Effect of Compaction Pressure on the Physical, Mechanical, and Tribological Behavior of Compacted Crab Shell Particles Prepared Using Uniaxial Compaction Route

Considering the unique characteristics of rare earth elements (REEs), the presence of REEs beyond specific limits will adversely affect the environment and it can be employed as a powerful probe for investigating hydrogeochemical processes. This requires sensitive determination of REEs in natural seawater. A matrix separation and pre-concentration technique using the mini-column packed with crab shell particles (CSPs) by inductively coupled plasma mass spectrometry (ICP-MS) as a means of determination has been developed. The aim of the proposed method was to simultaneously determine 16 REEs (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) at trace or ultra-trace concentrations in seawater. The biosorption capacity of CSPs was found to achieve 1.246–1.250 mg g−1 for all elements. In order to optimize performance of the method, the effects of analytical parameters concerning oscillation time, solution pH, salt concentration and eluent concentration were explored. Under the optimal conditions, the detection limits of REEs ranged 0.0006–0.0088 μg L−1, and relative standard deviations (n = 7) varied between 0.55 and 1.39%. The accuracy of developed method was evidenced by applying it to the analysis of REEs in seawater samples, with the overall recoveries at a level of 95.3 and 104.4%. Together, this work provides a promising and cost-effective CSPs-based pretreatment approach for REEs detection in sea environment.

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Biosorption of copper(II) and cobalt(II) from aqueous solutions by crab shell particles

Bioresource Technology ◽

10.1016/j.biortech.2005.07.001 ◽

2006 ◽

Vol 97 (12) ◽

pp. 1411-1419 ◽

Cited By ~ 207

Author(s):

K. Vijayaraghavan ◽

K. Palanivelu ◽

M. Velan

Keyword(s):

Aqueous Solutions ◽

Crab Shell ◽

Shell Particles

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Effects of Uniaxial Compaction Pressure on the Dielectric Properties ofBaTiO3/Polyvinylidene Fluoride Composites

Japanese Journal of Applied Physics ◽

10.1143/jjap.33.3991 ◽

1994 ◽

Vol 33 (Part 1, No. 7A) ◽

pp. 3991-3995 ◽

Cited By ~ 7

Author(s):

Hsing-I Hsiang ◽

Fu-Su Yen

Keyword(s):

Dielectric Properties ◽

Polyvinylidene Fluoride ◽

Compaction Pressure ◽

Uniaxial Compaction

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Characterization of Mechanical Property Distributions on Tablet Surfaces

Pharmaceutics ◽

10.3390/pharmaceutics10040184 ◽

2018 ◽

Vol 10 (4) ◽

pp. 184 ◽

Cited By ~ 3

Author(s):

Ramon Cabiscol ◽

Jan Finke ◽

Harald Zetzener ◽

Arno Kwade

Keyword(s):

Surface Area ◽

Microcrystalline Cellulose ◽

Elastic Recovery ◽

Compaction Pressure ◽

Plastic Behavior ◽

Brittle Behavior ◽

Stiffness Anisotropy ◽

Deformation Behaviors ◽

Uniaxial Compaction ◽

Local Stiffness

Powder densification through uniaxial compaction is governed by a number of simultaneous processes taking place on a reduced time as the result of the stress gradients within the packing, as well as the frictional and adhesive forces between the powder and the die walls. As a result of that, a density and stiffness anisotropy is developed across the axial and radial directions. In this study, microindentation has been applied to assess and quantify the variation of the module of elasticity ( E m o d ) throughout the surface of cylindrical tablets. A representative set of deformation behaviors was analyzed by pharmaceutical excipients ranging from soft/plastic behavior (microcrystalline cellulose) over medium (lactose) to hard/brittle behavior (calcium phosphate) for different compaction pressures. The results of the local stiffness distribution over tablet faces depicted a linear and directly proportional tendency between a solid fraction and E m o d for the upper and lower faces, as well as remarkable stiffness anisotropy between the axial and radial directions of compaction. The highest extent of the stiffness anisotropy that was found for ductile grades of microcrystalline cellulose (MCC) in comparison with brittle powders has been attributed to the dual phenomena of overall elastic recovery and Poisson’s effect on the relaxation kinetics. As a reinforcement of this analysis, the evolution of the specific surface area elucidated the respective densification mechanism and its implementations toward anisotropy. For ductile excipients, the increase in the contact surface area as well as the reduction and closing of interstitial pores explain the reduction of surface area with increasing compaction pressure. For brittle powders, densification evolves through fragmentation and the subsequent filling of voids.

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Determination of the efficiency and removal mechanism of cobalt by crab shell particles

Journal of Chemical Technology & Biotechnology ◽

10.1002/jctb.1139 ◽

2004 ◽

Vol 79 (12) ◽

pp. 1388-1394 ◽

Cited By ~ 23

Author(s):

Moo-Yeal Lee ◽

Kyung-Jin Hong ◽

Toshio Kajiuchi ◽

Ji-Won Yang

Keyword(s):

Removal Mechanism ◽

Crab Shell ◽

Shell Particles

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Compaction Characteristics of Tungsten Carbide Based Self-Lubricant Cutting Tool Material

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.87 ◽

2014 ◽

Vol 592-594 ◽

pp. 87-91

Author(s):

A. Muthuraja ◽

S. Senthilvelan

Keyword(s):

Tungsten Carbide ◽

Relative Density ◽

Solid Lubricant ◽

Cutting Tool ◽

Compaction Pressure ◽

Tool Material ◽

Work Sample ◽

Hardness Tester ◽

Sample Density ◽

Uniaxial Compaction

In this study, an attempt has been made to develop solid lubricant cutting tool material with the aid of powder metallurgy technique. Chosen tungsten carbide, cobalt and calcium fluoride were milled in the planetary ball milling, followed by uniaxial compaction and sintering in a tube furnace. Materials were milled at various hours of milling and compaction pressure to understand the effect of relative density and hardness of sintered specimens. It is found that the relative density of compacted and sintered specimens found to increase with the compaction pressure but decreased with milling time after particular time. From the investigation, 40 hr of milling and 400 MPa compaction pressure found to be suitable for the development of proposed material. In this work, sample density was measured by the Archimedes’ method and hardness was measured by Rockwell hardness tester.

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