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991.
Zhipeng Li Dexue Ma Yiyang He Siqi Guo Fuguo Liu Xuebo Liu 《Molecules (Basel, Switzerland)》2020,25(23)
Protein-polysaccharide covalent complexes exhibit better physicochemical and functional properties than single protein or polysaccharide. To promote the formation of the covalent complex from lactoferrin (LF) and beet pectin (BP), we enhanced the Maillard reaction between LF and BP by using an ultrasound-assisted treatment and studied the structure and functional properties of the resulting product. The reaction conditions were optimized by an orthogonal experimental design, and the highest grafting degree of 55.36% was obtained by ultrasonic treatment at 300 W for 20 min and at LF concentration of 20 g/L and BP concentration of 9 g/L. The formation of LF-BP conjugates was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) spectroscopy. Ultrasound-assisted treatment can increase the surface hydrophobicity, browning index, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free radicals scavenging activity of LF due to the changes in the spatial configuration and formation of Maillard reaction products. The thermal stability, antioxidant activity and emulsifying property of LF were significantly improved after combining with BP. These findings reveal the potential application of modified proteins by ultrasonic and heat treatment. 相似文献
992.
Xinming Zhang Tianzhan Zhang Shuanli Guo Yang Zhang Rongtian Sheng Ruimeng Sun Lixia Chen Ruijuan Lv Yanfei Qi 《Molecules (Basel, Switzerland)》2020,25(24)
Fungal infections pose a serious threat to human health. Polyoxometalates (POMs) are metal–oxygen clusters with potential application in the control of microbial infections. Herein, the Ag3PW12O40 composites have been synthesized and verified by Fourier transform infrared (FT-IR) spectrum, transmission electron microscopy (TEM), scanning electron microscope (SEM), elemental analysis, and X-ray diffraction (XRD). The antifungal activities of Ag3PW12O40 were screened in 19 Candida species strains through the determination of minimum inhibitory concentration (MIC) by the microdilution checkerboard technique. The minimum inhibitory concentration (MIC50) values of Ag3PW12O40 are 2~32 μg/mL to the Candida species. The MIC80 value of Ag3PW12O40 to resistant clinical isolates C. albicans HL963 is 8 μg/mL, which is lower than the positive control, fluconazole (FLC). The mechanism against C. albicans HL963 results show that Ag3PW12O40 can decrease the ergosterol content. The expressions of ERG1, ERG7, and ERG11, which impact on the synthesis of ergosterol, are all prominently upregulated by Ag3PW12O40. It indicates that Ag3PW12O40 is a candidate in the development of new antifungal agents. 相似文献
993.
Jiao Jiajia Li Hao Lin Wen Wang Rui Meng Zihan Guo Weibin Zhao Shengqiu Li Junsheng Tang Haolin 《Journal of Solid State Electrochemistry》2020,24(3):771-779
Journal of Solid State Electrochemistry - Practical application of Li-S battery is limited by the fast capacity decay and low coulombic efficiency caused by the shuttling phenomenon. Modification... 相似文献
994.
An exceptional n-cycle in a Hom-finite triangulated category with Serre functor has been recently introduced by Broomhead,Pauksztello and Ploog.When n=1,it is a spherical object.We explicitly determine all the exceptional cycles in the bounded derived category D^b(kQ)of a finite quiver Q without oriented cycles.In particular,if Q is an Euclidean quiver,then the length type of exceptional cycles in D^b(kQ)is exactly the tubular type of Q;if Q is a Dynkin quiver of type E_m(m=6,7,8),or Q is a wild quiver,then there are no exceptional cycles in D^b(kQ);and if Q is a Dynkin quiver of type An or D_n,then the length of an exceptional cycle in D^b(kQ)is either h or h/2,where h is the Coxeter number of Q. 相似文献
995.
The Ramanujan Journal - Guillera and Zudilin proved three “divergent” Ramanujan-type supercongruences by means of the Wilf–Zeilberger algorithmic technique. In this paper we prove... 相似文献
996.
Science China Mathematics - In this study, we propose nonparametric testing for heteroscedasticity in nonlinear regression models based on pairwise distances between points in a sample. The test... 相似文献
997.
Optimization Letters - We study a bilevel programming problem (BLPP) with a maximin lower level problem which is non-smooth and sometimes even non-convex. We reformulate such a non-smooth BLPP as a... 相似文献
998.
Kenna L. Salvatore Diana M. Lutz Dr. Haoyue Guo Dr. Shiyu Yue Joceline Gan Dr. Xiao Tong Dr. Ping Liu Dr. Esther S. Takeuchi Dr. Kenneth J. Takeuchi Dr. Amy C. Marschilok Dr. Stanislaus S. Wong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(42):9389-9402
Solution-based, anionic doping represents a convenient strategy with which to improve upon the conductivity of candidate anode materials such as Li4Ti5O12 (LTO). As such, novel synthetic hydrothermally-inspired protocols have primarily been devised herein, aimed at the large-scale production of unique halogen-doped, micron-scale, three-dimensional, hierarchical LTO flower-like motifs. Although fluorine (F) doping has been explored, the use of chlorine (Cl) dopants is the primary focus here. Several experimental variables, such as dopant amount, lithium hydroxide concentration, and titanium butoxide purity, were probed and perfected. Furthermore, the Cl doping process did not damage the intrinsic LTO morphology. The analysis, based on interpreting a compilation of SEM, XRD, XPS, and TEM-EDS results, was used to determine an optimized dopant concentration of Cl. Electrochemical tests demonstrated an increased capacity via cycling of 12 % for a Cl-doped sample as compared with pristine LTO. Moreover, the Cl-doped LTO sample described in this study exhibited the highest discharge capacity yet reported at an observed rate of 2C for this material at 143mAh g−1. Overall, these data suggest that the Cl dopant likely enhances not only the ion transport capabilities, but also the overall electrical conductivity of our as-prepared structures. To help explain these favorable findings, theoretical DFT calculations were used to postulate that the electronic conductivity and Li diffusion were likely improved by the presence of increased Ti3+ ion concentration coupled with widening of the Li migration channel. 相似文献
999.
Xiaoke Song Dr. Jun-Peng Wang Dr. Yan Song Prof. Tao Qi Prof. Guo Liang Li 《ChemistryOpen》2020,9(3):272-276
Camouflage and wound healing are two vital functions for cephalopods to survive from dangerous ocean risks. Inspired by these dual functions, herein, we report a new type of healable mechanochromic (HMC) material. The bifunctional HMC material consists of two tightly bonded layers. One layer is composed of polyvinyl alcohol (PVA) and titanium dioxide (TiO2) for shielding. Another layer contains supramolecular hydrogen bonding polymers and fluorochromes for healing. The as-synthesized HMC material exhibits a tunable and reversible mechanochromic function due to the strain-induced surface structure of composite film. The mechanochromic function can be further restored after damage because of the incorporated healable polyurethane. The healing efficiency of the damaged HMC materials can even reach 98 % at 60 °C for 6 h. The bioinspired HMC material is expected to have potential applications in the information encryption and flexible displays. 相似文献
1000.
Bin‐Wen Liu Xiao‐Ming Jiang Bing‐Xuan Li Hui‐Yi Zeng Guo‐Cong Guo 《Angewandte Chemie (International ed. in English)》2020,59(12):4856-4859
A large nonlinear optical (NLO) coefficient and a wide band gap are two crucial but contradictory parameters that are difficult to achieve simultaneously in a single infrared (IR) NLO compound. A salt‐inclusion chalcogenide (SIC), Li[LiCs2Cl][Ga3S6] ( 1 ), was prepared that presents a nanosized tunnel framework constructed from monotype chalcogenide tetrahedra. Highly oriented covalent GaS4 tetrahedra in the host lead to a moderate second harmonic generation response (0.7 AgGaS2), and ionic guests effectively broaden the band gap to the widest value (4.18 eV) among all IR NLO chalcogenides, thereby achieving a remarkable balance between NLO efficiency and band gap. 相似文献