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Xiao-Mei Sha Li-Jun Zhang Wen-Mei Chen Guang-Yao Wang Jin-Lin Li Zi-Zi Hu Zong-Cai Tu 《International Journal of Food Science & Technology》2022,57(3):1573-1586
Thermal action in extraction process had effects on characteristic tryptic peptides identification and gelling properties of porcine gelatin. SDS-PAGE, HPLC-LTQ/Orbitrap high-resolution mass spectrometry, texture analyser and rheometer were used to evaluate collagen depolymerisation degree, characteristic tryptic peptides and gelling properties of gelatins prepared in various thermal actions. Results showed that with increasing temperature and time, depolymerisation degree enlarged, while gel strength, gelling and melting temperature decreased. Mass spectra showed that 47 and 49 common characteristic tryptic peptides were identified in gelatins extracted at 50 °C and 100 °C with various times, respectively. Moreover, 34 common characteristic tryptic peptides were identified in all gelatin samples. Further comparison between this work and our previous investigations yielded 20 common characteristic tryptic peptides, which stably exist in various thermal actions. These common characteristic tryptic peptides may be very helpful for the accurate authentication of porcine gelatin. 相似文献
3.
In the present paper, therapeutic treatment of infected tumorous cells has been studied through mathematical modeling and simulation of heat transfer in tissues by using a nonlinear dual-phase lag bioheat transfer model with Dirichlet boundary condition. The components of volumetric heat source in this model such as blood perfusion and metabolism are assumed experimentally validated temperature-dependent function, which gives more accurate temperature distribution in tissues through this model. We have used the finite difference and RK (4, 5) techniques of numerical methods to solve the proposed problem and obtained the exact solution in a particular case. After comparison, we got a good agreement between them. We have used dimensionless quantities throughout this paper. The effect of relaxation and thermalization time with respect to dimensionless temperature distribution has been analyzed in the treatment process. 相似文献
4.
《Ceramics International》2022,48(20):29862-29872
Thermal shock parameters (R, R''', R'''' and Rst) of MgAlON–MgO composites obtained with additions of spent MgO–C brick were calculated using measured mechanical properties and thermal expansion coefficient, determining their resistance to fracture initiation and crack propagation. The cyclic thermal shock experiments of MgAlON–MgO composites performed from 1398 K to ambient temperature indicate that as number of thermal shock cycle increases, retained strength ratio of MgAlON and MgAlON–4.2 wt%MgO sharply decrease and then keep constant, while that of MgAlON–10.5 wt%MgO and MgAlON–15.7 wt%MgO slowly decrease. The reason for the difference is that MgAlON and MgAlON–4.2 wt%MgO show low value of R''' and R'''', and high value of R and Rst. Moreover, precipitation of impurity containing Fe may play a positive role in improvement of thermal shock resistance of MgAlON–MgO composites. MgAlON?4.2 wt%MgO has the maximum retained strength (55 MPa) even after 5 thermal shock cycles, which is expected to be used in the metallurgical industry. 相似文献
5.
《Ceramics International》2022,48(4):5091-5099
The impact of the addition of TiO2 nanoparticles and nanowires on the morphology, phase characteristics, contact angle, and electrochemical performance of chemically bonded phosphate ceramic coatings (CBPCs) was investigated. The chemical composition and surface morphology of the TiO2 nanoparticle and nanowire modified with and without (heptadecafluoro-1,1,2,2-tetradecyl) trimethoxysilane were characterized. Results indicated that the hydrophobic –CF2– and –CF3 groups were successfully introduced into the TiO2 nanoparticles and nanowires after modification. Corrosion resistance of CBPCs with TiO2 was evidently improved compared with that without TiO2. Such improvement was mainly due to the combined effects of low surface energy materials and micro/nano structures. In addition, CBPCs with TiO2 nanowires exhibited higher hydrophobicity and corrosion resistance than those with TiO2 nanoparticles because of the special columnar structure of the nanowires. 相似文献
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7.
《International Journal of Hydrogen Energy》2022,47(36):16165-16178
This study deals with the manufacturing of catalyst-coated membranes (CCMs) for newcomers in the field of coating. Although there are many studies on electrode ink composition for improving the performance of proton-exchange membrane fuel cells (PEMFCs), there are few papers dealing with electrode coating itself. Usually, it is a know-how that often remains secret and constitutes the added value of scientific teams or the business of industrialists. In this paper, we identify and clarify the role of key parameters to improve coating quality and also to correlate coating quality with fuel cell performance via polarization curves and electrochemical active surface area measurements. We found that the coating configurations can affect the performance of lab-made CCMs in PEMFCs. After the repeatability of the performance obtained by our coating method has been proved, we show that: (i) edge effects, due to mask shadowing - cannot be neglected when the active surface area is low, (ii) a heterogeneous thickness electrode produces performance lower than a homogeneous thickness electrode, and (iii) the origin and storage of platinum on carbon powders are a very important source of variability in the obtained results. 相似文献
8.
《Ceramics International》2022,48(5):6302-6312
In this study we synthesized Li-rich Li1.2Ni0.13Mn0.54Co0.13O2 (LMNCO) as a composite cathode material through a two-step spray-drying method, using transition metal (TM) acetates and citric acid (CA, as a chelating agent) at various molar ratios and then calcining at various temperatures for various periods of time. This two-step spray-drying method created hierarchical nano/micro-sphere structures of the LMNCO cathode material. The LMNCO cathode exhibited the best electrochemical performance when synthesized with a TM:CA ratio of 3:2, a calcination temperature of 900 °C, and a calcination time of 5 h. This as-prepared LMNCO composite was then modified with polyimide (PI) at various weight ratios (PI/LMNCO = 0.5, 1.0, and 1.5 wt%) to improve its electrochemical properties. Among the various structures, the LMNCO cathode material coated with 1.0 wt% of PI at a layer thickness of approximately 1.88 nm achieved the best initial discharge capacities. This modified electrode also displayed enhanced cycle stability, with over 93.3 and 87.9% of the capacity retained after 30 cycles at 0.1C and 100 cycles at 1C, respectively. In comparison, the capacity retention of the unmodified LMNCO electrode measured under the same conditions was no more than 91.3% at 0.1C and 70.1% at 1C. Thus, surface modification with PI was an effective method for improving the coulombic efficiency, discharge capacity, and long-term cycling performance of the LMNCO cathode. Such PI-coated LMNCO composite cathode materials appear to be potential candidates for use in next-generation high-performance lithium-ion batteries. 相似文献
9.
《Advanced Powder Technology》2022,33(11):103817
The heat production and thermal storage characteristics of rapid-preparation amorphous powder activated coke (RAC) were investigated. RAC was prepared by using a drop-tube reactor system. The natural oxidation characteristics of RAC were studied through combined TG–FTIR analysis and temperature-programmed experiment. Experimental results showed that CO and CO2 were the main oxidation products of RAC in air, and that the oxidation reaction was in accordance with the Arrhenius equation and law of mass action. Thermal storage characteristics were studied through computational fluid dynamics simulation. The maximum excess temperature θmax increases linearly with the increase of the initial temperature. The concentration fields of the products show that CO2 is mainly concentrated in the upper part of the coke bin, and the CO generated by CO2 at high temperature is mainly concentrated in the central part of the coke bin. 相似文献
10.
《International Journal of Hydrogen Energy》2022,47(80):34244-34256
A conducting and anticorrosive coating is crucial for the application of metal bipolar plates (BP) in proton exchange membrane fuel cell (PEMFC). In this work, a Ti3C2Tx (T)-carbon black (C)-acrylic epoxy (AE) coating is prepared on 304 stainless steel (SS) with enhanced corrosion resistance and conductivity. The corrosion resistance of the T-C-AE coating is investigated in a 0.5 M H2SO4 solution as compared to the AE, T, and T-AE coatings. The T-C-AE coated 304SS exhibits the strongest corrosion resistance with the most positive corrosion potential and the lowest corrosion current density of 0.00673 μA cm?2 in all the samples, while retaining intact and compact surface morphology with the lowest metal ion dissolution even after immersed for 720 h. The addition of Ti3C2Tx and carbon black into the AE matrix greatly decreases interfacial contact resistance (ICR), and the T-C-AE coating achieves a low ICR of 15.5 mΩ cm?2 under 140 N cm?2 compaction force. The excellent anticorrosion performance is mainly attributed to the physical barrier and the cathodic protection provided by the stacked Ti3C2Tx (MXene) nanosheets in the T-C-AE coating. This eco-friendly, conducting, and anticorrosive T-C-AE coating has a good application prospect on SS BP of PEMFC. 相似文献