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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

High Performance (R-10/inch) Clay-Cellulose-Silica Nanopore Insulation Board For New and Retrofit Buildings (Final Scientific Report)

The objective of Liatris’s 3-year DOE BENEFIT project was to develop and validate a high-performance, lightweight, aerogel-based insulation board of ≥R-10/inch at a cost of ≤$\$$1.50 per board foot using non-flammable inorganic nanocomposites. We have summarized each yearly goal below: Year 1 – Ambient dried inorganic/organic nanocomposite, R-6/inch Year 2 – Processing efficiency and cost down, R-8/inch at $\$$2.0/board-ft Year 3 – Scale up to continuous, pilot production of R-10 at ≤ $\$$1.50/board-ft Over the course of the project period, Liatris has successfully met or exceeded all of the goals outlined above. The project scope over 3 years was extensive, covering method development of ambient dried silica aerogels in Budget Period 1, process formulation and R-value improvement in Budget Period 2, and composite scale up with corporate partners in Budget Period 3. Over the course of the project Liatris has been able to progressively improve the thermal resistance properties from about R-6/in to > R-11/in, 2-3X the performance of conventional insulation products.

36 MATERIALS SCIENCE↗
NASA NTRS1979

The role of metal ions in chemical evolution - Polymerization of alanine and glycine in a cation-exchanged clay environment

The effect of the exchangeable cation on the condensation of glycine and alanine was investigated using a series of homoionic bentonites. A cycling procedure of drying, warming and wetting was employed. Peptide bond formation was observed, and the effectiveness of metal ions to catalyze the condensation was Cu(2+) greater than Ni(2) approximately equals Zn(2+) greater than Na(+). Glycine showed 6% of the monomer incorporated into oligomers with the largest detected being the pentamer. Alanine showed less peptide bond formation (a maximum of 2%) and only the dimer was observed.

Lawless, J. G.↗
NASA NTRS1982

Initial energy partitioning and some excavation stage phenomenology in laboratory-scale cratering calculations in clay

One impact and two explosive cratering calculations have been analyzed with emphasis on the early excavation stage. The early excavation stage is here defined as that part of the excavation stage that occurs after energy partitioning is 90% complete, but before the cratering flow field can be well described by Z-type flow fields with values of Z uniformly greater than two. Impact generated flow fields seem to have a much longer early excavation stage than explosion generated flow fields, due possibly to the slower momentum transfer versus energy transfer rate between projectile and target. During this time when the projectile retains a significant portion of its original momentum, Z values less than two are observed in the impact generated flow field. Z values less than two are not observed at any time in the explosion generated flow fields.

Austin, M. G.↗
NASA NTRS1982

Prolonged triboluminescence in clays and other minerals

The decay curves of various triboluminescent-excited materials were obtained, including well-crystallized and poorly crystallized kaolin, bentonite, quartz, sodium chloride, and chalk calcite. A qualitative increase in triboluminescence was observed for kaolin dipped in water or tryptophan solution compared to dry kaolin, and for frozen kaolin and montmorillonite pastes. Theoretical explanations for the tryptophan effect are discussed.

Lahav, N.↗
NASA NTRS1984

Deflocculation of clay suspensions using sodium polyacrylates

Rheological properties of elutriated kaolin suspensions deflocculated by Na polyacrylate (DAC 3 and DAC 4) were studied and compared to those deflocculated by the conventional Na2CO3 water and glass and imported Dispex N40. The deflocculating effect of Na polyacrylate was comparable to that of Dispex N40. The optimum amounts of Na polyacrylate were determined for suspensions based on 5-type kaolin. The Na polyacrylate can be successfully used for decreasing the water content of ceramic slips for casting and spray drying.

Jedlicka, P.↗
NASA NTRS1985

Properties of Filamentary Sublimation Residues from Dispersions of Clay in Ice

The properties of sublimate residues are of considerable interest in studies of the thermal modeling of Martian and cometary ice surfaces. The study of the formation of sand grains from this mantle on Martian polar ice is also supported by these experiments. To understand these properties, a series of low temperature vacuum experiments were run during which dirty ices that might be expected to be found in Martian polar caps and in comet nuclei were made and then freeze dried. In addition to using particulate material of appropriate grain size and minerology, particle nucleated ices were simulated by dispersing the particulates in the ice so that they did not contact one another. This noncontact dispersion was the most difficult requirement to achieve but the most rewarding in that it produced a new filamentary sublimate residue that was not a relic of the frozen dispersion. If the siliceous particles are allowed to touch one another in the ice the structure of the contacting particles in the ice will remain as a relic after the ice is sublimed away.

Stephens, J. B.↗
NASA NTRS1985

Structure of the Melajo clay near Arima, Trinidad and strike-slip motion in the El Pilar fault zone

No consensus has yet emerged on the sense, timing and amount of motion in the El Pilar fault zone. As a contribution to the study of this problem, a critical area within the zone in North Central Trinidad has been mapped. On the basis of the mapping, it is concluded that the El Pilar zone has been active in right-lateral strike-slip motion during the Pleistocene. Recognition of structural styles akin to those of the mapped area leads to the suggestion that the El Pilar zone is part of a 300 km wide plate boundary zone extending from the Orinoco delta northward to Grenada. Lateral motion of the Caribbean plate with respect to South America has been suggested to amount to 1900 km in the last 38 Ma. Part of this displacement since the Miocene can be readily accommodated within the broad zone identified here. No one fault system need account for more than a fraction of the total motion and all faults need not be active simultaneously.

Robertson, P.↗
NASA NTRS1988

Marine and continental K-T boundary clays compared

Detailed geochemical and mineralogical studies (1 to 5) of sediments across the Cretaceous-Tertiary (K-T) boundary at Stevns Klint, Karlstrup, Nye Klov, Dania, and Kjolby Gaard in Denmark, at Limhamn in Sweden, at Caravaca in Spain, at Waipara and Woodside Creek in New Zealand, at Trinidad in Colorado, and at various sites in Montana, have induced conclusions and reflections which are given and briefly discussed.

Schmitz, B.↗
NASA NTRS1989

Oligomerization reactions of deoxyribonucleotides on montmorillonite clay - The effect of mononucleotide structure on phosphodiester bond formation

The formation of oligomers from deoxynucleotides, catalyzed by Na(+)-montmorillonite, was investigated with special attention given to the effect of the monomer structure on the phosphodiester bond formation. It was found that adenine deoxynucleotides bind more strongly to montmorillonite than do the corresponding ribonucleotides and thymidine nucleotides. Tetramers of 2-prime-dpA were detected in the reaction of 2-prime-d-5-prime-AMP with a water-soluble carbodiimide EDAC in the presence of Na(+)-montmorillonite, illustrating the possible role of minerals in the formation of biopolymers on the primitive earth.

Ferris, James P.↗
NASA NTRS1990

Oligomerization reactions of deoxyribonucleotides on montmorillonite clay - The effect of mononucleotide structure, phosphate activation and montmorillonite composition on phosphodiester bond formation

The 2(prime)-d-5(prime)-GMP and 2(prime)-d-5(prime)-AMP bind 2 times more strongly to montmorillonite 22A than do 2(prime)-d-5(prime)-CMP and 5(prime)-TMP. The dinucleotide d(pG)2 forms in 9.2 percent yield and the cyclic dinucleotide c(dpG)2 in 5.4 percent yield in the reaction of 2(prime)-d-5(prime)-GMP with EDAC in the presence of montmorillonite 22A. The yield of dimers which contain the phosphodiester bond decreases as the reaction medium is changed from 0.2 M NaCl to a mixture of 0.2 M NaCl and 0.075 M MgCl2. A low yield of d(pA)2 was observed in the condensation reaction of 5(prime)-ImdpA on montmorillonite 22A. The yield of d(pA)2 obtained when EDAC is used as the condensing agent increases with increasing iron content of the Na(+)-montmorillonite used as catalyst. Evidence is presented which shows that the acidity of the Na(+)-montmorillonite is a necessary but not sufficient factor for the montmorillonite catalysis of phosphodiester bond formation.

Ferris, James P.↗
NASA NTRS1991

Clay minerals in primitive meteorites and interplanetary dust 2. Smectites and micas

The classification is briefly summarized of stony meteorites and cosmic dust, and the mineralogy and chemistry is described of serpentine group minerals. The occurrence of smectites and micas in extraterrestrial materials is examined. The characterization of fine grained minerals in meteorites and IDPs relies heavily on electron beam instruments, especially the transmission electron microscope (TEM). Typically, phyllosilicates are identified by a combination of high resolution imaging of basal spacings, electron diffraction, and chemical analysis. Smectites can be difficult to differentiate from micas because the smectites lose their interlayer water and the interlayer partly collapse in the high vacuum of the TEM.

Keller, L. P.↗
NASA NTRS1991

Clay minerals in primitive meteorites and interplanetary dust 1

Many meteorites and interplanetary dust particles (IDPs) with primitive compositions contain significant amounts of phyllosilicate minerals, which are generally interpreted as evidence of protoplanetary aqueous alteration at an early period of the solar system. These meteorites are chondrites (near solar composition) of the carbonaceous and ordinary varieties. The former are subdivided (according to bulk composition and petrology) into CI, CM, CV, CO, CR, and ungrouped classes. IDPs are extraterrestrial particulates, collected in stratosphere, which have chemical compositions indicative of a primitive origin; they are typically distinct from the primitive meteorites. Characterization of phyllosilicates in these materials is a high priority because of the important physico-chemical information they hold. The most common phyllosilicates present in chondritic extraterrestrial materials are serpentine-group minerals, smectites, and micas. We discuss these phyllosilicates and describe the interpretation of their occurrence in meteorites and IDPs and what this indicates about history of their parent bodies, which are probably the hydrous asteroids.

Zolensky, M. E.↗