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This study investigates the potential use of phosphomolybdic acid (POM) as an adsorbate for hazardous organic gases (CH3X, where X = F, Cl, and Br). Density functional theory (DFT) is employed to analyze the interaction between POM and the gases. Structural optimization using the TPSSh/Lanl2Dz level of theory is performed to determine the stable configurations. The adsorption energy of CH3X on POM is calculated to understand the adsorption capabilities and identify the most favorable complex. The results show that CH3F/POM has two optimal adsorption sites, while CH3Br/POM has a larger bond distance and stronger adsorption energy. CH3Cl/POM exhibits three bonding sites. The HOMO-LUMO energy difference decreases after binding, indicating improved conductivity. QTAIM, bond order, and NCI analysis reveal the inter- and intramolecular interactions and bond characteristics. Overall, POM is found to be suitable for adsorbing these gases, especially CH3Br. [ABSTRACT FROM AUTHOR]

Background: Pott's Puffy tumor (PPT) is a complicated frontal sinusitis that is also described as frontal bone osteomyelitis and a localized sub periosteal abscess. Early diagnosis and immediate active treatment are necessary to prevent severe neurologic sequelae. Case Presentation: Here, we report on a case of Pott's puffy tumor in a previously healthy 13-year-old girl with a worsening headache and swelling of the frontal bone accompanied by vomiting and fever. Magnetic resonance imaging revealed osteomyelitis of the frontal bone. A foreign body was discovered and removed via endoscopy which was then followed by 6 weeks of parenteral and enteral antibiotic therapy, resulting in resolution of all symptoms. Conclusion: A complete history in terms of trauma and insect bite or foreign body in the nose is paramount for a correct diagnosis, and performing a full examination of ear, nose and throat (ENT) to rule out a foreign body is advised. [ABSTRACT FROM AUTHOR]

In this paper, we have theoretically determined the possibility of adsorption of the gaseous C[H.sub.2][N.sub.2] molecule on the surface of [X.sub.12][Y.sub.12] nanocages, where X = B, Al, Ga and Y = N, P, As. The electronic structure calculations have been performed by density functional theory (DFT) using four functionals (i.e., B3LYP-D3, M06-2X, [omega]B97XD, and CAM-B3LYP), together with the 6-311G(d) basis function. We find that the adsorption of C[H.sub.2][N.sub.2] on top of the X-Y bond of the nanocage is the most preferred site for adsorption. The adsorption process is accompanied by a charge-transfer phenomenon, which results in a strong bond between the terminal N atom of diazomethane and the X atom of the nanocage. This gives rise to significant changes in the highest and lowest occupied molecular orbital (HOMO and LUMO, respectively) energies and thus attribute properties to the nanocages that enable them to act as building blocks of C[H.sub.2][N.sub.2] sensing materials. Key words: diazomethane, nanocage, DFT, NBO, QTAIM. Dans le cadre des présents travaux, nous avons réalisé une étude théorique pour déterminer la possibilité d'adsorption de la molécule de diazométhane (C[H.sub.2][N.sub.2]) gazeux à la surface de nanocages de formule [X.sub.12][Y.sub.12], où X = B, Al, Ga et Y = N, P, As. Nous avons modélisé la structure électronique selon des calculs de la théorie de la fonctionnelle de la densité (DFT), dans lesquels nous avons utilisé quatre fonctionnelles (soit B3LYPD3, M062X, xB97XD et CAMB3LYP) ainsi que la base 6311G(d). Nos résultats montrent que la liaison X-Y de la nanocage est le site d'adsorption privilégié du C[H.sub.2][N.sub.2]. Le processus d'adsorption est accompagné d'un phénomène de transfert de charge, qui se traduit par une forte liaison entre l'atome d'azote terminal du diazométhane et l'atome X de la nanocage. Ce phénomène donne lieu à des changements importants dans les énergies des orbitales moléculaires frontières (HOMO et LUMO) et confère donc aux nanocages des propriétés qui en font d'éventuels constituants de base pour former des matériaux de détection du C[H.sub.2][N.sub.2]. [Traduit par la Rédaction] Mots-clés : diazomethane, nanocage, théorie de la fonctionnelle de la densité, orbitales naturelles de liaison, théorie quantique des atomes dans les molecules., 1. Introduction Diazomethane (C[H.sub.2][N.sub.2])--ahighly toxic, flammable, and corrosive gas in its pure form at room temperature--can have a number of severe effects upon human health. (1) For example, inhalation of [...]