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101.
Considering increasing rate of Iran population and consumption of wood panels, the authors investigated the per capita consumption of wood panels during the years from 1997 to 2007. The exponential smoothing method was used to obtain a per capita consumption pattern of wood panels in Iran for estimating demand of wood panels by the year of 2012. Results show that the consumption of particleboard, fiberboard, and medium density fiberboard in Iran will increase by 33%, 72% and 107 %, respectively, by the year of 2012; however, the consumption of plywood will increase only by 7% by 2012. The deficient amount of wood panels in Iran is estimated over 1400000 m3. The results of this study provide the technique reference for planners of wood panel industries in Iran in capital investment decisions. 相似文献
102.
Majid Azizi 《林业研究》2008,19(4):323-328
The objective of this research is to design a method for an appropriate alternative to supply poplar wood as raw material for wood and paper factories in Iran.Due to the destruction of the forests and lack of proper plantation,replacement of the forest wood by the fast growing wood is vital to satisfy all requirements of these factories.A hierarchy was used to prioritize benefits,opportunities,costs and risks (BOCR) using the Analytic Hierarchy Process (AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy was also created and prioritized by applying the Analytic Network Process (ANP).A total of four major control criteria in the system are prioritized where each one controls a network structure evaluated by using ANP.The final synthesis results of the system showed that internal poplar tree farming supplied by the forest product factories was the best choice among three potential alternatives (factory procurement,external procurement and mix procurement). 相似文献
103.
Narjes Amirchakhmaghi Hamed Yousefzadeh Batool Hosseinpour Kambiz Espahbodi Majid Aldaghi Amandine Cornille 《Genetic Resources and Crop Evolution》2018,65(4):1255-1268
Investigating population genetic structure and diversity, and resistance to pathogens in crop wild relatives are key steps to assess appropriate conservation and breeding programs. The Caucasian wild apple (Malus orientalis Uglitzk.) is an emblematic fruit tree of the Hyrcanian forest and is supposed to be a contributor to the cultivated apple genome (Malus domestica Borkh. Yet, no study has investigated its population structure, diversity and susceptibility to the two main pathogens of apples, the apple scab (Venturia inaqualis) and the powdery mildew (Podosphaera leucotricha). Here, we investigated population genetic structure and diversity of M. orientalis in the Hyrcanian forest as a mean to identifying future targeted populations for apple conservation and breeding programs. We genotyped using multilocus microsatellite 100 M. orientalis trees sampled in 14 sites. These trees were also screened for presence/absence of six (Rvi6, Vr, Rvi4, Rvi15, Rvi5 and Rvi11) and three (Pl-1, Pl-w, Pl-d) resistance genes to the apple scab and the powdery mildew respectively. Our results showed significant but weak between-site genetic differentiation and isolation by distance pattern suggesting substantial historical gene flow for M. orientalis in this area. We also detected a West-Eastern genetic structure across the Hyrcanian forest with five main populations showing admixture. We also showed a high diversity of resistance genes to apple scab across sites; in contrast, we only found one resistance gene to powdery mildew. These results are a first glimpse to settle wild apple conservation programs in Iran and pinpoint Iranian wild apple populations as an untapped source for apple breeding. 相似文献
104.
105.
Latifah Omar Nik Muhammad Abdul Majid 《Communications in Soil Science and Plant Analysis》2018,49(14):1795-1813
A field study was carried out from April 2014 to August 2014 for two consecutive planting cycles of Zea mays L. on Nyalau Series (Typic Tualemkuts) to determine the short-term effects of co-application of chemical fertilizers, rice straw compost, and clinoptilolite zeolite on (i) ammonium adsorption and desorption, (ii) nitrogen, phosphorus, and potassium uptake and use efficiency, and (iii) yield of Zea mays L. (cobs). Amending urea with rice straw compost and clinoptilolite zeolite improved nitrogen use efficiency because of temporary adsorption and desorption of ammonium on the exchange sites of compost and clinoptilolite zeolite. Combined use of chemical fertilizers, rice straw compost, and clinoptilolite zeolite enhanced uptake of nitrogen, phosphorus, potassium, calcium, and magnesium. Co-application of chemical fertilizers, rice straw compost, and clinoptilolite zeolite can improve the availability of soil nutrients. This approach can also improve nutrient use efficiency and yield of Zea mays L. 相似文献
106.
Untreated polyethylene terephthalate has limitation in some medical applications, such as wound dressing due to the hydrophobic property. Thereby, Tragacanth Gum (TG) as a natural polysaccharide utilized in polymer solution led to novel semi-bionanofibers of PET/TG blends (15:1, 15:2 and 15:3) through electrospinning method. Fourier transform infrared spectroscopy results confirmed the existence of hydrophilic groups of TG such as hydroxyl groups. Moreover, twice water uptake of PET/TG comparing with PET nanofibers indicated the hydrogel properties, also PET/TG nanofibers possessed high surface wettability through reduction of contact angle from 113 to 0°. Further, differential scanning calorimetry analysis indicated the alteration in the crystalline structure of PET/TG nanofibers that led to faster degradation in various pH values. The SEM images of PET/TG nanofibers displayed the greater average diameter with increasing TG content (283 nm) comparing with PET nanofibers (193 nm). Also introducing more TG in the nanofibers exhibited lower mechanical properties. 相似文献
107.
Aminoddin Haji Majid Nasiriboroumand Sayyed Sadroddin Qavamnia 《Fibers and Polymers》2018,19(11):2359-2364
In this study, Berberis vulgaris L. wood as an agricultural waste was used for dyeing and functional finishing of cotton. To facilitate the attachment of natural dye, citric acid was used to create carboxylic acid functional groups on cotton fibers. The process of crosslinking of cotton fabric with citric acid was optimized in order to obtain the maximum dyeability with the cationic natural dye. The effects of three important factors including citric acid concentration, sodium hypophosphite concentration and curing temperature on the color strength of the dyed samples with woods of barberry tree were analyzed by response surface methodology and the optimum conditions for obtaining the highest color strength was obtained. The crosslinking of citric acid on cotton fibers was confirmed by FTIR spectroscopy. The dyed sample prepared under the optimum conditions of crosslinking showed good wash and light fastness properties besides very good antibacterial activity against gram-negative and gram-positive bacteria. 相似文献
108.
Perumal Palanivell Nik Muhamad Ab Majid 《Communications in Soil Science and Plant Analysis》2017,48(17):2083-2092
Application of urea in lowland rice fields leads to ammonia (NH3) volatilization and environmental pollution, and diminishes nitrogen recovery by rice (Oryza sativa L.). Amending urea with biochar could reduce NH3 loss from urea as well as improve chemical properties of acid soils. An incubation study was conducted using a closed-dynamic air flow system to determine NH3 volatilization from urea and chemical properties of an acid soil (Typic Paleudults). The soil was mixed with three rates of chicken litter biochar (20, 40, and 60 g pot?1) and 1.31 g urea. Mixing an acid soil with biochar (60 g pot?1) in waterlogged to stimulate conditions in paddy condition significantly reduced NH3 loss and total titratable acidity. Biochar application also increased soil pH, total nitrogen, available nitrate, organic matter, total organic carbon, total carbon, available phosphorus, and exchangeable cations. Thus, chicken litter biochar can be used to reduce urea-N loss and ameliorate chemical properties of acid soils. This aspect is being embarked on in our on-going field experiments. 相似文献
109.
Kobra Mahdavian Seyed Majid Ghaderian Masoud Torkzadeh-Mahani 《Journal of Soils and Sediments》2017,17(5):1310-1320
Purpose
This study investigated the extent of metal accumulation by plants colonizing a mining area in Yazd Province in Central Iran. It also investigated the suitability of these plants for phytoextraction and phytostabilization as two potential phytoremediation strategies.Materials and methods
Plants with a high bioconcentration factor (BCF) and low translocation factor (TF) have the potential for phytostabilization, whereas plants with both BCFs and TFs >1 may be appropriate for phytoextraction. In this study, both shoots and roots of 40 plant species and associated soil samples were collected and analyzed for total concentrations of trace elements (Pb, Zn, and Ag). BCFs and TFs were calculated for each element.Results and discussion
Nonnea persica, Achillea wilhelmsii, Erodium cicutarium, and Mentha longifolia were found to be the most suitable species for phytostabilization of Pb and Zn. Colchicum schimperi, Londesia eriantha, Lallemantia royleana, Bromus tectorum, Hordeum glaucum, and Thuspeinantha persica are the most promising species for element phytoextraction in sites slightly enriched by Ag. Ferula assa-foetida is the most suitable species for phytostabilization of the three studied metals. C. schimperi, L. eriantha, L. royleana, B. tectorum, M. longifolia, and T. persica accumulated Ag, albeit at low level.Conclusions
Our preliminary study shows that some native plant species growing on this contaminated site may have potential for phytoremediation.110.
Form of nitrogen present in soils is one of the factors that affect nitrogen loss. Nitrate is mobile in soils because it does not absorb on soil colloids, thus, causing it to be leached by rainfall to deeper soil layers or into the ground water. On the other hand, temporary retention and timely release of ammonium in soils regulate nitrogen availability for crops. In this study, composted paddy husk was used in studies of soil leaching, buffering capacity, and ammonium adsorption and desorption to determine the: (i) availability of exchangeable ammonium, available nitrate, and total nitrogen in an acid soil after leaching the soil for 30 days, (ii) soil buffering capacity, and (iii) ability of the composted paddy husk to adsorb and desorb ammonium from urea. Leaching of ammonium and nitrate were lower in all treatments with urea and composted paddy husk compared with urea alone. Higher retention of soil exchangeable ammonium, available nitrate, and total nitrogen of the soils with composted paddy husk were due to the high buffering capacity and cation exchange capacity of the amendment to adsorb ammonium thus, improving nitrogen availability through temporary retention on the exchange sites of the humic acids of the composted paddy husk. Nitrogen availability can be enhanced if urea is amended with composted paddy husk. 相似文献