Physicochemical properties as related to mineralogical composition of floodplain soils in humid tropical environment and the pedological significance

2021 ◽  
Vol 193 (9) ◽  
Author(s):  
Maduabuchi E. Ukabiala ◽  
Jonah Kolo ◽  
Sunday E. Obalum ◽  
Sunday O. Amhakhian ◽  
Charles A. Igwe ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Mineralogical Composition ◽  
Tropical Environment ◽  
Floodplain Soils

scholarly journals Physicochemical Properties of Handere Clays and Their Use as a Building Material

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yasin Erdoğan
Keyword(s):  
Physicochemical Properties ◽  
Building Materials ◽  
Raw Materials ◽  
Organic Matter Content ◽  
Volcanic Glass ◽  
Mineralogical Composition ◽  
Matter Content ◽  
Loss On Ignition ◽  
X Ray Diffraction ◽  
Clay Deposits

Handere clay deposits were discovered at Adana in Turkey. These clay units primarily consist of uncoloured claystone, pebbly sandstone, sandstone, siltstone, and mudstone marl and include gypsum lenses and clay levels of various thicknesses in places. The physicochemical properties of these clays have been investigated by different techniques including Scanning Electron and Elemental Analysis (SEM and EDS), mineralogical analyses, chemical and physical analyses, X-ray diffraction (XRD), thermogravimetric differential thermal analysis (TG-DTA), and Atterberg (Consistency) Limits Test. The mineralogical composition deduced from XRD is wide (smectite + palygorskite + illite ± feldspar ± chlorite ± quartz ± calcite ± serpentine) due to the high smectite contents (≈85%). SEM studies reveal that smectite minerals are composed of irregular platy leaves and show honeycomb pattern in the form of wavy leaves in places. The leaves presenting an array with surface edge contact are usually concentrated in the dissolution voids and fractures of volcanic glass. Organic matter content and loss on ignition analysis of raw materials are good for all the studied samples. In summary, Handere clays can be used as building materials in bricks, roof tiles, and cement and as a binder.

Mineralogical and physicochemical characterization of selected Portuguese Mesozoic-Cenozoic muddy/clayey raw materials to be potentially used as healing clays

Clay Minerals ◽  
2010 ◽  
Vol 45 (2) ◽  
pp. 229-240 ◽  
Author(s):  
M. Rebelo ◽  
F. Rocha ◽  
E. Ferreira Da Silva
Keyword(s):  
Physicochemical Properties ◽  
Mineral Water ◽  
Raw Materials ◽  
Physicochemical Characterization ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Water Mixture ◽  
X Ray Diffraction ◽  
Geological Formations

AbstractThe use of pelitic geological materials for the treatment of muscle-bone-skin pathologies, by application of a cataplasm made of clay and mineral water mixture, is currently receiving attention and interest from the general public and scientific community. In Portugal there are several natural occurrences of clays/muds which are used for pelotherapy and/or geotherapy. These are carried out either indoors (thalassotherapy and thermal centres) or outdoors, in natural sites generally located near the seaside. The aim of this study is to assess the mineralogical and physicochemical properties of Portuguese raw materials for therapeutic purposes. These materials were collected from different Portuguese Mesozoic-Cenozoic geological formations located in the neighbourhood of thermal centres or at beaches known from their empirical applications. X-ray diffraction (XRD) and scanning electron microscopy (SEM-EDS) were used to assess the mineralogical composition of these clays. Physicochemical properties, such as specific surface area, cation exchange capacity, plasticity/abrasiveness indices and heat diffusiveness were also determined. Having distinct geological ages and genesis, the materials examined are mainly illitic. Less abundant kaolinite and smectite are also present. With respect to their physicochemical properties, all samples have good thermal properties which make them potentially suitable for therapeutic or aesthetic purposes.

scholarly journals The Potential for Lunar and Martian Regolith Simulants to Sustain Plant Growth: A Multidisciplinary Overview

2022 ◽  
Vol 8 ◽  
Author(s):  
Luigi Giuseppe Duri ◽  
Antonio Giandonato Caporale ◽  
Youssef Rouphael ◽  
Simona Vingiani ◽  
Mario Palladino ◽  
...  
Keyword(s):  
Plant Growth ◽  
Physicochemical Properties ◽  
Life Support ◽  
Dynamic Environment ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Food Sources ◽  
Growth Media ◽  
Martian Regolith

Bioregenerative life support systems (BLSS) are conceived of and developed so as to provide food sources for crewed missions to the Moon or Mars. The in situ resource utilization (ISRU) approach aims to reduce terrestrial input into a BLSS by using native regoliths and recycled organic waste as primary resources. The combination of BLSS and ISRU may allow sustainable food production on Moon and Mars. This task poses several challenges, including the effects of partial gravity, the limited availability of oxygen and water, and the self-sustaining management of resources. Lunar and Martian regoliths are not available on Earth; therefore, space research studies are conducted on regolith simulants that replicate the physicochemical properties of extra-terrestrial regoliths (as assessed in situ by previous missions). This review provides an overview of the physicochemical properties and mineralogical composition of commercially available Lunar and Martian regolith simulants. Subsequently, it describes potential strategies and sustainable practices for creating regolith simulants akin to terrestrial soil, which is a highly dynamic environment where microbiota and humified organic matter interact with the mineral moiety. These strategies include the amendment of simulants with composted organic wastes, which can turn nutrient-poor and alkaline crushed rocks into efficient life-sustaining substrates equipped with enhanced physical, hydraulic, and chemical properties. In this regard, we provide a comprehensive analysis of recent scientific works focusing on the exploitation of regolith simulant-based substrates as plant growth media. The literature discussion helps identify the main critical aspects and future challenges related to sustainable space farming by the in situ use and enhancement of Lunar and Martian resources.

STRUCTURAL CHARACTERIZATION OF A BENTONITE DEPOSIT FROM THE EASTERN IRAN; COMPARISON WITH TWO REFERENCE BENTONITES

2021 ◽  
Vol 16 (1) ◽  
pp. 151-162
Author(s):  
Samira DOLATI ◽  
◽  
Mohsen KALANI
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Mineralogical Composition ◽  
Industrial Applications ◽  
Exchange Capacity ◽  
High Yield ◽  
Fine Grained ◽  
Eastern Iran ◽  
High Fraction

Mineralogically, bentonites are dominated by smectites and due to characteristic textural and physicochemical properties of smectites (e.g. very small particle sizes, high cation exchange capacity) are of a great use in industrial applications. In this study, a bentonite sample was characterized with regard to the particle size distribution, mineralogical composition and cation exchange capacity in comparison with the data for the two internationally well-known bentonites representative for Na- and Ca-bentonites: the Mx-80 bentonite of Wyoming, USA and that of Milos, Greece, respectively. Results show a high fraction of fine-grained particles, which demonstrates high yield of purified clay. Mineralogically, the studied bentonite comprises mainly smectites and expandable illite-smectite mixed layer clay minerals. Main accessory minerals are calcite, silica polymorphs and zeolites. The specific surface area and cation exchange capacity values are 330.3 (m2g-1) and 42.2 (meq/100 g), respectively. It is concluded that the mineralogical, textural and the measured physicochemical properties of the studied bentonite is applicable to the applications in oil industry and its related environment maintenance related issues.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

Applications of SEM/EDXA in cement clinker investigation

1990 ◽  
Vol 48 (4) ◽  
pp. 870-871
Author(s):  
Arezki Tagnit-Hamou ◽  
Shondeep L. Sarkar
Keyword(s):  
Mineralogical Composition ◽  
Physicochemical Characteristics ◽  
Cement Clinker ◽  
Accurate Information ◽  
Phase Identification ◽  
History Of ◽  
Bulk Chemical ◽  
Resolution Imaging ◽  
Proven Method ◽  
Instantaneous Chemical

All the desired properties of cement primarily depend on the physicochemical characteristics of clinker from which the cement is produced. The mineralogical composition of the clinker forms the most important parameter influencing these properties.Optical microscopy provides reasonably accurate information pertaining to the thermal history of the clinker, while XRDA still remains the proven method of phase identification, and bulk chemical composition of the clinker can be readily obtained from XRFA. Nevertheless, all these microanalytical techniques are somewhat limited in their applications, and SEM/EDXA combination fills this gap uniquely by virtue of its high resolution imaging capability and possibility of instantaneous chemical analysis of individual phases.Inhomogeneities and impurities in the raw meal, influence of kiln conditions such as sintering and cooling rate being directly related to the microstructure can be effectively determined by SEM/EDXA. In addition, several physical characteristics of cement, such as rhcology, grindability and hydraulicity also depend on the clinker microstructure.

Studies on the Degradation of Human Fibrinogen by Plasmin and Trypsin

1966 ◽  
Vol 16 (03/04) ◽  
pp. 526-540 ◽  
Author(s):  
E. A Beck ◽  
D. P Jackson
Keyword(s):  
Physicochemical Properties ◽  
Electrophoretic Mobility ◽  
Rapid Loss ◽  
Clotting System ◽  
Human Fibrinogen ◽  
Peptide Bonds ◽  
Physico Chemical ◽  
Starch Gel ◽  
Ph Stat ◽  
Rapid Appearance

SummaryThe effects of trypsin and plasmin on the functional and physicochemical properties of purified human fibrinogen were observed at various stages of proteolysis. Concentrations of plasmin and trypsin that produced fibrinogenolysis at comparable rates as measured in a pH stat produced, at similar rates, loss of precipitability of fibrinogen by heat and ammonium sulphate and alterations in electrophoretic mobility on starch gel. Trypsin produced a more rapid loss of clottability of fibrinogen and a more rapid appearance of inhibitors of the thrombin-fibrinogen clotting system than did plasmin. Consistent differences were noted between the effects of trypsin and plasmin on the immunoelectrophoretic properties of fibrinogen during the early stages of proteolysis.These results are consistent with the hypothesis that trypsin initially reacts with the same peptide bonds of fibrinogen that are split by thrombin, but these same bonds do not appear to be split initially by plasmin. Measurement of the various functional and physico-chemical changes produced by the action of trypsin and plasmin on fibrinogen can be used to recognize various stages of proteolysis.

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