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1.
Bulletin of Engineering Geology and the Environment - A better understanding of the spatiotemporal evolution of landslides in urban zones is a key factor in assessing the risk of future slides...  相似文献   

2.
Bulletin of Engineering Geology and the Environment - In the Tebessa area, the nature of geological formations in the subsurface is influenced considerably the superstructures built on them by the...  相似文献   

3.
1试验目的(简介)新疆是我国西部地震多发地区,发震的震级大、频度高。新疆喀什地区近些年来多次发生6级以上地震,给人民的生命财产造成了重大损失。新疆喀什市老城区(如图1所示)是国家历史文化名城(图2、图3是有维吾尔族特色、以民居为主的生土建筑,一些具有文化保护价值的房屋已有百年以上的历史)。现场调查表明,这些生土房屋承重墙体的建筑材料强度低、结构整体性差,地处8度抗震设防区,缺乏必要的抗震措施,抗震能力存在不足,难以满足相应的抗震设防要求。  相似文献   

4.
This paper reports a study of pollution in the coastal waters of Jijel, Algeria, using algae Ulva lactuca and Corallina officinalis as bioindicators. Samples of seawater and algae were collected at four different stations from the coast of Jijel, during the period of April–June 2014. The heavy metal content (Pb and Zn) was determined in seawater and in the algae tissue by the technique of atomic absorption spectrophotometry. In seawater, the contents of heavy metals vary from 0.017 to 0.03 mg/l (Pb) and 0.235 to 0.873 mg/l. In the algae tissues, metals concentrations vary between 1.88 to 6.25 μg g?1 dry weight (Pb), and from 92 to 178.9 μg g?1 dry weight (Zn). These levels differ by site and species. The calculation of the bioconcentration factor (BCF) leads us to conclude that algae bioaccumulate significant levels of Pb and Zn metals in their tissues. Our results shows that the species of C. officinalis bioaccumulate the metals Pb and Zn more than U. lactuca, where, high biosorption of Zn was observed with BCF values between 203.21 and 238.40. Zn content in seawater and algae tissues appear higher than standards set by USEPA and guides values of Certified Reference Materials, but Pb levels appear lower than this standard.  相似文献   

5.
Sludge reed beds have been used for dewatering (draining and evapotranspiration) and mineralisation of sludge in Europe since 1988. Although reed beds are considered as a low cost and low contamination method in reducing volume, breaking down organic matter and increasing the density of sludge, it is not yet clear whether this enhanced biological treatment is suitable for degradation of organic micro-pollutants such as personal care products. Within this project the effect of biological sludge treatment in a reed bed on reducing the concentrations of the fragrances HHCB, AHTN, OTNE was studied as on the bactericide Triclosan. Additionally, the capacity of different macrophytes species to affect the treatment process was examined.Three different macrophyte species were compared: bulrush (Typha latifolia), reed (Phragmites australis) and reed canary grass (Phalaris arundinacea). They were planted into containers (lysimeters) with a size of 1 m × 1 m × 1 m which were filled with 20 cm gravel at the bottom and 50 cm sludge on top, into which the macrophytes were planted. During the twelve months experiment reduction of 20-30% for HHCB and AHTN, 70% for Triclosan and 70% for OTNE were determined under environmental conditions. The reduction is most likely due to degradation, since volatilization, uptake into plants and leaching are insignificant. No difference between the containers with different macrophyte species or the unplanted containers was observed. Considering the usual operation time of 10 years for reed beds, an assessment was made for the whole life time.  相似文献   

6.
Concentrations of 23 elements (Be, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Pd, Cd, Sn, Pt, Pb) were evaluated in whole blood samples of live harbor seals (Phoca vitulina) from two different locations in the Wadden Sea, the Lorenzenplate in Germany, and the Danish island R?m?. Elemental blood levels were compared to data from literature of seals, other marine mammals and humans. While homeostatically controlled elements showed no differences, concentrations of As, Cr, Mn, Mo, Se, and V were higher than human levels. Furthermore, animals from both locations showed significant geographical differences in whole blood concentrations of Al, Mn, Cu, and Pt. These findings could be explained by differences in feeding areas. The element pattern was not affected by gender. In conclusion, these findings indicate an impact of the environment on biochemical blood parameters of the harbor seals. The significant differences of elements in blood samples of two groups of seals, which were associated with geographical variations of prey support the use of element pattern in blood as tool for investigation of environmental impact on seals.  相似文献   

7.
8.
Diatomaceous soils are comprised of the silica frustules of diatom microalgae that are present in marine and lacustrine environments throughout the world.Owing to their unique origin,diatomaceous soils are typically characterized by high intraparticle porosity,complex particle shapes,and uniform mineralogy,causing them to exhibit atypical physical and engineering behaviors.A substantial deposit of diatomaceous silt was observed during site exploration for construction of the Buck Creek Bridge on OR140 near Klamath Falls,OR,USA.A comprehensive laboratory and in situ testing program indicated that the diatomaceous soil possessed“non-textbook”engineering properties.Specifically,tested samples had high liquid limits(≈100%-140%)with natural water contents at or near the liquid limit.Geologically,the soil is expected to be normally consolidated,yet high apparent overconsolidation ratios(OCR)(≈15-40)were observed both in oedometric consolidation tests and through cone penetration test(CPT)correlations.Standard penetration test(SPT)results show a corrected standard penetration resistance consistent with a medium-dense sand(i.e.(N1)60≈25).CPT results include corrected tip resistances(qt)of approximately 7-10 MPa and excess pore pressures(u2)of up to 4 MPa.In CPT dissipation tests,pore water pressures(PWPs)returned to hydrostatic pressure in less than 1 h.In this work,we synthesize these seemingly disparate material properties in an attempt to infer appropriate engineering properties for the diatomaceous deposit at the Buck Creek Bridge and attempt to provide insight into the underlying reasons for the observed behavior.  相似文献   

9.
介绍了场馆建筑的噪声控制标准,并分析了通风空调系统噪声和振动的产生机理及不利影响,给出了基本的设计方法.  相似文献   

10.
The paper gives consideration to the experience of carrying out a short-term (one-moth) geoecological investigation in the territory of Comune di Grosio (Northern Italy). The investigations were aimed at: estimating the geoecological conditions of the given territory and building up cartographic models showing the character, degree and scale of pollution of surface waters, soil, bottom sediments and vegetation; geochemical estimate of water resources used for engineering and drinking water supply; compiling a schematic map of the location of architectural and historical monuments, and their inventory; estimating the decorative and building properties of feldspar.  相似文献   

11.
12.
This paper reports on the first National Symposium held in Mainz in March 1984. A review is given of the most important results and evaluations of future developments and research on the themes of separation of adjacent layers; filtration and drainage in hydraulic engineering; coastal protection, bond and stabilising effects in reinterred soils, dam foundations, roads and railways.  相似文献   

13.
Yue W  Li X  Liu J  Li Y  Yu X  Deng B  Wan T  Zhang G  Huang Y  He W  Hua W  Shao L  Li W  Yang S 《The Science of the total environment》2006,368(2-3):916-925
PM(2.5) samples were collected simultaneously at three representative areas (central city, industrial area and clean air suburban) of Shanghai City. Their morphologies and elemental compositions were determined by scanning electron microscopy coupled with energy analysis (SEM-EDX). The particles were classified into four groups based on morphology and elemental composition. Soot aggregates and spherical fly ash particles were the two dominant types and they were identified as originating from automobile exhaust, metallurgical industry and coal combustion. The size distribution of the particles showed that most had diameters in the range of 0.2-1.4 microm. Individual particles were measured by synchrotron radiation micro-beam X-ray fluorescence (micro-SXRF) and the micro-SXRF spectra were obtained. Pattern recognition techniques, which took the micro-SXRF spectrum of a single aerosol particle as its fingerprint, were used to identify the origins of the particles. Seven source types were identified. They were: metallurgical industry, vehicle exhaust, soil dust, coal combustion, diesel exhaust, oil combustion and motorcycle exhaust. Metallurgical industry, automobile exhaust, and coal combustion were recognized to be the main pollution sources of PM(2.5) in the air of Shanghai City.  相似文献   

14.
There is growing concern about environmentally released man-made chemicals suspected to be responsible for a number of adverse effects on endocrine function in wildlife species and possibly also in humans. Sex hormones are of particular interest due to their regulatory role in developmental processes such as sexual differentiation. Endogenous hormones of human or animal origin as well as exogenous sex steroids used for contraception or as anabolics for farm animals are excreted and reach the environment. We investigated the transport of the synthetic growth promoters trenbolone (TbOH) and melengestrol acetate (MGA) in agricultural soil by means of column experiments with aggregated soil materials (Ap and Bt horizons of a Luvisol). Column effluent concentrations and depth profiles of TbOH and MGA were determined with sensitive enzyme immunoassay systems and HPLC (RP-18), respectively. All procedures were confirmed by liquid chromatography-mass spectrometry. Small amounts of TbOH and MGA passed the columns very quickly. However, both hormones exhibited a high affinity to the organic matter of both horizons leading to a high retardation within the upper layers of the soil columns. Although we cannot deduce whether hormones of animal origin reach the ground water under field conditions, our model experiments show that their transition can be presumed.  相似文献   

15.
基于兰州地区离石黄土(Q2)地基土的室内、原位测试试验成果,对其湿陷性、承载力等工程性质以及岩土参数评价进行了讨论,结果表明:兰州地区离石黄土(Q2)湿陷起始压力大于建筑物基底压力,为一般高层建筑物基础的良好地基。  相似文献   

16.
This study investigates the potential of ZVI on Cd(II) contaminated soil remediation through laboratory experiment, mechanism study and field application. The results show that the dosage of ZVI, the initial concentration level and the reaction time have significant impacts on Cd(II) adsorption and about 88% of aqueous Cd(II) can be removed from soils. The ZVI is observed to promote the increase of Cd(II) residual fraction in Cd(II) contaminated soils according to the sequential extraction procedure (SEP) results. Regression of the laboratory experimental data based on the Langmuir isotherm equation shows the adsorption capacity can reach 34.7 mg/g. Such a high value is attributed to physical and chemical adsorption, which is proved by X-ray diffraction patterns (XRD), scanning electron microscope images (SEM), and Brunner-Emmet-Teller & Barret–Joyner–Halenda (BET-BJH) analysis. The field application shows that the ZVI can reduce the Cd(II) content in soils and brown rice by 51% and alleviate soil acidification, resulting in a 9.4% increase in rice yields.  相似文献   

17.
Ambient measurements (gas+particle phases) of 15 polycyclic aromatic hydrocarbons (PAHs), 17 nitrated PAHs (NPAHs) and 9 oxygenated PAHs (OPAHs) were carried out during July 2004 on three different sites (urban, sub-urban and rural) in the region of Marseilles (South of France). Atmospheric concentrations of these classes of polyaromatics are great of interest because of their high potential mutagenicity and carcinogenicity. OPAH concentrations were of the same order of magnitude as those of PAHs while NPAH concentrations were one to two orders lower. 9-Fluorenone and 9,10-anthraquinone were the most abundant OPAHs, accounting for about 60% and 20% of the total OPAH concentration. Respectively 1-and 2-nitronaphthalene were the most abundant NPAHs and were accounting for about 30-50% and 15-30% of the total NPAH concentration. NPAHs and OPAHs concentration levels were consistent with the characteristics of the sampling sites. Study of source specific ratios (2-nitrofluoranthene/1-nitropyrene) clearly showed those primary NPAH sources influence the urban and sub-urban sites whereas production of secondary NPAHs by gas phase reactions was prevalent at the rural site. The study of NPAH and OPAH sources suggested that gasoline engines were an important source of such compounds Whereas the dominant source of 1-nitropyrene, 2-nitrofluorene, 6-nitrochrysene and benz[a]anthracene-7,12-dione seems to be diesel vehicles. Finally, 9,10-anthraquinone presents a double origin: primary diesel emission and photochemical processes. Formation of 9,10-anthraquinone from anthracene ozonation was shown at the rural site. Further investigations will be necessary in order to discriminate when (before or during the sampling) the OPAHs are formed.  相似文献   

18.
We determined lead concentrations in antlers (n = 132) of roe bucks > or = 2 years of age, killed between 1951 and 1999 in the northern Ruhr area, Germany. The lead content of the antlers ranged between 0.6 and 19.0 mg/kg dry weight of bone, and overall markedly declined over the study period. As a consequence, mean lead levels in younger samples were always significantly (P<0.001) lower than those in older ones (for the periods: 1951-1969, 1970-1979, 1980-1989 and 1990-1999). Annual mean antler lead concentrations were positively correlated (r(s) = 0.74, P<0.001) with annual mean lead concentrations in airborne particulate matter of the Rhine-Ruhr area during the period 1974-1999. The findings of the present study underscore that roe deer antlers are well suited for a monitoring of temporal trends in environmental lead levels in a cost-effective way.  相似文献   

19.
结合某住宅小区(群体)工程施工,对BIM技术在辅助图纸会审、增强施工方案指导性、完善施工图、施工现场模拟、标准化构件应用、工程算量等方面的实际应用进行了研究探讨,以供参考。  相似文献   

20.
This paper uses simple mathematical models to examine the long-term dynamic consequences of the 1988 epizootic of phocine distemper virus (PDV) infection in Northern European common seal populations. In a preliminary analysis of single outbreaks of infection deterministic compartmental models are used to estimate feasible ranges for the transmission rate of the infection and the level of disease-induced mortality. These results also indicate that the level of transmission in 1988 was probably sufficient to eradicate the infection throughout the Northern European common seal populations by the end of the first outbreak. An analysis of longer-term infection dynamics, which takes account of the density-dependent recovery of seal population levels, corroborates this finding. It also indicates that a reintroduction of the virus would be unlikely to cause an outbreak on the scale of the 1988 epizootic until the seal population had recovered for at least 10 years. The general ecological implications of these results are discussed.  相似文献   

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