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Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

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Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU Jian LIU shangbin HE Xiufeng yang Huashan DOU Honghai ZHANG School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

Polar plumes observed at the total solar eclipse in 2009

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Science China(Physics,Mechanics & Astronomy) 2011年第10期54卷 1906-1910页

作者： yang ShuHong ZHANG Jun ZHANG ZhiYong ZHAO ZhaoWang LIU yangBing SONG Qian yang shangbin BAO XingMing LI LePing CHU Zhe LI Ting Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

During the total solar eclipse of July 22, 2009, we carried out a white-light observation in Anji, Zhejiang, China. The aim wasto observe the polar plumes (PPs) with high spatial and temporal resolutions in white-light. With the observational data, weinvestigate the properties and evolution of the PPs and compare them with those of the low-latitude plumes (LPs). We find thatboth the PPs and the LPs have comparable lengths and widths, and the mean length and width are 300 Mm and 16 Mm, re-spectively. The average inclination angle (13 degree) of the PPs is smaller than that (32 degree) of the LPs. Generally, theplumes which are closer to the coronal hole center are more vertical. We trace the PPs and the LPs in the sequence of imagesand find that none of them disappears and no new one is created. Additionally, neither plasma outflow nor transverse oscilla-tion is observed. These imply that the evolution process of plumes is much longer than the timescale of eclipse.

关键词：观测数据极地日全食 PPS LPS 等离子流安吉县浙江省

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太阳空间探测进展与展望

中国空间科学技术 2022年第5期42卷 1-10页

作者：杨孟飞代树武王颖朱成林杨尚斌张也弛中国空间技术研究院北京100094 北京空间飞行器总体设计部北京100094 中国科学院国家天文台北京100101

为了探索太阳空间探测活动的发展方向,在广泛调研太阳空间探测任务的基础上,综合考虑任务实施年代、轨道设计、探测要素、技术特点和成果影响力,选取了10个典型空间太阳探测器,对其科学目标、有效载荷、卫星平台特性和科学发现进行了分... 详细信息

为了探索太阳空间探测活动的发展方向,在广泛调研太阳空间探测任务的基础上,综合考虑任务实施年代、轨道设计、探测要素、技术特点和成果影响力,选取了10个典型空间太阳探测器,对其科学目标、有效载荷、卫星平台特性和科学发现进行了分析,提炼总结了太阳空间探测的进展和发展趋势。总体而言,太阳探测器运行轨道逐步多样化,有效载荷探测要素更加丰富,探测精度、时空分辨率等显著提升,但仍存在大量问题待解决。在分析现阶段成果和待解决问题的基础上,提出了太阳空间探测的发展展望,指出了全方位、多要素探测是破解太阳物理和空间天气预报发展瓶颈的可行途径。

关键词：太阳空间探测太阳物理空间天气预报轨道设计卫星平台有效载荷

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湖、库水体CH_(4)冒泡排放研究进展

湖泊科学 2024年第2期36卷 339-352页

作者：康满春刘流刘佳肖尚斌三峡大学三峡库区生态环境教育部工程研究中心宜昌443002 三峡水库生态系统湖北省野外科学观测研究站宜昌443002 云南师范大学高原地理过程与环境变化云南省重点实验室昆明650500

冒泡排放是湖、库水体CH_(4)排放的主要方式之一,其排放通量和占CH_(4)总排放量比例均具有极其显著的时空差异性,是当前水体CH_(4)排放估算不确定性的主要来源之一。然而,目前关于湖、库水体CH_(4)冒泡排放通量监测、时空分布规律、过... 详细信息

冒泡排放是湖、库水体CH_(4)排放的主要方式之一,其排放通量和占CH_(4)总排放量比例均具有极其显著的时空差异性,是当前水体CH_(4)排放估算不确定性的主要来源之一。然而,目前关于湖、库水体CH_(4)冒泡排放通量监测、时空分布规律、过程机制和模型模拟的系统梳理鲜有报道。本研究对比了目前水体CH_(4)冒泡的监测方法技术的适用性及优缺点,分析总结湖、库水体CH_(4)冒泡排放及通量的时空分布特征,梳理CH_(4)气泡在沉积物-水体中的产生-成长-迁移-释放的过程、影响因素及模型,并提出了水体CH_(4)冒泡过程模型框架。最后,本研究提出未来研究应基于湖、库水体分类、设备开发和改进来构建适应性的湖、库水体CH_(4)冒泡排放监测标准体系,开发基于过程的CH_(4)冒泡机理模型,为认识变化环境下湖、库水体CH_(4)冒泡过程和准确估算CH_(4)排放量提供支撑。

关键词：甲烷冒泡排放湖泊水库气泡模型

新形势下地方税源建设的现状、困境与路径选择

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国际税收 2024年第2期 20-30页

作者：宋尚彬郭健上海财经大学公共经济与管理学院山东财经大学财政税务学院

地方税源建设是发挥财政治理职能、维持财政运行可持续、健全地方税体系的重要举措。新形势下地方税源规模、结构、地区分布等都发生了变化,地方税源建设面临新困境。本文认为,健全地方税体系重在培育地方税源,具体应从确立地方主体税... 详细信息

地方税源建设是发挥财政治理职能、维持财政运行可持续、健全地方税体系的重要举措。新形势下地方税源规模、结构、地区分布等都发生了变化,地方税源建设面临新困境。本文认为,健全地方税体系重在培育地方税源,具体应从确立地方主体税种、合理赋予地方税权,改革实体税收制度、适应数字经济税源等方面探索地方税源建设的路径,以充实地方税收收入。

关键词：地方税体系地方税源建设数字经济产业结构

Cross Sections of 14 MeV Neutron Induced Reactions on Wolfram Isotopes

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中国核科技报告 1997年第S3期 15-18页

作者： Kong Xiangzhong Hu shangbin yang Jingkang (Department of Modern Physics, Lanzhou University, Lanzhou, 730001)

Introduction The importance of nuclear data for fusion power reactor design has been acknowledged, in particular for safety, environment reasons and economics. The 14 MeV neutron activation cross sections are the key nuclear data for environmental impact, material recycling, waste handling. Due to the large number of materials and traces of alloy elements and contamination, there are requirements for a complete database covering large number of nuclides. Problems still exist for some reactions, for example, forW(n,n′α)Hf reaction only one measurement was published,

关键词： In Cross Sections of 14 MeV Neutron Induced Reactions on Wolfram Isotopes

花瓣形钢管混凝土柱轴压受力机理和承载力研究

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建筑钢结构进展 2024年第3期26卷 70-79页

作者：张涛甘丹李扬黄辉辉黄尚斌重庆大学土木工程学院重庆400045 四川省建筑设计研究院有限公司成都610095 广东省建筑设计研究院有限公司广州510010 同创汇运营管理有限公司广州510315

花瓣形钢管混凝土柱具有造型美观的优点,为具体研究其受力机理和承载力,定义了其截面组成,提出了截面偏移比和截面对称系数以反映花瓣形截面性质,提出在花瓣柱中设置十字形加劲肋以增强其组合效应。基于某工程中墩柱和有限元模型,研究... 详细信息

花瓣形钢管混凝土柱具有造型美观的优点,为具体研究其受力机理和承载力,定义了其截面组成,提出了截面偏移比和截面对称系数以反映花瓣形截面性质,提出在花瓣柱中设置十字形加劲肋以增强其组合效应。基于某工程中墩柱和有限元模型,研究了花瓣形钢管混凝土短柱在轴压荷载作用下的受力机理,分析了加劲肋厚度、混凝土强度、钢材强度、加劲肋开孔直径和间距等参数对轴压性能的影响,研究了加劲肋厚度与钢管壁厚的匹配关系。根据理论分析和大量有限元参数分析结果,建议了加劲肋厚度与钢管壁厚之比和钢管名义径厚比的取值范围,提出了花瓣形钢管混凝土短柱的轴压承载力计算式。

关键词：花瓣形钢管混凝土柱组合效应多腔钢管混凝土加劲肋有限元分析

Research and application of composite stochastic resonance in enhancement detection

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Chinese Physics B 2024年第1期33卷 264-273页

作者：高蕊焦尚彬薛琼婕 School of Automation and Information Engineering Xi'an University of TechnologyXi'an 710048China School of Electronic and Electrical Engineering Baoji University of Arts and SciencesBaoji 721016China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of TechnologyXi'an 710048China

Aiming at the problem that the intermediate potential part of the traditional bistable stochastic resonance model cannot be adjusted independently, a new composite stochastic resonance(NCSR) model is proposed by combining the Woods–Saxon(WS) model and the improved piecewise bistable model. The model retains the characteristics of the independent parameters of WS model and the improved piecewise model has no output saturation, all the parameters in the new model have no coupling characteristics. Under α stable noise environment, the new model is used to detect periodic signal and aperiodic signal, the detection results indicate that the new model has higher noise utilization and better detection effect.Finally, the new model is applied to image denoising, the results showed that under the same conditions, the output peak signal-to-noise ratio(PSNR) and the correlation number of NCSR method is higher than that of other commonly used linear denoising methods and improved piecewise SR methods, the effectiveness of the new model is verified.

关键词： Woods–Saxon improved piecewise model composite stochastic resonance(SR) image denoising

Cross Section Measurement for Reaction 193Ir(n,2n)192m2Ir at 14.7 MeV

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中国核科技报告 1996年第S2期 22-25页

作者： Kong Xiangzhong Wang Yongchang Hu shangbin yang Jingkang (Department of Modern Physics, Lanzhou University, Lanzhou)

The cross sections induced by neutron on long-lived radionuclides of importance in fusion reactor technology are measured by activation method forIr(n,2n)Ir reaction at 14.7 MeV. The neutron fluences are determined by the cross section ofNb(n,2n)Nb. The neutron energies in these measurements are determined by cross section ratios forZr(n,2n)zr andNb(n,2n)Nb reactions.

关键词： Cross Section Measurement for Reaction n,2n Ir Ir at 14.7 MeV