Physicochemical properties and tribological performance of motorbike lubricant dispersed with surface-modified WS2 nanoparticles

2019 ◽  
Vol 233 (9) ◽  
pp. 1379-1388 ◽  
Author(s):  
V Srinivas ◽  
RN Thakur ◽  
AK Jain ◽  
M Saratchandra Babu
Keyword(s):  
Physicochemical Properties ◽  
Fuel Consumption ◽  
Viscosity Index ◽  
Tribological Performance ◽  
Engine Oil ◽  
Engine Wear ◽  
Endurance Tests ◽  
The Stability ◽  
Surface Modified ◽  
Engine Components

This paper investigates the effect of dispersion of surface-modified WS2 nanoparticles on the tribological performance and physicochemical properties of motorbike lubricant. Surface-assisted WS2 nanoparticles were dispersed in motorbike engine oil and an optimum amount of surfactant for best stability of the lubricant suspension was found by investigating the changes in the physicochemical properties of lubricant. The stability analysis using light scattering techniques confirmed the stability of nanoparticles dispersed in lubricant medium and surface-modified WS2 nanoparticles remained stable for 180 days. The physicochemical properties were evaluated as per ASTM standards over a period of two months to check the state of lubricant and observable changes in the properties during this period. The tribological performance of the lubricants was assessed by conducting endurance tests on a 100 cc motor bike. The performance was evaluated by checking the wear of the engine components and fuel consumption. It was found that there were no abnormal changes in the physicochemical properties of lubricant up to a certain surfactant to nanoparticle ratio indicating its utility in automotive engines. However, if the amount of surfactant was increased beyond optimum quantity abnormal changes are seen in the viscosity index, leading to the deterioration of key lubricant properties. Lubricant dispersed with WS2 nanoparticles gave good performance characterized by the reduction in both engine wear and fuel consumption. Worn surfaces of the oil rings after the endurance test were assessed for deposits and it was found that a layer of WS2 deposited on the oil ring surface that reduced friction and wear.

Effect of hBN/Al2O3 Nanoparticle Additives on the Tribological Performance of Engine Oil

2014 ◽  
Vol 66 (3) ◽  
Author(s):  
Muhammad Ilman Hakimi Chua Abdullah ◽  
Mohd Fadzli Abdollah ◽  
Hilmi Amiruddin ◽  
Noreffendy Tamaldin ◽  
Nur Rashid Mat Nuri
Keyword(s):  
Diesel Engine ◽  
Hexagonal Boron Nitride ◽  
Fuel Efficiency ◽  
Tribological Performance ◽  
Engine Oil ◽  
Wear Scar Diameter ◽  
Engine Wear ◽  
The Coefficient Of Friction ◽  
Al2o3 Nanoparticle ◽  
Nanoparticle Additives

Nanotechnology currently has an important role in reducing engine wear and improving fuel efficiency within engines using nanoparticle additives in engine oil. In this work, the effect of hexagonal boron nitride (hBN) and alumina (Al2O3) nanoparticle additives, on the tribological performance of SAE 15W40 diesel engine oil, was studied. A tribological test was conducted using a four-ball tribotester. The results show that the coefficient of friction (COF) and wear rate of the ball reduced significantly by dispersing hBN nanoparticle additives in SAE 15W40 diesel engine oil; compared to without or with Al2O3 nanoparticle additives. This is in accordance with the significant reduction of wear scar diameter and smoother worn surfaces observed on the balls.

Lubricant Degradation Studies Using a Single Cylinder Research Engine

2005 ◽  
Author(s):  
P. M. Lee ◽  
M. Priest ◽  
M. S. Stark ◽  
J. J. Wilkinson ◽  
J. R. Lindsay Smith ◽  
...  
Keyword(s):  
Fuel Consumption ◽  
Tribological Performance ◽  
Operating Conditions ◽  
Engine Oil ◽  
Oil Degradation ◽  
Lubricant Degradation ◽  
Reduce Fuel Consumption ◽  
Single Cylinder ◽  
Degradation Studies ◽  
Piston Assembly

With increasing pressure on engine oil manufacturers to extend oil drain intervals and reduce fuel consumption, whilst changing the composition of fully formulated oils to meet new CEC, ILSAC and OEM specifications, there is ever increasing need to understand the effect of oil degradation on the operating conditions and tribological performance of engines. This poster presents mechanical changes made to a single cylinder research engine to enable the study of lubricant degradation, its transport and how this links to piston assembly tribology. A summary of the research undertaken using these changes and a sample of results obtained to date are also presented.

Comparison of the Stability of Surface-Modified SWNTs and DWNTs Network Films

2010 ◽  
Vol 114 (10) ◽  
pp. 4394-4398 ◽  
Author(s):  
Seung Bo Yang ◽  
Byung-Seon Kong ◽  
Dae-Woo Kim ◽  
Hee-Tae Jung
Keyword(s):  
The Stability ◽  
Surface Modified

Experimental Study on the Tribological Characteristics of Nanometer WS2 Lubricating Oil Additive Based on Engine Oil

2011 ◽  
Vol 328-330 ◽  
pp. 203-208 ◽  
Author(s):  
Cheng Bin Chen ◽  
Da Heng Mao ◽  
Chen Shi ◽  
Yang Liu
Keyword(s):  
Raw Materials ◽  
Viscosity Index ◽  
Engine Oil ◽  
Lubricating Oil ◽  
Contrast Study ◽  
Base Oil ◽  
Grinding Conditions ◽  
Lubricating Oil Additive ◽  
Great Wall ◽  
Better Than

Nano-WS2(tungsten disulfide nanoparticles)lubricating oil additive, prepared by the nanometer WS2particulates and semi-synthetic engine base oil as raw materials, was added into Great Wall engine oil with different mass ratio. With a contrast study on these oil samples, the results show that it can improve the extreme pressure, antiwear and viscosity-temperature properties of the engine oil effectively by adding a certain amount of nano-WS2additive, and the optimal concentration is 2wt%. The oil film strength, sintering load and viscosity index of this lubricating oil is respectively 1.35 times, 1.58 times and 1.05 times as that of Great Wall engine oil. In addition, when tested under the grinding conditions of 392 N, 1450 r /min and 30 min, the diameter of worn spot reduces 0.018mm, and the average friction coefficients of friction pairs decrease 16.3%, both of which are lubricated by the oil containing nano-WS2additive. Meanwhile, the experiments testify that the tribological and viscosity-temperature properties of the nano-WS2additive are better than that of the Henkel MoS2additive.

scholarly journals Natural Gums to Improve the Physicochemical Stability of Cake Creams

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2261
Author(s):  
Oscar López-Balladares ◽  
Patricio J. Espinoza-Montero ◽  
Ramiro Acosta-Sandoval
Keyword(s):  
Physicochemical Properties ◽  
Elastic Deformation ◽  
Bubble Size ◽  
Physicochemical Changes ◽  
Physicochemical Stability ◽  
Confectionery Products ◽  
Initial Appearance ◽  
Thixotropic Behavior ◽  
The Aesthetic ◽  
The Stability

The physicochemical properties of pastry and confectionery products greatly influence the aesthetic design of a cake topping, since they can be susceptible to physicochemical changes in a very short time, so maintaining a good appearance and texture of the topping becomes a challenge. Generally, cake creams deteriorate over time. The evaluation of the physicochemical properties of natural gums (arabic gum, tara gum, carrageenan, and pectin) is proposed in this work as a way to improve the physicochemical stability of butter-based cake creams (coverage creams) to maintain the initial appearance of the cream and to lengthen the separation time of their phases. For this purpose, some parameters related to the physicochemical stability of the cream, such as viscosity, density, bubble size, syneresis, volume and rheological behavior were measured. The result of the ANOVA and Tukey’s tests displayed significant differences for the measured parameters, which shows that natural gums substantially improve the stability of butter cream. The best natural gum found was the tara gum (TG) which improved viscosity 5.6 times with respect to that of the cream without gums (η¯ without gums = 15.49 Pa·s, η¯ with TG = 87.09 Pa·s), while the bubble size remained small, 1.6 times smaller compared to that of the cream without gum (BS¯) without gums = 57 μm, (BS¯) with TG = 35 μm), and the volume loss decreased two times when compared to that of the cream without gums ((ΔV¯) without gums = 1.57 cm3, (ΔV¯) with TG = 0.80 cm3). The cream with TG showed better rheology compared to that of the cream without gums (the cream without gums exhibited a plastic and thixotropic behavior, with permanent elastic deformation, while cream with TG exhibited thixotropic behavior without permanent elastic deformation). Finally, it was found that the cream with TG acquired a higher thixotropic index (TI) compared to that of the cream without gums (TI max. without gums = 17.40 y 71.78 q.u., TI max. with TG = 74.67 and 1559.90 q.u., at 4 °C and 25 °C, respectively) which demonstrates the effective contribution of cream with TG in 66.67% of the measured parameters.

scholarly journals Physicochemical Properties and Stability of Microencapsulated Betacyanin Pigments from Red Dragon Fruit Peels and Flesh

2020 ◽  
pp. 141-148
Author(s):  
Rosalinda C Torres ◽  
Rowelain Mae G Yumang ◽  
Chelsea Kate F Jose ◽  
Danielle Camille P Canillo
Keyword(s):  
Moisture Content ◽  
Physicochemical Properties ◽  
Morphological Characterization ◽  
Stability Study ◽  
Natural Colorant ◽  
Hygroscopic Moisture ◽  
Dragon Fruit ◽  
The Stability ◽  
Spray Dried ◽  
Hylocereus Polyrhizus

Dragon fruit (Hylocereus polyrhizus) is known for its purple-coloured peels and pulp, which can be attributed to the presence of betalains. In this study, the potential of red dragon fruit as a source of natural colorant was investigated. Betacyanins were extracted from red dragon fruit peels and flesh in 1:3 ratio with water. Microencapsulation by spray-drying was done by adding 5% and 10% (w/v) maltodextrin (DE 11.8) to peels and flesh extracts, respectively. The spray-dried colorant powders all obtained <10% moisture content, 5.261-6.409 g/100g hygroscopic moisture content, and 5.317-7.349(mg/100L) betacyanin content. Morphological characterization revealed spherical, agglomerated particles with visible cracks on the surface. The stability study conducted showed that pigment retention was lowest at 70°C and highest at 4°C. Keywords: Hylocereus polyrhizus; Red dragon fruit; Betacyanin; Microencapsulation; Physicochemical properties

scholarly journals Silver Nanoparticles Surface-Modified with Carbosilane Dendrons as Carriers of Anticancer siRNA

2020 ◽  
Vol 21 (13) ◽  
pp. 4647 ◽  
Author(s):  
Elżbieta Pędziwiatr-Werbicka ◽  
Michał Gorzkiewicz ◽  
Katarzyna Horodecka ◽  
Viktar Abashkin ◽  
Barbara Klajnert-Maculewicz ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Silver Nanoparticles ◽  
Lymphocyte Proliferation ◽  
Intracellular Transport ◽  
Genetic Material ◽  
Hydrodynamic Diameter ◽  
Transmission Electron ◽  
The Stability ◽  
Surface Modified ◽  
Sites Of Action

Gene therapy is a promising approach in cancer treatment; however, current methods have a number of limitations mainly due to the difficulty in delivering therapeutic nucleic acids to their sites of action. The application of non-viral carriers based on nanomaterials aims at protecting genetic material from degradation and enabling its effective intracellular transport. We proposed the use of silver nanoparticles (AgNPs) surface-modified with carbosilane dendrons as carriers of anticancer siRNA (siBcl-xl). Using gel electrophoresis, zeta potential and hydrodynamic diameter measurements, as well as transmission electron microscopy, we characterized AgNP:siRNA complexes and demonstrated the stability of nucleic acid in complexes in the presence of RNase. Hemolytic properties of free silver nanoparticles and complexes, their effect on lymphocyte proliferation and cytotoxic activity on HeLa cells were also examined. Confocal microscopy proved the effective cellular uptake of complexes, indicating the possible use of this type of silver nanoparticles as carriers of genetic material in gene therapy.

scholarly journals Evaluating the potential of surface-modified silica nanoparticles using internal olefin sulfonate for enhanced oil recovery

2019 ◽  
Vol 17 (3) ◽  
pp. 722-733 ◽  
Author(s):  
Afaque Ahmed ◽  
Ismail Mohd Saaid ◽  
Abdelazim Abbas Ahmed ◽  
Rashidah M. Pilus ◽  
Mirza Khurram Baig
Keyword(s):  
Silica Nanoparticles ◽  
Rheological Properties ◽  
Oil Recovery ◽  
Displacement Efficiency ◽  
Shear Rates ◽  
Oil Water ◽  
Core Flood ◽  
The Stability ◽  
Modified Silica Nanoparticles ◽  
Surface Modified

AbstractRecently, nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature reservoirs. Nanomaterials generally appear to improve oil production through wettability alteration and reduction in interfacial tension between oil and water phases. Besides, they are environmentally friendly and cost-effective enhanced oil recovery techniques. Studying the rheological properties of nanoparticles is critical for field applications. The instability of nanoparticle dispersion due to aggregation is considered as an unfavorable phenomenon in nanofluid flooding while conducting an EOR process. In this study, wettability behavior and rheological properties of surface-treated silica nanoparticles using internal olefins sulfonates (IOS20–24 and IOS19–23), anionic surfactants were investigated. Surface modification effect on the stability of the colloidal solution in porous media and oil recovery was inspected. The rheology of pure and surface-treated silica nanoparticles was investigated using a HPHT rheometer. Morphology and particle size distributions of pure and coated silica nanoparticles were studied using a field emission scanning electron microscope. A series of core-flood runs was conducted to evaluate the oil recovery factor. The coated silica nanoparticles were found to alter rheological properties and exhibited a shear-thinning behavior as the stability of the coated silica nanoparticles could be improved considerably. At low shear rates, the viscosity slightly increases, and the opposite happens at higher shear rates. Furthermore, the surface-modified silica nanoparticles were found to alter the wettability of the aqueous phase into strongly water-wet by changing the contact angle from 80° to 3° measured against glass slides representing sandstone rocks. Oil–water IFT results showed that the surface treatment by surfactant lowered the oil–water IFT by 30%. Also, the viscosity of brine increased from 0.001 to 0.008 Pa s by introducing SiO2 nanoparticles to the aqueous phase for better displacement efficiency during chemical-assisted EOR. The core-flood experiments revealed that the ultimate oil recovery is increased by approximately 13% with a surfactant-coated silica nanofluid flood after the conventional waterflooding that proves the potential of smart nanofluids for enhancing oil recovery. The experimental results imply that the use of surfactant-coated nanoparticles in tertiary oil recovery could facilitate the displacement efficiency, alter the wettability toward more water-wet and avoid viscous fingering for stable flood front and additional oil recovery.

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