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Current re-vegetation patterns and restoration issues in degraded geological phosphorus-rich mountain areas:A synthetic analysis of Central Yunnan, SW China

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Plant Diversity 2017年第3期39卷 140-148页

作者： Kai Yan Sailesh Ranjitkar Deli Zhai yunju li Jianchu Xu Bo li Yang Lu Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences World Agroforestry Center ICRAF East and Central Asia The State Phosphorus Resource Development and Utilization Engineering Technology Research Centre Yunnan Phosphate Chemical Group Co. Ltd College of Resource and Environment Yunnan Agricultural University

China has the largest area of inland geological phosphorus-rich(GPR) mountains in the world, where vegetation restoration is key to safeguarding the environment. We reviewed the published literature and collected new data in order to analyze re-vegetation patterns and the status of plant communities in central Yunnan. The aim of our analysis was to suggest future improvements to restoration strategies in GPR mountain regions. Our results showed that spontaneous recovery was the most widespread type of restoration. N-fixing species such as Coriaria nepalensis and Alnus nepalensis play a vital role in succession. In the past, monoculture tree plantation was the primary method used in afforestation activities in central Yunnan; in recent years however, several different methods of restoration have been introduced including the use of agroforestry systems. For practical restoration, we found that spontaneous recovery was capable of delivering the best results, but that during its early stages, restoration results were affected by several factors including erosion risk, the origin of propagates and environmental variation. In contrast, methods employing human-made communities performed better in their early stages, but were constrained by higher costs and vulnerability to degradation and erosion. The use of N-fixing species such as A. nepalensis and Acacia mearnsii in plantations were unsuccessful in restoring full ecosystem functions. The success of restoration activities in GPR mountain regions could be improved through the following measures:(1) developing a better understanding of the respective advantages and disadvantages of current natural and human-engineered restoration approaches;(2) elucidating the feedback mechanism between phosphorus-rich soil and species selected for restoration, especially N-fixing species;(3) introducing market incentives aimed at encouraging specific restoration activities such as agroforestry, and improving the industry value chain.

关键词： Systematic review Dianchi Lake Fuxian Lake Natural restoration Human engineered restoration Floristic similarity

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The Role of Fracture Structure in Leachate Pollution at Landfills:A Case Study of a Landfill in Chongqing City

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Acta Geologica Sinica(English Edition) 2008年第5期82卷 1020-1026页

作者： LUO yunju liU Dongyan li Xiulan ZHU Zhengwei College of Civil Engineering Chongqing University Chongqing 400045

This paper studies a landfill where there are three faults running through. As serious pollution has occurred to the geological environment, the landfill is to be closed up and renovated. The paper aims to explore the role of fracture structure in leachate pollution at the landfill. The research was carried out in several stages. First, mathematical models of the pre-renovation landfill with three faults running through and the landfill after renovation were established. And then, the boundary conditions and parameters of the two mathematical models were determined. The groundwater level of the landfills was simulated in order to modify the two mathematical models. As a result, a feasible mathematical model was achieved. Based on this model, a comparison was made of the COD concentration variations in the inside leachate and outside leachate between the two landfills. Accordingly, the impacts of the fracture structure on the pollution of leachate at the landfills could be identified. The study results show that while faults contribute to the migration of ieachate, they also serve as a confluence of leachate, thus further deteriorating the environment. The COD concentrations of the inside leachate and the outside leachate of the pre-renovation landfill are respectively 800 mg/L and 220 mg/L higher than those of the post-renovation landfill. Therefore, measures must be taken to handle the ieachate seepage in areas where there are faults as well as the neighboring areas so as to get the environmental pollution under control.

关键词： landfill fracture structure leachate COD concentration seepage

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Determination of the ^(25)Mg(p,γ)^(26)Al resonance strength at E_(c.m.)=58 keV via shell model calculation

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Science China(Physics,Mechanics & Astronomy) 2015年第8期58卷 39-42页

作者： li ZhiHong SU Jun li yunju GUO Bing li ErTao WANG YouBao YAN ShengQuan liU WeiPing China Institute of Atomic Energy College of Physics Science and Technology Shenzhen University

The observation of 26Al is an useful tool for γ-ray astronomy and in studies of galactic chemical evolution. The most likely mechanism for 26Al nucleosynthesis is in the hydrogen burning MgAI cycle, and the 26Al production reaction 25Mg（p, γ）26Al at the important temperature range below T = 0.2 GK is still not well known. The spectroscopic factor of 58 keV resonance level in 26Al is determined with shell model calculation and then used to deduce the resonance strength of the 25Mg（p, γ）26Al reaction. The result provides a reference for the future 25Mg（p, γ）26Al direct measurement at Jinping underground laboratory.

关键词： γ-ray astronomy astrophysical reaction rate spectroscopic factor resonance strength

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Determination of the ^(12)C(p, γ)^(13)N reaction rates fromthe ^(12)C(~7li,~6He)^(13)N reaction

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 658-663页

作者： li ZhiHong, SU Jun, GUO Bing, li ZhiChang, BAI XiXiang, liU JianCheng, li yunju, YAN ShengQuan, WANG BaoXiang, WANG YouBao, liAN Gang, ZENG Sheng, li ErTao, CHEN YongShou, SHU NengChuan, FAN QiWen & liU WeiPing China Institute of Atomic Energy, Beijing 102413, China China Institute of Atomic Energy Beijing China

The angular distribution of the 12C(7li,6He)13N reaction at E(7li) = 44.0 MeV was measured at the HI-13 tandem accelerator of Beijing, China. The asymptotic normalization coefficient (ANC) of 13N → 12C + p was derived to be (1.64 ± 0.11) fm-1/2 through the distorted wave Born approximation (DWBA) analysis. The ANC was then used to deduce the astrophysical S (E) factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance.

关键词： the 12C(7li 6He)13N reaction DWBA analysis asymptotic normalization coefficient astrophysical S(E)-factor

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用于深地核天体物理实验的无窗气体靶差分结构和热效应研究

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原子能科学技术 2024年第S1期58卷 1-8页

作者：蒋宇辰连钢方晓李云居曹富强南巍曾晟谌阳平柳卫平中国原子能科学研究院北京102413 中山大学中法核工程与技术学院广东珠海519082 南方科技大学广东深圳518055

我国锦屏深地核天体物理(JUNA)平台是世界上束流强度最高的深地实验平台,为我国争取核天体物理国际领先地位提供了重要机遇。无窗气体靶是深地低能核天体物理实验测量的关键设备,可实现特定同位素参与核反应的直接测量,能有效拓展深地... 详细信息

我国锦屏深地核天体物理(JUNA)平台是世界上束流强度最高的深地实验平台,为我国争取核天体物理国际领先地位提供了重要机遇。无窗气体靶是深地低能核天体物理实验测量的关键设备,可实现特定同位素参与核反应的直接测量,能有效拓展深地实验的研究范围。国际上已有多家实验室将无窗气体靶应用于低能核反应的研究,但针对的都是较低流强的实验。为适应锦屏高功率强束流的实验需求,本工作设计可用于强流束的气体靶装置。通过Ansys Fluent和COMSOL软件模拟计算,验证了多级差分结构的可行性,并研究了靶厚的束流加热效应和量热器热效应,提出了无窗气体靶实验的设计优化方案,为后续JUNA深地实验研究的发展提供了可靠依据。

关键词：核天体物理深地实验室无窗气体靶低能核反应

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Empirical formula for β^--decay half-lives of r-process nuclei

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Science China(Physics,Mechanics & Astronomy) 2017年第8期60卷 21-27页

作者： Yong Zhou ZhiHong li YouBao Wang YongShou Chen Bing Guo Jun Su yunju li ShengQuan Yan XinYue li ZhiYu Han YangPing Shen lin Gan Sheng Zeng Gang lian WeiPing liu China Institute of Atomic Energy

Experimental data ofβ--decay half-lives of nuclei with atomic number between 20 and 190 are investigated.A systematic formula has been proposed to calculateβ^--decay half-lives of neutron-rich nuclei,with a particular consideration on shell and pair effects,the decay energy Q as well as the nucleon numbers(Z,N).Although the formula has relatively few parameters,it reproduces the experimentalβ^--decay half-lives of neutron-rich nuclei very *** predicted half-lives for the r-process relevant nuclei obtained with the current formula serve as reliable input in the r-process model calculations.

关键词： β--decay half-lives neutron-rich nuclei r-process

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Parametrization of woods-saxon potential for heavy-ion systems

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Science China(Physics,Mechanics & Astronomy) 2017年第8期60卷 28-34页

作者： lin Gan ZhiHong li HuiBin Sun DanYang Pang Bing Guo yunju li Jun Su ShengQuan Yan ErTao li YouBao Wang Gang lian ZhiYu Han XinYue li DongHui li Tianli Ma ChangJin Pei YangPing Shen Yi Su Sheng Zeng Yong Zhou WeiPing liu China Institute of Atomic Energy College of Physics and Energy Shenzhen University School of Physics and Nuclear Energy Engineering Beihang University

Several elastic scattering angular distributions of 12C from target nuclei of A≥ 39 are analyzed to extract the Woods-Saxon poten- tial parameters with the fixed imaginary potential and Coulomb radius parameters. Using the best fitted diffuseness parameters, the correlations of the real part parameters with A1/3 1 ＋ A1/3 2and incident energy are revealed, and the systematic Woods-Saxon potential parameters are presented for nucleus-nucleus interaction. The proposed potential parameters can reproduce not only the elastic scattering angular distributions induced by 12C, but also many elastic scattering angular distributions induced by the projectiles other than 12C, thus providing important inputs for the study of nuclear reactions of heavy-ion systems.

关键词： optical potential elastic scattering heavy-ion reactions

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115份设施番茄表型性状遗传多样性分析

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江苏农业学报 2024年第8期40卷 1361-1370页

作者：谢雪果彭晓云李云驹张白鸽汤俊瑜施延达冯元姣常静静许玲于冬冬云南智农高新技术有限公司云南昆明650600 广东省农业科学院蔬菜研究所/广东省蔬菜新技术研究重点实验室广东广州510640 云南云天化现代农业发展有限公司云南昆明650600 昆明市晋宁区农业特色产业服务中心云南昆明650600

种质资源是新品种选育的根本。为筛选适宜云南省设施栽培的、农艺性状优良的番茄种质,本研究引进115份番茄种质,对其质量性状和数量性状进行了调查,并利用主成分分析、相关性分析和聚类分析对种质资源的遗传多样性和特征规律进行研究。... 详细信息

种质资源是新品种选育的根本。为筛选适宜云南省设施栽培的、农艺性状优良的番茄种质,本研究引进115份番茄种质,对其质量性状和数量性状进行了调查,并利用主成分分析、相关性分析和聚类分析对种质资源的遗传多样性和特征规律进行研究。本研究筛除了9份极易感病的番茄种质,余下的106份中筛选出86份抗病种质;106份番茄种质均为蔓生型,其果实形状及颜色比较丰富,共有3种果型、7种果色;植株长势整齐度高的种质共计15份,无裂果及裂果程度中等的种质共计35份。其中,番茄种质的心室数、单果重、首花序节位性状的变异幅度较大。相关性分析结果表明,株高与可溶性固形物含量、转色总台数、坐果总台数和总台数呈极显著正相关,与单果重和单株产量呈极显著负相关;茎粗与单花序坐果数、可溶性固形物含量、转色总台数、坐果总台数和总台数呈极显著正相关,与单果重和单株产量呈极显著负相关。聚类分析将番茄种质分为3个类群6个亚群,筛选出平均可溶性固形物含量高、平均单花序坐果数多和平均坐果总台数多的番茄种质共计47份;平均单株产量大于5.00 kg的番茄种质23份;平均单果重大于200.00 g的番茄种质9份。分析结果表明,番茄首花序节位越高坐果总台数越少;单果重越大,可溶性固形物含量越低,单株产量越高,单花序坐果数越少。果实横径、果梗洼大小、单果重、果实纵径和果肉厚度可作为评价设施番茄种质的主要因子。

关键词：设施番茄变异系数主成分分析相关性分析聚类分析

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磷基材料修复铅锌矿山重金属污染研究进展

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盐湖研究 2024年第4期32卷 122-132页

作者：吴高阳王磊余浪肖亚楠周金华李云驹陈忠昆明理工大学国土资源工程学院云南昆明650093 云南磷化集团公司国家磷资源开发利用工程技术研究中心云南昆明650600

铅锌矿是典型的有色金属矿,铅锌矿的开采很容易产生重金属的污染。针对开采过程中形成的Pb、Zn、Cd、Cu等污染,磷基材料对其有很好的修复效果。文章对修复铅锌矿重金属污染的磷基材料进行了较为系统的总结。按照磷基物质来源,主要划分... 详细信息

铅锌矿是典型的有色金属矿,铅锌矿的开采很容易产生重金属的污染。针对开采过程中形成的Pb、Zn、Cd、Cu等污染,磷基材料对其有很好的修复效果。文章对修复铅锌矿重金属污染的磷基材料进行了较为系统的总结。按照磷基物质来源,主要划分为天然物质和人工制剂两大类。磷基物质修复Pb的机制有吸附、表面络合以及形成沉淀等,以沉淀作用为主;修复Cd的机制主要为表面络合和共沉淀,较高的pH值使Cd更易形成沉淀;修复Zn、Cu、Ni的机制主要以表面配位、离子交换和生成非晶体物质为主。磷基材料修复铅锌尾矿重金属的影响因素非常多,影响方式也很复杂,包括各种阴阳离子、pH值、含磷物质的形态和用量、重金属的形态和初始浓度等。各影响因子对不同磷基物质修复效果的影响具有复杂性,这跟磷基物质的多样性,性质差异大有关。目前,磷基物质修复铅锌矿重金属污染的研究仍在理论探索层面,实际应用方面略显不足。未来需要对修复效果的影响因素及微界面过程进行进一步的研究,并加强实际应用推广。

关键词：磷基材料重金属污染修复铅锌矿山 Pb、Zn、Cd、Cu重金属

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Leucine regulates lipid metabolism in adipose tissue through adipokine-mTOR-SIRT1 signaling pathway and bile acid—microbe axis in a finishing pig model

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Animal Nutrition 2024年第1期16卷 158-173页

作者： yunju Yin Saiming Gong Mengmeng Han Jingzun Wang Hanjing Shi Xianji Jiang liu Guo Yehui Duan Qiuping Guo Qinghua Chen Fengna li Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesHunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic ProcessHunan Provincial Engineering Research Center for Healthy Livestock and Poultry ProductionChangsha 410125China College of Animal Science and Technology Hunan Agricultural UniversityChangsha 410128China College of Modern Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China College of life Science and Engineering Northwest Minzu UniversityLanzhou 730124China College of life Sciences Hunan Normal UniversityChangsha 410128China

This study was conducted to explore the regulatory mechanism of leucine(Leu)on lipid metabolism of finishing ***-four Duroc×Landrace×Large cross pigs with an average body weight of68.33±0.97 kg were randomly allocated into 3 treatment groups with 8 replicates per group(1 pig per replicate).The dietary treatments were as follows:control group(CON),0.25%Leu group and 0.50%Leu *** experimental period was 42 *** results showed as follows.(1)Compared with the CON,0.25%and 0.50%Leu increased(Pliferatoractivated receptorγ(PPARγ)were decreased but the level of fatty acid binding protein 4(FABP4)and fatty acid translocase(FAT/CD36)were increased in backfat *** the 0.25%Leu group,the protein levels of p-Rictor,p-Raptor,p-eIF4E-binding protein 1(p-4EBP1),p-silent mating type information regulator 2homolog 1(p-SIRT1)and acetylation ribosome s6 protein kinase 1(Ac—S6K1)were increased(Plites were screened out from the serum of finishing pigs including allolithocholic acid(alloLCA),isolithocholic acid(isoLCA),ursodeoxycholic acid(UDCA)and hyodeoxycholic acid(HDCA),which correlate to various degrees with the above *** conclusion,Leu could promote adipose tissue lipolysis of finishing pigs through the mTOR-SIRT1 signaling pathway,a

关键词： Leu lipid metabolism Gut microbiota Bile acid

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