Mineralogical and chemical characteristics of five nontronites and Fe-rich smectites

Clay Minerals ◽  
1999 ◽  
Vol 34 (4) ◽  
pp. 579-599 ◽  
Author(s):  
H. M. Köster ◽  
U. Ehrlicher ◽  
H. A. Gilg ◽  
R. Jordan ◽  
E. Murad ◽  
...  
Keyword(s):  
Quadrupole Splitting ◽  
Infrared Spectra ◽  
The Other ◽  
Octahedral Coordination ◽  
Chemical Characteristics ◽  
Distinctive Features ◽  
Ambient Temperatures ◽  
The Third ◽  
Structural Formulae ◽  
Physical And Chemical

AbstractFive Fe–bearing dioctahedral smectites (three nontronites and two Fe-rich smectites) were purified using a variety of physical and chemical procedures. The structural formulae indicate one nontronite and one Fe-rich smectite to be montmorillonitic, whereas the other three smectites are beidellitic. Mössbauer spectra showed Fe to be exclusively trivalent and were fitted with three doublets, two of which had quadrupole splittings characteristic of Fe3+ in octahedral coordination, whereas the third had a distinctly lower quadrupole splitting. Although the position of the Si–O stretching band in the infrared spectra could reflect tetrahedral Fe3+, the lack of distinctive features prevented a definitive attribution of this component to tetrahedral Fe3+. The 18O/16O data suggest that fractionation of nontronite-water at ambient temperatures (1000 lnα = 23 ± 2‰) is lower than that of Fe-rich smectite (1000 lnα = 27 ± 2‰). The estimated formation temperatures of the samples are below 70°C.

scholarly journals Diagnosis and Recommendation Integrated System (DRIS) in Determining Mineral Status of Cotton in the Cotton Zones of Benin

2019 ◽  
pp. 1-13
Author(s):  
Isidore Amonmidé ◽  
Gustave D. Dagbénonbakin ◽  
P. B. Irénikatché Akponikpè ◽  
Emile C. Agbangba ◽  
Pierre G. Tovihoudji
Keyword(s):  
Nutrient Status ◽  
Nutrient Content ◽  
Integrated System ◽  
The Other ◽  
Chemical Characteristics ◽  
Cotton Yield ◽  
Seed Cotton ◽  
Seed Cotton Yield ◽  
Physical And Chemical ◽  
Made In

This study aimed at developing parameters of the Diagnosis and Recommendation Integrated System (DRIS) model for the assessment nutrient status for cotton grown in Benin.. Soil physical and chemical characteristics, leaves nutrient content (N, P, K, Ca, Mg) and seed-cotton yield were assessed on samples gathered from 150 farmers’ fields in 2018. Nutrient indices were computed using standard DRIS procedures. Results showed that phosphorus was in excess in the petiole and the whole leaves but in deficit in the limb. Potassium content was adequate according in the petiole and leaves but deficient in the limb. Ca content was limiting in the limb or the whole leaves and adequate in the petiole. Based on the diagnosis made in the petioles, Mg was deficient while adequate in the limbs and leaves. In the limb, the order of the macronutrients is as follows: K> P> N. On the other side, in the petiole and the whole leaves, the order of the macronutrients becomes: P> K> N. In the whole leaves and limb, the order of the secondary elements is as follows: Mg> Ca, whereas in the petiole the order of the secondary elements becomes: Ca> Mg.

scholarly journals Trophic relations between macroinvertebrates in the Vlasina river (Serbia)

2006 ◽  
Vol 58 (2) ◽  
pp. 105-114 ◽  
Author(s):  
M. Paunovic ◽  
Dunja Jakovcev-Todorovic ◽  
V. Simic ◽  
Bojana Stojanovic ◽  
Ana Petrovic
Keyword(s):  
Benthic Community ◽  
The Other ◽  
Trophic Relationships ◽  
Functional Feeding Groups ◽  
Chemical Characteristics ◽  
Trophic Relations ◽  
Faunal Composition ◽  
Feeding Groups ◽  
Physical And Chemical Characteristics ◽  
Physical And Chemical

The aim of the study presented was to define trophic relationships within the benthic community according to functional feeding groups (FFG) in the Vlasina River (Southeast Serbia), with an attempt to use those results to describe the watercourse. In an investigation performed during 1996, a total of 125 macrozoobenthic taxa were identified, 95 of which were included in FFG analyses. Although the investigated part of the river, in its physical and chemical characteristics, as well as characteristics of the benthofauna, generally corresponds to what could be expected, certain variations of faunal composition were observed along the river. Two groups of sites were separated by FFG analysis - sites on the upper section of the river and on a tributary (the Gradska River) comprised one group, while the remaining sites made up the other.

Experimental Investigation of the Effect of Materials and Their Surface Colours on Nocturnal Cooling

2013 ◽  
Author(s):  
Nnamdi V. Ogueke ◽  
Kevin N. Nwaigwe ◽  
Chidiebere Nwaiwu ◽  
Emmanuel E. Anyanwu
Keyword(s):  
Experimental Investigation ◽  
Relative Humidity ◽  
Temperature Difference ◽  
The Other ◽  
Galvanized Steel ◽  
Ambient Temperatures ◽  
Clear Night ◽  
The Third ◽  
Night Sky

The experimental investigation of the effects of materials and their surface colours on nocturnal cooling is presented. Two materials, galvanized steel and aluminium, were considered. Three plates of each material were used. One was painted black, the other white, while the third was left unpainted. Each of the plates (0.5 × 0.5 m) was used to cover a wooden box of dimension 0.5 × 0.5 × 0.24 m, made of 0.02 m thick plywood, thus producing an air tight arrangement. Six of such boxes were formed in all; three from galvanized steel and three from aluminium. Ambient temperatures, temperatures of the air inside the box and on the outside surface of the plates were measured between 19:00 hours and 06:00 hours for 6 months. Also measured was the relative humidity. Results obtained reveal that the plates’ performances greatly depended on how clear the night was. For very clear night, the black painted aluminium gave the best result, maintaining a temperature difference of 3–8°C with the ambient. For a partly overcast night, the best result of 1–5°C difference between the inside air and the ambient was recorded by the unpainted galvanized steel while on heavily overcast night the best performance came from the unpainted aluminium with a temperature difference of 1–4°C. Thus unpainted galvanized steel and aluminium are considered best in region where the night sky is hardly clear.

scholarly journals Nephrotoxicity of Bence-Jones proteins: correlation with endocytosis by BHK cells and intracellular movement

2001 ◽  
Vol 44 (2) ◽  
pp. 165-171
Author(s):  
Ana Lucia Nicastri ◽  
Elisa Maines Gomes ◽  
Maria José Brandão de Almeida Prado ◽  
Euthymia Brandão de Almeida Prado
Keyword(s):  
Sialic Acid ◽  
Culture Media ◽  
Calf Serum ◽  
The Other ◽  
Chemical Characteristics ◽  
Thin Sections ◽  
Bhk Cells ◽  
Physical And Chemical Characteristics ◽  
Physical And Chemical ◽  
Bence Jones Proteins

The aim of this investigation was to evaluate the endocytosis of two Bence-Jones proteins by renal cells in order to elucidate the interference of their physical and chemical characteristics on nephrotoxicity. Bence-Jones proteins (AK and GL) were purified and isolated from the urine of two patients with multiple myeloma. The isotype of both proteins was characterised as being human monoclonal lambda light chain. The AK protein presented mainly an Ip>7.0, a high content of galactose and a low amount of sialic acid molecules. On the other hand, the GL protein presented a single band with an Ip of 4.3, a higher level of sialic acid and a reduced amount of galactose, in comparison with the AK protein. Baby Hamster Kidney (BHK) cells were maintained in culture in bottles at 37ºC, using DMEM culture media supplemented with 10% of calf serum with a pH of 7.4. Once the monolayer was observed to be confluent, the BHK cells were incubated with the two proteins, dissolved in a serum-free medium for 1, 5, 15, 30, 60 minutes and 24 hours. Control cells were established omitting the incubation with Bence-Jones proteins, but maintaining all of the other conditions. After, this the cells were washed, trypsinised, centrifuged and fixed in a solution of 4% paraformaldehyde and 0.5% glutaraldehyde on a 0.1 M, pH 7.4 phosphate buffer. Cells were processed for immunocytochemical reactions by using protein A coupled with colloidal gold and further silver enhancement. Semi-thin sections of the pellets were obtained and submitted to the cytochemical reactions. Detection of labelling was made by using light microscopy. It was observed that GL protein tended to be directed towards a perinuclear position, whereas the AK protein tended to suffer lysosomal deviation, suggesting that there is a direct contribution of physical and chemical characteristics on intracellular direction taken by Bence-Jones proteins.

scholarly journals NATURAL BITUMEN OF GEORGIAN

World Science ◽  
2020 ◽  
Vol 1 (2(54)) ◽  
pp. 15-19
Author(s):  
Natela Khetsuriani ◽  
Esma Usharauli ◽  
Elza Topuria ◽  
Tamar Shatakishvili ◽  
Maka Kopaleishvili
Keyword(s):  
Elemental Composition ◽  
Chemical Characteristics ◽  
Natural Bitumen ◽  
Third Generation ◽  
The Third ◽  
Physical And Chemical Characteristics ◽  
Organic Extracts ◽  
Almost All ◽  
Physical And Chemical

Manifestations of natural bitumen are recorded in almost all regions of Georgia. The bitumen of Kari Crossing, Natanebi, Chibrevi, Baida, Polpoy-Teibi, Mirzaani and Kila-Kupra were studied. The main aromatic structures contained in organic extracts obtained from bitumen under investigation are identified, and physical and chemical characteristics, elemental composition and distribution of microelements in these organic extracts are determined. The study of microelements distribution showed that bitumen of the Kari Crossing and the Baida 2, in which the ratio V/Ni is less than 1 stratigraphically belong to the third-generation bitumen, and the Chibrevi and Mirzaani bitumen with the ratio V/Ni >1 is of older origin and belongs to Paleozoic period. By content of oils, tars and asphaltes the bitumen under investigation belong to the asphalt type bitumen.

Pupil activities for teaching about water management

2020 ◽  
Author(s):  
Adão Mendes ◽  
João Oliveira
Keyword(s):  
Water Management ◽  
Deionized Water ◽  
The Other ◽  
Chemical Characteristics ◽  
Hot Plate ◽  
Upper Limit ◽  
Life On Earth ◽  
Different Characteristics ◽  
Physical And Chemical ◽  
Glass Beaker

<p>Water is the most necessary natural resource for life on earth, including humans. Of all the water on earth, most is not usable by humans, either because of its physical and chemical characteristics, or because it is difficult to obtain. Examples to aid pupil understanding of different elements of water management include the following.</p><p>1. The differences between dams and salinas<br>Humans try to conserve water, given its importance, both in natural reservoirs and in built reservoirs, as in the example of dams. Dams therefore have different characteristics from salinas where humans try to evaporate water in large quantities. This difference can be demonstrated by dissolving the same amount of salt in two containers in the same amount of deionized water (250 ml) until near saturation. Pour water from one of the containers into a 600 ml glass beaker. Pour water from the other container into a large tray. Mark the upper limit of water in each container with a marker. Put both containers into the oven or warm on a hot plate for 24 hours at 50°C.  The pupils then observe and explain the results in the context of dams and salinas.</p>

scholarly journals Physico-chemical characteristics of passion fruit flour under removal of flavedo and of maceration

2019 ◽  
Vol 23 (11) ◽  
pp. 869-875
Author(s):  
Elaine C. O. da Silva ◽  
Wilton P. da Silva ◽  
Josivanda P. Gomes ◽  
Cleide D. P. da S. e Silva ◽  
Leidjane M. de Souto ◽  
...  
Keyword(s):  
Moisture Content ◽  
Protein Concentration ◽  
Neutral Detergent Fiber ◽  
Passion Fruit ◽  
The Other ◽  
Chemical Characteristics ◽  
Acid Detergent Fiber ◽  
Physico Chemical ◽  
Light Color ◽  
Physical And Chemical

ABSTRACT Passion fruit has the peel (albedo and flavedo) as its major component and it can be used in the production of flour as source of nutrients and enrichment of food products. Thus, this study aimed to evaluate the production of flours from passion fruit albedo and whole peel, verifying the influences of flavedo removal and maceration, as well as the variation in drying temperature (70 and 80 °C) on the physical and chemical characteristics of the flours. The flours has a light color with slight trend to red and stronger trend to yellow. Moisture content is within the limits established by the current norms of ANVISA (a maximum of 15%). The flavedo removal contributed to the increase of water, crude fiber, neutral detergent fiber and acid detergent fiber concentrations. However, it reduced moisture, ash, protein, lipids and carbohydrates concentrations. On the other hand, the maceration decreases luminosity, lipids and carbohydrates and increases the chromaticity a* and b* and moisture in the flours. In relation to the increase in temperature, a decrease was observed in the protein concentration and an increase in the concentration of ash and lipids. Based on centesimal composition, the flour should be prepared with whole peel without maceration and dried at 80 °C.

scholarly journals Characterization of granites by 57Fe Mössbauer spectroscopy

Mineralogia ◽  
2009 ◽  
Vol 40 (1-4) ◽  
pp. 95-106 ◽  
Author(s):  
Kamaledin Hassan
Keyword(s):  
Mössbauer Spectroscopy ◽  
Quadrupole Splitting ◽  
Mossbauer Spectroscopy ◽  
The Other ◽  
Octahedral Coordination ◽  
Mossbauer Spectra ◽  
Mößbauer Spectroscopy ◽  
Other Hand ◽  
Type Granite

Characterization of granites by 57Fe Mössbauer spectroscopyTwo granite complexes in Egypt, a sodic type and an aluminous type are characterized by Mössbauer spectroscopy. Mössbauer spectra (MS) of the sodic granite show a major doublet of ferric (Fe3+) iron that is attributable to octahedral coordination (M1) sites plus/minus a tetrahedron Fe3+ doublet plus/minus a doublet of ferrous (Fe2+) iron on the M1 sites plus/ minus another Fe2+ (M1) doublet and a sextet of Fe3+. The sextet is attributed to α-Fe2O3 (hematite) and the other Fe components are due to NaCaFeSi2O6 (aegirine-augite) plus/minus minor contributions from (Ca2(Mg, Fe)5(Si, Al)8O22(OH)2 (magnesium-hornblende). Changes in the quadrupole splitting and width line of Fe2+ ions are likely composition-related. The MS of the aluminous-type granite, on the other hand, shows evidence only of single doublets containing Fe2+ or Fe3+ in the octahedral M1 sites, with parameters that remain almost constant. This consistency implies that the existing minerals - K(Mg, Fe2+)3 (Al, Fe3+)Si3O10(OH, F)2 (biotite), (Mg, Fe)6(Si, Al)4O10(OH)8 (clinochlore), (Na, K)Ca2(Fe, Mg)5(Al, Si)8O22(OH)2 (ferrohornblende and magnesiohornblende) - have similar iron positions. The intensity of iron oxidized (Fe3+/ΣFe) for the sodic granite is 79.1 to 100% and for the aluminous granite, 28.4 to 38.2%. The observed Fe3+/ΣFe differences between the two granites are source-related and consistent with distributions of other redox-sensitive elements.

scholarly journals Determine The Manufacturing Characteristics of Iraqi Pasterma

2021 ◽  
Vol 910 (1) ◽  
pp. 012056
Author(s):  
Zaid I.H. Zainy ◽  
Amera M.S. Alrubeii
Keyword(s):  
Acetic Acid ◽  
Small Intestine ◽  
Sensory Evaluation ◽  
Storage Period ◽  
Chemical Characteristics ◽  
Drip Loss ◽  
The Third ◽  
Kidney Fat ◽  
Physical And Chemical ◽  
And Storage

Abstract The Study was aimed to determine and fixed the fat source (beef or sheep) and percentages use for production of Iraqi pasterma and to determine the best treatment from them by use measurements of the physical and chemical characteristics and sensory evaluation of the pastrama where stored at a temperature of 4 C0 for a period of 21 days. four treatments were used, the first treatment was used 800 gm of meat with 200 g pelvic and kidney fat, the second treatment used 750 g of meat with 250 g of tail fat, the third treatment used 800 g of meat with 200 grams of tail fat, the fourth treatment used 750 grams of meat with 250 grams of pelvic and kidney fat. with the addition to salt, sugar, spices, then packaged in natural casings (from cleaned cow small intestine sterilized in 15% NaCl with 1% Acetic Acid). Treatments were stored for a storage period of 1,7 14,21 days. to study the effect of treatments and storage periods on properties (pH, WHC, Drip loss, coking loss TBA, moisture protein, fat and ash percentage and sensory evaluation ). The Results was found to be superior to the fourth treatment in the sensory evaluation and have the highest estimate in moisture and lipid measurements and the lowest pH. Results obtaining the best characteristics of fermented pastrami.

Characterization of defects in tabular silver halide grains

1990 ◽  
Vol 48 (4) ◽  
pp. 1046-1047
Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer
Keyword(s):  
Radiation Damage ◽  
Silver Halide ◽  
Chemical Characteristics ◽  
X Ray ◽  
Free Region ◽  
Central Defect ◽  
Crystallographic Defects ◽  
Physical And Chemical ◽  
Two Sides

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.

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