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Comparison of differential evolution, particle swarm optimization,quantum-behaved particle swarm optimization, and quantum evolutionary algorithm for preparation of quantum states 被引量:1
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作者 程鑫 鲁秀娟 +1 位作者 刘亚楠 匡森 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期53-59,共7页
Four intelligent optimization algorithms are compared by searching for control pulses to achieve the preparation of target quantum states for closed and open quantum systems, which include differential evolution(DE), ... Four intelligent optimization algorithms are compared by searching for control pulses to achieve the preparation of target quantum states for closed and open quantum systems, which include differential evolution(DE), particle swarm optimization(PSO), quantum-behaved particle swarm optimization(QPSO), and quantum evolutionary algorithm(QEA).We compare their control performance and point out their differences. By sampling and learning for uncertain quantum systems, the robustness of control pulses found by these four algorithms is also demonstrated and compared. The resulting research shows that the QPSO nearly outperforms the other three algorithms for all the performance criteria considered.This conclusion provides an important reference for solving complex quantum control problems by optimization algorithms and makes the QPSO be a powerful optimization tool. 展开更多
关键词 quantum control state preparation intelligent optimization algorithm
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Synergistic stabilization of CsPbI_(3) inorganic perovskite via 1D capping and secondary growth 被引量:1
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作者 Jingya Mi Yuetian Chen +4 位作者 Xiaomin Liu Xingtao Wang Yanfeng Miao Yabing Qi Yixin Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期387-392,共6页
Cesium lead iodide(CsPbI_(3)) perovskite has gained great attention in the photovoltaic(PV) community because of its unique optoelectronic properties, good chemical stability and appropriate bandgap for sunlight harve... Cesium lead iodide(CsPbI_(3)) perovskite has gained great attention in the photovoltaic(PV) community because of its unique optoelectronic properties, good chemical stability and appropriate bandgap for sunlight harvesting applications. However, compared to solar cells fabricated from organic-inorganic hybrid perovskites, the commercialization of devices based on all-inorganic CsPbI_(3) perovskites still faces many challenges regarding PV performance and long-term stability. In this work, we discovered that tetrabutylammonium bromide(TBABr) post-treatment to CsPbI_(3) perovskite films could achieve synergistic stabilization with both TBA+cation intercalation and Br-doping. Such TBA^(+) cation intercalation leads to onedimensional capping with TBAPb I3 perovskite formed in situ, while the Br-induced crystal secondary growth helps effectively passivate the defects of CsPbI_(3) perovskite, thus enhancing the stability. In addition, the incorporation of TBABr can improve energy-level alignment and reduce interfacial charge recombination loss for better device performance. Finally, the highly stable TBABr-treated CsPbI_(3)-based perovskite solar cells show reproducible photovoltaic performance with a champion efficiency up to 19.04%, while retaining 90% of the initial efficiency after 500 h storage without encapsulation. 展开更多
关键词 CsPbI_(3)inorganic perovskite All-inorganic perovskite solar cell One-dimensional capping Synergistic stabilization
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Cesarean Scar Pregnancy: A Report of 11 Cases and Review of the Literature Regarding Subsequent Pregnancy 被引量:4
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作者 Chiaki Heshiki Keiko Mekaru +6 位作者 Maho Miyagi Sugiko Oishi Kozue Akamine Hitoshi Sugiyama Tadatsugu Kinjo Hitoshi Masamoto Yoichi Aoki 《Open Journal of Obstetrics and Gynecology》 2016年第1期8-15,共8页
Background: There is no consensus regarding the optimal treatment for cesarean scar pregnancy (CSP) because treatment efficacy, safety, and the influence on subsequent pregnancy must be taken into consideration. Here ... Background: There is no consensus regarding the optimal treatment for cesarean scar pregnancy (CSP) because treatment efficacy, safety, and the influence on subsequent pregnancy must be taken into consideration. Here we report our experience with 11 cases of CSP and review the literature regarding subsequent pregnancy. Methods: Records of 11 CSP cases that were treated at our hospital were retrospectively reviewed. CSP was treated by local methotrexate (MTX) injection or laparotomic or laparoscopic removal of the gestational mass and myometrial repair. Outcome of subsequent pregnancy after treatment was followed-up until delivery. Results: Local MTX injection was performed for six cases, laparotomic removal of the gestational mass and myometrial repair was performed for two, and laparoscopic removal of the gestational mass and myometrial repair was performed for three. The uterus was preserved in all cases. After CSP treatment, eight pregnancies occurred in five cases, resulting in six live births and two miscarriages. Conclusion: Advantages and disadvantages of various treatment methods for CSP continue to be elucidated. Serum hCG level, location of the gestational mass, thickness of the lower uterine segment at the time of diagnosis, and whether the patient wishes for fertility preservation should be considered when choosing a treatment plan. 展开更多
关键词 Cesarean Scar Pregnancy METHOTREXATE Fertility Preservation
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Development of OIST Wave Energy Converter Monitoring System for Maldives Island Experiment
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作者 Hideki Takebe Katsutoshi Shirasawa +2 位作者 Jun Fujita Shuji Misumi Tsumoru Shintake 《Journal of Energy and Power Engineering》 2018年第8期375-384,共10页
This paper describes experiments with our self-built Wave Energy Convertor(WEC)monitoring system in the Maldives and demonstrates how we developed a horizontal-axis type,half-scale,wave energy converter(WEC)that gener... This paper describes experiments with our self-built Wave Energy Convertor(WEC)monitoring system in the Maldives and demonstrates how we developed a horizontal-axis type,half-scale,wave energy converter(WEC)that generates electricity in the coastal breaking wave zone.In order to measure this power generator and turbine’s efficiency,voltage and current were measured by pulling the generator with a 35 cm diameter turbine(half scale).We obtained data showing 400 W peak power in water speed of 3.1 m/s.Consequently,we assembled two sets of WEC,placed them near the shoreline on Kandooma Island in the Maldives in May 2018,and measured the wave energy at the breaking wave zone.A monitoring system was set up in one rack for the two sets of WECs,connected simultaneously.Two outputs of the generators were rectified and connected to power resistors and internal LED displays.The outputs could also be switched to connect to 24 electric double layer capacitors(EDLC),in order to perform a continuous lighting test of external high-power LED lights.The wave power data were continuously saved by an automated data logger and could be transferred from the installation site,to Japan via the Internet.The wave power was measured on Kandooma Island in the Maldives for a long period,and is still ongoing.Examples of the obtained data are shown in this paper. 展开更多
关键词 Generator WEC WAVE ENERGY converter BREAKING WAVE turbine sustainable ENERGY EDLC super-capacitor MALDIVES OIST Internet remote monitoring
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整合素诱导多肽组装构建细胞外支架机械调控线粒体动态网络
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作者 张奇正 Sona R.Roy +1 位作者 胡训武 张晔 《医用生物力学》 CAS CSCD 北大核心 2024年第S01期654-654,共1页
目的癌细胞通常表现出升高的糖酵解活性,即沃尔堡效应。这种现象是由于线粒体功能障碍导致的缺氧所引起,进而导致癌细胞对治疗的抵抗性增强。细胞外基质可通过细胞机械信号转导影响线粒体形态和功能。因此,合成细胞外支架可通过改变细... 目的癌细胞通常表现出升高的糖酵解活性,即沃尔堡效应。这种现象是由于线粒体功能障碍导致的缺氧所引起,进而导致癌细胞对治疗的抵抗性增强。细胞外基质可通过细胞机械信号转导影响线粒体形态和功能。因此,合成细胞外支架可通过改变细胞机械信号参与到线粒体的调控中,而作为一种治疗干预手段。然而,目前对于合成细胞外支架在这方面的影响和作用仍未被充分探究。方法采用整合素诱导多肽原位组装的方法,引入合成细胞外支架,与癌细胞之间建立密切的相互作用,并动态地调控线粒体网络的裂分-融合动力学。结果和结论实验证实,基于合成细胞外支架的干预手段通过改变细胞骨架结构,不仅能够抑制癌细胞的迁移能力,还能够阻碍癌细胞内线粒体的裂分和糖酵解活性。通过这种创新的治疗策略,有望克服癌细胞的抗药性问题,提高治疗的效果。这一发现为癌症研究和治疗提供了新的方向,有望推动抗癌治疗的进一步发展和改善。 展开更多
关键词 线粒体功能障碍 外支架 细胞内线粒体 抗癌治疗 癌症研究 抗药性问题 细胞外基质 糖酵解
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Additives in metal halide perovskite films and their applications in solar cells 被引量:4
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作者 Zonghao Liu Luis K.Ono Yabing Qi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期215-228,I0007,共15页
The booming growth of organic-inorganic hybrid lead halide perovskite solar cells have made this promising photovoltaic technology to leap towards commercialization.One of the most important issues for the evolution f... The booming growth of organic-inorganic hybrid lead halide perovskite solar cells have made this promising photovoltaic technology to leap towards commercialization.One of the most important issues for the evolution from research to practical application of this technology is to achieve high-throughput manufacturing of large-scale perovskite solar modules.In particular,realization of scalable fabrication of large-area perovskite films is one of the essential steps.During the past ten years,a great number of approaches have been developed to deposit high quality perovskite films,to which additives are introduced during the fabrication process of perovskite layers in terms of the perovskite grain growth control,defect reduction,stability enhancement,etc.Herein,we first review the recent progress on additives during the fabrication of large area perovskite films for large scale perovskite solar cells and modules.We then focus on a comprehensive and in-depth understanding of the roles of additives for perovskite grain growth control,defects reduction,and stability enhancement.Further advancement of the scalable fabrication of high-quality perovskite films and solar cells using additives to further develop large area,stable perovskite solar cells are discussed. 展开更多
关键词 Perovskite solar cell ADDITIVE Solar modules Film quality
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Effect of acceleration threshold on the phase transition in a cellular automaton traffic flow model 被引量:4
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作者 金诚杰 王炜 +1 位作者 高坤 姜锐 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期283-288,共6页
In this paper, we incorporate new parameters into a cellular automaton traffic flow model proposed in our previous paper [Jin et al. 2010 J. Stat. Mech. 2010 P03018]. Through these parameters, we adjust the anticipate... In this paper, we incorporate new parameters into a cellular automaton traffic flow model proposed in our previous paper [Jin et al. 2010 J. Stat. Mech. 2010 P03018]. Through these parameters, we adjust the anticipated velocity and the acceleration threshold separately. It turns out that the flow rate of synchronized flow mainly changes with the anticipated velocity, and the F →S phase transition feature mainly changes with the acceleration threshold. Therefore, we conclude that the acceleration threshold is the major factor affecting the F → S phase transition. 展开更多
关键词 traffic flow cellular automaton synchronized flow phase transition
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Up-Scalable Fabrication of SnO_(2)with Multifunctional Interface for High Performance Perovskite Solar Modules 被引量:3
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作者 Guoqing Tong Luis KOno +3 位作者 Yuqiang Liu Hui Zhang Tongle Bu Yabing Qi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第10期200-213,共14页
Tin dioxide(SnO_(2))has been demonstrated as one of the promising electron transport layers for high-efficiency perovskite solar cells(PSCs).However,scalable fabrication of SnO_(2) films with uniform coverage,desirabl... Tin dioxide(SnO_(2))has been demonstrated as one of the promising electron transport layers for high-efficiency perovskite solar cells(PSCs).However,scalable fabrication of SnO_(2) films with uniform coverage,desirable thickness and a low defect density in perovskite solar mod-ules(PSMs)is still challenging.Here,we report preparation of high-quality large-area SnO_(2) films by chemical bath depo-sition(CBD)with the addition of KMnO_(4).The strong oxidiz-ing nature of KMnO_(4) promotes the conversion from Sn(II)to Sn(VI),leading to reduced trap defects and a higher carrier mobility of SnO_(2).In addition,K ions diffuse into the per-ovskite film resulting in larger grain sizes,passivated grain boundaries,and reduced hysteresis of PSCs.Furthermore,Mn ion doping improves both the crystallinity and the phase stability of the perovskite film.Such a multifunctional interface engineering strategy enabled us to achieve a power conversion efficiency(PCE)of 21.70% with less hysteresis for lab-scale PSCs.Using this method,we also fabricated 5×5 and 10×10 cm^(2) PSMs,which showed PCEs of 15.62% and 11.80%(active area PCEs are 17.26%and 13.72%),respectively.For the encapsulated 5×5 cm^(2) PSM,we obtained a T80 operation lifetime(the lifespan during which the solar module PCE drops to 80%of its initial value)exceeding 1000 h in ambient condition. 展开更多
关键词 Perovskites Solar modules Operational stability Interface passivation SnO_(2)
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Scalable solution coating of the absorber for perovskite solar cells 被引量:1
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作者 Mikas Remeika Yabing Qi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第4期1101-1110,共10页
Perovskite-based solar cell technology has advanced significantly and the power conversion efficiencies are nowadays on par with commercialized photovoltaic technologies. To realize the potential of perovskite solar c... Perovskite-based solar cell technology has advanced significantly and the power conversion efficiencies are nowadays on par with commercialized photovoltaic technologies. To realize the potential of perovskite solar cells, the focus is now shifting to scalable fabrication technologies that will enable low-cost solution processing of perovskite solar cells over large areas and with high yields. This review article discusses the fundamental concerns that arise when transitioning from laboratory to large area solution coating, available scalable coating technologies, and their applicability to the fabrication of high-performance perovskite solar cells. We find that a significant amount of work has been done to test scalable coating technologies, but also that often the methods that led to highest-performing cells in the laboratory (e.g. antisolvent processing) show limited compatibility with scalable coating methods. To achieve a high-yield and low-cost process, development must emphasize a high degree of control provided by sequential conversion of perovskite films and engineering of additives that fine-tune coating properties of perovskite precursor inks. 展开更多
关键词 Perovskite solar cell COATING SOLUTION SCALABLE
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The Main Progress of Perovskite Solar Cells in 2020-2021 被引量:6
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作者 Tianhao Wu Zhenzhen Qin +19 位作者 Yanbo Wang Yongzhen Wu Wei Chen Shufang Zhang Molang Cai Songyuan Dai Jing Zhang Jian Liu Zhongmin Zhou Xiao Liu Hiroshi Segawa Hairen Tan Qunwei Tang Junfeng Fang Yaowen Li Liming Ding Zhijun Ning Yabing Qi Yiqiang Zhang Liyuan Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第10期113-130,共18页
Perovskite solar cells(PSCs)emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world.Both the efficiency and stability of PSC... Perovskite solar cells(PSCs)emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world.Both the efficiency and stability of PSCs have increased steadily in recent years,and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step.This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency,stability,perovskite-based tandem devices,and lead-free PSCs.Moreover,a brief discussion on the development of PSC modules and its challenges toward practical application is provided. 展开更多
关键词 Perovskite solar cells Stability Solar module Perovskite-based tandem devices Lead-free perovskite
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Strategies and methods for fabricating high quality metal halide perovskite thin films for solar cells
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作者 Helian Sun Pengfei Dai +3 位作者 Xiaotong Li Jinyan Ning Shenghao Wang Yabing Qi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期300-333,共34页
With the development of human society,the problems of environmental deterioration and energy shortage have become increasingly prominent.In order to solve these problems,metal halide perovskite solar cells(PSCs)stand ... With the development of human society,the problems of environmental deterioration and energy shortage have become increasingly prominent.In order to solve these problems,metal halide perovskite solar cells(PSCs)stand out because of their excellent properties(i.e.,high optical absorption coefficient,long carrier lifetime and carrier diffusion length,adjustable band gap)and have been widely studied.PSCs with low cost,high power conversion efficiency and high stability are the future development trend.The quality of perovskite film is essential for fabricating PSCs with high performance.To provide a full picture of realizing high performance PSCs,this review focuses on the strategies for preparing high quality perovskite films(including antisolvent,Lewis acid-base,additive engineering,scaleable fabrication,strain engineering and band gap adjustment),and therefore to fabricate high performance PSCs and to accelerate the commercialization. 展开更多
关键词 Metal halide perovskite Solar cell PHOTOVOLTAIC ANTISOLVENT Lewis acid-base ADDITIVE
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Quantum Statistical Theory of Superconductivity in MgB2
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作者 S. Fujita A. Suzuki Y. Takato 《Journal of Modern Physics》 2016年第12期1546-1557,共13页
A quantum statistical theory of the superconductivity in MgB<sub>2</sub> is developed regarding it as a member of the graphite intercalation compound. The superconducting temperature T<sub>c</sub&... A quantum statistical theory of the superconductivity in MgB<sub>2</sub> is developed regarding it as a member of the graphite intercalation compound. The superconducting temperature T<sub>c</sub> for MgB<sub>2</sub>, C<sub>8</sub>K ≡ KC<sub>8</sub>, CaC<sub>6</sub>, are 39 K, 0.6 K, 11.5 K, respectively. The differences arise from the lattice structures. In the plane perpendicular to the c-axis, B’s form a honeycomb lattice with the nearest neighbour distance while Mg’s form a base-hexagonal lattice with the nearest neighbour distance above and below the B-plane distanced by . The more compact B-plane becomes superconducting due to the electron-phonon attraction. Starting with the generalized Bardeen- Cooper-Schrieffer (BCS) Hamiltonian and solving the generalized Cooper equation, we obtain a linear dispersion relation for moving Cooper pairs. The superconducting temperature T<sub>c</sub> identified as the Bose-Einstein condensation temperature of the Cooper pairs in two dimensions is given by , where is the Cooper pair density, the Boltzmann constant. The lattices of KC<sub>8</sub> and CaC<sub>6</sub> are clearly specified. 展开更多
关键词 Crystal Structure BCS Hamiltonian Electron-Phonon Interaction Cooper Pairs Bose-Einstein Condensation SUPERCONDUCTIVITY
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Impacts on Bats by a Supertyphoon vs.Ordinary Typhoons along a Habitat Urbanization Gradient
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作者 Vladimir Dinets Nicholas R.Friedman +2 位作者 Masako Ogasawara Masashi Yoshimura Evan P.Economo 《Research in Ecology》 2023年第2期14-27,共14页
Two major human-caused threats to ecosystems are habitat modification and the increasing frequency and intensity of extreme weather events.To study the combined effect of these threats,the authors used acoustic monito... Two major human-caused threats to ecosystems are habitat modification and the increasing frequency and intensity of extreme weather events.To study the combined effect of these threats,the authors used acoustic monitoring of bats along a habitat modification gradient on the island of Okinawa,Japan.During the observation period,the island experienced numerous typhoons and one supertyphoon.Native bat species remained active even at high wind speeds(up to 30 m/s in some cases).Milder typhoons had no observable effect on bat populations,with activity levels fully recovering within a few hours or days.The super typhoon also did not seem to affect bats in fully or partially forested habitats but caused their local disappearance at the urban site,which they have not re-colonized three years after the event.Notably,bats that disappeared at the urban site were species roosting in well-protected places such as caves and concrete structures.In all cases,the biomass of small flying insects and the acoustic activity of insects recovered within days after extreme weather events.Thus,the striking difference between habitats in supertyphoon effects on bats cannot be explained by the super typhoon directly killing bats,destroying their roosting sites,or decreasing the abundance of their prey.The results underscore the importance of preserving natural habitats in areas particularly affected by changing climate and show that the survival of species and ecosystems during the numerous episodes of climate change in the Earth’s history does not necessarily mean their ability to survive the accelerating climate change of our time. 展开更多
关键词 Acoustic monitoring CHIROPTERA Climate change Extreme weather events Hurricanes OKEON OKINAWA Urbanization gradient
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Twisted fiber microfluidics:a cutting-edge approach to 3D spiral devices
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作者 Shunsuke Kato Daniel W.Carlson +1 位作者 Amy Q.Shen Yuanyuan Guo 《Microsystems & Nanoengineering》 SCIE EI CSCD 2024年第1期193-202,共10页
The development of 3D spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological disciplines.While tr... The development of 3D spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological disciplines.While traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates Dean drag forces,eliminating the necessity for external fields in fluid manipulation.Nevertheless,fabricating 3D spiral microfluidics remains a labor-intensive and costly endeavor,hindering its widespread adoption.Moreover,conventional lithographic methods primarily yield 2D planar devices,thereby limiting the selection of materials and geometrical configurations.To address these challenges,this work introduces a streamlined fabrication method for 3D spiral microfluidic devices,employing rotational force within a miniaturized thermal drawing process,termed as mini-rTDP.This innovation allows for rapid prototyping of twisted fiber-based microfluidics featuring versatility in material selection and heightened geometric intricacy.To validate the performance of these devices,we combined computational modeling with microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3D flow dynamics.Our results corroborate the presence of a steady secondary flow,underscoring the effectiveness of our approach.Our 3D spiral microfluidics platform paves the way for exploring intricate microflow dynamics,with promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems. 展开更多
关键词 thereby STRAIGHT TWISTED
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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as highly efficient and stable acidic oxygen evolution catalysts
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作者 Jonathan Ruiz Esquius Alec P LaGrow +5 位作者 Haiyan Jin Zhipeng Yu Ana Araujo Rita Marques Adélio Mendes Lifeng Liu 《Materials Futures》 2024年第1期165-180,共16页
Proton exchange membrane(PEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal cata... Proton exchange membrane(PEM)water electrolysis represents a promising technology for green hydrogen production,but its widespread deployment is greatly hindered by the indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for the energy-demanding oxygen evolution reaction(OER).Herein,we report a new sequential precipitation approach to the synthesis of mixed Ir-nickel(Ni)oxy-hydroxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce the utilisation of scarce and precious Ir while maintaining its good acidic OER performance.When tested in strongly acidic electrolyte(0.1 M HClO_(4)),the optimised IrNi1Ox/ATO shows a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better than the IrOx/ATO control,particularly with a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exhibits substantially better catalytic stability than other reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h without obvious degradation.Our in-situ synchrotron-based x-ray absorption spectroscopy confirmed that the Ir^(3+)/Ir^(4+)species are the active sites for the acidic OER.Furthermore,the performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,which shows better activity and stability than other reference catalysts.The IrNi1Ox/ATO reported in this work is a promising alternative to commercial IrO_(2) based catalysts for PEM electrolysis. 展开更多
关键词 mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly
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On-Surface Synthesis of Anthracene-Fused Zigzag Graphene Nanoribbons from 2,7-Dibromo-9,9′-bianthryl Reveals Unexpected Ring Rearrangements
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作者 Xiushang Xu Amogh Kinikar +5 位作者 Marco Di Giovannantonio Carlo A.Pignedoli Pascal Ruffieux Klaus Müllen Roman Fasel Akimitsu Narita 《Precision Chemistry》 2024年第2期81-87,共7页
On-surface synthesis has emerged as a powerful strategy to fabricate unprecedented forms of atomically precise graphene nanoribbons(GNRs).However,the on-surface synthesis of zigzag GNRs(ZGNR)has met with only limited ... On-surface synthesis has emerged as a powerful strategy to fabricate unprecedented forms of atomically precise graphene nanoribbons(GNRs).However,the on-surface synthesis of zigzag GNRs(ZGNR)has met with only limited success.Herein,we report the synthesis and on-surface reactions of 2,7-dibromo-9,9′-bianthryl as the precursor towardπ-extended ZGNRs.Characterization by scanning tunneling microscopy and high-resolution noncontact atomic force microscopy clearly demonstrated the formation of anthracene-fused ZGNRs.Unique skeletal rearrangements were also observed,which could be explained by intramolecular Diels-Alder cycloaddition.Theoretical calculations of the electronic properties of the anthracene-fused ZGNRs revealed spin-polarized edge-states and a narrow bandgap of 0.20 eV. 展开更多
关键词 On-surface synthesis Graphene nanoribbon On-surface reaction REARRANGEMENT Edge state
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Climate and land-use interactively shape butterfly diversity in tropical rainforest and savanna ecosystems of southwestern China 被引量:6
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作者 Bai-Ge Miao Yan-Qiong Peng +3 位作者 Da-Rong Yang Yasuhiro Kubota Evan P.Economo Cong Liu 《Insect Science》 SCIE CAS CSCD 2021年第4期1109-1120,共12页
Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay be... Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity loss.Nevertheless,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood.Here,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China.Specifically,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients.We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems.These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization.The land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna.These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem.We also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna.Taken together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna.These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change. 展开更多
关键词 butterfly diversity climate change CONSERVATION habitat conversion SAVANNA tropical rainforest
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Evolution of Invertebrate Deuterostomes and Hox/ParaHox Genes 被引量:2
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作者 Tetsuro Ikuta 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2011年第3期77-96,共20页
Transcription factors encoded by Antennapedia-class homeobox genes play crucial roles in controlling development of animals, and are often found clustered in animal genomes. The Hox and ParaHox gene clusters have been... Transcription factors encoded by Antennapedia-class homeobox genes play crucial roles in controlling development of animals, and are often found clustered in animal genomes. The Hox and ParaHox gene clusters have been regarded as evolutionary sisters and evolved from a putative common ancestral gene complex, the ProtoHox cluster, prior to the divergence of the Cnidaria and Bilateria (bilaterally symmetrical animals). The Deuterostomia is a monophyletic group of animals that belongs to the Bilateria, and a sister group to the Protostomia. The deuterostomes include the vertebrates (to which we belong), invertebrate chordates, hemichordates, echinoderms and possibly xenoturbellids, as well as acoelomorphs. The studies of Hox and ParaHox genes provide insights into the origin and subsequent evolution of the bilaterian animals. Recently, it becomes apparent that among the Hox and ParaHox genes, there are significant variations in organization on the chromosome, expression pattern, and function. In this review, focusing on invertebrate deuterostomes, I first summarize recent findings about Hox and ParaHox genes. Next, citing unsolved issues, I try to provide clues that might allow us to reconstruct the common ancestor of deuterostomes, as well as understand the roles of Hox and ParaHox genes in the development and evolution of deuterostomes. 展开更多
关键词 invertebrate deuterostome HOX PARAHOX EVOLUTION
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The role of the CNOT1 subunit of the CCR4-NOT complex in mRNA deadenylation and cell viability 被引量:1
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作者 Kentaro Ito Akinori Takahashi +2 位作者 Masahiro Morita Toru Suzuki Tadashi Yamamoto 《Protein & Cell》 SCIE CSCD 2011年第9期755-763,共9页
The human CCR4-NOT deadenylase complex consists of at least nine enzymatic and non-enzymatic subunits.Accumulating evidence suggests that the non-enzymatic subunits are involved in the regulation of mRNA deadenylation... The human CCR4-NOT deadenylase complex consists of at least nine enzymatic and non-enzymatic subunits.Accumulating evidence suggests that the non-enzymatic subunits are involved in the regulation of mRNA deadenylation,although their precise roles remain to be established.In this study,we addressed the function of the CNOT1 subunit by depleting its expression in HeLa cells.Flow cytometric analysis revealed that the sub G1 fraction was increased in CNOT1-depleted cells.Virtually,the same level of the sub G1 fraction was seen when cells were treated with a mixture of siRNAs targeted against all enzymatic subunits,suggesting that CNOT1 depletion induces apoptosis by destroying the CCR4-NOT-associated deadenylase activity.Further analysis revealed that CNOT1 depletion leads to a reduction in the amount of other CCR4-NOT subunits.Importantly,the specific activity of the CNOT6L immunoprecipitates-associated deadenylase from CNOT1-depleted cells was less than that from control cells.The formation of P-bodies,where mRNA decay is reported to take place,was largely suppressed in CNOT1-depleted cells.Therefore,CNOT1 has an important role in exhibiting enzymatic activity of the CCR4-NOT complex,and thus is critical in control of mRNA deadenylation and mRNA decay.We further showed that CNOT1 depletion enhanced CHOP mRNA levels and activated caspase-4,which is associated with endoplasmic reticulum ER stress-induced apoptosis.Taken together,CNOT1 depletion structurally and functionally deteriorates the CCR4-NOTcomplex and induces stabilization of mRNAs,which results in the increment of translation causing ER stress-mediated apoptosis.We conclude that CNOT1 contributes to cell viability by securing the activity of the CCR4-NOT deadenylase. 展开更多
关键词 DEADENYLATION CCR4-NOT small interfering RNA P-BODIES APOPTOSIS
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Bandpass transmission spectra of a whisperinggallery microcavity coupled to an ultrathin fiber 被引量:1
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作者 FUCHUAN LEI RAFINO M.J.MURPHY +2 位作者 JONATHAN M.WARD YONG YANG SíLE NIC CHORMAIC 《Photonics Research》 SCIE EI 2017年第4期362-366,共5页
Tapered fibers with diameters ranging from 1 to 4 μm are widely used to excite the whispering-gallery(WG)modes of microcavities. Typically, the transmission spectrum of a WG cavity coupled to a waveguide around a res... Tapered fibers with diameters ranging from 1 to 4 μm are widely used to excite the whispering-gallery(WG)modes of microcavities. Typically, the transmission spectrum of a WG cavity coupled to a waveguide around a resonance assumes a Lorentzian dip morphology due to resonant absorption of the light within the cavity. In this paper, we demonstrate that the transmission spectra of a WG cavity coupled with an ultrathin fiber(500–700 nm)may exhibit both Lorentzian dips and peaks, depending on the gap between the fiber and the microcavity. By considering the large scattering loss of off-resonant light from the fiber within the coupling region, this phenomenon can be attributed to partially resonant light bypassing the lossy scattering region via WG modes, allowing it to be coupled both to and from the cavity, then manifesting as Lorentzian peaks within the transmission spectra.This implies the system could be implemented within a bandpass filter framework. 展开更多
关键词 WG Bandpass transmission spectra of a whisperinggallery microcavity coupled to an ultrathin fiber mode
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