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Plant-microbial interactions inspired the discovery of novel sesquiterpenoid dimeric skeletons of hidden natural products from Hibiscus tiliaceus

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Chinese Chemical Letters 2024年第10期35卷 286-290页

作者： Deli Chen Jiawen Li Xudong Xu Zhaocui Sun Yun Yang Minghui Xu Hanqiao Liang Junshan Yang Hui Meng Guoxu Ma Jianhe Wei Hainan Branch of the institute of Medicinal Plant development(Hainan Provincial Key Laboratory of resources Conservation and development of Southern Medicine) Chinese Academy of Medical Sciences&Peking Union Medical CollegeHaikou 570311China institute of Medicinal Plant development Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China School of Pharmaceutical Science Hainan Medical UniversityHaikou 571199China Department of Biomedicine Beijing City UniversityBeijing 100094China

Hidden natural products are representative of defensive strategies produced in vivo in diseased plants,a process that is induced by the plant immune *** first transcriptome library of uninfected and pathogen infected Hibiscus tiliaceus stems was constructed by transcriptome sequencing technology,genes related to cadinene-type sesquiterpenoid biosynthesis were screened and combined with ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry(UPLC-QTOF-MS)analysis data,which indicated pathological tissue had potential to produce novel carbon skeletons of cadinane sesquiterpenoid ***,two cadinane-derived sesquiterpenoid dimers with unprecedented carbon skeletons,hibisceusanols A(1)and B(2)were isolated for the first time from the stems of *** induced by plant-microbial *** structures and absolute configurations were unambiguously established by spectroscopy,advanced chemistry development(ACD)and electronic circular dichroism(ECD)*** 1 and 2 exhibited significant antitumor activity in vitro with half maximal inhibitory concentration(IC_(5)0)values of 2.3–7.2μmol/*** anticancer effect was generated via the induction of Hep G2 cell apoptosis by inhibiting the phosphatidylinositol 3-kinase(PI3K)pathway.

关键词： Cadinane-derived sesquiterpenoid Anti-cancer PI3K Plant-microbial interactions

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Does urban technological innovation and cooperation promote its green development?Evidence from cities in the Beijing-Tianjin-Hebei urban agglomeration,China

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Journal of Geographical Sciences 2024年第10期34卷 1977-2002页

作者： WANG Kewen MA Haitao Key Laboratory of Regional Sustainable development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China

The internal technological innovation(IT)and external technological cooperation(ET)of a city are crucial drivers for its green development(GD).Although previous studies have extensively explored the effect of IT on GD,IT,ET and GD have not been integrated into the same framework to explore their *** panel data of 13 cities in the Beijing-Tianjin-Hebei urban agglomeration,this study revealed the spatio-temporal evolution of GD and analyzed the effects of IT and ET on GD from the perspective of baseline impact,spatial effect and synergy *** results demonstrate that the level of urban GD has upgraded and the difference in GD between cities has been narrowed though it decreases from the middle to both *** significantly promotes the growth of GD while ET has an inverted U-shaped effect on *** the influence of spatial spillover,IT has a U-shaped effect on the GD of neighboring cities while the effect of ET on neighboring GD is not ***,the interaction between IT and ET has not been effective,leading to an insignificant synergy effect on *** findings will provide reference for taking rational advantage of IT and ET to facilitate urban GD.

关键词： internal technological innovation external technological cooperation green development spatial spillover effect synergy effect Beijing-Tianjin-Hebei urban agglomeration

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Spatiotemporal variability of rain-on-snow events in the arid region of Northwest China

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Journal of Arid Land 2024年第4期16卷 483-499页

作者： YANG Zhiwei CHEN Rensheng LIU Zhangwen ZHAO Yanni LIU Yiwen WU Wentong Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Rain-on-snow(ROS)events involve rainfall on snow surfaces,and the occurrence of ROS events can exacerbate water scarcity and ecosystem vulnerability in the arid region of Northwest China(ARNC).In this study,using daily snow depth data and daily meteorological data from 68 meteorological stations provided by the China Meteorological Administration National Meteorological Information Centre,we investigated the spatiotemporal variability of ROS events in the ARNC from 1978 to 2015 and examined the factors affecting these events and possible changes of future ROS events in the *** results showed that ROS events in the ARNC mainly occurred from October to May of the following year and were largely distributed in the Qilian Mountains,Tianshan Mountains,Ili River Valley,Tacheng Prefecture,and Altay Prefecture,with the Ili River Valley,Tacheng City,and Altay Mountains exhibiting the most *** on the intensity of ROS events,the areas with the highest risk of flooding resulting from ROS events in the ARNC were the Tianshan Mountains,Ili River Valley,Tacheng City,and Altay *** number and intensity of ROS events in the ARNC largely increased from 1978 to 2015,mainly influenced by air temperature and the number of rainfall ***,due to the snowpack abundance in areas experiencing frequent ROS events in the ARNC,snowpack changes exerted slight impact on ROS events,which is a temporary ***,elevation imposed lesser impact on ROS events in the ARNC than other *** the ARNC,the start time of rainfall and the end time of snowpack gradually advanced from the spring of the current year to the winter of the previous year,while the end time of rainfall and the start time of snowpack gradually delayed from autumn to *** may lead to more ROS events in winter in the *** results could provide a sound basis for managing water resources and mitigating related disasters caused by ROS events in the ARNC.

关键词： rain-on-snow events snowpack snowmelt climate change Spearman's rank correlation arid region of Northwest China

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Responses of soil stoichiometry and soil enzyme activities in the different distance around opencast coal mine of the Hulun Buir Grassland of China

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International Journal of Coal Science & Technology 2024年第1期11卷 221-231页

作者： Yinli Bi Nan Guo Yanxu Zhang Xianglei Li Ziheng Song State Key Laboratory for Fine Exploration and Intelligent development of Coal resources China University of Mining and Technology(Beijing)Beijing100083China institute of Ecological Environment Restoration in Mine Areas of West China Xi’an University of Science and TechnologyXi’an710054China

The objectives of this study were to explore the changes in soil stoichiometry and enzyme activities at different distances from an opencast coal mine in the Hulun Buir Grassland of China. Four transects were established on north and east sides of the opencast coal mining area, and samples were collected at 50 m, 550 m, and 1550 m from the pit on each transect. Control samples were collected from a grassland station 8 km from the opencast coal mining area that was not disturbed by mining. Four replicate soil samples were collected at each point on the four transects. Soil physicochemical properties and enzyme activities were determined, and correlations between soil properties and stoichiometric ratios and enzyme activities were explored using redundancy analysis. The increase in distance from mining did not significantly affect soil properties, although soil urease activity was significantly lower than that of the control area. Soil properties 1550 m from the mine pit were similar to those at the grassland control. In addition, soil total nitrogen had the greatest effect on soil stoichiometry, and soil total potassium had the greatest effect on soil enzyme activities. Coal dust from opencast mining might be the main factor affecting soil stoichiometry and enzyme activities. The results of this study provide direction for the next step in studying the influence of mining areas on soil properties and processes.

关键词： Opencast coal mine Soil stoichiometry Soil enzyme activities Distance Grassland

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Spatiotemporal Variability and Environmental Controls of Temperature Sensitivity of Ecosystem Respiration across the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第9期41卷 1821-1842页

作者： Danrui SHENG Xianhong MENG Shaoying WANG Zhaoguo LI Lunyu SHANG Hao CHEN Lin ZHAO Mingshan DENG Hanlin NIU Pengfei XU Xiaohu WEN Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Zoige Plateau Wetlands Ecosystem Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Key Laboratory of Ecological Safety and Sustainable development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Warming-induced carbon loss via ecosystem respiration(R_(e))is probably intensifying in the alpine grassland ecosystem of the Tibetan Plateau owing to more accelerated warming and the higher temperature sensitivity of R_(e)(Q_(10)).However,little is known about the patterns and controlling factors of Q_(10)on the plateau,impeding the comprehension of the intensity of terrestrial carbon-climate feedbacks for these sensitive and vulnerable ***,we synthesized and analyzed multiyear observations from 14 sites to systematically compare the spatiotemporal variations of Q_(10)values in diverse climate zones and ecosystems,and further explore the relationships between Q_(10)and environmental ***,structural equation modeling was utilized to identify the direct and indirect factors predicting Q_(10)values during the annual,growing,and non-growing *** results indicated that the estimated Q_(10)values were strongly dependent on temperature,generally,with the average Q_(10)during different time periods increasing with air temperature and soil temperature at different measurement depths(5 cm,10 cm,20 cm).The Q_(10)values differentiated among ecosystems and climatic zones,with warming-induced Q_(10)declines being stronger in colder regions than elsewhere based on spatial *** was the most cardinal factor in predicting annual Q_(10)values,significantly and positively correlated with Q_(10).Soil temperature(Ts)was identified as the other powerful predictor for Q_(10),and the negative Q_(10)-Ts relationship demonstrates a larger terrestrial carbon loss potentiality in colder than in warmer regions in response to global *** that the interpretations of the effect of soil moisture on Q_(10)were complicated,reflected in a significant positive relationship between Q_(10)and soil moisture during the growing season and a strong quadratic correlation between the two during the annual and non-growing *** findings are conducive to imp

关键词： carbon cycle eddy covariance measurements ecosystem respiration Q_(10)value Tibetan Plateau climate change

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Study of inter-well interference in shale gas reservoirs by a robust production data analysis method based on deconvolution

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Petroleum Science 2024年第4期21卷 2502-2519页

作者： Wen-Chao Liu Cheng-Cheng Qiao Ping Wang Wen-Song Huang Xiang-Wen Kong Yu-Ping Sun He-Dong Sun Yue-Peng Jia School of Civil and Resource Engineering University of Science and Technology Beijing PetroChina Research institute of Petroleum Exploration and development

In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering, this study proposes a robust production data analysis method based on deconvolution, which is used for multi-well inter-well interference research. In this study, a multi-well conceptual trilinear seepage model for multi-stage fractured horizontal wells was established, and its Laplace solutions under two different outer boundary conditions were obtained. Then, an improved pressure deconvolution algorithm was used to normalize the scattered production data. Furthermore, the typical curve fitting was carried out using the production data and the seepage model solution. Finally,some reservoir parameters and fracturing parameters were interpreted, and the intensity of inter-well interference was compared. The effectiveness of the method was verified by analyzing the production dynamic data of six shale gas wells in Duvernay area. The results showed that the fitting effect of typical curves was greatly improved due to the mutual restriction between deconvolution calculation parameter debugging and seepage model parameter debugging. Besides, by using the morphological characteristics of the log-log typical curves and the time corresponding to the intersection point of the log-log typical curves of two models under different outer boundary conditions, the strength of the interference between wells on the same well platform was well judged. This work can provide a reference for the optimization of well spacing and hydraulic fracturing measures for shale gas wells.

关键词： Shale gas Inter-well interference Deconvolution Production data analysis Typical curves Multi-stage fractured horizontal well

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Different responses of two adjacent artificial beaches to Typhoon Hato in Zhuhai,China

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Journal of Oceanology and Limnology 2024年第2期42卷 511-521页

作者： Jun ZHU Qing WANG Chao ZHAN Fengjuan SUN Wenhao HUA Jianhui LIU Hongshuai QI Yu YANG Coastal Research institute Ludong UniversityYantai 264025China Third institute of Oceanography Ministry of Natural ResourcesXiamen 261005China

Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach(XL beach)and Meiliwan Beach(ML beach)in Zhuhai,China,were studied after Super Typhoon *** this study,a fully nonlinear Boussinesq wave model(FUNWAVE)-Total Variation Diminishing(TVD)was used to distinguish the main impact factors,their relative contributions,and the hydrodynamic mechanisms underlying the different beach *** show that compared to the ML beach,the main reason for the relatively weak erosion on Xiangluwan(XL)beach was the smaller beach berm height(accounting for approximately 75.9%of the erosion response).Regarding the beach with a higher berm,the stronger wave-induced undertow flow,along with the higher sediment concentration,led to a higher offshore sediment transport flux,resulting in more severe erosion relative to the beach with a smaller berm *** second most important reason explaining the weak erosion on XL beach was the absence of seawalls(accounting for approximately 17.9%of the erosion response).Wave reflection induced by the seawall could cause higher suspended sediment concentration,resulting in a toe scouring near the *** offshore submerged breakwater protected XL beach slightly(accounting for approximately 6.1%of the erosion response).Due to the higher water level induced by storm surge,most of the wave energy could penetrate through the submerged *** effect of the larger berm width of XL beach was *** to the beach with a larger berm width,the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration,without significant changes in the erosion/deposition *** of this,the larger berm width could reduce the wave energy reaching the *** study of the storm stability of artificial beaches may be applied to beach restoration design.

关键词： beach erosion berm height berm width seawall fully nonlinear Boussinesq wave model(FUNWAVE)

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Flume experiments to study fine-grain migration and its impact on slope stability

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Journal of Mountain Science 2024年第10期21卷 3552-3566页

作者： WANG Baoliang WANG Quanwei LI Yong YAO Zhenguo WANG Hongfei Yellow River Engineering Consulting Co.Ltd. Zhengzhou 450003China Key Laboratory of water Management and water Security for Yellow River Basin Ministry of Water Resources(under construction)Zhengzhou 450003China institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Key Laboratory of mountain Hazards and Surface Process Chinese Academy of SciencesChengdu 610041China

Fine grains migration is a primary cause of landslides and debris *** study investigates the effect of fine-grain migration on slope failure through flume experiments,focusing on the spatiotemporal characteristics and mechanisms of slope stability.A series of artificial rainfall flume experiments with varying rainfall intensities and slopes were conducted using soil samples collected from Wei Jia *** experiments monitored pore-water pressure,grain migration,and failure ***-size distribution parameters(μand Dc)were analyzed to understand the migration path and accumulation of fine *** experiments reveal that fine-grain migration significantly alters soil structure,leading to random blockage and interconnection of internal pore *** changes result in fluctuating pore-water pressure distributions and uneven fine-grain accumulation,critical factors in slope *** failures occur randomly and intermittently,influenced by fine-grain content in runoff and resulting pore-water pressure *** study highlights that fine-grain migration plays a vital role in slope stability,with significant implications for predicting and mitigating slope *** stochastic nature of fine-grain migration and its impact on soil properties should be incorporated into predictive models to enhance their accuracy and reliability.

关键词： Fine-grain migration Slope stability Pore-water pressure Artificial rainfall Soil structure Flume experiments

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Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 221-233页

作者：刘生鹏 XU Zhi ZHANG Xinyuan WEI Huan XIONG Yun DING Yigang HUANG Wenbo 许莉莉 Engineering Research Center of Phosphorus resources development and Utilization of Ministry of Education Key Laboratory for Green Chemical Process of Ministry of EducationSchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443007China School of Technology Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China

Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites.

关键词： polyphosphazene thermoplastic polyurethane flame retardancy aluminum hypophosphite surface polymerization

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Drivers,Trends,and Patterns of Changing Vegetation-greenness in Nansha Islands,China from 2016 to 2022

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Chinese Geographical Science 2024年第4期34卷 662-673页

作者： TANG Jiasheng FU Dongjie SU Fenzhen YU Hao WANG Xinhui Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Collaborative Innovation Center of South China Sea Studies Nanjing 210023China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing North-Star Technology development Co. LtdBeijing 100120China

Changes in vegetation status generally also represents changes in the ecological health of islands and reefs(IRs).However,studies are limited of drivers and trends of vegetation change of Nansha Islands,China and how they relate to climate change and human *** resolve this limitation,we studied changes to the Normalized Difference Vegetation Index(NDVI)vegetation-greenness index for 22 IRs of Nansha Islands during normal and extreme *** of vegetation greenness were analyzed using Sen's slope and Mann-Kendall test at two spatial scales(pixel and island),and driving factor analyses were performed by time-lagged partial correlation *** were related to impacts from human activities and climatic factors under normal(temperature,precipitation,radiation,and Normalized Difference Built-up Index(NDBI))and extreme conditions(wind speed and latitude of IRs)from 2016 to *** showed:1)among the 22 IRs,NDVI increased/decreased significantly in 15/4 IRs,*** Reef had the highest NDVI change-rate(0.48%/mon),and Zhongye Island had the lowest(–0.29%/mon).Local spatial patterns were in one of two forms:dotted-form,and degradation in banded-form.2)Under normal conditions,human activities(characterized by NDBI)had higher impacts on vegetation-greenness than other factors.3)Under extreme conditions,wind speed(R^(2)=0.2337,Pdevelopment of Nansha Islands and the United Nations‘Ocean Decade’initiative.

关键词： island and reefs(IRs) Normalized Difference Vegetation Index(NDVI) vegetation-greenness change-rate Sen's slope Nansha Islands China

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