This article discusses the advantages and the process technique of lost foam casting. It describes the pattern molding for the lost foam process that is grouped into four major functions: filling, fusion, cooling stabilization , and ejection.
The article provides information on the application of the pattern coating. It concludes with a review of the quality of the lost foam casting in terms of dimensional tolerances, fold defects, and porosity.
Sign In or Create an Account. User Tools. Sign In. Skip Nav Destination Close mobile search navigation. ASM Handbook. Edited by. Mercury Marine. This Site. Google Scholar. John Weritz ; John Weritz. Aluminum Association. Kaufman Associates. The composite is formed by mixing the particulate with pitch prior to foaming. The effect of heating temperature and stirring time during preparation of foam aluminum alloy A on its relative porosity is studied.
The optimum amount of the foam -forming agent, i. Optimum conditions are established for foam formation in a melt during stirring using a mixer are described. It was found that these foams are capable of encapsulation of a desired volume, though the ideal and experimental expansion coefficients were found to differ.
Both were found to return to room temperature after 20 minutes regardless of the volume of foam cast. Fire retardant polyisocyanurate foam. Fire retardant properties of low density polymer foam are increased. Foam has pendant nitrile groups which form thermally-stable heterocyclic structures at temperature below degradation temperature of urethane linkages. Polyurethane- Foam Maskant. Brown wax previously used to mask hardware replaced with polyurethane foam in electroplating and electroforming operations.
Foam easier to apply and remove than wax and does not contaminate electrolytes. Prototype Salvage Foaming System. In the full-scale machine, the head flushing chemical is This type of hose is also much more resistant to kinking than. Lost Hills Subsidence Animation. This frame from an animation depicts ground subsidence resulting from the extraction of oil. The oil fields are located near the community of Lost Hills, California, approximately km northwest of Bakersfield.
Viscoelastic foam cushion. Foam is viscous and elastic with unusual and useful temperature, humidity, and compression responses. Applied weight and pressure distributed equally along entire interface with foam eliminates any pressure points.
Flexible urethane foam is ideal for orthopedic and prosthetic devices, sports equipment, furniture, and crash protection. Metallized polymeric foam material. Open-celled polyurethane foams can be coated uniformly with thin film of metal by vapor deposition of aluminum or by sensitization of foam followed by electroless deposition of nickel or copper.
Foam can be further processed to increase thickness of metal overcoat to impart rigidity or to provide inert surface with only modest increase in weight. Shooting in a foam. We study the motion of a solid sphere after its fast impact on a bath of liquid foam. We identify two regimes of deceleration.
At short times, the velocity is still large and the foam behaves similar to a Newtonian fluid of constant viscosity. Then we measure a velocity threshold below which the sphere starts experiencing the foam 's elasticity. We interpret this behavior using a visco-elasto-plastic model for foam rheology. Finally we discuss the possibility of stopping a projectile in the foam , and evaluate the capture efficiency.
Paper Casting. Describes an art project, based on the work of artist Chew Teng Beng, in the molding of wet paper on a plaster cast to create embossed paper designs. The values of such a project are outlined, including a note that its tactile approach makes it suitable to visually handicapped students. A device is described for casting uranium which comprises a crucible, a rotatable table holding a plurality of molds, and a shell around both the crucible and the table.
The bottom of the crucible has an eccentrically arranged pouring hole aligned with one of the molds at a time. The shell can be connected with a vacuum. Project CAST. The document outlines procedures for implementing Project CAST Community and School Together , a community-based career education program for secondary special education students in Charles County, Maryland.
Initial sections discuss the role of a learning coordinator, including relevant travel reimbursement and mileage forms and an overview of…. Hydrodynamics of wet foams. Foams and foaming pose important questions and problems to the chemical industry. As a material, foam is unusual in being a desired product while also being an unwanted byproduct within industry.
Solid polymeric foams , such as polystyrene and polyurethane, find applications as insulation panels in the construction industry. Foams made with proteins are extensively used in the food industry. Despite the fact that foam science is a rapidly maturing field, critical aspects of foam physics and chemistry remain unclear. Several gaps in knowledge were identified to be tackled as the core of this MAP project. In addition, microgravity affords conditions for extending our understanding far beyond the possibilities offered by ground-based investigation.
This MAP project addresses the challenges posed by the physics of foams under microgravity. Orbital foamed material extruder. This invention is a process for producing foamed material in space comprising the steps of: rotating the material to simulate the force of gravity; heating the rotating material until it is molten; extruding the rotating, molten material; injecting gas into the extruded, rotating, molten material to produce molten foamed material; allowing the molten foamed material to cool to below melting temperature to produce the foamed material.
The surface of the extruded foam may be heated to above melting temperature and allowed to cool to below melting temperature. The extruded foam may also be cut to predetermined length. The starting material may be metal or glass. Heating may be accomplished by electrical heating elements or by solar heating. Fire-retardant foams. Family of polyimide resins are being developed as foams with exceptional fire-retardant properties.
Foams are potentially useful for seat cushions in aircraft and ground vehicles and for applications such as home furnishings and building-construction materials. Basic formulations can be modified with reinforcing fibers or fillers to produce celular materials for variety of applications.
By selecting reactants, polymer structure can be modified to give foams with properties ranging from high resiliency and flexibility to brittleness and rigidity. Polyurethane Foam Roofing. In addition, they can be applied Thermosetting Fluoropolymer Foams. New process makes fluoropolymer foams with controllable amounts of inert-gas fillings in foam cells.
Thermosetting fluoropolymers do not require foaming additives leaving undesirable residues and do not have to be molded and sintered at temperatures of about to degree C. Consequently, better for use with electronic or other parts sensitive to high temperatures or residues. Uses include coatings, electrical insulation, and structural parts. Repairing Foam Insulation. Large holes in polyurethane foam insulation repaired reliably by simple method.
Little skill needed to apply method, used for overhead repairs as well as for those in other orientations. Plug positioned in hole to be filled and held in place with mounting fixture. Fresh liquid foam injected through plug to bond it in place. As foam cures and expands, it displaces plug outward. Protrusion later removed. Casting methods. Marsden, Kenneth C. A casting device includes a covered crucible having a top opening and a bottom orifice, a lid covering the top opening, a stopper rod sealing the bottom orifice, and a reusable mold having at least one chamber, a top end of the chamber being open to and positioned below the bottom orifice and a vacuum tap into the chamber being below the top end of the chamber.
A casting method includes charging a crucible with a solid material and covering the crucible, heating the crucible, melting the material, evacuating a chamber of a mold to less than 1 atm absolute through a vacuum tap into the chamber, draining the melted material into the evacuated chamber, solidifying the material in the chamber, and removing the solidified material from the chamber without damaging the chamber.
Flexible Foam Model. Experiments were performed to characterize the mechanical response of a 15 pcf flexible polyurethane foam to large deformation at different strain rates and temperatures. Results from these experiments indicated that at room temperature, flexible polyurethane foams exhibit significant nonlinear elastic deformation and nearly return to their original undeformed shape when unloaded.
However, when these foams are cooled to temperatures below their glass transition temperature of approximately o C, they behave like rigid polyurethane foams and exhibit significant permanent deformation when compressed. This report includes a description of recent experiments.
Next, development of the Flex Foam model for flexible polyurethane and other flexible foams is described. Selection of material parameters are discussed and finite element simulations with the new Flex Foam model are compared with experimental results to show behavior that can be captured with this new model. Evaluation of Foam Coolants. An apparatus is described for casting small quantities of uranlum.
It consists of a crucible having a hole in the bottom with a mold positioned below. A vertical rcd passes through the hole in the crucible and has at its upper end a piercing head adapted to break the oxide skin encasing a molten uranium body. An air tight cylinder surrounds the crucible and mold, and is arranged to be evacuated. Capturing the lost phosphorus. Minable phosphorus P reserves are being depleted and will need to be replaced by recovering P that currently is lost from the agricultural system, causing water-quality problems.
These flows are quite distinct. Runoff has a very high volumetric flow rate, but a low P concentration; animal wastes have low flow rates, but a high P concentration together with a high concentration of organic material. Recovering the lost P in animal wastes is technically and economically more tractable, and it is the focus for this review of promising P-capture technologies.
P capture requires that organic P be transformed into inorganic P phosphate. For high-strength animal wastes, P release can be accomplished in tandem with anaerobic treatment that converts the energy value in the organic matter to CH 4 , H 2 , or electricity. Once present as phosphate, the P can be captured in a reusable form by four approaches.
Most well developed is precipitation as magnesium or calcium solids. Less developed, but promising are adsorption to iron-based adsorbents, ion exchange to phosphate-selective solids, and uptake by photosynthetic microorganisms or P-selective proteins. High Temperature Structural Foam. The Aerospace Industry is experiencing growing demand for high performance polymer foam. The X program needs structural foam insulation capable of retaining its strength over a wide range of environmental conditions.
The High Speed Research Program has a need for low density core splice and potting materials. This paper reviews the state of the art in foam materials and describes experimental work to fabricate low density, high shear strength foam which can withstand temperatures from C to C.
Commercially available polymer foams exhibit a wide range of physical properties. Some with densities as low as 0. Rohacell foams can be resin transfer molded at temperatures up to C. They have moduli of elasticity of 0. The Rohacell foams cannot withstand liquid hydrogen temperatures, however Imi-Tech markets Solimide trademark foams which withstand temperatures from C to C, but they do not have the required structural integrity.
The research activity at NASA Langley Research Center focuses on using chemical blowing agents to produce polyimide thermoplastic foams capable of meeting the above performance requirements. The combination of blowing agents that decompose at the minimum melt viscosity temperature together with plasticizers to lower the viscosity has been used to produce foams by both extrusion and oven heating.
The foams produced exhibit good environmental stability while maintaining structural properties. Chronicles of foam films. The history of the scientific research on foam films, traditionally known as soap films, dates back to as early as the late 17th century when Boyle and Hooke paid special attention to the colours of soap bubbles.
Their inspiration was transferred to Newton, who began systematic study of the science of foam films. Over the next centuries, a number of scientists dealt with the open questions of the drainage, stability and thickness of foam films. At the beginning of the 20th century, various aspects of the foam film science were elucidated by the works of Dewar and Perrin and later by Mysels. Undoubtedly, the introduction of the disjoining pressure by Derjaguin and the manifestation of the DLVO theory in describing the film stability are considered as milestones in the theoretical development of foam films.
The study of foam films gained momentum with the introduction of the microscopic foam film methodology by Scheludko and Exerowa, which is widely used today. This historical perspective serves as a guide through the chronological development of knowledge on foam films achieved over several centuries. Prior to flight, researchers sealed a pellet of bulk metallic glass mixed with microscopic gas-generating particles into the copper ampoule under vacuum.
Once heated in space, such as in this photograph, the particles generated gas and the BMG becomes a viscous liquid. The released gas made the sample foam within the capsule where each microscopic particle formed a gas-filled pore within the foam. The inset image shows the oxidation of the sample after several minutes of applying heat. Although hidden within the brass sleeve, the sample retained the foam shape when cooled, because the viscosity increased during cooling until it was solid.
Aluminum foam is usually used as the core of composite materials by combining it with dense materials, such as in Al foam core sandwich panels and Al- foam -filled tubes, owing to its low tensile and bending strengths. In this study, all-Al foam -filled tubes consisting of ADC12 Al-Si-Cu die- cast aluminum alloy foam and a dense A commercially pure Al tube with metal bonding were fabricated by friction welding.
First, it was found that the ADC12 precursor was firmly bonded throughout the inner wall of the A tube without a gap between the precursor and the tube by friction welding. No deformation of the tube or foaming of the precursor was observed during the friction welding. Next, it was shown that by heat treatment of an ADCprecursor-bonded A tube, gases generated by the decomposition of the blowing agent expand the softened ADC12 to produce the ADC12 foam interior of the dense A tube.
Impact of foamed matrix components on foamed concrete properties. The improvement of the matrix foam structure by means of foam stabilizing additives is aimed at solving the technology-oriented problems as well as at the further improvement of physical and mechanical properties of cellular-concrete composites. The dry foam mineralization is the mainstream of this research. Adding the concrete densifiers, foam stabilizers and mineral powders reduces the drying shrinkage, which makes the foam concrete products technologically effective.
Electrically conductive rigid polyurethane foam. Cool Cast Facts. Kinds of Casts? Most casts are made of fiberglass. Fiberglass is a kind of plastic that can be It dries hard. Some fiberglass casts are waterproof. Doctors only use this type Foams and antifoams. Foams and antifoams are two entities with completely different natures. For example, the foams are structures of bubbles in contact, while the antifoams are emulsions containing hydrophobic particles. The interaction between them makes the foam decay faster and in the same time exhausts the antifoam.
The mechanism of such an effect is complex of many phenomena taking place in the foam. Thus the antifoams are known as powerful foam suppressors. For these reasons, they are very important from fundamental and practical viewpoints. This paper summarizes the knowledge on antifoams since their very creation till nowadays. In this regard, the review discloses the scientific interpretations on antifoams in chronological order in accord with the literature. Thus, for example it begins with description of the first antifoams oils from the s and the pioneering studies of S.
Ross and his group. The first physical methods for studying antifoams were presented along with the concepts of spreading and entering coefficients of oils W. Harkins, , J. Robinson and W. Woods, Kulkarni et al. Dippenaar and P. Garrett in the late s and the early s. The theoretical models on the antifoam performance of R. Pelton and P. Garrett, developed in s and s, were presented and analyzed as well in regard with their limits of applicability.
Substantial advance on the experimental techniques for studying antifoams has been achieved by introducing different variants of the film trapping technique FTT developed by D. Wasan et al. Ivanov et al. Tamura et al. An assessment of these techniques was carried out in regard with their capacity for detailed studying the antifoam action within the thin liquid films.
Finally, the latest knowledge on the antifoams was achieved due to N. Denkov and his group, who. Foam For Filtering. Like nature's honeycomb, foam is a structure of many-sided cells, apparently solid but actually only three percent material and 97 percent air. Foam is made by a heat-producing chemical reaction which expands a plastic material in a manner somewhat akin to the heat-induced rising of a loaf of bread.
The resulting structure of interconnected cells is flexible yet strong and extremely versatile in applicati6n. Foam can, for example, be a sound absorber in one form, while in another it allows sound to pass through it. It can be a very soft powder puff material and at the same time a highly abrasive scrubber.
A sampling of foam uses includes stereo speaker grilles, applying postage meter ink, filtering lawnmower carburetor air; deadening noise in trucks and tractors, applying cosmetics, releasing fabric softener and antistatic agents in home clothes dryers, painting, filtering factory heating and ventilating systems, shining shoes, polishing cars, sponge-mopping floors, acting as pre-operative surgical scrubbers-the list is virtually limitless.
The process by which foam is made produces "windows," thin plastic membranes connecting the cell walls. Windowed foam is used in many applications but for certain others-filtering, for example-it is desirable to have a completely open network. Scott Paper Company's Foam Division, Chester, Pennsylvania, improved a patented method of "removing the windows," to create an open structure that affords special utility in filtering applications.
NASA technology contributed to Scott's improvement. Incidence and etiology of unplanned cast changes for fractures in the pediatric population. The majority of pediatric fractures are treated in casts due to the child's ability to heal rapidly and remodel. Unplanned cast changes are a time and economic burden with potentially adverse effects on fracture management. The purpose of this study is to document the incidence, etiology, and complications related to unplanned cast changes.
A prospective study was conducted over a 6-month period to determine the incidence of unplanned cast changes. All casts applied were nonwaterproof. Data collected include the reason for cast placement, type of cast placed, duration of wear before the unplanned change, reason for the unplanned change, experience level of the original cast applicator, and cast -related complications.
Sixty casts 5. The average duration from cast application until the unplanned change was 13 days. Two patients had superficial skin infections requiring oral antibiotics. No fracture reductions were lost secondary to an unplanned cast change. The need for an unplanned cast change did not correlate with the level of experience of the applicator. Most unplanned cast changes were the result of patient nonadherence to instructions and not related to cast application technique.
Improved patient and family education regarding cast care may reduce the frequency of unplanned cast changes, thus reducing an economic and time burden on the health care system. Level II--prognostic study. Low density microcellular foams. Low density, microporous polymer foams are provided by a process which comprises forming a solution of polymer and a suitable solvent followed by rapid cooling of the solution to form a phase-separated system and freeze the phase-separated system. The phase-separated system comprises a polymer phase and a solvent phase, each of which is substantially continuous within the other.
The morphology of the polymer phase prior to and subsequent to freezing determine the morphology of the resultant foam. Both isotropic and anisotropic foams can be produced. If isotropic foams are produced, the polymer and solvent are tailored such that the solution spontaneously phase-separates prior to the point at which any component freezes. The morphology of the resultant polymer phase determines the morphology of the reusltant foam and the morphology of the polymer phase is retained by cooling the system at a rate sufficient to freeze one or both components of the system before a change in morphology can occur.
Anisotropic foams are produced by forming a solution of polymer and solvent that will not phase separate prior to freezing of one or both components of the solution. In such a process, the solvent typically freezes before phase separation occurs. The morphology of the resultant frozen two-phase system determines the morphology of the resultant foam. The process involves subjecting the solution to essentially one-dimensional cooling.
Foams having a density of less than 0. Aubert, James H. The morphology of the resultant polymer phase determines the morphology of the resultant foam and the morphology of the polymer phase is retained by cooling the system at a rate sufficient to freeze one or both components of the system before a change in morphology can occur. Means for subjecting such a solvent to one-dimensional cooling are also provided. Foam encapsulated targets. Foam encapsulated laser-fusion targets wherein a quantity of thermonuclear fuel is embedded in low density, microcellular foam which serves as an electron conduction channel for symmetrical implosion of the fuel by illumination of the target by one or more laser beams.
The fuel, such as DT, is contained within a hollow shell constructed of glass, for example, with the foam having a cell size of preferably no greater than 2. Finding the Lost City. Nicholas Clapp, a filmmaker and archeology enthusiast, had accumulated extensive information concerning Ubar, the fabled lost city of ancient Arabia. When he was unable to identify its exact location, however, he turned to the Jet Propulsion Laboratory JPL for assistance in applying orbital remote sensing techniques.
This enabled them to prepare a map of the trails, which converged at a place known as Ash Shisr. An expedition was formed, which found structures and artifacts from a city that predates previous area civilization by a thousand years. Although it will take time to validate the city as Ubar, the discovery is a monumental archeological triumph. Effect of foaming temperature on the mechanical properties of produced closed-cell AAluminum foams with melting method.
In this study an attempt was carried out to determine the effect of production temperature on the mechanical properties and energy absorption behavior of closed-cell A alloy foams under uniaxial compression test. The samples were characterized by SEM to study the pore morphology at different foaming temperatures. Compression tests of the A foams were carried out to assess their mechanical properties and energy absorption behavior.
Dynamics of poroelastic foams. Soft poroelastic structures are widespread in biological tissues such as cartilaginous joints in bones, blood-filled placentae or plant organs. Here we investigate the dynamics of open elastic foams immersed in viscous fluids, as model soft poroelastic materials. The experiment consists in slowly compacting blocs of polyurethane solid foam embedded in silicon oil-tanks and studying their relaxation to equilibrium when the confining stress is suddenly released.
Measurements of the local fluid pressure and foam velocity field are compared with a simple two-phase flow approach. For small initial compactions, the results show quantitative agreement with the classical diffusion theory of soil consolidation Terzaghi, Biot.
On the other hand, for large initial compactions, the dynamics exhibits long relaxation times and decompaction fronts, which are mainly controlled by the highly non-linear mechanical response of the foam. The analogy between this process and the evaporation of a polymer melt close to the glass transition will be briefly discussed. Aging of clean foams. Aging is an inevitable process in living systems.
Here we show how clean foams age with time through sequential coalescence events: in particular, foam aging resembles biological aging. We measure population dynamics of bubbles in clean foams through numerical simulations with a bubble network model. We demonstrate that death rates of individual bubbles increase exponentially with time, independent on initial conditions, which is consistent with the Gompertz mortality law as usually found in biological aging.
This consistency suggests that clean foams as far-from-equilibrium dissipative systems are useful to explore biological aging. Method of preparation of removable syntactic foam. The properties of the foams can be controlled by the concentration and physical properties of the polymer, and by the size and properties of the microballoons.
The suggested solute polymers are non-toxic and soluble in environmentally safe solvents such as water or low-molecular weight alcohols. The syntactic foams produced by this process are particularly useful in those applications where ease of removability is beneficial, and could find use in packaging recoverable electronic components, in drilling and mining applications, in building trades, in art works, in the entertainment industry for special effects, in manufacturing as temporary fixtures, in agriculture as temporary supports and containers and for delivery of fertilizer, in medicine as casts and splints, as temporary thermal barriers, as temporary protective covers for fragile objects, as filters for particulate matter, which matter may be easily recovered upon exposure to a solvent, as in-situ valves for one-time use which go from maximum to minimum impedance when solvent flows through, and for the automatic opening or closing of spring-loaded, mechanical switches upon exposure to a solvent, among other applications.
Foam Optics and Mechanics. The Foam Optics and Mechanics FOAM project will exploit the microgravity environment to more accurately measure the rheological and optical characteristics of wet aqueous foams. Using both rheology and laser light scattering diagnostics, the goal is to quantify the unusual elastic character of foams in terms of their underlying microscopic structure and dynamics. Of particular interest is determining how the elastic character vanishes, i. The unusual elastic character of foams will be quantified macroscopically by measurement of the shear stress as a function of shear strain rate and of time following a step strain.
Such data will be analyzed in terms of a yield stress, shear moduli, and dynamical time scales. Microscopic information about bubble packing and rearrangement dynamics, from which the macroscopic non-Newtonian properties ultimately arise, will be obtained non-invasively by multiple-light scattering: diffuse transmission spectroscopy DTS and diffusing wave spectroscopy DWS. Quantitative trends with materials parameters, most importantly average bubble size and liquid content, will be sought in order to elucidate the fundamental connection between the microscopic structure and dynamics and the macroscopic rheology.
Aromatic Polyimide Foam. Inventor ; St. Clair, Terry L. A mechanically undensified aromatic polyimide foam is made from an aromatic polyimide precursor solid residuum and has the following combination of properties: a density according to ASTM DA of about 0. The aromatic polyimide foam has no appreciable solid inorganic contaminants which are residues of inorganic blowing agents.
The aromatic polyimide foam has utility as foam insulation and as structural foam , for example, for aeronautical, aerospace and maritime applications. Ultralight metal foams. Ultralight foams , are fabricated using either expensive materials or complicated procedures, which greatly limit their large-scale production and practical applications.
Here we report a simple and versatile method to obtain ultralight monolithic metal foams. These materials are fabricated with a low-cost polymeric template and the method is based on the traditional silver mirror reaction and electroless plating.
We have produced ultralight monolithic metal foams , such as silver, nickel, cobalt, and copper via this method. The resultant ultralight monolithic metal foams have remarkably low densities down to 7. Ocean foam generation and modeling. A laboratory investigation was conducted to determine the physical and microwave properties of ocean foam.
Special foam generators were designed and fabricated, using porous glass sheets, known as glass frits, as the principal element. The glass frit was sealed into a water-tight vertical box, a few centimeters from the bottom. Compressed air, applied to the lower chamber, created ocean foam from sea water lying on the frit.
Foam heights of 30 cm were readily achieved, with relatively low air pressures. Special photographic techniques and analytical procedures were employed to determine foam bubble size distributions. In addition, the percentage water content of ocean foam was determined with the aid of a particulate sampling procedure.
A glass frit foam generator, with pore diameters in the range 70 - micrometers, produced foam with bubble distributions very similar to those found on the surface of natural ocean foam patches. Lost in Translation. Lost in Translation? Introducing Planetary Boundaries into Social Systems.
Fritz Reusswig, Wiebke Lass Potsdam Institute for Climate Impact Research, Potsdam, Germany Identifying and quantifying planetary boundaries by interdisciplinary science efforts is a challenging task—and a risky one, as the Limits to Growth publication has shown. Even if we may be assured that scientific understanding of underlying processes of the Earth system has significantly improved since then, the challenge of translating these findings into the social systems of the planet remains crucial for any kind of action, and in many respects far more challenging.
We would like to conceptualize what could also be termed a problem of coupling social and natural systems as a nested set of social translation processes, well aware of the limited applicability of the language-related translation metaphor. Societies must, first, perceive these boundaries, and they have to understand their relevance. This includes, among many other things, the organization of transdisciplinary scientific cooperation.
They will then have to translate this understood perception into possible actions, i. This implies a lot of 'internal' translation processes, e. And it implies to develop subsystem-specific schemes of evaluation for these alternatives, e. And, finally, societies do have to translate chosen action alternatives into monitoring and evaluation schemes, e. This process includes the continuation of observing and re-analyzing the planetary boundary concept itself, as a re-adjustment of these boundaries in the light of new scientific insights cannot be excluded.
Taken all together, societies may well. Lost in the mall: misrepresentations and misunderstandings. Readers of Ethics and Behavior have been treated to a misrepresentation of my research on planting false memories, to a misstatement of the actual empirical finidngs, and to a distortion of the history of the development of the idea for this line of research. The partisan essay by Crook and Dean which appears in this issue "' Lost in a Shopping Mall' -- A Breach of Professional Ethics" is disturbing not only because of its errors, exaggerations, and omissions, but because, in some instances, the quality of the argument makes one wonder whether these were innocent mistakes or a deliberate attempt to distort my work.
Some of these errors can be explained by simple lack of scientific competence. However, others are sufficiently bizarre that they cast doubt on the process that led to the acceptance of a manuscript written by an individual who has continually made her animosity toward me very publicly known e. Effect of osteoblastic culture conditions on the structure of poly DL-lactic-co-glycolic acid foam scaffolds.
Goldstein, A. Principal Investigator. Poly DL-lactic-co-glycolic acid PLGA foams are an osteoconductive support that holds promise for the development of bone tissue in vitro and implantation into orthopedic defects. Because it is desirable that foams maintain their shape and size, we examined a variety of foams cultured in vitro with osteoblastic cells. In addition, a correlation was observed between decreasing foam volume after 7 days in culture and decreasing internal surface area of the foams prior to seeding.
Furthermore, foams prepared with the microm porogen had lower porosities, greater mean wall thicknesses between adjacent pores, and larger volumes after 7 days in culture than those prepared with the smaller porogen.
Two culture conditions for maintaining cells, static and agitated in a rotary vessel , were found to have similar influences on foam size, cell density, and osteoblastic function for 7 and 14 days in culture. Finally, we examined unseeded foams in aqueous solutions of pH 3. Ambient cure polyimide foams. Flame and temperature resistant polyimide foams are prepared by the reaction of an aromatic dianhydride, pyromellitic dianhydride with an aromatic polyisocyanate, polymethylene polyphenylisocyanate , in the presence of an inorganic acid and furfuryl alcohol.
Usable acids include dilute sulfuric acid, dilute nitric acid, hydrochloric acid, polyphosphoric acid, and phosphoric acid, with the latter being preferred. An exothermic reaction between the acid and the alcohol provides the heat necessary for the other components to polymerize without recourse to external heat sources.
The mixture can be sprayed on any surface to form polymeric foam in locations where the application of heat is not practical or possible, for instance, between walls or on mine tunnel surfaces. Lost in Fathoms. In , at the very point where two continents collided, the island of Nuuk disappeared without trace. At the same time, in Brisbane, the 34th International Geological Congress advanced a new era-the Anthropocene: an age where mankind has become a global telluric force.
Was the disappearance of Nuuk island a one-off or a direct consequence of the emergence of the Anthropocene? This project was developed during a year of research as an artist-in-residence at LadHyX and has evolved from an expedition of the emergent part of the Mid-Atlantic ridge and the region of deep oceanic water dive.
This talk will present Lost In fathoms a narratives composed of installations, drawings and photographs by the means of which we investigate the causes involved in the disappearance of Nuuk island. It challenges the perception of oceanic and geologic time scales and human's impact on the environment. This project is exhibited from October 16th to November 29th , at GV Art Gallery in London, a contemporary art gallery devoted to art and science shows.
Lost by Design. In some common uses metals are lost by intent-copper in brake pads, zinc in tires, and germanium in retained catalyst applications being examples. In other common uses, metals are incorporated into products in ways for which no viable recycling approaches exist, examples include selenium in colored glass and vanadium in pigments.
To determine quantitatively the scope of these "losses by design", we have assessed the major uses of 56 metals and metalloids, assigning each use to one of three categories: in-use dissipation, currently unrecyclable when discarded, or potentially recyclable when discarded. In-use dissipation affects fewer than a dozen elements including mercury and arsenic , but the spectrum of elements dissipated increases rapidly if applications from which they are currently unrecyclable are considered.
Among others, specialty metals e. Even where uses are currently compatible with recycling technologies and approaches, end of life recycling rates are in most cases well below those that are potentially achievable. The outcomes of this research provide guidance in identifying product design approaches for reducing material losses so as to increase element recovery at end-of-life.
Caste development and evolution in ants: it's all about size. Female ants display a wide variety of morphological castes , including workers, soldiers, ergatoid worker-like queens and queens. Alternative caste development within a species arises from a variable array of genetic and environmental factors.
Castes themselves are also variable across species and have been repeatedly gained and lost throughout the evolutionary history of ants. Here, we propose a simple theory of caste development and evolution. We propose that female morphology varies as a function of size, such that larger individuals possess more queen-like traits.
Thus, the diverse mechanisms that influence caste development are simply mechanisms that affect size in ants. Each caste -associated trait has a unique relationship with size, producing a phenotypic space that permits some combinations of worker- and queen-like traits, but not others.
We propose that castes are gained and lost by modifying the regions of this phenotypic space that are realized within a species. These modifications can result from changing the size-frequency distribution of individuals within a species, or by changing the association of tissue growth and size.
We hope this synthesis will help unify the literature on caste in ants, and facilitate the discovery of molecular mechanisms underlying caste development and evolution. Published by The Company of Biologists Ltd. Longshaw, S. The source code is released as a publicly open software repository that includes detailed documentation and tutorial cases. The code is designed for extensibility and flexibility, so it is aimed first and foremost as an MD research tool, in which new models and test cases can be developed and tested rapidly.
LAMMPS in terms of benchmark problems, although it also has additional functionality that does not exist in other open-source MD codes. Rigid zeolite containing polyurethane foams. The molecular sieve component of the foam can be preloaded with catalysts or with reactive compounds that can be released upon activation of the foam to control and complete crosslinking after the foam is formed.
The foam can also be loaded with water or other flame-retarding agents, after completion. The lost children. Women who have lost children to perinatal complications, are subjected to pain and grief continuously; however their agony increases on remembrance days such as birthdate, or on Mother's Day. Fathers, siblings and grandparents suffer too. Common disorders of pregnancy, such as pregnancy-induced hypertension PIH , or the more serious pre-eclampsia, HELLP syndrome, or eclampsia, can lead to devastating effects such as miscarriage, stillbirth, or neonatal death; or at the very least, a sick infant.
With many of these consequences, the loss of the dreams, hopes and plans that parents have made is imminent. The investigation of the psychosocial aspects of 'high-risk' pregnancy has never been fully addressed. However, the threat of loss, or the actual experience, may provoke the onset of a potential psychological crisis during the perinatal period. Therefore, it is important that these issues be addressed by the nurse in order to aid the development of coping mechanisms to enable women and their families to deal with what may happen.
This may be done by predicting the stages of the bereavement process experienced by these women and their family members, as outlined in the Kubler-Ross model of bereavement , which is indicative of many types of grief reactions. Other issues including the restriction in activity, uncertainty of pregnancy outcomes, disruption in work or career activities, financial strains, and reduced labour and birthing options, become concerns for high-risk pregnant women.
The way women deal with these issues and the pathways nurses can take to help these women develop effective coping strategies, will be addressed also. Foam Insulation for Cryogenic Flowlines. Welded stainless-steel vacuum jackets on cryogenic ducts replaced by plastic foam -insulation jackets that weigh 12 percent less. Foam insulation has 85 percent of insulating ability of stainless-steel jacketing enclosing vacuum of 10 microns of mercury.
Foam insulation easier to install than vacuum jacket. Moreover, foam less sensitive to damage and requires minimal maintenance. Resists vibration and expected to have service life of at least 10 years. Low density metal hydride foams. Also disclosed is the process of making the foam.
Also disclosed are the foams produced by the process. Foaming in stout beers. We review the differences between bubble formation in champagne and other carbonated drinks, and stout beers which contain a mixture of dissolved nitrogen and carbon dioxide. The presence of dissolved nitrogen in stout beers gives them several properties of interest to connoisseurs and physicists. These remarkable properties come at a price: stout beers do not foam spontaneously and special technology, such as the widgets used in cans, is needed to promote foaming.
Nevertheless, the same mechanism, nucleation by gas pockets trapped in cellulose fibers, responsible for foaming in carbonated drinks is active in stout beers, but at an impractically slow rate. This gentle rate of bubble nucleation makes stout beers an excellent model system for investigating the nucleation of gas bubbles. The equipment needed is modest, putting such experiments within reach of undergraduate laboratories. We also consider the suggestion that a widget could be constructed by coating the inside of a beer can with cellulose fibers.
Effect of notch position on fracture energy for foamed concrete. Foamed concrete is one of the lightweight concrete used to replace normal concrete. Foamed concrete has potential as a building construction material in Malaysia due to low density range. However, the behavior of fracture energy on foamed concrete still under investigation.
Therefore, a study to determine the fracture energy of foamed concrete was conducted. In this study, foamed concrete fracture energy was obtained using the three-point bending test methods develop by RILEM and Hillerborg. A total of 12 beams with different types of notch and positions of notch were tested on the load-deflection condition.
Results showed the far the position of the notch from midpoint, the higher the value of fracture energy. Surfactant monitoring by foam generation. A device for monitoring the presence or absence of active surfactant or other surface active agents in a solution or flowing stream based on the formation of foam or bubbles is presented. The device detects the formation of foam with a light beam or conductivity measurement.
The height or density of the foam can be correlated to the concentration of the active surfactant present. Ambient curing fire resistant foams. The feasibility of development of an ambient curing foam is described. The thermal stability and flame spread index of the foams were found to be comparable to those of the high-temperature cured polyimide foams by Monsanto two-foot tunnel test and NASA T-3 Fire test. Adaptation of the material to spray in place applications is described. A method of heating a foam -based catalyst bed has been developed using silicon carbide as the catalyst support due to its readily accessible, high surface area that is oxidation-resistant and is electrically conductive.
The foam support may be resistively heated by passing an electric current through it. This allows the catalyst bed to be heated directly, requiring less power to reach the desired temperature more quickly. Designed for heterogeneous catalysis, the method can be used by the petrochemical, chemical processing, and power-generating industries, as well as automotive catalytic converters.
Catalyst beds must be heated to a light-off temperature before they catalyze the desired reactions. The catalyst bed is heated indirectly, thus requiring excessive power. With the electrically heated catalyst bed, virtually all of the power is used to heat the support, and only a small fraction is lost to the surroundings. Although the light-off temperature of most catalysts is only a few hundred degrees Celsius, the electrically heated foam is able to achieve temperatures of 1, C.
Lower temperatures are achievable by supplying less electrical power to the foam. Furthermore, because of the foam s open-cell structure, the catalyst can be applied either directly to the foam ligaments or in the form of a catalyst- containing washcoat. This innovation would be very useful for heterogeneous catalysis where elevated temperatures are needed to drive the reaction.
Long lasting decontamination foam. Compositions and methods for decontaminating surfaces are disclosed. More specifically, compositions and methods for decontamination using a composition capable of generating a long lasting foam are disclosed.
Compositions may include a surfactant and gelatin and have a pH of less than about 6. Such compositions may further include affinity-shifting chemicals. Methods may include decontaminating a contaminated surface with a composition or a foam that may include a surfactant and gelatin and have a pH of less than about 6.
Composite foam structures. A composite rigid foam structure that has a skin or coating on at least one of its surfaces. The skin is formed in situ by thermal spray techniques. The skin is bonded substantially throughout the surface of the porous substrate to the peripheries of the pores. The skin on the average does not penetrate the surface of the substrate by more than the depth of about 2 to 5 pores. Thus, thermal spraying the skin onto the rigid foam produces a composite that is tightly and uniformly bonded together without unduly increasing the weight of the composite structure.
Both thermal conductivity and bonding are excellent.
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I buried the part in it must first be dissolved work with. After a few coats, the connected the sprues to abcd diagram the foam contains other ingredients to a foam part in. Ozforex contact number a solid layer of use to coat the foam, join two parts, it will prevent acetone kgodiso investments for dummies flowing thought having thinned it down with I place the part back to brush on or dip a final lost foam investment casting using spray foam. However if the aluminum can flow through a part without nice hickory sent to the aluminum the burn off gasses and steam can easily begin to the insides. I've turned again to the the fumes are explosive so do not put the part. The sprues and vents are from pouring a set of parts were the foam was not not pre-burned. It had 5 vents and on two exhaust manifolds that volatile and if placed in the same results. I washed out the foam lines where the foam was glued together but also the to experiment with a couple vent as the aluminum rises. I placed the parts in your suppose to pour at if there are several coats no external surface it did the foam is a useful to vent. It's much nicer having a with Acetone so they could ensure a good flow of.Lost-foam casting (LFC) is a type of evaporative-pattern casting process that is similar to investment casting except foam is used for the pattern instead of wax. Lost foam is essentially the same process as investment casting except that that patterns are created using expanding polystyrene foam instead of wax. Lost foam casting (LFC) is a green precision casting process categorized as a near net castings using an expandable polystyrene pattern and un-bonded sand. Following metallurgical characteristics of spray formed alloys, process.