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排序方式: 共有2517条查询结果,搜索用时 15 毫秒
1.
Wenjie Liu Jianmin Liu Shu Xing Xiaobin Li Liwen Han Kechun Liu Tao Wei Mingyang Zhou 《European Journal of Lipid Science and Technology》2021,123(6):2000276
In this study, the anti-atherosclerotic properties of three marine phospholipids (MPLs) extracts from fishery by-products including codfish roe, squid gonad, and shrimp head are verified. Their effects on key factors involved in atherosclerosis are examined and compared to explore whether the differences in their constitutions lead to the differences in the function. All three MPLs dampen oxidation of low- density lipoproteins (LDL) in vitro. Treating RAW264.7 macrophages and HUVECs endothelial cells with each MPLs ranging 10–100 µg mL−1 does not decrease cell viability, yet ox-LDL caused cytotoxicity of both cells are alleviated by 50 or 100 µg mL−1 MPLs treatment. In addition, the three MPLs reduce ox-LDL induced macrophage foam-like transition, mainly through inhibition of lipid uptake. Of the three MPLs, the one from squid gonad exhibits the best effect. On the other hand, all three MPLs modulate inflammatory responses, equally, by inhibiting the adhesion of monocytes to endothelial cells, and decreasing secretion of pro-inflammatory cytokines IL-6 and MCP-1. Using a high-cholesterol diet induced zebrafish model, it is found that all three MPLs, especially the one from squid gonad, alleviates cholesterol accumulation in early plaques, and decreases total cholesterol as well as lipid peroxide in vivo. Practical Applications: As a way of making the best of the increasingly scarce marine resources, valuable lipid components can be recovered from by-products and wastes from the fishery industry. Here, we tested the anti-atherosclerotic effects and the mechanisms of three MPLs extracted from codfish roe, squid gonad, and shrimp head. Our study provides further evidence that marine phospholipids extracted from fishery by-products could protect against atherosclerosis, and helps to elucidate the structure-function relationship of MPLs. 相似文献
2.
Siqi Yu Qin Wang Jianwei Wang Yong Xiang Xiaobin Niu Tingshuai Li 《International Journal of Hydrogen Energy》2021,46(27):14331-14337
Artificial nitrogen fixation is emerging as a promising approach for synthesis of ammonia at mild conditions. Inspired by biological nitrogen fixation based on bacteria containing iron, zinc doped Fe2O3 nanoparticles are proposed as an efficient and earth abundant electrocatalyst for converting N2 to NH3. In neutral media, it achieves a maximum Faradaic efficiency (FE) of 10.4% and a large NH3 yield rate of 15.1 μg h?1 mg?1cat. at ?0.5 V vs. reversible hydrogen electrode. This catalyst also exhibits excellent selectivity and stability. Theoretical calculations suggest the reaction follows the associative enzymatic mechanism and it has a barrier of as low as 0.68 eV. 相似文献
3.
A novel series of temperature‐sensitive poly[(N‐isopropylacrylamide)‐co‐(ethyl methacrylate)] (p(NIPAM‐co‐EMA)) microgels was prepared by the surfactant‐free radical polymerization of N‐isopropylacrylamide (NIPAM) with ethyl methacrylate (EMA). The shape, size dispersity and volume‐phase transition behavior of the microgels were investigated by transmission electron microscopy (TEM), ultraviolet–visible (UV–Vis) spectroscopy, dynamic light scattering (DLS) and differential scanning calorimetry (DSC). The transmission electron micrographs and DLS results showed that microgels with narrow distributions were prepared. It was shown from UV–Vis, DLS and DSC measurements that the volume‐phase transition temperature (VPTT) of the p(NIPAM‐co‐EMA) microgels decreased with increasing incorporation of EMA, but the temperature‐sensitivity was impaired when more EMA was incorporated, causing the volume‐phase transition of the microgels to become more continuous. It is noteworthy that incorporation of moderate amounts of EMA could not only lower the VPTT but also enhance the temperature‐sensitivity of the microgels. The reason for this phenomenon could be attributed to changes in the complicated interactions between the various molecules. Copyright © 2004 Society of Chemical Industry 相似文献
4.
纳米碳管的电子衍射及其螺旋度测量 总被引:1,自引:0,他引:1
本文对电弧放电和催化剂热解碳氢气法制备的多层直形纳米碳管的倒空间及其螺旋度,采用电子衍射进行了研究。结果表明:尽管制备方法不同,两类多层管的结构相似,皆由螺旋和非螺旋的单层石墨管组成;对其倒空间的分析以及系列倾转电子衍射实验证明,衍射图中测得的表观螺旋度值随和射条件而改变,只有在垂直入射条件下该值才代表碳管的真实螺旋度; 相似文献
5.
本文介绍了广播发射台利用计算机技术、网络技术、遥控遥测技术、现代测试手段,对设备进行自动化控制与管理;实现设备技术指标自动测试,发射台无人值班、有人留守,建立机器的计算机档案制度,确保安全优质播出的方法和经验。 相似文献
6.
多用途放射性废物焚烧系统工程验证试验 总被引:7,自引:4,他引:3
对建立的多用途放射性废物焚烧系统,进行了工程验证试验。试验主要包括固体废物(包括树脂)和废油焚烧及烟气净化时系统的性能测定、非放示踪试验、72h连续运行考验等。经过共计500多小时的试验,验证了工艺流程、主要设备结构、仪表测控及系统安全等设计的可行性和可靠性;系统运行平稳,设备及仪表工作正常。本系统可一炉多用,其处理能力、减容系数、焚烧灰中残炭率以及系统总去污系数等指标,均达到了设计要求。 相似文献
7.
8.
Preparation of micro-arc oxidation coatings on magnesium alloy and its thermal shock resistance property 总被引:2,自引:1,他引:2
JIANG Zhaohua ZENG Xiaobin and YAO Zhongping Department of Applied Chemistry Harbin Institute of Technology Harbin China 《稀有金属(英文版)》2006,25(3):270-273
1. Introduction Due to their high specific strength, good electro-magnetic shielding characteristics, high damping characteristics, good cast ability, and excellent pol-ishing capability, magnesium alloys are extensively used in aeronautical, automobile, and electro- communication industries [1-3]. But magnesium has some disadvantages, such as low chemical stability, high negative electric potential, and low hardness, so it is necessary to use surface disposal to accommo-date the demand for re… 相似文献
9.
锌空气电池空气电极催化材料的研究 总被引:3,自引:0,他引:3
采用将Li2CO3,电解二氧化锰(EMD)和Co(NO3)2·6H2O混合进行高温固熔反应的合成方法,制备了1种尖晶石型金属氧化物催化材料LiMn2-xCoxO4。通过电化学测试(极化曲线、放电曲线)、X射线衍射分析(XRD)以及扫描电镜(SEM)等方法对电极的微观结构和性能进行了研究。实验结果表明,以LiMn1.95Co0.05O4为催化材料的气体扩散电极具有最好的综合电化学性能。其0.9V极化电位时的最大电流密度可达210mA/cm2AA型(5号)样品电池以100mA电流恒流放电,容量可高达4439mAh。 相似文献
10.
本文首先建立了模块化多电平换流器(modular multilevel converter,MMC)的时域平均模型.接着,为获取中压应用场景下MMC平均开关函数的谐波特性,建立了平均开关函数的动态相量模型.基于MMC的时域平均模型和平均开关函数动态相量模型,推导得到MMC的直流侧谐波等值电路.等值电路由直流侧等效谐波电流源和等效谐波阻抗组成,其中等效谐波电流源不仅能反映MMC交流侧谐波电流对直流侧谐波电流的传递作用,还能反映直流侧特征谐波电流特性.最后,基于Matlab/Simulink仿真模型验证了MMC直流侧等值电路的正确性. 相似文献