KAl(SO4)2.12H2O is found to efficiently and heterogeneously catalyze the one-pot three-component reaction of 2-(nitromethylene)imidazolidine, malononitrile and aldehydes under mild conditions to afford the corresponding tetrahydroimidazo[1,2-a]pyridine in good yields and short reaction times. Docking  study  of  some  compounds  in  the  active  site  of  α-glucosidase demonstrated  that  these...

A recently developed nonstationary stochastic model of strong earthquake ground motion is described. The model employs filtering of a white-noise process, where nonstationarity is achieved by modulating the intensity and varying the filter parameters in time. The model is fitted to a target accelerogram by matching a set of statistical measures that characterize the evolution of the intensity, ...

The turbulent fluctuations of velocity have been measured, using an electromagnetic flowmeter, at heights up to 1.75 meters above the sea bed. The area of observations was off Anglesey, North Wales, in depths of 12 to 22 meters, on a firm, sandy bottom and during neutrally stable conditions. A number of records of the longitudinal (u) and vertical (w) components of velocity were obtained, and a...

Abstract We reconstructed the past deep-water character of equatorial Indian Ocean using isotope ratio neodymium ( ε Nd ) in Fe–Mn coating mixed-species foraminifera. When compared with previous records at same site (ODP 758) and another to west (SK 129), three datasets were consistent showed glacial-interglacial variations, even though other two extracted from different media (cleaned foramini...

A simple procedure to identify site frequencies using earthquake response records from roofs and basements of buildings is presented. For this purpose, data from five different buildings are analyzed using only spectral analyses techniques. Additional data such as free-field records in close proximity to the buildings and site characterization data are also used to estimate site frequencies and...

Phosphosulfonic  acid  as a  multi  solid site  was  easily  prepared  from  the reaction of ammonium  dihydrogen phosphate with chlorosulfonic acid in CCl4and for improved  its  catalytic activity  was  supported  nano Silica was  extracted from  husk  rice  contains  about 95%  of  Silica the  size of  extracted nano silica was  determined  by  SEM  efficiency of  this solid acid in four comp...

In a sequence of random variables, record values are observations that exceed or fall below the current extreme value.Now consider a sequence of pairwise random variables  {(Xi,Yi), i>=1}, when the experimenter is interested in studying just thesequence of records of the first component, the second component associated with a record value of the first one is termed the concomitant of that ...

conclusions laparoscopic cholecystectomy as the method of choice in treatment of gallbladder stone is associated with high success rate. this approach is increasingly being performed because of the decrease in patients’ hospital stay, morbidity, and rapid return to normal life. patients and methods this is a retrospective study. medical records of patients who underwent laparoscopic cholecystec...