Kinetic and Thermodynamic Aspects of the Degradation of Ferritic Steels Immersed in Solar Salt.

The study and improvement of the corrosion resistance of materials used in concentrated solar power plants is a permanent field of research. This involves determining their chemical stability when in contact with heat transfer fluids, such as molten nitrate salts. Various studies indicate an improvement in the corrosion resistance of iron-based alloys with the incorporation of elements that show high reactivity and solubility in molten nitrate salts, such as Cr and Mo.

Insight into the Corrosion Inhibition Performance of Leaf Extract as a Novel Eco-Friendly Corrosion Inhibitor for Mild Steel in 1 M HCl Solution.

In this research, the leaf (PSL) extract was evaluated as a green corrosion inhibitor for the corrosion of mild steel in 1 M HCl using electrochemical measurements and surface characterization. Electrochemical impedance spectroscopy (EIS) spectra showed that the inhibitory activity of the phytochemical compounds enhanced with increasing concentration up to 400 ppm, which was reflected in the increase in the charge transfer resistance and double-layer capacitance. Regarding the effect of immersion time, EIS results indicated that the persistence of the PSL extract was between 4 h and 8 h of exposure time.

Injector port acylation of γ-hydroxybutyrate (GHB): Condition optimisation, source adjustments, and characterisation of the derivatives.

For several years, gas chromatography-mass spectrometry (GC-MS) has been used to identify gamma-hydroxybutyrate (GHB) in forensic toxicology cases. However, under injector port conditions GHB can dehydrate into gamma-butyrolactone (GBL). Therefore, it is important for GHB to undergo a derivatisation reaction before an analysis to avoid the production of GBL; various analytical methods have been developed for the analysis of GHB but very few methods use acylation as a form of derivatisation.

Selective and highly sensitive measurement of HO and organic hydroperoxides with PtNP/Poly(Brilliant Green)/SPCE.

This research presents a novel electrochemical approach for the selective measurement of hydrogen peroxide and organic hydroperoxides, which is pivotal in many fields. The study details the development of an advanced sensor using a one-pot, one-step synthesis to embed platinum nanoparticles within a 3D-polymeric matrix of poly (brilliant green) on screen-printed carbon electrodes. The modified surfaces were characterized using scanning and transmission electron microscopy, Raman spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy.

5q14.3 Microdeletion Syndrome With Simultaneous Involvement of MEF2C and RASA1. Clinical Case and Review of the Literature.

5q14.3 microdeletion syndrome is a rare condition involving multiple genes such as MEF2C and RASA1 and is potentially classified as a neurocutaneous syndrome. Deletion of the MEF2C gene accounts for the majority of clinical manifestations, including global developmental delay, intellectual disability, seizures, and behavioral disorders.

Hexane extract of Persea schiedeana Ness as green corrosion inhibitor for the brass immersed in 0.5 M HCl.

The hexane extract of Persea schiedeana Ness (PSN) was analyzed as corrosion inhibitor for the brass surface immersed in 0.5 M HCl. Fourier-transform infrared spectroscopy and a gas chromatographic (GC) and mass spectrometric (MS) were used to identify the PSN extract's functional groups and compound constituents.

Comparison of the Analgesic Efficacy between Levobupivacaine 0.25% and Ropivacaine 0.375% for PENG (Pericapsular Nerve Group) Block in the Context of Hip Fracture Surgery of Elderly Patients: A Single-Center, Randomized, and Controlled Clinical Trial.

Previous studies have compared levobupivacaine versus ropivacaine in various peripheral nerve blocks in terms of block duration, quality of analgesia, and onset time, but this has not occurred in the PENG block. Here, a single-center, randomized, and controlled clinical trial is presented. One hundred and twenty patients older than 65 years suffering from hip fractures and surgically treated at our institution under spinal anesthesia were eligible for participation; of them, one hundred and eight were analyzed.

Identifying and locating carotenoids in supra-orbital combs of male black grouse (Lyurus tetrix) using Raman and transmission electron microscopy: A histological study using rehydrated tissue samples.

Colourful signals have long been implicated as indicators of individual quality in animals. Bare-skin signals are an understudied aspect of avian colouration compared with plumage studies, despite displaying rapid changes in size and colour in response to different environmental or physiological stressors. Even fewer studies have focused on the underlying histology of these structures and the importance this plays in the resulting skin colour.

Non-invasive characterization of the elastic protein resilin in insects using Raman spectroscopy.

Resilin is an extremely efficient elastic protein found in the moving parts of insects. Despite many years of resilin research, we are still only just starting to understand its diversity, native structures, and functions. Understanding differences in resilin structure and diversity could lead to the development of bioinspired elastic polymers, with broad applications in materials science.

A smart chitosan-graphite molecular imprinted composite for the effective trapping and sensing of dimethyl methylphosphonate based on changes in resistance.

A molecular imprinted polymer (MIP) fabricated from a chitosan doped with graphite to create a conductive composite (CG-MIC) with the ability to trap and detect dimethyl methylphosphonate (DMMP) through a change in resistance of the material has been successfully manufactured. The GC-MIC presented a maximum trapping capacity of 96 ppm (0.096 mg g) of DMMP.

Mechanistic Study of Arsenate Adsorption onto Different Amorphous Grades of Titanium (Hydr)Oxides Impregnated into a Point-of-Use Activated Carbon Block.

Millions of households still rely on drinking water from private wells or municipal systems with arsenic levels approaching or exceeding regulatory limits. Arsenic is a potent carcinogen, and there is no safe level of it in drinking water. Point-of-use (POU) treatment systems are a promising option to mitigate arsenic exposure.

The chemistry of an insect ear: ionic composition of a liquid-filled ear and haemolymphs of Neotropical katydids.

The purpose of this study is to examine and to compare the ionic composition of the haemolymph and the ear fluid of seven species of katydids (Orthoptera: Tettigoniidae) with the aim of providing from a biochemical perspective a preliminary assessment for an insect liquid contained in the auditory organ of katydids with a hearing mechanism reminiscent of that found in vertebrates. A multi-element trace analysis by inductively coupled plasma optical-emission spectrometry was run for 16 elements for the ear liquid of seven species and the haemolymph of six of them. Based on the obtained results, it can be recognized that the ionic composition is variable among the studied insects, but sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) are the most prominent of the dissolved inorganic cations.

Brain Nocardiosis Defined by 18 F-Fluorocholine PET/CT.

Nocardia infection (nocardiosis) is usually acquired by inhalation; so pulmonary nocardiosis is the most common clinical presentation. Extrapulmonary localization occurs through hematogenous dissemination or contiguous spread. Nocardia can involve the central nervous system in a very reduced number of patients, mainly in immunocompromised.

Electropolymerization of Metallo-Octaethylporphyrins: A Study to Explore Their Sensing Capabilities.

The electropolymerization of metallo-octaethylporphyrins (OEP) containing copper, zinc or nickel metal were performed using cyclic voltammetry at three different potential ranges. The electropolymerized porphyrins were characterized by UV-Vis and Raman spectroscopies and the Soret band (393-445 nm) and Raman bands were used to assess the degree of electropolymerization obtained. The application for an analytical use of the modified electrodes to determine phenobarbital in aqueous solution was evaluated.

Behavior of Ni20Cr Alloy in Molten Nitrate Salts.

This study reports the behavior of the Ni20Cr alloy in molten nitrate salts. Its behavior was evaluated in the eutectic mixture called Solar Salt (binary salt) and in a ternary mixture (90% Solar Salt and 10% lanthanum nitrate). The addition of lanthanum nitrate was performed to determine if the presence of the La cation could act as a corrosion inhibitor.

The Production and Evaluation of an Electrochemical Sensors for Strychnine and Its Main Metabolite Strychnine N-Oxide for Their Use in Biological Samples.

Strychnine (STN) and its major metabolite Strychnine N-Oxide (SNO) were examined electrochemically. Both parent compounds and its major metabolite showed electroactivity on glassy carbon electrodes using CV and DPV techniques. One oxidation peak at 1008 mV was observed for STN with the optimum peak intensity at pH 7.

Application of LC-QTOF/MS for the validation and determination of organic explosive residues on Ionscan® swabs.

The identification and confirmation of trace explosive residues along with potential precursors and degradation products require a comprehensive laboratory analysis procedure. This study presents the determination of organic explosives consisting of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,4,6-trinitrotoluene (TNT), 2,4,6,N-tetranitro-N-methylaniline (Tetryl), 1,3,5-trinitrobenzene (1,3,5-TNB) and pentaerythritol tetranitrate (PETN) by a high-resolution liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). The qualitative information including retention time, collision energy, precursor ions, and characteristic fragmentation pattern of each explosive were collected using an atmospheric pressure chemical ionization (APCI) in negative ion mode.

Computational Design of a Molecularly Imprinted Polymer for the Biomonitoring of the Organophosphorous Metabolite Chlorferron.

Coumaphos is an organophosphorus compound used as insecticide and frequently used by beekeepers for the management of parasitic mites. The most important metabolite, chlorferron (CFN), has been identified in biological samples and foodstuff. The need to quickly identify the presence of typical metabolites, as an indication of interaction with coumaphos has driven the need to produce a highly sensitive electrochemical method for chlorferron analysis, based on molecularly imprinting polymers (MIP) technology.

Evaluating residual compressive strength of post-fire concrete using Raman Spectroscopy.

Cement and water within the concrete mass create a hydrated phase which acts as the glue for holding the sand and coarse aggregates in place to develop a strong construction material. The most important phase within the cement matrix is that of calcium silicate hydrate (CSH), which is largely responsible for the concrete strength. Decomposition of the CSH phase due to high temperatures will affect compressive strength of the concrete.

Three-dimensional voltammetry: Use of chronoamperometric E-t-i data to achieve second-order advantage.

This work studied the use of three-dimensional voltammetry, particularly potential-time-current (E-t-i) data, on the development of electroanalytical methods. E-t-i data was obtained by taking chronoamperograms at potentials applied as pulses on a staircase waveform. By using this three-way kind of data and appropriate calibration algorithms, the possibility of achieving the second-order advantage was evaluated in the determination of ferrocyanide in the presence of the uncalibrated interference hydroquinone as a model system.

Challenges in the identification of new thermolabile psychoactive substances: The 25I-NBOH case.

The continuous emergence of NPS over the last years poses a series of novel challenges for forensic analysts. Most of those new compounds are synthesized with minimal chemical modifications to the structure of already known chemicals in order to avoid regulations. Some of these new compounds may undergo chemical changes during analysis leading to misidentification and detrimental legal consequences.

Effective replacement of cetyltrimethylammonium bromide (CTAB) by mercaptoalkanoic acids on gold nanorod (AuNR) surfaces in aqueous solutions.

The highly packed cetyltrimethylammonium bromide (CTAB) bilayer built up on the surface of gold nanorods (AuNRs) when synthesized by the seed-mediated procedure hampers the complete ligand exchange under experimental conditions that preserves the stability of the dispersions. In the present work, a ligand exchange protocol by using carboxy-terminated alkanethiols of different chain lengths by means of a green approach that uses only aqueous solutions is presented. The protocol is based on the knowledge of the stability in the aqueous solution of both the starting CTAB-AuNRs and the final products that help in the choice of the experimental conditions used for ligand exchange.

Classification of ANFO samples based on their fuel composition by GC-MS and FTIR combined with chemometrics.

Ammonium nitrate fuel oil (ANFO) is one of the most favorite explosives used in terrorist attacks. This explosive is a complex mixture of 95-96% ammonium nitrate (AN) and 4-5% liquid hydrocarbons (fuel oil). In this study, we analyze a variety of ANFO explosive mixtures in order to classify their different sources of origin by observing the difference in fuel components.

Electroanalytical identification of 25I-NBOH and 2C-I via differential pulse voltammetry: a rapid and sensitive screening method to avoid misidentification.

25I-NBOH is a new potent serotonin 5-HT2A receptor agonist recently identified in blotter paper seizures. This compound is a thermolabile molecule that undergoes degradation under routine gas chromatography-mass spectrometry analysis leading to misidentification. In this paper, the voltammetric behavior of 25I-NBOH and 2C-I was investigated and their electroanalytical characteristics were determined.