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Regenerable carbon dioxide (CO2)/moisture removal techniques that reduce the expendables and logistics requirements are needed to sustain people undertaking extravehicular activities (EVA) for the Space Station. Life Systems, working with NASA, has been developing the Electrochemically Regenerable CO2 Absorption (ERCA) technology to replace the nonregenerable lithium hydroxide (LiOH) absorber for the, advanced Portable Life Support System (PLSS).(1) During EVA the ERCA uses a mechanism involving gas absorption into a liquid absorbent for the removal and storage of the metabolically produced CO2 and moisture. Following the EVA, the expended absorbent is regenerated on-board the Space Station by an electrochemical concept based on the Life Systems' Electrochemical CO2 Concentrator (EDC) technology. The ERCA concept has the ability to effectively satisfy the high metabolic CO2 and moisture removal requirements of PLSS applications.

Regenerable carbon dioxide (CO2) and moisture removal techniques that reduce expendables and logistics requirements are needed to sustain people undertaking extravehicular activities for the Space Station. Life Systems, working with National Aeronautics and Space Administration has been developing and investigating the ways to advance the Electrochemically Regenerable CO2 and Moisture Absorption (ERCA) technology to replace the nonregenerable solid lithium hydroxide absorber for the advanced Portable Life Support System (PLSS). During extravehicular activities the ERCA technique uses a mechanism involving gas diffusion and absorption into liquid absorbent for the removal and storage of the metabolically produced CO2 and moisture. Following the extravehicular activities, the expended absorbent is regenerated on-board the Space Station by an electrochemical method which restores the CO2 and moisture absorption capabilities of the absorbent.

This paper describes the development of a prototype fluid pumping system for incorporation into a miniaturized flow injection analyzer. The strategy couples the well-established capabilities of reagent-based flow injection analyses (FIA) with our novel concepts for the design of a miniaturized, low-power pumping system, i.e., an electrochemically-driven micropump. The basis of pump actuation relies on the electrochemically-induced surface tension changes at the electrolyte/mercury interface, resulting in a “piston-like” pumping process devoid of mechanically moving parts. We present herein the results from the preliminary performance tests of a miniaturized fluid flow system with the micropump. As described, the flow rates and pumping displacement volumes have been studied as a function of the amplitude and the frequency of the applied voltage waveform.

A high-temperature, low-power electrochemically-driven fluid cooling pump is currently being developed by Lynntech, Inc. With no electric motor and minimal lightweight components, the pump is significantly lighter than conventional rotodynamic and displacement pumps. Reliability and robustness is achieved with the absence of rotating or moving components (apart from the bellows). Lynntech has recently demonstrated the feasibility of long term pump operation at temperatures of up to 100 °C, and extended storage at temperatures as low as -60 °C. Characteristics of the electrochemically-driven pump are described and the benefits of the technology as a replacement for electric motor pumps in mechanically pumped single-phase fluid loops (MPFL), such as that used in the Mars Pathfinder (MPF), is discussed.

OVER THE NEXT SEVERAL YEARS, electrochromic mirrors will be introduced for use on automobiles, initially as interior mirrors and later for the exterior. Electrochromic mirrors have variable reflectivity and this offers an opportunity to select a reflectance level that avoids glare, but that maintains rear vision. Human factors studies can relate driver discomfort to incident glare and the results can be incorporated into a fully automatic mirror whose reflectivity varies dynamically to suit changing driving conditions. In automatic mode, the electrochromic mirror responds appropriately to all driving situations, and mirror operation is transparent to the driver with smooth response and no unexpected change. This paper explains the scientific basis of electrochromism and traces development of the technology to its present applications. Electrochromic mirrors presently available worldwide are reviewed.

Possible active and passive glass is reviewed in terms of “cool automotive glass”. Electrochromics, electrochromic materials, and electrochromic device performance criteria are evaluated as a most promising active glass to control the interior light and heat level of a car. Various automotive applications of electrochromic glasses are also reviewed.

The state of the art in electrochromic materials is briefly reviewed. These materials have potential for architectural and automotive applications for they provide control of radiant solar energy transmission. Optical properties of these materials can be reversibly changed by electrochemical oxidation and reduction. These optically switchable materials can provide control of solar heat load on air conditioning systems, reduce glare for rear view mirrors, and enhance privacy in an automobile. The main features of the electrochromic characteristics of the best-known groups of materials are described. The properties of some of the well-known materials such as WO3, Ni (OH)2, viologens, polyaniline and Prussian Blue are discussed with particular reference to the mechanism of electrochromic reactions.

A transparent, solid-state, electrochromic device is described. It demonstrates deep switching in the near infrared and visible spectral regions and good room temperature cycling stability. The response appears reasonably uniform over a 14 cm x 28 cm area, which gives hope for achieving large parts for cockpit and cabin windows. The reversible darkening of the transparency, controlled by an applied voltage or current, has potential application in aircraft to reduce glare and solar heat load to pilots and passengers. The active material in the device is a thin tungsten oxide film which is incorporated into a complex, multilayered structure, essentially that of a transparent battery. The performance of the window is discussed in terms of its configuration, its similarities with commercial batteries and issues critical to aircraft.

External corrosion of automotive heat exchangers, mainly radiators, has in recent years become a problem in some cases. The reasons for the corrosion attacks are a combination of air pollution on one side and road salting or tropical marine climate on the other. This paper deals with actions taken to improve the corrosion resistance of copper/brass radiators. Rapid corrosion of the tubes due to dezincification which gave early radiator leakages was solved by introducing arsenic and phosphorous containing brass qualities (1). Corrosion of fins and solder has been tackled by different types of coatings (2, 3). Copper strips that are zinc coated before the fin production are a new product for large scale application (4). Solder coated strips have been used since many years but are expensive and heavy. Organic coatings applied on complete radiators have been tested for a couple of years. The black painting that is normally used on radiators does not give any corrosion prevention.

Heat transfer from the flame kernel to the electrodes during the spark ignition process is of interest for predicting the minimum ignition energy at a given engine operating condition. Experiments conducted in a constant volume bomb at near ignition limit conditions with small and large electrode surface areas (comparable to J gap plug), coupled with a phenomenological model, show the lumped heat transfer coefficient to range from 150-200 W/m2 K during the first 3 milliseconds of the ignition period. An additional analytical approach that uses the measured time dependent kernel-electrode contact areas gives reasonable agreement with the experimentally determined heat transfer coefficient and demonstrates that the dominant mechanism is thermal conduction. Heat loss from the flame kernel is comparable to the net ignition energy for the small electrodes after 3 milliseconds while that for the large electrodes is shown to equal the net ignition energy within 800 microseconds.

The units of electric conductivity are defined and the problems associated with conventional instruments are mentioned. The principle of operation of the electrodeless conductivity meter is explained along with manufacturing details. Applications to process control are mentioned and barriers to wider acceptance are discussed.

Nano graphite (50-60nm) displays excellent lubricating property and agglomerates easily into big particles in acidic electrolyte, which lead to its lower content in composite coatings. The influence of nano carbon particles concentration in bath, current density, temperature and agitating method on the properties of electrodeposited black Cr-C composite coating and wearing resistance of Cr-C coating were studied in this paper. The surface morphology and phase structure of the coatings were analyzed by means of scanning electronic microscopy (SEM) and X-ray diffractometer (XRD), and its microhardness was determined by micrometer. The results showed that the maximum microhardness of black Cr-C nano-composite coating was 10.8 Gpa, the maximum vol.% in coating was 8.82, which formed under current density of 100A/dm2, temperature of 15°C, ultrasonic wave plus slow mechanical agitation. The optimum particle content in electrolyte was 10g/l.

The type of surface that is used in the cylinder bore of a small aluminum engine is a critical item. This paper describes all the techniques presently used: the iron liner, the chrome plated cylinder, the nickel-silicon carbide composities, the Reynolds 390 aluminum alloy, and aluminum cylinders with chrome plated pistons. The emphasis is on the electrodeposits used in cylinder bores.

Outboard motors use aluminum die-cast components extensively to cut down their weight. They are also cooled directly by the raw water including saline water. Corrosion protection is the critical issue for outboard motors because of these characteristics. Currently, the coating is the primary measures taken to assure the corrosion resistance and to give originality to the appearance. However, the complicated cooling passages cannot be coated appropriately with the spray-paint process. Such disadvantages can be compensated by the electrodeposition coating technique. In the case of electrodeposition coating, the coating film is generated electrically in the coating material bath by means of deposition. The process is widely applied to the automobile bodies made of steel plate, because it provides higher transfer efficiency and lower VOC (VOLATILE ORGANIC COMPOUNDS) emission.

Electrodialysis is used to remove salts from waste or other water streams, to yield a concentrated brine and a substantially deionized product water. During the electrodialysis process, the boundary layer adjacent to the ion selective membrane can become depleted of ions, resulting in severe pH changes sometimes accompanied by precipitation, and power losses, by a process known as “water-splitting.” In order to optimize the applied electric current density, to achieve maximum deionization without exceeding the limiting current at any point along the path, a simulation program has been created to plot ion concentrations and fluxes, and cell current densities and voltages, along the electrodialysis path. A means for tapering the current density along the path is recommended.

Electroemissive (ESTHER) devices are thin sheets - similar to solar cells - whose infrared emissivity can be varied reversibly by electrical charging. Bonded to the external surfaces of spacecraft radiators they can be used for the active control of the Irradiated heat by consuming negligible electrical energy. The window to a revolutionary new thermal control design technology for spacecraft may be opened.

A new orifice plate (OP) for advanced fuel injection characteristics is presented. The OP is designed to optimize the air-fuel mixture generation and transportation within individually shaped manifold geometries of spark-ignition engines. To generate the suitable spray characteristics, the basic OP design and its flow characteristics have some features originating from the well known turbulence nozzle principle: Turbulence generating flow deflections within the OP are achieved by superimposing layers containing flow cavities, which are displaced from one another. The flow deflections effect atomization and define the spatial spray beam orientation. A great variety and a high volume of precisely structured, low cost OPs can be produced daily by micromachining the layers in electroformed nickel. The flow cavities and outer dimensions of each layer are shaped by photo-resist structures.

Electrofuels produced from renewable hydrogen (H2) and captured carbon dioxide (CO2) can be sustainable and carbon-neutral. Paraffinic electrodiesel (e-diesel) can be produced via Fischer-Tropsch synthesis with fuel properties resembling hydrotreated vegetable oils. Electrofuels can be also oxygenated compounds, such as oxymethylene dimethyl ethers (OMEn), having different chain lengths. We studied emissions using paraffinic diesel mimicking e-diesel and its blend with 10% of OME3-5, which has diesel-type fuel properties, in comparison with normal EN590 diesel fuel. An intensive measurement campaign was performed with a modern diesel engine without exhaust aftertreatment to study the effect of fuel on the engine-out emissions. Measurements with the RMC-C1 cycle included detailed characterization of gaseous, particle and polyaromatic hydrocarbon (PAH) emissions having adverse effects on health and the environment.

The benefits of bake-hardening steels for body applications in the automotive industry are well known since several years. These steels offer the potential of weigth savings without major loss of formability. Thus this group of high-strength steels is the first to find broad application for exposed panels. This paper sums up the different concepts of producing cold-rolled electrogalvanized and hot-dip galvanized bake-hardening steels. These concepts are critically discussed from the point of view of stable production. Important aspects for batch annealed or continuously annealed steels are the control of grain size and temper rolling. New hot-dip galvanized bake-hardening steels have been developed; as a result of degassing to ultra low carbon contents in modern vacuum treatment facilities. Beside bake-hardening effects special emphasis is given to the strain-hardening behaviour and to the ageing resistance of bake-hardening steels.

The corrosion performance of 17 hot dip and electrolytic zinc and zinc alloy coated steel samples exposed for five consecutive winters in undervehicle tests is reported in this paper. The program initiated by Dofasco in 1981, used two commercial trucks operating in the deicing salt/snow belt region of Southern Ontario, Canada. Results of the phosphated and cathodic primed coupons confirmed our previous observations on unpainted coupons that the hot dip coated steels with the thicker coatings outperformed the electrolytic coated steels. A new test program Has started in 1984. This program uses paired “t” test statistics to compare the undervehicle corrosion performance of hot dip and electrogalvanized coupons of similar coating mass. Results after one and two winters will be presented.