Hybrid Cements. Mechanical Properties, Microstructure and Radiological Behavior

The use of more eco-efficient cements in concretes is one of the keys to ensuring construction industry sustainability. Such eco-efficient binders often contain large but variable proportions of industrial waste or by-products in their composition, many of which may be naturally occurring radioactive materials (NORMs). This study explored the application of a new gamma spectrometric method for measuring radionuclide activity in hybrid alkali-activated cements from solid 5 cm cubic specimens rather than powder samples. The research involved assessing the effect of significant variables such as the nature of the alkaline activator, reaction time and curing conditions to relate the microstructures identified to the radiological behavior observed. The findings showed that varying the inputs generated pastes with similar reaction products (C-S-H, C-A-S-H and (N,C)-A-S-H) but different microstructures. The new gamma spectrometric method for measuring radioactivity in solid 5 cm cubic specimens in alkaline pastes was found to be valid. The variables involved in hybrid cement activation were shown to have no impact on specimen radioactive content. The powder samples, however, emanated 222Rn (a descendent of 226Ra), possibly due to the deformation taking place in fly ash structure during alkaline activation. Further research would be required to explain that finding.

A mass spectrometric method for in-depth profiling of phosphoinositide regioisomers and their disease-associated regulation

Phosphoinositides are a family of membrane lipids essential for many biological and pathological processes. Due to the existence of multiple phosphoinositide regioisomers and their low intracellular concentrations, profiling these lipids and linking a specific acyl variant to a change in biological state have been difficult. To enable the comprehensive analysis of phosphoinositide phosphorylation status and acyl chain identity, we develop PRMC-MS (Phosphoinositide Regioisomer Measurement by Chiral column chromatography and Mass Spectrometry). Using this method, we reveal a severe skewing in acyl chains in phosphoinositides in Pten-deficient prostate cancer tissues, extracellular mobilization of phosphoinositides upon expression of oncogenic PIK3CA, and a unique profile for exosomal phosphoinositides. Thus, our approach allows characterizing the dynamics of phosphoinositide acyl variants in intracellular and extracellular milieus.

An Inductively Coupled Plasma Optical Emission Spectrometric Method for the Determination of Toxic and Nutrient Metals in Spices after Pressure-Assisted Digestion

The aim of this study was to develop a simple and rapid inductively coupled plasma optical emission spectrometric (ICP-OES) method for the determination of 17 metals (Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Tl and Zn) in packaged spices. For this purpose, the spice samples (200 mg) in the form of powder were submitted to pressure-assisted wet-acid digestion with a mixture of 6 mL concentrated HNO3 and 1 mL H2O2. The proposed method was validated in terms of linearity, trueness, precision, limits of detection (LODs) and limits of quantification (LOQs). Good method trueness, precision and linearity were observed for the examined elements. The LODs of the examined analytes ranged between 0.08 and 5.95 mg kg−1. The present method was employed for the analysis of twenty-two packaged commercially available spices including asteroid anise, clove, cardamon, cinnamon, curry, coriander, turmeric, cumin, white pepper, black pepper, nutmeg, allspice, red pepper, paprika, ginger, green pepper and pink pepper from the Greek market that are widely consumed. A wide variety of metal of different concentration ranges were determined in the samples.

Comparative study the essential oil composition of flowers and leaves of Crataegus monogyna L.

The aim of the work was to obtain essential oil from the leaves and flowers of the genus Hawthorn Crataegus monogyna L. and study its component composition to justify the possibility of expanding the use of this herbal drugs in medicine. Materials and methods. The leaves and flowers of Сrataegus monogyna L., which were used to obtain essential oil, were harvested in the western region of Ukraine in 2019. The quantitative content of essential oil in the herbal drugs was determined by hydrodistillation. By used chromato-mass spectrometry method determined the component composition of essential oil of leaves and flowers of Сrataegus monogyna L. The obtained spectra were compared with the library of mass spectra NIST05 and WILEY 2007 with a total number of spectra over 470000 in combination with programs for identification AMDIS and NIST.Results. The essential oil of leaves and flowers of Сrataegus monogyna L. was obtained and its quantitative content was determined, which was 0.15±0.02 % for flowers and 0.11±0.03 % for leaves. By used chromato-mass spectrometric method in the essential oil of flowers of Сrataegus monogyna L. revealed 37 compounds, leaves – 33. In the essential oil of flowers found monoterpenoids, the content of which was 0.44 % of the total, triterpenoids 7.17 %, aromatic compounds 12.61 %. In the essential oil of leaves were found monoterpenoids 37.8 %, aromatic compounds 10.25 %, norterpenoids 3.62 %, sesquiterpenoids 4.02 %, diterpenoids 2.17 %, triterpenoids 5.08 %.Conclusions. Due to the defined component composition of the essential oil of flowers and leaves of Сrataegus monogyna L., we consider its use to create drugs of external action for the treatment of skin diseases of various etiologies caused by staphylococcal and fungal microflora.

VALIDATED STABILITY INDICATING SPECTROSCOPIC METHOD FOR ESTIMATION OF DEGRADATION BEHAVIOUR OF VALSARTAN AND HYDROCHLOROTHIAZIDE IN TABLET FORMULATION

A simple, accurate and precise UV spectrometric method has been developed for the simultaneous determination of valsartan and hydrochlorothiazide in tablet dosage form. Spectra of valsartan and hydrochlorothiazide in methanol and water (50:50 V/V) show λ max at 250.0 nm and 271.4 nm, respectively. Valsartan and hydrochlorothiazide are subjected to various stress conditions like acid, alkali, thermal and photolytic degradation. Beer’s law was obeyed in concentration range of 4- 24 µg mL-1 for valsartan and 0.5-3 µg mL-1 for hydrochlorothiazide at their respective wavelengths. The proposed method was successfully applied to tablet dosage form for determination of both drugs. The percentage recovery of valsartan and hydrochlorothiazide were found to be 100.19 % and 99.51 %, respectively. A novel accurate and precise stability indicating spectroscopic method has been developed for estimation of valsartan and hydrochlorothiazide.

Single source-based energy and efficiency calibration method for the assessment of an alpha imaging detector

An alpha imaging detector acquires a two-dimensional distribution of a sample that emits alpha particles. For the quantitative analysis of the image of an alpha-emitting sample, the individual energies of the alpha particles must be identified, which can be achieved using the spectrometric method after detector calibration. In this study, an energy and efficiency calibration method was investigated to assess an alpha imaging detector. The calibration was performed using a single standard source of Am-241 based on the energy loss characteristic of an alpha particle. The feasibility of the calibration method was evaluated using another source, Ac-225. The calibrated alpha imaging detector was evaluated in terms of energy resolution and detection efficiency, and the alpha imaging detector was found to be efficiently calibrated using a single standard source. The calibrated alpha imaging detector appears promising for the quantitative analysis of samples that emit alpha particles.