he was a very good all-round chemist, whose analytical and organic activities have already been covered in this j ournal. This article examines his research in physical chemistry, covering the spectral analysis of the ruby and emerald gemstones, a detailed analysis of part of the Fraunhofer lines of the solar spectrum, and an examination of the spectra of cobalt compounds, the permanganate ion, and uranium compounds. Finally, as part of his inorganic and analytical investigations, he also delved into the physical chemistry aspects of solution chemistry, particularly the hydrolysis of the cyanide ion.

Inorganic-Organic Hybrids Incorporating a Chiral Cyclic Ammonium Cation

Lemmerer,Andreas; Billing,David G.
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
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In this paper we report the synthesis and the crystal structure of eight inorganic-organic hybrids containing various lead halides as the inorganic motif and a chiral, primary ammonium cation as the organic constituent. The organic cation investigated is (C6H11C*H(CH3)NH3)+ and both the (R) and (S) as well as the racemic (RS) forms were used. Within the structures obtained, three different inorganic motifs are displayed by the lead halide octahedra: 1-D polymeric face-sharing chains of formula ((R)-[C6H5CH(CH3)NH3)PbBr3](4) and [((S)-C6H5CH(CH3)NH3)PbBr3](5); 1-D polymeric corner-sharing ribbons based on the terminated-K2NiF4 type structure of formula ((R)-[C6H5CH(CH3)NH3)8Pb8I14](1) and [((S)-C6H5CH(CH3)NH3)8Pb8I14] (2); and 2-D corner-sharing layers based on the K2NiF4 perovskite structure type of formula [((RS)-C6H5CH(CH3)NH3)2PbBr4] (3), [((RS)C5H5CH(CH3)NH3)2PbCl4] (6), (R)-[C6H5CH(CH3)NH3)2PbCl4] (7) and [((S)-C6H5CH(CH3)NH3)2PbCl4] (8).

Characterisation of the inorganic chemistry of surface waters in South Africa

Huizenga,Jan Marten
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2011 EN
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The main purpose of this study was to determine a simple inorganic chemistry index that can be used for all surface waters in South Africa, in order to characterise the inorganic chemistry of surface waters. Water quality data collected up until 1999 from all sample monitoring stations (2 068 monitoring stations, 364 659 samples) in South Africa were transformed into an Excel dataset and subsequently quality screened using the stoichiometric charge balance, after which 196 570 (41%) of the water analyses could be used. Using an inorganic chemistry index (ICI) a more detailed analysis can be performed. The ICI shows that the surface water chemistry in South Africa is dominated by chemical weathering, chloride salinisation and sulphate contamination. Based on the importance of these factors, primary catchment areas in South Africa can be subdivided into 3 groups, each with their own characteristic water chemistry. The results of this study allowed the development of a ternary diagram in which the 3 factors are represented. This diagram can be used to investigate the variation of the inorganic water chemistry of South African surface waters in time and space.