2.1 Case study: Redcar & Cleveland Mind
Frontline managers are responsible for gathering service user views on their needs. Whose views should be taken into account? How do managers gather views? This unit helps you consider ways of getting feedback from service users, and shows the inclusive approach of a manager of a voluntary sector mental health service.
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Frontline managers are responsible for gathering service user views on their needs. Whose views should be taken into account? How do managers gather views? This unit helps you consider ways of getting feedback from service users, and shows the inclusive approach of a manager of a voluntary sector mental health service.
Author(s): The Open University

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Elon Spotlight: Paul Castro
Professional screenwriter Paul Castro joined the School of Communications faculty this year as a visiting professor in cinema. Video by Sean Glynn
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Artificial Streams
UM researchers Scott Knight and Rich Lizotte have started a new research project at the Ole Miss Field Station that involves building artificial streams to simulate Delta wetlands. The research is examining the oxygen content of the water and soil. Learn more about the project by watching the video. Video by Tobie Baker.
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Backdoor broadcasting company : Tim Thornton : Clinical Judgement and the Medical Humanities
This section of the Backdoor Broadcasting Company website makes recordings of academic lectures available to researchers and members of the public. Here, a lecture delivered by Tim Thornton of the University of Central Lancashire on 25 November 2009 at The Humanities and Arts Research Centre, Royal Holloway University of London is posted as a podcast. The lecture, "Clinical Judgement and the Medical Humanities" deals with areas of ethics and contemporary philosophy and linguistic studies relat
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What Drives Profits?

The economic and business community constantly attempts to forecast the effects of various economic changes and government policies on corporate profits. But both the cause and effect of increasing profits are other than what most people imagine. It will therefore be helpful to gain a concrete understanding of what profits do and do not represent.[1]


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20 Crime and illness: the thin blue line
20th Maudsley Debate Crime and illness: the thin blue line? This house believes that criminals need treatment not punishment Proposing the motion:Prof. John Gunn, Forensic Psychiatry, IOP and Prof. Christopher Cordess, Forensic Psychiatry, University of Sheffield. Opposing the motion: BRENDAN O'NEILL - Assistant Editor, SPIKED PHILIP BEAN - Director, Midlands Centre for Criminology and Criminal Justice
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2.4 Chain conformations

The repeat units or chains shown in the previous figures are all static representations of real chains and they are therefore of limited use. The key idea we need to explore real chains, and their influence on properties is that of the conformation of a chain. A single conformation is just a single shape that a chain can adopt, so that for example, when a polyethylene chain is shown as a linear zig-zag, this is one possible conformation. Static formulae do not show an important aspect
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2.3.6 Copolymers

So far, the discussion has been confined to polymers with only a single type of repeat unit, but in reality, a large and growing number of commercial polymers are actually composed of different types of unit attached together by chemical covalent bonds. They are known as copolymers, and can comprise just two different units (binary copolymers) or three (ternary), and so on. It is one of the common strategies used by molecular engineers to manipulate the properties of polymers to gain j
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2.3.5 Repeat unit placement

A final kind of isomerism in homopolymers is possible when monomer units are added to a growing chain in reverse rather than in their normal position. Because monomer molecules have a particular shape in space, they will normally approach a growing chain end to minimise any spatial interaction, and a regular chain structure results from head-to-tail joints. A defective joint can sometimes occur, however, when heads combine to form a head-to-head joint (Author(s): No creator set

2.3.4 Stereoisomerism

A final type of isomeric variation occurs as a result of the three-dimensional structure of some polymers. It is possible because a four-valent atom like carbon can exist in two different forms when the subsidiary groups or atoms attached to the carbon are all different. The carbon atom is then known as an asymmetric carbon atom. A very simple example of the phenomenon is the structure of a small molecule, lactic acid. As Figure 20 shows, it can exist in two forms which are mirr
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2.3.3 Geometrical isomerism

A second type of isomerism occurs with diene monomers, and is present in both NR and butadiene rubbers (BR). It occurs because the single double bond in the final polymer can exist in two ways: a cis form and a trans form. The repeat unit shown in Table 3 for NR does less than justice to the two-dimensional structure of this material (Author(s): No creator set

2.3.2 Chain branching

A germ of the idea is shown by the formulae for 2- and 3-methylpentane in Figure 16. A single methyl group (CH3—) can occur in two different positions along an essentially linear carbon-carbon chain. The methyl group is a very simple kind of branch along the chain, and it is easy to extend the idea to much larger molecules. Thus LDPE is a polymer based on a linear backbone chain with the repeat unit [CH<
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2.3.1 Structural isomerism

In the saturated hydrocarbons, whose structural formulae are shown in Figure 16, it is not possible to form distinct isomers with just three or less carbon atoms linked together. There is only one way in which one carbon and four hydrogen atoms can be linked together, the single compound being methane, CH4. A similar situation holds for ethane, C2H6 and propane, C3H8.
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2.3 Chain configuration

The structure of repeat units is fixed by the chemical bonds between adjacent atoms. The shape or shapes thus created is known as the configuration, and for chains will be the chain configuration. Like children's plastic building blocks, however, there can be many different configurations for a given set of atoms of a particular type. The different structures which have identical chemical formulae are known as isomers, and such isomers can have quite different properties. Isomer
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2.2 Chain repeat units

The repeat units of a range of polymers together with the monomer units from which they are derived are shown in Table 3. The simplest repeat unit is that for polyethylene, and consists of two carbon atoms linked to four hydrogen atoms. The difference between the monomer and the repeat unit is the loss of the double bond in the former to give the chain-linked repeating group. Thus the molecular masses of both monomer and unit are identical at 28. The molecular mass of the repeat unit is usual
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2.1 Understanding the polymer state

It was the pioneering scientific work of Hermann Staudinger in the early part of the twentieth century which led to an understanding of the polymer state at an atomic and molecular level. Until then, plastics and rubbers had been developed from naturally occurring substances or discovered during routine synthesis. His research laid the basis for all subsequent discoveries and their commercial development. In essence, he realised that polymers were large molecules built up by the repetition of
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1.3 Product design and manufacture

So what are the reasons for the continued growth in the use of polymers as shown in Figure 1? It cannot be raw material cost, since the source of synthetic polymers is crude oil or natural gas, prices of which have risen over the same period of time. The comparative prices of polymers are considerably greater than traditional materials like mild steel, so we must look elsewhere for their success.

It is really necessar
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1.2 Polymer types

Traditionally, the industry has produced two main types of synthetic polymer – plastics and rubbers (Figure 3). The distinction is that plastics are, by and large, rigid materials at service temperatures while rubbers are flexible, low modulus materials which exhibit long-range elasticity. Plastics are further subdivided into thermoplastics and thermosets, the latter type being materials where the long chains are linked t
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1 1The growth of poymers

Polymers, or materials composed of long molecular chains, are now well-accepted for a wide variety of applications, both structural and non-structural, and for mass-manufactured as well as one-off speciality products. The growth in their use has continued in the last two decades or more, despite the effects of several recessions in industrial activity (Figure 1). In the same period the demand for traditional materials like
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