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911.
Daodong Pan Jinxuan Cao Lili Wang Xiaoqun Zeng 《International Journal of Food Science & Technology》2012,47(1):160-166
Calcium chloride (CaCl2) and phosphates are important additives to improve product quality during meat processing. Response surface methodology was used to study the influence of CaCl2 and phosphates on the hardness, water‐holding capacity (WHC) and ultra‐structure of salt‐soluble goose meat protein gels. The results show that the hardness and WHC of salt‐soluble protein gels increased significantly when CaCl2 concentration was increased and phosphates were added. Scanning electron microscopy showed that tetrasodium pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) had a greater impact on the cross‐linking and pore diameter of the gel networks than sodium hexametaphosphate (SHMP). At the 0.02 m and 4:3:2 of CaCl2 concentration and the ratio of TSPP, SHMP and STPP, hardness and WHC values were 114.55 gf and 96.65%, which corresponded to the prediction value of our model. Further results showed that the hardness and WHC of gels reached the maximum with 0.3% of phosphates levels. 相似文献
912.
A challenging task in injection molding industry is to minimize shrinkage and warpage (S&W) through optimal setting of molding conditions. In determining the relationship between molding conditions and product dimension, most existing literature considered S&W as a whole entity or focused on only one of them. The intention of this study was to distinguish these two terms, and perform a thorough analysis on the effect of operative conditions on S&W during injection molding process through a combination of experimental and numerical methods. Six process parameters with five levels were examined on a box-shaped product, and the single factor analysis of variance (ANOVA) was adopted in identifying the significance of each variable in the experiment. Results indicated that the effect of processing conditions on shrinkage is different from that on warpage. Specifically, packing pressure affects shrinkage most while packing time is the dominant factor in determining warpage. The reaction of shrinkage to packing pressure is monotonic, whereas the plot of warpage shows a U-shaped variation. A differential treatment of S&W can therefore help to enhance product quality. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
913.
Changes in the phenolic contents and antioxidant activities of citrus peels from different cultivars after in vitro digestion 下载免费PDF全文
Dongxiao Su Hesheng Liu Qingzhu Zeng Xiangyang Qi Xueshuang Yao Jie Zhang 《International Journal of Food Science & Technology》2017,52(11):2471-2478
The aim of this study was to investigate the effects of in vitro digestion on the phenolic contents and antioxidant activities of citrus peels. Three different varieties of citrus peels (mandarin, ponkan and red tangerine) were treated with simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). The results showed that the SGF or SIF treatments of the citrus peels did not significantly increase the total phenolic content (TPC) or total flavonoid content (TFC), except for that of the TFC of ponkan peel treated with SGF. However, simulated in vitro digestion did improve the antioxidant activities measured with FRAP and ABTS methods. The effect of SGF was more positive than those of SIF for the FRAP assay, but the opposite was true for ABTS. Notably, both simulated digestion techniques decreased the DPPH free radical scavenging abilities. Simulated digestion in vitro changed the antioxidant activities of the citrus peels. 相似文献
914.
915.
Zou Sumeng Yang Qinghe Zeng Shuangqin Nie Hong 《中国炼油与石油化工》2014,16(4):1-6
A series of pseudo-boehmite samples with their sulfate radicals(SO42-) concentration ranging from 0.9% to 3.0%were prepared by the reaction of NaAlO2 solution on Al2(SO4)3 solution. The existing form of sulfate radicals was investigated.Results have shown that sulfates in pseudo-boehmite included two parts, the soluble sulfate radicals and the insolublesulfate radicals, which accounted for 99% of the total amount of sulfate radicals. XRD, low-temperature N2-adsorption, andTEM were used to characterize the properties of these pseudo-boehmite samples. Results have shown that the relative crystallinityand crystal size of pseudo-boehmite decreased with the increase of sulfate radicals in the support. In the meanwhile,the bound water content in pseudo-boehmite increased. The TEM images of pseudo-boehmite indicated that the pseudoboehmitewas prone to become amorphous hydrated alumina. However, the effect of sulfate content on the specific surfacearea and pore structure of aluminium oxide was insignificant. 相似文献
916.
Zeng Zhang Christine M. Jackson Aaron R. Arehart Brian McSkimming James S. Speck Steven A. Ringel 《Journal of Electronic Materials》2014,43(4):828-832
The energy band alignments of Ni/Al2O3/GaN heterostructures have been explored by internal photoemission (IPE) and capacitance–voltage (CV) measurements. By performing IPE measurements at both reverse- and forward-bias conditions, the Ni/Al2O3 Schottky barrier is found to be 2.9 ± 0.1 eV with the presence of a strong image force lowering effect, while the Al2O3/GaN conduction-band offset is determined to be 2.2 ± 0.1 eV and is insensitive to oxide electrical field. CV-based flat-band voltage analysis has further been performed on samples with different oxide thicknesses, not only confirming the IPE-measured band alignment but also revealing the presence of 3.0 × 1012 cm-2 net positive charge at the Al2O3/GaN interface. 相似文献
917.
Mingming Zhang Jinghui Cao Sheng Q. Xie Guoli Zhu Xiangfeng Zeng Xiaolin Huang Qun Xu 《Journal of Intelligent and Robotic Systems》2018,91(2):207-215
This paper involves the use of a compliant ankle rehabilitation robot (CARR) for the treatment of drop foot. The robot has a bio-inspired design by employing four Festo Fluidic muscles (FFMs) that mimic skeletal muscles actuating three rotational degrees of freedom (DOFs). A trajectory tracking controller was developed in joint task space to track the predefined trajectory of the end effector. This controller was achieved by controlling individual FFM length based on inverse kinematics. Three patients with drop foot participated in a preliminary study to evaluate the potential of the CARR for clinical applications. Ankle stretching exercises along ankle dorsiflexion and plantarflexion (DP) were delivered for treating drop foot. All patients gave positive feedback in using this ankle robot for the treatment of drop foot, although some limitations exist. The proposed controller showed satisfactory accuracy in trajectory tracking, with all root mean square deviation (RMSD) values no greater than 0.0335 rad and normalized root mean square deviation (NRMSD) values less than 6.7%. These preliminary findings support the potentials of the CARR for clinical applications. Future work will investigate the effectiveness of the robot for treating drop foot on a large sample of subjects. 相似文献
918.
Nitrogen (N) and phosphorus (P) co-doped anatase TiO2 nanosheets were realized by low-temperature self-doping N–TiO2 followed by high-temperature P doping with foreign precursor. It is found that P doping process can maintain good TiO2 nanosheets morphology with exposed {001} facets. Chemical state of dopants indicates that N and P atoms replace O on O sites in TiO2 lattice. Compared with pure TiO2 and N-doped TiO2, N–P co-doped TiO2 nanosheets exhibits stronger optical absorption and higher degradation rate of dye molecules in visible light regime. The enhanced photocatalytic properties are attributed to two factors. On one hand, N–P co-doping can effectively reduce band gap of TiO2 from 3.20 to 2.48 eV, leading to an enhancement of the absorption in visible light regime. On the other hand, the presence of exposed {001} facets of TiO2 nanosheets can induce the effective separation of photogenerated electrons and holes in reaction. 相似文献
919.
920.
Group behavior forecasting is an emergent research and application field in social computing. Most of the existing group behavior
forecasting methods have heavily relied on structured data which is usually hard to obtain. To ease the heavy reliance on
structured data, in this paper, we propose a computational approach based on the recognition of multiple plans/intentions
underlying group behavior.We further conduct human experiment to empirically evaluate the effectiveness of our proposed approach. 相似文献