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Agricultural Land Suitability of Production Space in the Taihang Mountains, China

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Chinese Geographical Science 2019年第6期29卷 1024-1038页

作者： GENG Shoubao SHI Peili zong ning ZHU Wanrui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

The contradiction between the shortage of land for agriculture due to rapid expansion of industrialization and urbanization and increasing population pressure is projected to impose great threats to future food security.Agricultural land suitability evaluation is an effective approach to improve the utilization of land resources for crop production and thus enhance the capacity of food provision.In this study, we evaluated the land suitability for agriculture of the production space in the Taihang Mountains by three steps: establishing indicator system, determining weights for indicators, and constructing a fuzzy matter-element model to assess the grades of suitability.Results showed that the land suitability had a significant linear correlation with potential crop yields, indicating our evaluation was effective to predict crop production.The spatial pattern of land suitability for crop production demonstrated that land with higher suitability was generally located in piedmont plains and basins, while land with lower suitability was mostly situated in mountainous areas.The area of highly, moderately, marginally suitable and unsuitable land for agriculture was 32.13%, 28.58%, 37.49% and 1.80% of the production space, respectively.However, the correlation degree analysis indicated that the requirements of these four suitability grades were currently not satisfied but could be potentially fulfilled.In terms of indicator weights, soil properties were much more important than topography and location conditions to influence the grades of suitability.Among all indicators, slope, soil organic matter, soil texture and soil depth were the most influential factors, so slope farming prevention and organic fertilization were most likely to improve land suitability for agriculture.Compared the outputs of our land suitability evaluation model with the distribution of the existing croplands, we found that about 66.52% of marginally suitable and 54.55% of unsuitable land for agriculture were currently used for croplands.Therefore

关键词： agricultural land suitability matter-element model production space the Taihang Mountains

传播的负性偏向:网络政治安全风险识别及消解理路

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哈尔滨工业大学学报（社会科学版） 2024年第2期26卷 34-42页

作者：张爱军宗雅宁西北政法大学新闻传播学院(艺术学院) 西安710122 西北政法大学网络政治传播研究院西安710122

网络政治安全是政治安全的组成部分,是政治传播安全在互联网场域的延伸和扩展。网络政治传播安全本应创造新型政治文明生态。多元主体与社会因素相互作用、相互交织,打破了网络政治传播安全应有的稳定性,带来网络政治安全的负性偏向传... 详细信息

网络政治安全是政治安全的组成部分,是政治传播安全在互联网场域的延伸和扩展。网络政治传播安全本应创造新型政治文明生态。多元主体与社会因素相互作用、相互交织,打破了网络政治传播安全应有的稳定性,带来网络政治安全的负性偏向传播风险。在个体心理认知建设、社会公共服务建设、国家政治制度建设三者的影响下,出现网络政治安全的偏向传播。网络政治安全面临着技术偏向传播中的民主失序、权力偏向传播中的结构极化、意识形态偏向的参与抗争、地缘偏向的政治龃龉四个层次的负性偏向传播风险。应该通过适应性治理平衡技术幻象、调控规制平衡公权力监督、群己共协平衡意识形态撕裂、善政平衡圈地隐忧,对网络政治安全的负性偏向传播风险进行责任治理等,不断推进网络政治安全。

关键词：偏向传播政治安全互联网风险治理地缘政治

Prognostic value of plasma C-reactive protein in the evaluation of paraquat poisoning patients

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Asian Pacific Journal of Tropical Biomedicine 2015年第10期5卷 841-844页

作者： zong ning Yu-Long Bai Hua Lu Kang-Lin Mo Department of Emergency The First Affiliated Hospital of Guangxi Medical University

Objective: To investigate the prognostic value of plasma C-reactive protein(CRP) level in patients with paraquat poisoning.Methods: This study included 162 patients with paraquat poisoning. The data of plasma paraquat, CRP level and arterial blood gas were analyzed. Cox regression analysis was applied to evaluate the risk factors of prognosis. Receiver operating characteristics curve analysis and area under curve were used to calculate the predictive power of significant variable. Differences in patient survival were determined using the Kaplan–Meier method and a log-rank test.Results: Plasma CRP level was significantly increased in non-survival patients compared with survival patients(P ning, and the plasma CRP level may be useful for the prediction of prognosis in paraquat poisoning.

关键词： paraquat poisoning prognosis prognostic mortality

中空纤维液相微萃取-气相色谱-质谱联用法测定纺织品中的芳香胺

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化学研究与应用 2024年第5期36卷 1143-1147页

作者：麦宝华郭宗宁禹伟腾深圳市检验检疫科学研究院广东深圳518010 黄埔海关技术中心广东东莞523071 深圳海关工业品检测技术中心广东深圳518067

本文结合中空纤维液相微萃取(HF-LPME)与气相色谱-质谱(GC-MS)联用技术,建立了纺织品中邻氨基苯甲醚、2-甲氧基-5-甲基苯胺、2-萘胺、4-氨基联苯、3,3’-二氯联苯胺5种芳香胺类物质的分析方法。优化后的液相微萃取条件:样品溶液pH调节为... 详细信息

本文结合中空纤维液相微萃取(HF-LPME)与气相色谱-质谱(GC-MS)联用技术,建立了纺织品中邻氨基苯甲醚、2-甲氧基-5-甲基苯胺、2-萘胺、4-氨基联苯、3,3’-二氯联苯胺5种芳香胺类物质的分析方法。优化后的液相微萃取条件:样品溶液pH调节为12,以甲苯为萃取溶剂,在室温及300 rpm搅拌速度下,萃取30min。富集倍数最高能达185倍。方法的检测线性范围0.05~10μg·mL^(-1),检出限均低于10 ng·mL^(-1),精密度(RSD,n=6)为3.8~7.9%,回收率为84.0~119.8%。

关键词：中空纤维液相微萃取气相色谱质谱偶氮染料芳香胺纺织品

双重孔结构SiO_(2)的制备及其吸附生物大分子的性能

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应用化工 2024年第3期53卷 520-524页

作者：赵俊琦李昕孙斌张晓昕宗保宁中石化石油化工科学研究院有限公司石油化工分子转化与反应工程全国重点实验室北京100083

采用十六烷基三甲基溴化铵作为有序介孔模板剂和相分离诱导剂,通过相分离和溶胶-凝胶转化,合成了具有较小有序介孔和较大堆积介孔/大孔的双重孔结构SiO_(2)。结果表明,采用该双重孔结构SiO_(2)吸附模型生物大分子,其吸附量明显高于单一... 详细信息

采用十六烷基三甲基溴化铵作为有序介孔模板剂和相分离诱导剂,通过相分离和溶胶-凝胶转化,合成了具有较小有序介孔和较大堆积介孔/大孔的双重孔结构SiO_(2)。结果表明,采用该双重孔结构SiO_(2)吸附模型生物大分子,其吸附量明显高于单一孔结构MCM-41型SiO_(2),显示双重孔结构SiO_(2)吸附大分子的优势。

关键词：模板剂相分离有序介孔双重孔结构SiO_(2)材料生物大分子

藏北两个临近不同高寒草地碳通量对气候条件的响应

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草业学报 2024年第6期33卷 1-16页

作者：徐玲玲牛犇张宪洲何永涛石培礼宗宁武建双王向涛中国气象局国家气象中心北京100081 中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室拉萨高原生态试验站北京100101 中国科学院大学资源与环境学院北京100049 中国农业科学院农业环境与可持续发展研究所北京100081 西藏农牧学院动物科学学院西藏林芝860000

生态系统碳循环应对气候变化的敏感性研究是“碳中和”背景下的重要议题。青藏高原高寒草地面积广阔,碳储量丰富,脆弱性高,近年来随着观测技术尤其是涡度相关技术和模拟技术的发展,已有不少研究致力于揭示青藏高原高寒草地生态系统碳水... 详细信息

生态系统碳循环应对气候变化的敏感性研究是“碳中和”背景下的重要议题。青藏高原高寒草地面积广阔,碳储量丰富,脆弱性高,近年来随着观测技术尤其是涡度相关技术和模拟技术的发展,已有不少研究致力于揭示青藏高原高寒草地生态系统碳水通量对气候变化的响应过程。但是,相同气候背景下不同高寒草地类型对环境变化的响应规律及敏感性尚不清楚。本研究基于藏北高原两个临近的高寒草地生态系统,高寒草甸和高寒湿地涡度相关观测的碳水通量数据,对比分析了不同水分条件下藏北高寒草甸和高寒湿地碳循环的气候敏感性。结果表明,高寒草甸的碳交换量要显著小于高寒湿地,高寒草甸是碳中性的,年净CO_(2)交换量为(18.09±40.66) g C·m^(-2) ,而高寒湿地是稳定的碳汇,年净CO_(2)固定量为(155.09±32.85)g C·m^(-2) 。水分条件对高寒草甸和高寒湿地植被光响应曲线最大的光合速率(α)的影响较弱,与饱和光强下的总初级生产力(Amax)呈显著正相关关系。水分对生态系统呼吸与温度的指数响应关系的调节作用主要体现在基础呼吸值(a)上,高寒湿地a的均值是高寒草甸的3.76倍,而对两个高寒草地生态系统呼吸敏感性(Q10)的调节均不显著。高寒草甸和高寒湿地Q10的均值(1.84)以及随温度升高而减小的趋势基本一致。藏北高寒草地生态系统的碳源汇特征对环境因子的响应取决于多因素共同限制,因此,基于区域性的联网协同观测有助于更加清晰地理解高寒生态系统碳交换响应气候变化的机理。

关键词：碳循环高寒草地气候敏感性藏北高原

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Statistical properties of radio flux densities of solar flares

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Research in Astronomy and Astrophysics 2020年第11期20卷 239-251页

作者： Lu Wang Si-Ming Liu zong-Jun ning Purple Mountain Observatory Nanjing 210000China Key Laboratory of Dark Matter and Space Astronomy Nanjing 210000China University of Science and Technology of China Heifei 100049China

Short timescale flux variations are closely related to the energy release process of magnetic reconnection during solar flares.Radio light curves at 1,2,3.75,9.4,and 17 GHz of 209 flares observed by the Nobeyama Radio Polarimeter from 2000 to 2010 are analyzed with a running smooth technique.We find that the impulsive component(with a variation timescale shorter than 1 s)of 1 GHz emission of most flares peaks at a few tens of solar flux unit and lasts for about 1 minute and the impulsive component of 2 GHz emission lasts a shorter period and peaks at a lower flux level,while at the three high frequency channels the occurrence frequency of flares increases with the decrease of the flux density up to the noise level of the corresponding background.However,the gradual components of these emissions have similar duration and peak flux density distributions.We also derive the power spectrum on different timescales and a normalized wavelet analysis is used to confirm features on short timescales.At a time resolution of 0.1 s,more than^60%of these radio light curves show significant flux variation on 1 s or shorter time scales.This fraction increases with the decrease of frequency and reaches^100%at 1 GHz,implying that short timescale processes are universal in solar flares.We also study the correlation between the impulsive radio flux densities and soft X-ray fluxes obtained with the GOES satellites and find that more than 65%of the flares with an impulsive component have their impulsive radio emission reach a peak value ahead of the soft X-ray fluxes and this fraction increases with the radio frequency.

关键词： methods data analysis Sun flares Sun radio radiation

The impact of turbulence on electron heating and acceleration near the neutral point of externally driven reconnecting current sheets in solar flares

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Research in Astronomy and Astrophysics 2012年第12期12卷 1701-1713页

作者： Gui-Ping Wu Hai-Sheng Ji zong-Jun ning Department of Physics Southeast University Nanjing 210096 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

We aim to investigate the influence of plasma instability on electron acceleration and heating near the neutral point of a turbulent reconnecting current sheet （RCS）.Through numerically solving the one dimensional relativistic Vlasov equation with typical solar coronal parameters and a realistic mass ratio in the presence of a strong inductive electric field E0,we suggest that the wave-particle scattering may produce a flat electron flux spectrum from thermal to nonthermal electrons without a sudden low-energy cutoff in the acceleration region.The ratio between electron heating and acceleration decreases with the increase of the induced electric field.It is about one for E0=1 V cm-1 and one fourth for E0=10 V cm-1.The unstable waves excited by the beam plasma instability first accelerate the electrons,then trap these electrons from further acceleration by an induced electric field through wave-particle resonant interactions.

关键词： turbulence-scattering-Sun：X-rays,gamma rays-acceleration of particles

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优势种对藏北草原群落稳定性具有主导作用

Journal of Plant Ecology 2023年第3期16卷 165-176页

作者： Ge Hou Peili Shi Tiancai Zhou Jian Sun ning zong Minghua Song Xianzhou Zhang Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

优势种作为群落动态和生态系统的重要驱动因素,对生物条件以及与其他物种的相互作用具有强烈的影响,这一现象在高寒草地生态系统中尤其明显。然而,不同生态系统中优势种对群落稳定性的影响作用却知之甚少。本文研究了藏北草原4大高寒草... 详细信息

优势种作为群落动态和生态系统的重要驱动因素,对生物条件以及与其他物种的相互作用具有强烈的影响,这一现象在高寒草地生态系统中尤其明显。然而,不同生态系统中优势种对群落稳定性的影响作用却知之甚少。本文研究了藏北草原4大高寒草地(高寒草甸、高寒草甸草原、高寒草原和高寒荒漠草原)地上生产力的时间稳定性(2014-2020年)和群落稳定性机制,并分析了群落特征和物种组成的变化。研究结果表明,高寒草甸的群落稳定性显著高于其他3种草地。这种差异主要归因于高寒草甸较高的补偿效应和选择效应。此外,优势种通过增加其稳定性和异步性来维持群落稳定性。这些研究结果表明了优势种作为群落的基础物种,可能在塑造高寒草原群落稳定性方面发挥着主导作用。因此,在日益加剧的环境波动下,保护优势种对于脆弱生态系统稳定生态系统功能至关重要。

关键词：群落稳定性物种丰富度优势种补偿效应选择效应