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Evaluation of GOFP over four forest plots using RAmI and UAV measurements

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International journal of Digital Earth 2021年第10期14卷 1433-1451页

作者： jun Geng Qian Zhang Feng Qiu j.m.chen Yongguang Zhang Weiliang Fan Lili Tu jianwei Huang Shaoteng Wang Lichen Xu jinchao Li School of Civil Engineering Hefei University of TechnologyHefeiPeople’s Republic of China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei University of TechnologyHefeiPeople’s Republic of China jiangsu Provincial Key Laboratory of Geographic Information Science and Technology International Institute for Earth System ScienceNanjing UniversityNanjingPeople’s Republic of China max Planck Institute for Biogeochemistry JenaGermany Key Laboratory of Information Perception and Systems for Public Security of mIIT Nanjing University of Science and TechnologyNanjingChina Department of Geography and Program in Planning University of TorontoTorontoCanada School of Geographical Science Fujian Normal UniversityFuzhouPeople’s Republic of China College of Environmental and Resource Science Zhejiang A&F UniversityLinanPeople’s Republic of China School of Resources and Environment Anhui Agricultural UniversityHefeiPeople’s Republic of China

Comparison and validation of canopy reflectance(CR)models are two important steps to ensure their *** forest plantations are an ideal type of forest for validating CR models because of their simple background and the low variance in the crown structures which are usually assumed to be identical in most CR models.A Geometric Optical model for Forest Plantations(GOFP)was compared using dataset in two radiation transfer model intercomparison exercise(RAmI)stands and validated using in situ dataset of detailed optical and structural data of two forest plantations in the Saihanba Forestry Center,*** results show that(1)the tree distributions in stands described by the hypergeometric model in GOFP show good consistencies with the dataset in the two RAmI stands and measurements from the two Saihanba forest stands;and(2)the CRs simulated with GOFP are also compared well in the two RAmI stands and validated with measurements collected with unmanned aerial vehicles in the two Saihanba *** shows a better consistency with the CR measurements than those from CR models for natual forestsbecause the tree distribution in forest plantations is described more reasonably in GOFP.

关键词： Validation forest plantation GOFP tree distribution BRF hypergeometric model

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Al—Zn—mg三元合金的晶界偏析

轻合金加工技术 1979年第6期 50-58页

作者： j.m.chen 关学丰

使用俄歇电子光谱仪对合金添加剂在新淬火,未充分时效、峰值时效和过时效状态的三元Al—5.5％Zn—2.5％mg合金晶界处的含量分布情况进行了测量。AES深度分布图示出了mg和Zn在晶界处的明显偏析,它与以前对相同合金的测量结果完全不同。... 详细信息

使用俄歇电子光谱仪对合金添加剂在新淬火,未充分时效、峰值时效和过时效状态的三元Al—5.5％Zn—2.5％mg合金晶界处的含量分布情况进行了测量。AES深度分布图示出了mg和Zn在晶界处的明显偏析,它与以前对相同合金的测量结果完全不同。还发现,这种明显的矛盾,可通过AES光谱的等离子损失特点来阐明晶界偏析情况面得到解决。用AES等离子损耗测量方法,即可测定mg和Zn在晶界处的偏析,又能测定合金添加剂周围的冶金环境。还指出,过时效的Al合金试样,仅有部分mg(占晶界处总mg含量的一部分)进入了mgZn沉淀相,余者则集中分布在界面处的几个原子层内。

关键词：过时效晶界偏析 Zn mg 三元合金 Al

Sea salt aerosols as a reactive surface for inorganic and organic acidic gases in the arctic troposphere

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Sea salt aerosols as a reactive surface for inorganic and or...

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

第十二届全国气溶胶会议暨第十三届海峡两岸气溶胶技术研讨会

作者： j.W.Chi W.j.Li D.Z.Zhang j.C.Zhang Y.T.Lin X.j.Shen j.Y.Sun j.m.chen X. Y.Zhang Y.m.Zhang W.X.Wang Environment Research Institute Shandong University Faculty of Environmental and Symbiotic Sciences Prefectural University of Kumamoto Key Laboratory of the Earth' Deep Interior Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Atmospheric Chemistry of CmA Institute of Atmospheric CompositionChinese Academy of Meteorological Sciences

Sea salt aerosols(SSA) are dominant particles in the arctic atmosphere and determine the polar radiative balance. SSA react with acidic pollutants that lead to changes of physical and chemical properties of their surface, which in turn alter their hygroscopic and optical properties. Transmission electron microscopy with energy-dispersive X-ray spectrometry was used to analyze morphology, composition, size, and mixing state of individual SSA at Ny-?lesund, Svalbard in summertime. Individual fresh SSA contained cubic NaC l coated by certain amounts of mg Cl2 and Ca SO4. Individual partially aged SSA contained irregular NaC l coated by a mixture of NaN O3, Na2SO4, mg(NO3)2, and mgS O4. The comparison suggests the hydrophilic mg Cl2 coating in fresh SSA likely intrigued the heterogeneous reactions at the beginning of SSA and acidic gases. Individual fully aged SSA normally had Na2SO4 cores and an amorphous coating of NaN *** mappings of individual SSA particles revealed that as the particles ageing Cl gradually decreased but the C, N, O, and S content increased. 12C-mapping from nanoscale secondary ion mass spectrometry indicates that organic matter increased in the aged SSA compared with the fresh SSA. 12C- line scan further shows that organic matter was mainly concentrated on the aged SSA surface. These new findings indicate that this mixture of organic matter and Na NO3 on particle surfaces likely determines their hygroscopic and optical properties. These abundant SSA as reactive surfaces absorbing inorganic and organic acidic gases can shorten acidic gas lifetimes and influence the possible gaseous reactions in the arctic atmosphere, which need to be incorporated into atmospheric chemical models in the arctic troposphere.

关键词： Individual sea salt aerosols TEm heterogeneous reaction Arctic

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira m.Holmström Henri j.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing chen Huatian Shi Yue Wei Gui chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of molecular Functional materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NmP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m m Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI massimo CHIARADIA Chao WU Huayong chen Key Laboratory of mineralogy and metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of mineral Physics and materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（m）, which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： magma evolution V/Sc systematics magnetite Oxygen fugacity Porphyry copper deposits

Preparation of Low Ratio magnesium Ccement by Acid Leaching Treatment of Boron mud

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journal of Wuhan University of Technology(materials Science) 2025年第1期40卷 120-129页

作者： YANG mei ZHANG mingzhe chen Hao School of materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of mgO/mgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-mOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of mgO/mgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-mOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of mgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated m-S-H gel with mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-mOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

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Late Paleozoic–Early mesozoic tectonic evolution of the Zongwulong Shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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journal of Earth Science 2025年

作者： Yonghui Zhao chen Wu jie Li Peter j.Haproff Lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau experienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been extensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mixed crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental extension occurred in the northern margin of the Qaidam continent (ca. 416 ma–292 ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 ma–233 ma); and (3) subsequent late Triassic intracontinental extension (ca. 233 ma–215 ma). Our results suggest that the late Paleozoic–early mesozoic development of the Zongwulong Shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Hourglass-GCN for 3D Human Pose Estimation Using Skeleton Structure and View Correlation

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Computers, materials & Continua 2025年第1期82卷 173-191页

作者： Ange chen chengdong Wu Chuanjiang Leng Faculty of Robot Science and Engineering Northeastern UniversityShenyang110169China

Previous multi-view 3D human pose estimation methods neither correlate different human joints in each view nor model learnable correlations between the same joints in different views explicitly,meaning that skeleton structure information is not utilized and multi-view pose information is not completely ***,existing graph convolutional operations do not consider the specificity of different joints and different views of pose information when processing skeleton graphs,making the correlation weights between nodes in the graph and their neighborhood nodes *** Graph Convolutional Networks(GCNs)cannot extract global and deeplevel skeleton structure information and view correlations *** solve these problems,pre-estimated multiview 2D poses are designed as a multi-view skeleton graph to fuse skeleton priors and view correlations explicitly to process occlusion problem,with the skeleton-edge and symmetry-edge representing the structure correlations between adjacent joints in each viewof skeleton graph and the view-edge representing the view correlations between the same joints in different *** make graph convolution operation mine elaborate and sufficient skeleton structure information and view correlations,different correlation weights are assigned to different categories of neighborhood nodes and further assigned to each node in the *** on the graph convolution operation proposed above,a Residual Graph Convolution(RGC)module is designed as the basic module to be combined with the simplified Hourglass architecture to construct the Hourglass-GCN as our 3D pose estimation ***-GCNwith a symmetrical and concise architecture processes three scales ofmulti-viewskeleton graphs to extract local-to-global scale and shallow-to-deep level skeleton features *** results on common large 3D pose dataset Human3.6m and mPI-INF-3DHP show that Hourglass-GCN outperforms some excellent methods in 3D pose estimati

关键词： 3D human pose estimation multi-view skeleton graph elaborate graph convolution operation Hourglass-GCN