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关键词： ceramic compositions   clay   Guinea   physicochemical characteristics  

摘要： To evaluate their potential uses in ceramic compositions, two different types of abundant clays from Kindia (Guinea Conakry), denoted ABD and ARD, were characterized with the chemical and mineralogical compositions, the specific surface area, the plasticity index, the particle size distribution, and the thermal behavior. Kaolinite and muscovite are the main clay minerals that are identified. Besides, non-plastic minerals are large amount of quartz with a small particles size, goethite, hematite, anatase, and a small quantity of gibbsite. The two clays have a high plasticity index that is consistent with the small particle size and the broad size distribution. During heating, the fluxing behavior of the two clays induces a significant densification that is favored by the muscovite mineral combined with the reactive fine quartz. Besides, the firing shrinkage is limited to values of 4.5% and 3.5% for ABD and ARD respectively. In the objective of manufacturing ceramics, the two clays present the required properties. They present a sufficient plastic index in the green state, and after firing they lead to dense ceramics with an interesting bright color. The limited firing shrinkage is favorable to maintain the dimensional stability of vitrified ceramics as porcelain.

关键词： acylation   glycation   physicochemical properties   soy protein isolate   structure  

摘要： This study examined the effects of different sequential treatments of dextran glycation and succinic anhydride acylation on the structure and physicochemical properties of soy protein isolate (SPI). The tested properties included electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy, endogenous fluorescence spectroscopy, surface hydrophobicity (H-0), free sulfhydryl (-SH), solubility, interfacial properties, rheological properties, and scanning electron microscope (SEM). The results show that the two treatments significantly improved the structure and functional characteristics of the SPI. The order of the methods had an important effect on the SPI. The lowest H-0 (231.76 +/- 11.92), the highest free -SH content (3.09 +/- 0.09 mu mol/g), and the highest solubility at pH = 7 (77 +/- 3.97%) were obtained when the acylation treatment was followed by the glycation treatment. Emulsification, emulsion stability, foaming, and foam stability were also the highest. Glycation and acylation caused the viscosity coefficient (k) of the SPI solution to decrease compared with SPI alone, but the flow index (n) value increased, and the sum G' value of the conjugate system decreased as gel time increased. SEM showed that its microstructure has changed significantly. Therefore, this research provided an effective method for improving the functional characteristics of SPI and had potential industrial application prospects. Practical Application Glycation and acylation of soybean protein isolate improved the chemical modification method of protein, improved the functional properties of soybean protein, widened its application in food and materials, and provided a new idea for the further development and utilization of soybean protein.

关键词： milling yields   one-pass drying   rice cultivars   rice quality  

摘要： Background and objectives The 915 MHz industrial microwave has a great penetration depth relative to the 2.45 GHz microwave and holds the potential to achieve one-pass drying of deeper rice beds within a short drying duration. The objective of this research is to determine the effect of microwave specific energy on the quality, functional, and physicochemical properties of different rice cultivars. Two rice cultivars were used: a medium grain cultivar (Titan) and a long grain hybrid cultivar (XL753) from two different locations (Burdette and Carlisle). Rice samples at harvest moisture content of 20% wet basis were dried using the 915 MHz industrial microwave at specific energies ranging from 360 to 720 kJ per kg of initial wet grain mass (kJ.[kg-grain](-1)). Rice physicochemical and functional properties were analyzed. Findings Results indicate that specific energy had a significant effect (p-value < 0.0001) on moisture removal and head rice yield. On average, increasing specific energy (drying duration 3-4 min, power 4-6 kW) resulted in increased moisture points removed from 2.5% to 7.3% and 3.7% to 7.5% for long grain hybrids and medium grain cultivars, respectively, while head rice yield decreased. Setback and final viscosities increased while peak viscosity decreased with increasing specific energies. Kernel surface lipid and protein content slightly decreased with increasing specific energies, although specific energy did not have a significant effect on these responses. Resistant starch content decreased with increasing specific energy for hybrid rice. Water and oil absorption capacities varied at different specific energies. The most desirable specific energy for moisture removal that maintains rice quality characteristics (relative to control samples) was 525 kJ.[kg-grain](-1). Conclusions The 915 MHz industrial microwave has the potential to achieve one-pass drying of rice. A study of the best specific energy for drying different cultivars of rice using thi

关键词： absorption   biochar   pyrolysis temperature   Turkish gall residue  

摘要： How to correctly and scientifically dispose of medicine residue on the basis of protecting the environment is an urgent problem to be solved due to the continuous generation of a large amount of waste medicine residue. In this paper, the application of waste medicine residue (large volume produced each year) as a precursor in producing a biochar that could adsorb Pb ion was reported. Biochar is a stable, aromatic, porous substance that is rich in carbon and prepared through pyrolysis of waste biomass under anaerobic conditions. In this study, medicine residue was used as raw material, and high-temperature sintering furnace was used to prepare medicine slag biochar at different temperatures of 200 degrees C, 300 degrees C, 400 degrees C, 500 degrees C, and 600 degrees C. The resulting biochar was characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), specific surface area analysis, field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Raman spectroscopy (RS). Experimental results showed that with the increase in pyrolysis temperature, the biochar structure was destroyed. The yield decreased as the temperature gradually decreased from 81.69% to 33.90%. With the increase in temperature, the pH, the ash, and the fixed carbon gradually increased, whereas the number of surface functional groups decreased. The quasi second order kinetic equation can better fit the kinetic characteristics of adsorbing Pb ion by biochar. In general, this study provides a valuable method for recycling medicine residue.

关键词： Mixtures  

摘要： In this study, a mixture of salep and chia seed powder (CSP) at different ratios was used as a stabilizer in the production of ice cream. The effect of the mixtures was determined on the physical, chemical, color, rheological, thermal properties, instrumental hardness, and consumer acceptance properties of the ice cream samples. The viscosity, consistency coefficient, lightness (L*), whiteness index, Tm ' (midpoint and offset), heat ice freezing, and melting values increased in the sample containing 0.6% salep and 0.2% CSP compared to the control sample and then decreased in accordance with the increment of CSP. The highest hardness value was determined in the sample containing CSP (0.8%). The control sample and sample containing 0.6% salep/0.2% CSP had the highest consumer acceptance scores. It was determined that 0.2% CSP could be used with salep to decrease the consumption of orchid species and to improve various quality properties of ice creams. Practical applications Salep (Orchidaceae family) is generally used as a stabilizer in ice cream, and species of salep is been extinction day to day. This study indicated that the usage of the mixture of salep and chia seed powder can improve the quality properties of ice creams. Consequently, the mixture of salep (75%) and chia seed powder (25%) could be used as a stabilizer to reduce using salep and to protect species of salep to improve the quality properties of ice cream.

关键词： Protein fortification   Cookie   Isolated soybean protein   Whey protein   Physicochemical   Consumer acceptability  

摘要： A high-protein diet has a variety of beneficial effects and mixing isolated soybean protein (ISP) with whey protein (WP) reported to increases health and functional advantages. The objective of this study was to determine an adequate ratio for mixing these two proteins by evaluating the physical and sensory properties of protein-fortified samples. Samples with 5 different ratios of ISP to WP ranging from 100:0 to 0:100 were prepared. Proximate composition, density, spread factor, hardness and color values of five samples were measured and consumer acceptance test were conducted by 117 panelists to evaluate physicochemical and sensory properties of protein-fortified cookies. In a consumer acceptance test, the combination of ISP and WP increased consumer acceptance, and the highest overall acceptance was obtained when ISP and WP were used in a one to one ratio. As the ISP content increased, the density was higher, and the spreadability was the lowest. On the other hand, as WP increased, hardness increased significantly, and L*, a* and b* values increased (p < 0.05).The result of this study may facilitate the development of protein-enriched foods, which have various health benefits.

关键词： thermal barrier coating   samarium oxide   zirconium oxide   hafnium oxide  

摘要： In continuation of our systematic study of the options of the development of high-performance thermal barrier coatings based on three-component ceramic materials comprising rare-earth oxides, we report on the effects of component concentrations on the thermophysical properties of ceramics based on the Sm2O3-ZrO2-HfO2 system. Samarium oxide is found to stabilize these ceramics when its concentration is higher than 22.5 mol % and zirconium oxide concentration is lower than 56.7 mol %. The temperature coefficient of linear expansion (TCLE) of the studied ceramic materials in the temperature range 20-1400 degrees C can reach alpha(L) = (10.4 +/- 0.6) x 10(-6) with acceptable values of the thermal conductivity coefficient at a level of 0.56-0.84 W/(m K).

关键词： Agrocybe cylindracea   Heteroglycans   Structural characteristic   Viscosity and morphology  

摘要： Polysaccharide from Agrocybe cylindracea has been demonstrated to exhibit excellently biological functions, but insufficient understanding of its physicochemical property and fine structure limits its wide application and development. In the present study, two water-soluble heteroglycans, a high molecular weight (SACP-40) and a low molecular weight (SACP-80), were isolated from the fruit bodies of A. cylindracea by hot water extraction and gradient ethanol precipitation. There was little difference in their physicochemical properties, including major chemicals and monosaccharide compositions. Rheological measurements revealed SACP-80 was a typical pseudoplastic fluid with shear thinning behavior at the concentration of 3.0%, whereas exhibited a near Newtonian fluid at lower concentration. SEM observation suggested SACP-80 showed micro-spherical shapes loosely attached to fibrous filament in its surface. Besides, methylation and 1D/2D NMR analysis indicated that SACP-80 was a branched heteroglycan with a backbone composed of beta-(1 -> 6)-glucopyranosyl, alpha-(1 -> 6)-galactopyranosyl and alpha-(1 -> 2,6)-glucopyranosyl residue at a ratio of 3:1:1. This work provides a theoretical basis for gaining insight into the relationship between the fine structure and viscosity of polysaccharide from A. cylindracea, which could further guide its functional studies and advance the potential application in food and biomedicine industries.

关键词： Vaccine(s)   Stability   Analysis   Analytical ultra-centrifugation   Field-flow fractionation (FFF)   Light scattering (static)   Surface plasmon resonance (SPR) spectroscopy  

摘要： Upscaling the production capacity of inactivated poliovirus vaccines (IPV) is urgently needed to eradicate polio worldwide. For the development of a robust manufacturing process for IPV, the impact of stresses on the properties of the poliovirus during manufacturing needs to be carefully evaluated. In this study, the physicochemical properties of Sabin poliovirus after low pH exposure were analyzed by asymmetrical flow field-flow fractionation coupled to multi-angle laser light scattering (AF4-MALS), sedimentation velocity analytical ultracentrifugation (SV-AUC), transmission electron microscopy (TEM), dynamic light scattering (DLS) and surface plasmon resonance (SPR). Low pH stress caused structural changes and aggregation of inactivated poliovirus virions, whereas degraded virion particles would not revert to native virions even after neutralization. Importantly, a complete loss of the D-antigenicity of IPV by low pH stress, followed by neutralization, was observed in SPR. These results suggest that the exposure of poliovirus particle to low pH stress would induce irreversible denaturation and aggregation of virus particles and lead to the loss of D-antigenicity;thus, low pH stress during the manufacturing of poliovirus vaccine should be minimized. The analytical methods above can be efficiently utilized in the development of high-integrity manufacturing processes and high-quality vaccines. (c) 2020 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.

关键词： 16S rRNA   bacterial diversity   chromium   Illumina   industrial treatment   leather manufacturing   water quality indicators  

摘要： Tanneries are an important industrial sector in Ethiopia;consequently, gaps in wastewater treatment process performance need to be identified as the country increases its emphasis on compliance. A case study was conducted to evaluate physicochemical and microbial water quality at a tannery near Addis Ababa. The treatment process was designed for the following: sulfide oxidation;biological oxygen demand reduction;and chromium removal. While some of Ethiopia's standards for industrial wastewater treatment were met through treatment, effluent COD, sulfide, total nitrogen, and total chromium guidelines were not. 16S rRNA gene analysis was used to evaluate the microbial community composition across the treatment train. The results show that common ruminant phyla were dominant throughout, with Firmicutes and Bacteroidetes comprising 77% to 82% relative abundance. The Firmicutes Clostridium increased consistently in relative abundance with treatment, comprising 39% to 61% of the total bacterial community in the effluent. Improved treatment is needed to meet environmental and public health goals. Practitioner Points Case Study of tannery wastewater treatment in Ethiopia shows ineffective treatment of chemical pollutants. Microbiological pollutants from tannery wastewater systems can introduce agents of importance to public health The microbiological composition of tannery influent, mixed liquor and effluent contains mostly four bacterial phyla lead by Firmicutes. Most pathogenic bacterial genera found in the tannery wastewater treatment system became a decreasing percentage of the total population. Clostridium comprises up to 61% of the effluent bacterial population and deserves further evaluation to better understand the consequences of its dominance.