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| 1 | Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China显示文摘Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas of northern China showed that pollen concentrations reflect the intensities of human impact to some degree. For example, pollen concentrations decrease as human impacts increase in intensity. The cereal pollen proportions in farmland differed by area. In Northeast China, cereal pollen proportions were distinctly higher than in most other areas of northern China, suggesting differences in planting habits and climate. | LI ManYue LI YueCong XU QingHai PANG RuiMing DING Wei ZHANG ShengRui HE ZhiGuo | 2012 | Chinese Science Bulletin2012，57，5： | 10 |
| 2 | Surface pollen assemblages as indicators of human impact in the warm temperate hilly areas of eastern China显示文摘Investigation of 78 surface pollen samples from warm temperate hilly areas of eastern China shows that pollen assemblages in areas of different land use are significantly different.Pollen concentrations in wastelands are higher than in plantations;these,in turn,are higher than in farmlands;implying that pollen concentration decreases with increasing human impact.Arboreal pollen dominated by Pinus and Quercus is common in all samples.Herbaceous pollen percentages are higher while shrub pollen,fern spores and fern allies are lower in farmlands than in wastelands.Crop pollen is only detectable in and near farmlands;its percentages and concentrations decrease in wastelands.Cereal and Cruciferae pollen percentages average 16.7% and 6.7% in farmland respectively,but Cereal reduces to less than 3% and Cruciferae to less than 0.5% in nearby wastelands.Principle coordinates analysis and clustering analysis indicate that pollen assemblages from farmlands are distinguishable from those under other vegetation types.Occurrence of Poaceae,Chenopodiaceae,Artemisia,and Compositae pollen and Selaginella sinensis spores are closely related to human activities,and their types and frequencies indicate intensity of human impact.The spatial distribution of crops,Chenopodiaceae,and Artemisia reflects changes in both natural environments and human activities.Percentages of cereal and Cruciferae pollen,for example,increase with decreasing altitude,but decrease with increasing latitude.Understanding pollen assemblages under artificial and human-disturbed vegetation in hilly areas may aid understanding of human impacts on the plains during the early-middle Holocene. | DING Wei PANG RuiMing XU QingHai LI YueCong CAO XianYong | 2011 | Chinese Science Bulletin2011，56，10： | 6 |
| 3 | Pollen assemblages of cultivated vegetation in central and southern Hebei Province显示文摘从在 Hebei 省的中央、南部的部分的栽培植被的不同类型的 82 件表面土壤花粉样品上的学习显示从在平原的农田的花粉集合从附近的山有不仅他们的自己的工厂类型,而且花粉部件。树木的花粉百分比和集中(由 Pinus 统治了) 从在山区的农田比在平原的那些高,并且它与增加的距离逐渐地减少离开山。作为一个例子在 Taihang 山拿 Pinus 花粉,它的内容是 20%30% , 10%20% , 20%30% 并且低于 16% 分别地为来自离开东方 Taihang 山的 050, 50100, 100150 和超过 150 km 的区域的样品。在中央平原的 Pinus 花粉比例的增加可能与 fohn 效果有关。到在 Hebei 省的平原的从山的 AP 的空间变化可能类似于由在早历史的时期的人的活动的森林清理。灌木状的花粉比例在山并且在平原是小的,但是他们的主要部件是不同的。Elaeagnaceae, Corylus, Ostryopsis 和 Oleaceae 在山区是普通的,当在平原有 Rosaceae 和 Vitaceae 的相对高的内容时。在平原(大约 60%) 的植物内容在山,谷物和十字花科花粉百分比分别地更高在之中是 5% 和 2% 比那高是 15% 。在平原的 Artemisia 花粉百分比在山是比那低的。因为人的活动在平原与那相比在山是更弱的,一般趋势是 Chenopodiaceae 花粉逐渐地从山增加到平原,反映人的活动的涨的紧张。在山的 Selaginella sinensis 的蕨纲植物孢子在平原比那高,但是它仍然在平原到达到大约 7% 。Selaginella sinensis 的蕨纲植物孢子不是容易的被风散布,显示那些可以被从在平原的免职期间的山的河水在平原的表面土壤带。 | PANG Ruiming | 2011 | Journal of Geographical Sciences2011，21，3： | 1 |
| 4 | Correlation between aortic/carotid atherosclerotic plaques and cerebralinfarction显示文摘 | Baojun Wang Shaoli Sun Guorong Liu Yuechun Li Jiangxia Pang Jingfen Zhang Lijuan Yang Ruiming Li Hui Zhang Changchun Jiang Xiue Li | 2013 | Experimental and Therapeutic Medicine2013，，2： | 1 |
| 5 | Overcoming power efficiency limitation of white fluorescence light-emitting diodes via multilevel-hydrogen-bond matrix显示文摘High power efficiency and low efficiency roll-off at practical luminance are two requirements for new-generation energy-saving lighting technologies,which are still bottlenecks of thermally activated delayed fluorescence(TADF)white organic light-emitting diodes(WOLED),despite the advantages of TADF materials and devices in low cost and high sustainability.Herein,we developed a spiro phosphine oxide host named SSOXSPO,which can form multiple and multidirectional intermolecular hydrogen bonds(IHB).The resulted multilevel IHB network integrates long-range ordered and short-range disordered alignments for suppressing triplet-polaron quenching(TPQ)and triplet-triplet annihilation(TTA).Electronic characteristics of SSOXSPO matrix are further regulated,leading to the optimal exciton allocation through balancing energy and charge transfer.As consequence,using SSOXSPO as host,the single-emissive-layer TADF WOLEDs realized the record performance,including ultralow operation voltage as∼4.0 V,power efficiency beyond fluorescent tube(70.1 lm W−1)and negligible external quantum efficiency roll-off(3%)at 1000 nits for indoor lighting.This work demonstrates that multiple interplays supported by host matrixes in TADF WOLEDs can facilitate the synergistic effects of TADF emitters on 100%exciton utilization. | Ruiming Du Peng Ma Yi Man Yudong Pang Chunbo Duan Chunmiao Han Jing Zhang Chenhui Cao Ying Wei Xinfeng Shui Hui Xu | 2023 | Aggregate2023，4，6： | 0 |
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