UML-based performance engineering possibilities and techniques

An information system's performance in relation to time and resources is largely determined by the design selected in software development. Performance engineering's core concept accounts for a software system's performance from the earliest development phases. Unfortunately, these measures are not performed explicitly during software development, primarily because of deadline pressure, the information system's complexity, or lack of knowledge of what PE means. The authors overview UML-based PE, analyze corresponding approaches, and examine the advantages of the tools available     

Differentialthermoanalytische Untersuchungen zur effektivität einiger Stabilisatoren bei Polyäthylenterephthalat

The thermooxidative resistance of poly(ethylene terephthalate), synthesized in the presence of different stabilizers as well as combinations of stabilizers as well as combinations of stabilizers, is studied with the help of the dynamic and isothermal DTA-method. The stabilization coefficients (by the dynamic DTA) and the characteristic induction periods (by the isothermal DTA) are determined. A good correlation is established between the data obtained by both methods.     

Stereospecific analysis of triglycerides from apple seed endosperm

Triglyceride composition and stereospecific distribution of fatty acids in apple seed oil are reported. Results are compared with proposed distribution theories.     

Die mechanisch-chemische degradation von polymeren bei der verarbeitungstemperatur

There is a number of questions that remains unanswered by the literature regarding mechano-chemical degradation of plastics at the temperatures of processing. The investigations described here were carried out to determine the degree to which different polymers are degraded at the temperatures of processing under the influence of mechanical forces and to determine the relationship between melt viscosity and degree of degradation, as well as to understand the mechanism and the kinetics of degradation.     

Patulin in fruit juices: occurrence,bioaccessibility, and risk assessment for Serbian population

This paper reports the first study of patulin occurrence in fruit juices and risk assessment related to patulin intake by children, adolescents and adults in Serbia. During 3 consecutive years (2013–2015), 142 fruit (apple or multi-fruit) juices were collected from the market and analysed using HPLC-UV. Patulin was found in 51.4% of juices with 0.7% of the samples in excess of the legal limit of 50 μg kg^?1 (mean 4.3 μg kg^?1). Apple juices showed significantly higher percentage of contaminated samples (74.0% vs 27.5%), as well as higher mean patulin content (6.4 vs 2.1 μg kg^?1) when compared with the multi-fruit ones. Bioaccessibility of patulin in fruit juices was studied using the standardised in vitro digestion method. A mean of 21.6% of the initial patulin amount reached the end of the intestinal phase showing a significant reduction of this toxin during the human digestion process. Risk assessment of patulin intake by Serbian children, adolescents and adults, conducted by deterministic and probabilistic approaches and including the bioaccessibility results, revealed no health concern. Although patulin alone does not represent risk, further research should consider its co-occurrence with other toxic substances in food and potential adverse effects of their mixtures.     

Variations of Infiltration and Electronic Contact in Mesoscopic Perovskite Solar Cells Revealed by High‐Resolution Multi‐Mapping Techniques

A combination of high‐resolution mapping techniques is developed to probe the homogeneity and defects of mesoscopic perovskite solar cells. Three types of cells using a one‐step infiltration process with methylammonium lead iodide (MAPbI₃) or 5‐ammoniumvaleric acid‐MAPbI₃ solutions, or two‐step process with MAPbI₃ solution are investigated. The correlation between photoluminescence, photocurrent, electroluminescence, and Raman maps gives a detailed understanding of the different infiltration mechanisms, electronic contact at interfaces, and effect on local photocurrent for the cells. The one‐step MAPbI₃ cell has very limited infiltration of the perovskite solution which results in poor device performance. High loading of the mesopores of the TiO₂ and ZrO₂ scaffold is observed when using 5‐ammoniumvaleric acid, but some micrometer‐sized non‐infiltrated areas remain due to dense carbon flakes hindering perovskite infiltration. The two‐step cell has a complex morphology with features having either beneficial or detrimental effects on the local photocurrent. The results not only provide key insights to achieving better infiltration and homogeneity of the perovskite film in mesoporous devices but can also aid further work on planar devices to develop efficient extraction layers. Moreover, this multi‐mapping approach allows the correlation of the local photophysical properties of full perovskite devices, which would be challenging to obtain by other techniques.