Materials
·
2022
·Vol. 15
·期 5
·1622
·
IF 3.748
Guonan Liu,Jilei Xu,Baojing Feng,Jinhui Liu,Dongqing Qi,Wenzhan Huang,Peixu Yang,Shaojun Zhang
Adjusting the microstructure through the deformation process is one of the ways to improve the properties of Mg alloys. Most studies have focused on the influence of the microstructure after deformation treatment on the mechanical properties of Mg alloys. In this paper, extruded and forged Mg-Gd-Y-Nd-Zr alloys were selected to investigate the corrosion performance of two deformed magnesium alloys immersed in 0.6 M NaCl solution using a hydrogen evolution test, a weight loss test, an immersion experiment, and an electrochemical test. The results showed that WE43 alloys undergoing different deformation treatments presented different microstructures, which led to different corrosion behaviors and corrosion resistance. The extruded WE43 alloy showed uniform corrosion, while the forged WE43 alloy suffered severe local galvanic corrosion. Meanwhile, the corrosion rate of the forged WE43 alloy was about four times faster than that of the extruded WE43 alloy.Keywords:magnesium;rare earth elements;erosion;weight loss;pitting corrosion
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Metals
·
2021
·Vol. 11
·期 5
·753
·
IF 2.351
Bianli Quan,Junqi Li,Chaoyi Chen
During Bayer alumina production with high-sulfur bauxite, the sulfide ions in the sodium aluminate solution caused serious corrosion to Q235 steel, which is the material of the tank equipment. This study investigates the effect of corrosion time on Q235 steel synergistic corrosion in sodium aluminate solution using the weight-loss method and electrochemical measurements. The results indicate that the corrosion rate decreases sharply, the rate equation satisfies the mathematical model of power function at the initial stage of corrosion, and the transformation of unstable iron sulfide to stable iron oxide at the later stage results in the decrease in sulfur content in the corrosion products and surface pseudo-passivation. There are two main types of corrosion products, as follows: one is the octahedral crystal particle, which is composed of Fe2O3, Fe3O4, Al2O3and NaFeO2, and the other is the interlayer corrosion between the surface layer and the matrix, which is composed of FeS, FeS2and MnS2. At day 3, the dynamics of the Q235 steel electrode is controlled by charge transfer and ion diffusion. However, at other times the dynamics are mainly controlled by charge transfer.Keywords:Q235 steel;sulfide;corrosion time;weight loss;electrochemistry;EIS;potentiodynamic polarization curve
研究领域:
材料科学
·
腐蚀工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2017
·
IF 4.529
Zhenna Zhang,Juan Wang,Xueying Zhang,Qingli Shi,Le Xin,Hongfei Fu,Yunyang Wang
This paper is focused on the effects of radio frequency (RF) heating on the relative activity of polyphenol oxidase (PPO), weight loss, texture, color, and microstructure of potatoes. The results showed that pure mushroom PPO was almost completely inactivated at 80 °C by RF heating. The relative activity of potato PPO reduced to less than 10% with increasing temperature (25–85 °C). Enzyme extract showed the lowest PPO relative activity at 85 °C after RF treatment, followed by the potato cuboids and mashed potato, about 0.19 ± 0.017%, 3.24 ± 0.19%, and 3.54 ± 0.04%, respectively. Circular dichroism analysis indicated that RF heating changed the secondary structure of PPO, as α-helix content decreased. Both electrode gap and temperature had significant effect ( P < .05) on weight loss, color, and texture of the potato cuboids. Microstructure analysis showed the changes of potato cell and starch during RF heating.
研究领域:
食品科学
·
食品工程
·
生物物理学
·
酶学
·
农产品加工
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Peng Wang,Ming Liu,Qichao Ran
Based on the weight loss and small molecule volatiles released during the thermal curing process of three kinds of benzoxazines , bisphenol A/aniline type benzoxazine (BA-a), p-cresol/diamine type benzoxazine (MPH-mda) and 2,4-xylenol/4,4′-methylenebis-(2,6-diisopropyl) aniline type benzoxazine (DMPH-mdpa), their curing mechanisms and the weight-loss mechanisms were studied. The weight-loss ratios and structure changes of these benzoxazines during the curing process were studied by weighing method, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The volatiles released from these benzoxazines during different curing stages were collected by a self-made experimental device. The structures of these volatiles were characterized by FTIR and proton nuclear magnetic resonance spectroscopy ( 1 H NMR). The results showed that the mixtures of imine , triazine , aniline and Schiff base were released from the cracking of the intermediate during the thermal curing of BA-a. Compared with BA-a, the weight loss of MPH-mda was smaller, and its volatile was a small amount of stable diamine type Schiff base. For DMPH-mdpa, because all active reaction points on benzene ring were occupied by alkyl groups , it cannot form effective polymer structures after ring-opening reactions, which led to that DMPH-mdpa had the most weight loss during the curing process, and mainly generated phenol type volatiles.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD PROTECTION
·
2018
·Vol. 81
·期 10
·1643-1650
·
IF 1.51
Huqing Yang,Xia Li,Guoquan Lu
Because of high water loss and rot observed in postharvest sweet potato ( Ipomoea batatas (L.) Lam.) roots, a carnauba wax (CW)–based nanoemulsion without or with glycerol monolaurate (CW-GML) was developed by a high-energy emulsification approach. The effects of the two coatings on decay, respiration rate, weight loss, surface color, total soluble sugar, and starch content as well as the sensory quality of sweet potato roots were investigated during storage at 20°C for 50 days. Compared with the control treatment (water) and CW coating alone, CW-GML coating exhibited higher emulsion stability and antifungal activity, and treatment resulted in a uniform and continuous coating on roots. The CW-GML and CW coatings both effectively reduced root weight loss and respiration rate and inhibited decay incidence compared with control roots during storage. The CW-GML coating showed markedly stronger inhibition of root rot than the CW coating. Both the CW-GML and CW coatings promoted an increase in root sweetness but did not negatively impact perceived flavor. The overall results demonstrate that the CW-GML coating holds great promise as an effective postharvest technology to preserve food quality and extend shelf life of sweet potato roots.
研究领域:
食品科学
·
采后生物学
·
农产品贮藏
·
食品保鲜技术
·
应用植物学
✓ 已验证
DOI
高影响因子
Life Sciences in Space Research
·
2022
·
IF 2.73
Fang Chen,Ning Jiang,Yi Wen Zhang,Meng Zhou Xie,Xin Min Liu
During the long-term orbital flight, exposure to microgravity negatively affects the astronauts' development of cognition, characterized by learning and memory decline. Gastrodia elata Blume (GEB) has a significant protective effect on cognitive impairment and has been used in Asia for centuries as a functional product. A previous study demonstrated that GEB could improve memory loss in mice caused by circadian rhythm disorders. However, the effects of GEB on cognitive dysfunction caused by weightless environments have not been investigated. In this study, mice received daily treatment with GEB (0.5, 1 g·kg −1 d −1 , i.g) and Huperzine A(Hup, 0.1 mg·kg −1 d −1 , i.g) orally until the end of the behavioral test (New object recognition test (NORT). Malondialdehyde (MDA) and nitric oxide (NO) levels were detected by kits, and expression of brain-derived neurotrophic factor (BDNF), protein kinase B (AKT), phosphorylated Akt (P-AKT), synaptophysin (SYN) and postsynaptic density 95(PSD95) in hippocampus were detected by western blotting . The results show that administration of GEB (0.5, 1 g·kg −1 d −1 , i.g) and Hup (0.1 mg·kg −1 d −1 , i.g) remarkably reverse HLS-induced learning and behavioral memory disorders, which were associated with significant changes in MDA and NO levels. Additionally, the protein expressions of BDNF, P-AKT/AKT, SYN, and PSD95 were significantly increased in the hippocampus. In summary, our findings will improve the reference for developing GEB as a functional product that improves memory decline.
研究领域:
神经科学
·
药理学
·
航天医学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2019
·
IF 3.78
Qun Liu,Haipeng Wang,Lei Chen,Wulong Li,Yakun Zong,Yi Sun,Zhanxiong Li
Fluorinated Poly(ε-caprolactone) (PCL) block copolymers PCL-PTFOA(2 h), PCL-PTFOA(4 h), PCL-PTFOA(6 h), PCL-PTFOA(8 h) were prepared via esterification by using poly(1H,1H,2H,2H-perfluorooctylacrylate) (PTFOA) with different molecular weights as reactants. It was found that PCL-PTFOA(6 h) and PCL-PTFOA(8 h) possessed the similar molecular weight via GPC analysis. PCL and fluorinated PCL block copolymers films were prepared by solution casting method. The structure and properties of film surface of the fluorinated PCL block copolymers were analyzed by energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM), Differential scanning calorimetry (DSC), water contact angles (WCAs) and the surface free energy. The results showed that the fluorinated PCL films possessed improved hydrophobicity because of the microphase separation between fluoropolymer chain and PCL chain. The enzymatic degradation of PCL, PCL-PTFOA(2 h), PCL-PTFOA(4 h) and PCL-PTFOA(6 h) films were performed at 37 °C in a phosphate buffer solution (PBS, 0.1 M, with a pH of 7.2–7.4) with lipase and analyzed by weight loss, SEM and EDS . It was found that the introduction of fluorine-containing segment reduced the rate of enzymatic degradation of the copolymer film in the early period, while increased the finally weight loss rate with a prolonged time. In addition, the enzymatic degradation rate of PCL-PTFOA(2 h) film and PCL-PTFOA(4 h) film was faster than that of PCL-PTFOA(6 h) film.
研究领域:
高分子科学
·
材料科学
·
生物降解
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2023
·Vol. 58
·期 7
·3538-3551
·
IF 3.3
Minghui Ge,Ruifeng Ying,Meigui Huang
Summary Post-harvest apricot fruits are susceptible to moisture loss and disease leading to quality deterioration. Herein, we identified that the cell wall of the wheat grain regulated the hydration properties of grains. Arabinoxylan/β-glucan/ferulic acid/cellulose (ABF-C) composite films simulating the cell wall of the wheat aleurone layer were prepared and showed excellent thermodynamic properties and hydration properties. Meanwhile, the decay percentage, weight loss percentage and respiration intensity of apricot fruits at 35 days of storage were greatly decreased by 23.5%, 23.93% and 39.95%, respectively, and the shelf life of apricot fruits was extended by 7 days after the coating ABF-8%C composite film treatment. The ABF-C composite films effectively prevented the dissipation of moisture of high mobility in apricot fruits during storage. We provide new insight into moisture regulation mechanism of edible films simulating cell wall structure on post-harvest fruits.
研究领域:
食品科学
·
农业工程
·
植物生理学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2013
·
IF 0.807
Jiaojiao Shang,Guo Yao,Shaojian Lin,Jianwu Lan,Xia Huang,Wen He
A series of thermoplastic poly(ester-imide-ether) (PEIE) elastomers, with different ratios of soft/hard segment 85/15, 80/20 and 70/30, were prepared from 1, 4-butanediol (BD), poly(tetramethylene glycol) (PTMG) and imide dicarboxylic acid monomer based on 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) and glycine (GLY). The chemical structures of the imide dicarboxylic acid and PEIEs were characterized by FT-IR and 1H-NMR, respectively. The intrinsic viscosities, thermal properties and mechanical properties of these PEIEs were investigated. The results show that introduction of imide group endows the PEIEs with excellent thermal stability, the melting point of PEIEs at about 220°C, and the temperature of 5% weight loss appears at the range of 332–358°C. In addition, the mechanical properties of PEIEs are also improved with the increment of imide units, the maximum stress and strain reached to 17.15 MP and 1043.75%, respectively.
研究领域:
高分子化学
·
材料科学
·
热分析
·
机械工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 44
·23191-23201
·
IF 3.708
Gang Zhang,Shu-shan Yuan,Zhi-min Li,Sheng-ru Long,Jie Yang
Two kinds of high glass temperature poly(arylene ether sulfone)s containing thioether and biphenyl units (PASSs) have been developed. The polymers were prepared by a polycondensation reaction of 4,4′-bis(4-chlorophenylsulfone)biphenyl (BCPSB) and 4,4′-dimercaptodiphenyl sulfone (DMDPS) (or 4,4′-bis(4-mercaptophenylsulfone)biphenyl (BMPSB)). They showed good thermal properties such as a relatively high glass transition temperature of 263–282 °C and a 5% weight-loss temperature (T5%) of 441–445 °C. The water flux and retention rate of the resultant membranes were 0.61–2.48 L m−2 h−1 and 89.47–94.91%, respectively. Interestingly, we found that the corrosion resistance of the membranes had been largely improved with the oxidization treatment. They were even insoluble in NMP, DMSO, concentrated H2SO4, aqua regia and so on, while the polymers without oxidation were soluble or destroyed in above solvents. In addition, we found the water flux of the oxidized membrane was also improved but the retention rate only decreased a little.
研究领域:
材料科学
·
高分子化学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Agriculture and Food Research
·
2022
·
IF 0
Xiaohong Guo,Qianting Liu,Jiaming Du,Yidan Guo,Zhenlei Xiao,Liping Kou
Logistics transportation is the critical procedure that sprouts must go through from producers to consumers, but during this transportation, it is very easy to cause quality deterioration. Generally, the quality of fresh peanut sprouts during cold chain transportation is maintained by using the high polymer phase change cold storage agent (CSA). In this research, different quantities of CSA were used to maintain peanut sprouts quality，and the effects of CSA on sprouts quality under simulated transportation conditions were investigated for 5 days, including overall quality, water content, ascorbic acid content, total phenolic and total flavonoid contents, malondialdehyde (MDA) content, weight loss rate, along with the activities of superoxide dismutase (SOD) and catalase (CAT). According to the overall quality, it is meaningful to observe the changes of each index within 3 days. Results indicated that 4 bags of CSA could decrease the temperature to 8.4 °C within 580 min and keep rising slowly until the maximum temperature reached 18.9 °C at 4260 min. In addition, it effectively prevented the loss of water (93.87%) and ascorbic acid (5.38 mg/100 g), as well as inhibited the production of MDA, which was attributed to a slow metabolism in low temperatures. Moreover, the 4 bags of CSA had no negative effects on the contents of total phenolic and flavonoid along with CAT activity of peanut sprouts, and the sensory quality was maintained at an optimum level. In conclusion, it had a positive effect on the maintenance of quality during transportation when the mass ratio of sprouts to CSA was 15:8 and the volume ratio of styrofoam container and CSA was 10:1.
研究领域:
食品科学
·
采后技术
·
物流与运输
✓ 已验证
产品关联
DOI
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Hongyu Cen,Jiaojiao Cao,Zhenyu Chen,Xingpeng Guo
The corrosion inhibition performance of 2-mercaptobenzothiazole (MBTH) for carbon steel in a CO 2 -H 2 O system was investigated by weight loss, surface analysis, electrochemical measurements, and quantum chemical calculations. Results showed that MBTH could effectively protect carbon steel from CO 2 corrosion and inhibition efficiency of MBTH in supercritical CO 2 was higher than that in non-supercritical CO 2 situation. The differential capacitance curves revealed that excess positive charges would be on the surface of carbon steel in the supercritical-CO 2 system while negative charges accumulated on carbon steel surface in non-supercritical CO 2 condition. The adsorption model was proposed to explain the inhibition mechanism of MBTH.
研究领域:
腐蚀科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）