scholarly journals Fabrication of Polycrystalline Cubic Boron Nitride/Metal Composite Particles by Surface Metallization Followed by Electroless Deposition Technique

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7906
Author(s):  
Walid Mohamed Daoush ◽  
Turki Saad Alkhuraiji ◽  
Abdulrahman Dohymish Alshammri
Keyword(s):  
Electroless Deposition ◽  
Energy Dispersive Spectrometer ◽  
Metallic Copper ◽  
Thermo Gravimetric Analysis ◽  
Composite Particles ◽  
Coating Process ◽  
Gravimetric Analysis ◽  
Metal Composite ◽  
Composite Powders ◽  
Copper Composite

Polycrystalline cBN/copper composite abrasive particles were prepared by an electroless powder coating process. Ti metallization and tin/silver metallization techniques were used to improve the coating process by depositing an autocatalytic metallic layer on the surface of the cBN particles. Metallized, as well as un-metallized, cBN particles were further coated by copper using electroless deposition. Electroless copper coating of un-metallized and metallized cBN particles by 90 wt.% of copper were achieved. The surface morphology, the composition and the crystalline phase identifications of the metallized cBN particles, as well as the 10 wt.% cBN /copper composite powders, were investigated by field emission scanning electron microscopy, an energy-dispersive spectrometer and an X-ray diffractometer. The results show that the surface of the Ti metalized and tin/Ag-metallized cBN particles were covered by the nanosized Ti or Ag layer, respectively, which enhanced the deposition of the copper during the electroless deposition bath. The results also showed that the deposited layer on the metallized cBN particles was composed mainly of metallic copper. The produced 10 wt.% cBN/copper composite particles also underwent thermo-gravimetric analysis to investigate its stability at high temperature. It was revealed that the Ti-metallized cBN/copper composite powder has higher stability at 800 °C under the environmental conditions than the tin/silver-metallized and the un-metallized cBN/copper composite particles, respectively.

Tribological and thermomechanical analysis of CaO (quicklime) particulates filled ZA-27 alloy composites for bearing application

2015 ◽  
Vol 232 (1) ◽  
pp. 20-34 ◽  
Author(s):  
Swati Gangwar ◽  
Amar Patnaik ◽  
IK Bhat
Keyword(s):  
Wear Rate ◽  
Normal Load ◽  
Energy Dispersive Spectrometer ◽  
Thermo Gravimetric Analysis ◽  
Research Work ◽  
Surface Profile ◽  
Specific Wear Rate ◽  
Gravimetric Analysis ◽  
Load Range ◽  
Environment Temperature

This research work investigates friction and wears behaviour of CaO filler / particulate reinforced ZA-27 alloy composites. Pin-on-disk tribometer confining to ASTM G 99 standard with EN-31 hardened steel disc was used to simulate the tribological performance experimentally. The tribological parameters were evaluated over a normal load range of 5–45 N, sliding velocity of 1.047–5.235 m/s., sliding distance of 500–2500 m, environment temperature of 25–45℃ and filler content range of 0–10 wt%. The various alloy composites were fabricated under vacuum environment by high-temperature gravity casting technique. The steady-state specific wear rate and coefficient of friction were evaluated under different boundary conditions and thereafter Taguchi design of experiment methodology was adopted to compute the experimental specific wear rate of the proposed alloy composites. The dynamic mechanical analysis and thermo-gravimetric analysis study were also performed in order to observe the thermal characteristics of the composites at higher temperature. Finally, the surface morphology of the worn samples was performed using field-emission scanning electron microscope to understand the wear mechanism prevailed at rubbing surfaces and then atomic force microscopy analysis was studied to evaluate the surface profile of the worn sample. At the end, energy-dispersive spectrometer analysis was also performed to find out the elemental compositions of the worn alloy composites.

Effect of boron-nitrogen modified soybean oil additive on biodegradability, anti-oxidation property, and lubricity of rapeseed oil

2019 ◽  
Vol 234 (2) ◽  
pp. 282-291 ◽  
Author(s):  
Ping Liu ◽  
Xin Wang ◽  
Jiang Wu ◽  
Wang Lin ◽  
Yanhan Feng ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Soybean Oil ◽  
Rapeseed Oil ◽  
Energy Dispersive Spectrometer ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Modified Soybean Oil ◽  
Wear And Friction ◽  
Friction Reducing ◽  
Boron Nitrogen

Two novel boron-nitrogen modified soybean oil additives with different length of chain structures (abbreviated as BNS1 and BNS2) were synthesized. The thermal stability of BNS1 and BNS2 was evaluated by thermo-gravimetric analysis. The effect of the as-synthesized additives on the biodegradability, anti-oxidation property, and lubricity in rapeseed oil was evaluated by respective standard method. Moreover, the morphology and tribochemical characteristics of the worn surfaces were examined by scanning electron microscope assembled with energy dispersive spectrometer. The results indicated that BNS1 and BNS2 both possess good thermal stability; BNS1 slightly impairs the biodegradability of rapeseed oil, but BNS2 facilitates the biodegradability of rapeseed oil. BNS1 and BNS2 could improve the anti-wear and friction-reducing performance of the rapeseed oil, but BNS1 exhibited better anti-wear ability as compared to that of BNS2, BNS2 exhibited better anti-wear ability in reducing friction coefficients as compared to that of BNS1. The enhanced anti-wear and friction-reducing abilities of rapeseed oil were ascribed to the formation of a composite boundary lubrication film due to the strong adsorption of BNS1 or BNS2 and rapeseed oil onto the lubricated surfaces and their tribochemical reactions with metal surfaces. BNS1 and BNS2 could both facilitate the anti-oxidation properties of the rapeseed oil.

Electro-mechanical and thermal characteristics of silver-electroded ionic polymer–metal composite actuator

2011 ◽  
Vol 226 (6) ◽  
pp. 1427-1436 ◽  
Author(s):  
D K Biswal ◽  
D Bandopadhya ◽  
S K Dwivedy
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Thermal Characteristics ◽  
Experimental Investigations ◽  
Gravimetric Analysis ◽  
Metal Composite ◽  
Ionic Polymer Metal Composite ◽  
Scanning Calorimetry ◽  
Ionic Polymer ◽  
Base Polymer ◽  
Polymer Metal

The proposed work is in line with the evaluation of electro-mechanical and thermal characteristics of silver-electroded ionic polymer–metal composite (IPMC). IPMCs are fabricated first using Nafion-117 as base polymer and non-precious metal silver as surface electrode by chemical decomposition method. Several testings are performed on fabricated IPMC to evaluate its thermo-mechanical and micro-structural properties. The characteristics of the electrode layer and deposited particles on IPMC surface are studied using scanning electron microscope. The bending experiment of the actuator is conducted by applying direct current potential and the tip displacement measured. Thermo-gravimetric analysis and differential scanning calorimetry test are carried out, and thermal stability of the actuator is investigated. The crystal structure of IPMC is investigated by X-ray diffraction analysis. Micro-tensile test of the specimen is carried out to ascertain the stress–strain relationship and comparison is made with the base polymer, Nafion. The experimental investigations, characterization, and performance of the IPMC demonstrate its effectiveness to be used as actuator and artificial muscle materials.

Metal-Based Iodine Bearing Materials Prepared by Mechanical Milling

2015 ◽  
Vol 1758 ◽  
Author(s):  
Song Wang ◽  
Amy Corcoran ◽  
Victoria Leybova ◽  
Edward L. Dreizin
Keyword(s):  
Mechanical Milling ◽  
Thermo Gravimetric Analysis ◽  
Combustion Products ◽  
Biological Weapons ◽  
Gravimetric Analysis ◽  
Composite Powders ◽  
Two Stage ◽  
Thermo Gravimetric ◽  
Constant Rate ◽  
Bearing Materials

ABSTRACTRecent research has demonstrated that ternary aluminum-boron-iodine (Al-B-I2) materials prepared by mechanical milling are effective in generating biocidal combustion products. Such reactive materials are of interest for the munitions aimed to defeat stockpiles of biological weapons. In this research, ternary Mg∙B∙I2 composites were synthesized using two-stage milling. The first stage consisted of a binary B∙I2 powder prepared by mechanical milling, followed by addition of magnesium for iodine stabilization. Specific compositions for each ternary material were varied. Stability of the samples was assessed by their heating in argon at a constant rate using Thermo Gravimetric Analysis (TGA) and observing weight loss. Oxidation of the prepared powders was also studied by TGA. Ternary Mg∙B∙I2 composite powders prepared by two-stage milling were more stable than any of the previously prepared iodine-bearing materials with the same concentration of iodine (20 wt %). Particle size distributions were measured using low-angle laser light scattering. Powders were ignited using in an air-acetylene flame and in a constant volume explosion apparatus. Particle burn times and temperatures were measured optically. Substantially longer burn times and lower temperatures were observed for the prepared materials compared to the reference pure Mg powder.

Synthesis of Smart Mesoporous Materials

2003 ◽  
Vol 775 ◽  
Author(s):  
G.V.Rama Rao ◽  
Qiang Fu ◽  
Linnea K. Ista ◽  
Huifang Xu ◽  
S. Balamurugan ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Mesoporous Materials ◽  
Fluorescent Dyes ◽  
Thermo Gravimetric Analysis ◽  
Molecular Transport ◽  
Solute Diffusion ◽  
Gravimetric Analysis ◽  
Stimuli Responsive ◽  
Porous Network ◽  
Hybrid Mesoporous Materials

AbstractThis study details development of hybrid mesoporous materials in which molecular transport through mesopores can be precisely controlled and reversibly modulated. Mesoporous silica materials formed by surfactant templating were modified by surface initiated atom transfer radical polymerization of poly(N-isopropyl acrylamide) (PNIPAAm) a stimuli responsive polymer (SRP) within the porous network. Thermo gravimetric analysis and FTIR spectroscopy were used to confirm the presence of PNIPAAm on the silica surface. Nitrogen porosimetry, transmission electron microscopy and X-ray diffraction analyses confirmed that polymerization occurred uniformly within the porous network. Uptake and release of fluorescent dyes from the particles was monitored by spectrofluorimetry and scanning laser confocal microscopy. Results suggest that the presence of PNIPAAm, a SRP, in the porous network can be used to modulate the transport of aqueous solutes. At low temperature, (e.g., room temperature) the PNIPAAm is hydrated and extended and inhibits transport of analytes; at higher temperatures (e.g., 50°C) it is hydrophobic and is collapsed within the pore network, thus allowing solute diffusion into or out of the mesoporous silica. The transition form hydrophilic to hydrophobic state on polymer grafted mesoporous membranes was determined by contact angle measurements. This work has implications for the development of materials for the selective control of transport of molecular solutes in a variety of applications.

Coordination Compounds of Some 3d-Transition Metal Ions with N1-[4-(4-bromo-phenylsulfonyl)-benzoyl]-N4-(4-methoxyphenyl)- thiosemicarbazide

2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Madalina Angelusiu ◽  
Maria Negoiu ◽  
Stefania-Felicia Barbuceanu ◽  
Tudor Rosu
Keyword(s):  
Coordination Compounds ◽  
Magnetic Moments ◽  
Thermo Gravimetric Analysis ◽  
Electronic Spectroscopy ◽  
Transition Metal Ions ◽  
Synthesis And Characterization ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
New Compounds

The paper presents the synthesis and characterization of Cu(II), Co(II), Ni(II), Cd(II), Zn(II) and Hg(II) complexes with N1-[4-(4-bromo-phenylsulfonyl)-benzoyl]-N4-(4-methoxyphenyl)-thiosemicarbazide. The new compounds were characterized by IR, EPR, electronic spectroscopy, magnetic moments, thermo-gravimetric analysis and elemental analysis.

Collagen And Carbon-Ferrous Nanoparticles Used As A Green Energy Composite Material For Energy Storage Devices

2020 ◽  
Vol 13 ◽  
Author(s):  
Inbasekaran S. ◽  
G. Thiyagarajan ◽  
Ramesh C. Panda ◽  
S. Sankar
Keyword(s):  
Composite Material ◽  
Thermo Gravimetric Analysis ◽  
Value Added ◽  
Green Energy ◽  
Nano Particles ◽  
Hydroxyl Group ◽  
Gravimetric Analysis ◽  
Circuit Testing ◽  
Battery Cell ◽  
Dc Voltage

Background:: Chrome shavings, a bioactive material, are generated from tannery as waste material. These chrome shaving can be used for the preparation of many value-added products. Objective:: One such attempt is made to use these chrome shaving wastes as a composite bio-battery to produce DC voltage, an alternate green energy source and cleaner technology. Methods:: Chrome shavings are hydrolyzed to make collagen paste and mixed with the ferrous nanoparticles of Moringa oleifera leaves and Carbon nanoparticles of Onion peels to form electrolyte paste as base. Then, the electrolyte base was added to the aluminum paste and conducting gel, and mixed well to form composite material for bio-battery. Results:: The composite material of bio-battery has been characterized using Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA). Series and parallel circuit testing were done using Copper and Zinc electrodes or Carbon and Zinc electrodes as the battery terminals in the electrolyte paste. The surface area of these electrodes needs standardization from bench to pilot scale. The power generated, for an AA battery size, using a single bio-battery cell has produced a DC voltage of 1.5 V; current of 900 mA. Circuit testing on 1 ml of 80 well-cells connected in series has produced DC output of 18 V and 1100 mA whereas 48 V and 1500 mA were obtained from a series-parallel connection. Conclusion:: The glass transition temperature (Tg) of electrolyte of the bio-battery at 53°C indicates that, at this temperature, all the substances present in the bio-battery are well spread and contributing consistently to the electrolyte activity where Fe-C-Nano-Particles were able to form strong chemical bonds on the flanking hydroxyl group sites of the Collagen leading to reduced mobility of polymers and increase Tg. The results instigate promising trends for commercial exploitation of this composite for bio-battery production.

In-situ stabilization of silver nanoparticles in polymer hydrogels for enhanced catalytic reduction of macro and micro pollutants

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Luqman Ali Shah ◽  
Rida Javed ◽  
Mohammad Siddiq ◽  
Iram BiBi ◽  
Ishrat Jamil ◽  
...  
Keyword(s):  
Catalytic Reduction ◽  
Thermo Gravimetric Analysis ◽  
Activation Parameters ◽  
Reduction Reaction ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
In Situ Stabilization ◽  
Hybrid Hydrogels ◽  
Kinetics Of

AbstractThe in-situ stabilization of Ag nanoparticles is carried out by the use of reducing agent and synthesized three different types of hydrogen (anionic, cationic, and neutral) template. The morphology, constitution and thermal stability of the synthesized pure and Ag-entrapped hybrid hydrogels were efficiently confirmed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). The prepared hybrid hydrogels were used in the decolorization of methylene blue (MB) and azo dyes congo red (CR), methyl Orange (MO), and reduction of 4-nitrophenol (4-NP) and nitrobenzene (NB) by an electron donor NaBH4. The kinetics of the reduction reaction was also assessed to determine the activation parameters. The hybrid hydrogen catalysts were recovered by filtration and used continuously up to six times with 98% conversion of pollutants without substantial loss in catalytic activity. It was observed that these types of hydrogel systems can be used for the conversion of pollutants from waste water into useful products.

scholarly journals Rapid four-component synthesis of dihydropyrano[2,3-c]pyrazoles using nano-eggshell/Ti(IV) as a highly compatible natural based catalyst

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi Bi Fatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Reaction Times ◽  
Diffraction Field ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Work Up

AbstractNano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are mild condition, short reaction times, easy work-up, high yields, reusability of the catalyst and the absence of toxic organic solvents.

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