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31.
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
32.
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
33.
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
34.
This experiment was conducted to evaluate the effects of three nutrient recipes containing different concentrations of macronutrients in the vegetative stage [Vegetative Nutrient Solution: (VNS-I, VNS-II, and VNS-III)] and two nutrient recipes in reproductive stage [Reproductive Nutrient Solution: (RNS-I and RNS-II)], on physiological and biochemical parameters of strawberry ‘Paros’ in a soilless system. The results indicated the significant effects of nutrient solution on the photosynthetic capacity, yield, minerals uptake and titratable acidity of strawberry fruits. In the other hand fruit total soluble solids affected by vegetative nutrient solution. The highest yield was obtained under application of lowest level of minerals. Vegetative growth including leaf number and leaf area, as well as total chlorophyll were the highest as potassium (K+), calcium (Ca2+), and nitrogen (N) concentrations were increased. The highest content of N and Ca2+ uptake were in VNS-III × RNS-I formulation. Additionally, the highest vitamin C was in VNS-I formulation. Moreover, the most firmed fruits and the highest post-harvest shelf life of fruits were produced in VNS-III × RNS-I formulation. 相似文献
35.
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
36.
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
37.
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
38.
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
39.
Mehran Mehri Javad Pourreza Ghorbanali Sadeghi 《Tropical animal health and production》2010,42(3):439-444
Pearl millet grain could be considered as an alternative feed ingredient for poultry. In a 12 wks experiment, the performance
of laying hens fed diets containing pearl millet were compared with those fed diets containing corn. Maize grain was replaced
by pearl millet on an equal-weight at either 0, 25, 50, 75 or 100%. Results showed that use of 25, 50 and 75% of pearl millet
in place of maize in the diet resulted in similar (P > 0.05) hen-day egg production, egg mass, egg weight, feed intake and
feed conversion ratio to those of control group. Totally replacement of maize grain with pearl millet significantly (P < 0.05)
reduced all production parameters. Egg quality parameters did not affect by using pearl millet in the diet. These results
showed that maize grain can be replaced by pearl millet up to 75% in the diets of laying hens without any adverse effect on
hen performance or egg quality. 相似文献
40.
Numerical simulating the tensile behavior of 1×1 rib knitted fabrics using a novel geometrical model
A geometrical model to predict the tensile properties of conventionally knitted 1×1 rib fabric was created to be used for technical applications. Tensile stress-strain curve was numerically simulated in course and wale directions, using FEM method. The accuracy of the used geometrical model has been estimated comparing the simulated tensile stress-strain curve of the model to the measured one. The results showed that the stress-strain curve obtained from simulating method is very close to the experimental one. 相似文献