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Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests

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Chinese Geographical Science 2025年第1期35卷 55-72页

作者： YANG Rongjuan liu Ronggao liu Yang CHEN Jingming XU Mingzhu HE Jiaying State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350007China Department of Geography and Planning University of TorontoTorontoON M5S 3G3Canada

Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by *** present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical para-meter leaf area index(LAI),which are not completely synchronized in seasonality with *** this study,we proposed chlorophyll content-based light use efficiency model(CC-LUE)to improve GPP estimates,as chlorophyll is the direct site of photosynthesis,and only the light absorbed by chlorophyll is used in the photosynthetic *** CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy)and *** method was calibrated and validated utiliz-ing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five dif-ferent climate *** showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic *** CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season,outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model(VPM),and the eddy covariance-light use efficiency model(EC-LUE)).Additionally,the CC-LUE model(RMSE=0.50 g C/(m^(2)·d))significantly improved the underestimation of GPP during the growing season in semi-arid region,re-markably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%,73.4%,and 37.5%,compared with MOD17(RMSE=2.03 g C/(m^(2)·d)),VPM(RMSE=1.88 g C/(m^(2)·d)),and EC-LUE(RMSE=0.80 g C/(m^(2)·d))*** chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems,thereby provid-ing the possibility of a more precise depiction of forest seasonal carbon uptake.

关键词： canopy chlorophyll content(Chlcanopy) photosynthesis gross primary production(GPP) light use efficiency(LUE)model seasonal dynamics deciduous broadleaf forest(DBF)

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Construction of eco-friendly dual carbon dots ratiometric fluorescence probe for highly selective and efficient sensing mercury ion

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Journal of Environmental Sciences 2025年第2期148卷 1-12页

作者： Yongli liu Xiaoyan Su Huanjia liu Guifen Zhu Guobei Ge Yuxin Wang Penghui Zhou Qingxiang Zhou School of Environment Henan Key Laboratory for Environmental Pollution ControlKey Laboratory for Yellow River and Huai River Water Environmental and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China College of Chemical Engineering and Environment China University of Petroleum-BeijingBeijing 102249China

In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based on facile hydrothermal ***-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+utilizing b-CDs and *** developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 *** ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal,whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg^(2+)and r-CDs,serving as the reference signal in the sensing *** optimal circumstances,this probe exhibited an excellent linearity between the fluorescence response values of F450/F650 and Hg^(2+)concentrations over range of 0.01-10μmol/L,and the limit of detectionwas down to 5.3 nmol/***,this probe was successfully employed for sensing Hg^(2+)in practical environmental water samples with satisfied recoveries of 98.5%-105.0%.The constructed ratiometric fluorescent probe provided a rapid,environmental-friendly,reliable,and efficient platform for measuring trace Hg^(2+)in environmental field.

关键词： Blue carbon dots Red carbon dots Electron transfer Hg^(2+) Eco-friendliness

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New progresses of fine-grained sediment gravity-flow deposits and their importance for unconventional shale oil and gas plays

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Petroleum Science 2025年第1期22卷 1-15页

作者： Tian Yang Ying-Lin liu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology) Institute of Sedimentary Geology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of natural Resources Chengdu University of Technology

Fine-grained sediments are widely distributed and constitute the most abundant component in sedimentary systems, thus the research on their genesis and distribution is of great significance. In recent years, fine-grained sediment gravity-flows(FGSGF) have been recognized as an important transportation and depositional mechanism for accumulating thick successions of fine-grained sediments. Through a comprehensive review and synthesis of global research on FGSGF deposition, the characteristics,depositional mechanisms, and distribution patterns of fine-grained sediment gravity-flow deposits(FGSGFD) are discussed, and future research prospects are clarified. In addition to the traditionally recognized low-density turbidity current and muddy debris flow, wave-enhanced gravity flow, lowdensity muddy hyperpycnal flow, and hypopycnal plumes can all form widely distributed FGSGFD. At the same time, the evolution of FGSGF during transportation can result in transitional and hybrid gravityflow deposits. The combination of multiple triggering mechanisms promotes the widespread development of FGSGFD, without temporal and spatial limitations. Different types and concentrations of clay minerals, organic matters, and organo-clay complexes are the keys to controlling the flow transformation of FGSGF from low-concentration turbidity currents to high-concentration muddy debris flows. Further study is needed on the interaction mechanism of FGSGF caused by different initiations, the evolution of FGSGF with the effect of organic-inorganic synergy, and the controlling factors of the distribution patterns of FGSGFD. The study of FGSGFD can shed some new light on the formation of widely developed thin-bedded siltstones within shales. At the same time, these insights may broaden the exploration scope of shale oil and gas, which have important geological significances for unconventional shale oil and gas.

关键词： Fine-grained sediment gravity-flow Depositional mechanism Transportation and evolution Distribution pattern Shale oil and gas

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基于双伺服阀控非对称缸的液压缸系统压力跃变消除方法

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机电工程 2025年第2期42卷 307-314页

作者：张娜刘广治廊坊职业技术学院计算机科学与工程系河北廊坊065001 北京探矿工程研究所北京100083

压力跃变是阀控非对称缸系统固有的属性。液压缸活塞杆换向产生的压力跃变,使其不能对非对称缸系统进行精确控制,且使液压缸系统不能平稳工作。为此,提出了一种采用双伺服阀控非对称缸来消除压力跃变的方法,并对该方法进行了理论研究和... 详细信息

压力跃变是阀控非对称缸系统固有的属性。液压缸活塞杆换向产生的压力跃变,使其不能对非对称缸系统进行精确控制,且使液压缸系统不能平稳工作。为此,提出了一种采用双伺服阀控非对称缸来消除压力跃变的方法,并对该方法进行了理论研究和仿真分析。首先,在考虑容腔效应条件下,推导出了非对称缸两腔压力跃变幅值动态方程,确定了影响压力跃变幅值的因素;然后,推导出了双伺服阀控非对称液压缸压力跃变幅值动态方程,得到了采用双伺服阀控非对称液压缸来消除压力跃变时,两个伺服阀阀芯位移控制信号应满足的关系;在满足该关系的条件下,得到了不同性质载荷对非对称缸两腔压力跃变幅值的影响规律;最后,利用AMESim软件设计了双伺服阀控非对称液压缸系统的仿真模型,针对不同的可变负载进行了仿真分析,得到了非对称缸两腔压力的变化曲线。研究结果表明:对于恒定负载、线性变化负载和周期性变化负载,采用该方法可以有效消除非对称缸两腔压力跃变;对阶跃变化负载,采用该技术方案可以消除因流量不对称而导致的部分压力跃变。

关键词：非对称液压缸压力跃变容腔效应 AMESim 仿真分析压力跃变幅值动态方程压力变化曲线

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Three-step synthesis of flavanostilbenes with a 2-cyclohepten-1-one core by Cu-mediated [5+2] cycloaddition/decarboxylation cascade

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Chinese Chemical Letters 2025年第2期36卷 378-383页

作者： Gangsheng Li Xiang Yuan Fu liu zhihua liu Xujie Wang Yuanyuan liu Yanmin Chen Tingting Wang Yanan Yang Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical College Beijing Wehand-Bio Pharmaceutical Co. Ltd.

The first synthesis of flavanostilbenes with a 2-cyclohepten-1-one core was carried out by applying an effective strategy in three steps from abundant polymerized flavanol resources. A key regio-and stereoselective Cu-mediated [5+2] cycloaddition/decarboxylation cascade was explored and applied without the use of protecting groups, and water as an environmentally friendly solvent contributed to the cascade. The intramolecular [5+2] cycloaddition mechanism, involving oxidation and dearomatization of the flavanol unit as a diene, was proposed and supported by the synthesis of the intermediate. The regioselectivity of the cyclization was found to be dependent on the substitution effects of the stilbene units by the exploration of substrate scope.

关键词： Biomimetic synthesis Copper natural products Substrate [5 + 2] Cycloaddition

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Optimizing local search-based partial MaxSAT solving via initial assignment prediction

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Science China(Information Sciences) 2025年第2期68卷 59-73页

作者： Chanjuan liu Guangyuan liu Chuan LUO Shaowei CAI Zhendong LEI Wenjie ZHANG Yi CHU Guojing ZHANG School of Computer Science and Technology Dalian University of Technology School of Software Beihang University Institute of Software Chinese Academy of Sciences School of Computer Science Peking University

Partial maximum satisfiability(PMS) is a significant generalization of Boolean satisfiability(SAT) and maximum satisfiability(MaxSAT), by introducing hard clauses and soft clauses. Compared with SAT and MaxSAT, the PMS problem has more real-world applications where both hard and soft constraints are involved. Local search is an effective incomplete method for solving PMS and is useful for important domains where good-quality solutions are desired within reasonable *** local search PMS solvers, the approach for initial assignment generation is crucial because its effectiveness significantly affects practical performance. In this study, we propose a novel initial assignment prediction approach, called InitPMS. When predicting an assignment for PMS, InitPMS considers the specific structure of PMS instances, i.e., distinguishing hard and soft clauses. Our experiments on extensive PMS instances from MaxSAT evaluations(MSEs) 2020 and 2021 show that InitPMS significantly boosts the performance of five state-of-the-art local search PMS solvers, demonstrating its generality. In addition,our results indicate that incorporating InitPMS could improve the performance of one of the best incomplete PMS solvers in MaxSAT Evaluation 2021, indicating that InitPMS might help advance the state of the art in PMS solving.

关键词： MaxSAT local search initial assignment incomplete method assignment prediction

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High-resolution full waveform seismic imaging: Progresses, challenges, and prospects

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Science China Earth Sciences 2025年第2期68卷 315-342页

作者： Dinghui YANG Xingpeng DONG Jiandong HUANG zhilong FANG Xueyuan HUANG Shaolin liu Mengxue liu Weijuan MENG Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Institute of Geology China Earthquake AdministrationBeijing 100029China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China national Institute of natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China

Full waveform inversion(FWI) is a seismic imaging method with a unified mathematical framework based on wave equation constraints. The FWI method can be used to generate a variety of high-resolution seismic parameter models(e.g.,velocity, anisotropy, viscoelasticity, and attenuation), which can facilitate an in-depth understanding of important scientific problems such as the Earth's interior structure and material composition, earthquake preparation and occurrence, and plate motion and dynamic processes. With the development and cross-integration of disciplines such as geophysics, applied mathematics, and computer science, FWI imaging theories and methods not only play a crucial role in revealing the Earth's interior structure, dynamic evolution, and earthquake mechanisms but also show a wide range of application potential in fields such as resource exploration, medical imaging, engineering inspection, carbon dioxide geological sequestration, and earthquake disaster prediction. In this paper, we provide a comprehensive review and analysis of the development of the FWI method,addressing its current challenges, identifying key issues, future directions, and potential research areas in the theory, methodology, and application of high-resolution FWI imaging. We also offer new insights and perspectives to promote advancements of high-resolution FWI research and applications in Earth sciences and other related fields.

关键词： Full waveform inversion High-resolution imaging Interior structure of the Earth Earthquake preparation me-chanism Multidisciplinary integration

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Reduction of thermal stratification due to global warming in winter and spring

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Journal of Oceanology and Limnology 2025年第1期43卷 1-15页

作者： Jie liu Jianming DENG Xiangming TANG State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

Global warming has been reported to enhance thermal stratification and decrease the mixlayer depth(MLD)in waters due to higher surface water temperatures,especially in *** studies were conducted for individual cases or specific *** present,there is a lack of global assessments on the influence of climate warming in different seasons on thermal *** ECMWF Reanalysis v5(ERA5)dataset was used to estimate the variability of water body mixing and its drivers in different seasons and *** indicate that global warming could enhance thermal stratification and decrease the MLD globally in *** speed was the primary driver of MLD changes,followed by ***,ice melt due to global warming enhanced the mixing in icecovered waters in the Northern Hemisphere,and early ice melt led to early *** depth was the primary driver of MLD changes in the Northern Hemisphere due to delayed ice formation and earlier melting,while wind speed was the primary driver in other regions or during ice-free *** enhanced mixing due to earlier ice melt out in late winter and early spring could promote water circulation and nutrient turnover,and replenish dissolved oxygen in deep water,thereby promoting the maximum biomass of cyanobacteria and advance harmful algal blooms.

关键词： global warming mix-layer depth(MLD) thermal stratification ice depth ECMWF Reanalysis v5(ERA5)dataset

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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024 State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 nanosheets Scale-up synthesis Aromatic alkylation

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Unlocking the future:Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

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World Journal of Clinical Oncology 2025年第1期16卷 43-52页

作者： zhi-Jian Tang Yuan-Ming Pan Wei Li Rui-Qiong Ma Jian-liu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Cancer Research Center Beijing Chest HospitalBeijing 101149China Department of Thoracic Surgery Sichuan Provincial People's HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Mitochondrial genes are involved in tumor metabolism in ovarian cancer(OC)and affect immune cell infiltration and treatment *** To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural *** Prognosis,immunotherapy efficacy,and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression *** genes were sourced from the MitoCarta3.0 *** discovery cohort for model construction was created from 70% of the patients,whereas the remaining 30% constituted the validation *** the expression of mitochondrial genes as the predictor variable and based on neural network algorithm,the overall survival time and immunotherapy efficacy(complete or partial response)of patients were *** In total,375 patients with OC were included to construct the prognostic model,and 26 patients were included to construct the immune efficacy *** average area under the receiver operating characteristic curve of the prognostic model was 0.7268[95% confidence interval(CI):0.7258-0.7278]in the discovery cohort and 0.6475(95%CI:0.6466-0.6484)in the validation *** average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444(95%CI:0.8333-1.0000)in the discovery cohort and 0.9167(95%CI:0.6667-1.0000)in the validation *** The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC,providing valuable insights into personalized treatment strategies.

关键词： Ovarian cancer Mitochondria Prognosis Immunotherapy Neural network

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