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Spatially explicit changes of forestland in Taiwan Province from 1910 to 2010

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Journal of Geographical Sciences 2022年第3期32卷 441-457页

作者： YANG Xuhong JIN Xiaobin YANG Yongke song jiani ZHANG Tong ZHOU Yinkang School of Geography and Ocean Science Nanjing UniversityNanjing 210023China School of sciences Central South University of Forestry and TechnologyChangsha 410004China

Reconstructing long-term changes of forest cover(FC)can provide reliable underlying data for carbon source/sink accounting and simulation of the effects of land use on the climate and *** maps contain a wealth of forest related information and can provide first-hand data for studying the changes in FC over a long time *** the reconstruction of FC in Taiwan Province from 1910-2010 as the research object,we used map extraction and mining methods to extract forest distribution information from historical forest thematic survey maps,topographic and land cover maps,and reconstructed the spatiotemporal patterns of FC in Taiwan from *** results show that:first,the relative bias of the FC area extracted from the historical maps of Taiwan was below 8%,meaning the FC information contained in maps is highly ***,the FC of Taiwan has generally declined in the past 100 *** 1910-2010,the forest area declined from 2.62×10^(6) ha to 2.47×10^(6) ha,with relatively obvious forest reduction having *** stages,the forest area of Taiwan decreased by 26.39×10^(4) ha from 1910 to 1950;and increased by 10.53×10^(4) ha during the period *** reduction was obvious during the Japanese occupation period,while forest increase was remarkable during the Kuomintang ***,during the study period,the total area of patches maintained as forests was 2.17×10^(6) ha with little change in the overall pattern,and forests were mainly distributed in the mountain *** loss of forest mainly occurred in the plains,with expanding forest areas mainly in the mountain regions at high elevations and on steep ***,land clearing for agriculture during the Japanese occupation period has been the important driver of forest reduction in Taiwan over the past *** retreated to Taiwan,the Kuomintang government introduced effective and remarkable reforms that led to effective restoration of forest vegetation in many a

关键词： historical map forestland change spatiotemporal pattern driving force Taiwan

Diverse responses of fungal functional groups to desertification in forest soils of Pinus densata on the Chinese Tibetan plateau

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-11页

作者： Hua, jiani Zhang, Jiangbao song, Baohan Wang, Tianyi Li, Jingji Yang, Nan Mao, Lingfeng Nanjing Forestry Univ Coll Ecol & Environm Coinnovat Ctr Sustainable Forestry Southern China Lab Biodivers & Conservat Nanjing 210037 Peoples R China Chengdu Univ Technol Inst Ecol Resources & Landscape Architecture Chengdu 610059 Peoples R China

Rapid increase in desertification is an environmental concern, especially for the health and sustainability of ecosystems in changing climates. How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically important groups such as soil fungi functional groups. This study investigated variations in diversities of three soil fungi functional guilds (saprotrophic, symbiotic, pathogenic) and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense. The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi (mean relative abundance decreasing from 97.0% to 68.3%), in contrast to saprotrophic fungi (increasing from 2.7% to 25.7%) and pathogenic (from 0.3% to 5.9%). Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness, which was significantly lower in arid soils, and positively correlated with saprotrophic and pathogenic fungal alpha-diversity, which were abundant. Different community structures and regulators of the three fungi communities were observed, with pH, total phosphorus and ammonium (NH4+) as the main determinants. This study links the biotic and abiotic components during desertification and the interactions between them, and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a changing climate.

关键词： Desertification Fungal diversity Saprotrophs Ectomycorrhizal fungi Climate change MULTIPLE SEQUENCE ALIGNMENT MICROBIAL COMMUNITIES MYCORRHIZAL FUNGI PLANT DIVERSITY ENZYME-ACTIVITY ECTOMYCORRHIZAL PH ECOSYSTEM FRAMEWORK GRADIENT

基于组合赋权灰色关联法的木质板材火灾危险性研究

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西安科技大学学报 2024年第1期44卷 34-42页

作者：于志金宋佳妮徐澜李茜西安科技大学安全科学与工程学院陕西西安710054

为探究木质板材火灾危险性综合评价,选用6种常用木质板材(杉木板、松木板、榆木板、密度板、胶合板、刨花板),采用锥形量热仪与火蔓延试验平台测试6种板材的燃烧行为。将测得的燃烧反应特性参数分为燃烧特性、生烟特性、一般烟气毒性与... 详细信息

为探究木质板材火灾危险性综合评价,选用6种常用木质板材(杉木板、松木板、榆木板、密度板、胶合板、刨花板),采用锥形量热仪与火蔓延试验平台测试6种板材的燃烧行为。将测得的燃烧反应特性参数分为燃烧特性、生烟特性、一般烟气毒性与火焰蔓延特性4种指标因素,以构建木质板材火灾危险性综合评价指标体系,并提出一种基于博弈法组合赋权的改进灰色关联法,与火灾增长速率指数评价法进行对比,发现火灾增长速率指数评价法主要反映热释放速率快速增长阶段的热危险性,而改进灰色关联法在评价各指标因素上更全面。结果表明:组合赋权的改进灰色关联法能有效评价各指标因素对木质板材火灾危险性的影响,最终得到6种木质板材火灾危险性由小到大为:榆木板(0.674 8)>松木板(0.663 4)>刨花板(0.655 6)>杉木板(0.650 5)>密度板(0.637 7)>胶合板(0.633 0)。组合赋权的改进灰色关联法在评价材料火灾危险性时可以更科学、更全面地反映整个受火过程中的火灾危险性大小,是一种评价结果可信度高的思路。

关键词：熵权法 CRITIC法博弈论灰色关联度木质板材燃烧特性

CO_(2)激光-MAG电弧复合焊电弧能量对熔滴过渡特征和焊缝形貌的影响

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应用激光 2021年第1期41卷 154-160页

作者：刘凯宋佳妮吉林电子信息职业技术学院吉林吉林132021

以5.0 mm厚高强钢板为试验材料,采用CO_(2)激光-MAG电弧复合焊接方法,研究电弧电压与焊接电流的大小对复合焊接熔滴过渡特征、工艺稳定性和焊缝形貌的影响。结果表明,在激光功率P=1.6 kW、焊接速度v=1.2 m/min的情况下:当电弧电压U=26 ... 详细信息

以5.0 mm厚高强钢板为试验材料,采用CO_(2)激光-MAG电弧复合焊接方法,研究电弧电压与焊接电流的大小对复合焊接熔滴过渡特征、工艺稳定性和焊缝形貌的影响。结果表明,在激光功率P=1.6 kW、焊接速度v=1.2 m/min的情况下:当电弧电压U=26 V、焊接电流I<180 A时或焊接电流I=180 A、电弧电压U<24 V时,熔滴过渡模式为短路过渡和颗粒过渡或是二者的混合过渡,且焊缝表面飞溅较多;当电弧电压U≥24 V时或焊接电流I≥180 A时,熔滴的过渡模式为射滴过渡,且焊缝表面质量较好。

关键词：激光电弧复合焊接熔滴过渡熔滴过渡频率焊缝形状电弧能量

Clonal evolution analyses of a chronic myeloid leukemia patient with hematopoietic stem cell transplantation based on deep sequencing

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Holistic Integrative Oncology 2023年第1期2卷 85-92页

作者： Fuhua Yang Ping Wang Jia Wan Xiaoqing Jia An Zhou Yuan Zhang jiani song Qiang Gong Wei-Dong Li Jieping Chen Department of Genetics School of Basic Medical SciencesTianjin Medical UniversityTianjin 300070China Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin 300384China Department of Hematology Southwest HospitalArmy Medical UniversityChongqing 400038China

Background The Philadelphia(Ph)chromosome is the hallmark chromosome aberration in chronic myeloid leukemia(CML),which confers the cancer phenotype of the ***,how the Ph chromosome forms and the genetic clonal evolution structure after targeted Ph treatment are still *** In this study,we performed genome sequencing and clonal evolution analyses in a series of bone marrow specimens and skin biopsy from a CML patient who had received hematopoietic stem cell transplantation from her sister,then relapsed(lymphoid blast crisis),and received Ph-targeted *** The Ph chromosome was the“driver”clonal change in the original CML and the *** the patient and her sister had micro-deletions in the BCR gene region;however,the patient had a frameshift BRIP1 mutation that may account for the malfunctioning homologous recombination DNA repair of the BCR gene region and formation of the Ph *** We found that the BCR-ABL1 translocation was the driving force of the patient’s CML and *** malfunctioning double-strand DNA break repair caused by the BRIP1 mutation could be the cause of Ph chromosome formation in the patient.

关键词： Philadelphia chromosome Clonal evolution DNA repair Homologous recombination Targeted therapy

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

巧设情境营造自由言说空间——小学语文口语交际教学的有效策略探析

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当代家庭教育 2021年第31期 43-44页

作者：宋佳妮江苏省常州市新北区新桥第二实验小学

长期以来,小学语文教学活动中的一项重要内容即为口语交际,而言说能力作为学生所必备的一项语文能力,在教学活动中需要予以足够的重视。教师在教学活动中,需重视多种先进的教学方式、教学策略的引入,实现良好课堂教学氛围的构建,为学生... 详细信息

长期以来,小学语文教学活动中的一项重要内容即为口语交际,而言说能力作为学生所必备的一项语文能力,在教学活动中需要予以足够的重视。教师在教学活动中,需重视多种先进的教学方式、教学策略的引入,实现良好课堂教学氛围的构建,为学生充分地表达自我提供空间。笔者首先针对小学语文口语交际教学现状加以分析,其次针对小学语文口语交际教学的有效策略提出几点建议,望借此可以切实提高学生言说能力,推动学生语文素养发展。

关键词：言说能力小学语文口语交际教学

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano Research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature