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1.
A model-based approach is here developed and applied to predict the long-term trends of indirect photochemical processes in the surface layer (5 m water depth) of Lake Maggiore, NW Italy. For this lake, time series of the main parameters of photochemical importance that cover almost two decades are available. As a way to assess the relevant photochemical reactions, the modelled steady-state concentrations of important photogenerated transients (OH, 3CDOM* and CO3-•) were taken into account. A multivariate analysis approach was adopted to have an overview of the system, to emphasise relationships among chemical, photochemical and seasonal variables, and to highlight annual and long-term trends. Over the considered time period, because of the decrease of the dissolved organic carbon (DOC) content of water and of the increase of alkalinity, a significant increase is predicted for the steady-state concentrations of the radicals OH and CO3−•. Therefore, the photochemical degradation processes that involve the two radical species would be enhanced. Another issue of potential photochemical importance is related to the winter maxima of nitrate (a photochemical OH source) and the summer maxima of DOC (OH sink and 3CDOM* source) in the lake water under consideration. From the combination of sunlight irradiance and chemical composition data, one predicts that the processes involving OH and CO3−• would be most important in spring, while the reactions involving 3CDOM* would be most important in summer.  相似文献   

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This study uses a building energy performance simulation to investigate the impact of predicted climate warming and the additional issue of building ageing on the energy performance for a library in Turin,Italy.The climate and ageing factors were modelled individually and then integrated together for several decades.Results from the climate-only simulation showed a decrease in thebuilding heating energy usage which outweighed the increase in the on-site cooling energy demand occurring in a warming scenario.The study revealed a high sensitivity of energy performance to building ageing,in particular due to HVAC(Heating,Ventilation and Air Conditioning) equipment efficiency degradation.Building ageing was seen to negatively affect the energy performance as it induced a further increase of the cooling energy usage in a warming climate,while it also counteracted the reduction of the heating energy usage resulting from warming.Simulations on the combination of mitigation techniques showed a number of potentially retrofit measures that would be beneficial for buildings to avoid an increase in the cooling energy usage due to climate warming.The combination of these retrofit techniques showed a potential decrease of 87.3% in the final cooling energy usage for the considered building.  相似文献   

4.
Over the past 15 years, housing supply for university students has increased significantly given the considerable attention provided by national institutions on the issue of student housing. In Italy, however, only approximately 4% of students live in university residences. Since 2001, interventions on existing buildings have accounted for approximately 60% of the overall measures proposed for new university residences; these interventions comprise most of the available public economic resources. The possibility of recovering and reusing existing buildings for university residences is remarkable for the city of Catania because most of the students are enrolled in university courses located within the historic city center. Moreover, abandoned buildings are currently a significant part of the city's architectural heritage. This research aims to develop an articulated and integrated set of frameworks to support the various phases of the design process for recovering and then reusing existing buildings as university residences. The proposed approach applies existing dimensional standards and environmental sustainability principles to a constructed building using traditional techniques.  相似文献   

5.

Landslides are among the most important and frequent natural calamities that cause severe socio-economic and human losses. After earthquakes, landslides are responsible for the greatest number of casualties and the largest amount of damage to man-made structures. On average, southern Italy is affected by a high spatial density of landslides due to its complex geological setting, which often predisposes it to slope instability phenomena under both natural and anthropogenic influences. Structurally complex formations are widespread in the southern Apennines and are characterized by high heterogeneity and very poor mechanical properties. Thus, these formations represent one of the main factors contributing to the predisposition of slopes to landsliding. In this paper, landslide-induced damage was investigated and analyzed in an area within the municipality of Agnone (Molise region), which is affected by a complex landslide that involves a structurally complex formation. The approaches used were based on six different methods that have previously been described in the literature, and a comparison of the results was made. Data regarding the damage, which consists largely of cracks observed in buildings and at the ground, were compiled through field surveys. The results were critically analyzed to note the advantages and constraints of each classification scheme. The aim of the work was to apply and compare different approaches in order to test the best and most accurate procedures for assessing damage due to landslides at the scale of individual buildings as well as to provide an objective assessment of the degree of landslide damage to structures and facilities.

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6.
One of the most challenging issues presently facing policymakers and public administrators in Italy concerns what to do with waste materials from building dismantling activities and to understand whether, and to what extent, the ever-increasing quantity of demolition waste can replace virgin materials. The paper presents the results from a research programme that was focused on the life cycle assessment (LCA) of a residential building, located in Turin, which was demolished in 2004 by controlled blasting. A detailed LCA model was set-up, based on field measured data from an urban area under demolition and re-design, paying attention to the end-of-life phase and supplying actual data on demolition and rubble recycling. The results have demonstrated that, while building waste recycling is economically feasible and profitable, it is also sustainable from the energetic and environmental point of view. Compared to the environmental burdens associated with the materials embodied in the building shell, the recycling potential is 29% and 18% in terms of life cycle energy and greenhouse emissions, respectively. The recycling potential of the main building materials was made available in order to address future demolition projects and supply basic knowledge in the design for dismantling field.  相似文献   

7.
Phoslock® is a lanthanum (La) modified bentonite clay that is being increasingly used as a geo-engineering tool for the control of legacy phosphorus (P) release from lake bed sediments to overlying waters. This study investigates the potential for negative ecological impacts from elevated La concentrations associated with the use of Phoslock® across 16 case study lakes. Impact-recovery trajectories associated with total lanthanum (TLa) and filterable La (FLa) concentrations in surface and bottom waters were quantified over a period of up to 60 months following Phoslock® application. Both surface and bottom water TLa and FLa concentrations were <0.001 mg L−1 in all lakes prior to the application of Phoslock®. The effects of Phoslock® application were evident in the post-application maximum TLa and FLa concentrations reported for surface waters between 0.026 mg L−1–2.30 mg L−1 and 0.002 mg L−1 to 0.14 mg L−1, respectively. Results of generalised additive modelling indicated that recovery trajectories for TLa and FLa in surface and bottom waters in lakes were represented by 2nd order decay relationships, with time, and that recovery reached an end-point between 3 and 12 months post-application. Recovery in bottom water was slower (11–12 months) than surface waters (3–8 months), most probably as a result of variation in physicochemical conditions of the receiving waters and associated effects on product settling rates and processes relating to the disturbance of bed sediments. CHEAQS PRO modelling was also undertaken on 11 of the treated lakes in order to predict concentrations of La3+ ions and the potential for negative ecological impacts. This modelling indicated that the concentrations of La3+ ions will be very low (<0.0004 mg L−1) in lakes of moderately low to high alkalinity (>0.8 mEq L−1), but higher (up to 0.12 mg L−1) in lakes characterised by very low alkalinity. The effects of elevated La3+ concentrations following Phoslock® applications in lakes of very low alkalinity requires further evaluation. The implications for the use of Phoslock® in eutrophication management are discussed.  相似文献   

8.
Methods of protecting an urban setting during underground construction and underworking of lands are analyzed in an example of the development of domestic regulatory-recommendatory documents. Attention is focused on methods used to protect underground utilities. The urgency of accumulated experience is assessed for modern conditions of underground construction. The paper is based on results of analysis of the problem’s status, which was conducted for the development of Standard [1]. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 18–22, May–June, 2008.  相似文献   

9.
The outrigger and belt truss system is commonly used as one of the structural systems to effectively control the excessive drift due to lateral load and minimize the risk of structural and non-structural damage. However, this prominent structural system has a demerit of excessive stressing to structural and nonstructural members during construction due to differential column shortening. In this paper, several potential construction methods managing the outrigger to perimeter column joints experiencing differential column shortening are discussed. These methods include fixed joint without any adjustment, delayed joint, delayed joint with shim plate adjustment, and outrigger damper (or lock-up-device) installed joint. Based on our research through computer analysis, large scale laboratory test, shake table test and real installation of the apparatus to a high-rise project, the building with outrigger damper or lock-up-device system has many advantages in terms of building performance, construction convenience, quality control and cost reduction.  相似文献   

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Mass movements are among the most dangerous natural hazards in mountainous regions. The present study employs machine learning (ML) models for mass movement susceptibility mapping (MMSM) in Iran based on a comprehensive dataset of 864 mass movements which include debris flow, landslide, and rockfall during the last 42 years (1977–2019) as well as 12 conditional factors. The results of validation stage show that RF (random forest) is the most viable model for mass movement susceptibility maps. In addition, MARS (multivariate adaptive regression splines), MDA (mixture discriminant additive), and BRT (boosted regression trees) models also provide relatively accurate results. Results of the AUC for validation of produced maps were 0.968, 0.845, 0.828, and 0.765 for RF, MARS, MDA, and BRT, respectively. Based on MMSM generated by RF model, 32% of study area is identified to be under high and very high susceptibility classes. Most of the endangered areas for mass movement are in the west and central parts of the Chaharmahal and Bakhtiari Province. In addition, our findings indicate that elevation, slope angle, distance from roads, and distance from faults are critical factors for mass movement. Our results provide a perspective view for decision makers to mitigate natural hazards.

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12.
Landslide susceptibility studies focus on producing susceptibility maps starting from landslide inventories and considering the main conditioning factors. The validity of susceptibility maps must be verified in terms of model accuracy and prediction skills. This paper deals with a GIS-based landslide susceptibility analysis and relative validation in a hilly-coastal test-area in Adriatic Central Italy. The susceptibility analysis was performed via bivariate statistics using the Landslide-Index method and a detailed (field-based) landslide inventory. Selection and mapping of conditioning factors and landslide inventories was derived from detail geomorphological analyses of the study area. The susceptibility map was validated using recent (shallow) landslides in terms of both model accuracy and prediction skills, via Success rate and Prediction rate curves, respectively. In addition, a pre-existing official landslide inventory was applied to the model to test whether it can be used when a detailed (field-based) inventory is not available, thereby extending its usability in similar physiographic regions. The outcome of this study reveals that slope and lithology are the main conditioning factor of landslides, but also highlights the key role of surficial deposits in susceptibility assessment, for both their type and thickness. The validation results show the effectiveness of the susceptibility model in both model accuracy and prediction skills given the good percentage of correctly classified landslides. Moreover, comparison of the susceptibility map with the official Regional landslides inventory proves the possibility of using the developed susceptibility model also in the absence of detailed landslide mapping, by considering inventories that are already available.  相似文献   

13.
中色地科矿产勘查股份有限公司投资加拿大上市公司——加纳克资源公司,获得丰厚投资回报.2010年中色地科控股子公司——中色金地资源科技有限公司将其在埃塞俄比亚瑞丰公司70%的权益转让给加纳克公司,获取400万加元现金补偿和350万股上市公司股票.之后,加纳克公司将注入的瑞丰矿权资产分拆上市,实现了资产价值的最大化,得到了市场的广泛认可.成功地探索了一条境外风险勘查投资退出和矿权资产证券化的新路子.  相似文献   

14.
文章以IKONOS影像为数据源,使用常用的4种融合方法:IHS、主成分变换、Brovey和Pansharp,对影像的全色及多光谱波段进行融合,并对各方法的融合影像进行了目视对比、统计分析和光谱分析,发现与原始影像相比,融合影像的纹理信息、光谱信息在Pansharp融合影像中保持得最好。选用相同的训练样本,对原始影像和融合影像应用支持矢量机的方法(SVM),分为裸地、煤堆、河流、矿山建筑物、道路等5类地物,并对分类结果进行了精度评价。在4种融合影像中,Pansharp融合影像的分类精度最高,总体分类精度达到82.89%。综合分析得出,Pansharp方法是一种较好的融合方法。  相似文献   

15.
基于传统PC砖制备工艺,总结了其优点及不足,提出了一种改进的可再生PC环保砖,对可再生PC环保砖的原料选择及制备方法进行了分析,提升了PC砖的各项指标,解决了传统PC砖的耐磨性差、易破损等问题,并对可再生PC环保砖进行了市场应用分析,研究结果表明:该PC砖制作工艺流程简单,性能优良,市场应用前景好。  相似文献   

16.
The primary goal of this research was to explore the potential of farmer's knowledge as a source of information on the past and present cultural landscapes, focusing on the land-use system, the cultural heritage, and the farmer's perception of landscape changes, from the 1950s to the present day. For this purpose, 42 semi-structured interviews were conducted from a random sample of 10% of the villages in an area of the Northern Mountains of Galicia (NW Spain). As shown in farmers’ reports, the main crops in the 1950s were wheat or rye, potatoes or maize (only near the coast) and turnips. Scrubland areas were an essential resource for pasture, litter, temporary crops and charcoal, whereas deciduous forest was mainly used as a source of wood for carpentry, firewood and litter. Agriculture was the main economic activity, whereas crafts and other activities in the fisheries or forestry industry were secondary. Granaries, watermills and stone laundry basins were the most frequent elements of built heritage that was mentioned in the interviews. Farmers were also comprehensively aware of the broad changes that occurred in the landscape. The results indicate that farmer's knowledge is a valuable source of information for documenting past and present land-use practices, local cultural heritage and changes in the landscape, all of which are helpful for the design of landscape-orientated policies. Moreover, observed ancestral cultural practices, such as extensive grazing in scrubland areas, may be promoted as strategies for helping the sustainability of cultural landscapes in the study area and in other areas with similar characteristics.  相似文献   

17.
Starting in July 2000, treated wastewater of urban origin has been used for the "Serres de Pals" golf course irrigation (Girona, Spain). To evaluate if the soil and the aquifer underneath are affected by the utilization of this type of water, samples have been taken along a period of several months from the wastewater treatment plant, the stabilization lagoon, groundwater and soil profiles. Analyses have been performed for total coliforms and aerobic bacteria, soil water pressure and soil water content as well as chemical analyses of the irrigation water, aquifer and water of the vadose zone. Soil profiles taken at several times during the study indicate the absence of coliforms except for a short period during summer. In the vadose zone an increase of more than 1000 mg kg(-1) of NaO(2) in the top 60 cm of soil was observed while Cl(-) concentration in the aquifer reached up to 1200 mg l(-1) ten months after starting the irrigation.  相似文献   

18.
In the present study we investigated possible contamination by trace elements due to the oil slick caused by the shipwreck of the Prestige oil tanker, in two species of brown macroalgae (Fucus vesiculosus and Fucus ceranoides) collected from the coastal area most severely affected by the spill (Galicia, NW Spain). The oil slick apparently did not cause significant increases in the concentrations of the trace elements studied, except vanadium. It appears that the magnitude of terrestrial inputs to coastal waters is sufficiently high to mask the inputs of trace elements from the fuel. The observed exception of V suggests that bioaccumulation of this element by the two species of Fucus may be used to indicate exposure to petrochemical products similar to the Prestige fuel. The findings of the study are another example of the importance of the existence of Environmental Specimen Banks for studies of this type.  相似文献   

19.
In order to estimate atmospheric metal deposition in Southern Europe since the beginning of the Industrial Period (~ 1850 AD), concentration profiles of Pb, Zn and Cu were determined in four 210Pb-dated peat cores from ombrotrophic bogs in Serra do Xistral (Galicia, NW Iberian Peninsula). Maximum metal concentrations varied by a factor of 1.8 for Pb and Zn (70 to 128 μg g−1 and 128 to 231 μg g−1, respectively) and 3.5 for Cu (11 to 37 μg g−1). The cumulative metal inventories of each core varied by a factor of 3 for all analysed metals (132 to 329 μg cm−2 for Pb, 198 to 625 μg cm−2 for Zn and 22 to 69 μg cm−2 for Cu), suggesting differences in net accumulation rates among peatlands. Although results suggest that mean deposition rates vary within the studied area, the enhanced 210Pb accumulation and the interpretation of the inventory ratios (210Pb/Pb, Zn/Pb and Cu/Pb) in two bogs indicated that either a record perturbation or post-depositional redistribution effects must be considered. After correction, Pb, Zn and Cu profiles showed increasing concentrations and atmospheric fluxes since the mid-XXth century to maximum values in the second half of the XXth century. For Pb, maximum fluxes were observed in 1955-1962 and ranged from 16 to 22 mg m−2 yr−1 (mean of 18 ± 1 mg m−2 yr−1), two orders of magnitude higher than in the pre-industrial period. Peaks in Pb fluxes in Serra do Xistral before the period of maximum consumption of leaded petrol in Europe (1970s-1980s) suggest the dominance of local pollutant sources in the area (i.e. coal mining and burning). More recent peaks were observed for Zn and Cu, with fluxes ranging from 32 to 52 mg m−2 yr−1 in 1989-1996, and from 4 to 9 mg m−2 yr−1 in 1994-2001, respectively. Our results underline the importance of multi-core studies to assess both the integrity and reliability of peat records, and the degree of homogeneity in bog accumulation. We show the usefulness of using the excess 210Pb inventory to distinguish between differential metal deposition, accumulation or anomalous peat records.  相似文献   

20.
古建筑群消防规划特殊性研究   总被引:3,自引:0,他引:3  
针对古建筑群特有的消防安全现状 ,对其消防规划的特殊性进行了分析 ,提出了几点对策。  相似文献   

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