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排序方式: 共有207条查询结果,搜索用时 15 毫秒
31.
Polyethylene glycol (PEG) is an important and popular phase change material (PCM), but is not a good antistatic material, which would cause the accumulation of static electricity and electrostatic discharge when used for the thermal energy storage and thermal management of electrical devices. Herein, we prepared a PEG-based solid–solid PCM (SSPCM) with good antistatic property by introducing an ionic liquid onto the macromolecular chains. This SSPCM is in solid state even at 90°C, avoiding the leakage issue of pure PEG. Its latent heat values in the melting and solidifying processes are 56.2 and 30.6 J g−1, respectively. Additionally, this SSPCM has good thermal stability and thermal reliability for thermal storage and thermal management according to thermogravimetric and thermal cycling tests. The volume- and surface resistivity of the SSPCM at ambient temperature are 108.87 Ω m and 108.92 Ω, respectively, showing good antistatic performance. 相似文献
32.
Jieni Li Henan Li Lai Liu Huizhen Yao Bingbing Tian Chenliang Su Haizhe Zhong Ye Wang Lifu Zhang Yumeng Shi 《化学:亚洲杂志》2019,14(16):2861-2868
Organometallic halide perovskites have attracted great research interest as light‐active materials for use in optoelectronics. Here, we report a high‐performance photoconductor based on a methylammonium lead iodide (MAPbI3) film that was prepared from a methylamine‐treated MAPbI3/PbI2 perovskite film. An ultrahigh responsivity of 3.6 A W?1 and detectivity of 5.4×1012 Jones were obtained for the film under 0.5 mW cm?2 white‐light illumination. In addition, under 420 nm light irradiation, the film exhibited its highest responsivity and detectivity of 30 A W?1 and 2.4×1014 Jones, respectively. The excellent photo‐response performance results from the improved electronic quality and suppressed nonradiative recombination channels of the treated perovskite thin film. 相似文献
33.
Ning Wang Yumeng Hao Xiaowei Feng Haidan Zhu Dazhi Zhang Ting Wang Xiaoyan Cui 《中国化学快报》2022,33(1):133-140
As an essential part in the toolbox of super-resolution microscopy, stimulated emission depletion(STED)nanoscopy has been widely explored in revealing the substructure and bioactivities in fluorescence imaging. Among the applied STED fluorophores, silicon-substituted rhodamines(SiRs) belong to one of the most extensively employed fluorophores. The carboxy-SiR was favored in STED bioimaging with many advantages, including reliable photostability, cell permeability, tunable fluorogenicity, feasibl... 相似文献
34.
This work deals with numerical solution of transonic flow in turbine cascades. We compare results achieved by SST, TNT and EARSM turbulence models and we also present results achieved by two equations turbulence model with an algebraic bypass transition model. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
35.
36.
Ben Li Yumeng Ji Chenlong Yi Xufeng Wang Chaoyang Liu Chufan Wang Xiaohu Lu Xiaohan Xu Xiaowei Wang 《Molecules (Basel, Switzerland)》2022,27(13)
Atherosclerosis (AS) is one of the leading causes of death among the elderly, and is primarily caused by foam cell generation and macrophage inflammation. Rutin is an anti-inflammatory, anti-oxidant, anti-allergic, and antiviral flavonoid molecule, known to have anti-atherosclerotic and autophagy-inducing properties, but its biological mechanism remains poorly understood. In this study, we uncovered that rutin could suppress the generation of inflammatory factors and reactive oxygen species (ROS) in ox-LDL-induced M2 macrophages and enhance their polarization. Moreover, rutin could decrease foam cell production, as shown by oil red O staining. In addition, rutin could increase the number of autophagosomes and the LC3II/I ratio, while lowering p62 expression. Furthermore, rutin could significantly inhibit the PI3K/ATK signaling pathway. In summary, rutin inhibits ox-LDL-mediated macrophage inflammation and foam cell formation by inducing autophagy and modulating PI3K/ATK signaling, showing potential in treating atherosclerosis. 相似文献
37.
Tingjunhong Ni Zichao Ding Fei Xie Yumeng Hao Junhe Bao Jingxiang Zhang Shichong Yu Yuanying Jiang Dazhi Zhang 《Molecules (Basel, Switzerland)》2022,27(11)
A series of triazole derivatives containing phenylethynyl pyrazole moiety as side chain were designed, synthesized, and most of them exhibited good in vitro antifungal activities. Especially, compounds 5k and 6c showed excellent in vitro activities against C. albicans (MIC = 0.125, 0.0625 μg/mL), C. neoformans (MIC = 0.125, 0.0625 μg/mL), and A. fumigatus (MIC = 8.0, 4.0 μg/mL). Compound 6c also exerted superior activity to compound 5k and fluconazole in inhibiting hyphae growth of C. albicans and inhibiting drug-resistant strains of C. albicans, and it could reduce fungal burdens in mice kidney at a dosage of 1.0 mg/kg. An in vivo efficacy evaluation indicated that 6c could effectively protect mice models from C. albicans infection at doses of 0.5, 1.0, and 2.0 mg/kg. These results suggested that compound 6c deserves further investigation. 相似文献
38.
The nickel-base alloy is one of the leading candidate materials for generation IV nuclear reactor pressure vessel.To evaluate its stability of helium damage and retention,helium ions with different energy of 80 keV and 180 keV were introduced by ion implantation to a certain dose(peak displacement damage 1-10 dpa).Then thermal desorption spectroscopy(TDS)of helium atoms was performed to discuss the helium desorption characteristic and trapping sites.The desorption peaks shift to a lower temperature with increasing dpa for both 80 keV and 180 keV irradiation,reflecting the reduced diffusion activation energy and faster diffusion within the alloy.The main release peak temperature of 180 keV helium injection is relatively higher than that of 80 keV at the same influence,which is because the irradiation damage of 180 keV,helium formation and entrapment occur deeper.The broadening of the spectra corresponds to different helium trapping sites(He-vacancies,grain boundary)and desorption mechanisms(different Hen Vm size).The helium retention amount of 80 keV is lower than that of 180 keV,and a saturation limit associated with the irradiation of 80 keV has been reached.The relatively low helium retention proves the better resistance to helium bubbles formation and helium brittleness. 相似文献
39.
Résumé On a mis au point une méthode d'analyse par activation neutronique du lanthane et de l'or en quantités inférieures au ppm
dans l'acier, sans détermination du rendement chimique. La méthode consiste à isoler quantitativement les activités de La
et d' Au par des procédés d'échange d'ions et à faire ensuite une spectrométrie NaI(T1). La limite de détection est abaissée
jusqu'à 10 et 5 ppb pour La et Au respectivement. Il n'y a pratiquement pas d'interférence avec les autres éléments habituellement
présent dans l'acier.
相似文献
40.
Ma?gorzata Barańska Katarzyna Chruszcz Mateusz Fo?ciak 《Journal of Molecular Structure》2003,658(3):229-239
In this work the vibrational analysis of (hydroxypyridin-3-yl-methyl)phosphonic acid (MC5) is presented using both experimental and theoretical methods. FT-IR spectra of the solid state MC5 precipitated at certain pH values in which consecutive deprotonations of this ligand occurs were recorded. Thus, we were able to measure IR spectra of cationic, two anionic and zwitterion forms of MC5. Additionally, the geometry optimization and vibrational frequencies were performed at the B3PW91 level with the 6-31G** basis set for each species. As was shown, FT-IR spectra could be fairly good reproduced by a theoretical method applied here. Additionally, charge distributions and aromaticity index were calculated for discussed MC5 forms by using generalized atomic polar tensor and harmonic oscillator model of aromaticity, respectively. 相似文献