A rapid and chemoselective method for the N-formylation of structurally diverse anilines with formic acid using nanoalumina sulfonic acid (NASA) at 70oC under solvent-free condition has been developed. The catalyst was found to be compatible with different functional groups and the formylation proceeded smoothly with anilines bearing electron withdrawing as well as electron donating substituents.

background: creating a socket with proper fit is an important factor to ensure the comfort and control of prosthetic devices. several techniques are commonly used to cast transtibial stumps but their effect on stump shape deformation is not well understood. this study compares the dimensions, circumferences and volumes of the positive casts and also the socket comfort between two casting method...

An apparatus to simulate the thermal behavior of a 3/4 inch bore tapered roller bearing was constructed and used to determine tapered roller bearing thermal behavior. Bearing specimens can be loaded axially and/or radially while rotating. Shaft heating is also provided and mechanical losses measured. An infrared scanner and thermocouples allow for temperature measurement. An analytical model of...

In recent years, determining bearing capacity of piles from in-situ testing data as a complement to static and dynamic analysis has been used by geotechnical engineers. In this paper, different approaches for estimating bearing capacity of piles from SPT data are studied and compared. A new method based on N value from SPT is presented. Data averaging, &#10failure zone and plunging failure of p...

Crack fault of rotor is one of the most prominent problems faced by magnetic bearing rotor system. In order to improve the safety performance of this kind of machinery, it is necessary to research the vibration characteristics of magnetic bearing cracked rotor system. In this paper, the stiffness model of the crack shaft element was established by the strain energy release rate (SERR) theory. T...

use of auxiliary elements in refining and betterment of engineering properties of soil have gained attention since a long time ago. nowadays the effectiveness and capability of the soil reinforcing technique for giving proper practical solutions in various projects have resulted in this technique quickly gaining a place in geotechnical engineering. in this paper, the results of laboratory studi...