Aroma profiles of five basil (Ocimum basilicum L.) cultivars grown under conventional and organic conditions

A headspace solid-phase microextraction (HS-SPME) method coupled to gas chromatography–ion trap mass spectrometry (GC–ITMS) has been developed and applied for profiling of volatile compounds released from five Ocimum basilicum L. cultivars grown under both organic and conventional conditions. Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC–TOFMS) was employed for confirmation of identity of volatiles extracted from the basil headspace by SPME.     

Oxidation,ignition, and combustion of Al·I2 composite powders

Materials combining high energy density of metals with the biocidal activity of halogens are of interest for applications aiming to inactivate harmful aerosolized microorganisms by combined thermal and chemical effects. This effort develops nanocomposite Al-halogen materials to replace pure Al as a fuel additive in energetic formulations. Cryogenic milling of elemental aluminum and iodine is used to prepare powder-like composite materials for laboratory tests. In such materials, iodine is stabilized in aluminum matrix and is released when the materials are heated and ignited. Al·I₂ composite powders with the iodine concentration from 10 to 30 wt.% were prepared. Iodine release by and oxidation of such materials were investigated using thermo-gravimetric analysis. Ignition temperatures of the prepared powders were determined at the heating rates of 1000–22,000 K/s using an electrically heated filament. Composite powders ignite at lower temperatures compared to pure Al powders. Combustion characteristics of the prepared materials were investigated using a constant volume explosion test for aerosolized powders and laser ignition test for individual particles. In both combustion experiments pure Al served as a reference. Higher combustion rate and greater total pressure were observed for the aerosolized clouds of composite powders with 15 and 20 wt.% of iodine. For individual particles, the burn times were slightly longer and flame temperatures were slightly lower compared to those of pure aluminum. Both overall iodine concentration and its stability in the composite powders affected their ignition and combustion characteristics.     

Purification of brines by chemical precipitation and ion‐exchange processes for obtaining battery‐grade lithium compounds

Lithium salts are very important in the production of lithium batteries since they are used as precursors for the fabrication of cathode materials that require very low level of impurities (battery grade). Usually, the lithium extraction process from brine first yields lithium carbonate, which is then used as raw material for the production of other lithium compounds. However, it implies an increase in investment costs, considering more equipment and process stages. To remove the impurities and produce battery‐grade lithium compounds directly from brines, a laboratory‐scale process was developed using the methods of ion exchange and chemical precipitation. Thus, impurity‐free brine ready to be used in an industrial membrane electrolysis process is obtained. Different sequences and operating conditions were investigated for the purification of lithium‐concentrated brines, removing the main impurities of the natural brines: calcium, magnesium, and sulfate. For the characterization of solutions, crystals, and ion‐exchange resins, atomic absorption spectrophotometry, scanning electron microscopy, and X‐ray scattering spectroscopy were used. The results indicate that during the chemical precipitation process, lithium‐concentrated brine reacted with some additives (precipitating agents) at different stages in the batch reactors. Subsequently, the pulp obtained was sedimented and filtered, eliminating or reducing the impurities of the lithium brine. Thus, the most efficient precipitation sequence was evaluated as a function of the removal percentage of the species. The removal efficiencies obtained for Ca⁺², Mg⁺², and SO₄^?2 were of 98.93%, 99.93%, and 97.14%, respectively. Thereafter, the use of the ion‐exchange resins reduced the concentration of Ca⁺² and Mg⁺² to the values below 1 ppm. The combined use of both processes provided promising results that could be applied in the industry.     

Designing a personal informatics system for users without experience in self-tracking: a case study

Thanks to the advancements in ubiquitous and wearable technologies, Personal Informatics (PI) systems can now reach a larger audience of users. However, it is not still clear whether this kind of tool can fit the needs of their daily lives. Our research aims at identifying specific barriers that may prevent the widespread adoption of PI and finding solutions to overcome them. We requested users without competence in self-tracking to use different PI instruments during their daily practices, identifying five user requirements by which to design novel PI tools. On such requirements, we developed a new system that can stimulate the use of these technologies, by enhancing the perceived benefits of collecting personal data. Then, we explored how naïve and experienced users differently explore their personal data in our system through a user trial. Results showed that the system was successful at helping individuals manage and interpret their own data, validated the usefulness of the requirements found and inspired three further design opportunities that could orient the design of future PI systems.     

Production of stable amorphous form by means of spray drying

Spray drying is a very useful method for manufacturing of amorphous solid materials. This is mainly due to the possibility of fast solvent evaporation that leads to a rapid transformation of solution to a solid state. Besides evaporation kinetics, there are various process parameters that influence physical and chemical characteristics of such obtained material. The possibility of obtaining a stable amorphous structure of the active pharmaceutical ingredient in a spray dryer was examined. A solution of the hydrochloride crystalline structure of the active pharmaceutical ingredient in a mixture of water and acetonitrile was dried at different temperatures and flowrates of nitrogen used for atomization, as well as the flowrates of the solution. The influence of the process conditions on the properties of the product was analyzed. The final dried products were characterized and identified with a variety of analytical and physical methods. The results showed that a stable amorphous structure of the high purity active pharmaceutical ingredient is obtained, and that the optimal conditions of the process are defined. The amorphous structure is stable at temperatures below 200°C when it is transformed into a new crystal structure. Conditions of high relative air humidity lead to partial transformation.     

Determination of the percentage of wood failure by 3D scanning of the adhesive bondline

The quality of the wood-adhesive bond is usually determined by its shear strength and the percentage of wood failure, the latter usually being determined by visual evaluation and prone to the examiner’s subjective evaluation. A new technique of 3D scanning was used to evaluate the percentage of wood failure, and the results obtained were compared to those obtained by means of existing methods, i.e. the visual evaluation and image analysis techniques. Evaluation by 3D scanning showed comparable values for samples with a high percentage of wood failure, but large differences in the case of samples showing mainly adhesive failure.     

Carbosilane Metallodendrimers with Cyclopentadienyldichlorotitanium(IV) End Groups

Dendritic polyols of the second and third generation 2G-OH₈ (1), 2G-OH₁₆ (2), and 3G-OH₁₆ (3) were prepared by hydroboration/oxidation of allyl-terminated carbosilane dendrimers and used as supports for the immobilization of cyclopentadienyltrichlorotitanium(IV) complexes via alcoholysis. The reaction of 1–3 with CpTiCl₃ gave metallodendrimers 2G-(OTiCpCl₂)₈ (4a), 2G-(OTiCpCl₂)₁₆ (5a), and 3G-(OTiCpCl₂)₁₆ (6a), respectively, whereas the reaction of 1 and 3 with CpSi^FTiCl₃ (CpSi^F = C₅H₄SiMe₂CH₂CH₂C₈F₁₇) yielded peripherally fluorinated metallodendrimers 2G-(OTiCpSi^FCl₂)₈ (4b) and 3G-(OTiCpSi^FCl₂)₁₆ (6b). All metallodendrimers were characterized by multinuclear NMR spectroscopy. The suggested structures were supported by comparison with model 1-propoxycomplexes 10a,b. To identify side products of the alcoholysis reaction, hydrolytic behavior of the starting trichloro complexes was studied both in solid state and in solution. The main products of hydrolysis in solution were identified as μ-oxocomplexes 8a,b whereas hydrolysis in solid state yielded mainly hydroxycomplexes 7a,b.     

Cultivar differences of total anthocyanins and anthocyanidins in red and purple-fleshed potatoes and their relation to antioxidant activity

Total anthocyanins (TAC) and individual anthocyanidins (AN) after hydrolysis were measured in 15 red and purple-fleshed potato cultivars produced in five different locations in the Czech Republic and a new cultivar Blaue St. Galler from Switzerland. It was found that TAC, expressed as cyanidin content, varied between 0.7 mg 100 g⁻¹ FW (cv. Blue Congo) and 74.3 mg 100 g⁻¹ FW (cv. Blaue Ludiano). Major differences in cultivars were found for AN relative abundance. For cv. Highland Burgundy Red a high proportion of pelargonidin (98.7%) was characteristic, whereas cv. British Columbia Blue contained almost exclusively cyanidin. Cultivars Violette and Vitelotte showed a relatively high content of malvidin. Cultivar Shetland Black differed from others with its higher content of peonidin (on average 36.7%). High petunidin abundance in the cultivars Valfi, Blue Congo, Salad Blue, Blaue St. Galler, Blaue Hindel Bank, Blaue Ludiano, Blaue Schweden, Farbe Kartoffel and Salad Red was found. TAC and AN contents highly corresponded with antioxidant activity (AA) determined with the ABTS, FRAP and DPPH assays in vitro. High AA was shown by the cultivars Vitelotte, Violette, Blaue Ludiano, Hafija, and Highland Burgundy Red. Increased height above sea level, higher annual sum of precipitation, and lower annual average temperatures caused higher AA and TAC. A high degree of hydroxylation and/or methoxylation of individual anthocyanidins could contribute in conjunction with other phenolics to high AA (peonidin, delphinidin and malvidin in the cultivars Blue Congo, Highland Burgundy Red and Shetland Black). Consequently, new red and purple-fleshed cultivars with high TAC and highly methoxylated and/or hydroxylated AN could be a promising source of favourable antioxidants in human nutrition.     

An attempt to predict pork drip loss from pH and colour measurements or near infrared spectra using artificial neural networks

The ability to predict meat drip loss by using either near infrared spectra (SPECTRA) or different meat quality (MQ) measurements, such as pH₂₄, Minolta L^∗, a^∗, b^∗, along with different chemometric approach, was investigated. Back propagation (BP) and counter propagation (CP) artificial neural networks (ANN) were used and compared to PLS (partial least squares) regression. Prediction models were created either by using MQ measurements or by using NIR spectral data as independent predictive variables. The analysis consisted of 312 samples of longissimus dorsi muscle. Data were split into training and test set using 2D Kohonen map. The error of drip loss prediction was similar for ANN (2.2–2.6%) and PLS models (2.2–2.5%) and it was higher for SPECTRA (2.5–2.6%) than for MQ (2.2–2.3%) based models. Nevertheless, the SPECTRA based models gave reasonable prediction errors and due to their simplicity of data acquisition represent an acceptable alternative to classical meat quality based models.