Clay Research Articles

Mineralogy and Micromorphology Characteristic of Vertisol Lying on Limestone Parent Rocks at Jeneponto District of South Sulawesi Province, Indonesia

The objective of this is paper is to determine the mineralogy and micromorphology characteristics of vertisol in the limestone parent rock at Jeneponto district of South Sulawesi Province, Indonesia. The pedons represent deposits of volcanoes basalt. The study consisted of field and laboratory research. Field research comprises of soil profile descriptions and soil sampling, while laboratory analysis consists of clay minerals analysis using X-rays, as well as sand and rock mineral. Micromorphology analysis undisturbed soil samples were taken from identifiable horizon for thin section preparation. X-ray analysis revealed that clay minerals of the vertisol mainly consists of montmorillonite group. While the mineral composition of parent rock (limestone) generally consists of foraminifera fossil, calcite, dolomite, clay minerals, orthoclase, opaque minerals and quartz. The mineralogy of sand fraction generally consists of easily weathered minerals like pyroxene, feldspar, hornblende, plagioclase, biotite and hard weathered mineral (quartz and opaque). Soil micromorphology analysis revealed that raw material, in general is dominated by coarse material which is consist of quartz mineral mixed with other minerals such as pyroxene and plagioclase. On the other hand, organic coarse-sized components are not found and the microstructure of the soil is generally in the loose form (massive), and the type of soil pore vary from vugh to channels pore.

Direct Nitrous Oxide Emissions Related to Fertilizer-Nitrogen, Precipitation, and Soil Clay Fraction: Empirical Models

AbstractDirect nitrous oxide (N2O) emissions (DNEs) from croplands are required in national inventories of greenhouse gases. The Intergovernmental Panel on Climate Change (IPCC) guidelines provide an approach using direct emission factors (EFds) to estimate DNEs, which are constants for large regions. The goal of this paper is to establish empirical models to account for the temporal and spatial variations of EFds, which, apart from the nitrogen addition rate, also vary with a range of environmental factors, so as to enhance the accuracy of regional/national DNE estimates. Therefore, the seasonal/annual DNEs (n = 71) from upland croplands, which are the differences in N2O emissions between fields with and without fertilizer-nitrogen addition, were used to statistically relate DNEs to regulating factors including the fertilizer-nitrogen addition rate (FN), and environmental (climate and soil) factors. The multivariate stepwise linear regression results showed positive combined effects of Fn and clay fracti...

Congenital constriction ring of limbs in subjects with history of maternal substance use.

Congenital Constriction Ring (CCR) is a rare malformation which manifests itself in the form of ring-like constrictive bands. Due to its heterogeneous nature, its etiology remains unclear. Here, we present a series of seven independent individuals afflicted with CCR, which primarily involved the digits. The phenotypic manifestations included terminal phalangeal reduction, anonychia, digit hypoplasia, and acrosyndactyly. Mesoaxial digits in hands and preaxial digits in feet were most frequently affected. Camptodactyly and clubfoot were witnessed in four and one subject, respectively. Curiously, mothers of six of these subjects revealed that they consumed copious amounts of Multani mitti(Fuller's clay) and/or Naswar(nonsmoke-tobacco), during their respective pregnancies. Maternal substance use during pregnancy is not an unusual practice, however, its relationship with CCR as pregnancy outcome remains unexplored. Case-control studies are warranted to elucidate the relationship between the exposure to these substances and the etiology of CCR and/or other limb defects in the offspring.

Study on soil water characteristics of tobacco fields based on canonical correlation analysis

In order to identify the principal factors influencing soil water characteristics (SWC) and evaluate SWC effectively, the multivariate-statistical canonical correlation analysis (CCA) method was used to study and analyze the correlation between SWC and soil physical and chemical properties. Twenty-two soil samples were taken from 11 main tobacco-growing areas in Guizhou Province in China and the soil water characteristic curves (SWCC) and basic physical and chemical properties of the soil samples were determined. The results show that: (1) The soil bulk density, soil total porosity and soil capillary porosity have significant effects on SWC of tobacco fiels. Bulk density and total porosity are positively correlated with soil water retention characteristics (SWRC), and soil capillary porosity is positively correlated with soil water supply characteristics (SWSC). (2) Soil samples from different soil layers at the same soil sampling point show similarity or consistency in SWC. Inadequate soil water supply capability and imbalance between SWRC and SWSC are problems of tobacco soil. (3) The SWC of loamy clay are generally superior to those of silty clay loam.

Analyzing the fired-clay ceramic of EBA Canaanite pottery using FT-IR spectroscopy and LA-ICP-MS

The fired-clay ceramic of EBA (Early Bronze Age) Canaanite pottery is mineralogically and chemically analyzed by using FT-IR spectroscopy and LA-ICP-MS. Spectral analysis by second-derivative and curve-fitting techniques is applied to the FT-IR spectra in order to improve the identification of the compositional phases. In the firing of ceramics at temperatures no higher than 950 °C, the initial clay of the raw material is transformed into fired-clay, which is then defined as meta-clay. The meta-clay is characterized by a pseudo-amorphous, short-range ordered structure. The clay minerals kaolinite, smectite (montmorillonite) and illite are thermally transformed into metakaolinite, meta-smectite and meta-illite, respectively. In the present study, the fired-clay ceramic is analyzed in two specific classes of EBA Canaanite pottery: Metallic Ware (a group of ceramic) and holemouth cooking pots. The FT-IR spectroscopy and LA-ICP-MS results demonstrate that the major constituent of Metallic Ware is metakaolinite with quartz, indicating that kaolinitic raw material containing quartz was utilized for their manufacture. On the other hand, the major constituent of holemouth cooking pots is meta-smectite, indicating that smectitic raw material was used. An observation of both meta-clays in parts of the ceramics indicates that raw material consisting of a mixture of kaolinite and smectite was employed. The kaolinitic raw material was utilized for the manufacture of high-quality Metallic Ware because it does not swell or shrink upon wetting and drying, and can be fired to high temperatures to form impermeable, thin-walled durable vessels. However, for the manufacture of cooking pots a raw material that is stable in cooking directly over fire was required, and for this purpose smectitic raw material was utilized.

Numerical Analyses of Laboratory-Modelled Reinforced Stone Column

A stone column develops its vertical load carrying capacity by the lateral pressure provided by the surrounding soil. In very soft clay (C u ≤ 15 kPa), the stone column may not derive its load carrying capacity. Sometimes the formation of stone column is doubtful. In such cases, the stone column may be wrapped with geosynthetic peripherally (circumferentially). Normally, reinforced stone columns are used for widely spread areas like air tank foundation and embankment in which they confined by surrounding the columns. The performance of a small group of reinforced stone columns is complex. This communication focuses on the numerical modelling of a small group of laboratory- modelled reinforced stone columns. The study is carried out considering parameters like area replacement ratio (ARR), stiffness of reinforcement material and reinforcement length. The performance of reinforced stone column group is discussed in terms of bearing ratio, (q/C u )-settlement ratio, stress concentration factor and lateral deformation. The results of numerical analyses indicate that ARR and stiffness of geosynthetic are the governing parameters for enhancing the performance of reinforced stone column. The performance of partial reinforced stone column is close to that of a fully reinforced stone column.

Thin walled pottery from Alife (Northern Campania, Italy)

The ancient town of Allifae (modern Alife) represents one of the most interesting settlements of the Northern Campania area and together with the ancient city of Cales , was a thriving production centre of pottery. Excavations carried out inside the city wall, near the south gate, the so called, Porta Fiume, unearthed a huge dump of thin-walled ware, where the most abundant forms were cups and beakers, decorated with grooves or rouletting. The dump has been dated late Augustan/Tiberian age and the thin-walled vessels found can be identified with similar wares from Allifae, Cubulteria, Caiatia and perhaps Neapolis. Horace in his Sermones (II, 8,39) cited the Allifana beakers (described as fictiles ac subtiles by a Horace scholiast) and they could possibly be identified with the thin-walled wares produced in Allifae. If this the case, then the thin-walled vessels produced in Allifae were known in Rome as early as the end of I century B.C. In order to investigate and characterize the Allifae thin-walled pottery, twenty-one samples were selected and mineralogical-petrographic analyses (OM, XRD, XRF and SEM/EDS) were carried out. The clayey raw material used was a low-CaO alluvial clayey deposit from the Middle Valley of the Volturno River. The potters probably handled the sediment by a levigation process in order to remove the coarser grains, and making the clay suitable to produce such thin walls. Comparison with other regional production of thin-walled pottery allowed us to strictly distinguish the Allifana beakers.

Hydromorphic soils of Tripura: their pedogenesis and characteristics.

Hydromorphic soils that have developed on gently to very gently sloping flood plain areas of Tripura, North East India under humid tropical climate, were studied for characterization with reference to the degree of hydromorphism. The soils are characterized by the redoximorphic features, viz. mottling, gley with chroma 2 or less, and have a typical gley colour from the surface to subsoil, mostly influenced by the high groundwater level. These soils support the granary of the state. The degree of hydromorphism in these soils has been determined by the extent and distribution of mottles and gley in the profiles, which reflects the effect of the fluctuating groundwater table and depth of the permanent water table. The soils are deep to very deep with varying texture and drainage classes and have some common characters during pedogenesis under impeded drainage condition. Soils are acidic, medium to high in organic carbon, low in cation exchange capacity (CEC) and medium to high in base status. The low value of 1N KCl extractable Al +3 corroborates relatively high proportion of hydroxyinterlayered vermiculitic clay mineral present in the soil. Soil texture is found to be the key factor in developing hydromorphism as well as soil organic carbon stock in the hydromorphic soils of Tripura. Translocation of clay and free iron oxide (Fe d ) is generally prominent in the soils with medium to coarse texture. Based on the physical and chemical properties and the hydromorphic index, the soils can be arranged as Nayanpur > Dukli II > Dharaichherra > Dukli I > Goachand to indicate the degrees of hydromorphism.

RETRACTED ARTICLE: Synthesis, characterization and assessment thermal properties of clay based nanopigments

-montmorillonite, BB41 和 montmorillonite-BB41。NCP 的形态学被传播电子显微镜学也学习。最后， thermogravimetric 分析和微分 thermograms 建议设置的染料的热稳定性被改进。

Impacts of revegetation management modes on soil properties and vegetation ecological restoration in degraded sandy grassland in farming-pastoral ecotone.

Focusing on the impact of various vegetation management modes on sandy grassland’s soil property and vegetation ecological restoration of farming-pastoral ecotone, field surveys and lab analysis were conducted to study the correlation between the characteristics of soil properties and vegetation ecological restoration under four different vegetation management modes, i.e., unenclosed natural restoration, enclosed natural restoration, unenclosed artificial restoration and enclosed artificial restoration, which have a restoration history of 15 years in the southern edge of the degraded sandy land area of Mu Us Desert in Leilongwan Town, Hengshan County, Shaanxi Province. After 15 years of vegetation restoration, these four vegetation management modes all proved to be useful for improving the vegetation ecological restoration and the soil quality of the degraded sandy grassland not only by enhancing the aboveground vegetation height, coverage and biomass but also increasing the content of soil clay, organic matter, CEC, total nitrogen, available nutrient while reducing soil bulk density. The vegetation ecological restoration effect and soil quality under enclosed or artificial restoration management are better than those of unenclosed or natural restoration management; and the most satisfactory vegetation ecological restoration effects and soil quality can be achieved under the integration of enclosed and artificial restoration management. Severely degraded sandy grassland, during the vegetation restoration, would form an interactional coordinating relationship with the vegetation and soil properties. Vegetation properties as height, coverage and biomass have significant positive correlations with organic matter, CEC, total nitrogen and available nitrogen, phosphorus, and potassium contained in soil. Only the adoption of the strict enclosure system, implementation of aggressive artificial vegetation restoration measures and the realization of the regurgitation-feeding policy of industry towards husbandry can guarantee the gradual restoration of degraded sandy grassland in farming-pastoral ecotone, so that it can continue to play the role of ecological protective screen. DOI: 10.3965/j.ijabe.20150801.004 Citation: Fu B, Qi Y B, Chang Q R. Impacts of revegetation management modes on soil properties and vegetation ecological restoration in degraded sandy grassland in farming-pastoral ecotone. Int J Agric & Biol Eng, 2015; 8(1): 26－34.

Anisotropy of Magnetic Susceptibility of Earthquake-Affected Soft Sediments: Example from Ther Village, Latur, Maharashtra, India

Anisotropy of magnetic susceptibility (AMS) of deformed and undeformed unconsolidated clay samples of Deccan Trap terrain from the ~2000-year-old palaeoearthquake site of Ther village, Maharashtra, India, was studied. Such deposits are rare in this region and give an exceptional opportunity to test the efficacy of AMS and other magneto petrofabric studies, which can have a bearing on magnetic granularity ellipsoids, inclination and declination directions impacting palaeomagnetic studies. The undeformed clay samples exhibit typical sedimentary fabric with an oblate AMS ellipsoid, whereas the deformed samples are tightly grouped in the inferred compression direction, probably effected by an earthquake, exhibiting prolate as well as oblate AMS ellipsoids. The temperaturedependent magnetic susceptibility revealed the occurrence of titanomagnetite and magnetite in both the deformed and undeformed samples signifying similar sediment material. The site mean ChRM direction for undeformed clay samples is D = 3 and I = 44.7 ( k = 92.7, α 95 = 4.5), whereas for deformed samples D = 336 and I = 39 ( k = 39, α 95 = 8). The present study reveals that sediments can be severely deformed without deflecting minimum susceptibility directions. AMS methodology can be effective in the DT region and can throw up new results to build the chronology of past earthquakes.

Seepage analysis in body and foundation of Sang Siah Dam using the Seep/W

Abstract. One of the most important topics in designing of earth dams is determine the drainage rate in body and foundation of dam. The aim of this study is evaluating the seepage in body and foundation of Sang Siah dam, located in Kurdistan province of IRAN. Seepage analysis was done by SEEP/W software, from GEO STUDIO package. Three sections of Sang Siah dam were analyzed using SEEP/W software and the seepage rate was evaluated. Afterwards, the effects of cut off wall, clay blanket and concrete coverage were investigated with SEEP/W software. The free seepage line was analyzed by creating clay blanket, concrete coverage and cut off wall and it was revealed that clay blanket can be a good option in order to decreasing seepage of dam. Overall results showed that the seepage rate calculated using the software had 7-8% different with the actual measurements, due to differences in dam’s dimensions at various sections, anisotropic of soil, etc. The results were generally acceptable.

The influence of freeze-thaw cycles on the granulometric composition of Moscow morainic clay

ABSTRACT The freeze-thaw cycling process considerably changes the composition, structure, and properties of soils. Since the grain size is the most important factor in determining soil characteristics, our current research primarily aims to investigate dynamic changes of the soil fraction when exposed to freeze-t haw conditions. We observed two series of Moscow morainic clayey specimens (gQ IIm ): (I) the original series, and (II) the remolded series. We subjected each series of soil specimens to different frequencies of freeze-thaw cycles (3, 6, 20, and 40 cy cles), and we used granulometric tests to analyze both series before and after exposure to freeze-thaw conditions. As a resu lt of our experiments, the granulometric compositions tended to be distributed evenly after 40 freeze-thaw processes ( i.e. , content of fraction for 0.1–0.05 mm was increased after 40 freeze-thaw cycles) because the division of coarse grains and the aggregation of fine grains were synchronized during the freeze-thaw process. The soil grains in both series changed bi-directionally. In the original series, changes of the sand grains were conjugated with the clay grains, and in the remolded series, changes of the sand grains were conjugated with the silt grains, because potential energy difference caused the division and aggregation processes to relate to the coun-teraction process. The even distribution of soil grain size indicated the state of equilibrium or balance. The granulometric compositions were altered the most during the sixth freeze-thaw cycle, because the coefficient of the intensity variation of the grain fineness (

Baked clay

Baked clay

Studying the Sealing of Embankment dams (Case study: Boshar Dam (Tang sorkh Yasuj))

Abstract. By examining the long dams built in Iran, it is concluded that in many cases embankment dams with clay core are preferable and they are used as a good choice for the final plan. The water leakage is one of the major concerns of executives, consultants and contractors of dam constructions. In this study, we examined the Tang sorkh Yasuj dam and the results showed that it was very permeable due to the presence of about 15 m sediment in bulkhead profile and bedrock to a depth of 50 m, and there would be the possibility of water leakage by using seal walls in this way.

Fitting a Numerical Model for the Analysis of the Wet Bulb Dimensions by Drip Irrigation

Prevision of the unsaturated zone hydrodynamics is one of the most important criteria for designing efficiently localized irrigation practices. In Uruguay the design of localized irrigation has been historically based on formulations and previsions to quantify the size of the wet bulb, using different methods (analytical and numerical simulations, empirical and field tests). These methods were based on soil conditions for light and homogeneous soils, and arid climatic conditions, which are difficult to extrapolate to local soils and crops. Nowadays, is known to be common practice over irrigation because of the lack of a more accurate prevision of the shape of the wet bulb. However, there is no knowledge about the amount of deep percolating water. This research is based on the comparison of experimental results obtained from field test under controlled drip irrigation of alfalfa with the results of a numerical model that simulates unsteady hydrodynamic processes in unsaturated zone. The used code was CODE_ BRIGHT, developed by the Department of Geotechnical Engineering UPC, Barcelona, Spain. Tests were carried out modifying both the time of water application as the emitter discharges. A 1.20 m diameter and 1.20 m tall cylindrical lysimeter was built reproducing the original soil profile of the area. Each stratum was assumed to be homogeneous and axial symmetry was used to find the most efficient way to locate measuring instrumental. Percolating water volume was also measured in the experiment, placing a drainage system at the bottom of the lysimeter. The test was set up on the INIA Las Brujas facilities, using soils of the area (silty loam and silty clay loam) typical of the center-south of the country. The comparison of measured and predicted results suggests the existence of complex phenomena more based in soil structure than in soil texture, which may explain the rapid percolation observed on the initial stages of irrigation. It is necessary to develop other numerical models that represent more accurately these behavior.

Experimental chondrules by melting samples of olivine, clays and carbon with a CO2 laser

Los condros son los constituyentes principales de las meteoritas condriticas. Sin embargo, su formacion sigue siendo un enigma para la ciencia de la meteoritica. En este trabajo se reportan los resultados de la fusion de minerales para obtener fundidos tipo condro. El grado de fusion del olivino es un factor importante para determinar el ancho de las barras de las muestras tipo condros barrados de olivino (BO). Por otra parte, la contribucion de arcillas y carbon (posibles componentes de los granos precursores) es un factor importante en los experimentos en los que los fundidos generados tienen textura porfidica

How Irrigation Affects Soil Erosion Estimates of RUSLE2

RUSLE2 is a robust and computationally efficient conservation planning tool that estimates soil, climate, and land management effects on sheet and rill erosion and sediment delivery from hillslopes, and also estimates the size distribution and clay enrichment of sediment delivered to the channel system. In the U.S.A., RUSLE2 is supported by extensive databases maintained by the USDA-Natural Resources Conservation Service. Examples are presented of how input climate, soil and management descriptions might be built outside the U.S.A. using data from Uruguay. In addition to average annual erosion and sediment delivery, recent enhancements give RUSLE2 the ability to predict a representative runoff event sequence for a particular location, soil, management, and user-specified return period that can be coupled with a channel erosion and routing model.

Steam gasification of multiwire LiYCY type electrical cable

Original, non-separated pieces of the LiYCY cable (with multilayer metal/plastic (copper/PVC) structure) were gasified by steam in an excess at atmospheric pressure. Conversion of the gaseous stream was enhanced by catalytic bed of original granulated material, prepared from aluminosilicate (local clay) and calcium carbonate. In the process metal (Cu) preserved unchanged form of cords and braids and was quantitatively separated (49 % of original mass of the cable). Non-metal components (51 % of original mass of the cable) were converted to a slightly sintered non-metallic powder (3.3 % of original mass of the cable) and gaseous phase. Condensation of steam facilitated elimination of tars and oils as well as hydrochloride from the gas. It was estimated that only 5 % of carbon (from the cable components) was retained in the cooling/condensing line, mostly as water non-soluble phases. Efficiency of absorption of hydrochloride by catalytic bed and aqueous condensate was almost the same (but only 50 % of estimated total chlorine quantity was finally balanced).

Soil Organic Sequestration in Irrigations Farm of Black River Valley, Argentina

Larger water application by irrigation increases biomass productivity and consequently soil C input through residues and roots, changes mineralization rates, and alters the carbonate balance. Most irrigation is in areas with low levels of Soil Organic Matter (SOC) in the native state. Therefore, there is a large potential for carbon sequestration by the use of gravitational irrigation. Irrigated crops are grown on about 50.000 ha in the upper Valley with gravitational border and furrow irrigation system. For this work 29 farms located in Cipolletti Irrigation District, with crops pear and gravitational furrow irrigation. The edaphic variables selected: organic carbon, plantation age, soil texture, soil depth, soil drainage, pH and electrical conductivity. By using statistical programs multiple regressions equations, simulations of different scenarios allow to relate the stock of C ha-1 yr-1, according to variations in clay, the permanents years of irrigation and soil pH. The stock of t C ha-1 yr-1 have average values ranging from 0.50 t C ha-1 yr-1 the first 15 years, to 0.17 t C ha-1 in the next 30 years. The average carbon stock values are 0.28 t C ha-1 yr-1. Excessive irrigation, lack of proper drainage, and use of poor-quality irrigation water accentuate the risks of soil salinization. Use of proper irrigation methods and improved cropping systems is therefore essential to reap the benefits of irrigation in enhancing productivity and soil carbon sequestration. The gravitational irrigation border and furrow System minimizes the emission of CO2 and enhances carbon sequestration in the fight against global warming.