Separation of dust particles in the low-pressure pneumatic conveying system

ArticleThis paper focuses on the possibility of separation of dust particle created as a byproduct of technological processing of composite materials. The aim was to design and verify technology for the separation of dust particles from polydisperse granular mixtures, which are created by physical-mechanical processes of materials processing (crushing, sorting, machining or surface treatment of products such as grinding or polishing the surface). Under experimental conditions, a low-pressure pneumatic conveying system was designed and tested in operation, supplemented by a powerful electrostatic dust particles separation system. The entry requirement was to design a system that would be able to work with high separation efficiency using lowpressure suction. The designed separation conveying device consists of three parts: the conveyance section for the grain material suction and conveying, the coarse grain share cyclone separator and the electrostatic precipitator of the dust particles released from the air flow. Operational capacity of the proposed technology was verified by evaluating the separation efficiency of processing the polydisperse granular mixture resulting from the crushing of laser printer toner cartridges. These contain toner powder residues, which are the source of composite dust particles. The separation efficiency of the system was monitored according to the set pressure of the air in front of the electrostatic separator. Evaluation of the results thus obtained confirmed the operational reliability of the system at low-pressure operation and the high separation efficiency of the electrostatic separator under the set operation conditions

Differential thermal regulation of the growth of the bee colonies in the early spring period

ArticleThis paper addresses the issue of the control of activity and growth of the bee colonies (brooding) in the early spring period. The bees are brooding up already in the late winter, and the intensity of brooding in this period is determined by daytime tempe ratures and sunshine hours that increase the temperature of the inner hive space. The objective is to design and verify a technology that would ensure the conditions for the optimal brooding in the early spring period and thus the numerically strong bee co lonies. The experimental part was based on the temperature regulation in the inner hive space. A preset temperature was maintained inside the hive by an electric heating system with regulation. A differential thermal regulation which enabled the optimal gr owth of the bee colonies in accordance with the phenophases was chosen for verification. To verify the proposed method, two groups of the bee colonies were assembled. One group of the bee colonies had a heating system with regulation installed inside the h ive. The second group of the bee colonies was in the hives without the heating system installed. The dependence of the brood area on time was monitored for the evaluation of both groups of the bee colonies. It was proven that the differential thermal regul ation enables the optimal growth of the bee colonies in the early spring period in accordance with the phenophases. The brood area increased evenly for the group of the bee colonies with a regulated temperature of the hive space, reaching a larger area

Raman spectroscopy meets extremophiles on Earth and Mars: studies for successful search of life

NoRecent studies relating to the analytical chemical characterization of terrestrial extremophiles reveal the presence of biomolecules that have been synthesized for the survival of the colonies in response to the extreme environmental conditions, where otherwise life could not exist. This is a vital part of the planned space missions now being undertaken to planets and their satellites in the search for extinct or extant life signatures in our Solar System. Extremophiles have existed on the Earth for some 3.8 Gyr and their interrogation indicates their strategic survival methods which can be associated and compared with extraterrestrial scenarios on Mars, Titan, Enceladus and Europa

The search for fullerenes in rocks from the Ries impact crater

Since their discovery, fullerenes have been reported from various geological environments. One group of these findings has been related to bolide impacts, e.g., the Sudbury crater and the K-T and P-T boundaries. Impact rocks of the Ries crater, Germany, including samples of suevites, metamorphosed crystalline clasts, and glass bombs, have been collected in the Otting, Altebürg, and Seelbronn quarries. No fullerenes in concentrations above 1 ppb have been found in analyzed samples. Laser desorption time-of-flight mass spectrometry (LD-TOF-MS) confirmed the absence of fullerenes in the analyzed samples. These results support the concept that the Ries impactor was a stony meteorite.The Meteoritics & Planetary Science archives are made available by the Meteoritical Society and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

An analytical Raman spectroscopic study of an important english oil painting of the 18th Century

NoAn opportunity was afforded to analyse pigment specimens from an unrestored oil painting in the style of the English School of the mid-18th Century prior to conservation being undertaken. Raman spectroscopy was adopted to characterise the pigments and indicated the presence of a novel red pigment which was assigned to the complex chromium mineral, hemihedrite, in addition to other interesting materials found in combination. This is the first recorded identification of hemihedrite spectral signals in an art context in a range of mineral pigments that are otherwise typical of this period and some hypotheses are presented to explain its presence based on its occurrence with associated mineral pigments. It is suggested that the presence of powdered glass identified in certain areas of the painting enhanced the reflectivity of the pigment matrix

Raman spectroscopic study of the Chromobacterium violaceum pigment violacein using multiwavelength excitation and DFT calculations

NoViolacein is a bisindole pigment occurring as a biosynthetic product of Chromobacterium violaceum and Janthinobacterium lividum. It has some structural similarities to the cyanobacterial UV-protective pigment scytonemin, which has been the subject of comprehensive spectroscopic and structural studies. A detailed experimental Raman spectroscopic study with visible and near-infrared excitation of violacein produced by C. violaceum has been undertaken and supported using theoretical DFT calculations. Raman spectra with 514 and 785 nm excitation of cultivated cells as well as extracts and Gaussian (B3LYP/6-311++G(d,p)) calculations with proposed molecular vibrational assignments are reported here