Chemical and Physical Ionic Liquids in CO Capture System Using Membrane Vacuum Regeneration.

Carbon Capture Utilization and Storage technologies are essential mitigation options to reach net-zero CO emissions. However, this challenge requires the development of sustainable and economic separation technologies. This work presents a novel CO capture technology strategy based on non-dispersive CO absorption and membrane vacuum regeneration (MVR) technology, and employs two imidazolium ionic liquids (ILs), [emim][Ac] and [emim][MS], with different behavior to absorb CO.

CO Desorption Performance from Imidazolium Ionic Liquids by Membrane Vacuum Regeneration Technology.

In this work, the membrane vacuum regeneration (MVR) process was considered as a promising technology for solvent regeneration in post-combustion CO capture and utilization (CCU) since high purity CO is needed for a technical valorization approach. First, a desorption test by MVR using polypropylene hollow fiber membrane contactor (PP-HFMC) was carried out in order to evaluate the behavior of physical and physico-chemical absorbents in terms of CO solubility and regeneration efficiency. The ionic liquid 1-ethyl-3-methylimidazolium acetate, [emim][Ac], was presented as a suitable alternative to conventional amine-based absorbents.

Acting Role of Background Gas in the Emission Response of Laser-Induced Plasmas of Energetic Nitro Compounds.

This study focuses on the analysis of the optical emission response obtained by laser-induced breakdown spectroscopy from energetic nitro compounds in condensed phase sampled in atmospheres of variable composition. The influence of different background gases was evaluated from the characteristic emissions of the excited species coexisting in the plasma plume and conclusions concerning the main pathways involved in the generation of such emission species were extracted. Different reactive (O2, N2, H2) and inert (Ar, He) gases were tested to establish the comparative emission features of organic compounds.

Pressure effects in laser-induced plasmas of trinitrotoluene and pyrene by laser-induced breakdown spectroscopy (LIBS).

The influence of the ambient atmosphere on the dynamics of plasma expansion, besides the interaction between excited plasma and gas molecules, has been studied for specific organic aromatic compounds. To analyze the influence of air on the formation pathways of atomic and molecular species inside the plasma plume, the spectral emissions in laser-induced breakdown spectroscopy (LIBS) of 2,4,6-trinitrotoluene (TNT) and pyrene were compared at different pressure environments, from high vacuum to atmospheric pressure. Pelletized samples of the compounds were introduced in a vacuum chamber for excitation with the fourth harmonic output of an Nd : YAG laser (266 nm).

Storm sewers as larval habitats for Aedes aegypti and Culex spp. in a neighborhood of Merida, Mexico.

We report the collection of Aedes aegypti, Culex quinquefasciatus, Cx. interrogator, Cx. thriambus, Cx.

Condensed-phase laser ionization time-of-flight mass spectrometry of highly energetic nitro-aromatic compounds.

Rationale: Analysis of explosive compounds represents an interesting field of work due to the obvious social relevance of these compounds. Direct laser ionization allows the analysis of these high internal energy compounds without sampling or preparation procedures. We have studied nitro-aromatic compounds to understand their mass spectra when directly ionized in the condensed phase, different from the gas-phase studies commonly conducted.

Secondary ion mass spectrometry of powdered explosive compounds for forensic evidence analysis.

Rationale: Residual quantities of explosives deposited on, or absorbed in, nearby surfaces can be of forensic value in post-blast analysis. As secondary ion mass spectrometry (SIMS) may be a suitable analytical approach for the screening of such residues, its performance was evaluated.

Methods: The analyses were carried out in a SIMS instrument fitted with a quadrupole analyzer.

Atomic/molecular depth profiling of nanometric-metallized polymer thin films by secondary ion mass spectrometry.

The capability of secondary ion mass spectrometry (SIMS) to perform atomic and molecular in-depth analysis in complex nanometric-metallized thin polymer films used to manufacture capacitors is demonstrated through three different case studies related to failure analysis. The excellent repeatability and sensitivity of the technique allow us to study the degradation process of the nanometric-metallized layer in the capacitor films and the accurate location of the metal-polymer interface. The analysis of the sample is challenging due to the extreme difference in conductivity between layers, and the reduced thickness of the metallization grown on top of a rough polymeric base.

Energy-resolved depth profiling of metal-polymer interfaces using dynamic quadrupole secondary ion mass spectrometry.

Quadrupole secondary ion mass spectrometry (qSIMS) characterization of a metallized polypropylene film used in the manufacturing of capacitors has been performed. Ar(+) primary ions were used to preserve the oxidation state of the surface. The sample exhibits an incomplete metallization that made it difficult to determine the exact location of the metal-polymer interface due to the simultaneous contribution of ions with identical m/z values from the metallic and the polymer layers.

Two-pulse delayed 532-nm laser ionization of metals using collinear sub-threshold beams.

Two frequency-doubled Nd:YAG lasers collinearly aligned were used to ionize different metals at specific interpulse delays. The beams were independently operated in order to attain full control over the energy. Each laser beam was always set at fluences below the ionization threshold and an evaluation of the effect that the interpulse delay has on the material ionization and the LIMS signal was performed.

Remote, real-time, on-line monitoring of high-temperature samples by noninvasive open-path laser plasma spectrometry.

A remote detection system based on optical emission spectrometry of laser-induced plasmas has been developed to record spectra in the visible region from samples placed at remote distances from the excitation source. Unlike from fiber-optic-based systems, light collection is performed remotely as well. Laboratory-scale experiments have shown the possibility of performing real-time analysis of samples placed remotely.

Hadamard transform time-of-flight mass spectrometry: a high-speed detector for capillary-format separations.

This work demonstrates that with an intrinsic duty cycle of 50% and spectral storage speeds up to 277 spectra s(-1) Hadamard transform time-of-flight mass spectrometry (HT-TOFMS) is a promising detector for any capillary-format separation that can be coupled to MS by electrospray ionization. Complete resolution of the components of a nine-peptide standard was achieved by coupling pressurized-capillary electrophoresis (pCE) to HT-TOFMS. The addition of pressure to the separation capillary decreased analysis times and stabilized the electrospray ionization source.