A classification of soil aggregates based on their coherence in water

Soil aggregates have been divided into seven classes by observing the coherence of the clay fraction after reacting aggregates with water. The reactions used were: immersion of dry aggregates in water, immersion of wet remoulded aggregates in water, and suspension of aggregates in water. One further class was distinguished by the presence of carbonate. Illite and montmorillonite clays were modified so as to exhibit the physical properties of some of the aggregate classes. The results with the clays were then used to explain the characteristic properties of aggregates derived from a wide variety of soils in the various classes. For example, class 2 aggregates show partial dispersion when placed, dry, in water. The minimum percentage of exchangeable sodium present in aggregates of this class was equal to that required for dispersion of the dry Na/Ca-clays immersed in water. Examples are given of where the detection of dispersion from aggregates can be useful in the field. As only simple tests are used, the proposed method of classification can be easily carried out under field conditions.

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The Classification of Parauapebas Meteorite: Petrological, Mineralogical and Elemental Compositions and Physical Properties

Planetary and Space Science ◽

10.1016/j.pss.2021.105250 ◽

2021 ◽

pp. 105250

Author(s):

Amanda A. Tosi ◽

Maria Elizabeth Zucolotto ◽

Wania Wolff ◽

Julio C. Mendes ◽

Sergio Suárez ◽

...

Keyword(s):

Physical Properties ◽

Elemental Compositions

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Blood platelet-derived microparticles release and bubble formation after an open-sea air dive

Applied Physiology Nutrition and Metabolism ◽

10.1139/h2012-067 ◽

2012 ◽

Vol 37 (5) ◽

pp. 888-892 ◽

Cited By ~ 19

Author(s):

Jean-Michel Pontier ◽

Emmanuel Gempp ◽

Mihaela Ignatescu

Keyword(s):

Platelet Aggregation ◽

Decompression Sickness ◽

Blood Platelets ◽

Water Immersion ◽

Bubble Formation ◽

Blood Platelet ◽

Field Conditions ◽

Control Group ◽

Open Sea ◽

Experimental Group

Bubble-induced platelet aggregation offers an index for evaluating decompression severity in humans and in a rat model of decompression sickness. Endothelial cells, blood platelets, or leukocytes shed microparticles (MP) upon activation and during cell apoptosis. The aim was to study blood platelet MP (PMP) release and bubble formation after a scuba-air dive in field conditions. Healthy, experienced divers were assigned to 1 experimental group (n = 10) with an open-sea air dive to 30 msw for 30 min and 1 control group (n = 5) during head-out water immersion for the same period. Bubble grades were monitored with a pulsed doppler according to Kissman Integrated Severity Score (KISS). Blood samples for platelet count (PC) and PMP (annexin V and CD41) were taken 1 h before and after exposure in both groups. The result showed a decrease in post-dive PC compared with pre-dive values in experimental group with no significant change in the control group. We observed a significant increase in PMP values after the dive while no change was revealed in the control group. There was a significant positive correlation between the PMP values after the dive and the KISS bubble score. The present study highlighted a relationship between the post-dive decrease in PC, platelet MP release, and bubble formation. Release of platelet MPs could reflect bubble-induced platelet aggregation and could play a key role in alteration of the coagulation. Further studies must investigate endothelial and leukocyte MP release in the same field conditions.

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Soil uses in the sugarcane fallow period to improve chemical and physical properties of two latosols (oxisols)

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832012000100029 ◽

2012 ◽

Vol 36 (1) ◽

pp. 283-294 ◽

Cited By ~ 6

Author(s):

Carolina Fernandes ◽

José Eduardo Corá ◽

Adolfo Valente Marcelo

Keyword(s):

Physical Properties ◽

Soil Aggregates ◽

Block Design ◽

Chemical Properties ◽

Aggregate Stability ◽

Fallow Period ◽

Growing Seasons ◽

Randomized Block Design ◽

Sunn Hemp ◽

In The Beginning

Sugarcane production should be integrated with crop diversification with a view to competitive and sustainable results in economic, social and environmental aspects. The purpose of this study was to assess the influence of different soil uses during the sugarcane fallow period on the chemical and physical properties of eutroferric Red Latosol - LVef (Oxisol) and Acric Latosol - LVw (Acric Oxisol), in Jaboticabal, São Paulo State, Brazil (21º14'05'' S, 48º17'09'' W, 600 m asl). A randomized block design was used with five replications and four treatments, consisting of different soil uses (crops) in the sugarcane fallow period: soybean only, soybean/fallow/soybean, soybean/millet/soybean, and soybean/sunn hemp/soybean. After two soybean crops, the LVef chemical properties remained at intermediate to high levels; while those of the LVw, classified as intermediate to high in the beginning, increased to high levels. Thus, the different soil uses during the sugarcane fallow period allowed the maintenance of LVef fertility levels and the improvement of those of the LVw. Two soybean crops increased macroporosity in the 0.0-0.1 m layer of the LVef; reduced soil aggregates in the 0.0-0.1 and 0.1-0.2 m layers of both soils, and reduced aggregate stability in these two layers of the LVw. Planting pearl millet or sunn hemp between the two soybean growing seasons promoted the formation of larger soil aggregates in the surface layer (0.0-0.1 m) of the LVw.

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Petrophysical Rocks: Electrofacies and Lithofacies

Principles of Mathematical Petrophysics ◽

10.1093/oso/9780199978045.003.0010 ◽

2014 ◽

Author(s):

John H. Doveton

Keyword(s):

Particle Size ◽

Physical Properties ◽

Sedimentary Rocks ◽

Well Control ◽

The Core ◽

Lateral Extent ◽

Petrophysical Logs ◽

Definition Of

Many years ago, the classification of sedimentary rocks was largely descriptive and relied primarily on petrographic methods for composition and granulometry for particle size. The compositional aspect broadly matches the goals of the previous chapter in estimating mineral content from petrophysical logs. With the development of sedimentology, sedimentary rocks were now considered in terms of the depositional environment in which they originated. Uniformitarianism, the doctrine that the present is the key to the past, linked the formation of sediments in the modern day to their ancient lithified equivalents. Classification was now structured in terms of genesis and formalized in the concept of “facies.” A widely quoted definition of facies was given by Reading (1978) who stated, “A facies should ideally be a distinctive rock that forms under certain conditions of sedimentation reflecting a particular process or environment.” This concept identifies facies as process products which, when lithified in the subsurface, form genetic units that can be correlated with well control to establish the geological architecture of a field. The matching of facies with modern depositional analogs means that dimensional measures, such as shape and lateral extent, can be used to condition reasonable geomodels, particularly when well control is sparse or nonuniform. Most wells are logged rather than cored, so that the identification of facies in cores usually provides only a modicum of information to characterize the architecture of an entire field. Consequently, many studies have been made to predict lithofacies from log measurements in order to augment core observations in the development of a satisfactory geomodel that describes the structure of genetic layers across a field. The term “electrofacies” was introduced by Serra and Abbott (1980) as a way to characterize collective associations of log responses that are linked with geological attributes. They defined electrofacies to be “the set of log responses which characterizes a bed and permits it to be distinguished from the others.” Electrofacies are clearly determined by geology, because physical properties of rocks. The intent of electrofacies identification is generally to match them with lithofacies identified in the core or an outcrop.

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PRODUCTION OF PARTICLE BOARDS USING POLYSTYRENE AND BAMBOO WASTES

Nigerian Journal of Technology ◽

10.4314/njt.v36i3.18 ◽

2017 ◽

Vol 36 (3) ◽

pp. 788-793

Author(s):

SA Abdulkareem ◽

AG Adeniyi

Keyword(s):

Physical Properties ◽

National Standards ◽

Low Density ◽

Thickness Swelling ◽

The Matrix ◽

Curing Methods

This investigation was able to produce incredibly strong particleboards using bamboo and resinous material obtained from Polystyrene wastes. The particleboards were prepared by mixing the bamboo fibres and Polystyrene based resin (PBR) followed by flat press process at different ratio (v/v). Physical properties were measured, with reference to normal and oven curing methods, according to the ASTM D-1037 standard. Thickness Swelling (TS) of the samples were measured after 2 and 24 hours of immersion in water at 25oC temperature. It was found that the physical properties of particleboards with 20%, 30% and 40% PBR content were all in agreement with low density particleboard classification of American National Standards Institute (ANSI). TS increased as the PBR content decreased in the matrix. Obtained properties convincingly indicate superior bonding ability of the synthesised resinous polystyrene over known industrial adhesives typically used for particleboard production. http://dx.doi.org/10.4314/njt.v36i3.18Â

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The stability of soils used for cropping in northern Victoria and southern New South Wales

Soil Research ◽

10.1071/sr00088 ◽

2002 ◽

Vol 40 (4) ◽

pp. 615 ◽

Cited By ~ 5

Author(s):

W. H. Vance ◽

B. M. McKenzie ◽

J. M. Tisdall

Keyword(s):

New South ◽

Soil Samples ◽

Exchangeable Sodium Percentage ◽

Exchangeable Sodium ◽

Sodic Soil ◽

Mechanical Dispersion ◽

South Wales ◽

Dispersion Test ◽

The Stability

Three hundred and six soil samples were classified for sodicity on the basis of exchangeable sodium percentage (ESP), and for spontaneous or mechanical dispersion on the basis of a dispersion test (Emerson 1991). Each sample was analysed for pH, electrical conductivity (EC), concentrations of exchangeable and soluble cations (Ca2+, Mg2+, Na+, K+), and concentration of organic carbon (OC). These variables were used to explain the sodicity and dispersive classifications of the 306 samples. Concentrations of exchangeable and soluble Ca2+, Mg2+, and Na+ along with EC and total cation concentration (TCC) significantly affected the sodicity and dispersion classification of the soil. A sodic soil was expected to disperse spontaneously, a non-sodic soil was not expected to disperse spontaneously. From this hypothesis the expected and observed dispersion class was compared with sodicity class. The expected result corresponded to the observed result 77% of the time and the hypothesis was accepted (P < 0.001).

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Classification of Theories about Rock Pressure

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.277.157 ◽

2018 ◽

Vol 277 ◽

pp. 157-167 ◽

Cited By ~ 8

Author(s):

Oleh Khomenko ◽

Maksym Kononenko ◽

Janchiv Bilegsaikhan

Keyword(s):

Physical Properties ◽

Rock Pressure ◽

Mine Working ◽

Physical Processes ◽

Classification Feature ◽

The World ◽

Underground Mine Working ◽

Mine Workings ◽

Energy Theory

The first classificationsw of physical properties of rocks and hypotheses of rock pressure in the world practice are analysed. The analysis of internationally widely known theories about rock pressure and physical processes around mine workings is executed. Classification of theories about rock pressure on classification feature “condition of investigated massif” is constructed. The energy theory that describing capsulation by the massif of underground mine working is offered.

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Using Deep Learning for Image-Based Different Degrees of Ginkgo Leaf Disease Classification

Information ◽

10.3390/info11020095 ◽

2020 ◽

Vol 11 (2) ◽

pp. 95 ◽

Cited By ~ 1

Author(s):

Kaizhou Li ◽

Jianhui Lin ◽

Jinrong Liu ◽

Yandong Zhao

Keyword(s):

Deep Learning ◽

Ginkgo Biloba ◽

Plant Disease ◽

Disease Classification ◽

Field Conditions ◽

Laboratory Conditions ◽

Leaf Disease ◽

And Training ◽

Ginkgo Leaf

Diseases from Ginkgo biloba have brought great losses to medicine and the economy. Therefore, if the degree of disease can be automatically identified in Ginkgo biloba leaves, people will take appropriate measures to avoid losses in advance. Deep learning has made great achievements in plant disease identification and classification. For this paper, the convolution neural network model was used to classify the different degrees of ginkgo leaf disease. This study used the VGGNet-16 and Inception V3 models. After preprocessing and training 1322 original images under laboratory conditions and 2408 original images under field conditions, 98.44% accuracy was achieved under laboratory conditions and 92.19% under field conditions with the VGG model. The Inception V3 model achieved 92.3% accuracy under laboratory conditions and 93.2% under field conditions. Thus, the Inception V3 model structure was more suitable for field conditions. To our knowledge, there is very little research on the classification of different degrees of the same plant disease. The success of this study will have a significant impact on the prediction and early prevention of ginkgo leaf blight.

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Isospectral drums and simple groups

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887818500603 ◽

2018 ◽

Vol 15 (04) ◽

pp. 1850060

Author(s):

Koen Thas

Keyword(s):

Physical Properties ◽

The Other ◽

Simple Groups ◽

Finite Simple Groups ◽

Planar Domains ◽

Other Hand ◽

Isospectral Manifolds ◽

Transplantation Technique ◽

Rule Out

Nearly every known pair of isospectral but nonisometric manifolds — with as most famous members isospectral bounded [Formula: see text]-planar domains which makes one “not hear the shape of a drum” [M. Kac, Can one hear the shape of a drum? Amer. Math. Monthly 73(4 part 2) (1966) 1–23] — arise from the (group theoretical) Gassmann–Sunada method. Moreover, all the known [Formula: see text]-planar examples (so counter examples to Kac’s question) are constructed through a famous specialization of this method, called transplantation. We first describe a number of very general classes of length equivalent manifolds, with as particular cases isospectral manifolds, in each of the constructions starting from a given example that arises itself from the Gassmann–Sunada method. The constructions include the examples arising from the transplantation technique (and thus in particular the known planar examples). To that end, we introduce four properties — called FF, MAX, PAIR and INV — inspired by natural physical properties (which rule out trivial constructions), that are satisfied for each of the known planar examples. Vice versa, we show that length equivalent manifolds with FF, MAX, PAIR and INV which arise from the Gassmann–Sunada method, must fall under one of our prior constructions, thus describing a precise classification of these objects. Due to the nature of our constructions and properties, a deep connection with finite simple groups occurs which seems, perhaps, rather surprising in the context of this paper. On the other hand, our properties define in some sense physically irreducible pairs of length equivalent manifolds — “atoms” of general pairs of length equivalent manifolds, in that such a general pair of manifolds is patched up out of irreducible pairs — and that is precisely what simple groups are for general groups.

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