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Digital stiffness programmability is fulfilled with a heterogeneous mechanical metamaterial. The prototype consists of an elastomer matrix containing tessellations of diamond shaped cavities selectively confined with semi-rigid plastic beam inserts along their diagonals. Unit-cell perturbations by placing or removing each insert reshape the global constitutive relation whose lower and upper bounds corresponding to the configurations with all holes empty and all inserts in place, respectively, are significantly distant from each other thanks to a gap between the moduli of the elastomer and the inserts. Bidirectional operation is achieved by mixing insert orientations where longitudinal inserts enhance the macroscopic stiffness in compression and transverse ones tension. Arranged digital representations of such local insert states form the explicit encoding of global patterns so that systematic stiffness programming with minimal changes in mass is enabled both statically and in situ. These characteristics establish a new paradigm in actively tuning vibration isolation systems according to shifts in the resonance of base structures.

Experiments were performed in which meteoritic iron, iron ore and nickel-iron alloy were used to catalyze (in Fischer-Tropsch synthesis) the reaction of deuterium and carbon monoxide in a closed vessel. Normal alkanes and alkenes and their monomethyl substituted isomers and aromatic hydrocarbons were synthesized. Iron oxide and oxidized-reduced Canyon Diablo used as Fischer-Tropsch catalysts were found to produce aromatic hydrocarbons in distributions having many of the features of those observed in carbonaceous chondrites, but only at temperatures and reaction times well above 300 C and 6-8 h.

DCl was used to distinguish hydrocarbons produced by acid treatment from hydrocarbons originally present in the samples when volatiles released by acid and thermal treatments from Apollo 11, 12, and 14 lunar samples were studied by quadrupole mass spectrometry and gas chromatography mass spectrometry. Multiple ion plotting permitted separation of deuterated from nondeuterated hydrocarbons in the DCl products. Stepwise thermal treatment was used to distinguish the source of the volatile compounds. The presence of LM rocket exhaust products was traced in two samples, and the presence of high-temperature stable nitrides in some samples is indicated.

Type III carbonaceous chondrite Murchison meteorite, obtaining amino acids, aliphatic and aromatic hydrocarbons from specimen

Organogenic elements and compounds abundances and distribution in Apollo 12 fines

Apollo 11 and 12 lunar soil samples common contaminant identified as diisopropyl disulfide, using chromatograph mass spectrometer

Lunar carbonaceous, organic and organogenic materials analysis by mass spectroscopy, gas chromatography and various other methods