Silver-Chloride, a Model Material for Photoelastic Investigations into Plastic-Elastic Behaviour of Machine-Elements

Automatic Transmission (AT) system is efficient in the aspects of vehicle safety, comfort, reliability and driving performance. The objectives of this paper are to collect the oil samples from AT systems of engine bus according to manufacturer's recommendations and analyse collected oil samples using oil analysis technique. The sample transmission fluid which was taken from the AT gearbox has been experimentally analyzed. The oil samples were taken with an interval of 5,000km, 30,000km, 50,000km, 80,000km, 180,000km and 300,000km for AT bus operation. These samples then have been analyzed by comparing between new and used transmission fluid using Fourier Transform Infrared (FTIR) spectroscopy. Oil analysis by FTIR is a form of Predictive Maintenance (PdM) to avoid major failure in machine elements. Most machine elements are not easily accessible in the transmission system. Having a reliable technique would avoid the needs to open the components unnecessarily, hence, help to prevent catastrophic failure which are very costly, and ease of regular monitoring. In order to identify the major failures of automatic gearbox, forecasts can be made regarding the lube transmission fluid analysis test. By using this test, the minor problems can be determined before they become major failures. At the end of this research, the wear particles profile for interval mileage of AT system was obtained. Keywords: Wear, Automatic Transmission (AT), Transmission fluid, Fourier Transform Infrared (FTIR), Oil analysis.

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SEISMIC CAPACITY OF MEDIUM SIZE CONTINUOUS BRIDGES WITH LEAD-RUBBER BEARINGS

NED University Journal of Research ◽

10.35453/nedjr-stmech-2019-0091 ◽

2019 ◽

Vol 3 (Special Issue on First SACEE'19) ◽

pp. 199-206

Author(s):

Bertha Olmos ◽

José Jara ◽

José Luis Fabián

Keyword(s):

Seismic Performance ◽

Seismic Vulnerability ◽

Base Isolation ◽

Elastic Behaviour ◽

Medium Size ◽

Nonlinear Behaviour ◽

Seismic Capacity ◽

Damage Scenarios ◽

Isolation Systems ◽

Rubber Bearings

This paper investigates the effects of the nonlinear behaviour of isolation pads on the seismic capacity of bridges to identify the parameters of base isolation systems that can be used to improve seismic performance of bridges. A parametric study was conducted by designing a set of bridges for three different soil types and varying the number of spans, span lengths, and pier heights. The seismic responses (acceleration, displacement and pier seismic forces) were evaluated for two structural models. The first model corresponded to the bridges supported on elastomeric bearings with linear elastic behaviour and the second model simulated a base isolated bridge that accounts for the nonlinear behaviour of the system. The seismic demand was represented with a group of twelve real accelerograms recorded on the subduction zone on the Pacific Coast of Mexico. The nonlinear responses under different damage scenarios for the bridges included in the presented study were estimated. These results allow determining the seismic capacity of the bridges with and without base isolation. Results show clearly the importance of considering the nonlinear behaviour on the seismic performance of bridges and the influence of base isolation on the seismic vulnerability of medium size bridges.

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Nonlinear Elastic Behaviour of Bushveld Rock

Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium ◽

10.36487/acg_repo/808_90 ◽

2008 ◽

Author(s):

Jan Kuijpers ◽

Bryan Watson ◽

G Henry

Keyword(s):

Elastic Behaviour ◽

Nonlinear Elastic

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Increasing in wear resistance of excavating machine elements

10.36652/1813-1336-2020-16-7-306-308 ◽

2020 ◽

pp. 306-308

Author(s):

V.S. Bochkov

Keyword(s):

Wear Resistance ◽

Wear Rate ◽

Abrasive Wear ◽

Thermomechanical Treatment ◽

Cold Work ◽

Hadfield Steel ◽

Outer Side ◽

Viii And Ix ◽

Machine Elements ◽

The Impact

The relevance of the search for solutions to increase the wear resistance of bucket teeth of excavating machine type front shovel is analyzed. The reasons for the wear of the teeth are considered. It is determined that when excavating machines work for rocks of VIII and IX categories, impact-abrasive wear of the inner side of the teeth and abrasive external wear occurs. It is proved that the cold-work hardening of Hadfield steel (the teeth material), which occurs during the excavating machine teeth work in the rocks of VIII and IX categories, reduces the impact-abrasive wear rate on the inner side of the teeth and does not affect the abrasive wear of the outer. The methods for thermomechanical treatment of the outer side of the excavating machine tooth is proposed. It can increase the wear resistance of Hadfield steel (110G13L) up to 1.7 times and lead to the self-sharpening effect of the tooth due to equalization of the wear rate of the outer and inner parts of the tooth. The efficiency factor of thermomechanical treatment to reduce the of abrasive wear rate of Hadfield steel is experimentally proved.

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Silver Chloride/Triphenylphosphine-Promoted Carboxylation of Arylboronic Esters with Carbon Dioxide at Atmospheric Pressure

Current Organic Synthesis ◽

10.2174/1570179414666170912170008 ◽

2018 ◽

Vol 14 (8) ◽

Author(s):

Zhi-Hua Zhou ◽

Chun-Xiang Guo ◽

Jia-Ning Xie ◽

Kai-Xuan Liu ◽

Liang-Nian He

Keyword(s):

Carbon Dioxide ◽

Atmospheric Pressure ◽

Silver Chloride

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Facile and Fast Detection of Genistein in Derris scandens by Square Wave Voltammetry using a Cobalt(II) Phthalocyanine-Modified Screen-Printed Electrochemical Sensor

Current Analytical Chemistry ◽

10.2174/1573411014666180521091053 ◽

2020 ◽

Vol 16 (3) ◽

pp. 341-348

Author(s):

Surinya Traipop ◽

Suchada Chuanuwatanakul ◽

Orawon Chailapakul ◽

Eakkasit Punrat

Keyword(s):

Electrochemical Sensor ◽

Square Wave Voltammetry ◽

Silver Chloride ◽

Reference Electrode ◽

High Sensitivity ◽

Plastic Substrate ◽

Fast Analysis ◽

Square Wave ◽

Wave Voltammetry ◽

Screen Printed

Background: Recently, Derris scandens, a Thai herbal medicine with anti-inflammatory activity, is widely used as beverage and supplementary food. When the traditional medicine is a choice for health therapy, the simple and reliable equipment is required to control the suitable consuming amount of the active component. Objective: To develop the electrochemical sensor for genistein determination in Derris scandens with high sensitivity and rapid operation. Methods: An in-house screen-printed electrochemical sensor consisting of a three-electrode system was developed for genistein determination. A silver/silver chloride (Ag/AgCl) reference electrode, a carbon counter electrode and a carbon working electrode were prepared on a 0.3-mm-thick plastic substrate by the screen-printing technique using conductive ink. The dimensions of each sensor were 2.5×1.0 cm. Only 50 µL of sample solution was required on this device for the determination of genistein concentration by rapid response square wave voltammetry. Results: The oxidation peak of genistein appeared with good response in acidic media at a peak potential of 0.6 V. Moreover, the signal was enhanced by modifying the conductive carbon ink with cobalt( II) phthalocyanine. Under the optimized conditions, the linear range was found to be 2.5-150 µM and the detection limit was 1.5 µM. Moreover, the small volume extraction was successfully developed without any further pre-concentration. This proposed method was applied to determine genistein in Derris scandens with satisfying results. Conclusion: The proposed method is promising as an alternative method for genistein determination with facile and fast analysis.

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Application of shotcrete constitutive model to the time dependent behavior of TBM tunnel lining

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.11293 ◽

2018 ◽

Vol 7 (3) ◽

pp. 1826

Author(s):

Heyam H. Shaalan ◽

Mohd Ashraf Mohamad Ismail ◽

Romziah Azit

Keyword(s):

Constitutive Model ◽

Steel Fibre ◽

Tunnel Lining ◽

Time Dependent ◽

Elastic Behaviour ◽

Elastic Analysis ◽

Time Dependent Behaviour ◽

Shotcrete Lining ◽

Creep And Shrinkage ◽

Dependent Behaviour

Shotcrete is ordinary concrete applied to the surface under high pressure. It demonstrates a highly time-dependent behaviour after few hours of application. Traditional approaches assume a simple linear elastic behaviour using a hypothetical young modulus to investigate the time-dependency and creep effects. In this paper, a new constitutive model of shotcrete is applied to evaluate the time-dependent behaviour of a TBM tunnel lining and investigate the parameters that can influence this behaviour. The Shotcrete model is based on the framework of Elasto-plasticity and designed to model shotcrete linings more realistically. The basic data of Pahang-Selangor Raw Water Transfer Project is used for the analysis study. An attempt is made to investigate the influence of some input parameters of the shotcrete model on the time-dependent behaviour of the shotcrete lining. These parameters include the time-dependent stiffness/strength parameters, creep and shrinkage parameters and steel fibre parameters. The variation in shotcrete strength classes causes a noticeable influence on the development of shotcrete compressive strength with time, particularly during the first days of application. The creep and shrinkage strain cause a considerable reduction in the development of the shotcrete stress with time. The impact of steel fibre content is determined, and the result indicated that the development of plain shotcrete stresses with time is lower than that of the reinforced shotcrete. In addition, a comparison study is performed to analyse the tunnel lining behaviour using both shotcrete model and an elastic analysis. Significant differences in shotcrete lining stresses are achieved when using the elastic analysis while the shotcrete model results in a reasonable result that can be used for the design requirements.

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