Mechanical Engineering Commons^™

Anodisation Of Copper In Thiourea-And Formamidine Disulphide-Containing Acid Solution.: Part I. Identification Of Products And Reaction Pathway

A.S. Md Abdul Haseeb

The anodic behaviour of copper in aqueous 0.5 M sulphuric acid containing different amounts of dissolved thiourea or formamidine disulphide was investigated at 298 K, combining data from electrochemical polarisation, chemical analysis, UV–vis spectroscopy, XPS and EDAX analysis, and structural information on copper–thiourea complexes. The main reactions depend on the applied potential and initial thiourea concentration. In the potential range −0.30≤E≤0.075 V (versus SCE), the electro-oxidation of thiourea to formamidine disulphide, the formation of Cu(I)–thiourea soluble complexes, and Cu(I)–thiourea complex polymer-like films, are the most relevant processes. The formation of this film depends on certain critical thiourea/copper ion molar concentration …

Mössbauer Investigation On Electrodeposited Fe-C And Fe-Ni-C Alloys

A.S. Md Abdul Haseeb

Hard Fe-C based alloys, Fe-0.96 mass% C and Fe-15.4 mass% C having a microhardness of 810 and 750 HV, respectively, are electrodeposited from sulfate-based baths at 50°C. The Mössbauer spectra consist of high intensity sextet due to ferromagnetic Fe. The linewidth of the sextet is larger for alloys than for the pure Fe, indicating an increased effective field at different Fe sites in the alloys. Absence of any low intensity sextet, which is attributable to the Fe atoms close to the C atoms at the octahedral c-axis position, suggests that the electrodeposited alloys are in an advanced state of aging. …

Thermal Decomposition Study Of Electrodeposited Fe-C And Fe-Ni-C Alloys By Differential Scanning Calorimetry

A.S. Md Abdul Haseeb

Fe-0.96mass%C and Fe-15.4mass%Ni-0.70mass%C alloys with hardness of 810 and 750 HV respectively have been electrodeposited at 50°C from sulphate based baths containing a small amount of citric acid and L-ascorbic acid. Differential scanning calorimetry of the electrodeposited samples has been carried out in the temperature range of 293-725 K in argon atmosphere. Electrodeposited pure Fe is also investigated for comparison purposes. The DSC curves of both alloys contain two exothermic peaks: at about 411 K and 646 K for the Fe-C alloy, and 388 K and 639 K for the Fe-Ni-C alloy. These peaks are irreversible and do not appear …

Tribological Behaviour Of Quenched And Tempered, And Austempered Ductile Iron At The Same Hardness Level

A.S. Md Abdul Haseeb

The tribological behaviour of ductile iron heat-treated by two different procedures viz. quenching and tempering, and austempering to an identical matrix hardness of 445 KHN is compared. Wear tests were carried out using a pin-on-disc type apparatus under dry sliding conditions at a linear speed of 1.18 m s -1. Applied load and sliding distance in the range of 7.5-30 N and 2x10 4-6x10 4 m, respectively, were used. It was observed that under all test conditions, austempered ductile iron exhibits a better wear resistance than quenched and tempered ductile iron, although both have an identical chemical composition and matrix …

Effect Of Mechanical Factors On Tribological Properties Of Palm Oil Methyl Ester Blended Lubricant

A.S. Md Abdul Haseeb

The effects of mechanical factors viz. applied load and temperature on the tribological performance of 5% palm oil methyl ester (POME) blended lubricant were studied using a steel-cast iron pair. Wear and frictional measurements were made using a stationary steel ball and a reciprocating cast iron plate in a modified universal wear and friction testing machine. The test conditions were contact pressure, 400 MPa; mean contact velocity, 0.34 m/s; reciprocating stroke, 80 mm; loads, 100-1100 N (fixed temperature); and temperature, 40-140°C (fixed load). Wear scar surfaces were investigated using scanning electron microscopy (SEM) to understand the wear mechanisms involved. Analysis …

A Comparative Wear Study On Heat-Treated Aluminium-Lithium Alloy And Pure Aluminium

A.S. Md Abdul Haseeb

Wear behaviour of solution-treated and aged aluminium-lithium alloy (2.5% Li, 2% Cu, 1% Mg and 0.15% Zr) was compared with that of pure aluminium. Wear tests were carried out in ambient air in a pin-on-disc type apparatus under dry sliding conditions using hardened steel disc as the counterbody. A normal load of 10 N and a linear speed of 0.98 m s-1 were used during the tests. Microscopic investigation, microhardness measurement on the subsurface of wear scars on pins, X-ray diffraction study and morphological examination of wear debris were done to elucidate wear mechanism. It has been found that the …

Mass Transfer With Chemical Reaction In The Process Of Ammonia Desorption From Aqueous Solutions Containing Carbon Dioxide, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Xrd, Xps And Sims Investigations On Electrodeposited Nickel-Phosphorous Alloy Coatings

A.S. Md Abdul Haseeb

Structural and chemical investigations on electrodeposited nickel-phosphorous alloy coatings by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) are described. Electrodeposition of nickel-phosphorous coatings has been carried out galvanostatically in a hypophosphite bath at two different current densities, namely 20 and 80 mA cm -2. XRD has shown a broad peak indicating an amorphous structure in both cases. XPS shows the presence of Ni 2P compound. XPS also reveals the amount of phosphorous in both coatings to be around 10.20 wt.%. SIMS has shown that the coating deposited at lower current density (20 mA cm …

Novel Rotary-Turbo-Inflow Tech - Gearturbine Project - Featured Development, Carlos Barrera

Carlos Barrera

GEARTURBINE PROJECT Atypical InFlow Thermodynamic Technology Proposal Submission Novel Fueled Motor Engine Type

*State of the art Innovative concept Top system Higher efficient percent. Have similar system of the Aeolipile Heron Steam device from Alexandria 10-70 AD. -New Form-Function Motor-Engine Device. Next Step, Epic Design Change, Broken-Seal Revelation. -Desirable Power-Plant Innovation.

YouTube; * Atypical New • GEARTURBINE / Retrodynamic = DextroRPM VS LevoInFlow + Ying Yang Thrust Way Type - Non Waste Looses

-This innovative concept consists of hull and core where are held all 8 bteps of the work-flow which make the concept functional. The core has several gears …

اطلاعیه مهم

Omid Deymi

No abstract provided.

نمرات امتحان

Omid Deymi

No abstract provided.

پاسخ سؤالات سری سوم و چهارم

Omid Deymi

No abstract provided.

نکات و مثالهای فصول 6 و 7

Omid Deymi

No abstract provided.