Laboratory measure of SWCC for a poorly graded fine sand

The Taylor Aggression Paradigm (TAP) is a frequently-used laboratory measure of aggressive behavior. However, the flexibility inherent in its implementation and analysis can undermine its validity. To test whether the TAP was a valid aggression measure irrespective of this flexibility, I conducted a preregistered study of a 25-trial version of the TAP using a single scoring approach with 160 diverse undergraduate participants. TAP scores showed agreement with other laboratory aggression measures and were magnified by an experimental provocation manipulation. Mixed evidence was found for associations with aggressive dispositions and real-world violence. These results provide preliminary support for this approach to the TAP to measure state-level aggressive behavior. However, more evidence is needed to assess the TAP’s external validity and ability to measure dispositional forms of aggression. Using preregistered designs, researchers should validate specific variants of their behavioral tasks in order to optimize the veridicality and reproducibility of psychological science.

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Impact of Nitrogen Management Practices on Total Nitrogen in the Fruits of High Productive Hamlin Orange Trees

HortScience ◽

10.21273/hortsci.33.3.498e ◽

1998 ◽

Vol 33 (3) ◽

pp. 498e-498

Author(s):

S. Paramasivam ◽

A.K. Alva

Keyword(s):

Crop Production ◽

Management Practices ◽

Fine Sand ◽

Fruit Production ◽

Perennial Crop ◽

Total N ◽

N Removal ◽

Leaf N Concentration ◽

N Rates ◽

Orange Trees

For perennial crop production conditions, major portion of nutrient removal from the soil-tree system is that in harvested fruits. Nitrogen in the fruits was calculated for 22-year-old `Hamlin' orange (Citrus sinensis) trees on Cleopatra mandarin (Citrus reticulata) rootstock, grown in a Tavares fine sand (hyperthermic, uncoated, Typic Quartzipsamments) that received various N rates (112, 168, 224, and 280 kg N/ha per year) as either i) broadcast of dry granular form (DGF; four applications/year), or ii) fertigation (FRT; 15 applications/year). Total N in the fruits (mean across 4 years) varied from 82 to 110 and 89 to 111 kg N/ha per year for the DGF and FRT sources, respectively. Proportion of N in the fruits in relation to N applied decreased from 74% to 39% for the DGF and from 80% to 40% for the FRT treatments. High percentage of N removal in the fruits in relation to total N applied at low N rates indicate that trees may be depleting the tree reserve for maintaining fruit production. This was evident, to some extent, by the low leaf N concentration at the low N treatments. Furthermore, canopy density was also lower in the low N trees compared to those that received higher N rates.

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Nutrient Concentrations in Soil Solution in an Alfisol under Grapefruit Production

HortScience ◽

10.21273/hortsci.33.3.498d ◽

1998 ◽

Vol 33 (3) ◽

pp. 498d-498

Author(s):

Z.L. He ◽

A.K. Alva ◽

D.V. Calvert ◽

D.J. Banks ◽

Y.C. Li

Keyword(s):

Soil Solution ◽

Fine Sand ◽

Drainage Water ◽

Tree Canopy ◽

Nutrient Concentrations ◽

Sour Orange ◽

Parallel Study ◽

Ph Measurements ◽

The Mean ◽

N Rates

A field experiment was conducted in a Riviera fine sand (Alfisol) with 25-year-old `White Marsh' grapefruit trees on Sour orange rootstock to monitor the downward transport of nutrients from fertilization practices. Fertilizer was applied as either dry granular broadcast (three applications/year) or fertigation (15 applications/year) at N rates of 56, 112, 168, and 336 kg/ha per year using a N:P:K blend (1.0:0.17:1.0). Soil solution was sampled bi-weekly from suction lysimeters, installed under the tree canopy, about 120 cm from the tree trunk, at two depths representing above (120 cm) and below (180 cm) the hard pan. The concentrations of K, Ca, and Mg were greater at the 180- than at 120-cm depth, whereas, the converse was true with respect to the concentration of P in soil solution. Over a 2-year period, the mean concentrations of P and K varied from 0.031-0.976 and 150-250 mg·L–1, respectively. Increased rate of fertilization also appeared to increase the concentrations of Ca and Mg in the soil solution. This could be due to effects of slight acidification of the soil with increased rates of ammonium form of N. A parallel study on pH measurements has shown evidence of soil acidification, under the tree canopy, with increased rates of ammonium fertilization. In a bedded grove, the soil solution above the hard pan is likely to seep into the water furrow, which is discharged into the drainage water.

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Laboratory investigation of pullout behavior of strengthened geogrid with concrete pieces in fine sand

Innovative Infrastructure Solutions ◽

10.1007/s41062-021-00575-0 ◽

2021 ◽

Vol 6 (4) ◽

Author(s):

Alireza Beyranvand ◽

Seyed Hamid Lajevardi ◽

Mahmoud Ghazavi ◽

Seyed Mohammad Mirhosseini

Keyword(s):

Laboratory Investigation ◽

Fine Sand

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Laboratory Tests on Engineering Properties of Wind-Blown Sand

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.170-173.706 ◽

2012 ◽

Vol 170-173 ◽

pp. 706-709

Author(s):

Zhao Lin Jia ◽

Shu Wang Yan ◽

Zhi Liang Huo

Keyword(s):

Water Content ◽

Laboratory Tests ◽

Fine Sand ◽

Engineering Properties ◽

Grain Composition ◽

Factors Affecting ◽

Compaction Curve ◽

Main Factors ◽

Dry And Wet Conditions ◽

Compaction Properties

By means of laboratory tests and theoretical calculation, the physical, mechanical properties and compaction mechanism of the wind-blown sand are studied to deal with the problem of how to use the wind-blown sand as roadbed materials. It is revealed that water content doesn’t affect the compressibility and the shear strength of the wind-blown sand obviously and the wind-blown sand can be compacted both in dry and wet conditions. The compaction curve of the ordinary fine sand is consistent with that of wind-blown sand and the main factors affecting the compaction properties are the grain composition, water content and compaction work.

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Specifications and testing of self-consolidating mortar designated for annular space grouting

Canadian Journal of Civil Engineering ◽

10.1139/l11-011 ◽

2011 ◽

Vol 38 (4) ◽

pp. 422-432 ◽

Cited By ~ 1

Author(s):

Soo-Duck Hwang ◽

Kamal H. Khayat ◽

Richard Morin

Keyword(s):

High Stability ◽

Fine Sand ◽

Underground Water ◽

Experimental Program ◽

Testing Protocol ◽

Slump Flow ◽

Nominal Size ◽

Repair Mortars ◽

Passing Ability ◽

Good Filling

An experimental program was undertaken to evaluate the performance of self-consolidating mortar designed for filling small annular spaces for the rehabilitation of underground water line or sewage pipelines. The study also intended to establish a testing protocol to validate the workability of repair grout. All the investigated mixtures had good filling and passing ability with adequate retention of workability over 3 h. The repair mortars exhibited high stability with bleeding lower than 0.3% compared to 3% bleeding in the case of the reference neat cement grout. The reference grout had a lower plastic viscosity and higher slump flow values than the sanded repair grouts. A V-funnel with 30 mm × 30 mm overture and a flow cone with 12.7 mm overture are recommended for mortar made with concrete sand with a 5 mm nominal size and micro mortar with fine sand with a nominal size up to 3 mm, respectively.

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Using of Microsilica for Strength Improvement of Fiber Reinforced Cementitious Surface Compounds

ISRN Materials Science ◽

10.1155/2013/173587 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7

Author(s):

S. S. Shebl ◽

Ibrahim S. Khalil ◽

H. Shoukry

Keyword(s):

Date Palm ◽

Fine Sand ◽

Structural Performance ◽

Polypropylene Fibers ◽

Hydration Products ◽

Fiber Reinforced ◽

Surface Compounds ◽

Extension Work ◽

Strength Improvement

This study represents an extension work to investigate the role of ultra fine sand (UFS) in enhancing the mechanical properties of fiber reinforced cementitious compounds. The micro-structural origins were identified by scanning electron microscope (SEM). About 50% of UFS had a diameter of less than 20 μm. Ordinary Portland Cement (OPC) was partially substituted by UFS at 3, 5, 7 and 10% by weight of binder. It was found that as UFS loadings increase, the flexural, compressive, and tensile strengths increased up to about 5% UFS loading by 12.9, 15.7 and 30.1%, respectively, thereafter, a decrease in these properties was observed. This can be attributed to the pozzolanic effect besides the filling effect of UFS resulting in enhancing the interfacial bonds between the sand grains and hydration products that makes the paste more homogeneous and dense. The effect of both short natural and artificial fiber loadings on the structural performance of compounds was also studied. Loadings of 2%, by weight, of short natural date palm leaves’ midribs fibers (DP) and artificial polypropylene fibers (PP) were added to the 5% UFS blended mix. An increase in both flexural and tensile strength was achieved, while a decrease in the compressive strength was observed.

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The Metazoan Meiofauna in Its Biogeochemical Environment: The Case of an Antarctic Coastal Sediment

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400041539 ◽

1998 ◽

Vol 78 (2) ◽

pp. 411-434 ◽

Cited By ~ 15

Author(s):

S. Vanhove ◽

H.J. Lee ◽

M. Beghyn ◽

D. Van Gansbeke ◽

S. Brockington ◽

...

Keyword(s):

Organic Matter ◽

Standing Stock ◽

Austral Summer ◽

Fine Sand ◽

Coastal Sediment ◽

Feeding Guild ◽

Fresh Organic Matter ◽

Benthic Environment ◽

Metazoan Meiofauna ◽

Deposit Feeding

The metazoan meiobenthos was investigated in an Antarctic coastal sediment (Factory Cove, Signy Island, Antarctica). The fine sands contained much higher abundances compared to major sublittoral sediments worldwide. Classified second after Narrangansett Bay (North Atlantic) they reached numbers of 13 × 106ind m-2. The meiofauna was highly abundant in the surface layers, but densities decreased sharply below 2 cm. Vertical profiles mirrored steep gradients of microbiota, chloropigments and organic matter and were coincident with chemical stratification. Spatial patchiness manifested especially in the surface layer. Nematodes dominated (up to 90%), andAponema, Chromctdorita, Diplolaimella, Daptonema, MicrolaimusandNeochromadoraconstituted almost the entire community. Overall, the nematode fauna showed a strong similarity with fine sand communities elsewhere. The dominant trophic strategies were epistrarum and non-selective deposit feeding, but the applied classification for feeding guild structure of the nematodes of Factory Cove is discussed. High standing stock, low diversity and shallow depth distribution may have occurred because of the high nutritive (chlorophyll exceeded lOOOmgm-2and constituted almost 50% of the organic pool) and reductive character of the benthic environment. These observations must have originated from the substantial input of fresh organic matter from phytoplankton and microphytobenthic production, typical for an Antarctic coastal ecosystem during the austral summer.

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