A modified linear membrane theory for the pressurized toroid
Pressurized toroid modified linear membrane theory, presenting approximate solutions for derived boundary value problem by variational calculus methods
Clark, S. K.↗
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Interaction of a compressible fluid and an elastic membrane
Unsteady interaction of compressible fluid and flat circular deforming elastic membrane analyzed coupled computer program method
Madden, R.↗
Stabilization of porous glass hyperfiltration membranes by aluminium chloride solution
Porous glass hyperfiltration membranes stabilization by aluminum chloride solution, noting retreatment need
Ballou, E. V.↗
An electrostatic computer model of a biological membrane
Computerized electrostatic field model of biological cell membrane
Gallucci, V. F.↗
Stabilization of porous glass reverse-osmosis membranes
Application of porous glass in form of capillary tubes for low capacity ion exchange in hyperfiltration experiments is discussed. Efficiency of desalination by process of reverse osmosis is described. Stabilization of porous glass membrane by presence of aluminum chloride is analyzed.
Ballou, E. V.↗
Rapid evaluation of reverse-osmosis membranes
Simultaneous reverse-osmosis tests conducted with centrifuges having multiple compartment heads are discussed. Equipment for retaining reverse-osmosis membrane is illustrated. Method of conducting tests is described.
Hollahan, J. R.↗
Reverse-osmosis membranes by plasma polymerization
Thin allyl amine polymer films were developed using plasma polymerization. Resulting dry composite membranes effectively reject sodium chloride during reverse osmosis. Films are 98% sodium chloride rejective, and 46% urea rejective.
Hollahan, J. R.↗
An isoparametric quadrilateral membrane element for NASTRAN
The geometric and kinematic properties of the element are described, along with development of the matrices and vectors which characterize the element. The necessity for considering small deviations from element planeness is discussed, and the approach taken to account for these deviations is described. The improved accuracy over the existing quadrilateral membrane is indicated by a sample calculation for which an analytical solution is available from beam theory. For the same finite element idealization, the errors in maximum displacement and stress were significantly reduced.
Adelman, H. M.↗
Origin and development of plasma membrane derived invaginations in Vinca rosea l.
The occurrence, morphology, and possible ontogeny of plasma-membrane-related structures are described which can develop into invaginations or intravacuolar formations. An underlying study of meristematic tissues from the shoot of Vinca rosea supports the interpretation that endocytosis does occur in plant cells and that it is appropriate to refer to these structures as endocytoses. The function of these invaginations or their content remains to be elucidated.
Mahlberg, P.↗
Membrane evaporator/sublimator investigation
Data are presented on a new evaporator/sublimator concept using a hollow fiber membrane unit with a high permeability to liquid water. The aim of the program was to obtain a more reliable, lightweight and simpler Extra Vehicular Life Support System (EVLSS) cooling concept than is currently being used.
Elam, J.↗
Membrane humidity control investigation
The basic performance data on a hollow fiber membrane unit that removes water from a breathing gas loop by diffusion is presented. Using available permeability data for cellulose acetate, a preliminary design was made of a dehumidifier unit that would meet the problem statement.
Elam, J.↗
Evaluation of membrane filter field monitors for microbiological air sampling
Due to area constraints encountered in assembly and testing areas of spacecraft, the membrane filter field monitor (MF) and the National Aeronautics and Space Administration-accepted Reyniers slit air sampler were compared for recovery of airborne microbial contamination. The intramural air in a microbiological laboratory area and a clean room environment used for the assembly and testing of the Apollo spacecraft was studied. A significantly higher number of microorganisms was recovered by the Reyniers sampler. A high degree of consistency between the two sampling methods was shown by a regression analysis, with a correlation coefficient of 0.93. The MF samplers detected 79% of the concentration measured by the Reyniers slit samplers. The types of microorganisms identified from both sampling methods were similar.
Fields, N. D.↗
Improved ion exchange membrane
Membrane, made from commercially-available hollow fibers, is used in reverse osmosis, or dialysis. Fiber has skin layers which pass only small molecules. Macromolecules cannot penetrate skin. Fibers can also be used to remove other undesirable anions, such as phosphate, sulfate, carbonate, and uranium in form of uranium-sulfate complex.
Rembaum, A.↗
Method of preparing water purification membranes
Allyl amine and chemically related compounds are polymerized as thin films in the presence of a plasma discharge. The monomer compound can be polymerized by itself or in the presence of an additive gas to promote polymerization and act as a carrier. The polymerized films thus produced show outstanding advantages when used as reverse osmosis membranes.
Hollahan, J. R.↗
Parametric test of a zirconium (4) oxide-polyacrylic acid dual layer hyperfiltration membrane with spacecraft washwater
Performance data consisting of solute rejections and product flux were measured, as dependent on the operation parameters. These parameters and ranges were pressure (500,000 n/m2 to 700,000 n/m2), temperature (74 C to 95 C), velocity (1.6 M/sec to 10 M/sec), and concentration (up to 14x). Tests were carried out on analog washwater. Data presented include rejections of organic materials, ammonia, urea, and an assortment of ions. The membrane used was deposited in situ on a porcelain ceramic substrate.
Brandon, C. A.↗
Parametric evaluation of a dual-layer dynamic hyperfiltration membrane for recovery of spacecraft wash water at elevated temperature
Performance data consisting of solute rejections and product flux have been measured, as dependent on the operational parameters. These parameters were pressure, 5,000,000 N/sq m (750 psia) to 7,000,000 N/sq m (1040 psia); temperature, 347 K (165 F) to 368 K (200 F); velocity, 1.6 m/s to 10 m/s; and concentration (up to 14x). Tests were carried out on analog wash water. Data taken include rejections of organic materials (TOC), ammonia, urea, and an assortment of ions. The membrane used was a dual-layer, polyacrylic acid over zirconium oxide, deposited in situ on a porcelain ceramic substrate.
Brandon, C. A.↗
Investigations of the inhibitory effects of tocopherol (vitamin E) on free radical deterioration of cellular membranes
The inhibitory effects are investigated of d,1-alpha-tocopherol and d,1-alpha-tocopheryl acetate on the free radical deterioration of cellular membranes. The level of toxicity of d,1-alpha-tocopherol and d,1-alpha-tocopheryl acetate in mice is determined.
Richardson, D.↗
Large deflections of shallow conical membrane
Large deflections of a shallow elastic conical membrane fixed at the outer edge and loaded by either uniform or hydrostatic pressure are investigated. The overning equations were solved by the method of matched asymptotic expansions and by a finite difference method. Agreement between the two methods was excellent for the small values of the perturbation parameter.
Chang, W. H.↗