John Chasse

Articles

Optical Detection of Defects during Laser Metal Deposition: Simulations and Experiment

June 23, 2022

Igor Gornushkin and colleagues at BAM Federal Institute for Materials Research and Testing in Berlin, Germany studied the feasibility of using optical spectroscopy as a control method for laser metal deposition, and he recently spoke to us about this work. Gornushkin is the 2022 recipient of the Lester W. Strock Award from the New England Chapter of the Society for Applied Spectroscopy (SAS).

Diagnosis of Gulf War Illness Using Laser-Induced Spectra Acquired from Blood Samples

May 05, 2022

Noureddine Melikechi of the Department of Physics and Applied Physics at the University of Massachusetts (Lowell, MA) saw an urgent need for the development of an untargeted and unbiased method to distinguish Gulf War illness (GWI) patients from non-GWI patients; he and his associates utilized laser-induced breakdown spectroscopy (LIBS) in their efforts to meet that need.

Chemometric Analysis on ATR-FT-IR Spectra of Spray Paint Samples for Forensic Purposes

April 01, 2022

Spray paint is often used by vandals for creating graffiti, as well as for criminals to leave signs, messages, and blots to conceal the left traces at the scene of their efforts. Rajinder Singh and his colleagues in the Department of Forensic Science at Punjabi University (Punjab, India) have used attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy for nondestructive analysis of 20 red spray paints of different manufacturers, which could possibly be encountered at a crime scene, particularly in case of vandalism. Singh spoke to Spectroscopy about the findings, and the paper that resulted from their efforts.

Rapid Detection and Quantification of Plant Innate Immunity Response Using Raman Spectroscopy

February 10, 2022

As global food supplies and security have been challenged by water scarcity and climate variations, the expected increase in food demand will require a corresponding increase in crop productivity and disruptive improvements in agricultural production systems, including implementing strategies to mitigate the degradation of crop yield caused by plant diseases. Several groups have explored the use of Raman spectroscopy for rapid diagnosis of such diseases.

Determination of Elemental Impurities in a Nasal Spray Using ICP-MS

December 07, 2021

A tutorial and spreadsheet for the validation and bottom-up uncertainty evaluation of quantifications performed by instrumental methods of analysis based on linear weighted calibrations were presented by Ricardo J.N. Bettencourt da Silva of the University of Lisbon in Lisbon, Portugal, and colleagues. This software tool was successfully applied to the determination of the mass concentration of Cd, Pb, As, Hg, Co, V, and Ni in a nasal spray by ICP-MS after samples dilution and acidification. Bettencourt da Silva spoke to Spectroscopy about applying this software tool and the implications for a better understanding of quantitative analytical results.

Advances in Table-Top Extreme Ultraviolet Second Harmonic Generation

November 02, 2021

The limited availability of table-top extreme ultraviolet (XUV) sources with adequate fluxes and coherence properties has resulted in a lack of nonlinear XUV and X-ray spectroscopies to free-election lasers (FELs). Michael Zuerch of the Department of Chemistry at the University of California, Berkeley, along with colleagues from ten laboratories across three countries, has conducted the first extreme ultraviolet second harmonic generation (XUV-SHG) experiment above the Ti M edge (32.6 eV), also representing the first table-top demonstration of SHG at photon energies beyond the UV regime.

Combined Spectroscopic Analysis of Terrestrial Analogs from a Simulated Astronaut Mission Using the Laser-Induced Breakdown Spectroscopy (LIBS) Raman Sensor

October 07, 2021

Emmanuel Lalla of York University in Toronto, Ontario, Canada, as well as his co-authors, recently presented an in-depth characterization of a set of samples collected during a 28-day Mars analog mission conducted by the Austrian Space Forum in the Dhofar region of Oman. Lalla spoke to Spectroscopy about this research, as well as how various methods of spectroscopic analysis can complement each other in analysis.

Phonon Imaging in 3D with a Fiber Probe

September 10, 2021

Salvatore La Cavera III and his colleagues in the Faculty of Engineering at the University of Nottingham, in Nottingham, United Kingdom have developed a novel measurement system consisting of two ultrafast lasers that excite and detect high-frequency ultrasound from a nano-transducer fabricated onto the tip of a single-mode optical fiber.

Developing Electrochemical and Optical Sensors to Measure Analytes in Physiological Samples

September 02, 2021

Mark Meyerhoff has been exploring chemical sensors for biomedical applications. Because of his work, Meyerhoff has been awarded the 2021 ANACHEM award. Meyerhoff spoke to us about his work, his career, and what being presented this award at this fall’s SciX event means to him.