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关键词： Starch  

摘要： Non-thermal plasma treatment is an emerging and effective starch modification technique. In this paper, plasma pretreatment was used to modify citrate naked barley starch for enhancing the ability of citric acid to access the starch structure. Plasma treatment did not alter the granule morphology and crystalline type of starch, but degraded the starch molecules and caused more short chains. Plasma pretreatment could etch the starch surface and depolymerize the starch molecules, which increased the accessibility of citric acid for uniform hydrolysis in the subsequent esterification reaction. Therefore, plasma pretreatment significantly promoted the structural and physicochemical modification of the citrate starch, including the enhancement of the degree of substitution, the short-range ordered degree and gelatinization temperatures, and the decreases in the molecular weight, long chains of amylopectin and pasting viscosities. Meanwhile, plasma pretreatment improved the efficiency of acid hydrolysis and decreased the enzymatic digestibility, so that it showed a higher resistant starch content in comparison with its corresponding citrate starch. This paper could provide a new insight into the lower digestion rate and improved functional properties of citrate starch.

关键词： Iron ore tailings   Concrete waste   Sludge from anodizing aluminum process   Lime production waste   Structure formation processes   Sustainable construction materials  

摘要： To replace completely natural raw materials were developed new sustainable concrete-like construction composites from 10 -40% iron ore tailings, 10-35% aluminum anodizing sludge, 25-30% concrete waste, and 15-25% lime production waste with mechanical and physical properties that meet the requirements of the Brazilian standards. The composition's axial compression resistance reached 4.49 MPa on the 3rd day and 11.24 MPa on the 730th day of cure. All mechanical, physical, and chemical properties of newly developed composites from these industrial wastes met Brazilian standards for producing construction materials like ecological. Dilatation coefficient values varied between 0.95 and 2.35% on the 3rd day of cure, and it ranged from 1.35 to 2.05% on the 730th day. The apparent specific mass increased during two years from 3.38 -3.67% to 3.47-3.75. Such properties met the requirements of Brazilian standards for producing sustainable road bases, bricks, and blocks. The studies of structure formation processes during 730 days of outdoor cure showed the synthesis of mainly amorphous sol-gel new formations with a slight inclusion of crystalline carbonate content. The main novelty of this research study is the scientifically and experimentally proven possibility to produce new environmentally clean construction composites only from four types of hazardous industrial waste to replace traditional natural raw materials like sand, gravel, crushed stone. The use of this laboratory study's results at the industrial level will reduce the irreversible destruction of nature by quarries of construction materials, noticeably improving our planet's sustainability. (c) 2021 Elsevier Ltd. All rights reserved.

关键词： adsorption   gas-adsorption crystallography   intermolecular interactions   metal-organic frameworks   pore environments  

摘要： For a better design of adsorbents, it is important to know the intermolecular interaction among adsorbates and host material, leading to improved guest selectivity and uptake capacity. In this study, we demonstrate the influence of the interaction among adsorbates and substrate, controlled by the pore environment and species of adsorbates, on the adsorption behaviour. We report the unique CO2 adsorption behaviour of MOF-205 due to distinct pore geometry. The precise analysis through gas-adsorption crystallography with molecular simulation shows that capillary condensation of CO2 in MOF-205 occurs preferentially in the large dodecahedral pore rather than the small tetrahedral pore, because the interaction of CO2 with MOF-205 framework is weaker than that among CO2 molecules, while Ar and N-2 are sequentially filled into two different pores of MOF-205 according to their size. Comparison of the materials with different pore environments reveals that the relative strength of the adsorbate-adsorbate and adsorbate-substrate interaction gives rise to different shapes of isotherms.

关键词： Design of experiments  

摘要： One of the basic principles of experimental design is blocking, which is an important factor in the treatment of the systematic spatial variability that can be found in the edaphic properties where agricultural experiments are conducted. Blocking has a mitigating or suppressing effect on the spatial dependence in the residuals of a model, something desirable in standard linear modeling, specifically in design models. Some computer programs yield a p value associated with the blocking effect in the analysis of variance table that in many cases has been incorrectly used to discard it, and although it may improve some properties of the analysis, it may affect the independence assumption required in several models. Therefore, the present research recommends the use of the H statistic associated with the corrected blocking efficiency to show the role of blocking in modeling with the incorporation of an additional advantage rarely considered related to the suppression or mitigation of spatial dependence. With the use of the Moran index, the spatial dependence of the residuals was studied in a simple factorial design in a completely randomized and blocking field layout, which evidenced the advantages of blocking in the mitigation or suppression of the spatial dependence despite the apparently little or no importance it seems to show in the analysis of variance table.

关键词： Monoterpenoids   Diastereomeric sulfoxides   Sulfone   Eutectic mixture   Thermochemistry   Supramolecular synthon  

摘要： The physico-chemical characteristics and crystal structure of newly synthesized isobornanyl sulfoxides and sulfone are presented. After purification, diastereomeric sulfoxides were obtained in a 2:1 eutectic ratio, which did not allow either separation or enrichment of the mixture. Based on thermochemical data, the form of the phase diagram of the system was reconstructed, showing that diastereomers have significantly different melting points. According to the X-ray data, the same supramolecular open- chain S = O center dot center dot center dot H-O synthon is built up in the crystals of diastereomeric sulfoxides. The isobornanyl sulfone crystal is formed in a complex way-two crystallographically independent molecules playing different roles in the formation of H-bonds. The IR spectra of a diastereomeric sulfoxides mixture demonstrate the averaging of the synthon-forming functional groups bands. In a counterbalance, the IR spectrum of isobornanyl sulfone shows a doubling of the key bands of synthon-forming functional groups belonging to homochirally homogeneous but crystallographically nonequivalent molecules. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Ziv-Aflibercept   Fc-fusion protein   Infusion bags   Stability study  

摘要： A range of biopharmaceutical products are used to target Vascular Endothelial Growth Factor (VEGF), including Eylea (R) (aflibercept, AFL) and Zaltrap (R) (ziv-aflibercept, ziv-AFL). The first is indicated for ophthalmological diseases such as neovascular (wet) age-related macular degeneration, while the second is used in the treatment of metastatic colorectal cancer. The stability of AFL in prefilled syringes has been widely studied;however, no research has yet been done on the stability of ziv-AFL in polyolefin infusion bags. Therefore, the purpose of the present research is to evaluate the stability of ziv-AFL (Zaltrap (R)) clinical solutions prepared under aseptic conditions in polyolefin infusion bags at two different concentrations, i.e. 4.0 and 0.6 mg/mL, and stored refrigerated in darkness at 2-8 degrees C for 14 days. With that aim, the ziv-AFL clinical solutions were assessed by analysing changes in its physicochemical and functional properties. The distribution of the particulates was studied over a range of 0.001-10 mu m by Dynamic Light Scattering (DLS);oligomers were analysed by Size-Exclusion High-Performance Chromatography with Diode Array Detection (SE/HLPC-DAD);the secondary structure of the protein was studied by far UV Circular Dichroism (CD) and the tertiary structure by Intrinsic Tryptophan Fluorescence (IT-F) and Intrinsic Protein Fluorescence (IP-F);charge variants were assessed by Strong Cation Exchange Ultra High-Performance Chromatography with UV detection (SCX/UHPLC-UV);functionality was evaluated by ELISA by measuring the biological activity as manifested in the extension of the immunological reaction of the ziv-AFL with its antigen (VEGF). Neither aggregation nor oligomerization were detected by the techniques mentioned above. Secondary and tertiary structures remained unchanged over the 14-day period, as did charge variants. The functionality observed initially was maintained along time. Therefore, it could be proposed that the ziv-AFL

关键词： Encapsulation   Bixin   Galactomannan   SEM   FT-IR   Thermoanalysis  

摘要： In this study, a spray drying technique was used to encapsulate bixin in the galactomannan polymer to give greater stability to this carotenoid. The microparticles were characterized using physical-chemical techniques, quantum chemical calculations, and evaluated the particle sizes, encapsulation efficiency, sta-bility, controlled release, and toxicological potential. The bixin was successfully encapsulated, with an average size of 5.55 +/- 0.50 mu m, and infrared spectroscopy showed no chemical reaction between bixin and galactomannan during the encapsulation process. The values for the encapsulation efficiency were higher than 90 %, indicating that galactomannan was a good encapsulating agent. A stability test revealed that microencapsulation provides significant protection for bixin. It was observed that the microparticles were capable of releasing the pigment homogeneously and gradually. The absence of toxicity of these ma-terials allows for their use within the food industry, since there is a need for new products that combine low toxicity, efficiency, and low cost. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Pseudo-Gruneisen parameter   Debye temperature   molecular interactions   binary liquid mixture  

摘要： The pseudo-Gruneisen parameter Gamma, effective Debye temperature theta(D), acoustic nonlinearity parameter B/A, internal pressure P-in and isobaric thermal expansion coefficient alpha have been evaluated for binary liquid mixtures of formamide (FA) and N-methylformamide (NMF) with 2-chloroethanol (2Cl-OH) at 298.15 K, 308.15 K and 318.15 K, over the entire concentration range. The excess pseudo-Gruneisen parameter Gamma(E), excess effective Debye temperature theta(E)(D), excess nonlinearity parameter(B/A)(E), excess internal pressure P-in(E) and excess isobaric thermal expansion coefficient alpha(E) were also calculated. The calculated values are reasonably satisfactory with the experimental results on sound propagation data of liquid mixtures. These physicochemical parameters play an important role in understanding of the significance of anharmonic and nonlinear behaviour with regard to intermolecular interactions in the liquid mixtures.

关键词： Acrylic bone cements   graphene oxide   silanization   improved mechanical properties   cytocompatibility  

摘要： Recently, different carbon-based nanomaterials have been used as reinforcing agents in acrylic bone cement formulations. Among them, graphene oxide (GO) has attracted the attention of scientific community since it could improve not only the mechanical properties but also the biocompatibility characteristics of these materials. However, using GO presents some drawbacks, such as its poor dispersion and lack of interaction with polymeric matrices, which should be prior resolved to achieve its optimal performance in acrylic bone cement. Thus, in this work, GO was treated with 3-methacryloxy propyl trimethoxy silane at various concentrations (1, 3 and 5 wt.%) to improve the interaction between the nanofiller and the poly (methyl methacrylate) matrix. Modified GO was incorporated at different percentages (0.1, 0.5 and 0.75 wt.%) into acrylic bone cement formulations and some properties were evaluated. The silanization process of the GO was confirmed by FTIR, TGA and EDX. The improvement in the mechanical performance was monitored on the compression properties whereas those related with biological properties were evaluated by osteoblast cell viability and hemocompatibility tests. Results suggest that using a 1 wt.% of the silane coupling agent, during surface treatment of GO, yields the best mechanical performance in this type of materials. It was also found that the presence of neat GO or silanized GO does not compromise the cytocompatibility and hemocompatibility of acrylic bone cement formulations.