Melts of octaacetyl sucrose as oral-modified release dosage forms for delivery of poorly soluble compound in stable amorphous form

The presented work describes the formulation and characterization of modified release glassy solid dosage forms (GSDFs) containing an amorphous nifedipine, as a model BCS (Biopharmaceutical Classification System) class II drug. The GSDFs were prepared by melting nifedipine together with octaacetyl sucrose. Dissolution profiles, measured under standard and biorelevant conditions, were compared to those obtained from commercially available formulations containing nifedipine such as modified release (MR) tablets and osmotic release oral system (OROS). The results indicate that the dissolution profiles of the GSDFs with nifedipine are neither affected by the pH of the dissolution media, type and concentration of surfactants, nor by simulated mechanical stress of biorelevant intensity. Furthermore, it was found that the dissolution profiles of the novel dosage forms were similar to the profiles obtained from the nifedipine OROS. The formulation of GSDFs is relatively simple, and the dosage forms were found to have favorable dissolution characteristics

Spatiotemporal Analysis of Hydration Mechanism in Sodium Alginate Matrix Tablets

Methods of spatiotemporal characterization of nonequilibrated polymer based matrices are still immature and imperfect. The purpose of the study was to develop the methodology for the spatiotemporal characterization of water transport and properties in alginate tablets under hydration. The regions of low water content were spatially and temporally sampled using Karl Fisher and Differential Scanning Callorimetry (spatial distribution of freezing/nonfreezing water) with spatial resolution of 1 mm. In the regions of high water content, where sampling was infeasible due to gel/sol consistency, magnetic resonance imaging (MRI) enabled characterization with an order of magnitude higher spatial resolution. The minimally hydrated layer (MHL), infiltration layer (IL) and fully hydrated layer (FHL) were identified in the unilaterally hydrated matrices. The MHL gained water from the first hour of incubation (5-10% w/w) and at 4 h total water content was 29-39% with nonfreezing pool of 28-29%. The water content in the IL was 45-47% and at 4 h it reached ~50% with the nonfreezing pool of 28% and T2 relaxation time < 10 ms. The FHL consisted of gel and sol layer with water content of 85-86% with a nonfreezing pool of 11% at 4 h and T2 in the range 20-200 ms. Hybrid destructive/nondestructive analysis of alginate matrices under hydration was proposed. It allowed assessing the temporal changes of water distribution, its mobility and interaction with matrices in identified layers

Directions for reducing the energy consumption of mining belt conveyors

W artykule poruszono problematykę oszczędności energii zużywanej przez górnicze przenośniki taśmowe. Wykorzystując pojęcie wskaźnika energochłonności, przedstawiono kierunki ograniczenia zużycia energii przenośników taśmowych przez zastosowanie energooszczędnych podzespołów, modernizację układu napędowego lub wprowadzenie zmian organizacyjno-technicznych w procesie odstawy urobku.The article discusses the issue of energy savings in the operation of mining belt conveyors. Using the concept of energy consumption indicators, the directions for reducing the energy consumption of belt conveyors are presented by applying energy-efficient components, upgrading the drive system, or introducing organizational and technical changes in the conveying process

Kierunki zmniejszenia energochłonności górniczych przenośników taśmowych

The article discusses the issue of energy savings in the operation of mining belt conveyors. Using the concept of energy consumption indicators, the directions for reducing the energy consumption of belt conveyors are presented by applying energy-efficient components, upgrading the drive system, or introducing organizational and technical changes in the conveying processW artykule poruszono problematykę oszczędności energii zużywanej przez górnicze przenośniki taśmowe. Wykorzystując pojęcie wskaźnika energochłonności, przedstawiono kierunki ograniczenia zużycia energii przenośników taśmowych przez zastosowanie energooszczędnych podzespołów, modernizację układu napędowego lub wprowadzenie zmian organizacyjno-technicznych w procesie odstawy urobku

Identification of the operating parameters of the friction drum drive in industrial conditions

The publication presents the results of measurements of the operating parameters of the drum drive of a belt conveyor operating in a copper ore mine. The laboratory and industrial tests of belt conveyor components so far have largely focused on idler sets, the belt and the conveyor route. The authors of the publication notice that the subject literature lacks information on research into the coefficient of friction between the belt and the drum in an industrial facility under real conditions, which may imply that the phenomenon of driving force transmission from the drum surface to the belt has not been thoroughly explored. The investigations described in the publication were aimed at determining the kinetic coefficient of friction between the conveyor belt and the lining of the drive drum under operating conditions. In the first part of the study, preliminary laboratory tests were carried out, whereas in the second part of the study, a mobile, non-invasive measurement system was applied, which allowed for recording the kinematic and dynamic parameters of the conveyor’s operation. During the several dozen minutes of the conveyor’s operation, there were several start-ups and brakings as well as periods of steady operation under variable load on the material handled. The non-typical planned sequence of switching on the drive motors caused a temporary slip of the belt on the drive drum surface during one of the start-ups. The recorded parameters of the conveyor operation enabled determining the operational limit value of the friction coefficient between the belt and the lining of the drive drum