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排序方式: 共有2495条查询结果,搜索用时 15 毫秒
1.
Fangshuai Peng Huaxi Yi Qi Li Weili Xu Rongchun Wang 《International Journal of Food Properties》2018,21(1):1190-1202
This work aims at improving the textural and whipping properties of whipped cream by the addition of milk fat globule membrane protein. The determination of particle size distribution and average diameter of whipped cream showed that the small particle size was shifted to a larger range after milk fat globule membrane protein was added. The average particle size (d3,2) of whipped cream reached a maximum value of 5.05 µm at 1% milk fat globule membrane protein, while slowly decreased with increasing milk fat globule membrane protein levels from 2% to 5%. In addition, the partial coalescence of fat increased with the increase of milk fat globule membrane protein levels, and the correlation between the whipping time and the overrun of whipped cream was positive. The addition of milk fat globule membrane protein also altered the rheological behaviour of whipped cream, resulting in the increase of modulus G′ and the loss modulus G″. The results also indicated that higher milk fat globule membrane protein level decreased the serum loss of whipped cream while improved its stability. While milk fat globule membrane protein levels had no significant effect on viscosity, its increasing levels effectively improved the hardness, consistency, and viscosity of whipped cream. 相似文献
2.
在全钢载重子午线轮胎胎面胶中加入不同用量炭黑N234,并将白炭黑与炭黑并用,考察炭黑用量和添加白炭黑对胶料性能的影响。结果表明:随着炭黑N234用量增大,不添加白炭黑的胶料Fmax和门尼粘度增大,门尼焦烧时间呈缩短趋势;密度、硬度和定伸应力提高,拉伸强度和回弹值降低,撕裂强度先提高后降低,耐磨性能提高,生热增大,炭黑用量不宜过大;在填料用量相当的条件下,添加白炭黑的胶料门尼粘度较小,门尼焦烧时间较短,撕裂强度和耐磨性能显著提高,生热明显降低;随着炭黑用量增大,不添加白炭黑的胶料弹性模量和损耗因子总体提高;总体来看,添加45份炭黑N234和10份白炭黑的胎面胶滞后损失和生热较低。 相似文献
3.
《Ceramics International》2022,48(15):21600-21609
Stereolithography (SL) shows advantages for preparing alumina-based ceramics with complex structures. The effects of the particle size distribution, which strongly influence the sintering properties in ceramic SL, have not been systematically explored until now. Herein, the influence of the particle size distribution on SL-manufactured alumina ceramics was investigated, including bending strength at room temperature, post-sintering shrinkage, porosity, and microstructural morphology. Seven particle size distributions of alumina ceramics were studied (in μm/μm: 30/5, 20/3, 10/2, 5/2, 5/0.8, 3/0.5, and 2/0.3); a coarse:fine particle ratio of 6:4 was maintained. At the same sintering temperature, the degree of sintering was greater for finer particle sizes. The particle size distribution had a larger influence on flexural strength, porosity and shrinkage than sintering temperature when the particle size distribution difference reached 10-fold but was weaker for 10 μm/2 μm, 5 μm/2 μm and 5 μm/0.8 μm. The sintering shrinkage characteristics of cuboid samples with different particle sizes were studied. The use of coarse particles influenced the accuracy of small-scale samples. When the particle size was comparable to the sample width, such as 30 μm/5 μm and 5 mm, the width shrinkage was consistent with the height shrinkage. When the particle size was much smaller than the sample width, such as 2 μm/0.3 μm and 5 mm, the width shrinkage was consistent with the length shrinkage. The results of this study provide meaningful guidance for future research on applications of SL and precise control of alumina ceramics through particle gradation. 相似文献
4.
Florian Röper Markus Wolfahrt Sandra Schlögl Georg Kucher Gerald Pinter 《应用聚合物科学杂志》2019,136(19):47506
Repair of composite structures and the impact of demanding environmental conditions is a crucial issue for the aircraft industry because of the increasing use of composites in modern aircraft. Consequently, the impact of environmental conditions common for aircraft applications on repair specimens in comparison to nonrepaired specimens is studied. All specimens are produced from a woven carbon fiber-reinforced epoxy-based prepreg. For the repair-specimens, an epoxy-based film adhesive is used for the soft patch repair approach. During the repair process, the surface of the precured prepreg is prepared by a mechanical method (sanding) and an additional chemical functionalization, respectively. Moisture absorption of the repair specimens is independent of the surface preparation method and higher for the repaired than for the nonrepaired specimens. The key influencing environmental conditions for the tensile strength and the failure mode of the repair specimens are elevated temperature testing as well as hot/wet conditioning and conditioning in deionized water. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47506. 相似文献
5.
In this work, the effect of ZrB2 (0, 5, 10 and 20?vol%) ceramic reinforcement on densification, structure, and properties of mechanically alloyed Al was investigated. The milling of Al-ZrB2 powder compositions resulted in formation of agglomerates with varied size. In particular, the size of agglomerates was reduced considerably with increased addition of ZrB2 to Al. Interestingly, the densification of hot pressed Al increased from 96.06% to 99.22% with ZrB2 addition. The reduction of agglomerates size was attributed to the enhanced densification of Al-ZrB2 composites. Pure Al showed relatively low hardness (0.94?GPa) and it was improved to 1.78?GPa with the addition of 20?vol% ZrB2. The mechanical properties have significantly been improved for Al-ZrB2 composites. Especially Al - 20?vol% ZrB2 possessed a very high yield strength (529?MPa), compressive strength (630?MPa) and compressive strain of 19.25%. Realization of such a good combination of mechanical properties is the highest ever reported for Al composites so far in the literature. The coefficient of friction (COF) of Al-ZrB2 varied narrowly between 0.33 and 0.40 after dry sliding wear against steel disc. The wear rate of Al-ZrB2 composites was within mild wear regime and varied between 98.88?×?10?6 and 34.66?×?10?6 mm3/Nm. Among all the compositions, Al - 20?vol% ZrB2 composite exhibited the lowest wear rate and high wear rate was noted for pure Al. Mild abrasion, tribo-oxidation, third body wear (wear debris) and delamination were the major material removal mechanisms for Al-ZrB2 composites. Overall the hardness, strength and wear resistance of Al - 20?vol% ZrB2 composite was improved by 84.3%, 84.3% and 64.2%, respectively when compared to pure Al. 相似文献
6.
María T. Colomer Lidia Zur Maurizio Ferrari Angel L. Ortiz 《Ceramics International》2018,44(11):11993-12001
Rhabdophane-type Eu3+,Tb3+-codoped LaPO4·nH2O single-crystal nanorods with the compositions La0.99999-xEuxTb0.00001PO4·nH2O (x?=?0–0.03), La0.99999-yTbyEu0.00001PO4·n′H2O (y?=?0–0.010), and La0.99999-zTbzEu0.000007PO4·n′′H2O (z?=?0–0.012) were hydrothermally synthesized with microwaves. It is shown that the Eu3+,Tb3+ codoping does not affect the thermal stability of these nanorods, which is due to the formation of substitutional solid solutions with both Eu3+ and Tb3+ replacing La3+ in the crystal lattice. Moreover, it is also shown that monazite-type Eu3+,Tb3+-codoped LaPO4 single-crystal nanorods can be obtained by calcining their rhabdophane-type Eu3+,Tb3+-codoped LaPO4·(n,n′ or n′′)H2O counterparts at moderate temperature in air, and that they are thermally stable. It is also observed that, for the same Eu3+,Tb3+-codoping content, the monazite-type Eu3+,Tb3+-codoped LaPO4 nanorods exhibit higher photoluminescent efficiency than the rhabdophane-type Eu3+,Tb3+-codoped LaPO4· (n,n′ or n′′)H2O nanorods. Moreover, it is found that the highest photoluminescence emission corresponds to the monazite-type La0.96999Eu0.02Tb0.00001PO4 nanorods for the La0.99999-xEuxTb0.00001PO4 system. However, for those compositions energy transfer from Tb3+ to Eu3+ does not occur. In addition, for an efficient energy transfer to occur, a content of at least 1?mol% Tb3+ is needed in all the studied materials. 相似文献
7.
《Ceramics International》2021,47(21):30298-30309
The novel Al4O4C–(Al2OC)1-x(AlN)x–Zr2Al3C4–Al2O3 refractories with ultra-low carbon content have been successfully prepared by constructing the core-shell structure of aluminum at 1300–1700°C in nitrogen. The phase composition, microstructure, and properties of the novel refractories are deeply investigated. The cracking temperature on the core-shell structure of aluminum is further explored and the reaction mechanism of Zr2Al3C4 has also added explanation. The results show that the novel refractories have excellent physical properties and cannot be corroded by molten iron. There exist two different Al2OC solid solutions in the novel refractories, Al2OC-rich (Al2OC)1-x(AlN)x and AlN-rich (Al2OC)1-x(AlN)x. The temperatures affect their relative content. When temperatures are less than 1600°C, the relative content of Al2OC-rich (Al2OC)1-x(AlN)x is more than that of AlN-rich (Al2OC)1-x(AlN)x. When temperatures are above 1700°C, the relative content of AlN-rich (Al2OC)1-x(AlN)x is more than that of Al2OC-rich (Al2OC)1-x(AlN)x. The core-shell structure of aluminum fully ruptures at about 1200°C. Zr2Al3C4 begins to form at about 1000°C and generates in large at 1200°C. 相似文献
8.
Luyang Miao Yang Bai Yufei Yuan Changli Lü 《International Journal of Hydrogen Energy》2018,43(36):17461-17474
Chemical crosslinking is regard as an effective method to balance the ionic conductivity and dimensional stability of anion exchange membranes (AEMs). In this work, a series of crosslinked AEM composite membranes based on polydopamine-functionalized reduced graphene oxide (PDArGO) were constructed from quaternized polysulfone (QPSU) with amino groups via mussel-inspired chemistry strategy. On the one hand, as the dopant, the hydrogen bonding interaction between PDArGO and a large number of amino groups on the side chains of QPSU can enhance the water uptake of the membranes and has a positive influence on the ionic conductivity of composite membranes. On the other hand, PDArGO also acts as the crosslinker, which can form a micro-crosslinked structure with the amino groups on the side chains of the polymer through the Michael addition/schiff base reactions. Under the combined influence of the above two factors, the crosslinked composite AEMs exhibited special delightful properties. In general, the crosslinking reaction will lead to the decrease of the ionic conductivity of the membranes, but as for the membranes prepared by us, the ionic conductivity had been improved to some extent. Especially, the QPSU-1.5%-PDArGO exhibited 57% improvement in the hydroxide conductivity than that of pure QPSU membrane and reached the highest value of 61 mS cm?1 at 80 °C. Besides, the crosslinked membranes also exhibited strong dimensional stability, good mechanical strength, comparable alkaline stability and improved methanol permeability. 相似文献
9.
Angela M. Gutierrez Rohit Bhandari Jiaying Weng Arnold Stromberg Thomas D. Dziubla J. Zach Hilt 《应用聚合物科学杂志》2020,137(37):49109
In this work, the development of novel magnetic nanocomposite microparticles (MNMs) via free radical polymerization for their application in the remediation of contaminated water is presented. Acrylated plant-based polyphenols, curcumin multiacrylate (CMA) and quercetin multiacrylate (QMA), were incorporated as functional monomers to create high affinity binding sites for the capture of polychlorinated biphenyls (PCBs), as a model pollutant. The MNMs were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, dynamic light scattering, and UV–visible spectroscopy. The affinity of these novel materials for PCB 126 was evaluated and fitted to the nonlinear Langmuir model to determine binding affinities (KD). The results suggest the presence of the polyphenolic moieties enhances the binding affinity for PCB 126, with KD values comparable to that of antibodies. This demonstrates that these nanocomposite materials have promising potential as environmental remediation adsorbents for harmful contaminants. 相似文献
10.
《International Journal of Hydrogen Energy》2020,45(27):14119-14132
The bipolar plate (BP) material should possess contradictory properties. They should also manufacture from low-cost methods and materials. In the current investigation, thermoset-based composite materials reinforced with conductive fillers, and the compression molding process is implemented. In addition to fabricating the bipolar plates (BPs) with and without the flowing channels, alleviating the defects during the molding process is performed. The channels are perfectly formed on the plates with the designed depth of 0.65 mm and 0.5 mm of width. In the meanwhile, we alleviate different molding defects, which spoil the surface appearance and part properties. Regarding the physical properties, the water contact angle is measured to be around 85°. The through-plane electrical conductivity of molded plates showed high values up to 38 S/cm, and the interfacial contact resistance measured to be 18–24 mΩ cm2. The mean value of the flexural strength of the produced samples was equal to 47 MPa, which is almost twice the DOE target (>25 MPa). 相似文献