Consolidation of Sand by Alkaline Silicate Solution

2010 ◽  
Vol 68 ◽  
pp. 84-89
Author(s):  
Sandrine Lucas ◽  
Monique Tohoué Tognonvi ◽  
Julien Soro ◽  
Sylvie Rossignol ◽  
Jean Louis Gelet
Keyword(s):  
Electron Microscopy ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Strength Test ◽  
Gravimetric Analysis ◽  
Compressive Strength Test ◽  
Concentration Of Solutions ◽  
Sand Particles ◽  
Increasing Temperature ◽  
Scanning Electron

Progress of fuse technology to reduce cost and to protect environment requires the understanding of physicochemical phenomena that govern the consolidation of the sand with alkaline silicate solution. In this context, this work concerns the agglomeration behaviours of sand with alkaline silicate solution. The effects of sand particles size and concentration of solutions are investigated at various temperatures. The main objective is to understand the interactions between sand and this alkaline solution during the impregnation of sand with sodium silicate solution and the drying leading to the consolidated materials. Various investigations were performed, thermogravimetrical and differential thermal analysis (TG/DTA), gravimetric analysis of wet sample, scanning electron microscopy (SEM) and compressive strength test on dry samples. The results show that agglomeration is affected by silica grains size distribution and temperature. Bonds strength between the grains increase with decreasing grain size and increasing temperature.

The Effect of Different Silica Compositions to the Properties of Silica Foam Fabricated Using Slurry Method

2017 ◽  
Vol 888 ◽  
pp. 121-125 ◽  
Author(s):  
Syazwani Baharom ◽  
Sufizar Ahmad ◽  
Muhamad Izranuddin Mohd Ramli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Compressive Strength ◽  
Polyethylene Glycol ◽  
Morphological Analysis ◽  
Strength Test ◽  
Distilled Water ◽  
Compressive Strength Test ◽  
Slurry Method ◽  
Scanning Electron

Silica foams with 50% – 70% porosity have been developed by mixing silica powder, polyethylene glycol (PEG) and carboxymethyl cellulose (CMC) into distilled water to make slurry. Polyurethane foam (PU) as the template is immersed into the slurry with 45 wt.%, 50 wt.% and 55 wt.%. of silica composition and finally sintered at 1100°C, 1200°C, 1300°C and 1400°C. Several tests which are morphological analysis, porosity and density test, and compressive strength test are compulsory to determine the physical and mechanical of the silica foam. The morphology of the foam has been observed using Scanning Electron Microscopy (SEM) and the result of pore size distribution is in the range of 255.91 μm to 489.14 μm. The porosity and density obtained from the porosity and density test was 50%-73.66% and 0.5499 g/cm³ up to 0.9757 g/cm³, respectively. Meanwhile, the compressive strength of sintered silica foam obtained is 0.01471 N/mm² up to 0.1467 N/mm².

A Study on Relationship between Porosity and Compressive Strength for Geopolymer Paste

2013 ◽  
Vol 594-595 ◽  
pp. 1112-1116 ◽  
Author(s):  
Z.F. Farhana ◽  
H. Kamarudin ◽  
Azmi Rahmat ◽  
A.M. Mustafa Al Bakri
Keyword(s):  
Compressive Strength ◽  
Sodium Hydroxide Solution ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Pulse Velocity ◽  
Strength Test ◽  
Compressive Strength Test ◽  
Alkaline Activator ◽  
The Relationship ◽  
Geopolymer Paste

This paper presents a study on the relationship between porosity and compressive strength for geopolymer paste. In this research, geopolymer paste was made from fly ash class F based geopolymer mixed with alkaline activator; sodium hydroxide solution and sodium silicate solution. Twelve mixes were cast in 50mm x 50mm x 50mm moulds and the samples were cured for 24 hrs at 60 °C in the oven. The samples were examined after 7, 14, 28 and 90 days in terms of porosity test, pulse velocity test and compressive strength test. It was concluded that the sample at day 90 had the highest compressive strength of 56.50 N/mm2had porosity 3.77%. Thus, the sample with lowest porosity had highest pulse velocity 3303 m/s during ultrasonic testing with lowest transmission time 15.17 μs. Keywords: porosity, compression strength, geopolymer, pulse velocity

Sausage Casings as a Model for Attachment of Salmonella to Meat

1993 ◽  
Vol 56 (5) ◽  
pp. 390-394 ◽  
Author(s):  
ISABEL WALLS ◽  
PETER H. COOKE ◽  
ROBERT C. BENEDICT ◽  
ROBERT L. BUCHANAN
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bacterial Attachment ◽  
Bacterial Cells ◽  
Inoculum Level ◽  
Plate Counts ◽  
Increasing Temperature ◽  
Convenient Model ◽  
Sausage Casing ◽  
Scanning Electron

Artificial sausage casings were used as a model for studying bacterial attachment to meat connective tissue. Sausage casings of known mass were exposed to suspensions of Salmonella typhimurium in 0.15 M NaCl under various time, temperature, and inoculum level regimes, then washed to remove unattached bacteria. Attached bacterial cells were enumerated using both plate counts and scanning electron microscopy. Bacterial cells attached to sausage casing surfaces within 1 min of incubation. Numbers of attached cells increased with increasing temperature and inoculum levels and with time. Rates of attachment of S. typhimurium to sausage casings were comparable with those reported for attachment to meat surfaces. Sausage casings appear to be a convenient model for examining mechanisms of bacterial attachment to meats.

scholarly journals Structural and thermoelectric properties of the Pr2Zr2O7 compound

2019 ◽  
pp. 4-9
Author(s):  
Adolfo Quiroz-Rodríguez ◽  
Cesia Guarneros-Aguilar ◽  
Ricardo Agustin-Serrano
Keyword(s):  
Electron Microscopy ◽  
Thermal Conductivity ◽  
Thermoelectric Properties ◽  
Crystal Size ◽  
Ambient Pressure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Increasing Temperature ◽  
Thermal Stability Of ◽  
Scanning Electron

In this research, it is presented a detailed study of the structural and thermoelectric properties of the pyrochlore zirconium Pr2Zr2O7 compound prepared by solid-state reaction (SSR) in air at ambient pressure. The synthesized sample was characterized using powder X-ray diffraction. The thermal stability of the thermoelectric compound (TE) Pr2Zr2O7 was tested by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Scanning electron microscopy shows that the crystal size varies between 0.69 and 2.81μm. Electrical conductivity (\sigma) of the sample calcined at 1400 °C presented values increase irregularly with the increasing temperature from 0.001 to 0.018 S cm-1 as expected in a semiconductor material. The thermal conductivity is lower than 0.44 - 775 W m-1 K-1 which is quite anomalous in comparison with the thermal conductivity of other oxides.

scholarly journals Structuration and Fabrication of Sensors Based on LTCC (Low Temperature Co-Fired Ceramic) Technology

2007 ◽  
Vol 336-338 ◽  
pp. 1849-1852 ◽  
Author(s):  
Hansu Birol ◽  
Thomas Maeder ◽  
Caroline Jacq ◽  
Giancarlo Corradini ◽  
Marc Boers ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Considerable Increase ◽  
Thermo Gravimetric Analysis ◽  
Ceramic Technology ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Sensor Performance ◽  
Measuring Sensor ◽  
Selection Of ◽  
Scanning Electron

The purpose of this paper is to demonstrate sensors and structures fabricated using the LTCC technology, which has been addressed and employed increasingly as a smart packaging approach for several applications. The focus will be on inclination and cantilever force sensors and micro-fluidic structures. Motivation for selection of LTCC for these applications in addition to fabrication and structuring of the devices will be explained in details. TGA (thermo-gravimetric analysis), dilatometer analysis, SEM (scanning electron microscopy), electronic equipment for measuring sensor performance will be extensively used for explanation of the results. It will also be shown that, compared to classical thick-film technology on alumina, LTCC allows a considerable increase in sensitivity, and is therefore better suited for the sensing of minute forces and pressures.

Thermal Conductivity of Boron Carbides

1987 ◽  
Vol 97 ◽  
Author(s):  
Marvin Moss
Keyword(s):  
Electron Microscopy ◽  
Thermal Conductivity ◽  
Scanning Electron Microscopy ◽  
Raman Spectroscopy ◽  
Temperature Dependence ◽  
Rutherford Backscattering ◽  
Rutherford Backscattering Spectroscopy ◽  
Theoretical Density ◽  
Increasing Temperature ◽  
Scanning Electron

ABSTRACTThe thermal conductivity, k, of boron carbides of various B/C ratios, two modes of preparation – hot pressed and carbothermic, and two isotopic variants of boron – 11B and normal boron 10.81B, was measured from 300 to 1023 K. The density and composition of the samples were reflected in the magnitude and temperature dependence of k, and were investigated further with scanning electron microscopy, Rutherford backscattering spectroscopy, and Raman spectroscopy. While lower than theoretical density in B4C reduces k, the characteristic monotonic decline of k with increasing temperature is retained. This k-vs.-T behavior distinguishes B4C from material with larger B/C ratios for which the temperature dependence is essentially nil.

The Permanently Bonded Glass Decor from Chemical Precursors

2008 ◽  
Vol 39-40 ◽  
pp. 579-582
Author(s):  
H. Niciu ◽  
Dorel Radu ◽  
C. Onose ◽  
A. Ioncea ◽  
Daniela Niciu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Alkaline Earth ◽  
Earth Metal ◽  
Silicate Solution ◽  
Metal Salts ◽  
Alkaline Earth Metal ◽  
Molar Ratios ◽  
Ink Jet ◽  
Scanning Electron

Alkaline earth metal silicates as well as many polyvalent metals silicates can be obtained through aqueous solutions reactions between an alkaline silicate solution and the solutions of metal salts. The vitrifiation of the oxide compositions, established by the necessary molar ratios for the projected glass, is realised by calculating the concentration of chemical precursors, through their reaction directly on the substrate. The sodium silicate viscosity in aqueous solution and the viscosity of nitrogenated compounds or oxalates necessary in the silicates synthesis is compatible with the necessary viscosity for ink-jet cartridges. The necessary silicates forming reactions were studied directly on the deposition support, so that the functional characteristics of the multicompartment ink-jet cartridges were used. Compositions were realised, in which the colouring effect was obtained with ionic colorants. The vitrifiation and the quality of the obtained thin films were studied through Optical Microscopy and Scanning Electron Microscopy.

scholarly journals Study of Electrical and Thermal Properties of PVA-Nanosilica as A Candidate for Supercapacitor Separators

2021 ◽  
Vol 2110 (1) ◽  
pp. 012012
Author(s):  
N Hidayati ◽  
Munasir
Keyword(s):  
Electron Microscopy ◽  
Thermo Gravimetric Analysis ◽  
Glass Plate ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Two Samples ◽  
Lcr Meter ◽  
Silica Dioxide ◽  
Pva Gel ◽  
Scanning Electron

Abstract Separator in the supercapacitor that separates the cathode from the anode has an important role in a supercapacitor circuit. Polyvinyl Alcohol (PVA) is a substitute for polyolefin which is commonly used as a supercapacitor separator and PVA has more environmentally friendly properties. The addition of silica dioxide nanocomposites is useful for adding thermal stability and electrical insulators. The method used to make the separator is quite simple, namely by casting a PVA gel membrane with nanosilica on a glass plate and drying it at low temperature. PVA membrane with nanosilica variations different precursors are from sand by coprecipitation method and from TEOS. The properties of the two samples were characterized by scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), and LCR meter. Nanosilica derived from sand and from TEOS have no much different characteristic.

scholarly journals Graphene oxide-loaded shortening as an environmentally friendly heat transfer fluid with high thermal conductivity

2017 ◽  
Vol 21 (5) ◽  
pp. 2247-2254
Author(s):  
Thammasit Vongsetskul ◽  
Peeranut Prakulpawong ◽  
Panmanas Sirisomboon ◽  
Jonggol Tantirungrotechai ◽  
Chanasuk Surasit ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Electron Microscopy ◽  
Thermal Conductivity ◽  
Graphene Oxide ◽  
Environmentally Friendly ◽  
High Thermal Conductivity ◽  
Chemical Degradation ◽  
Heat Transfer Fluid ◽  
Increasing Temperature ◽  
Scanning Electron

Graphene oxide-loaded shortening (GOS), an environmentally friendly heat transfer fluid with high thermal conductivity, was successfully prepared by mixing graphene oxide (GO) with a shortening. Scanning electron microscopy revealed that GO particles, prepared by the modified Hummer?s method, dispersed well in the shortening. In addition, the latent heat of GOS decreased while their viscosity and thermal conductivity increased with increasing the amount of loaded GO. The thermal conductivity of the GOS with 4% GO was higher than that of pure shortening of ca. three times, from 0.1751 to 0.6022 W/mK, and increased with increasing temperature. The GOS started to be degraded at ca. 360?C. After being heated and cooled at 100?C for 100 cycles, its viscosity slightly decreased and no chemical degradation was observed. Therefore, the prepared GOS is potentially used as environmentally friendly heat transfer fluid at high temperature.

Synthesis, characterisation and tribological evaluation of surface-capped molybdenum sulphide nanoparticles as efficient antiwear bio-based lubricant additives

2017 ◽  
Vol 69 (3) ◽  
pp. 378-386 ◽  
Author(s):  
Sharul Hafiq Roslan ◽  
Sharifah Bee Abd Hamid ◽  
Nurin Wahidah Mohd Zulkifli
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Wear Scar ◽  
Gravimetric Analysis ◽  
Content Type ◽  
X Ray ◽  
Lubricant Oil ◽  
Wear Reduction ◽  
Molybdenum Sulphide ◽  
Scanning Electron

Purpose The purpose of this study is to synthesise and characterise surface-capped molybdenum sulphide (SCMS) nanoparticles using the solvothermal method and to investigate their tribological behaviour towards friction improver and wear reduction for bio-based lubricant oil additives. Design/methodology/approach The design of the experiment was to use freshly prepared molybdenum (II) acetate, thioacetamide, fatty acid and hexane as the solvent inside an autoclave vessel which is heated at high temperature and pressure. Various types of fatty acids were used as the capping agent, such as caproic, lauric, stearic and oleic acid. The SCMS nanoparticles formed were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffractometry, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and thermal gravimetric analysis. These nanoadditives were then blended into pentaerythrityl tetracaprylate/caprate ester at 0.05 Wt.% concentration. The formulated bio-based lubricant oil samples were tested for viscosity, viscosity index (VI) and density based on standard method ASTM D445 and ASTM D2270. A four-ball test was carried out for determination of coefficient of friction and wear scar diameter. The wear scar formed on the surface of the ball bearing was analysed using scanning electron microscopy. Findings The characterisation results showed that SCMS nanoparticles were successfully formed with amorphous ball-like structure, and the presence of the capping layer surrounding the nanoparticles was confirmed. Then, the formulated bio-based lubricant oil with addition of nanoadditives displays improved tribological properties in term of VI, antifriction and wear reduction. Originality/value This research provides a synthesis method of producing SCMS nanoparticles using the organomolybdenum complex as the chemical precursor through the solvothermal reaction approach. Besides that, it also gives an alternative antifriction and antiwear nanoadditive for formulation of the bio-based lubricant oil.

Sign in / Sign up

Export Citation Format

Share Document