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排序方式: 共有892条查询结果,搜索用时 31 毫秒
1.
Chunyan Xu Ying Wang Daodong Pan Changyu Zhou Jun He Jinxuan Cao 《International Journal of Food Science & Technology》2021,56(4):1690-1702
To investigate the effect of cooking temperature (55, 65, 75, 85 and 95 °C) on texture and flavour binding of braised sauce porcine skin (BSPS), sensory acceptance, microstructure and flavour-binding capacity were investigated during the processing of BSPS. Samples cooked at 85 and 95 °C showed better texture and aroma scores. Hardness and chewiness of BSPS were obviously improved at 85 and 95 °C than control group. Collagen structure was significantly destroyed over 85 °C. The porcine skin collagen heated at 85 and 95 °C showed relatively higher flavour-binding capacity than other samples. The improvement of texture of BSPS was mainly attributed to the degradation of collagen. Higher aroma scores of BSPS were related to intense binding abilities with aroma compounds at 85 and 95 °C. Cooking at 85 or 95 °C could be an optimal cooking temperature for BSPS. 相似文献
2.
To improve the hydrophobicity of bagasse hemicellulose-based films, glutaraldehyde was applied when preparing films of original and cationic bagasse hemicellulose with the addition of polyvinyl alcohol and sorbitol. The results showed that the cationic modification could increase the hydrophobicity of the hemicellulose-based film, and the hydrophobicity of hemicellulose-based films crosslinked with glutaraldehyde also increased. However, cationic modification of hemicellulose decreased the stress of the hemicellulose-based film. While crosslinking with glutaraldehyde increased the stress of both the original and cationic hemicellulose-based films. Macrophotography indicated that the film formability of the original hemicellulose was better than that of cationic hemicellulose. Through SEM observation, the degree of bonding of different components of the films was found to be increased due to crosslinking with glutaraldehyde. The crosslinking reaction between glutaraldehyde and hemicellulose was further confirmed by FT-IR spectroscopy. 相似文献
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为实现超疏水织物的绿色加工,采用正硅酸乙酯(TEOS)为前驱体,乙醇和水为溶剂制备硅溶胶预缩体对棉织物进行疏水整理,研究各工艺因素对棉织物疏水性能的影响,重点分析预缩体的制备、硅烷偶联剂的添加、低温烘干工艺与提高整理织物疏水性的相关性。结果表明:棉织物表面的SiO2纳米粒子形成的粗糙表面与织物表面结合的疏水脂肪烃链可赋予织物良好的疏水性;在TEOS量为0.1 mol,乙醇量为0.9 mol,水的量为0.8 mol,先二浸二轧硅溶胶,再浸轧十六烷基三甲氧基硅烷醇溶剂优化工艺条件下,整理棉织物的水接触角可达152.1°,棉织物的力学性能得到提高。 相似文献
5.
以纳米ZnO、甲基丙烯酸十二氟庚酯(DFMA)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为原料,用半连续种子乳液聚合法制备纳米ZnO/有机氟改性聚丙烯酸酯,探索了合成工艺,然后将合成乳液用于亚麻织物的整理。采用FT-IR、XPS和SEM等方法对乳胶膜和整理后的织物进行表征分析。结果表明:当乳化剂质量分数为4%,引发剂质量分数为1.5%,反应温度为80℃,保温时间为60 min时,乳液的合成效果最好。合成的乳液具有良好的抗紫外性能,其乳胶膜的吸水率为8.64%。XPS和SEM测试结果显示,合成的复合乳液和织物相结合,提高了亚麻织物的疏水性。相比聚丙烯酸酯整理后的织物,经复合乳液整理后的亚麻织物对水的接触角提高了60.4°。 相似文献
6.
Bo Zhong Jinze Zhang Hanqun Wang Long Xia Chunyu Wang Xiaodong Zhang Xiaoxiao Huang Guangwu Wen 《International Journal of Applied Ceramic Technology》2020,17(6):2598-2611
Novel SiC-based nanomaterials, namely the nitrogen and aluminum co-doped SiC@SiO2 core-shell nanowires and nitrogen-doped SiO2/Al2O3 nanoparticles, have been fabricated through a facile thermal treatment process based on the chemical vapor deposition and vapor-liquid reaction. These nanomaterials show remarkable hydrophobicity with a water contact angle (CA) over 140°, which are aroused by the surface zigzag morphology of the nanostructures and the hydrocarbyl groups generated during the preparation process. Moreover the nanocomposites also exhibit relatively prominent microwave absorption (MA) properties in the frequency range of 2.0-18.0 GHz. The minimum reflection loss (RL) value as low as −23.68 dB can be observed at 14.16 GHz when the absorber thickness is 2.6 mm with a loading rate of 16.7 wt%. And the nanocomposites-based absorbent can achieve an effective absorption bandwidth (RL < −10 dB) of 4.48 GHz with the absorbent thickness of 2.5 mm. This enhanced microwave attenuation performance can be attributed to multiple polarizations and perfect impedance matching conditions, as well as multiple internal reflections. These marvelous properties make these N and Al co-doped SiC@SiO2 core-shell nanowires and N-doped SiO2/Al2O3 nanoparticles display extensive application potential as MA materials in harsh environment. 相似文献
7.
Nicki Frederiksen Assoc. Prof. Paul R. Hansen Dr. Dorota Zabicka Magdalena Tomczak Malgorzata Urbas Dr. Ilona Domraceva Prof. Fredrik Björkling Assoc. Prof. Henrik Franzyk 《ChemMedChem》2020,15(24):2544-2561
The influence of hydrophobicity on antibacterial activity versus the effect on the viability of mammalian cells for peptide/peptoid hybrids was examined for oligomers based on the cationic Lys-like peptoid residue combined with each of 28 hydrophobic amino acids in an alternating sequence. Their relative hydrophobicity was correlated to activity against both Gram-negative and Gram-positive species, human red blood cells, and HepG2 cells. This identified hydrophobic side chains that confer potent antibacterial activity (e. g., MICs of 2–8 μg/mL against E. coli) and low toxicity toward mammalian cells (<10 % hemolysis at 400 μg/mL and IC50>800 μg/mL for HepG2 viability). Most peptidomimetics retained activity against drug-resistant strains. These findings corroborate the hypothesis that for related peptidomimetics two hydrophobicity thresholds may be identified: i) it should exceed a certain level in order to confer antibacterial activity, and ii) there is an upper limit, beyond which cell selectivity is lost. It is envisioned that once identified for a given subclass of peptide-like antibacterials such thresholds can guide further optimisation. 相似文献
8.
Facile Fabrication of Cellulosic Paper-based Composites with Temperature-controlled Hydrophobicity and Excellent Mechanical Strength 下载免费PDF全文
In this paper,we presented a novel strategy to employ a plantderived carbohydrate polymer,i.e.,cellulose,to prepare a hydrophobic composite.Cellulose was used as a scaffold,and ethylene-propylene side by side(ES)fiber was thermally melted and then coated on the cellulose surface to achieve hydrophobicity.Experimental results revealed that the thermocoating ES fibers greatly increased the water contact angle of the cellulose scaffold from 25°to 153°while simultaneously enhanced the wet tensile strength of the composite approximately 6.7-fold(drying temperature of 170℃)compared with the pure cellulose paper.In particular,compared with other related research,the prepared cellulose-based composite possessed excellent hydrophobicity and superior mechanical strength,which introduces a new chemical engineering approach to prepare hydrophobic cellulose-based functional materials. 相似文献
9.
Jing Li Yuhua Yin Yaseen Muhammad Jing Yang Song Yang Hongquan Yang Maria Sahibzada 《Polymer International》2019,68(6):1091-1101
In this study, a new modifier (KPG) was prepared by modifying graphene oxide with γ‐glycidoxypropyl trimethoxysilane (KH560) and polydimethylsiloxane (PDMS). KPG was in turn added to aqueous urethane acrylate for the fabrication of waterborne polyurethane polyacrylate emulsion modified with KH560‐PDMS composite (KPG/WPUA). Textural characterizations of the KPG/WPUA coating were achieved via Fourier transform infrared, SEM, TGA and AFM techniques, which revealed that the KPG/WPUA film possessed a smooth surface. The synthesized KPG/WPUA films were tested for mechanical properties, hydrophobicity and acid/water corrosion performance which suggested their highly hydrophobic surface. KPG/WPUA with 0.1% KPG showed a contact angle of 118.35°, 30.35° higher than that of pristine WPUA. The KPG/WPUA film exhibited higher thermal stability, i.e. a 5% weight loss temperature of 305 °C, which was 30 °C higher than that of pristine WPUA film. The Young's modulus and elongation at break of the KPG/WPUA film were 34.1 MPa and 74.88% respectively, which were higher than that of WPUA film. Furthermore, KPG/WPUA films exhibited greater resistance (without obvious blistering and the white spotting phenomenon) to H2O2, HCl and water corrosion than pristine WPUA. The superior performance of KPG/WPUA films was attributed to the network chain structure formed upon the introduction of KPG into WPUA. The outstanding performance of KPG/WPUA films in terms of mechanical properties, thermal stability and high resistance to acidic and water corrosion makes them interesting alternative contenders for target applications. © 2019 Society of Chemical Industry 相似文献
10.
Changes of the cell surface hydrophobicity of Lactobacillus acidophilus La‐5 in response to pH,temperature and inulin 下载免费PDF全文
Antonio Bevilacqua Leonardo Petruzzi Barbara Speranza Daniela Campaniello Milena Sinigaglia Maria Rosaria Corbo 《International Journal of Food Science & Technology》2018,53(5):1262-1268
The main topic of this study was to study how cell surface hydrophobicity (CSH) could change in response to pH, temperature and inulin; Lactobacillus acidophilus La‐5 was used as a model microorganism. pH, temperature, inulin and incubation time (exposure to prebiotic or incubation at pH 4.0 and 9.0) were combined through a full factorial design and a Central Composite Design; the results were analysed using a multifactorial anova (first step) and a stepwise regression (second step). Temperature and pH significantly affected CSH: an increase in the temperature determined a significant increase in CSH, whereas the correlation pH vs. CSH was negative, as an increase in pH caused a significant decrease in CSH. Inulin played a significant role, but its effect could be influenced by temperature, pH and exposure time. This study is the first approach on the effects of some environmental factors on CSH and suggests that the culturing conditions and/or the exposure to some prebiotics could modify it with positive or negative effects. 相似文献