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Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃ 被引量:1
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作者 Juntao Gao Zhiyun Wei +5 位作者 Mengke Yuan Zhe Wang Zhe Lü Qiang Li Lingling Xu Bo Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期600-609,I0013,共11页
Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)... Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for LT-SOFCs.Sm doping can significantly enhance the electrocata lytic activity and chemical stability of cathode.At 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious degradation.The remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi level.Moreover,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) resistivity.This work provides valuable guidance for systematic design of efficient and durable catalysts for LT-SOFCs. 展开更多
关键词 Low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance
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VSe_(2)/V_(2)C heterocatalyst with built-in electric field for efficient lithium-sulfur batteries:Remedies polysulfide shuttle and conversion kinetics
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作者 Yanwei Lv Lina Bai +7 位作者 Qi Jin Siyu Deng Xinzhi Ma Fengfeng Han Juan Wang Lirong Zhang Lili Wu Xitian Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期397-409,I0010,共14页
Lithium sulfur(Li-S)battery is a kind of burgeoning energy storage system with high energy density.However,the electrolyte-soluble intermediate lithium polysulfides(Li PSs)undergo notorious shuttle effect,which seriou... Lithium sulfur(Li-S)battery is a kind of burgeoning energy storage system with high energy density.However,the electrolyte-soluble intermediate lithium polysulfides(Li PSs)undergo notorious shuttle effect,which seriously hinders the commercialization of Li-S batteries.Herein,a unique VSe_(2)/V_(2)C heterostructure with local built-in electric field was rationally engineered from V_(2)C parent via a facile thermal selenization process.It exquisitely synergizes the strong affinity of V_(2)C with the effective electrocatalytic activity of VSe_(2).More importantly,the local built-in electric field at the heterointerface can sufficiently promote the electron/ion transport ability and eventually boost the conversion kinetics of sulfur species.The Li-S battery equipped with VSe_(2)/V_(2)C-CNTs-PP separator achieved an outstanding initial specific capacity of 1439.1 m A h g^(-1)with a high capacity retention of 73%after 100 cycles at0.1 C.More impressively,a wonderful capacity of 571.6 mA h g^(-1)was effectively maintained after 600cycles at 2 C with a capacity decay rate of 0.07%.Even under a sulfur loading of 4.8 mg cm^(-2),areal capacity still can be up to 5.6 m A h cm^(-2).In-situ Raman tests explicitly illustrate the effectiveness of VSe_(2)/V_(2)C-CNTs modifier in restricting Li PSs shuttle.Combined with density functional theory calculations,the underlying mechanism of VSe_(2)/V_(2)C heterostructure for remedying Li PSs shuttling and conversion kinetics was deciphered.The strategy of constructing VSe_(2)/V_(2)C heterocatalyst in this work proposes a universal protocol to design metal selenide-based separator modifier for Li-S battery.Besides,it opens an efficient avenue for the separator engineering of Li-S batteries. 展开更多
关键词 Li-S battery Shuttle effect Separator modifier VSe_(2)/V_(2)C heterostructure Built-in electric field
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Giant and controllable Goos—Hänchen shift of a reflective beam off a hyperbolic metasurface of polar crystals
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作者 薛天 李宇博 +5 位作者 宋浩元 王相光 张强 付淑芳 周胜 王选章 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期428-435,共8页
We conduct a theoretical analysis of the massive and tunable Goos–Hänchen(GH) shift on a polar crystal covered with periodical black phosphorus(BP)-patches in the THz range. The surface plasmon phonon polaritons... We conduct a theoretical analysis of the massive and tunable Goos–Hänchen(GH) shift on a polar crystal covered with periodical black phosphorus(BP)-patches in the THz range. The surface plasmon phonon polaritons(SPPPs), which are coupled by the surface phonon polaritons(SPh Ps) and surface plasmon polaritons(SPPs), can greatly increase GH shifts.Based on the in-plane anisotropy of BP, two typical metasurface models are designed and investigated. An enormous GH shift of about-7565.58 λ_(0) is achieved by adjusting the physical parameters of the BP-patches. In the designed metasurface structure, the maximum sensitivity accompanying large GH shifts can reach about 6.43 × 10^(8) λ_(0)/RIU, which is extremely sensitive to the size, carrier density, and layer number of BP. Compared with a traditional surface plasmon resonance sensor, the sensitivity is increased by at least two orders of magnitude. We believe that investigating metasurface-based SPPPs sensors could lead to high-sensitivity biochemical detection applications. 展开更多
关键词 Goos–H?nchen shift black phosphorus surface plasmon phonon polaritons sensitivity metasurfaces
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A new diatom genus Spargeria gen.nov.(Bacillariophyceae)from Xizang,China,and the description of two new species
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作者 Yan LIU John Patrick KOCIOLEK +5 位作者 Li WANG Xinxin LU Huan ZHU Guoxiang LIU Fengyang SUI Yawen FAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期291-303,共13页
During our investigation of diatom biodiversity in Xizang,two species exhibited unique morphological features discriminative from all previously known genera.Herein we describe these two species and describe as new th... During our investigation of diatom biodiversity in Xizang,two species exhibited unique morphological features discriminative from all previously known genera.Herein we describe these two species and describe as new the genus,Spargeria gen.nov.The new genus features narrow to wide rectangular valves,narrow valve mantles,filiform raphe branches that occur on the valve face only,terminal raphe fissures straight or slightly deflected to same side,bow-tie shaped central areas,chambered striae present on the valve face only,being absent from the mantle,wider striae near the axial area and very narrow near the margin,multiseriate striae with small and round areolae that are occluded externally.Comparatively,Spargeria zhuii sp.nov.has larger and robust valves,radiate striae,with one divergent stria near the apices,while Spargeria chenia sp.nov.is smaller,with narrow valves,striae slightly radiate in the middle,becoming convergent or parallel near apices.This new genus belongs to the family Pinnulariaceae,and it was compared and contrasted with other genera of this family.Our work suggests the need for continued studies to document the biodiversity of diatoms in Xizang. 展开更多
关键词 Spargeria new genus Pinnulariaceae morphology Xizang
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A generalization of Banach's lemma and its applications to perturbations of bounded linear operators
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作者 WANG Zi DING Jiu WANG Yu-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期363-369,共7页
Let X be a Banach space and let P:X→X be a bounded linear operator.Using an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear ... Let X be a Banach space and let P:X→X be a bounded linear operator.Using an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear operator on X,and a bound on its spectral radius is also obtained.This generalizes the classic Banach lemma.We apply the result to the perturbation analysis of general bounded linear operators on X with commutative perturbations. 展开更多
关键词 Banach lemma spectral radius generalized inverse perturbation analysis
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Atomic Dispersed Hetero‑Pairs for Enhanced Electrocatalytic CO_(2)Reduction
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作者 Zhaoyong Jin Meiqi Yang +13 位作者 Yilong Dong Xingcheng Ma Ying Wang Jiandong Wu Jinchang Fan Dewen Wang Rongshen Xi Xiao Zhao Tianyi Xu Jingxiang Zhao Lei Zhang David J.Singh Weitao Zheng Xiaoqiang Cui 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期55-67,共13页
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic activity.For example,in... Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic activity.For example,increasing the binding of the*COOH to the active site will generally increase the*CO desorption energy.Breaking this relationship may be expected to dramatically improve the intrinsic activity of CO_(2)RR,but remains an unsolved challenge.Herein,we addressed this conundrum by constructing a unique atomic dispersed hetero-pair consisting of Mo-Fe di-atoms anchored on N-doped carbon carrier.This system shows an unprecedented CO_(2)RR intrinsic activity with TOF of 3336 h−1,high selectivity toward CO production,Faradaic efficiency of 95.96%at−0.60 V and excellent stability.Theoretical calculations show that the Mo-Fe diatomic sites increased the*COOH intermediate adsorption energy by bridging adsorption of*COOH intermediates.At the same time,d-d orbital coupling in the Mo-Fe di-atom results in electron delocalization and facilitates desorption of*CO intermediates.Thus,the undesirable correlation between these steps is broken.This work provides a promising approach,specifically the use of di-atoms,for breaking unfavorable relationships based on understanding of the catalytic mechanisms at the atomic scale. 展开更多
关键词 CO_(2)reduction reaction Atomic dispersed catalyst Hetero-diatomic pair Ad-desorption energy Linear scaling relation
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Manipulating d-d orbital hybridization induced by Mo-doped Co_(9)S_(8) nanorod arrays for high-efficiency water electrolysis
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作者 Xue Zhou Jing Li +8 位作者 Guangyao Zhou Weiran Huang Yucan Zhang Jun Yang Huan Pang Mingyi Zhang Dongmei Sun Yawen Tang Lin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期592-600,I0015,共10页
Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic performance.Herein,we demonstrate an ingenious d-d orbital hybridization concept ... Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic performance.Herein,we demonstrate an ingenious d-d orbital hybridization concept to construct Mo-doped Co_(9)S_(8) nanorod arrays aligned on carbon cloth(CC)substrate(abbreviated as Mo-Co_(9)S_(8)@CC hereafter)as a high-efficiency bifunctional electrocatalyst toward water electrolysis.It has experimentally and theoretically validated that the 4d-3d orbital coupling between Mo dopant and Co site can effectively optimize the H_(2)O activation energy and lower H^(*)adsorption energy barrier,thereby leading to enhanced hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)activities.Thanks to the unique electronic and geometrical advantages,the optimized Mo-Co_(9)S_(8)@CC with appropriate Mo content exhibits outstanding bifunctional performance in alkaline solution,with the overpotentials of 75 and 234 mV for the delivery of a current density of 10 mA cm^(-2),small Tafel slopes of 53.8 and 39.9 mV dec~(-1)and long-term stabilities for at least 32 and 30 h for HER and OER,respectively.More impressively,a water splitting electrolylzer assembled by the self-supported Mo-Co_(9)S_(8)@CC electrode requires a low cell voltage of 1.53 V at 10 mA cm^(-2)and shows excellent stability and splendid reversibility,demonstrating a huge potential for affordable and scalable electrochemical H_(2) production.The innovational orbital hybridization strategy for electronic regulation herein provides an inspirable avenue for developing progressive electrocatalysts toward new energy systems. 展开更多
关键词 d-d orbital hybridization Transition metal sulfides Nanorods arrays Water electrolysis
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Analyzing and Forecasting Climate Change in Harbin City,Northeast China 被引量:4
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作者 ZHANG Lijuan LIU Dong +3 位作者 YAN Xiaodong ZHOU Dongying ZHENG Hong SU Lianling 《Chinese Geographical Science》 SCIE CSCD 2011年第1期65-73,共9页
Based on sounding data from 1975 to 2005 and TM/ETM+ remote sensing images in 1989, 2001 and 2007, the climate changes in Harbin City, Northeast China in recent 30 years were analyzed and forecasted. Results show that... Based on sounding data from 1975 to 2005 and TM/ETM+ remote sensing images in 1989, 2001 and 2007, the climate changes in Harbin City, Northeast China in recent 30 years were analyzed and forecasted. Results show that in the lower troposphere the meridional wind speed and mean annual wind speed decrease, and in the lower stratosphere the temperature decreases while the meridional wind speed increases significantly. In the study area, the climate is becoming warmer and wetter in the middle lower troposphere. The expansion of urban area has great effects on the surface air temperature and the wind speed, leading to the increase of the surface air temperature, the decrease of the surface wind speed, and the increase of the area of urban high temperature zone. The quantitative equations have been established among the surface air temperature, the carbon dioxide (CO2) concentration and the specific humidity (the water vapor content). It is predicted that the future increasing rate of the surface air temperature is 0.85℃/10yr if emission concentration of CO2 remains unchanged; if emission concentration of CO2 decreases to 75%, 50% and 25%, respectively, the surface air temperature will increase 0.65℃/10yr, 0.46℃/10yr and 0.27℃/10yr, respectively. The rise of the surface air temperature in the study area is higher than that of the global mean temperature forecasted by IPCC. 展开更多
关键词 中国东北地区 哈尔滨市 气候变化 预测 二氧化碳浓度 年平均风速 空气温度 城市面积
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Effects of Normalized Difference Vegetation Index and Related Wavebands′ Characteristics on Detecting Spatial Heterogeneity Using Variogram-based Analysis 被引量:4
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作者 WEN Zhaofei ZHANG Ce +5 位作者 ZHANG Shuqing DING Changhong LIU Chunyue PAN Xin LI Huapeng SUN Yan 《Chinese Geographical Science》 SCIE CSCD 2012年第2期188-195,共8页
Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multipli... Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multiplicity of spatial heterogeneity by using various environmental variables. How these variables affect their corresponding spatial heterogeneities, however, have received little attention. In this paper, we examined the effects of characteristics of normalized difference vegetation index (NDVI) and its related bands variable images, namely red and near infrared (NIR), on their corresponding spatial heterogeneity detection based on variogram models. In a coastal wetland region, two groups of study sites with distinct fractal vegetation cover were tested and analyzed. The results show that: 1) in high fractal vegetation cover (H-FVC) area, NDVI and NIR variables display a similar ability in detecting the spatial heterogeneity caused by vegetation growing status structure; 2) in low fractal vegetation cover (L-FVC) area, the NIR and red variables outperform NDVI in the survey of soil spatial heterogeneity; and 3) generally, NIR variable is ubiquitously applicable for vegetation spatial heterogeneity investigation in different fractal vegetation covers. Moreover, as variable selection for remote sensing applications should fully take the characteristics of variables and the study object into account, the proposed variogram analysis method can make the variable selection objectively and scientifically, especially in studies related to spatial heterogeneity using remotely sensed data. 展开更多
关键词 归一化植被指数 空间异质性 函数分析 段特征 检测 变差 指数和 植被覆盖度
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Features of Sand-dust Deposits in Harbin City,China 被引量:4
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作者 XIE Yuanyun ZHANG yan +2 位作者 HE Kui ZHOU Jia KANG Chunguo 《Chinese Geographical Science》 SCIE CSCD 2006年第4期327-333,共7页
From the sedimentologic view,this paper analyses the grain-size distribution and the chemical composition of the deposits from sand-dust storm,occurring in Harbin on March 20,2002.The result indicates that there exist... From the sedimentologic view,this paper analyses the grain-size distribution and the chemical composition of the deposits from sand-dust storm,occurring in Harbin on March 20,2002.The result indicates that there exist plentiful coarse matters in the sand-dust deposits in Harbin,and the sand-dust composition presents obvious three peak distribu-tion characteristics,indicating that the sand-dust in Harbin is composed of multi-origin components.The grain-size composition consists of silt(4-8Ф),accounting for 71.18% of the total,sand(>4Ф),21.70%,and clay(<8Ф),only 7.13%.The average grain size(Mz) is 5.14Ф.The chemical elements of the deposits are mainly SiO2 and Al2O3 and Fe2O3,totally occupying 77.8%.The enrichment factors(EF) of Mg,K,Si,Fe,Mn,P,Ti,Co,Ni and V elements are all about 1,which mainly come from lithosphere source,while parts of Cu,Pb,Zn,Cr and Se elements are from pollution sources out of lithosphere source,and As,Cd and Sb elements are mainly from pollution sources.Based on the com-prehensive analysis of grain-size,chemical composition,enrichment factor(EF),discriminant function(DF) and matter source index(PI),this paper points out that the grain-size distribution and element composition of the sand-dust deposits in Harbin are evidently different from the loess and sand-dust in Lanzhou,and that matter source of the sand-dust in Harbin is different from the loess in Northwest China and the sand-dust in Lanzhou.The sand-dust deposits in Harbin are an admixture of coarse grains transmitted in short distance and fine grains transported in long distance.The plentiful coarse grains of the sand-dust deposits in Harbin origin from sand of local spot,and are the near-source deposits transported by low altitude airflow. 展开更多
关键词 哈尔滨 沙尘暴沉积物 颗粒成分 粒度分布 化学成分
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Molecular phylogeny and ultrastructure of a new population of Urostyla grandis(Ciliophora, Hypotrichida) from Harbin, China
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作者 CAI Xinglong CHEN Ying +5 位作者 ZHAO Xiaolu GAO Jing Saleh A. AL-FARRAJ YU Lijie PAN Xuming QIU Zijian 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第1期256-265,共10页
A new population of Urostyla grandis, collected from a freshwater pond of northeastern China was investigated by living observation, silver impregnation, and molecular phylogeny based on small subunit ribosomal rRNA(S... A new population of Urostyla grandis, collected from a freshwater pond of northeastern China was investigated by living observation, silver impregnation, and molecular phylogeny based on small subunit ribosomal rRNA(SSU rRNA). Besides, its ultrastructural characteristics were investigated carefully by scanning electron microscopy(SEM) and transmission electron microscopy(TEM) methods.Complementary descriptions of some inner ultrastructures were provided and some new organelles were also found. Especially, the oral inner microtubule system was illustrated by SEM and TEM for the ?rst time and a new type extrusome was reported. These results may supply complement taxonomic data and ingestion mechanism on ciliates in genus Urostyla. 展开更多
关键词 Urostyla grandis phylogeny ULTRASTRUCTURE NEW POPULATION
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All-Climate Stretchable Dendrite-Free Zn-Ion Hybrid Supercapacitors Enabled by Hydrogel Electrolyte Engineering 被引量:3
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作者 Yuqi Jiang Kun Ma +2 位作者 Meiling Sun Yuanyuan Li Jinping Liu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期381-388,共8页
Hybrid supercapacitors have shown great potentials to fulfill the demand of future diverse applications such as electric vehicles and portable/wearable electronics.In particular,aqueous zinc-ion hybrid supercapacitors... Hybrid supercapacitors have shown great potentials to fulfill the demand of future diverse applications such as electric vehicles and portable/wearable electronics.In particular,aqueous zinc-ion hybrid supercapacitors(ZHSCs)have gained much attention due to their low-cost,high energy density,and environmental friendliness.Nevertheless,typical ZHSCs use Zn metal anode and normal liquid electrolyte,causing the dendrite issue,restricted working temperature,and inferior device flexibility.Herein,a novel flexible Zn-ion hybrid supercapacitor(FZHSC)is developed by using activated carbon(AC)anode,δ-MnO_(2) cathode,and innovative PVA-based gel electrolyte.In this design,heavy Zn anode and its dendrite issue are avoided and layered cathode with large interlayer spacing is employed.In addition,flexible electrodes are prepared and integrated with an anti-freezing,stretchable,and compressible hydrogel electrolyte,which is attained by simultaneously using glycerol additive and freezing/thawing technique to regulate the hydrogen bond and microstructure.The resulting FZHSC exhibits good rate capability,high energy density(47.86 Wh kg^(−1);3.94 mWh cm^(−3)),high power density(5.81 kW kg^(−1);480 mW cm^(−3)),and excellent cycling stability(~91%capacity retention after 30000 cycles).Furthermore,our FZHSC demonstrates outstanding flexibility with capacitance almost unchanged even after various continuous shape deformations.The hydrogel electrolyte still maintains high ionic conductivity at ultralow temperatures(≤−30℃),enabling the FZHSC cycled well,and powering electronic timer robustly within an all-climate temperature range of−30~80℃.This work highlights that the promising Zn metal-free aqueous ZHSCs can be designed with great multifunctionality for more practical application scenarios. 展开更多
关键词 all-climate operation dendrite-free anode high flexibility multifunctional gel electrolyte Zn-ion hybrid supercapacitor
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Flavonol synthase gene MsFLS13 regulates saline-alkali stress tolerance in alfalfa 被引量:1
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作者 Lishuang Zhang Yugang Sun +7 位作者 Jinqiang Ji Weidi Zhao Weileng Guo Jiaqi Li Yan Bai Dan Wang Zhe Yan Changhong Guo 《The Crop Journal》 SCIE CSCD 2023年第4期1218-1229,共12页
Alfalfa(Medicago sativa L.) is one of the most extensively grown leguminous forage worldwide.Environmental saline-alkali stress significantly influences the growth,development,and yield of alfalfa,posing a threat to i... Alfalfa(Medicago sativa L.) is one of the most extensively grown leguminous forage worldwide.Environmental saline-alkali stress significantly influences the growth,development,and yield of alfalfa,posing a threat to its agricultural production.However,little is known about the potential mechanisms by which alfalfa responds to saline-alkali stress.Here,we investigated these mechanisms by cloning a saline-alkali-induced flavonol synthase gene(Ms FLS13) from alfalfa,which was previously reported to be significantly upregulated under saline-alkali stress,and examining its function in the saline-alkali response.Overexpression of Ms FLS13 in alfalfa promoted plant tolerance to saline-alkali stress by enhancing flavonol accumulation,antioxidant capacity,osmotic balance,and photosynthetic efficiency.Conversely,Ms FLS13 inhibition using RNA interference reduced flavonol synthase activity and inhibited hairy root growth under saline-alkali stress.Yeast one-hybrid and dual-luciferase reporter assays indicated that the R2R3-MYB Ms MYB12 transcription factor activates Ms FLS13 expression by binding to the MBS motif in the Ms FLS13 promoter.Further analysis revealed that abscisic acid mediates the salinealkali stress response partially by inducing Ms MYB12 and Ms FLS13 expression,which consequently increases flavonol levels and maintains antioxidant homeostasis in alfalfa.Collectively,our findings highlight the crucial role of Ms FLS13 in alfalfa in response to saline-alkali stress and provide a novel genetic resource for creating saline-alkali-resistant alfalfa through genetic engineering. 展开更多
关键词 ALFALFA SALINE-ALKALI Msfls13 Msmyb12 ANTIOXIDANT
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Electrospun Semiconductor-Based Nano-Heterostructures for Photocatalytic Energy Conversion and Environmental Remediation:Opportunities and Challenges 被引量:2
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作者 Na Lu Mingyi Zhang +3 位作者 Xuedong Jing Peng Zhang Yongan Zhu Zhenyi Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期212-238,共27页
Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental pollution.Design and synthesis of nano-heterostr... Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental pollution.Design and synthesis of nano-heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic processes.Onedimensional(1D)semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter,high ratio of surface to volume,small grain sizes,and high porosity,which are ideally suited for photocatalytic reactions from the viewpoint of structure advantage.After the secondary treatment of these nanofibers through the solvothermal,gas reduction,in situ doping,or assembly methods,the multi-component nanofibers with hierarchical nano-heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic processes.In recent years,the electrospun semiconductorbased nano-heterostructures have become a“hot topic”in the fields of photocatalytic energy conversion and environmental remediation.This review article summarizes the recent progress in electrospinning synthesis of various kinds of high-performance semiconductor-based nano-heterostructure photocatalysts for H2 production,CO_(2) reduction,and decomposition of pollutants.The future perspectives of these materials are also discussed. 展开更多
关键词 electrospun nanofibers energy conversion environmental remediation PHOTOCATALYSIS semiconductor heterojunction
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Atomically dispersed Fe-Ni dual sites in heteroatom doped carbon tyres for efficient oxygen electrocatalysis in rechargeable Zn-Air battery 被引量:1
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作者 Zili Wang Caiyun Li +3 位作者 Yukun Liu Yu Wu Sen Zhang Chao Deng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期264-274,I0008,共12页
The electronic and functional synergies between the twin metal centers make dual single-atom catalysts(DACs) attractive for oxygen electrocatalysis. The catalytic activities of DACs are largely decided by their surrou... The electronic and functional synergies between the twin metal centers make dual single-atom catalysts(DACs) attractive for oxygen electrocatalysis. The catalytic activities of DACs are largely decided by their surrounding micro-environment and supporting substrates. Modulating the micro-environment as well as engineering the efficient support is challenging tasks. Moreover, both are critical to optimizing the performance of DACs. Herein, a novel bio-cooperative strategy is developed to synthesize Fe Ni-DAC wherein Fe-Ni dual-atom sites are embedded in the N, P codoped tyre shaped carbon matrix. The configuration matching of Fe-Ni dual centers together with the local electronic engineering of N, P heteroatoms synergistically boost the catalytic activity on the oxygen reaction. Furthermore, the central-hollow highlyporous carbon matrix not only gives rise to a large amount of active sites, but also facilitates fast kinetics.Taking advantage of both the DAC and the substrate, the Fe Ni-NPC hollow tyre(HT) catalyst scores high in both oxygen reduction and evolution reactions, which exhibits the narrow potential difference and excellent durability. The aqueous Zn-air full battery(ZAB) integrating the Fe Ni-NPC HT air cathode has a high power density and a good stability over long-term cycling. Moreover, the flexible solid-state ZAB assembled with the polymer electrolyte obtains the high reliability over a wide range of temperatures or under diverse outside deformations. Therefore, this work offers a new green approach to prepare highly efficient DACs with built-in modulated micro-environment and tailor-made substrates. Moreover,it also paves a new way to develop highly-pliable power source for flexible electronics. 展开更多
关键词 FeNi dual sites P N codoped carbon Bio-assisted stategy Zn-air battery
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Insights into cryptic speciation of quillworts in China 被引量:1
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作者 Yu-Feng Gu Jiang-Ping Shu +7 位作者 Yi-Jun Lu Hui Shen Wen Shao Yan Zhou Qi-Meng Sun Jian-Bing Chen Bao-Dong Liu Yue-Hong Yan 《Plant Diversity》 SCIE CAS CSCD 2023年第3期284-301,共18页
Cryptic species are commonly misidentified because of high morphological similarities to other species.One group of plants that may harbor large numbers of cryptic species is the quillworts(Isoetes spp.),an ancient aq... Cryptic species are commonly misidentified because of high morphological similarities to other species.One group of plants that may harbor large numbers of cryptic species is the quillworts(Isoetes spp.),an ancient aquatic plant lineage.Although over 350 species of Isoetes have been reported globally,only ten species have been recorded in China.The aim of this study is to better understand Isoetes species diversity in China.For this purpose,we systematically explored the phylogeny and evolution of Isoetes using complete chloroplast genome(plastome)data,spore morphology,chromosome number,genetic structure,and haplotypes of almost all Chinese Isoetes populations.We identified three ploidy levels of Isoetes in Chinaddiploid(2n=22),tetraploid(2n=44),and hexaploid(2n=66).We also found four megaspore and microspore ornamentation types in diploids,six in tetraploids,and three in hexaploids.Phylogenetic analyses confirmed that I.hypsophila as the ancestral group of the genus and revealed that Isoetes diploids,tetraploids,and hexaploids do not form monophyletic clades.Most individual species possess a single genetic structure;however,several samples have conflicting positions on the phylogenetic tree based on SNPs and the tree based on plastome data.All 36 samples shared 22 haplotypes.Divergence time analysis showed that I.hypsophila diverged in the early Eocene(~48.05 Ma),and most other Isoetes species diverged 3-20 Ma.Additionally,different species of Isoetes were found to inhabit different water systems and environments along the Yangtze River.These findings provide new insights into the relationships among Isoetes species in China,where highly similar morphologic populations may harbor many cryptic species. 展开更多
关键词 Plastid genome ISOETACEAE PHYLOGENY EVOLUTIONARY Divergence time
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Spatiotemporal Differences and Classification Regulation of Urbanization Impact on Agricultural Development in Shrinking Areas:A Case Study of 15 Shrinking Cities in Three Provinces of Northeast China
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作者 CHEN Xiaohong LIU Haihan +4 位作者 AN Yongle DAI Yue PAN Wei WANG Ying TANG We 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1053-1067,共15页
Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shri... Studying the impact of urbanization on agricultural development in shrinking areas is important for maintaining food security and promoted agricultural development in China.Based on the measurement results of the shrinking cities in the three provinces of Northeast China,this paper selects 15 shrinking cities as the research object,and constructs a multi-dimensional index system to explore the impact of the urbanization level of the shrinking areas on the agricultural development in the region since 2007–2019,analyzes the influencing factors and their differences by using the geographically-weighted regression model and Geodetector,and proposes a targeted regulation strategy.The results show that:1)overall,there is a negative correlation between the urbanization level and the agricultural development level in the contracted areas of the three northeastern provinces.The urbanization level in these areas has a certain negative impact on the overall level of agricultural development;2)regarding the time dimension,the impact of urbanization level on the agricultural development level in the contracted areas of the three northeastern provinces gradually increases over time;3)regarding the spatial pattern,the overall impact of shrinking urbanization levels in the three provinces of Northeast China on the agricultural development shows a significant distribution pattern of high in the east and low in the west;4)the total population and natural population growth rate at the end of the year were the main factors influencing a certain level of urbanization on agricultural development in the shrinking cities while population density and the urban fixed asset investment rate were the secondary factors;and 5)the main reasons why the level of agricultural development in different cities was affected by the level of urbanization were different.However,they can be categorized into areas of population loss and spatial construction,which can be further divided into area of population loss in the northeast,areas of negative population growth in the west,and areas of urban spatial change in the south.According to the causes of the impact,this paper adopted targeted regulation strategies and formulated relevant policies and solutions that cater to local conditions. 展开更多
关键词 URBANIZATION agricultural development classification and regulation shrinking cities three provinces of Northeast China
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A New Prediction System Based on Self-Growth Belief Rule Base with Interpretability Constraints
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作者 Yingmei Li Peng Han +3 位作者 Wei He Guangling Zhang Hongwei Wei Boying Zhao 《Computers, Materials & Continua》 SCIE EI 2023年第5期3761-3780,共20页
Prediction systems are an important aspect of intelligent decisions.In engineering practice,the complex system structure and the external environment cause many uncertain factors in the model,which influence the model... Prediction systems are an important aspect of intelligent decisions.In engineering practice,the complex system structure and the external environment cause many uncertain factors in the model,which influence the modeling accuracy of the model.The belief rule base(BRB)can implement nonlinear modeling and express a variety of uncertain information,including fuzziness,ignorance,randomness,etc.However,the BRB system also has two main problems:Firstly,modeling methods based on expert knowledge make it difficult to guarantee the model’s accuracy.Secondly,interpretability is not considered in the optimization process of current research,resulting in the destruction of the interpretability of BRB.To balance the accuracy and interpretability of the model,a self-growth belief rule basewith interpretability constraints(SBRB-I)is proposed.The reasoning process of the SBRB-I model is based on the evidence reasoning(ER)approach.Moreover,the self-growth learning strategy ensures effective cooperation between the datadriven model and the expert system.A case study showed that the accuracy and interpretability of the model could be guaranteed.The SBRB-I model has good application prospects in prediction systems. 展开更多
关键词 Belief rule base evidence reasoning interpretability optimization prediction system
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A Processor Performance Prediction Method Based on Interpretable Hierarchical Belief Rule Base and Sensitivity Analysis
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作者 Chen Wei-wei He Wei +3 位作者 Zhu Hai-long Zhou Guo-hui Mu Quan-qi Han Peng 《Computers, Materials & Continua》 SCIE EI 2023年第3期6119-6143,共25页
The prediction of processor performance has important referencesignificance for future processors. Both the accuracy and rationality of theprediction results are required. The hierarchical belief rule base (HBRB)can i... The prediction of processor performance has important referencesignificance for future processors. Both the accuracy and rationality of theprediction results are required. The hierarchical belief rule base (HBRB)can initially provide a solution to low prediction accuracy. However, theinterpretability of the model and the traceability of the results still warrantfurther investigation. Therefore, a processor performance prediction methodbased on interpretable hierarchical belief rule base (HBRB-I) and globalsensitivity analysis (GSA) is proposed. The method can yield more reliableprediction results. Evidence reasoning (ER) is firstly used to evaluate thehistorical data of the processor, followed by a performance prediction modelwith interpretability constraints that is constructed based on HBRB-I. Then,the whale optimization algorithm (WOA) is used to optimize the parameters.Furthermore, to test the interpretability of the performance predictionprocess, GSA is used to analyze the relationship between the input and thepredicted output indicators. Finally, based on the UCI database processordataset, the effectiveness and superiority of the method are verified. Accordingto our experiments, our prediction method generates more reliable andaccurate estimations than traditional models. 展开更多
关键词 Hierarchical belief rule base(HBRB) evidence reasoning(ER) INTERPRETABILITY global sensitivity analysis(GSA) whale optimization algorithm(WOA)
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Spin splitting of vortex beams on the surface of natural biaxial hyperbolic materials
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作者 梁红 宋浩元 +2 位作者 李宇博 于迪 付淑芳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期372-381,共10页
We investigated the spin splitting of vortex beam on the surface of biaxial natural hyperbolic materials(NHMs)rotated by an angle with respect to the incident plane. An obvious asymmetry of spatial shifts produced by ... We investigated the spin splitting of vortex beam on the surface of biaxial natural hyperbolic materials(NHMs)rotated by an angle with respect to the incident plane. An obvious asymmetry of spatial shifts produced by the left-handed circularly(LCP) component and right-handed circularly polarized(RCP) component is exhibited. We derived the analytical expression for in-and out-of-plane spatial shifts for each spin component of the vortex beam. The orientation angle of the optical axis plays a key role in the spin splitting between the two spin components, which can be reflected in the simple expressions for spatial shifts without the rotation angle. Based on an α-MoO_(3) biaxial NHM, the spatial shifts of the two spin components with the topological charge were investigated. As the topological charge increases, the spatial shifts also increase;in addition, a tiny spatial shift close to zero can be obtained if we control the incident frequency or the polarization of the reflected beams. It can also be concluded that the maximum of the spin splitting results from the LCP component at p-incidence and the RCP component at s-incidence in the RB-Ⅱ hyperbolic frequency band. The effect of the incident angle and the thickness of the α-MoO_(3) film on spin splitting is also considered. These results can be used for manipulating infrared radiation and optical detection. 展开更多
关键词 spin splitting hyperbolic material vortex beam orbital angular momentum
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