FOOD CHEMISTRY
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2018
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IF 4.946
Dandan Li,Yao Zhang,Na Yang,Zhengyu Jin,Xueming Xu
This study aimed to improve induced electric field (IEF)-assisted hydrolysis of polysaccharide by controlling electrical conductivity. As the conductivity of reaction medium was increased, the energy efficiency of IEF was increased because of deceased impedance, as well as enhanced output voltage and temperature, thus the hydrolysis of guar gum (GG) was accelerated under IEF. Changes in weight-average molecular weight (Mw) suggested that IEF-assisted hydrolysis of GG could be described by the first-order kinetics 1/Mw ∝ k t, with the rate constant ( k ), varying directly with the medium conductivity. Although IEF-assisted hydrolysis largely disrupted the morphological structure of GG, it had no impact on the chemical structure. In comparison to native GG, the steady shear viscosity of hydrolyzed GG dramatically declined while the thermal stability slightly decreased. This study extended the knowledge of electrical conductivity upon IEF-assisted acid hydrolysis of GG and might contribute to a better utilization of IEF for polysaccharide modification.
研究领域:
食品科学
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生物化学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
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2019
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IF 5.399
Dan-Dan Li,Yang Tao,Ya-Ning Shi,Yong-Bin Han,Na Yang,Xue-Ming Xu
This study explored the impact of re-acetylation on induced electric field (IEF)-assisted hydrolysis of chitosan. Chitosan with different degree of deacetylation (DD) exhibited different charge content but similar electrical conductivity and output voltage of the electrolyte system, thus theoretically resulting in equivalent electro-processing efficiency. However, molecular and rheological measurements suggested that the hydrolysis rate decreased with an increase of DD. Re-acetylation had no significant effect on the molecular weight and viscosity of chitosan but damaged its granular and crystal structure, making chitosan chains more susceptible to the acid. The IEF-assisted hydrolysis of dissolved chitosan confirmed that the structural compactness of chitosan played a more important role on the hydrolysis than the charge content. This study extended current knowledge regarding the effect of charge content and structural compactness on IEF-assisted hydrolysis process, which contributed to the applications of IEF in biopolymer modification.
研究领域:
生物化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Na Yang,Zitao Zheng,Yamei Jin,Lingtao Zhang,Bimal Chitrakar,Xueming Xu
A continuant-flow induced electric field (IEF) apparatus was presented for the treatment of the milk. The electric field originated from the magnetic energy, and the volumetric heating of the milk was observed. The inactivation effect of IEF treatment on the milk inoculated with exogenous bacteria was investigated under different IEF strengths (11.11, 14.81 and 18.52 V/cm) and the duration (98, 131 and 196 s), IEF treatment reduced E. coli and S. aureus by more than 5.9 Log CFU/mL, and the damage to cell membrane caused by the non-thermal effects was observed via SEM images. Under 14.81 V/cm for 196 s, the total number of colonies in raw milk was reduced by 4.58 Log CFU/mL. The results demonstrated IEF treatment effectively preserved nutritional properties of milk, with no significant influence on protein content. Furthermore, IEF-treated milk exhibited smaller color changes, compared to conventional heat (CH) treatments, while the process did not lead to the accumulation of casein and milk fat globules. Because of rapid temperature rise and electroporation effect on microorganisms, it suggests that IEF treatment has the potential to dairy processing.
研究领域:
食品科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
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2019
·
IF 5.839
Dan-Dan Li,Na Yang,Yang Tao,En-Bo Xu,Zheng-Yu Jin,Yong-Bin Han,Xue-Ming Xu
The mechanism of induced electric field (IEF)-assisted acid hydrolysis was investigated by using guar gum, chitosan, and pectin as model polysaccharides . Roles of thermal and non-thermal effects were explored by temperature determination, HPSEC-MALLS-RI, SEM, FT-IR, XRD, and a rheometer. Results suggested that IEF affected the hydrolysis of polysaccharides by inducing thermal and non-thermal effects. Thermal effect contributed to the hydrolysis. As the excitation voltage increased, the thermal effect enhanced, with a temperature increased by about 25 °C after IEF (75 V) treatment for 4 h. Non-thermal effect, induced by the rapid and directional migration of charged species, varied with the electrical properties of the polysaccharides. It enhanced the hydrolysis of guar gum and pectin but negatively impacted the chitosan due to their different migration directions under IEF. IEF-assisted hydrolysis damaged the structural compactness of polysaccharides and significantly decreased the viscosity of their solutions. This study clarified the hydrolysis mechanism of polysaccharides under IEF, providing a theoretical guide for the application of IEF in the chemical modification of biopolymers.
研究领域:
食品科学
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化学工程
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生物技术
✓ 已验证
DOI
高影响因子
Nano Energy
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2020
·
IF 16.602
Meng Wang,Jialong Duan,Xiya Yang,Yudi Wang,Yanyan Duan,Qunwei Tang
Regulating the dynamic behavior of triboelectric charges between dielectric layer and metallic electrode is a promising solution to suppress charge screen effect and to improve the output performances of triboelectric nanogenerators (TENGs). Herein, the cutting-edge inorganic CsPbBr 3 perovskite is used as a dielectric material to tailor metal/perovskite Schottky junction for robust TENG applications. Arising from the induced electric field , the electron transfer from perovskite to metallic nanoparticle significantly promotes the charge accumulation at the bottom electrode, which in turn increases the overall power output of TENGs. After precisely regulating the barrier height of Schottky junction by means of optimizing noble metals (Ag, Au, and Pt) and fabricating the bulk Schottky junction, the electron drift-diffusion processes and the triboelectric charge storage behavior have been carefully optimized, achieving an enhanced power density of 3.31 W m −2 with an open-circuit voltage up to 240 V and a short-circuit current density of 4.13 μA cm −2 . This work may give new insights into the dynamic behavior of triboelectric charges for advanced TENG platforms.
研究领域:
材料科学
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纳米技术
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能源科学
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
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2025
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IF 5.5
Yixin Xu,Yiping Wang,Ying Li,Na Su,Shuozhen Hu,Xinsheng Zhang
Direct formic acid fuel cells (DFAFCs) are promising portable power sources with the advantages of easy handling and high theoretical open-circuit voltage. Exploring efficient Pd-based catalysts for formic acid oxidation (FAO) on the anode is important for the widespread use of DFAFCs. However, formic acid decomposition on the Pd surface restricts the FAO activity of the catalyst, in which the adsorbed hydrogen atoms combine together to form hydrogen molecules instead of generating H+ ions and transferring electrons at the interface. Herein, we report a polarization-induced electric field (PEF) strategy to facilitate FAO on Pd by directing interfacial charge transfer. Pd/TBT-X@SC catalysts with PEF are synthesized with tetragonal phase barium titanate (TBT) as the core, carbonized sucrose as the shell, and palladium nanoparticles as the active sites. The PEF strength is successfully regulated by varying the particle size of TBT. Stronger PEF and proper carbonized sucrose thickness facilitate the interfacial charge transfer on the Pd surface, thereby promoting the electrooxidation of adsorbed hydrogen to H+ ions and converting CO-like species to CO2. Moreover, PEF also induces the formation of electron-deficient Pd, thus reducing the bond strength between Pd and adsorbed intermediate species such as H and CO-like species. Consequently, FAO selectivity, activity, and anti-CO-like poisoning species property of Pd are enhanced by the introduction of PEF. Among all the catalysts, Pd/TBT-100 nm@SC exhibits the highest catalytic activity (7.49 mA·cm–2) and resistance to CO-like poisoning species. This work offers a new strategy for the design of catalysts with high FAO selectivity.
研究领域:
材料科学
·
电化学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
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