Забезпечення сейсмічного захисту наземних об'єктів на кар'єрах, що видобувають вапняк та гіпс

The paper highlights the research undertaken at three limestone and gypsum quarries belonging to a large cement producer in Romania, in order to evaluate the seismic protection of civil and industrial objectives located near the exploitation perimeters. In this regard, the results obtained from the tests on the determination of seismic parameters are presented, in order to assess the seismic effect generated by the blasting works on civil and industrial objectives located in the vicinity of exploitation areas.У статті висвітлено дослідження, проведене на трьох кар’єрах вапняку та гіпсу, що належать великому виробнику цементу в Румунії, з метою оцінки сейсмічного захисту цивільних та промислових об’єктів, розташованих поблизу периметрів експлуатації. У зв'язку з цим представлені результати, отримані в результаті випробувань з визначення сейсмічних параметрів, з метою оцінки сейсмічного ефекту, що виникає підривними роботами на цивільні та промислові об'єкти, розташовані в районі експлуатаційних зон

High spatial resolution ToF-SIMS imaging and image analysis strategies to monitor and quantify early phase separation in amorphous solid dispersions

Amorphous solid dispersions (ASDs) are formulations with enhanced drug solubility and dissolution rate compared to their crystalline counterparts, however, they can be inherently thermodynamically unstable. This can lead to amorphous phase separation and drug re-crystallisation, phenomena that are typically faster and more dominant at the product’s surfaces. This study investigates the use of high-resolution time of flight-secondary ion mass spectrometry (ToF-SIMS) imaging as a surface analysis technique combined with image-analysis for the early detection, monitoring and quantification of surface amorphous phase separation in ASDs. Its capabilities are demonstrated for two pharmaceutically relevant ASD systems with distinct re-crystallisation behaviours, prepared using hot melt extrusion (HME) followed by pelletisation or grinding: (1) paracetamol-hydroxypropyl methylcellulose (PCM-HPMC) pellets with drug loadings of 10–50% w/w and (2) indomethacin-polyvinylpyrrolidone (IND-PVP) ground material with drug loadings of 20–85% w/w. PCM-HPMC pellets showed intense phase separation, reaching 100% surface coverage within 1-5 months. In direct comparison, IND-PVP HME ground material was more stable with only a moderate formation of isolated IND-rich clusters. Image analysis allowed the reliable detection and quantification of local drug-rich clusters. An Avrami model was applied to determine and compare phase separation kinetics. The combination of chemical sensitivity and high spatial resolution afforded by SIMS was crucial to enable the study of early phase separation and re-crystallisation at the surface. Compared with traditional methods used to detect crystalline material, such as XRPD, we show that ToF-SIMS enabled detection of surface physical instability already at early stages of drug cluster formation in the first days of storage