哈山地区白垩系沉积相研究

哈拉阿拉特山地区位于准噶尔盆地西北缘前陆褶皱冲断带上,油气资源丰富,但目前的研究中尚缺乏明确的沉积相划分。本文对白垩系底部开展沉积相研究,明确了哈山白垩系地层及砂体平面展布规律。对哈拉阿拉特山地区进一步的油气勘探活动具有一定的指导和借鉴意义。     

基于和谐与共生理念的城市建筑设计——苏州市公安应急指挥中心创作有感

以苏州市公安应急指挥中心方案为例,基于建筑设计与城市规划结合的设计理念,从建筑功能、空间形态、总体布局等多方面详细阐述如何打造一个既能满足复杂的功能需求,又能因地制宜、和谐融合,为城市整体环境添光增彩的综合性建筑体。     

Defining and characterizing urban boundaries: A fractal analysis of theoretical cities and Belgian cities

In this paper we extract the morphological boundaries of urban agglomerations and characterize boundary shapes using eight fractal and nonfractal spatial indexes. Analyses were first performed on six archetypal theoretical cities, and then on Belgium’s 18 largest towns. The results show that: (1) the relationship between the shape of the urban boundary (fractal dimension, dendricity, and compactness) and the built morphology within the urban agglomeration (fractal dimension, proportion of buildings close to the urban boundary) is not straightforward; (2) each city is a unique combination of the morphological characteristics considered here; (3) due to their different morphological characteristics, the planning potential of Flemish and Walloon cities seems to be very different.     

Wood characterization for energy application proceeding from pruning Morus alba L., Platanus hispanica Münchh. and Sophora japonica L. in urban areas

Pruning urban forests generates significant amounts of lignocellulosic biomass every year. The energy potential of this biomass is unclear. The aim of this research was direct analysis of the gross calorific value (GCV), elemental composition and moisture content of Morus alba L., Platanus hispanica Münchh. and Sophora japonica L. by means of laboratory equipment. This analysis allowed for further development of indirect GCV prediction models which are economically attractive and less time consuming to direct analysis. These models presented high coefficients of determination (R² 0.66–0.96). It has been determined that the species with highest mean GCV is S. japonica L. (19615.68 kJ/kg-dry sample) whereas the one with the lowest is the M. alba L. (18192.87 kJ/kg-dry sample). Elemental analysis showed highest carbon (48.22%), hydrogen (6.17%) and nitrogen (1.16%) content in S. japonica L. in dry samples. Sulfur was constant at the level 0.05% for all analyzed species. Also percentage of bark and wood density were determined. Mean percentage of bark was highest for P. hispanica Münchh. (13.05%) while wood density was highest for S. japonica L. (0.86 g cm⁻³). This way the research has proven that the biomass produced by pruning urban forests appears to be an interesting source of renewable energy.     

基于都市发展阶段论的城市居住隔离研究

本文归纳并总结我国居住隔离研究的现状,从研究成果及应用性、研究层面及针对性和规划对策三方面评述居住隔离研究存在的问题,在此基础上引入并剖析都市发展阶段论与居住隔离的内在关联,结合我国城市化特点构建基于都市发展阶段论的居住隔离研究框架,探讨我国居住隔离问题的应对策略,并着重论述框架中各类居住隔离问题的混居措施。     

Modelling and development of recycled water conditioning of copper-molybdenum ores processing

Current use of enrichment and processing technologies of ores requires the introduction of closed circuits of water treatment. A decrease in technological properties is caused by accumulations of ion-molecular components in the circulating water. The objective of the simulation is to determine the maximum allowable concentrations of ions and molecules as well as the choice of conditions for deposition or adsorption. First of all, our examinations decrease the concentration of copper ions and fatty acids in the circulating water. By pre-mixing water with the highest concentration of these ions, a reduction of copper ion and fatty acid concentrations in the recycled water occurs. The results do not only ensure the achievement of the maximum permitted concentration (MPC) of copper and iron, significantly reducing the amount of oxidized copper, they also make it possible to use the united sewage as current water for the flotation process. Mixing and adding filtrate of tailings, discharges of urban wastewater treatment and effluent of ash pit of thermal power stations (TPS) to recycled water causes an increase in the capacity of the enrichment plant by 15–17%.     

Understanding the impact of High Speed Railway on urban innovation performance from the perspective of agglomeration externalities and network externalities

Transportation infrastructure and innovation play an important role in promoting regional economic growth. However, previous studies have mainly focused on the economic agglomeration by increased accessibility, but ignored the important on inter-city economic linkages and the network externalities it generated. Based on the externality perspective, this paper uses the propensity score matching model (PSM-DID) and spatial econometric model to analyze the heterogeneous impact of HSR opening on urban innovation performance and compare the differential effects of agglomeration externalities and network externalities on knowledge spillovers. The empirical results suggest the following: (1) The opening of HSR significantly improves urban innovation performance, but there is significant spatial heterogeneity. (2) The opening of HSR not only promotes the agglomeration of production factors to cities, but also strengthens inter-city economic connections, thus improving urban innovation performance through agglomeration externalities and network externalities. However, compared to agglomeration externalities, network externalities have a superior strength of impact on urban innovation performance. (3) From the dynamic effect perspective, the opening of HSR has a hysteresis effect on urban innovation of 2–3 years, and differences exist between cities.     

Why underground space should be included in urban planning policy – And how this will enhance an urban underground future

Cities worldwide tend to overlook an invaluable asset that lies beneath their surfaces. Most cities and urban regions are unaware of the benefits underground space use has to offer, both for climate inflicted and spatial constraints: In many cities, infrastructure development is being outpaced by population growth. Climate change effects are requiring radical new approaches in terms of coping with for example excessive rainfall. The available space at the surface is rapidly being used up and the biggest danger is that built-up spaces are taking over the public green spaces of cities thereby threatening livability and quality of life. Urban underground space forms a societal asset, which is often unappreciated and underestimated in terms of the role it can play within dynamic city environments and associated challenges.This paper will explore the ways in which urban underground space can be optimally integrated into the dynamic urban context. It also explores the often contradictory functions that make underground space use complicated from a planner’s perspective. The first-come-first-served strategy of underground space use has left many cities wondering how they are going to cope with the self-inflicted “chaos” under the surface. The often mono-functional uses of the underground lead to sub-optimal space use. Most cities and urban regions are unaware of the benefits underground space use has to offer. In guiding the future use of urban underground space, a comprehensive policy framework guiding its development is lacking on which decisions can be based. This often leads to the non-sustainable use of this important asset. It will be argued that both vision and planning are needed to be able to make the best use of this underrated underground real estate.The authors will also debate that just understanding the potential of underground space is not enough. Realising its actual potential and facilitating its development will require a spatial dialogue between many stakeholders, including planners, engineers, developers and public decision makers.     

Habitat structure influences below ground biocontrol services: A comparison between urban gardens and vacant lots

Urban agriculture offers a framework for local self-reliance by provisioning food security, employment opportunities, and other community benefits. However, urban agriculture must rely on the supporting and regulating services of the soil food web. Hence, we quantified belowground biocontrol activity in urban gardens and vacant lots in two post-industrial cities using an in situ insect baiting technique. Due to the differences in habitat structure, we hypothesized that belowground biocontrol services will differ between gardens and vacant lots and the influence of habitat structure would differ with the type of biocontrol organism. Results revealed that biocontrol activity, as assessed by % mortality of baited insects, varied between 51% and 98% with higher activity often recorded in vacant lots than gardens. Major contributions to bait insect mortality were by ants, followed by microbial pathogens and entomopathogenic nematodes, respectively. Ants showed higher (p < 0.0001) % mortality in vacant lots (60% ± 33.4%) than in urban gardens (33.3% ± 22.2%) whereas microbial pathogens exhibited higher (p < 0.0001) mortality in gardens (27.8% ± 15%) than vacant lots (8.3% ± 16.7%). Ants caused higher (p < 0.0001) mortality when larger-mesh size cages were used compared with the smaller-mesh size cages, but mortality by microbial pathogens did not differ with cage type. The high biocontrol activity indicates the resilience of the soil food web in urban ecosystems and the differential effects of habitat structure on biocontrol activity can help guide landscape planning and vegetation management to enhance urban environments and boost local self-reliance.     

Shaking table tests on seismic measures of a model mountain tunnel

A series of three dimensional (3D) shaking table tests were carried out to investigate the mechanism and effect of seismic measures of mountain tunnel using a scaled model based on a real tunnel. Key technical details of the experiment, including similarity relations, seismic measures simulation, boundary conditions, sensor layout, modeling methods, and ground motion input were presented. Main seismic measures, including reinforcing surrounding rock with anchors, increasing lining flexibility with steel wire mesh, and installing seismic isolation layer between reinforced surrounding rock and tunnel lining, were investigated in this study. Experiment results show that: (1) adding a layer of steel wire mesh in the tunnel lining can improve the flexibility and seismic performance and also may effectively prevent radial cracks from crossing the lining; (2) installing a geofoam isolation layer between the reinforced surrounding rock and the tunnel lining reduces dynamic earth pressure by 70–90% for the lining without a seismic isolation layer; (3) the flexible joints can effectively avoid global failures of tunnel lining for they reduce dynamic strain and bending force in the tunnel lining and decrease the seismic energy transmission along the lining in axial direction; (4) reinforcing surrounding rock with anchors significantly reduces dynamic earth pressure and strain of the lining by about 50%. In addition, the length of seismic reinforcement for general mountain tunnel portal is recommended to be 50 m from the tunnel portal along the axial direction.