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131.
S. Cecchini G. Giacomelli D. Haşegan G. Mandrioli O. Mariş L. Patrizii A. Plaian V. Popa L. Ştefanov V. Văleanu 《Astrophysics and Space Science》2000,273(1-4):35-41
The solar neutrino problem could arise from oscillation of one neutrinotype into a secondtype. Neutrinos would have a mass and there could be the possibility ofradiative neutrino decays. We discuss the search for neutrino decaysduring the 1999 solar eclipse: it involves the emitted visible photons,while neutrinos travel from the Moon to the Earth. The concept and themain characteristics of the NOTTE experiment are presented. 相似文献
132.
Moulay?Sma?ne?GhembazaEmail author Said?Ta?bi Jean?Marie?Fleureau 《Arabian Journal of Geosciences》2015,8(6):3365-3380
The study of the temperature effects on the behaviour of saturated and unsaturated soils on triaxial paths requires the development of a new triaxial experimental device of 3.5 MPa of confining pressure and equipped with a heating collar-controlled temperature. In addition to this case of the unsaturated soils, a special pedestal is developed, so as to impose suctions up to 9 MPa using an osmotic solution of polyethylene glycol (PEG) 6000 through a permeable semi-membrane. Measurements of the degree of saturation and the variation of volume during tests induce various problems, primarily related to the thermal dilation of the osmotic solution and the cell-water system. These problems have been solved by carrying out a preliminary calibration. The applicability of this new apparatus concerns environmental geotechnics and geological engineering such as the design and behaviour of engineered barriers as well as the behaviour of the receiving layers of storage sites like radioactive waste. 相似文献
133.
In this study, the decolorization, dearomatization, and mineralization efficiencies of different advanced oxidation processes (AOPs; namely O3, O3/Fe(II), O3/Fe(II)/UVA, and O3/TiO2/UVA) were investigated for the azo dye C.I. Reactive Red 194 (RR194). The effects of pH (3–11), amount of TiO2 (0.05–1 g/L), and concentration of Fe(II) (0.1–1.6 mM) were investigated for the applied methods. The decolorization and mineralization efficiencies of the photocatalytic ozonation system (O3/TiO2/UVA) were increased by decreasing the pH of the dye solution in contrast to the ozonation system (O3). Decolorization of RR194 was increased in the photocatalytic ozonation system with an increasing amount of catalyst however, a decreasing was occurred for the homogeneous catalytic system (O3/Fe(II)) when increasing the concentration of catalyst. The decolorization efficiency of the homogeneous catalytic system (O3/Fe(II)) was enhanced when combined with UVA light. In our study, the most efficient method for dearomatization and mineralization was the O3/TiO2/UVA among the applied AOPs. 相似文献
134.
Ta Liu 《中国地理科学(英文版)》1994,4(3):219-231
刘塔URBANRENEWALANDDEVELOPMENTOFSHANGHAICITY¥LiuTa(NanjingInstituteofGeographyandLimnology,theChineseAcademyofsciences,Nanjing2... 相似文献
135.
136.
Hüseyin Çaldırak Bedri Kurtuluş 《Journal of the Indian Society of Remote Sensing》2018,46(9):1353-1364
This study explores the evidence of recharge locations using hydrogeochemical and physicochemical measurements in an alkaline lake, Lake Salda, in Burdur, Turkey. In-situ measurements have been performed using a conductivity–temperature–depth device to map the physicochemical dynamic of the lake. Water and sediment samples were collected on the surface and floor of the lake. A seismic study was also carried out in order to observe the geometry of the lake floor. In addition, thermal distribution was mapped using the thermal band of Landsat 7 ETM+ and Landsat 8 satellite images. Temperature and specific conductance measurements were mapped using a new technique, Empirical Bayesian Kriging (EBK), from the lake’s surface to the floor. According to interpolation maps obtained from the EBK, possible water inputs were observed close to a fault at the south-eastern part of the lake. The results of thermal band imaging also reveal the probability of a fault effecting the recharge on the surface. The results of water and sediment samples present a richness in Mg2+ and Fe2+ elements respectively on the floor of the lake. Finally, seismic results show some possible recharge zones on the floor of the lake, and sediment results indicate that there should be peridotite occurrence below the alluvium unit. 相似文献
137.
M. Răcuciu C. Iftode S. Miclăuş 《International Journal of Environmental Science and Technology》2018,15(6):1233-1242
The biological impact of microwaves exposure on biosphere is presently an important research subject. With the significant increase of communications technology use, of industrial and military activities which involve radiofrequency radiation, electromagnetic pollution became very intense in the last years. The aim of the present work was to investigate the genotoxic influence of microwaves on Zea mays seeds. They were exposed in controlled conditions for different durations at 1 GHz continuous wave providing a low specific absorption rate of energy. Post-exposure the mitotic- and chromosomal aberrations indexes were determined. Qualitatively, a wide range of abnormal mitotic stages were detected in cells of exposed seeds in comparison with the control. Quantitatively, slight stimulatory effect on mitotic division process, expressed by an enhanced percentage of dividing cells (increased of 26% for 180 min exposure), for all exposed samples was revealed, while lowered level of induced chromosomal aberrant cells percentage (up to 2.14%) was also found. The aberrations percentage and mitotic index increased in time-dependent manner on exposure dose. 相似文献
138.
Halil İbrahim Gülşen-Rothmund Özgür Avşar Ulaş Avşar Bedri Kurtuluş Evren Tunca 《Environmental Earth Sciences》2018,77(14):546
Elemental accumulation, distribution and relationship profiles for sediment samples taken at 81 localities in the Köyce?iz Lake were investigated. Spatial distribution maps for ten elements (Cu, Pb, Zn, Ni, Cr, Co, Mn, Mo, Al, Fe) were created using the ordinary kriging interpolation method. Statistical tests revealed that the sediments taken from areas close to the Namnam (NamSM) and Karg?cak (KarSM) stream mouths have the highest element content. In addition, sediments close to NamSM have the highest contamination, according to contamination degree and modified contamination degree values. On the other hand, sediments close to KarSM have the highest value on the pollution load index. The enrichment factor and contamination factor values of Cr and Co, and especially Ni, close to NamSM are striking and have significantly higher values compared to the rest of the lake. There are strong correlations between these three elements, which were also confirmed by cluster analysis. Ni is the element having the highest value on the geoaccumulation index. In addition, according to the toxic unit results, it was found that 84–89% of the element-based toxic effect in the lake is due to Ni alone. According to the mean effect range median quotient values, the sediments of Köyce?iz Lake have a potential to show toxic effects of at least 76% in living organisms, which is due to the high levels of Ni. According to the mean probable effect low quotient value, it has been determined that Köyce?iz Lake is at a “highly impacted” level, which is the worst possible value on the quality scale. 相似文献
139.
Delineation of the groundwater potential zones is one of the most essential process for the sustainable management of the groundwater sources. However, groundwater studies are quite hard and complex for many regions besides consuming time and cost. This study focused on the groundwater potential mapping in Bey?ehir Lake Basin. Mainly, fuzzy-analytic hierarchy process (fuzzy-AHP) integrated with GIS was used to determine potential zones for groundwater. Seven parameters, namely lithology, lineament, drainage density, land use, slope, soil type, and rainfall were evaluated and Groundwater Potential Index (GWPI) was calculated using weight and rating coefficients of each parameter. According to obtained results, GWPI varies from 0.07665 to 0.28243 in the basin. The low, moderate, and high groundwater potential classes were determined with quantile classification method. The groundwater potential map demonstrates that the high groundwater potential area is located around the lake shore, in the alluvium and limestone fields because high permeability rates depend on soil type, low slope, karstic structure, and agricultural activities in these regions. In addition, the distribution of the springs confirms with groundwater potential area determined with this study. 相似文献
140.
In the Pötürge (Malatya, Turkey) area pyrophyllite occurrences are common in the shear zones, mostly in the form of lenses along faults. Mineralogical investigations (XRD, FTIR and SEM) revealed that pyrophyllite, kaolinite (dickite) and quartz are present in the form of major phases and muscovite (sericite), kyanite, chlorite, and alunite are only present in the form of minor phases. This study revealed that the existence of the kyanite phase points out to high pressure and temperature conditions which the rocks were underwent. On the other hand, the minerals such as pyrophyllite, kaolinite, and alunite are products of a low degree metamorphism (retrograde). The mineral paragenesis in the pyrophyllite deposits suggests that the formation of minerals took place in two ways: (1) the transformation of kyanite into pyrophyllite and quartz through retrograde metamorphism by a high degree temperature, (2) then pyrophyllite and probably muscovite were transformed into kaolinite and alunite through reactions with relatively low temperature hydrothermal fluids. The geochemical data indicate that during the retrograde metamorphism the elements K, Rb, Sr, Ba, S, and Fe were mobile, the elements Si, Al, P moderately mobile to immobile and the HPS elements (Zr, Ti, and Nb) were immobile. It was shown that the formation of pyrophyllite, kaolinite and alunite was associated with depletion in alkalis, Mg, Fe and enrichment of elements including Sr, Ba, and S. Mineralogical and geochemical data suggest that parent rocks (pre-metamorphism) of the Pötürge pyrophyllite were probably kaolinite, Al-rich clays or bauxites. 相似文献