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Synthesis, Single-crystal Structure and Fluorescence Property of a New Boron Compound Based on 2-(2'-hydroxyphenyl)-1H-benzimidazole

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Chinese Journal of Structural Chemistry 2018年第12期37卷 1994-2002,1847页

作者：尹国杰楚希杰张涛毛海舫王朝阳阳勇福 School of environmental Engineering and Chemistry Luoyang Institute of Science and Technology School of Chemical and environmental Engineering Shanghai Institute of Technology School of Materials science and Engineering Luoyang Institute of Science and Technology

A new boron compound [C27H21BN4O3] based on 2-(2?-hydroxyphenyl)-1 Hbenzimidazole has been synthesized and characterized by single-crystal X-ray diffraction, and its crystal crystallizes in the monoclinic system, space group P21/n with a = 9.6544(5), b = 14.1558(8), c = 16.4314(9) ?, β = 97.730°, Mr = 460.29, V = 2225.2(2) ?~3, Z = 4, Dc = 1.374 g/cm~3, μ = 0.74 mm-1, S = 1.051, F(000) = 960, the final R = 0.0643 and w R = 0.1569 for 2233 observed reflections(I > 2σ(I)). The title compound is a B(III) center mononuclear molecule in the asymmetric unit. The typical structural characteristic of the title compound is the methanol group adopting a μ2-bridging mode to link two different adjacent chelating modes though two types of hydrogen bonds to form a one-dimensional supramolecular structure. Additionally, aromatic π-π stacking interactions between adjacent benzimidazolyl groups lead to a three-dimensional network. Furthermore, the stability and fluorescence property revealed the potential applications in the organic photoelectric material.

关键词： synthesis crystal structure stability fluorescence property

Analysis of erosion rill development under rainfall events using structure-from-motion photogrammetry——a case study from Kielce(Holy Cross Mts.,Poland)

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Journal of Mountain science 2022年第5期19卷 1231-1244页

作者： Piotr Tomasz KOPYSC Jan Kochanowski University Institute of Geography and Environmental SciencesUniwersytecka 725-406 KielcePoland

The development of erosive landforms such as rills,ditches,slits,and gullies depends on many environmental factors;thus,the rate of the development of each individual form *** this paper,the author presents a case study of two erosion rills located on a hiking trails(Holy Cross Mts.)resulting after 2 years of monitoring in which the process of their evolution was precisely *** established,such landforms develop over time with variable rates and can represent multiple different ***,the final result of the rill development hardly reminds their original form and does not allow for interpretation of the events that affected it in the recent ***,the main objective was to determine the volumetric changes of erosion rills created by the surface runoff on both sections,during two years of *** objectives included a description of the physical and meteorological parameters,important in the development process and a comparison of them to the volumetric changes of each *** the Structure-from-motion(Sf M)photogrammetry technique,monitoring procedures have been performed quickly offering sufficient *** direct comparison,the digital elevation model of difference(Do D)method was used,enabling the calculation of *** results showed that the erosion to deposition ratio was more disproportionate during storm events or periods with higher depth of *** erosion to deposition balance for the entire monitoring period was negative and equal to 1448.84 kg or 410 Mg/ha for the first erosion rill and 1059.5 kg or 300 Mg/ha for the second *** erosion rills developed *** first erosion rill developed by linear cut into deeper and wider form,while the other,steeper rill,evolved from plunge pools merging together into deeper and wider form.

关键词： Erosion SfM DoD Rainfall Microtopography

Debromination of decabromodiphenyl ether by organo-montmorillonitesupported nanoscale zero-valent iron: Preparation, characterization and influence factors

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Journal of environmental sciences 2014年第2期26卷 483-491页

作者： Zhihua Pang Mengyue Yan Xiaoshan Jia Zhenxing Wang Jianyu Chen School of environmental science and Engineering Sun Yat-Sen University South China institute of environmental sciences Ministry of Environmental Protection

An organo-montmorillonite-supported nanoscale zero-valent iron material （M-NZVI） was synthesized to degrade decabromodiphenyl ether （BDE-209）. The results showed that nanoscale zero-valent iron had good dispersion on organo-montmoriUonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30-90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased.

关键词： supported nanoscale zero-valent iron organo-montmorillonite decabromodiphenyl ether (BDE-209) degradation influence factors

Progress of applied research on TiO_2 photocatalysis-membrane separation coupling technology in water and wastewater treatments

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Chinese science Bulletin 2010年第14期55卷 1345-1353页

作者： XIAO YuTang XU ShuangShuang LI ZhiHua AN XiaoHong ZHOU Lei ZHANG YongLai FU Q. Shiang School of environmental science & Engineering Nankai University Tianjin 300071 China Nanjing institute of geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

Photocatalysis-membrane separation coupling technology has been a heavily researched area in water and wastewater treatment during recent years. The membrane separation process allows the photocatalyst to be easily separated, recovered and reused. More significantly, the membrane is efficient to maintain high flux of membranes as the photocatalyst can reduce the membrane fouling problem which is a hindrance in the development of membrane process. Moreover, some synergistic effects can also be produced, and thus the efficiency of water treatment is enhanced greatly. A comprehensive review of photocatalysis-membrane separation coupling technology is conducted with an insight into its configurations, theories involved, characteristics, and factors that influ-ence the coupling technology. In view of the existing problems, the prospects for future development are also proposed.

关键词：光催化膜耦合技术废水处理分离水二氧化钛膜分离过程应用污水处理

High-resolution stalagmite δ13C record of soil processes from southwestern China during the early MIS 3

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Chinese science Bulletin 2013年第7期58卷 796-802页

作者： LIU DianBing WANG YongJin CHENG Hai EDWARDS R L College of geography science Nanjing Normal University institute of Global environmental Change Xi'an Jiaotong University Department of Geology and Geophysics University of MinnesotaMinneapolis

Knowledge of the evolution of pedogenic processes in the carbonate area is important to understand the dynamics of rock desertification.A precisely-dated stalagmite δ13C record between 61.3 and 50.5 ka BP from southwestern China,potentially related to soil biogenic CO2 production,shifts within a narrow range between -9‰ and -7‰,and exhibits a prominent cycle of 350-470 a,independent of the Asian monsoon *** indicates that a threshold effect might control the amplitude of calcite δ13C variability,likely associated with the vertical soil loss in the carbonate *** periodic δ13C changes reflect that the loss/recovery of soil cover can operate on centennial ***,the rock desertification in southwestern China might at least initiate 60 ka ago and should be of natural origin.

关键词： Wulu 洞石笋稳定的碳同位素一百年的变化玷污过程

An analytical model for bidirectional reflectance factor of multicomponent vegetation canopies

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science China(Life sciences) 1997年第3期40卷 305-315页

作者：覃文汉项月琴 Station for Agroecolugy and environmental Technology Institute of Geography Chinese Academy of Sciences Beijing 100101 China

Based on radiative transfer theory in vegetation and geometric-optical principles, an analytical physi-cal mode] for calculating multiangular, multispectral reflectance over a non-random, multiple component vegetation canopy is developed. This model is derived by taking advantages of the previous leaf canopy and multicomponent canopy BRF models. It quantitatively accounts for both the impact of foliage elements' orientation on the canopy hotspot through an innovative algorithm to estimate the hotspot function for any arbitrarily oriented foliage element and contributions of all foliage elements to the reflectance by multiple scattering. Thus, it is characterized by more com-pletely considering the integrative influence of spatial variations in optical and structural properties of all foliage ele-ments on canopy reflectance than any previous analytical BRF models. Simulation results from this model demonstrate that canopy hotspot becomes strongest when the mean inclination angle of foliage elements is around 20? and then it rapidly decreases with an increase in that angle. Comparison with field measured BRF data shows that this model can reproduce the angular asymmetrical distribution of canopy BRF, a feature of natural vegetation's reflectance which all leaf canopy models cannot reproduce.

关键词： multi-angle remote sensing BRDF model radiative transfer in vegetation hotspot effect.

The higher grain production, the more social deprivation? A case study of Henan province in traditional agricultural areas of China

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Journal of Mountain science 2018年第1期15卷 167-180页

作者： GAO Jun-bo QIAO Wei-feng LIU Yan-sui LI Yu-rui TU Wei ZHANG Yong-xian institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences School of geography science Xinyang Normal University School of geography science Nanjing Normal University Department of Geology & geography Georgia Southern University institute of Surveying And Mapping Information Engineering University

This paper examines the spatial-temporal dynamics of inequality from the perspective of social deprivation in the context of continuous growth of grain production using national census data from 2000 and 2010 for Henan province,*** analytical results show an overall level of social deprivation that is high and a widening social deprivation gap at the county *** social deprivation shows great spatiotemporal heterogeneity,the higher deprived counties are mainly distributed in central and eastern Henan province,while counties with lower social deprivation are clustered in northwestern regions,formed a belt-shape spatial differential between the south(higher deprived counties clustered)and northwest(low deprived counties clustered)Henan in 2000,and changed toward a core-periphery semi annular spatial structure in 2010,the low deprived counties surrounded by high deprived *** social deprivation shows a"west low and east high"spatial pattern,similar to the grain production in Henan *** development level was low in most counties in Yudong plain despite of keeping the continuous increase of grain production,meaning the higher grain output did not result in the more social development expected in Chinese traditional agricultural areas,and the regional disparity is expected to increase in the near future if development conditions are not changed,which could inspire more targeted rural governance options.

关键词： Spatial-temporal change Grain production Social inequality Social deprivation Henan province

Membrane fouling characteristics analysis of high concentration powdered activated carbon-microfiltration integrated system

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Journal of Harbin institute of Technology(New Series) 2010年第3期17卷 345-350页

作者：严晓菊于水利杨旭时文歆安延涛 School of Municipal and environmental Engineering Harbin Institute of Technology School of geography Harbin Normal University

The membrane fouling characteristics of high concentration powdered activated carbon-microfiltration (HCPAC-MF) integrated process are studied by comparing them with those of direct microfitration system using the particle counter,scanning electron microscope (SEM) and atomic force microscope (AFM). The results indicate that the specific flux of HCPAC-MF is 3 times better than that of the direct filtration process after the system is stabilized. The addition of HCPAC changes the particle distribution of raw water and influences the structure of surface fouling layer. The PAC with irregular shapes aggregating on the membrane surface makes the cake layer structure loose and increases the roughness of membrane surface,and this decreases the thickness of hydrodynamic boundary layer and the membrane resistance. After the physical cleaning,the membrane surface and pores are clean without any fouling matters aggregation,which illustrates that the cake layer of PAC can be formed quickly in this HCPAC environment and prevent the occurrence of irreversible fouling.

关键词： PAC MF membrane fouling SEM AFM

An IconMap-based exploratory analytical approach for multivariate geospatial data

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science China(Information sciences) 2013年第1期56卷 198-207页

作者： ZHANG XianFeng LIAO ChunHua LIU Yu LI Jonathan institute of Remote Sensing and GIS Peking University Department of geography and environmental Management University of Waterloo

This paper discusses an iconmap-based visualization technique that enables multiple geospatial variables to be illustrated in a single GIS raster *** is achieved by extending the conventional pixelbased data structure to an iconic *** this way,spatial patterns generated by the interaction of geographic variables can be disclosed,and geospatial information mining can be readily *** a case study,a visual analysis of soil organic matter and soil nutrients for Shuangliu County in the city of Chengdu,China,was undertaken using the prototype IconMapper software,developed by the *** results show that the static IconMap can accurately exhibit trends in the distribution of organic matter and nutrients in *** dynamic iconmap can both reflect interaction patterns between organic matter and the nutrient variables,and display soil fertility levels in a comprehensive ***,the iconmap-based visualization approach is shown to be a non-fused,exploratory analytical approach for multivariate data analysis and as a result is a valuable method for visually analyzing soil fertility conditions.

关键词： iconmap soil fertility visualization icon blocks multivariate geospatial data