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Dye removal by eco-friendly physically cross-linked double network polymer hydrogel beads and their functionalized composites

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Journal of Environmental Sciences 2019年第4期31卷 81-91页

作者： Yan Kong Yuan Zhuang zhiyong han Jianwei Yu Baoyou Shi Kun han Haotian Hao Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences College of Petrochemical Engineering Lanzhou University of Technology University of Chinese Academy of Sciences

Hydrogels have attracted large attention in wastewater treatment fields due to their low-cost and good interaction with pollutants,among which novel double network hydrogel is an outstanding *** expand the application of double network hydrogel in water treatment,in this study,eco-friendly physically cross-linked double network polymer hydrogel beads(DAP)are prepared and studied in depth on the mechanism of Methylene Blue(MB)adsorption;and then the polymer hydrogels are further functionalized by inorganic *** adsorption on DAP favors alkaline condition which is due to the increase of electrostatic attraction and adsorption site,and it reaches equilibrium within 10 hr,which is faster than that of the single network hydrogel beads(SAP).Through thermodynamics study,the process shows to be an exothermic and spontaneous *** adsorption isotherms are well fitted by Langmuir model,with a maximum monolayer adsorption capacity of 1437.48 mg/g,which is larger than SAP(1255.75 mg/g).After being functionalized with common inorganic materials including activated carbon,Fe_3O_4and graphene oxide(GO),the composites show to have larger pore sizes and have obvious increases in adsorption capacity especially the one contains *** the composites contains Fe_3O_4are used as heterogeneous Fenton catalyst which shows to have excellent performance in MB *** results indicate the potential of polymer double network to be functionalized in environmental areas.

关键词： Adsorption Alginate Poly(vinyl alcohol) Hydrogel Methylene Blue

Diverse Climatic and Anthropogenic Impacts on Desertification in the Middle Reaches of Yarlung Zangbo River Catchment on the Tibetan Plateau

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Journal of Earth Science 2023年第6期34卷 1816-1826页

作者： Qi Yu Xianyan Wang zhiyong han Xiaodong Miao Huayu Lu School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Xining810016China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection School of Resource and Environmental SciencesLinyi UniversityLinyi 276000China

The unique desertification processes occurring under the Alpine climate and ecosystem on the Tibetan Plateau could provide critical clues to the natural and anthropogenic impacts on *** study used the Landsat data to investigate the spatial and temporal distribution of desertification from 1990 to 2020 in two areas(Shannan and Mainling),within the Yarlung Zangbo River *** results show not only distinct spatial patterns but also various temporal changes of *** Shannan,aeolian sand was distributed over wide areas from valley floor to mountain slope,while in Mainling,it is distributed sporadically at the *** aeolian sandy land initially expanded before undergoing long-term shrinkage in *** in Mainling,it steadily expanded followed by a rapid *** changes are attributed to both climate change and human *** increase in temperature causes desertification expansion in Shannan,while favorable climate conditions coupled with decreasing human activity promoted desertification ***,both the expansion and shrinkage of desertification were sensitive to human activity in *** highlights the diverse responses of desertification to natural and anthropogenic impacts on different backgrounds of climatic and vegetation coverage.A threshold of climatic conditions may control the dominance factors in desertification,shifting from natural to anthropogenic elements.

关键词： desertification reversal of desertification human activities climate change remote sensing Yarlung Zangbo River valley

Tectonically-controlled infilling of the eastern Nihewan Basin,North China,since the middle Pleistocene

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Science China Earth Sciences 2016年第7期59卷 1378-1389页

作者： han zhiyong LI XuSheng WANG Yong WANG XianYan YI ShuangWen LU HuaYu School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

There has been a significant debate about the nature and causes of the Pleistocene evolution of the Nihewan Basin, North China. We studied the eastern Nihewan Basin sedimentary facies at two main sites, Hutouliang and Donggou. A combination of field observations and measurements of sediment grain-size distribution was used to reconstruct the sequence of sedimentary environments since the middle Pleistocene, and optically-stimulated luminescence measurements were used to date the sediments. Our results indicate that a shallow lake occupied the basin center along the Sanggan River, probably lasting until -440 kyr ago before disappearing completely -340 kyr ago. It was succeeded by a phase of fluvial-dominated sediment accumulation which ended -30 kyr ago. We suggest that the formation of the gorge resulted from the relative uplift of the Niuxin Mountain along the Liulengshan fault -140 kyr ago. However, since -30 kyr ago the fault may have become inactive and the river downcutting near Shixia was no longer offset by the relative uplift, which caused a shift from deposition to denudation in the Nihewan Basin from then on. The disappearance of the paleolake -340 kyr ago may have been the culmination of the ongoing process of basin infilling.

关键词： Nihewan Basin Sedimentary facies Paleolake Fault OSL

Application of River Longitudinal Profile Morphometrics to Reveal the Uplift of Lushan Mountain

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Acta Geologica Sinica(English Edition) 2017年第5期91卷 1644-1652页

作者： han zhiyong LI Xusheng WANG Nairui CHEN Gang WANG Xianyan LU Huayu School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China Nanjing Hydraulic Research Institute Nanjing 210029 China

The stream power model was applied to Lushan Mt. in South China in order to verify its capability of interpreting the uplift of a small block mountain. On a log-log plot, the longitudinal profiles of 9 rivers derived from a 30 m DEM exhibit primary characteristics similar to those derived from a 5 m DEM; however, the 5 m DEM clearly reveals more minor knickpoints, and the positions of knickpoints are pinpointed more accurately. All of the studied rivers on the block mountain are in a transient state due to geological perturbations. Some of them exhibit two segments in steady state separated by a slopebreak knickpoint. Such rivers generally develop in a longitudinal valley, which are less perturbed by substrate inhomogeneities. The similar heights of the slope-break knickpoints and the similar uplift rate indicated by the k_（sn） values demonstrate an almost simultaneous headward erosion induced by the fall in base level. This modelling result is consistent with the mode of formation of this particular block mountain. Our study demonstrates that the stream power model is applicable to a small tectonicallyactive massif only if the channel segments are in a steady state.

关键词： knickpoint river longitudinal profile normalized steepness index uplift rate

Onset of Xiashu loess deposition in southern China by 0.9 Ma and its implications for regional aridification

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Science China Earth Sciences 2018年第3期61卷 256-269页

作者： Xusheng LI zhiyong han Huayu LU Yingyong CHEN Yang LI Xiaokang YUAN Yuwen ZHOU Mengyao JIANG Cunjuan LV School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210023 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China College of Environment and Planning Henan University Kaifeng 475001

The Xiashu loess is a typical Quaternary eolian deposit in southem China and represents an important terrestrial paleoclimate archive in this low-latitude monsoon region. However, the chronological framework of Xiashu loess deposition has yet to be established. Determining the timing of the onset of Xiashu loess deposition will allow researchers to better understand late Quaternary aridification across the Asian continent, the evolution of the East Asian monsoon and regional environmental changes in subtropical regions. Therefore, in this study, a systematic chronological study of the Xiashu loess is conducted to answer this question. For the first time, magnetostratigraphic classification reveals that the Matuyama/Bnmhes （M/B） reversal is present in the Xiashu loess at two sites in Jiangsu Province, the Qingshan profile at Yizheng and the Dagang core in Zhenjiang. Based on the results of magnetostratigraphy and optically stimulated luminescence （OSL） dating, the age of the lower boundary of the Xiashu loess is estimated to be approximately 0.9 Ma. Consequently, this Xiashu loess deposit is the oldest reported to date and is comparable in age to the red soil deposit in Xuancheng, Anhui Province. The onset of Xiashu loess deposition by 0.9 Ma represents the further expansion of arid range in Asia in the late Quaternary in response to significant aridification and winter monsoon strengthening in this subtropical region. We suggest that these climate changes were primarily driven by global cooling and an increase in high-latitude ice volume in the Northern Hemisphere and that the initiation of Xiashu loess accumulation was a regional response of southern China to the 0.9 Ma global cooling event.

关键词： Xiashu loess Chronology Magnetic stratigraphy Aridification East Asian monsoon

The Morphology and Roughness of Aluminized CoCrAlY Coating By HCPEB

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The Morphology and Roughness of Aluminized CoCrAlY Coating B...

Chemical weathering intensity and element migration features of the Xiashu loess profile in Zhenjiang, Jiangsu Province

2015 2nd International Conference on Machinery,Materials Engineering,Chemical Engineering and Biotechnology(MMECEB 2015)

作者： zhiyong han Jian han Tianjin Key Laboratory for Civil Aircraft Airworthiness and Maintenance Civil Aviation University of China

In this paper,CoCrAlY coating was prepared on the substrate,Ni-based super alloy(GH4169),using Air Plasma Spray(APS).After deposition,the coating was irradiated by High Current Pulse Electron Beam(HCPEB) with different number of pulse *** the micro-structure of coating surface,like the morphology and roughness,were characterized by scanning electron microscope(SEM) and 3D optical *** the coating treated with 20 times pulse beam,the roughness is 28.02 μ***,the surface was remelted into a compact appearance with many bulged nodules connected.

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Journal of Geographical Sciences 2008年第3期18卷 341-352页

作者： CHEN Yingyong LI Xusheng han zhiyong YANG Shouye WANG Yongbo YANG Dayuan School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment CAS Xi＇an 710075 China State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

The chemical weathering intensity and element migration features of the Xiashu loess profile in Zhenjiang are studied in this paper.（1）The Xiashu loess profile underwent moderate chemical *** seems that the precipitation is a more important factor than the temperature in controlling the process of the chemical weathering.（2）The major elements such as Si,K,Na,Ca,Mg,Mn and P were migrated and leached,while the elements Fe and Ti were slightly *** migration features of the major elements reveal that the Xiashu loess finished the primary process of chemical weathering characterized by leaching of Ca and Na,and almost reached the secondary process characterized by leaching of *** the elements Sr and Ga,other trace elements such as Th,Ba,Cu,Zn,Co,Ni,Cr and V were *** might be caused by both the biogeochemical process and the adsorption of trace elements by clay mineral and organic materials.（3）The difference of element migration down the Xiashu loess profile reveals that the climate was warm and wet at the early-middle stage of the middle *** the end of the middle Pleistocene,it became dry and *** the early stage of the Late Pleistocene,the paleoclimate became warm and wet *** a whole,the paleoclimate generally became drier and cooler in this region from the beginning of the middle Pleistocene.

关键词： Xiashu loess chemical weathering element migration Zhenjiang

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手性有机小分子和钯联合不对称催化

化学进展 2018年第5期30卷 505-512页

作者：韩志勇龚流柱中国科学技术大学化学与材料科学学院合肥230026

有机小分子和金属联合催化是指用有机小分子和金属等多种催化剂同时或连续活化不同底物、官能团或中间体,从而完成催化反应。该策略可以实现单一催化剂无法完成的反应。根据催化剂活化模式的不同,有机小分子和金属联合催化可以分为协同... 详细信息

有机小分子和金属联合催化是指用有机小分子和金属等多种催化剂同时或连续活化不同底物、官能团或中间体,从而完成催化反应。该策略可以实现单一催化剂无法完成的反应。根据催化剂活化模式的不同,有机小分子和金属联合催化可以分为协同催化、接力催化与连续催化。近年来,随着有机小分子催化的快速发展以及人们对金属和有机催化的理解越来越深入,有机小分子和金属联合催化方面的报道逐年增加,正在发展成为均相不对称催化中受到广泛关注的新兴研究领域。钯配合物是重要的过渡金属催化剂,钯催化在有机合成中具有十分广泛的应用。本文重点总结了钯和手性有机小分子联合不对称催化方面的进展,主要包括手性胺、手性布朗斯特酸以及手性亲核催化剂等有机催化剂与钯联合催化,同时指出了该领域内一些亟待解决的问题,并对未来的发展作了展望。

关键词：手性有机小分子钯催化联合催化不对称催化

Temporal and Spatial Characteristics and Evolution of China’s Inbound Tourism Carbon Footprint

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Journal of Resources and Ecology 2021年第1期12卷 56-67页

作者： han zhiyong LI Tao LIU Ximei Ocean College of Agriculture University of Hebei QinhuangdaoHebei 066003China School of Geographic Science Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Reducing carbon emissions and transitioning to a low-carbon economy are important propositions for human sustainability. Since it is closely related with high carbon emissions, international travel makes a substantial contribution to the global carbon emissions. To comprehensively explore the influence of international travel on carbon emissions and develop a sustainable development plan, this paper studies the temporal and spatial distribution and evolution of the carbon footprint of inbound tourism in China’s 30 provinces between 2007 and 2017. In this study, comprehensive calculations and spatial models are adopted to reveal the temporal and spatial characteristics. The results show that the carbon footprint of inbound tourism in China has been increasing continuously from 2007 to 2017. While the carbon footprint increased by 1.94-fold, from 5.623 million tons to 10.8809 million tons, it presented obvious fluctuations by initially increasing rapidly and then dropping slightly. From the perspective of the contributions of various tourism components on the carbon footprint, transportation and post and telecommunications account for the largest proportions. In the past ten years, the variations in the carbon footprint of inbound tourism in most provinces and cities in China were not very extreme, but maintained a relatively stable state. In the spatial dimension, the carbon footprint of China’s inbound tourism tends to decrease from the southeast to the northwest. The highest coefficient of variation is in Ningxia and the lowest is in Liaoning. Based on these results, recommendations are put forward for sustainable development plans in some major cities and provinces for the future.

关键词： carbon footprint inbound tourism spatial and temporal distribution China