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141.
迷迭香是重要的经济作物,其提取物中含有酚酸类、黄酮类、萜类等多种生物活性物质,具有抗氧化、抑菌等重要的生理功能,因此可作为天然抗氧化剂、天然抑菌剂应用于生产中。本文综述了迷迭香提取物目前采用的提取、纯化方法,提高提取物稳定性所应用的微胶囊技术、纳米颗粒载体技术和复合涂膜技术。重点讨论了迷迭香提取物的抗氧化、抑菌活性,以及在肉类制品、蔬菜水果、油脂、饮料等加工过程中的具体应用。最后对迷迭香提取物的不足和后续研究进行了讨论与展望,为迷迭香提取物的进一步推广应用提供参考。 相似文献
142.
以冠县灵芝为研究对象,采用传统浸提法获得水溶性灵芝多糖GLP,经Sevag法去蛋白及活性炭脱色,然后依次采用Capto TM DEAE离子柱层析和Superdex 6 prep Grad凝胶柱层析进行分离纯化,获得均一多糖GLPS80a,经高效凝胶色谱(HPGPC)法检测,其相对分子量为9024 Da,高效阴离子色谱(HPAEC)、红外光谱(FT-IR)和核磁共振(NMR)图谱分析结果表明,GLPS80a是由岩藻糖(Fuc)、氨基葡萄糖(GlcN)、半乳糖(Gal)、葡萄糖(Glc)、木糖(Xyl)、甘露糖(Man)和葡萄糖醛酸(GluA)等7种单糖组成,摩尔比为0.06:0.23:0.17:1.00:0.08:0.19:0.23,主要以β-D-(1,6)糖苷键连接的吡喃糖为主要组成且不含三股螺旋的酸性多糖。抗氧化结果表明,GLPS80a具有一定的DPPH自由基、OH自由基和ABTS+自由基的清除能力,它们的EC50分别为7.40、8.74和0.33 mg/mL,还原力RP0.5AU为8.33 mg/mL。本研究将为合理开发冠县灵芝资源和精深... 相似文献
143.
144.
Chao Lu Xiaoxue Liu Yufei Xia Qing Li Leping Dang Xinyi He Zhanzhong Wang 《化学工程与技术》2020,43(3):422-428
Measurement methods of metastable zone width (MZW) and nucleation induction time for melting layer crystallization of palm oil (PO) and its olein/stearin (POL/PST) were established, and the effects of cooling rate (corresponding to various supercoolings) on MZWs and induction time for melting layer crystallization of PO, POL, and PST were determined. The results indicated that the MZW coherently rose with increasing cooling rates with respect to PO and POL, while it declined with higher cooling rates for PST. The induction period results demonstrated that the nucleation induction periods of PO, PST, and POL decreased with increasing supercoolings, and the lag time for nucleation negatively correlated to the melting point of oils at the same supercooling. These data could offer significant instruction in designing and controlling the melting layer crystallization process for palm oil. 相似文献
145.
Chenqiu Du Baizhan Li Wei Yu Jiao Cai Lexiang Wang Xinyi Li Yinghui Yao Bicheng Li 《Indoor air》2021,31(2):541-556
Despite concerns about building dampness and children’ health, few studies have examined the effects of building energy efficiency standards. This study explored the connections between self-reported household dampness and children’ adverse health outcomes across buildings corresponding to construction periods (pre-2001, 2001-2010, post-2010). Significant differences of dampness-related indicators were found between buildings; the prevalence was remarkable in pre-2001 buildings. The prevalence of lifetime-ever doctor-diagnosed diseases for children was significantly associated with building dampness (adjust odd ratios > 1), but was not affected by construction periods. The hygrothermal performance for a typical residence was simulated, varying in U-values of envelopes and air change rates. The simulated performance improvement increased indoor temperatures in 2001-2010 and post-2010 buildings. The frequency with higher indoor relative humidity was higher in pre-2001 buildings, leading to the highest values for maximum mold index (Mmax) on wall surface, especially in winter. Compared to buildings in 2001-2010, increased insulation and lower air change rate led to a relatively higher relative humidity in post-2010 buildings, adversely increasing the Mmax values. The findings addressed the positive and negative role of building standard development, which help suggesting appropriate environmental and design solutions to trade-off energy savings and dampness/mold risk in residences. 相似文献
146.
利用录像和视频处理技术以及单片机原理,设计了一种新型智能判读系统,提出了一种新型的判读方法,即通过录像测量靶场光测仪器脱靶量的先进方法(简称视频判读).它把电视实时测量和事后判读的优点结合起来,代替了当前通用的胶片半自动判读仪。新型判读方法的研究成功,是胶片半自动判读的重要补充和发展,提高了靶场光电测量的效率,改变了靶场数据处理的面貌,推动电视测量的发展及新一代光电自动经纬仪的诞生。 相似文献
147.
给出了翻板式车库门提升机构的ADAMS建模过程;对样机模型进行了仿真分析;并在此基础上,对样机拉杆部位实现了优化设计.试验表明,优化设计有效地克服了提升过程末端驱动力的大幅波动. 相似文献
148.
试验研究了普通和超声切削新型颗粒增强金属基复合材料SiCp/Al的切削特性 ,得到超声振动切削该材料的切屑形态、切削力变化规律 相似文献
149.
Lin Gan Zhida Xu Zhiheng Wang Binbin Li Wei Li Xinyi Cai Kunkun Liu Qiumin Liang Shi‐Jian Su 《Advanced functional materials》2019,29(20)
Designing thermally activated delayed fluorescence (TADF) materials with an efficient reverse intersystem crossing (RISC) process is regarded as the key to actualize efficient organic light‐emitting diodes (OLEDs) with low efficiency roll‐off. Herein, a novel molecular design strategy is reported where a typical TADF material 10‐phenyl‐10H, 10′H‐spiro[acridine‐9, 9′‐anthracen]‐10′‐one (ACRSA) is utilized as a functional electron donor to design TADF materials of 2,4,6‐triphenyl‐1,3,5‐triazine(TRZ)‐p‐ACRSA and TRZ‐m‐ACRSA. It is unique that the intramolecular charge transfer of the ACRSA moiety and the intramolecular and through‐space intermolecular charge transfer between the TRZ and ACRSA moieties, provide a “multichannel” effect to enhance the rate of the reverse intersystem crossing process (krisc) exceeding 10?6 s?1. TADF OLEDs based on TRZ‐p‐ACRSA as an emitter show a maximum external quantum efficiency (EQE) of 28% with reduced efficiency roll‐off (EQEs of 27.5% and 22.1% at 100 and 1000 cd m?2, respectively). Yellow phosphorescent OLEDs utilizing TRZ‐p‐ACRSA as a host material show record‐high EQE of 25.5% and power efficiency of 115 lm W?1, while phosphorescent OLEDs based on TRZ‐m‐ACRSA show further lower efficiency roll‐off with EQEs of 25.2%, 24.3%, and 21.5% at 100, 1000, and 10 000 cd m?2, respectively. 相似文献
150.
Zou Deyue Liu Jie Cheng Xinyi Zhang Jing Liu Yunfeng Ma Shouchuan 《Mobile Networks and Applications》2020,25(5):1683-1693
Mobile Networks and Applications - Communication problems standout as the key issue needing to be addressed in Unmanned Aerial Vehicle (UAV) applications. Nowadays, the application of Artificial... 相似文献