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Spatial patterns in natural Picea crassifolia forests of northwestern China,as basis for close-to-nature forestry

Journal of Mountain Science 2018年第9期15卷 1909-1919页

作者： HE Zhi-bin FANG Shu CHEN Long-fei DU Jun ZHU Xi lin peng-fei linze Inland River Basin Research Station Chinese Ecosystem Research NetworkKey Laboratory of Eco-hydrology of Inland River BasinNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Close-to-nature forest management has been proposed as an effective method for improving the quality of plantation forests. Knowledge of spatial distribution patterns, structure, and succession trajectories in natural forests can provide guidelines for the establishment of close-to-nature forest plantations. Such knowledge is lacking in natural spruce(Picea crassifolia) forests in the Qilian Mountains of China, impeding the establishment of production forests. We conducted a case study in the Qilian Mountains to analyze the relationships between the naturally-formed forest patches and terrain factors, spatial heterogeneity of stand characteristics, and stand structure following harvesting disturbance. Our results suggested that spruce plantations will be effective on the N, NE, and NW slopes, at elevations between 2700 and 3300 m, and on slopes ranging from 15° to 45°. Further, planted forest patches should occupy 64% of the slope area on semi-shady slopes(NE, NW). Spatial patterns in the studied forest exhibited a strong scale-effect, and an area of 0.25 ha could be used as the most efficient plot scale for the management of spruce plantations. Partial logging is an effective method for the conversion of spruce planted forests into nearnatural forests, and the intensity of partial logging can be determined from the negative exponential function relationship between stand density and DBH. Our results provided critical information for the development of spruce plantations and conversion of existing plantations.

关键词： Picea crassifolia spruce Close-to-nature forestry Spatial patterns Qilian Mountains

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Citrinal A,a novel tricyclic derivative of citrinin,from an algicolous fungus Penicillium sp.i-1-1

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Chinese Chemical Letters 2009年第8期20卷 917-920页

作者： Tian Jiao Zhu lin Du peng fei Hao Zhen Jian lin Qian Qun Gu Key Laboratory of Marine Drugs Chinese Ministry of Education School of Medicine and Pharmacy Ocean University of China Qingdao 266003 PR China

Citrinal A （1）, a novel tricyclic compound with a rare tetrahydro-2H-benzofuro[7-b] [ 1,4]dioxin-9（3H）-one skeleton, along with two known related compounds, citrinin （2） and 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran （3） were isolated from an algicolous fungus Penicillium sp. i-1-1. The structure and stereochemistry of 1 were determined by comprehensive spectral and biogenic analysis. Its cytotoxic effects on the A-549 and HL-60 cell lines were evaluated. ？2009 Qian Qun Gu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Citrinal Algicolous fungus Penicillium

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Historical Trends in Surface Air Temperature Estimated by Ensemble Empirical Mode Decomposition and Least Squares linear Fitting

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Atmospheric and Oceanic Science Letters 2015年第1期8卷 10-16页

作者： lin peng-fei FENG Xiao-Li LIU Juan-Juan State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics (IAP) Chinese Academy of Sciences Meteorological Observatory Huangnan Tibetan Autonomous Prefecture of Qinghai Province Ministry of Education Key Laboratory of Meteorological Disaster of Cooperation of Ministries and Provincial Governments and College of Atmospheric Sciences Nanjing University of Information Science and Technology

Ensemble empirical mode decomposition(EEMD) and least squares linear fitting(LSLF) are applied to estimate the historical trends of surface air temperature(SAT) from observations and Coupled Model Intercomparison Project Phase 5(CMIP5) simulations during the period 1901–2005. The magnitudes of trends estimated by the two approaches are comparable. The trend calculated by the EEMD approach is larger than that by the LSLF approach in most(23/27) of the models during 1901–2005. During the slow warming period, the EEMD trend is smaller than the LSLF trend. The rootmean-square errors(RMSEs) between the raw and reconstructed times series by the LSLF approach are larger than those by the EEMD trend component and multi-decadal variability components during 1901–2005 in most of the models and observations. During 1901–70(or 1971–2005), the RMSEs between the raw and reconstructed times series by LSLF are larger than those by the EEMD trend component. In this sense, the EEMD trend is a better choice to obtain the climate trends in observations and CMIP5 models, especially for short time periods. This is because the trend estimated by LSLF cannot capture the internal variability and the cooling in some years. The estimated global warming rates(trend) are consistently larger(smaller) than those from observations in 11 of 27 CMIP5 models during 1901–2005 in the slow and rapid warming periods. This implies these 11 models have consistent responses to greenhouse gases for any period.

关键词： climate trend surface air temperature CMIP5 LSLF E

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光催化CO_(2)静电纺丝MOF膜的制备与性能研究

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膜科学与技术 2024年第4期44卷 17-27页

作者：林鹏飞何欣平吴东云董晨曦赵磊伊春海郭佳鑫西安交通大学化学工程与技术学院西安710049 陕西延长石油(集团)有限责任公司研究院西安710065 盐城职业技术学院纺织服装学院盐城224005

金属有机骨架(MOFs)因其在多相催化中的应用而受到广泛的关注,但是与反应混合物的分离效果差限制了其实际应用.MOFs薄膜在光催化分解污染物方面有着广泛的应用,但在光催化CO_(2)领域很少有报道,所以制备适合光催化CO_(2)高效还原的MOFs... 详细信息

金属有机骨架(MOFs)因其在多相催化中的应用而受到广泛的关注,但是与反应混合物的分离效果差限制了其实际应用.MOFs薄膜在光催化分解污染物方面有着广泛的应用,但在光催化CO_(2)领域很少有报道,所以制备适合光催化CO_(2)高效还原的MOFs薄膜十分有必要.本研究通过静电纺丝将ZIF-67混纺在聚丙烯腈(PAN)纳米纤维膜(NFMs)内,再进行热稳定处理,得到SZIF-67/PAN NFMs,表征了其形貌特征、化学成分、光催化性能以及光电性能等.结果表明,SZIF-67/PAN NFMs由于可见光响应的改善、光热转化能力和耐溶剂能力的提高,对CO_(2)的还原表现出优异的可见光驱动光催化活性,CO生成速率达到12000μmol/(g·h),重复使用3次后光催化性能仍保持在85.4%.此外,还提出了CO_(2)全面光还原的可能机理:光敏剂通过可见光激发产生电子注入SZIF-67/PAN NFMs中Co活性点位,吸附在Co活性点位上的电子进一步转移到CO_(2)上并与质子形成CO.最后CO从NFMs上解吸,实现光催化CO_(2)到CO的转化.

关键词： MOFs ZIF-67 热稳定静电纺丝膜光催化 CO_(2)还原

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Estimation of the surface heat budget over the South China Sea

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Atmospheric and Oceanic Science Letters 2016年第3期9卷 191-197页

作者： FENG Bao-Xin LIU Hai-Long lin peng-fei WANG Qi College of Physical and Environmental Oceanography Ocean University of China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences

In situ data are employed to evaluate five gridded surface heat flux datasets over the South China Sea. The surface heat budgets for these gridded datasets are computed. The authors find that the gridded datasets tend to underestimate both the solar radiation and sensible heat flux in general, while the latent heat fluxes are close to the observations, except for that of NOC unadjusted version 2 （NOC2）, which overestimates both the latent and sensible heat flux. The underestimation of solar radiation also indicates that the gridded datasets might underestimate the surface heat budget. The net surface heat flux of the five gridded datasets is always positive. However, the net surface heat flux of COADS, NOC1, NOC2, and OAFlux, in the range 48-56 W m-2, is around twofold more than that of NOC1 a （22 W m-2）. The budget for NOC2 is smaller than that of NOC1 and OAFlux, by approximately 49 W m-2, because of the large release of latent heat flux. Based on the comparison, the authors believe that the net surface heat flux over the South China Sea should be higher than 56 W m-2, which is significantly larger （around 10%-20%） than previous estimations.

关键词： Shortwave radiation netheat flux heat budget SouthChina Sea

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Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing lin Dong-Sheng Ji peng-fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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FGOALS高分辨率气候模式系统模式研制与应用综述

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大气科学 2024年第1期48卷 200-217页

作者：俞永强安博刘海龙包庆林鹏飞何编郑伟鹏栾贻花白文蓉李恬燕中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG) 北京100029 中国科学院大学北京100049

当今气候系统模式发展的重要趋势之一,是通过提高模式的空间分辨率,改进对气候系统中多尺度相互作用过程和极端事件的模拟能力。过去5年里,中国科学院大气物理研究所发展并完善了25 km分辨率大气环流分量模式FAMIL2.2、1/10°分辨率海... 详细信息

当今气候系统模式发展的重要趋势之一,是通过提高模式的空间分辨率,改进对气候系统中多尺度相互作用过程和极端事件的模拟能力。过去5年里,中国科学院大气物理研究所发展并完善了25 km分辨率大气环流分量模式FAMIL2.2、1/10°分辨率海洋环流分量模式LICOM3.0,并以此为基础建立了高分辨率气候系统模式FGOALS-f3-H。利用上述高分辨率模式,开展了大量的数值模拟试验和预报/预测研究,其中包括国际耦合模式比较计划第六阶段(CMIP6)的高分辨率模式比较子计划(HighResMIP),建立了海洋环流预测系统(LFS)等。初步评估分析表明,相对于低分辨率模式,高分辨率模式对气候平均态和气候变率的模拟能力均有明显改进。其中高分辨率大气环流模式可以更好地模拟台风、极端降水事件,高分辨率海洋模式可以更好地模拟海洋中尺度涡旋和西边界流,而高分辨率耦合模式则可以更好重现中尺度海气相互作用过程、热带不稳定波动(TIW)等事件。

关键词：气候系统模式高分辨率多尺度相互作用国际耦合模式比较计划(CMIP)

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Assessment of Historical Climate Trends of Surface Air Temperature in CMIP5 Models

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 137-142页

作者： FENG Xiao-Li ZHI Hai lin peng-fei LIU Hai-Long Ministry of Education Key Laboratory of Meteorological Disaster of Cooperation of Ministries and Provincial Governments and College of Atmospheric Sciences Nanjing University of Information Science and Technology State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics (IAP)Chinese Academy of Sciences

This study assesses the historical climate trends of surface air temperature（SAT）, their spatial distributions, and the hindcast skills for SAT during 1901– 2000 from 24 Coupled Model Intercomparison Project Phase 5（CMIP5） models. For the global averaged SAT, most of the models（17/24） effectively captured the increasing trends（0.64°C/century for the ensemble mean） as the observed values（- 0.6°C/century） during the period of 1901–2000, particularly during a rapid warming period of 1970–2000 with the small model spread. In addition, most of the models（22/24） showed high hindcast skills（the correlation coefficient, R 〉 0.8）. For the spatial pattern of SAT, the models better simulated the relatively larger warming at the middle-to-high latitudes in the Northern Hemisphere than that in the Southern Hemisphere and the greater warming on the land than that in the ocean between 40°S and 40°N. The simulations underestimated the warming along some ocean boundaries but overestimated warming in the Arctic Ocean. Most of the coupled models were able to reproduce the large-scale features of SAT trends in most regions excluding Antarctica, some parts of the Pacific Ocean, the North Atlantic Ocean near Greenland, the southwestern Indian Ocean, and the Arctic Ocean. The outgoing longwave radiation（OLR） and incoming shortwave radiation（ISR） at the top of the atmosphere（TOA） and the downward longwave（LW） radiation and sensible heat flux at the surface had positive contributions to the increasing trends in most of the models.

关键词： CMIP5 surface air temperature trend warming

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Distribution of per-and polyfluoroalkyl substances in blood,serum,and urine of patients with liver cancer and associations with liver function biomarkers

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Journal of Environmental Sciences 2024年第5期139卷 418-427页

作者： Cao Dai lin peng Yanjie Li Zhendong Li Da Chen fei Wang Nan lin Department of Hepatobiliary Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630China School of Environment Guangdong Key Laboratory of Environmental Pollution and HealthJinan UniversityGuangzhou 510632China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China South China Institute of Environmental Sciences MEEGuangzhou 510655China

Studies have shown that per-and polyfluoroalkyl substances(PFASs)may be hepatotoxic in animals or ***,data on clinical epidemiology are very *** this study,21PFASs were determined in patients with liver diseases,with the highest median concentrations detected in the serum sample(26.7 ng/mL),followed by blood(10.7 ng/mL)and urine(5.02 ng/mL).Higher total PFAS concentrations were found in hepatocellular carcinoma(HCC)patients compared to non-HCC patients,with significant discrepancies in serum and blood ***,significant correlations were also found among PFAS concentrations and age,gender,body mass index(BMI),and liver function biomarkers *** example,PFAS concentrations are significantly higher in males than in females;Several serum PFASs concentrations increase with age and BMI,while the serum perfluorohexane sulfonic acid(PFHxS)concentrations are negatively correlated with *** addition,multiple regression models adjusted for age,gender and BMI found that increased serum perfluorobutane sulfonic acid(PFBS),perfluoroheptane sulfonic acid(PFHpS)and perfluorohexylphosphonic acid(PFHxPA)conentrations are correlated with elevated alkaline phosphatase(ALP),aspartate aminotransferase(AST),and alpha-fetoprotein(AFP)(plinical hepatotoxicity of PFAS.

关键词： Per-and polyfluoroalkyl substances(PFASs) Liver cancer Serum Blood Urine Liver function biomarkers

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Long-term surface air temperature trend and the possible impact on historical warming in CMIP5 models

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Atmospheric and Oceanic Science Letters 2016年第3期9卷 153-161页

作者： lin peng-fei FENG Xiao-Li ZHI Hai LIU Hai-Long WANG Li State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics(IAP) Chinese Academy of Sciences Meteorological Observatory Huangnan Tibetan Autonomous Prefecture Ministry of Education Key Laboratory of Meteorological Disaster of Cooperation of Ministries and Provincial Governments and College of Atmospheric Sciences Nanjing University of Information Science and Technology Emergency and Disaster Reduction Section Meteorological Bureau of Qinghai Province

Whether large trends exist in pre-industrial control （PICTL） runs is critically important for evaluating simulations of present climate change. This study examined the long-term trends in PICTL surface air temperature （SAT） in CMIP5 models. Small trends （〈0.06 ℃/100 year） in the globally averaged SAT （GASAT） exist in most CMIP5 models. Of these, positive （negative） trends result from positive （negative） net radiation fluxes at the TOA. This conclusion was further confirmed by the significant positive correlations between the TOA and the SAT tendency. The PICTL GASAT trends constitute less than 10% of the historical trends, indicating that such trends are of negligible importance in estimates of historical global warming in most models. Spatially, relative to the historical trends, the PICTL trends comprise a nontrivial fraction （〉20%） in the Southern Ocean between 50°S and 65°S and in the northern Atlantic and Pacific oceans north of 40°N, with large inter-model spread. The long-term behavior of SAT is significantly related to ocean circulation adjustment in the mid-high latitudes.

关键词： Climate drift CMIP5 historical warming trend

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