Outer space

The space environment, seen as beginning in the center of the earth, extends to infinity. In the past few decades outer space has been penetrated. These initial successful steps depended on a number of factors, one of which was the use of plastics. As in terrestrial uses, plastics have their place in space. 

Plastics will continue to be required in space applications from rockets to vehicles for landing on other planets. The space structures, reentry vehicles, and equipment such as antennas, sensors, and an astronaut s personal communication equipment that must operate outside the confines of a spaceship will encounter bizarre environments. Temperature extremes, thermal stresses, micrometeorites, and solar radiation are sample conditions that are being encountered successfully that include the use of plastics. 

Perhaps the most striking phenomenon encountered in outer space is the wide variation in temperature that can be experienced on spacecraft surfaces and externally located equipment. Temperatures and temperature gradients not ordinarily encountered in the operation of ground or airborne structures and equipment are ambient conditions for spacecraft equipment. On such hardware, not suitably protected externally or housed deep within the space vehicle in a controlled environment, these temperature extremes can wreak destruction. Designers of earthbound 

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For appbcations where oxygen can be excluded, eg, in outer space. Figure 10 shows that 10-yr use projections exceed 200°C for Parylenes N, C, and D. Conventional antioxidants, incorporated during or after VDP, can extend the life of the parylenes at elevated temperatures (39). 

The ease with which the separated products leave the bowl determines the richness of the fat. Fluid whole milk enters the separator under pressure from a positive displacement pump or centrifugal pump with flow control (Fig. 1). The fat (cream) is separated and moves toward the center of the bowl, while the skimmed milk passes to the outer space. There are two spouts or oudets, one for cream and one for skimmed milk. Cream leaves the center of the bowl with the percentage of fat ( 30 40%) controlled by the adjustment of a valve, called a cream or skim milk screw, that controls the flow of the product leaving the field of centrifugal force and thus affects the separation. 

In a vacuum, uncoated molybdenum metal has an unlimited life at high temperatures. This is also tme under the vacuum-like conditions of outer space. Pure hydrogen, argon, and hehum atmospheres are completely inert to molybdenum at all temperatures, whereas water vapor, sulfur dioxide, and nitrous and nitric oxides have an oxidizing action at elevated temperatures. Molybdenum is relatively inert to carbon dioxide, ammonia, and nitrogen atmospheres up to about 1100°C a superficial nitride film may be formed at higher temperatures in the latter two gases. Hydrocarbons and carbon monoxide may carburize molybdenum at temperatures above 1100°C. 

Life-Support Applications. Exploration of outer space by humans has focused considerable attention on maximum as weU as minimum limits in the oxygen content of life-support atmospheres. Above the earth, both the atmospheric pressure and the partial pressure of oxygen decrease rapidly. The oxygen content of air remains constant at 20.946% to an altitude of ca 20 km, after which it decreases rapidly (1). 

The abihty to remove heat from electrophoretic systems has severely limited the maximum capacity of these systems in terms of how large or thick the systems can be. Electrophoretic separations have been performed on space flights because the effect of gravity in outer space is small and mixing from heating is negligible. Whereas electrophoresis in outer space has been accompHshed (10), the economics for a scaleable process have not (see Space processing). 

If metal surfaces are thoroughly cleaned in vacuum it is almost impossible to slide them over each other. Any shearing force causes further plasticity at the junctions, which quickly grow, leading to complete seizure (p > 5). This is a problem in outer space, and... 

Nowadays, there doesn t really exist a liquid, condition, or pump operating situation that cannot be sealed suecessflilly with a mechanical seal. With the help of mechanical seals, man has been able to explore the extreme pressures of the oeean depths, and the extreme vacuum of outer space. 

Earth s atmosphere as seen from outer space. (National Aeronautics and Space Administration)... 

In addition to ordinai y matter, scientists have evidence for the existence in the universe of dark matter. Some of the dark matter is ordinai y matter, such as dust in outer space and planets going around other stars. Astronomers cannot see ordinai y dark matter because any light coming from such matter is too faint to be observed in telescopes. However, most of the dark matter in the universe is believed not to be ordinary matter. At the present time it is not known what this mysterious dark matter is, or what it is made of. Scientists know that this dark matter exists because it exerts a gravitational force on stars (which are made of ordinary matter), causing the stars to move faster than they otherwise would. According to present estimates, there is perhaps five times as much dark matter in the universe as ordinary matter. 

A non-uegligible fraction of the solar radiation incident on the earth is lost by reflection from the top of the atmosphere and tops of clouds back into outer space. For the radiation penetrating the earth s atmosphere, some of the incident energy is lost due to scattering or absorption by air molecules, clouds, dust and aerosols. The radiation that reaches the earth s surface... 

Cyanogen gas, CjN has been found in foe gases of outer space. It can react with fluorine to form carbon tetrafluoride and nitrogen trifluoride. 

Very light gases, notably hydrogen and helium, tend to escape from the earths atmosphere. The hydrogen you generate in the laboratory today is well on its way into outer space tomorrow. A similar situation holds with helium, which is found in very limited quantities mixed with natural gas in wells below the earths surface. If helium is allowed to escape, it is gone forevei and our supply of this very usefiil gaseous element is depleted. 

The escape velocity required for gas molecules to overcome the earths gravity and go off to outer space is 1.12 X 103m/s at 15°C Calculate die molar mass of a species with that velocity. Would you expect to find He and H2 molecules in the earth s atmosphere How about argon atoms ... 

Radioastronomers have detected the isoformyl ion, HCO+, in outer space. Write the Lewis structure for this ion. 

In the twentieth century, Jell-O found its way into salads, song ( A Fine Romance from the Rogers and Astaire musical Swing Time in 1936— You take romance, I ll take Jell-O ), academic conferences (the Smithsonian Institution s 1991 symposium on Jell-O included a session on Jell-O wrestling) and outer space. Dr. Shannon W. Lucid, an American mother of three, served Jell-O to Russian astronauts on the Mir Station in 1996 on Easter Sunday. 

Orbital Bomb. A satellite contg a nuclear warhead which circles the earth in a low orbit and which can be commanded to descend on a particular target. No such weapons are now known to be operational, and their deployment would be prohibited under the terms of the Outer Space Treaty of 1966. However, this treaty does not prohibit anything making less than a full circle around the earth, hence the FOBS... 

In a cycle of operation the liquid enters port A and fills the spaces 1 and 3, thus forcing the piston to oscillate counterclockwise opening spaces 2 and 4 to port B. Because of the partition, the piston moves downwards so that space 3 is cut off from port A and becomes space 4. Further movement allows the exit port to be uncovered, and the measured volume between hub and piston is then discharged. The outer space 1 increases until the piston moves upwards over the partition and space 1 becomes space 2 when a second metered volume is discharged by the filling of the inner space 3. Meters of this type will handle flows of between about 0.005 and 15 litres/s. 

Nature abhors a vacuum. True On Earth, it is certainly difficult to remove the gas from a container, thereby generating and maintaining a vacuum—the absence of gas. In outer space, on the other hand, a vacuum is the mle rather than the exception. Most of the volume of the universe is nearly empty space, close to a perfect vacuum. If a spacecraft sprang a leak, its gaseous atmosphere would quickly escape into that vacuum. Perhaps it would be better to say that conditions on Earth are unfavorable for vacuums. 

Why bother to remove the gases from a small volume of space High vacuum Is used In chemistry and physics research to achieve any of the following conditions the absence of molecular collisions, the maintenance of an ultraclean environment, or a simulation of conditions in outer space. 

Rudiger, W., Chlorophyll metabolism from outer space down to the molecular level, Phytochemistry, 46, 1151, 1997. 

Background Radiation—The amount of radiation to which a member of the general population is exposed from natural sources, such as terrestrial radiation from naturally occurring radionuclides in the soil, cosmic radiation originating from outer space, and naturally occurring radionuclides deposited in the human body. 

If Earth was monitored from outer space the annual mean values would show an effective temperature of 254.2 K, where the incoming SWR is balanced by the OLR, i.e., a zero net heat flow. Detailed measurements on this long... 

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