Etude granulometrique de la fraction sableuse des alluvions de la crue de juin 1957 sur le Guil (Hautes-Alpes)

1959 ◽  
Vol S7-I (6) ◽  
pp. 614-624
Author(s):  
Jean Tricart
Keyword(s):  
Sand Fraction ◽  
Parabolic Curve ◽  
Mechanical Suspension

Abstract Two fundamental types of curves (S-shaped and parabolic) were obtained in a granulometric study of the sand fraction of material carried by the Guil (France) in the flood of 1957. The S-shaped curve corresponds to well-sorted alluvium which has been transported in mechanical suspension and in which pebbles and gravels are rare; the parabolic curve corresponds to material whose transport has been obstructed. The effect of local geomorphic conditions on sedimentation was marked even in this violent flood.

scholarly journals Effect of Granulometric Composition of the Soil on the Occurrence of Carrion Beetles (Coleoptera: Silphidae)

2021 ◽  
Vol 11 (3) ◽  
pp. 1017
Author(s):  
Karolina Konieczna ◽  
Zbigniew W. Czerniakowski ◽  
Małgorzata Szostek
Keyword(s):  
Significant Relationship ◽  
Granulometric Composition ◽  
Clay Fraction ◽  
Total Abundance ◽  
Habitat Types ◽  
Sand Fraction ◽  
Positive Correlation ◽  
Nicrophorus Vespilloides ◽  
Carrion Beetle ◽  
Carrion Beetles

The entomological material was collected in the years 2009–2012 and 2014 from 13 different habitat types from three localities in south-eastern Poland. In total, 11,095 Silphidae were collected. This study examined whether the percentage of individual soil granulometric fractions was significantly related to the total abundance of collected Silphidae and individual carrion beetle species. A positive correlation and a statistically significant correlation were found between the total number of specimens collected and the share of the mechanical fraction with a diameter of 0.05–0.002 mm (silt fraction). In three species, a statistically significant correlation was demonstrated between the number of collected Silphidae and the share of the mechanical fraction with a diameter of 2–0.05 mm (sand fraction). The two species Phosphuga atrata atrata and Nicrophorus vespilloides the correlation was positive. A statistically significant relationship was also observed for Thanatophilus sinuatus, but the correlation was negative. With regard to the mechanical fraction with a diameter <0.002 mm (clay fraction), a statistically significant relationship was demonstrated for Oiceoptoma thoracicum and for Nicrophorus vespilloides for which the correlation was negative. However, a positive correlation was found for T. sinuatus in this case.

The mineralogical composition of some Scottish soils

1925 ◽  
Vol 15 (3) ◽  
pp. 257-271 ◽  
Author(s):  
James Hendrick ◽  
George Newlands
Keyword(s):  
Mineralogical Composition ◽  
Fine Sand ◽  
Plant Food ◽  
Sand Fraction ◽  
Extensive Survey ◽  
North East ◽  
The North ◽  
Local Origin ◽  
East West ◽  
Made In

1. Previous investigations showed that certain Scottish soils were of glacial drift origin, that they were comparatively rich in unweathered silicates and therefore in reserves of plant-food, that they showed considerable variation in such silicates and were capable of classification accordingly. Some indication was also shown that the glacial drift, and hence the resulting soil, was sometimes of local origin, its character being determined by the underlying rock. In the present investigation a more extensive survey of Scottish soils has been made in order to discover to what extent these preliminary findings might be applicable generally.2. For this purpose soils have been collected from various localities in the north, north-east, west and south of Scotland, and have been analysed mechanically and the “fine sand” fraction examined mineralogically.

Curve cracks lying along a parabolic curve in anisotropic body

1995 ◽  
Vol 16 (2) ◽  
pp. 115-124 ◽  
Author(s):  
Hu Yuan-tai ◽  
Zhao Xing-hua
Keyword(s):  
Anisotropic Body ◽  
Parabolic Curve

scholarly journals Study on Potassium Bearing Minerals in Sand Fraction Through X-Ray Diffraction Techniques

2013 ◽  
Vol 25 (1) ◽  
pp. 541-546
Author(s):  
R.S. Kaliramana ◽  
B.S. Pannu ◽  
J.P. Singh
Keyword(s):  
X Ray Diffraction ◽  
Sand Fraction ◽  
X Ray

Studies in the geology and mineralogy of soils: II. Soils of South-East Scotland

1929 ◽  
Vol 19 (4) ◽  
pp. 802-813 ◽  
Author(s):  
R. Hart
Keyword(s):  
Mineral Content ◽  
Mineralogical Composition ◽  
Fine Sand ◽  
Parent Material ◽  
The South ◽  
Sand Fraction ◽  
Silicate Minerals ◽  
Fresh State ◽  
The Matrix

(1) The mineralogical composition of the fine sand fraction of certain soils from the south-east of Scotland is described.(2) The soils are shown to possess a fairly high content of silicate minerals in a comparatively fresh state.(3) The distribution and amount of potash, phosphate and lime-bearing minerals in the soils is discussed.(4) The soils can be grouped according to their mineral content and this grouping is found to depend on the geology of the parent material.(5) All the soils are formed on glacial drift and the results suggest that the local rocks have a preponderating influence on the composition of the matrix of the drift.

scholarly journals Mineralogical characteristic of quaternary sediments (sand fraction) from the southern extremity of the Chukchi plateau, Arctic ocean

2019 ◽  
Vol 59 (4) ◽  
pp. 617-640
Author(s):  
O. N. Kolesnik ◽  
A. N. Kolesnik ◽  
E. G. Vologina ◽  
A. A. Maryash
Keyword(s):  
Arctic Ocean ◽  
Fine Sand ◽  
Quaternary Sediments ◽  
Mineralogical Analysis ◽  
Sand Fraction ◽  
Accessory Minerals ◽  
Stratigraphic Subdivision ◽  
Mineralogical Characteristic ◽  
Chukchi Plateau ◽  
Southern Extremity

The data on mineralogical analysis of fine sand fractions in sediments accumulated in the southern part of the Chukchi Plateau during the Quaternary are presented. The associations and downcore distribution of the rock-forming and accessory minerals in relation to other characteristics are considered. The established climatically controlled mineralogical features, i. e. periodicity of warmings and coolings, can be used in solving a number of genetic problems, stratigraphic subdivision of sediments and paleoreconstructions.

scholarly journals Generation of a double-crowned involute helical gear with twist-free tooth flanks by a CNC hobbing machine with three synchronous axes

2017 ◽  
Vol 39 (2) ◽  
pp. 97-108
Author(s):  
Van-The Tran
Keyword(s):  
Computer Simulation ◽  
Rotation Angle ◽  
Computer Numerical Control ◽  
Helical Gear ◽  
Numerical Control ◽  
Production Costs ◽  
Parabolic Curve ◽  
Transmission Errors ◽  
Simulation Results ◽  
Center Distance

In the conventional hobbing process, a double-crowned involute helical gear is generated by the hob cutter with parabolic-curve tooth profiles for the cross-profile crowning and varied the center distance between the hob and work gear for the longitudinal crowning. Therefore, to cut a double-crowned helical gear not only requires at least four synchronous axes and hob cutter regrinding (which increases production costs) but also induces twisted tooth flanks on the generated work gear. In this paper, I propose a hobbing method by applying a modified work gear rotation angle that enables double-crowning of involute helical gear's tooth flanks using a standard hob cutter and a computer numerical control (CNC) hobbing machine with only three synchronous axes. The proposed method has also verified by using two computer simulation examples to compare the meshing-conditions, contact ellipses, and transmission errors of the double-crowned gear pairs with that produced by applying the conventional hobbing method. Computer simulation results reveal the advantages of the proposed novel hobbing method.

scholarly journals Influence de la charge sur la production et la croissance de la vigne (c.v. Merlot)

OENO One ◽  
1987 ◽  
Vol 21 (2) ◽  
pp. 81
Author(s):  
M. Nikov
Keyword(s):  
Leaf Area ◽  
Shoot Growth ◽  
Inhibitory Effect ◽  
Yield Ratio ◽  
Primary Factor ◽  
First Year ◽  
Parabolic Curve ◽  
Grape Quality ◽  
Single Shoot ◽  
The Relationship

<p style="text-align: justify;">L'étude est menée avec le cépage Merlot conduit en forme haute et à une distance de 3,40 x 1,20 m. Les vignes supportent des charges individuelles de 26, 32, 38 ... jusqu'à 62 bourgeons par cep. La relation entre le nombre d'yeux et le rendement par souche se caractérise par une courbe parabolique avec un maximum autour de 50 bourgeons par cep. L'augmentation de charge au-delà de l'optimum exerce une influence inhibitrice sur la croissance des rameaux individuels depuis la première année. Le rapport entre la surface foliaire et la production représente un facteur essentiel pour la qualité du raisin.</p><p style="text-align: justify;">+++</p><p style="text-align: justify;">The study involves Merlot variety trained with an high trunk and a 3,40 x 1,20 m spacing. The vines support individual pruning levels of 26, 32, 38 ... up to 62 buds/vine. The relationship between bud number and yield per vine is characterized by a parabolic curve with a maximum around 50 buds/vine. The increase in pruning level beyond the optimum induces an inhibitory effect on single shoot growth since the first year. The leaf area : yield ratio represents a primary factor of grape quality.</p>

Estimated Placental Volume and Gestational Age

2017 ◽  
Vol 35 (08) ◽  
pp. 748-757
Author(s):  
Kimberly Isakov ◽  
John Emerson ◽  
Katherine Campbell ◽  
France Galerneau ◽  
Amber Anders ◽  
...  
Keyword(s):  
Birth Weight ◽  
Confidence Interval ◽  
Clinical Utility ◽  
Screening Tool ◽  
Placental Pathology ◽  
Parabolic Curve ◽  
Microscopic Evaluation ◽  
The Relationship ◽  
Placental Volume ◽  
Best Fit

Objective The objective of this study was to validate estimated placental volume (EPV) across a range of gestational ages (GAs). Study Design Three hundred sixty-six patients from 2009 to 2011 received ultrasound scans between 11 + 0 and 38 + 6 weeks GA to assess EPV. An EPV versus GA best fit curve was generated and compared with published normative curves of EPV versus GA in a different population. A subanalysis was performed to explore the relationship between EPV and birth weight (BW). Results Analysis of EPV versus GA revealed a parabolic curve with the following best fit equation: EPV = (0.372 GA − 0.00364 GA2)3. EPV was weakly correlated with BW, and patients with an EPV in the bottom 50th percentile had 2.42 times the odds of having a newborn with a BW in the bottom 50th percentile (95% confidence interval: 1.27–4.68). Microscopic evaluation of two placentas corresponding to the smallest EPV outliers revealed significant placental pathology. Conclusion Placental volume increases throughout gestation and follows a predictable parabolic curve, in agreement with the existing literature. Further validation is required, but EPV may have the potential for clinical utility as a screening tool in a variety of settings.

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