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Mapping and Assessing Typhoon-induced Forest Disturbance in Changbai Mountain National Nature Reserve Using Time Series Landsat Imagery

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Journal of Mountain Science 2015年第2期12卷 404-416页

作者： GUO Xiao-yi ZhaNG Hong-yan WANG ye-qiao John Clark School of Geographical Sciences Northeast Normal University Department of Natural Resources Science University of Rhode Island

Monitoring forest disturbances is important for understanding changes in ecosystems. The 1986 Typhoon Vera was a serious disturbance that severely impacted the forest ecosystems of Changbai Mountain National Nature Reserve. Although the typhoon disturbance occurred more than two decades ago, the effects of the typhoon still remain within the study area. Few studies have focused on mapping and assessing disturbances across broad spatial and temporal scales. For this study, we first generated a map of forest composition prior to the typhoon disturbance, which served as a baseline data for the extraction of disturbed area. Then, the Disturbance Index(DI) method was tested for mapping the extent and magnitude of disturbance in the study area by applying a Tasseled Cap transformation to the Landsat imagery. The Landsatbased DI method estimated that an area of 13,764.78 ha of forest was disturbed by the typhoon. Based on visual assessments, these results correspond closely with the reference map derived from ground surveys. These results also revealed the influence of local topographic features on the distribution of windthrow areas. Windthrow areas were more pronounced inareas with elevations ranging from 1,000 to 2,000 m, slopes of less than 10 degrees, and southwestern to northwestern aspects. In addition, the relatively long(25 years) post-typhoon recovery period assessed by this study provided a more comprehensive analysis of the dynamics of forest recovery processes over time. Windthrow areas did not recover immediately after the typhoon, likely due to forest management practices enacted at the time. So far, forest recovery has proceeded more rapidly at elevations below 1,400 m, particularly on western slopes within the study area. Finally, a time series of DI values within the study period suggests a secondary disturbance may have occurred between 2000 and 2001.

关键词： Typhoon Vera Windthrow areas Disturbance Index(DI) Topographic features Forest recovery process

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Responses of soil nematode community to monoculture or mixed culture of a grass and a legume forage species in China

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Pedosphere 2020年第6期30卷 791-800页

作者： Yingying ye Yichao RUI Zhaoxia ZENG Xunyang HE Kelin WANG Jie ZhaO Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Huanjiang Observation and Research Station for Karst Ecosystems Chinese Academy of SciencesHuanjiang 547100China Department of Soil Science University of Wisconsin-MadisonMadison WI 53705USA University of Chinese Academy of Sciences Beijing 100049China

Mixed cultivation of fast-growing grasses and nitrogen(N)-fixing legumes for forage production is widely considered effective for obtaining sustained high forage yields without depleting soil N ***,the effects of monoculture and mixed culture of these species on soil food webs are poorly *** this study,soil nematode communities were examined as indicators of the soil food web structure of monoculture and mixed culture of grass and legume at three N levels,i.e.,338(low),450(moderate),and 675(high)kg N ha-1 year-1,across 2 years in wet and dry seasons,using the grass Paspalum wetsfeteini and the legume Medicago sativa(alfalfa),both commonly cultivated ***-measures analysis of covariance showed that compared with grass monoculture,legume monoculture and grass-legume mixture increased abundances of herbivorous,bacterivorous,and fungivorous nematodes in the soil food web under the low and moderate N fertilization *** response curve results showed that the abundance of Helicotylenchus,a plant parasite,was significantly higher under legume monoculture than other planting systems at the low N fertilization *** equation model analysis indicated that the legume increased bacterivore abundance,while increasing N fertilization decreased omnivore *** legume might increase the quantity and quality of food resources for soil biota,resulting in the bottom-up control of soil nematode *** results indicate that targeted control of a soilborne pathogen,Helicotylenchus,is required in alfalfa-based planting *** addition,high inorganic N application,which is detrimental to legume-rhizobia symbiosis,nullified the otherwise positive effects of legumes on soil nematodes.

关键词： bacterivore bottom-up control fertilization fungivore herbivore nitrogen soil food web soilborne pathogen

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How did the Tonga volcanic tsunami on January 15,2022,affect Chinese coasts?

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Science China Earth Sciences 2023年第5期66卷 1038-1046页

作者： Zongchen WANG Zhiguo XU ye YUAN Huaiwei YANG Lining SUN Peitao WANG Tingting FAN National Marine Environmental Forecasting Center Ministry of Natural Resources(National Tsunami Warning CenterMinistry of Natural Resources)Beijing100081China Key Laboratory of Marine hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing100081China

At 12:15 on January 15,2022(Beijing time),a massive eruption of the Hunga Tonga-Hunga ha'apai volcano produced violent atmospheric fluctuations,which in turn generated a global tsunami through an abrupt air pressure shock upon the sea *** main components of tsunami waves,phase-locked waves and free gravity waves,were identified by significant differences in propagating speeds across the deep *** phase-locked wave propagated through the ocean basin synchronously with the atmospheric Lamb wave at an average speed of approximately 306 m/s,followed by the free gravity wave at a slower *** locked wave reached the coast of eastern Taiwan Island at about 20:00 on January 15,in coincidence with the Lamb wave ***,on the coast of Chinese mainland,tidal gauges did not record tsunami signals until at least 2 h after the Lamb wave *** analyses and numerical experiments both suggested that as a result of the incoming wave shoaling above the vast continental shelf of Chinese mainland,the locked wave was no longer trapped by the air pressure shock and gradually transformed into freely-propagating shallow water waves by slowing down its *** to the longlasting planetary atmospheric fluctuations circling the earth many times,the sea level oscillations continuously propagated onto the Chinese shelf,which resulted in the tsunami waves excited along the Chinese coasts for at least 36 *** maximum wave amplitude recorded on the coast of eastern Taiwan Island was 44 cm at Wushi,while on the coasts of eastern and southern Chinese mainland,the maximum amplitudes were 22 cm at Shipu and 13 cm at *** and wavelet analyses were performed to identify the major components of the tsunami waves on the Chinese *** results indicated that eastern Taiwan Island was impacted mainly by the waves with periods of approximately 10-40 *** mainland was hit by the evolved shallow water waves and subsequent free waves,with pe

关键词： Volcanic tsunami Atmospheric Lamb wave Phase-locked-wave Free gravity wave Shallow water wave

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Crystal Structures of Two New Monoprotonated Products of 1,4,7 trimethyl-1,4,7-triazacyclononane: （Me3〔9〕aneN3H）(SO3CF3) and （Me3〔9〕aneN3H）I

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Chinese Journal of Structural Chemistry 2000年第1期19卷 48-52页

作者： DENG Dao Lia * ZhaNG Yan Hui a DAI Cong Yun a ZENG Hong a YAN Zhi Qing a ye Chang Qing a Ronald ha\|Ge ba (Unilever Research SIOC, 354 Fenglin Road, Shanghai 200032. China) b (Unilever Research Laboratorium, Olivier van Noor Unilever Research SIOC 上海 2 0 0 0 32 Unilever Research Laboratorium 荷兰 Vlaardinge

Two new monoprotonated products of macrocyclic polyamine 1,4,7 trimethyl 1,4,7 triazacyclononane(Me 3〔9〕aneN 3), (Me 3〔9〕aneN 3H)(SO 3CF 3) 1 (C 10 H 22 N 3O 3SF 3, M r =321.36) and (Me 3〔9〕aneN 3H)I 2 (C 9H 22 N 3I, M r =299.20) were obtained by the reactions of Me 3〔9〕aneN 3 and yttrium triflate or ytterbium diiodide as the unexpected products. The crystal structures of compounds 1 and 2 have been determined. Crystal 1 is orthorhombic, space group P2 12 12 1(#19), a =12.609(3), b=13.531(1), c=9.225(3) , V=1573.9(7)  3, Z=4, D c= 1.356 g/cm 3, μ =2.47 cm -1 , F (000)=680 and R=0.052, R w =0.052 for 807 unique reflections with I>2σ(I) . Crystal 2 belongs to the orthorhombic system with space group P2 12 12 1(#19), a=11.417(2), b=13.099(3), c=8.762(2) , V=1310.5(4)  3, Z=4, D c =1\^516 g/cm 3, μ =24.14 cm -1 , F (000)=600 and R=0.035, R w =0.042 for 1427 unique reflections with I>3σ(I) . The two structures contain the same cyclic framework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away from the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles for 1 and 2 also exhibit obvious diversity inside of triazacyclononae.

关键词： formation crystal structure protonation triazacyclononane

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Synthesis of waterborne polyurethane-humic acid cross-linked biomass porous materials for the adsorption of methylene blue

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Chinese Journal of Chemical Engineering 2024年第3期67卷 27-38页

作者： Shanghong Ma Jianbo Qu haitao Zhang Xiubin Cui Peng ye Qingfei Hu Mingzhen Chao State Key Laboratory of Biobased Material and Green Papermaking Qilu University of TechnologyShandong Academy of SciencesJinan 250353China Faculty of Light Industry Qilu University of TechnologyShandong Academy of SciencesJinan 250353China

A series of adsorbent materials(WPU-hax-y)with a three-dimensional porous structure,green sustainability,and excellent performance were prepared and evaluated for the removal of methylene blue using nontoxic and environmentally friendly waterborne polyurethane as the matrix material and humic acid,a biomass material,as the functional *** newly synthesized adsorbents were characterized by infrared spectroscopy,scanning electron microscopy,specific surface area,and *** effects of contact time(0-8 h),starting concentration(10-100 mg·L^(-1)),pH(3-11),solution temperature(30-60℃),and coexisting ions(Ca2+,Na+,K+,Mg2+)on the performance were ***-first-order,pseudo-second-order,elovich,and intra-particle diffusion models were used to analyze the adsorption kinetics;the Langmuir,Freundlich,Temkin,and Dubin-Radushkovich adsorption isotherms were evaluated;and the adsorption behavior of the adsorbent materials was found to be more appropriate for the pseudo-second-order model for chemical pollutant removal than the Langmuir model,which depends on monolayer ***-ha2-3 stood out with a maximum adsorption capacity of 813.0081 mg·g^(-1) fitted to the pseudo-second-order and 309.2832 mg·g^(-1) fitted to the Langmuir model,showing superior adsorption performance and regenerability.

关键词： Porous media Bioenergy Sustainability Waste water

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Carbon storage dynamics of subtropical forests estimated with multi-period forest inventories at a regional scale:the case of Jiangxi forests

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Journal of Forestry Research 2020年第4期31卷 1247-1254页

作者： Qiugen Zhang hao ye Yuan Ding Qun Cao Yangjian Zhang Ke Huang School of Environment and Chemistry Engineering Nanchang HangKong UniversityNanchang 330063People’s Republic of China Institute of Geographical Sciences and Natural Resources Research Beijing 100101People’s Republic of China

Temperate and high-latitude forests are carbon sinks and play pivotal roles in offsetting greenhouse gas emissions of ***,uncertainty still exists for subtropical forests,especially in monsoon-prevalent eastern *** studies have depended on remote sensing,ecosystem modeling,carbon fluxes,or single period forest surveys to estimate carbon sequestration capacities,and the results vary *** study was designed to utilize multi-period forest survey data to explore spatial-dynamics of biomass storage in subtropical forests of *** province,a region with over 60%subtropical forest cover,was selected as the case study site and is located in central east *** on forest inventory data 1984-2013,and the stock-difference and biomass expansion factor methods,the carbon storage and density,of arboreal forests,economic forests,bamboo forests,woodlands and shrubberies were *** results show that carbon storage increased from 159.1 Tg C in 1988 to 276.1 TgC in 2013,making up 3.1-3.8%of carbon stored throughout *** the four types of forests,the amount of carbon stored was as follows:arboreal forest>economic forest>bamboo forest>woodland and *** forests accounted for 64.0-79.4%of the *** carbon density increased from 21.2 Mg C ha-1 in 1984 to26.2 Mg C ha-1 in 2013,equal to 61.2-70.2%of the average carbon density of China’s forests in the same *** carbon storage in Jiangxi will reach 355.5 Tg C and 535.8 Tg C in 2020 and 2030,respectively,and forest carbon density is predicted to be 31.9 Mg C ha-1and 46.4 Mg C ha-1,*** one of the few studies using multi-period data tracking biomass dynamics in Jiangxi province,the findings of this study may be used as a reference for other *** Jiangxi as a case study underlies the fact that subtropical forests in China have great carbon sequestration potential and have fundamental significance to offset global environmental change eff

关键词： Subtropical forests Carbon storage/carbon density Multi-period inventories Prediction Jiangxi Province

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庆大霉素对羟基磷灰石/壳聚糖复合材料性能的影响

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无机化学学报 2010年第1期26卷 106-111页

作者：赵宏霞金花蔡继业暨南大学生命科学院广州510632 广东工业大学轻工化工学院广州510090

羟基磷灰石/壳聚糖-庆大霉素(ha/CS-G)缓释材料为骨髓炎的定点缓释给药提供了一种有效的局部药物缓释体系。为了研究抗生素对羟基磷灰石/壳聚糖材料性能的影响,采用共沉淀法制备了ha/CS-G缓释材料。利用红外光谱(IR)、X射线衍射(XRD)和... 详细信息

羟基磷灰石/壳聚糖-庆大霉素(ha/CS-G)缓释材料为骨髓炎的定点缓释给药提供了一种有效的局部药物缓释体系。为了研究抗生素对羟基磷灰石/壳聚糖材料性能的影响,采用共沉淀法制备了ha/CS-G缓释材料。利用红外光谱(IR)、X射线衍射(XRD)和扫描电子显微镜(SEM)对材料进行了表征。以不载药的羟基磷灰石/壳聚糖(ha/CS)为对照,研究了庆大霉素对ha/CS复合材料抑菌性能、力学性能和降解性能等的影响。实验结果表明,ha/CS-G有良好的抑菌效果。负载庆大霉素后ha/CS的机械强度明显增强,而材料的降解速率有所下降。本文采用的二次成型技术显著增大了材料的机械强度。

关键词：壳聚糖羟基磷灰石庆大霉素局部药物缓释体系

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STUDIES OK TRANSFORMATION FOR ZEOLITE CRYSTAL(Ⅲ)——THE STABILITY OF ZEOLITE NaY AND THE STRUCTURE OF ZEOLITE NaPc

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Chemical Journal of Chinese Universities 1985年第2期 16-22页

作者： ha Shujie,Li Liansheng,Xu Ruren and ye Chaohui (Chemistry Dept.,Jilin University,Changchun) (Wuhan Institute of Physics,Wuhan)

We investigated the crystallization of NaY and especially the transformation for NaY to NaPc type zeolite from an initial gel of the batch composition 3.3Na2O Al2O3 10SiO2 200H2O at 100℃and the changes of zeolite structures in the process of the transformation crystal using the modern techniques,A more detailed liquid phase transportation mechanism of the transformation was suggested.

关键词： NaY Th THE STABILITY OF ZEOLITE NaY AND THE STRUCTURE OF ZEOLITE NaPc STUDIES OK TRANSFORMATION FOR ZEOLITE CRYSTAL OK

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中国音乐治疗文献的统计分析

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毕节学院学报（综合版） 2015年第5期33卷 72-78页

作者：庾晓萌金野 KIM ha-kyung 昆明学院教师教育学院云南昆明650220 华东师范大学言语听觉科学教育部重点实验室上海200062 华东师范大学言语听觉康复科学系上海200062

音乐治疗作为康复领域的新兴疗法,正日益成为当前研究的热点。近年来,中国音乐治疗研究文献数量正不断上升,越来越多的研究者把关注点放在了临床运用领域,然而随着音乐治疗临床应用的不断展开,很多细节却暴露了中国音乐治疗发展中存在... 详细信息

音乐治疗作为康复领域的新兴疗法,正日益成为当前研究的热点。近年来,中国音乐治疗研究文献数量正不断上升,越来越多的研究者把关注点放在了临床运用领域,然而随着音乐治疗临床应用的不断展开,很多细节却暴露了中国音乐治疗发展中存在的不足。综述了中国音乐治疗研究论文概况,采用文献计量学方法,以频次和百分比为主要统计方式从各种指标入手定量分析中国音乐治疗研究文献,并就目前中国音乐治疗中存在的问题进行讨论。

关键词：音乐治疗定量分析中国音乐治疗文献

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多模式机械补偿运行特性研究

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原子能科学技术 2016年第4期50卷 684-690页

作者：叶青杨波党哈雷施建锋上海核工程研究设计院上海200233

经济、灵活及高自动化的运行控制策略是先进核电厂的设计目标之一。为适应这一发展趋势,近年来国际上提出了机械补偿运行控制的设计理念。机械补偿是一种主要通过控制棒的移动补偿堆芯反应性变化和控制轴向功率分布的先进控制策略。本... 详细信息

经济、灵活及高自动化的运行控制策略是先进核电厂的设计目标之一。为适应这一发展趋势,近年来国际上提出了机械补偿运行控制的设计理念。机械补偿是一种主要通过控制棒的移动补偿堆芯反应性变化和控制轴向功率分布的先进控制策略。本文分别在基本负荷、负荷跟踪及启动/再启动运行模式下对机械补偿运行特性进行了研究。研究表明:机械补偿能自动实现堆芯的有效控制,并使功率峰因子保持在较低水平,是一种灵活、有效、经济的运行控制策略。此外,针对机械补偿运行对核电厂设计的影响进行了初步分析。

关键词：机械补偿基本负荷负荷跟踪启动运行

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