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Showing 51 results for Type of Study: Research Paper

Nasrollah Iranpanah, Morteza Mokhtari Moghadam,
Volume 10, Issue 1 (3-2010)
Abstract

Shewhart control charts are widely accepted as standard tools monitoring manufacturing statistical processes. The control charts have not applied, when the process distribution is not normal. The bootstrap is one of the resampling methods that can be used in statistical quality control without normality assumption. In most of papers, only the percentile bootstrap confidence interval is used for control limits. In this paper, we apply percentile bootstrap, bootstrap-t, bias corrected accelerated (BCa) and approximate bootstrap confidence interval (ABC) for mean control limits of statistical process. Then, the bootstrap confidence intervals are used and compared for mean control limits in simulation study. Finally, the bootstrap control limits are used for mean of CO2 data in Isfahan Zamzam factory.
, , ,
Volume 10, Issue 3 (2-2010)
Abstract

Abstract
In lizards spermatogenesis takes place in two different ways: seasonal and non-seasonal. In seasonal type usually found in temperate-climate lizards, the process of spermatogenesis is limited to a defined period of the year, whereas in non-seasonal type observed in tropical-climate lizards this process occurs continuously year-round. In this research the spermatogenesis activity was studied in species of Laudakia caucasia occur in central Zagros Mountains. To fulfill this task, we collected 34 specimens of this species from Norabad, Lorestan province, during two seasons of their biological activity. The specimens were then killed and their testes were removed. After measuring the testis dimensions the specimens were prepared for histological observations. The results obtained from morphometric, histometric as well as histological examinations showed that the spermatogenesis in this taxon is seasonal and contains two phases: active and inactive. The active phase which coincides with late spring to early summer is the period in which cells in seminiferous tubules are actively involved in sperm-making process and all shapes of spermatogenic cells are seen within the tubules. During the inactive phase which begins in late-summer and lasts until the next spring, no spermatozoids is seen in the tubules as the process of spermatogenesis has been ceased. However, in this period, the regeneration activity is taking place in the gonad and the animal is preparing for its next spermatogenesis season.
Maedeh Rezaei, Ramzanali Khavari-Nejad, Farzaneh Najafi,
Volume 10, Issue 4 (2-2011)
Abstract

The effects of cadmium and iron interaction on some physiological parameters in rice (Oryza sativa L.cv.fajr) plant were studied. The four days old seedlings were transferred to pots containing sand, irrigated with Hoagland solution in growth chamber. The 15 days old plants were treated with 0, 50 and 100 &muM  CdCl2 supplemented with 5, 10 and 20 ppm Fe as Fe-EDTA. Plants were grown under controlled condition and harvested after 30 days for measurements of some biochemical and physiological parameters. Treatments were conducted with four replications. Under Cd stress, growth of plant decreased. In plants treated with CdCl2, relative growth rate, net assimilation rate and photosynthetic rate were decreased. Addition of Fe-EDTA (10 and 20 ppm) moderated cadmium effects. Under Cd stress without Fe, respiration rate and CO2  compenstation point increased, however, in solutions containing both CdCl2 and Fe-EDTA, respirations rate and CO2  compenstation point decreased. In plants treated with CdCl2, catalase activity increased. However, after increasing Fe in solution containing CdCl2, catalase activity decreased. Therefor, the results indicated that in CdCl2 treated plants with increasing Fe-EDTA, the toxic effects of Cd decreased.
Shana Vosoughrazavi, H Ejtehadi, H Zaree, S Tavakoli,
Volume 10, Issue 4 (2-2011)
Abstract

Aquatic ecosystems are the main biotic ecosystems that contain variety of plant species and their destruction result in the reduction of plant species diversity. In the present investigation, species diversity of aquatic plants in permanent, seasonal, forest wetlands and ricelands of the west and east of Mazandaran province was determined. First, 30 habitats were determined on the map and the total 161 samples, based on systematic-random sampling, were established. 126 species of aquatic plant of the habitats were collected and the cover of each species ,based on the area of quadrate that accupied by plants, was recorded. The results showed that species diversity of aquatic plants in the west and east is governed by the moisture gradient. Based on De Martonne classification system of climate, the west and east of Mazandaran province have wet and mediterranean climate, respectively. Therefore, the condition for the growth of aquatic plants in the west is more appropriate than in the east. Species diversity of wetlands and ricelands in the west was higher than that in the east. In this study, classification system of den Hartog & Veld for aquatic plants that classify them as hygrophytes, real aquatic and wetland species was applied and diversity indices for all three categories were calculated. The results revealed that diversity of hygrophytes is the highest among them and the real aquatic plants have higher species diversity than wetlands. T-test, based on Shannon index, showed significant differences between diversity of the west and east as well as between three group of macrophytes (P<0.05).
,
Volume 11, Issue 1 (10-2011)
Abstract

In the present study morphological, anatomical, polynological and molecular biology features of the genus Utricularia L. belonging to Lentibulariceae family of Lamiales were studied. This genus contains two species, namely: U. minor L. and U. australis R. Br. The morphological characters of the two species such as the stolone length, presence or absence of rhizoids and bags shape (bladder) of the trapper are different. In anatomical studies, the epidermal stem cell shape, thickness and shape of aeranchymous cells and cortex are useful for separation of these two species from each other. In palynological studies, it was revealed that pollen of studied taxa are multi-aperature and without pore and ornamentation of exine surfce is also grooved. Results from chloroplasty analysis of trnL-F sequences indicate that U. australis and U. minor are related with U. macrorhiza and U. intermedia. respectively.
Saeed Afsharzadeh, Shabnam Abbasi,
Volume 11, Issue 1 (10-2011)
Abstract

Abstract
Introduction of plant groups of Yahya Abad region and their relationship with environmental factors
The region of Yahya Abad is located at Southern slops of Karkas mountains with about 6000 hectare area, at 35 kilometer-SW of Natanz in Isfahan, is one of arid mountain ecosystems in Iran. The aim of the study is grouping the plant species and their relationship with various environmental factors such as elevation and soil characteristics. sampling carried out in systematic-random method with 1.5×2m quadrates and percentage of plants cover estimated. In this research different methods of Cluster Analysis and Ordination were performed in order to study of plant groups and their relationship with environmental factors. Cluster Analysis demonstrated eight plant groups and Different methods of ordination indicated the altitude factor as the main factor in the separation of plant groups. Due to relatively uniform topography and livestock's grazing in this region there wasn’t clear relationship between altitude and diversity indeces.
Keywords: Vegetation, Environmental factors, Cluster Analysis, Ordination, Diversity indeces
, , Seyed Lotfollah Sharifi,
Volume 11, Issue 3 (2-2011)
Abstract

In this paper nanoparticles of lithium-cobalt oxide on alumina and silica substrates, by sol-gel method and with citric acid as gelling agent were prepared. The effects of different substrates on size, shape and catalytic effects of nanoparticles were studied. To evaluate the catalytic activity, rate of decomposition of hydrogen peroxide in the presence of any of the samples by measuring the volume of oxygen gas released at the time, was investigated. The X-ray diffraction patterns (XRD), scanning electron microscopy (SEM) and FT-IR spectra confirmed the formation of Co3O4 and LiCoO2 phases
Salman Rahmani,
Volume 11, Issue 3 (2-2011)
Abstract

An efficient, mild and environmentally- friendly approach was developed for the synthesis of bis arylidine cycloalkanones. SnCl4 was found as efficient catalyst for cross aldol condensation of cycloalkanones and aromatic aldehyde for synthesis of &alpha,&alpha'-bis(substituted-benzylidine) cycloalkanones in ethanol as a green solvent. In this method, the reaction works easily for a variety of aldehydes with both electron-donating and electron-with-drawing groups to give corresponding &alpha,&alpha’-bis(substituted-benzylidene) cyclohexanones in good to excellent yields. Comparing the known methods, the main advantages of our method are short time, user-friendly, low cost procedure, clean and environmentally benign reagents with ease of separation of the product and mild reaction condition with good to excellent yield for products
Vahide Keramati,
Volume 11, Issue 3 (2-2011)
Abstract

A simple hydrothermal method was designed for the synthesis of the nanostructure Barium phosphonate in presence of cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) as surfactant. FT-IR, EDAX, XRF, XRD, SEM were used to characterize this material. Effect of solvent on morphology complex was discussed. Thermogr avimetric analysis (TGA) shows the existence of porosity and stability of the material.  
Jamil Vaezi, Fatemeh Batyari, Hamid Ejtehadi, Mohammad Farsi, Mohammad Reza Joharchi,
Volume 11, Issue 4 (2-2012)
Abstract

The genus Salvia is morphlogically investigated to provide an identification key based on morphological characters in the Northeast of Iran. In this study, we examined more than 350 herbarium and collected specimens of different populations and measured 79 quantitative and qualitative (vegetative and generative) characters. The results of the multivariate analysis (principal component analysis) and Nonparametric Test (K independent samples) indicate that the morphological characters such as blossom shape, ring of trichome inside of corolla and protrusion style differentiated the Salvia species. For the first time, the species Salvia shariffi is reported in the Jonoubi and Shomali Khorassans.
Nasrollah Iranpanah, H Tavasoli,
Volume 12, Issue 1 (11-2012)
Abstract

Mortality forecasts are nowadays widely used to create and modify retirement pension schemes, disability insurance systems and other social security programmers. Experience shows that static life tables overestimate death probabilities. The reason for this overestimation is that static life tables, through being computed for a specific period of time, cannot take into account the decreasing mortality trend over time. Dynamic life tables overcome this problem by incorporating the influence of the calendar when graduating mortality.
In this paper, we first apply the Lee-Carter model for estimation of mortality rate. Then, we use parametric and semi parametric bootstrap prediction intervals for mortality trend. Finally, these methods are applied for analysis of mortality data of Iran.
Sahand Tadbiri, Mahmoud Almasian, Mohsen Pourkermani,
Volume 12, Issue 2 (11-2012)
Abstract

Introduction and purpose : Chah-Savar-Agha quarry, the quarry which belongs to Neyriz marble quarries complex, is one of the important economical center in the Fars province. In recent years, some slumps and instabilities have occurred in this area and this phenomenon increases the importance of structural studies and investigation of tectonic stress specially insitu stresses. Therefore, the main purpose of this research is the investigation the role of tectonic structures such as joints, fractures, insitu stress phases and effects of them on instabilities of the northern slope.
Method :
By field studies and measurement the geometrical characteristics of the fractures, including dip and dip direction of joints, fillings and the number generations of filling, they are analysed by DIPS5.1 software to achieve the structural analysis and reach to the insitu stress phases.
Results :
According to the results, at least two insitu stress phases are acceptable in the area.
- Releasing stress phase : this stress phase with the South West- North East trend has caused the reactivation of some old joints and creation of some young fractures in the area. The releasing stress phase has been created by rapid extraction from the quarry.
- Local tensional phase :
Field observations have indicated that the Northern slope was creeping in the North East direction and this phenomenon has created the tensional stress phase with the East- West trend in the area and this stress phase has created some vertical fractures with the North-South trend also.
The creep mechanism in the Northern slope has been created by burden of debris which have been accumulated on the top of Northern slope.
Burden of these debris has created the vertical stress that has caused the creep mechanism upon a fracture with N152/50NE identity in the South East Strike.
B. Shafiei, J Shahabpour,
Volume 12, Issue 2 (11-2012)
Abstract

Productive and non-productive intrusive of Oligocene-Miocene age with similar mineralogical composition in Kerman porphyry copper belt exhibited important geochemical differences in terms of trace and rare earth element geochemistry. The productive intrusives are best characterized by low contents of MnO (&le0.1 wt.%), Y(&le18ppm), &SigmaHFSE (&le۱۰۰ppm), heavy rare earth elements (Yb&le1.9 ppm), high Sr content(&ge406-1015ppm), high (Sr/Y&ge30), significant REE fractionation (La/Yb&ge20), as well as positive Eu anomalies(Eu/Eu&ge1), when compared with non-productive intrusives(MnO&ge0.1wt.%,Sr=184-576ppm,Y=12-50ppm, Sr/Y<30, La/Yb<15,Eu/Eu*<1).These signatures are indicative of hydrous and oxidized magmas that formed in a condition which has been different from that of the non-productive intrusives. Based on the present study, the discrimination diagrams which can be used as a tool for identification of productive intrusives, where they are accompanied by nonproductive intrusives, in other copper provinces in Iran, are as follows: MnO-Y, &SigmaHFSE-Y, Sr/Y-Y, Sr/Y-SiO2 , La/Yb-SiO2, La/Yb-Yb, Eu/Eu*-SiO2.
S. A. Alavi, M. R. Ghasemi, M. Mokhtari, A. R. Gelalzadeh, Reza Alipoor,
Volume 12, Issue 2 (11-2012)
Abstract

The Pazanan oil field is located in Dezful embayment, 150 km south east of Ahvaz and south east of Aghajari oil field. Aghajari formation has formed surface outcrop and also the Asmari formation with 7 reservoir layers is the main reservoir rock in this oil field. In this research high fractured areas in the Pazanan oil field have been analyzed based on subsurface date and utilization of subsurface analyzes method. It seem to be the Pazanan oil anticline is an asymmetric fold with high dip in south west limb and the middle parts have been distinguished as areas with potential of fractures development with respect to longitudinal Curvature. Geometrics analysis of this structure indicate that south west limb in more parts and north east limb in middle parts have been distinguished as areas with high fractures density. Axial bending (longitudinal) of the Pazanan anticline is because of growth and propagation and combining of separate anticlines shear zone result of strike slip faults motion and old strike slip structures.
Mansour Mohammadian, Behroz Goleen, Z Khosravi Lorgani,
Volume 12, Issue 3 (11-2012)
Abstract

Citrus fruits are tropical and sub-tropical crops. The main problem in sub-tropical area is chilling and frost damage. Regarding the sensitivity of citrus fruit to low temperature and the conjunction of the fruit harvest season with low temperature, the investigation of the physiological impacts of low temperature treatments are very important. In this study, flavedo tissue of five cultivars of citrus fruit was examined to compare some enzymatic antioxidants activities including Superoxide dismutase (SOD), Ascorbate peroxidase (APX), peroxidase (POD) and Catalase (CAT) under various cold treatments, i.e. control (~15), 3, 0, -3 and -6 °C in two stages of before and after ripening of the fruits. The high activity of SOD enzyme in the flavedo tissue of the examined cultivars indicated that this tissue is the first defensive line of the fruits facing low temperatures treatments. The activity of CAT enzyme in the flavedo tissue of Sanguinello before and after ripening stages was higher in all low temperature treatments compared with other cultivars. Unshiu and Local Orange had maximum and minimum activity of APX enzyme, respectively in both stages. Also, Unshiu, Sanguinello and Local lemon showed increasing activity of POD enzyme by decreasing temperature
Farzaneh Zandi, Ramin Hossini, Neda Soltani, , ,
Volume 12, Issue 3 (11-2012)
Abstract

Oil pollutions as a consequence of increasing consumption of petroleum, have a tremendous effect on water and soil ecosystems and their microflora. In this study the diversity in physiological parameters, including growth rate, photosynthesis, chlorophyll-a and phycobiliproteins content, between cyanobacterial strains flora isolated from oil-polluted and non-polluted areas, were assessed. To this end, strains were isolated and purified. The experiments were carried out on logarithmic phase cultures of the isolates in suitable liquid media. The chlorophyll and phycobiliproteins contents were determined using a colorimetric method. Photosynthesis was measured by Oxyview apparatus. Growth rates were calculated based on dry weights. Under laboratory conditions, the photosynthesis activity and the chlorophyll content of isolates from oil-polluted sites were significantly lower than non-polluted isolates. On the other hand, the growth rate average of strains from oil-polluted sites was significantly higher than non-polluted strains. Also despite the higher phycobiliproteins content in non-polluted isolates, there was no significant difference in any of these pigments between the two groups. Altogether the results showed that in response to petroleum stress, the cyanobacteria restore the decrease in their chlorophyll content and photosynthesis activity by increasing their biomass. In fact the response is the reflects of restructuring cyanobacterial flora from sensitive autotrophic species to oil-pollution resistant mixotrophic species in the polluted ecosystems that in addition to photosynthesis are able to use crude oil as an energy source for their growth requirements, hence overcome the energy loss due to reduction of photosynthesis and even increase growth rate than non-oil-pollution isolates.
Farhad E.ghodsi, , ,
Volume 12, Issue 4 (11-2013)
Abstract

MgO thin films were prepared using sol-gel method. The influence of annealing temperature on optical, structural properties and surface morphology of the films were investigated using FTIR, UV-Visible and photoluminescence (PL) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical constants and thickness of the films were determined by pointwise unconstrained minimization approach. The optical transmittance has decreased with increase of annealing temperature. The refractive index and extinction coefficient of the films increased while the thickness and optical band gap of the films decreased with increasing of annealing temperature. The thickness of film decreased from 635 to 420nm and optical band gap decreased from 4.05 to 4.02eV. The photoluminescence (PL) intensity increased with annealing temperature. XRD patterns demonstrated that the prepared films at 500℃ were amorphous. In addition, the crystal structure of MgO nanopowders which was prepared by sol-gel method was investigated. The crystalline orientation of MgO nanopowders was improved by increasing the sintering temperature. The SEM micrographs show that a homogenous and crack-free film can be prepared at 500°C.
 
, Atefeh Jafari, Komail Boustani, Mojtaba Salouti,
Volume 12, Issue 4 (11-2013)
Abstract

In this study, Fe3O4/SiO2 core-shell magnetic nanoparticles (NPs) by two-step process were synthesized. First, Fe3O4 NPs by co-precipitation method of iron ions (Fe3+ and Fe2+) in an alkaline medium without using surfactant were synthesized and then silica shell with a non-thermal method without the use of linkers were installed on Fe3O4 NPs. facility of this method is noticeable. Results of X-ray powder diffraction patterns show that the inverse spinel structure of Fe3O4 and amorphous silicon was made. Fourier transform infrared spectroscopy confirmed the formation of these structures. There is no additional peak in XRD pattern which indicates that the prepared particles have pure Fe3O4 phase. TEM images show that core-shell structure is formed and mean size of NPs is 20 nm. VSM analysis showed that saturation magnetization of Fe3O4 nanoparticles after coating with silicon decreased.
Saeed Irian, A. Darash,
Volume 13, Issue 1 (5-2013)
Abstract

Species of the genus Citrus grow in different parts of Fars province. The present study aimed at investigating the ontogeny of Citrus grandis pollen grains and petal secretory sacs. Flowers and blossoms were collected from the gardens located in Jahrome during the flowering period, fixed in FAA and stored in 70% ethanol. Samples were prepared and embedded in paraffin and sectioned using a rotary microtome. To examine petal secretory sacs, petals were placed in a glycerine-alcohol mixture, and sections were prepared for light microscopy using a sterilized razor blade. Results showed anthers with four pollen sacs. Cytokinesis appeared simultaneous, and the microspore tetrads were of a tetrahedral type. Pollen grains at a time of dispersal have two cells, containing four vegetative openings with reticulo-faveolate decorations. In the initial petals, three tissues were detected with tightly packed dividing cells. Throughout petal developmental stages, the rate of epidermal cell division was reduced, while parenchymal tissue differentiation was limited to an increase in cell dimensions, cell wall thickening and the intercellular space. In addition, the number and size of the vascular bundles increased during growth. The formation of petal secretory sacs is limited to the first stage of its development, while later in the development, this structure only increased in dimensions.  In conclusion, based on our histological examinations, Citrus grandispetal secretory sacs change in a five stage process
Latifeh Pourakbar, ,
Volume 13, Issue 1 (5-2013)
Abstract

Copper and nickel are an essential micronutrient for plants, playing an important role in maintaining plants' natural metabolism and growth, but in excess both heavy metal are also a proven inhibitor of various physiological functions. In this study maize (Zea mays L.) plants grown in hydroponic culture were treated with CuSO4 (0, and 100 &mum),NiSO4 (0,100 and 200&mum)and interaction of CuSO4 (100 &mum)and  NiSO4 (100 and 200 &mum). After 1 mounth of treatment, growth parameters and some biochemical changes were studied in roots and shoots of plants. The results showed that with increasing Cu and Ni concentration, pigment contents (chlorophyll a, b and total carotenoids), root and shoot length and dry weight were decreased, while k+ leakage, malondealdyde as indicator lipid of peroxidation and some antioxidant enzyme activity were increased. Also result showed that interaction of Cu and Ni has been cooperation effects on together and intensify each other's work

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