an efficient and eco-friendly protocol for the preparation of 2-amino-4h-chromenes employing a multi-component, one-pot condensation reaction between aromatic aldehydes, malononitrile and1-naphthol has been developed. the reaction of 1-naphthol with malononitrile and various aromatic aldehydes was carried out in water-ethanol (1:1) at reflux using 20 mol% of diammonium hydrogen phosphate as cat...

the extraction-separation of lanthanum and europium ions with bis(2-ethylhexyl) phosphoric acid (dehpa) in cyclohexane was improved by adding 12-crown-4 (12c4) to the aqueous phase as a masking agent. in the presence of this crown ether the extraction curve of lanthanum ions versus ph shifts to the higher ph region, while the curve is not influenced for the europium ions. consequently the separ...

l a r u t c u r t S h t l a e h g n i r o t i n o m H S ( M) h c e t i n qu s e h e v a t a r t i d i a n o l l y n e e b p p a li d e o t , l a c i n a h c e m , e c a p s o r e a d n a l i v i c s e r u t c u r t s o t n e d i t y f i o l g n i d a and a d m e g a a p ts n r e t . , r e v e w o H n a m u h s r o t a r e p o n i e h t p o o l n a y a l p t n a t r o p m i e l o r n i e h t l ...

C h r o m o p h o r e s o f C p h y c o c y a n i n a n d phycoerythrοc y a n i n h a v e b e e n c h e m i c a l l y m o d i f i e d by r e d u c t i o n t o r u b i n s , b l e a c h i n g , p h o t o i s o m e r i z a t i o n , o r p e r t u r b a t i o n w i t h b u l k y s u b s t i t u e n t s . P i g m e n t s c o n t a i n i n g m o d i f i e d c h r o m o p h o r e s , o r h y b r i d ...

sexual behavior in most moths is limited to a precise duration period of either the day or the night. these behaviors as well as the calling behavior are specific. information on reproductive behavior is important in the chemical ecology studies. experiments were conducted to determine the developmental biology, adult time emergence and calling behaviors of three populations of carob moth, ecto...

EXAFS s t u d i e s w i t h h i g h s p a t i a l r e s o l u t i o n h a v e been per formed a t t h e Se K-edge e d g e o f SmSe a t 7 7 K a n d up t o 57kbar. An i n c r e a s e i n t h e f l u c t u a t i o n o f t h e Sm-Se bond l e n g t h o f -0.05 A is o b s e r v e d upon g o i n g t h r o u g h t h e i s o s t r u c t u r a l mixed v a l e n t t r a n s i t i o n which is c o n t i n ...

t h e m s e l v e s i n t h e p e r s p e c t i v e o f r e s e a r c h o n t h e o r i g i n s o f s p e e c h , a n d d o n o t a s k t h e q u e s t i o n w h e r e t h e s o u n d s y s t e m t h e y a s s u m e c o m e s f r o m . T o i l l u s t r a t e t h i s p r o c e s s , I w i l l r e d o s o m e s i m u l a t i o n s s i m i l a r t o t h o s e p r e s e n t e d e a r l i e r , b u...

This p a p e r descr ibes 4 s i m p l e t r ee p a t t e r n m a t c h i n g a l g o r i t h m f o r t h e code g e n e r a t o r of compi l e r s . T h e i n t e r m e d i a t e code ( R e g i s t e r T r a n s f e r L a n g u a g e ) is m a t c h e d with t h e tree-rewri t ing ru le s of t h e i n s t r u c t i o n d e s c r i p t i o n w h i c h describe t h e t a r g e t archi tecture t o ...

the chemical composition of the essential oil of fruits of pimpinella haussknechtiiboiss.was studied by gc-ms. after gc-ms analysis, one unknown component (56.7%) was observed, which was not characterized in the gc-ms library. the essential oil of p.hauskenekhtii was injected to hplc using ymc-pak-sil column (250 × 20 mm) with gradient system of hexane (a), and hexane: ethyl acetate, 9:1 (b) to...

the aim of this research was to survey of using soy protein isolates and tragacanth gum as egg substitutes in mayonnaise formulation. the mayonnaise prepared with difierent compositions of soy protein isolate, egg, and tragacanth by applying the optimal mixture design method and effect of this substitution on its stability, heat stability, viscosity, texture, physicochemical and sensory charact...