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Tree Planting:How Fast Can It Accelerate Post-fire Forest Restoration?——A Case Study in Northern Da Hinggan Mountains,China

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Chinese Geographical Science 2010年第6期20卷 481-490页

作者： li Xiuzhen HE Hong S WANG Xugao XIE Fuju HU Yuanman li yuehui Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China School of Natural Resources University of Missouri-Columbia Columbia MO 65211- 72 70 USA

In 1987,a catastrophic fire burned over 1330000 ha in the densely forested area of the Da Hinggan Mountains in the northeastern *** the fire,intensive management including burned trunk harvesting and coniferous tree planting had been conducted to accelerate forest *** study the long term effect of these activities on forest recovery,we used a simulation modeling approach to study long-term(300 years) forest dynamics under current planting and natural regeneration *** indicate that under tree planting scenario in the severely burned area,the dominant species Dahurian larch(Larix gmelinii) can reach pre-fire level(60% of the area) within 20 years and the maximum abundance can reach nearly 90% within 100 *** under natural regeneration scenario,it needs about 250 years to reach its pre-fire *** the perspective of timber production,tree planting can bring twice as much timber volume as that under natural regeneration within 300 years,which is the average longevity of *** needs about 70 years to reach the timber volume of pre-fire level under the planting scenario,whereas it requires at least 250 years to reach the timber volume of pre-fire level under natural regeneration *** dominant species Asian White birch(Betula platyphylla) responded negatively to the planting of coniferous *** general,tree planting of coniferous species after fire can greatly accelerate forest restoration in terms of species abundance and target timber volume,with desirable ecological and economic returns.

关键词： tree planting natural regeneration post-fire forest restoration species abundance timber volume LANDIS model

Manipulation of surface phonon polaritons in Si C nanorods

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Science Bulletin 2020年第10期65卷 820-826,M0004页

作者： yuehui li Ruishi Qi Ruochen Shi Ning li Peng Gao International Center for Quantum Materials Peking UniversityBeijing 100871China Electron Microscopy Laboratory School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

Surface phonon polaritons(SPh Ps) are potentially very attractive for subwavelength control and manipulation of light at the infrared to terahertz wavelengths. Probing their propagation behavior in nanostructures is crucial to guide rational device design. Here, aided by monochromatic scanning transmission electron microscopy-electron energy loss spectroscopy technique, we measure the dispersion relation of SPh Ps in individual Si C nanorods and reveal the effects of size and shape. We find that the SPh Ps can be modulated by the geometric shape and size of Si C nanorods. The energy of SPh Ps shows redshift with decreasing radius and the surface optical phonon is mainly concentrated on the surface with large radius. Therefore, the fields can be precisely confined in specific positions by varying the size of the nanorod, allowing effective tuning at nanometer scale. The findings of this work are in agreement with dielectric response theory and numerical simulation, and provide novel strategies for manipulating light in polar dielectrics through shape and size control, enabling the design of novel nanoscale phononphotonic devices.

关键词： Surface phonon polariton Nanophotonics Nanostructure Geometry manipulation Phononic materials

Simulating Impact of Larch Caterpillar(Dendrolimus superans)on Fire Regime and Forest Landscape in Da Hinggan Mountains,Northeast China

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Chinese Geographical Science 2011年第5期21卷 575-586页

作者： CHEN Hongwei HU Yuanman CHANG Yu BU Rencang li yuehui liU Miao State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110164 China

Larch caterpillar (Dendrolimus superans) is very common in the Da Hinggan Mountains, Northeast China, affecting fire regime and forest ecosystem change at large spatio-temporal scales. In this study, we used a spatially explicit landscape model, LANDIS, to simulate the changes of fire regime and forest landscape under four larch caterpillar disturbance intensity levels scenarios in Huzhong forest area, northern of Da Hinggan Mountains. The results indicate that larch caterpillar disturbances would decrease fine fuel load and increase coarse fuel load in the 300 simulation years. Larch caterpillar disturbances would decrease fire frequency in the first 200 years, and the disturbances also decrease fire intensity and fire risk in the early and late stage of simulation. Larch caterpillar disturbances would decrease the area percent of larch cohorts and increase the proportion of white birch, and increase the degree of aggregation of white birch as a result of its strong seed dispersal and colonization ability. Disturbances would also decrease the mature and over-mature larch cohorts and increase all cohorts of white birch, especially the mature and over-mature cohorts. Larch caterpillar disturbances will decrease the stability of forest landscape, therefore,some measures preventing in- sect outbreak and ensuring the sustainable management of forest ecosystem should been taken in the study area.

关键词： forest landscape larch caterpillar fire disturbance LANDIS model

Recent developments in electrosynthesis of nitriles and electrocatalytic cyanations

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Journal of Energy Chemistry 2022年第7期31卷 542-575,I0014页

作者： Haiyan Hu Shanxuan Wu Fachao Yan Mohamed Makha Yuxia Sun Chen-Xia Du yuehui li State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICPCenter for Excellence in Molecular SynthesisLanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000GansuChina University of Chinese Academy of Sciences Zhengzhou 450001HenanChina College of Chemistry Zhengzhou UniversityBeijing 100049China

Nitrile compounds are a class of high-value chemicals and versatile intermediates which can easily be transformed into a variety of useful products bearing functional groups such as carboxyl, carbamoyl, aminomethyl, ketyl and heterocyclic derivatives. Various thermal catalytic cyanation procedures have been devised and scaled up industrially while developing alternative methods are actively pursued. The access to these classes of molecules electrochemically offers greener alternatives to their preparation. The development of electrochemical synthesis of cyano-containing compounds under mild conditions with low energy consumption will imminently become indispensable approaches for industrial production of nitriles. The electrochemical cyanation presents many challenges from the toxicity of cyanide to the development of catalysts and the design of electrochemical cells. Electrochemical cyanation reaction offers promise to conveniently accessing nitriles but still requires efficient electro-catalysts, safe protocols and scale up considerations. This review discusses recent progress in the field of electrochemical synthesis of nitrile compounds placing emphasis on electro-synthetic and electro-catalytic mechanism aspects while making reference to original works to highlight the progress in this area.

关键词： Cyano compounds Nitriles Cyanation Electrosynthesis Electrocatalysis

Effects of Forest Roads on Habitat Pattern for Sables in Da Hinggan Mountains, Northeasten China

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Chinese Geographical Science 2014年第5期24卷 587-598页

作者： li yuehui WU Wen XIONG Zaiping HU Yuanman CHANG Yu XIAO Duning State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences University of Chinese Academy of Sciences

The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road′s impact on animal habitats, we assessed the habitat pattern of sables(Martes zibellina), one of rodents within national first-class protected species, when roads are considered in Huzhong area in Da Hinggan Mountains, northeastern China. Employing published literatures about behavior ecology, aerial photographs and forest stand maps, we classified the study area into three habitat types including best-suitable, suitable and unsuitable habitats based on sable habitat requirements at the landscape scale including four variables derived from forest source map with attribute database. Results indicated the loss and significant fragmentation of best-suitable habitat and home range habitat when roads, especially 150 m avoidance distance of roads, were considered. The roads reduced and fragmented highly suitable habitats more significantly during earlier development period than the later development period. Additionally, the suitable area percentage increased with increasing distance to roads. This study helped to identify the suitable area for sables and location of sable population. Also, this study suggested the passage construction and road management involving road closure and removal will reduce the fragmentation functionally and benefit the sable population.

关键词： forest road sable habitat pattern buffer analysis Da Hinggan Mountains

Changes of forest fire regime and landscape pattern under different harvesting modes in a boreal forest of Northeast China

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Journal of Arid Land 2015年第6期7卷 841-851页

作者： CHEN Hongwei HU Yuanman CHANG Yu BU Rencang li yuehui liU Miao liaoning Key Laboratory of Urban Integrated Pest Management and Ecological Security Shenyang University State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences

Forest management such as timber harvesting shapes fire regimes and landscape patterns, and these patterns often differ significantly from those under natural disturbances. Our objective was to examine the effects of timber harvesting modes on fire regimes and landscape patterns in a boreal forest of Northeast China. We used a spatially explicit landscape model, LANDIS, to simulate the changes of forest landscape in the Huzhong forest region of the Great Khingan Mountains under no-cutting, clear-cutting, gradual-cutting and selective-cutting modes. Results showed that：（1） the fine fuel loadings generally decreased while the coarse fuel loadings increased with the increase of timber harvesting intensity;（2） the potential burn area significantly varied among different cutting modes, but the potential fire frequency had no obvious difference. Moreover, timber harvesting generally increased the potential fire risk;（3） clear-cutting mode significantly decreased the mean patch size and the aggregation of larch forests and increased the mean patch size and the aggregation of white birch forests. Therefore, clear-cutting mode should be abandoned, and selective-cutting mode be recommended for the sustainable forest management in the Great Khingan Mountains.

关键词： LANDIS clear-cutting gradual-cutting selective-cutting Great Khingan Mountains

LncRNA liNC01133在侵袭性牙周炎中的表达及作用

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解剖学杂志 2024年第3期47卷 225-230页

作者：田晓宇张雪白静任静李月辉遵化市人民医院唐山064200 唐山市丰润区人民医院口腔科唐山064000 开滦集团有限责任公司唐家庄医院口腔科唐山063100

目的:探讨lncRNA liNC01133在侵袭性牙周炎中的作用及机制。方法:用qRT-PCR检测不同正常人群及侵袭性牙周炎患者中不同炎症状态下牙龈组织中liNC01133、基质金属蛋白酶9(MMP-9)的表达,并用EliSA法检测其白细胞介素6(IL-6)、肿瘤坏死因子... 详细信息

目的:探讨lncRNA liNC01133在侵袭性牙周炎中的作用及机制。方法:用qRT-PCR检测不同正常人群及侵袭性牙周炎患者中不同炎症状态下牙龈组织中liNC01133、基质金属蛋白酶9(MMP-9)的表达,并用EliSA法检测其白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)炎症细胞因子。构建侵袭性牙周炎细胞模型,通过大肠杆菌脂多糖刺激人牙龈成纤维细胞(HGFs),体外培养检测HGFs细胞中liNC01133表达水平的变化。构建liNC01133过表达载体,转染HGFs,用qRT-PCR和免疫印迹检测载体相关mRNA及蛋白表达水平的变化。结果:侵袭性牙龈炎患者牙龈组织中liNC01133呈现低表达,MMP-9、IL-6、TNF-α呈现高表达,且liNC01133、MMP-9两者呈负相关。经过炎症细胞模型构建,HGFsliNC01133呈现低表达,且经过转染后上调liNC01133的表达,可以抑制MMP-9、IL-6、TNF-α的表达,从而减轻炎症的发生,改善侵袭性牙周炎的进展。结论:炎性牙龈组织中的liNC0113低表达,提示其参与侵袭性牙周炎的发病过程,且liNC01133可调控MMP-9、IL-6、TNF-α的表达,以调控侵袭性牙周炎的变化。

关键词：长链非编码RNA liNC01133 侵袭性牙周炎发病机制

Anthropogenic effect on forest landscape pattern and Cervidae habitats in northeastern China

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Journal of Geographical Sciences 2019年第7期29卷 1098-1112页

作者： WU Wen li yuehui HU Yuanman CHANG Yu XIONG Zaiping Jangho Architecture College Liaoning Provincial Key Laboratory of Urban and Architectural Digital Technology Northeastern University Shenyang 110819 China Key Laboratory of Forest Ecology and Management Institute of Applied Ecology CAS Shenyang 110016 China

Species abundance and habitat distribution are two important aspects of species conservation studies and both are affected by similar environmental factors. Forest resource inventory data in 2010 were used to evaluate the patterns of habitat for target species of Cervidae in six typical forestry bureaus of the Yichun forest area in the Lesser Xing’an Mountains, northeastern China. A habitat suitability index(HSI) model was used based on elevation, slope, aspect, vegetation and age of tree. These five environmental factors were selected by boosted regression tree(BRT) analysis from 14 environmental variables collected during field surveys. Changes in habitat caused by anthropogenic activities mainly involving settlement and road factors were also considered. The results identified 1780.49 km2 of most-suitable and 1770.70 km2 of unsuitable habitat areas under natural conditions, covering 16.38% and 16.29% of the entire study area, respectively. The area of most-suitable habitat had been reduced by 4.86% when human interference was taken into account, whereas the unsuitable habitat area had increased by 11.3%, indicating that anthropogenic disturbance turned some potential habitats into unsuitable ones. Landscape metrics indicated that average patch area declined while patch density and edge density increased. This suggests that as habitat becomes fragmented and its quality becomes degraded by human activities, cervid populations will be threatened with extirpation. The study helped identify the spatial extent of habitat influenced by anthropogenic interference for the local cervid population. As cervid species clearly avoid human activities, more attention should be paid on considering the way and intensity of human activities for habitat management as fully as possible.

关键词： Cervidae boosted regression tree habitat suitability assessment landscape pattern Lesser Xing'an Mountains

High-precision X-ray characterization for basic materials in modern high-end integrated circuit

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Journal of Semiconductors 2024年第7期45卷 12-24页

作者： Weiran Zhao Qiuqi Mo li Zheng Zhongliang li Xiaowei Zhang yuehui Yu National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China

Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic *** its early iterations to the advanced variants of today,this field has undergone an extraordinary *** the reliability requirements of integrated circuits continue to increase,the industry is placing greater emphasis on the crystal ***,conducting a range of characterization tests on the crystals has become *** paper will examine the correlation between crystal quality,device performance,and production yield,emphasizing the significance of crystal characterization tests and the important role of high-precision synchrotron radiation X-ray topography characterization in semiconductor ***,we will cover the specific applications of synchrotron radiation characterization in the development of semiconductor materials.

关键词： X-ray topography synchrotron radiation semiconductor materials crystal defects

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