基于GIS的城市绿地空属一体化信息库构建及维护的实用方法研究

准确实时的城市绿地资源信息数据库是绿地信息化和精细化管理的前提,但实际却面临空间信息延误、绿地属性信息缺失的难题,严重制约了绿地信息化管理的时效性和准确性。本文在分析城市绿地空间和结构的特点之上,基于GIS提出了一套城市绿地资源空属一体化信息库构建和维护的实用方法。研究基于GIS建立了一套空间信息获取和校核的方法流程,包括基于遥感的绿色信息提取方法、空间信息核准的校核单元、核准内容、核准方法等;提出了基于绿地分类的属性数据库构建的方法流程,包括数据库字段设计和调查方法等。该空属一体化的建库和维护方法能够为各地园林绿化的信息化管理提供实用的方法支撑,可以有效解决由于信息更新滞后带来的信息管理系统使用"夭折"问题。

Boosting CO_(2) photoreduction by synergistic optimization of multiple processes through metal vacancy engineering

The photoreduction of greenhouse gas CO_(2) using photocatalytic technologies not only benefits en-vironmental remediation but also facilitates the production of raw materials for chemicals.Howev-er,the efficiency of CO_(2) photoreduction remains generally low due to the challenging activation of CO_(2) and the limited light absorption and separation of charge.Defect engineering of catalysts rep-resents a pivotal strategy to enhance the photocatalytic activity for CO_(2),with most research on met-al oxide catalysts focusing on the creation of anionic vacancies.The exploration of metal vacancies and their effects,however,is still underexplored.In this study,we prepared an In2O3 catalyst with indium vacancies(VIn)through defect engineering for CO_(2) photoreduction.Experimental and theo-retical calculations results demonstrate that VIn not only facilitate light absorption and charge sepa-ration in the catalyst but also enhance CO_(2) adsorption and reduce the energy barrier for the for-mation of the key intermediate*COOH during CO_(2) reduction.Through metal vacancy engineering,the activity of the catalyst was 7.4 times,reaching an outstanding rate of 841.32μmol g(-1)h^(-1).This work unveils the mechanism of metal vacancies in CO_(2) photoreduction and provides theoretical guidance for the development of novel CO_(2) photoreduction catalysts.

INVESTIGATION OF FOAM-METAL INTERFACE BEHAVIORS DURING MOLD FILLING OF MAGNESIUM ALLOY LFC PROCESS

The visual observation of the mold filling and the standard analysis-of-variance （ANOVA） for the velocity of the filling metal are conducted to study foam-metal interface behaviors during the mold filling of the lost foam casting （LFC） process of the magnesium alloy. Results show that the foam primarily melts into liquid products instead of gasifying at the pouring temperature of the magnesium alloy. Without the vacuum, the metal fills smoothly with a slightly convex metal front, and the velocity of the filling metal is low and continually decreases as the foam is displaced. The mold filling is governed by the removal of foam decomposition products at the foam-metal interface. However, when the vacuum is applied, the mold filling is controlled by the foam decomposition rate at the foam-metal interface. A pronounced irregular and concave metal front is formed. The velocity of the metal front varies tremendously during the mold filling process and is ruleless. The metal velocity increases rapidly, and the vacuum shows a strong interaction effect with the pouring temperature on the metal velocity. As the vacuum continues to increase, the pouring temperature becomes the most significant factor for the mold filling, while both the vacuum effect and the interaction effect between the vacuum and the pouring temperature on the metal velocity are substantially reduced. Based on experimental results, a model for the foam thermal degradation and the removal of decomposition products occurred at the foam-metal interface is presented during the mold filling of the magnesium alloy LFC process under the vacuum.

Preparation of metal zinc from hemimorphite by vacuum carbothermic reduction with CaF_2 as catalyst

Zn reduction was investigated by the vacuum carbothermic reduction of hemimorphite with or without CaF2 as catalyst.Results indicate that CaF2 can catalyze the carbothermic reduction of zinc silicate,decrease the reaction temperature and time.The lower the reaction temperature and the more the amount of CaF2,the better the catalytic effect.The optimal process condition is obtained as follows：the addition of about 10% CaF2,the reaction temperature of 1373 K,the molar ratio of C to ZnTotal of 2.5,the pressure of system lower than 20 kPa,the reaction time of about 40 min.Under the optimal process condition,the zinc reduction rate is about 93% from hemimorphite.

Spatial interpolation method based on integrated RBF neural networks for estimating heavy metals in soil of a mountain region

A novel spatial interpolation method based on integrated radial basis function artificial neural networks （IRBFANNs） is proposed to provide accurate and stable predictions of heavy metals concentrations in soil at un- sampled sites in a mountain region. The IRBFANNs hybridize the advantages of the artificial neural networks and the neural networks integration approach. Three experimental projects under different sampling densities are carried out to study the performance of the proposed IRBFANNs-based interpolation method. This novel method is compared with six peer spatial interpolation methods based on the root mean square error and visual evaluation of the distribution maps of Mn elements. The experimental results show that the proposed method performs better in accuracy and stability. Moreover, the proposed method can provide more details in the spatial distribution maps than the compared interpolation methods in the cases of sparse sampling density.

长期均线预示大市走势

中国股市出现短期上升走势,所谓一根大阳线,千军万马来相见。对大市走势看多看空属见仁见智的事,但看好走势则不能胡乱地鼓吹,看空亦不能死命喊跌,比如有些人喊“逢九必升”就显得不够理智。中国股市的上证指数1990年诞生,只有1999年及2009年可做参考,如何能“逢九必升”?看看美国股市,1929年跌到扑街,1969年亦是跌的,1909、1939年基本持平。

Spatial Prediction of Heavy Metal Pollution for Soils in Peri-Urban Beijing, China Based on Fuzzy Set Theory

Fuzzy classification combined with spatial prediction was used to assess the state of soil pollution in the peri-urban Beijing area. Total concentrations of As, Cr, Cd, Hg, and Pb were determined in 220 topsoil samples （0-20 cm） collected using a grid design in a study area of 2 600 kin2. Heavy metal concentrations were grouped into three classes according to the optimum number of classes and fuzziness exponent using the fuzzy comean （FCM） algorithm. Membership values were interpolated using ordinary kriging. The polluted soils of the study area induced by the measured heavy metals were concentrated in the northwest corner and eastern part, especially the southeastern part close to the urban zone, whereas the soils free of pollution were mainly distributed in the southwestern part. The soils with potential risk of heavy metal pollution were located in isolated spots mainly in the northern part and southeastern corner of the study region. The FCM algorithm combined with geostatistical techniques, as compared to conventional single geostatistical kriging methods, could produce a prediction with a quantitative uncertainty evaluation and higher reliability. Successful prediction of soil pollution achieved with FCM algorithm in this study indicated that fuzzy set theory had great potential for use in other areas of soil science.

Spatial Patterns of Soil Heavy Metals in Urban-Rural Transition Zone of Beijing

To identify the main sources responsible for soil heavy metal contamination, 70 topsoils were sampled from the Daxing County in the urban-rural transition zone of Beijing. The concentrations of heavy metals Cu, Zn, Pb, Cr, Cd, Ni, As, Se, Hg, and Co; the soil texture; and the organic matter content were determined for each soil sample. Descriptive statistics and geostatistics were used to analyze the data, and Kriging analysis was used to estimate the unobserved points and to map the spatial patterns of soil heavy metals. The results showed that the concentrations of all the soil heavy metals exceeded their background levels with the exception of As and Se. However, only the Cd concentration in some areas exceeded the critical value of the national soil quality standard. The semivariance analysis showed that the spatial correlation distances for soil Cu, Zn, Cr, Cd, As, Ni, and Co ranged from 4.0 to 7.0 km, but soil Se, Pb, and Hg had a larger correlation distance. Soil Co, Se, Cd, Cu and Zn showed a strong spatial correlation, whereas the other soil heavy metals showed medium spatial correlation. Soil heavy metal concentrations were related to soil texture, organic matter content, and the accumulation of heavy metals in the soils, which was because of air deposition and use of water from the Liangshui, Xinfeng, and Fenghe rivers that are contaminated by wastewater and sewage for the purpose of irrigation of fields. Hence, a comprehensive treatment plan for these rivers should be formulated.

A new electromagnetic functional material composed of metallic hollow micro-spheres

This paper presents a new electromagnetic functional material developed byelectron-less nickel deposition technique, with a single hollow micro-sphere as the core templateand a thin nickel layer as the shell. The micrograph taken by a scanning electron microscope showsthe microstructures of the materials in detail. Scattering parameters of the waveguide sample holderfilled with the materials have been obtained over X band. The electromagnetic parameters computedfrom the measured S parameters show that the material with metallic hollow spheres has as highrelative permeability μ'_r as 19.0 with about 0.6 magnetic loss tangent over the whole bandwidth.Compared to the material with non-metallic spheres, the permeability μ'_r and the magnetic losstangent μ'_r increase greatly, while the permittivity remains lower than 1.8.

Concave Minimization for Sparse Solutions of Absolute Value Equations

Based on concave function, the problem of finding the sparse solution of absolute value equations is relaxed to a concave programming, and its corresponding algorithm is proposed, whose main part is solving a series of linear programming. It is proved that a sparse solution can be found under the assumption that the connected matrixes have range space property(RSP). Numerical experiments are also conducted to verify the efficiency of the proposed algorithm.

Spatial Distribution of Heavy Metals in Agricultural Soils of an Industry-Based Peri-Urban Area in Wuxi, China

In industry-oriented peri-urban areas, the heavy metal accumulation in soils caused by industrialization has become a potential threat. The top soil samples from 27 paddy fields and 75 vegetable fields were collected from a typical industry- based peri-urban area of about 8 km^2 in Wuxi, China, to study the accumulation and distribution of As, Hg, Cu, Zn, Pb, Cr, and Cd in comparison with heavy metal contents in soils near developed industrial sites （Guangzhou, China; Wallsend Burn of Tyneside, UK; and Osnabrück, Germany）. Kriging interpolation was used to determine the metals, spatial distribution. The results showed that most soils, compared to the background values, contained elevated contents of As, Hg, Cu, Zn, and Pb with some having elevated contents of Cd and Cr. Except for less than 10% of the soil samples of Cu, Zn and Cd contents, these heavy metal contents were lower than the soil threshold levels of the Grade Ⅱ criteria for the Chinese environmental quality standard. Probably, because of the scattered distribution and diversity of industries in the study area, spatial distributions of these heavy metals from Kriging interpolation indicated little similarity. Nevertheless, when compared with other areas in the Taihu Lake region, mean contents of Cu, Zn, Pb, and Cd were relatively high in the Wuxi peri-urban area. Additionally, compared to soils in agricultural areas around Guangzhou, Osnabrück, or Wallsend Burn, contents of most heavy metals in soils from this area were lower.

Mapping Detailed Soil Property Using Small Scale Soil Type Maps and Sparse Typical Samples

Soil type maps at the scale of I Z 1 000 000 are used extensively to provide soil spatial distribution information for soil erosion assessment and watershed management models in China. However, the soil property maps produced through conventional direct linking method usually suffer low accuracy as well as the lack of spatial details within a soil type polygon. This paper presents an effective method to produce detailed soil property map based on representative samples which were extracted from each polygon on the 1 ： 1 000 000 soil type map. The representative sample of each polygon is defined as the location that can represent the largest area within the polygon. The representativeness of a candidate sample is determined by calculating the soil-forming environment condition similarities between the sample and other locations. Once the representative sample of each polygon has been chosen, the property values of the existing typical samples are assigned to the corresponding representative samples with the same soil type. Finally, based on these representative samples, the detailed soil property map could be produced by using existing digital soil mapping methods. The case study in XuanCheng City, Anhui Province of China, demonstrated the proposed method could produce soil property map at a higher level of spatial details and accuracy： 1） The soil organic matter （SOM） map produced based on the representative samples can not only depict the detailed spatial distribution of SOM within a soil type polygon but also largely reduce the abrupt change of soil property at the boundaries of two adjacent polygons. 2） The Root Mean Squared Error （RMSE） of the SOM map based on the representative samples is 1.61, and it is 1.37 for the SOM map produced by using conventional direct linking method. Therefore, the proposed method is an effective approach to produce spatial detailed soil property map with higher accuracy for environment simulation models.

Daily Ambrosia Pollen Concentration in the Air of Ankara,Turkey (1990-1999)

The airborne ragweed pollen spectrum was investigated in the air of Ankara, Turkey for aperiod of ten years (1990-1999) using a Burkard seven-day volumetric recording trap. In our study period,long distance transported Ambrosia pollen has been registered. Daily pollen levels varied from low to highin Burge抯 system. In last three years, the pollen concentration of Ambrosia showed a clear increasingtendency. Our results prove that ragweed pollen may be an important threat for ragweed sensitive patientsin Ankara city in near future.

Micro-nanostructural designs of bifunctional electrocatalysts for metal-air batteries

Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)have limited the practical application of rechargeable metal-air batteries.Most of reviews were focused on single functional electrocatalysts while few on bifunctional electrocatalysts.It is indispensable but challenging to design a bifunctional electrocatalyst that is active and stable to the two reactions.Recently,attempts to develop high active bifunctional electrocatalysts for both ORR and OER increase rapidly.Much work is focused on the micro-nano design of advanced structures to improve the performance of bifunctional electrocatalyst.Transition-metal materials,carbon materials and composite materials,and the methods developed to prepare micro-nano structures,such as electrochemical methods,chemical vapor deposition,hydrothermal methods and template methods are reported in literatures.Additionally,many strategies,such as adjustments of electronic structures,oxygen defects,metal-oxygen bonds,interfacial strain,nano composites,heteroatom doping etc.,have been used extensively to design bifunctional electrocatalysts.To well understand the achievements in the recent literatures,this review focuses on the micro-nano structural design of materials,and the related methods and strategies are classed into two groups for the improvement of intrinsic and apparent activities.The fine adjustment of nano structures and an in-depth understanding of the reaction mechanism are also discussed briefly.

On Growth and Covering Theorem for Almost Spiallike Mapping of Type β with Order α

Let f（x） be an almost spirallike mapping of type β with order B on unit ball B of complex Banach space X. In this paper, we consider the growth and covering theorems for f（x）, we also prove that the estimation is precise when β=0 and still give growth upper bound and distortion upper bound for subordinate mapping. This result include some results known.

SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE

Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp les are taken at different locations,inclu ding three kinds of covering soil,th ree different depths of soil layers a nd four different covering ages of covering soil.The s patial-temporal variation of heavy metal element content in reclamatio n soil is stud-ied.The results indicate that the co ntent of heavy metal elements is decreasing year after year;the determin ant reason why the content of heavy metal elemen ts at 60cm depth layer is higher than t hat at 30cm depth layer and surface is fertiliz-er and manure application;the metal elements mainly come from external environment;there is no metal pollut ion coming from mother material(coal mining wastes)in plough layer of covering soil.

Prediction of Soil Depth from Digital Terrain Data by Integrating Statistical and Visual Approaches

Information about the spatial distribution of soil attributes is indispensable for many land resource management applications; however, the ability of soil maps to supply such information for modern modeling tools is questionable. The objectives of this study were to investigate the possibility of predicting soil depth using some terrain attributes derived from digital elevation models （DEMs） with geographic information systems （GIS） and to suggest an approach to predict other soil attributes. Soil depth was determined at 652 field observations over the A1-Muwaqqar Watershed （70 km2） in Jordan. Terrain attributes derived from 30-m resolution DEMs were utilized to predict soil depth. The results indicated that the use of multiple linear regression models within small watershed subdivisions enabled the prediction of soil depth with a difference of 50 cm for 77% of the field observations. The spatial distribution of the predicted soil depth was visually coincided and had good correlations with the spatial distribution of the classes amalgamating three terrain attributes, slope steepness, slope shape, and compound topographic index. These suggested that the modeling of soil-landscape relationships within small watershed subdivisions using the three terrain attributes was a promising approach to predict other soil attributes.

Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths （3700-4200 m） at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions （e.g., nutrient and thermal deficits, plant interactions） across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran＇s eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.

CO oxidation over Au/ZrLa-doped CeO_2 catalysts: Synergistic effect of zirconium and lanthanum

The physicochemical properties of nanosized Au catalysts supported on doped CeO2 and their cata‐lytic performance for the CO oxidation reaction were investigated. The Au/Zr‐doped CeO2 catalyst is much more active than undoped Au/CeO2, while Au/ZrLa‐doped CeO2 shows the highest activity. Characterization of the catalysts by X‐ray diffraction, transmission electron microscopy （TEM）, high‐resolution TEM, and the X‐ray absorption fine structure technique shows high homogeneity of the oxide supports and well‐dispersed nanosized Au nanoparticles. Raman spectroscopy, X‐ray photoelectron spectroscopy, and H2‐tempeature‐programmed reduction show that the surface oxygen species are the main factor for the catalytic activity in the CO oxidation reaction, while the supported Au species can improve the redox properties and create oxygen vacancy sites on the support. The oxidation state of Au is not the main factor governing the activity of Au/doped‐CeO2 catalysts. Additionally, the synergistic effect of Zr and La is discussed.

DEVELOPMENT OF A GIS DATA MODEL WITH SPATIAL,TEMPORAL AND ATTRIBUTE COMPONENTS BASED ON OBJECT-ORIENTED APPROACH

This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model includes two major parts: (a) modeling the signal objects by STA-object elements, and (b) modeling relationships between STA-objects. As an example, the STA-model is applied for modeling land cover change data with spatial, temporal and attribute components.