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^137Cs tracing dynamics of soil erosion,organic carbon,and total nitrogen in terraced fields and forestland in the Middle Mountains of Nepal

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Journal of Mountain Science 2016年第10期13卷 1829-1839页

作者： SU Zheng-an XIONG dong-hong DENG Wei dong yi-fan MA Jing PADMA C Poudel GURUNG B Sher Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Belting 100049China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYa'an 625014China Central Department of Geography University CampusTribhuvan UniversityKirtipur 8212Nepal

The Middle Mountains is one of the regions of Nepal most vulnerable to water erosion, where fragile geology, steep topography, anomalous climatic conditions, and intensive human activity have resulted in serious soil erosion and enhanced land degradation. Based on the 137 Cs tracing method, spatial variations in soil erosion, organic carbon, and total nitrogen(TN) in terraced fields lacking field banks and forestland were determined. Soil samples were collected at approximately 5 m and 20 m intervals along terraced field series and forestland transects respectively. Mean 137 Cs inventories of the four soil cores from the reference site was estimated at 574.33 ± 126.22 Bq m-2(1 Bq(i.e., one Becquerel) is equal to 1 disintegration per second(1 dps)). For each terrace, the 137 Cs inventory generally increased fromupper to lower slope positions, accompanied by a decrease in the soil erosion rate. Along the entire terraced toposequence, 137 Cs data showed that abrupt changes in soil erosion rates could occur between the lower part of the upper terrace and the upper part of the immediate terrace within a small distance. This result indicated that tillage erosion is also a dominant erosion type in the sloping farmland of this area. At the same time, we observed a fluctuant decrease in soil erosion rates for the whole terraced toposequence as well as a net deposition at the toe terrace. Although steep terraces(lacking banks and hedgerows) to some extent could act to limit soil sediment accumulation in catchments, soil erosion in the terraced field was determined to be serious. For forestland, with the exception of serious soil erosion that had taken place at the top of slopes due to concentrated flows from a country road situated above the forestland site, spatialvariation in soil erosion was similar to the "standard" water erosion model. Soil organic carbon(SOC) and TN inventories showed similar spatial patterns to the 137 Cs inventory for both toposequences investigated.

关键词： Nepal 137Cs inventory Soil erosion/deposition Soil organic carbon Total nitrogen

The sediment delivery ratio in a small catchment in the black soil region of Northeast China

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International Journal of Sediment Research 2013年第1期28卷 111-117页

作者： yi-fan dong Yong-qiu WU Tian-yu ZHANG Wei YANG Bao-yuan LIU State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University MOE Engineering Center of Desertification and Blown-Sand Control Beijing Normal University Key Laboratory of Mountain Hazards & Surface Process Chinese Academy of Sciences School of Geography Beijing Normal University

The black soil region of northeast China,which covers the Provinces of Heilongjiang,Jilin and the Inner Mongolia autonomous region with black soil,chernozem and meadow soil,has experienced soil erosion since intense agricultural reclamation began approximately 100 years ***,the sediment delivery ratio,defined as the fraction of gross erosion that is transported from a given area in a given time interval,is still *** this study,we calculated the delivery ratio and analysed changes in erosive processes within Hebei catchment from 1977 to 2007 based on an analysis of sediments of the Liudui *** original vegetation layer clearly identified the bottom of the reservoir when it was constructed in 1977;thus,the reservoir sediments could be precisely *** delivery ratio,calculated by comparing the sediment deposition in the reservoir with the total soil erosion in the upstream catchment,was found to be exponentially correlated（r;= 0.95,P < 0.01） with decreasing grain size,except for the fraction <0.002 *** delivery ratio for the clays（<0.002 mm） was low,averaging 0.10 during the study period, which indicated partial removal of clays from the *** changes in the reservoir deposition rate reflected the temporal changes in the erosion *** exceptionally high rainfall in 1998 was confirmed by the distributions of;Cs,;Pb,and the grain-size of the *** from the position of the original grass layer,we defined three periods from 1977 to 2007 based on deposition rates:2.40 cm year;from 1977 to 1997,5.60 cm year;in 1998 due to unusually high rainfall,and 1.55 cm year;from 1999 to *** overall average deposition rate for the entire period was 2.26 cm year;.Precipitation was found to be the main factor affecting the soil erosion of the study area.

关键词： Sediment delivery ratio Reservoir sediments Black soils China

Radiation combined high doses IA chemotherapy against advanced head and neck malignant tumor

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中国口腔颌面外科杂志 2008年第B5期6卷 158-159页

作者： Cai yi Li Xin dong fan Lin Zhang Department of Oral and Maxillofacial Surgery Ninth People's Hospital Shanghai Jiao Tong University Shanghai 200011 China

考虑叶片停机位置大型风力机塔架风-沙致结构响应分析

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振动工程学报 2021年第1期34卷 60-71页

作者：柯世堂董依帆南京航空航天大学土木工程系江苏南京210016

强风停机状态下叶片位置会显著影响风力机塔架的绕流及稳定性能,尤其在沙尘暴极端天气条件下,沙粒的附着也会影响风的湍流特征并对塔架产生附加冲击力,现有工作均缺乏风-沙耦合作用对大型风力机体系气动性能及结构响应的探索。以南京航... 详细信息

强风停机状态下叶片位置会显著影响风力机塔架的绕流及稳定性能,尤其在沙尘暴极端天气条件下,沙粒的附着也会影响风的湍流特征并对塔架产生附加冲击力,现有工作均缺乏风-沙耦合作用对大型风力机体系气动性能及结构响应的探索。以南京航空航天大学自主研发的5 MW水平轴风力机体系为对象,以风-沙双向耦合算法为核心,基于CFD技术分别采用连续相和离散相模型进行典型风场和沙粒组合的同步迭代模拟。考虑叶片单个旋转周期内8个停机位置,对比分析了风力机塔架表面等效压力系数和气动载荷分布特性;结合有限元方法系统探讨了不同停机位置下风力机体系动力特性、风-沙致结构响应和屈曲稳定性能。研究表明:风-沙耦合环境下沙粒在风力机塔架迎风面底部产生的荷载效应最为显著,部分区域沙致压力系数可达0.55,沙粒冲击荷载与风荷载的比值最高可达23.7%;不同停机位下风荷载均对塔架结构响应起主导作用,但沙粒冲击作用在塔架底部的放大效应不可忽视。

关键词：大型风力机体系风-沙耦合环境结构响应 CFD数值模拟停机位置

Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit

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Energy Engineering 2025年第1期122卷 167-184页

作者： Yun Zhang ZifenHan Biao Tian Ning Chen yi fan School of Mechano-Electronic Engineering Xidian UniversityXi’an710071China Electric Power Control Center State Grid Gansu Electric Power CompanyLanzhou730030China Electric Power Control Center State Grid Gansu Electric Power Company Zhangye Power Supply BranchZhangye734000China

The new energy power generation is becoming increasingly important in the power *** as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power *** solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage ***,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage ***,the fuzzy control algorithm is introduced to balance the power between energy *** this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current *** is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units.

关键词： Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control

Effects of probiotics and prebiotics on intestinal microbiota in mice with acute colitis based on 16S rRNA gene sequencing

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Chinese Medical Journal 2019年第15期132卷 1833-1842页

作者： Ya-Nan Wang Xiang-Chen Meng yi-fan dong Xin-Hua Zhao Jia-Ming Qian Hong-ying Wang Jing-Nan Li Department of Gastroenterology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China National Cancer Center/Cancer Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100021 China

Background:Imbalance of intestinal microbiota was closely related to *** these circumstances,regulation of enteric flora may be beneficial to the repair of *** aimed to investigate the effects of probiotics (Bifidobacterium and Lactobacillus),prebiotics and their combination on inflammation,and microflora in mice of acute ***:C57BL/6J mice were divided into six groups randomly (blank control group,model control group,probiotics group,synbiotics group,lactitol group and probiotics + lactitol group).Each group was given 2.5% dextran sulfate sodium drinking water for 5 days other than the blank control *** for the model control group,the other four groups were intervened with probiotics,synbiotics (probiotics and inulin),lactitol,and probiotics + *** were sacrificed after 1 week of gavage,and pathologic scores were *** feces of different periods and intestinal mucosa samples were collected to analyze the differences of intestinal microbiota by 16S rRNA *** of two groups or multiple groups were statistically examined through unpaired Student t test and analysis of variance (ANOVA),***,Tukey,Anosim,and metastats analysis were used to compare differences of microbiota among different ***:After gavage for 1 week,the pathologic scores of groups with the intervention were significantly lower than those in the model control group,and the difference was statistically significant (P < 0.05).The model control group was higher in the genus of Bacteroides (relative abundance:0.3679 vs.0.0099,P =0.0016) and lower in Lactobacillus (relative abundance:0.0020 vs.0.0122,P =0.0188),Roseburia (relative abundance:0.0004 vs.0.0109,P =0.0157),compared with the blank control ***,the same phenomenon was not found in groups gavaged with probiotics and *** with model control group,mice with intervention were increased with Bifidobacterium (relative abundance:0.017

关键词： Probiotics Lactitol Intestinal microbiota Akkermansia

对近两年图书馆界关于“浅阅读”问题研究的述评

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图书馆论坛 2009年第3期29卷 11-13,27页

作者：董一凡福建师范大学社会历史学院福建福州350007

"浅阅读"方式的研究,是近两年"图书馆与社会阅读"论题关注的焦点之一,图书馆界对"浅阅读"基本上是持否定态度。笔者认为,"浅阅读"不是所谓的"勿需思考"、"浅显浏览"的阅读方式和阅读习惯,也不存在所谓的"危害严重"的社会问题,它是当代... 详细信息

"浅阅读"方式的研究,是近两年"图书馆与社会阅读"论题关注的焦点之一,图书馆界对"浅阅读"基本上是持否定态度。笔者认为,"浅阅读"不是所谓的"勿需思考"、"浅显浏览"的阅读方式和阅读习惯,也不存在所谓的"危害严重"的社会问题,它是当代读者积极应对海量信息的一种阅读方法。为此,图书馆应贯彻落实《图书馆服务宣言》精神,实施人性化、个性化的有效服务,为读者自由方便地利用文献创造条件。

关键词：图书馆界浅阅读研究述评

Salen Mn(Ⅱ)、Eu(Ⅲ)配合物抗O_2^(·-)活性及其与DNA作用的光谱性质研究

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光谱学与光谱分析 2010年第5期30卷 1386-1390页

作者：周花蕾董逸帆杨运旭邓小容鲁毅强北京科技大学化学系北京100083 河南省实验中学河南郑州450002

合成了5种Salen Mn(Ⅱ)及2种Salen Eu(Ⅲ)配合物。以NBT/核黄素(VB2)/蛋氨酸为O2.-的产生、检测体系,对上述配合物进行了抗O2.-活性研究,发现Mn(Ⅱ)配合物对O2.-均具有较为明显的清除活性。用荧光检测法对上述配合物与ct-DNA的作用进行... 详细信息

合成了5种Salen Mn(Ⅱ)及2种Salen Eu(Ⅲ)配合物。以NBT/核黄素(VB2)/蛋氨酸为O2.-的产生、检测体系,对上述配合物进行了抗O2.-活性研究,发现Mn(Ⅱ)配合物对O2.-均具有较为明显的清除活性。用荧光检测法对上述配合物与ct-DNA的作用进行了研究,结果显示其均能与DNA产生结合作用,提示具有潜在抗癌活性。

关键词： Salen Mn(Ⅱ) Salen Eu(Ⅲ) O2·- DNA 光谱

Microglia lactylation in relation to central nervous system diseases

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Neural Regeneration Research 2025年第1期20卷 29-40页

作者： Hui Yang Nan Mo Le Tong Jianhong dong Ziwei fan Mengxian Jia Juanqing Yue ying Wang School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Clinical Laboratory The Fourth Clinical Medical College of Zhejiang University of Traditional Chinese Medicine(Hangzhou First People’s Hospital)HangzhouZhejiang ProvinceChina College of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina

The development of neurodegenerative diseases is closely related to the disruption of central nervous system ***,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative *** has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of *** is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various *** review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting ***,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

关键词： brain central nervous system glycolysis immune response inflammation lactate metabolism lactate lactylation microglia neurodegenerative diseases