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Working girls: abuse or choice in street-level sex work? A study of homeless women in Nottingham
This paper aims to explore how abused homeless women understand their choice to sex work. In particular, there is a discussion of the motivations given by women as to why they sex worked, and it is suggested that abused homeless women can experience coercion from abusive partners in deciding to sex work. There is a challenge to the notion of 'victim' within the government's 'Prostitution Strategy' (Home Office, 2006) in specifying responses to the complex needs of sex working women. Recommendations are also made for practice in the context of the 'Strategy' when working with abused and coerced homeless women who choose to sex work. Twenty-six homeless women were interviewed - nine of whom had sex worked - and a structured, qualitative questionnaire was used in a case study design from which information was gathered about the relationship between a woman's experience of abuse and her decision to sex work
Infrared diode laser spectroscopy of the fundamental band of NF(a1Δ)
Thirty-one lines of the fundamental vibration–rotation band of the NF free radical in its a 1 state have been detected in absorption near 8.6 µm using a tunable infrared diode laser. Linewidths were Doppler limited and several transitions were accompanied by resolved hyperfine structure due to fluorine and nitrogen nuclear moments. Wave number calibration using accurately determined N2O lines yielded v0 = 1165.952±0.001 cm^−1 for the band center. Rotational and centrifugal distortion constants for both v = 0 and 1 states have also been determined
Mechanisms for the Oxonolysis of Ethene and Propene: Reliability of Quantum Chemical Predictions
Reactions of ozone with ethene and propene leading to primary ozonide (concerted and stepwise ozonolysis) or epoxide and singlet molecular oxygen (partial ozonolysis) are studied theoretically. The mechanism of concerted ozonolysis proceeds via a single transition structure which is a partial diradical. The transition structures and intermediates in the stepwise ozonolysis and partial ozonolysis mechanisms are singlet diradicals. Spin-restricted and unrestricted density functional methods are employed to calculate the structures of the closed-shell and diradical species. Although the partial diradicals exhibit moderate to pronounced instability in their RDFT and RHF solutions, RDFT is required to locate the transition structure for concerted ozonolysis. Spin projected fourth-order Møller–Plesset theory (PMP4) was used to correct the DFT energies. The calculated pre-exponential factors and activation energies for the concerted ozonolysis of ethene and propene are in good agreement with experimental values. However, the PMP4//DFT procedure incorrectly predicts the stepwise mechanism as the favored channel. UCCSD(T) predicts the concerted mechanism as the favored channel but significantly overestimates the activation energies. RCCSD(T) is found to be more accurate than UCCSD(T) for the calculation of the concerted mechanism but is not applicable to the diradical intermediates. The major difficulty in accurate prediction of the rate constant data for these reactions is the wide range of spin contamination for the reference UHF wave functions and UDFT solutions across the potential energy surface. The possibility of the partial ozonolysis mechanism being the source of epoxide observed in some experiments is discussed
Fisher Information and Kinetic-energy Functionals: A Dequantization Approach
We strengthen the connection between Information Theory and
quantum-mechanical systems using a recently developed dequantization procedure
whereby quantum fluctuations latent in the quantum momentum are suppressed. The
dequantization procedure results in a decomposition of the quantum kinetic
energy as the sum of a classical term and a purely quantum term. The purely
quantum term, which results from the quantum fluctuations, is essentially
identical to the Fisher information. The classical term is complementary to the
Fisher information and, in this sense, it plays a role analogous to that of the
Shannon entropy. We demonstrate the kinetic energy decomposition for both
stationary and nonstationary states and employ it to shed light on the nature
of kinetic-energy functionals.Comment: 13 pages, 3 figures. To appear in J. Comput. Appl. Mat
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