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81.
Wei Lv Chun Wang Xing-Chi Lin Xiao-Fei Mei Wen Wang E Yang Qi-Dan Ling Zheng-Huan Lin 《高分子科学》2021,39(9):1177-1184
Solid-stated smart polymers responsive to external stimuli have attracted much attention for potential application in the field of photoelectron devices, logic gates, sensor, data storage and security. However, it is a bigger challenge for polymers than that for small molecules in solid state to acquire stimuli-responsive properties, because polymers with high molecular weight are not as easy to change the packing structure as small molecules under external stimulation. Here, a D-A type alternating copolymer PTMF-o containing 3,4-bisthienylmaleimide(A unit) and fluorene(D unit) is designed and synthesized. Upon irradiation of sunlight, PTMF-o film exhibits a photo-response with the color altering from purple to colorless. It is attributed to the structure of copolymer transformed from ring-opening form(PTMF-o) to ring-closure form(PTMF-c), resulting from the oxidative photocyclization of 3,4-bisthienylmaleimide unit. Consequently, the ability of charge transfer(CT) from fluorene to 3,4-bisthienylmaleimide unit in PTMF-o can be easily weakened by light stimuli. PTMF-o film displays a WORM-type resistive storage performance for the strong CT. Interestingly, after exposure, the electrical memory behavior in situ transfers into FLASH type, due to weak CT in PTMF-c. PTMF-o film can also be employed as smart material to construct NAND and NOR logic gates by using light as input condition. The work provides a simple way to modify the electronic properties of polymers and realize stimuli-response in solid states. 相似文献
82.
In this work, an analytical model of gate-engineered junctionless surrounding gate MOSFET (JLSRG) has been proposed to uncover its potential benefit to suppress short-channel effects (SCEs). Analytical modelling of centre potential for gate-engineered JLSRG devices has been developed using parabolic approximation method. From the developed centre potential, the parameters like threshold voltage, surface potential, Electric Field, Drain-induced Barrier Lowering (DIBL) and subthershold swing are determined. A nice agreement between the results obtained from the model and TCAD simulation demonstrates the validity and correctness of the model. A comparative study of the efficacy to suppress SCEs for Dual-Material (DM) and Single-Material (SM) junctionless surrounding gate MOSFET of the same dimensions has also been carried out. Result indicates that TM-JLSRG devices offer a noticeable enhancement in the efficacy to suppress SCEs by as compared to SM-JLSRG and DM-JLSRG device structures. The effect of different length ratios of three channel regions related to three different gate materials of TM-JLSRG structure on the SCEs have also been discussed. As a result, we demonstrate that TM-JLSRG device can be considered as a competitive contender to the deep-submicron mainstream MOSFETs for low-power VLSI applications. 相似文献
83.
Intrinsic Flexibility of the Zeolitic Imidazolate Framework ZIF‐7 Unveiled by CO2 Adsorption and Hg Intrusion 下载免费PDF全文
Dr. Marc Pera‐Titus 《Chemphyschem》2014,15(8):1581-1586
ZIF‐7, built as an assembly of ZnII centers and benzimidazolate ligands, shows prominent S‐shaped isotherms upon CO2 adsorption that can be attributed to sorbate‐induced gate‐opening phenomena involving a narrow‐to‐large pore phase transition. This peculiar sorption pattern can be captured via the formulation of thermodynamic isotherms, providing a direct enthalpic and entropic view of the gate‐opening process. Relying on such an approach, an energy barrier with preferential enthalpic nature for CO2 adsorption/desorption in the gate‐opening region could be unveiled. Moreover, the elastic energy involved during the gate‐opening process was revisited to 1.4–2.8 kJ mol?1 of solid in the temperature range 273–323 K, matching the value measured by isostatic compression of a ZIF‐7_lp sample filled with DMF and showing a dominant entropic contribution. 相似文献
84.
Yidan Liu Yizhong Yuan Xiaohui Tian Jinyu Sun 《International journal of quantum chemistry》2020,120(23):e26399
Nowadays, blue fluorescent organic light-emitting diodes (FOLEDs) have attracted considerable attention from both academia and industry. According to spin statistics, electrical excitation results in the formation of ∼25% singlet excitons and ∼75% triplet excitons (signifying ~75% energy loss), which triggered wide-ranging efforts to harvest as many triplet excitons as possible. The materials that can convert triplet excitons into singlet excitons from the high-lying excited triplet states (referred as “hot exciton” channel) to realize high efficiency were reported, which can also efficaciously avoid the accumulation of triplet excitons in T1 state. In this study, by means of density functional theory (DFT) and time-dependent DFT, we have theoretically investigated the electronic and photophysical properties of 16 newly designed molecules with donor-bridge-acceptor framework to search for the blue FOLED materials exploiting the “hot exciton” path. Important properties, such as singlet-triplet energy gaps, absorption and emission parameters, and reverse intersystem crossing rates (kRISC), of five target molecules were studied. The calculated results demonstrate that thiophene-diphenylamine (kRISC up to 1.03 × 108 seconds−1) may have promising potential as blue FOLED materials by virtue of the “hot exciton” effect. 相似文献
85.
86.
可控/“活性”自由基聚合(CLRP)可以用于制备分子量分布窄、分子链缺陷少的聚合物,如聚乙烯(PE)、聚氯乙烯(PVC)、聚偏氯乙烯(PVDC)和聚偏氟乙烯(PVDF),且易控制上述单体与其他单体共聚得到嵌段聚合物。本文调研了近年来可控/“活性”自由基聚合(如碘转移聚合(ITP)、氮氧稳定自由基聚合(NMP)、可逆加成断裂链转移(RAFT)聚合和金属催化的活性自由基聚合(OMRP)等)制备聚乙烯和聚卤代烯烃等方面的工作,并指出了未来的发展方向。 相似文献
87.
Marco Deiana Karam Chand Jan Jamroskovic Ikenna Obi Erik Chorell Nasim Sabouri 《Angewandte Chemie (International ed. in English)》2020,59(2):896-902
The design of turn‐on dyes with optical signals sensitive to the formation of supramolecular structures provides fascinating and underexplored opportunities for G‐quadruplex (G4) DNA detection and characterization. Here, we show a new switching mechanism that relies on the recognition‐driven disaggregation (on‐signal) of an ultrabright coumarin‐quinazoline conjugate. The synthesized probe selectively lights‐up parallel G4 DNA structures via the disassembly of its supramolecular state, demonstrating outputs that are easily integrable into a label‐free molecular logic system. Finally, our molecule preferentially stains the G4‐rich nucleoli of cancer cells. 相似文献
88.
Jinyi Dong Meng Wang Yihao Zhou Chao Zhou Qiangbin Wang 《Angewandte Chemie (International ed. in English)》2020,59(35):15038-15042
Self‐assembled plasmonic logic gates that read DNA molecules as input and return plasmonic chiroptical signals as outputs are reported. Such logic gates are achieved on a DNA‐based platform that logically regulate the conformation of a chiral plasmonic nanostructure, upon specific input DNA strands and internal computing units. With systematical designs, a complete set of Boolean logical gates are realized. Intriguingly, the logic gates could be endowed with adaptiveness, so they can autonomously alter their logics when the environment changes. As a demonstration, a logic gate that performs AND function at body temperature while OR function at cold storage temperature is constructed. In addition, the plasmonic chiroptical output has three distinctive states, which makes a three‐state molecular logic gate readily achievable on this platform. Such DNA‐based plasmonic logic gates are envisioned to execute more complex tasks giving these unique characteristics. 相似文献
89.
In the fields of biocomputing and biomolecular, DNA molecules are applicable to be regarded as data of logical computing platform that uses elaborate logic gates to perform a variety of tasks. Graphene oxide (GO) is a type of novel nanomaterial, which brings new research focus to materials science and biosensors due to its special selectivity and excellent quenching ability. G-quadruplex as a unique DNA structure stimulates the intelligent application of DNA assembly on the strength of its exceptional binding activity. In this paper, we report a universal logic device assisted with GO and G-quadruplex under an enzyme-free condition. Integrated with the quenching ability of GO to the TAMRA (fluorophore, Carboxytetramethylrhodamine) and the enhancement of fluorescence intensity produced by the peculiar binding of G-quadruplex to the NMM (N-methylmesoporphyrin IX), a series of basic binary logic gates (AND. OR. INHIBIT. XOR) have been designed and verified through biological experiments. Given the modularity and programmability of this strategy, two advanced logic gates (half adder and half subtractor) were realized on the basis of the same work platform. The fluorescence signals generated from different input combinations possessed satisfactory results, which provided proof of feasibility. We believe that the proposed universal logical platform that operates at the nanoscale is expected to be utilized for future applications in molecular computing as well as disease diagnosis. 相似文献
90.
提出了一个实现两离子量子逻辑门的简单方案。本方案使用了两个囚禁于线性阱的三能级离子。本方案不使用振动模作为数据总线,仅需要激光与离子的单个相互作用,因而相互作用时间变短,这点从退相干的角度看是很重要的,而且本方案对振动模的加热不敏感。 相似文献