Vector control against infectious diseases: Towards the sustainable development of insect repellents in New Caledonia

More than 80% of the world’s population is threatened by vector-borne diseases with populations in tropical regions most at risk. The World Health Organization (WHO) thus promotes the use of mosquito repellents to prevent infectious diseases. In New Caledonia, the office of Social and Health Affairs Direction (DASS) approved 4 active substances of insect repellents for personal anti-vector protection, among these para-menthan-3,8-diol or PMD. This joint-project between James Cook University (JCU) and the University of New Caledonia (UNC) aimed to identify essential oil bearing plants within the flora of New Caledonia that can supply significant quantities of PMD or its precursor citronellal. The study subsequently identified the essential oil of Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson of the Myrtaceae family already produced in New Caledonia as an important candidate for the production of PMD. This oil provides a significant amount of citronellal, which after an acid-catalyzed thermal cyclisation hydration sequence leads to a mixture of cis and trans isomers of PMD. On the basis of a published method, a standard operating procedure for the conversion of citronellal to PMD has been provided to a distillery in New Caledonia. The distillery has since produced and marketed this renewable insect repellent

Media freedom in Melanesia: the challenges of researching the impact of national security legislation

Commentary: In a global context of national security anxiety, governments across the world are passing an increasing number of laws in response to terror-related threats. Often, national security laws undermine media freedom and infringe on democratic principles and basic human rights. Threats to media freedom and abuse of journalists are also increasing in Melanesia. This commentary argues that in a regional context of repetitive political coups, failures in governance, high levels of corruption, insurrections, or even media crises, the tensions between national security legislation and media freedom need to be examined cautiously. The authors suggest that strong methodological and theoretical frameworks that allow for serious consideration of cultural practices and protocols will be necessary to conduct research examining these tensions in Melanesia

Microflow photochemistry—photodecarboxylations in microformats

This article summarizes selected examples of intra- and intermolecular photodecarboxylations involving phthalimides in a commercially available dwell device. Compared to batch conditions in a larger chamber reactor, the investigated transformations in the microreactor furnished higher conversions and yields after significantly shorter reaction times. The product qualities were commonly higher under flow conditions thus avoiding the need for further purifications

Editorial: Novel Technologies for Sustainable and Energy-efficient Flow Photochemistry

Due to the development of novel light-sources, methodologies and technologies, photochemistry has seen a remarkable renaissance in academia and industry. Many photochemical investigations are now routinely performed under continuous-flow conditions in purpose-designed reactors. Successful examples of pre-industrial applications have subsequently been developed and realized. Likewise, photocalytic materials can be easily incorporated into reactor channels, thus further advancing the potential of flow-photochemistry. This Research Topic comprises of four submissions and highlights recent achievements in photochemical research

Photochemistry down under: solar chemicals from and for the tropics

The Applied and Green Photochemistry Group at James Cook University (JCU) in Townsville, Australia, has been at the forefront of solar photochemical research and has realized solar transformations from laboratory through to production scales. Located in tropical North Queensland, Townsville experiences over 300 days of sunshine per year, which makes it a favorable location for solar research. The current Solar Chemicals from and for the Tropics initiative of the group builds on both of tropical Australia's abundant natural resources, sunlight and biomass, and utilizes these for the bulk production of commercially and tropically relevant chemicals

Solar chemicals from and for tropical Australia

[Extract] At James Cook University (JCU) in Townsville, Australia, the Applied and Green Photochemistry Group utilizes both of tropical North Queensland's abundant natural resources: sunlight and biomass. The Solar Chemicals from and for the Tropics activities of the group subsequently focus on the production of commercially important commodity chemicals from these materials

Microflow photochemistry: UVC-induced [2 + 2]-photoadditions to furanone in a microcapillary reactor

[2 + 2]-Cycloadditions of cyclopentene and 2,3-dimethylbut-2-ene to furanone were investigated under continuous-flow conditions. Irradiations were conducted in a FEP-microcapillary module which was placed in a Rayonet chamber photoreactor equipped with low wattage UVC-lamps. Conversion rates and isolated yields were compared to analogue batch reactions in a quartz test tube. In all cases examined, the microcapillary reactor furnished faster conversions and improved product qualities

Methyl Oleate Synthesis by TiO2 Photocatalytic Esterification of Oleic Acid: Optimisation by Response Surface Quadratic Methodology, Reaction Kinetics and Thermodynamics

Methyl oleate, an example of a FAME (fatty acid methyl ester), was produced by oleic acid (OA) photoesterification with TiO2 and UVA light. Different parameters were evaluated and optimised: catalyst pretreatment, temperature (25–65°C), catalyst loading (1–30 % w/wOA) and oleic acid : alcohol molar ratio (1 : 3–1 : 55). Response surface quadratic methodology obtained by central composite rotational design (RSM-CCRD) was used to evaluate the main operational conditions of the photoesterification process. A high conversion of 98 % (±0.8) at 55 °C, 20 % TiO2 (w/wOA), and 1(OA) : 55(methanol) molar ratio was achieved. The photoesterification mechanism is furthermore proposed. The Langmuir-Hinshelwood kinetic model considered the forward and backward reaction as first-order fits with the best accuracy (R2 of 0.997). The thermodynamic results (ΔG338.15K=−20.75 kJ/mol, ΔH=13.75 kJ/mol, and ΔS=0.47 kJ/mol.K) indicate that the operating conditions are important, both to supply the energy requirement of the reaction, but also to increase the miscibility of the reactants

Isothiazoles and Disease-Controlling Agent

PROBLEM TO BE SOLVED: To provide new compounds exhibiting high effect as a plant-controlling agent and having higher safety. SOLUTION: The present invention relates to isothiazoles represented by formula (I) [wherein A is an alkylene which may be substituted by a cycloalkyl, or a cycloalkylidene; R is a phenyl which may be substituted (wherein substituent groups are 1 to 5 groups selected from a group consisting of a halogen, an alkyl, an alkenylene, an alkoxy, a phenoxy, an alkylthio, a haloalkyl, a haloalkoxy, a haloalkylthio, phenyl and nitro)]

A compact photomicroreactor design for kinetic studies of gas-liquid photocatalytic transformations

A compact photomicroreactor assembly consisting of a capillary microreactor and small-scale LEDs was developed for the study of reaction kinetics in the gas-liquid photocatalytic oxidation of thiophenol to phenyl disulfide within Taylor flow. The importance of photons was convincingly shown by a suction phenomenon due to the fast consumption of oxygen. Mass transfer limitations were evaluated and an operational zone without mass transfer effects was chosen to study reaction kinetics. Effects of photocatalyst loading and light sources on the reaction performance were investigated. Reaction kinetic analysis was performed to obtain reaction orders with respect to both thiophenol and oxygen based on heterogeneous and homogeneous experimental results, respectively. The Hatta number further indicated elimination of mass transfer limitations. Reaction rate constants at different photocatalyst loadings and different photon flux were calculated. Furthermore, the advantages of this photomicroreactor assembly for studying gas-liquid photocatalytic reaction kinetics were demonstrated as compared with batch reactors. This article is protected by copyright. All rights reserved