A process for fabricating an X-ray spectrometer having imaging and energy resolution of X-ray sources. The spectrometer has an array of adjoining rectangularly shaped detector cells formed in a silicon body. The walls of the cells are created by laser drilling holes completely through the silicon body and diffusing n+ phosphorous doping material therethrough. A thermally migrated aluminum electrode is formed centrally through each of the cells. A dual two-beam differential interferometer that measures both the amplitude and orientation of propagating, broadband surface acoustic waves. Four beams are focused on a surface. The four reflected beams are separated into two pairs. The two pairs are detected to produce two signals that are used to compute amplitude and orientation. Novel polyphenylene ethers with imide linking units are disclosed. These polymers incorporate the solvent and thermal resistance of polyimides and the processability of polyphenylene ethers. Improved physical properties over those of the prior art are obtained by incorporating meta linked ethers and/or polyphenylene oxides into the polymer backbone. A novel process for making polymers of this type is also disclosed. The process is unique in that the expected need of high process temperatures and/or special atmospheres are eliminated. ZERO TORQUE GEAR HEAD WRENCH NASA Case No. NPO-13059 Inventor: Allan R. McDougal, et al. Address inquiries to: NASA Resident Legal Office Corresponding to U.S. Patent No. 3,942,298 Filed 10-10-74 Issued 3-9-76 Difficulties are often encountered in spacecraft assembly operations because of the existence of torsional stresses induced as a consequence of the tightening of certain bolts employed during such assembly operations. The present invention is a gear head wrench. for applying torque to bolts without transferring torsional stresses to bolt-receiving structures. The wrench has an outer housing adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. ION BEAM SPUTTER-ETCHED VENTRICULAR This invention is directed to an improved cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure. The invention is further concerned with an improved method of shunting the cerebral fluid from the cerebral ventricles to other areas of the body. 14 18 10 12 16 |