to compensate for some inferior properties of recycled papers, application of processing chemical aids such as chitosan can be quite effective in the wet end section of papermaking. in this study, the performance of chitosan biopolymer, individually or associated with nanobentonite was investigated as wet end additive on recycling process of white cuttings. for this purpose, the performance of ...

the district of miyān kūh in the ardal town,chahār mahāl bakhtiari province, because of its high mountains, deep valleys and the fields among small mounts, being placed in the path of the was dering tribes has been the focus of the attention. the rigion has two different viewpoint. one part featuring the mounts chēhēl cheshme and gereh with the altitude of more than 3500 m., has cold winter and...

to determine sugar content and root yield variation of new sugar beet hybrids under different irrigation levels, an experiment was carried out at zarghan agricultural research station offars agricultural and natural resources research center, shiraz, iran. the study was conducted as split block based on a randomized complete block design with three replications for two years, 2009-10, using lin...

this study presents an empirical relationship of suspended sediment concentrations (sscs) inthe coastal waters, which is derived from the conventional methods, to radiometer remote sensing reflectance values (rrs) and satellite data in coastal waters of kerala. an algorithm is then developed to utilize both in situ sscs measured from conventional methods and rrs values. this algorithm is valida...

P h y t o p l a n k t o n c o m p o s i t i o n a n d t h e r a n g e o f s e a s o n a l p a t t e r n s o f a b u n d a n c e a r e p r e s e n t e d f o r t h e t i d a l f r e s h w a t e r r e g i o n s i n t w o V i r g i n i a r i v e r s b a s e d o n d a t a a c c u m u l a t e d m o n t h l y f r o m 1 9 8 6 t h r o u g h 1 9 9 9 . D i a t o m s d o m i n a t e d t h e f l o r a d u r...

f o r m e d t h e o p e r a t i o n a l f o u n d a t i o n s o f s c i e n c e , t h a t w e r e l a r g e l y t h e h e r i t a g e f r o m t h e t i m e o f A r i s t o t l e , i n t o i t s m o d e r n f o r m . T h e s e n e w f o u n d a t i o n s c o n s i s t e d o f t h e u s e o f ( 1 ) P h y s i c a l E x p e r i m e n t s a n d t h e u s e o f ( 2 ) M a t h e m a t i c a l M o d e l...

introduction there are significant differences in the spatial distribution of the iran annual precipitation. this is resulted from spatial behavior of precipitation in the one hand and variation in the sources of precipitation on the other. the lack of adequate distribution of meteorological stations and the unavailability of long-term statistics of precipitation makes the analysis of precipita...

deficiency of water resources is one of the major challenges at the global scale and also in iran. the existence water resources of oceans and seas such as the caspian sea and persian gulf in the north and southern parts of iran respectively, can be considered as the alternative to dominate the future problem. this study is processed absorption of nacl based-on natural zeolite and perlite. in o...

earthworms are an important part of food chain in soil ecosystem. in polluted soils, heavy metals are consumed by earthworms and transferred to other organisms through food chain, resulting in many adverse health impacts. due to the benefits of earthworms for soil fertility, it is important to assess the effects of soil pollution on population, biomass and functions of earthworms. to determine ...

"̂T^ H A T P O T E N T I A L F O R T E 1 E E N R I C H M E N T O F I s c i e n c e is w h a t B a r r o w h a s se t o u t t o e x p l o r e _JL i n Impossibility. A p r o f e s s o r o f a s t r o n o m y a t t h e U n i v e r s i t y o f S u s s e x i n E n g l a n d , B a r r o w w r i t e s w i t h g r e a t s c h o l a r s h i p , e l e g a n c e a n d w i t . H e classif ies t h e l i m i ...