Quantum algorithms for optimal effective theory of many-body systems

A common situation in quantum many-body physics is that the underlying theories are known but too complicated to solve efficiently. In such cases, one usually builds simpler effective theories as low-energy or large-scale alternatives to the original theories. Here the central tasks are finding the optimal effective theories among a large number of candidates and proving their equivalence to the original theories. Recently quantum computing has shown the potential of solving quantum many-body systems by exploiting its inherent parallelism. It is thus an interesting topic to discuss the emergence of effective theories and design efficient tools for finding them based on the results from quantum computing. As the first step towards this direction, in this paper, we propose two approaches that apply quantum computing to find the optimal effective theory of a quantum many-body system given its full Hamiltonian. The first algorithm searches the space of effective Hamiltonians by quantum phase estimation and amplitude amplification. The second algorithm is based on a variational approach that is promising for near-future applications.Comment: 8 pages, 4 figure

Signals of Hotel Effort on Enhancing IAQ and Booking Intention: Effect of Customer's Body Mass Index Associated with Sustainable Marketing in Tourism

Since outdoor air pollutants may penetrate into hotels, indoor air quality (IAQ) has recently developed as an important criterion for tourists' decision to choose traveling destinations and for business travelers to select accommodation. Thus, some hoteliers have raised concern about the negative effects of emerging air quality issues on guests' experience and are willing to invest in improving the IAQ. Unlike hotel's currently offered services and products which are observable, the improved IAQ is almost invisible and the mitigation technology of air pollutants is new to hoteliers, consumers and researchers in the tourism. Hence, the search and understanding of the relationship of signals communicating hotel's effort on air quality enhancement and booking intention plus the mediating and moderating factors becomes the main objective of the research and can fill the knowledge gap plus meet the practical need. The study found that the more reinforced IAQ effort included in the website presentation, the higher the travelers' booking intention. The travelers' trust belief on hotel partially mediated the relationship between travelers' perception of reinforced IAQ effort input by hoteliers and their booking intention. Further, the study finds that enhancement of online booking intention do exist in segment of travelers who are high health-conscious. Also, the influence of health-conscious traveler's perception of hotel IAQ enhancement effort via portal on dependent variable-hotel booking was statistically significant. The findings enable hotel managers to have a deeper understanding of the relationship between the potential customers' booking intention on hotel rooms and the online marketing communication signals mediated by their trust on hotel's cleaning air effort. The results can serve as a reference for designing more effective 2 marketing communication programs and channels for hotels' endeavor to improve indoor air quality, especially sustaining the tourism development in the post epidemic era. Also, the study unveils some applied measures in improving hotel air quality not being documented in hospitality and tourism journals

Current evidence, clinical applications, and future directions of transcranial magnetic stimulation as a treatment for ischemic stroke

Transcranial magnetic stimulation (TMS) is a non-invasive brain neurostimulation technique that can be used as one of the adjunctive treatment techniques for neurological recovery after stroke. Animal studies have shown that TMS treatment of rats with middle cerebral artery occlusion (MCAO) model reduced cerebral infarct volume and improved neurological dysfunction in model rats. In addition, clinical case reports have also shown that TMS treatment has positive neuroprotective effects in stroke patients, improving a variety of post-stroke neurological deficits such as motor function, swallowing, cognitive function, speech function, central post-stroke pain, spasticity, and other post-stroke sequelae. However, even though numerous studies have shown a neuroprotective effect of TMS in stroke patients, its possible neuroprotective mechanism is not clear. Therefore, in this review, we describe the potential mechanisms of TMS to improve neurological function in terms of neurogenesis, angiogenesis, anti-inflammation, antioxidant, and anti-apoptosis, and provide insight into the current clinical application of TMS in multiple neurological dysfunctions in stroke. Finally, some of the current challenges faced by TMS are summarized and some suggestions for its future research directions are made

Low temperature preparation of dense and highly conductive NASICON electrolyte by solid-state reactive sintering

Funding Information: This work was funded by the Natural Science Foundation of Tianjin ( 18JCQNJC02800 ). Publisher Copyright: © 2021 Elsevier B.V.NASICON-type solid-state electrolyte is characterized by high electrical conductivity but its application in all-solid-state battery is limited by the high sintering temperature and poor interface contact with the electrodes. Here, solid-state reactive sintering, without intermediate calcination and ball-milling steps and no sintering additive, is proposed to prepare dense and highly conductive NASICON at lower temperatures. The samples sintered at 950 and 1000 °C achieve relative density of ~90% and high ion conductivity of 8.43 × 10−4 and 1.48 × 10−3 S cm−1 at room temperature, respectively. The reasonable interface contact between sodium metal and 950 °C-sintered electrolyte affords the symmetric sodium battery to cycle stably at 0.05 mA cm−2 for ~1000 h and full battery at 0.1C (0.02 mA cm−2) at room temperature. This work provides a new strategy to prepare NASICON solid-state electrolyte, which can be extended to prepare other solid-state electrolytes and thus promote the development of all-solid-state battery.Peer reviewe

Coupling Tetraalkylammonium and Ethylene Glycol Ether Side Chain To Enable Highly Soluble Anthraquinone-Based Ionic Species for Nonaqueous Redox Flow Battery

Funding Information: The work was financially supported by the National Natural Science Foundation of China (21636007). Publisher Copyright: © 2022 American Chemical Society.Nonaqueous redox flow batteries (NARFBs) have promise for large-scale energy storage with high energy density. Developing advanced active materials is of paramount importance to achieve high stability and energy density. Herein, we adopt the molecular engineering strategy by coupling tetraalkylammonium and an ethylene glycol ether side chain to design anthraquinone-based ionic active species. By adjusting the length of the ethylene glycol ether chain, an ionic active species 2-((9,10-dioxo-9,10-dihydroanthracen-1-yl)amino)-N-(2-(2-methoxyethoxy)ethyl)-(N,N-dimethylethan-1-aminium)-bis(trifluoromethylsulfonyl)imide (AQEG2TFSI) with high solubility and stability is obtained. Paired with a FcNTFSI cathode, the full battery provides an impressive cycling performance with discharge capacity retentions of 99.96% and 99.74% per cycle over 100 cycles with 0.1 and 0.4 M AQEG2TFSI, respectively.Peer reviewe

Molecular engineering the naphthalimide compounds as High-Capacity anolyte for nonaqueous redox flow batteries

Funding Information: The work was financially supported by the National Natural Science Foundation of China (21636007). Publisher Copyright: © 2022 Elsevier B.V.Nonaqueous redox flow batteries (NARFBs) hold great promise to offer high energy density due to the broader electrochemical window. However, the achieved energy density is relatively low due to the poor stability and low solubility of redox active materials. Herein, we demonstrate that N-substituted naphthalimides can be employed as stable anolyte material for NARFBs. N-(naphthalimidoethyl)-N,N-dimethyl-N-ethylammonium bis(trifluoromethane-sulfonyl)imide (NI-TFSI) was designed via an ionic modification strategy, resulting in enhanced solubility from 0.31 M to 1.22 M. The NARFB based on NI-TFSI exhibits stable cycling with 90.3% discharge capacity retention over 100 cycles and high-rate capability with the average discharge capacity of 1.27 Ah L-1 even at 120 mA cm−2. Benefiting from the high solubility of the redox active materials, capacity of 16.3 Ah L-1 and energy density of 35.6 Wh L−1 can be achieved at 1.0 M, which represent the benchmark of high-energy–density NARFBs.Peer reviewe

Molecular engineering redox-active organic materials for nonaqueous redox flow battery

Publisher Copyright: © 2022 Elsevier LtdNonaqueous redox flow batteries (NARFBs) have the potential as high-energy-density electrochemical storage systems due to their wider electrochemical windows compared with their aqueous counterpart. Before possible commercial application, three major performance metrics (energy density, power density, and cycling stability) of NARFBs need to be improved. With molecular diversity and scalability, redox-active organic materials (ROMs) are considered as promising redox-active materials for establishing sustainable NARFBs. Reasonable molecular engineering ROMs can obtain desired physicochemical properties, leading to the improvement of battery performance metrics. This mini review comprehensively summarizes the NARFB improvement through molecular engineering ROMs over the recent years, aiming to provide a guideline for the future battery design.Peer reviewe

Recent Progress in the Integration of CO2 Capture and Utilization

Publisher Copyright: © 2023 by the authors.CO2 emission is deemed to be mainly responsible for global warming. To reduce CO2 emissions into the atmosphere and to use it as a carbon source, CO2 capture and its conversion into valuable chemicals is greatly desirable. To reduce the transportation cost, the integration of the capture and utilization processes is a feasible option. Here, the recent progress in the integration of CO2 capture and conversion is reviewed. The absorption, adsorption, and electrochemical separation capture processes integrated with several utilization processes, such as CO2 hydrogenation, reverse water–gas shift reaction, or dry methane reforming, is discussed in detail. The integration of capture and conversion over dual functional materials is also discussed. This review is aimed to encourage more efforts devoted to the integration of CO2 capture and utilization, and thus contribute to carbon neutrality around the world.Peer reviewe

Amorphous Co[sbnd]Mn binary oxides loaded on porous carbon nanosheet as bifunctional electrocatalysts for rechargeable zinc-air battery

Funding Information: This work was funded by the National Natural Science Foundation of China (Grant No. 51702230 ). Publisher Copyright: © 2023 Elsevier LtdRechargeable zinc-air battery (RZAB) is very promising for large-scale energy storage whereas is impeded by the sluggish oxygen reduction/evolution reactions (ORR/OER). Developing high-performance yet cost-effective ORR/OER bifunctional catalysts is critical to accelerating its market penetration. Here, amorphous Co[sbnd]Mn binary oxides loaded on porous carbon nanosheets are prepared by a facile photochemical metal- organic deposition method. The evolution of composition, microstructure, ORR/OER performance with the calcination temperature is systematically investigated. The amorphous CoMn2Ox supported on carbon nanosheets shows higher ORR/OER bifunctional electrochemical performance in terms of activity and stability. The resultant RZAB with the amorphous CoMn2Ox on carbon nanosheets as air electrode delivers a peak power density of 89.6 mW cm−2 and maintains stable operation for ∼500 cycles at 10 mA cm−2. The ORR/OER bifunctional performance is closely associated with the microstructure, oxidation states of Co/Mn species and their corresponding proportions. Although there is great room to performance enhancement, this work sheds light on the development of high-performance and cheap ORR/OER bifunctional catalysts for rechargeable metal-air batteries by engineering the crystallinity of the metal oxides.Peer reviewe

Redox flow battery as an emerging technology: current status and research trends

C. Flox acknowledges financial support by Ministery of Science Spain, AEI Severo Ochoa Grant CEX2019-000917-S and European Commission under the grant MSCA-IF-EF-ST, proposal number 101026162. C. Zhang and Y.Li acknowledge the financial supports from the National Natural Science Foundation of China (21636007, 2016) and the Academy of Finland under contract No. 348403 (2022).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).Peer reviewe