Journal articles: 'Mineral replacement'

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Putnis, A. "Mineral Replacement Reactions." Reviews in Mineralogy and Geochemistry 70, no. 1 (January 1, 2009): 87–124. http://dx.doi.org/10.2138/rmg.2009.70.3.

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Blake, Jennifer M., Eamonn D. Ryan, Lesley F. Beaumont, and Colin E. Webber. "Changes in spine and radius bone density during long-term hormone replacement." Canadian Journal of Physiology and Pharmacology 77, no. 7 (August 1, 1999): 505–9. http://dx.doi.org/10.1139/y99-051.

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Lumbar spine and mid-radius bone mineral density was measured repeatedly in 48 postmenopausal women who completed 7 years of taking either a 500 mg·day-1 calcium supplement (n = 22) or calcium supplementation with hormone replacement therapy. The hormone replacement was either a low dose (n = 15) or a moderate dose (n = 11) regime. The purpose of the measurements was to establish the long-term pattern of change in bone mineral mass produced by continued hormone replacement. The calcium-only group lost bone mineral mass at the radius, while at the spine, bone was preserved. Low dose hormone replacement preserved radius bone. Moderate dose replacement increased bone mineral mass at the spine and preserved radius bone.Key words: calcium supplementation, long-term hormone replacement, lumbar spine bone mineral density, radius bone mineral density.

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Hartnett, Phoebe, Laura Boyle, Bridget Younge, and Keelin O’Driscoll. "The Effect of Group Composition and Mineral Supplementation during Rearing on Measures of Cartilage Condition and Bone Mineral Density in Replacement Gilts." Animals 9, no. 9 (August 30, 2019): 637. http://dx.doi.org/10.3390/ani9090637.

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Lameness is a major cause of poor longevity and poor welfare in replacement gilts. The problem is exacerbated by inappropriate housing and diet during the rearing period. Replacement gilts are often reared with male finisher pigs destined for slaughter. If they are not castrated, they perform high levels of potentially injurious sexual and aggressive behaviour. Furthermore, finisher pig diets are not designed to meet the needs of developing gilts and may not supply the necessary minerals to support good limb health. The objective of this study was to evaluate the effect of supplementing the diet of replacement gilts with copper, zinc and manganese and separating them from males during the rearing period on locomotory ability, bone mineral density and cartilage lesion scores. A 2 × 2 factorial design experiment investigated the effect of female-only or mixed-sex rearing, with or without supplementary minerals (Copper, Zinc and Manganese). In total, 384 maternal line gilts were assigned to 32 pens of 12 and were locomotion scored during the rearing period. A sub-sample (n = 102) of gilts were culled at breeding age and the front right limb was removed at slaughter. Areal bone mineral density (aBMD) was measured using dual energy X-ray absorptiometry, after which the limb was dissected to score the condition of the cartilage. The addition of trace minerals to the diet resulted in increased aBMD in the humerus (P < 0.05) compared to the control diet. Rearing gilts in female-only groups reduced the number of cartilage lesions overall (P < 0.05), and on the humeral condyle (P < 0.05). Rearing replacement gilts in female-only groups and with mineral supplementation had benefits for limb health.

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Sarmili, Lili, and Johanes Hutabarat. "INDICATION OF HYDROTHERMAL ALTERATION ACTIVITIES BASED ON PETROGRAPHY OF VOLCANIC ROCKS IN ABANG KOMBA SUBMARINE VOLCANO, EAST FLORES SEA." BULLETIN OF THE MARINE GEOLOGY 29, no. 2 (February 15, 2016): 91. http://dx.doi.org/10.32693/bomg.29.2.2014.69.

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The presence of mineral alteration or secondary processes to rocks on submarine volcano of Abang Komba was caused by an introduction of hydrothermal solutions. Those are indicated by the presence of a resembly of minerals alteration seen in their petrographic analyses. They are characterized by replacement partially surrounding of plagioclase phenocrysts, partially replacing plagioclase by sericite, carbonate and clay minerals. The replacement of pyroxene partly by chlorite, and the presence of albitisation (secondary albite) contained in fine rectangular plagioclase sized. Other fitures occasionally observed by the presence of partial oxidation of ore minerals and the presence of quartz, and epidote as an alteration from plagioclase and pyroxene. Keywords : alteration, resembly of minerals alteration, oxidation, submarine vulcano of Abang Komba. Gejala alterasi atau proses-proses sekunder yang terjadi pada batuan di gunung bawah laut Abang Komba adalah disebabkan oleh introduksi larutan hidrotermal. Semua ini ditunjukkan dengan kehadiran kumpulan mineral ubahan yang terlihat dalam sayatan batuan. Kumpulan mineral ini dicirikan dengan adanya penggantian sebagian yang mengelilingi fenokris plagioklas, penggantian sebagian plagioklas oleh serisit, karbonat dan mineral lempung. Penggantian sebagian piroksen oleh klorit, dan adanya gejala albitisasi (albit sekunder) yang terdapat pada plagioklas berbentuk balokan yang berukuran halus. Gejala lainnya yang kadang-kadang teramati adanya oksidasi sebagian dari mineral bijih dan hadirnya kuarsa, serta epidot sebagai hasil ubahan plagioklas dan piroksen. Kata kunci : alterasi, kumpulan mineral ubahan, oksidasi, gunung bawahlaut Abang Komba.

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Valero, Alicia, Antonio Valero, and Adriana Domínguez. "Exergy Replacement Cost of Mineral Resources." Journal of Environmental Accounting and Management 1, no. 2 (June 2013): 147–58. http://dx.doi.org/10.5890/jeam.2013.05.004.

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Li, Kan, Allan Pring, Barbara Etschmann, Edeltraud Macmillan, Yung Ngothai, Brian O’Neill, Anthony Hooker, Fred Mosselmans, and Joël Brugger. "Uranium scavenging during mineral replacement reactions." American Mineralogist 100, no. 8-9 (August 2015): 1728–35. http://dx.doi.org/10.2138/am-2015-5125.

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Trotter, Andreas, Ludwig Maier, Hans-Jörg Grill, Thomas Kohn, Matthias Heckmann, and Frank Pohlandt. "Effects of Postnatal Estradiol and Progesterone Replacement in Extremely Preterm Infants." Journal of Clinical Endocrinology & Metabolism 84, no. 12 (December 1, 1999): 4531–35. http://dx.doi.org/10.1210/jcem.84.12.6180.

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The fetus is supplied from the placenta with estradiol (E2) and progesterone (P) in increasing amounts during gestation. After delivery of a premature infant, placental supply is disrupted, resulting in a rapid decrease in E2 and P. Replacement of these placental hormones may restore intrauterine conditions and may be beneficial for bone mineral accretion, clinical course, and outcome. Thirty female infants with a median gestational age of 26.6 weeks (between 24.1–28.7) and a birth weight of 675 g (370–990) were randomized to receive E2 and P replacement, aiming to maintain plasma levels equaling the intrauterine levels, or no replacement. The E2 and P replacement was started iv and was followed by transepidermal administration for a total duration of 6 weeks. Repeated measurements included plasma levels of E2, P, FSH, and LH; uterine volume; calcium and phosphorus in spot urine specimens; and bone mineral accretion by single photon absorption densitometry. Further, the incidence of chronic lung disease and various clinical outcome data were recorded. The plasma levels of E2 and P were within the intrauterine range with median replacements of 2.30 mg/kg·day E2 (1.13–6.23) and 21.20 mg/kg·day P (11.23–27.36), iv. Three- and 6-fold higher doses of E2 and P were needed via the transepidermal route. The uterine volumes increased, and FSH and LH as indicators for biological effectiveness were significantly lowered with replacement. The bone mineral accretion rates tended to be higher, and the incidence of chronic lung disease tended to be lower (0% vs. 29%; P = 0.097). E2 and P replacement via iv and transepidermal routes is capable of maintaining plasma levels as high as those in utero with biological effectiveness. Trends toward improved postnatal bone mineral accretion and less chronic lung disease were found with the hormone replacement. Further and more extensive studies are warranted to address the role of this new approach in the care of extremely premature infants.

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Kim, Byung Chun, Hye Won Ro, Yeun Sung Jung, In Sang Yoon, Soon Ju Jeong, Min Ho Park, Jung Han Yoon, and Young Jong Jegal. "Bone Mineral Density in Postsurgical Thyroxine Replacement." Korean Journal of Endocrine Surgery 6, no. 1 (2006): 1. http://dx.doi.org/10.16956/kjes.2006.6.1.1.

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Andrusova, N. N., E. S. Zhavoronok, O. A. Legon’kova, A. S. Goncharova, and S. A. Kedik. "Polymer–Mineral Compounds for Cementless Hip Replacement." Polymer Science, Series D 13, no. 1 (January 2020): 68–72. http://dx.doi.org/10.1134/s1995421220010037.

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Heath, Hunter. "Thyroxine Replacement Therapy and Bone Mineral Density." Mayo Clinic Proceedings 64, no. 2 (February 1989): 264–65. http://dx.doi.org/10.1016/s0025-6196(12)65687-0.

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Ao, T., and J. Pierce. "The replacement of inorganic mineral salts with mineral proteinates in poultry diets." World's Poultry Science Journal 69, no. 1 (March 1, 2013): 5–16. http://dx.doi.org/10.1017/s0043933913000019.

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Al-Hammod, Amer A., Qais J. Frayyeh, and Waleed A. Abbas. "Thermally Activated Bentonite As a Supplementary Cementitious Material – A Review." Engineering and Technology Journal 39, no. 2A (February 25, 2021): 206–13. http://dx.doi.org/10.30684/etj.v39i2a.1733.

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Bentonite is a mixture of clay and non-clay minerals. Montmorillonite clay mineral is a dominant mineral in bentonite. Silica and alumina bond in the crystal structure of montmorillonite. Therefore, they cannot contribute to the pozzolanic reaction. Heat treatment of bentonite leads to the destruction of the crystal structure of montmorillonite and converting silica and alumina to reactive phases. Thermally activated bentonite (TAB) is a relatively low reactive pozzolan when used as partial replacement of Portland cement modifies both fresh and hardened properties of cement paste, mortar, and concrete. The most desired effects of TAB are: improve segregation resistance, reduce the rate of strength gain, and enhance concrete durability against sulfates, chlorides, and acids, in addition to economic and ecological beneficiations. This paper provides information related to heat treatment of bentonite clays and montmorillonite minerals, and their effects on the paste, mortar, and concrete when used as a partial replacement of Portland cement.

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Alshaeri, Heba K., Zuhair S. Natto, Serena Tonstad, Ella Haddad, and Karen Jaceldo-Siegl. "Effect of dried California Mission figs on mineral status and food replacement." Public Health Nutrition 18, no. 6 (August 22, 2014): 1135–40. http://dx.doi.org/10.1017/s1368980014001566.

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AbstractObjectiveFigs are a rich source of several different minerals and fibres. We studied the effect of the consumption of dried California Mission figs on mineral and nutrient levels, as well as the effect of the addition of figs to a self-selected habitual diet on dietary patterns.DesignA crossover randomized controlled trial study design in which participants with a mean of age of approximately 56 years were randomly assigned to eat either their usual diet for 5 weeks or to add dried California Mission figs (120 g/d) to their usual diet for 5 weeks, after which they crossed over to the other group for an additional 5 weeks. Six 24 h dietary recalls and four blood samples were obtained from each participant.SettingLoma Linda University School of Public Health, USA.SubjectsA follow-up study using data collected from eighty-eight American males and females from September to December 2008.ResultsDiets reported in the 24 h dietary recall during the fig-supplemented diet period were significantly higher in Ca and K in the dietary and total phase (P value<0·05). Nevertheless, data on mineral levels in the body gathered by means of biochemical analyses from blood samples were nearly the same for both the figs-added and the participants’ standard diet. The estimated displacement suggests that eating figs resulted in the elimination of 4 % of desserts, 5 % of vegetables, 10 % of dairy products, 23 % of grain products and 168 % of beverages from other sources that participants would otherwise consume.ConclusionsBased on 24 h dietary recalls, the daily consumption of figs may increase the intake of several different minerals. However, mineral levels in blood samples were not altered significantly.

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Perova, Elena, Anatoly Zaitsev, John Spratt, Nataliya Vlasenko, Nataliya Vladimirovna Platonova, and Olga Bubnova. "Thermodynamic analysis of primary and secondary minerals stability in melilite-nephelinite tuff with Australopithecus Afarensis footprints, Laetoli, Tanzania." Vestnik of Saint Petersburg University. Earth Sciences 67, no. 2 (2022): 227–42. http://dx.doi.org/10.21638/spbu07.2022.202.

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The Laetoli area in northern Tanzania is an important palaeo-anthropological site, where the oldest footprints of Australopithecus afarensis reside. Aeolian tuffs are the major rock type at Laetoli and they are divided into Lower and Upper Laetolil Beds that were deposited at an interval of 4.36 and 3.63 million years. The Upper Laetolil Beds contain eight layers of air-fall tuffs known as marker tuffs. The Australopithecus afarensis footprints are observed on the surface of the white tuff, which is a part of the Upper Laetolil marker tuff 7, also known as the “Footprint Tuff.” The interpolated age of the marker tuff 7 is 3.66 million years. Two mineral assemblages are distinguished in the Upper Laetolil marker tuffs. The first assemblage consists of primary tuff minerals and includes clinopyroxene (diopside, augite, aegirine-augite), nepheline, melilite (åkermanite and alumoåkermanite), garnet (andradite and schorlomite), magnetite, and others. The second mineral assemblage consists of secondary minerals, montmorillonite, calcite, and phillipsite. They were formed during replacement of the primary minerals, volcanic glass, and ash cementation. Thermodynamic calculations show that the major primary tuff minerals (melilite and nepheline) are stable at variable sodium activity and pH values. Replacement of melilite and nepheline by montmorillonite is caused by a decrease of sodium activity in slightly alkaline, neutral and acidic conditions (рН < 10). Montmorillonite is not present in the altered nephelinitic tuff of the Sadiman volcano (which is considered as a source of the Laetolil Beds) where kaolinite is the major secondary mineral. This is explained by the difference in H2O fugacity with higher lgfH2O values in Sadiman and lower values in Laetoli. Relationships between primary and secondary tuffs minerals on the lgaHCO3 vs pH plot suggest mineral transformation within the Laetolil Beds in slightly acid and neutral con- ditions (рН = 5–7) compared with more alkaline conditions at Sadiman (рН > 10).

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Leggo, P. J., J. J. Cochemé, A. Demant, and W. T. Lee. "The role of argillic alteration in the zeolitization of volcanic glass." Mineralogical Magazine 65, no. 5 (October 2001): 653–63. http://dx.doi.org/10.1180/002646101317018479.

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AbstractThe pseudomorphic replacement of glass shards by zeolite minerals is a common feature of volcanoclastic sediments. In the majority of cases the initial stage of this reaction is the alteration of the glass surface to a clay mineral or celadonite after which the bulk of the glass is altered to zeolite. This replacement feature is seen particularly well in glass of rhyolitic composition; the zeolite mineral usually being clinoptilolite. Volcanoclastic rocks of Oligocene age exposed in the Rhodope Massif, Bulgaria offered an opportunity to study this reaction experimentally as rocks containing unaltered glass shards are known to be close stratigraphic equivalents of zeolitized tuffs and in this respect are considered to be precursor rocks. Low-temperature hydrothermal reactions conducted on the unaltered glass, which had been clay coated in the laboratory, demonstrates the importance of the clay-glass interface. An hypothesis is put forward to explain this type of zeolitization process and a distinction is drawn between these rocks and other sediments in which zeolite minerals form from volcanic glass without the presence of a clay interface.

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Putnis, A. "Mineral replacement reactions: from macroscopic observations to microscopic mechanisms." Mineralogical Magazine 66, no. 5 (October 2002): 689–708. http://dx.doi.org/10.1180/0026461026650056.

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AbstractMineral replacement reactions take place primarily by dissolution-reprecipitation processes. Processes such as cation exchange, chemical weathering, deuteric alteration, leaching, pseudomorphism, metasomatism, diagenesis and metamorphism are all linked by common features in which one mineral or mineral assemblage is replaced by a more stable assemblage. The aim of this paper is to review some of these aspects of mineral replacement and to demonstrate the textural features they have in common, in order to emphasize the similarities in the underlying microscopic mechanisms. The role of volume change and evolution of porosity is explored both from natural microtextures and new experiments on model replacement reactions in simple salts. It is shown that the development of porosity is often a consequence of mineral replacement processes, irrespective of the relative molar volumes of parent and product solid phases. The key issue is the relative solubility of the phases in the fluid phase. Concepts such as coupled dissolution-precipitation, and autocatalysis are important in understanding these processes. Some consequences of porosity generation for metamorphic fluid flow as well as subsequent crystal growth are also discussed.

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pei, xun, lujie liu, geng wang, minqi wang, and Minyan huai. "291 Effects of replacing inorganic trace minerals with low level of organic trace minerals on growth performance, tissue mineral deposition and mineral excretion in piglets." Journal of Animal Science 97, Supplement_3 (December 2019): 120. http://dx.doi.org/10.1093/jas/skz258.248.

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Abstract This study was conducted to investigate effects of inorganic trace mineral (ITMs) replacement with low level organic trace minerals (glycine complex minerals, GCMs; proteolytic complex minerals, PCMs) on growth, tissue mineral retention and mineral excretion in piglets. A total of 128 weaned piglets (Duroc × Landrace × Largewhite, 14.37 ± 0.32kg BW) aged 40d were randomly divided into 4 dietary treatments and fed for 28 days, with 4 replicates of 8 piglets per treatment. Dietary treatments were:(T1) basal + ITMs (Cu, Zn, Fe and Mn, sulfate) at 100% commercial level;(T2) basal + ITMs at 50% commercial level + GCMs at 50% commercial level;(T3) basal + GCMs at 50% commercial level;(T4) basal + PCMs at 50% commercial level respectively. On day 29, six piglets from each group were slaughtered to collect serum, muscle and organ samples. The results showed that ADG of T1, T2 and T3 was higher than that of T4 (P < 0.05), FCR of T1, T2 and T3 was lower than that of T4 (P < 0.01). The retention of trace minerals in tissues and serum is significantly correlated with the supplemental level and source of trace minerals. When 50% commercial level ITMs replaced with GCMs, Cu in serum, heart, liver and pancreas, Fe in liver and muscle was increased (P < 0.05), and liver Zn, Mn in heart, liver and muscle was increased (P < 0.01) respectively. Muscle Zn in T3 was higher than that from T4 (P < 0.05) with same level of organic minerals. Zn, Fe, Mn excreted from urine in pigs fed T2 diet was less than that from T1 (P < 0.05), and urine Zn in T3 treatment is lower than that from T4 (P < 0.05). This study indicated that dietary ITMs replacement with GCMs resulted in higher tissue minerals deposition, and organic trace minerals from GCMs exhibited higher bioavailability than those from PCMs.

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El Nemr, Amr Maher, Maha Ahmed Shawky, and Mahmoud El Khafif. "The Effect of Mineral Pigments on Mechanical Properties of Concrete." Journal of Civil Engineering and Construction 11, no. 3 (August 15, 2022): 139–52. http://dx.doi.org/10.32732/jcec.2022.11.3.139.

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Pigmented concrete exhibits artesian properties in addition to ordinary concrete properties, explicitly high strength, excellent durability, and weather resistance. However, the influence of several parameters that affect the characteristics of colored concrete should be studied; extensively. In this paper, the impact of the w/b (water/binder) ratio using color pigments on the mechanical properties such as compressive and flexural strengths of colored cement mortar prisms and cubes experimentally investigated. The experimental program included 21 mixes with six cubes and three flexural prisms specimens for assessing compressive and flexural strength, respectively. The blends included different water/binder ratios with values of 0.4, 0.5, and 0.6, in addition to several color pigments as a partial replacement of cement. The percentage of replacements altered between 0, 2.5%, 5% and 7.5% with two different shades of pigments consisting of red iron and green chromium oxide. Based on the experimental results, empirical expressions were generated based on Abram’s law to assess the relationship between the compressive strength of colored concrete and w/b ratio. The results revealed that the compressive and flexural strength of colored concrete is influenced by w/b ratio and partially replacement percentage of cement by color pigment not proportionally direct. Furthermore, the shade of pigments also has a different impact as well.

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Zhang, Li Feng, Jun Ying Lai, Xiao Qian Qian, and De Long Hu. "Influence of Mineral Admixtures on early Shrinkage of Ordinary Concrete." Advanced Materials Research 450-451 (January 2012): 135–39. http://dx.doi.org/10.4028/www.scientific.net/amr.450-451.135.

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In this paper the influence of mineral admixtures on early shrinkage of ordinary concrete with the same water-binder ratio is studied by self-made equipment and CABR-NES deformation instrument developed by China Academy of Building Research Institute. All concrete specimens are cured with one surface exposed to air and others are covered with plastic film. The replacement ratio of mineral admixtures is 10%, 20% and 30%, respectively, and a mixture of a combination of both fly ash and slag is also studied. The results indicate fly ash reducing the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is above 20%. Slag also reduces the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is below 20%. Mixture with a combination of both fly ash and slag has lower shrinkage than mixture with fly ash.

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Reinhardt, Jürgen. "Tracking mineral replacement in metamorphic rocks using optical and chemical fingerprints of pre-existing minerals: an example of retrograde Al2 SiO5 transformation." European Journal of Mineralogy 23, no. 5 (December 1, 2011): 795–803. http://dx.doi.org/10.1127/0935-1221/2011/0023-2116.

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Sastry, K. V. S. Gopala Krishna, A. Ravitheja, and T. Chandra Sekhara Reddy. "Effect of Foundry Sand and Mineral Admixtures on Mechanical Properties of Concrete." Archives of Civil Engineering 64, no. 1 (May 17, 2018): 117–31. http://dx.doi.org/10.2478/ace-2018-0008.

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Abstract Foundry sand waste can be utilized for the preparation of concrete as a partial replacement of sand. The strength properties of M25 grade concrete are studied with different percentages of replacement of fine aggregates by foundry sand at 0%, 10%, 20%, 30%, 40%, and 50%. The optimum percentage of foundry sand replacement in the concrete corresponding to maximum strength will be identified. Keeping this optimum percentage of foundry sand replacement as a constant, a cement replacement study with mineral admixtures such as silica fume (5%, 7.5%, 10%) and fly ash (10%, 15%, 20%,) is carried out separately. The maximum increase in strength properties as compared to conventional concrete was achieved at 40% foundry sand replacement. Test results indicated that a 40% replacement of foundry sand with silica fume showed better performance than that of fly ash. The maximum increase in strengths was observed in a mix consisting of 40% foundry sand and 10% silica fume. SEM analysis of the concrete specimens also reveals that a mix with 40% foundry sand and 10% silica fume obtained the highest strength properties compared to all other mixes due to the creation of more C-H-S gel formations and fewer pores.

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Subash, Narayanan, Siva Avudaiappan, Somanathan Adish Kumar, Mugahed Amran, Nikolai Vatin, Roman Fediuk, and Radhamanohar Aepuru. "Experimental Investigation on Geopolymer Concrete with Various Sustainable Mineral Ashes." Materials 14, no. 24 (December 10, 2021): 7596. http://dx.doi.org/10.3390/ma14247596.

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The aim of this research was to find the best alternative for river sand in concrete. In both geopolymer concrete (GPC) and cement concrete (CC), the fine aggregates are replaced with various sustainable mineral ashes, and mechanical and durability tests are conducted. Specimens for tests were made of M40 grade GPC and CC, with five different soil types as river sand substitute. The materials chosen to replace the river sand are manufactured sand (M-sand), sea sand, copper slag, quarry dust, and limestone sand as 25%, 50%, 75%, and 100%, respectively by weight. GPF50 and CC50 were kept as control mixes for GPC and CC, respectively. The test results of respective concretes are compared with the control mix results. From compressive strength results, M-sand as a fine aggregate had an increase in strength in every replacement level of GPC and CC. Additionally, copper slag is identified with a significant strength reduction in GPC and CC after 25% replacement. Copper slag, quarry dust, and limestone sand in GPC and CC resulted in considerable loss of strength in all replacement levels except for 25% replacement. The cost of GPC and CC is mixed with the selected fine aggregate replacement materials which arrived. Durability and cost analyses are performed for the advisable mixes and control mixes to have a comparison. Durability tests, namely, water absorption and acid tests and water permeability and thermal tests are conducted and discussed. Durability results also indicate a positive signal to mixes with M-sand. The advisable replacement of river sand with each alternative is discussed.

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Bacon, Siobhan, and Rachel Crowley. "Developments in rare bone diseases and mineral disorders." Therapeutic Advances in Chronic Disease 9, no. 1 (November 24, 2017): 51–60. http://dx.doi.org/10.1177/2040622317739538.

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In the last decade, there have been a number of significant advances made in the field of rare bone diseases. In this review, we discuss the expansion of the classification system for osteogenesis imperfecta (OI) and the resultant increase in therapeutic options available for management of OI. Bisphosphonates remain the most widely used intervention for OI, although the effect on fracture rate reduction is equivocal. We review the other therapies showing promising results, including denosumab, teriparatide, sclerostin, transforming growth factor β inhibition and gene targeted approaches. X-linked hypophosphataemia (XLH) is the most common heritable form of osteomalacia and rickets caused by a mutation in the phosphate regulating endopeptidase gene resulting in elevated serum fibroblast growth factor 23 (FGF23) and decreased renal phosphate reabsorption. The traditional treatment is phosphate replacement. We discuss the development of a human anti-FGF23 antibody (KRN23) as a promising development in the treatment of XLH. The current management of primary hypoparathyroidism is replacement with calcium and active vitamin D. This can be associated with under or over replacement and its inherent complications. We review the use of recombinant parathyroid hormone (1–84), which can significantly reduce the requirements for calcium and vitamin D resulting in greater safety and quality of life for individuals with hypoparathyroidism. The use of receptor activator of nuclear factor κB ligand infusions in the treatment of a particular form of osteopetrosis and enzyme replacement therapy for hypophosphatasia are also discussed.

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Xue, Peng, Yan Wang, Jie Yang, and Yukun Li. "Effects of Growth Hormone Replacement Therapy on Bone Mineral Density in Growth Hormone Deficient Adults: A Meta-Analysis." International Journal of Endocrinology 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/216107.

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Objectives. Growth hormone deficiency patients exhibited reduced bone mineral density compared with healthy controls, but previous researches demonstrated uncertainty about the effect of growth hormone replacement therapy on bone in growth hormone deficient adults. The aim of this study was to determine whether the growth hormone replacement therapy could elevate bone mineral density in growth hormone deficient adults.Methods. In this meta-analysis, searches of Medline, Embase, and The Cochrane Library were undertaken to identify studies in humans of the association between growth hormone treatment and bone mineral density in growth hormone deficient adults. Random effects model was used for this meta-analysis.Results. A total of 20 studies (including one outlier study) with 936 subjects were included in our research. We detected significant overall association of growth hormone treatment with increased bone mineral density of spine, femoral neck, and total body, but some results of subgroup analyses were not consistent with the overall analyses.Conclusions. Our meta-analysis suggested that growth hormone replacement therapy could have beneficial influence on bone mineral density in growth hormone deficient adults, but, in some subject populations, the influence was not evident.

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Taguchi, Tomomi, Takuya Toki, Akinori Hayashi, and Koji Takano. "A Case With Adult GH Deficiency Complicated With Osteogenesis Imperfecta: Effect of GH Replacement on Bone Mineral Density." Journal of the Endocrine Society 5, Supplement_1 (May 1, 2021): A564. http://dx.doi.org/10.1210/jendso/bvab048.1149.

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Abstract Background: Osteogenesis imperfecta (OI) is an inherited connective tissue disorder with many phenotypic presentations. Bisphosphonates are the mainstay of pharmacologic fracture prevention therapy, although they aren’t officially approved for the treatment of OI. Clinical Case: The patient was born by breech delivery. After he had multiple fractures at the age of two years, he was diagnosed with osteogenesis imperfecta (OI) type I by genetic analysis (c.1299 + 1G> A mutation in the COL1A1 gene). On the growth curve, his height fell below -2SD at the age of six years. When he was 12 years old, he visited another hospital because of short stature (Hight 119 cm: -2.7SD). Pituitary MRI revealed pituitary stalk disruption and pituitary atrophy. Endocrinological examinations (ITT, TRH, LHRH, arginine stimulation tests) showed severe GH deficiency. Growth hormone replacement therapy was started. At the age of 16 years, he was diagnosed to have central hypothyroidism and central diabetes insipidus, and levothyroxine and DDAVP were started. His bone mineral density of the lumbar spine was 0.546 g/cm2, and alendronate was started. At the age of 17, central hypogonadism was diagnosed by LHRH stimulation test, and HCG injections were initiated. His bone mineral density continued to increase by GH replacement, HCG injections and bisphosphonate and reached 0.820 g/cm2 (Z-score: -0.27) by the age of 18 years. GH replacement was discontinued (final height 180 cm). At that age, his bone mineral density declined to 0.717 g/cm2 at the age of 25 years, although he stayed on an alendronate and HCG injections. At that time, total testosterone 890 ng/dL (142<n<923 ng/dL) was within normal range, but IGF-1 level was below the lower limit (44 ng/mL; -4.6SD, 225<n<337 ng/mL). He was referred to our hospital for transition to adult endocrine care. Endocrinologic evaluation revealed low serum cortisol level in the early morning (2.26 µg/dL, 7.07<n<19.6 μg/dL). GH-releasing peptide-2 stimulation test revealed severe GH deficiency (peak GH 0.18 ng/mL, n> 15 ng/mL (1)) and replacements with GH and hydrocortisone were initiated. After the GH replacement, the bone mineral density started to increase to 0.954 g/cm2 (Z-score: -0.5). Conclusion: So far as we know, this is the first case report of OI with panhypopituitarism treated with GH and bisphosphonate. This case suggests that bisphosphonate alone is not sufficient to maintain bone mineral density complicated with both OI and severe GHD. GH replacement therapy was inevitable to increase bone mineral density in this patient. Reference: (1) Kazuo Chihara et al. A simple diagnostic test using GH-releasing peptide-2 in adult GH deficiency. Eur J Endocrinol.2007;157;19-27.

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Friis, Henrik. "First occurrence of moskvinite-(Y) in the Ilímaussaq alkaline complex, South Greenland – implications for rare-earth element mobility." Mineralogical Magazine 80, no. 1 (February 2016): 31–41. http://dx.doi.org/10.1180/minmag.2016.080.047.

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AbstractMoskvinite-(Y), Na2K(Y,REE)Si6O15, is a rare mineral, which until now has only been described from its type locality Dara-i-Pioz, Tajikistan. At Ilímaussaq moskvinite-(Y) was discovered in a drill core from Kvanefjeld, where it occurs as a replacement mineral associated with a mineral belonging to the britholite group. The composition was determined by a combination of electron probe microanalysis and laser ablation inductively coupled plasma mass spectrometry analyses. The empirical formula based on 15 oxygens is Na1.94K0.99(Y0.94Yb0.03Er0.03Dy0.03Ho0.01Gd0.01)∑1.05Si5.98O15. The coexistence of an almost pure Y and a light rare-earth element (REE) mineral is interpreted as fractionation ofREEand Y during the replacement of an earlier formedREEmineral. Theoretical calculations of the observed replacement of feldspathoids by natrolite show that the generated fluid would have pH > 8, which inhibits large scale mobility ofREE. In addition, a K-Fe sulfide member of the chlorbartonite-bartonite group is for the first time observed in Ilímaussaq where it occurs where sodalite is replaced by natrolite and arfvedsonite by aegirine. The sulfide incorporates the S and some of the Cl generated by the alteration of sodalite, whereas the K and Fe originates from the replacement of arfvedsonite by aegirine.

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Gauthier, L., L. Dinh, and P. E. Beaulé. "Peri-acetabular bone mineral density in total hip replacement." Bone & Joint Research 2, no. 8 (August 2013): 140–48. http://dx.doi.org/10.1302/2046-3758.28.2000173.

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Hochberg, Z., A. Benderly, L. Kahana, and Z. Zadik. "MINERAL OCORTICOID REPLACEMENT IN 11β-HYDROXYLASE DEFICIENCY (11-OHD)." Pediatric Research 20, no. 11 (November 1986): 1201. http://dx.doi.org/10.1203/00006450-198611000-00166.

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Minde, Mona Wetrhus, Udo Zimmermann, Merete Vadla Madland, Reidar Inge Korsnes, Bernhard Schulz, and Sabine Gilbricht. "Mineral replacement in long-term flooded porous carbonate rocks." Geochimica et Cosmochimica Acta 268 (January 2020): 485–508. http://dx.doi.org/10.1016/j.gca.2019.09.017.

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Chokkalingam, Ramesh Babu, and Manikandan Rajakannu. "Performance Evaluation of Ordinary Portland Cement with GGBFS and Portland Slag Cement at Same GGBFS Replacement Level in Concrete." MATEC Web of Conferences 203 (2018): 06004. http://dx.doi.org/10.1051/matecconf/201820306004.

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Literature review indicates that the usage of mineral admixtures (Fly ash, Ground Granulated Blast Furnace Slag, Silica Fume and Rice Husk ash) significantly improves the durability of concrete structures. Though it is reported as best alternative materials for improving durability of concrete structures, it was not very well received in government projects in India till 1990. However, for the past two decades, the usage of mineral admixtures directly or in the form of blended cement in concrete have significantly increased. Major concern of using mineral admixtures which was persisting among majority of the Ordinary Portland Cement (OPC) users are (i) delayed setting and strength gain, affecting the rate of construction, (ii) inconsistent in quality of mineral admixtures, mostly happened in site blending (iii) no established results pertains to Indian condition. In India, mostly the usage of mineral admixtures in concrete are used as a replacement for OPC, specifically in Ready Mix Concrete and site batching plant. However, few literature have reported that usage of mineral admixtures in the form of blended cement which is made at cement manufacturing plant by either intergrinding or blending will exhibits better concrete properties due to consistent quality and better quality control practice followed. Hence, the authors have undertaken this study to investigate the performance of mineral admixtures (only GGBFS) as direct replacement materials and as blended cement in concrete. In order to understand in detail, both as replacement of OPC and in the form of PSC, was undertaken on various cement content in concrete, i.e., 300, 320, 340, 360, 380 kg/m3. Results of compressive strength at various age of curing indicates that usage of GGBFS in the form of Portland Slag Cement (PSC) shows better performance than as a replacement of OPC in concrete.

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Pecušová, Beáta, Mariana Pajtášová, Zuzana Mičicová, Darina Ondrušová, Andrea Feriancová, Marcel Kohutiar, and Ivan Labaj. "Study of clay minerals effect on curing characteristics of polymer blends and physical-mechanical properties of prepared vulcanizates." MATEC Web of Conferences 157 (2018): 07010. http://dx.doi.org/10.1051/matecconf/201815707010.

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The given paper deals with the study of the properties of clay minerals, namely montmorillonite and moreover, it is focused on effect of these clay minerals on the curing characteristics of the polymer blends and the physical-mechanical properties of prepared vulcanizates. Montmorillonite is a major clay mineral which has a wide application in many industrial branches. It belongs to the group of dioctahedral smectite minerals with structural type in the ratio of 2:1. Characteristics of prepared modified and organomodified clay minerals are based on sulphur vulcanisation accelerators which are used for the preparation of real polymer blend where they represent a partial replacement of the common carbon black filler and then, the effect on the curing characteristics of polymer blends as well as physical-mechanical properties of the prepared vulcanizates are investigated. The results exhibit that the clay-based filler (modified and organomodified clay minerals) can be used as a partial replacement while the quality of the prepared blends is preserved.

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Gao, Gui Bo, Chun Xiang Qian, and Yong Wei Wang. "Effect of Fly Ash and Slag Powder on Coefficient of Thermal Expansion of Concrete." Advanced Materials Research 374-377 (October 2011): 1230–34. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1230.

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In order to study the effect of fly ash (FA) and slag powder (SP) on coefficient of thermal expansion (CTE) of concrete, the influence of FA and SP to CTE of concrete was compared, the influence of replacement proportion of FA to CTE of concrete was tested, and the unhydrate mineral admixture particles were observed with SEM and validate with Energy Spectrometry. The results showed that the influence of FA and SP to CTE of concrete is different, the CTE of SP concrete is near to the norm concrete，but is higher than the FA concrete; With the replacement proportion of FA increased, the CTE of concrete decreased; The per strength CTE increased obviously when the replacement proportion exceed 10%, and the decrease of strength badly when the replacement proportion of FA exceed 30%; The unhydrate mineral admixture particles is one of the most important factors that influence the CTE of concrete, and the mineral admixture could influence the composite and the microstructure of cement paste, then cause the change of porosity and density.

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Mohamad, Madzura, Mohd Noor Mazlee, and Shamsul Baharin Jamaludin. "Sand Replacement Materials (SRM) in Sustainable Cement Composites; A Concise Review." Advanced Materials Research 795 (September 2013): 91–95. http://dx.doi.org/10.4028/www.scientific.net/amr.795.91.

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This paper presents a short review of research works on the development of sustainable cementitious matrix composites with addition of potential mineral wastes as sand replacement materials. The study emphasizes on the possibility of recycling and sustain the mineral wastes from natural and industrial by-products in order to reduce the consumption of natural resources, energy and cost, and at the same time to reduce the environmental pollution. The aim of this review is to share the ideas and present the findings from previous works undertaken to evaluate the suitability of mineral wastes as a sand replacement materials to produce sustainable and durable construction materials in the future.

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Murzin, Valery, Galina Palyanova, Татiana Mayorova, and Tatiana Beliaeva. "The Gold–Palladium Ozernoe Occurrence (Polar Urals, Russia): Mineralogy, Conditions of Formation, Sources of Ore Matter and Fluid." Minerals 12, no. 6 (June 16, 2022): 765. http://dx.doi.org/10.3390/min12060765.

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We studied the mineralization and sulfur isotopic composition of sulfides of gold–palladium ores in olivine clinopyroxenites from the Dzelyatyshor massif made up of a continuous layered series of rocks: olivine-free clinopyroxenite–olivine clinopyroxenite–wehrlite. The primary igneous layering of rocks, manifested as different quantitative ratios of clinopyroxene and olivine in them, controls the local trends of variability in the chemistry of mineral-forming medium and the concentrations of ore components, including noble metals, and sulfur in each separate layer during its cooling. The replacement of primary rock-forming minerals by secondary minerals, when the temperature decreases, is a characteristic trend for pyroxenites: (a) olivine → serpentine, secondary magnetite, and (b) clinopyroxene → amphibole, secondary magnetite → chlorite. The deposition of native gold in parageneses with PGM and sulfides at the Ozernoe occurrence took place during the replacement of earlier rock-forming minerals by chlorite. This process completed mineral formation at the deposit and took place at temperatures 150–250 °С and at the high activity of S, Te, Sb, and As of fluid. The variability of mineral formation conditions during chloritization is reflected in the change of native-sulfide forms of Pd by arsenide-antimonide forms and the sulfur isotopic composition of sulfides. The Pd content in native gold increases in the series—Au-Ag solid solution (<1.5 wt.% Pd)—Au-Cu intermetallides (to 6 wt.% Pd)—Cu-Au-Pd solid solutions (16.2–16.9 wt.% Pd). The sulfur isotopic composition of pyrite, chalcopyrite, and bornite varies from −2.1 to −2.9‰. It is assumed that a deep-seated magmatic basic melt was the source of fluid, ore components, and sulfur.

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Hainin, Mohd Rosli, Putra Jaya Ramadhansyah, Tan Huan Chan, Abdul Hassan Norhidayah, Fadzli Mohamed Nazri, and Ichwana. "Strength and Properties of Concrete Pavement Incorporating Multiple Blended Binders." Materials Science Forum 889 (March 2017): 265–69. http://dx.doi.org/10.4028/www.scientific.net/msf.889.265.

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This study investigated the effects of multiple blended binders on the properties and performance of concrete pavement. Mineral admixtures, namely, silica fume, metakaolin, and rice husk ash, are used to replace ordinary Portland cement at replacement levels of 0% (control mix), 5%, 10%, and 15% by mass-to-mass basis. The performance of the multiple binders on the concrete pavement properties was evaluated based on compressive strength, strength reduction, and strength activity index. Results showed that the mineral admixtures can be satisfactorily used as cement replacement materials to increase the properties of pavement concrete. Moreover, concrete pavements with 5% and 10% replacement levels exhibited excellent performance with good strength.

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Cao, Zhong-lu, Zhong-chun Su, Makoto Hibino, and Hiroki Goda. "Effects of Mineral Admixtures on Macrocell Corrosion Behaviors of Steel Bars in Chloride-Contaminated Concrete." International Journal of Corrosion 2022 (August 17, 2022): 1–12. http://dx.doi.org/10.1155/2022/3332123.

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Based on the macrocell corrosion theory and by alternating the microcell corrosion state and macrocell corrosion state, the influence of mineral admixtures, such as fly ash, slag, and limestone powder, on the macrocell corrosion behaviors of steel bars embedded in chloride-contaminated concrete were investigated and clarified. The results indicated that the inhibition effect induced by slag on macrocell corrosion and microcell corrosion was obviously better than that induced by fly ash or limestone powder. The presence of slag in chloride-contaminated concrete could remarkably decrease the corrosion area ratios of anodic steel, even if the replacement levels of slag to cement reached 70%. With the addition of mineral admixtures into concrete, the ratio of macrocell current density to microcell current density was decreased to some extent, depending on the types, replacement levels, and replacement ways of mineral admixtures. The use of slag and fly ash in chloride-contaminated concrete can effectively weaken the macrocell corrosion and make the corrosion be dominated by microcell corrosion. The types and replacement levels of mineral admixtures also had a remarkable influence on the control mode of macrocell corrosion. The use of slag was more effective than that of fly ash or limestone to weaken the cathode control mode of macrocell corrosion and made the control mode of macrocell corrosion be dominated by jointed control.

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TUFEANU, Roxana E., Mihaela A. TIȚA, and Ovidiu TIȚA. "Muffins Obtained with Some Vegetal Powders as Fat Replacers." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies 75, no. 1 (May 19, 2018): 21. http://dx.doi.org/10.15835/buasvmcn-asb:000317.

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Chia seeds and watermelon rind powder were used to produce low-fat muffins in which butter has been replaced at different levels.The utilization of the fat replacers has increased the moisture content and water activity of the samples. The initial moisture content was ranging from 24.41% in control sample to 31.89% in muffins with 100% butter replacement by using the watermelon rind paste. The water activity presented values between 0.863-0.899 during storage at ambient temperature for 10 days. Minerals analysis indicated that through the addition of the powders, an increase in the mineral content of the samples can be achieved. P was the most abundant mineral followed by K. The samples obtained by replacing the butter with vegetal powders can provide between 49.29 % - 58.51% phosphorus; 18.91 %-21.45% selenium and 15.04%-18.48% manganese from the recommended daily intake. These vegetal powders can be used as ingredients for partial or total replacement of fat in muffins due to their ability to improve the nutritional quality and to maintain the physical-chemical and sensory characteristics at level of acceptability.

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38

Wagner, Thomas, and Nigel J. Cook. "Mineral reactions in sulphide systems as indicators of evolving fluid geochemistry – a case study from the Apollo mine, Siegerland, FRG." Mineralogical Magazine 61, no. 407 (August 1997): 573–90. http://dx.doi.org/10.1180/minmag.1997.061.407.09.

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AbstractThe textural and paragenetic relationships of sulphide and sulphosalt minerals within Cu-Pb-Sb-Bi hydrothermal vein mineralization at the Apollo mine, Siegerland, Germany, are interpreted in terms of various reaction sequences. An earlier primary sulphide mineralization hosted within a siderite vein of the Siegerland type, with pyrite, chalcopyrite, sphalerite and galena as main component phases, has been overprinted by Sb-, Bi- and Cu-rich fluids. This superposition resulted in the formation of new quartz-stibnite veins, and various mineral reactions with the primary sulphides including the formation of the sulphosalt minerals semseyite, tetrahedrite, meneghinite, jaskolskiite, boulangerite, bournonite and zinkenite. Based on microprobe analyses of reaction pairs and determination of mineral proportions in some cases, a series of quantitative data for each mineral reaction may be generated. This, in turn, allows for the construction of isocon diagrams permitting the relative mobility and immobility of all chemical elements involved in each reaction to be discussed. Two stages of reactive replacement are identified, characterized by immobile behaviour of S and supply of Sb and Cu during the first stage and relative immobility of S and Sb with no further supply of metals during the second stage. Formation of sulphosalts inside the siderite vein during the first stage is interpreted as a decrease of disequilibrium between hydrothermal fluids and pre-existing vein minerals. Replacement processes of the second stage are interpreted as an equilibration of geochemical contrasts between different points within the siderite vein and also between the siderite and quartz-stibnite vein systems. The geochemical evolution of fluid composition during the entire mineralizing event may therefore be modelled, based on the transfer of chemical components reflected in the succession of mineral reactions. Such an approach has applications to comparable polyphase mineralization sequences, in which an understanding of fluid evolution patterns may greatly assist in the development of genetic models for mineral deposits. Solid-state diffusion and grain-boundary diffusion are considered to be the dominant mechanisms for short-range mass transport, whereas diffusion of ionic and complex species through the fluid is considered to be of major importance in long-range mass transport.

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Мырзабеков, Б. Э., Э. М. Ли, Т. Э. Гаипов, and А. Б. Маханбетов. "STUDY OF THE MATERIAL COMPOSITION OF THE SAMPLE MANGANESE-CONTAINING ORE DEPOSITS “KARAMOLA”." SERIES CHEMISTRY AND TECHNOLOGY 6, no. 444 (December 15, 2020): 95–101. http://dx.doi.org/10.32014/2020.2518-1491.103.

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In this work, the material composition of the ore of the Karamola Deposit is studied. A sample of manganese ore from the Karamola Deposit with a size of 0-120 mm was received for research on the material composition. The manganese mineralization of the sample is represented by the mineral series polyanite-pyrolusite and WADA-psilomelane. Mineral secretions are crystalline earthy structures and mixed formations. Manganese oxides are distributed almost throughout the entire mass of the rock. They are represented by crystallized gel formations, soot, and skeletal structures. Ore gels permeate the rock through cracks, cleavages, leaching voids, pores, cleavage planes and penetrate between the scales of layered minerals and form a variety of forms in the mass of the rock: individual strokes, thread-like cuts, veins, edges, layers, nests. Replacement solutions are siliceous or manganese-siliceous in nature and color the rock in the corresponding color with mineral microparticles: black – manganese, red and red – iron. Rock-forming minerals are mainly represented by quartz. The granulometric composition of an ore sample crushed to the minus 2.0+0 mm class was determined.

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Lin, Bing Xia, Ming Guo Deng, and Xu Wen Liang. "Characteristic Analysis of Texture and Structure of Ores and Genesis of Luziyuan Pb-Zn Polimetallic Deposit in Zhenkang, Yunnan, China." Advanced Materials Research 734-737 (August 2013): 311–15. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.311.

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The main ore structure of the deposit include: disseminated structure, emulsion droplet-like structure, banded structure, vein-like structure, the massive structure, brecciated structure, etc.; The main ore texture include: crystalline granular texture, the replacement texture, solid solution separation texture, interstitial texture, etc. According to the ore fabric characteristics and metal minerals and gangue mineral combination, type and shape since the degree and mineral in space analysis of characteristics of the relationship, the mining area can be roughly divided into three periods: sedimentary diagenesis stage, the initial formation of the sources, hydrothermal reformation metallogenic stage and supergene stage. It was considered that Luziyuan Pb-Zn polymetallic deposit is the hydrothermal deposits for early deposition, the late hydrothermal transformation.

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41

G. E., Stradivari, I. B. G. Partama, and I. G. N. G. Bidura. "THE EFFECT OF POLLARD REPLACEMENT WITH RICE BRAN SUPPLEMENTED MULTIVITAMIN-MINERAL IN RATION ON THE PERFORMANCE CROSSBRED PIG." Majalah Ilmiah Peternakan 22, no. 2 (June 28, 2019): 55. http://dx.doi.org/10.24843/mip.2019.v22.i02.p03.

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The purpose of this study is to determine the effect of pollard replacement with rice bran supplementedmultivitamin-mineral in ration on the performance of crossbred pigs. The design used a randomized block design(RBD) consists of 3 treatments and 4 groups as replications. The treatments A (control): pollard in ration withoutmultivitamin-mineral supplementation, B: ration with rice bran without multivitamin-mineral supplementation,C: ration with rice bran which supplemented with 0.20% multivitamin-mineral. The variables observed were finalbody weight, weight gain, feed consumption, FCR, protein, crude fiber, and fat consumption.The results showedthat the ration with rice bran supplemented with 0,20% multivitamin-mineral were able to produce the same finalweight, weight gain, and FCR with the control and increase significantly crude fiber consumption 45,57 g/h, 85,63g/h of fat consumption, and decrease 207,64 g/h protein consumption. However, the feed consumption showed nosignificant differences in each treatment. It can be concluded that pollard replacement with rice bran supplementedwith 0,20% multivitamin-mineral in ration fed to crossbred pigs can produce similar production performance ascontrol, and increase consumption of crude fiber, and fat consumption.

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Alshaaer, Mazen, Juma’a Al-Kafawein, Ahmed S. Afify, Nagat Hamad, Ghassan Saffarini, and Khalil Issa. "Effect of Ca2+ Replacement with Cu2+ Ions in Brushite on the Phase Composition and Crystal Structure." Minerals 11, no. 10 (September 22, 2021): 1028. http://dx.doi.org/10.3390/min11101028.

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The gradual replacement of Ca2+ with Cu2+ ions in brushite (CaHPO4·2H2O) has been extensively studied and discussed. The approach adopted in this work has not been systematically explored in previous studies. This novel approach may prove beneficial for the production of Ca1−xCuxHPO4·nH2O materials with desired properties suitable for medical applications. Solutions of sodium dihydrogen orthophosphate dihydrate, NaH2PO4·2H2O, calcium nitrate tetrahydrate, Ca(NO3)2·4H2O, copper nitrate trihydrate, Cu(NO3)2·3H2O, ammonium hydroxide solution, and diluted HCl were used for the preparation of these materials. At low Cu/Ca molar ratios (up to 0.25) in the starting solution, biphasic phosphate minerals were formed: brushite and sampleite. When the Cu/Ca molar ratio increases gradually from 0.67 to 1.5, sampleite-like mineral precipitates. Powdered XRD (X-ray diffraction), thermogravimetric (TG) analysis, and SEM (scanning electron microscopy) techniques were employed for the study of the microstructure of the produced materials for different degrees of Ca replacement with Mg. It is found that the Cu/Ca ratio in the starting solution can be adjusted to obtain materials with tailored composition. Thus, a new method of sampleite-like synthesis as a rare mineral is introduced in this study. Both phosphate minerals brushite and sampleite-like minerals are attractive as precursors of bioceramics and biocements. The search for such products that may decrease the possibility of post prosthetic or implant infection can be crucial in preventing devastating post-surgical complications.

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Ming Wei, Ong, and Norsuzailina Mohamed Sutan. "The Influence of Finely Ground Mineral Admixture (FGMA) on Efflorescence." Journal of Civil Engineering, Science and Technology 4, no. 1 (April 1, 2013): 50–55. http://dx.doi.org/10.33736/jcest.108.2013.

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Efflorescence phenomenon on concrete is not new and found in the form of white deposits on surfaces of concrete. Incorporation of Finely Ground Mineral Admixture (FGMA) in concrete to prevent occurrence of efflorescence is based on reduction of portlandite, densified microstructure and thus enhanced watertightness. The magnitude of efflorescence in term of percentage of calcium carbonate formation of FGMA modified mortar were evaluated at water-cement ratio of 0.3, 0.4 and 0.5 with 10%, 20%, and 30% of cement replacement by weight. The samples were tested with chemical analysis at 7, 14, 21, 28, 60 and 90 days. The FGMA additions into mortar were comparing with ordinary mortar to evaluate enhanced performance of FGMA modified mortar toward efflorescence. The results of this experiment showed that addition of FGMA into mortar caused less formation of calcium carbonate as partial replacement of cement with certain w/c ratio and percentage of cement replacement.

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Rosén, Thord, Tommy Hansson, Hans Granhed, Janos Szucs, and Bengt-Åke Bengtsson. "Reduced bone mineral content in adult patients with growth hormone deficiency." Acta Endocrinologica 129, no. 3 (September 1993): 201–6. http://dx.doi.org/10.1530/acta.0.1290201.

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Bone mineral content was measured in a follow-up study of adult patients with hypopituitarism and growth hormone deficiency. There were 95 patients (59 males, mean age 54.0 years, range 21–74 years; 36 females, mean age 53.5 years, range 31–73 years). Routine replacement therapy with cortisone acetate and l-thyroxine was given. All males that were gonadal deficient were on proper testosterone therapy, except in four patients who were treated separately. Bone mineral content (g/cm) was measured using dual-photon absorptiometry in the third lumbar vertebra. Bone mineral content in the patients was compared with a control population (N=413, 25–74 years of age). Bone mineral content was significantly lower in males (N= 55, p<0.05) compared with controls. In females, bone mineral content was significantly lower both among the subjects with untreated gonadal deficiency (p<0.001) and among those with treated gonadal deficiency and normal premenopausal gonadal function (p<0.005) compared with controls. To summarize, patients with hypopituitarism on routine replacement therapy but not growth hormone have a lower bone mineral content than the controls. The reduced bone mineral content might be a result of untreated growth hormone deficiency.

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Kempe, U., J. Götze, S. Dandar, and D. Habermann. "Magmatic and metasomatic processes during formation of the Nb-Zr-REE deposits Khaldzan Buregte and Tsakhir (Mongolian Altai): Indications from a combined CL-SEM Study." Mineralogical Magazine 63, no. 2 (April 1999): 165–77. http://dx.doi.org/10.1180/002646199548402.

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AbstractCathodoluminescence (CL) imaging and spectroscopy, as well as backscattered electron imaging, were used to assign the occurrence of several mineral phases and rock structures in altered nordmarkites and calcite-bearing granites from the Nb-Zr-REE deposits from Khaldzan Buregte and Tsakhir (Mongolian Altai) to three events: (1) intrusion of barren nordmarkites; (2) intrusion of small bodies of calcite-bearing granites with metasomatic alteration of the wall-rocks; and (3) alteration by F-rich fluids.Unusual red and yellow CL caused by Fe3+ and Mn2+ emission centres were detected in microcline and albite. Fe3+ centres were also established (along with others) in quartz, zircon, and possibly in fluorite.Magmatic and metasomatic rock structures and internal structures of the minerals coexist in the samples. The primary magmatic features were in part preserved during alteration. In contrast, the internal and the centre structures may be changed during alteration even in non-replaced mineral phases. Euhedral minerals may be formed by secondary processes as shown for lath-shaped albite. The occurrence of pseudomorphs, the inheritance of elements during replacement, and the mechanical effects of secondary minerals on earlier mineral phases during metasomatic growth are proposed as criteria for the reconstruction of the mineral succession in altered rocks. Snowball structures may be formed as a result of metasomatic alteration rather than as a magmatic intergrowth.

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Avasthi, Alka A. "Water Requirement of Concrete with Mineral Admixtures." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 30, 2021): 4573–77. http://dx.doi.org/10.22214/ijraset.2021.36021.

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India is one of the leading producers of sugar and rice, hence agricultural waste is generated in huge quantities in India leading to potential disposal problems without effective management techniques. However, the economic importance of this solid waste has been realised with several applications like adsorbents, filters, ceramics, briquettes, bricks, and blocks and soil amendment activities. Cement is one of the most universally used material. Cement production is an environmental threat as well as the production cost is also very high. Manufacturing of cement and its use is also one of the causes of global warming Environmentalists and Researchers around the world are searching for better options to replace cement As cement replacement materials mineral admixtures are nowadays gaining mileage as they address two problems. First is the waste management of agricultural wastes, which causes air pollution due to open air burning and the second is reducing the demand for cement. Hence in addition to reducing the cost it also reduces the hazardous effect that it has on the environment. In general, the particle size of these admixtures play an important role in making the concrete dense, but low particle size leads to increased surface area and more requirement their surface area increases and workability reduces. Hence to make the concrete workable the water requirement also increase [1].Generally the water requirement or the water cement ratio for normal concrete is between 0.35 to 0.5 , depending on the cement content and the mix design . For high strength concrete where the quantity of cement increases the water cement ratio also increases. But in concrete with mineral admixtures the water cement ratio is more than 0.6. The present paper deals with the water requirement for the concrete with cement replacement with mineral admixtures , The two types of admixtures water requirement of concrete with partial replacement of cement with sugarcane bagasse ash and rice husk ash in different proportions of 5 % , 10%, 15% , 20%, 25% and 30 % , earlier as a binary mix replacing the mineral admixtures individually and later together as a ternary mix using both the mineral admixtures together. The results indicate increase in water content with the increase in cement replacement proportions in both the binary and ternary mix . The increase in water content does not hamper the compressive strength of the binary and ternary mix , but in some cases increases it.

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ANKITA, ANKITA, A. K. VERMA, PUTAN SINGH, and ASIT DAS. "Effect of multi-nutrient liquid supplement on serum minerals and hormone profile in buffalo heifers." Indian Journal of Animal Sciences 88, no. 4 (April 17, 2018): 453–57. http://dx.doi.org/10.56093/ijans.v88i4.78813.

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Eighteen Murrah buffalo heifers (average BW of 290±2.5 kg) were randomly distributed into three groups of six each in an experiment based on randomized block design to investigate the effect of partial replacement of concentrate mixture with molasses based multi-nutrient liquid supplements (MMLS) on serum mineral and reproductive hormonal profile. During 240 d of experimental period, all animals were supplied with green forages (2 kg DM/d) and wheat straw ad libitum. Animals in group T1 (control) were fed a concentrate mixture (maize 40, wheat bran 40, soyabean meal 17, mineral mixture 2, and salt 1%) to meet their nutrient requirements. However, 20% of the concentrates were replaced with MMLS and MMLS plus in groups T2 and T3, respectively. Blood was collected on d 0, 120 and 240 days of experiment to evaluate serum mineral and reproductive hormonal (progesterone and estradiol) profile. Serum concentrations of Ca, P, Fe and Mn were similar among the groups. Serum concentration of Cu and Zn was higher in groups T2 and T3. Concentrations of progesterone and estradiol were similar among the groups, but showed an increasing trend on day 240. It was concluded that partial replacement of concentrate mixture with MMLS and MMLS plus improved Cu and Zn status without any adverse impact on other minerals and reproductive hormone profile.

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Camilleri DDS, MSc, PhD, Josette. "Is Mineral Trioxide Aggregate a Bioceramic?" Odovtos - International Journal of Dental Sciences 18, no. 1 (March 17, 2016): 13. http://dx.doi.org/10.15517/ijds.v18i1.23482.

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Bioceramics are a subset of biomaterials and define ceramic materials, which are biocompatible. The range of biocompatibility is wide from totally inert materials to fully resorbable materials that are fully replaced with time. The first mention of Bioceramics in Endodontics referred to a study on a new material Bioaggregate, which was developed as a replacement for mineral trioxide aggregate (MTA) boasting a Portland cement free formulation. But is MTA a bioceramic?.

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Lazić, Predrag, Đurica Nikšić, and Dejan Stojanović. "Replacement of old flotation cells in the flotation plant of the Lece mine." Tehnika 76, no. 1 (2021): 27–31. http://dx.doi.org/10.5937/tehnika2101027l.

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Russian made FPM-GMO-1.6 flotation machines were previously installed for primary stage flotation concentration of lead and zinc minerals in Lece flotation plant. For cleaning stage FMR-10 flotation machines were in use. Beside low technological characteristic, hard maintenance and worn out are characteristic of this machines. In order to modernize the production and eliminate the above shortcomings primarily in the process of lead minerals flotation, in 2020, the old flotation cells were replaced with new ones. Currently, 8 new RCS-5 cells for coarse and scavengel flotation of lead minerals and 4 RCS-3 cells for cleaning of coarse lead mineral concentrate are working on the lead flotation line in Lece flotation. These cells were produced by Metso Minerals from Finland. Flotation cells, which are installed, have modern technical - technological characteristics, with all the accompanying equipment for automatic control of pulp levels and air consumption. This paper presents comparative characteristics of old and new flotation cells, their appearance and characteristics and technological results achieved in flotation with old and new cells.

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García, Nitza M., Hildélix L. Soto-Toro, Mauricio Cabrera-Ríos, and Oscar Marcelo Suárez. "Optimal Cement Mixtures Containing Mineral Admixtures under Multiple and Conflicting Criteria." Advances in Civil Engineering 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/3780810.

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In modern construction industry, fabrication of sustainable concrete has turned the decision-making process into a challenging endeavor. One alternative is using fly ash and nanostructured silica as cement replacements. In these modern mixtures, proper concrete bulk density, percentage of voids, and compressive strength normally cannot be optimized individually. Hereby, a decision-making strategy on the replacement of those components is presented while taking into account those three performance measurements. The relationships among those components upon concrete fabrication required a design of experiments of mixtures to characterize those mineral admixtures. This approach integrates different objective functions that are in conflict and obtains the best compromise mixtures for the performance measures being considered. This optimization strategy permitted to recommend the combined use of fly ash and nanosilica to improve the concrete properties at its early age.

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Journal articles on the topic 'Mineral replacement'

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