scholarly journals Mineralogical and physico–chemical properties of bentonites from the Jastrabá Formation (Kremnické vrchy Mts., Western Carpathians)

2019 ◽  
Vol 70 (5) ◽  
pp. 433-445 ◽  
Author(s):  
Marek Osacký ◽  
Tomáš Binčík ◽  
Tomáš Paľo ◽  
Peter Uhlík ◽  
Jana Madejová ◽  
...  
Keyword(s):  
Interlayer Space ◽  
Analytical Data ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Mineral Admixtures ◽  
The Past ◽  
Physico Chemical ◽  
The Mean ◽  
Increasing Demand ◽  
Total Specific Surface Area

Abstract In the past years an increasing demand for bentonites resulted in the opening of new bentonite deposits in the Jastrabá Formation. The shortage of information, in particular analytical data, on the bentonites from the newly opened Jastrabá Fm. deposits was the motivation for the current study. Smectite is the predominant mineral in all bulk bentonites from the new deposits. Its amount varied between 43 and 90 wt. %. The bulk bentonites also contain variable amounts (10–57 wt. %) of mineral admixtures such as feldspars, mica, opal-CT, kaolinite, quartz and sometimes goethite. The smectite mineral comprising the studied bentonites was montmorillonite. The octahedral Al in the structure of montmorillonite was partially substituted by Mg, and to a lesser extent by Fe. The interlayer space of montmorillonite is occupied predominantly by divalent exchangeable cations (Ca2+ and Mg2+). The dehydroxylation temperature of smectites (>600 °C) determined on the DTG curves indicates the presence of the cis-vacant variety of montmorillonites. The mean crystallite thicknesses of smectites (TMEAN) calculated by BWA analyses ranges from 7.2 to 11.5 nm. The shape of the crystallite thickness distributions (CTDs) for smectites is lognormal in all cases. Cation exchange capacity (CEC) and total specific surface area (TSSA) increases with increasing amount of smectite. The CEC of 101 meq/100g and TSSA of 616 m2/g correspond to bulk bentonite from the Stará Kremnička III deposit containing 89 wt. % of smectite.

scholarly journals Radiation-induced Grafting of Styrene onto Polyethylene Films for Preparation of Cation Exchange Membranes: Effect of Crosslinking+

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
M. M. Nasef ◽  
H. Saidi ◽  
A. H. Yahaya
Keyword(s):  
Cation Exchange ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Swelling Properties ◽  
Ion Exchange Capacity ◽  
Physico Chemical ◽  
Styrene Divinylbenzene ◽  
Radiation Induced

Crosslinked cation exchange membranes bearing sulfonic acid groups (PE-g-PSSA/DVB) were prepared by radiationinduced grafting of styrene/divinylbenzene (DVB) mixtures onto low density polyethylene (PE) films followed by sulfonation reactions. The effect of addition of DVB (2 and 4%) on the grafting behavior and the physico-chemical properties of the membranes such as ion exchange capacity, swelling and ionic conductivity were evaluated incorrelation with grafting yield (Y%). The structural and thermal properties of the membranes were also studied using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. Crosslinking with DVB was found to considerably affect the properties of the membranes in a way that reduces the swelling properties and enhances the chemical stability. The ion conductivity of the crosslinked membranes recorded a level of 10–2 S/cm at sufficient grafting yield (28%) despite the reduction caused by the formation of crosslinking structure. The results of this work suggest that membranes prepared in this study are potential alternatives for various electrochemical applications.

scholarly journals Correlations between physico-chemical properties and nickel adsorption parameters in soils used in sanitary landfill liners

2020 ◽  
Vol 34 (3) ◽  
pp. 275-284
Author(s):  
Ricardo Antonio Ferreira da Silva ◽  
Danilo Brito da Costa ◽  
William de Paiva ◽  
Márcio Camargo de Melo ◽  
Veruschka Escarião Dessoles Monteiro
Keyword(s):  
Chemical Properties ◽  
Bentonite Clay ◽  
Exchange Capacity ◽  
Isotherm Models ◽  
Sanitary Landfill ◽  
Adsorption Parameters ◽  
Clayey Sand ◽  
Landfill Liners ◽  
Physico Chemical ◽  
Nickel Adsorption

The adsorption of heavy metals by sanitary landfill liners represents a measure of protection of surface and groundwaters against contamination by metals, mitigating risks to public health. Hence, this research aimed to identify, from correlations, the influence of physico-chemical properties of soils applied in landfill liners using nickel adsorption parameters. Batch equilibrium tests with initial nickel concentrations of 45 to 1440 mg.L-1 were performed in clayey sand and bentonite clay soil, as well as in mixtures. Nickel adsorption parameters from Freundlich and Langmuir isotherm models were obtained, exhibiting a better adjustment in the Freundlich model based on R² and RMSE criteria. Thus, the addition of bentonite clay improved the adsorption to nickel, and the cationic exchange capacity (CEC) was the property that considerably influenced the metal retention in the studied soils.

scholarly journals On the cataphoresis of gliadin Part—The adsorption of gliadin on quartz

1934 ◽  
Vol 147 (860) ◽  
pp. 1-10 ◽  
Keyword(s):  
Electric Field ◽  
Chemical Properties ◽  
Plant Proteins ◽  
The Past ◽  
Physico Chemical ◽  
Inert Particles

There have been few systematic investigations of the physico-chemical properties of the more important plant proteins; such investigations as have been carried out in the past have concerned themselves almost entirely with the better known animal proteins. It was, therefore, thought desirable to make a study of the physico-chemical properties of the protein gliadin, which, together with glutenin, forms the chief constituent of the gluten of flour. Of all the methods employed for determining the mobility of colloid ions in an electric field, the micro-cataphoretic method is the most exact. In studying the micro-cataphoresis of protein sols in which the particles are not visible in the ultramicroscope, it has been usual to make measurements using inert particles coated with protein. Although it was found possible to obtain gliadin sols containing visible submicrons, it was decided to make observations also on quartz particles covered with gliadin.

scholarly journals Green waste composting under GORE(R) cover membrane at industrial scale: physico-chemical properties and spectroscopic assessment

2019 ◽  
Vol 8 (S1) ◽  
pp. 385-397 ◽  
Author(s):  
Mutaz Al-Alawi ◽  
Tamas Szegi ◽  
Loubna El Fels ◽  
Mohamed Hafidi ◽  
Barbara Simon ◽  
...  
Keyword(s):  
New Technology ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Ftir Spectra ◽  
Industrial Scale ◽  
Agricultural Product ◽  
Green Waste ◽  
Physico Chemical ◽  
Mature Compost ◽  
Humification Degree

Abstract Purpose Green waste (GW) composting is of increasing importance to the waste management industry in addition being a useful agricultural product that is rich in nutrient and organic matter (OM). The combination of aerated static windrow with GORE(R) cover membrane and an air-floor aeration system is a relatively new industrial-scale composting technology that has not been previously explored. Therefore, the aim of this research study was to evaluate the effectiveness of composting GW using this new technology. Methods The composting process was monitored through changes in the physico-chemical properties, E4/6, and fourier transform infrared (FTIR) spectra. Results Disinfection requirements were met by holding composting temperature steady in the thermophilic range for 24 days. The technology greatly improved composting conditions, and final compost product in terms of temperature, pH, electrical conductivity (EC), C/N ratio, OM degradation, nitrogen transformation, humification, and cation exchange capacity (CEC). The FTIR spectra revealed that there was enrichment of aromatic compounds and reduction in aliphatic structures and easily assimilated peptide components by microorganisms, indicating the humification degree increased, the final compost stabilized, and confirming the efficiency of composting. Consequently, the new technology produced a mature compost in only 30 days compared with the standard period of 90–270 days for traditional composting. Conclusion Notably, the new technology may be a sustainable alternative for GW management that converts waste into compost and could be beneficial for agricultural uses.

scholarly journals Physico-chemical characteristics of the seasonally flooded soils of Bangladesh and their management implications

1970 ◽  
Vol 20 (2) ◽  
pp. 173-182
Author(s):  
KF Akhter ◽  
ZH Khan ◽  
MS Hussain ◽  
AR Mazumder
Keyword(s):  
Organic Matter ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Matter Content ◽  
Flooded Soils ◽  
Management Implications ◽  
Available N ◽  
Physico Chemical ◽  
Seasonally Flooded

The seasonally flooded soils of Bangladesh are unique in respect of several specific characteristics and contribute toward producing bulk of its staple food - mainly rice. Having fine texture these soils are similar to the “paddy soils” of Southeast Asian floodplains and have high production potential under proper management. Six representative soil series, viz. Arial, Debidwar, Naraibag, Jalkundi, Siddirganj and Tippera from the central region of Bangladesh have been studied to evaluate some of their intrinsic physico-chemical properties and their sustainable management requirements. These soils are slightly acidic to neutral and are negatively charged with ΔpH values ranging between –0.2 and –1.2. The organic matter content in the surface soil is relatively low that decreases steadily with depth. The cation exchange capacity (CEC) of the soils varies on the basis of their clay and organic matter contents while base saturation per cent (BSP) is high. The contents of available N, P, K and S and DTPA-extractable Fe, Mn, Cu and Zn in soils are moderate and are commensurate with the contents of colloidal fractions. These soils receive several mineral nutrients annually with the sediments deposited during the monsoon floods. The characteristics like organic matter content, particle size distribution, CEC, pH and BSP that have important management implications have been discussed. Key words: Seasonally flooded soils; Physical and chemical attributes; Management implications DOI: http://dx.doi.org/10.3329/dujbs.v20i2.8978 DUJBS 2011; 20(2): 173-182

scholarly journals Physicochemical Parameters and Heavy Metals Content of Soil Samples from Farms in Minna

2015 ◽  
Vol 58 ◽  
pp. 154-163
Author(s):  
Z. Abdulhamid ◽  
E.B. Agbaji ◽  
C.E. Gimba ◽  
A.S. Agbaji
Keyword(s):  
Heavy Metals ◽  
Cation Exchange Capacity ◽  
Physicochemical Parameters ◽  
Chemical Properties ◽  
Absorption Spectrometry ◽  
Exchange Capacity ◽  
Average Concentration ◽  
Soil Samples ◽  
Ph Values ◽  
Physico Chemical

Physico-chemical properties and heavy metals content of soils were determined from seven farms in Minna, central Nigeria. Conventional analytical methods were employed to determine the physico-chemical properties and the heavy metals were analysed by atomic absorption spectrometry. The result showed that pH values ranged from 6.64 - 7.70 indicating slight acidity to slight alkalinity of the soils. The total organic carbon values ranged from 0.95-2.25 % resulting in the presence of organic matter (1.63-3.87). The electrical conductivity values ranged from 17-37 μS/cm. The cation exchange capacity of the soil samples ranged from 3.68-5.15 cmol/kg. The heavy metals levels were in the following range: Cd (0.00018-0.00134 mg/g), Cu (0.0069-0.0476 mg/g), Fe (1.942-2.2059 mg/g), Mn (0.1825-0.3696 mg/g), Ni (0.0065-0.0069 mg/g) and Zn (0.0157-0.2252 mg/g). The concentration of the metals in the soil samples varied according to the following trend: Fe>Mn>Zn> Cu>Ni>Cd. The average concentration of all the metals in each farm also gave the trend Farm B>Farm G>Farm E>Farm C>Farm F>Farm D>Farm A. The findings indicate the presence of heavy metals in all the farms but only Fe was above the FAO/WHO standards.

scholarly journals Anthropogenic pollution impact on physico-chemical characteristics of Lake Kivu, Rwanda

2012 ◽  
Vol 12 (53) ◽  
pp. 6517-6536
Author(s):  
OJ Olapade ◽  
◽  
BO Omitoyin ◽  
Keyword(s):  
Dissolved Oxygen ◽  
Lake Water ◽  
Chemical Properties ◽  
Oxygen Demand ◽  
Total Dissolved Solids ◽  
Total Alkalinity ◽  
Dissolved Solids ◽  
Physico Chemical ◽  
Lake Kivu ◽  
The Mean

Anthropogenic activities such as industrial effluent, domestic and agricultural waste disposal constitute major sources of pollution in water. The effects of these pollutants on the physico- chemical properties of Lake Kivu, Rwanda were investigated at three locations (Gisenyi, Kibuye and Cyangugu) between February 2005 and December 2006. Water samples used for physico- chemical analysis were collected from 12 stratified points on the lake. Samples collected were analysed and interpreted using appropriate international procedures. The physico -chemical properties measured were temperature, conductivity, pH, transparency, salinity, total alkalinity, dissolved organic matter (DOM), total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), nitrate – nitrogen, phosphate – phosphorus and sulphate. Mean water temperature measured (24.7 + 0.58 o C) was highest in Kibuye and lowest (24.5 + 0.31 o C) in Cyan gugu. The lake water was moderately hard with mean total alkalinity values of 88.1 ± 1.63mgL -1 ; 79.7 ± 2.36mgL -1 and 81.0 ± 2.46mg L -1 recorded in Gisenyi, Kibuye and Cyangugu respectively; salty and alkaline with mean pH values of 8.87 ± 0.07 in Gisenyi; 8.86 ± 0.06 in Kibuye and 8.91 ± 0.06 in Cyangugu. Total dissolved solids (TDS) level in the lake was above the 500mg L -1 prescribed by WHO while the mean biochemical oxygen demand (BOD) reading was within the range for unpolluted or moderately polluted lake. Water from the lake showed mineralization with mean conductivity values ranging from 1058 - 1184μS cm -1 in Gisenyi; 1058 - 1147μS cm -1 in Kibuye and 1031 - 1116μS cm -1 in Cyangugu. The mean dissolved oxygen values were below the 5mgl -1 limit recommended by WHO for fresh water fish species. SO 4- -2 and NO 3 – N concentration in the lake water does not constitute any serious health risk to both man and the aquatic organisms it supports. However, there is the need to constantly monitor the lake water to mitigate any build up of the ions to a hazardous level.

scholarly journals Zoning of a Newly-Planted Vineyard: Spatial Variability of Physico-Chemical Soil Properties

Soil Systems ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 62 ◽  
Author(s):  
José Manuel Mirás-Avalos ◽  
María Fandiño ◽  
Benjamín J. Rey ◽  
Jorge Dafonte ◽  
Javier J. Cancela
Keyword(s):  
Spatial Variability ◽  
Soil Properties ◽  
Low Cost ◽  
Irrigation Management ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Physico Chemical ◽  
Spatio Temporal ◽  
Different Origins ◽  
Two Sectors

Soil properties show a high spatio-temporal variability, affecting productivity and crop quality within a given field. In new vineyard plantations, with changes in the initial topographic profile, this variability is exacerbated due to the incorporation of soil from different origins and qualities. The aim of the current study was to characterize the variability of soil properties in a newly established vineyard, and delineating zones for site-specific management of fertilization. For this purpose, the soil apparent electrical conductivity (ECa) in the first 150 cm was measured with an electromagnetic induction sensor. A soil sampling was performed following a regular grid (35 × 35 m, 149 samples), collecting samples down to 40 cm depth for determining soil chemical properties. Spatial variability was assessed through semivariogram calculation and ordinary kriging. The soil properties that better represent the variability in this newly established vineyard were pH, effective cation exchange capacity (ECEC), carbon content, clay and ECa. The ECa was homogeneous all over the vineyard, except for the area closer to the river where a greater human intervention had occurred, with contributions of external soil at a greater depth. Soil properties showed a great spatial variability. Interpolated maps allowed for detecting areas with a lack of nutrients in which a differential fertilization could be performed in search of a sustainable and balanced production. The information provided by the maps of pH, ECEC and carbon and potassium contents allow for performing a differential management of the vineyard in terms of fertilization. In addition, the results obtained suggest that the vineyard should be divided into two sectors for a differential irrigation management. The ECa was not significantly correlated to most of the soil properties determined in the current study; however, it allowed for a low-cost mapping of the vineyard soil and established large areas of management within the vineyard.

scholarly journals Sensory Profile and Physico-Chemical Properties of Artisanal Honey from Zulia, Venezuela

Foods ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 339 ◽  
Author(s):  
Deyanira Araujo ◽  
Pilar Ruiz Pérez-Cacho ◽  
Salud Serrano ◽  
Rafaela Dios-Palomares ◽  
Hortensia Galán-Soldevilla
Keyword(s):  
Physicochemical Parameters ◽  
Chemical Properties ◽  
Mean Value ◽  
Sensory Profile ◽  
Total Acidity ◽  
Free Acidity ◽  
Chemical Parameters ◽  
Colour Intensity ◽  
Physico Chemical ◽  
The Mean

The physico-chemical parameters and the sensory profile were determined in honeys from apiaries of the Mara and Maracaibo of Zulia State (Venezuela). The analysis of variance showed that there were no significant differences in the mean value between apiaries for most of the physicochemical parameters and sensory attributes. The obtained value for pH (3.58–4.08), free acidity (30.9–36.0 meq/kg), lactone acidity (9.0–14.3 meq/kg), total acidity (42.1–46.0 meq/kg), moisture content (19.1–20.0%), diastase activity (8.11–12.7 ºG), colour intensity (41.5–86.6 mm Pfund), hydroxymethylfurfural (15.7–26.0 mg/kg), and electrical conductivity (0.33–0.52 mS/cm) were within the criteria set by international quality regulations. The sensory profile of these honeys is characterized by being amber in colour, with a floral, acid fruit, balsamic and animal odour/aroma, a sweet, slightly acid taste, and by being fluid and of a medium persistence.

The composition of Alpine goats' milk during lactation in Greece

1990 ◽  
Vol 57 (1) ◽  
pp. 41-51 ◽  
Author(s):  
Leandros Voutsinas ◽  
Christophoros Pappas ◽  
Maria Katsiari
Keyword(s):  
Chemical Composition ◽  
Chemical Properties ◽  
Titratable Acidity ◽  
Average Composition ◽  
Mineral Contents ◽  
Total Solids ◽  
Stage Of Lactation ◽  
Physico Chemical ◽  
The Mean

SummaryVariations in chemical composition and in some physico-chemical properties of milk from a herd of lactating Alpine goats imported into Greece were determined from week 8 after parturition until the end of lactation (35 weeks, 35 samples). The average composition (g/100 g) of the milk was: fat 3·44, protein 3·35, casein 2·46, lactose 4·30, ash 0·79, total solids 11·76 and solids-not-fat 8·32. The average pH was 6·57 and titratable acidity was 16·76 (°D). The averaged density was 1·030. The mean mineral contents (mg/100 g) of the milk were: Na 53·12, K 157·67, Ca 140·06, P 110·00, Mg 13·59, citrate 106·97. All constituents studied as well as pH and density were significantly (P < 0·05) dependent on the stage of lactation. Titratable acidity was not significantly affected by stages of lactation. There were significant (P < 0·001) differences in Na/K and Ca/P ratios in the milk between lactation stages. Trends with lactation for each of the components and physico-chemical properties determined are reported and correlations between constituents in the milk are given.

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