Mars global surveyor navigation and aerobraking at Mars

The Mars Global Surveyor (MGS) spacecraft was successfully inserted into an elliptical orbit around Mars on 9/12/97, 01:53:49 UTC. This orbit was near polar (inclination = 93.26 deg) with an orbital period of 44.993 hours and apoapsis and periapsis altitudes of 54,025.9 km and 262.9 km respectively. After a short aerobraking (AB) initiation interval (9/12/97 to 10/2/97), the main phase of AB or orbit period reduction was established. However shortly thereafter, a significant problem with the minus-Y axis solar array developed which necessitated a temporary suspension of AB. Ultimately, this forced the Project to abandon the original plan to complete AB on 1/18/98 and establish the mapping orbit on 3/15/98. The revised plan called for a reduced level of AB, thus subjecting the solar array and yoke assembly to less aerodynamic stress. After 201 orbits and 196 days after MOI, the first phase of AB has ended, the orbital period was 11.64 hours with apoapsis and periapsis altitudes of 17,870.3 and 170.7 km respectively. At present, MGS is in a science phasing orbit (SPO) and shall acquire science data from 3/28/98 to 9/11/98. Thereafter the second phase of AB shall begin and is expected to end during Feb 1999 when the orbital period shall be 1.9 hours and the orbit's descending node shall be at the 2:00 am (local mean solar time) orientation

Generation and Characterization of an scFv Directed against Site II of Rabies Glycoprotein

Recombinant antibody phage display technology is a vital tool that facilitates identification of specific binding molecules to a target enabling the rapid generation and selection of high affinity, fully human, or mouse antibody product candidates essentially directed towards disease target appropriate for antibody therapy. In this study, a recombinant single-chain Fv antibody fragment (scFv) A11 was isolated from immune spleen cells obtained from mice immunized with inactivated rabies virus (Pasteur strain) using standard methodology and was characterized for its specificity towards the rabies virus glycoprotein. Epitope mapping using peptide libraries and truncated glycoprotein polypeptides suggested that A11 bound to the antigenic site II of rabies glycoprotein against which a majority of rabies virus neutralizing antibodies are directed. The use of the above technology could, therefore, allow development of scFvs with different specificities against the rabies glycoprotein as an alternative to the more cumbersome protocols used for the development of monoclonal antibodies

Stress analysis of a tube mill

The tube mill is essentially a piece of grinding equipment used in the chemical industries to achieve reduction of particle size. In this article a mill of this type has been analysed for static loading by use of the classical thin-shell theories of Donnell, Sanders, Novozhilov, and Flügge and the results have been compared with each other. Experimental work has been carried out to check the theoretical results and also to determine the effect of dynamic loads. It is observed that for the peripheral velocities encountered in the normal operation of a tube mill the dynamic effects are not very pronounced. Hence the design of a tube mill based on static analysis is quite adequate

Comparison of elasticity theory and shell theory solutions

The axisymmetric bending of cylinder-cone shell junction has been analysed by the finite element method using three dimensional elasticity theory. Numerical results have been worked out for three shells having cylinder diameter to thickness ratios of 41, 21 and 13. These results have been compared with the results obtained by the classical thin shell theory of Sanders. The validity of the assumptions made in the classical thin shell theory is discussed. The nature of singularity at the re-entrant corner has been studied

Kinetics of General & Specific Catalysis During Hydrolysis of 1-Benzoylbenzotriazoles

564-56

Metal Ion Promoted Hydrolysis of p-Nitrophenyl Anthranilates, Glutarate, Salicylate, ɑ-Thiophenate & ɑ-Furoate

476-48