Robust and scalable syntheses of some synthetically useful 3,5disubstituted phenols are presented. The process involves the selective displacement of a halogen by nucleophilic aromatic substitution using a preformed mixture of potassium tert-butoxide and p-methoxybenzyl alcohol (PMB-OH), followed by deprotection of the PMB ether with acid in the presence of 1,3-dimethoxybenzene. These processes have been demonstrated on kilogram scale, providing crystalline phenols in good yield and high purity.
A new technique is presented for designing actuators for guided hard-launch adaptive munitions by using actuator and substrate strain limits, static analysis methods and matching the local actuator strains along its length by varying the width. This Load-Matched design technique leads to an exponential area distribution as a function of length which is contrasted against the conventional rectangular actuator shapes that have been used in all adaptive hard-launch munitions up till now. To demonstrate the viability of this new Load-Matched actuator design, ten 600mg, 100mm long rectangular and ten identical mass and length, exponentially shaped, Load-Matched actuator specimens were designed and built to withstand the maximum possible accelerations. Predicted design static strain distributions are presented along with limits, showing that rectangular actuators exhibit a strong strain peak at the root while Load-Matched actuators have a much more even distribution and a gentle maximum near the middle. Shock table testing showed that the rectangular specimens were predicted to fail at 3,500g's, but survived acceleration levels 9.5 -12% higher than expected (3,833 to 3,93 ig's). The exponentially shaped Load-Matched actuators proved that they could withstand shocks from 17 to 21% over the predicted failure acceleration level of 8,000g's (9,377 to 9,670g's).
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