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Prospects of sediment deposition at small watershed scale in the black soil region of Northeast China: A mini review

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Pedosphere 2024年第1期34卷 30-35页

作者： Guanghui ZHANG yang yang Yingna LIU Zhiqiang WANG State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Sediment deposition is one of the most significant processes in small watersheds characterized by gentle long hillslopes in the black soil(Mollisol)region of Northeast China, as indicated by severe ephemeral gully and gully erosion on hillslopes and very low sediment concentrations in river *** reviews have been conducted to summarize the related research in this region. The objectives of this review were to identify the potential factors influencing sediment deposition, review related studies, and propose future research needs in the black soil region of Northeast China. Sediment deposition is controlled by the deficit between sediment transport capacity of flow and sediment load. Hence, all factors affecting flow transport capacity and sediment load directly affect sediment deposition. For a specific small watershed, the change in slope gradient along the flow path is the key factor affecting sediment deposition. Shelterbelts, ridge tillage systems, terraces, grass strips, road distribution, ponds and reservoirs, and land-use patterns also influence the spatial distribution and rate of deposition. The trace method has been widely used to quantify sediment deposition in this region. The results of cesium-137(^(137)Cs),lead-210(^(210)Pb), and magnetic susceptibility reveal that serious deposition occurs on the back and foot slopes. Distinct deposition occurs in front of contour shelterbelts. Future studies should focus on the methodology, spatial and temporal variations, dominant influencing factors and their mechanisms, and the potential effects on land productivity within specific small watersheds and across the black soil region. This review provides insights into the sediment deposition process in small watersheds characterized by gentle, long hillslopes.

关键词： Mollisol sedimentation soil and water conservation soil erosion soil redistribution

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Influence of Real Gas Properties on Aerodynamic Losses in a Supercritical CO2 Centrifugal Compressor

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Journal of Thermal Science 2024年第6期33卷 2032-2046页

作者： yang Mingyang CAI Ruikai ZHUGE Weilin yang Bijie ZHANG yangjun School of Mechanical Engineering Shanghai Jiao Tong University School of Vehicle and Mobility State Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua University Department of Mechanical Engineering Imperial College London

Supercritical carbon dioxide（SCO2） centrifugal compressor is a key component of a closed Brayton cycle system based on SCO2.A comprehensive understanding of the loss mechanism within the compressor is vital for its optimized ***,the physical properties of SCO2are highly nonlinear near the critical point,and the internal flow of the compressor is closely related to its properties,which inevitably influences the generation of aerodynamic losses within the *** paper presents a comprehensive investigation of the compressor's loss mechanism with an experimentally validated numerical *** real gas model of CO2embodied in the Reynolds-Averaged Navier-Stokes（RANS） model was used for the ***,the numerical simulation method was validated against the experimental results of Sandia ***,performance and loss distribution of the compressor were compared among three fluids including SCO2,ideal CO2（ICO2） and ideal air（IAir）.The results showed that the performance of SCO2was comparable to IAir under low flow coefficient,however markedly inferior to the other two fluids at near choke *** distribution among the three fluids was *** the impeller,SCO2was the most inefficient,followed by ICO2and *** discrepancies were magnified as the flow coefficient *** is due to a stronger Blade-to-Blade pressure gradient that intensifies boundary layer accumulation on walls of the shroud/***,owing to the reduced sonic speed of SCO2,a shock wave appears earlier at the throat region and SCO2encounters more intense boundary layer separation.

关键词： centrifugal compressor loss mechanism real gas properties SCO2

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Fiducial Approach for the Storage Reliability Assessment of Complex Repairable Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1653-1671页

作者： yang yang ZHAO Letian CHEN Siyi YU Dan University of Chinese Academy of Sciences Beijing 100190China Computer Application Institute of Nuclear Industry Beijing 100142China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

In recent years,there has been a growing focus on high-reliability products in industrial and military *** plays a crucial role in these products,and as a result,research on storage reliability has gained more *** paper specifically targets a class of products with complex structures that require long-term storage,regular testing,and ***,an expression method for system availability is provided based on the reliability structure of the system and the maintenance situation of the constituent equipment in *** the expression of system availability is typically complex and difficult to compute,and the storage life of the system cannot be represented as an explicit function of the reliability indicators of the constituent equipment,it is challenging to evaluate the availability and storage life of repairable *** address this,the paper proposes a comprehensive evaluation methodology for assessing the storage reliability of complex repairable systems based on fiducial *** approach is employed to derive point estimates and determine the lower fiducial limits for both system availability and storage ***,simulation results demonstrate that this comprehensive evaluation method for storage reliability of complex repairable systems is not only convenient but also highly effective.

关键词： Availability fiducial method repairable system storage life

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The role of exosomes in adult neurogenesis:implications for neurodegenerative diseases

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Neural Regeneration Research 2024年第2期19卷 282-288页

作者： Zhuoyang Yu Yan Teng Jing yang Lu yang Institute of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Laboratory of Aging Research School of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina

Exosomes are cup-shaped extracellular vesicles with a lipid bilayer that is approximately 30 to 200 nm in *** are widely distributed in a range of body fluids,including urine,blood,milk,and *** exert biological function by transporting factors between different cells and by regulating biological pathways in recipient *** an important form of intercellular communication,exosomes are increasingly being investigated due to their ability to transfer bioactive molecules such as lipids,proteins,mRNAs,and microRNAs between cells,and because they can regulate physiological and pathological processes in the central nervous *** neurogenesis is a multistage process by which new neurons are generated and migrate to be integrated into existing neuronal *** the adult brain,neurogenesis is mainly localized in two specialized niches:the subventricular zone adjacent to the lateral ventricles and the subgranular zone of the dentate *** increasing body of evidence indicates that adult neurogenesis is tightly controlled by environmental conditions with the *** recent studies,exosomes released from different sources of cells were shown to play an active role in regulating neurogenesis both in vitro and in vivo,thereby participating in the progression of neurodegenerative disorders in patients and in various disease ***,we provide a state-of-the-art synopsis of existing research that aimed to identify the diverse components of exosome cargoes and elucidate the therapeutic potential of exosomal contents in the regulation of neurogenesis in several neurodegenerative *** emphasize that exosomal cargoes could serve as a potential biomarker to monitor functional neurogenesis in *** addition,exosomes can also be considered as a novel therapeutic approach to treat various neurodegenerative disorders by improving endogenous neurogenesis to mitigate neuronal loss in the central nervous system.

关键词： adult neurogenesis Alzheimer’s disease amyotrophic lateral sclerosis exosome Huntington’s disease neurodegenerative disease neurogenic niches Parkinson’s disease

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Research progresses and prospects of multi-sphere compound extremes from the Earth System perspective

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Science China Earth Sciences 2024年第2期67卷 343-374页

作者： Zengchao HAO yang CHEN College of Water Sciences Beijing Normal UniversityBeijing100875China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing100081China

Compound extremes,whose socioeconomic and ecological impacts are severer than that caused by each event occurring in isolation,have evolved into a hot topic in Earth Science in the past *** the context of climate change,many compound extremes have exhibited increasing frequency and intensity,and shown novel fashions of combinations,posing more pressing demands and tougher challenges to scientific research and disaster prevention and *** article,via a perspective of multi-sphere interactions within the Earth System,systematically reviews the status quo,new scientific understanding,and deficiencies regarding the definition,mechanism,change,attribution,and projection of compound *** study also sorts out existing challenges and outlines a potential roadmap in advancing the study on compound extremes with respect to data requirement,mechanistic diagnosis,numerical modeling,attribution and projection,risk assessment,and adaptive *** directions of compound extremes studies and key research topics that warrant multi-disciplinary and multisectoral coordinated efforts are also *** that climate change has reshaped the type of extremes,a transformation from the traditional single-event perspective to a compound-event perspective is needed for scientific research,disaster prevention and mitigation,and climate change adaptation,calling for bottom-up innovation in research objects,ideas,and *** article will add value to promoting the research on compound extremes and interdisciplinary cooperations.

关键词： Extremes Compound extremes Climate change and risk Multi-sphere interactions

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Sm^(2+)ions boost ammonia electrooxidation reaction on samarium oxide anode for hydrogen generation in non-aqueous electrolyte

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Nano Research 2024年第7期17卷 5856-5862页

作者： Xingyu Liu Xue yang Han Sun Zekai yang Haijun Chen Tianjin Key Laboratory of Optoelectronic Thin Film Devices and Technology College of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and *** address the challenges associated with the direct usage of ammonia,the development of NH_(3)-to-H_(2)conversion technologies has emerged as a promising and effective ***,we present for the first time that crystallized Sm_(2)O_(3−x)electrodes demonstrate high and stable electrocatalytic activities,including N_(2)evolution rate and Faradaic efficiency,for ammonia electrolysis in a non-aqueous *** was observed that Sm^(2+)ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the ***,the mechanism of ammonia electrooxidation has also been elucidated,laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H_(2).

关键词： NH_(3)-to-N_(2)conversion ammonia electrooxidation reaction ammonia electrolysis non-aqueous electrolyte samarium oxide

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Crystalline-amorphous M@MN_x(M=Co,Fe,Ni)encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： yang yang Xiao-Chuan Duan Shao-Hui Guo Xian-Ming Zhang College of Materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developing earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is important for the sustainable energy ***,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MN_(x)(M=Co,Fe,Ni)encapsulated in N-doped carbon layers supported with N-doped graphene sheets(denoted as M@MN_(x)@NC-NG)are synthesized by facile hydrothermal reaction and nitridation *** the nitriding process,metal ions in M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)benzoic acid)complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MN_(x)shells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon(NC)layers that connect with inner MN_(x)via M-N-C motifs inherited from the complex precursors and inhibit the transition of MN_(x)from amorphous to crystalline *** Co@CoN_(x)@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm^(-2)and low Tafel slopes of 40 and 85 mV·dec^(-1)in 0.5 mol·L^(-1)H_(2)SO_4 and1.0 mol·L^(-1)KOH electrolytes,*** Co@CoN_(x)@NC-NG retains 97%of the initial overpotential after 100,000 s in both acidic and alkaline *** outstanding HER performance originates from the crystalline-amorphous Co@CoN_(x)that redistributes electrons around the heterointerfaces,facilitating the conversion process of H^(+)/H_(2)O to hydrogen and thereby promoting HER *** outermost NC layers serve as the armor of Co@CoN_(x),and graphene nanosheets act as carriers of egg-like Co@CoN_(x)@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure

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RMPC-Based Visual Servoing for Trajectory Tracking of Quadrotor UAVs With Visibility Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2027-2029页

作者： Qifan yang Huiping Li School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebase... 详细信息

关键词： Visual image visibility

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Chiral liquid crystal elastomers advance light modulation

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Light(Science & Applications) 2024年第9期13卷 1698-1700页

作者： Jiazhe Ma Zhongqiang yang Department of Chemistry Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of EducationTsinghua UniversityBeijing 100084China Laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Chiral liquid crystal elastomers,as soft photonic materials,enable dynamic omnidirectional tuning of circularly polarized reflection wavelength and function as an effective medium for full-color circularly polarized l... 详细信息

关键词： Chiral crystal circular

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Deficiency of Trp53 and Rb1 in myeloid cell lineage spontaneously develops acute myeloid leukemia in a mouse model

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Genes & Diseases 2024年第1期11卷 4-6页

作者： yang Li Shu-ting yang Shuying yang Department of Basic&Translational Sciences School of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Orthopaedic Surgery School of MedicineJohns Hopkins University BaltimoreMD 21205USA Center for Innovation&Precision Dentistry School of Dental MedicineSchool of Engineering and Applied SciencesUniversity of PennsylvaniaPhiladelphiaPA 19104USA The Penn Center for Musculoskeletal Disorders School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

Acute myeloid leukemia(AML)is a rapidly lethal blood cancer characterized by aberrant proliferation and differentiation of myeloid progenitors in the hematopoietic *** recent decades,AML patients are significantly *** 2019 alone,21,450 new AML cases were diagnosed in the United States,with an estimated 10,920 deaths due to ***’s worse,AML occurs with an increasing incidence with advanced age,and the survival rate remains dismal with a median overall survival of only 5e10 *** great advances in allogenic transplant and chemotherapy,the therapeutic outcomes are unfavorable due to the disease relapse and mortality *** importantly,the development of more specific and effective therapies was hampered in part by the lack of proper animal models for ***,management and elucidation of the pathological mechanism of AML remain an ongoing challenge,and the development of effective AML mouse models and treatment options are urgently needed.

关键词： myeloid Acute leukemia

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