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61.
Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments formed in different marine(with normal and reduced salinity),brackish,and freshwater environments,depending on the development stage of the Pannonian Basin System.Carbonate minerals,clay minerals and quartz are the main constituents of all pelitic sedimentary rocks,except in those from Moslavacka Gora Mt in which carbonate minerals are not present.Feldspars,pyrite,opal-CT,and hematite are present as minor constituents in some rocks.Besides calcite,dependent on the sedimentary environment and diagenetic changes,high-magnesium calcite,aragonite,dolomite and ankerite/Cadolomite are also present.Smectite or illite-smectite is the main clay minerals in the samples.Minor constituents,present in almost all samples,are detrital illite and kaolinite.In some samples chlorite is also present in a low amount.Major elements,trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust(UCC).The contents of major and trace elements as well as SiO_2/Al_2O_3,K_2O/Al_2O_3,Na_2O/K_2O,Eu/Eu~*,La/Sc,Th/Sc,La/Co Th/Co,Th/Cr,Ce/Ce~* and LREE/HREE ratios,show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic(silicic),i.e.felsic rocks. 相似文献
62.
63.
Petar B. Dokmanovi? Zoran N. Niki? Olivera Z. Kruni? Branislav Z. Petrovi? 《Hydrogeology Journal》2012,20(6):1169-1175
The design of the Rovni Lake reservoir in the Kolubara District, western Serbia, is the basis for the regional water-supply system there. The design was promoted as an example of integrative and sustainable water management, with regard to the planned provision for long-term municipal water supply in the Kolubara region, as well as for the regulation of the downstream river flow. Hydrogeological analyses, however, have indicated three key issues that contest this sustainable water-management model: (1) the capability of the available groundwater sources to fully meet the drinking water demands in the region, (2) a pronounced risk of water loss from the reservoir, and (3) a pronounced risk of karst aquifer contamination. The Rovni project ignores the hydrogeological properties of a karst aquifer and thereby needlessly threatens the groundwater resource. Hence, modifications to the project are recommended in order to mitigate or eliminate the most significant construction and ecological risk factors and to improve sustainable exploitation and integrative water-resource management. 相似文献
64.
The recharge of a karst aquifer, in terms of its quantity and spatial distribution, depends on various natural factors such
as climate, topography, vegetation, soil, and geology. Selection of an adequate method for assessing recharge in karst is
often a matter of dispute. Multi-parameter methods using Geographical information systems tools have recently been successfully
developed and applied in karstic terrains of Spain and Lebanon. Specific local conditions such as highly karstified terrains
could additionally complicate such an assessment. The Montenegro karstified terrains in the southern part of the External
Dinarides are characterized by a very high precipitation rate, irregular seasonal distribution, and absence of surface waters
(extremely high infiltration capacity of karst). Considering such conditions, an attempt to apply existing knowledge and experiences
to the development of an appropriate multi-parameter method for assessing spatial distribution of autogenous recharge has
been made. The KARSTLOP method has been developed, applied, and calibrated at catchments of several large karst springs of
Montenegro. Obtained results in tested catchment areas confirm that with some further improvements the KARSTLOP method could
be a useful tool to support research of karstic aquifers in similar highly karstified terrains. 相似文献
65.
Darka Marković Bojan Jokić Zoran Šaponjić Branislav Potkonjak Petar Jovančić Maja Radetić 《洁净——土壤、空气、水》2013,41(10):1002-1009
This paper discusses the possibility of immobilization of TiO2 nanoparticles onto recycled wool‐based nonwoven material, which can be utilized for removal of dyes from wastewater. The photocatalytic activity of TiO2 nanoparticles deposited on the nonwoven material was evaluated in the aqueous solution of direct dye C.I. Direct Blue 78 under the UV illumination. Nonwoven material modified with TiO2 nanoparticles provides complete removal of dye from the solution already after 4–6 h of UV illumination. However, photodegradation of the dye adsorbed on the nonwoven material was obtained within 24 h of UV illumination. The rate of dye adsorption and photodegradation depends on the amount of deposited TiO2 nanoparticles. The increase of initial dye concentration induced decrease in photocatalytic efficiency of immobilized TiO2 nanoparticles. The highest photodegradation rate was achieved in acidic conditions. Elevated temperatures positively affected the removal of dye from solution. Photocatalytic activity of TiO2 nanoparticles deposited on nonwoven material was preserved after three photodegradation cycles. 相似文献
66.
Massimiliano Guzzo Zoran Knežević Andrea Milani 《Celestial Mechanics and Dynamical Astronomy》2002,83(1-4):121-140
We apply the spectral formulation of the Nekhoroshev theorem to investigate the long-term stability of real main belt asteroids. We find numerical indication that some asteroids are in the so-called Nekhoroshev stability regime, that is they are on chaotic orbits but their motion is stable over very long times. We have analyzed the motion of bodies in different regions of the belt, to assess the sensitivity of our method. We found that it allows us to clearly discriminate between different dynamical regimes, such as the one described by the Nekhoroshev stability, the one well described by the KAM theory, and the unstable chaotic regime in which diffusion in phase space can be detected over time spans much shorter than the age of the solar system. 相似文献
67.
Linda Sorg Neiler Medina Daniel Feldmeyer Arlex Sanchez Zoran Vojinovic Jörn Birkmann Alessandra Marchese 《Natural Hazards》2018,92(1):257-282
Vulnerability and disaster risk assessment has been evaluated from different perspectives with focus on global or national scale. There is a lack of methodologies on city scale, which are able to capture inner-city disparities with regard to socioeconomic aspects. Therefore, the main objective was to develop a transparent and comprehensive indicator-based approach which is flexible in terms of data availability and is not tied to a specific case study side. This research proposes two flexible methodological approaches on how to perform socioeconomic vulnerability assessment. Susceptibility, Coping and Adaptation are the main elements of a modular hierarchical structure to capture the societal sphere of vulnerability. The first method is completely based on official census data at block scale. The second method is an expansion and includes data derived from a field survey to add components of risk perception. The proposed methodologies were developed and applied in the city of Genoa (Italy). The results are displayed spatially explicit on maps. Furthermore statistical analysis, to reveal the driving forces which influence vulnerability, was performed. The census-based approach revealed that vulnerability is forced along the river by the inherent susceptibility, as well as the lack of adaptation. The two approaches can be used effectively in gaining different insights. The flexibility of the framework proved to be suitable to the objective of the research. However, the values computed in this research do not claim completeness, and the aim was to provide useful information for stakeholders in decision making process to reduce vulnerability and risk. 相似文献
68.
The concentrations of air pollutants depend on meteorological conditions and pollutant emission level. From the statistical properties of air pollutants the number of times the daily average concentrations exceed the assigned air quality standard (AQS) can be estimated, as well as the level of reduction of particle matter emission sources required to meet the AQS. In this paper three statistical distributions (lognormal, Weibull and type V Pearson distribution) were used to fit the complete set of PM10 data for the Belgrade urban area during a three-year period (2003–2005). The method of moments and the method of least squares were both used to estimate the parameters of the three theoretical distributions. The type V Pearson distribution represented the PM10 daily average concentration most closely. However, the parent distributions sometimes diverged in predicting a high PM10 concentration and therefore asymptotic distributions of extreme values were used to fit the high PM10 concentration distribution more correctly. This method can successfully predict the return period and exceedances over a critical concentration in succeeding years. The estimated emission source reduction of PM10 to meet the assigned standard varied from 53% to 63% in the Belgrade urban area. The results provide useful information for air quality management and could be used to examine the similarities and differences among air pollution types in diverse areas. 相似文献
69.
Anna M. Nobili Gian Luca Comandi Suresh Doravari Donato Bramanti Rajeev Kumar Francesco Maccarrone Erseo Polacco Slava G. Turyshev Michael Shao John Lipa Hansjoerg Dittus Claus Laemmerzhal Achim Peters Jurgen Mueller C. S. Unnikrishnan Ian W. Roxburgh Alain Brillet Christian Marchal Jun Luo Jozef van der Ha Vadim Milyukov Valerio Iafolla David Lucchesi Paolo Tortora Paolo De Bernardis Federico Palmonari Sergio Focardi Dino Zanello Salvatore Monaco Giovanni Mengali Luciano Anselmo Lorenzo Iorio Zoran Knezevic 《Experimental Astronomy》2009,23(2):689-710
“Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which
is at the basis of the General Theory of Relativity—to 1 part in 1017. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain
theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried
out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase
A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG)
is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study
report will be published in 2009. 相似文献
70.
Karst aquifers represent one of the main sources of water supply in Serbia. Wide distributions of karstic areas, abundant
reserves, and excellent quality of karst groundwater have been the reasons for its extensive use in water supply systems throughout
the country. In Serbia, 70 karstic sources have been tapped for centralized water supply, with the assessed minimal capacity
exceeding 4.5 m3/s. Most of the large cities of Eastern and Western Serbia currently use karst groundwater for water supply; however, due
to unstable flow regime when only natural springflow is tapped, numerous problems arise during the recession period (summer–autumn).
During the last two decades, after favorable conditions had been confirmed through hydrogeological survey and feasibility
studies, several newly constructed systems for artificial control of karst aquifers (mostly in Eastern Serbia) resulted in
significantly improved water supply. 相似文献