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关键词： Semi-dried buckwheat noodle   Aqueous ozone mixing   Quality   Microbial stability  

摘要： The microbiological, microstructural, and physicochemical impact of aqueous ozone mixing (AOM) on semidried buckwheat noodles (SBWN) was elucidated in this study. Microbiological measurements declared that AOM reduced the initial total plate count (TPC) of SBWN significantly (P < 0.05) with a prolonged shelf-life of 2 similar to 5 days. Meanwhile, AOM reduced the cooking loss and water absorption along with the enhancement of hardness and tension force. Scanning electron microscopy (SEM) showed that the protein network of surface and cross section became continuous and compact, and wrapped starch granules more effectively. Moreover, an obvious increase in the intensity of the high molecular protein bands was observed in the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) patterns. Furthermore, the sodium dodecyl sulfate extractable protein (SDSEP) under non-reducing condition obviously decreased, and then the SDSEP under reducing condition changed insignificantly (P > 0.05). These results indicated that AOM mainly promoted the protein cross-linking of SBWN by disulfide bond (SS) cross-links.

关键词： Pulse electrodeposition   Doping   Indium antimonide   Tellurium  

摘要： The main objective of our study was to develop an electrochemical synthesis method for obtaining Te-doped InSb thin films. The electrodeposition was performed using a pulse mode in a citrate bath containing 0.06 M InCl3, 0.045 M SbCl3 and 0-0.008 M TeO2. Firstly, the optimization of following parameters was carried out: the potential of pulse "off' (E-off), duration of pulse "off' (t(off)), and the ratio of time "on" to time "off" (t(on)/t(off)). We have confirmed that appropriate selection of electrodeposition conditions allows obtaining a material with a controllable morphology and chemical composition. Based on performed studies, optimal parameters for electrodeposition of thin Te-doped InSb films were selected. In the next stage, the pulse electrodeposition of Tedoped InSb films at previously optimized conditions was conducted from a solution containing different concentrations of the TeO2 precursor. It was demonstrated that adjustment of the TeO2 content in the citrate bath allows controlling the dopant concentration in thin Te-doped InSb films. Such a controllable synthesis creates the opportunity for tuning physicochemical properties of the material. The effect of doping on the crystal structure, phase composition, surface roughness, and optical band gap of thin Te-doped InSb films was discussed in detail.

关键词： Coconut cake dietary fibre   Carboxymethylation   Hydroxypropylation   Dual enzyme hydrolysis combined with heating   Functional properties   Antioxidant  

摘要： The effects of carboxymethylation, hydroxypropylation and dual enzyme hydrolysis combined with heating on some physicochemical and functional properties, and antioxidant activity of coconut cake dietary fibre (CCDF) were studied. Results showed that both the hydroxypropylation and carboxymethylation could effectively improve (p < 0.05) the water retention capacity (WRC), oil retention capacity (ORC), viscosity, alpha-amylase inhibition activity (alpha-AAIR), glucose dialysis retardation index (GDRI), cation-exchange capacity, emulsifying capacity index (ECI) and bile adsorption capacity (BAC) of CCDF. Moreover, the cellulase and hemicellulase hydrolysis combination with heating significantly enhanced (p < 0.05) the soluble dietary fibre content, WRC, emulsion stability, GDRI, alpha-AAIR and BAC of CCDF;but caused decrease in ORC and browning of color. In addition, improvement of total phenol content, Fe2+ chelating ability, ABTS(+)center dot and O-2(-)center dot scavenging activity were obtained in carboxymethylaticted CCDF. These effects were mainly attributed to the composition and structural modifications as evident from SEM, FT-IR and XRD analysis.

关键词： Hydrogen  

摘要： Friction is a ubiquitous manifestation of nature, and when it is studied at the nanoscale, complex and interesting effects arise from fundamental physical and chemical surface properties. Surprisingly, and probably due to the complexity of nanofriction studies, this aspect has not been completely discussed in prior studies. To fully consider the physicochemical influence in nanoscale friction, amorphous carbon films with different amounts of hydrogen and fluorine were prepared, chemically characterized, and evaluated via lateral force microscopy. Hydrogen and fluorine were selected because although they exhibit different physicochemical properties, both contribute to frictional force reduction. Indeed, to explain the experimental behavior, it is necessary to propose a new damping constant unifying both polarizability (physical) and electronegativity (chemical) properties. The satisfactory agreement between theory and experiments may encourage and enhance deeper discussion and new experiments that take into account the chemical peculiarities of frictional behavior relating to nanoscale elastic regimes.

关键词： Guar gum   Celiac disease   Tarhana   Corn flour   Hydrocolloid   Locust bean gum   Xanthan gum  

摘要： Purpose Celiac disease patients cannot consume gluten-containing diets;thus, gluten-free products should be offered to meet the nutritional needs of these patients. The purpose of this study was to produce gluten-free tarhana for celiac disease patients using corn flour instead of wheat flour and investigate some physicochemical properties of tarhana. Hydrocolloids were used to compensate for technological deficiencies caused by the absence of gluten. Design/methodology/approach Hydrocolloids including guar gum, xanthan gum and locust bean gum were added at concentrations of 0.5% and 1.0% to the corn flour. The substituted corn flour samples were used to produce tarhana powder. Findings The pH and acidity measurements were carried out in 0th, 24th and 48th h of fermentation, and for all samples, the pH gradually decreased during fermentation, whereas the acidity increased. According to the color measurements (L, a and b values), it was observed that there was no significant difference (p = 0.588) between the gums in terms of L values in tarhana dough samples. Water retention capacity values of control, guar gum 1%, xanthan gum 1% and locust bean gum 1% were found to be 1.1, 1.1, 0.7 and 1.2 mL/g, respectively. The viscosity measurements were carried out at three different temperatures (30 degrees C, 45 degrees C and 60 degrees C), and the viscosity values were found to decrease significantly (p = 0.000) with the increase in temperature for all the samples studied. The highest viscosity values were obtained by 1.0% xanthan gum (4,333 mPa s) and 0.5% locust bean gum (3,575 mPa s) added tarhana samples for 3 rpm at 30 degrees C. Xanthan gum addition showed the lowest foam capacity values (0.04 mL/mL) among the samples. The samples with guar gum, xanthan gum and locust bean gum are recommended with regard to consistency and foam stability in the production of tarhana. Originality/value This study confirms that the use of gums in tarhana, a gluten-free system, is benefic

摘要： Purpose. To evaluate the influence of ultrasonic activation on the physicochemical properties of setting time (ST), flow (FL), dimensional change (DC), and solubility (SL) of the cements: MTA, MTA Repair HP, and Biodentine (R). Materials and Methods. Two experimental groups were formed according to the cement activation protocol: without ultrasonic activation and with ultrasonic activation. Cements were manipulated according to the manufacturers' instructions. Ultrasonic activation group was performed with an E1 insert at power 3 (24-32 kHz) for 30 s directly in the center of the cement mass. The molds for analysis of the physicochemical properties were filled out and evaluated according to specification No. 57 from ANSI/ADA. The results were analyzed using the ANOVA test (two-way), complemented by Tukey's test (alpha = 0.05). The distilled water used during the solubility test was submitted to spectrometry to verify the release of calcium ions. The morphologies of the external surface and the cross-section of the samples were analyzed by means of a scanning electron microscope (SEM). Results. For the ST, ultrasonic activation reduced the values of MTA, MTA Repair HP, and Biodentine (P<0.05). For the FL, ultrasonic activation did not alter the flow of MTA (P>0.05);however, it increased the flow MTA Repair HP and Biodentine (P<0.05). For the DC, the percentage values of dimensional change were higher when there was ultrasonic activation in all repair cements (P<0.05). For SL, there was a reduction in the percentage of the values in MTA and MTA Repair HP (P<0.05);however, there was no change in the values of Biodentine (P>0.05). Ultrasonic activation favored the release of calcium ions from all cements. The SEM analysis showed, in general, that the ultrasonic activation reduced and altered the particle shape of the cement. Conclusions. The ultrasonic activation interfered in the ST, DC, FL, ultrastructural morphology, and calcium release of the repair cements. However

关键词： Chilto fruits   Frozen pulps   Antioxidant   Microbiological stability   Sensorial characteristics  

摘要： The frozen fruit pulp market has shown suitable growth due to the current technology available, having broad market potential. This study aimed to evaluate the physicochemical, microbiological, functional, and sensorial characteristics of Solarium betaceum pulp (chilto pulp) with different skin colors (orange and orange-red) under storage at -18 degrees C during different periods: 0, 30, 60, 90 and 180 days. The pulps were stable micmbiologically during the entire storage time, according to food legislation. The physicochemical results indicate that all the frozen pulps of chilto fruits had values in conformity to identity and quality standards and had a high content of bioactive compounds, fibers, and proteins. The pulps presented a powerful antioxidant and antihyperglycemic activity demonstrated by in vitro tests, which gives it a functional value in addition to the nutritional value. The results of the sensory analysis showed a good acceptance of the pulps by consumers, particularly in attributes such as color, aroma, and texture. The chilto fruit pulp can store up to 180 days at -18 degrees C retaining the physicochemical, microbiological, functional, and sensorial characteristics similar to the fresh pulp. For this reason, it is considered an interesting post-harvest conservation method for the expansion and revalorization of native Argentine fruits.

关键词： Clinoptilolite   Milling   Crystal structure   Porous structure   Photocatalysis  

摘要： The Natural and H-form of clinoptilolite were subjected to mechanochemical treatment in water and in air. Initial and milled samples were studied using a combination of XRD, FTIR, XPS/UV-vis spectroscopies, SEM and low-temperature nitrogen ad-/desorption. Dry milling leads to the destruction of the crystalline structure, whilst milling in water partially maintains the crystalline structure with a meso- macroporous structure formed in both cases. Surface was enriched with impurity iron, whose oxygen-containing species served as photocatalytic centres. The milled samples exhibit an improved photocatalytic activity in the process of rhodamine B degradation under visible light.

关键词： Sulindac   Electrocrystallization   Sacrificial copper anode   Dinuclear copper(II)   Paddle-wheel structure  

摘要： The electrocrystallization, structural and magnetic characterization of a copper(II) complex with the anti-inflammatory drug sulindac [HSuln = 2-[(3Z)-6-fluoro-2-methyl-3-[(4-methylsulfanylphenyl)methylidene]inden1-yl]acetic acid], with formula [Cu-2(C20H16FO3S)(4)]center dot 3H(2)O, is reported. Single crystals were grown directly on the surface of a sacrificial copper wire and were suitable for X-ray diffraction analysis. The complex is a 1D polymeric coordination complex consisting of paddlewheel moieties, formed by four sulindacate units bridging two copper(II) ions, and three disordered water molecules occupying the voids in the unit cell, with axially connected units through the neighboring sulfinyl oxygen atom located in the phenyl moiety. The complex presents a strong antiferromagnetic exchange interaction. Variable temperature magnetic susceptibility displays an unusual increase in the magnetic moment with decreasing temperature from 60 to 30 K, which may be indicative of the presence of a small amount of a monomeric Cu(II) species or traces of molecular oxygen. The product was additionally characterized by FTIR, UV-Vis spectroscopy, and TGA/DTA-DSC.