Background For decades, FTIR spectroscopy has been the method of choice for detecting, identifying, and establishing the purity of chemical compounds based on their infrared absorption properties. The method typically employs a thermal radiation source emitting in the 2.5 to 25 μm spectral range (e.g., GlobarTM ). The light emitted by the source is split into two beams, one of them passing thro...

Hydrogen peroxide ingestion can cause gastric irritation and gas embolism; however, most reported cases are from the highly concentrated (≥35%) solution used in the industry and data on household-used 3% solution ingestion is scarce. We report a case of a portal vein gas embolism after ingestion of 3% hydrogen peroxide. The patient was managed conservatively with antacids and improved in 48 hou...

The model under consideration is an asymmetric two-dimensional Coulomb gas of positively (q1 = +1) and negatively (q2 = −1/2) charged pointlike particles, interacting via a logarithmic potential. This continuous system is stable against collapse of positive-negative pairs of charges for the dimensionless coupling constant (inverse temperature) β < 4. The mapping of the Coulomb gas is made onto ...

Operative planning in gas distribution networks leads to large-scale mixedinteger optimization problems involving a hyperbolic P D E defined on a graph. We consider the N L P obtained under prescribed combinatorial decisions—or as relaxation in a branch and bound framework, addressing in particular the K K T systems arising in primal-dual interior methods. We propose a custom solution algorithm...

In this paper, we propose a new approach to solve the unsteady gas equation. We apply the Modified Laplace decomposition method (MLDM) coupled with Pade ́ approximation to compute a series solution of unsteady flow of gas through a porous medium. The proposed iterative scheme finds the solution without any discretization, linearization or restrictive assumptions. The nonlinear terms can be easil...

Eumelanin is a naturally synthesized ultraviolet light absorbing biomolecule, possessing both photoprotective and phototoxic properties. We infer insight into these properties of eumelanin using a bottom-up approach, by investigating an ultraviolet absorbing motif of eumelanin, 4-tert-butylcatechol. Utilizing a combination of femtosecond transient electronic absorption spectroscopy and time-res...

the michelsen stability and multiphase flash calculation by direct minimization of gibbs free energy of the system at constant temperature and pressure, was used for systems containing gas hydrates. the solid hydrate phase was treated as a solid solution. the fugacities of all components of the hydrate phase were calculated as a function of compositions by the rearranged model of van der waals ...

In an attempt to shed light on the environmental effects on the deactivation channels of the PYP chromophore, radiative and non-radiative deactivation mechanisms of the anionic p-coumaric acid methyl ester (pCE-) in the gas phase and water solution are compared at the CASPT2//CASSCF/cc-pVDZ level and, when necessary, at the CASPT2//CASPT2/cc-pVDZ level. We find that the solvent produces dramati...

the performance of the electric submersible pump (esp) significantly affected by gas void fraction (gvf). thus, using of a rotary gas separator (rgs) is a suitable solution for this issue. the performance of the rgs is function of different parameters such as geometry of impeller, rotating speed, boundary conditions, media viscosity and gvf. in this study, the influences of gvf, viscosity, and ...