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31.
Mi Ouyang Dacheng Dai Xuming Hu Yuwen Li Zhangxin Chen Bowen Tao Lina Zhang Weijun Li Yujie Dong Ru Bai Xiaojing Lv Cheng Zhang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(15):2269-2279
A new star-shaped structure conjugated microporous polymers, poly (2,8,14-tri[4-diphenyl-benzene]-hexaazatrinaphthylene) (PTPA-HATN), was designed and in-situ electrochemically polymerized on the surfaces of FTO electrodes with a directional alignment TiO2 nanorod array to obtain TiO2/PTPA-HATN core-shell nanocomposite films. Compared with the PTPA-HATN film, the TiO2/PTPA-HATN composite film exhibits higher optical contrast and faster response time, with contrast of 57% at 783 nm, coloring time of 3.62 s and discoloring time of 2.55 s (43%, 4.63 s and 4.77 s for PTPA-HATN film, respectively). After 400 cycles, the contrast of nanocomposite film decreased by 28%, while the PTPA-HATN film basically lost its electrochromic properties. A simple three-layer EC prototype device based on TiO2/PTPA-HATN nanocomposite film constructed with hydrogel electrolyte clearly shows color changes at different voltages. On the one hand, the formation of core-shell porous nanostructure of TiO2/PTPA-HATN composite film provides a larger ion doping/de-doping interface, shortening the average diffusion length of ions. On the other hand, the large indented polymer-nanorods contact interface makes it difficult for the polymer to detach from the electrode, thus significantly improving the cyclic stability of the composite film. 相似文献
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烟草特性及吸烟的危害 总被引:2,自引:1,他引:1
烟草是一种化学成分极为复杂的植物,烟碱是烟草的特征性物质。烟草在燃吸过程中,会发生复杂的化学反应,从而产生含有数千种化学物质的烟气。其中对人体健康最为有害的物质有:焦油、烟碱,一氧化碳、醛类等。这些有害物质进入人体会导致呼吸道、消化系统、心血管系统的疾病及各种癌症。对青少年身体健康造成的危害更大。统计数字表明,由吸烟致病的死亡率相当高。人们应根除吸烟这种不良嗜好。 相似文献
34.
目前处于设计阶段的哈尔滨工业大学空间辐照效应装置,其核心部件是由1台10 MeV的注入器、1台300MeV的同步加速器以及输运线构成的加速器装置。同步加速器中引出的质子束流被用于辐照研究。基于装置的概念设计,优化了其同步加速器部分的设计。设计了新的磁聚焦结构,优化了基于新的磁聚焦结构的多圈注入系统的凸轨变化模式,提高了注入效率。为了更好地优化引出束流的时间结构,慢引出系统采用了RF knock-out的方法。为了满足精准辐照的要求,研究了RF Kicker的频率调制,发现RF Kicker的双频调制能使得引出束流更均匀。A research complex for aerospace radiation effects research is in the designing stage in Harbin Institute of Technology. Its core part is a proton accelerator complex, which consists of a 10 MeV injector, a 300 MeV synchrotron and beam transport lines. The proton beam extracted from the synchrotron is utilized for the radiation effects research. Based on the conceptual design, the design study for optimizing the synchrotron has been done. A new lattice design was worked out, and the decreasing pattern of the bump of the multi-turn injection system was optimized to increase the injection efficiency. In order to improve the time structure of the extracted beam, a RF knock-out method is employed in the slow extraction system. To meet the requirement of accurate control of dose, the frequency modulation of the RF kicker is well investigated, and the dual frequency modulation has been found to have a better performance for a uniform spill. 相似文献
35.
Partial oxidation of simulated hot coke oven gas to syngas over Ru-Ni/Mg(Al)O catalyst in a ceramic membrane reactor
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Hydrogen amplification from simulated hot coke oven gas (HCOG) was investigated in a BaCo0.7Fe0.2Nb0.1O3−δ (BCFNO) membrane reactor
combined with a Ru-Ni/Mg(Al)O catalyst by the partial oxidation of hydrocarbon compounds under atmospheric pressure. Under optimized
reaction conditions, the dense oxygen permeable membrane had an oxygen permeation flux around 13.3 ml/(cm2·min). By reforming of the
toluene and methane, the amount of H2 in the reaction effluent gas was about 2 times more than that of original H2 in simulated HCOG. The
Ru-Ni/Mg(Al)O catalyst used in the membrane reactor possessed good catalytic activity and resistance to coking. After the activity test, a small
amount of whisker carbon was observed on the used catalyst, and most of them could be removed in the hydrogen-rich atmosphere, implying
that the carbon deposition formed on the catalyst might be a reversible process. 相似文献
36.
卫星钟差确定受限于经典测量的散粒噪声极限,钟差测量精度仅为ns量级。基于军民领域对高精度时间基准的迫切需求,提出了一种基于双路六延迟传送带量子纠缠光的卫星钟差测量方案,并且该方案以传送带协议为基础。首先,通过自发参量下转换制备了频率纠缠光信号。然后,利用HOM (Hong-Ou-Mandel)干涉仪对频率纠缠光信号进行了二阶关联检测解算,进而得到了钟差信息。最后,仿真分析了相关参数对钟差测量的影响。所提方案无需进行到达时间测量,不受色散效应及星地距离的影响,在理论上可以实现ps量级的卫星钟差测量。 相似文献
37.
为提高电池的光电转换效率,通过改善激光刻蚀工艺,采用355 nm紫外纳秒激光分别进行了ZnO:Al薄膜(AZO)刻蚀(P1)、非晶硅薄膜(-Si)刻蚀(P2)和背电极刻蚀(P3)研究。采用万用表测量P1隔离电阻,采用电子扫描显微镜(SEM)和三维激光扫描仪测量刻槽的微结构和三维成像,激光拉曼散射光谱检测非晶硅薄膜刻蚀边缘的晶化。实验结果表明,当刻蚀速度600 mm/s,重复频率40 kHz,功率1.74 W的紫外激光刻蚀ZnO:Al薄膜时,刻槽的隔离效果最佳,达20 M; 紫外激光刻蚀能够有效地减小激光热效应引起的热影响和刻槽边缘的晶化范围,提高非晶硅薄膜电池的性能。 相似文献
38.
带有高压储液器的制冷系统建模研究 总被引:1,自引:1,他引:0
通过对制冷系统循环特性、变工况特性和参数间耦合特性的分析,遵循热力学基本定律和能量、动量、质量守恒定律,采用稳态和动态建模相结合的方法建立压缩式制冷系统的数学模型。针对换热器建模难点采用分相区和移动边界相结合的方法建立其集总参数动态模型,并且冷凝器与高压储液器相结合,构成冷凝器加储液器的整体部件,文中建立的制冷系统的整体模型,反映了制冷系统工况变化时制冷剂质量的重新分配及其对状态变量的影响,提高了系统建模的精度,最后通过实验对所建模型的准确性进行了验证。 相似文献
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40.
Liu X Zhao X Wang X Zhang J Huang Y Mo Q Qian K Zhu Y 《Photochemistry and photobiology》2012,88(5):1287-1292
Photochemical virus inactivation technology is widely used to improve the safety of blood products. However, the process by which this inactivation occurs and the resulting immunogenicity of treated viruses remain to be elucidated. This study aimed to explore the effects of two photochemical inactivation methods (methylene and riboflavin, MP and RP) on hepatitis B virus (HBV) immunogenicity. Inactivated HBV were incubated with PBMC from six healthy donors. Culture supernatants were collected at 0, 24 and 72 h for the analysis of HBsAg and HBeAg expression using ELISA. Cytokine expression was analyzed at 72 h using ELISA. Costimulatory and cell adhesion molecule mRNA expression was analyzed at 24 h by RT–PCR. No significant changes in HBsAg and HBeAg were detected following MP. However, the secretion of TNF‐α and IFN‐γ was upregulated. Expression of CD80, CD86, ICAM2 and LFA3 mRNA was also upregulated. In contrast, although RP did not significantly alter HBsAg expression, a reduction in HBeAg expression was observed. Furthermore, no upregulation of cytokines and intracellular molecule expression was observed following RP. These data indicate that the immunogenicity of HBV is retained following MP, and the inactivation of HBV could upregulate the Th1‐type cellular immune responses, which may play significant roles in the antiviral process. 相似文献