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Effect of copper on phospholipid fatty acid composition of microbial communities in two red soils

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Journal of Environmental Sciences 2006年第3期18卷 503-509页

作者： YAO Huai-ying LIU Yue-yan xue dong HUANG Chang-yong Institute of Soil and Water Resources and Environmental Science Zhejiang University Hangzhou 310029 China

The phospholipid fatty acid （PLFA） composition was analyzed in two red soils experimentally contaminated with copper at different concentrations. The total amounts ofphospholipid fatty acids （PLFAs） in both red soils were significantly correlated with soil microbial biomass C and N, which decreased consistently with increasing levels of copper. The relative quantities of the PLFAs 17：0 （10 Me）, i16：0, il 5：0 and 16：1w5c, decreased with increasing heavy metal concentration, while those of cyl7：0, which is an indicator of gram-negative bacteria, increased. The Shannon index calculated from the PLFA data indicated that Cu addition in the red soils decreased the population diversity of soil microbial communities. Multivariate analysis of PLFA data demonstrated that high levels of Cu application had a significant impact on microbial community structure and there is a threshold metal concentration for PLFA composition. Comparatively higher toxic effect on microbial biomass and community structure were found in the red sandy soil than those in the red clayey soil. The differential effect of Cu addition on microbial communities in the two soils may be due to differences in soil texture and cation exchange capacity.

关键词： copper phospholipid fatty acid microbial biomass red soil

Landfill leachate production, quality and recirculation treatment in northeast China

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Journal of Environmental Sciences 2006年第4期18卷 625-628页

作者： ZHAO Qing-liang LIU xue-yan QI Xu-dong LIU Zhi-gang School of Municipal and Environment Engineering Harbin Institute of Technology Harbin 150090 China

Landfill leachate recirculation treatment process is a promising and economic way in northeast China due to the distinct season variation. In order to study the impact of recirculation on leachate production and its quality, two simulated sanitary landfill reactors, one with leachate recirculation and the other without, were placed outdoor in Harbin. The two-year experimental results indicated that leachate production was reduced by 86% with leachate recirculation and less or no facility for leachate treatment required. Recirculation could improve the leachate quality dramatically with lower COD, SS, NF4-N and higher pH level. Recirculation also could enhance waste degradation and stabilization and improve the efficiency of landfill. This study confirmed that leachate recirculation was a very feasible way for on-site landfill leachate treatment in cold areas.

关键词： cold area sanitary landfill leachate recirculation solid waste

All-fiberized very-large-mode-area Yb-doped fiber based high-peak-power narrow-linewidth nanosecond amplifier with tunable pulse width and repetition rate

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Chinese Physics B 2020年第11期29卷 343-349页

作者： Min yang Ping-xue Li dong-Sheng Wang Ke-Xin Yu xue-yan dong Ting-Ting Wang Chuan-Fei Yao Wei-Xin yang Institute of Laser Engineering Beijing University of TechnologyBeijing 100124China

We demonstrate an all-fiberized narrow-linewidth nanosecond amplifier with high peak power,tunable pulse width,and repetition rate.A fiber-coupled narrow-linewidth laser diode operating at 1064.1 nm is employed as the seed source,which is gain-switched to generate nanosecond pulses with tunable pulse widths of 1-200 ns and tunable repetition rates of10 Hz-100 *** utilizing a very-large-mode-area Yb-doped fiber with a core diameter of 50 μm in the power amplifier,thresholds of the stimulated Brillouin scattering at different pulse widths and repetition rates are *** maximum average power reaches 30.8 W at the pulse width of 4 ns and a repetition rate of 100 kHz,corresponding to an optical-tooptical conversion efficiency of ~55.2%.Pulse energy and peak power are calculated to be 0.2 mJ and 50 kW,respectively,which are limited by stimulated Brillouin *** 3-dB spectral linewidth remains around 0.05 nm during the power scaling *** stimulated Brillouin scattering limited output powers at different pulse widths and repetition rates are *** power of 47.5 kW(0.19 mJ) is obtained for the 4 ns pulses at a repetition rate of 50 kHz,which is nearly the same as that of 4 ns pulses at 100 *** the pulse width of the seed source is increased to 8 ns,peak powers/pulse energies are decreased to 19.6 kW/0.11 mJ and 13.3 kW/0.08 mJ at repetition rates of 50 kHz and 100 kHz,respectively.

关键词： nanosecond all-fiber amplifier very-large mode area tunable pulse width and repetition rate

The 266-nm ultraviolet-beam generation of all-fiberized super-large-mode-area narrow-linewidth nanosecond amplifier with tunable pulse width and repetition rate

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Chinese Physics B 2022年第3期31卷 292-298页

作者： Shun Li Ping-xue Li Min yang Ke-Xin Yu Yun-Chen Zhu xue-yan dong Chuan-Fei Yao Institute of Ultrashort Pulsed Laser and Application Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

We report on a compact, stable, all-fiberized narrow-linewidth(0.045 nm) pulsed laser source emitting laser beam with a wavelength of 266 nm, and tunable pulse width and repetition rate. The system is based on all-fiberized nanosecond amplifier architecture, which consists of Yb-doped fiber preamplifiers and a super-large-mode-area Yb-doped fiber power amplifier. The fiber amplifier with a core of 50 μm is used to raise the threshold of the stimulated Brillouin scattering(SBS) effect and to obtain high output power and single pulse energy. Using lithium triborate(LBO) crystal and betabarium borate(BBO) crystal for realizing the second-harmonic generation(SHG) and fourth-harmonic generation(FHG),we achieve 17 μJ(1.73 W) and 0.66 μJ(66 mW), respectively, at wavelengths of 532 nm and 266 nm and a repetition rate of 100 kHz with pulse width of 4 ns. This source has great potential applications in fluorescence research and solar-blind ultraviolet optical communication.

关键词： nanosecond all-fiber amplifier narrow-linewidth ultraviolet beam generation tunable pulse width and repetition rate

Characteristics and Driven Factors of Nitrous Oxide and Carbon Dioxide Emissions in Soil Irrigated with Treated Wastewater

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Journal of Integrative Agriculture 2012年第8期11卷 1354-1364页

作者： xue yan-dong yanG Pei-ling LUO Yuan-pei LI Yun-kai REN Shu-mei SU yan-ping NIU Yong-tao College of Water Resources and Civil Engineering China Agricultural University Beijing 100083 P.R.China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

The reuse of treated wastewater in agricultural systems could partially help alleviate water resource shortages in developing countries. Treated wastewater differs from fresh water in that it has higher concentrations of salts, Escherichia coli and presence of dissolved organic matter, and inorganic N after secondary treatment, among others. Its application could thus cause environmental consequences such as soil salinization, ammonia volatilization, and greenhouse gas emissions. In an incubation experiment, we evaluated the characteristics and effects of water-filled pore space （WFPS） and N input on the emissions of nitrous oxide （N2O） and carbon dioxide （CO2） from silt loam soil receiving treated wastewater. Irrigation with treated wastewater （vs. distilled water） significantly increased cumulative N2O emission in soil （117.97 μg N kg-1）. Cumulative N2O emissions showed an exponentially increase with the increasing WFPS in unamended soil, but the maximum occurred in the added urea soil incubated at 60% WFPS. N2O emissions caused by irrigation with treated wastewater combined with urea-N fertilization did not simply add linearly, but significant interaction （P〈0.05） caused lower emissions than the production of N2O from the cumulative effects of treated wastewater and fertilizer N. Moreover, a significant impact on cumulative CO2 emission was measured in soil irrigated with treated wastewater. When treated wastewater was applied, there was significant interaction between WFPS and N input on N2O emission. Hence, our results indicated that irrigation with treated wastewater should cause great concern for increasing global warming potential due to enhanced emission of N2O and CO2.

关键词： treated wastewater nitrous oxide carbon dioxide water-filled pore space urea

A New Tin Graphite Intercalation Compound for Lithium Ion Batteries

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Chemical Research in Chinese Universities 2006年第5期22卷 639-642页

作者： XIE Hai-ming yan xue-dong YU Hai-ying ZHANG Ling-yun yanG Gui-ling XU yang WANG Rong-shun Department of Chemistry Northeast Normal University Changchun 130024 P. R. China Department of Chemistry Inner Mongolia University for NationalitiesTongliao 028043 P. R. China

A new composite material was fabricated by intercalating tin nanoparticles into graphite. The tin graphite intercalation compound（Sn-GIC） was prepared by the interactions of tin tetrachloride with KC8 （K-GIC） in tetrahydrofuran （THF）. As the anode of lithium ion batteries, Sn-GIC presents a steady reversible capacity（363 mA·h/g） and a good cycling performance in comparison with Sn and SnO2, it suggests that the association of tin with graphite not only improves the reversible capacities, but also prevents the volume changes resulted from lithium insertion and extraction with tin during a charge-discharge process.

关键词： Lithium ion battery Anode material Sn-GIC

Change of soil productivity in three different soils after long-term field fertilization treatments

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Journal of Integrative Agriculture 2020年第3期19卷 848-858页

作者： LIU Kai-lou HAN Tian-fu HUANG Jing ZHANG Shui-qing GAO Hong-jun ZHANG Lu Asad Shah HUANG Shao-min ZHU Ping GAO Su-duan MA Chang-bao xue yan-dong ZHANG Huimin National Engineering Laboratory for Improving Quality of Arable Land/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China National Engineering and Technology Research Center for Red Soil Improvement/Jiangxi Institute of Red Soil Nanchang 331717P.R.China Institute of Plant Nutrition and Environmental Resources Science Henan Academy of Agricultural SciencesZhengzhou 450002P.R.China Institute of Agricultural Resource and Environment Jilin Academy of Agricultural SciencesChangchun 130033P.R.China San Joaquin Valley Agricultural Sciences Center USDA Agricultural Research ServiceCA 93648-9757USA Cultivated Land Quality Monitoring and Protection Center Ministry of of Agriculture and Rural AffairsBeijing 100125P.R.China

Soil productivity(SP) without external fertilization influence is an important indicator for the capacity of a soil to support crop ***,there have been difficulties in estimating values of SPs for soils after various long-term field treatments because the treatment without external fertilization is used but is depleted in soil nutrients,leading to erroneous *** objectives of this study were to estimate the change of SP across different cropping seasons using pot experiments,and to evaluate the steady SP value(which is defined by the basal contribution of soil itself to crop yield) after various longterm fertilization treatments in soils at different geographical *** pot experiments were conducted in Jinxian of Jiangxi Province with paddy soil,Zhengzhou of Henan Province with fluvo-aquic soil,and Gongzhuling of Jilin Province with black soils,*** were collected after long-term field fertilization treatments of no fertilizer(control;CK-F),chemical fertilizer(NPK-F),and combined chemical fertilizer with manure(NPKM-F).The soils received either no fertilizer(F0) or chemical fertilizer(F1) for 3-6 cropping seasons in pots,which include CK-P(control;no fertilizer from long-term field experiments for pot experiments),NPK-P(chemical fertilizer from long-term field experiments for pot experiments),and NPKM-P(combined chemical and organic fertilizers from long-term field experiments for pot experiments).The yield data were used to calculate SP *** initial SP values were high,but decreased rapidly until a relatively steady SP was achieved at or after about three cropping seasons for paddy and fluvo-aquic *** steady SP values in the third cropping season from CK-P,NPK-P,and NPKM-P treatments were 37.7,44.1,and 50.0% in the paddy soil,34.2,38.1,and 50.0% in the fluvo-aquic soil,with the highest value observed in the NPKM-P treatment for all ***,further research is required in the black soils to incorporate more than t

关键词： manure incorporation C/N ratio soil types grain yield

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黄钟之宫的演变与三寸九分之学理基础

中国音乐 2019年第2期 146-153页

作者：薛冬艳西安体育学院艺术系

本文针对《吕氏春秋·仲夏纪·古乐》中对于黄钟之宫、三寸九分的历代评述,梳理了黄钟之宫自先秦至唐宋以降名称及意义的演变,并借助数学史的成果来为三分损益法、三寸九分管予以定位,证明其与度量衡公式之间的关联。厘清黄钟之宫与黄... 详细信息

本文针对《吕氏春秋·仲夏纪·古乐》中对于黄钟之宫、三寸九分的历代评述,梳理了黄钟之宫自先秦至唐宋以降名称及意义的演变,并借助数学史的成果来为三分损益法、三寸九分管予以定位,证明其与度量衡公式之间的关联。厘清黄钟之宫与黄钟律两者的差别,阐释三寸九分含少管与九寸黄钟律管之间不同的学理基础,并阐发宋明出现的阴阳双宫现象其内在的旋宫原理。

关键词：黄钟之宫三寸九分阴阳双宫

基于多用户驾驶模拟平台的雾天高速公路跟驰模型参数标定及验证

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中国公路学报 2022年第8期35卷 320-330页

作者：黄岩闫学东李晓梦熊邦凯北京交通大学综合交通运输大数据应用技术交通运输行业重点实验室北京100044 昆士兰科技大学昆士兰州道路安全与事故研究中心昆士兰开尔文格罗夫QLD4059

高速公路连环追尾事故多发生在雾天环境下,且容易造成严重的事故人员伤亡。当前的跟驰及追尾风险研究多集中于两车跟驰,缺乏对雾天情况下车队跟驰的研究。利用雾天环境下车队跟驰轨迹数据对传统主流跟驰模型进行标定验证,基于多用户驾... 详细信息

高速公路连环追尾事故多发生在雾天环境下,且容易造成严重的事故人员伤亡。当前的跟驰及追尾风险研究多集中于两车跟驰,缺乏对雾天情况下车队跟驰的研究。利用雾天环境下车队跟驰轨迹数据对传统主流跟驰模型进行标定验证,基于多用户驾驶模拟平台设计了8个不同雾天等级和限速组合的高速公路虚拟场景,开展驾驶模拟试验并采集数据。试验招募了8名男性驾驶人并通过随机调整他们在车队中的位置顺序来获得足够的车队跟驰轨迹数据,根据判定标准筛选合适的车队跟驰轨迹数据,按照2∶1的原则分配标定和验证阶段的数据组。选取Newell、Gipps和IDM三个主流跟车模型进行参数标定和验证,以时间序列的车头间距和相对均方根误差(RMSPE)分别作为性能指标参数和拟合优度函数,使用遗传算法搜寻目标函数最小值以标定跟驰模型参数,并用车辆轨迹完整性(CVT)和RMSPE评价验证阶段的仿真结果。结果表明:在标定阶段,Newell、Gipps和IDM三个模型的RMSPE整体平均值分别为30.1%、18.6%和27.7%,各个试验条件下Gipps模型的RMSPE值均小于另外2个模型,说明Gipps模型能更好地拟合试验数据;在验证阶段,Gipps模型的RMSPE整体平均值为21.2%,远小于另外2个模型,可见Gipps模型在局部精确度上的鲁棒性要优于Newell模型和IDM模型;Gipps模型的CVT整体平均值和波动幅度分别为98.1%和2.0%,均是3个模型中的最小值,说明Gipps模型在整体轨迹上的鲁棒性也优于另外2个模型。雾天环境下,Gipps模型具备更好的拟合能力和鲁棒性,因此推荐仿真软件使用Gipps模型模拟雾天环境下车队跟驰行为,不同雾天等级及限速下的Gipps模型参数可参考该研究标定的参数。

关键词：交通工程参数标定及验证多用户驾驶模拟平台跟驰模型雾天高速公路