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1.
Incorporating high level of potato flour into wheat flour enhances nutritional values of bread but induces a series of problems that lead to the decline of the bread quality. To overcome the barrier, wheat gluten and carboxymethylcellulose (CMC) were added into potato–wheat composite flour to improve dough machinability and bread quality. The rheological properties, thermo-mechanical properties and microstructures of dough were investigated. The results showed that the interaction between gluten and CMC mitigated the discontinuity of gluten matrix and gluten protein aggregation caused by the addition of potato flour, which yielded a more branched and compact gluten network. The compact three-dimensional viscoelastic structure induced improvements of gas retention capacity and dough stability, making it mimic the machinability properties of wheat flour dough. Bread qualities were apparently improved with the combined use of 4% gluten and 6% CMC, of which specific volume increased by 42.86%, and simultaneously, hardness reduced by 75.93%.  相似文献   
2.
Rare-earth doped strontium barium niobates were synthesized using usual ceramic technique. The dopants are La, Ce, Gd, Sm and Nd. The materials were characterized by XRD and density measurements. The grain sizes were determined from SEM analysis. Lattice parameters changed uniformly with rare-earth dopants in unfilled structures. Density measurements and SEM analysis confirmed only minute changes in the densities of the ceramics.  相似文献   
3.
Spray forming involves sequential gas atomization of a melt into a spray of fine droplets and their deposition on a substrate to build up a high-density preform. The rapid solidification inherent in spray deposition generates refined, equiaxed and low segregation microstructures. A number of promising features of this near-net shape manufacturing process are highlighted and compared, wherever possible, with the conventional casting and PM techniques. Some commercial nozzles used to create spray and mechanisms associated with spray generation are described. The consolidation of the droplets and the development of the microstructure in the deposit are primarily governed by the nature of the spray and the thermal state of droplets on the deposition surface. Several microstructural characteristics of the deposit are presented and their origin in spray deposition is discussed.  相似文献   
4.
采用步进轧制工艺制备了Ti-6-22-22S合金Ф50mm棒材,对加工、热处理、组织与性能的关系进行了分析。结果表明:在两相区上部温度960℃轧制获得细网篮组织,棒材性能较好且数据均匀;热处理后,得到双态组织,强度.塑性达到优良组合,而片层状组织强度较高,但塑性稍低。  相似文献   
5.
The Y2O3: Yb3 , Er3 microstructures were fabricated by a hydrothermal method without surfactants.The microstructures structure was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM,KYKY 1000B).The up-conversion luminescence spectra were studied under 978 nm laser diode excitation.In Yb3 and Er3 codoped Y2 O3 microcrystals, the relative intensity of green emission became stronger as the morphology of sample changed from wires to films.  相似文献   
6.
Burnishing is used increasingly as a finishing operation which gives additional advantages such as increased hardness, fatigue strength, and wear resistance. Experimental work based on 34 factorial design was carried out to establish the effects of ball burnishing parameters on the surface hardness of high-strength low alloy steels (HSLA) dual-phase (DP) steel specimens. Statistical analysis of the results shows that the speed, feed, lubricant and ball diameter have significant effect on surface hardness.  相似文献   
7.
利用高分辨透射电子显微镜(HRTEM)及电子能量损失谱(EELS)对室温下注入氢离子的CeO2烧结体的显微组织结构和价态进行了原位观察和分析。结果表明:室温注氢,虽可以使严重损伤区内氧的状态发生明显改变,却不能引起CeO2的相转变及Ce的价态改变;这一结果可能与氢离子因尺寸太小不能占据CeO2的正常格点位置从而无法有效形成氧空位以及室温下CeO2中Ce和O的扩散比较困难等因素有关。  相似文献   
8.
The interfacial microstructures of 96 and 98% polycrystalline alumina joined with single crystal sapphire have been investigated in relation to the joining parameters. Joining has been evaluated based on either using a thin spin-on silica interlayer or by placing the alumina and sapphire in direct contact. The materials were joined by placing the coated or uncoated surfaces in contact and heating in the range of 1340–1475 °C with minimum external load. With the aid of a silica interlayer, sapphire and 98% polycrystalline alumina were successfully joined in 180 min at 1400 °C and above, while samples without a silica interlayer failed to join under these conditions. However, sapphire and 96% polycrystalline alumina were joined both with and without the use of silica interlayer. A variety of interfacial morphologies have been observed, including amorphous regions, fine crystalline alumina, and intimate contact between the sapphire and polycrystalline alumina.  相似文献   
9.
低碳钢热浸Zn-0.15%Ni合金镀层组织及第二相粒子   总被引:1,自引:0,他引:1  
采用热浸Zn-Ni合金镀锌方法,在含0.03%-0.36%Si的低碳钢上获得Zn-Ni合金镀层,研究了镀浴中Ni含量和钢中Si含量对镀层中δ相和ζ相生长速率的影响,以及Zn-Ni合金镀层η相中的第二相粒子即Zn-Fe-Ni三元化合物Γ2相粒子的形成和长大过程,结果表明,在Zn-0.15%Ni镀浴中,含硅0.03%-0.215%钢镀层的ζ相明显受到抑制,δ相厚度略有增加,Γ2相粒子的形成和长大过程包括ζ相的溶解,Γ2相的形核和成比例吸收铁,镍而长大。  相似文献   
10.
光激励和光检测微型硅谐振器研究   总被引:2,自引:1,他引:1  
分析了光激励谐振器振动的检测问题,用调制激光束激励谐振器使其发生振动,并采用光学干涉的方法测量了这种微振动。  相似文献   
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