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Variation Characteristics of Root Traits of Different Alfalfa Cultivars under Saline-Alkaline Stress and their Relationship with Soil Environmental factors

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 29-43页

作者： Tian-Jiao Wei Guang Li Yan-Ru Cui Jiao Xie xing-Ai Gao xing Teng xin-Ying Zhao fa-Chun Guan Zheng-Wei Liang Northeast Agricultural Research Center of China Jilin Academy of Agricultural SciencesChangchun130033China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130102China

Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of *** is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil *** this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment *** the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried *** results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline *** was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline *** number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control *** ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(pfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase ac

关键词： Saline-alkaline stress alfalfa root traits soil environmental factors correlation analysis

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Characteristics and origin of low-organicmatter carbonate source rocks in the Middle-Upper Ordovician, Tarim Basin, northwestern China

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Journal of Palaeogeography 2024年第3期13卷 594-619页

作者： Jun-Qing Chen Fu-Jie Jiang Xiong-Qi Pang Hai-Jun Yang Kan-Yuan Shi Bo Pang Hong Pang Jian-fa Chen Zhuo-Heng Chen xin-Gang Zhang Song Wu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China Basic Research Center for Energy Interdisciplinary College of ScienceChina University of Petroleum(Beijing)Beijing 102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration and Development PetroChina Tarim Oilfield CompanyKorla 841000Xinjiang Uygur Autonomous RegionChina Geological Survey of Canada Natural Resources CanadaCalgary T2L 2A7Canada

The continually-discovered large volumes of marine hydrocarbons indicate a huge exploration potential within the carbonate rocks of Ordovician in the Tarim Basin,northwestern *** Middle-Upper Ordovician(O2+3)carbonate source rocks are at a highly mature *** rocks presently contain a low amount of total organic carbon(TOC_(pd)≤0.5%)(TOC_(pd) means the present-day TOC).A mass balance approach is used to identify the source rocks that have expelled *** characteristics and origin of hydrocarbon expulsion from low-TOC_(pd) source rocks are studied,which are significant for oil exploration in the *** results showed that a low-TOC_(pd) O2+3 source rock having expelled hydrocarbons was type I and had a very narrow oil *** a high rock maturity and a high original TOC(TOCo)value exceeding 1%,nearly 80%of the generated hydrocarbons were *** content of gammacerane and C28 steranes in the oil and source rock extracts were relatively lean,with a V-shaped distribution of regular steranes,suggesting a possible genetic relation between the low-TOC_(pd) source rocks and the marine oil in the Tabei *** planktonic algae or acritarchs were the main hydrocarbon parent materials,distributed in the subsiding platform-slope *** matter was preserved under reducing conditions,and source rocks were formed with a favorable kerogen type and a moderate hydrocarbon generation *** study illustrates the hydrocarbon expulsion of low TOC_(pd) source rocks in northern Tarim Basin,which is greatly significant for analyzing the genesis of marine crude oil in Tarim Basin,and evaluating the distribution of marine source *** research method is theoretically significant for oil and gas exploration in the same type of highlymature carbonate paleobasins.

关键词： Carbonate source rock Mass balance approach Present-day TOC Genesis mechanism Tarim Basin

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Heavy neutral leptons in gauged U(1)Lμ-Lτ at muon collider

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Chinese Physics C 2024年第9期48卷 36-49页

作者： Ru-Yi He Jia-Qi Huang Jin-Yuan Xu fa-xin Yang Zhi-Long Han Feng-Lan Shao School of Physics and Technology University of JinanJinan 250022China School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China

Heavy neutral leptons N are the most appealing candidates to generate tiny neutrino *** studied the signature of heavy neutral leptons in gauged U(1)Lμ-Lτ at a muon *** under the U(1)Lμ-Lτ symmetry,the heavy neutral leptons can be pair produced via the new gauge boson Z' at the muon collider as μ^(+)μ^(-)→Z′*→NN AND μ^(+)μ^(-)→Z′(*)γ→NNγ.We then performed a detailed analysis on the lepton number violation signature μ^(+)μ^(-)→NN→μ^(±)μ^(±)W■W■ and μ^(+)μ^(-)→NN→μ^(±)μ^(±)W■W■γ at the 3 TeV muon collider,where the hadronic decays of W boson are treated as fat-jets *** lepton number violation signatures have quite clean backgrounds at the muon *** simulation shows that a wide range of viable parameter space is within the reach of the 3 TeV muon *** instance,with new gauge coupling g'=0.6 and an integrated luminosity of 1000 fb^(-1),the μ^(±)μ^(±)JJ signal could probe m_(Z′)■13 ***,if the gauge boson mass satisfies 2m_(N)<√s,the μ^(±)μ^(±)JJγ signature would be more promising than the μ^(±)μ^(±)JJ signature.

关键词： heavy neutral leptons gauged U(1)_(Lμ-Lτ) muon collider lepton number violation

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High-Performance and Large-Area Inverted Perovskite Solar Cells Based on NiO_(x) Films Enabled with A Novel Microstructure-Control Technology

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Energy & Environmental Materials 2024年第1期7卷 153-159页

作者： Guibin Shen xin Li Yuqin Zou Hongye Dong Dongping Zhu Yanglin Jiang xin Ren Ng Fen Lin Peter Müller-Buschbaum Cheng Mu Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of ChemistryRenmin University of ChinaBeijing 100872China Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore Physik-Department Lehrstuhl für Funktionelle MaterialienTechnische Universität MünchenJames-Franck-Straße 185748Garching Germany Heinz Maier-Leibnitz Zentrum(MLZ) Technische Universität MünchenLichtenbergstr.185748Garching Germany

The improvement in the efficiency of inverted perovskite solar cells(PSCs)is significantly limited by undesirable contact at the NiO_(x)/perovskite *** this study,a novel microstructure-control technology is proposed for fabrication of porous NiO_(x)films using Pluronic P123 as the structure-directing agent and acetylacetone(AcAc)as the coordination *** synthesized porous NiO_(x)films enhanced the hole extraction efficiency and reduced recombination defects at the NiO_(x)/perovskite ***,without any modification,the power conversion efficiency(PCE)of the PSC with MAPbl_(3)as the absorber layer improved from 16.50%to 19.08%.Moreover,the PCE of the device composed of perovskite Cs0.05(MA_(0.15)fa_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))_(3)improved from 17.49%to 21.42%.Furthermore,the application of the fabricated porous NiO_(x)on fluorine-doped tin oxide(FTO)substrates enabled the fabrication of large-area PSCs(1.2 cm^(2))with a PCE of 19.63%.This study provides a novel strategy for improving the contact at the NiO_(x)/perovskite interface for the fabrication of high-performance large-area perovskite solar cells.

关键词： interfacial contact inverted and large-area perovskite solar cells photovoltaic materials porous NiO_(x)films renewable energy

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A review of vortex pinning in REBa_(2)Cu_(3)O_(7-x) coated conductors

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cMat 2024年第1期1卷 110-125页

作者： Tong-xin Wang Da-xing Huang fa-Zhu Ding Hao Dong Hao Yu Chao-Chao dun Hong-Wei Gu Key Laboratory of Applied Superconductivity and Institute of Electrical Engineering Chinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina The Molecular Foundry Lawrence Berkeley National Laboratory BerkeleyBerkeleyCaliforniaUSA

REBa_(2)Cu_(3)O_(7-x)exhibits outstanding qualities such as a high irreversible field(7 T)and strong current-carrying capacity(77 K,10^(6) A cm^(-2)),making it ideal for high magnetic field applications such as fusion,accelerators,and nuclear magnetic ***,the degradation of in-field critical current density(Jc)due to vortex motion is a significant *** indicates that improving vortex pinning can notably enhance Jc in REBCO,showing promise for its future high-field *** review explores vortex pinning mecha-nisms,artificial pinning centers(APCs),and how environmental conditions affect pinning characteristics,highlighting advancements in vortex pinning for REBCO in magnetic *** methods for introducing APCs are discussed and compared for evaluating their efficacy in achieving optimal nanoparticle distri-butions and consequent superconducting performance improvements,under-scoring the importance of nano-defect features(type,size,and distribution)in optimizing the superconducting properties of the ***,the re-view tackles current challenges,shares recent research breakthroughs,and out-lines future research directions for designing pinning landscapes to further improve REBCO performance.

关键词： critical current density magnetic field REBCO vortex pinning

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撤县设区对县域公共服务供给水平的影响研究——基于江苏省县级面板数据的实证分析

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城市问题 2024年第1期 65-74页

作者：徐发新李雪伟中国人民大学公共管理学院北京体育大学管理学院

基于江苏省2006—2020年的县域面板数据,使用多期双重差分法考察了撤县设区改革对县域政府公共服务供给水平的影响。结果显示,撤县设区改革提升了交通基础设施等经济性公共服务供给水平,对教育和医疗等民生性公共服务供给水平则带来了... 详细信息

基于江苏省2006—2020年的县域面板数据,使用多期双重差分法考察了撤县设区改革对县域政府公共服务供给水平的影响。结果显示,撤县设区改革提升了交通基础设施等经济性公共服务供给水平,对教育和医疗等民生性公共服务供给水平则带来了负面影响。分样本回归结果显示,撤县设区改革在不同经济发展水平地区的政策效应存在显著差异。总体而言,“重经济而轻民生”的问题仍然存在,尤其在中低发展水平地区更为明显。机制分析结果显示,撤县设区改革促进了中低发展水平地区的人口增长,但公共服务供给的增长不及人口规模的增长,从而导致了“拥挤效应”。因此,是否实行撤县设区改革需要因地制宜,综合考量。而已经实行改革的地区则应转变政府职能,优化资源配置,以服务型政府建设推动公共服务供给水平提升,确保经济与民生同步发展。

关键词：撤县设区改革公共服务供给水平县域发展双重差分法

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模糊性政策执行模式的动态转换逻辑——以异地就医即时结算政策为例

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中国卫生政策研究 2024年第4期17卷 1-7页

作者：徐发新李雪伟中国人民大学公共管理学院北京100872 北京体育大学管理学院北京100084

目的:在高度复杂性和不确定性条件下,模糊性日益成为公共政策的显要属性。缘于模糊性,政策执行过程往往伴随执行模式的动态转换,而学界对该转换过程和机制缺乏足够探讨。方法:本研究基于修正的模糊—冲突模型和多源流模型,构建了一个解... 详细信息

目的:在高度复杂性和不确定性条件下,模糊性日益成为公共政策的显要属性。缘于模糊性,政策执行过程往往伴随执行模式的动态转换,而学界对该转换过程和机制缺乏足够探讨。方法:本研究基于修正的模糊—冲突模型和多源流模型,构建了一个解释模糊性政策执行模式动态转换的分析框架,并以异地就医即时结算政策为例对模式转换逻辑进行了阐释。结果:同一项模糊性政策在执行中会经历从试验性执行到象征性执行,再到政治性执行,最终进入常态化行政性执行的动态转换过程。促使执行模式转换的原因与对应阶段的主导动力源流密不可分。结论与建议:细化的执行手段、清晰的权责关系、自上而下的高位推动、充足的执行资源及数字化技术都有助于降低政策的模糊性和冲突性,提升政策执行效果。

关键词：模糊性政策政策执行模糊—冲突模型多源流模型执行模式转换

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A folic acid-decorated nanoparticles loaded JQ1 for oral squamous cell carcinoma therapy

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Chinese Chemical Letters 2024年第3期35卷 332-336页

作者： Dequan Zeng Zhongkai Ma xin Zan Ting Luo Xiang Wang Xiang Gao Xianghui Fu School of Health Management Xihua UniversityChengdu 610039China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China College of StomatologySichuan UniversityChengdu 610041China Department of Neurosurgery and Institute of Neurosurgery State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalWest China Medical SchoolSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China Breast Disease Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China

Oral squamous cell carcinoma(OSCC)is known as one of the most malignant tumors with high recurrence and fatality *** poor tumor-targeting ability of traditional chemotherapeutic drugs has been a grand challenge for anti-OSCC *** that,a large quantity of tumor associated macrophages in OSCC tissues further diminish the anti-tumor effects of these ***,we produced a therapeutic nano drug delivery system(fa-PEG-PLA-JQ1)through encapsulating JQ1[a small-molecule inhibitor of bromodomain containing protein 4(BRD4)]into the folic acid(fa)-modified nanoparticle(PEG-PLA),which could prolong the half-life of JQ1 and target the tumor *** then,JQ1 released from this nanoparticle could prevent OSCC growth inducing tumor cell apoptosis,inhibiting tumor angiogenesis and the polarization of M2 type *** conclusion,our date demonstrated the therapeutic benefits of fa-PEG-PLA-JQ1 against OSCC in vivo or in vitro,which could be a novel treatment strategy for OSCC in coming days.

关键词： Folic acid Nanoparticles JQ1 Oral squamous cell carcinoma Macrophages

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多年度同时相“星-地”协同遥感反演鄱阳湖叶绿素a浓度

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长江科学院院报 2024年第7期41卷 48-56页

作者：郑璞许新发许小华陈鑫雨张任高江西省水利科学院南昌330029 江西省鄱阳湖流域生态水利技术创新中心南昌330029 中国水利水电科学研究院北京100038 东华理工大学测绘工程学院南昌330013

作为长江最大的通江湖泊,鄱阳湖水生态安全影响着整个长江流域。叶绿素a浓度是水生态富营养化的重要指标,利用遥感技术开展叶绿素a浓度常规监测具有重要意义。以鄱阳湖为试验区,以表征富营养化程度的叶绿素a浓度为反演指标,基于2015—2... 详细信息

作为长江最大的通江湖泊,鄱阳湖水生态安全影响着整个长江流域。叶绿素a浓度是水生态富营养化的重要指标,利用遥感技术开展叶绿素a浓度常规监测具有重要意义。以鄱阳湖为试验区,以表征富营养化程度的叶绿素a浓度为反演指标,基于2015—2020年6 a的观测数据以及Landsat系列影像,在规范建模时相以及“星-地”协同匹配的情况下,通过分析对比不同波段与叶绿素a浓度的相关指数,构建了适用于夏季鄱阳湖水体叶绿素a浓度反演模型。经6组独立数据验证后R 2均值为0.86,RMSE均值为1.01μg/L,MAPE均值为17.6%,认为所采用的方法可以较好地适用于鄱阳湖区夏季(丰水期)叶绿素a浓度的的反演,同时也为具备长期观测条件下内陆二类水体叶绿素a浓度监测提供了新的参考方法。

关键词：遥感反演鄱阳湖叶绿素a 相关性分析

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氮添加与凋落物处理对橡胶林砖红壤有机碳组分及酶活性的影响

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环境科学 2024年第1期45卷 354-363页

作者：薛欣欣任常琦罗雪华王文斌赵春梅张永发中国热带农业科学院橡胶研究所海口571101 海南天然橡胶与热带林木研究院海口571101

研究氮添加与凋落物处理对土壤有机碳组分及酶活性的影响对调控人工林生态系统恢复具有重要意义.于海南岛西部橡胶林地开展野外微区模拟试验,采用二因素完全随机设计,设置4个氮水平[不施氮(CK,0 kg·hm^(-2)·a^(-1),以N计,下同),低氮(L... 详细信息

研究氮添加与凋落物处理对土壤有机碳组分及酶活性的影响对调控人工林生态系统恢复具有重要意义.于海南岛西部橡胶林地开展野外微区模拟试验,采用二因素完全随机设计,设置4个氮水平[不施氮(CK,0 kg·hm^(-2)·a^(-1),以N计,下同),低氮(LN,50 kg·hm^(-2)·a^(-1)),中氮(MN,100 kg·hm^(-2)·a^(-1))和高氮(HN,200 kg·hm^(-2)·a^(-1))]以及2种凋落物处理[凋落物去除(LR),凋落物保留(L)],分析0~10 cm和10~20cm土层的土壤理化性质、总有机碳(SOC)及其组分、酶活性等指标.结果表明,土壤pH随N添加量增加以及凋落物的去除呈显著降低的趋势(P<0.05).土壤NO_(3)^(-)-N和NH_(4)^(+)-N含量随N添加的增加显著增加,N添加和凋落物处理对NO_(3)^(-)-N和NH_(4)^(+)-N含量有显著的交互效应.与L处理相比,LR降低了土壤SOC及其各组分含量,其中轻组有机碳(LFOC)含量降幅最大,在0~10 cm和10~20 cm土层降幅分别为29.0%~81.4%和23.5%~58.4%.不同凋落物处理条件下,SOC及其各组分含量随N添加量的增加均呈先增加后降低的趋势,LN处理显著高于HN处理.N添加和凋落物处理对SOC、LFOC(0~10cm)和重组有机碳(HFOC)含量有极显著的交互作用(P<0.01).与L处理相比,LR处理在CK和LN处理条件下的土壤多酚氧化酶(PPO)活性显著降低,而在MN和HN条件下,LR处理的PPO含量显著增加;方差分析显示,N添加和凋落物处理对PPO和0~10 cm土层的纤维素酶(CBH)活性有极显著影响的交互作用,土壤酶活性[β-葡萄糖苷酶(BG)、PPO、CBH]对N添加处理的响应程度均大于对凋落物处理的响应.相关性分析表明,SOC含量与微生物生物量碳(MBC)、颗粒态有机碳(POC)、LFOC以及HFOC含量之间呈极显著正相关关系.总体来看,凋落物保留与低N输入对橡胶林地土壤碳库以及酶活性具有较好的协同作用.

关键词：凋落物氮添加橡胶林有机碳组分酶活性

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