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In this study, two structural isomers α‐PBT and β‐PBT, which only differ in the phenyl substituent position on the quinoline chromophore, have been designed and successfully synthesized. The influences of substituent position on the film morphology and the storage performance of the devices were investigated. Both molecules employed in the memory devices exhibited same nonvolatile binary (write‐once‐read‐many‐times; WORM) characteristics, but the switch threshold voltage (Vth) of the β‐PBT‐based device was clearly lower than that of the α‐PBT‐based device. Simulation results demonstrate that the variation of the phenyl substituent position led to different intermolecular stacking styles and thus to varied grain sizes for each film morphology. This work illustrates that altering the phenyl substituent position on the molecular backbone could improve the quality of the film morphology and reduce power consumption, which is good for the rational design of future advanced organic memory devices (OMDs).  相似文献   
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Zhang  Wen  Liu  Yang  Song  Dengpeng  Guo  Heng  Hu  Jinbang  Wang  Yunli  Xu  Weilin 《Cellulose (London, England)》2021,28(9):5911-5922
Cellulose - Traditional cotton fiber dyeing requires an abundance of salt, which leads to environmental pollution. Consequently, decreasing or eliminating the use of salt has become the primary...  相似文献   
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Qin  Shun-Shun  Liu  Jing-Long  Hu  Feng  Jia  Ai-Quan  Xu  Chao  Zhang  Qian-Feng 《Journal of Cluster Science》2021,32(6):1593-1599
Journal of Cluster Science - Interaction of [Pb(SiPr)2]n with 1.5 equiv. of AgNO3 in DMF under aerobic conditions at room temperature gave a cationic lead-centered thiolate cluster...  相似文献   
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Structural Chemistry - Applying a theoretical approach that combines an efficient and fast global optimization based on genetic algorithms (GA) to search in structure space and the parameterized...  相似文献   
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A nanocomposite of polyaniline/reduced graphene oxide (PANI-rGO) was synthesized using a hydrothermal method. The product was characterized by FT-IR, Raman spectra, XRD, SEM and TEM. Then the hybrid material of PANI-rGO and Nafion (PANI-rGO-NF) was prepared and used to modify glassy carbon electrode for the trace determination of dopamine (DA) employing differential pulse voltammetry (DPV). It was found that the hybrid material showed good catalytic activity toward the oxidation of DA, and no response to ascorbic acid (AA) and uric acid (UA) was observed, suggesting a high selectivity of the sensor toward DA. The peak currents were linearly correlated with the concentration of DA in the range from 0.05 μmol/L to 60.0 μmol/L (R=0.996) and 60.0 μmol/L to 180.0 μmol/L (R=0.996) with a detection limit of 0.024 μmol/L (S/N=3). The modified electrode also exhibited excellent repeatability and stability.  相似文献   
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Engineering near-infrared (NIR) light-sensitive enzymes remains a huge challenge. A photothermal effect-associated method is developed for tailoring the enzymatic activity of enzymes by exposure to NIR light. An ultrasmall platinum nanoparticle was anchored in an enzyme to generate local heating upon NIR irradiation, which enhanced the enzyme activity without increasing bulk temperature. Following NIR irradiation, the enzyme activity was tailored rapidly and reversibly, and was modulated by varying laser power density and irradiation time. Four enzymes were engineered, including glucoamylase, glucose oxidase, catalase, and proteinase K with NIR-light sensitivity, and demonstrated their utility in practical applications such as photolithography and NIR light-responsive antibacterial or anticancer actions. Our investigation suggests that this approach could be broadly used to engineer enzymes with NIR-light sensitivity for many biological applications.  相似文献   
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In order to investigate the effects of non-thermal plasma (NTP) on diesel particulate matter (PM), an engine test bench was built up. An engine exhaust particle sizer (EEPS) was introduced to analyze the emission concentration and size distribution of PM and a thermo-gravimetric analyzer was used to analyze the effects of NTP on the composition of the particulate matter in the exhaust gas. The results show that the size distribution interval of the particle mass concentration falls behind that of the quantity concentration under various loads. When the diesel engine operating speed is 2400 rpm and the load is 25%, after NTP, the proportions of the nucleation mode particles and the accumulative mode particles exhibit a small fluctuation while the proportion of ultrafine particles decreases by 10% due to their large quantity concentration. Under the dual effect of DPF and NTP, the particle quantity concentration decreases by 98%. In order to investigate the effect of NTP on the composition of the PM, a thermo-gravimetric analysis of the particles obtained before and after NTP was carried out. The results show that the proportion of volatile matter falls by 16.05% and solid carbon accounts for an increase of 7.29%. NTP has the ability to improve reduction activity of particles and make particles easier to be oxidized at a lower temperature.  相似文献   
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Plasma Chemistry and Plasma Processing - In this paper, the electron density in radio frequency (RF) hollow cathode discharge (HCD) is investigated in experiments and in simulation based on...  相似文献   
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