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排序方式: 共有199条查询结果,搜索用时 15 毫秒
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Erfan Danesh Mostafa Goudarzi Hossein Jooyandeh 《Sensing and Instrumentation for Food Quality and Safety》2018,12(4):2416-2425
The effects of transglutaminase treatment (0–2 units/g milk protein) on the chemical composition, textural characteristics, proteolysis and yield of reduced-fat Iranian white cheese (milk fat: 0.4–1.4% w/w) incorporated with whey proteins (0–6 g/L milk) were investigated. Enzyme-mediated inclusion of whey proteins in the reduced-fat cheese caused a noticeable increase in moisture to protein (M:P) ratio with concomitant decease in the hardness rheological parameters of fracture stress and Young’s and storage (G’) moduli. However, increase in concentrations of whey proteins or/and transglutaminase enzyme above a critical level led to formation of a cheese matrix with lower moisture content and greater values of hardness indices. Whey protein addition and transglutaminase treatment resulted in the same trends of changes in proteolysis rate and cheese yield as in cheese softness. Response surface method (RSM) suggested that the enzymatic incorporation of 4.2 g deliberately added whey proteins to 1 L of milk (1.04% w/w fat) into the cheese matrix using 0.833 unit transglutaminase per gram milk protein would provide a reduced-fat product with the softest texture and the highest yield. The scanning electron micrographs showed formation of honeycomb structures in the protein matrix of the reduced-fat sample with optimum formulation. 相似文献
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Fengjiao Zhang Erfan Mohammadi Ge Qu Xiaojuan Dai Ying Diao 《Advanced materials (Deerfield Beach, Fla.)》2020,32(39):2002823
Molecular orientation plays a critical role in controlling carrier transport in organic semiconductors (OSCs). However, this aspect has not been explored for surface doping of OSC thin films. The challenge lies in lack of methods to precisely modulate relative molecular orientation between the dopant and the OSC host. Here, the impact of molecular orientation on dopant–host electronic interactions by large modulation of conjugated polymer orientation via solution coating is reported. Combining synchrotron-radiation X-ray measurements with spectroscopic and electrical characterizations, a quantitative correlation between doping-enhanced charge carrier mobility and the Herman's orientation parameter is presented. This direct correlation can be attributed to enhanced charge-transfer interactions at host/dopant interface with increasing face-on orientation of the polymer. These results demonstrate that the surface doping effect can be fundamentally manipulated by controlling the molecular orientation of the OSC layer, enabling optimization of carrier transport. 相似文献
56.
Mohammad Sabet Hasan Jahangiri Erfan Ghashghaei 《Journal of Materials Science: Materials in Electronics》2018,29(13):10853-10863
In this experimental work, different conductive polymer nanocomposites were synthesized using polypyrrole as conductive polymer and CoFe2O4, NiFe2O4, CNT and graphene as fillers. X-ray diffraction pattern was used to study the crystallinity of the products and it was found CoFe2O4, NiFe2O4, CNT, and graphene were successfully embedded in the polymer matrix. To further approve the synthesis of the nanocomposites, energy dispersive X-ray spectroscopy was served. Surface groups of the synthesized nanocomposites were studied by Fourier transform infrared and Raman spectroscopy. The morphology of the products was examined by scanning electron microscopy and transmission electron microscopy. It was found the fillers were successfully embedded in the polymer matrix and they were in nanometer scales. To investigate the magnetic properties and conductivity of the polymer nanocomposites, alternating gradient force magnetometer and four-point probe were used, respectively. Finally, the microwave absorption properties of the polymer nanocomposites were studied and it was found the fillers have different effects on the polymer microwave absorption value. 相似文献
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以偶氮二异丁腈(AIBN)为引发剂,甲苯为溶剂,甲基丙烯酸甲酯(MMA)与丙烯酸(AA)经溶液聚合制得共聚物.差热分析(DTA)结果表明,在共聚物用量10mg,参比物αAl2O38mg,升温速度5℃/min,仪器灵敏度±10μV,走纸速度4mm/min的条件下,DTA曲线上可明显观察到共聚物的Tg,且共聚物玻璃化温度(Tg)随AA含量增加而升高,当AA含量为11%时,共聚物玻璃化温度(Tg)达147℃ 相似文献
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Piecewise constant level set method for structural topology optimization with MBO type of projection
In this paper, we combine a Piecewise Constant Level Set (PCLS) method with a MBO scheme to solve a structural shape and topology
optimization problem. The geometrical boundary of structure is represented implicitly by the discontinuities of PCLS functions.
Compared with the classical level set method (LSM) for solving Hamilton–Jacobi partial differential equation (H-J PDE) we
don’t need to solve H-J PDE, thus it is free of the CFL condition and the reinitialization scheme. For solving optimization
problem under some constraints, Additive Operator Splitting (AOS) and Multiplicative Operator Splitting (MOS) schemes will
be used. To increase the convergency speed and the efficiency of PCLS method we combine this approach with MBO scheme. Advantages
and disadvantages are discussed by solving some examples of 2D structural topology optimization problems. 相似文献
59.
Mehdi Fakour Alireza Rahbari Erfan Khodabandeh Davood Domiri Ganji 《Journal of Mechanical Science and Technology》2018,32(1):177-183
This study is carried out on the unsteady flow and heat transfer of a nanofluid in a stretching flat plate. Least square method is implemented for solving the governing equations. It also attempts to demonstrate the accuracy of the aforementioned method compared with a numerical one, Runge-Kutta fourth order. Furthermore, the impact of some physical parameters like unsteadiness parameter (S), Prandtl number (Pr) and the nanoparticles volume fraction (?) on the temperature and velocity profiles is scrutinized carefully. Accordingly, the results obtained from this study reveal that the temperature enhances by means of augmenting the nanoparticles volume fraction. At η ∈ {0, 0.5}, the velocity decreases as a result of a rise in nanoparticles volume fraction and at η ∈ {0.5, 1}, an opposite treatment takes place. Moreover, velocity distribution augments by raising the S value, however an inverse trend is observed in temperature values. Moreover, the local skin friction coefficient indicated a notable rise by increasing the S parameter as well as a steady decrease by rising ?. Finally, water-Alumina nanofluid demonstrated better heat transfer enhancement compared to other types of nanofluids. 相似文献
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