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Study of Dynamics of Floodwater Nitrogen and Regulation of Its Runoff Loss in Paddy Field-Based Two-Cropping Rice with Urea and Controlled Release Nitrogen Fertilizer Application

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Agricultural Sciences in China 2007年第2期6卷 189-199页

作者： JI Xiong-hui ZHENG Sheng-xian luyan-hong LIAO Yu-lin Hunan Provincial Soil ＆ Fertilizer Institute Changsha 410125 P.R.China Hunan Agricultural University Changsha 410128 P.R.China Key Field Monitoring Experimental Station for Reddish Paddy Soil Eco-Environment in Wangcheng Ministry of Agriculture Changsha 410125 P.R.China

The article deals with the effects of urea and controlled release nitrogen fertilizer （CRNF） on dynamics of pH, electronic conductivity （EC）, total nitrogen （TN）, NH4^＋-N and NO3 -N in floodwater, and the regulation of runoff TN loss from paddy field-based two-cropping rice in Dongting Lake, China, and probes the best fertilization management for controlling N loss. Studies were conducted through modeling alluvial sandy loamy paddy soil （ASP） and purple calcareous clayey paddy soil （PCP） using lysimeter, following the sequence of the soil profiles identified by investigating soil profile. After application of urea in paddy field-based two-cropping rice, TN and NHa＋-N concentrations in floodwater reached peak on the 1st and the 3rd day, respectively, and then decreased rapidly over time; all the floodwater NO3--N concentrations were very low; the pH of floodwater gradually rose in case of early rice within 15 d （late rice within 3 d） after application of urea, and EC remained consistent with the dynamics of NH4^＋-N. The applied CRNF, especially 70% CRNF, led to significantly lower floodwater TN and NH4^＋ concentrations, pH, and EC values compared with urea within 15 d after application. The monitoring result for N loss due to natural rainfall runoff indicated that the amount of TN lost in runoff from paddy field- based two-cropping rice with urea application in Dongting Lake area was 7.47 kg ha^-1, which accounted for 2.49% of urea- N applied, and that with CRNF and 70% CRNF application decreased 24.5 and 27.2% compared with urea application, respectively. The two runoff events, which occurred within 20 d after application, contributed significantly to TN loss from paddy field. TN loss due to the two runoffs in urea, CRNF, and 70% CRNF treatments accounted for 72, 70, and 58% of the total TN loss due to runoff over the whole rice growth season, respectively. And the TN loss in these two CRNF treatments due to the first run-off event at the 10th day after application

关键词： controlled release nitrogen fertilizer paddy field-based two-cropping rice floodwater nitrogen loss due to runoff

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Ginsenoside Rg1 and astaxanthin act on the hypothalamus to protect female mice against reproductive aging

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Chinese Medical Journal 2022年第1期135卷 107-109页

作者： Xiaoman Dai Guirong Zeng luyan hong Qinyong Ye Xiaochun Chen Jing Zhang Department of Neurology and Geriatrics Fujian Institute of GeriatricsFujian Medical University Union HospitalFuzhouFujian 350001China Fujian Key Laboratory of Molecular Neurology Institute of NeuroscienceFujian Medical UniversityFuzhouFujian 350005China

To the Editor:Female infertility due to reproductive aging has become a prominent concern in the *** indicates that oxidative stress is one of the dominant mechanisms underlying reproductive aging.[1,2]Although female reproductive aging involves gradual changes to the hypothalamic-pituitary-ovarian(HPO)axis,previous studies support a key involvement of the hypothalamus.[3,4]In our recent dataset,it was shown that estrogen-induced oxidative stress led to the senescence of hypothalamic astrocytes that predated reproductive dysfunction.[3]Growing evidence has demonstrated that antioxidants might delay reproductive aging by reducing oxidative damage to ovaries.[1,2]However,the effect of antioxidants on the hypothalamus has not been ***(AST),3,3'-dihydroxy-β-carotene-4,4'-dione,is a xanthophyll carotenoid found predominantly in marine animals such as salmon,trout,lobster,and *** is a tonic drug in traditional Chinese *** Rg1,a class of steroidal glycosides,is a prominent active anti-aging ingredient within ginseng responsible for these ***,the two antioxidants freely cross the blood-brain *** this study,we evaluated the effects of these two natural compounds on the hypothalamus and ovaries in protecting female mice from reproductive aging.

关键词： hypothalamus female involvement

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机构改革背景下的海关行政处罚权整合探究

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海关与经贸研究 2018年第5期39卷 93-101页

作者：洪燕鹭赵波厦门海关缉私局海关总署统计分析司

2018年3月,十三届全国人大一次会议审议通过了《国务院机构改革方案》,自改革开放以来的第八次国务院机构改革拉开序幕。此次改革中,出入境检验检疫职能和队伍划入海关总署,以期进一步转变优化职能,建设通关效率更高、通关成本更低、监... 详细信息

2018年3月,十三届全国人大一次会议审议通过了《国务院机构改革方案》,自改革开放以来的第八次国务院机构改革拉开序幕。此次改革中,出入境检验检疫职能和队伍划入海关总署,以期进一步转变优化职能,建设通关效率更高、通关成本更低、监管更严密、服务更优化的中国特色社会主义新海关。行政处罚是行政机关给予管理相对人最严厉的行政制裁,也是法律赋予关检系统共有的职权。本文以此次机构改革为背景,以实现海关行政处罚权的统一规范为切入点,旨在为全面推进机构改革和职能整合提供参考。

关键词：海关职能出入境检验检疫行政处罚权整合

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“核酸的结构与功能”的课程思政教学设计与探讨

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生命的化学 2021年第7期41卷 1637-1640页

作者：许春鹃洪芦燕罗晓婷赣南医学院基础医学院生物化学与分子生物学教研室赣州341000

课程思政是将思想道德教育融入课程的一种新的教育形式。教师作为课程思政建设的主力军,其丰富的知识贮备、多元的教学方法以及坚定的理想信念是成功实施课程思政的三大基本要素。本文以生物化学课程中"核酸的结构与功能"的教学为例,从... 详细信息

课程思政是将思想道德教育融入课程的一种新的教育形式。教师作为课程思政建设的主力军,其丰富的知识贮备、多元的教学方法以及坚定的理想信念是成功实施课程思政的三大基本要素。本文以生物化学课程中"核酸的结构与功能"的教学为例,从爱国情感、民族自豪感、法治观念、职业道德和人文素养等方面构建具体的课程思政映射点,介绍了对课程思政融入教学目标、教学设计、教学内容和教学过程的探索,希望为生物化学课程思政建设提供参考。

关键词：核酸课程思政教学设计

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吉林前郭地区一维P波速度模型研究

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防灾减灾学报 2016年第3期32卷 19-24页

作者：张洪艳马铭志刘轶男卢燕红陈聪吉林省地震局吉林长春130117 丰满地震台吉林吉林132000

基于2013年10月31日至2014年8月25日吉林前郭地区发生的290次地震事件的P波到时数据,利用Kissling提出的VELEST程序,获取了前郭地区最小一维P波速度模型。并将新模型应用到前郭地震重定位和PTD定震源深度中,二者综合显示获取的最小一维... 详细信息

基于2013年10月31日至2014年8月25日吉林前郭地区发生的290次地震事件的P波到时数据,利用Kissling提出的VELEST程序,获取了前郭地区最小一维P波速度模型。并将新模型应用到前郭地震重定位和PTD定震源深度中,二者综合显示获取的最小一维P波速度模型对于提高地震定位的精度有一定的现实意义。

关键词：最小一维P波速模型吉林前郭 PTD方法地震重定位

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Spongy acetylenic carbon material prepared by ball milling CaC2 and chlorinated rubber—Its mercury adsorption and electrochemical property

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1988-1995页

作者： Xuebing Xu Wenfeng Li luyan Xia Yingzhou Lu hong Meng Chunxi Li State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

Design and preparation of novel advanced carbon materials with unique architecture and functional groups is of great ***,a spongy acetylenic carbon material(SACM) was prepared through mechanochemical reaction of CaC2 and chlorinated rubber in a planetary ball mill at ambient *** composition and structure were characterized,and its electrochemical properties and adsorption performance for Hg^2+ were *** SACM is composed of submicron spongy aggregates with high carbon content(81.8%) and specific area(503.9 m^2·g^-1),rich porosity and acetylenic *** SACM exhibits excellent adsorption for Hg2+with saturated adsorption amount being 157.1 mg·g^-1,which is superior to conventional carbon ***,it exhibits good electrochemical performance with low equivalent series resistance(0.50 Ω),excellent cycling stability and ideal double layer capacitive *** paper provides a novel and universal synthesis method of spongy carbon materials,and better results can be expected through tuning the pore structure,graphitization degree,and heteroatoms of the target carbon materials.

关键词： Acetylenic carbon material Calcium carbide Mechanochemical reaction Heavy metal adsorption

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Effect of abruptly changing withdrawal rate on solidification microstructure in directionally solidified Al-4.5wt%Cu alloy

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China Foundry 2014年第1期11卷 8-13页

作者： Yang luyan Li Shuangming Zhong hong Ren Ruohua Fu Hengzhi State Key Laboratory of Solidif ication Processing Northwestern Polytechnical University

Al-4.5wt.%Cu alloy has been directionally solidified at constant and abruptly changing withdrawal rates, respectively. The effects of the withdrawal rate on solidification microstructure, primary dendrite arm spacing(PDAS) and liquid solute distribution in front of the solid-liquid interface were investigated. The experimental results for the PDAS at a constant withdrawal rate agree well with the values calculated by the Hunt, Trivedi and Hunt-Lu models. At an abrupt change in the withdrawal rate, the maximum to minimum ratio of the PDAS at a given solidification parameter, i.e. λ1max/λ1min, is more than 2, and the PDAS values are remarkably history-dependent. Further, the liquid-solute distribution curve based on theoretical calculation shows that the larger the initial withdrawal rate is, the smaller the minimum of liquid solute concentration in front of the solid-liquid interface is after the abrupt change in withdrawal rate.

关键词： directional solidification abrupt change of withdrawal rate primary dendrite arm spacing liquid-solute distribution Al-4.5wt.%Cu alloy

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晚稻机收留高茬紫云英迟播技术的应用效果研究

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湖南农业科学 2014年第20期 21-23+27页

作者：鲁艳红廖育林周兴谢坚周升明杨曾平聂军湖南省土壤肥料研究所湖南农业大学资源环境学院长沙市土壤肥料工作站

通过田间试验,研究了双季稻田晚稻机械收获留高茬后紫云英迟播的应用效果。结果表明,与传统紫云英播种技术相比,晚稻机械收获留高茬紫云英迟播显著缩短了紫云英的生育期,但其盛花期能保持与传统播种技术一致,对下茬早稻作物的种植没有影... 详细信息

通过田间试验,研究了双季稻田晚稻机械收获留高茬后紫云英迟播的应用效果。结果表明,与传统紫云英播种技术相比,晚稻机械收获留高茬紫云英迟播显著缩短了紫云英的生育期,但其盛花期能保持与传统播种技术一致,对下茬早稻作物的种植没有影响;两种播种方法对盛花期鲜草产量、植株养分含量和养分积累量均没有显著影响,说明迟播播种能达到与传统播种一样的肥田目的;迟播对紫云英的种子产量及产量构成因素均没有明显影响,与传统播种技术相比可节约劳动力成本约45元/hm2,且可避免传统播种方法对晚稻植株的伤害。在现代双季稻种植条件下,晚稻机械收获留高茬紫云英迟播技术具有较大的优势和发展前景。

关键词：水稻机械收获高茬紫云英迟播技术应用效果

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An activatable ratiometric near-infrared fluorescent probe for hydrogen sulfide imaging in vivo

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Science China Chemistry 2020年第5期63卷 741-750页

作者： luyan Wu Wenhui Zeng Liandong Feng Yuxuan Hu Yidan Sun Yingxiao Yan hong-Yuan Chen Deju Ye State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Chemistry and Biomedicine Innovation Center(ChemBIC) Nanjing UniversityNanjing 210023China

Ratiometric fluorescent probes hold great promise for in vivo imaging;however,stimuli-activatable ratiometric probes with fluorescence emissions in near-infrared(NIR)region are still very ***,we report a hydrogen sulfide(H_2S)-activatable ratiometric NIR fluorescent probe(1-SPN)by integrating a H_2S-responsive NIR fluorescent probe 1 into a H_2S-inert poly[2,6-(4,4-bis-(2-ethylhexyl)-4 H-cyclopenta[2,1-b;3,4-b′]dithiophene)-alt-4,7(2,1,3-benzothiadiazole)](PCPDTBT)-based NIR semiconducting polymer nanoparticle(SPN).1-SPN shows"always on"PCPDTBT fluorescence at 830 nm and weak probe 1 fluorescence at 725 nm under excitation at 680 *** ratio of NIR fluorescence intensities between 725 and 830 nm(I_(725)/I_(830))is *** interaction with H_2S,the fluorescence at 725 nm is rapidly switched on,resulting in a large enhancement of I_(725)/I_(830),which is allowed for sensitive visualization and quantification of H_2S concentrations in living *** advantage of enhanced tissue penetration depth of NIR fluorescence,1-SPN is also applied for real-time ratiometric fluorescence imaging of hepatic and tumor H_2S in living *** study demonstrates that activatable ratiometric NIR fluorescent probes hold great potential for in vivo imaging.

关键词： ratiometric probe activatable probe near-infrared fluorescence molecular imaging H2S

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不同施肥量对桂牧一号产量及氮磷钾吸收的影响

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湖南农业科学 2015年第6期 46-50页

作者：杨曾平聂军廖育林周兴谢坚鲁艳红纪雄辉谢运河湖南省土壤肥料研究所湖南长沙410125 湖南农业大学资源与环境学院湖南长沙410128

为了找到南方稻田种植桂牧一号的适合氮磷肥料配比,以湖南省长沙县金井镇循环农业科技工程基地试验田为平台,通过大田试验,研究不同施肥量对桂牧一号产量及养分吸收的影响。试验设N0P2K、N1P2K、N2P2K、N3P2K、N4P2K、N2P0K、N2P1K、N2... 详细信息

为了找到南方稻田种植桂牧一号的适合氮磷肥料配比,以湖南省长沙县金井镇循环农业科技工程基地试验田为平台,通过大田试验,研究不同施肥量对桂牧一号产量及养分吸收的影响。试验设N0P2K、N1P2K、N2P2K、N3P2K、N4P2K、N2P0K、N2P1K、N2P3K共8个处理。结果表明:基肥施用氮、磷肥尤其是氮肥对桂牧一号有明显增产作用,追施氮肥可以明显促进桂牧一号的再生。桂牧一号基肥施用,氮肥最佳施用量(折纯)为677.5 kg/hm2,磷肥最佳施用量(折纯)为100.4 kg/hm2。氮、磷肥的施用都可以增加桂牧一号氮吸收量,氮肥的作用较磷肥强。氮、磷肥的施用都可以增加桂牧一号的磷吸收量,磷肥的作用较氮肥强。氮、磷肥的施用可以增加桂牧一号的钾吸收量。

关键词：施肥量桂牧一号产量氮磷钾吸收

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