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Development of monitoring and assessment of forest biomass and carbon storage in China

Forest Ecosystems 2015年第1期2卷 1-10页

作者： wei-sheng zeng Academy of Forest Inventory and Planning State Forestry Administration

Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese *** the development of monitoring and assessment of forest biomass and carbon storage in China is important for promoting the evaluation of forest carbon sequestration capacity of *** author conducts a systematic analysis of domestic publications addressing＂monitoring and assessment of forest biomass and carbon storage＂in order to understand the development trends,describes the brief history through three stages,and gives the situation of new *** the end of the 20th century,a large number of papers on biomass and productivity of the major forest types in China had been published,covering the exploration and efforts of more than 20 years,while investigations into assessment of forest carbon storage had barely *** on the data of the 7th and 8th National Forest Inventories,forest biomass and carbon storage of the entire country were assessed using individual tree biomass models and carbon conversion factors of major tree species,both previously published and newly *** the implementation of the 8th National Forest Inventory,a program of individual tree biomass modeling for major tree species in China was carried out *** means of thematic research on classification of modeling populations,as well as procedures for collecting samples and methodology for biomass modeling,two technical regulations on sample collection and model construction were published as ministerial standards for *** for approval of individual tree biomass models and carbon accounting parameters of major tree species have been issued for approval as ministerial *** the improvement of biomass models and carbon accounting parameters,thematic assessment of forest biomass and carbon storage will be gradually changed into a general monitoring of forest biomass and carbo

关键词： Biomass models Carbon accounting parameters Biomass conversion factor Root-to-shoot ratio Carbon storage

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Calorific values and ash contents of different parts of Masson pine trees in southern China

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Journal of Forestry Research 2014年第4期25卷 779-786页

作者： wei-sheng zeng Shou-zheng TANG Qian-hui XIAO Academy of Forest Inventory and Planning State Forestry Administration Research Institute of Forest Resources Information Techniques Chinese Academy of Forestry Central South Forest Inventory and Planning Institute State Forestry Administration

Calorific value of plants is an important parameter for evalu- ating and indexing material cycles and energy conversion in forest eco- systems. Based on mensuration data of 150 sample sets, we analyzed the calorific value （CV） and ash content （AC） of different parts of Masson pine （Pinus massoniana） trees in southern China using hypothesis testing and regression analysis. CV and AC of different tree parts were almost significantly different （P〈0.05）. In descending order, ash-free calorific value （AFCV） ranked as foliage 〉 branch 〉 stem bark 〉 root 〉 stem wood, and AC ranked as foliage 〉 stem bark 〉 root 〉 branch 〉 stem wood. CV and AC of stem wood from the top, middle and lower sections of trees differed significantly. CV increased from the top to the lower sections of the tnmk while AC decreased. Mean gross calorific value （GCV） and AFCV of aboveground parts were significantly higher than those of belowground parts （roots）. The mean GCV, AFCV and AC of a whole tree of Masson pine were 21.54 kJ/g, 21.74 kJ/g and 0.90%, re- spectively. CV and AC of different tree parts were, to some extent, cor- related with tree diameter, height and origin.

关键词： ash-free calorific value ash content gross calorific value hypothesis testing regression analysis Pinus massoniana

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The national forest inventory in China:history-results-international context

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Forest Ecosystems 2015年第4期2卷 288-303页

作者： wei sheng zeng Erkki Tomppo Sean P.Healey Klaus V.Gadow Academy of Forest Inventory and Planning State Forestry Administration Natural Resources Institute Finland Forest Service United States Department of Agriculture University of G?ttingen Beijing Forestry University Department of Forestry and Wood Technology University of Stellenbosch

Background： National forest resource assessments Inventories （NFI＇s）, constitute an important nationa and monitoring, commonly known as National Forest information infrastructure in many countries. Methods： This study presents details about developments of the NFI in China, including sampling and plot design and the uses of alternative data sources, and specifically · reviews the evolution of the national forest inventory in China through the 20th and 21st centuries, with some reference to Europe and the US; · highlights the emergence of some common international themes： consistency of measurement; sampling designs; implementation of improved technology; expansion of the variables monitored more efficient scientific transparency;· presents an example of how China＇s expanding NFI exemplifies these global trends. Results： Main results and important changes in China＇s NFI are documented, both to support continued trend analysis and to provide data users with historical perspective. Conclusions： New technologies and data needs ensure that the Chinese NFI, like the national inventories in other countries, will continue to evolve. Within the context of historical change and current conditions, likely directions for this evolution are suggested.

关键词： China Europe USA National forest inventories Forest inventory and analysis

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Construction of tree volume equations for Chinese fir plantations in Guizhou Province, southwestern China

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Forestry Studies in China 2013年第3期15卷 179-185页

作者： Zhong-sheng XIA wei-sheng zeng Song ZHU Hong-Zhang LUO Forest Resources Administration Office of Guizhou Province Institute of Forest Resources Information and Technology Chinese Academy of Forestry

Forest volume, the major component of forest biomass, is an important issue in forest resource *** is estimated from tree volume tables or equations. Based on tree volume data of 1840 sample trees from Chinese fir （Cunninghamia lanceolata） plantations in Guizhou Province in southwestern China, parallel one- and two-variable tree volume tables and tree height curves for central and other areas were constructed using an error-in-variable modeling method. The results show that, although the one-variable tree volume equations and height curves between the central and other areas were significantly different, the two-variable volume equations were sufficiently close, so that a generalized two-variable tree volume equation could be established for the entire province.

关键词： tree volume two-variable equation one-variable equation error-in-variable modeling method,parallel models Chinese fir

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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 791-805页

作者： Xu zeng Tao Yang Jian-wei Feng Cong-sheng Bian Ming Guan wei Liu Bing-Cheng Guo Jin Dong Research Institute of Petroleum Exploration and Development China National Petroleum CorporationBeijing100083China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China School of Earth Sciences China University of PetroleumQingdao266400ShandongChina

Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in th

关键词： Fractures Development characteristics Controlling factors Shale oil Sweet spot

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Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

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Journal of Iron and Steel Research International 2024年第6期31卷 1355-1366页

作者： sheng-hao Li Ao Huang Fan-bo zeng Hui Peng Hao-ran wei Xue-chun Huang sheng-qiang Song Hua-zhi Gu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory *** static magnetic field is a promising solution for improvement in the slag resistance of *** wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory *** slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy *** influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also *** contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory *** relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were *** provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

关键词： Alumina refractory ceramic Molten slag Weak magnetic field effect Reactive wetting Free radical

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An accurate and efficient space-time Galerkin spectral method for the subdiffusion equation

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Science China Mathematics 2024年第10期67卷 2387-2408页

作者： wei zeng Chuanju Xu School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High Performance Scientific Computing Xiamen UniversityXiamen 361005China

In this paper, we design and analyze a space-time spectral method for the subdiffusion ***, we are facing two difficulties. The first is that the solutions of this equation are usually singular near the initial time. Consequently, traditional high-order numerical methods in time are inefficient. The second obstacle is that the resulting system of the space-time spectral approach is usually large and time-consuming to solve. We aim at overcoming the first difficulty by proposing a novel approach in time, which is based on variable transformation techniques. Suitable ψ-fractional Sobolev spaces and a new variational framework are introduced to establish the well-posedness of the associated variational problem. This allows us to construct our space-time spectral method using a combination of temporal generalized Jacobi polynomials(GJPs) and spatial Legendre polynomials. For the second difficulty, we propose a fast algorithm to effectively solve the resulting linear system. The fast algorithm makes use of a matrix diagonalization in space and QZ decomposition in time. Our analysis and numerical experiments show that the proposed method is exponentially convergent with respect to the polynomial degrees in both space and time directions, even though the exact solution has very limited regularity.

关键词： subdiffusion equations variable transformation Ψ-Sobolev spaces well-posedness space-time Galerkin spectral method error estimate fast algorithm

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Source model of the 2018 M_(w)7.5 Papua New Guinea earthquake constrained by InSAR measurements: Insight into a blind rupture beneath the New Guinea Highlands

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Geodesy and Geodynamics 2024年第4期15卷 315-325页

作者： wei Chen Tianchen sheng wei Xiong Key Laboratory of Earthquake Geodesy Institute of SeismologyChina Earthquake AdministrationWuhan 430071China Qinghai Provincial Basic Surveying and Mapping Institute Xining 810001China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

The Southern Highland Fold and Thrust Belt(SHFTB),the boundary of the Australian plate and the New Guinea Highland block,significantly contributes to the convergent deformation along the plate ***,due to the lack of observation data,the detailed slip pattern of the SHFTB and the orogenic mechanism beneath the New Guinea Highlands remains *** 25 February 2018,the M_(w)7.5 Papua New Guinea(PNG)earthquake struck the southeastern segment of the *** detailed rupture characteristics of this event is significant for further clarifying the inter-seismic slip pattern along the ***,the coseismic deformation field of this earthquake was obtained using high-resolution ALOS-2 satellite *** find that the 2018 M_(w)7.5 PNG earthquake ruptured a large-scaled fault(SHFTB)extending to the lower crust(deeper than 20 km)beneath the New Guinea Highlands,with a dip angle of 24°.The slips on the fault plane are equivalent to moment magnitudes of M_(w)*** major asperities with thrust-dominated slip of up to 3.94 m are detected on the fault *** finding implies that the slip pattern on the eastern segment of the SHFTB is dominated by thrust,rather than with significant sinistral movement,as previously *** tectonic deformation across the New Guinea Highlands is possibly concentrated on the large-scale fault SHFTB and primarily controls the intra-continental orogeny in the central Papua New Guinea.

关键词： 2018M_(w)7.5PapuaNewGuineaearthquake The Southern Highlands Fold-and-Thrust Belt InSAR Slipdistribution Seismicrisk

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Theoretical study on the stability of nanobubbles and its verification in molecular dynamics simulation

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Particuology 2024年第4期87卷 99-105页

作者： sheng Mi Chaofeng Hou wei Ge School of Chemical Engineering and Technology Tianjin UniversityTianjin300072China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing.100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The stability of vapor nanobubbles in bulk liquid was investigated theoretically and the critical bubble size was derived from macroscale thermodynamic equations,below which the system destabilizes with sharp drop in *** critical size was quantitatively verified in molecular dynamic simulation using the Lennard-Jones model of argon,where stronger attraction between the molecules at lower density is found to contribute most to the drop of system pressure and,as the Laplace pressure on the curved bubble interface fails to balance the pressure difference across the interface,the bubbles become *** theoretical model could be extended to other systems where reliable equations of state and interfacial tension are available.

关键词： Nanobubble Stability Phase diagram Critical size

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Navigating Epstein–Barr virus autoimmunity:role of NK cells and T cells in multiple sclerosis

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Signal Transduction and Targeted Therapy 2024年第3期9卷 833-835页

作者： Chu Xie Cong Sun Mu-sheng zeng State Key Laboratory of Oncology in South China Guangdong Provincial Clinical Research Center for CancerGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapySun Yat-sen University Cancer CenterGuangzhouP.R.China

In a recent study published in Cell,Vietzen and colleagues discovered the novel role of natural killer(NK)cells and EBVspecific CD8+T cell response in controlling EBV-inducing autoimmune response and collectively def... 详细信息

关键词： Epstein sclerosis killer

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