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Exogenous Nitric Oxide Alleviated the Inhibition of Photosynthesis and Antioxidant Enzyme Activities in Iron-Deficient Chinese Cabbage (Brassica chinensis L.)

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Agricultural Sciences in China 2008年第2期7卷 168-179页

作者： DING Fei wang Xiu-feng SHI qing-hua wang Mei-ling YANG feng-juan GAO qing-hai State Key Laboratory of Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R. China

The effects of exogenous nitric oxide （NO） on plant growth, chlorophyll contents, photosynthetic and chlorophyll fluorescence parameters as well as lipid peroxidation and activities of antioxidant enzymes were investigated in Chinese cabbage plants exposed to iron （Fe） deficiency. Iron deficiency led to serious chlorosis in Chinese cabbage leaves, and resulted in significant decrease in plant growth, photosynthetic pigments, net photosynthetic rate, Fv/Fm, Ф ps Ⅱ and activities of antioxidant enzymes, and increase in lipid peroxidation. While treatment with SNP, a NO donor, it could revert the iron deficiency symptoms, increased photosynthetic rate as well as activities of antioxidant enzymes, and protected membrane from lipid peroxidation, as a result, the growth inhibition of Chinese cabbage by Fe deficiency was alleviated.

关键词： antioxidant enzyme Chinese cabbage iron deficiency nitric oxide photosynthesis

Pollinator diversity benefits natural and agricultural ecosystems,environmental health,and human welfare

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Plant Diversity 2022年第5期44卷 429-435页

作者： Daniel Mutavi Katumo Huan Liang Anne Christine Ochola Min Lv qing-feng wang Chun-feng Yang CAS Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesWuhan 430074China

Biodiversity loss during the Anthropocene is a serious ecological *** are important vectors that provide multiple essential ecosystem services but are declining rapidly in this changing ***,several studies have argued that a high abundance of managed bee pollinators,such as honeybees(Apis mellifera),may be sufficient to provide pollination services for crop productivity,and sociological studies indicate that the majority of farmers worldwide do not recognize the contribution of wild pollinator diversity to agricultural ***,we review the importance of pollinator diversity in natural and agricultural ecosystems that may be thwarted by the increase in abundance of managed pollinators such as *** also emphasize the additional roles diverse pollinator communities play in environmental safety,culture,and *** indicates that in natural ecosystems,pollinator diversity enhances pollination during environmental and climatic perturbations,thus alleviating pollen *** agricultural ecosystems,pollinator diversity increases the quality and quantity of crop ***,studies indicate that many pollinator groups are useful in monitoring environmental pollution,aid in pest and disease control,and provide cultural and aesthetic *** the uncertainties that may accompany rapid environmental changes in the Anthropocene,the conservation of pollinator diversity must expand beyond bee ***,the value of pollinator diversity maintenance extends beyond the provision of pollination ***,conservation of pollinator diversity requires an interdisciplinary approach with contributions from environmentalists,taxonomists,and social scientists,including artists,who can shape opinions and behavior.

关键词： Bee Complementarity Ecological indicator Plant community Pollen limitation

The synthesis and spectroscopic investigation of vinylated meso-tetraphenylporphyrin

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Chinese Chemical Letters 2007年第11期18卷 1319-1322页

作者： Jin Qiang Xue Ya qing feng Lei wang Ling Hui Wu School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

A series of new vinylated 5,10,15,20-tetraphenylporphyrins have been synthesized and characterized by ^1H NMR, MS, UV-vis and fluorescence studies. Following selective excitation of the porphyrin compounds with UV light, the energy is transferred to the porphyrin core and reemitted as red light. In Comparison to tetraphenylporphyrin （TPP）, the luminescence properties are markedly improved.

关键词： Porphyrin Spectrum Vinylated Luminescence

Non-climate environmental factors matter to Holocene dynamics of soil organic carbon and nitrogen in an alpine permafrost wetland,qinghai‒Tibet Plateau

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Advances in Climate Change Research 2023年第2期14卷 213-225页

作者： qing-feng wang Hui-Jun JIN Cui-Cui MU Xiao-Dong WU Lin ZHAO qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Civil Engineering Northeast China Observatory and Research Station of Permafrost Geo-Environment(Ministry of Education)Institute of ColdRegions Engineering and EnvironmentNortheast Forestry UniversityHarbin 150040China Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesObservation and Research Station on Eco-Environment of Frozen Ground in the Qilian MountainsLanzhou UniversityLanzhou 730000China Cryosphere Research Station on the qinghai‒Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 101408China School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China

Studies on the responses of soil organic carbon(SOC)and nitrogen dynamics to Holocene climate and environment in permafrost peatlands and/or wetlands might serve as analogues for future scenarios,and they can help predict the fate of the frozen SOC and nitrogen under a warming *** date,little is known about these issues on the qinghai‒Tibet Plateau(QTP).Here,we investigated the accumulations of SOC and nitrogen in a permafrost wetland on the northeastern QTP,and analyzed their links with Holocene climatic and environmental *** order to do so,we studied grain size,soil organic matter,SOC,and nitrogen contents,bulk density,geochemical parameters,and the accelerator mass spectrometry(AMS)^(14)C dating of the 216-cm-deep wetland *** and nitrogen contents revealed a general uptrend over last 7300 *** stocks for depths of 0-100 and 0-200 cm were 50.1 and 79.0 kgC m^(-2),respectively,and nitrogen stocks for the same depths were 4.3 and 6.6 kgN m^(-2),***,a cooling and drying trend for regional climate over last 7300 years was inferred from the declining chemical weathering and humidity ***,SOC and nitrogen accumulated rapidly in 1110e720 BP,while apparent accumulation rates of SOC and nitrogen were much lower during the other periods of the last 7300 ***,we proposed a probable conceptual framework for the concordant development of syngenetic permafrost and SOC and nitrogen accumulations in alpine permafrost *** indicates that,apart from controls of climate,non-climate environmental factors,such as dust deposition and site hydrology,matter to SOC and nitrogen accumulations in permafrost *** emphasized that environmental changes driven by climate change have important impacts on SOC and nitrogen accumulations in alpine permafrost *** study could provide data support for regional and global estimates of SOC and nitrogen pools and for global models on carbon‒climate interactions

关键词： Syngenetic permafrost in alpine wetland Soil organic carbon pool Nitrogen accumulation Chemical weathering Dust deposition Holocene

Effect of welding heat input on microstructure and impact toughness in CGHAZ of X100Q steel

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Journal of Iron and Steel Research International 2019年第6期26卷 637-646页

作者： Hui-bin wang Fei-long wang Gen-hao Shi Yu Sun Jiang-cheng Liu qing-feng wang Fu-cheng Zhang State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004. Hebei China Technical Center Tianjin Pipe (Group) Co. Ltd. Tianjin 300301 China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University Qinhuangdao 066004 Hebei China

The coarse-grained heat-affected zones (CGHAZs) of X100Q steel were reproduced via simulating their welding thermal cycles with the varying heat input (Ef) from 10 to 55 kJ/cm in Gleeble3500 system. The microstructures were characterized, and the impact toughness was estimated from each simulated sample. The results indicate that the microstructure in each simulated CGHAZ was primarily constituted of lath-like bainite. With the decreased heat input and accordingly the lowered Ar3 (the onset temperature for this transition), the prior austenite grain and the bainitic packet/block/lath substructure were refined remarkably, and the impact toughness was enhanced due to the microstructure refinement. The bainitic packet was the microstructural unit most effectively controlling the impact properties in CGHAZ of X100Q steel, due to their close correlation with the 50% fracture appearance transition temperatures, their size equivalent to the cleavage facet and their boundaries impeding the crack propagation.

关键词： X100Q bainitic steel Coarse-grained heat-affected zone Impact property Bainitic substructure Fractography

基于强化学习的混合动力挖掘机实时能量管理控制器设计（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第11期18卷 855-870页

作者： Qian ZHU qing-feng wang State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

目的:混合动力挖掘机的能量管理策略直接影响着系统的燃油经济性。本文旨在通过研究混合动力挖掘机能量管理系统,得到最优能量管理策略,并开发实时能量管理控制器,降低系统的燃油消耗。创新点:1.通过强化学习算法,设计时间无关的实时能... 详细信息

目的:混合动力挖掘机的能量管理策略直接影响着系统的燃油经济性。本文旨在通过研究混合动力挖掘机能量管理系统,得到最优能量管理策略,并开发实时能量管理控制器,降低系统的燃油消耗。创新点:1.通过强化学习算法,设计时间无关的实时能量管理控制器;2.通过极大值原理求得最优能量管理问题的解析解,并用来辅助实时能量管理控制器设计。方法:1.建立负载的马尔科夫模型,运用强化学习算法,得到实时能量管理控制器;2.运用极大值原理,求得最优能量管理问题的解析解,并将其作为初始能量管理策略;3.通过仿真模拟和实验研究,验证所设计的实时能量控制器的性能。结论:1.基于强化学习的能量管理控制器是一个可以在线应用的与时间无关的实时能量管理控制器;2.基于强化学习的能量管理控制器优于广泛使用的恒温控制器和等效消耗最小化策略控制器;3.基于强化学习的能量管理控制器由于其闭环特性可适用于不同类型的作业工况。

关键词：能量管理实时性混合动力挖掘机强化学习极大值原理

Geographic patterns of taxonomic and phylogenetic β-diversity of aquatic angiosperms in China

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Plant Diversity 2023年第2期45卷 177-184页

作者： Ya-Dong Zhou Hong Qian Yi Jin Ke-Yan Xiao Xue Yan qing-feng wang School of Life Sciences Nanchang UniversityNanchang 330031JiangxiChina Research and Collections Center Illinois State MuseumSpringfieldIllinoisUSA Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang550025China Wuhan Botanical Garden/Core Botanical Gardens Chinese Academy of SciencesWuhan 430074HubeiChina Sino-Africa Joint Research Center(SAJOREC) Chinese Academy of SciencesWuhan 430074HubeiChina

China covers a vast territory harbouring a large number of aquatic *** there are many studies on the β-diversity of total,herbaceous or woody plants in China and elsewhere,few studies have focused on aquatic ***,we analyse a comprehensive data set of 889 aquatic angiosperm species in China,and explore the geographic patterns and climatic correlates of total taxonomic and phylogeneticβ-diversity as well as their turnover and nestedness *** results show that geographic patterns of taxonomic and phylogenetic β-diversity are highly congruent for aquatic angiosperms,and taxonomic β-diversity is consistently higher than phylogenetic β-*** ratio between the nestedness component and total β-diversity is high in northwestern China and low in southeastern *** geographic patterns of taxonomic and phylogenetic β-diversity of aquatic angiosperms in China are obviously affected by geographic and climatic distances,*** conclusion,the geographic patterns of taxonomic and phylogenetic β-diversity of aquatic angiosperms are consistent across *** and geographic distances jointly affect the geographic patterns of β-diversity of aquatic ***,our work provides insight into understanding the large-scale patterns of aquatic angiosperm β-diversity,and is a critical addition to previous studies on the macroecological patterns of terrestrial organisms.

关键词： Freshwater plants β-diversity Phylogenetic metric Geographic pattern Climate

Phylogeography of Haplocarpha rueppelii(Asteraceae) suggests a potential geographic barrier for plant dispersal and gene flow in East Africa

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Science Bulletin 2015年第13期60卷 1184-1192页

作者： Ling-Yun Chen John K.Muchuku Xue Yan Guang-Wan Hu qing-feng wang Sino-Africa Joint Research Center Chinese Academy of Sciences Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden Chinese Academy of Sciences University of Chinese Academy of Sciences

East Africa is a biodiversity hotspot. Haplocarpha rueppelii （***.） Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation （intrinsic reproductive isolation and geographic barrier）. The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists＇ interests in phylogeography and biodiversity of East Africa.

关键词： East Africa . Afro-alpine . Gene flow .Phylogeography . Taxonomy . Haplocarpha rueppelii

Effect of increased nitrogen content on continuous cooling transition of γ→α in hot-deformed low-C Mo-V-Ti steels

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Journal of Iron and Steel Research International 2019年第7期26卷 733-742页

作者： Xin-ping Xiao Gen-hao Shi Shu-ming Zhang Yu-wei Gao qing-feng wang Fu-cheng Zhang State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 Hebei China Qinhuangdao Vocational and Technical College Qinhuangdao 066100 Hebei China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University Qinhuangdao 066004 Hebei China

The two-stage controlled rolling and cooling at 0.5-50℃/s of low-carbon Mo-V-Ti steels with the increasing nitrogen content from 0.0032 to 0.0081 and 0.0123 wt.% were simulated through a Gleeble 3500 system. The continuous cooling transition (CCT) of γ→α in each steel was estimated via microstructure characterization and CCT diagram. The results indicated that CCT diagram for each steel was divided into three regions of γ→ferrite,γ→pearlite and γ→ bainite, and the increasing N content elevated all the starting temperatures for γ→α. Consequently, the polygonal ferrite (PF) and pearlite formed in each steel cooled at 1℃/s and, however, the increasing N content led to slightly coarser ferrite grain and pearlite colony. With the increased cooling rate to 10 and 30℃/s, a mixed microstructure of acicular ferrite (AF), granular bainite (GB) and lath bainite (LB) formed in 32N steel and in contrast, the mixture of PF+AF+GB in 8IN and 123N steels. The increasing N content promoted (Ti,V)(C,N) precipitation, enhanced the intragranular PF/AF nucleation, increased martensite/austenite constituent and depressed LB. In addition, the mechanisms dominating the effect of increasing N on this CCT of γ→α were discussed.

关键词： V-N microalloyed steel Continuous cooling transition Microstructure Precipitation Intragranular ferrite