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141.
In order to broaden the application of potato pulp pectic polysaccharide (PPP) in stabilizing acidified milk drinks (AMDs) and investigate the stabilizing effect and physical properties of AMDs prepared with PPP, a comparative study was made among PPP, commercial high methoxyl pectin (HMP) and low methoxyl pectin (LMP). The zeta potential, rheology, particle size and serum separation of AMDs were evaluated after preparing with PPP, HMP and LMP, respectively. Results indicated that PPP led to lower serum separation than LMP (14.65% for AMDs prepared with 0.5% PPP compared to 25.05% for AMDs prepared with 0.5% LMP), but still higher than HMP (9.09% for AMDs prepared with 0.5% HMP). However, narrower particle size distribution and lower viscosity of AMDs was achieved by PPP than by LMP and HMP. PPP can electrostatically adsorb on the surface of casein and its abundant neutral sugar side chains would provide steric hindrance to prevent casein flocculation in AMDs. Our results might provide some new ideas for the application of PPP in improving the stability of AMDs.  相似文献   
142.
An improved drag force coefficient of gas-particle interaction based on the traditional Wen’s 1966 model is proposed. In this model, a two-stage continuous function is used to correct the discontinuous switch when porosity less than 0.2. Using this proposed correlation and the Wen’s 1966 model, a gas-particle kinetic energy and particle temperature model is developed to predict the hydrodynamic characteristics in backward-facing step gas-particle two-phase turbulent flows. Numerically results showed that they are in good agreement with experiment measurements and presented model are better due to a improvement of momentum transport between gas and particle phases. Particle dispersions take on the distinctively anisotropic behaviors at every directions and gas phase fluctuation velocity are about twice larger than particle phases. Particle phase has a unique transportation mechanism and completely different from the gas phase due to different density. Furthermore, the correlation values of axial–axial gas-particle are always greater than the radial–radial values at fully flow regions. The gas-particle two-phase interactions will make influence on two-phase turbulent flow behaviors.  相似文献   
143.
遥感干涉超光谱图像压缩编码   总被引:16,自引:11,他引:5  
基于卫星干涉超光谱成像光谱仪成像原理的分析,提出了一种新的遥感超光谱图像压缩方案,利用成像推扫平移特性提出一种低存储量,帧间小波域匹配的序列压缩,只需存储两帧图像,比起单帧处理提高图像PSNR 3-4dB.为了保护图像的光谱特征,系统采用了一种新的感兴趣区域(Region of interest, ROI) 编码技术,使系统的压缩比提高8倍以上.该感兴趣区域(ROI)编码采用率失真优化斜率提升,而不是比特平面移位,使图像在相同的光谱分辨率下拥有更好的空间分辨率.试验数据表明,算法大大保护了图像的光谱特性,在8倍压缩比情况时,满足卫星干涉超光谱遥感图像要求.  相似文献   
144.
Li  Xiangli  Zhao  Wenjuan 《Numerical Algorithms》2022,90(3):1017-1042
Numerical Algorithms - There are many conjugate gradient methods to solving unconstrained optimization problems. Compared with the conjugate gradient method, the accelerated conjugate gradient...  相似文献   
145.
Journal of Thermal Analysis and Calorimetry - A novel tri-substituted triazine in which substituted methacrylated piperzinyl (TMAPT) was synthesized and was then blended with di(acryloyloxy propyl)...  相似文献   
146.
2H MoS2 has been intensively studied because of its layer‐dependent electronic structures and novel physical properties. Though the metastable 1T MoS2 with a [MoS6] octahedron was observed over the microscopic area, the true crystal structure of 1T phase has not been strictly determined. Moreover, the true physical properties have not been demonstrated from experiments owing to the challenge for the preparation of pure 1T MoS2 crystals. 1T MoS2 single crystals were successfully synthesized and the crystal structure of 1T MoS2 re‐determined from single‐crystal X‐ray diffraction. 1T MoS2 crystallizes in the space group P m1 with a cell of a=b=3.190(3) Å and c=5.945(6) Å. The individual MoS2 layer consists of MoS6 octahedra sharing edges with each other. More surprisingly, the bulk 1T MoS2 crystals undergo a superconducting transition of Tc=4 K, which is the first observation of superconductivity in pure 1T MoS2 phase.  相似文献   
147.
Hydrogel formed by fluoroalkyl double-ended polyethylene glycol (Rf-PEG) micelles was studied to assess its properties to encapsulate a hydrophobic electron spin labeled drug, Chlorambucil–Tempol adduct (CT), and to control and sustain the drug release. The drug loaded hydrogel samples were characterized with variable-temperature dependent EPR experiment, and EPR theoretical lineshape analysis. It was found that CT molecules reside in the hydrophobic Rf-cores/IPDU shells of the Rf-PEG micelles and the maximum molecular-level loading capacity was estimated to be 18.8 mg per gram of the Rf-PEG. It has been known that Rf-PEG hydrogel with certain molecular masses for the fluoroalkyl group and the PEG chain shows properties of sol/gel phase coexistence and surface erosion, which represent the favorable condition for a pharmaceutical depot to control the kinetics of drug release. To evaluate the Rf-PEG’s biocompatibility and kinetics of the drug release, a cell proliferation assay was carried out on human oropharyngeal carcinoma (KB) cells. The results show that Rf-PEG is biocompatible and able to release CT to the cell media with a constant equilibrium concentration independent of the amount of CT loaded hydrogel.  相似文献   
148.
用柠檬酸络合法制备了钙钛矿型复合氧化物LaFeO3,并按不同比例进行掺杂,制备了La1-xPbxFeO3(x=0,0.1,0.3,0.5,0.7)。用XRD,SEM,IR,UV-vis等方法对其进行表征,其结构均为钙钛矿型。并测定了其对活性艳红X-3B水溶性染料脱色的光催化活性。实验结果表明:在A位掺杂Pb2 ,产生了较多氧空位,降低了光生电子与空穴的复合速率,使LaFeO3的光催化活性明显提高,其中La0.7Pb0.3FeO3效果最佳。  相似文献   
149.
The retention behavior of neutral, positively charged, and negatively charged solutes on the IAM.PC.DD2 stationary phase was investigated and compared. A set of monofunctional compounds and complex drugs (steroids, nonsteroidal anti‐inflammatory drugs, and β‐blockers) were selected for this study, i.e., neutral solutes and solutes with acidic or basic functionalities which are positively charged or negatively charged at pH 7.0. The correlation between the retention factor log kw at pH 7.0 on the IAM.PC.DD2 stationary phase and the partition coefficient log Poct or the distribution coefficient log D7.0 showed that the retention mechanism depends on the charge state and structural characteristics of the compounds. The neutrals were least retained on the IAM.PC.DD2 stationary phase, and positively charged solutes were more retained than negatively charged ones. This implies that the retention of the charged solutes is controlled not only by lipophilicity but also by the electrostatic interaction with the phospholipid, with which positively charged solutes interact more strongly than negatively charged ones.  相似文献   
150.
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