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31.
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic...  相似文献   
32.
为降低能耗、提高续航里程,本文提出了以提高电机效率为目标的纯电动汽车三档变速传动方案.首先,在分析电机工作特性的基础上提出了三档传动系统参数匹配方法;然后以某纯电动汽车为研究对象,对其驱动系统进行了改动:方案一在不改变原车型动力系统参数的情况下将传动系统由一档改为三档,并运用所提出的方法确定各档位的传动比;方案二在满足整车动力性指标要求下对电机重新选型并匹配三档传动系统;最后利用ADVISOR软件进行NEDC工况仿真分析.结果表明:在不改变原车型动力系统参数的情况下,采用三档传动可使整车的动力性和经济性都有一定的提升,续航里程提高了 9.2%,百公里电耗降低了 1.28 kW·h;重新选型电机后,采用三档传动续航里程提高了 14.1%,百公里电耗降低了 1.87kW·h.  相似文献   
33.
The main drawback of bioglasses is their restricted use in load bearing applications and the consequent need to develop stronger glassy materials. This has led to the consideration of oxynitride glasses for numerous biomedical applications. This paper investigated two different types of glasses at a constant cationic ratio, with and without nitrogen (a N containing and a N-free glass composition) to better understand the effect of N on the biological properties of glasses. The results revealed that the addition of N increased the glass transition temperature, isoelectric point (IEP) and slightly increased wettability. Moreover, compared to N including glass, N-free glass exhibited better anti-bacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), two key bacteria that infect implants. In summary, these in vitro results indicated that amine functional groups existing in N containing glasses which are missing in N-free glasses, caused a slight difference in wetting behavior and a more obvious change in isoelectric point and in bacterial response. N-free glasses exhibited better inhibitory results both against E. coli and S. aureus compared to N including glass suggesting that oxygen rich glasses should be further studied for their novel antibacterial properties.  相似文献   
34.
The influence of the microstructure on the corrosion rate of three monolithic SiC samples in FLiNaK salt at 900 °C for 250 h was studied. The SiC samples, labeled as SiC-1, SiC-2, and SiC-3, had corrosion rates of 0.137, 0.020, and 0.043 mg/cm2h, respectively. Compared with grain size and the presence of special grain boundaries (i.e., Σ3), the content of high-angle grain boundaries (HAGBs) appeared to have the strongest influence on the corrosion rate of SiC in FLiNaK salt, since the corrosion rate increased six times as the concentration of high-angle grain boundaries increased from 19 to 32% for SiC-2 and SiC-1, respectively. These results stress the importance of controlling the content of HAGBs during the production process of SiC.  相似文献   
35.
The corrosion mechanisms of T24, T92, VM12, and AISI 304 steels are studied under the influence of NaCl–KCl, NaCl–Na2SO4, and KCl–K2SO4 salt mixtures in a dry air atmosphere at 650°C for 15 days. NaCl–KCl was the most aggressive deposit and AISI 304 stainless steel exhibited the highest corrosion resistance. There was no relation between the Cr content of the ferritic steels and their corrosion resistance in NaCl–KCl. In contrast, the resistance of high-Cr steels was better when exposed to NaCl–Na2SO4 and KCl–K2SO4. The high-Cr and the low-Cr steels were more susceptible to NaCl–Na2SO4 and to KCl–K2SO4, respectively.  相似文献   
36.
Treating neuroinflammation-related injuries and disorders through manipulation of neuroinflammation functions is being heralded as a new therapeutic strategy. In this study, a novel pectic galactan (PG) polysaccharide based gene therapy approach is developed for targeting reactive gliosis in neuroinflammation. Galectin-3 (Gal-3) is a cell protein with a high affinity to β-galactoside sugars and is highly expressed in reactive gliosis. Since PG carries galactans, it can target reactive gliosis via specific carbohydrate interaction between galactan and Gal-3 on the cell membrane, and therefore can be utilized as a carrier for delivering genes to these cells. The carrier is synthesized by modifying quaternary ammonium groups on the PG. The resulting quaternized PG (QPG) is found to form complexes with plasmid DNA with a mean diameter of 100 nm and have the characteristics required for targeted gene therapy. The complexes efficiently condense large amounts of plasmid per particle and successfully bind to Gal-3. The in vivo study shows that the complexes are biocompatible and safe for administration and can selectively transfect reactive glial cells of an induced cortical lesion. The results confirm that this PG-based delivery system is a promising platform for targeting Gal-3 overexpressing neuroinflammation cells for treating neuroinflammation-related injuries and neurodegenerative diseases.  相似文献   
37.
为了开展坛紫菜高值化加工利用,以坛紫菜为原料、蛋白质提取率为评价指标,通过考察提取溶剂、超声时间和功率、料液比、pH等单因素实验、正交试验设计优化超声波提取工艺,对其等电点、乳化性、起泡性等基础特性进行分析,并进行抗氧化活性测定。结果表明,在超声全程时间50 min、超声功率1350 W条件下,坛紫菜蛋白质提取率为60.98%±1.01%。同时通过对所提取的坛紫菜蛋白质特性分析结果显示,坛紫菜蛋白质的等电点为4.5,在等电点附近,坛紫菜蛋白质有较好的泡沫稳定性,可达80.84%±2.95%;抗氧化测定结果显示,坛紫菜蛋白质在5~50 mg/mL范围内具有较强的抗氧化活性,浓度为50 mg/mL时,总抗氧化能力为2.89±0.09 U/mL,ABTS+自由基清除能力相当于0.83±0.08 mmol/L Trolox,DPPH清除率在10 mg/mL时达到68.04%±0.73%。该研究可以为坛紫菜资源的开发利用提供一定的理论依据和技术支持。  相似文献   
38.
Polymer Bulletin - In this study, we synthesized a new ion-imprinted polymer (IIP) based on introduction of amidoxime groups in acrylonitrile, complexation with Cd2+ ions and polymerization with...  相似文献   
39.
医院建筑项目是非常复杂且具有挑战性的建设项目。传统的交付模式无法满足人们对医院建筑建设、运营方面的高要求,为此开展面向医院建筑项目的IPD模式应用研究。在对IPD模式发展现状整理的基础上,阐述医院建筑项目IPD模式的适用性。分析采用IPD模式的医院建筑项目特点,并以上海市某公立三甲专科医院项目为例,对IPD模式在国内的应用进行探索性研究。  相似文献   
40.
Debittered trub (brewing waste) is an important source of protein source (70.26%). Trub and whey protein were used for 5% protein enrichment of ice cream frozen by liquid nitrogen. Three formulations were elaborated: ice cream standard (ICS), ice cream with whey protein (ICW) and ice cream with trub (ICT). Chemical composition, rheological properties, texture, overrun, melting rate, scanning electron microscopy and a sensorial test were performed. Results showed that ICT presented a higher viscosity, obtained on the upward curve up to 6.76 Pa s−1, consistency index (22.96 (Pa s−1)n), hysteresis area (140.40 mPa s−1) and hardness (31113.33 g) but a lower melting rate (0.38 g min−1), overrun (13.92%) and sensorial acceptability than the other formulations. The addition of trub debittered for protein enrichment improved ice cream properties and demonstrated that it could be used as a food ingredient.  相似文献   
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