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81.
This study, we synthesized graphite-nanoflakes (GNFs) by acid treatment and thermal shock and then using the ultrasonic irradiation technique to exfoliate flake-carbon. The SrFe12O19 nanoparticles (NPs) were coated by co-precipitate method on GNFs after by alkaline treatment. Finally nanocomposite (GNF/SrFe12O19/PTh) was prepared by in-situ oxidative polymerization method in presence of thiophene (Th) as monomer. The magnetic and electrical conducting properties of the resulting nanocomposites were measured by using vibrating sample magnetometer and standard four-point-probe method, respectively. The synthesized nanocomposites were characterized by X-ray diffraction (XRD) and fourier transform infrared spectra (FTIR). In addition, morphological analyses were investigated by scanning electron microscopy (SEM). A minimum reflection loss (RL) of GNFs/SrFe12O19/PTh with 50 % wt GNFs/SrFe12O19 as core were observed ?28 and ?39 dB at 9.7 and 12 GHz for a 1.5 mm thickness. The results indicated that we can perform good microwave shielding in X-band (8–12 GHz) by these nanocomposites.  相似文献   
82.
One of the features of the forest dwellers in the Zagros region of Iran is their dependence on non-timber forest products (NTFPs). These products can play an important role in the livelihood of households located in the forest. The present study aims to determine the most important sources of forest dwellers’ incomes in the northern Zagros in terms of three income groups (lower, middle, and higher), to assess how changes in income are related to types of NTFPs harvested, and to investigate the most significant socio-economic factors determining absolute and relative household revenue from NTFPs. Income in higher- and middle-income groups come predominantly from border trade between Iran and Iraq, comprising 50 and 44 % of relative income, respectively. The main source of income for the lower-income group is remittance and government interest (such as cash subsidies), comprising 31 % of total household annual income. The relative income from NTFPs depends on the income group, varying between 10 and 21 %. Relative income from NTFPs (such as oak acorns, firewood, Gazoo, and Mazooj) for lower-income households is significantly higher than in middle- and higher-income households (p < 0.05). Feed used for grazing livestock in the forest is the most important type of NTFPs in this area, and its benefit in the higher-income group is significantly higher than that for groups with middle and lower income. A similar result is achieved for tree fodder. Relative income from the NTFPs is positively related to number of household members and negatively related to the average education of adult members of the household, the relative income from border trade, and the relative income from agriculture. Our results support our hypothesis that if there is access to other sources of income for forest dwellers, their dependence on forests would be reduced.  相似文献   
83.
Fisheries Science - Illipe Shorea macrophylla is a riverine fruit naturally eaten by Malaysian mahseer Tor tambroides and other riverine cyprinids. The effects of crude illipe oil on the growth...  相似文献   
84.
Ramularia ranunculicola sp. nov. (Mycosphaerellaceae) is described from Iran on Ranunculus muricatus and compared with other species reported on Ranunculus spp. Ramularia carletonii on Lactuca tuberosa and R. nagornyi on Centaurea solstitialis are newly reported from Iran, and Picris strigosa is a new host for R. picridis (= R. inaequalis s. lat.).  相似文献   
85.
Zinc (Zn) desorption is an important process to determine Zn bioavailability in calcareous soils. An experiment was performed to assess the pattern of Zn release from 10 calcareous soils of orange orchards, southern Iran and the soil properties influencing it. For Zn desorption studies, soil samples were extracted with diethylene triamine penta-acetic acid solution at pH 7.3 for periods of 0.083–48 h. Suitability of seven kinetic models was also investigated to describe Zn release from soils. Generally, Zn desorption pattern was characterized by a rapid initial desorption up to 2 h of equilibration, followed by a slower release rate. The simple Elovich and two-constant rate kinetic models described Zn release the best, so it seems that Zn desorption is probably controlled by diffusion phenomena. The values of the rate constants for the superior models were significantly correlated with some soil properties such as soil organic matter (SOM) content, cation exchange capacity (CEC), and soil pH, whereas carbonate calcium equivalent and clay content had no significant influence on Zn desorption from soils. SOM had a positive effect on the magnitude of Zn release from soils, while soil pH showed a negative effect on Zn desorption. Furthermore, the initial release rate of soil Zn is probably controlled by CEC in the studied soils. Finally, it could be concluded that SOM, CEC, and soil pH are the most important factors controlling Zn desorption from calcareous soils of orange orchards, southern Iran.

Abbreviations: Soil organic matter (SOM); Cation exchange capacity (CEC); Calcium carbonate equivalent (CCE); Zinc (Zn).  相似文献   

86.
To study the genetic variation, heritability and genetic correlations of some agro-morphological traits in tall fescue, 25 parents from a genetically broad-base germplasm were polycrossed and their respective half-sib families were generated. Clonally propagated parents and their half-sib families were grown as spaced single plants using a randomized complete-block design with three replications, and observed for seven traits in 2006 and 2007. The estimates of broad-sense heritability were moderate to high for the traits studied. Narrow-sense heritability estimates from analyses of progenies and from regression of half-sib (HS) progenies on parents suggested that genetic variation for these traits was largely controlled by additive gene action. Association of dry matter yield (DMY) with plant height, number of fertile shoot, curbs width and spring growth was positive and significant. With the exception of number of days to pollination, correlation coefficients of the traits between the parents and offspring were not significant. Based on parent-offspring regression, genetic gain from selection for DMY was high, demonstrating genetic potential for improving this trait. Overall, there was high genetic variation and moderate heritability for most traits in the tall fescue populations evaluated. In conclusion, to improve herbage yield, selection would be more effective based on forage yield components.  相似文献   
87.
The study appraised the effects of Carotino oil on in vitro rumen fermentation, gas production, metabolism and apparent biohydrogenation of oleic, linoleic and linolenic acids. Carotino oil was added to a basal diet (50% concentrate and 50% oil palm frond) at the rate of 0, 2, 4, 6 and 8% dry matter of the diet. Rumen inoculum was obtained from three fistulated Boer bucks and incubated with 200 mg of each treatment for 24 h at 39°C. Gas production, fermentation kinetics, in vitro organic matter digestibility (IVOMD), volatile fatty acids (VFA), in vitro dry matter digestibility (IVDMD), metabolizable energy and free fatty acids were determined. Carotino oil did not affect (P > 0.05) gas production, metabolizable energy, pH, IVOMD, IVDMD, methane, total and individual VFAs. However, Carotino oil decreased (P < 0.05) the biohydrogenation of linoleic and linolenic acids but enhanced (P < 0.05) the biohydrogenation of oleic acid. After 24 h incubation, the concentrations of stearic, palmitic, pentadecanoic, myristic, myristoleic and lauric acids decreased (P < 0.05) while the concentration of linolenic, linoleic, oleic and transvaccenic acids and conjugated linoleic acid (CLAc9t11) increased (P < 0.05) with increasing levels of Carotino oil. Carotino oil seems to enhance the accumulation of beneficial unsaturated fatty acids without disrupting rumen fermentation.  相似文献   
88.
Ultra fine fibers were electrospun from regenerated silk fibroin/formic acid solution. Effect of some process parameters on the morphology, diameter and variation in fiber diameter of electrospun fibers were experimentally investigated. Scanning electron microscope was used for the measurement of fiber diameter. Fibers with diameter ranging from 80 to 210 nm were collected depending on the solution concentration and the applied voltages. Response surface methodology (RSM) was used to obtain a quantitative relationship between selected electrospinning parameters and the average fiber diameters and its distribution. It was shown that concentration of silk fibroin solution had a significant effect on the fiber diameter and the standard deviation of the fiber diameter. Applied voltage had no significant effect on the fiber diameter and its standard deviation.  相似文献   
89.
This study was carried out to evaluate the antioxidative potential and quality of the meat of African catfish fed mulberry foliage extract (MFE). A total of 360 juvenile African catfish (8.4 ± 0.2 g) were fed four diets namely, basal diet (control), MFE‐2 (2 g MFE kg?1), MFE‐5 (5 g MFE kg?1) and MFE‐7 (7 g MFE kg?1) for 60 days. At the end of the experiment, muscles were excised, vacuum‐packaged and conditioned for 0, 7 and 14 days in a chiller (4°C). The meat from fish fed MFE‐5 and MFE‐7 had significantly (P < 0.05) greater total phenols content than the other dietary groups. This value reduced (P < 0.05) during storage. The DPPH‐scavenging effect of MFE‐7 increased (P < 0.05) compared with the others. It decreased (P < 0.05) during storage. The lowest POV was revealed (P < 0.05) in MFE‐7. The 2‐thiobarbituric acid‐reactive substances (TBARS) and peroxide value (POV) increased (P < 0.05) during storage. The pH value was significantly (P < 0.05) higher in MFE supplemented diets than in the control group. It is concluded that MFE at the concentration of 7 g kg?1 DM is potential dietary antioxidant supplements, to improve the quality of fish meat.  相似文献   
90.
The present study aimed to assess the effect of contrasting levels of molecular and phenotypic diversity among polycross parents of orchardgrass on the performance of synthetic progeny with respect to physiological responses and drought tolerance. Four polycross groups each composed of six parental plants were evaluated under normal irrigation and drought stress conditions. A number of 923 inter simple sequence repeats and sequence related amplified polymorphism markers and several phenotypic traits were used to select contrasting levels of diversity (high and low) in parental genotypes. Highly significant correlation was observed between molecular distance and progeny performances at both normal irrigation and drought stress conditions. High molecular diversity among polycross parents led to a significant yield advantage of first generation progeny with averages of 34.40% for normal irrigation and 48.10% for drought stress conditions. Also crosses between genetically distant parents produced progeny with considerable drought tolerance and yield stability. Positive associations between phenotypic distance of parents and progeny performance were found for most physiological traits at both moisture regimes but phenotypic distances had weak association with forage yield, stress tolerance index and yield stability of progeny. Significant associations between drought tolerance index and some physiological traits confirmed the importance of these traits in conferring drought tolerance of orchardgrass. Our results underscore the effectiveness of marker‐assisted polycross breeding to improve drought tolerance and yield stability through physiological traits in orchardgrass.  相似文献   
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