564 research outputs found
On the alleged phonetic value /p/ of the frog hieroglyph in Ptolemaic
The present article deals with two passages (Esna n° 379, 9 and Edfu III, 190, 2) which feature the frog hieroglyph with a supposed phonetic value /p/. While an alternative reading /H/ is suggested for the first text, the other requires returning to Nefertariâs tomb for disclosure of the frogâs meaning
Die Zahl 1095 als Chiffre fĂŒr den Weltgott â ein Ă€gyptischer Hintergrund fĂŒr Horapollo I,28?
«Isis, die ihren Sohn Horus schĂŒtzt». Eine Jerusalemer Statuette als Beispiel rundplastischer âčKryptographieâș?
Book Review: DâAuria, S.H. Ed. 2008. Servant of Mut: Studies in Honor of Richard A. Fazzini. â Leiden/Boston, Brill (Probleme der Ăgyptologie 28)
Schreibpalette und SchreiberidentitĂ€t â zu einer intentionalen Lacuna auf der Statue des Nachthorheb (Louvre A 94)
Nano spray drying of pharmaceuticals
[EN] Spray drying plays a crucial role in the processing of pharmaceutical products such as pills, capsules, and tablets as it is used to convert drug containing liquids into dried powdered forms. Nano spray drying is in particular used to improve drug formulation by encapsulating active ingredients in polymeric wall materials for protection and delivering the drugs to the right place and time in the body. The nano spray dryer developed in the recent years extends the spectrum of produced powder particles to the submicron- and nanoscale with very narrow size distributions and sample quantities in the milligram scale at high product yields. This enables the economical use of expensive active pharmaceutical ingredients and pure drugs. The present paper explains the concept of nano spray drying and discusses the influence of the main process parameters on the final powder properties like particle size, morphology, encapsulation efficiency, and drug loading. Application results of nano spray drying for the formulation and encapsulation of different drugs are reviewed.Arpagaus, C. (2018). Nano spray drying of pharmaceuticals. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat PolitĂšcnica de ValĂšncia. 611-618. https://doi.org/10.4995/IDS2018.2018.7356OCS61161
Experimental Comparison of HCFO and HFO R1224yd(Z), R1233zd(E), R1336mzz(Z), and HFC R245fa in a High Temperature Heat Pump up to 150 °C Supply Temperature
The use of industrial high-temperature heat pumps (HTHP) is particularly interesting for heat recovery applications and various industrial processes such as steam generation, drying, sterilization, paper production, or food preparation. The application of new synthetic hydrofluoroolefin (HFO) and hydrochlorofluoroolefin (HCFO) refrigerants with low environmental impact is becoming increasingly important in future HTHP. At our university in Switzerland, a laboratory-scale HTHP has been developed as part of the SCCER-EIP project (Swiss Competence Center for Energy Research â Efficiency of Industrial Processes). The developed heat pump is single-stage, operates with a variable speed piston compressor, and contains a continuously adjustable internal heat exchanger (IHX) for superheating control. A viscous POE oil (173 mm2/s at 40 °C) is used to achieve sufficient lubrication at high temperatures with the refrigerants. This paper presents the experimental performance of the HCFO and HFO refrigerants R1224yd(Z), R1233zd(E), and R1336mzz(Z) as drop-in replacements for the fluorinated hydrocarbon (HFC) R245fa in the same laboratory HTHP with 10 kW heating capacity. Starting from a reference point at W60/W110 (50 K temperature lift), a parameter study was performed to investigate the operating maps (i.e. heating capacity and COP) of the heat pump in the range from 30 to 80 °C heat source and 70 to 150 °C supply temperature. Besides, an overview of the thermophysical, environmental, and safety aspects of the refrigerants is given. At W60/W110 COPs of 3.2, 3.1, 3.0, and 3.1 for R1224yd(Z), R1233zd(E), R1336mzz(Z) and R245fa were measured. Up to about 110 °C, R1224yd(Z), R1233zd(E), and R245fa presented a slightly higher COP than R1336mzz(Z) due to higher heating capacities and lower relative heat losses at the same temperature conditions. Due to higher critical temperatures, R1336mzz(Z) was more efficient at 150 °C heat supply temperature. Otherwise, the differences in COP were within the measurement uncertainty of maximum ± 0.22 COP. The integration of the IHX in the heat pump cycle significantly increased the COP and the heating capacity over the entire operating map compared to a basic cycle. A further COP increase was achieved by a higher temperature glide on the heat supply side from 5 to 30 K (increased subcooling), which is promising in processes with low return temperatures. The drop-in tests also showed that the heating capacity of R1224yd(Z) was on average 9% higher than that of R1233zd(E), which in practice requires slightly smaller compressors to achieve a comparable heating capacity. Overall, the very low GWP, the non-flammability, and the negligible environmental impact (i.e. low trifluoroacetic acid (TFA) formation during atmospheric degradation) of the investigated HCFO and HFO refrigerants indicate a high potential for future use in HTHP applications and retrofit systems
Impact of Oxygen Stress and Energy Availability on Membrane Stability of Plant Cells
This article reviews the relationship between the energy status of plant cells under O2 stress (e.g. waterlogging) and the maintenance of membrane intactness, using information largely derived from suspension cultures of anoxiaâintolerant potato cells. Energyârelated parameters measured were fermentation endâproducts (ethanol, lactate, alanine), respiratory rate, ATP, adenylate energy charge, nitrate reductase activity and biomass. ATP synthesis rates were calculated from the first four parameters. Reactive oxygen species were estimated from H2O2 and superoxide levels, and the enzymatic detoxification potential from the activity levels of catalase and superoxide dismutase. Structureârelated parameters were total fatty acids, free fatty acids (FFAs), lipid hydroperoxides, total phospholipids, Nâacylphosphatidylethanolamine (NAPE) and cell viability. The following issues are addressed in this review: (1) what is the impact of anoxia on membrane lipids and how does this relate to energy status; (2) does O2 per se play a role in these changes; (3) under which conditions and to what extent does lipid peroxidation occur upon reâaeration; and (4) can the effects of reâaeration be distinguished from those of anoxia? The emerging picture is a reappraisal of the relative contributions of anoxia and reâaeration. Two successive phases (preâlytic and lytic) characterize potato cells under anoxia. They are connected by a threshold in ATP production rate, below which membrane lipids are hydrolysed to FFAs, and NAPE increases. Since lipid peroxidation occurs only when cells are reoxygenated during the lytic phase, its biological relevance in an already damaged system is questionabl
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