FORTH and microprocessor applications at the Royal Greenwich Observatory

In common with other activities that make extensive use of electronics and computing, astronomy has been profoundly affected by the availability of minicomputers and microprocessors. These devices have brought with them a revolution both in the quality of astronomical data and in the ease with which that data may be obtained; many exciting astronomical research results have been obtained as a direct consequence. This paper describes the microprocessor program at RGO, including the hardware, why it was chosen and how it is possible to cope with rapid technological changes, and the software which unifies the different processors. It describes highlights of the projects for which microprocessors have been used so far, and discusses some likely future developments in astronomical applications.     

Experimental investigation on injection characteristics of bioethanol-diesel fuel and bioethanol-biodiesel blends

This paper analyses the fuel injection characteristics of bioethanol-diesel fuel and bioethanol-biodiesel blends considered as fuel for diesel engines. Attention is focused on the injection characteristics which significantly influence the engine characteristics and subsequently the exhaust emissions. In this context the following injection characteristics have been investigated experimentally: fuelling, injection timing, injection delay, injection duration, mean injection rate, and injection pressure. The tested fuels were neat mineral diesel fuel, neat biodiesel made from rapeseed oil, bioethanol/diesel fuel and bioethanol/biodiesel blends up to 15% (v/v) bioethanol with an increment of 5%. The fuels blends were experimentally investigated in a fuel injection M system at rated condition (FL, 1100 rpm), peak torque (FL, 850 rpm), and maximum pump speed (1100 rpm) for different partial loads (PL 75% and PL 50%), at ambient temperature.It has been proven that for all operating regimens tested, the addition of bioethanol to biodiesel reduces fuelling, injection timing, injection duration, mean injection rate and maximum injection pressure and increases injection delay compared to pure biodiesel. Meanwhile, increasing bioethanol in diesel fuel shows no significant variations or a slightly increase in fuelling, injection timing, injection duration, and mean injection rate and a decrease in injection delay and maximum injection pressure, compared to pure diesel fuel.The influence of bioethanol in biodiesel is much more significant that in diesel fuel; it has a beneficial effect on biodiesel injection characteristics because bioethanol addition brings them nearer to the diesel fuel one and it is expected to decrease biodiesel NO_x emissions.     

From Coin to Medal: A Metallurgical Study of the Brazing Drop on a 19th Century Scudo

In the past, it was customary to use out-of-circulation coins as pendants by brazing a peg or ring on the edge of the coin in order to transform it into a devotional or decorative object; this practice was very common for specimens of the Papal States, especially for silver coins. This metallurgical investigation of a 19th century Scudo aimed to relate the internal structure of the coin to the minting technology with a special focus on the brazing drop, in order to provide information on the solidification microstructure arising from a strongly nonequilibrium process such as brazing. The results show that the Ag content in the coin ranges from 92% in the bulk up to 97% on the surface, due to enrichment, while analysis of the brazing revealed that it consists of an Ag-Cu-Zn-Pb alloy, for which the melting temperature has been estimated. Considering the distribution of minor elements, Zn segregates in the secondary (Cu-rich) ??-dendrites and inside the whole eutectic structure, while Pb is only present in the Ag-based phases and seems to reduce the solubility of Zn inside the primary (Ag-rich) ??-dendrites.     

Influence of stacking fault energy in electrically assisted uniaxial tension of FCC metals

Electrically assisted manufacturing is based on the electro-plastic effect induced by electricity on the material flow during deformation and represents an alternative method for forming materials. Several studies have pointed out the real effectiveness of this technique, but no relations among microstructure, electrical resistivity, crystal structure and deformation-mode have been revealed. In the present work, the stacking fault energy (SFE) was taken into account and three FCC materials possessing different SFEs were strained in electrically assisted uniaxial tension under continuous current application. The results showed an advantageous electric contribution only in the highest SFE material, whereas no enhancements in formability were revealed in the investigated low- and intermediate-SFE metals.     

Carbothermal Reduction of Iron Ore Applying Microwave Energy

This paper presents the results of a study on carbothermal reduction of iron ore made under the microwave field in equipment specially developed for this purpose. The equipment allows the control of radiated and reflected microwave power, and therefore measures the microwave energy actually applied to the load in the reduction process. It also allows performing energy balances and determining the reaction rate with high levels of confidence by simultaneously measuring temperature and mass of the material upon reduction with high reproducibility. We used a microwave generator of 2.45 GHz with variable power up to 3000 W. Self‐reducing pellets under argon atmosphere, containing iron ore and petroleum coke, with 3.5 g of mass and 15 mm of diameter were declined. We obtained the kinetic curves of reduction of iron ore and of energy consumption to the process in the maximum electric field, in the maximum magnetic field and at different values of power/mass. The data allow analyzing how the microwave energy was actually consumed in the reduction of ore.     

Synthesis and in vitro and in vivo Antifungal Activity of the Hydroxy Metabolites of Saperconazole

Herein we describe the scalable diastereoselective and enantioselective syntheses of eight enantiomers of hydroxy metabolites of saperconazole. The in vitro antifungal activity of the eight stereoisomers (compounds 1 – 8 ) was compared against a broad panel of Candida spp. (n=93), Aspergillus spp. (n=10), Cryptococcus spp. (n=19), and dermatophytes (n=27). The four 2S isomers 1 – 4 of the new agent were generally slightly more active than the four 2R isomers 5 – 8 . All eight isomers were tested in a model of experimental A. fumigatus infection in guinea pigs by intravenous inoculation of the fungal conidia. Treatment doses were 1.25 mg kg^?1 and 2.5 mg kg^?1 per day. Infection severity was measured in terms of mean survival time (MST) after infection and mean tissue burdens in brain, liver, spleen, and kidney at postmortem examination. Among the eight isomers, the 2S diastereomers 1 – 4 showed a generally higher level of activity than the 2R diastereomers 5 – 8 , revealing compounds 1 and 4 as the most potent overall in eradicating tissue burden and MST. Compared with reference compounds itraconazole and saperconazole, the hydroxy isomers 1 – 8 are less potent inhibitors of the growth of A. fumigatus in vitro and of ergosterol biosynthesis in both A. fumigatus and C. albicans.     

Possible Adverse Effects of Food Additive E171 (Titanium Dioxide) Related to Particle Specific Human Toxicity,Including the Immune System

Titanium dioxide (TiO₂) is used as a food additive (E171) and can be found in sauces, icings, and chewing gums, as well as in personal care products such as toothpaste and pharmaceutical tablets. Along with the ubiquitous presence of TiO₂ and recent insights into its potentially hazardous properties, there are concerns about its application in commercially available products. Especially the nano-sized particle fraction (<100 nm) of TiO₂ warrants a more detailed evaluation of potential adverse health effects after ingestion. A workshop organized by the Dutch Office for Risk Assessment and Research (BuRO) identified uncertainties and knowledge gaps regarding the gastrointestinal absorption of TiO₂, its distribution, the potential for accumulation, and induction of adverse health effects such as inflammation, DNA damage, and tumor promotion. This review aims to identify and evaluate recent toxicological studies on food-grade TiO₂ and nano-sized TiO₂ in ex-vivo, in-vitro, and in-vivo experiments along the gastrointestinal route, and to postulate an Adverse Outcome Pathway (AOP) following ingestion. Additionally, this review summarizes recommendations and outcomes of the expert meeting held by the BuRO in 2018, in order to contribute to the hazard identification and risk assessment process of ingested TiO₂.     

Effect of the Heat Treatment on the Corrosion Resistance of Duplex Stainless Steels

Duplex stainless steels (DSS) are biphasic austenitic-ferritic steels in which the best combination of mechanical and corrosion resistance properties is achieved for an almost equal volume fraction of the phases. In this work, the effect of secondary phases precipitation on the corrosion resistance of four DSS grades (2101, 2304, 2205 and 2507), after isothermal aging in the critical temperature range 750-900 °C, was studied. The corrosion resistance was investigated by potentiodynamic polarization tests in both 0.6 M NaCl solution (pH 7) and in an acid chlorinated solution (pH 3) at room temperature. Moreover, the critical pitting temperature was determined according to ASTM G150. The results showed that secondary phases precipitation mainly influenced the resistance to corrosion of the lean duplex grades.     

Influence of biodiesel on engine combustion and emission characteristics

This paper discusses the influence of biodiesel on the engine combustion characteristics. The considered fuel is neat biodiesel from rapeseed oil. The considered engine is a bus diesel engine with injection M system. The engine characteristics are obtained by experiments and numerical simulation. The results obtained with biodiesel are compared to those obtained with mineral diesel under various operating regimes. In this way, the influences of biodiesel usage on the injection pressure, injection timing, ignition delay, in-cylinder gas pressure and temperature, heat release rate, exhaust gas temperatures, harmful emissions, specific fuel consumption, and on engine power are analyzed. Furthermore, the relationships among fuel properties, injection and combustion characteristics, harmful emissions, and other engine performance are determined. Special attention is given to possible explanations of higher NO_x emission in spite of lower in-cylinder gas temperature.