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Late spring-early summer drought and soil properties jointly modulate two pine species' decline and climatic sensitivity in temperate Northern China

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FOREST ECOSYSTEMS 2025年第1期12卷 146-158页

作者： li, Yuheng Fan, Zhaofei Xu, lihong Zhang, Xiao Shi, Zhongjie Yang, Xiaohui Xiong, Wei Cong, ling Kwon, Semyun Pan, Leilei li, Hanzhi Wen, Shuo shang, Xiaoyan Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Chinese Acad Forestry Res Inst Ecol Conservat & Restorat Beijing 100091 Peoples R China Chinese Acad Forestry Res Inst Desertificat Studies Beijing 100091 Peoples R China Auburn Univ Coll Forestry Wildlife & Environm Auburn AL 36849 USA Chinese Acad Forestry Ecol & Nat Conservat Inst Beijing 100091 Peoples R China Kongju Natl Univ Inst Ecol Restorat Gongju 32439 Chungcheongnam South Korea Univ Chinese Acad Sci Beijing 100049 Peoples R China

Increasing temperatures and severe droughts threaten forest vitality globally. Prediction of forest response to climate change requires knowledge of the spatiotemporal patterns of monthly or seasonal climatic impacts on the growth of tree species, likely driven by local climatic aridity, climate trends, edaphic conditions, and the climatic adaption of tree species. The ability of tree species to cope with changing climate and the effects of environmental variables on growth trends and growth-climate relationships across diverse bioclimatic regions are still poorly understood for many species. This study investigated radial growth trends, interannual growth variability, and growth-climate sensitivity of two dominant tree species, Pinus tabulaeformis (PT) and Pinus sylvestris var. mongolica (PS), across a broad climatic gradient with a variety of soil properties in temperate Northern China. Using a network of 83 tree ring chronologies (54 for PT and 29 for PS) from 1971 to 2010, we documented that both species maintained constant growth trends at wet sites, while both displayed rapid declines at dry sites. We reported the species-specific drivers of spatial heterogeneity in growth trends, interannual growth variability, and growth-climate relationships. Calculated climatic variables and soil properties were identified as the most critical factors affecting the growth trends and growth-climate relationships. However, climatic variables play more essential roles than soil properties in determining the spatial heterogeneity of the growth-climate relationship. Lower clay content and higher soil nutrient regimes can exacerbate the moisture-related susceptibility of tree growth. Our findings highlight that soil properties emerged as important modulating factors to predict the drought vulnerability of forests in addition to climatic variables. Considering the continued climate warmingdrying trend in the future, both pines will face a more severe growth decline and increase i

关键词： Tree rings Climate sensitivity Growth decline Global warming Drought Soil property

A bio-inspired optical imaging method for robotic perception in turbid water

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Science China(Technological Sciences) 2025年第1期68卷 75-77页

作者： Xudong SUN Yafeng li Peng liN Xiaodi shang Xianping FU School of Information Science and Technology Dalian Maritime UniversityDalian 116026China College of Computer Science and Technology Qingdao UniversityQingdao 266071China

In the realm of underwater robotics,optical imaging plays a pivotal role in many scientific *** to the effects of absorption and scattering,images captured in turbid water are severely ***,enhancing the quality of underwater optical images stands paramount in ensuring the continued advancement and efficacy of underwater robots across its multifarious applications.

关键词： underwater optical continued

Electrocatalytic nitrite reduction to ammonia on isolated bismuth alloyed ruthenium

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Journal of Energy Chemistry 2025年第1期100卷 369-376页

作者： Shiyao shang Fuzhou Wang Zeyi Sun Chaofan Qiang Ke Chu School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070GansuChina

Electrochemical reduction of NO_(2)-to NH_(3)(NO_(2)-RR) is recognized as an appealing approach for achieving renewable NH_(3)synthesis and waste NO_(2)-***,we report isolated Bi alloyed Ru (Bi1Ru) as an efficient NO_(2)-RR *** calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO_(2)-activation and suppress proton adsorption,while accelerating the NO_(2)-RR protonation energetics to render a high NO_(2)--to-NH_(3)conversion ***,Bi1Ru assembled in a flow cell delivers an NH_(3)yield rate of 1901.4μmol h^(-1)cm^(-2)and an NH_(3)-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA cm^(-2).This study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO_(2)-RR catalysts toward the ammonia electrosynthesis.

关键词： Electrocatalytic reduction of NO_(2)-to NH_(3) Theoretical computations In situel ectrochemical measurements p-Block single-atom alloys

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia Xie Chengjia shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review

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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang shang-Xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

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氧等离子环境下影响多孔硅光学特性的因素

激光与红外 2011年第7期41卷 788-792页

作者：李平李清山张世玉马自侠鲁东大学物理学院山东烟台264025

研究了多孔硅(porous silicon,PS)在氧等离子体环境中退火温度和存储时间对PS光学稳定性的影响。通过光致发光(PL)谱和傅里叶变换红外光谱对系列样品进行分析。高斯拟合结果显示PL谱由三个高斯峰叠加而成,其中至少两个高斯峰是由非量子... 详细信息

研究了多孔硅(porous silicon,PS)在氧等离子体环境中退火温度和存储时间对PS光学稳定性的影响。通过光致发光(PL)谱和傅里叶变换红外光谱对系列样品进行分析。高斯拟合结果显示PL谱由三个高斯峰叠加而成,其中至少两个高斯峰是由非量子限制效应造成的,即第一峰面积的变化与Si=O双键密切相关,第三峰面积的变化与Si-O-Si桥键以及SiHx(x=1,2)键有关;退火温度对以上两个峰的强弱变化有直接影响。

关键词：多孔硅快速退火氧化非量子限制效应

Prospects of sea buckthorn(Hippophae rhamnoides L.)polysaccharides:preparation,structural characterization,and bioactivities diversity

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Food Science and Human Wellness 2025年第1期14卷 11-28页

作者： Shuyuan Shi Ruiyun Wu Zixin Han Yu Sun Pinglan li Fazheng Ren Nan shang Key Laboratory of Precision Nutrition and Food Quality College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Precision Nutrition and Food Quality Department of Nutrition and HealthyChina Agricultural UniversityBeijing 100083China

Sea buckthorn(Hippophae rhamnoides L.)is a natural homologous substance of medicine and ***,as one of its primary active components,has very superior biological activity and can be used as a dietary supplement for functional foods,with good commercial *** initial progress has been made in the study of sea buckthorn polysaccharides,related studies have been fragmented and lacked systematic and *** manuscript presents a critical analysis and systematic summary of the extraction and purification methods,structural characterization and physicochemical properties,biological activity and potential mechanisms,and structure-activity relationships of sea buckthorn *** evidence has indicated that sea buckthorn polysaccharides,which were widely prepared by water extraction and column chromatography purifications,exhibited exhibit superior biological activities in vitro and in vivo,including antioxidant,immunomodulatory,anti-inflammatory,hepatorenal protective,antibacterial,antiviral,and prebiotic *** analysis,it was concluded that there is a correlation between the relevant activities of sea buckthorn polysaccharides and that the structure of sea buckthorn polysaccharides has a great influence on their biological *** reviewed the challenges and limitations of sea buckthorn polysaccharides,summarized the critical aspects,and provided suggestions for potential breakthroughs in the research and application of sea buckthorn polysaccharide.

关键词： Sea buckthorn Polysaccharides Preparation Structural characterization Bioactivities

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单位球上F(p,q,s)空间的分解和刻画

数学学报（中文版） 2018年第6期61卷 1037-1048页

作者：肖建斌张学军尚清丽郭雨婷杭州电子科技大学杭州310037 湖南师范大学数学与统计学院长沙410006

设p〉0，s ≥ 0，q〉max{-n-1，-s-1}，本文探讨了单位球上F（p，q，s）空间的一种等价刻画和分解问题.具体结果为：（1） f∈ F（p，q，s）当且仅当f∈ H（B），且I^p=supa∈B∫B｜R^α，γf（z）｜^p（1-｜z｜2）q＋pγ-p（1-｜φa（... 详细信息

设p〉0，s ≥ 0，q〉max{-n-1，-s-1}，本文探讨了单位球上F（p，q，s）空间的一种等价刻画和分解问题.具体结果为：（1） f∈ F（p，q，s）当且仅当f∈ H（B），且I^p=supa∈B∫B｜R^α，γf（z）｜^p（1-｜z｜2）q＋pγ-p（1-｜φa（z）｜^2）^s dv（z）〈∞，其中α〉-1 和γ〉max{0，1-（q＋s＋1）/p，1-（q＋n＋1）/p}. （2）若{dk}∈ ∫p，则存在序列{wk}？B，使得 f（z）=∑k=1^∞（dk（1-｜wk｜2）t＋1）/（1-〈z，wk〉）t＋（q＋n＋1）/p）（z∈B）属于F（p，q，s），其中t〉max{1-1/p，0}（q＋n＋1）＋max{1/p，1}s-1.

关键词： F(p,q,s)空间等价刻画原子分解单位球

The Influence of Microbial Community on Oil Reservoirs:A Case Study on the Mesozoic Natural Gas in the Pengyang Area,Southwestern Ordos Basin,China

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Acta Geologica Sinica(English Edition) 2025年第1期99卷 144-158页

作者： shang Ting NIU Xiaobing li Mingrui ZHANG Zhongyi HUANG Xuan HAN Tianyou ZHANG Xiaolei li Jihong CHU Meijuan liU Xin School of Geography and the Environment Xianyang Normal UniversityXianyang712000China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an 710069China PetroChina Changqing Oilfield Company Xi'an 710018China Exploration&Development Research Institute of PetroChina Changqing Oilfield Company Xi'an 710018China National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields Xi'an 710018China Northwest University Xi’an 710069China

The formation of Mesozoic natural gas in the Pengyang area of southwestern Ordos Basin is discussed,from the perspective of microbial community characteristics,in order to clarify the relationship between the origin of natural gas and its associated indigenous microbial *** types and diversity of indigenous microbial communities associated with the oil reservoir were studied by means of collecting reservoir formation water samples from exploration *** indigenous microbial communities in the Chang 8 member of the Yanchang Formation were primarily distributed within Proteobacteria and Firmicutes,including the specific species and genera of Methylobacter,Pseudomonas,Haibacter,Toxobacillus,Acinetobacter and Adura *** results of diversity analysis shows that the number of common genes was 5448,while the number of unique genes and information was *** reflects the fact that the strata in the study area are relatively closed and not invaded by external water sources,which leads to the development of biological community *** conjunction with the analysis of geochemical characteristics of oil and gas reservoirs in this area,this indicates that the study area possesses the necessary geological conditions for microbial *** is the first time that the species and diversity of the indigenous microbial community in the Ordos Basin have been analyzed,showing that microbial degradation is the main cause of natural gas formation here,changes the characteristics of crude oil in this area and provides first-hand information on the impact of indigenous microorganisms on the reservoir.

关键词： microbial community source of natural gas Yanchang Formation Pengyang area Ordos Basin