المؤلفون: Shengnan Ma, Yi Song, Jiawei Liu, Xingyu Kang, Zhongqi Quentin Yue

المصدر: Journal of Rock Mechanics and Geotechnical Engineering, Vol 16, Iss 1, Pp 242-257 (2024)

مصطلحات موضوعية: Particle size distribution (PSD), General soil, Silt, Clay, Wet sieving, Physical and chemical properties, Engineering geology. Rock mechanics. Soil mechanics. Underground construction, TA703-712

الوصف: The traditional standard wet sieving method uses steel sieves with aperture ≥0.063 mm and can only determine the particle size distribution (PSD) of gravel and sand in general soil. This paper extends the traditional method and presents an extended wet sieving method. The extended method uses both the steel sieves and the nylon filter cloth sieves. The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm, 0.038 mm, 0.014 mm, 0.012 mm, 0.0063 mm, 0.004 mm, 0.003 mm, 0.002 mm, and 0.001 mm, respectively. The extended method uses five steps to separate the general soil into many material sub-groups of gravel, sand, silt and clay with known particle size ranges. The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups. The extended method is demonstrated with a general soil of completely decomposed granite (CDG) in Hong Kong, China. The silt and clay materials with different particle size ranges are further examined, checked and verified using stereomicroscopic observation, physical and chemical property tests. The results further confirm the correctness of the extended wet sieving method.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S1674775523000987Test; https://doaj.org/toc/1674-7755Test

الوصول الحر: https://doaj.org/article/26a98e0c74c042268c9ea109d6e642f6Test

المؤلفون: Yikai Zhao, Han Wang, Xiangwei Chen, Yu Fu

المصدر: Geoderma, Vol 439, Iss , Pp 116698- (2023)

مصطلحات موضوعية: Soil aggregates, Wet-sieving, Swelling, Adsorption, Filling, Science

الوصف: Soil aggregates swell when infiltrated by water, and their size can increase in two ways. First, aggregates can attach to one another with water acting as a bridge (i.e., adsorption), and water can enter the aggregate pores (i.e., swelling). This is defined as the “adsorption-swelling” effect. Second, clay can fill the pores of macroaggregates and microaggregates (i.e., filling) when adsorption occurs. This is defined as the “adsorption-filling” effect. However, the size range of aggregates affected by these effects and the extent of their influence on aggregate swelling are still unclear. Therefore, different initial size fractions (5 ∼ 2, 2 ∼ 1, 1 ∼ 0.5, 0.5 ∼ 0.25 and 0.25 ∼ 0.053 mm) of soil aggregates from the black soil zone of Northeast China were studied. The size range of swollen aggregates, the “adsorption-swelling” rate (V) of initial size fractions, and the “adsorption-filling” rate (E) of size fractions

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S0016706123003750Test; https://doaj.org/toc/1872-6259Test

الوصول الحر: https://doaj.org/article/50abf56237ca46af922568002d5fb96cTest

المؤلفون: Siebe Lievens, Evelynn Vervoort, Giulia Poma, Adrian Covaci, Mik Van Der Borght

المصدر: Methods and Protocols; Volume 6; Issue 1; Pages: 15

مصطلحات موضوعية: microplastics, cryogenic grinding, separation, wet sieving, PVC

الوصف: Concerns about the presence of microplastics in the environment has increased in recent years, prompting more attention from scientists. Thorough exposure studies using artificially produced microplastics containing additives are required to assess their potentially hazardous effects. Therefore, an efficient microplastic production and fractionation protocol was established using a cryogenic grinding and wet-sieving approach. The developed cryogenic grinding method was able to produce (20–40 g/h) polyvinyl chloride (PVC) microplastics having a volume-weighted mean particle size of 391 µm and a span of 2.12. Performing a second grinding cycle on the same particles resulted in microplastics which were smaller (volume-weighted mean size = 219 μm) and had a narrower particle size distribution (span = 1.59). In addition, the microplastics were also fractionated into different particle size ranges using a vibrating wet-sieving tower. The latter technique allowed separating 10 g of PVC microplastics into seven different fractions using six sieves (Ø 200 mm) for 30 min while shaking. By using the developed method, PVC microplastics could easily be made and fractionated into desired particle-size ranges. The proposed protocol could also be adjusted to produce and fractionate microplastics of other plastics.

وصف الملف: application/pdf

العلاقة: Biochemical and Chemical Analysis & Synthesis; https://dx.doi.org/10.3390/mps6010015Test

الإتاحة: https://doi.org/10.3390/mps6010015Test

المؤلفون: Larissa Schwinghammer, Steffen Krause, Christian Schaum

المصدر: Water Science and Technology, Vol 84, Iss 2, Pp 384-392 (2021)

مصطلحات موضوعية: atr-ftir, compost, co-substrates, dewatered digested sludge, microplastics, wet-sieving, Environmental technology. Sanitary engineering, TD1-1066

الوصف: Dewatered digested sludge and compost may act as a conduit for microplastics (

وصف الملف: electronic resource

العلاقة: http://wst.iwaponline.com/content/84/2/384Test; https://doaj.org/toc/0273-1223Test; https://doaj.org/toc/1996-9732Test

الوصول الحر: https://doaj.org/article/4149fc0993fe482b9a71f224bcfa712cTest

المؤلفون: Rando Sekiguchi, Hirotaka Saito, Haruo Tanaka, Yuji Kohgo

المصدر: Soil Systems; Volume 6; Issue 2; Pages: 51

مصطلحات موضوعية: aggregate stability, temperature dependence, wet sieving, mechanical disaggregation, vulnerability index, volcanic ash soils, andosols

جغرافية الموضوع: agris

الوصف: Volcanic ash soil aggregates can be disaggregated using heat under wet conditions. This study aimed to investigate factors affecting the disaggregation of volcanic ash soil aggregates in a field with organic cattle manure (M plot) and a field with chemical fertilizer (F plot) that were exposed to heat. The two-step wet sieving method, in which aggregates were sieved twice at different water temperatures for different times, was used to investigate the disaggregation caused by heat. It was found that increasing the temperature during the second sieve was more effective in disaggregating aggregates than extending the second-step sieve time. When the water temperature was increased to 80 °C, macroaggregates became more vulnerable, especially those in the F plot. The total carbon (TC) remaining in the soil aggregates was also measured after sieving. Although the TC content in aggregates decreased after sieving, there was only a minor relationship between decreasing TC content and the degree of disaggregation. This suggests that aggregates were not disaggregated by eluting binding agents containing carbon contents, but by partial breakage of the binding agent and/or the peeling of particles with binding agents from the aggregates.

وصف الملف: application/pdf

العلاقة: https://dx.doi.org/10.3390/soilsystems6020051Test

الإتاحة: https://doi.org/10.3390/soilsystems6020051Test

المؤلفون: Nan Zheng, Min Luo, Danyang Meng, Diandou Xu, Zhiming Liu, Yang Shao, Lingling Ma

المصدر: Processes; Volume 10; Issue 2; Pages: 216

مصطلحات موضوعية: soil aggregates, wet sieving, dry sieving, inorganic chlorine, heavy metals

جغرافية الموضوع: agris

الوصف: To study the distribution characteristics of typical pollutants in soil aggregates using different sieving methods, urban and arable soils were collected from Beijing and separated to different sizes by dry and wet sieving methods, to analyze present concentrations of inorganic chlorine and nine typical heavy metals (Cr, Mn, Co, Ni, Cu, Zn, Cd, As, and Pb). Results revealed that the distribution of wet-sieved aggregates was biased towards microaggregates (<250 μm), while the contrary result was found for the dry sieving method. Inorganic chlorine was more likely to be enriched in <53 μm fractions attained by both sieving methods. However, the content of inorganic chlorine in wet-sieved aggregates was significantly lower than in those that were dry sieved, which means the water’s effect on soluble ions was more pronounced. Heavy metals in urban soils were preferentially enriched in microaggregates no matter what kind of sieving method was applied. As for Mn and As found in agricultural soils using the dry sieving method, they were preferentially enriched in the fractions of 1000–2000 μm and 250–1000 μm, while the other seven heavy metals were preferentially enriched in <53 μm fractions, indicating that Mn and As in agricultural soils were easily transferred in aggregates with different particle sizes. Samples with particle sizes <53 μm showed the highest distribution factors for all heavy metals when the wet sieving method was applied. The dry sieving method resulted in a higher mass loading of heavy metals in coarser fractions and lower proportions in finer fractions. Results of a potential ecological risk analysis showed that the ecological risk (Eri) value of Cd found in aggregates by the different sieving methods was significantly different (p < 0.05). The findings suggest that different sieving methods could result in different occurrence patterns of pollutants in the soil aggregates of different land use types.

وصف الملف: application/pdf

العلاقة: Environmental and Green Processes; https://dx.doi.org/10.3390/pr10020216Test

الإتاحة: https://doi.org/10.3390/pr10020216Test

المؤلفون: You, Defang, Stein, Ruediger, Fahl, Kirsten, Schefuß, Enno

مصطلحات موضوعية: AGE, Biomarkers, Coarse fraction, DEPTH, sediment/rock, Foraminifera, GC, Gravity corer, Ice Sheet, Irminger Current, Labrador Sea, Maria S. Merian, MSM12/2, MSM12/2_647-1, MSM12/2-05-01, Sea surface, Size fraction > 0.063 mm, sand, Wet sieving, XRF

جغرافية الموضوع: LATITUDE: 57.538500 * LONGITUDE: -48.738700 * DATE/TIME START: 2009-06-30T06:34:00 * DATE/TIME END: 2009-06-30T06:34:00 * MINIMUM DEPTH, sediment/rock: 0.1975 m * MAXIMUM DEPTH, sediment/rock: 14.9050 m

الوصف: This dataset includes the percentage of fractions above 63 microns of Core MSM12/2-05-01 from the eastern Labrador Sea. Here, we show the record representing the last 50 ka.

وصف الملف: text/tab-separated-values, 114 data points

العلاقة: https://doi.org/10.1594/PANGAEA.965118Test; https://doi.pangaea.de/10.1594/PANGAEA.965380Test; https://doi.org/10.1594/PANGAEA.965380Test

الإتاحة: https://doi.org/10.1594/PANGAEA.96538010.1594/PANGAEA.965118Test

المؤلفون: Érika Andressa Silva, Micael Stolben Mallmann, Monike Andrade Pereira, Sarah Severo Pons, Felipe Dalla –Zen Bertol, Dalvan José Reinert, José Miguel Reichert

المصدر: Revista Brasileira de Engenharia de Biossistemas, Vol 15, Iss 2 (2021)

مصطلحات موضوعية: Amplitude of vibration, Ultrasound, Wet sieving., Environmental technology. Sanitary engineering, TD1-1066, Biotechnology, TP248.13-248.65, Science (General), Q1-390

الوصف: Ultrasonic-based techniques allow the prediction of the energy required to break the aggregate and have been more commonly used to measure the stability of aggregates. Although they result in the same applied energy, certain combinations of time and power might correspond to different intensities of cavitation. Consequently, different responses in aggregation indexes can be obtained with different configurations of ultrasound techniques. Thus, this work was carried out to evaluate the effects of cavitation intensity in the distribution of aggregates of a Paleudalf under management systems with cover plants and to compare aggregate stability determination methods (ultrasound versus wet sieving). Aggregate samples of the BS (bare soil), OT (black oat + forage turnips) and OV (black oat + hairy vetch) treatments were exposed to ultrasonic irradiation in different combinations of potency and time: (U1) 74.5 W/4 s; (U2) 49.7 W/6 s; (U3) 74.5 W/10 s and (U4) 49.7 W/15 s. After each sonification, the samples were passed in the same set of sieves used in the standard method of wet sieving -WS (8.00 - 4.76, 4.76 - 2.00, 2.00 - 1.00, 1.00 - 0.25 and < 0.25 mm) and the geometric mean diameter (GMD) and mass-weighted mean diameter (WMD) were calculated. The amplitude of vibration exerted a greater influence on soil breakdown than the total energy applied. Compared to the ultrasound method, in the WS method observed higher percentage of retained aggregates in the size class 8-4.76 mm and, consequently, greater aggregation indexes GMD and WMD.

وصف الملف: electronic resource

العلاقة: https://seer.tupa.unesp.br/index.php/BIOENG/article/view/961Test; https://doaj.org/toc/1981-7061Test; https://doaj.org/toc/2359-6724Test

الوصول الحر: https://doaj.org/article/f951dd8c55244c2684fa2c88447cc5eaTest

المؤلفون: Fakher Abbas, Fang Lin, Zhaolong Zhu, Shaoshan An

المصدر: Sustainability; Volume 13; Issue 8; Pages: 4229

مصطلحات موضوعية: relative stability, aggregate stability, soil aggregate, ultrasonic agitation, wet sieving

جغرافية الموضوع: agris

الوصف: As soil stability is a complex phenomenon, various methods and indexes were introduced to assess the strength of soils. Because of the limitations of different stability methods and indexes (including wet sieving-based), we aimed to presents a relative stability index (RI) that was based on the estimated components of the soil overall disruptive characteristic curve (SODC): (1) soil disruption constant (Ki, that is based upon dispersion energy of soils); (2) resulting change in mean weight diameter (ΔMWD). To evaluate the effectiveness and limitations of RI as well as to compare it with classical soil stability indexes of mean weight diameter (MWD) and geometric mean diameter (GMD). Ultrasonic agitation (UA) along with a wet sieving method (followed by dry sieving) was applied against four different soils named on the basis of sample location, Qingling soil (QL), Guanzhong soil (GZ), Ansai soil (AS), and Jingbian soil (JB). To evaluate the relative strength of soils at different applied energies (increase in sonication duration usually resulted in increased input energy and temperature of soil–water suspension), soils were subjected to six sonication durations (0, 30, 60, 120, 210, and 300 s) with a fixed (and exact) initial amplitude and temperature. Output energy was calculated based on the amplitude and temperature of the suspension, vessel, and system. The most abrupt and maximum disruption of soil aggregates was observed at a dispersion energy level of 0–200 J g−1. The MWD value of surface and subsurface ranged between 0.58 to 0.15 mm and 0.37 to 0.17 mm, respectively, while GMD was ranged from 0.14 to 0.33 mm overall. The results for MWD and GMD showed a similar trend. MWD and GMD showed more strong associations with physicochemical characteristics of soil than RI. A non-significant correlation was found between RI and MWD/GMD. Contrary to MWD and GMD, RI was significantly positively correlated with sand content; this finding indicated the influential role of sand in assessing the soil’s relative strength. ...

وصف الملف: application/pdf

العلاقة: Sustainability, Biodiversity and Conservation; https://dx.doi.org/10.3390/su13084229Test

الإتاحة: https://doi.org/10.3390/su13084229Test

المؤلفون: Sergio Andò

المصدر: Minerals; Volume 10; Issue 3; Pages: 273

مصطلحات موضوعية: handbook for laboratory procedures, nontoxic heavy liquids, wet sieving of silt, size-window for analysis, zircon separation, heavy-mineral mounts, provenance analysis

جغرافية الموضوع: agris

الوصف: The potential of heavy minerals studies in provenance analysis can be enhanced conspicuously by using a state-of-the-art protocol for sample preparation in the laboratory, which represents the first fundamental step of any geological research. The classical method of gravimetric separation is based on the properties of detrital minerals, principally their grain size and density, and its efficiency depends on the procedure followed and on the technical skills of the operator. Heavy-mineral studies in the past have been traditionally focused on the sand fraction, generally choosing a narrow grain-size window for analysis, an approach that is bound to introduce a serious bias by neglecting a large, and sometimes very large, part of the heavy-mineral spectrum present in the sample. In order to minimize bias, not only the largest possible size range in each sample should be considered, but also, the same quantitative analytical methods should be applied to the largest possible grain-size range occurring in the sediment system down to 5 μm or less, thus including suspended load in rivers, loess deposits, and shallow to deep-marine muds. Wherever the bulk sample cannot be used for practical reasons, we need to routinely analyze the medium silt to medium sand range (15–500 μm) for sand and the fine silt to sand range (5–63 or > 63 μm) for silt. This article is conceived as a practical handbook dedicated specifically to Master and PhD students at the beginning of their heavy-mineral apprenticeship, as to more expert operators from the industry and academy to help improving the quality of heavy-mineral separation for any possible field of application.

وصف الملف: application/pdf

العلاقة: Mineral Deposits; https://dx.doi.org/10.3390/min10030273Test

الإتاحة: https://doi.org/10.3390/min10030273Test