Effect of Surface Roughness on Adhesion and Corrosion Properties for Metal Surface

This report highlights t.he research work done by the author for the final year project entitled "Effect of Surface Roughness on Adhesion and Corrosion Properties for Metal Surface". The aspects that are covered in this report include the introduction of the project, literature review, the methodology used in achieving the objective of the project as well as the project planning and milestone, results and discussion, conclusion and recommendation. The objective of this project is to attain the clear correlation between the effect of various surface roughness towards the adhesion and corrosion properties of the coating process applied on the metal surface. The methodology part contains project research process flow and project planning with Gantt chart as the attachment. The discussion part will explain on the discovery from research and the way forward of the project. The study recover that there is a need to improve the coating system for the manufacturing purpose in the future. The conclusion consists of the overall conclusions and recommendations regarding the project

MANGANESE TOXICITY AQUTIC SYSTEM : AN IMPACT OF EXCESS MANGANESE IN SOLUTION CULTURE ON PLANT GROWTH

Mn2+ sangat larut di dalam system aquatic dimana prinsip kultur larutan adalah sama dengan system akuatik. Dua set eksperimen mengenai pengaruh konsentrasi Mn2+  di dalam kultur larutan terhadap pertumbuhan tanaman telah dilakukan di rumah kaca University Putra Malaysia, Serdang, Selangor, Malaysia. Studi ini bertujuan untuk mengetahui konsentrasi toksik Mn2+  di dalam kultur larutan pada pertumbuhan tanaman. Sebagai tanaman indicator adalah “vegetable soybean” (Glycine max L.) Pada eksperimen pertama menunjukkan 60 µM Mn berkesan sangat toksik pada pertumbuhan tanaman, sementara pada eksperimen kedua menunjukkan bahwa 7.5 µM adalah optimum. Penurunan berat kering daun, akar dan batang tanaman soybean sangat nyata pada taraf 37.5 µM. Ianya disebabkan oleh pengurangan luas daun dan panjang akar dengan penambahan konsentrasi Mn2+ pada kultur larutan

Finite element analysis of rotating oscillatory magneto-convective radiative micropolar thermo-solutal flow

Micropolar fluids provide an alternative mechanism for simulating micro-scale and molecular fluid mechanics which require less computational effort. In the present paper, a numerical analysis is conducted for the primary and secondary flow characterizing dissipative micropolar convective heat and mass transfer from a rotating vertical plate with oscillatory plate velocity, adjacent to a permeable medium. Owing to high temperature, thermal radiation effects are also studied. The micropolar fluid is also chemically-reacting, both thermal and species (concentration) buoyancy effects and heat source/sink are included. The entire system rotates with uniform angular velocity about an axis normal to the plate. Rosseland’s diffusion approximation is used to describe the radiative heat flux in the energy equation. The partial differential equations governing the flow problem are rendered dimensionless with appropriate transformation variables. A Galerkin finite element method is employed to solve the emerging multi-physical components of fluid dynamics problem are examined for a variety of parameters including rotation parameter, radiation-conduction parameter, micropolar coupling parameter, Eckert number (dissipation), reaction parameter, magnetic body force parameter and Schmidt number. A comparison with previously published article is made to check the validity and accuracy of the present finite element solutions under some limiting case and excellent agreement is attained. The current simulations may be applicable to various chemical engineering systems, oscillating rheometry, and rotating MHD energy generator near-wall flows

Mo (VI)/ZrO2 coated on honeycomb monolith as solid acid green catalyst for the acetylation of substituted alcohols and amines under solvent free conditions

553-561Honeycomb (HC) monolith coated with solid acids such as Mo (VI)/ZrO2 (MZ) with different Mo loadings (2, 6 and 10%) have been prepared by wet impregnation method and characterized by NH3 –TPD, BET surface area, PXRD, ICP-OES, SEM, TEM and EDAX techniques. These catalysts have been used as for the synthesis of O and N-acetylation reactions by the condensation of various alcohols with acetic anhydride under solvent free conditions in shorter times (20 min) at moderate temperature (70°C). Especially, 6% Mo (VI)/ZrO2 catalysts are found to be highly acidic and also resulted in high yields of O and N acetylated products up to ~99%. This methodology offers several advantages such as excellent yields, easy procedure, mild and environmentally benign conditions. MZ catalysts are found to be economical, efficient and highly active, recyclable and reusable up to 6 reaction cycles without much loss of their activity

Mineralogical and charge properties of volcanic ash soils from west Sumatra, Indonesia

Four volcanic ash soi1 from two toposequences along Mt Marapi and Mt Talaniau, west Sumatra were studied in order to characterize their mineralogical and charge properties. In all the soils, the silt fraction is composed mainly of gibbsite, cristobalite and feldspars, while the clay fraction is composed mainly of cristohalite, feldspars and halloysite. Gibbsite is only present in the clay fraction of the soils from Mt Talamau, while opal-A is only found in the clay of the soil from Mt Marapi. Allophane contents, computed from Si and Al extracted by ammonium oxalate and pynophosphate, are lower in the surface horizons than in the subsoil This is related to higher amounts of organic matter in the topsoil Due to higher rainfall, the soils of Mt Talamau are more weathered than those of Mt Marapi. This is reflected by lower allophane and higher ferrihydrite contents in the soils of Mt Talamau. In all the soils, the surface horizons have lower pH,, value than die under lying B-horizons. The AEC is higher in the subsoil than in the topsoil, having values of 0.3 -1.1 cmol, /kg soil

Rotating unsteady multi-physico-chemical magneto-micropolar transport in porous media : Galerkin finite element study

In this paper, a mathematical model is developed for magnetohydrodynamic (MHD), incompressible, dissipative and chemically reacting micropolar fluid flow, heat and mass transfer through a porous medium from a vertical plate with Hall current, Soret and Dufour effects. The entire system rotates with uniform angular velocity about an axis normal to the plate. Rosseland’s diffusion approximation is used to describe the radiative heat flux in the energy equation. The governing partial differential equations for momentum, heat, angular momentum and species conservation are transformed into dimensionless form under the assumption of low Reynolds number with appropriate dimensionless quantities. The emerging boundary value problem is then solved numerically with a Galerkin finite element method employing the weighted residual approach. The evolution of translational velocity, micro-rotation (angular velocity), temperature and concentration are studied in detail. The influence of many multi-physical parameters in these variables is illustrated graphically. Finally, the friction factor, surface heat transfer and mass transfer rate dependency on the emerging thermo-physical parameters are also tabulated. The finite element code is benchmarked with the results reported in the literature to check the validity and accuracy under some limiting cases and an excellent agreement with published solutions is achieved. The study is relevant to rotating MHD energy generators utilizing non-Newtonian working fluids and also magnetic rheo-dynamic materials processing systems

The Development of Moisture Sensitivity Test for Compacted Asphalt

Moisture damage is one of the major issues in asphalt distress. It is due to the adhesive andcohesive failure of asphalt mixture and it will shorten pavement life. Moisture-sensitivemixtures need to be identified during the course of the mixture design process which fulfillsthe specified minimum standard. The laboratory testing procedures currently available forcompacted Hot Mix Asphalt (HMA) to test the moisture sensitivity were primarily developedto determine the degree of resistance to moisture damage by a particular combination ofasphalt and aggregate. These moisture sensitivity tests evaluate the effect of moisture damagein laboratory by measuring the relative change of a single parameter before and afterconditioning (i.e., Tensile Strength Ratio, Resilient Modulus Ratio). The tests were simple toconduct and widely accepted by various state and federal agencies, but their drawback includethe empirical nature of the procedures, the dependence of the results on the moistureconditioning methodology and in several cases, the poor correlation with field performance.Many new approaches were conducted to overcome the weaknesses of the existing method.These new approaches mostly designed to conduct the test as close as the field condition andconsider the material properties of asphalt to give the useful result for the asphaltperformance. For better asphalt mixture design, it needs to have the test procedure whichconsidered the effect of traffic loading. The moisture conditioning methodology should avoidusing the vacuum saturation method since this method contributes to the asphalt mixturestrength. The scale of performance measurement can be conducted either microscale ormacroscle. Besides that the test also must be repeatable, reproducible, feasible, practical, andeconomical enough that it can be included in routine asphalt mixture design practice

Computational fluid dynamics analysis of moisture ingress in aircraft structural composite materials

Moisture in composite materials has been proven to be an important issue leading to significant deterioration of commercial aircraft wing structures. Lingering problems associated with this issue which is initiated with defects during manufacturing and finishing include delamination, de-bonding, potential fracture, debris etc. Despite extensive investigation and refinement in structural design, the water ingress problem persists as no general mitigation technique has yet been developed. Developing sustainable solutions to the water ingress problem can be very time-consuming and costly. The increasing use of composites in the aviation industry, in, for example, honeycomb sandwich components highlights the significant need to address the moisture ingress problem and develop deeper insights which can assist in combatting this problem. Experimental testing, although the most dependable approach, can take months, if not years. Numerical simulations provide a powerful and alternative approach to experimental studies for obtaining an insight into the mechanisms and impact of moisture ingress in aircraft composites. The principal advantage is that they can be conducted considerably faster, are less costly than laboratory testing, and furthermore can also utilize the results of laboratory studies to aid in visualizing practical problems. Therefore, the present study applies a computational fluid dynamics (CFD) methodology, specifically ANSYS finite volume software and the three fluid-based solvers, Fluent, CFX and ANSYS fluid structure interaction (FSI), to simulate water ingress in composite aerospace structures. It is demonstrated that ANSYS Fluent is a satisfactory computational solver for fundamental studies, providing reasonably accurate results relatively quickly, especially while simulating two-dimensional components. Three-dimensional components are ideally simulated on CFX, although the accuracy achievable is reduced. The structural-fluid based solver, ANSYS FSI (fluid structure interaction), unfortunately does not fully implement the material studied leading to reduced accuracy. The simulations reveal interesting features associated with different inlet velocities, inlet fastener hole numbers, void number and dimensions. Pressure, velocity, streamline, total deformation and normal stress plots are presented with extensive interpretation. Furthermore, some possible mitigation pathways for water ingress effects including hydrophobic coatings are outlined. KEY WORDS: Aircraft composites, Computational Fluid Dynamics, ANSYS, moisture ingress, Fluent, CFX, (fluid structure interaction) FSI, velocity, pressure, total deformation; elevator, mesh density