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1.
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.
测算了由二(2-乙基己基)磷酸钠,金属盐(CoSO4,NiSO4,ZnSO4,MgCl2或Cr(NO3)3)水溶液,正辛醇和正辛烷组成的微乳液中正辛醇从连续油相到界面的ΔGo→i^o和水的极限增容量φ'H2O。用金属萃取络合物反胶束的形成及其亲油性解释了金属离子对φ'H2O和ΔGo→i^o的影响。  相似文献   
3.
The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity.  相似文献   
4.
氟化活性炭纤维对极性分子的吸附   总被引:3,自引:0,他引:3  
将活性炭纤维(ACF)与氟气反应制备出氟化活性炭纤维(FACF),根据将FACF与参照试样XPS的对比,碳原子是以sp^3杂化轨道同氟原子形成共健键。αs图分析氮吸附等温线的线果表明,ACF氟化后其比表面积和微孔容积都显著降低,微孔宽度基本不变,ACF的水吸附等温线呈V型,而FACF对水的吸附量极小;FACF的微孔表面具有完美的憎水性和高稳定性,乙醇和甲醇在ACF上的吸附等温线是Ⅰ型,在FACF上接近于Ⅰ型,但吸附量显著降低。  相似文献   
5.
Cytokinins are a class of phytohormones, signalling molecules specific to plants. They act as regulators of diverse physiological processes in complex signalling pathways. It is necessary for plants to continuously regulate cytokinin distribution among different organs, tissues, cells, and compartments. Such regulatory mechanisms include cytokinin biosynthesis, metabolic conversions and degradation, as well as cytokinin membrane transport. In our review, we aim to provide a thorough picture of the latter. We begin by summarizing cytokinin structures and physicochemical properties. Then, we revise the elementary thermodynamic and kinetic aspects of cytokinin membrane transport. Next, we review which membrane-bound carrier proteins and protein families recognize cytokinins as their substrates. Namely, we discuss the families of “equilibrative nucleoside transporters” and “purine permeases”, which translocate diverse purine-related compounds, and proteins AtPUP14, AtABCG14, AtAZG1, and AtAZG2, which are specific to cytokinins. We also address long-distance cytokinin transport. Putting all these pieces together, we finally discuss cytokinin distribution as a net result of these processes, diverse in their physicochemical nature but acting together to promote plant fitness.  相似文献   
6.
Protein solubility is based on the compatibility of the specific protein surface with the polar aquatic environment. The exposure of polar residues to the protein surface promotes the protein’s solubility in the polar environment. The aquatic environment also influences the folding process by favoring the centralization of hydrophobic residues with the simultaneous exposure to polar residues. The degree of compatibility of the residue distribution, with the model of the concentration of hydrophobic residues in the center of the molecule, with the simultaneous exposure of polar residues is determined by the sequence of amino acids in the chain. The fuzzy oil drop model enables the quantification of the degree of compatibility of the hydrophobicity distribution observed in the protein to a form fully consistent with the Gaussian 3D function, which expresses an idealized distribution that meets the preferences of the polar water environment. The varied degrees of compatibility of the distribution observed with the idealized one allow the prediction of preferences to interactions with molecules of different polarity, including water molecules in particular. This paper analyzes a set of proteins with different levels of hydrophobicity distribution in the context of the solubility of a given protein and the possibility of complex formation.  相似文献   
7.
硅橡胶复合绝缘子因其优异的憎水性及憎水迁移性而具备较好的防污闪能力,往往作为应对污闪事故的首选方案。但在部分特殊工业粉尘地区,复合绝缘子在短时间运行后会出现爬电及蚀损现象,并发展为绝缘失效。为研究特殊工业粉尘地区复合绝缘子的腐蚀失效过程,测试了某特殊工业园区内运行的复合绝缘子的表面污秽度及污秽成分、污闪电压梯度、憎水性能及微观性能,并分析了其腐蚀失效过程。主要结论如下:绝缘子表面等值盐密为0.1~0.2 mg/cm2,其污秽成分与化工污源类似;存在自然污秽时绝缘子表面憎水性良好,但其憎水性的减弱、恢复及迁移特性均不能满足运行要求;绝缘失效的起因是电晕放电导致憎水性降低,进而导致伞裙电蚀损,最后发展为绝缘失效。  相似文献   
8.
憎水性等级(Hydrophobicity Class,HC)是衡量绝缘子性能的重要指标之一。在实际环境的多种因素作用下绝缘子伞裙表面存在局部憎水性差异,为了准确识别绝缘子的性能,本文提出了一种基于深度学习的局部自适应绝缘子检测与憎水性分类模型。首先,通过绝缘子分割模块分离绝缘子与背景区域,为后续针对绝缘子区域的操作提供分割信息;然后将绝缘子区域划分为固定大小的图像块,在缩小分辨率减小运算难度的同时保留了绝缘子表面的细节信息;最后通过憎水性分类模块分析图像块内绝缘子的憎水性。实验使用巡检维护现场的绝缘子图片作为样本集,分阶段构建模型,分别对分割阶段和憎水性分类阶段的准确性进行评估。实验结果显示分割阶段模块能有效识别绝缘子和背景区域,交叉验证的测试集准确率均大于97.21%,并且憎水性分类阶段模块能准确分析绝缘子憎水性,对140幅测试图片的识别准确率达到98.65%。经过实验证明本文提出的模型在复杂自然环境中检测绝缘子性能是一种有效的解决方案。  相似文献   
9.
研究了双组分室温固化型低表面能氟涂层的配合技术,所用材料的物化特性;讨论了基料、填料、助剂等对氟涂料的影响机理。实验结果表明:氟涂层的表面能为10.6 mJ/m2,疏水角可达到122°,附着力为1级、硬度为4H,同时涂层具有耐腐蚀和耐化学性等性质。  相似文献   
10.
The experimental results on the effect of adding trimethylethoxysilane (TMES) as a co-precursor on the hydrophobicity and physical properties of tetraethoxysilane (TEOS) based silica aerogels, are reported. The molar ratio of TEOS, ethanol (EtOH), water (0.001 M oxalic acid catalyst) was kept constant at 1:5:7 respectively, while the molar ratio of TMES/TEOS (A) was varied from 0 to 0.6. It has been observed that as the A value increases, the gelation time increases. The hydrophobicity was tested by measuring the contact angle, and the surface chemical modification was confirmed by the FTIR spectroscopy studies. The thermal stability of the hydrophobic aerogels was studied in the temperature range from 25 to 800°C. The hydrophobic nature of the aerogel could be maintained up to a temperature of 287°C and above this temperature the aerogels become hydrophilic. The bulk density and the optical transmittance of the aerogels have been found to decrease with increase in A value. The aerogels have been characterized by Fourier transform infrared spectroscopy (FTIR), Optical transmittance, Scanning electron microscopy (SEM), Differential thermal analysis (DTA) and Thermogravimetric analysis (TGA), and Contact angle measurements.  相似文献   
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