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Showing 81 results for Ca

Mm Maghami, Nasrollah Iranpanah,
Volume 13, Issue 3 (11-2013)
Abstract

There are several methods for goodness of fit test for the skew normal distribution. This work focused on method of Meintanis [8] which is based on the empirical moment generating function. This test is discussed for the known and the unknown shape parameter. Meintanis [8] claimed that power of his test is higher than the Kolmogorov–Smirnov test. But this claim is true only for the known shape parameter. In this paper, we provide a new method for finding his test statistic that has more efficiency. Also Meintanis [8] not determine the size of himself test for the known shape parameter which in this paper we will determine it.
Nematollah Rashidnejad Omran, Maryam Nadri, Mehraj Aghazadeh,
Volume 13, Issue 4 (2-2014)
Abstract

The granitoid intrusion trending NW-SE, is expose in the East of Zanjan, structurally located in the Alborz - Azarbaijan zone and Tarom sub-zone. Petrographic composition of the intrusion includes a range of monzogranite, quartz-monzonite, quartz-monzodiorite to monzodiorite and in fact shows monzonite series composition. The major rock forming minerals consist of K-feldspar, plagioclase, pyroxene (augite-diopside) and quartz. They show granular, intergranular, microgranular to porphyrytic-microgranular textures. The intrusion has metaliminus high-K calc-alkaline to shoshonitic and I-type affinity. Enclaves of the intrusion have micro-granular mafic and monzodiorite, quartz monzodiorite composition, which are fine-grained than their host rock and have micro-granular porphyritic texture. According to the petrographical and geochemical studies, the magma has originated from partial melting of metasomitised sub-continental lithospheric mantle due to fluids and/or partial melts that originated from subduction edge. According to Harker Diagrams seems that monzodiorite magmas differentiation Leads to monzonite Formation And finally the Crystallization and differentiation are monzogranite. Therefore Crystallization and differentiation are the most important processes controlling rock types in the monzonite series intrusion. Tectonic diagrams indicate a continental margin magmatic arc and syn-to-post collisional intra-arc extensional environment.
H Amani,
Volume 14, Issue 1 (4-2014)
Abstract

The petroleum industry generates large amounts of solid and semisolid wastes known as oily sludges. Oily sludges can be generated in several steps of the petroleum production and refining in the bottom of tanks. The accumulation of oily residues in petroleum industry poses aserious environmental problem.The aim of this research was to evaluate an alternative process of removal of oily sludge from storage tanks that can be carried out by using biosurfactants. One of the most important properties of biosurfactants is reduction of surface tension and formation of oil/water emulsions. In this research, the ability of Pseudomonas aeruginosa PTCC 1570 to produce rhamnolipid was shown and the production of rhamnoilipd was confirmed by TLC and HPLC analysis. The rhamnolipid production started at exponential growth phase and continued during the stationary phase. During investigation of rhamnolipid production on sunflower oil as sole carbon, the results showed that the maximum rhamnolipid reached about 0.5 g/l. Finally, crude oil recovery from an oil storage tank using produced rhamnolipd was also demonstrated at CMC concentration. An oil recovery of up to 70 % was obtained in a storage tank using this method.
Nasrollah Iranpanah, Samaneh Noori Emamzadeh,
Volume 14, Issue 2 (7-2014)
Abstract

Traditional methods for testing equality of means are based on normality observations in each treatment, but parametric bootstrap methods offer a test statistic to estimate P-value by resampling. In article, first, Fisher, Cochran, Welch, James, Brown and Forsyth, Approximate F, Weerahandi, Adjust Welch and Parametric Bootstrap tests for testing hypothesis equality of means are defined. Then type one error and power of these tests were compared to each other by a simulation study for various sizes of samples and treatments. Finally sizes of these tests were calculated for the real data of Esfahan Cement factory.
Traditional methods for testing equality of means are based on normality observations in each treatment, but parametric bootstrap methods offer a test statistic to estimate P-value by resampling. In article, first, Fisher, Cochran, Welch, James, Brown and Forsyth, Approximate F, Weerahandi, Adjust Welch and Parametric Bootstrap tests for testing hypothesis equality of means are defined. Then type one error and power of these tests were compared to each other by a simulation study for various sizes of samples and treatments. Finally sizes of these tests were calculated for the real data of Esfahan Cement factory.
Mahmod Bahar, H Golnabi, Mahsima Hamidi,
Volume 14, Issue 3 (10-2014)
Abstract

The aim of this study was to estimate Specific Absorption Rate (SAR) induced in human head tissues, by assuming human head as a cubical model filled with lossy dielectric material and exposed to electromagnetic plane waves. The research is carried out by computational simulation using C programming codes. The numerical technique used in this study was Finite Difference in Time Domain (FDTD) method, along with Perfectly Matched Layer (PML) as an appropriate absorbing boundary condition. Different conditions including exposure conditions as well as physical parameters are employed, in order to compare the results to the past literature. Finally, the penetration depth of one of the specified models is expressed by means of interpolation. The results which are in complete agreement with the others in some cases, suggests that considering the biological tissues as dispersive media, would result in correct estimations whereas changing in the structure of the model, doesn’t differ if precise predictions are not important. Furthermore, the penetration depth correlation to frequency is in line with what is expressed in theoretical papers.
M Assadi, F. Ghahremaninejad, T. Nejadsattari, I. Mehregan, K. Poursakhi,
Volume 14, Issue 3 (10-2014)
Abstract

Genus Cerastium belongs to the subfamily Alsinoideae. This genus is represented with about 30 species in two subgenera (subgenus Dichodon and subgenus Cerastium) and three sections (sect. Strephodon, sect. Orthodon and sect. Schizodon) in flora Iranica area, of which 19 species were reported from Iran. The materials in the TARI herbarium were studied. The vegetative and reproductive characteristics of specimens were checked by stereomicroscope. In family Caryophyllaceae, the seeds bear numerous characters which can be used for taxonomic purposes. The ornamentation features of the seed surface and its relief are different from one species to another. The seeds were carefully taken from mature and dehiscent capsules. Pollen grains obtained from flowers bearing mature anthers. In this paper, Cerastium pentandrum (Caryophyllaceae) is reported as a new record from northwest Iran and Iranian plateau. It belongs to the subg. Cerastium sect. Orthodon. In this section teeth of the capsule are elongated, straight or reflexed, with flat or recurved margins. Morphological characteristics of the new record are provided. This taxon is compared with its closest relative C. balearicum. The ultrastructure of seed and pollen is examined by SEM.
Mostafa Rahimnejad, G Najafpor, Z Najafgholi,
Volume 14, Issue 4 (6-2015)
Abstract

Sediment microbial fuel cells (SMFCs) are new technology for production of clean energy. SMFCs able to convert a wide range of organic matter contained in the sediment to bioelectricity. In this study four different ecosystems (sea, hatchery, river and spring) was evaluated to assess their potential to generate electricity. Graphites were used as anode and cathode electrode. The lowest produced voltage was around 310 mV and produced from hatchery. Compare to other ecosystems river generate highest maximum generated power density of 37.09 mw/m2. The maximum generated voltage was 740 mV and it was completely stable for 12 days.
Fatemeh Talebi Khalilmahalleh, Reza Marandi,
Volume 14, Issue 4 (6-2015)
Abstract

 The environmental pollution of harmful toxic metals is one of the important issues in the world today. Nickel is one of the toxic heavy metals which if enters into the human body in high concentrations it will cause skin allergy, heart disease and various cancers. Therefore, there is need to remove Nickel from industrial wastewater. The purpose of this study was firstly to remove nickel from aqueous solutions with synthesized activated carbon from carrot remains and secondly to investigate the effect of variations of the adsorbent particle sizes on the equilibrium time and the removal efficiency. For this purpose, adsorption of Ni (II) ions on the adsorbent was studied in a batch process. Firstly, the activated carbon was prepared from carrot remains with particle sizes between 37 and 300 micrometers. The results showed that the maximum absorption efficiency occurs (100%) at pH of 6. Moreover, it was shown that with decreasing the adsorbent size from 300 to 37 µm, the equilibrium time will decreases from 130 to 20 min. Experimental data was best fitted onto pseudo-second order model. Langmuir and Freundlich isotherms equation were used to fit the adsorption isotherms. It is evident from this study that activated carbon is a suitable material for the uptake of Ni (II) from aqueous solutions.
  
Mina Ghiasi, B Noohi, M Zahedi,
Volume 14, Issue 4 (6-2015)
Abstract

The most prevalent and important mechanism of bacterial resistance to &beta-lactam antibiotics, is the production of &beta-lactamase enzymes which inactivate these drugs by the hydrolytic cleavage of the four-membered &beta-lactam ring during two steps which is including the nucleophilic attack of the bridging hydroxide ion on the substrate and eventual protonation of the leaving amine group. During this reaction, metal ions play an important role in the catalytic process. Despite the availability of &beta-lactamase crystallographic structures, their mechanism of action is still unclear and no clinically useful inhibitors of these enzymes have been reported. Density functional theory (DFT) using B3LYP and 6-31G, 6-31G* and 6-311G** basis sets have been employed to calculate the details of electronic structure and electronic energy of catalytic reaction of CcrA enzyme active center from metallo-&beta-lactamase enzymes (M&betaLs), penicillin from &beta-lactam antibiotics, and the formed complexes including ES, ETS1, EI1, EI2, ETS2 and EP respectively, has been used. Also all the thermodynamic functions including ∆Hº, ∆Sº and ∆Gº to form two transition states, ETS1 and ETS2, and for the total reaction are evaluated at 25 °C, 31 °C, 37 °C and 40 °C and 1 atmosphere pressure. In all calculations solvent effects have been considered by using PCM method for water, ethanol, protein environment, nitro methane and carbon tetrachloride. Finally this reaction proceeds during an exothermic and spontaneous process, and the first step, the nucleophilic attack of the bridging hydroxide ion on the substrate, is the rate-limiting step
Salman Ahmady-Asbchin, Naser Jafari,
Volume 15, Issue 1 (4-2015)
Abstract

Abstract
Methods of physical and chemical adsorption of heavy metals, has some disadvantages such as high cost and are ineffective at low concentrations. Methods for biological uptake of heavy metals in recent decades were considered. Among the biological adsorbent include: bacteria, fungi and alga, algae have the highest efficiency of metal uptake. This study determined that the main role in the uptake of metals, nickel (II) and cadmium (II) Alginic acid is responsible. Focus serratus brown alga, as adsorbent in this study used a cost-effective biological and biological uptake of cadmium and nickel ions simultaneously in a batch reactor has been studied. Surface structure of algae has been studied. Adsorption kinetics have been studied, the equilibrium time is about 300 minutes, the Langmuir adsorption isotherm using the equation can be interpreted as the maximum adsorption of about 0/85and 0/95mmol/g are, respectively, for cadmium(II) and nickel(II).
E Hoveazi, M Nabiuni, K Parivar, M Masomi, J Agh,
Volume 15, Issue 1 (4-2015)
Abstract

Today, induced pluripotent cells (iPS) have been recognized as a new and good cell source for cell therapy. In this study, we examined whether human iPS cells, cultured on scaffolds, can differentiate into definitive endodermal cells, as precursor for hepatocytes, pancreatic and lung cells. Embryoid bodies (EBs) composed of iPS cells then EBs were seeded on electrospinning nanofiber scaffold (PCL). The cells were differentiated into definitive endoderm by using IDE1(induced definitive endoderm). Expression of definitive endoderm markers including Sox17, FoxA2 and Gsc were confirmed by Immunocytochemistry attaining and RT-PCR analysis. In the present study, cells morphology and cells viability were evaluated by using a scanning electron microscopy and MTT assay respectively.The results of this study demonstrated the positive effect of 3D cultures, by using suitable factors, on definitive endoderm differentiation.definitive endoderm by using IDE1(induced definitive endoderm). Expression of definitive endoderm markers including Sox17, FoxA2 and Gsc were confirmed by Immunocytochemistry attaining and RT-PCR analysis. In the present study, cells morphology and cells viability were evaluated by using a scanning electron microscopy and MTT assay respectively.The results of this study demonstrated the positive effect of 3D cultures, by using suitable factors, on definitive endoderm differentiation.
G Rabani, R Ezati,
Volume 15, Issue 1 (4-2015)
Abstract

Acid rain, which is a wet form of gaseous air pollutants, is formed when air pollutants such as SO2, NO2, CO2 in atmosphere combine with water vapor of clouds. With the addition of concentration of these pollutants the amount of acid rain is increases. Acid rain that is the mixture of sulphuric acid, nitric acid and carbonic acid lead to change in the soil like the decrease in pH, nutrient liberation, the increase of releasing in toxic metals and the decline in fertility of soil that these cases results negative effects on plants. In present work wheat plants irrigated  and leaf spraied with  four treatments of acid rain which contain sulphuric acid and nitric acid with  pH= 2.5, 3.5, 4.5, 5.6 for a period of 32 days, whereas, control plants irrigated and leaf spraied by normal water at  pH= 7.4 . According to the results control plants in whole of growth and physiological indexes were better than treatments of  acid rain at pH= 2.5 and 3.5, also plants of acid rain treatment at pH= 4.5 and 5.6, were lower in other factors except photosynthetic rate, pigment content and carbohydrate content than control plants. Also acid rain at pH= 2.5 and 3.5 causes white spot in both surface of  leaf and tip and border atrophy.
Fatemeh Ghasemi, Reza Heidari, Rashid Jamei, Latifeh Poorakbar,
Volume 15, Issue 1 (4-2015)
Abstract

To assess nickel-induced toxicity in plants, Zea mays seeds after germination were cultured on hydroponic nutrient solution with nickel concentrations of 0, 50, 100 and 200 micro molar for a period of two weeks. Then its effect on the growth, Hill reaction and photosynthetic pigment's content were investigated. The fresh and dry weight of leaves and roots increased in 50 &muM nickel but decreased in 100 and 200 &muM. The decline in length of root and shoot were observed by increasing Ni concentration.According to results, root and shoot showed differential growth response to varried concentrations of nickel. Ni concentrations up to 100 &muM caused incrtease in the content of chlorophyll a, but it was decreased at 200 &muM Ni. No significant changes in chlorophyll b and carotinoids content observed. The rate of Hill reaction as an ability of chlorophyll a in the reaction center of PSII680 to split water, decreased by increasing Ni concentration.
Javad Mohammadi, Hasan Zaree Maivan, H Ejtehadi, ,
Volume 15, Issue 1 (4-2015)
Abstract

Vegetation of Kasf forest with an area of over 12 ha, located in the east-west direction at a distance of 20 kilometers north of the city of Bardaskan, between 57° and 52' and 30" to 58° and 00' and 00" East longitude and 35° and 22' and 30" to 35° and 30' and 00" North latitude, in a mountainous arid region with a minimum and maximum temperature of -10 and +45° C , respectively and average annual precipitation of 155 mm, at an altitude of about 1600 m above sea level with 15% slope was studied using floristic method 2 years after fire and life forms and geographical distribution of plant species were determined. Sixty nine plant species belonging to 29 families (25 Dicots, 3 monocots and one gymnosperm). The largest families were the mint (Lamiaceae) with 11, Compositeae (Asteraceae) with 9 and carnation family (Caryophyllaceae) with 5 species. The life forms included Therophytes with 36% (25 species), Hemicryptophytes 29% (20 species), Chamaephytes 16% (11 species), Phanerophytes 13% (9 species) and cryptophytes with 6% (4 species). The high percentage of Hemicryptophytes indicated dominance of cold mountainous climate and the presence of Asteraceae species such as harmala (Peganum harmala) showed sever disturbance had taken place in the region and thus, the need for administering greater ecological care and employing more extensive environmental supervision and management was identified.
Ebrahim Najdegerami,
Volume 15, Issue 2 (2-2015)
Abstract

Recently, concern over environmental and health effects of massive use of the antibiotics has let to growth of the bio-control agents application. Poly-&beta-hydroxybutyrate (PHB) is a natural polymer that can be depolymerized into water-soluble short-chain fatty acid monomers and acts as a microbial control agent. In this study, the effects of partially replacing the diet of Siberian sturgeon fingerlings with 2% and 5% PHB were investigated. Community level physiological profile (CLPP) was used to analyze anaerobic bacterial metabolic diversity in Siberian sturgeon fingerlings hindgut by using Biolog™ Ecoplate microplates. The results indicated that PHB increased metabolic activity in anaerobic bacteria in sturgeon hindgut. Also Lorenz curve and the Shannon index of Biolog™ Ecoplate data revealed that anaerobic metabolic potential of the bacterial community was different in the PHB-treated fishes as compared with the control situation.
, Soheila Parsa Pana,
Volume 15, Issue 2 (2-2015)
Abstract

The genus Pedicularis with 600-800 species is a semiparasitic plant distributed mostly in cold and mountainous regions of the northern hemisphere . In this study, nine species of this genus in the flora of Iran has been studied by electron microscopy . The surface of stigma of P. pycnantha and P. wilhelmsiana are flat. It is hemispherical in P. cabulica , P. caucasica , P. rechingeri, P. sibthorpii, P. condensate, P. strausii and conical only in P. rhinanthoides . In order to determine relationships between species, numerical analysis was carried out using 44 quantitative and qualitative of morphological, anatomical and palynological traits. The diagrams obtained from UPGMA and PCA methods were used to establish the relationship between the studied specie. Based on the results of the analysis, traits such as fruit pericarp thickness , spongy parenchyma thickness of leaf , stem height , stem thickness , total thickness of the stem and midrib length with high variability can be useful for species determination and evaluation of the similarities between them.
Fazel Iranmanesh, Mehran Maghsoudi, Ebrahim Moghimi, Mojtaba Yamani, Amir Hossin Charkhabi,
Volume 16, Issue 41 (5-2015)
Abstract

Deltas of the most important morphological units are a tremendous effect on agricultural activities, mining, coastal management and etc. Despite appropriate soil and water resources deltas, are influenced by environmental phenomena such as climate change and sea level changes. The effect of these changes will appear on physico-chemical, mineralogical deposits. This study was conducted to analyze the Karkheh delta depositional environments based on the chemical characteristics of ancient sediments. Depositional environments and locations of core were identified using digital data processing, geomorphology mapping and initial visit of the area. The coring was carried out with rotary drilling machine and continuously to a depth of ten meters in jofeir and Rofayeh. Among The cores, 20 samples were selected for mineralogical and chemical tests. Differences in chemical and mineralogical characteristics revealed at least three major discontinuities exist between sedimentary layers to a depth of 10 m. In addition, thickness and type of the sediment are not same conditions and it changes depending on the stability of depositional environments. Increasing of Mg / Ca, magnesium and salinity, and reducing of clay particles, show Sedimentary environments trend is toward dry conditions and high energy environments at depths from 10 to 5 meters. In contrast, the depth of 5 to 4 and 3 to 0 meter this trend towards more humid climate and low energy environments. Therefore, it is concluded that the depositional environment of the Karkheh River delta at the upper Holocene is not constant, and this has led to changes in the delta.
Akramosadat Mirlohi, Mahmoud Khalili, Seyed Mohsen Tabatabaei-Manesh, Hans-Joachim Massonne,
Volume 16, Issue 42 (5-2015)
Abstract

Garnet-micaschists from Haji Qara high, north of Golpayegan, are part of the metamorphic rocks of the Sanandaj-Sirjan Zone (SSZ). Lepidoporphyroblastic and porphyropoikiloblastic are the main textures and the mineral assemblages consist dominantly of Fe-biotite, muscovite and ferriphengite, metamorphic Fe-Mg chlorites (I-type and IIb), garnet and quartz. Staurolite, andalusite, plagioclase carbon, Fe-oxides and tourmaline are present as accessories. Petrographic evidences as well as mica chemistry along with other paragenesis and thermometric estimations indicate a path change from amphibolites facies to lower pressure and higher temperature gradient suggesting the presence of a local pluton which led to garnet porphyroblast, biotite and muscovite (overprinted in different orientation) and andalusite crystallization. The occurrence of chlorite, ferriphengite and Fe-oxides demonstrate a retrograde metamorphism during uplift and decompressional cooling path in the area.
Nasrollah Iranpanah, Parisa Mikelani,
Volume 17, Issue 40 (9-2015)
Abstract

One of the main goals in studying the time series is estimation of prediction interval based on an observed sample path of the process. In recent years, different semiparametric bootstrap methods have been proposed to find the prediction intervals without any assumption of error distribution. In semiparametric bootstrap methods, a linear process is approximated by a autoregressive process. Then the bootstrap samples are generated by resampling from the residuals.

In this paper, at first these sieve bootstrap methods are defined and then, in a simulation study sieve bootstrap prediction intervals are compared with a Standard Gaussian prediction interval. at last these methods are used to find the prediction intervals for weather data of Isfahan.
One of the main goals in studying the time series is estimation of prediction interval based on an observed sample path of the process. In recent years, different semiparametric bootstrap methods have been proposed to find the prediction intervals without any assumption of error distribution. In semiparametric bootstrap methods, a linear process is approximated by a autoregressive process. Then the bootstrap samples are generated by resampling from the residuals.

In this paper, at first these sieve bootstrap methods are defined and then, in a simulation study sieve bootstrap prediction intervals are compared with a Standard Gaussian prediction interval. at last these methods are used to find the prediction intervals for weather data of Isfahan.
, Ehsan Mir Mehrabi,
Volume 17, Issue 40 (9-2015)
Abstract

Fractional derivatives and integrals are new concepts of derivatives and integrals of arbitrary order. Partial differential equations whose derivatives can be of fractional order, are called fractional partial differential equations (FPDEs). Recently, these equations have been under special attentions due to their most practical usages. In this paper, we survey a rather general case of FPDE, to obtain a numerical scheme, the fractional derivatives in the equation are replaced by common definitions such as Grundwald-Letnikov, Riemann-Liouville and Caputo, to improve the numerical solution, partial derivatives inside the equation are discrete using non-standard finite difference scheme. Then, we survey the stability of numerical scheme and prove that the proposed method is unconditionally stable. Eventually, in order to approve the theoretical results, we use presented technique to solve wave equation with fractional-order that is very practical and widely used in physics and its branches. Numerical results confirm the findings of the theory and show that this technique is effective.

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