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1.
The changes in polyphenol fractions after in vitro fermentation of apple peel polyphenol (APP) by gut microbiota as well as the effects of APP on the growth, pH value, short-chain fatty acids (SCFAs) production and intestinal flora composition of gut microbiota fermentation were firstly explored in this study. The relative abundance of Lactobacillus in the APP group was 49.55% with an increment of 49.40% compared with the blank group, while that of Bifidobacterium was 13.32%. Moreover, the flora produced 37.093 ± 0.478 mM of SCFAs including acetic acid, propionic acid, butyric acid and valeric acid during the process of fermentation, thus reduced the environmental pH value. In addition, polyphenol fractions in APP were altered by gut microbiota fermentation to some extent, for example, glycosides were hydrolysed to aglycones. These findings suggested APP as a potential prebiotic agent to alleviate the disorder of intestinal flora.  相似文献   
2.
Sensitizing conventional fluorescence (CF) dopants with thermally activated delayed fluorescence (TADF) materials has achieved considerable progress, by which the advantages of TADF materials and CF dopants can be fully harnessed. However, the usually used co-phase configuration of CF dopant-engaged sensitizing systems often encounters exciton loss due to Dexter energy transfer (DET). Herein, an effective out-of-phase configuration is proposed to sensitize CF dopants in the fabrication of white organic light-emitting diodes (WOLEDs). Based on a new efficient sky-blue TADF luminogen DCP-BP-DPAC which has an electroluminescence (EL) peak at 486 nm and an EL efficiency of 26.6%, a green TADF material BDMAC-XT, and a red CF dopant DBP sensitized by BDMAC-XT through an out-of-phase configuration without interlayer, efficient WOLEDs are successfully fabricated. By further adopting orange TBRB or 4CzTPNBu as intermediate sensitizers, more efficient energy transfer to DBP is achieved via Förster energy transfer. Through step-by-step energy transfer and elimination of excess DET process, high-performance all-fluorescent WOLEDs are achieved, providing excellent EL efficiencies over 23.0%, and highly stable white light with a high color rendering index of 87. The outstanding EL performance and high-quality emission color demonstrate the great potential of the proposed out-of-phase design for sensitizing systems of WOLEDs.  相似文献   
3.
  [目的]  利用抽水蓄能电站优化火电厂的出力曲线,是提高电力系统经济性的重要手段。  [方法]  建立了抽水蓄能电站与火电厂联合优化运行的数学模型,然后以某实际电力系统为例对联合运行进行了优化模拟。最后探讨了联合运行节煤的内在机理。  [结果]  模拟结果表明抽水蓄能电站与火电厂联合优化运行降低了系统煤耗。  [结论]  建议要充分利用抽水蓄能电站来优化火电厂的出力曲线,提高电力系统运行经济性。  相似文献   
4.
采用自主研制的在线超低温预浓缩设备,连续在线采集大气样品或者连续采集苏玛罐离线样品,对样品进行超低温捕集浓缩和二次超低温冷冻聚焦,采用全二维气相色谱-飞行时间质谱联用技术分离检测浓缩后的挥发性有机物,实现对大气中C2~C12共100多种挥发性有机物的浓缩富集和定性定量分析。本研究对该方法的线性、重复性、加标回收率、检出限等性能进行表征,并与常规一维气相色谱-四极杆质谱联用系统的定性定量结果进行比较。结果表明,该方法不仅满足大气中挥发性有机物检测的性能指标要求,且组分定性定量的准确性、灵敏度等指标均优于一维气相色谱-四极杆质谱联用技术,在挥发性有机物成分较复杂的大气样品检测中具有明显优势。  相似文献   
5.
苏海波  谭国斌  黄正旭  洪义  车欣欣  王攀攀  高伟  周振 《质谱学报》2020,41(2):153-159,I0006
本研究开发了一台应用于高能量离子束诊断的直线式飞行时间质谱仪,实现了其与高能真空弧放电离子源的联用。该仪器加速电压30 kV,飞行腔有效飞行距离1.5 m,通过短脉冲离子门精确截取,ICCD高速相机优化聚焦,仪器分辨率优于90 FWHM,对放电过程中产生的等离子体可实现不同时间的离子成分分析。将该方法用于真空弧放电离子源放电过程中离子成分的检测,放电2 μs时,电离成分以气态离子C+、O+、C2+、O2+为主;放电6 μs后,除气体成分外,还可以检测到Fe+、Cu+及其同位素金属离子峰。该仪器能够给出离子源放电产生离子的种类、价态以及相对含量等信息,可实现整个放电过程产生离子成分信息的准确诊断。  相似文献   
6.
Greenish yellow organic light-emitting diodes (GYOLEDs) have steadily attracted researcher's attention since they are important to our life. However, their performance significantly lags behind compared with the three primary colors based OLEDs. Herein, for the first time, an ideal host-guest system has been demonstrated to accomplish high-performance phosphorescent GYOLEDs, where the guest concentration is as low as 2%. The GYOLED exhibits a forward-viewing power efficiency of 57.0 lm/W at 1000 cd/m2, which is the highest among GYOLEDs. Besides, extremely low efficiency roll-off and voltages are achieved. The origin of the high performance is unveiled and it is found that the combined mechanisms of host-guest energy transfer and direct exciton formation on the guest are effective to furnish the greenish yellow emission. Then, by dint of this ideal host-guest system, a simplified but high-performance hybrid white OLED (WOLED) has been developed. The WOLED can exhibit an ultrahigh color rendering index (CRI) of 92, a maximum total efficiency of 27.5 lm/W and a low turn-on voltage of 2.5 V (1 cd/m2), unlocking a novel avenue to simultaneously achieve simplified structure, ultrahigh CRI (>90), high efficiency and low voltage.  相似文献   
7.
以玻璃化转变温度较低的共聚酯制备了聚酯热熔胶。研究结果表明:聚酯热熔胶对丙烯腈-丁二烯-苯乙烯共聚物(ABS)、聚碳酸酯(PC)等极性塑料与金属材料具有良好的粘接性能,稳定后的剥离强度大于100N/25mm;同时,具有良好的耐老化性能及粘接持久性。聚酯热熔胶可取代国外产品用于电子行业用极性聚合物与金属材料粘接。  相似文献   
8.
文章介绍了高反光率EVA胶膜的制备过程,并将其与常规EVA胶膜以及双玻组件用EVA胶膜进行封装组件功率及黄色指数变化效果对比分析。研究结果表明:采用高反射功能助剂改性方法制备的高反光率EVA胶膜,具有优异抗紫外辐射老化能力,同时能够提高组件的光电转换效率及功率。  相似文献   
9.
Aldehyde dehydrogenase 1 (ALDH1) is reported as a biomarker for identifying some cancer stem cells, and down-regulation or inhibition of the enzyme can be effective in anti-drug resistance and a potent therapeutic for some tumours. In this paper, the inhibitory activity, mechanism mode, molecular docking and 3D-QSAR (three-dimensional quantitative structure activity relationship) of curcumin analogues (CAs) against ALDH1 were studied. Results demonstrated that curcumin and CAs possessed potent inhibitory activity against ALDH1, and the CAs compound with ortho di-hydroxyl groups showed the most potent inhibitory activity. This study indicates that CAs may represent a new class of ALDH1 inhibitor.  相似文献   
10.
费用编码体系是电网工程造价数据规范中的重要组成部分。以南网公司的工程造价数据规范为例,针对费用编码体系的应用现状、存在问题以及信息化发展趋势进行梳理分析,提出现有电网工程造价数据规范费用编码体系的改进方案。通过案例验证该费用编码体系的可行性,从而为电网工程造价数据规范费用编码体系的标准化构建提供借鉴,以利于工程造价信息的交流与共享,促进编码体系的深入推广应用。  相似文献   
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