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Magnetic Mineralogical Characteristics of Hamersley Iron Ores in Western Australia  [PDF]
William W. Guo
Journal of Applied Mathematics and Physics (JAMP) , 2015, DOI: 10.4236/jamp.2015.32023

This paper presents the research outcomes of a magnetic mineralogical study on Hamersley iron ores. Thermal magnetic analysis shows that typical high-grade martite-microplaty hematite or M- (mpl H) and martite-microplaty hematite-goethite or M-(mpl H)-g ores contain a small amount of original magnetite. A small amount of magnetite/maghemite and pyrite/pyrrhotite/siderite may exist in typical martite-goethite (M-G) and martite-ochreous goethite (M-oG) ores. In “the hardcap zone”, M-(H)-g ores contain a small amount of magnetite and maghemite. Compared with XRD, thermal magnetic analysis is not only more sensitive in identifying trace of magnetite contained in high-grade hematite ores, but also more diagnostic in identifying other unstable magnetic minerals like maghemite and pyrite/pyrrhotite/siderite co-existed in the ores.

Effects of particle characteristics on the granulation ability of iron ores during the sintering process  [PDF]
Sheng-li Wu,Juan Zhu,Ji-cheng Bei,Guo-liang Zhang,Xiao-bo Zhai
- , 2015, DOI: https://doi.org/10.1007/s12613-015-1149-0
Abstract: The granulation behavior of iron ores is essential for subsequent parameter optimization and efficient granulation, especially under changing material conditions. In this study, the effects of surface properties and particle size were analyzed using a laboratory granulation method; an estimation of the granulation of sintering blends was subsequently conducted for the base ores. Circularity and porosity were observed to negatively affect the granulation of iron ores, whereas wettability positively affected the granulation and was the most influential factor, indicating that wetting of iron ores is desirable during granulation. When iron ores with complex size distributions were granulated, the equivalent surface area was the main influencing factor for coarse particles larger than 1 mm and the ratio of adhering fines to intermediates was the main factor for fine particles smaller than 1 mm. By combining the granulation of coarse and fine particles with their proportioning, we proposed a calculation method for estimating the granulation ability of sintering blends. Good verification was demonstrated with the designed schemes. The results suggest that the developed method is effective for predicting the granulation of iron ore mixtures.
Geological Characteristics of Ores from the Jianchaling Nickel Sulfide Deposit

WANG Rui-ting,HE Ying,LIU Min-wu,QI Liang,WANG Dong-sheng,

地球学报 , 2002,
Abstract: Based on the study of the geological background of the Jianchaling nickel sulfide deposit and the geological-geochemical characteristics of its ores, it is concluded that the formation of the nickel sulfide deposit is closely related to Jianchaling magnesium-enriched ultrabasic intrusion. Its ore-forming substance was derived from the depth, and its complex ore-forming process includes on-the-spot melting segregation that took place during the ascending and the emplacement of the parent magma derived from partial melting of the upper mantle through the upper mantle lithosphere, the autometamorphism after the formation of the intrusion, and the hydrothermal fluid superposed reformation resulting from the intrusion of intermediate and acid magma. The metasomatism and reformation process of late intermediate and acid magma is the main factor responsible for the formation of some rich nickel orebodies. The nickel deposit has a low content of PGE and copper, and should hence belong to the magmatic liquation-hydrothermal reformation type ore deposit.
On the Evolving Types, Characteristics and Research Value of Ancient Scientific and Technological Files in China  [cached]
Yan-ming WANG
Cross-Cultural Communication , 2006, DOI: 10.3968/558
Abstract: On the analysis of the history and types of ancient scientific and technological files, the author summarized its characteristics by comparison with modern scientific and technological files. Then he discussed its research values to ancient civilization, ancient scientific and technological history, policy and status of China. Keywords: Ancient,scientific and technological files,science and technology,scientific and technological documents,type,characteristics Résumé Sur l’analyse de l’histoire et des types d’anciens archives scientifiques et technologiques, l’auteur a fait un résumé ses caractéristiques par une comparaison avec les archives modernes scientifiques et technologiques. Ensuite, il a fait une discussion sur sa valeur de recherche sur l’ancienne civilisaiton, l’ancienne histoire scientifique et technologique, la politique et les statuts de la Chine. Mots-clés: ancien, les archives scientifiques et technologiques, science et technologie, les documents scientifiques et technologiques, type, caractéristiques 摘 要 本文基於古代科技檔案演進的歷史脈絡與形成類型,通過與現代科技檔案的比較研究,總結歸納出古代科技檔案的若干特點,進而分析古代科技檔案對於中國古代文明、中國古代科學技術史和古代科技政策及地位的研究價值。 關鍵詞:古代;科技檔案;科學技術;科技文獻;類型;特點
Adriana Gomes Gouvea,Claudia Márcia Gomes,Luiz Marcos Matos,Talita Assun??o Souza
Revista Ciência da Madeira , 2012,
Abstract: The aim of this study was to analyze the technological characteristics for pulp production from three eucalyptus clones planted in two different sites derived from experiments considered clonal test from a Brazilian pulp industry. It was determined the wood basic density, the fibers morphologies and the chemical composition of clones(extractives content, lignin and carbohydrates). Kraft pulping was made, using alkali different loads in order to obtain pulps with kappa number 18± 1. The quality of site did not influence on fiber length, the surface area of vessels for all clones, in additional to the syringyl / guaiacyl for clone C. The quality of site influenced on the wood density, wall thickness, extractives content, lignin and syringyl / guaiacyl ratio (except for clone C) and carbohydrates. The cloneB showed the better performance on pulp production and an intermediate effect of site at technological characteristics, when comparing with Clones A and C. The Clone C showed the least effect of site on performance of pulp production and it was the only clone that showedno site effect in relation to syringyl/guaiacyl, indicating that this variable is an important parameter for pulp production regarding on performance and alkali loads.
Dekovi?, Z.,Ester, Z.,Dobrilovi?, M.
Rudarsko-Geolo?ko-Naftni Zbornik , 2005,
Abstract: The paper describes organisational-technological characteristics of blasting works during the excavation of the Gri Tunnel. The significance of blasting works during the excavation of the tunnel is shown through adjustment of blasting parameters taking into consideration the dynamics of the works, cost-effectiveness and influence of geological circumstances. Successfulness of blasting directly influences the subsequent tunnel excavation cycle both in terms of duration as well as eventually in terms of influence on the entire tunnel investment. Comparison of changes of basic blasting parameters during tunnel excavation ensured optimal excavation progress with minimal price per meter of tunnel progress.
Technological characteristics of rabbit meat with raised n-3 PUFA  [cached]
M. Bianchi,M. Betti,M. Petracci,C. Cavani
Italian Journal of Animal Science , 2011, DOI: 10.4081/ijas.2003.s1.444
Abstract: The dietary use of linseed in animal feeding has been proposed by many authors as a vegetable way (in alternative to fish oil or fish meal) to raise meat PUFA and mainly α- linolenic acid (C18:3 n-3) (Bernardini et al., 1999; Mattews et al., 2000; Riley et al., 2000; Rey et al., 2001). However, increasing amounts of PUFA could impair the technological characteristics of the meat for further processing (Enser, 1999). Main problems are concerned with lipid stability and meat colour changes over time which are related with both the out coming of rancid flavour and detrimental effects on the appearance of packaged further processed meat products...
Some Surface Characteristics of Six Hematite Ores from the Middleback Range Area, South Australia
International Journal of Mining Engineering and Mineral Processing , 2012, DOI: 10.5923/j.mining.20120102.09
Abstract: Surface chemical techniques were used in an attempt to characterise eight samples of hematite. The hematites studied were six samples from the Middleback Ranges (Iron Knob (2 samples), Iron Monarch, Iron Prince, Iron Princess and Iron Baron) and two high purity, synthetic sa mples. The isoelectric points of the hematite samples showed a wide variation in value (from <2 to 8) whereas the zero points of charge were in the range 5.5 to 7.5. Using a simple mathematical calculation it was possible to estimate the surface charge characteristics of these hematite samples which gave a much better picture of the true surface properties of these samples in an aqueous environment. It was hoped that this study would contribute to a better understanding of the interaction between different hematite samples and water, a mechanism that is important in many industrial applications e.g. slurry pumping, agglomeration and granulation.
Petrographic Characteristics of Manganese Bearing Rocks of Banswara Manganese Ores Belt, District Banswara, Rajasthan (India)  [PDF]
Mohd Shaif, F. N. Siddiquie, Subir Mukhopadhyay
Open Journal of Geology (OJG) , 2017, DOI: 10.4236/ojg.2017.77070
In this paper, we described the petrographical characters of the Mn-bearing rock types outcropping in the Kalakhuta, Ghatia, Gararia, Itala, Wagaicha, Tambesara and Talwara villages of Banswara district. The Mn associated rocks in the study area are phyllite, schist, quartzite and limestone. The mineral assemblage in phyllite formed under greenschist facies metamorphism. Petrographic studies of various phyllite samples also reveal that porphyroblasts of biotite sat in the fine-grained micaceous matrix (Biotite, muscovite, chlorite) along with quartz, opaque and ore minerals. Petrographic studies of schist reveal its formation under prograde metamorphism. Mineral assemblages observed in schist are typical of greenschist to lower amphibolite facies. The various schist samples at places show clusters made up of perfect rhombshaped garnets which suggest the increase in the grade of metamorphism. The quartzites are disposed conformably with the phyllites, and are at times brecciated and re-cemented by secondary chert and manganese. These Mn-bearing quartzites are with sutured/serrated and straight grain boundaries. The quartzite samples are fully composed of quartz showing undulose extinction with subordinate feldspar, micas and carbonatic materials. The petrographic characteristics explain that mostly limestones are the dolomitic composition but some ferruginous varieties are also noticed at places. The purer variety of limestone consists of calcite, dolomite and some magnetite but tremolite, quartz and some minute flakes of biotite also occur in impure variety.
Prospects for Complex Use of Phosphate Ores Mineral Resources
Bouhenguel Mustapha,Amirech Abdelkrim,Bouchemma Ahcene,Merabet Djoudi
Asian Journal of Information Technology , 2012,
Abstract: The phosphate ores with siliceous and carbonated gangue are characterized by an unstable chemical composition and a high content of insoluble deposits. The aim of this study elaboration the working out of a separation technological diagram that would allow obtaining conditioned products from rough phosphate ore. The process used is flotation. The principal minerals which are included in the mineralogical composition are the phosphate, the dolomite, the calcite as well as the quartz and are used in the chemical industry for obtaining finished products.
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