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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Rangeland Science
- نوع مقاله: Journal Article
- کلمات کلیدی: PCA,Thymus kotschyanus,Taleghan rangelands,TWINSPAN
- چکیده:
- چکیده انگلیسی: Growth and productivity of plants are mainly affected by various environmental
factors in different ecosystems and natural habitat in the world. This research aims to study
the existing relationships between the phytosociology characteristics of Thymus
kotschyanus and environmental factors in order to find the most important factors
governing development of the species in middle Taleghan rangelands, Iran. Subsequent to
indicating the study region, the required flora and environmental data were collected by
field survey. Plot size and sample size were determined by minimum area and vegetation
procedure methods, using 40 plots along four 100 m transects. The characteristics
including floristic list, percentage of canopy cover, number of plants as well as height, the
largest and smallest diameter, and freshness of T. kotschyanus were recorded. Likewise,
bare soil percentage, litter percentage, and stone and gravel percentage of topsoil were
recorded in each plot. Moreover, in order to study the soil features, eight soil profiles were
taken in each site up to 30 cm depth at the beginning and end of each transect.
Classification of vegetation cover was performed by TWINSPAN analysis while factors
influencing the change in vegetation characteristics of T. kotschyanus were determined by
PCA analysis. Results demonstrated that factors involving slope, altitude, organic matter,
lime content, nitrogen content and soil texture show the highest impact on vegetation
characteristics. Overall, variables including elevation ranging between 2300-2500 m, slope
in the range of 20% - 40%, and fertile sandy loam textured soils in presence of nitrogen
and high organic matter content as well as low lime content provide the most suitable
condition to develop a high production T. kotschyanus.- انتشار مقاله: 06-08-1392
- نویسندگان: Leila Darvishi,Mohammad Ali Zare Chahouki,Mohammad Jafari,Hussein Azarnivand,Majid Yousefi Valikchali
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Rangeland Science
- نوع مقاله: Journal Article
- کلمات کلیدی: LR,MDA,Actual vegetation map,Geo-statistical method,ENFA,Kappa coefficient
- چکیده:
- چکیده انگلیسی: Eurotia ceratoides (L.) C. A. Mey is an important plant species in semi-arid lands
in Iran. New approaches are required to determine the distribution of this plant species. For
this reason, geographical distributions of Eurotia ceratoides were assessed using three
different models including: Multiple Discriminant Analysis (MDA), Ecological Niche Factor
Analysis (ENFA) and Logistic Regression (LR). The study area was located in northeast
rangelands of Semnan, Iran. Sampling was performed in each vegetation type using
randomized-systematic method. Vegetation data in addition to environmental factors' data
such as topography and soil were prepared. The MDA and LR methods were performed with
SPSS software as predictive modelling methods based on presence and absence data. The
ENFA model was performed by the means of necessary statistical analysis in Biomapper
(Version 4.0) software only by presence data. The plant predictive mapping needs the maps of
all effective factors based on model parameters. Mapping of soil characteristics was done by
geo-statistical method. The accuracy of the predicted map was tested with the actual
vegetation map. Predictive maps of E. ceratoides (based on the LR and MDA methods) with
Kappa coefficients as 0.56 and 0.64 had a good accordance with actual vegetation map
prepared for the study area. Kappa coefficient of potential habitat map (based on ENFA
method) of E. ceratoides was 0.85; hence, it had a very good accordance. The results obtained
by all methods showed that this species is distributed in the rangeland with pH as 7.8-8, EC as
0.17-0.26 dc/m and silty-sandy texture in 1600-2200 m elevation. Organic matter in the depth
of 20-80 cm and pH in the depth of 0-20 cm did not significantly influence the differences.
Minimum sampling is needed using these methods which provide worth while data about the
presence of the plant species in the other places.- انتشار مقاله: 22-01-1392
- نویسندگان: Lyla Khalasi Ahvazi,Mohammad Ali Zare Chahouki,Faeze Ghorbannezhad
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Rangeland Science
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,GIS,Subalpine ecosystems,Frequency Ratio,landslide index,Masoleh
- چکیده:
- چکیده انگلیسی: Subalpine ecosystems are highly fragile as compared to biological and
environmental factors. Landslide is one of the ruinous upshots of this ecosystem. One of the
impressionable areas in the cause of natural factor is Masoleh watershed in western Alborz
Mt, (Iran). In order to landslide hazard zonation, landslide index and frequency ratio method
based on twelve causative factors such as slope, slope aspect, land use, lithology, distance
from faults, distance from road, distance from stream, rainfall, range condition, Stream
Power Index (SPI), Component Topographic Index (CTI) and elevation Receiver Operator
Characteristic (ROC) curve analysis method was also used to evaluate the model. The
results showed that geological, physiographical and grassland conditions have an important
role in landslide area. Overgrazing, grazing in forth of season, early grazing, late term
egression, and excess livestock are considered as direct affecting factors on vegetation, so
that they have simultaneous role to make the landslide risk. The verification results via ROC
curve showed that the landslide index model (85%) performed slightly better than the
frequency ratio model (82%). It was concluded that managers and protectors of this
ecosystem can inhibit and conserve the landslide by decreasing the amount of livestock, and
short-term exclosure on critical area, and biomechanical dams in landslide-occurred area.- انتشار مقاله: 03-12-1391
- نویسندگان: Mohammad Hasan Jouri,Mohammad Zare,Diana Askarizadeh,Mona FakhreGhazi,Tina Salarian,Soodeh Miarrostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Rangeland Science
- نوع مقاله: Journal Article
- کلمات کلیدی: density,Shazand,Index species,Associate plants,Distribute pattern
- چکیده:
- چکیده انگلیسی: The aim of this research was to investigate the effect of index species, Astragalus
ammodendron on the associated plants of Agropyron tauri and Bromus tomentellus from
different aspects in Shazand rangeland in southwest of Markazi province. The effects of
species density and distribution pattern and then index species on the soil properties were
studied. Based on the randomized – systematic method, 4 transects with a length of 50 m were
established. To find the relationships between index and associated plants, 30 points were
randomly chosen along the transects and the number of species was counted from these points
to a 50 cm distance in different aspects. Along the transects, the distribution pattern of index
plants and their presence and absence were determined. To find the effects of index species on
soil properties, soil samples were taken and soil properties were determined in laboratory.
Data were analyzed using SPSS software. The results showed that Astragalus ammodendron
density with Agropyron tauri and Bromus tomentellus were similar to the east and west
aspects and near distances. Astragalus ammodendron distribution pattern was randomized
with a tendency toward the clumped pattern. The effect of Astragalus ammodendron on the
soil characteristics was not significant except for the north aspect. Generally, it is concluded
that the effect of Astragalus ammodendron (index species) on Agropyron tauri and Bromus
tomentellus densities was not significant.- انتشار مقاله: 05-10-1390
- نویسندگان: Zahra Mohebbi,Mohammad Jafary,Ali Tavili,Mohammad Ali Zare Chahouki,Sholeh Baghbani,Zeinab Nourikia
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Renewable Energy and Environment
- نوع مقاله: Journal Article
- کلمات کلیدی: Lithium-ion battery,binder,PVDF,artificial graphite,MCMB,CMC (Carboxymethyl Cellulose),SBR (Styrene Butadiene Rubber)
- چکیده:
- چکیده انگلیسی: In recent years, many studies have focused on the active materials of anodes to improve the performance of LIBs, while limited attention has been given to polymer binders, which act as inactive ingredients. However, polymer binders have amazing influence on the electrochemical performance of anodes. Herein, to investigate the binding performance between MCMB artificial graphite and the copper current collector, three binders such as PVDF, MSBR, and CMC+SBR were used to prepare the anode electrodes. The mechanical and electrochemical tests were conducted for different MCMB electrodes. The results show that the water-based binders (CMC+SBR and MSBR) made better adhesion properties for the coating on the current collector in comparison with the organic solvent-based binder (PVDF). MCMB anode fabricated with CMC+SBR binder shows the highest discharge capacity and the best rate performance at various C-rates of 0.2C, 0.5C, and 1C that result in the brilliant electrochemical performance. Therefore, artificial graphite anode materials using cheap aqueous CMC+SBR binder instead of toxic solvent like NMP and expensive PVDF improve electrochemical property and reduce the cost of LIBs.
- انتشار مقاله: 18-03-1398
- نویسندگان: Mohammad Zarei-Jelyani,Shaghayegh Baktashian,Mohsen Babaiee,Rahim Eqra
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Renewable Energy and Environment
- نوع مقاله: Journal Article
- کلمات کلیدی: Lithium-ion battery,Lifetime prediction,capacity loss,cycle-life,operational time
- چکیده:
- چکیده انگلیسی: Accurate lifetime prediction of lithium-ion batteries is a great challenge for the researchers and engineers involved in battery applications in electric vehicles and satellites. In this study, a semi-empirical model is introduced to predict the capacity loss of lithium-ion batteries as a function of charge and discharge cycles, operational time, and temperature. The model parameters are obtained by minimizing the prediction errors of experimental capacity loss for each charge/discharge cycle at 25 oC, 35 oC, and 45 oC.The optimum values of the model parameters are obtained using genetic algorithm, one of the optimization tools in Matlab software. The model accurately predicts the capacity loss of lithium-ion battery for more charge and discharge cycles at 25 °C with an average error of 4 %. The mentioned cycles are used only to validate the prediction.
- انتشار مقاله: 20-03-1398
- نویسندگان: Mohammad Zarei-Jelyani,Mohammad Sarshar,Mohsen Babaiee,Nima Tashakor
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Renewable Energy and Environment
- نوع مقاله: Journal Article
- کلمات کلیدی: Hydroxylation,wettability,Vanadium redox flow battery,Carbon felt,Supporting electrolyte
- چکیده:
- چکیده انگلیسی: Traditional vanadium batteries use pure sulfuric acid as electrolyte, but H2SO4 does not absorb enough vanadium ions to make the electrolyte an efficient energy source. This study investigates the effect of hydroxylation process on electrochemical and operational properties of carbon felt electrode in VOSO4 solution with an optimized supporting electrolyte (a mixture of six parts HCl and 2.5 parts H2SO4). Carbon felt electrode was hydroxylated with mixed acids of H2SO4 and HNO3 in a stainless steel autoclave for 6 h. Then thermal treatment of electrode was performed at 400 oC for 5h. Obtained results of cyclic voltammograms showed that when the carbon felt was hydroxylated, both oxidation and reduction peak currents were increased remarkably and the peak potential separation is decreased from 356 mV to 246 mV, suggesting that the electrochemical activity and the kinetic reversibility on HCF electrode were improved compared to the pristine one. According to results of electrochemical impedance spectra, charge transfer resistance (Rct) was calculated to be 648 Ω for pristine carbon felt. The obtained Rct at hydroxylated electrode (176 Ω) shows a decrease of about 73 % in Rct. Charge-discharge profiles of two cells assembled with the pristine carbon felt (cell A), and hydroxylated carbon felt (cell B) showed that energy, voltage and coulombic efficiencies were significantly improved by using the hydroxylated electrodes inside the cell of vanadium redox flow battery.
- انتشار مقاله: 27-11-1395
- نویسندگان: Mohammad Zarei-Jelyani,Mohsen Babaiee,Abdolmajid Ghasemi,Rahim Eqra
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Plant Physiology and Breeding
- نوع مقاله: Journal Article
- کلمات کلیدی: Grain yield,Durum wheat,Bread wheat,Anatomical features
- چکیده: در آزمایش انجام گرفته برای اولین بار اثر آزوسپیریلوم بر خصوصیات آناتومی محور سنبله در دو گونه گندم نان و دوروم مورد بررسی قرار گرفت. خصوصیات آناتومی برگ پرچم، محور سنبله و نیز عملکرد دو نوع گندم نان و دوروم در تلقیح با باکتری آزوسپیریلوم در آزمایشهای مزرعهای در طول فصلهای رشد 1394 و 1395 تحت شرایط دیم مورد مطالعه واقع شد. عملکرد دانه هر دو نوع گندم در تلقیح با باکتری افزایش یافت و بیشترین میزان افزایش در حدود 8 درصد در گندم نان مشاهده شد. تلقیح با آزوسپیریلوم موجب افزایش تعداد دانه در سنبله گردید. افزایش عملکرد دانه به موجب تلقیح با آزوسپیریلوم در مقایسه با گندم دوروم در گندم نان نمود بیشتری داشت. تغییرات آناتومی ایجاد شده در برگ پرچم و محور سنبله تحت تاثیر کاربرد آزوسپیریلوم نتایج یکسانی را برای دو نوع گندم به همراه نداشت. اگرچه تلقیح با آزوسپیریلوم موجب کاهش تعداد روزنه برگ پرچم به میزان 5/11 درصد شد، اما طول روزنهها را به میزان 6/3 و 5/11 درصد به ترتیب برای گندم نان و دوروم افزایش داد. آزوسپیریلوم به طور معنیدار موجب افزایش 5/12 و 39/13 درصد در مساحت و طول دستجات آوندهای چوبی و 42/14 و 33/33 درصد در مساحت و طول دستجات آوند آبکش شد. همچنین مساحت غلاف آوندی و لایههای مزوفیل در گندمهای تلقیح شده با آزوسپیریلوم به ترتیب به میزان 20 و 5/31 درصد افزایش یافت. تاثیر آزوسپیریلوم بر افزایش مساحت لایههای اپیدرم بالا و پایین برگ در گندم نان بیش از گندم دوروم بود. تغییرات آناتومی ناشی از تاثیر آزوسپیریلوم محدود به برگ پرچم نگردید و چنین تغییراتی در محور سنبله نیز مشاهده شد. گیاهان تلقیح شده با آزوسپیریلوم از مساحت غلاف آوندی و نیز دستجات آوندی چوبی و آبکش بیشتری در محور سنبله برخوردار بودند. به طور کلی تغییرات در عملکرد و نیز خصوصیات آنوتومی به علت کاربرد آزوسپیریلوم در دو نوع گندم یکسان نبود و تاثیر مثبت باکتری در گندم نان بیش از گندم دوروم بود.
- چکیده انگلیسی: In this experiment the effect of inoculation with Azospirillum on the flag leaf and spike rachis anatomical features and also on grain yield and grain weight was investigated for the first time in bread and durum wheats during 2015-2016 growing season under semi-arid condition. The crop yield increased due to the inoculation with Azospirillum with a maximum yield increase of about 8.0 per cent for bread wheat. Azospirillum led to an increase in grain weight per spike. Yield increase due to Azospirillum inoculation was higher for bread wheat than durum wheat. The two wheat species exhibited differences in flag leaf and spike axis anatomic features. Although Azospirillum inoculation decreased the number of flag leaf stomata by 11.5% irrespective of the wheat type, stomatal length of the inoculated plants increased by about 3.6 and 11.5% for bread wheat and durum wheat, respectively. Azospirillum inoculation significantly enhanced the area and length of xylem and phloem vessels by about 12.5 and 12.39% and 14.42 and 33.33%, respectively. Area of the bundle sheath and mesophyll layers of inoculated plants was increased by 20 and 31.5%, respectively. Azospirillum inoculation enhanced the area of upper and lower epidermis of the bread wheat much more than the durum wheat. Anatomic changes due to Azospirillum was not limited to the flag leaf but also extended to the spike rachis and, therefore the inoculated plants had higher area of vascular bundle, xylem vessel and phloem vessel. Overall,the effect of Azospirillum on anatomical features and grain yield of wheat was slightly species specific and it was more pronounced in the bread wheat as compared to the durum wheat.
- انتشار مقاله: 08-09-1395
- نویسندگان: Taiebeh Jafarian,Mohammad Javad Zarea,Adel Siosemardeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Nanostructures
- نوع مقاله: Journal Article
- کلمات کلیدی: AGS cell line,Radiationtherapy,Radiosensitization,Tungsten Oxide Nanoparticles,PBMC Cells
- چکیده:
- چکیده انگلیسی: Radiotherapy which consists of external beam radiotherapy (EBRT) and internal radioisotope therapy (RIT), has a wide usage for treating cancer as clinical trials.This study provides some conditions to prove that tungsten oxide nanoparticles (WO3) is a radiosensitizer.The peripheral blood mononuclear cells (PBMCs) were used to calculate inhibitory concentration (IC).The AGS cell line exposed the concentration of 89.6 µg/mL (IC20) nanoparticle WO3 that was optimal and its radiosensitization was examined in megavoltage photons radiation of 6 MV x-rays. The sensitivity enhancement ratio (SER) and dose enhancement factor (DEF) was determined 1.24 and 1.68 respectively. We described the mechanisms of creating nanoparticles WO3 toxicity and genotoxicity in different concentrations on AGS cell line. The mean size of WO3 NPs by transmission electron microscopy wasmeasured 31.89 3.82 nm.Tungsten oxide Nanoparticles cause to reduce cell viability, remove membrane and damage to DNA. There was a meaningful increasing in damages to DNA and proliferation cell potency and also significantly reducing cell viability in concentrations more than 100 µg/mL.
- انتشار مقاله: 29-08-1397
- نویسندگان: Amin Hassanvand,Mohammad Hossein Zare,Ali Shams,Abolfazlal Nickfarjam,Masood Shabani,Hossein Rahavi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Midwifery and Reproductive Health
- نوع مقاله: Journal Article
- کلمات کلیدی: anxiety,depression,Stress,Birth weight,Level of couple satisfaction
- چکیده:
- چکیده انگلیسی: Background & aim: Low birth weight (LBW) is the center of focus as a cause of many social, emotional, and mental deficiencies. The identification of the probable causes of LBW is considered as an important measure in reducing the prevalence of this health problem. Regarding this, the present study was carried out to compare some of the mental and social traits in the mothers of normal weight newborns and those with LBW neonates.
Methods: This cross-sectional study was conducted on the parents of 400 neonates selected by the proportional sampling technique in Isfahan, Iran. The participants were assigned into two groups of mothers including 200 subjects with LBW neonate and 200 cases with normal birth weight newborns. The data were collected using the Depression, Anxiety, and Stress Scale (DASS-42) developed by Lavibond and Lavibond in 1995 and the couple satisfaction index.
Results: According to the results of the study, there was a significant difference between the two groups of mothers in terms of depression, stress, anxiety, age, medicine consumption, level of education, and marital satisfaction (P<0.001). However, the history of urinary tract infection was not significantly different between the two groups.
Conclusion: As the findings of this study revealed, different aspects of maternal mental health can affect the pregnancy outcome through many pathways. Regarding this, the implementation of the interventions improving the maternal mental health might be useful in the reduction of the neonatal and pediatric mortality and morbidity.- انتشار مقاله: 22-03-1396
- نویسندگان: Mohammad Zare Neyestanak,Masoud Gholamali Lavasani,Gholamali Afrooz
- مشاهده