Search results for "chemical propertie"
showing 10 items of 59 documents
Gamma irradiation of graphene quantum dots with ethylenediamine: Antioxidant for ion sensing
2020
Due to the low consumption of chemicals, the absence of toxic residual side products, the procedure simplicity and time-saving aspects, gamma irradiation offers advantages over the classical chemical protocols. We successfully employed gamma irradiation in order to introduce N-atoms in Graphene Quantum Dots (GQDs). By irradiating GQDs water dispersions in the presence of isopropyl alcohol and ethylenediamine, at doses of 25, 50 and 200 kGy, we attached amino groups onto GQDs in a single synthetic step. At the same time, a chemical reduction is achieved, too. Selected conditions induced incorporation of N-atoms within GDQs atomic lattice (around 3 at%), at all applied doses. Additionally, th…
Comparative study on the quality characteristics of some Egyptian mango cultivars used for food processing
2016
This study aims to investigate the physical, chemical, rheological and sensorial properties of six common mango (Mangifera indica) cultivars in Egypt. These common cultivars were Alfonse, Sedeka, Awis, Sinara, Sukari and Zibdia. Weights of mango fruits ranged between 246.6 and 549.2 g. The highest significant value of sphericity was in Alfonse fruits (0.82), whereas the lowest value was 0.58 in Sinara fruits. The highest firmness value was 29.51 N in Sedeka fruits. The highest elasticity was 1.16 N/mm for Sukari fruits. The significantly color intensity chroma was recorded by Sinara, whereas the highest total color index (ΔE) was 88.41 for Sedeka mango cultivar. The significantly lowest pH …
Physico-chemical Properties of Anodic Oxide Films: from Passivity to Electronics
2014
Effect of grape pomace from red cultivar 'Nero d’Avola' on the microbiological, physicochemical, phenolic profile and sensory aspects of ovine Vasted…
2022
Abstract Aims The purpose of this study was to functionalize an ovine stretched cheese belonging to 'Vastedda' typology with red grape pomace powder (GPP) of Nero d’Avola cultivar and to characterize the microbiological, physicochemical, phenolic profile and sensory characteristics of the final cheeses. Methods and Results Before cheeses production, GPP was characterized for its microbiological profile, antibacterial activity and polyphenolic content. No colonies of bacteria and yeasts were detected in the GPP. GPP showed a large inhibition spectrum against spoilage and pathogenic bacteria. Three classes of polyphenolic compounds belonging to flavan-3-ols, flavonol and phenolic acids were i…
Evolution of indigenous starter microorganisms and physicochemical parameters in spontaneously fermented beef, horse, wild boar and pork salamis prod…
2020
Abstract The present work was carried out to evaluate the microbiological and physicochemical composition of salamis produced with the meat of beef, horse, wild boar and pork. Salami productions occurred under controlled laboratory conditions to exclude butchery environmental contaminations, without the addition of nitrate and nitrite. All trials were monitored during the ripening (13 °C and 90% relative humidity) extended until 45 d. The evolution of physicochemical parameters showed that beef and pork salamis were characterized by a higher content of branched chain fatty acids (FA) and rumenic acid than horse and wild boar salamis, whereas the last two productions showed higher values of …
Influence of Citrus Essential Oils on the Microbiological, Physicochemical and Antioxidant Properties of Primosale Cheese
2022
The aim of this study was to produce a fresh ovine pressed cheese within Pecorino “Primosale” typology with the addition of citrus essential oils (EOs). For this purpose, ewe’s pasteurized milk was added with EOs from the peel of lemons, oranges and tangerines. Seven cheese productions were performed at the pilot plant scale level, including one control production (CP) without the addition of EOs and six experimental productions obtained by the addition of two EO concentrations (100 and 200 µL/L) to milk. The acidification process was obtained by means of the starter cultures Lactococcus lactis CAG4 and PON36. All cheeses showed levels of lactic acid bacteria (LAB) a…
Gluconic acid for eco-friendly Ionic Liquids: chemical and biological investigations
Ionic liquids (ILs) are employed in several fields thanks to their well-known properties. For a long time, ILs were considered the “green” alternative to conventional organic solvents.1 However, the increasing attention on environmental health led to consider different ILs structures and alternative synthetic pathways. Considering the tunability of IL structures, new synthetic approaches with natural sources as starting materials were taken into account.2 Here, new eco-friendly ILs were synthesised using gluconic acid. The structures carry gluconic moiety on the cation or as the anion (Figure 1). Hence, several OH groups decrease toxicity and shape a high coordinative site. These new organi…
Soil quality indicators as affected by a long term barley-maize and maize cropping systems
2011
Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L.) and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L.) with Italian ryegrass (R3) and grain-maize maintained in these conditions for 18 years. Each crop system was submitted to two management options: 1) the high input level (H), done as a conventional tillage, 2) the low input level (L), where the tillage was replaced by harrowing and the…
Steviol glycosides and bioactive compounds of a beverage with exotic fruits and Stevia rebaudiana Bert. as affected by thermal treatment
2020
The aim of this study was to investigate the effects of thermal processing on physicochemical properties, steviol glycosides, bioactive compounds, and antioxidant capacity degradation of a beverage based on exotic fruit juices, orange juice, açaí, and oat and sweetened with Stevia rebaudiana water extracts at different concentrations. The experimental design comprised a response surface methodology according to a central composite face-centered design. The variable ranges were 60–99°C, 0.25–15 min, 0–2.5% Stevia percentage. This design was used to determine the optimal thermal processing-Stevia concentration in order to obtain the best retention of bioactive compounds and physicochemical pr…
Properties of titanium dioxide
2021
"Properties of titanium dioxide" presents a survey of the main physicochemical properties of TiO2 upon which rely all of the applications of this material. Structures and morphologies of titanium dioxide have been taken into account, also in correlation with thermodynamic properties. Bulk and surface defectivity has been described in detail, because of its relevant consequences in terms of catalytic activity. The basic mechanisms of interaction between photons and TiO2 have been discussed on the basis of the optoelectronic features of the semiconductor. Finally, electrical, mechanical, and rheological properties of TiO2 have been presented.