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Placer-Forming Cenozoic Mud-Volcano Genetic Type of Gold Mineralization in the Lena Area, Patom Highland, Russia
Get PDFA genetic type of Cenozoic gold mineralization related to mud volcanoes is suggested to be recognized in the Lena area. This type of mineralization has never before been distinguished in the area and is genetically related to the development of depression mud-volcano structures on the northern continuation of the Baikal rift. Geological-geophysical data and results of lithological-petrographic and mineralogical studies of the mud-volcano lithological complex, naturally occurring microscorias, and ore minerals from the loose Quaternary rocks, as well as and comparison of the chemical composition of the latter with analogous minerals from the Sukhoi Log and Pervenets gold deposits, prove genetic links of economic placer deposits in the Lena area with mud volcanoes
Spatial Variation of Textural Parameters in a Small River: An Example from Khurar River, Khajuraho, Chhaterpur District, Madhya Pradesh, India
Get PDFTexture (grain size) is one of the many parameters, which is used in determining depositional environments of sediments and sedimentary rocks. In the present investigation, texture was analysed from sixteen stations in the Khurar River, Madhya Pradesh, India. Here, grain size analysis was carried out employing mechanical sieving method using a sonic shaker. Frequency and cumulative frequency curves were prepared from the grain size data on centimetre and arithmetic probability papers, respectively. The phi values were determined and used to calculate the statistical parameters such as mean, standard deviation, skewness and kurtosis. It is found that the mean size value varies from-0.63to 0.80 with a graphic mean distribution ranging from -0.27 to 0.40 ϕ, indicating that the size of the river sand is very coarse to coarse-grained. The standard deviation (sorting) shows a range of 0 .69 to 1.65 ϕ. The skewness values of the sediment samples range from 0.19 to 0.29 ϕ, thus, indicating the presence of fine fraction to near-symmetrical fraction in the population. The kurtosis varies between 1.03 and 1.09 ϕ, indicating that 25% of the samples are leptokurtic, 6.25% are very leptokurtic, 50% are mesokurtic and 12.5% are platykurtic. The platykurtic nature in few cases suggests mixing of sediments from two sources. Bivariate plots prepared combining various textural parameters were used to interpret their behaviour in the river sediments. C-M plot was also prepared to understand the dominant mode of sediments transportation in the Khurar River. In this river, all the sediments are dominantly characterized by the rolling process of transportation. This study reveals that sorting varies from poorly sorted to moderately well sorted in the course of the river may be because of dominance of winnowing and selective sorting in the lower reaches of the river
Nuclear Systems for Hydrogen Production: State of Art and Perspectives in Transport Sector
Get PDFA technologically feasible transition towards a realistic and sustainable hydrogen economy (i.e. on large scale and without carbon dioxide emissions) could be made through the use of nuclear energy. In fact, nowadays hydrogen production methods without the employment of fossil fuel represent only a low share of the total production; but the use on large scale of hydrogen produced by “carbon-based†sources is neither environmentally nor economically meaningful.In the present paper, besides a deep evaluation of the state of art of hydrogen production methods via nuclear source, it has been proposed an energy scenario analysis (based on the hydrogen produced by the thermo-chemical Iodine-Sulfur process fed by High Temperature Gas Reactor (HTGR) included in a symbiotic nuclear fuel cycle), focused on the China region, that would meet the sustainability criteria in both the energy and environmental domains for transport sector
The Influence of Religious and Cosmological Beliefs on the Solar Architecture of the Ancient World
Get PDFIn the earliest civilizations of the Ancient World, sun worship developed in parallel with an understanding of the movement of the stars. That was the origin of an architecture that expressed a number of religious and cosmological beliefs. Studies of ancient archaeological remains have revealed that astronomical orientations strongly influenced the construction of some of the most important ancient architectural monuments.Besides its religious role, the sun regulated the culture of the Ancient World in many of its more practical aspects. For instance, the observation of solar and lunar cycles allowed people to anticipate seasonal change. This provided man with a means of organizing and improving agricultural and livestock activities and, in turn, influenced the construction of the large civil and religious buildings.The complex relationships that developed between cosmology, sun worship, early mathematics, and the orientation of buildings with respect to the position of the sun, also decisively influenced the birth and development of what has come to be known as passive solar design.This article describes some of these influences dating from the megalithic period to the development of Mesopotamian and Egyptian architecture
Le Corbusier’s Modern Museum Prototype: The Transformation of Unlimited Growth Museums
Get PDFThis paper analyzes how Le Corbusier constructed the prototype of the modern museum according to the concept of Unlimited Growth, and how he interpreted and implemented the prototype in three museums. Through analyzing and comparing the development of the concept of Unlimited Growth and its implementation across three aspects of design, namely modules, space arrangements, and natural lighting, we noticed that Le Corbusier did not limit his design thinking to mere prototypes; instead, through the implementation process, he redefined the core design of the modern museum by transferring the focus from Unlimited Growth to lighting design, which would later become one of the key design issues of contemporary museum design
DNA Contents in Soil Contaminated with Heavy Metals
Get PDFThe study was performed to show how industrial activity affected soil quality in terms of soil DNA quality and quantity as well as soil characteristics. Soil material originated from an urban area of the Silesia Region (SW Poland). The soil characteristics were estimated: texture, moisture, pH, redox potential (Eh), and total carbon content (TOC), followed by determination of selected heavy metals (Pb, Cd, Zn, Cr, Fe, Cu). The last step was the isolation of soil DNA, its concentration and identification of microorganisms. The results showed that although the studied soil was heavily contaminated with heavy metals, there were still some metal-resistant microorganisms able to sustain soil activity. Moreover, these organisms are not present in the NCBI database, which encourages further studies aimed at identification of new organisms that may be useful in research of metal resistance as well as soil reclamation and remediation
Frost Heave and Ice Lenses Formation in Freezing Soils
Get PDFA generalized model for secondary frost heave in freezing fine-grained soils is presented and discussed. The cryostatic suction effect, which increases upward water permeation, ice-lens growth during freezing, and, as a consequence, the increase of soil heave, is considered to be the main mechanism of moisture transfer. We recognize the need to determine the distribution of the moisture within the frozen fringe by approximation of the experimental data for the equilibrium unfrozen water content. This distribution is the result of the complicated interaction between water, ice and the mineral skeleton during the freezing process. The generalization of the Clapeyron relation, which is used in the studies of other authors, estimates only the drop in initial freezing temperature and does not define the connection with the external temperature gradient ∆T, which is responsible for the frost heave process. This very important aspect is discussed in detail in the introduction to our paper. We take also into account the ratio Pe/Ste # 1 (where Pe<<1). This approach allows us to obtain a more general solution. The criterion of the ice lenses formation in fine-grained soils and the model for calculation of the lenses' thickness and spacing are derived. The dynamics of the lenses formation in histogram form is presented and discussed. The theoretical results obtained from the solution for fine-grained soils are compared in good agreement with experimental investigations. The model presented predicts the frost heave and ice lenses formation in freezing soils with reasonable accuracy, satisfactorily reflects observed phenomena, and thus can be suitable for engineering practice
Carbonization Kinetics of Various Biomass Sources
Get PDFHazelnut shell, apricot stone, grapeseed and chestnut shell samples were carbonized in a thermogravimetric (TG) analyzer at different conditions to determine the carbonization kinetic parameters. Three different calculation methods and 22 different model equations concerning solid-state rate controlling mechanisms were used for the kinetic analysis of the carbonization TG curves. A computer program in BASIC which enables regression analysis, was used to calculate the kinetic parameters from experimental TG data. It was observed that the different values of Arrhenius parameters (E and Log A) were obtained depending on the method of calculation, the gaseous atmosphere and the sample properties. The most appropriate kinetic model which represents the carbonization of the cellulosic and lignin ingredients of the biomass samples were found as f(α)=(1−α)2 and f(α)=0.5·(1−α)·[−ln(1−α)]−1, respectively