Diatomic infrared gasdynamic laser permits selection of wavelengths

Laser utilizes infrared-active diatomic gas which emits laser energy from numerous upper vibrational levels. Wavelengths depend on particular vibration-rotation transitions and have been obtained throughout the band between 4.78 and 5.4 microns, for example, when using carbon monoxide

The First Conferences on the Theory of Economic Growth.

This paper presents the different conferences held around the subject of the theory of economic growth.ECONOMIC GROWTH ; ECONOMIC DEVELOPMENT ; ECONOMIC THEORY

The solar flare iron line to continuum ratio and the coronal abundances of iron and helium

Narrow band Ross filter measurements of the Fe 25 line flux around 0.185 nm and simultaneous broadband measurements during a solar flare were used to determine the relationship between the solar coronal abundances of iron and helium. The Fe 25 ion population was also determined as a function of time. The proportional counter and the Ross filter on OSO-7 were utilized. The data were analyzed under the separate assumptions that (1) the electron density was high enough that a single temperature could characterize the continuum spectrum and the ionization equilibrium, and that (2) the electron density was low so that the ion populations trailed the electron temperature in time. It was found that the density was at least 5x10 to the 9th power, and that the high density assumption was valid. It was also found that the iron abundance is 0.000011 for a helium abundance of 0.2, relative to hydrogen

A method of atmospheric density measurements during space shuttle entry using ultraviolet-laser Rayleigh scattering

An analytical study and its experimental verification are described which show the performance capabilities and the hardware requirements of a method for measuring atmospheric density along the Space Shuttle flightpath during entry. Using onboard instrumentation, the technique relies on Rayleigh scattering of light from a pulsed ArF excimer laser operating at a wavelength of 193 nm. The method is shown to be capable of providing density measurements with an uncertainty of less than 1 percent and with a spatial resolution along the flightpath of 1 km, over an altitude range from 50 to 90 km. Experimental verification of the signal linearity and the expected signal-to-noise ratios is demonstrated in a simulation facility at conditions that duplicate the signal levels of the flight environment

The class politics of prejudice: Brexit and the land of no-hope and glory

The debates relating to social class and whether it is still a useful concept in describing a lived reality of the British population has never been far away from media, political and academic dispute. Thatcher's Britain throughout the 1980s attempted to dilute class meaning with what was called 'a home owning democracy' and thus end class collective politics through easily available credit for the working class while simultaneously attacking trade union organization, recruitment and political action. During the late 1990s and into the noughties a 'New Labour' administration attempted to exacerbate the end of class politics through an agenda of a 'cultural distinction' to class identity. Class struggle, class politics and class identity is embedded deep within the cultural norms practices, and history of British democracy. Consequently it is difficult if not impossible to prise class inequality in the UK away from and out of national, local and personal politics (Savage et al. 2015: 393-8). This paper focuses upon the sense that class politics, and cultural class distinction, within the UK had the biggest influence in determining a working-class 'Leave Vote' in the 2016 referendum within the UK. This paper explores accounts and narratives from working-class 'leave' voters though an ethnographic study of the political and social viewpoints of working-class communities of East London, and of ex-mining towns of Nottinghamshire. Framing into fuller context the anger and apathy of being 'left out', arguing that being 'left out' has been part of working-class political narratives for over 30 years. Going beyond frustration and apathy, a significant part of the narrative of working people was of 'not existing', suggesting certain important linkages with ongoing debates about new ways of conceptualizing class differences and class structures. [Abstract copyright: © London School of Economics and Political Science 2017.

Recovery experiences of forensic mental health service users

Background: Current models of recovery are based on forensic mental health service users’ experiences. However, there is a lack of research into the experiences of those from ethnic backgrounds, despite being over-represented within forensic mental health settings. Aim: This research aimed to develop a framework for understanding the recovery experiences of forensic mental health service users of ethnic background. Methods: Upon gaining ethical approval, semi-structured interviews were held with 10 participants. The data were analysed using a critical realist approach to Grounded Theory. Findings: Five core categories were identified; the self, the network, the institution, recovery as a process, and the individual context. Similarities were drawn to existing models in which the self, network and institution interact to influence recovery. Differences were found regarding stigma. Individual context influenced the process, with cultural considerations regarding food, alternative treatments and spiritual beliefs playing an important role, as well as individuals’ experiences of adversity. Implications: It is concluded that the developed framework provides an initial understanding of the recovery experiences of this subgroup that can be used to develop services to meet the unique needs of this subgroup. Future research expanding on these findings is discussed

Two-photon excitation of nitric oxide fluorescence as a temperature indicator in unsteady gas-dynamic processes

A laser induced fluorescence technique, suitable for measuring fluctuating temperatures in cold turbulent flows containing very low concentrations of nitric oxide is described. Temperatures below 300 K may be resolved with signal to noise ratios greater than 50 to 1 using high peak power, tunable dye lasers. The method relies on the two photon excitation of selected ro-vibronic transitions. The analysis includes the effects of fluorescence quenching and shows the technique to be effective at all densities below ambient. Signal to noise ratio estimates are based on a preliminary measurement of the two photon absorptivity for a selected rotational transition in the NO gamma (0,0) band

The two-photon absorptivity of rotational transitions in the A2 Sigma hyperon + (v prime = O) - X-2 pion (v prime prime = O) gamma band of nitric oxide

A predominantly single-mode pulsed dye laser system giving a well characterized spatial and temporal output suitable for absolute two-photon absorptivity measurements was used to study the NO gamma(0,0) S11 + R21 (J double prime = 7-1/2) transition. Using a calibrated induced-fluorescence technique, an absorptivity parameter of 2.8 + or - 1.4 x 10 to the minus 51st power cm to the 6th power was obtained. Relative strengths of other rotational transitions in the gamma(0,0) band were also measured and shown to compare well with predicted values in all cases except the O12 (J double prime = 10-1/2) transition