sizing of paperboard has a distinctive position in packaging grade paperboard material. optimization of sizing by alum-rosin at neutral ph in 4 layered paperboard (330 g/m2) wereevaluated in this study to find the optimum ratio of alum- rosin loading in the process. fixed amount of 1% cationic dispersed rosin together with alum as a fixing agent at 5 different levels of 1, 1.5, 2, 3, and 4% (ba...

background and purpose: learning style is the processing of information and comprehension. if teachers present contents in a style that matches a student’s preferred learning style, academic performance and success will improve. if content retention improves it will result in an increase in the test scores. it is also important to determine if students, as a group, fit into a particular style o...

1920x1200 abstract: background: down syndrome is the most common chromosomal abnormality due to 21 trisomy that usually is accompany with congenital heart diseases. about fifty present of children with down syndrome have heart defects. this study was designed for the aim of abundance percents of septal heart defects in children with down syndrome at imam reza and imam ali hospitals in kermansha...

the adequacy of the swat model in the estimation of runoff, sediment yield and nitrate loss in the gorganrood watershed was tested, using the existing spatial database as the primary data. the model was then executed for a 31-years’ time period. in combination with the swat model, the sequential uncertainty fitting program (swat-cup and sufi-2) was added used to calibrate and validate a hydrolo...

the effect of arbuscular mycorrhizal fungi and plant growth promoting rhizobacteria, with the ability to produce acc deaminase enzyme, on water relationships and agronomic indices of sunflower (helianthus annuus l.) cultivars was investigated. the soil used was of an ec equal to 7.6 ds m-1. a greenhouse factorial experiment on the basis of a completely randomized block design with three levels ...

evaluation of changes present in soil and water resources due to operation implement of floodwater spreading is necessary to assess their positive or negative resultant effect. rate of the internal sediment to diversion spreader channels, surface sedimentation and aggregation of the spreading field depth are most important effective attributes on the yield of floodwater spreading systems. these...

in order to determine the practical method to predict economic production of wheat in competition with feral rye by using regression models, a factorial experiment was carried out based on randomized complete block design with three replications in dargaz. iran. experimental factors were included wheat cultivars (sayson, alvand, chamran and sepahan) and feral rye densities (0, 20, 40, 60 and 80...

drought stress as the most important abiotic stress plays a significant role in reduction of crops yield. this study was conducted at six agricultural experimental stations (karadj, ardebil, arak, mashhad, jolgerokh and miandoab) during 2006-08 cropping seasons. experiments were carried out under normal irrigation and post-anthesis drought stress conditions using 18 wheat genotypes. experimenta...