A diode laser sensor was developed for partial pressure and temperature measurements using a single water vapor transition. The Lorentzian half-width and line intensity of the transition were calibrated for conditions relevant to proton exchange membrane (PEM) fuel cell operation. Comparison of measured and simulated harmonics from wavelength-modulation spectroscopy is shown to yield accuracy of +/-2.5% in water vapor partial pressure and +/-3 degrees C in temperature despite the use of a single transition over a narrow range of temperatures. Collisional half-widths in air or hydrogen are measured so that calibrations can be applied to both anode and cathode channels of a PEM fuel cell. An in situ calibration of the nonlinear impact of modulation on laser wavelength is presented and used to improve the accuracy of the numerical simulation of the signal.
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http://dx.doi.org/10.1364/AO.49.000061 | DOI Listing |
Sci Rep
January 2025
Khuzestan Water & Power Authority (KWPA), Ahvaz, Iran.
Microgrid systems have evolved based on renewable energies including wind, solar, and hydrogen to make the satisfaction of loads far from the main grid more flexible and controllable using both island- and grid-connected modes. Albeit microgrids can gain beneficial results in cost and energy schedules once operating in grid-connected mode, such systems are vulnerable to malicious attacks from the viewpoint of cybersecurity. With this in mind, this paper explores a novel advanced attack model named the false transferred data injection (FTDI) attack aiming to manipulatively alter the power flowing from the microgrid to the upstream grid to raise voltage usability probability.
View Article and Find Full Text PDFNat Commun
January 2025
College of Pharmaceutical Sciences, National Key Laboratory of Advanced Drug Delivery and Release Systems, Zhejiang University, Hangzhou, China.
Nicotinamide (NAM), a main precursor of NAD+, is essential for cellular fuel respiration, energy production, and other cellular processes. Transporters for other precursors of NAD+ such as nicotinic acid and nicotinamide mononucleotide (NMN) have been identified, but the cellular transporter of nicotinamide has not been elucidated. Here, we demonstrate that equilibrative nucleoside transporter 1 and 2 (ENT1 and 2, encoded by SLC29A1 and 2) drive cellular nicotinamide uptake and establish nicotinamide metabolism homeostasis.
View Article and Find Full Text PDFAnal Chem
January 2025
School of Architecture and Civil Engineering, Northeast Petroleum University, Daqing 163318, China.
Multithermal fluid (MTF) component ratios and injection parameters are critical inputs in offshore heavy oil development, such as injection adjustment and monitoring, productivity prediction, and generator combustion process optimization. We implement simultaneous in situ diagnostics of two emblematic injection parameters, the gas-water ratio (GWR) and noncondensable gases proportion (NCGP), in a pilot-scale environment. A system-level integration of a novel laser absorption spectroscopy multigas sensor system based on integrating stray radiation suppression and a circular cell-enhanced strategy is proposed.
View Article and Find Full Text PDFJ Environ Manage
January 2025
School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address:
This review focuses on applying bio-electrochemical systems (BES) for phosphorus (P) recovery. Microbial fuel cells (MFCs) degrade pollutants to generate electricity and recover P, with the structure and electrode materials playing a significant role in P recovery efficiency. Microbial electrolysis cells (MECs) recover P while simultaneously producing hydrogen or methane, with factors such as voltage and pH influencing performance.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
A major challenge in the field of synthetic motors relates to mimicking the precise, motion of biological motor proteins, which mediates processes such as cargo transport, cell locomotion, and cell division. To address this challenge, we developed a system to control the motion of DNA-based synthetic motors using light. DNA motors are composed of a central chassis particle modified with DNA "legs" that hybridize to RNA "fuel", and move upon enzymatic consumption of RNA.
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