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Dust transport information and paleoclimatic changes revealed by the loess in Ranwu,south-eastern Xizang

Frontiers of Earth Science 2023年第4期17卷 956-969页

作者： Meihui PAN Huimin ZHAO anna YANG Yougui CHEN Chenlu li College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070China CAS Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences(CAS)Chengdu 610041China

The loess accumulation process has great potential to record patterns of atmospheric circulation change,paleoclimate,and paleoenvironmental ***-eastern Xizang is a climatically sensitive region and here,we analyze a loess profile at Ranwu in order to explore the processes and interactions of dust transport and paleoclimate evolution in the *** on parametric grain size end-member analysis,optically stimulated luminescence(OSL)dating,and environmental proxies we show that the Ranwu loess profile comprises five end members(EMs).EM1 represents the fine silt fraction transported by high-altitude westerly winds over long distances;EM2 represents the medium silt fraction accumulated by glacier winds;EM3 is the coarse silt fraction transported by local dust storms under the action of strong glacier winds;EM4 represents the very fine sand fraction transported by strong local dust storms,different wind strengths controls the relative proportion of EM3 and EM4 over ***5 is the coarse sand fraction formed from the product of strong weathering of *** dating shows loess sedimentation at Ranwu started around 11.16 *** prevailing climate was generally warm and wet between 11.6 and 4.2 ka,with four cooling events at 10.50,9.18,7.85,and 6.37 *** paleosol development between 8.2 and 4.2 ka,a change to dry and cold climate conditions was favorable for loess formation after 4.2 *** palaeoenvironmental changes and abrupt climate events recorded in the Ranwu loess sequence are consistent with Holocene global environmental changes.

关键词： loess grain size end member the optically stimulated luminescencethe dust transport information environmental evolution southeastern Xizang region

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Effects of a check dam system on the runoff generation and concentration processes of a catchment on the Loess Plateau

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International Soil and Water Conservation Research 2022年第1期10卷 86-98页

作者： Shuilong Yuan Zhanbin li li Chen Peng li Zeyu Zhang Junzheng Zhang anna Wang kunxia Yu State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an710048ShaanxiChina Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an University of TechnologyXi'an710048ShaanxiChina Desert Research Institute Las VegasNV89012USA Institute of Soil and Water Conservation Investigation and Planning of Shaanxi Province Xi'an710100ShaanxiChina

As an important soil and water conservation engineering measure,more than 100,000 check dams are constructed across the Loess Plateau;these dams play a vital role in reducing floods and sediment in the ***,the effects of check dams on hydrologic process are still unclear,particularly when they are deployed as a system for watershed soil and water *** study examined the watershed hydrologic process modulated by the check dam system in a typical Loess Plateau *** simulating scenarios with various numbers of check dams using a distributed physically-based hydro-logical model,the effects of the number of check dams on runoff generation and concentration were analyzed for the study *** results showed that the presence of check dams reduced the peak discharge and the flood volume and extended the flood duration;the reduction effect on peak discharge was most significant among the three *** system of check dams substantially decreased the runoff coefficient,and the runoff coefficient reduction rate was greater for rainstorms with shorter return periods than for rainstorms with longer return *** check dams increased the capacity of the catchment regulating and storing floods and extended the average runoff concentration time in the catchment that flattened the instantaneous unit *** study reveals the influencing mech-anism of check dam system on the watershed hydrological process under heavy rainstorm conditions and provides a theoretical basis for evaluating the effects of numerous check dams on regional hydrology and water resources on the Loess Plateau.

关键词： Check dam system Runoff generation Runoff concentration Instantaneous unit hydrograph Loess Plateau

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Carotenoid Pigment Accumulation in Horticultural Plants

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Horticultural Plant Journal 2020年第6期6卷 343-360页

作者： anna S.Hermanns Xuesong Zhou Qiang Xu Yaakov Tadmor li li Plant Breeding and Genetics Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA Robert W.Holley Center for Agriculture and Health USDA-Agricultural Research ServiceCornell UniversityIthacaNY 14853USA State Key Laboratory of Crop Genetics&Germplasm Enhancement Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Horticultural Plant Biology(Ministry of Education) Huazhong Agricultural UniversityWuhan 430070China Department of Vegetable Research ARONewe Ya’ar Research CenterP.O.Box 1021Ramat Yishay 30095Israel

Carotenoids are a group of widely distributed natural *** give many horticultural plants the bright red,orange,and yellow colors,as well as the aroma and *** enhance the health value and represent an essential quality trait of horticultural *** efforts have been made to correlate specific carotenoid production with pathway gene *** transcription factors that directly regulate transcription of the pathway genes have been *** crops have evolved with complicated and multifaceted regulatory mechanisms to generate the enormous diversity in carotenoid content and ***,the diverse and complex control of carotenoid accumulation is still not well *** this review,we depict carotenoid accumulation pathways and highlight the recent progress in the regulatory control of carotenoid accumulation in horticultural *** of the critical roles of chromoplasts for carotenoid hyperproduction,we evaluate chromoplast ultrastructures and carotenoid sequestrations.A perspective on carotenoid research in horticultural crops is provided.

关键词： Carotenoid Chromoplast Pathway Regulation Horticultural crops

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P-glycoprotein(ABCB1)-weak dipolar interactions provide the key to understanding allocrite recognition,binding,and transport

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Cancer Drug Resistance 2023年第1期6卷 1-29页

作者： anna Seelig Xiaochun li-Blatter Biozentrum University of BaselBasel 4056Switzerland

P-glycoprotein(ABCB1)is the first discovered mammalian member of the large family of ATP binding cassette(ABC)*** facilitates the movement of compounds(called allocrites)across membranes,using the energy of ATP binding and ***,we review the thermodynamics of allocrite binding and the kinetics of ATP hydrolysis by *** combination with our previous molecular dynamics simulations,these data lead to a new model for allocrite transport by *** contrast to previous models,we take into account that the transporter was evolutionarily optimized to operate within a membrane,which dictates the nature of *** interactions drive lipid-water partitioning of allocrites,the transport process’s first *** dipolar interactions(including hydrogen bonding,π-π stacking,and π-cation interactions)drive allocrite recognition,binding,and transport by ABCB1 within the *** the lateral membrane packing density reduces allocrite partitioning but enhances dipolar interactions between allocrites and *** flopping(or reorientation of the polar part towards the extracellular aqueous phase)occurs after hydrolysis of one ATP molecule and opening of ABCB1 at the extracellular *** of ATP re-closes the transporter at the extracellular side and expels the potentially remaining allocrite into the *** high sensitivity of the steady-state ATP hydrolysis rate to the nature and number of dipolar interactions,as well as to the dielectric constant of the membrane,points to a flopping process,which occurs to a large extent at the membrane-transporter *** proposed unidirectional ABCB1 transport cycle,driven by weak dipolar interactions,is consistent with membrane biophysics.

关键词： Catalytic cycle hydrogen bond π-electron donor polyspecificity amphiphilicity stoichiometry

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Vicinal hydroxyl group-inspired selective oxidation of glycerol to glyceric acid on hydroxyapatite supported Pd catalyst

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Green Energy & Environment 2022年第4期7卷 691-703页

作者： Difan li Xiuge Zhao Qingqing Zhou Bingjie Ding anna Zheng Qingpo Peng Zhenshan Hou Key Laboratory for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Selective oxidation of glycerol provides a feasible route towards the sustainable synthesis of high value-added ***,the hydroxyapatite(HAP)supported palladium(Pd)species were fabricated by impregnation and subsequent *** as-obtained heterogeneous Pd catalyst afforded not only excellent selectivity to glyceric acid(GLA)up to 90%with 59%conversion of glycerol but also good recyclability by using molecular oxygen as an oxidant under mild *** characterization of catalysts indicated that both the surface basicity and Pd sites on the catalyst played a crucial role in promoting glycerol ***,it demonstrated that the presence of the vicinal hydroxyl group of glycerol molecule can assist the oxidation reaction via forming a coordination between the vicinal hydroxyl group and Ca^(2+) sites on HAP-derived *** this catalytic process,the secondary hydroxyl of glycerol kept untouched and the primary hydroxyl of glycerol was converted into carboxyl group,while the Pd species acted as active centers for cooperatively promoting the subsequent oxidation to generate ***,this catalytic system can be extended widely for the oxidative conversion of other vicinal diols into the corresponding a-hydroxycarboxylic acids *** labeling experiment using H_(2)^(18)O confirmed that H_(2)O not only acted as solvent but also was involved in the catalytic *** the basis of the results,a possible reaction mechanism has been *** HAP-supported Pd catalytic system has been shown to serve as an effective approach for the upgrading of bio-derived vicinal diols to high value-added chemicals.

关键词： Hydroxyapatite Palladium Glycerol oxidation Glyceric acid Vicinal hydroxyl group

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Homogenised Monthly and Daily Temperature and Precipitation Time Series in China and Greece since 1960

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Advances in Atmospheric Sciences 2023年第7期40卷 1326-1336页

作者： Athanassios A.ARGIRIOU Zhen li Vasileios ARMAOS anna MAMARA Yingling SHI Zhongwei YAN Laboratory of Atmospheric Physics Department of PhysicsUniversity of PatrasRio 26504Greece Key Laboratory of Regional Climate-Environment in Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Hellenic National Meteorological Service Athens 16777Greece Longyang District Meteorological Service Baoshan 678007China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

In this paper,we describe and analyze two datasets entitled“Homogenised monthly and daily temperature and precipitation time series in China during 1960–2021”and“Homogenised monthly and daily temperature and precipitation time series in Greece during 1960–2010”.These datasets provide the homogenised monthly and daily mean(TG),minimum(TN),and maximum(TX)temperature and precipitation(RR)records since 1960 at 366 stations in China and 56stations in *** datasets are available at the Science Data Bank repository and can be downloaded from https://***/10.57760/sciencedb.01731 and https://***/10.57760/*** China,the regional mean annual TG,TX,TN,and RR series during 1960–2021 showed significant warming or increasing trends of 0.27℃(10 yr)^(-1),0.22℃(10 yr)^(-1),0.35℃(10 yr)^(-1),and 6.81 mm(10 yr)-1,*** of the seasonal series revealed trends significant at the 0.05level,except for the spring,summer,and autumn RR *** Greece,there were increasing trends of 0.09℃(10 yr)-1,0.08℃(10 yr)^(-1),and 0.11℃(10 yr)^(-1)for the annual TG,TX,and TN series,respectively,while a decreasing trend of–23.35 mm(10 yr)^(-1)was present for *** seasonal trends showed a significant warming rate for summer,but no significant changes were noted for spring(except for TN),autumn,and *** RR,only the winter time series displayed a statistically significant and robust trend[–15.82 mm(10 yr)^(-1)].The final homogenised temperature and precipitation time series for both China and Greece provide a better representation of the large-scale pattern of climate change over the past decades and provide a quality information source for climatological analyses.

关键词： daily and monthly temperature precipitation homogenisation climate time series Greece China

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Cyclicity of the Lower Buntsandstein in the eastern part of the Central European Basin:implications for Early Triassic palaeogeography and for geochronological calibration

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Journal of Palaeogeography 2024年第2期13卷 252-292页

作者： anna Becker Polish Geological Institute-National Research Institute 4 Rakowiecka str.00-975 WarsawPoland

Lower Buntsandstein small—scale cycles recognized in the Central European Basin(CEB) are readily used for astrochronological calibration of the Early Triassic time scales,although they are not well studied *** borehole sections from the eastern part of the CEB,forming a south-north transect perpendicular to the basin axis,were studied in terms to better understand the depositional history of the Lower Buntsandstein developed as the Baltic Formation in the studied Polish part of the *** sedimentary facies were recognized,based on lithological and sedimentological investigations of 655.7 m of drill cores from the Otyń IG 1,Gorzów Wielkopolski IG 1 and Kamień Pomorski IG 1 *** facies can be grouped according to a lithological criterion into facies of predominantly siliciclastic lithology(including 9facies types) and facies of predominantly carbonate lithology(including 2 facies types).Facies analysis allowed to distinguish 8 facies associations of:1) alluvial fan,2) playa,3) sandy-muddy coastal plain,4)embayment and distal delta,5) lagoon,6) sand bars or shoals,7) ooidal shoals or bars,and 8) ***-upward(DC) and shallowing-upward(SC) sedimentary cycles were recognized in parts of the Baltic Formation,with DCs dominating in the southernmost located Otyń IG 1,and SCs dominating in Gorz ow Wielkopolski IG 1,located in the axial part of the *** cycles are very *** statistical significance of the sedimentary cycles is relatively low according to Markov-chain analysis conducted with the phpSedistat software of Stanova et al.(2009).Analysis of small—scale cycles performed on well logs of investigated boreholes and additional boreholes in the vicinity of Otyń IG 1,implementing the earlier study of Becker(2005),showed that the correlation of well-log cycles(GR cycles) and sedimentary cycles is not *** cycles can be roughly correlated with lithological carbonate—siliciclastic cycles(c-s cycles),refle

关键词： Triassic Lower Buntsandstein Cyclicity Central European Basin

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Cornea modelling

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Eye and Vision 2020年第1期7卷 11-25页

作者： anna Pandolfi Department of Civil and Environmental Engineering Politecnico di MilanoPiazza Leonardo da Vinci 3220133 MilanoItaly

Background:Biomechanics introduces numerous technologies to support clinical practice in ophthalmology,with the goal of improving surgical outcomes and to develop new advanced technologies with minimum impact on clinical ***,a few misconceptions on the way that computational methods should be applied to living tissues contributes to a lack of confidence towards computer-based ***:Corneal biomechanics relies on sound theories of mechanics,including concepts of equilibrium,geometrical measurements,and complex material *** peculiarities of biological tissues require the consideration of multi-physics,typical of the eye environment,and to adopt customized geometrical models constructed on the basis of advanced optical imaging and in-vivo ***:Patient-specific models are able to predict the outcomes of refractive surgery and to exploit the results of in-vivo test to characterize the material properties of the corneal ***:Corneal biomechanics can become an important support to clinical practice,provided that methods are based on the actual multi-physics and use customized geometrical and mechanical models.

关键词： Corneal biomechanics Physiologic configuration Tonometry modelling Refractive surgery modelling

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Solar hydrogen production from electrochemical ammonia splitting powered by a single perovskite solar cell

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Journal of Energy Chemistry 2024年第5期92卷 292-295页

作者： anna MBeiler Wenhui li Alisa Denisiuk Emilio Palomares Antoni Llobet Institute of Chemical Research of Catalonia(ICIQ).Barcelona Institute of Science and Technology(BIST) 43007 TarragonaSpain Catalan Institution for Research and Advanced Studies(ICREA) 08010 BarcelonaSpain Departament de Química Universitat Autònoma de BarcelonaCerdanyola del Vallès08193 BarcelonaSpain

For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable *** solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting *** of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia *** this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular *** device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied *** work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.

关键词： Ammonia oxidation Redox catalysis Perovskites Solarfuels Transitionmetal complexes

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Joint power and spectrum allocation algorithm in cognitive radio networks

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Journal of Systems Engineering and Electronics 2011年第4期22卷 691-701页

作者： anna Auguste Anghuwo Communication Research Center Harbin Institute of Technology

The spectrum sharing problem between primary and cognitive users is mainly investigated. Since the interference for primary users and the total power for cognitive users are constrained, based on the well-known water-filling theorem, a novel one-user water-filling algorithm is proposed, and then the corresponding simulation results are given to analyze the feasibility and validity. After that this algorithm is used to solve the communication utility optimization problem subject to the power constraints in cognitive radio network. First, through the gain to noise ratio for cognitive users, a subcarrier and power allocation algorithm based on the optimal frequency partition is proposed for two cognitive users. Then the spectrum sharing algorithm is extended to multiuser conditions such that the greedy and parallel algorithms are proposed for spectrum sharing. Theory and simulation analysis show that the subcarrier and power allocation algorithms can not only protect the primary users but also effectively solve the spectrum and power allocation problem for cognitive users.

关键词： cognitive radio spectrum sharing water-filling algo-rithm interference constraint communication overhead.

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