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Journal of Earth Science 2022年第6期33卷 1601-1613页

作者： Xiuchang Zhu Yongbo Wang xinyue dang Huan Yang Shucheng Xie State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430078China School of Earth Sciences China University of GeosciencesWuhan430074China School of Finance and Business Shanghai Normal UniversityShanghai200234China Hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan430078China

Microbial glycerol dialkyl glycerol tetraethers(GDGTs)in lacustrine sediments are widely used to reconstruct terrestrial paleoenvironments.However,lipids of diverse origin in lakes make it difficult to decipher environmental information,appealing for the necessity to evaluate the impact of terrigenous input on the distribution of GDGTs through long-term monitoring.In this study,we conducted two-year monitoring of GDGTs along the river,estuary,near shore,to the center of Lake Liangzi in central China.By comparing the spatiotemporal changes of GDGT distribution in suspended particulate matter(SPM)and surface sediments,we found that the archaeal isoprenoid GDGTs(isoGDGTs)were mainly produced in situ in the river-lake systems,and not affected by the soil input.In contrast,the bacterial branched GDGTs(brGDGTs)were affected,to some extent,by soil input,depending on the distance to the lakeshore.The soil input of brGDGTs was enhanced during an episode of abnormal rainfall(flood).Moreover,the large variation of isoGDGTs indicates the in situ production under the anoxic condition in lake water.The paired increase in the GDGT-0/Cren ratio and GDGT concentration might be diagnostic of flooding events in ancient times.

关键词： GDGTs Lake Liangzi terrigenous input monitoring environmental geology

Distribution of glycerol dialkyl glycerol tetraethers in surface soils along an altitudinal transect at cold and humid Mountain Changbai:Implications for the reconstruction of paleoaltimetry and paleoclimate

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Science China Earth Sciences 2018年第7期61卷 925-939页

作者： Yue LI Shijin ZHAO Hongye PEI Shi QIAN Jingiie ZANG xinyue dang Huan YANG School of Earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Glycerol Dialkyl Glycerol Tetraethers(GDGTs)serve as important tools for the quantitative reconstruction of paleoclimate and paleoecology in both continental and marine environments.Previous studies of GDGTs in the terrestrial environments focused primarily on the soils from the relatively warm-humid or cold-dry regions.However,it is still unclear how GDGTs respond to environmental variables in the cold-humid regions.Here,we collected soils along an altitudinal transect of Mountain(Mt.)Changbai,which has a typical cold-humid climate,to investigate the distribution of GDGTs and the response of GDGT-based proxies to changes in climate along the transect.The shift in the distribution of archaeal isoprenoidal GDGTs(iso GDGTs)revealed that the archaeal community varied significantly along the transect,which can affect the relationship between TEX_(86)and mean annual air temperature(MAT).In addition,the increased temperature seasonality at higher altitudes exerted a significant impact on TEX_(86).We proposed a global calibration of TEX_(86)for the growing season temperature reconstruction in the soil environments:T=85.19×TEX_(86)-46.30(R^2=0.84,p0.55 are diagnostic for the c

关键词：古气候甘油潮湿土壤表面分发环境变量寒冷

麦季施磷量对小麦-玉米轮作产量及土壤有效磷的影响

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麦类作物学报 2024年第2期44卷 185-194页

作者：陈丽寇心悦党亚爱牛一楠包书尚沈玉芳西北农林科技大学资源环境学院陕西杨凌712100 西北农林科技大学理学院陕西杨凌712100

为提高陕西关中地区小麦-玉米轮作体系磷素利用率和节本增效,以及筛选合理的磷肥施用方式,于2018-2021年进行连续3年的仅小麦季一次施磷的田间定位试验,通过设置0、75、150、225和300 kg·hm^(-2)5个施磷(P2O5)水平,分析了麦季施磷量对... 详细信息

为提高陕西关中地区小麦-玉米轮作体系磷素利用率和节本增效,以及筛选合理的磷肥施用方式,于2018-2021年进行连续3年的仅小麦季一次施磷的田间定位试验,通过设置0、75、150、225和300 kg·hm^(-2)5个施磷(P2O5)水平,分析了麦季施磷量对小麦-玉米轮作产量、生物量、植株磷积累转运及土壤有效磷含量的影响。结果表明,与不施磷处理相比,施磷处理下小麦和小麦-玉米周年籽粒产量分别提高29.38%~40.95%和15.72%~24.57%,成熟期生物产量分别提高18.56%~34.19%和12.84%~23.29%,花前干物质转运量分别提高31.65%~63.33%和27.79%~52.47%,成熟期磷积累量分别提高37.08%~54.67%和39.54%~44.38%,磷素转运量分别提高90.82%~165.63%和44.06%~58.27%。通过进一步回归分析发现,实现小麦季和小麦-玉米周年最高产量的施磷量分别为207和201 kg·hm^(-2);若综合考虑粮食安全、环境安全和肥料利用率,以95%的小麦最高产量为实际目标,小麦季施磷量仅为130 kg·hm^(-2),两个最高产量的施磷量分别降低37.20%和35.32%,磷肥利用率分别提高2.27和2.87个百分点,小麦成熟期和玉米成熟期土壤有效磷含量分别为17.96和12.31 mg·kg^(-1)。因此,陕西省关中小麦-玉米轮作区麦季一次施用磷肥可实现小麦和小麦玉米周年高产稳产,本试验条件下130 kg·hm^(-2)为满足较高的轮作产量和磷肥利用率的适宜麦季施磷水平。

关键词：施磷量小麦-玉米轮作产量养分土壤有效磷

不同方法测定四氯虫酰胺和虫螨腈对小菜蛾生物活性的温度系数

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农药 2024年第1期63卷 63-66,78页

作者：安静杰郭江龙耿欣月高占林党志红李耀发河北省农林科学院植物保护研究所河北省农业有害生物综合防治工程技术研究中心农业农村部华北北部作物有害生物综合治理重点实验室河北保定071000

[目的]评价不同生物活性测定方法对杀虫剂温度效应的影响。[方法]分别采用食料浸渍法、浸虫法和点滴法测定四氯虫酰胺和虫螨腈对小菜蛾的生物活性,分析了其随温度变化的趋势。[结果]对于正温度效应杀虫剂四氯虫酰胺,采用食料浸渍法时其... 详细信息

[目的]评价不同生物活性测定方法对杀虫剂温度效应的影响。[方法]分别采用食料浸渍法、浸虫法和点滴法测定四氯虫酰胺和虫螨腈对小菜蛾的生物活性,分析了其随温度变化的趋势。[结果]对于正温度效应杀虫剂四氯虫酰胺,采用食料浸渍法时其活性随温度的升高(15~35℃)增加了99.15倍,呈强正温度效应,而另外2种方法表现为弱正温度效应。食料浸渍法测定时生物活性不受温度影响的虫螨腈,采用浸虫法和点滴法测定时,却表现出了+5.50和+3.50的弱温度效应。采用食料浸渍法时四氯虫酰胺和虫螨腈35℃时的温度系数分别为+99.15和+1.58,差异显著,而采用浸虫法和点滴法时2者温度系数相近。[结论]测定方法的选择显著地影响了正温度系数药剂四氯虫酰胺对小菜蛾生物活性的温度系数,而无温度效应药剂虫螨腈对小菜蛾生物活性没有受到显著影响。

关键词：四氯虫酰胺虫螨腈温度效应小菜蛾

Comparison of paleotemperature reconstructions using microbial tetraether thermometers of the Chinese loess-paleosol sequence for the past 350000 years

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Science China Earth Sciences 2017年第6期60卷 1159-1170页

作者： TANG ChangYan YANG Huan dang xinyue XIE ShuCheng State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Wuhan 430074 China

The recently proposed global and local calibrations for the mean annual air temperature(MAT) reconstruction on the basis of 5-and 6-methyl brGDGTs have rarely been applied to the Chinese LPS yet, leaving the applicability of these calibrations unclear. Here, we used the improved chromatography method to analyze 198 loess-paleosol samples from the Weinan section in the southern CLP for the past 350 kyr. The 6-methyl brGDGTs comprise a major proportion of total brGDGTs, pointing to alkaline conditions for most soil samples from the Weinan LPS. The decoupled profile variation of MBT′6ME and MBT′_(5ME) suggests their response to different enviromental factors, possibly soil pH(or soil moisture) and temperature, respectively. This discrimination further corraborates that temperature and monsoonal precipitation were not in phase during the last four deglaciations on the CLP. Temperature estimates for the six calibrations tested show similar trends but remarkably differ in amplitudes. The soil moisture appears to affect the global MBT′/CBT calibration, the global MATmr calibration(a calibration based on the multiple linear regression) and the Chinese local SSM(Stepwise Selection Method) calibration, resulting in a significant underestimation of late Holocene temperature. In contrast, the dry climate has no effect on the global MBT′5ME calibration. Of the six calibrations,only the Chinese local SSM calibration and global MATmr calibration produce temperature variation amplitude over the past 350 ka that is consistent with other independent proxy data. The recently proposed local calibrations based on 5-and 6-methyl brGDGTs for North China yield the amplitude of temperature changes that is much larger than the results determined by other approaches.All the six calibrations have their own weakness in the MAT reconstruction, due partly to the inconsistency between the brGDGT distribution in the Weinan LPS and the modern soils used to establish these calibrations.

关键词：黄土-古土壤序列温度计中国微生物古温度温度校准多元线性回归土壤样品

Environmental impacts on the distribution of microbial tetraether lipids in Chinese lakes with contrasting pH: Implications for lacustrine paleoenvironmental reconstructions

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Science China Earth Sciences 2016年第5期59卷 939-950页

作者： dang xinyue XUE JianTao YANG Huan XIE ShuCheng School of Earth Sciences China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Glycerol dialkyl glycerol tetraethers(GDGTs) in lake sediments are useful biomarkers for the continental paleoclimatic reconstruction. However, the environmental controls on the distribution of these compounds, in particular the 6-methyl isomers of bacterial branched GDGTs(bGDGTs), in the lakes with contrasting pH, are still unknown, hindering their application for paleo-reconstructions. Here, we investigated the environmental impacts on the distribution of GDGTs in 17 alkaline lakes and 1 acid lake in China. It was found that the dissolved oxygen content in water column may have an impact on the distribution of archaeal isoprenoid GDGTs(iGDGTs) by causing the change in archaeal communities. The ratio of GDGT-0/crenarchaeol increases with decreasing oxygen content, indicating that the relative abundance of anaerobic methanogenic archaea or Miscellaneous Crenarchaeotic Group(MCG) vs. aerobic Thaumarchaeota is controlled by the oxygen content dissolved in water of these lakes. Thaumarchaeota are likely to contribute only a small proportion of iGDGTs in the relatively oxygen-depleted lakes, and thus TEX_(86) is not suitable for the reconstruction of the surface temperature of these lakes. The abundance ratio of iGDGTs to bGDGTs(R_(i/b)) appears to show no relationship with water pH in all the lakes, but exhibits a significant positive correlation with the water depth of the acid Lake Qinghai in Tengchong. As expected, the methylation degree of bGDGTs(MBT′) was found to correlate with both mean annual air temperature(MAT) and water pH, and the cyclization degree of bGDGTs(CBT) correlates only with water pH in these lakes. However, the MBT′_(5ME), an index to measure the methylation degree of 5-methyl bGDGTs, exhibits no relationship with MAT, whereas MBT′_(6ME), the methylation degree of 6-methyl bGDGTs, was found to correlate significantly with MAT. This is opposite to the situation observed in the global soils, pointing to a different adaptation of b GDGT-producing bacteria to environmental variables or different m

关键词：湖泊沉积物 pH值控制微生物来源古环境重建中国溶解氧含量同分异构体脂质

Population-induced lake eutrophication increases the archaeal methanogenesis: Evidence from Shahu Lake in central China

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Population-induced lake eutrophication increases the archaea...

凝结芽孢杆菌BC2000联合鞣花酸改善高脂饮食诱导的小鼠胰岛素抵抗

2019年中国地球科学联合学术年会

作者： Zicong Li Xu Chen Hongye Pei Jiachen Fan Rui Sun xinyue dang Huan Yang Shucheng Xie China University of Geosciences

Lakes and wetlands are a significant methane source to the atmosphere and most of the methane is generated by archaeal methanogenesis processes in lacustrine setting. As numerous researches have focused on the ecological effects of eutrophication to lacustrine ecosystem, however, few attempts was made to evaluate how eutrophication

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食品科学 2023年第5期44卷 85-95页

作者：党红阳李欣悦齐策王亮孙进新疆大学生命科学与技术学院新疆乌鲁木齐830046 青岛大学营养与健康研究院山东青岛266000

目的:探讨凝结芽孢杆菌BC2000提高鞣花酸(ellagic acid,EA)缓解小鼠胰岛素抵抗的效果及与肠道菌群重塑的关系。方法:将50只C57BL/6J小鼠随机分为5组:低脂饮食(low fat diet,LFD)组、高脂饮食(high fat diet,HFD)组、凝结芽孢杆菌BC2000... 详细信息

目的:探讨凝结芽孢杆菌BC2000提高鞣花酸(ellagic acid,EA)缓解小鼠胰岛素抵抗的效果及与肠道菌群重塑的关系。方法:将50只C57BL/6J小鼠随机分为5组:低脂饮食(low fat diet,LFD)组、高脂饮食(high fat diet,HFD)组、凝结芽孢杆菌BC2000联合EA干预组(HFD+EA+BC2000组)、凝结芽孢杆菌BC30联合EA干预组(HFD+EA+BC30组)和EA干预组(HFD+EA组),进行10周干预,测定小鼠相关生理生化指标,对炎性细胞因子进行分析,同时对肝脏和睾周脂肪进行组织学分析并对盲肠内容物进行肠道菌群结构分析。结果显示,BC2000和EA联合食用改善了高脂饮食诱导的小鼠肥胖,减轻了脂肪细胞肥大和肝脏脂肪变性,显著降低了高脂饲喂小鼠血浆的胰岛素、总胆固醇、低密度脂蛋白胆固醇水平和胰岛素抵抗指数(P<0.05),显著降低血浆黏膜屏障生物标志物脂多糖和连蛋白(Zonulin)水平(P<0.05),以及慢性炎症标志物肿瘤坏死因子α、超敏C反应蛋白和白细胞介素6(P<0.05)水平,提高盲肠放线菌门(Actinobacteria)和乳杆菌属(Lactobacillus)相对丰度,降低脱硫弧菌属(Desulfovibrio)的相对丰度,改善肠道菌群结构。综上,凝结芽孢杆菌BC2000通过改善肠道菌群结构提高了EA调节糖脂代谢和胰岛素抵抗的作用,实验结果可为将凝结芽孢杆菌BC2000作为益生菌应用于食品提供进一步的理论依据。

关键词：凝结芽孢杆菌鞣花酸高脂小鼠肠道菌群胰岛素抵抗

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CO_(2)电催化还原产合成气研究进展

化工进展 2022年第3期41卷 1224-1240页

作者：华亚妮冯少广党欣悦郝文斌张保文高展西安交通大学化学工程与技术学院陕西西安710049 佛燃能源集团股份有限公司广东佛山528000

CO_(2)电催化还原产合成气是通过CO_(2)资源化利用实现碳中和的有效途径之一,但仍存在过电位高、选择性差、难以精准调控合成气组成比例等问题。本文综述了CO_(2)电催化还原产合成气的催化剂研究进展,包括金属催化剂、金属配合物催化剂... 详细信息

CO_(2)电催化还原产合成气是通过CO_(2)资源化利用实现碳中和的有效途径之一,但仍存在过电位高、选择性差、难以精准调控合成气组成比例等问题。本文综述了CO_(2)电催化还原产合成气的催化剂研究进展,包括金属催化剂、金属配合物催化剂、金属氧化物及硫化物催化剂、金属单原子催化剂以及非金属催化剂等;进一步地,概述了H型电解池、连续流电解池、固体氧化物电解池以及膜反应器电解池等电化学反应池特征。在此基础上,总结了提升CO_(2)电催化还原产合成气效率的有效策略,包括阳极反应耦合、双活性位催化剂结构设计以及催化剂多级形貌调控等。最后探讨了CO_(2)电催化还原产合成气领域未来的发展方向:通过机器学习辅助催化剂设计筛选;结合多尺度模拟理解电化学界面过程;利用原位表征技术探究反应机理等。

关键词：二氧化碳电催化还原合成气催化剂

Hyperterpenoids A and B:Two pairs of unprecedented 6/6/4/6/6 polycyclic cyclobutane meroterpenoids with potent neuroprotective and anti-inflammatory activities from Hypericum beanii

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Chinese Chemical Letters 2021年第7期32卷 2338-2341页

作者： Bo Zhen xinyue Suo Jun dang Huilan Yue Yanduo Tao Jia-Jia Wang Li Li Ming-Bao Lin Qi Hou Wei-Ping Wang Xiao-Liang Wang Jian-Dong Jiang Teng-Fei Ji State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Key Laboratory of Tibetan Medicine Research Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China

Hyperterpenoid A(1)and B(2),two pairs of enantiomers,with an unprecedented 6/6/4/6/6 polycyclic skeleton,along with one known compoud hypermonone A(3)were isolated from Hypericum beanii.The racemate(±)-1 and(±)-2 were successfully separated into the two optically pure enantiomers(ee>99%)using a preparative HPLC system.Their absolute configurations were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction method.The related plausible biogenetic pathways were pre sented.Compound 1-3 showed significant neuroprotective activity and potential antiinflammatory activity.The result that(+)-2 and(-)-2 presented different anti-inflammatory properties,may lead us to new discovery of structure activity relationship between racemates,enantiomers,and diastereomers,as well as further research regarding the binding of drugs to target proteins.

关键词： Hypericum beanii Meroterpenoids (±)-Hyperterpenoid A and B Anti-inflammatory activity Neuroprotective activity