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Analyzing land use characteristics of rural settlements on the urban fringe of Liangjiang New Area, Chongqing, China

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Journal of Mountain Science 2016年第10期13卷 1855-1866页

作者： wang Yi BI Guo-hua YANG qing-yuan wang zhao-lin College of Resources and Environment Southwest University School of Geographical Sciences Southwest University School of Tourism and Land Resource Chongqing Technology and Business University

The objective of this paper is to analyze land use characteristics of rural settlements in urban fringe so as to provide references for optimizing the regional distribution of rural settlements, consolidating rural settlements, and coordinating urban-rural integrated development. The methods of spatial statistical analysis, buffer analysis, Ripley's K function, kernel density analysis based on GIS(Geographic Information System) were used to analyze the characteristics of scale, spatial differentiation and spatial patterns of the rural settlements in Liangjiang New Area in Chongqing Municipality of China. The fractal dimension formula was also developed to reflect fractal feature of the rural settlements. The results show that, the scale of rural settlements in Liangjang New Area takes on distinct characteristics of spatial differentiation along with changes in elevation, gradient, location, geohazards distribution, and the like. The fractal characteristic of rural settlements has obvious regional variations subject to the 6 factors of location in the Liangjiang New Area. Overall, the worse the terrain conditions are, the larger the fractal dimension values become. The better the locationconditions, the larger the fractal dimension values are. The spatial pattern in the township scale presents three kinds of distribution as being aggregated, uniform and random. In contract, the spatial pattern in the plaque scale displays a banding distribution from a general view with several aggregation zones centering on each town center. From the results, we can see that the characteristics of rural settlements in urban fringe are more complicated. For such kind of rural settlements in special regions, in the rural land consolidation more attention should be paid to improve the rural living environments and public services, as well as to promote the harmonious relationship between the urban and rural areas.

关键词： Land use Rural settlements Land-use characteristics Urban fringe Chongqing Liangjiang New Area

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Porphyry mineralization in the Tethyan orogen

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Science China Earth Sciences 2020年第12期63卷 2042-2067页

作者： Rui wang Dicheng Zhu qing wang Zengqian Hou Zhiming Yang Zhidan zhao Xuanxue Mo State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing100083China Institute of Geology Chinese Academy of Geological Sciences(CAGS)Beijing100037China

The Tethyan metallogenic domain(TMD),as one of the three major domains in the world,extends over 10000 km from east to west,and has developed several world-class metallogenic belts,such as the Gangdese porphyry Cu belt,the Sanjiang metallogenic belt,the Iran porphyry Cu belt,the Pakistan porphyry Cu belt,the southeastern European epithermal gold deposit belt,and the Southeast Asian Sn *** formation and evolution of the TMD is mainly controlled by the multi-stage subduction of Tethys oceanic slabs,the opening and closing of several small ocean basins,and continent-continent *** Tethys oceans include the Proto-Tethys(Cambrian-Silurian),Paleo-Tethys(Carbonaceous-Triassic)and Neo-Tethys(Jurassic to Cretaceous),which in turn are formed by rifting from the Gondwana land at different times in different *** a series of geological processes such as oceanic opening and closing,continental collision and post-collisional reworking with intraplate deformation,various types of ore deposits are developed in the TMD,including porphyry deposits,epithermal deposits,VMS deposits,chromite deposits,Sn deposits and orogenic gold *** metallogenic processes of the TMD can be categorized into three stages.(1)Oceanic subduction:With the subduction of the oceanic slab and dehydration of basalt and sediments,the asthenospheric mantle was metasomatized with preliminary enrichment in metals under oxidized condition.(2)Continental subduction:Continental collision induced partial melting of the mantle wedge enriched the metals and water in mafic melts,which ascended from subarc depths to the lower crust,locally to the shallow crust for hydrothermal mineralization.(3)Post-collisional reworking:Partial melting of the mafic intrusives in the lower crust produced felsic melts under oxidized and water-rich conditions,which underwent crystal fractionation and transferred water and metals into hydrothermal fluids for *** large-scale porphyry minera

关键词： Tethyan ocean Magmatism Subduction mineralization Post-collisional mineralization.Porphyry deposit

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Ammonia pollution characteristics of centralized drinking water sources in China

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Journal of Environmental Sciences 2012年第10期24卷 1739-1743页

作者： qing Fu Binghui Zheng Xingru zhao Lijing wang Changming Liu College of Water Sciences Beijing Normal UniversityBeijing 100875China State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Source Water ProtectionChinese Research Academy of Environmental SciencesBeijing 100012China

The characteristics of ammonia in drinking water sources in China were evaluated during 2005-2009. The spatial distribution and seasonal changes of ammonia in different types of drinking water sources of 22 provinces, 5 autonomous regions and 4 municipalities were investigated. The levels of ammonia in drinking water sources follow the order of fiver 〉 lake/reservoir 〉 groundwater. The levels of ammonia concentration in river sources gradually decreased from 2005 to 2008, while no obvious change was observed in the lakes/reservoirs and groundwater drinking water sources. The proportion of the type of drinking water sources is different in different regions. In river drinking water sources, the ammonia level was varied in different regions and changed seasonally. The highest value and wide range of annual ammonia was found in South East region, while the lowest value was found in Southwest region. In lake/reservoir drinking water sources, the ammonia levels were not varied obviously in different regions. In underground drinking water sources, the ammonia levels were varied obviously in different regions due to the geological permeability and the natural features of regions. In the drinking water sources with higher ammonia levels, there are enterprises and wastewater drainages in the protected areas of the drinking water sources.

关键词： ammonia centralized drinking water sources distribution China

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Insights on pretreatment of Indian hematite fines in grate-kiln pelletizing process： the choice of grinding processes

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Journal of Iron and Steel Research International 2018年第5期25卷 506-514页

作者： De-qing Zhu Zheng-qi Guo Jian Pan zhao-yuan wang School of Minerals Processing and Bioengineering CentralSouth University Changsha 410083 Hunan China Engineering Design and Research Institute Northern HeavyIndustries Group Shenyang 110141 Liaoning China

Indian hematite fines are normally characterized by high iron grade and minor impurities, which are usually used for sinter fines. With macroscale operations technology of blast furnace in Indian, pellets, as a kind of high-quality materials, attract more and more attention. However, the hematite fines possess the coarse size. Hence, they inevitably need to be further finely ground for pelletizing before balling. The grinding behavior of Indian hematite fines was revealed by conducting the ball milling tests and determining the Bond ball mill work index （Wi）. The results show that Indian hematite fines have an excellent grindability with Wi of only 7.40-7.73 kWh/t, indicating that ball milling is an economically viable way to pretreat Indian hematite fines. Nonetheless, due to poor sedimentation and filtering properties of wet ground products, the dry ball milling is more appropriate to process Indian hematite fines. In addition, the superior quality green balls can be manufactured with dry ground products under the conditions of 0.5% bentonite dosage, 7.5% moisture and balling for 12 min, which further confirmed that the recommended pellet feed preparation technique is reasonable.

关键词： Indian hematite fine · Dry ball milling · Wet ball milling · Bond work index · Sedimentation characteristic ·Filtration characteristic

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Removal and transformation of organic matter during soil-aquifer treatment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 712-718页

作者： zhao qing-liang XUE Shuang YOU Shi-jie wang Li-na School of Municipal ＆ Environmental Engineering Harbin Institute of Technology Harbin 150090 China

This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC), nonbiodegradable dissolved organic carbon (NBDOC) and absorbance of ul-traviolet light at 254 nm (UV-254) averaged 71.46%, 68.05%, 99.31%, 33.27% and 38.96% across the soil columns, respectively. DOC/TOC ratios increased slightly with depth while BDOC/DOC ratios showed a converse trend. DOC exiting the soil-column system contained only a very small biodegradable fraction. SAT decreased the concentration of DOC present in feed water but increased its aromaticity, as indicated by specific ultraviolet light absorbance (SUVA), which increased by 50%～115% across the soil columns, indicating preferential removal of non-aromatic DOC during SAT. Overall, laboratory-scale SAT reduced triha-lomethane formation potential (THMFP), although specific THMFP increased. THMFP reduction was dominated by removal in chloroform. All samples exhibited a common general relationship with respect to weight: chloroform>dichlorobromomethane >dibromochloromethane>bromoform.

关键词： Soil-aquifer treatment (SAT) Organic matter Dissolved organic matter Trihalomethane formation potential Bio-degradable dissolved organic carbon (BDOC) Specific trihalomethane formation potential

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Crystal Structure and Luminescence of a Cd(Ⅱ) Compound Based on the 3,3’,5,5’-Tetrafluorobiphenyl-4,4’-dicarboxylate and Adenine Ligands

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Chinese Journal of Structural Chemistry 2020年第11期39卷 2041-2045页

作者： LIN zhao-Ting wang Yu-Ling LIU qing-Yan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

A one-dimensional(1 D) coordination polymer, [Cd2(TFBPDC)2(ad)2(CH3 OH)2]n(1), based on the 3,3’,5,5’-tetrafluorobiphenyl-4,4’-dicarboxylate(TFBPDC2-) and adenine(ad) ligands, was synthesized. Compound 1 crystallizes in the triclinic system, space group P1 with a = 9.7067(3), b = 9.9501(3), c = 11.6903(4) ?, α = 93.036(3), β = 107.793(3), γ = 107.107(3)°, V = 1014.77(6) ?3, Z = 2, C40H26F8N10O10Cd2, Mr = 1183.51, Dc = 1.937 g/cm3, μ = 1.160 mm-1, F(000) = 584, the final R = 0.0284 and wR = 0.0635 for 3791 observed reflections with Ⅰ> 2s(I). In 1, a pair of adenine(ad) ligands bridge two octahedrally coordinated Cd(Ⅱ) atoms to form a dinuclear [Cd2(ad)2] unit, which is linked by TFBPDC2- to generate a 1 D double chain. The neighboring chains are connected by N-H×××O hydrogen bonds to give a two-dimensional(2 D) layer, which is further linked by the O-H×××N hydrogen bonds to give a three-dimensional(3 D) supramolecular framework. IR spectrum, thermogravimetric analysis, and powder X-ray diffraction of 1 were provided. Compound 1 shows luminescent emission.

关键词： cadmium coordination polymer 3 3’ 5 5’-tetrafluorobiphenyl-4 4’-dicarboxylate adenine luminescence crystal structure

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Strain glass in defect-containing ferroelastic Ti_(44)Ni_(51)Nb_5 alloy

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Rare Metals 2015年第12期34卷 829-832页

作者： Guang-Yue Liao Bin Chen qing-Kun Meng Min-Juan wang Xin-qing zhao School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

An abnormal phenomenon was investigated in Ti44Ni51Nb5 alloy which exhibits an absence of martensite transformation and a negative temperature dependence of electrical resistivity with the temperature decreasing. X-ray diffraction (XRD) analysis shows the matrix phase keeps a B2 structure during cooling without a martensite transformation, and dynamic mechanical analysis displays a frequency-dependent AC modulus/loss anomaly at T g according to Vogel-Fulcher relation. Simultaneously, transmission electronic microscope (TEM) analysis manifests the superlattice spots at near 1/3 commensurate position, implying an existence of strain nanodomains with an R-like structure. And above experiment results provide evidence for the “strain glass” transition in defect-containing ferroelastic Ti44Ni51Nb5 alloy.

关键词： Strain glass transition Defect-containing TiNiNb Shape memory alloy

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A Novel 3D Extended Network Cobalt Paradodecatungstate:Synthesis,Characterization and Crystal Structure of [Co(H_2O)_5]_2[Co(H_2O)_4]_3[H_2W_(12)O_(42)]·11H_2O

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1167-1174页

作者： wang Jing-Ping REN qing zhao Jun-Wei NIU Jing-Yang Institute of Molecular and Crystal Engineering College of Chemistry and Chemical Engineering Henan University Kaifeng Henan 475001 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhcu Fujian 350002 China

A cobalt paradodecatungstate [Co（H2O）5]2[Co（H2O）4]3[H2W12O42]·11H2O has been successfully synthesized and structurally characterized by X-ray crystallography. Structure analysis indicates that the title compound is of monoclinic, space group P21/n, with a = 13.449（3）, b = 19.585（4）, c = 13.990（3） °A, = 113.79（3）°, V = 3371.8（12） °A^3, Z = 2, R = 0.0519 and wR = 0.1242. The title compound exhibits a novel 3D extended network structure constructed by interconnecting the paradodecatungstate polyanion [H2W12O42]^10- clusters and cobalt^11 coordination ions.

关键词： paradodecatungstate polyoxometalate cobalt Keggin structure

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Numerical study of water age influenced by tide and runoff in Daliaohe Estuary in China

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Journal of Hydrodynamics 2013年第1期25卷 39-47页

作者： wang Peng-cheng ZHANG Xue-qing zhao Qian SHI Ming-zhu College of Environmental Science and Engineering Ocean University of China National Marine Environment Monitoring Center

Based on the concept of the age, the water transport characteristics as the response to the runoff and the tide in Daliaohe Estuary in China are studied under different hydrodynamic conditions using a three-dimensional convection-diffusion model. The results show that the relationship between the average age at a specific position and the runoff could be expressed by a power function approximately. In the river channel, the runoff controls the water transport： it might take about 52 d, 27 d and 15 d for the water parcel to be transported from Sanchahe to the mouth during the dry, normal and rainy seasons, respectively. Outside the mouth, the tide is dominant even though the difference between the spring tide and the neap tide is less than 5 d, and the water parcel transports mainly along the northwest direction through the West Waterway and the southeast direction through the East Waterway. A significant age stratification emerges in the vicinity of the mouth, in which there exists a strong interaction between the tide and the runoff, and the age differences between the surface and the bottom could reach 7 d.

关键词： Daliaohe Estuary water age passive tracer numerical simulation

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The mechanism and products for co-thermal extraction of biomass and low-rank coal with NMP

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1512-1522页

作者： Jun zhao Hai-bin Zuo Jing-song wang qing-guo Xue State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The high-value utilization of low-rank coal would allow for expanding energy sources,improving energy efficiencies,and alleviating environmental *** order to use low-rank coal effectively,the hypercoals(HPCs)were co-extracted from two types of low-rank coal and biomass via N-methyl-2-purrolidinone(NMP)under mild *** structures of the HPCs and residues were characterized by proximate and ultimate analysis,Raman spectra,and Fourier transform infrared(FT-IR)*** carbon structure changes within the raw coals and HPCs were *** individual thermal dissolution of Xibu(XB)coal,Guandi(GD)coal,and the biomass demonstrated that the biomass provided the lowest thermal dissolution yield Y1 and the highest thermal soluble yield Y2 at 280℃,and the ash content of three HPCs decreased as the extraction temperature ***-thermal extractions in NMP at various coal/biomass mass ratios were performed,demonstrating a positive synergic effect for Y2 in the whole coal/biomass mass *** maximum value of Y2 was 52.25wt% for XB coal obtained with a XB coal/biomass of 50wt% *** maximum value of Y2 was 50.77wt% for GD coal obtained with a GD coal/biomass of 1:*** difference for the optimal coal/biomass mass ratios between XB and GD coals could be attributed to the different co-extraction mechanisms for this two type coals.

关键词： low-rank coal biomass co-thermal extraction NMP hypercoal

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