Evaluation of near-infrared chemical imaging for the prediction of surface water quality parameters

Near-infrared (NIR) chemical imaging is an emerging technique with the potential for the detection of contaminants in the environmental field. In this study the potential of NIR chemical imaging (NIR-CI) to predict concentrations of nutrients (total nitrogen, total phosphorus) and indicator microorganisms (Escherichia coli) in surface water was investigated. Chemical images of multiple samples were obtained simultaneously using a pushbroom imaging system operating in the 950–1650 nm wavelength range with spectral resolution of 7 nm. Using partial least squares regression models, the relationship between these pollutants and NIR spectral data extracted from the chemical images in samples of aqueous surface water and filtered residue from surface water was assessed. When calibration models were tested on an independent data set, it was found that models developed on filtered residue spectra outperformed those developed on aqueous samples. For samples of filtered residue, the performance of the calibrations achieved for total nitrogen was reasonable (R² > 0.75); however, performance for total phosphorus and E. coli was poor (R² < 0.5). Lower concentrations of these parameters were detected in the surface water samples included in the study (<1 mg L^?1 and <20 colony-forming units per 100 mL, respectively), a likely reason for the poor performance. The results indicate that NIR-CI has the potential for screening samples in which the contaminant concentration exceeds 1 mg L^?1.     

Stakeholder Preference Mapping—seeking a way forward for the processing of spent nuclear fuel

Continuing concern in many countries about the processing of spent nuclear fuel has sparked new interest in how best to make evidence-based decisions about divisive issues. Stakeholder Preference Mapping (SPM), described here, is a way of applying multi-attribute decision analysis to structured dialogue and engagement with stakeholders. It uses the recorded views of stakeholders, supplemented where necessary by direct stakeholder contact, to understand and evidence stakeholder perspectives and to anticipate arguments for and against particular outcomes. It is illustrated in this paper through an exercise to examine competing options for the processing of spent nuclear fuel. The potential merits of SPM in terms of informing, focusing and accelerating stakeholder interactions and its relationship to other similar approaches are described and discussed.     

A reinforcement learning approach for the scheduling of live migration from under utilised hosts

Live virtual machine migration can have a major impact on how a cloud system performs, as it consumes significant amount of network resources, such as bandwidth. A virtual machine migration occurs when a host becomes over-utilised or under-utilised. In this paper, we propose a network aware live migration strategy that monitors the current demand level of bandwidth when network congestion occurs and performs appropriate actions based on what it is experiencing. The Artificial Intelligence technique that is based on Reinforcement Learning acts as a decision support system, enabling an agent to learn an optimal time to schedule a virtual machine migration depending on the current bandwidth usage in a data centre. We show from our results that an autonomous agent can learn to utilise available network resources such as bandwidth when network saturation occurs at peak times.     

Testing the accuracy of smartphones and sound level meter applications for measuring environmental noise

This paper reports on experimental tests undertaken to assess the capability of noise monitoring applications to be utilized as an alternative low cost solution to traditional noise monitoring using a sound level meter. The methodology consisted of testing 100 smartphones in a reverberation room. Broadband white noise was utilized to test the ability of smartphones to measure noise at background, 50, 70 and 90 dB(A) and these measurements were compared with true noise levels acquired via a calibrated sound level meter. Tests were conducted on phones using the Android and iOS platforms. For each smartphone, tests were completed separately for leading noise monitoring apps culminating in 1472 tests. The results suggest that apps written for the iOS platform are superior to those running on the Android platform. They show that one of the apps tested – SLA Lite – is within ±1 dB of true noise levels across four different reference conditions. The results also show that there is a significant relationship between phone age and its ability to measure noise accurately. The research has implications for the future use of smartphones as low cost monitoring and assessment devices for environmental noise.     

A novel carbon-carbon bond formation by the Lewis acid catalyzed reaction of β-styrylsilane with acetal

Treatment of (E)- and (Z)-β-styryltrimethylsilanes with benzaldehyde diethyl acetal in the presence of Lewis acid affords selectively 1,3,5-tri-phenyl-(E,E)- and (E,Z)-1,4-pentadienes, respectively.     

Photoelectron spectra of carbonyls: Acetaldehyde,acetamide, biacetyl,pyruvic acid,methyl pyruvate and pyruvamide

Photoelectron spectra of a number of carbonyl compounds are reported and assigned on the basis of a correlative scheme which makes heavy use of CNDO/s computations. The assignments of n and π_○ type for monocarbonyls, and n₊, n_?, π_⊕ and π_? type for α-dicarbonyls are quite secure in an experimental sense. All other assignments given are tentative.     

Host/guest deuteration effects on mixed crystals

The phosphorescence characteristics of twelve guest/host mixed crystal systems were investigated. A large thermally-activated intermolecular effect of host deuteration on the phosphorescence of the guest was noted. All observed effects can be rationalized using a kinetic model which implies thermal activation of triplet guest to triplet host, entrapment of energy at defects in the host exciton band, and the effects of deuteration on the thermal band gaps.     

The electronic states of nitroanilines

A correlation of spectroscopic data with all-valence-electron, $\text{CNDO}\text{s-CI}$ results has been performed for a number of mono- and disubstituted benzenes containing nitro and/or amino groups. The lowest energy transitions of p-nitroaniline are predicted to be 1¹B₁ ← 1¹A₁, 2¹A₁ ← 1¹A₁, and 2¹B₁ ← 1¹A₁, in the order of increasing energy. These three transitions are assigned to (i.e., are encompassed within) the lowest energy absorption band envelope of p-nitroaniline. The lowest energy predicted transition of o- and m-nitroanilines is 2A′ ← 1A′ and is supposed to correspond to the totality of the lowest energy absorption feature in both of these systems. The orbital excitation nature of these transitions is discussed.