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1.
可再生清洁能源的开发和利用对人类社会的可持续发展具有重要意义。 基于动电效应的纳米孔道能量转换系统将流体机械能转化为电能,有望应用于微型电源部件、自驱动纳米机器、微机电体系等领域,为清洁能源发电系统的开发提供了全新的选择。 纳米孔道中的机械能-电能转换过程涉及固体孔道与流体界面间的相互作用,合理设计孔道界面的微观结构,对其进行化学修饰及探讨界面间的相互作用,是提高能量转换效率和输出功率的关键。 近年来,随着纳米技术的迅猛发展及人们对界面物理化学的深入研究,纳米孔道结构和纳流体发电体系能被更精准地设计和集成。 本文主要介绍了基于动电效应的纳米孔道能量转换系统的基本概念,重点关注了纳米孔道中动电效应的最新研究进展,并对该领域进行了展望,为纳米孔道动电效应能量转换系统、纳米发电机、自驱动纳米机器、可穿戴器件等领域的进一步发展和应用提供参考。 相似文献
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Gadusol shows one of the simplest structures among a series of natural UV-absorbing compounds that have been related to the photoprotective and antioxidant functions in aquatic organisms. CASPT2//CASSCF methodology was used to carry out a theoretical study on this basic structure in order to describe the underlying features responsible for the photoprotective capacity of the molecule. The influence of the enol–enolate equilibrium on the photophysical properties was explored. The results confirm that both forms undergo a rapid deactivation, which very efficiently dissipates light energy as heat. This work highlights the potential of molecular-level studies to provide an understanding of natural photoprotective mechanisms and gives support to the future design of structurally related new synthetic sunscreens. 相似文献
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Dario Delgado 《Chemphyschem》2019,20(15):1908-1911
The purpose of this research idea is to develop a method to electrochemically convert carbon dioxide into higher alcohol chains such as ethanol to be used as fuel. Electrochemical CO2 reduction has low yields and poor product selectivity, being able to improve this reaction would have an impact in the energy and food market. We propose the use of a modified nanofluidic transistor to block reaction steps that are thermodynamically favored by constraining the kinetics of the reaction when the reaction takes place in a geometrically restricted environment with different double layer properties to those found in conventional planar electrosynthesis. 相似文献
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Grilj J Laricheva EN Olivucci M Vauthey E 《Angewandte Chemie (International ed. in English)》2011,50(19):4496-4498
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Photoferroelectrics belong to a unique material family that exhibits both photovoltaic and ferroelectric effects simultaneously. The photovoltaic effect is the only known direct method of converting light into electricity and is the basis of solar cells. The ferroelectric effect can induce piezoelectric and pyroelectric effects, which are the working principles of widely used kinetic and thermal sensors, transducers, actuators, and energy harvesters. For a long time, photoferroelectric research was restricted to theoretical investigations only because of either the wide band gap (Eg), which is not able to effectively absorb visible light, or to the weak ferroelectricity caused by a narrow Eg. Recent scientific breakthroughs, however, have opened doors for the development of practical applications. In this article, emerging concepts of creating balanced photovoltaic and ferroelectric properties for photoferroelectrics, as well as those of novel applications in future devices, are presented. 相似文献
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Dr. Samer Gozem Dr. Ekaterina Mirzakulova Dr. Igor Schapiro Dr. Federico Melaccio Prof. Dr. Ksenija D. Glusac Prof. Dr. Massimo Olivucci 《Angewandte Chemie (International ed. in English)》2014,53(37):9870-9875
The photophysics of flavins is highly dependent on their environment. For example, 4a‐hydroxy flavins display weak fluorescence in solution, but exhibit strong fluorescence when bound to a protein. To understand this behavior, we performed temperature‐dependent fluorescent studies on an N(5)‐alkylated 4a‐hydroxy flavin: the putative bacterial luciferase fluorophore. We find an increase in fluorescence quantum yield upon reaching the glass transition temperature of the solvent. We then employ multiconfigurational quantum chemical methods to map the excited‐state deactivation path of the system. The result reveals a shallow but barrierless excited state deactivation path that leads to a conical intersection displaying an orthogonal out‐of‐plane distortion of the terminal pyrimidine ring. The intersection structure readily explains the observed spectroscopic behavior in terms of an excited‐state barrier imposed by the rigid glass cavity. 相似文献
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L. F. Errea A. Macías L. Mndez I. Rabadn A. Riera P. Sanz 《International journal of quantum chemistry》2002,86(2):182-189
We present cross sections for electron capture in N5++H2 collisions in the energy range 100 eV/amu≤E≤6 keV/amu. We employ a model potential aproximation to treat the interaction of the active electron with the cores, and a recently proposed method, which applies the independent particle model to evaluate the Hamiltonian matrix elements. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 相似文献
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《Mendeleev Communications》2020,30(3):355-358
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The influence of alcohol modifiers with different chain length on the migration time window in micellar electrokinetic chromatography (MEKC) has been studied. Highly polar alcohols like methanol and 1-propanol are typical aqueous phase modifiers. Higher alcohols like 1-butanol, 1-pentanol and 1-hexanol influence the micellar structure and are considered as micellar phase modifiers. The effect of long chain alcohols is small because of their low applicable concentrations. 相似文献
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Yan Wang Congyan Liu Yang Wang Chaofeng Zhu Xihai Chen Prof. Bo Liu 《ChemSusChem》2021,14(24):5434-5441
A large fraction of energy, including solar energy, is dissipated into ambient atmosphere as low-grade waste heat. Efficient utilization of such energy is critical to address the current energy crisis and global warming issue. Herein, the efficient near-IR (NIR)-photothermal, thermoelectric, and thus photo-thermo-electric conversion of polyoxovanadate compound {[Ni(1,10-phenanthroline)3][V14O34Cl]Cl, NiV14} in ionic liquid was achieved. The solution displayed a NIR-photothermal efficiency of 16.04 and 23.43 % at 808 and 1064 nm, respectively. Taking advantage of the synergetic thermodiffusive and thermogalvanic effects of various ion species in NiV14 solution, an open circuit voltage of approximately 0.45 V was obtained at ΔT=70 K generated by physical heating or NIR irradiation, indicating a large Seebeck coefficient of 6.38 mV K−1 and an optimized thermal power at 1.2 W m−2. The polyoxovanadate-ionic liquid system offers a new platform for efficiently utilizing not only low-grade thermal energy but also solar energy for electricity generation. 相似文献
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Interfacial slip between polymer melt under steady shear has been studied using a simplified multilayer structure. In this investigation, interfacial slip under dynamic shear was studied by calculating the angular displacements of the multilayer structure and its component layers. On the basis of the angular displacements, a slip index was defined to quantify the degree of interfacial slip. A relationship governing the rheological behavior of the multilayer structure under slip and nonslip condition was established. These results were correlated with equations derived from consideration of energy equilibrium in the multilayer structure. Polymer multilayer structures of high‐density polyethylene/polystyrene and liquid crystal polymer(LCP)/poly ethylene naphthalate(PEN) were investigated. Of all the polymers investigated, large interfacial slip was found at LCP/PEN interface under dynamic shear. The high rigidity and alignment along the interface of LCP molecules was believed to prevent chain entanglement in the interfacial layer and therefore promote interfacial slip at the interface. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2683–2693, 2005 相似文献
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Robin Schulte Dr. Sandra Afflerbach Prof. Dr. Heiko Ihmels 《European journal of organic chemistry》2023,26(5):e202201398
In the search for improved photochromic systems that may be used for the efficient reversible conversion of light into chemical energy, eight monoaryl-substituted norbornadienes are presented, which carry naphthyl, anthracenyl, or donor-acceptor-phenyl substituents to establish an extended π system. The substrates were synthesized by Suzuki-Miyaura coupling reactions, and their absorption properties, the key parameters of the photochromic equilibrium, and the energy storage density of the quadricyclane products were examined. It was observed that these compounds have favorable properties for chemical energy storage. Specifically, 2-(1-naphthyl)norbornadiene showed a pronounced red shift of the absorption, a long half-life (35 d) and a relatively high energy storage density (361 KJ/Kg) of the respective quadricyclane. Therefore, the so far neglected monoaryl-norbornadienes represent a useful and complementary class of compounds that should be considered in the development of efficient molecular solar thermal energy storage (MOST) compounds, which can reversibly convert sunlight into chemical energy. 相似文献
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研究酶的组装和催化反应不仅有利于探索生命活动的本质,同时对开发酶在工业合成、分析检测、疾病治疗等领域的实际应用价值具有重要的指导意义. 研究发现,酶的有效固定和有序组装是保持酶活性、酶促反应的稳定性和对酶催化过程进行控制的重要途径,而在纳米通道内进行单酶或多酶的有序组装,利用纳米通道的限域效应可有效保持酶的构型进而提高酶催化反应的选择性和催化效率,增强酶级联反应的动力学进程. 本文概述了近年来基于纳米通道的酶反应器在生物传感领域的研究进展,着重描述纳米通道限域空腔内酶的组装方法、酶催化反应及其动力学机制,并展望了基于纳米通道的酶反应器的应用前景. 相似文献
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López-Duarte I Dieu LQ Dolamic I Martínez-Díaz MV Torres T Calzaferri G Brühwiler D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(6):1855-1862
The synthesis of stopcocks based on zinc phthalocyanine for selective adsorption at the channel entrances of zeolite L is reported. The introduction of either an inert SiMe? moiety, an imidazolium cation or a reactive isothiocyanate (NCS) group allows attachment to the channel entrances of zeolite L through van der Waals interactions, electrostatic interactions, or covalent binding, respectively. Stopcocks that rely on van-der-Waals-driven adsorption require careful selection of the solvent used for the deposition onto the zeolite surface to avoid a nonspecific distribution of the molecules. Regarding the design of photonic antenna systems, a stopcock with a cationic tail was found to be the most convenient, based on the observation that efficient energy transfer from molecules located in the zeolite nanochannels is more readily obtained than in the other cases. 相似文献
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太阳能光解水制氢的研究进展 总被引：48，自引：0，他引：48
本文概述了利用光催化技术催化分解水制氢的反应机理和研究进展。结合作者的最近研究,重点描述了TiO2及过渡金属氧化物,层状金属氧化物以及某些能利用可见光的光催化材料的结构和光催化特性,阐述了核课题的意义和今后的研究方向。 相似文献
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化石能源枯竭以及地球环境污染已经成为并且在未来相当长一段时期内都将是人类面临的最严峻的危机之一.因此,寻找清洁的替代能源形式、有效的能量存储方式以及高效的能源利用途径是目前科学研究的热点.自从其高质量样品被制备和研究以来,石墨烯一直吸引着全世界科研工作者的兴趣;它的一系列独特的物理化学性质,为其在能源领域的应用提供了无限前景.本文对石墨烯在能源领域的最新研究进展以及其工业化应用作了简要综述,具体内容包括石墨烯材料在以下领域的应用：能源储存器件类,如超级电容器和锂离子电池;能源转化装置类,如燃料电池和太阳能电池. 相似文献
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C2F4 was excited by using a 150 fs pulse in its longest-wavelength band to the Rydberg (3 s) state and then probed by photoionization techniques at 810 nm. The molecule relaxes in two consecutive steps (time constants 29 and 118 fs), probably via the pipi* state, which is lowered in energy by stretching and twisting the C=C bond. A coherent oscillation (350 fs) was found, which we assign to an overtone of the twist vibration (47.6 cm(-1)) in this state. we also conclude that dissociation to singlet and some triplet CF2 only takes place in the hot ground state of C2F4, from where also the C2F4 triplet state is populated. The potentials and their conical intersections are discussed with respect to relaxation and dissociation, including also some new considerations of thermal processes. 相似文献
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John B. Goodenough 《Journal of Chemical Sciences》1979,88(2):69-89
The transition from reliance on fossil fuels to long-term energy sources is a most urgent technical challenge to modern civilization.
This paper outlines some materials problems associated with the transition to solar energy as a distributed source of (a)
low-temperature heat for hot water, domestic heating, and refrigeration/air-conditioning, (b) electric power, and (c) fuel.
Academy lecture delivered at the Indian Institute of Science, Bangalore, on 6 December 1978. 相似文献