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排序方式: 共有1123条查询结果,搜索用时 119 毫秒
121.
以金鲳鱼、草鱼(均为白肉鱼)和鲣鱼、鲐鱼(均为红肉鱼)为原料,利用低场核磁共振技术测定食盐添加量对鱼糜凝胶过程中水分状态的影响,探讨4 种鱼糜不同凝胶阶段水分状态的变化。结果表明:食盐添加量对4 种鱼糜凝胶过程的水分状态存在显著影响;金鲳鱼与草鱼及鲣鱼与鲐鱼的鱼糜凝胶各阶段的水分状态变化趋势相似;食盐添加量对同种鱼糜凝胶过程中的水分分布无影响,其主要影响水分的弛豫时间;水分迁移的变化与鱼种肌球蛋白(盐溶性蛋白)种类及其热稳定性有关;4 种鱼糜凝胶过程中水分状态的变化在一定程度上间接反映出凝胶温度及食盐添加量对鱼糜凝胶结构的影响,导致不同鱼种鱼糜凝胶质量的差异性。 相似文献
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123.
Zixuan CHEN Tao LIU Xiao MA Hanyu TANG Jianyou HUANG Jianzhong PEI 《Frontiers of Structural and Civil Engineering》2022,16(7):896
Because of favorable mechanical properties, deformation resistance and being conducive to environmental protection, honeycomb fabricated plastic pavement slabs are highly recommended these years. At present, most studies focus on the performance of plastic materials, however, the dimension optimization of fabricated plastic pavement slab is rarely mentioned. In this paper, an optimized geometry of the honeycomb pavement slab was determined through finite element analysis. Mechanical response of honeycomb slabs with different internal dimensions and external dimensions were explored. Several dimension factors were taken into consideration including the side length, rib thickness, the thickness of both top and bottom slabs of honeycomb structure and the length, the width and the thickness of the fabricated plastic slab. The results showed that honeycomb pavement slab with 6 cm bottom slab, 12 cm top slab,18 cm side length and 6 cm rib thickness is recommended, additionally, an external dimension of 4 m × 4 m × 0.45 m is suggested. Then, the mechanical responses of this optimized fabricated plastic slab were further investigated. Significance of different influencing factors, including wheel load, elastic modulus of plastic material, base layer thickness, soil foundation modulus and base layer modulus were ranked. 相似文献
124.
Tan Raymond R. Aviso Kathleen B. Lao Angelyn R. Promentilla Michael Angelo B. 《Clean Technologies and Environmental Policy》2022,24(1):173-184
Clean Technologies and Environmental Policy - P-graph causality maps were recently proposed as a methodology for systematic analysis of intertwined causal chains forming network-like structures.... 相似文献
125.
This paper focuses on the novelty pumpless organic Rankine cycle (ORC) and its choice of working fluids. Based on the selection criteria, the refrigerant of R1233zd(E) is firstly chosen and investigated in the pumpless ORC system. In the system, the feed pump is removed, and the refrigerant flows back and forth between two heat exchangers, which act as the evaporator or condenser, respectively. The impacts of the heating water temperature and loads on the system performance are studied to find out the best operating conditions. The low‐grade heat source is simulated by an electric boiler. The temperature of the heat resource ranges from 80°C to 100°C with the interval of 5°C. The temperature of the cooling water inlet is 10°C and is kept constant. The largest average power output is 127 W under the condition of 100°C heating water with nine loads. Because the cycle efficiency with heating steam temperature of 100°C cannot be determined, the highest energy and exergy efficiencies are 3.5% and 17.1%, respectively, for heating water of 95°C with seven loads. The experimental results show that the energy and exergy efficiencies increase with the increase of the heating temperature. The power and current outputs increase when the loads increase under the condition of the constant heating water temperature, whereas the voltage output decreases meanwhile. The generating time increases when the loads increase. This phenomenon is mainly caused by the increasing evaporating pressure and decreasing condensing pressure when the loads increases. 相似文献
126.
127.
Bin Tang Qiuyuan Xiang Zixuan Fang Xing Zhang Zhe Xiong Hao Li Changlai Yuan Shuren Zhang 《Ceramics International》2019,45(9):11484-11490
The CaMg1-xCr2x/3Si2O6 (0?≤?x?≤?0.1) microwave dielectric ceramics were synthesized via conventional solid state reaction. In this study, the effects of Cr3+ substituting for Mg2+ on morphology, crystal structure and microwave dielectric properties of CaMg1-xCr2x/3Si2O6 ceramics were explored. XRD diffraction patterns exhibited that the CaMg1-xCr2x/3Si2O6 ceramics possessed the pure phase of CaMgSi2O6 when x?≤?0.06 and a small amount of secondary phase Ca3Cr2(SiO4)3 for 0.08?≤?x?≤?0.1. SEM micrographs revealed that the substitution of Mg2+ with Cr3+ could decrease the grain size. The apparent density was affected by the concentration of Mg vacancies. The correlation between crystal structure and microwave dielectric properties was investigated through the Rietveld refinement and Raman analysis. The microwave dielectric properties were mainly dependent on relative density, ionic polarizabilities, internal strain ?, disordered structure and MgO6 octahedron distortions. Finally, CaMg1-xCr2x/3Si2O6 (x?=?0.02) ceramics sintered at 1270?°C for 3?h exhibited excellent microwave dielectric properties of εr?=?8.06, Q?×?f?=?89054?GHz, τf?=??44.92182?ppm/ºC. 相似文献
128.
Xiaolong Cai Chenglin Du Zixuan Sun Ran Ye Haijun Liu Yu Zhang Xiangyang Duan Hai Lu 《半导体学报》2021,42(5):37-48
Gallium nitride (GaN)-based high-electron mobility transistors (HEMTs) are widely used in high power and high frequency application fields,due to the outstanding physical and chemical properties of the GaN material.However,GaN HEMTs suffer from degradations and even failures during practical applications,making physical analyses of post-failure devices extremely significant for reliability improvements and further device optimizations.In this paper,common physical characterization techniques for post failure analyses are introduced,several failure mechanisms and corresponding failure phenomena are reviewed and summarized,and finally device optimization methods are discussed. 相似文献
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130.
日立835与8800氨基酸分析仪的应用与比较 总被引:2,自引:0,他引:2
L 8 8 0 0的Thr -Ser、Gly -Ala、Ile -Leu分离度较 835有很大的提高 ,最低检测浓度为 3pmolAsp ,而 835则为 30pmolAsp ,分析时间也较 835缩短 ,成本大大降低而效率大为提高。比较日立 835 - 5 0型与L - 880 0型氨基酸分析仪在分析中的实际应用情况 ,对这两种机型的应用做个总结 ,使二者得到更合理、充分的利用。 相似文献