Investigation of Batch Foamer Efficacy and Optimisation in North Sea Gas Condensate Wells

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Analyzing the Periodicity in Proto-Planetary Nebulae

Our research revolved around analyzing how the brightness of proto-planetary nebulae (PPNe) vary over time. The overall goal was to analyze their light curves for periodicity and to find what the periods are. PPNe are celestial objects in transition from the red giant phase to the planetary nebula phase of a star’s life cycle, a phase that only lasts a few thousand years. PPNe are known to pulsate, causing them to periodically vary in brightness, and these pulsations can be observed and analyzed in their light curves. To analyze our PPNe for periodicity, we gathered data from the online database of a sky survey named ASAS-SN, which surveys the skies every clear night. The observational data stretch back to 2016. After reducing the data, we analyzed it using a program called Period04, which uses a Fourier transform to search for periods and allowed us to fit sine curves to the data. We studied a sample of 14 PPNe located in the southern hemisphere. We found that most have periods ranging from around 20 - 103 days, with several PPNe having multiple periods. The general pattern was that most of those PPNe have two periods that are within 10% of each other, forming beat periods in the amplitudes. Two PPNe also have longer period modulations of 1000 to 2000 days. This research was supported by a grant from the Indiana Space Grant Consortium

Efficient Photon Upconversion Enabled by Strong Coupling Between Organic Molecules and Quantum Dots

Hybrid structures formed between organic molecules and inorganic quantum dots can accomplish unique photophysical transformations by taking advantage of their disparate properties. The electronic coupling between these materials is typically weak, leading photoexcited charge carriers to spatially localize to a dot or a molecule at its surface. However, we show that by converting a chemical linker that covalently binds anthracene molecules to silicon quantum dots from a carbon-carbon single bond to a double bond, we access a strong-coupling regime where excited carriers spatially delocalize across both anthracene and silicon. By pushing the system to delocalize, we design a photon upconversion system with a higher efficiency (17.2%) and lower threshold intensity (0.5 W/cm^2) than that of a corresponding weakly-coupled system. Our results show that strong coupling between molecules and nanostructures achieved through targeted linking chemistry provides a new route for tailoring properties in materials for light-driven applications.Comment: 33 pages (20 in main text, 13 in supporting information), 12 figures (5 in main text, 7 in supporting information

Toward a Generalizable Framework of Disturbance Ecology Through Crowdsourced Science

© 2021 Graham, Averill, Bond-Lamberty, Knelman, Krause, Peralta, Shade, Smith, Cheng, Fanin, Freund, Garcia, Gibbons, Van Goethem, Guebila, Kemppinen, Nowicki, Pausas, Reed, Rocca, Sengupta, Sihi, Simonin, Słowiński, Spawn, Sutherland, Tonkin, Wisnoski, Zipper and Contributor Consortium.Disturbances fundamentally alter ecosystem functions, yet predicting their impacts remains a key scientific challenge. While the study of disturbances is ubiquitous across many ecological disciplines, there is no agreed-upon, cross-disciplinary foundation for discussing or quantifying the complexity of disturbances, and no consistent terminology or methodologies exist. This inconsistency presents an increasingly urgent challenge due to accelerating global change and the threat of interacting disturbances that can destabilize ecosystem responses. By harvesting the expertise of an interdisciplinary cohort of contributors spanning 42 institutions across 15 countries, we identified an essential limitation in disturbance ecology: the word ‘disturbance’ is used interchangeably to refer to both the events that cause, and the consequences of, ecological change, despite fundamental distinctions between the two meanings. In response, we developed a generalizable framework of ecosystem disturbances, providing a well-defined lexicon for understanding disturbances across perspectives and scales. The framework results from ideas that resonate across multiple scientific disciplines and provides a baseline standard to compare disturbances across fields. This framework can be supplemented by discipline-specific variables to provide maximum benefit to both inter- and intra-disciplinary research. To support future syntheses and meta-analyses of disturbance research, we also encourage researchers to be explicit in how they define disturbance drivers and impacts, and we recommend minimum reporting standards that are applicable regardless of scale. Finally, we discuss the primary factors we considered when developing a baseline framework and propose four future directions to advance our interdisciplinary understanding of disturbances and their social-ecological impacts: integrating across ecological scales, understanding disturbance interactions, establishing baselines and trajectories, and developing process-based models and ecological forecasting initiatives. Our experience through this process motivates us to encourage the wider scientific community to continue to explore new approaches for leveraging Open Science principles in generating creative and multidisciplinary ideas.This research was supported by the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), as part of Subsurface Biogeochemical Research Program’s Scientific Focus Area (SFA) at the Pacific Northwest National Laboratory (PNNL). PNNL is operated for DOE by Battelle under contract DE-AC06-76RLO 1830

Modernization of the Hilger and Watts Guage-block Interferometer

The Hilger & Watts gauge-block interferometer was designed and manufactured commercially in the 1950s. The instrument uses isotope lamps as wavelength standards to perform absolute length calibration of gauge blocks (slip gauges) up to 100 mm in length, to an accuracy of approximately 1 ppm. It is entirely manually operated. In order to make the instrument more suitable for the modern laboratory, new hardware has been added, and a customized software package developed to automate the measurement process. This paper shows how interferograms may be imaged successfully at each of the eight available wavelengths, and the critical fringe fraction measurement automated, ensuring an accuracy better than ±0.05 fringe. To demonstrate the validity of the new system, representative data are presented alongside data obtained using the traditional method and from an external accredited laboratory

Effects of Sound Interventions on the Permeability of the Blood–Brain Barrier and Meningeal Lymphatic Clearance

The meningeal lymphatic, or glymphatic, system is receiving increasing attention from the scientific community. Recent work includes noninvasive techniques to demonstrate relationships between blood–brain barrier (BBB) activity and the glymphatic system in the human central nervous system. One potential technique is the use of music/sound to enhance BBB permeability regarding the movement of small molecules in and out of the brain. However, there is minimal knowledge regarding the methodical investigation(s) of the uses of music/sound on BBB permeability and glymphatic clearance and the outcomes of these investigation(s). This review contains evidence discussing relationships between music/sound, BBB permeability, and meningeal lymphatic clearance. An overview of the anatomy and physiology of the system is presented. We discuss the uses of music/sound to modulate brain and body functions, highlighting music’s effects on mood and autonomic, cognitive, and neuronal function. We also propose implications for follow-up work. The results showed that music and sound interventions do, in fact, contribute to the opening of the BBB and subsequently increase the function of the meningeal lymphatic system. Evidence also suggests that music/sound has the ability to reduce the collateral effects of brain injuries. Unfortunately, music/sound is rarely used in the clinical setting as a medical intervention. Still, recent research shows the potential positive impacts that music/sound could have on various organ systems

Variability in Protoplanetary Nebulae. VIII. A New Sample of Southern Hemisphere Objects

As part of our continuing study of light variability in protoplanetary nebulae (PPNe), we present the results from a long-term study of nine southern hemisphere objects. We have monitored their light variations over a nine-year interval from 2010 to 2018. These were supplemented by data from the ASAS-SN and ASAS-3 surveys, leading to combined light curves from 2000 to 2020. Pulsation periods were found in seven of the objects, although the three shortest must be regarded as tentative. The periods range from 24 to 73 days. When compared with the results of previous studies of the light variations in PPNe, we find that they show the same trends of shorter period and smaller light variations with higher temperatures. Luminosities were calculated based on the spectral energy distributions, reddening, and Gaia distances, and these confirm the identification of all but one as post-AGB objects. Three of the stars possess long-period variations of 5-19 yr. These are most likely due to the periodic obscuration of the star by a disk, suggesting the presence of a binary companion and a circumbinary disk

Nano-Minerals Plus Higher Temperatures Accelerate the Release and Transport of Carbon from Sediment

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