Cavity formation in a tensile loaded alumina particulate composite
Horizontal stringers of fine oxide particles can be seen, parallel to the extrusion direction (horizontal). Under the tensile load, voids have nucleated at the interface between the matrix and the reinforcement particles, and some particle fracture has also occurred. Most voids form on planar faces normal to the tensile load (horizontal), and particularly where stringers of fine oxide particles also intersect the interface. These stringers provide interfacial flaws which may then be preferential
Fracture surface in a liquid crystalline polymer, oriented by a magnetic field
Above their melting point, liquid crystalline polymers exhibit a mesophase within which, although able to flow and are not arranged in a crystal, they exhibit long range orientational order. This molecular alignment can be exploited to make high strength and stiffness fibres such as Kevlar, or even mouldable thermotropics such as Vectra. Molecular alignment can also be controlled by an external applied field; a property exploited in liquid crystal displays. This polymer has been subjected to a m
Ni-Superalloy, exposed microstructure
Following exposure at temperature typical of that found in the modern gas turbine engine, there exist two white phases, one with intergranular distribution and the other smaller particles, apparently randomly distributed. The larger semi-continuous intergranular phase is likely to be either the M23C6 carbide or the deleterious TCP phase, σ. Previous work has concluded that this phase is indeed σ, which is detrimental to mechanical strength, in particular creep life by embrittlement of the grai
The grain structure of extruded aluminium
The extrusion process leads to the elongation of grains. This micrograph shows a longitudinal section with the extrusion direction lying horizontal. Some large subgrains (or groups of subgrains) are apparent, and some high angle boundary migration has occurred normal to the extrusion direction. Grains near the extrudate centre have a lower aspect ratio.
Fe, C 0.8 (wt%) steel, eutectoid transformation, spheroidised
This steel is of the eutectoid composition. Once the temperature is lowered below the eutectoid temperature, the austenite phase tends to undergo a eutectoid transformation (γ to α + Fe3C). The resultant microstructure, known as pearlite, comprises alternate lamellae of cementite and ferrite. Subsequent to casting, the alloy was normalised (annealed) just below the eutectoid temperature, in order to induce the carbides to take a spherical appearance, which results in the steel becoming softer
Slip by dislocation glide
Animation of slip by dislocation glide. Dislocation glide allows plastic deformation to occur at a much lower stress than would be required to move a whole plane of atoms past another. See also the bubble raft experiment (videos 17 and 18). From TLP: Introduction to dislocations, http://www.msm.cam.ac.uk/doitpoms/tlplib/dislocations/dislocation_glide.php
Anisotropic dielectric permittivity: tetragonal-cubic phase transition in barium titanate
A thin section of barium titanate is viewed between crossed-polars, Initially, the sample is below the transition temperature, and since the domains of the anisotropic tetragonal phase exhibit birefringence, it is brightly coloured when viewed between crossed-polars. When the sample reaches the transition temperature, the isotropic cubic phase forms, which appears black. From TLP: Introduction to Anisotropy, http://www.msm.cam.ac.uk/doitpoms/tlplib/anisotropy/dielectric.php
Anisotropic thermal conductivity in quartz: parallel to c-axis section
A section of quartz cut parallel to the c-axis being heated from a point at its centre. An ellipse shows that the thermal conductivity in this plane is direction-dependent. From TLP: Introduction to Anisotropy, http://www.msm.cam.ac.uk/doitpoms/tlplib/anisotropy/thermal.php
Maritime Transportation, Chemistry and Oil
These files outline a general introduction to a joint view of maritime transportation, chemistry and crude oil and petroleum products. They include study material and self evaluation tests, which could be covered in 35 hours. This material is suitable for 1st year undergraduate students enrolled in Nautical or Maritime Engineering Studies, and also for a general audience.
The Changing Workplace
The 20th century ushered in a change from handcrafting to machine tooling. Henry Ford introduced one of the first moving assembly lines as a way to turn out more cars more quickly, and the emerging auto industry popularized this mode. A photo of the Doble Steam Motors Corporation factory shows a line of workers and car chassis in production. This new technology, and the spread of industrialization, changed forever the way that work was completed. A wide variety of industries all across the count
International Classification of Function, Disability and Health
This package was originally designed for undergraduates in Medicine at the University of Nottingham. It will also be useful to students in nursing, allied health professions and pharmacy. Practitioners in these fields, who are new to the ICF, will also find it a useful introduction. It describes the International Classification of Functioning, Disability and Health (ICF), a classification system published by the World Health Organisation to describe health status. This system is widely used in r
Researching solutions to global water shortages
Director of the University of Nottingham’s Centre for Clean Water Technologies. Making sure the world’s population has enough drinking water is one of the biggest challenges we face today. A rapidly increasing global population, the fact that only a very small percentage of global water is available for consumption and an uneven global distribution of clean drinking water are the main problems in regard to the current global water crisis. Professor Hilal discusses these problems and some of
Learning Objectives for Introductory Statistics
This text document lists detailed learning objectives for introductory statistics courses. Learning objectives are brief, clear statements of what learners will be able to perform at the end of a course.
Delamination cracks in h-BN particles.
h-BN particles were subjected to compressive stress in the (0001) planes (within a silicon nitride particulate-reinforced silicon carbide composite). The occurrence of BN inclusions results from the introduction of colloidal BN into the hot isostatic pressing process. They are formed from B2O3 present as a thin surface film on the BN particles in the barrier layer. B2O3 will be molten during the pressing process and will diffuse rapidly into the powder compact and react with Si3N4 to form BN. Su
Population and Development
This module on population and development is part of the World Bank Group's educational site that addresses sustainable development in the world. An introduction, objectives, activities, and references are provided. Educators can use the activities to help students understand population growth rates.
Introducing Regional Integration
This course is designed as a general introduction to regional integration, and is particularly aimed at non-specialists. It reviews some of the main definitions of what constitutes a region, and identifies the basic concepts and approaches to integration. The course portrays both the diversity and the hierarchical nature of regionalism, and calls attention to the motivations that lead groups of states and regions to elect for one particular form of regional cooperation over another. The course
Antiretroviral treatment programmes in Nepal: Problems and barriers.
The main aim of this study is to identify barriers and obstacles to providing and expanding ARV programmes in Nepal. Materials and methods: A qualitative approach consisting of in-depth interviews with three groups of stakeholders: policy makers, ARV service providers and ARV recipients were carried out. The transcripts were analysed using a thematic approach. Results: The estimated number of people in need was high compared with people currently receiving ARV in Nepal. With regards to the prope
Medicine Games: Control of the Cell Cycle
Play a game and find out about a Nobel Prize awarded discovery or work! In this game you are to take on the job as a Cell Division Supervisor. Are you familiar with the different phases in the cell cycle? If not, maybe you should pay extra attention to the image of the cell cycle in the introduction.
This topic starts with a basic introduction to muscles and an image illustrating the possible locations of the different muscle tissues. The three types of muscle tissue are described in more detail. Along with the features of muscle tissue (e.g. contractibility), the functions of these tissues (e.g. support) are discussed.
Good Practice Guide in Question and Test Design
This booklet will provide an introduction to good practice in question and test design. It includes the art of using objective tests to assess some aspects of student learning. At the outset you should be aware that objective tests are just one method of assessment. They are useful for assessing knowledge, comprehension and application and in some circumstances can be used to assess higher order skills such as evaluation and synthesis. They cannot be used to assess creativity, integration of ide