Determination of the eutectic solubility lines of the ternary system NaHCO3–Na2CO3–H2O

A crystallizer was built and a procedure developed to accurately measure the eutectic solubility lines where ice and salt coexist in equilibrium with the solution, for potential application of Eutectic Freeze Crystallization. The eutectic solubility lines of the ternary system NaHCO₃–Na₂CO₃–H₂O were determined experimentally and calculated with the extended UNIQUAC model. The extended UNIQUAC model describes the experimental data quite well. Anhydrous NaHCO₃ and Na₂CO₃·10H₂O were the only two types of crystals present in equilibrium with ice crystals in the ternary system. At the quadruple point NaHCO₃ and Na₂CO₃·10H₂O are in equilibrium with a solution of about 4.34 wt% of Na₂CO₃ and 4.77 wt% of NaHCO₃ at −3.32 °C. The anhydrous NaHCO₃ crystals were needle shaped with lengths between 5 and 10 μm, that were agglomerated into particles of about 100–300 μm, while the Na₂CO₃·10H₂O crystals were hexagonally shaped with sizes between 100 and 500 μm.     

Characterization of interphase adhesion in multi-layer coating systems

Multi-layer coating systems are the state of the art for painting of metal and plastic surfaces e.g. in the automotive industry. Utilizing such systems consisting of several specialized coating materials, a high adhesion and a good corrosion protection can be reached, along with good barrier properties, chemical and scratch resistance as well as appealing surface appearance. The interphase regions between single layers of such systems represent areas of a potential weakness, where a delamination and a premature coating degradation can start. To test in a short time the protective properties of the coating, a special hydrothermal cyclic loading test procedure was developed, which causes accelerated build-up of internal stress within the coating system. Using an electrochemical impedance spectroscopy with various optimized electrode geometries, it was possible to detect the early stages of coating degradation and to compare different coating systems. Internal stress measurements contributed additionally to a better understanding of the coating degradation.     

0.8 μW 12-bit SAR ADC sensors interface for RFID applications

The design and first measuring results of an ultra-low power 12 bit successive-approximation ADC for autonomous multi-sensor systems are presented. The comparator and the DAC are optmised for low power consumption. The power consumption is 0.52 μW from a 1.2 V supply with a sample clock of 3.125 kHz and 0.85 μW at 6.25 kHz. This gives 136 pJ per conversion or 66 fJ per conversion step. As per authors’ knowledge, 66 fJ per conversion step is the best reported so far.The ADC was realised in the NXP CMOS 0.14 μm technology; the area was 0.35 mm². Only four metal layers were used in order to allow 3D integration of the sensors.     

Inactivation of <Emphasis Type="Italic">Salmonella enterica</Emphasis> in a Rice Beverage by Ultrasound: Study of the Parameters Affecting the Antibacterial Effect

The topic of this paper is the investigation of the antibacterial effect of ultrasound (US) towards Salmonella enterica in a rice beverage. The beverage was inoculated at different levels (8 and 5 log CFU/mL) and US-treated; then, a challenge test under refrigeration was carried out. The maximum net power of the equipment was 130 W; the treatment was carried out at 40–100% of the net power, for 2–10 min; the pulse was set to 2–10 s. For both the inoculum levels, power and time were the most important factors for the antimicrobial effect towards S. enterica. The combinations resulting in the highest inactivation of the pathogen were tested during the challenge test at 4 °C, and in some combinations, S. enterica remained below the detection limit for 13 days.     

Crosslinking and grafting ethylene vinyl acetate copolymer with accelerated electrons in the presence of polyfunctional monomers

In this study, we have studied the effects of polyfunctional monomers (PFMs) on physical properties of ethylene vinyl acetate (EVA) copolymer crosslinked with electron beam (EB) or peroxides. The PFMs used were triallylcyanurate, triallylisocyanurate, trimethylolpropane trimethacrylate, zinc diacrylate, and ethylene glycol dimethacrylate. Using PFMs has led to (1) optimum cure time t ₉₀ decrease from 19′25″ to 17′30″–18′45″, (2) scorch time increase from 2′ to maximum 3′45″, (3) increasing the crosslink density of peroxide or EB-cured systems by increasing the efficiency of productive radical reactions. The most efficient PFM for EVA copolymer blends has been triallylisocyanurate. Tensile strength and tear strength of samples crosslinked with EB for all irradiation doses are significantly better than those obtained for samples crosslinked with peroxides (differences up to 190%). The results show that EB irradiation gave the best results     

Chemical modification of chloromethylated polysulfones via click reactions

A new approach to the modification of azidomethyl polyethersulfones using click reactions with acetylenic derivatives in the presence of CuBr as catalyst is presented. An azidomethyl polyethersulfone was prepared by the reaction of chloromethylated polysulfone with sodium azide in dimethylformamide. By the Cu(I)‐catalysed Huisgen 1,3‐dipolar cycloaddition reaction of the azidomethyl polyethersulfone to acetylenic derivatives, new polyethersulfones containing 1,2,3‐triazole rings were obtained. The structures of the polymers were confirmed using attenuated total reflectance Fourier transform infrared and NMR spectroscopy. The polymers were characterized using dynamic mechanical analysis, thermogravimetric analysis, stress‐strain and water contact angle measurements and solubility tests. The polymers bearing 1,2,3‐triazole rings having OH or COOH as substituents exhibited static contact angles smaller than that of the parent polyethersulfone. Copyright © 2010 Society of Chemical Industry     

Identification of Host Attractants for the Ethiopian Fruit Fly, <Emphasis Type="Italic">Dacus ciliatus</Emphasis> Loew

The Ethiopian fruit fly, Dacus ciliatus, is an oligophagous pest of cucurbit crops, particularly melons, cucumbers, and marrows (summer squash). The present study aimed to identify host attractants for D. ciliatus and was guided by a behavioral bioassay and an electrophysiological assay. We tested volatile compounds from the fruits of a host plant, ripe and unripe Galia melon, Cucumis melo var. reticulates. Both sexes were attracted to melon volatiles. Those of ripe melon were preferred. Gas chromatography-electroantennographic detection analysis of the behaviorally active ripe melon volatiles consistently showed that 14 compounds elicited similar antennal responses from both sexes. Twelve compounds were identified by gas chromatography-mass spectrometry (GC-MS) using GC-MS libraries, retention indices (RI), and authentic standards. The electrophysiological activities of the compounds that were present at sufficient levels for identification, benzyl acetate, hexanyl acetate, (Z)-3-hexenyl acetate, (Z)-3-octenyl acetate, octanyl acetate, (Z)-3-decenyl acetate, and (E)-β-farnesene, were evaluated at six different dosage levels by using electroantennography (EAG). Benzyl and hexanyl acetates elicited dose responses only in males, while other tested compounds elicited dose responses in both sexes. The strongest responses were observed for doses between 100 ng and 10 μg. The dose response, in terms of attractiveness to synthetic compounds within the active range (as determined by EAG), also was evaluated in the behavioral bioassay. Synthetic acetates were attractive to both sexes when tested individually. Significant attraction was observed when individual compounds were applied in the bioassay arena at doses of 0.5–1 μg/dispenser. Blends of compounds in equal proportions also were attractive to the insects. The most attractive blend was a mixture of four or five identified acetates. The addition of an equal proportion of (E)-β-farnesene to this mixture had a deterrent effect.