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991.
992.
Ming Lu Yan-Ping Han Xin-Huai Zhao 《Sensing and Instrumentation for Food Quality and Safety》2018,12(2):728-735
Gelatin is an important protein-based hydrocolloid, providing excellent gelling properties in processed foods. Horseradish peroxidase (100 U/g protein), glucose oxidase (1 U/g protein), and glucose (0.025 mmol/g protein) were applied to cross-link bovine gelatin at 37 °C for 3 h, and the gelling properties of cross-linked gelatin were evaluated. Obviously, the cross-linking process did not change the composition of amino acids. The cross-linked gelatin had 39.2% increase in surface hydrophobicity, 54.7% increase in emulsion stability index, but 28.2% decrease in emulsifying activity index, in comparison with bovine gelatin. Laser scanning confocal microscopy observation indicated that cross-linked gelatin rather than bovine gelatin conferred better droplet stability on the generated emulsion after long-storage period of 48 h or 7 days. Moreover, cross-linked gelatin had decreased in vitro digestibility during pepsin hydrolysis (38.5%) and pepsin–trypsin hydrolysis (14.5%) than bovine gelatin. Finally, the gelling and melting temperatures of cross-linked gelatin were 2 °C higher than those of bovine gelatin. Overall, the cross-linking process of bovine gelatin led to easier gelation and improved heat resistance of the subsequently gels. 相似文献
993.
Kaili Xu Yantong Wang Ruiqing Shen Qingsheng Wang 《International Journal of Hydrogen Energy》2018,43(31):14859-14865
For treatment of aluminum dust, a wet dust removal system has been used worldwide. During treatment, aluminum dust is inhaled into a water tank of the dust collector. As hydrogen production reactions are likely to take place in the water tank, there exists a great risk of fire or explosion accidents associated with the wet dust removal system. Based on field research and laboratory experiments, Hydrogen Inhibition Method (HIM) by using CeCl3 solutions was proved capable of inhibiting reactions between aluminum dust and water. When the concentration of CeCl3 solutions reached 6.02 g/L, there was basically no hydrogen gas produced. SEM, EDS and XPS characterizations were used to assess the aluminum particles before and after being reacted with water or CeCl3 solutions, respectively. Shrinking core model was utilized to identify the corresponding chemical reaction kinetics. Additionally, a physicochemical mechanism was established to explain these phenomena. 相似文献
994.
As hydrogen production with a water electrolyzer is an effective way for renewable energy consumption, understanding the external electrical characteristics of water electrolyzer is of great significance for the modeling and simulation, system configuration, and control strategy of the system for hydrogen production by renewable energy. However, there are relatively fewer studies in this area. This paper presents the establishment of an experimental platform to conduct an experimental study on the static and dynamic voltage‐current characteristics and analyze the adjustability of the electric power of the traditional alkaline water electrolyzer, the relationship between the electrical characteristics and the electrolyte temperature, and operating point of the alkaline water electrolyzer. In addition, the mathematical fitting problem of the electrical characteristics of the alkaline water electrolyzer is discussed. The work could supply a reference to alkaline water electrolyzer intergrated application in renewable energy. 相似文献
995.
Pramodkumar D. Jadhav Yang Zuo Youn Young Shim Jianheng Shen Martin J. T. Reaney Ning Zhang Yong Wang 《International Journal of Food Science & Technology》2018,53(8):1972-1982
Linusorbs (LOs; a.k.a. cyclolinopeptides) are naturally occurring orbitides derived from flaxseed. These compounds consist of 8–10 amino acid residues, which are linked via an N ‐ to C‐terminal peptide bond with molecular masses of approximately 1 kDa. The LO circular structure makes them candidates for metal binding studies. Flaxseed extracts are known to suppress Pb and Cd toxicity. Hence, four metal salts surveyed include Zn(CH3COO)2, ZnSO4, Pb(CH3COO)2 and Cd(NO3)2 with pure LOs 1–5 . Proton NMR spectra indicated interaction of LOs with metal salts in solution and were used to determine impacts of methionine oxidation on interactions with metal ions. The methyl group of methionine S,S ‐ dioxide of related LOs did not show the same shift in the presence of Zn(CH3COO)2 and Pb(CH3COO)2 observed in their methionine S ‐ oxide analogues. Metal complexes were observed forming at 10?2 m to 10?4 m but not at lower concentrations (10?5 m to 10?8 m ). Mass spectrometry data confirmed that metal binding strength varied by metal in the order Zn(CH3COO)2<Pb(CH3COO)2<ZnSO4<Cd(NO3)2. 相似文献
996.
Dejing Chen Jingyuan Sun Weixue Dong Yixiao Shen Zhimin Xu 《International Journal of Food Science & Technology》2018,53(10):2335-2341
The effects of polysaccharides, theaflavins, thearubigins and theabrownin fractions of Zijuan tea on α‐glucosidase and blood glucose level and intolerance of hyperglycaemic mice were evaluated. The polysaccharides or theaflavins fraction exhibited greater inhibition rate of α‐glucosidase than acarbose positive control, thearubigins fraction or theabrownin fraction. The four fractions were delivered to the treatment mice through oval gavage each day for 15 days. The mice in polysaccharides and theaflavins high‐ and low‐dose and theabrownin high‐dose treatments significantly lowered their blood glucose levels while all the treatment mice gained body weight. The mice in polysaccharides, theaflavins and theabrownin high‐ and low‐dose treatments had greater glucose tolerance as well. Thus, the theaflavins and polysaccharides fractions of Zijuan tea effectively moderated the complications of hyperglycaemic mice. The lower effectiveness of thearubigins and theabrownin fractions may be caused by the highly polymerised polyphenolics which decreased their accessibility to α‐glucosidase and digestibility in mice. 相似文献
997.
Influence of light on the chroma of low pressure hydrogenation aviation kerosene was studied using different lights (ultraviolet light, infrared light, sunlight and no light) in the same environment full of oxygen. UV light with short wavelength has the largest influence. Coloring substances were isolated by adsorption on neutral alumina followed by ether extraction and identified by using infrared spectrum, elemental analysis and two-dimensional GC-MS. Oxygen-containing compounds are main coloring substances. Light can provide the required energy to convert unsaturated hydrocarbons and heteroatom compounds to phenols, quinones and ketones. 相似文献
998.
999.
Molecular Ordering: Selectivity of Threefold Symmetry in Epitaxial Alignment of Liquid Crystal Molecules on Macroscale Single‐Crystal Graphene (Adv. Mater. 40/2018) 下载免费PDF全文
1000.
Artificial Photosynthesis: Ni‐Nanocluster Modified Black TiO2 with Dual Active Sites for Selective Photocatalytic CO2 Reduction (Small 2/2018) 下载免费PDF全文