Axion-like particle oscillations

String theory compactifications may generate many light axion-like particles (ALPs) with weak couplings to electromagnetism. In general, a large number of ALPs may exist, with a linear combination having a potentially observable coupling to electromagnetism. The basis in which only one ALP couples to electromagnetism is in general misaligned with the mass basis. This leads to mixing between the `electromagnetic' ALP and a number of `hidden' ALPs that do not interact directly with the photon. The process is analagous to neutrino oscillations. I will discuss the phenomenological consequences of this mixing for astrophysical ALP signals, in particular showing that it may significantly reduce the predicted signal in experiments such as the CERN Axion Solar Telescope.

Volume change in compacted claystone-bentonite mixtures as affected by the swamp acidic water

Water containing sulfuric acid with a pH up to 3 is prevalent in swampy areas. This article focuses on the effects of the solution on volume change of compacted claystone?bentonite mixture. Claystone was obtained from Banjarbakula landfill and it was mixed with bentonite on a 5, 10, 15, and 20% dry mass basis. Samples possessed the dry density of 16 kN/m3 and moisture content of 10, 15, and 20%. The odometer examined the samples' swelling and compression in both pure and acidic water. Characterization tests i.e., XRF, XRD, and FTIR were also performed. The results showed that swelling and compression were affected by initial moisture and bentonite content. Samples with a moisture content of 20% showed compression in acidic water. Acidic water changed the water absorbed on the clay surface without altering the mineral. A mixture containing 20% bentonite compacted to optimum moisture content was found at best in reducing the acidic water effects.

Assessment of Food Quality and Safety of Cultivated Macroalgae

Macroalgae aquaculture is 16 times larger than fish on a mass basis, making macroalgae by far the largest group of aquacultured products [...]

Individual Psychology and Grand StrategyRomancing the State

Individual psychology at the both mass and elite levels is potentially relevant for grand strategy, but its impact is very difficult to establish. This chapter first reviews the epistemological challenges of showing individual agency in international politics in a way that satisfies “positivist” criteria for good social science. It then turns to how these problems are particularly pronounced for establishing how and why leaders matter for grand strategy, which likely explains why there is so little research on the subject. The piece makes the case for a turn away from the substance of grand strategy towards a focus on leadership style, introducing a distinction between realists and romantics. These two leadership styles emerge out of fundamentally different patterns of cognition: romantics are marked by their emotional, intuitive, and less procedurally rational psychology and realists by their deliberative and objective thinking style. Romantics are also better positioned, and more likely, to make the kind of appeals to public opinion that provide a mass basis for a grand strategy.

Energy Analysis of Greenhouse Dryer for Ficus Carica L. Leaves

In this study, a greenhouse solar dryer with double-pass multi-hollow collector for leaf drying was design, constructed, and evaluated. From the result, the double pass solar air collector with multi-hollow tube is capable of increasing air temperature by 5.5℃-10.8℃ compared to ambient air temperature. Thermal efficiency of the dryer was evaluated for passive and active modes, where 47.2% and 50% are recorded respectively. The moisture reduction on mass basis in passive and active dryer recorded was 44% and 74%, respectively. The specific moisture extraction rate (SMER) and specific energy consumption (SEC) of passive dryer was determined to be 0.198 kg per kWh and 5.047 kWh per kg, and active dryer at 0.210 kg per kWh and 4.769 kWh per kg, respectively.

Effects of core splice joint width on the performance of composite sandwich structures with honeycomb core: An experimental study

Composite sandwich structures are commonly considered in large-scale aerospace applications due to their performance on a per mass basis. The nature of a large-scale sandwich structure generally necessitates the use of multiple sections of core to fill out the structural form. These core sections must be spliced together to ensure that shear loads are appropriately transmitted throughout the core. Because core installation in a large-scale component is a challenging operation, core splice joint width can be difficult to control in manufacturing. As such, the effects of core splice joint width on sandwich structure performance should be well understood. This study examines the effects of core splice joint width in honeycomb sandwich structures via mechanical testing and post-failure analysis. A threshold core splice joint width is shown to exist with respect to core shear, while the integrity of the facesheet-to-core interface is shown to degrade with increasing core splice joint width.

Volatile organic compound fluxes over a winter wheat field by PTR-Qi-TOF-MS and eddy covariance

Volatile organic compounds (VOC) contribute to air pollution through the formation of secondary aerosols and ozone and contribute to increasing the lifetime of methane in the atmosphere. Tropospheric VOC are 90 % originating from biogenic sources at the global scale. Forests are the main contributors to these emissions with isoprene and monoterpenes being the most emitted compounds. Crops are also a potentially large, yet poorly characterised, source of VOC. In particular, measurements of VOC fluxes for wheat at the ecosystem scale are scarce, although this is the most cultivated crop in Europe. Available evidence indicates that crops may contribute to 30% of the VOC emissions in Europe, especially oxygenated, low-molecular-weight VOC such as methanol, acetone and acetaldehyde. In this study, which is part of the COV3ER French national project, we investigated VOC fluxes over a wheat field in-situ by eddy covariance using a PTR-Qi-TOF-MS with an outmost sensitivity and mass resolution. We found 264 compounds to have a flux three times above the flux detection limit. Methanol was the most emitted compound, with an averaged flux of 63 µg m−2 h−1, representing around 60 % of summed VOC emissions on a molar basis (40 % on a mass basis). This finding is in line with previous measurements at canopy and plant scales. We also measured acetone, acetaldehyde and dimethyl sulphide among the five most emitted compounds. The second most emitted VOC corresponded to the ion m/z 93.037, tentatively identified as C6H4O. This compound was not reported previously as one of the most emitted compound by terrestrial ecosystems. Summed VOC emissions amounted around 150 µg m−2 h−1. Summed VOC deposition amounted to around −125 µg m−2 h−1, which represented about 70 % of the VOC emissions on a mass basis. The most depositing VOC were tentatively identified as hydroxyacetone and fragments of oxidised VOC with a flux of −16 µg m−2 h−1. Overall, our results reveal that wheat fields represent a non-negligible source and sink of VOC to be considered in regional VOC budgets, and underline the usefulness and limitations of eddy covariance measurements with PTR-Qi-TOF-MS.