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51.
52.
Electrically conductive substrates with chromic behavior are prepared using conductive polymer coating of the substrate. Poly
(3-methylthiophene) (P3MT) — coated polyester fabric with specific electrical and chromic properties, for instance electrochromic
and piezochromic behavior, was successfully obtained by chemical polymerization with the help of continuous and speed stirring
technique. The effect of polymerization time, temperature and oxidant concentration on conductivity of the P3MT-coated fabric
was studied. The presence of P3MT particles on the surface of the coated substrate was confirmed by scanning electron microscopy
(SEM), fourier transform infrared (FTIR) and UV-Vis spectroscopy, electrical surface resistivity, pressure and applied voltage
dependence visible reflectance spectrophotometer measurements, and X-ray diffraction (XRD) analysis. The blue shift of c95
nm in wavelength of maximum absorption observed in the reflectance spectra of coated polyester fabric. Under high pressure,
the P3MT-coated polyester fabric demonstrated piezochromism. The coated substrate also showed electrochromic behavior under
an electrical applied voltage of 12 V. 相似文献
53.
Ali Gharghani Zabihollah Zamani Alireza Talaie Nnadozie C. Oraguzie Reza Fatahi Hassan Hajnajari Claudia Wiedow Susan E. Gardiner 《Genetic Resources and Crop Evolution》2009,56(6):829-842
In order to shed light on the role of Iran in apple evolution and domestication, we chose to investigate the relationships
of a collection of 159 accessions of wild and domesticated apples including Iranian indigenous apple cultivars and landraces,
selected wild species, and old apple scion and rootstock cultivars from different parts of the world. The majority of the
wild species belonged to M. sieversii, which is widely believed to be the main maternal wild ancestor of domestic apples, from Kazakhstan and M. orientalis, which is one of the probable minor ancestors of domestic apples, from Turkey and Russia located on the east and west of
Iran, respectively. The accessions were assigned into six arbitrary populations for the purpose of generating information
on genetic parameters. Nine simple sequence repeat (SSR) loci selected from previous studies in apple were screened over DNA
extracted from all the accessions. Results showed that all SSR loci displayed a very high degree of polymorphism with 11–25
alleles per locus. In total, there were 153 alleles across all loci with an average of 17 alleles per locus. The SSR allelic
data were then used for estimation of population genetic parameters, including genetic variation statistics, F-statistics,
gene flow, genetic identity, genetic distance and then cluster analysis using POPGENE 1.32 software. The F-statistics and
gene flow in particular, showed that there was more intra-population than between population variation. The genetic identity
and genetic distance estimates, and the dendrogram generated from the un-weighted pair group arithmetic average (UPGMA) method
of cluster analysis showed that the Iranian cultivars and landraces were more closely related to M. sieversii from Central Asia (east of Iran) and M. orientalis native to Turkey and Russia than to other accessions of Malus species. Also, the old apple cultivars from different parts of the world have a closer genetic relationship to M. sieversii, M. orientalis and the Iranian apples, than to other wild species. Based on these results, we suggest that the Iranian apples may occupy
an intermediate position between the domesticated varieties and wild species. We propose that Iran could be one of the major
players in apples’ domestication and transfer from Central Asia to the western countries. 相似文献
54.
Taiebeh Jafariyan Mohammad Javad Zarea 《Journal of Crop Science and Biotechnology》2016,19(2):167-175
This study aimed to investigate if pretreatment seed with H2O2 affects promoting effect of Azospirillum on plant. The experiment was a factorial combination of two main factors, Azospirillum and hydrogen peroxide (0, 25, 50, and 80%), carried out under field conditions. Soaking seed in various concentrations of H2O2 solution resulted in enhanced stomata density and increased length and histological components of leaf. These changes in histological components were found to be positive since plants of H2O2-soaked seeds (H2O2 pretreatment) had higher fresh and dry weights, seed number per spike, and higher grain yield. Azospiriilum enhanced number of grain spikes-1 and total grain yield by 3% and 7%, respectively. Soaking seeds in 25% H2O2 solution enhanced the promoting effect of Azospirillum on increased vessels area and diameter. Soaking seeds in 50% H2O2 solution resulted in enhanced stimulating effect of Azospirillum on enhanced areas of vascular bundle and upper epidermis. The promoting effect of Azospirillum on the area of lower epidermis was largest when seed was pretreated with 80% H2O2. All three concentrations of H2O2 used had the same effect on Azospirillum–inoculated plant in terms of leaf area and chlorophyll a. Soaking seed in 80% H2O2 solution and then inoculated with Azospirillum resulted in the highest grain yields. 相似文献
55.
Hamid-Reza Fallahi Gholamreza Zamani Mokhadereh Mehrabani Mahsa Aghhavani-Shajari Alireza Samadzadeh 《Journal of Crop Science and Biotechnology》2016,19(1):77-84
Mother corm size is the most important factor for production of replacement corms, flower, and stigma yield in saffron. In semi-arid regions, water shortage is a deterrent agent for appropriate corm growth of saffron. Therefore, in this experiment the effects of six levels of superabsorbent polymer (SAP) including 0, 10, 20, 30, 40, and 50 kg ha-1 was investigated on growth indices of replacement corms of saffron. For this purpose, an experiment was evaluated at the research farm of the Saffron Research Group, Sarayan Faculty of Agriculture, University of Birjand, Iran, during 2013-2015. Results showed that SAP application did not considerable effect on corm growth indices in the first life cycle of saffron. Nevertheless, consumption of 30-40 kg ha-1 SAP somewhat improved the number and total weight of replacement corms per clone. In the second life cycle of saffron, the positive impact of SAP was clearly observed on the growth of replacement corms. The application of 40 kg ha-1 SAP increased the amount of number of replacement corms per clone by 13%, total weight of replacement corms per clone by 36%, and scale weight of corms per clone by 50% compared with control. In addition, the amount of mean weight of replacement corms and mean number of buds per corm in treatment of application of 40 kg ha-1 SAP were 29 and 27% higher than the control treatment, respectively. SAP application decreased the amount of non-standard (< 8 g) corm production while significantly increased the percentage of corms with standard weight. Overall, the increasing effect of SAP application on corm weight, bud number, and standard corm yield was higher than the number of produced corms per clone. In addition, water-use efficiency in SAP application treatments (6.1 kg standard corm m-3) was more than the control (4.34 kg m-3) treatment. In total, SAP application is an appropriate strategy for production of standard saffron corms in semi-arid regions. 相似文献
56.
Talebi J Moghaddam A Souri M Mirmahmoudi R 《Tropical animal health and production》2012,44(2):355-360
The present study aims were to determine the profiles of changes in progesterone (P4) and 17-β-estradiol (E2) in the peripheral
blood of Markhoz goat (Iranian Angora) during estrous cycle, gestation, and parturition throughout natural breeding season.
Gestation length averaged 145.3 ± 0.8 days, and the litter size was 1.1 ± 0.1. Birth weight ranged 2.4–2.8 and 1.5–2.5 kg
in male and female kids, respectively. The mean estrous cycle lengths were 20.3 ± 0.4 and 20.9 ± 0.4 days for PGF2α-induced and natural cycles, respectively. Blood sampling was carried out daily during estrous cycle and weekly during gestation
till parturition. E2 attained higher level (24.7 ± 2.15 pg mL−1) at estrus phase and dropped down to the lower level (18.80 ± 1.16 pg mL−1) within 3 to 4 days post-estrus. Concomitantly, P4 started to increase from the mean basal value of 0.5 ± 0.03 ng mL−1 on day 0 to 6.88 ± 0.95 ng mL−1 on day 6 of estrous cycle and reached the peak value of 12.8 ± 0.61 ng mL−1 on day 12. From day 15, a decline was observed in P4 values till the end of the cycle. P4 remained at lower concentrations
for 20–50 days of gestation, then increased and reached to its maximum level (13.51 ± 0.279 ng mL−1) in week 15 and returned again to its basal values within 1–2 weeks before parturition. The results will be discussed in
terms of the usage of steroid hormone profile in several assisted reproductive technologies. 相似文献
57.
Javad Seyedmohammadi Hamid Reza Matinfar 《Communications in Soil Science and Plant Analysis》2018,49(18):2301-2314
Soil cation exchange capacity (CEC) is a main criterion of soil quality and pollutant sequestration capacity. This research was carried out to evaluate cokriging prediction map of soil CEC spatial variability with the principal components derived from soil physical and chemical properties. Two hundred and forty-seven soil samples were collected that 75% of them were used for training soil CEC and 25% for testing of prediction. The first principal component (PC1) was highly correlated with soil CEC (r = 0.81, P < 0.01), whiles there was no significant correlation between CEC and PC2 (r = -0.19). Then, the PC1 was used as an auxiliary variable for the prediction of soil CEC in cokriging method. The determination coefficient (R2) of cross-validation for the test dataset was 0.47 for kriging and 0.71 for cokriging. Therefore, according to the results, principal components that have the highest positive and significant correlation with the dependent variable have the most potential for cokriging prediction. 相似文献
58.
In this study, for accuracy and cost an optimal inventory method was examined and introduced to obtain information about Zagros forests, Iran. For this purpose,three distance sampling methods(compound, order distance and random-pairs) in 5 inventory networks(100 m × 100 m, 100 m × 150 m, 100 m × 200 m,150 m × 150 m, 200 m × 200 m) were implemented in GIS environment, and the related statistical analyses were carried out. Average tree density and canopy cover in hectare with 100% inventory were compared to each other.All the studied methods were implemented in 30 inventory points, and the implementation time of each was recorded.According to the results, the best inventory methods for estimating density and canopy cover were compound150 m × 150 m and 100 m × 100 m methods, respectively. The minimum amount of product inventory time per second(T), and(E%)2 square percent of inventory error of sampling for the compound 150 m × 150 m method regarding density in hectare was 691.8, and for the compound 100 m × 100 m method regarding canopy of 12,089 ha. It can be concluded that compound method is the best for estimating density and canopy features of the forests area. 相似文献
59.
The biodiversity of arbuscular mycorrhizal fungi (AMF) was surveyed in the Kolm region of Iran in three adjacent sites, a natural stand, a 10-year-old and a 15-year-old plantation of Amygdalus scoparia. To date, there have been few studies of AMF biodiversity in Iran, especially in the western forests of the country. For this study, soil and root samples were taken from A. scoparia rhizosphere soil in spring and autumn. Almost half of the root length was colonized by AMF. We identified 13 AMF species belonging to Glomeraceae, Claroideoglomeraceae or Diversisporaceae. The three plantations differed in terms of soil electrical conductivity, organic C and P. Spore density was significant correlated with P concentration. Root length colonization was correlated only with soil Ca. Species diversity and richness were significantly correlated with soil N, P, organic C and spore density. AMF diversity in 15-year-old plantations was more similar to that in the natural stand than in the 10-year-old plantation. We confirmed that a 15-year-old plantation is not similar in terms of AMF colonization to natural stands. We conclude that more than 15 years are required for AMF colonization of plantations to resemble that of natural stands. 相似文献
60.
Mohammad Javad Amiri Ali Shabani 《Communications in Soil Science and Plant Analysis》2017,48(14):1669-1683
Leaf Area (LA) is a key index of plant productivity and growth. A multiple linear regression technique is commonly applied to estimate LA as a non-destructive and quick method, but this technique is limited under the realistic situation. Thus, it is indispensable to elaborate new models for estimation. In this research, the performance of the Adaptive Neural-Based Fuzzy Inference System (ANFIS) in predicting the LA of 61 plant species (C) was investigated. Four parameters including leaf length (L), leaf width (W), C, and specific coefficient (K) for each plant were selected as input data to the ANFIS model and the LA as the output. Seven different ANFIS models including different combinations of input data were constructed to reveal the sensitivity analysis of the models. The normalized root mean square error (NRMSE), mean residual error (MRE), and linear regression were applied between observed LA and estimated LA by the models. The results indicated that ANFIS4-K2min which employed all input data was the most accurate (NRMSE = 0.046 and R2 = 0.997) and ANFIS1 which employed only the K input was the worst (NRMSE = 0.452 and R2 = 0.778). In ranking, ANFIS4-K2ave, ANFIS4-K1min, ANFIS4-K1ave, ANFIS3, and ANFIS2 ranked second, third, fourth, fifth, and sixth, respectively. The sensitivity analysis indicated that the predicted LA is more sensitive to the K, followed by L, W, and C. The results displayed that estimations are slightly overestimated. This study demonstrated that the ANFIS model could be accurate and faster alternative to the available laborious and time-consuming methods for LA prediction. 相似文献