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A Comparative Study of Soil Carbon Sequestration between a Deteriorated Rangeland and Pinus eldarica and Fraxinus rotundifolia Stands
Get PDFTehran as the capital city of Iran is one of the most populous cities that overpopulation and industrial improvement there have caused the great diffusion of greenhouse gases. However, forestation in deteriorated rangelands of this city can have a high potential to decrease the density of atmospheric CO2. This research was done in two stands of Pinus eldarica and Fraxinus rotundifolia and the adjacent deteriorated rangeland as control (blank), in Chitgar forest park of Tehran and soil carbon sequestration content was measured. In addition, the relationship between soil organic carbon (SOC) and some physicochemical factors of soil was determined. Results indicated that Pinus eldarica and Fraxinus rotundifolia stands caused the increment of soil carbon sequestration around 46.18 and 37.2 tons per hectare, respectively in comparison with adjacent deteriorated rangeland. The content of SOC in two mentioned stands was more in the first layer than that of the second layer but it was opposite in blank (control). The result of stepwise regression showed that sand was the most important factor, affecting SOC. According to the results of correlation analysis, there was a positive significant relationship between SOC and % silt and % sand and a negative significant relation between SOC and %clay and %gravel. The economic values of carbon sequestration increment in mentioned stands were calculated to be 13.9 and 2.5 million dollars, respectively. Our study showed that forestation is an effective land-use option to restore deteriorated lands of this area and have a high potential to alleviate global warming and climate change
Shear Strength of a Crushed Sandstone-Mudstone Particle Mixture
Get PDFThe present study focuses on the shear strength of a crushed sandstone-mudstone particle mixture. The mixture is widely used as a main filling material in many geotechnical engineering works. In order to investigate the shear strength of the mixture, triaxial tests under different confining pressures in laboratory are performed for 108 specimens with different dry densities and water contents. The dry density of the specimens ranges from 1.80 to 2.10 g/cm3, and the water content from 4.00 to 9.00 % and to saturation. In the tests, four confining pressures, which are 100, 200, 300 and 400 kPa, are applied. The testing results indicate that the angle of shearing resistance of the mixture in unsaturated state ranges from 16.90 to 32.98°. The angle of shearing resistance is generally decreasing with the increase of the confining pressure. With the increase of the dry density, the angle of shearing resistance increases. The angle is generally increasing then decreases as a parabola with the increase of the water content. The wetting may decrease the value of the angle about 0.4 to 2.7°
Improved Determination of Apparent and Plastic Viscosity for Aqueous Solution of Drilling Fluid Additives
Get PDFRheological behavior of drilling fluids is very complex. Exact determination of shear rates helps to predict apparent and plastic viscosity very accurately, which will help to monitor drilling operation efficiently. This paper deals with the improved estimation of shear rates of drilling fluids with varying rotor rotation using coaxial-cylinder Fann viscometer, which is based on generalized difference equation under purely steady, laminar and isothermal tangential fluid flow condition. Rotor rotating speeds and bob dial readings are the input variables for shear rate prediction. The proposed equation was used to calculate shear rates accurately (hence apparent, plastic viscosity and yield point) for several non-Newtonian fluids, mainly, aqueous suspension of bentonite, xanthan gum, poly anionic cellulose and carbomethoxy cellulose solution. Finally, the predicted consistency plots were compared with those which are obtained from the conventional method of estimating the rate of shear for drilling fluids
Editorial: Journal of Advanced Thermal Science Research
Get PDFJournal of Advanced Thermal Science Research (JATSR) is a peer-refereed online journal that publishes high-quality articles in the field of thermal science. The aim of this journal is to provide a platform for scientists and engineers all over the world to discuss various new developments in different areas of thermal science. This journal is published twice a year by Avanti Publishers. The journal will publish original articles, review articles, technical notes, and short communications, related to the field of thermal science.
On the behalf of the editorial board members of the Journal of Advanced Thermal Science Research, it is my pleasure to welcome you to the first issue of this the journal. This inaugural issue of the JATSR, Vol. 1, Issue 1, includes four peer-refereed original articles, from authors representing four countries: Spain, Romania, India, and Turkey. On behalf of editorial board members, and myself I wish to express my sincere gratitude to the authors of the articles for their willingness to disseminate their research achievements through this journal.
The first paper of this issue is A Parametric Study of Heat Transfer for the Optimization of Fin Sinks by Blanco et al. In this study, the authors developed a design tool called “Opti-fin” for a Matlab ® environment that allows the user to configure a fin on the basis of the material and the thermal heat that will be released. Their study also includes a realistic estimation of fluid (air) flows that control the temperature dependency of the fin. This tool has been validated by computational fluid dynamic simulations using ANSYS-FLUENT®, in which the results of the simulation and the actual triangular shaped fin showed a remarkable similarity.
The second article is Contact Photothermal Techniques for Thermal Characterization of Liquids by Dadarlat. Two contact photothermal techniques, the well-known photopyroelectric calorimetry, and a recently introduced photothermoelectric, are proposed for thermal inspection of some liquid samples. The paper contains a summary of the recent results and a comparison of the investigations performed with the previously mentioned techniques for the measurement of the dynamic thermal parameters (thermal diffusivity and effusivity) of some liquids of interest: magnetic nanofluids with transformer oil as carrier liquid and various concentrations of magnetite (Fe3O4) nanoparticles. For both techniques, the same detection configurations have been used: (i) the front detection configuration, together with the thermal-wave resonator cavity (TWRC) method as scanning procedure, was used to measure the value of thermal effusivity; (ii) the back configuration, together with the same TWRC technique, leads to the direct measurement of thermal diffusivity. The main theoretical aspects of the particular detection cases for both techniques are described and the performances (advantages and limitations) of the methods are analyzed.
The third manuscript is Cold Flow Simulation in Underground Coal Gasification (UCG) Cavities by Chatterjee et al. A comprehensive three-dimensional numerical study is conducted to understand the hydrodynamics within a given cavity size which would give a relatively quick but reliable insights into the process. Five different cavity sizes are considered inside which the complete turbulent transport is simulated. Apart from the usual vertical and horizontal injection, the effect of inclined injection on the hydrodynamics is also reported here for the first time.
The fourth and last paper of this issue is Structural Evolution Properties of Cu-25 wt %Sn Alloy During Ball Milling by Arslan. In this study, Cu-25 wt %Sn alloy samples were prepared by the mechanical alloying process using planetary high-energy ball mill. The alloy formation and different physical properties associated with their formations were investigated as a function of milling times of 0, 10, 20, 70, 80, 100, 120, 150 and 200 h by means of the x-ray diffraction (XRD) technique, scanning electron microscopy (SEM) and differential scanning calorimeter (DSC).
Finally, on behalf of editorial board members, I would like to express our special thanks to the referees, who have committed their valuable time and effort to refereeing the articles included in this issue.
Hosni I. Abu-Mulaweh
Co-Editor-in-Chief
Journal of Advanced Thermal Science Research
Indiana University-Purdue University Fort Wayne 2101 E. Coliseum Blvd. Fort Wayne, IN 46805 USA
E-mail: [email protected]
 
Quantum Game Techniques Applied to Wireless Networks Communications
Get PDFIn order to analyze the power control problem, the wireless quantum network nodes are modeled as players at a quantum game. The power control problem is one of the most significant wireless communications challenges which characteristics make it proper to be modeled by means of game theory techniques. The problem results in non-cooperative game by nature, but, under quantum rules, a larger strategy space leads the players to choose a coalition strategy as the best option. Thus, the use of quantum game strategies makes possible the emergence of new equilibrium, which guarantees the best possible performance to the whole network. We show also that the whole network power consumption decreases when the intrinsic parallel behavior of quantum computation is capitalized. Moreover, the design of efficient medium access control algorithms is possible
Uni-Type Modal Operators On Intuitionistic Fuzzy Sets
Get PDFIntuitionistic Fuzzy Modal Operator was defined by Atanassov, he introduced the generalization of these modal operators. After this study, some authors defined some modal operators which are called one type and two type modal operator on intuitionistic fuzzy sets. In these studies, some extensions and characteristic properties were obtained.In this paper we defined new operators and examine some properties of them. In view of conclusions, it is shown that these operators are both one type and two type modal operators on Intuitionistic Fuzzy Sets. So, these common type modal operators are called uni-type modal operators on Intuitionistic Fuzzy Sets
Diagnosis and Prognosis of the Hearing Impairment Risk
Get PDFThis paper describes a methodological approach on the analysis and on the statistical and probabilistic assessment of the hearing impairment risk, based on the hazards quantified as risk predictors, in order to establish the modalities for assessing the caution limits related to the acceptability ranges. The research has been achieved within the PN 45 07 01 15 project in the framework of the NUCLEU/2009-2010 program.The statistical approach is based on the rational quantification of what exists and can be observed, the probabilistic part of this fact representing the extrapolation to what it can be reasonably deduced from these statistics of hearing impairment occurrence probability. This project has a national and international interest, entailing the increase of occupational health and safety level and ensuring sustainable environmental quality and comfort at workplaces
On Jump-Critical Ordered Sets with Jump Number Four
Get PDFFor an ordered set P and for a linear extension L of P, let s(P,L) stand for the number of ordered pairs (x, y) of elements of P such that y is an immediate successor of x in L but y is not even above x in P. Put s(P) = min {s(P, L): Llinear extension of P}, the jump number of P. Call an ordered set P jump-critical if s(P - {x}) < s(P) for any x ϵ P. We introduce some theorems about the jump-critical ordered sets with jump number four
Vis-NIR Spectroscopy for Determining Physical and Chemical Soil Properties: An Application to an Area of Southern Italy
Get PDFThe development of rapid, accurate, cost effective methods to determine soil physical and chemical properties is important for sustainable land management. In the last two to three decades, the interest in using visible and near infrared (Vis-NIR) spectroscopy as an alternative method for determining soil properties has increased. To obtain reliable predictions of soil properties, multivariate calibration techniques such as Partial Least Squares Regression (PLSR) are commonly used to correlate the spectra with the chemical, physical and mineralogical properties of soils.The objective of the paper was to assess the potential of Vis-NIR spectroscopy coupled with PLSR to determine soil chemical and physical properties such as organic carbon (SOC), sand, silt, clay, and calcium carbonate (CaCO3) contents in a sample site of southern Italy.Spectral curves showed that the soils could be spectrally separable on the basis of chemical and physical properties. PLSR calibration models were derived for each of the soil properties and were validated with an independent data set. The optimum number of factors to be retained in the calibration models was determined by leave-one-out cross-validation. The accuracy of the calibration and validation models for the different soil properties was evaluated with the coefficient of determination (R2) and the root mean squared error (RMSE). The results showed that predictions were satisfactory for all soil properties analyzed with high values of R2 > 80.A combination of Vis-NIR spectroscopy and multivariate statistical techniques, therefore, can be used as a rapid, low cost and quantitative means of characterizing the soils of southern Italy