Newly published research reveals that the polluted Tijuana River releases large quantities of the toxic gas hydrogen sulfide — commonly known as “sewer gas” because of its association with sewage and rotten egg smell. Scientists measured peak concentrations of hydrogen sulfide that were some 4,500 times what is typical for an urban area. In addition, the paper identifies hundreds of other gases released into the air by the polluted Tijuana River and its ocean outflow, which can contribute to poor air quality across the region.

In addressing the challenges encountered during the design of multi-pass cell (MPC) with dense spot pattern, the research team from Harbin Institute of Technology (HIT) has, for the first time, integrated the parallel non-dominated sorting genetic algorithm II (PNSGA-II) with the mathematical model of MPCs. This innovation has enabled the development of a high-performance multi-pass cell that simultaneously achieves long optical path length and high ratio of optical path length to volume — two key performance metrics that are often mutually restrictive.

Furthermore, the team constructed a light-induced thermoelectric spectroscopy (LITES) sensing system by incorporating a self-designed, high-performance round-head quartz tuning fork (QTF). Leveraging this integrated system, they successfully realized ultra-high sensitivity trace gas detection, with a minimum detection limit (MDL) reaching the ppt (10^-12) level.

Noise is the "ghost in the machine" in the effort to make quantum devices work. Certain quantum devices use qubits—the central component of any quantum processor—and they are extremely sensitive to even small disturbances in their environment.

A collaboration between researchers from the Niels Bohr Institute, MIT, NTNU, and Leiden University has now resulted in a method to effectively manage the noise. The result has been published in PRX Quantum.