The Effect of the Short-Range Correlations on the Generalized Momentum Distribution in Finite Nuclei

The effect of dynamical short-range correlations on the generalized momentum distribution $n(\vec{p},\vec{Q})$ in the case of $Z=N$, $\ell$-closed shell nuclei is investigated by introducing Jastrow-type correlations in the harmonic-oscillator model. First, a low order approximation is considered and applied to the nucleus $^4$He. Compact analytical expressions are derived and numerical results are presented and the effect of center-of-mass corrections is estimated. Next, an approximation is proposed for $n(\vec{p}, \vec{Q})$ of heavier nuclei, that uses the above correlated $n(\vec{p},\vec{Q})$ of $^4$He. Results are presented for the nucleus $^{16}$O. It is found that the effect of short-range correlations is significant for rather large values of the momenta $p$ and/or $Q$ and should be included, along with center of mass corrections for light nuclei, in a reliable evaluation of $n(\vec{p},\vec{Q})$ in the whole domain of $p$ and $Q$.Comment: 29 pages, 8 figures. Further results, figures and discussion for the CM corrections are added. Accepted by Journal of Physics

Impact of curvature on the optimal configuration of flexible luminescent solar concentrators

Flexible luminescent solar concentrators (LSCs) could deliver integrated photovoltaics in all aspects of our lives, from architecture to wearable electronics. We present and experimentally verify a model for the optimization of the external optical efficiency of LSCs under varying degrees of curvature. We demonstrate differences between the optimization of flat and bent LSCs, showing that optimal fluorophore concentrations can differ by a factor of two

Losses in luminescent solar concentrators unveiled

A novel experimental method is presented to determine the optical efficiency and the loss channels of a luminescent solar concentrator (LSC). Despite strong promise, LSCs have not yet reached their full potential due to various mechanisms affecting the device's optical efficiency. Among those loss channels, escape cone and non-unity quantum yield losses are generally the most dominant. To further advance the field of LSCs, it is vital to understand the impact of each independently. So far, researchers have only characterized the total loss in LSCs. Here, an experimental method is proposed to separate the contribution from each individual loss channel. The experimental apparatus is the same as used for quantum yield measurements of fluorophores in solid samples. Therefore, the setup is commonly available to research groups already involved in LSC research. The accuracy of this method is demonstrated by comparing the experimental results with Monte-Carlo ray tracing. Our experimental method can have a strong impact on LSC research as it offers a means to unveil the loss channels of LSCs in addition to the optical efficiency

To what extent are we confident that tapentadol induces less constipation and other side effects than the other opioids in chronic pain patients? : A confidence evaluation in network meta-analysis

Open Access offered under Sage Agreement-waiting for decisionPeer reviewedPostprin

A Combined Experimental and Theoretical Study into the Performance of Multilayer Vanadium Dioxide Nanocomposites for Energy Saving Applications

In the built environment there is a increasing issue of heat management, with buildings expending significant energy resources to maintain comfortable living temperatures. In many parts of the world, this entails the use of both heating and cooling during daylight hours depending on ambient temperatures. Due to the variation in the desired temperature control classical solutions can become counter productive in their aim of maintaining comfortable temperatures, therefore it is important to employ adaptive solutions that vary their functionality based on circumstance. In recent years vanadium dioxide (VO2) has generated a broad range of interest due to its heat-mediated structural phase transition from a semiconductor to a metal, which occurs at a critical temperature that may be tuned via doping. The phase transition of VO2 significantly modulates its optical properties, with the high temperature metallic state absorbing and reflecting considerably more infrared radiation than the lower temperature monoclinic state due to the presence of free electrons; a window coated with a VO2 film may passively vary its transmission of infrared radiation based on the ambient temperature, in doing so reducing the temperature management energy-load. Here, we present a theoretically optimised design for a thermochromic smart window film based on a multilayer stack of silica, titania and vanadium dioxide (VO2) on a glass substrate and use the simulations to guide the fabrication process. The design makes use of coherent interference within the multi-layered structure to suppress reflection of visible light and improve the reflective component of solar modulation. In doing so, we are able simultaneously improve the visible transmission and solar modulation of the film above what would be possible with a single layer film. Additionally, the use of thin film VO2 also acts to reduce the detrimental transition hysteresis typically seen in small domain sized nanoparticulate VO2 films. The multilayer structure is fabricated via spin coating of sol-gel based precursors and subsequent annealing. After which the structure is optically characterised and results are compared with simulation along with standard single layer VO2 films and other nanoparticulate based VO2 films