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关键词： x-ray fluorescence analysis   microscopic analysis   chemical composition   glazed ceramics   alkaline glaze   lead glaze  

摘要： Aphysicochemical analysis was undertaken of fragments of medieval glazed ceramic found at different times in medieval towns located in the Chui, Talas, and Kochkor Valleys of Kyrgyzstan. The samples of glazed ceramic were studied by means of x-ray fluorescence and microscopic analyses. The physicochemical studies of the ceramic glaze from different archaeological complexes on the territory of Kyrgyzstan made it possible to identify the colorants and their features as well as the coloring technology and to note important moments in the historical development of the Gonchar crafts associated with the history of glazed ceramics in the countries of Central Asia.

关键词： bacterial community   desertification   grassland   soil aggregation   Tibetan Plateau  

摘要： The aim of this study was to evaluate the relationships among changes in the soil microstructure, soil physicochemical traits and microbial communities during desertification. Soil samples were collected from grasslands at different stages of desertification, from an area of the Tibetan Plateau. Soil aggregate fractionation and soil physicochemical properties were analysed using standard methods, and the abundance and diversity of bacteria associated with different aggregate fractions were estimated by quantitative PCR and Illumina Miseq amplicon sequencing. Sequential changes in response to desertification stages were detected in the analysed features. For instance, soil nutrients, microbial biomass C and N, water content and pH initially changed during the light desertification stage;then, the soil aggregation decreased during the intermediate stages;and finally, bacterial abundance and diversity decreased during heavy and severe desertification stages. During grassland desertification, vegetation coverage positively influenced soil aggregation by affecting soil properties (e.g., pH and SOC), whereas bacterial communities in FMi (free microaggregates) and FSC (free silt and clay) were negatively related to soil aggregation. This study reports novel information concerning the desertification process and the sequential modification of soil traits and interactions among soil physical properties (aggregate composition), soil nutrients and the soil microbial community in the grasslands of the Tibetan Plateau. Highlights Bacterial community was more sensitive in macroaggregates than in microaggregates. Composition of small macroaggregates and associated bacteria changed during desertification. Bacterial community in microaggregates, silt and clay negatively affected aggregation. Vegetation coverage affected aggregation by changing soil traits and bacterial community.

关键词： atherogenicity index   cholesterol   fat   lipid oxidation   longissimus muscle   sheep  

摘要： Marine microalgae of the genus Schizochytrium can be used in the diet of sheep a source of protein and energy and changing meat composition essentially due to its high content in docosahexaenoic acid (DHA). The objective was to evaluate the best inclusion level of marine microalgae meal in the lamb diet on the performance, carcass traits and meat quality. A total of thirty-two uncastrated Ile de France lambs with an initial average body weight (BW) of 20 +/- 0.2 kg were distributed in a completely randomized design with eight replicates and four treatments [marine microalgae meal inclusion at 0 (control), 2;4 and 6% in dry matte (DM)]. Marine microalgae meal inclusion in the diets of lambs reduced (P <= 0.05) DM intake, average daily gain, ruminal papilla height and width, meat cholesterol, C18:0, C18:1n-9, C18:2n-6, Sigma MUFA:Sigma SFA ratio, Sigma n-6 and Delta 9-desaturase-C16 activity of longissimus muscle. However, the marine microalgae meal increased (P 0.05) the feeding conversion, liver weight, meat lipid oxidation, C16:0, C17:0, C18:1n-7, 18:2 c9-t11 (CLA), C20:5n-3 (EPA) and C20:6n-3 (DHA), Sigma PUFA, Sigma n-3, atherogenicity (AI) and thrombogenicity (TI) index, sigma Hypercholesterolemic (H) FA and Sigma PUFA:Sigma SFA ratio. The carcass weight and yield, most of the variables of physicochemical composition and other FAs were not affected (P > 0.05) by marine microalgae meal inclusion in the diet. The marine microalgae meal inclusion up to 6% level in Ille de France lambs' diet was not efficient because it reduced the DMI, performance and feeding efficiency of the animals and it worsen lipid oxidation and healthy meat compounds AI, TI and h:H indexes. However, regarding meat fat quality, the microalgae inclusion confirmed the hypothesis of improving EPA, DHA, Sigma n-3 and CLA concentrations and reducing meat total cholesterol.

关键词： Alginate   Magnesium fluoridated hydroxyapatite   Composites   Cross-linking   Bioactivity  

摘要： The effect of magnesium fluoridated hydroxyapatite nanoparticles (Mg-FHA NPs) as ceramic species on the morphology, thermal and in vitro bioactivity properties of sodium alginate (SA) matrix was investigated. Preparation of cross-linked SA/FHA bio-nanocomposites (bio-NC)s was carried out under ultrasonic irradiations as fast and green conditions followed by cross-linking with CaCl2. The sonication influence on the dispersion of Mg-FHA in the alginate was studied thoroughly. Morphology images showed that the size of Mg-FHA NPs in the matrix reduced, considerably and the mean diameter of particles was estimated to be about 4 nm. The thermal stability of the alginate did not show significant changes by loading of 2, 6, and 10 wt% of Mg-FHA NPs. The bio-NCs exhibited the good ability of the formation of apatite in simulated body fluid. Mg-FHA growth on the surface of the samples was proved by a noteworthy increase in the phosphate absorption bands in FT-IR spectra, which shows the potential application of the obtained bio-NCs in tissue engineering.

关键词： Genipa americana   genipap fruit   natural dye   geniposide  

摘要： Research background. The current commercial scenario indicates an increase in the demand for natural dyes. Compared to synthetic dyes, natural ones have the advantage of being sustainable, making them of great interest for the food and cosmetic industries. The development of new natural dyes is necessary, as well as the carrying out of complementary research regarding the existing ones. Experimental approach. The present study aims to characterize the physicochemical and biological characteristics of the dye obtained from dehydrated endocarp of the genipap (Genipa americana) fruit, as well as perform the relevant stability and cytotoxicity tests. The chemical characterization was performed by HPLC-MS/MS analyses. The stability studies were carried out by spectrophotometry and cytotoxicity assays using cell culture and fluorometric methods. Results and conclusions. After dehydration and milling of the fruit endocarp, water was added to the obtained powder (in the ratio 4:1) to extract the dye. HPLC-MS/MS elucidated five compounds and confirmed the presence of the geniposide as its main compound. With the X-ray diffraction and electron microscopy analysis, we characterised the obtained powder as being amorphous and of porous structure with a variable size. The thermo-gravimetric analysis indicated a maximum loss of 61 % mass after exposure to a temperature range from 240 to 760 degrees C. The obtained blue dye was stable in the absence of light, at room temperature and had neutral pH. In the cytotoxicity assay, (95.0 +/- 1.3) % of viable human fibroblasts were observed after exposure to this dye. The genipap fruit can be a viable alternative to produce a natural blue dye, since it is easy to obtain and has very low toxicity in food, pharmaceutical or cosmetic products. Novelty and scientific contribution. This study demonstrates for the first time the physicochemical and biological properties of a natural blue dye from G. americana fruit.Y

关键词： poly-N,N-dimethyl-N,N-diallylammonium chloride   sodium lignosulfonate   sulfite and neutral-sulfite cellulose production methods   polyelectrolyte complex   potentiometric titration   filtration index   drilling mud  

摘要： The physicochemical properties of the initial components, poly-N,N-dimethyl-N,N-diallylammonium chloride, lignosulfonate, and polyelectrolyte complexes based on them, were studied. Optimal conditions and initial compounds were selected for polymerization of poly-N,N-dimethyl-N,N-diallylammonium chloride. The experiments were modeled with the STATISTICA 13 software package. The results from determination of the particle size of the samples of poly-N,N-dimethyl-N,N-diallylammonium chloride by laser diffraction are presented. Comparative analysis was made of the composition of the functional groups by means of the IR spectra of lignosulfonate sulfite and neutral sulfite methods of cellulose production A comparative analysis of the composition of the functional groups based on the IR spectra of lignosulfonate in the sulfite and neutral-sulfite method of cellulose production was undertaken. Potentiometric titration was used to study possible complexation of the lignosulfonate with Fe(77) ions and a polyelectrolyte complex based on modified lignosulfonate and poly-N,N-dimethyl-N,N-diallylammonium chloride. The effect of samples of the obtained polyelectrolyte complex on the filtration properties of drilling mud under aggressive temperature conditions was studied.

关键词： Physicochemical properties  

摘要： In this study, dried walnut kernels were processed by radiofrequency low pressure cold plasma (LPCP) treatment using normal air. Dried walnut kernels were treated with LPCP at different powers (20, 30, 40, and 50 W) and at different times (10, 15, and 20 min), and finally compared with the untreated sample. The tests performed in this study included microbial load reduction, decimal reduction time (D-value), peroxide value, moisture content, texture firmness, and color parameters. The LPCP treated samples compared with the control sample significantly reduced the microbial load (p < 0.05). The highest microbial log reduction was observed in 50 W for 20 min. Total viable count, coliform, and mold log reduction were equal to 1.09, 0.97, and 0.89 log CFU/g, respectively. D-values were also calculated, with the maximum reduction observed at 50 W. The lowest D-values for the total count, coliform, and mold were 19.66, 18.25, and 18.18 min, respectively. There was no significant difference between the treated and untreated samples in terms of peroxide value and firmness (p > 0.05). However, the treated samples' moisture content diminished with increasing power and LPCP exposure time (p < 0 .05). The result indicated that the LPCP darkened the treated samples' color. Practical Applications This study demonstrates the potential of low pressure cold plasma applications for the decontamination of dried walnut kernels. It is an appropriate alternative for product disinfection such as nuts, spices, aromatic plants, and other sensitive foods to high-temperature processing, due to the lack of waste production, low energy consumption, low cost, and keeping the physicochemical properties of products intact.

关键词： aqueous multi-component system   self-organization   nanoassociates   physico-chemical properties   fluorescent and UV characteristics   low concentrations   N-(phosphonomethyl)glycine   herbicide   bioeffects  

摘要： The relationship between non-monotonic concentration dependencies of the size of the dispersed phase (nanoassociates), physicochemical properties (specific electrical conductivity, pH), and fluorescence intensity (lambda(ex) 225 nm, lambda(em) 340 nm) of a multi-component dispersed system based on herbicide N-(phosphonomethyl)glycine and its effect on the development of some hydrobionts and on the inhibition of Triticum vulgare wheat root growth in the range of calculated concentrations 1.10(-19)-1.10(-3) g L-1 is established for the first time. The obtained results indicate that coherent changes in fluorescence intensity, physicochemical properties, and bioeffects are related to the rearrangement of nanoassociates which accompanies the dilution of the systems.

关键词： Pectin-rich dietary fiber   Citrus peel   Alkaline hydrogen peroxide   Homogenization   Physicochemical properties   Water-holding capacity  

摘要： Pectin-rich dietary fibers were prepared from citrus peel through alkaline hydrogen peroxide treatment (AHP-CF) or homogenization treatment (H-CF). Structural and physicochemical properties of the citrus fibers were evaluated and compared with a commercial one (Fiberstar). Results showed that pectin content of citrus fibers (CF) increased from 15.23% to 21.52% and 26.79% after AHP and homogenization treatment. AHP-CF had the highest water-holding capacity (WHC) (21.32 g/g), water-swelling capacity (WSC) (32.70 mL/g) and cation exchange capacity (CEC) (1.02 Meq/g) among the fibers. SEM results showed porous or wrinkled surface of the treated CFs. XRD and TG analysis indicated that AHP treatment increased the crystallinity and thermal stability of CF while homogenization treatment was the opposite. Besides, H-CF had similar chemical component, oil holding capacity and CEC with Fiberstar but higher WHC, WSC and thermal stability. These results suggested that AHP-CF and H-CF might be suitable to be an additive used in functional food.