secondary minerals

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The Impact of Secondary Phyllosilicate Minerals on the Engineering Properties of Various Igneous Aggregates from Greece

The Impact of Secondary Phyllosilicate Minerals on the Engineering Properties of Various Igneous Aggregates from Greece

compressive strength (Figure 7b) suggesting that these phyllosilicate minerals are the determinant factors among the other minerals (primary and non phyllosilicate secondary minerals) influencing the mechanical performance of aggregates. Figures 7a and 7b support the interpretation mentioned above in figure 6, because these phyllosilicate minerals, due to their platy and layered character, form foliated masses which lead to the development of larger pores and open surfaces which are responsible for mechanically weaker rocks as these areas disturb the cohesiveness of rock’s structure. In the studied ultramafic rocks, the secondary phyllosilicate minerals due to their low hardness in conjunction with their phyllosilicate structure create different microroughness. As can be seen in figure 4, with decreasing alteration (i.e. decreasing contents of secondary phyllosilicate minerals) (Table 1) the surface of the particles appears rough microroughness (Figure 4). This is explained by the platy and soft nature of phyllosilicate minerals and mainly by serpentine structure. The low microtopography results in considerable reduce of mechanical properties which hence influence the engineering constructions, because the smooth surfaces of the particles of ultramafic rocks, due to low microroughness, do not favor strong adherence with the cement paste in the concrete [22].
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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture-infilling and other secondary minerals, As an analogue for the behaviour of th[r]

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Physichochemical Properties and Trace Elements of Soils in Mambilla Plateau of Northeastern Nigeria

Physichochemical Properties and Trace Elements of Soils in Mambilla Plateau of Northeastern Nigeria

brown. The hue is 2.5, 5 and 7.5, value is between 5, 6 and chroma 1, 2 and 6 respectively. The yellow and reddish colours displayed by some samples may be due to high iron oxides present in the soil samples. [25, 26]. The development and distribution of colours may be due to the extensive and various minerals that results from chemical and biological weathering, especially redox reaction. The primary minerals in soil parent material are weathered and thus the elements combine into new and colourful compounds, forming secondary minerals with a yellow or red colour, the soil organic matter also decomposes into black and brown
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Influence of Clay Minerals on Some Soil Fertility Attributes: A Review

Influence of Clay Minerals on Some Soil Fertility Attributes: A Review

Clay minerals are naturally inorganic compounds with definite physical, chemical and crystalline properties and are classified as primary or secondary, silicates or non-silicates and crystalline or amorphous [6]. Primary minerals form at elevated temperatures and pressures, and are usually derived from igne- ous or metamorphic rocks, while secondary minerals are the culmination of ei- ther alteration of the primary mineral structure or neoformation through preci- pitation or recrystallization of dissolved constituents into a more stable structure [7] [8]. Common primary minerals in soil environments include silicates, oxides of Fe and Al, Zr and Ti, and phosphates, while typical secondary minerals found in soil environments include alumino-silicates, oxides and hydroxides, carbo- nates, sulphates and amorphous minerals [6]. Secondary minerals are mainly found in the clay-sized and fine-silt-sized fractions, and form the most reactive inorganic materials in soils [9], thereby influencing availability of nutrient ele- ments through various mechanisms. Soil clay minerals are grouped into 1:1 and 2:1 clay minerals, depending on the ratio of silica tetrahedral sheet to alumina octahedral sheet. The 1:1 clay minerals, primarily kaolinite, are found in most soils, but predominate in highly weathered soils of humid tropical regions. In tropical environments, sesquioxide minerals rich in Fe and Al dominate. The 2:1 swelling or expandable clays include the smectite and vermiculite groups, which have large surface areas and high cation exchange capacities (CEC). These clay minerals play a significant role in dictating the suitability and behaviour of soil for various land uses. Clay mineralogy-soil fertility relationship is an imperative component in understanding and managing soil fertility for sustaining crop production, especially in the tropics [10] [11].
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Mantle melting versus mantle metasomatism   “the chicken or the egg” dilemma

Mantle melting versus mantle metasomatism “the chicken or the egg” dilemma

1998; Sobolev et al., 1999; Spetsius and Taylor, 2002). Given the high concentrations of incompatible elements (both LILE and high- fi eld- strength elements) found in these secondary minerals, the traditional approach is to attribute crystallisation of the secondary mineral assem- blage to modal and cryptic metasomatism prior to the kimberlite magma percolation, to in-situ partial melting due to in fi ltration of meta- somatic fl uids and/or to interaction with the kimberlitic magma itself (e.g. Misra et al., 2004; Spetsius and Taylor, 2002). All of these scenarios are plausible; however, none of them explain the nature and origin of the metasomatic fl uids, which are evidently abundant in K, Na, Cl, Ca, Ti, Ba, CO 2 , H 2 O, LREE and other highly incompatible components. More-
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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture·infilling and other secondary minerals, As an analogue for the behaviour o'f t[r]

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Formation of Fe- and Mg-Rich Smectite under Hyperalkaline Conditions at Narra in Palawan, Philippines

Formation of Fe- and Mg-Rich Smectite under Hyperalkaline Conditions at Narra in Palawan, Philippines

decides smectite or zeolite as secondary minerals after alkaline alteration of bentonite might be 409. whether nuclei of M-S-H and/or F-S-H will be formed or not[r]

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Naturotherapies Based on Minerals

Naturotherapies Based on Minerals

The application of cold water on particular external parts of the body causes superficial vasoconstriction (ex- pressed by paleness), tachycardia and hyperpnoea. After application, a secondary vasodilatation and the increase of muscular tonus occur. On the other hand, the applica- tion of warm water causes superficial vasodilatation (ex- pressed by redness or blushing), low arterial pressure, muscular relaxation and sedation. Taking bath in warm or in cold mineral water has many beneficial health ef- fects, because it conditions blood circulation through the multi-layer human skin. For instance, the primary bene- fits of heat include: blood vessels dilatation, nervous terminals excitation, breathing acceleration and facilita- tion and increase of urea production.
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Reagent Adsorption on Phosphates pdf

Reagent Adsorption on Phosphates pdf

Adsorption of surfactants on minerals is the basic process governing S otation. It is controlled by various physicochemical processes in the pulp involving inter- actions among the mineral particles, surfactants, dis- solved inorganics, solvent species and other additives such as polymers. Adsorption can be considered as selective partitioning of the surfactant adsorbate into the interfacial region, resulting from the more ener- getically favourable interactions between the adsor- bate and the solid than those between the former and the species in the bulk solution. The interactions leading to adsorption include chemical bonding, elec- trostatic interaction, desolvation of the surfactant po- lar group and the mineral surface species, hydrogen bonding, van der Waals interactions, etc.
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Effects of Water Intake on Biochemical Parameters and Performance During Resistance Exercise

Effects of Water Intake on Biochemical Parameters and Performance During Resistance Exercise

The study aims to determine whether water intake during resistance training impacts the amounts of potassium (K+), sodium (Na+), magnesium (Mg), and calcium (Ca) and to identify the effects of the reactions of these minerals on performance. Ten male university students aged between 20 and 23 participated in the study. The participants did five different previously-determined resistance exercises (3 sets of 8RM). During the training program, the participants did the resistance exercises by not consuming water in the first week and consuming water in the second week. (Pre-exercise and exercise days routine food and fluid intake was maintained, fluid intake restriction was applied only during exercise) The participants’ weight, body mass index (BMI), percent body fat, systolic and diastolic pressure, lactate, Borg scale ratings, and K+, Na+, Mg, and Ca were determined before and after the exercises. Training volume was recorded. Performing the exercises without water intake produced a significant increase in K+. During the exercises done with water intake, there was a significant increase in Na+. No statistical differences were determined in the volume of exercise done with and without water intake. The study shows that water intake during high-intensity resistance training does not have any effect on the volume of exercise. In addition, the changes in Na+ and K+ parameters do not affect the volume of exercise. Although loss of minerals is statistically significant in exercise without water, it is understood that the total amount of minerals lost is not enough to induce a physiological change or a performance change in the total resistance training volume. Water, regardless of the volume and intensity of exercise, promotes balance of metabolism and prevents performance degradation that can occur during sport events (Murray et al., 1991). For this reason, water should be consumed not only in sports activities but also in daily activities.
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Oil, Gas, and Minerals

Oil, Gas, and Minerals

Oil, Gas, and Minerals SMU Law Review Volume 38 Issue 1 Annual Survey of Texas Law Article 9 1984 Oil, Gas, and Minerals Eric T Laity Follow this and additional works at https //scholar smu edu/smulr[.]

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Cost effective minerals

Cost effective minerals

The cost of the supplementation of the minerals through the water supply varied throughout the season depending on the dose rate at the time. The average cost for the programme over the year for the minerals selenium, copper, zinc, cobalt and iodine was 0.84 cents/cow/day. The higher dose periods during September, October and November averaged approximately 0.96 cents/cow/day.

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Infrared Spectroscopic Detection of biosignatures at Lake Tírez, Spain: implications for Mars

Infrared Spectroscopic Detection of biosignatures at Lake Tírez, Spain: implications for Mars

In astrobiology, minerals and organic molecules are inti- mately linked: minerals provide surfaces to support, con- centrate, and preserve organic molecules, and act as templates for prebiotic reactions. This work focuses on sulfates, a class of hydrated minerals detected on Mars. Sulfates have been mapped by the ESA Mars Express OMEGA instrument (Arvidson et al., 2005; Bibring et al., 2005; Gendrin et al., 2005) and the Compact Reconnaissance Imagine Spectro- meter for Mars (CRISM) on board Mars Reconnaissance Orbiter (MRO) (Pelkey et al., 2007; Wiseman et al., 2010), and detected by the NASA rovers (Squyres et al., 2004; Gellert et al., 2006; Morris et al., 2006; Ehlmann and Ed- wards, 2014; McAdam et al., 2014). Varieties identified in- clude iron sulfates (such as jarosite and ferricopiapite), magnesium sulfates (such as kieserite), and calcium sulfates (such as gypsum, basanite, and anhydrite). Among these, Ca- sulfates are more stable under martian conditions compared to other varieties. They have been found in veins and the lower strata of Mount Sharp at Gale Crater (Grotzinger et al., 2012; Nachon et al., 2014; Vaniman et al., 2014; Rapin et al., 2016), at Endeavor Crater, the Columbia Hills at Gusev Crater (Squyres et al., 2006; Yen et al., 2008), and at the North and South Poles of Mars. Sulfates are also not just restricted to ancient terrains; the well-mixed dust that covers most surfaces on Mars has high concentrations of sulfates, at an average concentration of 5.82 wt % (Gellert et al., 2004). In this paper, we report on the mid infrared (MIR) and near infrared (NIR) spectroscopic study of the hypersaline lake environment, Tı´rez Lake, in Spain. On Earth, hyper- saline environments impose severe stresses on endogenous microorganisms, such as high osmotic pressures and po- tentially low (aw *0.75) water activities (Grant, 2004). Despite this, life has been found surviving at an unexpected level of diversity over a wide range of salt concentrations (Ley et al., 2006). The potential of hypersaline environ- ments and the evaporitic minerals they precipitate to pre- serve life and its biomolecules over geologically significant timescales makes Tı´rez Lake a compelling habitat to in- vestigate biomolecular signatures, and for the search for life vestiges on Earth and beyond.
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Oil, Gas, and Minerals

Oil, Gas, and Minerals

Oil, Gas, and Minerals SMU Law Review Volume 39 Issue 1 Annual Survey of Texas Law Article 14 1985 Oil, Gas, and Minerals Eric T Laity Follow this and additional works at https //scholar smu edu/smulr[.]

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Oil, Gas, and Minerals

Oil, Gas, and Minerals

Oil, Gas, and Minerals SMU Law Review Volume 40 Issue 1 Annual Survey of Texas Law Article 14 1986 Oil, Gas, and Minerals Eric T Laity Follow this and additional works at https //scholar smu edu/smulr[.]

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Notes on Tasmanian minerals

Notes on Tasmanian minerals

with but never, so far as observation has gone, intermixed with the normal form although this is somewhat abundant in its usual adamantine characteristic habit, often shewing remarkably [r]

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Minerals from the ocean

Minerals from the ocean

Deposits of this second group include construction materials, some placer deposits, phosphorites, and glauconite, all of which are found primarily on the shelf and upper slope; and depos[r]

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Bone without minerals and its secondary mineralization in Atlantic salmon (Salmo salar): the recovery from phosphorus deficiency

Bone without minerals and its secondary mineralization in Atlantic salmon (Salmo salar): the recovery from phosphorus deficiency

Research that uses zebrafish ( Danio rerio ) as a model to study human bone diseases often does not distinguish between bone formation and mineralization given that only bone mineral density is measured. However, bone formation and bone mineralization are not the same. Techniques to visualize the extreme small bone elements in early zebrafish, Alizarin Red S whole-mount staining and micro CT, suffer from the same drawback as X-rays. Without oblique illumination (whole-mount staining) or contrasting agents (micro CT, X-rays) these techniques show only the mineralized phase of the bone (Bruneel and Witten, 2015; Witten et al., 2017). The fact is that during early bone formation in zebrafish, mineralization starts only 5 to 6 h after osteoid deposition (Cubbage and Mabee, 1996; Bird and Mabee, 2003). We are not aware of such data for teleost species that have larger individuals, for example, Atlantic salmon. In human bone, the delay of osteoid mineralization is the norm. Osteoid mineralization may start as late as 10 days after bone matrix formation (Boivin and Meunier, 2002). Although the 7-week mineralization delay that was enforced in this experiment is a much longer period, the principle appears to be the same. In the context of normal bone formation, bone matrix is produced first and mineralization happens later. Similar to the current findings, it is also possible to re-mineralize non-mineralized human bone matrix in the case of P-deficiency-related osteomalacia (Allen and Raut, 2004; Wilton et al., 1987). This and the findings of the present study underscore the distinction between bone formation and mineralization (Kyle, 1927; Beresford, 1981). The pattern of secondary mineralization raises questions about the role of osteoblasts in this process. If mineral deposition directly depends on osteoblasts, secondary mineralization in salmon should start in Deformation (mm)
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Cultural parameters influencing the production of antimicrobial metabolites by rhodococcus erythropolis vl rk 05

Cultural parameters influencing the production of antimicrobial metabolites by rhodococcus erythropolis vl rk 05

Microorganisms are capable of producing a broad spectrum of secondary metabolites, and the prokaryotic actinobacteria have most fruitful source of antibiotics, yielding 65-70% of all discovered antibiotics for the past five decades (Berdy, 2005). Therefore, screening of microorganisms for the production of new antibiotics continues to be an important iscovery programs. The class accounts for a high proportion of soil microbial biomass and contains the most economically significant prokaryotes, producing more than half of the bioactive . Actinobacteria belonging , in particular, are excellent producers. Emergence of drug resistance in many bacterial pathogens and the current increase in the number of fungal infections has caused a resurgence of interest in finding new active compounds (Samain et al., 1982). As the search for novel natural products continues, it of new compounds has decreased, whereas the rate of re isolation of known compounds is at increasing trend (Fenical . Recently, evidence has accumulated that rare actinomycete species, which are often very difficult to isolate e source of novel biologically
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Conflict Minerals and the Law of Pillage

Conflict Minerals and the Law of Pillage

The modern law of pillage makes it a crime, under the appropriate conditions, to appropriate property during a conflict with the intent to deprive the owner of th[r]

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