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In order to control diesel exhaust emission, CeO2-SnO2/Al2O3 (CTA) mixed oxides were prepared and coated on perforated stainless steel (SS) filter plates, and the catalytic activities were analyzed in this work. The CeO2-SnO2 (different compositions of Ce/Sn-2:8; 1:1; 8:2) composites and Al2O3 were prepared separately via a co-precipitation approach, and CeO2-SnO2/Al2O3 (CTA) mixed oxides were attained by mechanical mixing of 75 wt% CeO2-SnO2 composites with 25 wt% Al2O3. X-ray diffraction (XRD) and Raman spectroscopy were performed for all three CeO2-SnO2/Al2O3 (CTA) mixed oxides; the CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample confirmed the presence of cubic and tetragonal mixed faces, which enhances the redox nature (catalytic activities). Various characterizations such as high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), and a scanning electron microscope (SEM) were employed on CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample to investigate the structural, textural, compositional, and morphological properties. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample was coated on a perforated stainless steel (SS) filter plate via a simple, cost-effective, and novel method, and an exhaust emission test for various compression ratios (CR), injection pressure (IP), and load (L) was completed using an AVL Digas analyzer. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample, with a size of 10.22 nm and a high surface area of about 73 m2 g-1, exhibit appreciable catalytic properties.
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Polyphenols from plant sources are increasingly recognized as functional ingredients with multiple health benefits. Finger millet (Eleusine coracana), a major millet grown in Asia and Africa is a significant source of polyphenols. The extraction of polyphenols from millets which are under-utilized has received less research attention compared to other plant matrices. Therefore, the present study was carried out to identify an effective method of extracting the polyphenols from finger millet (v. GPU 28) seed coat (FMSC). Two eco friendly methods namely ultrasonication (UA) and enzyme treatment followed by ultrasonication (EUA) were compared with the conventional heat reflux method (HR). The polyphenolic profile and content along with the antioxidant potential of the extract were evaluated. Phenolic yield increased 2.3 fold using EUA with xylanase (XUA) compared to heat reflux extraction (HR). However, yield with UA was equivalent to the conventional method. Total flavonoids increased 1.4 fold in UA and 1.3 fold in XUA, similarly, tannins also showed a significant increase (1.1 fold in UA and 1.2 fold in XUA). FTIR spectra revealed the presence of all phenolic functional groups and ESI-MS showed 80% similarity in the individual polyphenols in the extracts. Catechins, luteolin and cyanidin were identified in the UA and XUA treated samples, whereas, shikimic acid derivatives- caffeoyl and di caffeoyl were present only in XUA extracts. This is the first report on enhanced extraction of polyphenols from FMSC using a combination of enzyme treatment and ultrasonication, providing a green technology for utilization of polyphenols in nutraceuticals and functional foods.
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The growing commercial importance of xylooligosaccharides is based on their beneficial health properties, particularly their ability to stimulate the growth and activity of intestinal bacteria such as Bifidobacterium and Lactobacillus species. Xylooligosaccharides are less sweet, acid, and heat stable, with low recommended levels of intake compared to other oligosaccharides. In view of the consumer demand for foods with low sugar, low fat, and high fiber contents, they are suitable for incorporation into bakery products. In this study, we have developed wheat-based cookies incorporated with xylooligosaccharides at 5%, 10%, and 15% levels. The nutritive value and physicochemical properties of the cookies changed with xylooligosaccharides incorporation; both crude fiber and dietary fiber contents increased by 14% and 35%, respectively, in the enriched cookies. The moisture levels increased with increase in the percentage of xylooligosaccharides incorporated. Cookies with 5% xylooligosaccharides were found most acceptable, although the color was slightly darker compared to the control, while cookies with 10% and 15% xylooligosaccharides were softer and darker and therefore less acceptable. Enrichment with xylooligosaccharides at 5% provided a product stable for 21 days at room temperature (25 ± 2â). The storage stability of cookies with higher levels of xylooligosaccharides was less than the 5% xylooligosaccharides cookies and control. The retention of the prebiotic xylooligosaccharides in the products was relatively high (74%).
Assuntos
Fenômenos Químicos , Alimentos Fortificados/análise , Glucuronatos/análise , Promoção da Saúde , Valor Nutritivo , Oligossacarídeos/análise , Prebióticos , Cor , Fibras na Dieta/análise , Conservação de Alimentos , Alimento Funcional/análise , Glucuronatos/química , Humanos , Oligossacarídeos/química , TriticumRESUMO
A family of new 1D, 2D, and 3D coordination networks based on metal-pyridylphosphonates have been synthesized under hydro(solvo)thermal conditions. Zn(3-pyridylphosphonate)(bromide), 1, adopts a 1D ladder structure, while Co(4-pyridylphosphonate)(H(2)O)(3), 2, adopts a 2D grid structure. [Cu(2)(4-pyridylphosphonate)(2)]-2H(2)O, 3, [Cd(3-pyridylphosphonate)(2)]-DMSO, 4, Cd(4-pyridylphosphonate)(2), 5, and Cd(ethyl 4-pyridylphosphonate)(2), 6, all adopt 3D framework structures. While 3 possesses open channels that are occupied by water molecules, 4 exhibits cavities that accommodate DMSO guest molecules. The present work demonstrates that interesting open frameworks can be readily synthesized on the basis of metal pyridylphosphonates. Crystal data for 1: monoclinic space group C2/c; a = 15.267(4), b = 11.903(2), c = 10.380(2) A; beta = 98.68(2) degrees; Z = 8. Crystal data for 2: monoclinic space group P2(1)/c; a = 9.634(12), b = 7.611(9), c = 11.901(1) A; beta = 97.830(2) degrees; Z = 4. Crystal data for 3: triclinic spacegroup P one macro; a = 7.464(8), b = 9.203(1), c = 11.602(2) A; alpha = 100.289(1) degrees; beta = 104.532(1) degrees, gamma = 94.569(1) degrees; Z = 2. Crystal data for 4: tetragonal space group I4(1)/a; a = 15.114(2), b = 15.114(2), c = 13.128(3) A; Z = 8. Crystal data for 5: monoclinic space group P2(1)/c; a = 8.344(2), b = 10.589(2), c = 14.384(3) A; beta = 91.77(3) degrees; Z = 4. Crystal data for 6: monoclinic space group P2(1)/n; a = 5.606(1), b = 11.198(1), c = 14.176(2) A; beta = 94.518(1) degrees; Z = 2.
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Three-dimensional open frameworks [Co2(nicotinate)4(mu-H2O)]-CH3CH2OH-H2O, 1, and [Ni2(nicotinate)4(mu-H2O)]-CH3CH2OH-H2O, 2, were obtained by hydro(solvo)thermal reactions between 3-cyanopyridine and cobalt(II) nitrate and nickel(II) perchlorate, respectively. Both 1 and 2 exhibit complicated 3-D structures based on [M2(nicotinate)4(mu-H2O)] (M = Co or Ni) building blocks and possess open channels that are occupied by removable solvent molecules. 3-D open frameworks [M2L4(mu-H2O)]-HL-(H2O)x (where M = Co, x = 2, 3, and M = Ni, x = 1, 4, and L = trans-3-(3-pyridyl)acrylate) were similarly prepared with trans-3-(3-pyridyl)acrylic acid in place of 3-cyanopyridine. Compounds 3 and 4 are isostructural and exhibit network topologies similar to that of 1 with open channels occupied by disordered trans-3-(3-pyridyl)acrylic acid and water guest molecules. Crystal data for 1: triclinic space group Ponebar, a = 10.534(1) A, b = 11.907(1) A, c = 14.046(1) A, alpha = 106.645(1) degrees, beta = 101.977(1) degrees, gamma = 112.078(1) degrees, and Z = 4. Crystal data for 2: tetragonal space group P4/ncc, a = 20.089(1) A, c = 14.016(1) A, and Z = 4. Crystal data for 3: monoclinic space group C2/c, a = 14.082(2) A, b = 15.278(2) A, c = 18.537(2) A, beta = 105.360(2) degrees, and Z = 2. Crystal data for 4: monoclinic space group C2/c, a = 14.082(1) A, b = 15.250(1) A, c = 18.606(1) A, beta = 106.747(1) degrees, and Z = 2.
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Cobalto/química , Niacina/análogos & derivados , Niacina/síntese química , Níquel/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Niacina/químicaRESUMO
Three new, mixed-valent layered vanadyl phosphates, Ag(0.43)VOPO(4).2H(2)O (AgVPO), Cu(0.16)VOPO(4).2.5H(2)O (CuVPO), and Zn(0.11)VOPO(4).2.5H(2)O (ZnVPO), have been synthesized hydrothermally and their structures determined by single-crystal X-ray diffraction: AgVPO is triclinic, space group P&onemacr;, a = 6.287(1), b = 6.283(1), and c = 13.240(1) Å, alpha = 80.98(1), beta = 86.58(1) and gamma = 90.00(1) degrees, Z = 4; CuVPO is triclinic, space group P&onemacr;, a = 6.260(2), b = 6.249(3), and c = 7.257(1) Å, alpha = 83.62(3), beta = 73.99(2), and gamma = 90.13(4) degrees, Z = 2; ZnVPO is triclinic, space group P&onemacr;, a = 6.252(1), b = 6.248(2), and c = 7.339(3) Å, alpha = 83.24(4), beta = 73.93(2), and gamma = 90.00(2) degrees, Z = 2. The structures are related to that of VOPO(4).2H(2)O. Metal powders have been found to be effective both as reductants and as countercations.