Journal articles: 'Fibrous clay'

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Alcântara, Ana C. S., Margarita Darder, Pilar Aranda, and Eduardo Ruiz-Hitzky. "Polysaccharide–fibrous clay bionanocomposites." Applied Clay Science 96 (July 2014): 2–8. http://dx.doi.org/10.1016/j.clay.2014.02.018.

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Estu Yulianto, Faisal, Fuad Harwadi, and Rusdiansyahi. "Characteristics of Palangkaraya fibrous peat." MATEC Web of Conferences 276 (2019): 05008. http://dx.doi.org/10.1051/matecconf/201927605008.

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Palangkaraya fibrous peat soil is a soil with high organic content and was formed due to decomposition of plants in submerged areas for long periods. In the tropics, peat has a high fiber content that affects the physical and engineering characteristic and have different behavior with clay. Laboratory and field tests were conducted to determine the physical and engineering characteristic of fibrous peat and to compare it with clay. The results of the tests on fibrous peat show peat soil parameter very different from clays. The unit weight of peat is 1.04 gr/cm3 with specific gravity is 1.4 and water content reach 650%. This physical parameter shows that peat is a very soft soil that is dominated by water in its structure. Organic content of peat reached 97% with a very low ash content of 3%. This behavior indicates that the decomposition of plants causes physical properties of peat that are very different from clays. The bearing capacity of the peat is also very low. The shear strength was about 26.8 kPa (ov = 50 kPa) and was dependent on the fiber distribution in the sample under test. Vane shear test results also show the same thing that is 5-7 kPa. The very different behavior of fibrous peat with clay is the consolidation. Peat has 4 stages of compression wherein secondary compression is the main compression. This behavior is due to the fibrous peat has two pores, that are micropores and macropores. The results of comparisons can serve as a basis for determining appropriate peat soil improvement methods.

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TARASENKO, NATALIA, VIKTORIIA PLAVAN, YURII BUDASH, and INNA TKACHENKO. "ДОСЛІДЖЕННЯ СОРБЦІЙНИХ ВЛАСТИВОСТЕЙ ВОЛОКНИСТИХ МАТЕРІАЛІВ, МОДИФІКОВАНИХ ГЛИНИСТИМИ МІНЕРАЛАМИ." Technologies and Engineering, no. 3 (January 4, 2022): 70–78. http://dx.doi.org/10.30857/2786-5371.2021.3.7.

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Abstract. The paper presents the results of determining the sorption properties of nonwoven materials modified with clay minerals, obtained on the basis of fibrous waste, in relation to the methylene blue indicator to determine the possibility of using the created materials in the purification of light industry wastewater from dyes and heavy metal ions.Purpose. Determination of kinetic regularities of sorption (by methylene blue) of fibrous nonwoven materials modified with different types and amounts of clay adsorbents.Methodology. Nonwovens obtained from elastic fibrous waste of the textile industry were used as a basis in the work. They consisted of Lycra 162 C (PU) complex fibers and Nylon 6.6 f20 / 1 (PA-6.6) fibers in a ratio of 70/30 wt. %. For bonding the nonwoven material, adhesive bicomponent fibers Acebon 4/51 black (4 den) (BVCh) (20 wt%) were added to the initial composition. To enhance the sorption capacity of the PU / PA / BV 80/20 fabric, powders of montmorillonite clay (clay grade PBA-18) and palygorskite (clay grade PP-5) type were introduced in an amount of up to 40% by weight of the nonwoven material. Evaluation of the sorption properties of modified fibrous materials with different clay adsorbents was performed by determining the change in the optical density of MS solutions of a given concentration.Scientific novelty. It was found that fibrous materials modified by the studied samples of montmorillonite and paligorskite clays show high absorption capacity relative to the methylene blue dye due to its multilayer sorption. After 24 hours of processing, the degree of absorption is 70% when using clay brand PBA-18 in the amount of 40% by weight of the fibrous material, which is higher than when using clay brand PP-5 (45%) under the same conditions.Practical value. Sorption materials modified with clay minerals can be further used to treat wastewater from light and chemical industries from heavy metal ions.

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Hurst, A. "Textural and geochemical micro-analysis in the interpretation of clay mineral characteristics: lessons from sandstone hydrocarbon reservoirs." Clay Minerals 34, no. 1 (March 1999): 137–49. http://dx.doi.org/10.1180/000985599545993.

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AbstractBack-scattered electron images of clay minerals from sandstones are used, together with complementary micro-analytical methods, to identify and quantify mineral microporosity and geochemistry. Clay minerals typically have a range of microporosity from 10 to >90% dependent on texture and paragenesis. Fibrous clays are highly microporous; detrital clays have low microporosity but specific clay minerals have broad ranges of microporosity. The often quoted mineral-chemical association between thorium (Th) and kaolinite cannot be substantiated by micro-analysis. The Th content of clay minerals is associated with micro-inclusions within the kaolinite which form diagenetically or are derived from precursor minerals.

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Cruz Magalhães, Xavier Katiane, Santos Maria do Socorro Ferreira, Maria Rita de Morais Chaves Santos, Luz Adão Benvindo, Brasileiro Luzana Leite, Carvalho Maria Wilma Nunes Cordeiro, and Edson Cavalcanti Silva Filho. "Thermal Activation of Palygorskite at Different Temperatures." Materials Science Forum 775-776 (January 2014): 47–51. http://dx.doi.org/10.4028/www.scientific.net/msf.775-776.47.

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The palygorskite or attapulgite is a mineral clay that has a fibrous morphology with porous crystalline structure, hydrated of type 2:1, which is constituted by layer-shaped strips with two tetrahedral layers connected by a central octahedral layer through the sharing of common oxygens [. It presents in its structure low surface charge, high magnesium content and high specific surface area. This mineral clay together with the sepiolite belong to the class of fibrous clay minerals [.

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., Naoto Yoshida, Tadahumi Naka ., and Kazuyoshi Ohta . "Mutagenesis of Bacteria by Fibrous or Clay Minerals." Journal of Biological Sciences 4, no. 4 (June 15, 2004): 532–36. http://dx.doi.org/10.3923/jbs.2004.532.536.

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Pozo, Manuel, and José Calvo. "An Overview of Authigenic Magnesian Clays." Minerals 8, no. 11 (November 9, 2018): 520. http://dx.doi.org/10.3390/min8110520.

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Clay authigenesis mostly concerns: (a) the formation of clays by direct precipitation from solution, called “neoformation” and (b) development of clays by transformation of precursor minerals. Precipitation from solution implies that a new mineral structure crystallizes, so that a prior mineral structure is not inherited. Transformation of precursor detrital minerals, a process also termed “neoformation by addition”, can be conducted whether throughout precipitation on pre-existing natural surfaces or transformation and reaction on pre-existing surfaces. Both processes have been recognized as effective mechanisms in the formation of Mg-clays, which mostly include 2:1 clay minerals, such as talc-kerolite and Mg-smectites, as well as fibrous clays (sepiolite, palygorskite). Authigenic Mg-clay minerals occur in both modern and ancient marine and non-marine depositional environments, although formation of these clays in hydrothermal continental and seafloor settings must be also outlined. Most favourable conditions for the formation of Mg-clays on earth surface are found in evaporitic depositional environments, especially where parent rocks are enriched in ferromagnesian minerals. In these settings, Mg-clays are important constituent of weathering profiles and soils and can form thick deposits of significant economic interest. Based on this review of authigenic clay deposits, we propose three geochemical pathways, mainly related to continental environments, for the origin of authigenic Mg-clays: formation of Al-bearing Mg-clays (pathway 1), formation of Al-free Mg clays (pathway 2) and formation of sepiolite from other Mg-clay minerals (pathway 3).

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Helios-Rybicka, E. "Sorption of Ni, Zn and Cd on Sepiolite." Clay Minerals 20, no. 4 (December 1985): 525–27. http://dx.doi.org/10.1180/claymin.1985.020.4.09.

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The ability of clay minerals to adsorb heavy metal cations is an important property in the context of the increasing contamination of the aquatic environment and soils by toxic waste. Laboratory studies of the sorption of heavy metals by clays have mostly been carried out using montmorillonite and illite (Chester, 1965; Egozy, 1970; Bourg & Filby, 1974; Helios-Rybicka & Schoer, 1982), less frequently for kaolinite, and only rarely for mixed-layer illite-montmorillonite (Helios-Rybicka, 1983) and the fibrous clay minerals sepiolite and palygorskite. This note describes the sorptive behaviour of sepiolite towards Ni, Zn and Cd.

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Miranda, Maicon Oliveira, Francisca Pereira de Araújo, Josy Anteveli Osajima, and Edson Cavalcanti Silva Filho. "Incorporation of Zirconium Oxide on the Surface of Palygorskite Clay for Photodegradation of Industrial Dye." Materials Science Forum 869 (August 2016): 768–72. http://dx.doi.org/10.4028/www.scientific.net/msf.869.768.

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The palygorskite or attapulgite is a mineral clay of fibrous habits, a phyllosilicate 2:1, presented by the formula Mg5[Si8O20](OH)2(OH2)4.4H2O. Taking advantage of this natural resource available in the State of Piauí, this research aims at incorporating the zirconium oxide to the surface of this clay, through the sol-gel method, in order to evaluate the photoactivity of the composite. The material was characterized by the X-ray diffractometry (XRD), indicating the presence of the zirconium oxide, with the emergence of peaks in 30.8° and 60.9°. It was observed the incorporation of zirconium on the clay by transmission electron microscopy (TEM) and verified the fibrous habit and the presence of ZrO2 on the surface of the clay with 1.35% of incorporated zirconium and 127.4 m2 g-1. The rate of degradation of the Remazol Blue dye was 93.5% when using the composite.

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La Noce, Michele, Alessandro Lo Faro, and Gaetano Sciuto. "Clay-Based Products Sustainable Development: Some Applications." Sustainability 13, no. 3 (January 28, 2021): 1364. http://dx.doi.org/10.3390/su13031364.

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Clay has a low environmental impact and can develop into many different products. The research presents two different case studies. In the first, the clay is the binder of raw earth doughs in order to produce clay-bricks. We investigate the effects of natural fibrous reinforcements (rice straws and basalt fibers) in four different mixtures. From the comparison with a mix without reinforcements, it is possible to affirm that the 0.40% of basalt fibers reduce the shrinkage by about 25% and increase the compressive strength by about 30%. Future studies will focus on identifying the fibrous effects on tensile strength and elastic modulus, as well as the optimal percentage of fibers. In the second study, the clay, in form of brick powder (“cocciopesto”), gives high alkaline resistance and breathability performance, as well as rendering and color to the plaster. The latter does not have artificial additives. The plaster respects the cultural instance of the original building. The research underlines how the use of a local (and traditional) material such as clay can be a promoter of sustainability in the contemporary building sector. Future studies must investigate further possible uses of clay as well as a proper regulatory framework.

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Plavan, Viktoriia, Natalia Tarasenko, Tatiana Dutchin, and Yurii Budash. "REGULATION OF SORPTION CAPACITY OF COMBINED FIBER MATERIALS FILLED WITH CLAY MINERALS." Technical Sciences and Technologies, no. 4(26) (2021): 113–20. http://dx.doi.org/10.25140/2411-5363-2021-4(26)-113-120.

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The results of determining the sorption properties of samples of combined fibrous materials impregnated with dispersions of water-soluble polymers of different types and concentrations filled with clay minerals in relation to the methylene blue dye are presented. The rational composition of dispersions of water-soluble polymers filled with clay minerals is determined. The obtained materials can be used as a reinforcing base of fibrous sorbents for their further use in the treatment of light industry wastewater from dyes and heavy metal ions.The aim of the work is to determine the kinetic regularities of sorption (by methylene blue) of combined fibrous materials impregnated with dispersions of water-soluble polymers of different types and concentrations filled with clay minerals. As a fibrous basis for the composite material used knitted fabric with a surface density of 240 g/m2, which was made of plaited weave using cotton yarn with a linear density of 25 Tex and polyethylene complex threads with a linear density of 16.5 Tex on a single-font circular knitting machine type MS. First, a dispersion of the clay mineral was prepared in an aqueous solution of a polymeric binder, which was then applied with a squeegee knife to the surface of the knitted material. The sorption properties of the samples were determined by the methylene blue dye, the change in optical density was measured on a UNICO 2150 E spectrophotometer, wavelength 600 nm, cuvette 10 mm. Calculated the degree of absorption of the dye from the solution after 24, 48 and 72 hours of treatment. It was determined that increasing the duration of sorption above 48 hours is not rational. The highest degree of absorption of MS is shown by samples of knitted material treated with 3% dispersions of PVA and starch,78.4 and 77.1%, respectively. This is probably due to the fact that these samples are characterized by the highest content of clay adsorbent, the weight gain for these samples after the introduction of clay adsorbent was 78.7 and 60.1%, respectively. In the case of the use of filled dispersions of CMC and CMS, a larger amount of clay adsorbent is characterized by samples treated with dispersions of CMC and CMC of lower concentration.

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Ndolo, P. J., and E. G. Rhoden. "SWEET POTATO GROWTH AND ROOT DEVELOPMENT IN FRITTED CLAY MEDIA." HortScience 25, no. 8 (August 1990): 855F—855. http://dx.doi.org/10.21273/hortsci.25.8.855.

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Root growth of sweet potato [Ipomoea batatas (L) Lam.] cvs `TI-82-155', `Centennial' and `Rojo Blanco' in coarse fritted clay soil, was investigated under greenhouse conditions. The sweet potato cultivars were harvested at 41 and 82 days after planting. Dry weight of fibrous roots of all cultivars were similar at day 41. Fibrous root weight of `Rojo Blanco' increased by 5% while those of the other cultivars increased by 168%. Mean fibrous root length per centimeter depth was not significantly different among cultivars. Although fresh weight of storage roots of `Rojo Blanco' was significantly lower than those of the other cultivars, their dry weights were similar. `TI-82-155' and `Rojo Blanco' had fewer storage roots compared to the other cultivars, however, storage root length of `TI-82-155' or `Rojo Blanco' was greater than that of `Georgia Jet' or `Centennial'. Length to diameter ratio of the storage root of `Rojo Blanco' was significantly greater than that of `TI-82-155' and `Georgia Jet'.

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Ndolo, P. J., and E. G. Rhoden. "SWEET POTATO GROWTH AND ROOT DEVELOPMENT IN FRITTED CLAY MEDIA." HortScience 25, no. 8 (August 1990): 855f—855. http://dx.doi.org/10.21273/hortsci.25.8.855f.

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Root growth of sweet potato [Ipomoea batatas (L) Lam.] cvs `TI-82-155', `Centennial' and `Rojo Blanco' in coarse fritted clay soil, was investigated under greenhouse conditions. The sweet potato cultivars were harvested at 41 and 82 days after planting. Dry weight of fibrous roots of all cultivars were similar at day 41. Fibrous root weight of `Rojo Blanco' increased by 5% while those of the other cultivars increased by 168%. Mean fibrous root length per centimeter depth was not significantly different among cultivars. Although fresh weight of storage roots of `Rojo Blanco' was significantly lower than those of the other cultivars, their dry weights were similar. `TI-82-155' and `Rojo Blanco' had fewer storage roots compared to the other cultivars, however, storage root length of `TI-82-155' or `Rojo Blanco' was greater than that of `Georgia Jet' or `Centennial'. Length to diameter ratio of the storage root of `Rojo Blanco' was significantly greater than that of `TI-82-155' and `Georgia Jet'.

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Wu, Qingfeng, Kristen Carlson, Qi Cheng, Xisen Wang, and Zhaohui Li. "Interactions between Cationic Dye Toluidine Blue and Fibrous Clay Minerals." Crystals 11, no. 6 (June 20, 2021): 708. http://dx.doi.org/10.3390/cryst11060708.

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Interactions between cationic dyes and negatively charged mineral surfaces have long attracted great attention from clay mineralogists, environmental scientists, and chemical engineers. In this study, the interactions between a cationic dye toluidine blue (TB) and palygorskite and sepiolite were investigated under different experimental conditions. The results showed that in addition to cation exchange, the specific surface area (SSA) of the minerals, particularly the formation of dimer molecules on the surface of both minerals, also accounted for the much higher TB uptake in comparison to their cation exchange capacities (CEC). The TB molecules were sorbed to the external surfaces, as no d-spacing expansion was observed in X-ray diffraction analyses. FTIR analyses showed strong interactions between the C=N or N-(CH3)2 group and the mineral surfaces, suggesting net electrostatic interactions if either of these functional groups bears a positive charge. Results from molecular dynamic simulations suggested dense monolayer TB formation on palygorskite because of its limited SSA and large CEC values. In comparison, a loosely dimeric formation was revealed on sepiolite for its large SSA and limited CEC values. Therefore, palygorskite is a better carrier for the sorption of cationic dyes, as evidenced by Maya blue paintings.

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Perderiset, M., L. Saint Etienne, J. Bignon, and M. C. Jaurand. "Interactions of attapulgite (fibrous clay) with human red blood cells." Toxicology Letters 47, no. 3 (June 1989): 303–9. http://dx.doi.org/10.1016/0378-4274(89)90149-5.

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Ruiz-Hitzky, Eduardo, Pilar Aranda, Marwa Akkari, Nithima Khaorapapong, and Makoto Ogawa. "Photoactive nanoarchitectures based on clays incorporating TiO2 and ZnO nanoparticles." Beilstein Journal of Nanotechnology 10 (May 31, 2019): 1140–56. http://dx.doi.org/10.3762/bjnano.10.114.

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Thought as raw materials clay minerals are often disregarded in the development of advanced materials. However, clays of natural and synthetic origin constitute excellent platforms for developing nanostructured functional materials for numerous applications. They can be easily assembled to diverse types of nanoparticles provided with magnetic, electronic, photoactive or bioactive properties, allowing to overcome drawbacks of other types of substrates in the design of functional nanoarchitectures. Within this scope, clays can be of special relevance in the production of photoactive materials as they offer an advantageous way for the stabilization and immobilization of diverse metal-oxide nanoparticles. The controlled assembly under mild conditions of titanium dioxide and zinc oxide nanoparticles with clay minerals to give diverse clay–semiconductor nanoarchitectures are summarized and critically discussed in this review article. The possibility to use clay minerals as starting components showing different morphologies, such as layered, fibrous, or tubular morphologies, to immobilize these types of nanoparticles mainly plays a role in i) the control of their size and size distribution on the solid surface, ii) the mitigation or suppression of the nanoparticle aggregation, and iii) the hierarchical design for selectivity enhancements in the catalytic transformation and for improved overall reaction efficiency. This article tries also to present new steps towards more sophisticated but efficient and highly selective functional nanoarchitectures incorporating photosensitizer elements for tuning the semiconductor–clay photoactivity.

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HAJJAJI, M., A. ALAMI, and A. BOUADILI. "Removal of methylene blue from aqueous solution by fibrous clay minerals." Journal of Hazardous Materials 135, no. 1-3 (July 31, 2006): 188–92. http://dx.doi.org/10.1016/j.jhazmat.2005.11.048.

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Siddikov, M. "Research of the Structure and Physical-Mechanical Properties of Modified Clay." Bulletin of Science and Practice 7, no. 12 (December 15, 2021): 185–91. http://dx.doi.org/10.33619/2414-2948/73/25.

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The article presents the properties of natural clay in Uzbekistan. The historical analysis of the use of this natural raw material is presented. Possibilities of changing the properties of clay by introducing synthetic fibers of light industry waste into it are considered. Calculations of the properties of clay with the introduction of various additives and the technology of its processing are given. It has been established that modification of clay with fibrous waste and subsequent heat treatment improves frost resistance, and water resistance of the material, these properties depend on the percentage of fiber content, heat treatment temperature and time of holding the material in the furnace.

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Lopez-Aguayo, F., and J. M. Gonzalez Lopez. "Fibrous clays in the Almazan Basin (Iberian Range, Spain): genetic pattern in a calcareous lacustrine environment." Clay Minerals 30, no. 4 (December 1995): 395–406. http://dx.doi.org/10.1180/claymin.1995.030.4.11.

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AbstractThe Tertiary sediments of the southern part of Almazán basin (Province of Soria) exhibit two different facies with a sharp transition between them: (1) a coarse detrital facies; and (2) a lutite and carbonate facies. The vertical evolution of these facies in the different sections and boreholes is made up of several retrograde depositional sequences which evolve from proximal alluvial fans to carbonate lacustrine systems associated with the most distal fan sediments.The variation of the mineralogical association (carbonates, quartz, detrital clay minerals, palygorskite and, occasionally, sepiolite and smectites) allows four ‘mineralogical facies’ to be established. Each facies has a distinctive mineralogy related to the main genetic processes: (1) detrital facies; (2) transitional facies; (3) ‘chemical dolomite-palygorskite’ facies and (4) ‘chemical calcite’ facies. Although the carbonates (calcite and dolomite) are always the most abundant minerals, fibrous clay minerals are also important. The main mechanism of mineral authigenesis in this basin is chemical precipitation; the presence and distribution of carbonates and fibrous clay minerals is controlled by the relative concentrations of [Mg2+], [Ca2+], pCO2, pH and [SiO4H4]. Palygorskite occurrences, in these conditions, are related to dissolution-precipitation mechanisms of pre-existing detrital material.

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Rhoden, E. G., P. J. Ndolo, and G. W. Carver. "RELATIONSHIP BETWEEN SWEETPOTATO FIBROUS ROOT GROWTH AND NUTRIENT UPTAKE IN FRITTED CLAY MEDIA." HortScience 26, no. 5 (May 1991): 494a—494. http://dx.doi.org/10.21273/hortsci.26.5.494a.

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A greenhouse study was conducted to investigate the ability of sweetpotato (Ipomoea batatas), cv. `Centennial', `Rojo Blanco', `Georgia Jet' and `TI-82-155', fibrous roots to accumulate N, P, K, Ca and Mg. Sweetpotato plants were grown in a fritted clay medium and harvested 42 and 82 days after planting. Fibrous roots comprised 22 to 28.1% and 3.9 to 11.1% of the plant dry weight at 42 and 82 days after planting, respectively. There was no difference in the average root length/cm depth of soil among the four sweetpotato cultivars at day 42. While there was no difference in average root length among `Centennial', `Rojo Blanco' and `TI-82-155', these cultivars were significantly different from `Georgia Jet' at day 82. For the four cultivars, there were no significant differences in N, P, K, Mg and Ca Uptake at day 42, but each cultivar absorbed significantly more of each element 82 days after planting. `Georgia Jet' absorbed significantly more of the nutrients measured than the other cultivars, resulting in the highest dry matter yield. The data show that the efficient uptake and utilization of nutrients by sweetpotato are related to the amount of fibrous roots present.

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Silva, Marcos Pereira, Marília Evelyn Rodrigues Oliveira, Francisco Marcos Costa Batista, Maria Rita de Morais Chaves Santos, Maria Gardennia Fonseca, and Edson Cavalcanti Silva Filho. "Organofunctionalization of Natural Palygorskite with Ethylene Sulfide in the Absence of a Solvent." Materials Science Forum 869 (August 2016): 176–80. http://dx.doi.org/10.4028/www.scientific.net/msf.869.176.

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The search for functional materials has increased daily in order to improve their functionality while maintaining a low cost. Among the materials of considerable interest are clays and within them is a particular clay known as palygorskite, which contains a hydrated silicate of aluminum and magnesium with a fibrous morphology. This work achieved the organofunctionalization of palygorskite with ethylene sulfide in the absence of a solvent. Through the elemental analysis of sulphur, the incorporation of 9.73 ± 0.36 mmol g-1 was identified. A significant decrease in the crystallographic planes (110) and (040) was identified in the XRD. The FTIR showed vibrations of stretching and deformation of the methylene groups in the region below 3000 and in 1421 cm-1, respectively. The deformation related to the C-S group in the region of 700 and 600 cm-1, and the surface area (BET) showed a significant reduction from 113 to 7 m2 g-1. Additionally, the SEM presented a loss of fibrous character.

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Benobeidallah, B., A. Benhamida, A. Dorigato, A. Sola, M. Messori, and A. Pegoretti. "Structure and Properties of Polyamide 11 Nanocomposites Filled with Fibrous Palygorskite Clay." Journal of Renewable Materials 7, no. 1 (2019): 89–102. http://dx.doi.org/10.32604/jrm.2019.00136.

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Cecilia, J. A., E. Vilarrasa-García, C. L. Cavalcante, D. C. S. Azevedo, F. Franco, and E. Rodríguez-Castellón. "Evaluation of two fibrous clay minerals (sepiolite and palygorskite) for CO2 Capture." Journal of Environmental Chemical Engineering 6, no. 4 (August 2018): 4573–87. http://dx.doi.org/10.1016/j.jece.2018.07.001.

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Tobilko, Victoria, Larysa Spasonova, Iryna Kovalchuk, Borys Kornilovych, and Yurij Kholodko. "Adsorption of Uranium (VI) from Aqueous Solutions by Amino-functionalized Clay Minerals." Colloids and Interfaces 3, no. 1 (March 23, 2019): 41. http://dx.doi.org/10.3390/colloids3010041.

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Silylation of clay minerals from Cherkasy deposit (Ukraine) montmorillonite (layer silicate) and palygorskite (fibrous silicate) was performed using organosilane (3-aminopropyl)triethoxysilane (APTES). Solvents with different polarity (ethanol, toluene) were used in synthesis. The structure of modified minerals was characterized by complex of methods (X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption at −196 °C and thermal analysis). Studies of adsorption characteristics of APTES-modified clay minerals were carried out in relation to uranium (VI). The results indicated that modified montmorillonite and palygorskite were effective materials for water purification from UO22+.

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Sieren, Ben, Jessica Baker, Xisen Wang, Samuel J. Rozzoni, Kristen Carlson, Alyssa McBain, Daniel Kerstan, Lori Allen, Libing Liao, and Zhaohui Li. "Sorptive Removal of Color Dye Safranin O by Fibrous Clay Minerals and Zeolites." Advances in Materials Science and Engineering 2020 (December 2, 2020): 1–12. http://dx.doi.org/10.1155/2020/8845366.

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The increased use of color dyes in industry imposes a great threat to the environment. As such, developing cost-effective techniques for dye removal from wastewater attracted great attention. Earth materials, particularly those with large specific surface area (SSA) and high cation exchange capacity (CEC), were evaluated for their potential use for wastewater treatment. In this study, palygorskite, sepiolite, and clinoptilolite were evaluated for their removal of cationic dyes using safranin O (SO+) as a model compound. The CEC values of the materials played a key role in SO+ removal while other physicochemical conditions, such as temperature, equilibrium solution pH, and ionic strength, had less influence on SO+ removal. Sorbed SO+ cations were limited to the external surfaces of the minerals, as their channel sizes are less than the size of SO+ cation. Molecular dynamic simulations showed dense monolayer SO+ uptake on palygorskite due to its relatively large CEC value. In contrast, loosely packed monomer SO+ uptake was adopted on sepiolite for its large SSA and low CEC. Dense multilayers or admicelles of SO+ formed on zeolite surfaces. As such, for the best SO removal, palygorskite is better than sepiolite, though both are fibrous clay minerals.

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Singer, Arieh, Willem Kirsten, and Christel Bühmann. "Fibrous clay minerals in the soils of Namaqualand, South Africa: characteristics and formation." Geoderma 66, no. 1-2 (April 1995): 43–70. http://dx.doi.org/10.1016/0016-7061(94)00052-c.

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Bouza, P. J., M. Simón, J. Aguilar, H. del Valle, and M. Rostagno. "Fibrous-clay mineral formation and soil evolution in Aridisols of northeastern Patagonia, Argentina." Geoderma 139, no. 1-2 (April 2007): 38–50. http://dx.doi.org/10.1016/j.geoderma.2007.01.001.

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Plaček Otcovská, Tereza, Barbora Mužíková, and Pavel Padevět. "MECHANICAL PROPERTIES OF RAMMED EARTH WITH RESPECT TO CLAY MIXTURE COMPOSITION." Acta Polytechnica 59, no. 4 (August 31, 2019): 372–83. http://dx.doi.org/10.14311/ap.2019.59.0372.

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Unfired earth is a traditional building material, but it is less used than other building materials, such as concrete or steel. But the use of unfired earth is experiencing a renaissance. ammed earth is a type of unfired earth and is usually used for load bearing structures. This paper descries an experimental determination of the tensile bending strength and compressive strength of the rammed earth specimens with known compositions. Mechanical properties are dependent on these compositions (kind of clay, amount of clay, amount of mixture water). Laboratory specimens were produced without inorganic binders or fibrous admixtures. We observed higher tensile bending strengths and lower compressive strengths in specimen mixtures containing more clay. The obtained results were evaluated in a context of a previous research. The results were also compared with results published by another author.

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Shcherban, Evgeniy M., Albert Yu Prokopov, Sergey A. Stelmakh, and Anatoliy I. Shuyskiy. "Effect of Disperse Reinforcement on the Structural Quality Factor of Vibrated and Centrifuged Concretes on the Сombined Aggregate." Materials Science Forum 974 (December 2019): 283–87. http://dx.doi.org/10.4028/www.scientific.net/msf.974.283.

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The article considers and evaluates the impact of dispersed reinforcement of vibrated and centrifuged concretes manufactured with various types of fibers on their strength-density ratio. The authors considered the application of such a recipe manufacturing method as combining aggregates by the example of heavyweight aggregate - crushed stone and light aggregate - expanded clay aggregate for these concretes. Registered strength-density ratio of centrifuged fibrous concretes with a combined aggregate is higher than vibrated concretes with the same composition of the studied fibers. The highest growth of the strength-density ratio for the centrifuged fibrous concretes as compared with the vibrated ones was identified in case of dispersed reinforcement with steel fiber.

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Qiu, Zhi-Cheng, Jing-Jing Zhang, Cai-Li Huang, Ying Niu, Ke-Ke Yang, and Yu-Zhong Wang. "The influence of the surface character of the clays on the properties of poly(p-dioxanone)/fibrous clay nanocomposites." Journal of Applied Polymer Science 125, S1 (January 12, 2012): E247—E259. http://dx.doi.org/10.1002/app.35040.

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Hong, H. L., N. Yu, P. Xiao, Y. H. Zhu, K. X. Zhang, and S. Y. Xiang. "Authigenic palygorskite in Miocene sediments in Linxia basin, Gansu, northwestern China." Clay Minerals 42, no. 1 (March 2007): 45–58. http://dx.doi.org/10.1180/claymin.2007.042.1.04.

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AbstractThe mineralogical characteristics of authigenic palygorskite occurring with chlorite and illite in Miocene sediments in Linxia basin were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). The XRD results suggest that the mineral composition of the sediments includes mainly quartz, chlorite, illite, calcite, plagioclase, orthoclase, minor palygorskite and small amounts of gypsum and ankerite. Two kinds of palygorskite were observed in the sediments, relatively straight fibrous particles found in matted, felted masses associated with platy chlorite and silky aggregates found in the void spaces. The former probably replaces chlorite grains, growing from the edges or the fissures of chlorite particles. Chlorite grains exhibit bay-shaped or rounded edges, with ambiguous felted boundaries between chlorite particles, indicative of an intensive dissolution process and the growth of palygorskite at the expense of chlorite. Palygorskite is also observed as inclusions within calcite, sprouting from or coating calcite surfaces, suggesting that palygorskite crystallized from solution. The textural relations of palygorskite and the occurrence of ankerite and the characteristically Fe-bearing palygorskite in the sediments suggest the destruction and hydrolysis of chlorite. The ankerite seems to be preferentially present in the void spaces, closely associated with chlorite and illite; fibrous palygorskite crystallizes at the edges of these clay mineral particles and the platy clay mineral particles are gradually replaced by fibrous palygorskite crystals, suggesting that alteration of chlorite to palygorskite involves an interaction with water during the diagenetic process.

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Filippidis, Anestis, Christina Mytiglaki, Nikolaos Kantiranis, and Ananias Tsirambides. "The Mineralogical Composition of Samos Zeoliitic Rocks and their potential use as Feed Additives and Nutrition Supplements." Bulletin of the Geological Society of Greece 56, no. 1 (April 6, 2020): 84. http://dx.doi.org/10.12681/bgsg.20706.

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Fifteen (15) zeolitic rocks from Karlovassi-Marathokampos basin of Samos Island (Greece) were investigated for their mineralogical composition by X-Ray Diffraction (XRD) method. According to EU Regulation No 651/2013, clinoptilolite of sedimentary origin with ≥80 wt% clinoptilolite, ≤20 wt% clay minerals, free of fibres and quartz, can be used as feed additive for all animal species. Depending on the zeolites, the zeolitic rocks are grouped to those containing: Clinoptilolite (33-86 wt%), clinoptilolite (59 wt%) + mordenite (20-21 wt%), clinoptilolite (22 wt%) + analcime (29 wt%), clinoptilolite (17 wt%) + phillipsite (27 wt%), analcime (29-70 wt%), mordenite (62%) and chabazite (63 wt%). None of the clinoptilolite-containing rocks (10 samples) meet the requirements of the EU Regulation No 651/2013, and thus cannot be used as feed additives for all animal species and consequently as nutrition supplements, since all of them contain 2-5 wt% quartz, two of them 20-21 wt% mordenite (fibrous zeolite), nine of them <80 wt% clinoptilolite (17-73 wt%) and two of them >20 wt% clay minerals (27-42 wt%). Although the EU Regulation No 651/2013 refers to clinoptilolite of sedimentary origin, using the presence or absence of quartz and fibrous minerals, none of the five mordenite, analcime and chabazite containing zeolitic rocks, can be used as feed additives and nutrition supplements, since all of them contain 2-6 wt% quartz and one of them contains 62 wt% mordenite (fibrous zeolite).

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Silva, Josany Saibrosa da, Ana Cristina Sousa Gramoza Vilarinho, Hernane da Silva Barud, Edson Cavalcanti da Silva Filho, and Livio Cesar Cunha Nunes. "Utilização de argilas fibrosas e tubulares para a liberação modificadas de fármacos: uma revisão." Matéria (Rio de Janeiro) 21, no. 1 (March 2016): 204–12. http://dx.doi.org/10.1590/s1517-707620160001.0018.

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Nas últimas décadas o uso de argilominerais nas áreas de Ciência e Engenharia de Materiais tem recebido notória atenção para a sua utilização no carreamento de fármacos. Dentre os diversos tipos de argilas, as fibrosas e as tubulares tem sido utilizadas na preparação de bionanocompósitos, devido as suas propriedades inerentes, como exemplo a elevada área superficial. Esta pesquisa visou o levantamento bibliográfico da utilização das argilas tubulares e fibrosas para o carreamento de fármacos. A busca por artigos foi realizado no banco de dados Web of Science, utilizando combinação dos termos: Fibrous Clay and drug delivery, Tubular Clay and drug delivery, Halloysite and drug delivery, Imogolite and drug delivery, Palygoskite and drug delivery e Sepiolite and drug delivery. Foram encontrados o total de 36 artigos durante a pesquisa. Observou-se que a maioria dos artigos utilizam as argilas em combinação com outros materiais (com formação de compósitos e blendas), principalmente polímeros, a fim de expandir as propriedades que melhoram a vetorização de insumos farmacêuticos ativos (IFAs), tais como a modificação do tamanho dos poros, do pH, da energia de ligação entre as moléculas, entre outros. Assim, evidencia-se que o interesse pela utilização das argilas no campo terapêutico tem aumentado, mostrando a relevância de pesquisas na área de medicamentos e materiais.

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Letaief, Sadok, Yun Liu, and Christian Detellier. "Zirconium oxide nanoparticles coated on sepiolite by sol–gel process — Their application as a solvent-free catalyst for condensation reactions." Canadian Journal of Chemistry 89, no. 3 (February 2011): 280–88. http://dx.doi.org/10.1139/v10-142.

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An inorganic nanocomposite made of zirconia nanoparticles coated on the external surfaces of the fibrous clay mineral sepiolite was prepared by using the sol–gel process under soft conditions using zirconium(IV) propoxide in 1-propanol as the precursor. The resulting materials were characterized by X-ray diffraction (XRD), thermal gravimetric analyses (TGA) and differential thermal analyses (DTA), microporosimetry, 29Si magic-angle spinning (MAS) nuclear magnetic resonance (NMR), and high-resolution transmission electron microscopy (HR-TEM). The organic material from the precursor was fully removed after calcination at 450 °C, concurrently with the crystallization of the cubic phase of zirconium oxide. The coordinated water molecules of sepiolite were fully removed and its symmetrical layered structure was folded after calcination at 650 °C, as observed by XRD and 29Si cross-polarization (CP) / MAS NMR. The arrangement of the nanoparticles of zirconium oxide on the sepiolite external surfaces maintains a fibrous morphology for the nanocomposite. This material was applied as a catalyst for the Knoevenagel condensation reaction of benzaldehyde and malononitrile under solvent-free conditions. Strongly improved yields of reaction, attributed to larger catalytically active surfaces, were obtained compared with either the sepiolite clay mineral or the zirconium oxide tested individually.

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Lazaratou, Christina Vasiliki, Irene-Eva Triantaphyllidou, Ioannis Pantelidis, Dimitris A. Chalkias, George Kakogiannis, Dimitrios V. Vayenas, and Dimitrios Papoulis. "Using raw and thermally modified fibrous clay minerals as low concentration NH4+–N adsorbents." Environmental Science and Pollution Research 29, no. 12 (October 21, 2021): 17737–56. http://dx.doi.org/10.1007/s11356-021-17107-z.

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36

Shahbaz, A., A. Quintela, D. Terroso, J. Ribeiro, and F. Rocha. "Fibrous clay minerals as lithostratigraphic markers in a Cenozoic continental basin (Sado Basin, Portugal)." Applied Clay Science 119 (January 2016): 441–48. http://dx.doi.org/10.1016/j.clay.2015.11.006.

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Darder, Margarita, Charlene Regina Santos Matos, Pilar Aranda, Rubia Figueredo Gouveia, and Eduardo Ruiz-Hitzky. "Bionanocomposite foams based on the assembly of starch and alginate with sepiolite fibrous clay." Carbohydrate Polymers 157 (February 2017): 1933–39. http://dx.doi.org/10.1016/j.carbpol.2016.11.079.

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38

Aranda, Pilar, and Eduardo Ruiz-Hitzky. "Immobilization of Nanoparticles on Fibrous Clay Surfaces: Towards Promising Nanoplatforms for Advanced Functional Applications." Chemical Record 18, no. 7-8 (March 1, 2018): 1125–37. http://dx.doi.org/10.1002/tcr.201700113.

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Sabzi, Mohammad, Nima Shafagh, and Mohsen Mohammadi. "Assembly of gelatin biopolymer to fibrous sepiolite clay for efficient dye removal from wastewater." Journal of Applied Polymer Science 136, no. 48 (August 5, 2019): 48266. http://dx.doi.org/10.1002/app.48266.

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40

Lokhat, David, Irshaan Sewlala, Diajal Hooblal, and Bradley Paul. "Beneficiation of Sugarcane Bagasse Boiler Ash via Production of Syntactic Foams and Thermal Refractory Materials." Key Engineering Materials 779 (September 2018): 89–96. http://dx.doi.org/10.4028/www.scientific.net/kem.779.89.

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Aqueous solutions of sodium polytungstate were used to fractionate samples of sugarcane bagasse ash by heavy media separation. Practically no cenospheres were recovered from the ash samples. The method was successful in separating fibrous carbonaceous particles with a uniform surface from particles containing more silica and having a less uniform surface. A geopolymer refractory brick having satisfactory durability was produced from sugarcane bagasse ash with metakaolin and ball clay fillers and a sodium metasilicate/hydroxide activator liquor. Drying and firing shrinkage, bulk density and ultimate compressive strength tests were performed to determine the most feasible combination of ingredients. Geopolymer samples produced using aluminium powder instead of ball clay were found to be very brittle and unsuitable for refractory service.

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Zotiadis, V., and A. Argyraki. "Development of innovative environmental applications of attapulgite clay." Bulletin of the Geological Society of Greece 47, no. 2 (January 24, 2017): 992. http://dx.doi.org/10.12681/bgsg.11139.

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In this paper we present a series of laboratory and field, pilot- scale applications of attapulgite clay as an amendment for the stabilization of metals in contaminated soil and sewage sludge. Attapulgite’s structure together with its fine particle size and fibrous habit are responsible for its high specific surface area and sorption properties. A pilot scale application of attapulgite clay as a binder for in situ stabilization of toxic metals in contaminated land showed significant reduction in the water leachable metal fraction (Cu: 17%, Pb: 50%, Zn: 45%, Cd: 41%, Ag: 46%, As: 18%, Mn: 47%, Ba: 45%, Sb: 29%). In a second pilot scale environmental application, an innovative attapulgite “Geosynthetic Reactive Clay - GRC” was designed and developed for “capping” and “stabilization”of toxic metals in contaminated soil. Also, laboratory scale experiments with fresh sewage sludge from a municipal water treatment plant showed that addition of attapulgite clay in sludge, significantly reduced the leachable concentrations of phenol, DOC, Hg, Cu, Mo, Pb, Se, As, Zn and pathogen population over a 4 weeks observation period. The developed soil remediation techniques are promising and cost-effective under present market conditions. Concerning treatment of sewage sludge, attapulgite clay is an effective additive that could enhance the composting procedure creating an environmental added value, final compost product.

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SHIKINAKA, KAZUHIRO. "Creation of Functional Materials Consisting Nano‐Fibrous Clay Mineral / Nano‐Particulate Woody Biomass." Sen'i Gakkaishi 71, no. 10 (2015): P—486—P—490. http://dx.doi.org/10.2115/fiber.71.p-486.

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Park, Kyung-Lynne, Wei Ma, Yuji Higaki, and Atsushi Takahara. "Design and characterization of hybrid hydrogels composed of imogolite fibrous nanotubular clay and hyaluronic acid." Polymer 100 (September 2016): 238–43. http://dx.doi.org/10.1016/j.polymer.2016.08.018.

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González del Campo, M. Mar, Borja Caja-Munoz, Margarita Darder, Pilar Aranda, Luis Vázquez, and Eduardo Ruiz-Hitzky. "Ultrasound-assisted preparation of nanocomposites based on fibrous clay minerals and nanocellulose from microcrystalline cellulose." Applied Clay Science 189 (May 2020): 105538. http://dx.doi.org/10.1016/j.clay.2020.105538.

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Shirvani, Mehran, Hossein Shariatmadari, and Mahmoud Kalbasi. "Kinetics of cadmium desorption from fibrous silicate clay minerals: Influence of organic ligands and aging." Applied Clay Science 37, no. 1-2 (June 2007): 175–84. http://dx.doi.org/10.1016/j.clay.2006.12.010.

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46

Jamoussi, F., A. Ben Aboud, and A. López-Galindo. "Palygorskite genesis through silicate transformation in Tunisian continental Eocene deposits." Clay Minerals 38, no. 2 (June 2003): 187–99. http://dx.doi.org/10.1180/0009855033820088.

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AbstractThe mineralogical and geochemical characteristics of Eocene continental sediments in south central Tunisia (Chebket Bouloufa and Jebel Hamri) and in north central Tunisia (Jebel Lessouda and Jebel Rhéouis), which contain considerable amounts of palygorskite, were studied. The clay fraction of the sediments also comprises illite, kaolinite, Mg smectite and Al smectite, together with carbonates (calcite and/or dolomite), quartz, gypsum and feldspars, all of which are present in extremely variable proportions.The textural characteristics of the samples containing most palygorskite, as well as the chemical composition of the fibres and the contents of certain trace and rare earth elements suggest that the genesis of this fibrous clay is intimately linked to the diagenetic transformation of illite, mixedlayered minerals and/or Al smectite, as has also been observed in contemporaneous deposits in Morocco.

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47

Pietola, Liisa. "Effect of soil compactness on the growth and quality of carrot." Agricultural and Food Science 4, no. 2 (May 1, 1995): 139–237. http://dx.doi.org/10.23986/afsci.72611.

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Field experiments were performed in Southern Finland on three soil types: fine sand (1989-1991), clay (1989) and mull (1990-1991). The following soil mechanical treatments were applied to autumn ploughed land: soil loosening by ridge preparation (ridge distance 45 cm), rotary harrowing (to a depth of 20 cm, clay 15 cm), and soil compaction track by track by a tractor weighing 3 Mg (1 or 3 passes, wheel width 33 cm) before seed bed preparation. One plot was untreated. These treatments were set up in April (on clay in May) under moist soil conditions. Sprinkler irrigation (one application of 30 mm) was applied to clay and fine sand when soil moisture in top soil had decreased to around 50% of plant-available water capacity. PVC cylinders (r = 15 cm, h = 60 cm) were fixed in the experimental areas during the growing periods. At harvest, these cylinders were removed for specific analysis of tap and fibrous roots of carrot. Length and width of fibrous roots were quantified by image analysis in the USA. The impacts of soil loosening and partial compaction were determined by measuring soil physical parameters to a depth of 25 cm in mineral soils, and to greater depths in organic soil. Dry bulk densities of the plough layers increased with increasing tractor passes by 8%, 10% and 13% for fine sand, mull and clay soils, respectively. The lowest dry soil bulk density in the plough layer was obtained by rotary harrowing to a depth of 20 cm. Comparison of gamma ray transmission and gravimetric analysis indicated that dry soil bulk density was slightly lower when determined by gravimetric analysis. Increased soil bulk densities were reflected by increased water retention capacity (matric suction ≤ 10 kPa) and greater penetrometer resistance. Relatively similar increases in bulk density increased the penetrometer resistance much less in mull than in fine sand. In contrast, greater bulk densities in the mull soil affected soil air composition adversely by decreasing the O2 content to 10% when the subsoil had high wetness. In other soils, the lowest soil oxygen contents of 16-18% were recorded in early summer (compacted clay) and during periods of vigorous plant growth (fine sand) when soil water contents were high. Even though the highest degree of soil compactness (D) in a plough layer approached 93 (gravimetric) in all soils, only clay soil was compacted to a soil macro-porosity below 10% (pore diameter > 30 μm). Soil compaction promoted crop establishment and early growth as compared with loose soil beds. Optimum soil compactness for carrot yield (D = 82) was observed only in clay field where excess loosening or compaction affected yield quantity adversely at different stages of growth. During biomass accumulation, excessive penetrometer resistances limited tap root growth in compacted fine sand without irrigation. Water applications promoted shoot growth, but did not affect final shoot and tap root yield. Among the three soil types tested in this study, compaction of mull soil had the least effect on carrot growth and external quality. This paper presents evidence that the internal quality of carrots is only slightly affected by changes in soil physical properties, while the adverse effects of soil compaction on carrot external quality (short, deformed and conical tap roots with greater maximum diameters) are clear. Even though compacted clay soil greatly limited the biomass accumulations in the tap root, which had a high crude fibre content, the carotene (10 mg/100 g carrots) and sugar contents (5%) reached acceptable levels. The lowest carotene contents (4 mg/100 g carrots) were observed in loose mull, following a cool late summer in 1990. The effect of irrigation on carotene content varied from one year to another. High sugar and carotene contents appeared to respond to the high below-ground absorption surface. The fibrous root system of carrots, consisting of mostly very fine roots (diameter 0.15 mm), had total lengths of 150 m in loose fine sand at a soil depth of 0-50 cm (rotary harrowed), 200 m and 300 m in fine sand and mull soils subjected to 3 passes by a tractor wheel. The maximum dry weight (60 μg), length (1.2 cm) and surface area (0.05 cm2) of the fibrous root system per soil volume (cm3) were observed in compacted or irrigated soil to a depth of 30 cm, and also in relation to tap root dry weight. This suggests a capacity of carrot plant for high below-ground absorption potential and optimal biochemial maturation of tap root tissue even when surface soils are compacted. This is supported by higher leaf area, as the early shoot growth was promoted by partial soil compaction. Soil compaction affected the soil physical properties and carrot external quality in agreement with previous studies. Carotene and sugar contents appeared to be unaffected or were slightly increased in riper and firmer carrots of compacted soils. This is consistent with the earlier information about the internal quality of carrot which is shown to be highly dependent on genetic factors and developmental stage of carrot. The present study emphasizes the surface area of carrot fibrous root system as a beneficial factor for maintaining high levels of carotene and sugar contents in tap roots after partial soil compaction.

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Purvis, K. "Fibrous clay mineral collapse produced by beam damage of carbon-coated samples during scanning electron microscopy." Clay Minerals 26, no. 1 (March 1991): 141–45. http://dx.doi.org/10.1180/claymin.1991.026.1.12.

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Imane, Idoui, Rehab Bekkouche Souhila, Benzaid Riad, and Berdi Inas. "Use of Biopolymers in the Stabilization of Clay Soils." Selected Scientific Papers - Journal of Civil Engineering 16, no. 2 (December 1, 2021): 37–53. http://dx.doi.org/10.2478/sspjce-2021-0015.

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Abstract The treatment and stabilization of soils make it possible to recycle materials on construction sites in preparation for the installation of a final covering or the construction of a road network. In road geotechnics, various materials such as lime, cement, and pozzolans were used as additions to stabilize clay soils. In recent years, bio-polymers and bacteria are of increasing interest to researchers in the field of stabilization and improvement of the physico-mechanical and chemical characteristics of clay soils. Currently, in place of traditional clay treatment techniques and to minimize environmental problems, natural fibrous waste is being used increasingly and spectacularly. Several studies on biotechnological engineering applications already exist, such as the use of vegetation, algae, bacteria, enzymes, and biopolymers. The northern Algerian region where the urban tissue does not stop expanding contains significant potential in terms of wheat straw, which represents a very present agricultural waste. So, there is a local interest in the sustainable development of several regions known to produce wheat. This study is interested in investigating the effect of wheat straw on the stabilization of swelling clay soil. In order to improve the physico-mechanical characteristics of clay soils, a series of laboratory tests (Atterberg limit, Proctor test, direct shear test, Oedometer test, and unconfident compressive strength test) were carried out on reconstituted clay soil with defined initial properties through numerous analyses (e.g., XRD and XRF) and then treated with different vegetable fiber content. The results indicate that there is an improvement in the compressibility characteristics of the treated soil, a remarkable decrease in the swelling index and the compressibility index respectively with increasing percentages of wheat straw.

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Süzen, M. L., and A. G. Türkmenoğlu. "Lacustrine mineral facies and implications for estimation of palaeoenvironmental parameters: Neogene intervolcanic Pelitçik Basin (Galatean Volcanic Province), Turkey." Clay Minerals 35, no. 3 (June 2000): 461–75. http://dx.doi.org/10.1180/000985500546882.

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AbstractThe mineralogy of the Neogene lacustrine facies of Pelitçik basin was investigated for the purpose of deriving the palaeoenvironmental parameters of this intervolcanic basin. The laboratory studies indicate that dolomite and K-feldspar are the major non-clay minerals in the study area, where plagioclase, analcime, fibrous zeolite and quartz are the minor constituents. Dolomites are found to be non-stoichiometric in chemistry. The clay fraction of the lacustrine facies is composed mainly of dioctahedral smectites. The smectites are rich in Al-Fe indicating a detrital origin. Illite comprises a minor contribution to the clay fraction, where chlorite and kaolinite are found in trace amounts. Based on dolomite stoichiometry and the mineral paragenesis found in the Pelitçik basin, the depositional conditions are suggested to have been a shallow, quiet, perennial lacustrine environment with fresh to slightly saline and slightly alkaline water chemistry. In addition, based on geological and mineralogical constraints, it is suggested that the water chemistry fluctuated during the deposition of the Pazar formation and the lake began its evolution with a hydrologically closed system and completed its evolution with a hydrologically open system.

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Journal articles on the topic 'Fibrous clay'

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