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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

American Journal of Geoscience

This study deals with the mineralogical, physico-chemical and geotechnical analyses of representative Aptian clays in the north-east of Tunisia. X-ray diffraction reveals a predominance of illite (50-60 wt.%) associated to kaolinite and interstratified illite/smectite. The accessory minerals detected in raw materials are quartz, calcite and Na-feldspar. The average amounts of silica, alumina and alkalis are 52, 20 and 3.5 wt.%, respectively. The contents of lime and iron vary between 4 and 8 wt.%. Physical analyses show that the cation exchange capacity is 34.1-45.7meq/100g of air-dried clay. The plasticity test shows medium values of plasticity index (16-a28 wt.%). The linear drying shrinkage is weak (less than 0.99 wt.%) which makes these clays adapt to fast drying. The firing shrinkage and the expansion are limited. A lower firing and drying temperature can be translated into significant energy savings. Currently, these clays are used in the industrial process for the manufacturing of the earthenware tiles. For the better exploitation of the materials and improvement of production conditions, a mathematical formalism is established for the drying parameters. The regression models relate drying shrinkage (d), bending strength after drying (b) and residual moisture (r) with the moisture (m) and the pressing pressure (p).

http://www.thescipub.com/abstract/10.3844/ajgsp.2014.1.7 2014/07/01 - 12:01

This study deals with the mineralogical, physico-chemical and geotechnical analyses of representative Aptian clays in the north-east of Tunisia. X-ray diffraction reveals a predominance of illite (50-60 wt.%) associated to kaolinite and interstratified illite/smectite. The accessory minerals detected in raw materials are quartz, calcite and Na-feldspar. The average amounts of silica, alumina and alkalis are 52, 20 and 3.5 wt.%, respectively. The contents of lime and iron vary between 4 and 8 wt.%. Physical analyses show that the cation exchange capacity is 34.1-45.7meq/100g of air-dried clay. The plasticity test shows medium values of plasticity index (16-a28 wt.%). The linear drying shrinkage is weak (less than 0.99 wt.%) which makes these clays adapt to fast drying. The firing shrinkage and the expansion are limited. A lower firing and drying temperature can be translated into significant energy savings. Currently, these clays are used in the industrial process for the manufacturing of the earthenware tiles. For the better exploitation of the materials and improvement of production conditions, a mathematical formalism is established for the drying parameters. The regression models relate drying shrinkage (d), bending strength after drying (b) and residual moisture (r) with the moisture (m) and the pressing pressure (p).

http://www.thescipub.com/abstract/10.3844/ajgsp.2014.1.7 2014/07/01 - 12:01

PAHs form one of the most important classes of persistent pollutants. Sediment samples were taken from the eastern Caspian Sea coast of Mazandaran state analyzed by (GC-MS) for PAHs. Sediment samples were collected from eastern part of southern Caspian Sea in Mazandaran Province. Stations were Amirabad (10), Sari (5), Babolsar (5) and Noushahr (5) to determinate distribution and to source of PAHS. We analyzed 8 PAHs such as Benz [a] anthracene, Benz [a] pyrene, Fluoranthene, pyrene, Chrysene, Benz [e] pyrene, Benz [k] Fluoranthene and Benzo [ghi] perylene in this research.Result of this study showed that Concentrations of all PAHs except Pyr, B (a) A and B (a) P in Amirabad are below the concentration to elicit toxic effects in benthic organisms (Effects Range-Low). There was high spatial variability in the PAH concentrations that ranged from 12-453 ng g-1. To elucidate sources, two molecular indices (Pyr/Fluo, BaA/(BaA + Chr) ratios were used to determine the pyrogenic and petrogenic sources. Amirabad-Behshahr region receives input primarily from oil activity; therefore, it can be inferred that the main source of PAH could be petrogenic (Pyr/Fluo = 1.07). The PAH source in Sari is pyrogenic for Neka power plant that uses fossil fuels (BaA (BaA + Chr) = 0.38). Water samples were collected from 20 wells during a period of 1 year. The average Concentrations of diazinon, chlorpyrfos, ethion and edifenphos in the ground waters were 0.018, 0.017, 0.014 and 0.013 µg-1, respectively. This research found that the residues of pesticides are major threat to aquatic life of the regional ecosystems.

http://www.thescipub.com/abstract/10.3844/ajgsp.2013.30.35 2014/06/12 - 22:11

The study of volcano-sedimentary deposits of Mangbai in SE Mayo Oulo basin-Cameroon leads to the identification of five major distinct lithofacies types. From the coarset to the finest lithofacies, there are: Gb-clast supported by massive coble and boulder, Gg-granule to massive gravel, Sm-massive sand, Sh-horizontal layered sandstones, Fml-massive laminated claystones. Coarse facies (Gb, Gg, Sm) are cemented with volcanic matrix while the finest facies (Sh, Fml) are normal sedimentary compacted deposits. The coarsest facies distribution is identified on the top SE of the mountain while the medium to finest facies deposits are located at the base of the sequence. The formation of the volcano-sedimentary deposits of Mangbai are associated to the development and establishment of Africa major rift system while sedimentary deposits in the Mayo Oulo basin are more recent and date from Lower Cretaceous.

http://www.thescipub.com/abstract/10.3844/ajgsp.2013.23.29 2013/12/19 - 15:26

WorldView-2 satellite imagery includes half-meter panchromatic resolution and 2 m multispectral resolution. Because of the reduced dimensions of pixels and articulated spectral acquisition these images supply detailed information that can be used for geoscience applications, above all to investigate areas, identify land cover, bound vegetated zones, outline transformations (change detection). The aim of this study is to remark possibilities to use WorldView-2 imagery for analysis of Phlegrean area (Italy), facilitating monitoring actions and increasing level of knowledge of territorial and environmental features. This area is emblematic for many aspects such as its geological history, the presence of volcanic activities, the Roman ruins and the natural forest. The study is centered on methodological aspects about the use of WorldView-2 imagery for increasing dataset and level of information. For consequence attention is firstly focalized on possibilities to obtain geometrical corrected data with adequate accuracy (comparable to pixel dimensions): using Rational Polynomial Functions for ortho-rectification, references are already georeferred air-photos with cell-size equal to that of WorldView-2 higher resolution images (panchromatic band: 0.50×0.50 m), while Digital Terrain Model (DTM) is built with cartographic dataset in scale 1: 5,000. Then other two methodological aspects on WorlView-2 imagery use are considered: Normalized Difference Vegetation Index (NDVI) application and 3d photo-realistic model construction. In the first case thresholds determination to distinguish vegetated areas is conducted using Maximum Likelihood method based on training sites to achieve high level of thematic accuracy; in the second RGB composition is obtained and overlapped to DTM.

http://www.thescipub.com/abstract/10.3844/ajgsp.2013.1.12 2013/09/05 - 17:52

Chengmenshan Copper SulphurMine, one of the of the large-scale open pit mine in China, the engineering geology and hydrogeology in the Southern slope of the mine is very complicated and the contact plane between two kinds of sandstone’s form soft-weak layer. Field investigations and reports by operators demonstrated that some instability problems might occur in the southern slope which is situated in zone I and zone II. Southern slope was divided into six sections (I-0, I-1, I-2, II-0, II-1 and II-2) to make the analysis. Slope stability analyses using limit equilibrium and numerical showed that the safety factors of some section are very low (section I-0, I-1, I-2) as a result of this, failure is likely to happen. Therefore reinforcement is very important to increase the safety factor of the three sections, two methods were used; Grouting to increase the slope cohesion (c) and Pre-stressed Anchor then the factor of safety increased more than 1.15.

http://www.thescipub.com/abstract/10.3844/ajgsp.2013.13.22 2013/09/05 - 17:52

Problem statement: In this article we considered pairs bootstrap through a truncated geometric bootstrap method for stationary time series data. Construction of valid inferential procedures through the estimates of standard error, coefficient of variation and other measures of statistical precision such as bootstrap confidence interval were considered. The method was used to confirm the correlation between Silicon Oxide (SiO2) and Aluminum Oxide (Al2O3) from a geological data. A typical problem is that can these components exist together or they are mutually exclusive. Approach: We attempt to solve these problems through bootstrap approach to correlation analysis and show that pair bootstrap method through truncated geometric bootstrap method for stationary process revealed the correlation coefficient between Silicon Oxide (SiO2) and Aluminum Oxide (Al2O3) from the same geological field. Results: The computed measure of statistical precisions such as standard error, coefficient of variation and bootstrap-t confidence interval revealed the correlation analysis of the bivariate stochastic processes of SiO2 and Al2O3 components from the same geological field. Conclusion: The correlation analysis of the bivariate stochastic process of SiO2 and Al2O3 components through bootstrap method discussed in this study revealed that the correlation coefficients are negative and bootstrap confidence intervals are negatively skewed for all bootstrap replicates. This implies that as one component increases, the other component decreases, which means that the two components are mutually exclusive and the abundance of one mineral prevents the other in the same oil reservoir of the same geological field.

http://www.thescipub.com/abstract/10.3844/ajgsp.2011.10.12 2013/06/09 - 17:53

Problem statement: Serpentine soils are known as a geogenic source of heavy metal pollution because they are anomalously rich in chromium, nickel and cobalt. Approach: However, only that portion of these metals which is available in the ecosystem and incorporates in the bio-transformation processes, is dangerous for the environment. Availability of Cr, Ni and Co depends on their speciation into the different fractions of a soil and corresponds with their chemical binding forms. Soil is a combination of several reactive fractions which have the ability to interact physically and chemically with heavy metals and changes their existence form in the soil. Results: Thus, understanding the geochemical form and distribution of metals in different fractions of soil is fundamental for predicting the availability and potential toxicity of them under natural condition. Conclusion: This study set out with the aim of fractionation of Cr, Ni and Co in serpentine soils of Ranau in Sabah state of Malaysia. Selective Sequential Extraction analysis (SSE) was combined with X-ray diffraction of soil powders to find the mineralogical source and mobility of Cr, Ni and Co in serpentine soils.

http://www.thescipub.com/abstract/10.3844/ajgsp.2011.4.9 2013/06/09 - 17:53

Problem statement: Serpentine soils are known as a geogenic source of heavy metal pollution because they are anomalously rich in chromium, nickel and cobalt. Approach: However, only that portion of these metals which is available in the ecosystem and incorporates in the bio-transformation processes, is dangerous for the environment. Availability of Cr, Ni and Co depends on their speciation into the different fractions of a soil and corresponds with their chemical binding forms. Soil is a combination of several reactive fractions which have the ability to interact physically and chemically with heavy metals and changes their existence form in the soil. Results: Thus, understanding the geochemical form and distribution of metals in different fractions of soil is fundamental for predicting the availability and potential toxicity of them under natural condition. Conclusion: This study set out with the aim of fractionation of Cr, Ni and Co in serpentine soils of Ranau in Sabah state of Malaysia. Selective Sequential Extraction analysis (SSE) was combined with X-ray diffraction of soil powders to find the mineralogical source and mobility of Cr, Ni and Co in serpentine soils.

http://www.thescipub.com/abstract/10.3844/ajgsp.9.4.9 2013/03/21 - 08:33

With the increasing demand in water supply and either for generation or for irrigation and human consumption, water conveyance structures must guarantee a maximum efficiency at the lowest construction and maintenance costs. Using thin geotextiles allow very low permeability and very high transmissivity. Conclusion/Recommendations: The system constructs a continues, low roughness on the entire section of canal. In this research study the use of geotextile in order to stabilize and increase in shear strength of sandy soils has been investigated. The results show an increase about 44% of shear strength that cause an enhancement of stability of soils.

http://www.thescipub.com/abstract/10.3844/ajgsp.2011.1.3 2012/01/24 - 04:25

Problem statement: In order to assess the applicability of Australian landslide databases as
a hazard management support system, current hard and soft literature and data sources were screened.
This assessment resulted in the selection of four main data bases including national landslide database
(A), Peril Aus ІІ (B), the Cities project (C) and analytical study of Fell (D). Approach: In this study
applicability of databases was evaluated using two different methods: Numerical model (objective) and
AHP model (subjective). After statistical analysis, the results of this evaluation were combined. Due to
shortage of a definite standard, a simple numerical model has been developed with 4 main complex
parameters (each one contains 4 minor parameters). This includes: Graphical-statistics, geo-spatial,
physico-temporal and techno-management, value scale of 0-3 and 4 applicability classes and relative
importance of the databases has been evaluated. Relative priority of the databases as competitor
alternatives was determined using Analytical Hierarchy Process (AHP) technique as a math-logical
tool for decision making in uncertainty, by expert based pair-wise comparison (CR = 0.0296). Finally
its value was normalized to the scale of numerical model for comparison. Results: According to the
results, in both models applicability classes of databases range from II-IV with only one class
difference. With merging numerical outputs of two models by a 80% rank correlation in a single
paradigm, the applicability class improve from ІІ-ІІІ only in database A, but for others remain
constant. Rank correlation between databases in different levels imply to different relationships, so that
some of them such as RAB, RAC, RAD and RBC can be explained with the inductive theorems of
genetically statistic-thematic multi-relations of databases. The differences of strengths and weaknesses
of the Australian four main landslide databases that mainly affect their practical applicability for
hazard management are considerable in spite of genetic relation and data overlaps. Thus, practical
applicability of each database can be characterized well by two contrast objective and subjective
models. Conclusion: As a result, applicability of Australian landslide databases is of class ІІІ (high).
Thus, it still needs further development and complementary actions especially in geo-technical,
geometric, impact (damage) data and map scale.

http://www.thescipub.com/abstract/10.3844/ajgsp.2010.7.11 2011/03/13 - 07:40

Problem statement: Three broad morphological zones and several sub-zones were
differentiated within the weathering profile based on variations in earth materials and the degree of
preservation of original bedrock minerals, textures and structures. Approach: The topmost Zone I
(Grade 6) is some 12 m thick and comprises completely weathered bedrock materials (mainly a stiff,
clayey sand) with indistinct relict bedrock textures. Results: The intermediate Zone II (Grades 3, 4
and 5) is some 30 m thick and consists of in situ, moderately to highly weathered bedrock materials
(mostly friable, gravelly silty sands and coreboulders) that indistinctly to distinctly preserve the
original bedrock minerals, textures and structures; the degree of preservation increasing with depth.
The bottom Zone III (Grade 2) consists of continuous bedrock with effects of weathering only along
and between structural discontinuity planes; the earth materials of zones I and II thus representing the
residual soil over bedrock. Constant volume samples show a general increase in porosity, silt and clay
fractions up the weathering profile, but a corresponding decrease in the sand and gravel fractions with
sub-zone IC having the highest density and lowest porosity. Soil-moisture retention curves, determined
with the pressure plate method, show increasing suctions from 0-4.19 pF (0 to -1,500 kPa) with
decreasing moisture contents of 35-18% for sub-zone IC samples, 32-7% for sub-zone IIB samples and
some 25-4% for sub-zone IID samples. Conclusion/Recommendations: These soil-moisture retention
variations reflect textural differences and point to the inherent role of suction in the unsaturated earth
materials. Differences in the volumes of calculated drainage and storage pores indicate that the earth
materials of sub-zone IC will have the lowest rates of infiltration and percolation, whilst those of subzone
IID will have the fastest rates and those from sub-zone IIB, intermediate rates.

http://www.thescipub.com/abstract/10.3844/ajgsp.2010.12.20 2011/03/13 - 07:40

Problem statement: Iran is an arid country and only small percent of its water demand is met by
rainfall. At present, about 55% of Iran’s water being supplied by aquifers and 45% from surface water.
Population growth, joint with economic development and rapid growth in industry and farming, has caused
a vast increase in demand for water in Iran. But the slow recharging aquifers have not been able to cope
with new condition. Approach: In this context, the importance of control and optimum utilization of
groundwater has been realized by Iranian and groundwater models because of their high effectiveness and
less expenses than other methods have been developed and us end by hydro geologists as a water source
management tool. Results: For this purpose, the quantitative model of the groundwater of Firozabad plain,
with area of 240 km2, which is located 100 km distant from the southwest of Shiraz, is prepared.
MODFLOW, GMS, groundwater modeling system, was used to build a groundwater flow model to
simulate the behavior of the flow system under different stresses for one year period (2006-2007) under
unsteady condition. First, a conceptual model was set up using simple GIS tools. Conclusion: The
numerical model was generated and, transient data from observation wells was used to calibrate the model.
Following this, the transient model was validated by using observation data for the period 2007-2008 .Then;
the completed MODFLOW model was ready for simulation runs. The results for the various scenarios
including predicting the status of water level in next 5 years, drilling new production wells and predicting
the status of groundwater under drought conditions was analyzed in Firozabad plain.

http://www.thescipub.com/abstract/10.3844/ajgsp.2010.21.26 2011/03/13 - 07:40

Problem statement: The Malaysian oil palm industry is an important industry to the nation. In 2009 alone the total export earnings reached RM 49.6 billion. The industry is under constant attack of its performance from the perspective of the environment, especially with regard to its Green House Gas (GHG) Emissions. Being an export orientated industry; this issue has to be tackled head on to quantify the GHG emissions of the oil palm industry. Approach: About 12 palm oil mills were selected for this gate to gate case study. Inventory data which consisted of raw material, energy usage and gaseous emissions were collected from the selected palm oil mills over a period of 3 years. A comparative study was conducted to compare the GHG emissions of the production of Crude Palm Oil (CPO) with and without allocation and biogas capture. GHG emissions from all sources are summed up and changed into units of CO2 equivalent (CO2 eq) which is used to standardize GHG emissions. Results: The main parameter causing the highest contribution to the GHG emissions within this system boundary is the biogas from the anaerobic treatment of the POME. When biogas is captured, the total GHG emission drops significantly. This shows the urgency and need for the palm oil mills to capture their biogas and use it as renewable energy. Conclusion: Less than 10% of the palm oil mills capture their biogas because the palm oil mills have excess energy from their biomass itself and to invest in a large sum of money to harvest the biogas will mean that they will need the infrastructure to use or sell the harvested biogas. Currently, the industry is moving towards either harnessing biogas from POME or producing value-added products such as fertilizer from POME which avoids methane generation. This move is visible with the gradual annual increase in the number of palm oil mills capturing their biogas.

http://www.thescipub.com/abstract/10.3844/ajgsp.2010.1.6 2011/01/11 - 03:42