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1.
We analyzed the structure of pollarded oak forest and biometric indices of pollarded oak species in relation to aspect in northern Zagros forests, western Iran. A number of 319 circular plots (0.1 ha) were established using a systematic random method over the study area. In each plot, for all trees (diameter at breast height ≥5 cm) diameter was measured and tree species was recorded. Total height, trunk height, and major and minor diameter axis of the crown of two trees in each plot (nearest tree to the center of the plot and the largest tree in term of diameter) were measured. As the dispersion of slope and altitude classes in the study area were identical, the effect of these factors was assumed to be constant. To evaluate the effect of aspect on biometric indices of oak trees a comparison was used for each oak species separately. The results indicated that the forest species composition differed statistically significant in main aspects except for easterly and westerly aspects (P < 0.01). The diameter of similar oak trees was significantly different except for Lebanon oak in northerly and southerly and Gall oak in easterly and westerly aspects (P < 0.01), but there was no significant difference between the total height and crown area of similar oak species in different aspects. Differences in diameter, height, and crown area distributions showed a significant difference in main aspects. The basal area and tree density in northerly and southerly aspects were significantly different (P < 0.05). 相似文献
2.
AbdolMajid Valipour Behrooz Heidari Hamidreza Vaziri S. Mohsen Asghari 《Reproduction in domestic animals》2021,56(10):1349-1357
Kisspeptin, upstream of the hypothalamic-pituitary-gonadal axis, play an essential role in the reproductive process. In the present study, the effect of different types of kisspeptin, including goldfish (Carassius auratus) kiss1 kisspeptin (Kiss1), human kisspeptin (Hkiss) and their combination (Kiss1+H) on the reproductive-related genes (kiss1, Kissr and Cyp19) of adult female goldfish was investigated in comparison with Ovaprim (a synthetic GnRH hormone). Kiss1 and Hkiss were synthesized using a solid-phase synthesis approach. Peptides were injected at a dose of 100 μg/kg body weight. The brain and ovarian tissues of samples were separated for histological studies 24 hr post-injection. The expression of the kiss1, Kissr and Cyp19 genes was measured by RT-PCR. The results showed a significant increase in expression of the reproductive-related genes. Histological analysis revealed higher number of mature oocytes in kisspeptin treated groups compare to other ones. In conclusion, Hkiss and Kiss1+H are the most effective peptides in oocyte maturation and expression of reproductive-related genes. In addition, it seems that kisspeptins in other domestic animals can be used to stimulate the hypothalamus-pituitary-gonadal axis. 相似文献
3.
The improvement of yarn properties is an obligatory but a difficult task to get a quality product and to enhance efficiency of production processes. For this purpose it is necessary to create a close compatibility between yarn characteristics and subsequent processes requirements. A survey of the literature will reveal that, there are various researches in which statistical approaches have been employed to introduce appropriate yarn quality parameters in accordance with the requirements of next processes. But, mentioned analysis is a multi-criteria decision making where the differences between the values of the yarn parameters and preferences of the producer about yarn characteristics to get a product with defined properties should be considered. However, this goal can not be achieved by using statistical methods. Therefore, this paper makes an attempt to apply preference ranking organization method for enrichment evaluations (PROMETHEE) for the first time in the field of textile science in selecting suitable drawing frame variables for 30 Ne rotor spun yarn intended to be used for weft knitting process. The performances of three variables in a drawing frame were evaluated based on seven quality parameters of forty eight rotor spun yarns using this algorithm. Final ranking was elicited in accordance with PROMETHEE method. Consequently, sensitivity analysis was conducted to assess the stability of the proposed final ranking. 相似文献
4.
Mohammad Valipour 《Archives of Agronomy and Soil Science》2013,59(12):1641-1660
The aim of this paper is the estimation of area equipped for irrigation in the world in 2035 and 2060 using studies of agricultural water management during 1962 to 2011. Among all presented data in the Food and Agriculture Organization of the United Nations database, 10 indexes were selected (due to more importance and more availability for all the regions in the world). These indexes are permanent crops to cultivated area (PC, %), rural population to total population (RP, %), total economically active population in agriculture to total economically active population (LF (Agric), %), human development index (HDI), national rainfall index (NRI, mm year?1), value added to gross domestic product (GDP(Agric)) by agriculture (%), irrigation water requirement (IWR, mm year?1), percent of total cultivated area drained (D, %), difference between NRI and irrigation water requirement (mm year?1), and area equipped for irrigation to cultivated area (AI, %). These indexes were analyzed for all five regions in the study area and the amount of area equipped for irrigation to cultivated area (10th index) was estimated by three different scenarios and using the other nine indexes. The results show that changes of area equipped for irrigation are 12.1% to 70.7% and 29.0% to 99.9% from 2011 to 2035 and 2060, respectively. 相似文献
5.
Following our previous research [1], an extensive investigation on the effects of four mercerization treatment parameters namely, alkali concentration, time of treatment, bath temperature, and mercerization tension on dimensional properties of plain knitted fabric produced from cotton yarn is presented in this paper. Numerical values of constant geometry of the dry relaxed, wet relaxed, and mercerized samples were calculated according to Munden’s equations. Study shows that the area geometry constant values (K s ) achieved after mercerization treatment was higher than values obtained for the samples subjected to dry and wet relaxations. Also, ANOVA test confirmed significant effects of each parameter itself and their interactions on dimensional properties of the fabric samples. Based on the results, applying less value of tension improves dimensional stability of the fabric but not for the samples mercerized in higher values of three other parameters. The alkali concentration had an optimum value in mercerization treatment. In mercerizing conditions carried out in high temperature and long time, lower alkali concentration is more efficient. Increasing time of treatment leads to achieve higher K s value when lower value of alkali concentration is used. Most of the samples mercerized in bath temperature of 40 °C had the highest K s . At the end of the research a statistical model was derived to predict the area geometry constant of the fabric. 相似文献
6.
Vahid Shakeri Siavashani Peiman Valipour Ezzatollah Haghighat 《Fibers and Polymers》2014,15(4):729-735
In this study, the effect of corona discharge treatment on the physical and mechanical properties of bleached cotton and polyester-cotton fabrics were investigated. For this purpose, the samples were treated by corona discharge at two levels of voltage 5 and 10 kV, and at various duration times of plasma, ca. 1.4, 2.1 and 3.5 min. The corona discharge treatment was applied on the fabric samples before and after bleaching treatment. The results show that the corona influences on the surface morphology, breaking strength, air permeability, abrasion resistance, and pilling of cotton and polyester-cotton fabrics. Moreover, the levels of voltage and duration of plasma have a different effect on the properties of fabrics. 相似文献
7.
Mohammad Valipour Mirkhalegh Ziatabar Ahmadi Mahmoud Raeini-Sarjaz Mohammad Ali Gholami Sefidkouhi Ali Shahnazari Ramin Fazlola 《Archives of Agronomy and Soil Science》2013,59(5):657-678
The present paper aims to estimate the areas equipped for irrigation and desirability of agricultural water management in the world. For this purpose, all necessary information was gathered from Food and Agriculture Organization and checked using World Bank Group. The selected 18 indices were analysed for all 26 regions in the area studied, and the extent of area equipped for irrigation to cultivated area was estimated by 2 different formulas and other 9 indices. In addition, an average index was calculated using various methods to assess region conditions for agricultural water management. The results show that Central Asia is the best region for agricultural water management and the value of relative error is less than 20%. The capability of irrigation and drainage systems was studied using other eight indices with more limited information. The results indicated that trial-and-error policies should be avoided and expert comments be applied to irrigation systems for any crop. 相似文献
8.
Mohammad Valipour 《Archives of Agronomy and Soil Science》2013,59(9):1247-1271
The aim of this paper was to study the land use index (equipped area for irrigation per cultivated area, AI) and irrigation management in Asia and Oceania during past decades. For this purpose, all necessary information was collected from Food and Agriculture Organization of the United Nations (FAO). Among all presented data in the FAO database, 10 indices were selected. These indices were analysed for all 64 countries in Asia and Oceania, and the extent of AI was estimated by two different methods and other 9 indices. The results show that using all the 9 indices, the value of relative error will be less than 20%. Prioritization of the indices has shown that national rainfall index (NRI) and the difference between NRI and irrigation water requirement had a highlighted effect on the estimation of AI. 相似文献
9.
Mohammad Valipour 《Archives of Agronomy and Soil Science》2013,59(5):679-694
This study aims to assess radiation-based models versus the FAO Penman–Monteith (FPM) model to determine the best model using linear regression under different weather conditions. The reference evapotranspiration was estimated using 22 radiation-based methods and was compared with the FPM. The results showed that the Stephens method estimates the reference evapotranspiration better than other methods in the most provinces of Iran (nine provinces). However, the values of R2 were more than 0.9930 for 24 provinces of Iran. The radiation-based methods estimated the reference evapotranspiration near the Caspian Sea better than other regions. The most precise methods were the Berengena–Gavilan, Modified Priestley–Taylor, and Priestley–Taylor methods for the provinces ES (center of Iran), GI and GO (north of Iran) and the Stephens–Stewart method for IL (west of Iran). Finally, a list of the best performance of each method has been presented to use other regions and next research steps according to the values of mean, maximum, and minimum temperature, relative humidity, solar radiation, elevation, sunshine, and wind speed. The best weather conditions to use radiation-based equations are 23.6–24.6 MJ m?2 day?1, 12–20°C, 18–24°C, 5–13°C, and <180 hour month?1 for solar radiation, mean, maximum, and minimum temperature, and sunshine, respectively. 相似文献
10.
Laser treatment is one of the technologies which are able to eliminate all the adverse effects on the environment caused by
chemical treatment commonly used in textile finishing. In this research, we investigated the use of laser treatment for the
purpose of wool felting shrinkage control, and compared its effectiveness with that of the traditional chlorination treatment
method. The wool fabric was exposed to an industrial laser at two different power levels and two sweep speeds. We found that
upon selecting the appropriate treatment parameters, the laser treatment is effective in reducing felting shrinkage of wool
fiber by its etching effects on the scales of the wool fiber as shown by the scanning electron micrographs. Too high energy
exposure of the wool fiber by laser radiation causes excessive fabric strength loss. We also found that the laser-treated
wool has felting shrinkage reduction similar to that treated using the traditional chlorination procedure. The laser technology
presents an alternative wool processing method to replace the tradition chlorine treatment method. If this technology can
be applied to wool felting-proof finishing on a commercial scale, it will significantly benefit the environment by completely
elaminating the harzardous chlorine compounds currently by the industry. 相似文献