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Comparison of the spatial and temporal variability of macroinvertebrate and periphyton-based metrics in a macrophyte-dominated shallow lake

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Frontiers of Earth Science 2015年第1期9卷 137-151页

作者： Lulu ZHANG jingling liU Yi li State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

The influence of spatial differences, which are caused by different anthropogenic disturbances, and temporal changes, which are caused by natural conditions, on macroinvertebrates with periphyton communities in Baiyangdian Lake was compared. Periphyton and macrobenthos assemblage samples were simultaneously col- lected on four occasions during 2009 and 2010. Based on the physical and chemical attributes in the water and sediment, the 8 sampling sites can be divided into 5 habitat types by using cluster analysis. According to coefficients variation analysis （CV）, three primary conclusions can be drawn ：（1） the metrics of Hilsenhoff Biotic Index （HBI）, Percent Tolerant Taxa （PTT）, Percent dominant taxon （PDT）, and community loss index （Cli）, based on macroinvertebrates, and the metrics of algal density （AD）, the proportion of chlorophyta （CHL）, and the proportion of cyanophyta （CYA）, based on periphytons, were mostly constant throughout our study; （2） in terms of spatial variation, the CV values in the macroinvertebratebased metrics were lower than the CV values in the periphyton-based metrics, and these findings may be caused by the effects of changes in environmental factors; whereas, the CV values in the macroinvertebrate-based metrics were higher than those in the periphyton-based metrics, and these results may be linked to the influences of phenology and life history patterns of the macroinvertebrate individuals; and （3） the CV values for the functionalbased metrics were higher than those for the structuralbased metrics. Therefore, spatial and temporal variation for metrics should be considered when assessing applying the biometrics.

关键词： Baiyangdian Lake biomonitoring coefficient variation structural metrics functional metrics

Effects of fertigation strategies on water and nitrogen distribution under water storage pit irrigation for orchards

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International Journal of Agricultural and Biological Engineering 2018年第1期11卷 165-171页

作者： jingling li Pan Chen Xihuan Sun Ping liu College of Water Resource Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Water storage pit(WSP)irrigation is a simple and inexpensive technology suitable for orchards in semiarid and arid regions of North *** study compared the effects of different fertigation strategies on water and nitrogen distribution,and ammonia volatilization.A fertigation experiment was conducted using a 30°wedge-shaped plexiglass soil container,which represents one-twelfth of the complete storage *** height of the container was 120 cm,and a plexiglass damper for simulating the zero flux plane of adjacent water storage pits was located at the 40 cm *** fertigation strategies were used for WSP irrigation:solution application during the first half(N-W),the last half(W-N),the middle half of an irrigation cycle(W-N-W),and during the entire irrigation(N-N).Surface(SF)irrigation was used as a control treatment with solution application during the entire irrigation(SN-N).The experimental results showed that the soil water and ammonium contents at 0-10 cm soil depth under WSP irrigation were only 10.51%and 18.42% of those under SF irrigation,*** cumulative NH3 volatilization under WSP irrigation was 51.71%-68.72% lower compared with that under SF *** soil water distributions were similar for all four fertigation ***3 volatilization mainly occurred at the pit wall interface,and cumulative NH3 volatilization loss followed the trend N-N>W-N>W-N-W>*** was adsorbed into the soil and thus mostly remained near the pit *** concentrations of ammonium were found near the edge of the wetting zone under all *** to N-W,N-N and W-N-W treatments,W-N treatment decreased the nitrate accumulation at 80-90 cm by 38.6%,19.0%and 10.3%,*** W-N strategy was suggested for minimizing potential nitrate leaching.

关键词： water storage pit fertigation soil water nitrogen distribution orchards irrigation

Characteristic analysis of ecosystem service value of water system in Taiyuan urban district based on LUCC

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International Journal of Agricultural and Biological Engineering 2016年第1期9卷 153-165页

作者： liu Ping Zheng Xiuqing Chen Junfeng Zhang Qing li jingling Wu Bo College of Water Resources Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Changes in the land use and ecosystem service value of the 600 m buffer zone of Jinyang Lake and the 1000 m riparian zone of the Fenhe River in the Taiyuan urban district in China,were studied using satellite image data collected in June 2006 and June *** to the ecosystem services assessment system based on expert knowledge,the ecosystem service value(ESV)per unit area was determined for various land-use types and the value of the water system and its buffer regions in the Taiyuan urban district were *** then the relationship between LUCC(Land Use/Cover Change)and ESV was ***,the accuracy and validity of the results was *** results showed that:(1)the areas of green vegetation and water bodies of Jinyang Lake and its buffer region decreased by 24.96%and 3.22%,respectively,between June 2006 and June 2013,whereas the areas of farmland and built-up land increased by 15.81%and 12.37%,*** Jinyang Lake,the degree of dynamic change for green vegetation,water bodies,farmland,built-up land,and unused land was−0.13,−0.02,0.17,0.09,and−0.05,*** the Fenhe River’s buffer region,the areas of green vegetation,farmland and unused land decreased by 1.36%,6.36%and 0.3%,respectively,but those of built-up land and water bodies increased by 1.41%and 6.61%,*** degree of dynamic change was−0.03,−0.02,−0.04,0.01 and 0.32,respectively;(2)In 2006,the landscape fragmentation indices(LFI)of Jinyang Lake buffer of 0-200 m zone were greater than 2,but those of 200-600 m buffer zone were less than 0.3,the water-body index not ***,in 2013,the landscape fragmentation indices of green vegetation and water bodies of 0-600 m buffer zone were both high,meaning that the land-use pattern had *** fragmentation index of green vegetation of the 0-200 m buffer increased from 0.1(the minimum for the year)to 1.7(the maximum for the year)during the seven years of this study along the Fenhe *** fragmen

关键词： remote sensing water system land use LUCC ecosystem service value urban

Dual-services generation using an integrated polarization multiplexing modulator

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Chinese Optics Letters 2020年第11期18卷 27-31页

作者： Feng Zhao Jianjun Yu jingling li School of Electronic Engineering Xi’an University of Posts and TelecommunicationsXi'an 710121China

We proposed and demonstrated a new scheme for simultaneous generation of independent wired and wireless signals employing an integrated polarization multiplexing modulator. In the experimental system, a 10 Gb/s wired signal is imposed on the original optical carrier with one polarization, while a wireless signal with a bit rate larger than 4 Gb/s is carried on the generated millimeter wave of 76.44 GHz, which has polarization orthogonal to the wired signal. The dual services are successfully delivered over a 15 km standard single mode fiber;the power penalties of the wired and wireless signals are around 0.4 d B and 1.5 dB, respectively.

关键词： millimeter wave dual-parallel Mach-Zehnder modulator radio-over-fiber

Regulation of photophysical and electronic properties of I-III-VI quantum dots for light-emitting diodes

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Science China Materials 2024年第9期67卷 2737-2748页

作者： Xiaofei Dong Xianggao li Shougen Yin Zheng li Longwu li jingling li School of Science Langfang Normal UniversityLangfang 065000China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Institute of Material Physics Key Laboratory for Optoelectronic Materials and Devices of TianjinKey Laboratory of Display Materials and Photoelectric Devices of Ministry of EducationTianjin University of TechnologyTianjin 300384China College of Chemistry and Materials Science Langfang Normal UniversityLangfang 065000China School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China

Quantum dot light-emitting diodes(QLEDs)have become an important research direction in the pursuit of next-generation display technology owing to their favorable attributes,including high energy efficiency,wide color gamut,and low *** in the luminous efficiency and operating life of QLEDs have been achieved by enhancing the photoluminescence efficiency of the quantum dots(QDs)and optimizing the device ***,the current mainstream QDs contain heavy metal elements such as lead and cadmium,which restrict the development and application of QD *** new types of environmentally friendly QDs is crucial.I-III-VI semiconductor QDs have been developed as luminescent materials for constructing high color rendering index QLEDs,owing to the outstanding photophysical properties of these QDs,such as composition-dependent tunable bandgap,large Stokes shift,and highefficiency ***,the microstructures of heterojunctions,especially the surface states and interface states,affect the recombination and transport of carriers in electroluminescent(EL)devices with multilayer thin film structures,which in turn influence the luminous efficiency and stability of the *** review focuses on the synthesis strategies of I-III-VI multi-component QDs and provides an in-depth understanding of the luminescence mechanism and the regulation of photophysical and electronic ***,the application of I-III-VI QDs in multi-color and white EL QLEDs is discussed and the challenges and outlook are addressed.

关键词： Ⅰ-Ⅲ-Ⅵquantum dots synthesis method defect states luminescence mechanism light-emitting diodes

Research on Water Sensitivity and Velocity Sensitivity of Loose Sandstone Reservoir in China Offshore Oilfield

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World Journal of Engineering and Technology 2022年第2期10卷 254-263页

作者： Dengfei Yu Ming Long Yuejie Wang Qin Huang jingling li Tianjin Branch of CNOOC Ltd. Tianjin China

Aiming at the development characteristics of Bohai P oilfield, formation mechanism of reservoir damage was analyzed by mines of mineral composition, micro-pore structure, and seepage mechanism. Microscopic petrological observations and laboratory core experiments show that the content of clay minerals such as the Imon mixed layer and kaolinite is high with high porosity and good pore roar structure;the water sensitivity is medium to strong, The lower the salinity of injected water, the greater the drop in core permeability;the velocity-sensitive damage is strong, and permeability increases with the increase in flow velocity, and a large number of particles are observed in the produced fluid under the microscope. Aiming at the contradiction of velocity sensitivity between core permeability increase and the permeability decrease near the wellbore, the velocity sensitivity seepage model of “long-distance migration and blockage near the well” is proposed, and the permeability and formation distribution formula are deduced. The calculated value is close to the test value of actual pressure recovery test. The research results of water sensitivity and velocity sensitivity provide important guidance for Bohai P oilfield to improve production and absorption capacity and reservoir protection.

关键词： Reservoir Damage Water Sensitivity Velocity Sensitivity Loose Sandstone Seepage Mechanism Clay Minerals

四大产区莼菜黄酮类物质组成分析及抗氧化、抑菌活性研究

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食品与发酵工业 2021年第1期47卷 236-242页

作者：韩芳李京凌袁婧于杰西南大学园艺园林学院重庆400715 南方山地园艺学教育部重点实验室重庆400715

为研究莼菜黄酮类物质组成及抗氧化、抑菌体外功能活性,利用紫外-可见分光光度法和高效液相色谱法分别测定中国四大产区莼菜总黄酮、黄酮类物质组成及含量,2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸(2,2'-azino-bis(3-ethylbenzothiazoline... 详细信息

为研究莼菜黄酮类物质组成及抗氧化、抑菌体外功能活性,利用紫外-可见分光光度法和高效液相色谱法分别测定中国四大产区莼菜总黄酮、黄酮类物质组成及含量,2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS),1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH),铁还原/抗氧化能力(ferric reducing/antioxidant power,FRAP)三种抗氧化法评价各产区莼菜黄酮抗氧化能力,滤纸片扩散法测定莼菜黄酮对变形杆菌(Proteus vulgaris)、大肠杆菌(Escherichia coli)和铜绿假单胞菌(Pseudomonas aeruginosa)的抑菌效果。结果显示:石柱莼菜总黄酮含量最高,为(42. 505±0. 458) mg/g,西湖莼菜最低,为(15. 845±0. 119) mg/g;供试材料中共检测到7种黄酮类物质,主要为异鼠李素、槲皮素和山奈酚3种;各产区莼菜均具有较好的抗氧化活性及不同程度的抑菌活性,且其大小变化顺序一致,均为:石柱莼菜﹥利川莼菜﹥雷波莼菜﹥西湖莼菜。该结果为莼菜黄酮类物质的进一步研究提供参考。

关键词：莼菜黄酮类抗氧化抑菌高效液相色谱

内毒素血症对大鼠肾功能及肾素-血管紧张素系统的影响分析

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中国比较医学杂志 2021年第9期31卷 72-77页

作者：李晶铃阴赪宏清华大学医院内科北京100086 北京妇产医院北京100026

目的探讨内毒素血症大鼠不同阶段肾功能和肾素-血管紧张素(RAS)系统的变化,为完善其病理机制提供数据支持。方法将90只大鼠随机分为9组:对照组(n=10)和模型组的8个时间点(注射后2、4、8、12、24、48、72、168 h组,n=10)。模型组采用腹... 详细信息

目的探讨内毒素血症大鼠不同阶段肾功能和肾素-血管紧张素(RAS)系统的变化,为完善其病理机制提供数据支持。方法将90只大鼠随机分为9组:对照组(n=10)和模型组的8个时间点(注射后2、4、8、12、24、48、72、168 h组,n=10)。模型组采用腹腔注射LPS的方式制备脓毒症模型,对照组注射等体积的无热源水。对照组于注射后8 h,模型组于各个时间点取心脏血,测定循环内毒素、一氧化氮(NO)、内皮素(ET)、一氧化氮合酶(NOS)、肾素(PRA)、血管紧张素转换酶(ACE)、血管紧张素(Ang)、血肌酐和尿素氮水平。取肾组织,测定血管紧张素1型受体(AT1R)和2型受体(AT2R)的蛋白表达。结果在LPS注射后,模型组循环内毒素、ET、NO、NOS、PRA、ACEⅡ、AngⅠ、AngⅡ、血肌酐、尿素氮,肾组织AT1R和AT2R表达均有不同程度的升高,其中肾脏系数、血清内毒素、血肌酐、尿素氮、肾组织AT1R和AT2R表达在注射后2~168 h的水平高于对照组,血清内皮素、NOS、AngⅡ在注射2~48 h高于对照组,NO在注射4~48 h高于对照组,ACE在2~24 h高于对照组,差异有统计学意义(P<0.05)。结论内毒素血症所致肾损伤中可能有RAS的参与。

关键词：内毒素血症肾素-血管紧张素系统肾氧化应激损伤

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卫星融合交换系统负载均衡异构路径算法

中国空间科学技术 2021年第3期41卷 105-113页

作者：李静玲黎军张怡崔涛梁薇中国空间技术研究院西安分院空间微波技术重点实验室西安710100

卫星交换系统中的光与分组两种异构业务需要进行融合交换,为了合理利用卫星异构交换系统中的异构路径资源,需要对异构交换路径采用一体化生成方法。基于卫星异构融合交换结构模型,定义了异构路径影响因子,用以定量衡量异构路径对整体交... 详细信息

卫星交换系统中的光与分组两种异构业务需要进行融合交换,为了合理利用卫星异构交换系统中的异构路径资源,需要对异构交换路径采用一体化生成方法。基于卫星异构融合交换结构模型,定义了异构路径影响因子,用以定量衡量异构路径对整体交换性能的影响,并针对卫星交换结构特点,采用交换系统子路径个数以及路径转换参数作为约束条件,通过构建异构路径资源权值函数,准确评估卫星异构交换系统中路径的负载均衡能力。研究了在异构交换系统中采用不同算法对于网络负载均衡度和路径拥塞概率指标的影响,仿真结果表明,与传统路由与波长分配算法相比,该算法可以在特定网络业务负载下将系统平均负载平衡度降低约32%,平均路径阻塞概率降低约51%。

关键词：卫星网络融合交换光、分组异构路径路径算法负载均衡