Showing papers on "Energy source published in 1975"

Microbiological basis of phosphate removal in the activated sludge process for the treatment of wastewater.

Abstract: Several strains resembling members of theAcinetobacter-Moraxella-Mima group of bacteria were isolated from activated sludge-type sewage treatment plants designed for phosphate removal. The bacteria are obligate aerobes but utilize as carbon and energy sources low-molecular intermediates generated anaerobically, particularly acetate and ethanol. These bacteria can be shown to be responsible for the phosphate luxury uptake occurring in these treatment plants. The bacteria are physiologically unusual in that they perform luxury uptake of phosphates in a complete growth medium. Phosphate release occurs on addition of a carbon source to the carbon-starved bacteria, lowering pH or both. The bacteria persist in the system by virtue of their ability to form floc.

Analysis of Multidimensional Conduction Phase Change Via the Enthalpy Model

Abstract: The basis of the enthalpy model for multidimensional phase change problems in media having a distinct phase change temperature is demonstrated, and subsequent numerical applications of the model are carried out. It is shown that the mathematical representation of the enthalpy model is equivalent to the conventional conservation equations in the solid and liquid regions and at the solid-liquid interface. The model is employed in conjunction with a fully implicit finite-difference scheme to solve for solidification in a convectively cooled square container. The implicit scheme was selected because of its ability to accommodate a wide range of the Stefan number Ste. After its accuracy had been established, the solution method was used to obtain results for the local and surface-integrated heat transfer rates, boundary temperatures, solidified fraction, and interface position, all as functions of time. The results are presented with SteFo (Fo = Fourier number) as a correlating parameter, thereby facilitating their use for all Ste values in the range investigated. At low values of the Biot number, the surface-integrated heat transfer rate was relatively constant during the entire solidification period, which is a desirable characteristic for phase change thermal energy storage.

Extraction of hydrocarbons in situ from underground hydrocarbon deposits

Abstract: A method of extracting hydrocarbons in situ from an underground hydrocarbon deposit such as oil shale. A selected part of the deposit is heated by one or more electrical induction coils arranged in a quasi-toroidal configuration to temperatures high enough to drive off hydrocarbon fractions as gases or vapors, which are then collected and utilized in surface operations or recovered for transportation or temporary storage. The deposit may optionally be heated through a coking and cracking stage. Any remaining hydrocarbons may be burned in situ and the combustion gases utilized for energy. Steam may be obtained by injecting water into the heated shale after extraction of the hydrocarbons.

Energy and Land Constraints in Food Protein Production

Abstract: This year the world population is expected to reach 4 billion and for the year 2000 the projected figure is 7 billion (1). Reduction of the death rates through effective public health measures without a concurrent reduction of birthrates is considered one of the prime causes of the rapid increase in population numbers (2, 3). Because birthrates and family planning are intimately interwoven with the social systems and cultures of individual nations, population control does not immediately follow a fall in the death rate. History suggests that population control occurs because of numerous factors, including social and economic change (3, 4). Obviously, the rapid growth of the human population is resulting in an increased demand for food (1, 5, 6). Experience has shown that augmenting food supplies is not as easy as controlling disease (1, 7). Assuming the figures that suggest an estimated half-billion people are at present protein-calorie malnourished (8, 9) are correct, then great concern is justified about our ability to provide adequate food for the increasing numbers of people that are projected for the future. An integral part of the population-food equation is the use of fossil energy. Energy is consumed in most food and fiber production, in public health activities, and in most endeavors to improve the quality of human life. As we prepare for the future with its rapidly growing world population, concern has been expressed about the limited energy and land resources that are available to increase food production, especially food protein production. In this article we analyze the energy and land demands for both animal and vegetable protein production in the United States, and then examine world food supply as it relates directly to world population density, dietary standards, and food production technology.

Neurologic manifestations of diabetic comas: Correlation with biochemical alterations in the brain

Abstract: Coma and other neurologic abnormalities are present in patients with either diabetic ketoacidosis (DKA) or nonketotic coma (NKC), and the cause of such phenomena are not known. Patients with NKC also manifest seizures and focal neurologic changes. Treatment of diabetic coma with insulin may induce cerebral edema by as yet undefined mechanism(s). In patients with DKA, cerebral oxygen utilization is impaired, and there is hyperviscosity of the blood. A substantial part of the brain's energy source is derived from ketones, which in themselves can depress sensorium. Extracellular hyperosomolality is present, which may also contribute to the genesis of coma. In addition, most ketoacidotic patients have associated medical conditions, which may further impair consciousness. Biochemical changes in the brains of animals with DKA include impairment of both phosphofructokinase activity and pyruvate oxidation, and accumulation of citrate. The net effect upon sensorium in ketoacidotic patients probably represents the interaction of most of the above factors and differs markedly among individuals. Patients with NKC manifest not only depression of sensorium, but also focal motor seizures, hemiparesis, and other neurologic changes, such as aphasia, hypereflexia, sensory defects, autonomic changes, and brainstem dysfunction. Most of the aforementioned changes revert to normal after correction of hyperosomolality. Gamma amino butyric acid, which has been shown to elevate the seizure threshold, is normal in brains of ketoacidotic animals, but may be low in nonketotic coma. Also, hyperosomolality per se may produce seizures. Cerebral edema may complicate the treatment of either DKA or NKC. The available experimental evidence suggests that many of the commonly held theories for the production of such brain swelling probably do not occur. There is no breakdown of the sodium pump, sorbitol or fructose do not accumulate in brain, and brain glucose is only about 25 percent of that in plasma; Cerebral edema is probably produced largely by a direct action of insulin on brain at a time when plasma glucose is approaching normal values. Cerebral edema can thus theoretically be avoided by stopping insulin when plasma glucose has been lowered to values approaching normal.

Adenylate energy charge in Saccharomyces cerevisiae during starvation.

Abstract: Bakers' yeast cells, Saccharomyces cerevisiae, if grown aerobically on ethanol or if grown aerobically on glucose and allowed to pass into stationary phase, with utilization of accumulated ethanol, maintain a normal value (0.8 to 0.9) of the adenylate energy charge during prolonged starvation. In contrast, cells grown anaerobically on glucose and cells in the early stages of aerobic growth on glucose exhibit a rapid decrease of energy charge if transferred to medium lacking on energy source. These results suggest that functional mitochondria or enzymes of balance of adenine nucleotides during starvation. Yeast cells remain viable at energy charge values below 0.1, in marked contrast to results previously obtained with Escherichia coli. In other respects, the engery charge responses of yeast to starvation and refeeding are generally similar to those previously reported for E. coli.

Selectively ventable food package and micro-wave shielding device

Abstract: A frozen or refrigerated precooked meal formed from a number of food components is packaged in a compartmented tray which is transparent to radiant energy such as that from microwave or infrared energy sources. Each of the tray compartments is defined by ridges and side walls formed integrally with the tray and the different component foods of the meal are disposed within selected different tray compartments. A radiation transparent film is secured over the tray and is bonded to the upper edge of the tray side wall and ridges to seal each compartment. Selected areas of the seals between the film and portions of the ridges and/or tray side walls are weakened so that they may rupture in response to excessive water vapor pressure build up to enable the water vapor to escape. The sealed food tray may be placed in a specially formed shielding box which controls the quantity of radiation to which each of the food components are exposed within a given time.

Studies on the nutrition of marine flatfish. The metabolism of glucose by plaice (Pleuronectes platessa) and the effect of dietary energy source on protein utilization in plaice.

Abstract: 1. The effects of dietary energy level and dietary energy source on protein utilization by plaice (Pleuronectes platessa) were examined by giving diets containing 400 g crude protein/kg to nine groups of fish. Five of these diets contained only lipid as a source of energy (in addition to protein) and their energy contents were varied by increasing the lipid level in a step-wise manner from 56 to 176 g/kg. The remaining four diets contained both lipid and carbohydrate (glucose plus dextrin) together as energy sources: two levels of carbohydrate (100 and 200 g/kg) being used at each of two (56 and 86 g/kg) lipid levels. 2. Weight gains of plaice given the diets containing only lipid as an energy source did not differ significantly from each other. Weight gains of plaice given diets containing carbohydrate as well as protein and lipid were superior to those given diets lacking carbohydrate. 3. Values obtained for protein efficiency ratio (PER) and net protein utilization (NPU) increased with increasing dietary energy level in both those fish given the diets containing carbohydrate and those given diets lacking it. Both PER and NPU values were greater for plaice given diets containing carbohydrate than for fish diets without carbohydrate even when the total energy content of the diets was approximately the same. 4. Liver glycogen levels were significantly higher in plaice given diets containing 200 g carbohydrate/kg than in plaice given diets without carbohydrate. Blood glucose levels and hepatic hexokinase (EC 2-7-1-1) levels were not significantly different in plaice given these diets. No glucokinase (EC 2-7-2-2) was detected in plaice given either diet. 5. The metabolic fate of glucose carbon in plaice was investigated by injecting the fish intraperitoneally with [U-14C] glucose and examining, 18 h afterwards the distribution of radioactivity in different biochemical fractions from the fish. 6. Glucose was respired much less rapidly in the carnivorous plaice, irrespective of dietary treatment, than in omnivorous mammals (mouse and rat). The rate of production of 14CO2 from (U-14C) glucose by plaice given diets containing carbohydrate was not significantly greater than that by plaice given diets lacking carbohydrate. 7. More glucose was incorporated into liver glycogen when plaice were given carbohydrate in their food than when it was absent. Otherwise no differences were apparent in the fate of glucose C by plaice which could be related to the diets used. 8. No mortalities occurred nor was any histopathology observed in the plaice as a consequence of the inclusion of carbohydrate in the food.

Apparatus for sensing and transmitting a pacemaker's stimulating pulse

Abstract: Apparatus is disclosed for sensing and transmitting the stimulating pulse of an implanted pacemaker over readily available, low-bandwidth transmission media to a remote receiver capable of measuring the pulse width to provide an indication of the condition of the pacemaker energy source, e.g. a battery. In particular, the sensing and transmitting apparatus detects the electrical activity, e.g. the EKG, of a patient through attached electrodes and modulates a carrier or tone of a suitable frequency to be transmitted over the low-bandwidth transmission medium to the receiver, along with a pulse signal multiplied by a selected, fixed factor dependent upon the carrier frequency of the signal and the other information to be transmitted to the receiver. Illustratively, a factor in the range of 30-50 is selected where it is desired to transmit the pulse width of the pacemaker stimulating pulse along with an EKG, to a receiver to be displayed in a manner to permit evaluation of the EKG and of the width of the stimulating pulse. Typically, the patient in which the pacemaker is implanted has a transmitter for transmitting the aforementioned data to a receiver located in the doctor's office, clinic or hospital, whereby a regular check of the pacemaker's energy source may be made by the patient's doctor.

Phycobilisomes: Light-Harvesting Pigment Complexes

Abstract: Phycobilisomes, as a light-harvesting sytem, appear to be organized for maximum energy transfer, with chlorophyll of the lamellae the final acceptor. Phycobilisomes were first observed by electron microscopy, and the suggestion was made that they are sites of phycobiliproteins. The shape of the phycobilisomes may be determined by the predominant phycobiliproteins present, and their size is quite constant with a diameter of about 40 nm which is about the width of two ribosomes. The algae commit a large part of their resources to phycobilin production. Phycobiliproteins can account for as much as 24% of the dry weight of blue-green algal cells and 40% of the total soluble protein. Most, if not all, of this is contained in phycobilisomes. Energy absorbed by phycobiliproteins can be transferred to chlorophyll with a high degree of efficiency, approaching 80 to 90%. Energy transfer in phycobilisomes is expected to progress from phycoerythrin to phycocyanin to allophycocyanin and eventually to chlorophyll. Evidence obtained from dissociation studies and electron microscopy, has made it possible to suggest a phycobilisome model. For efficient energy transfer, the most logical arrangement of the phycobiliproteins would be to have them in the order of the transfer events. In this arrangement, allophycocyanin wouldmore » be nearest to the photosynthetic membranes, followed by phycocyanin toward the outside. Phycoerythrin would form the outermost layer. Two of the most crucial problems yet to be investigated involve the nature of the attachment site of the phycobilisome to the membrane and the physical relationship of phycobilisomes to the photosynthetic reaction centers. (CAJ)« less

Methylamine and ammonia transport in Saccharomyces cerevisiae.

Abstract: Methylamine (methylammonium ion) entered Saccharomyces cerevisiae X2180-A by means of a specific active transport system. Methylamine uptake was pH dependent (maximum rate between pH 6.0 and 6.5) and temperature dependent (increasing up to 35 C) and required the presence of a fermentable or oxidizable energy source in the growth medium. At 23 C the vmax for methylamine transport was similar 17 nmol/min per mg of cells (dry weight) and the apparent Km was 220 muM. The transport system exhibited maximal activity in ammonia-grown cells and was repressed 60 to 70 percent when glutamine or asparagine was added to the growth medium. There was no significant derepression of the transport system during nitrogen starvation. Ammonia (ammonium ion) was a strong competitive inhibitor of methylamine uptake, whereas other amines inhibited to a much lesser extent. Mutants selected on the basis of their reduced ability to transport methylamine (Mea-R) simultaneously exhibited a decreased ability to transport ammonia.

DRIVING FORCES OF AMINO ACID TRANSPORT IN ANIMAL CELLSfn1

Abstract: Our observations on the response of TPP+ uptake into K+-depleted cells on the extracellular K+ concentration and on the addition of ouabain and amino acid appear to provide suggestive evidence of, or are at least consistent with, the operation of a powerful, K+-activated electrogenic pump. They are also consistent with the assumption that in these K+-depleted cells the active uptake of amino acid energized by the electric PD presumably generated by this electrogenic pump. It follows that an energy source other than the electrochemical potential gradient of Na+ ions need not be invoked to explain active amino acid transport with inverted Na+ and K+ distribution. In the presence of an electrogenic cation pump one should expect that owing to the activity of this pump the electrical PD is raised under these conditions to a value outweighing the opposed chemical potential gradient of Na+. The experimental evidence so far available is clearly consistent with such an assumption.

A national energy policy

Abstract: The basic guidelines for a national energy policy are outlined by Rep. Mike McCormack of Washington. Among his foremost criteria for the formation of this type of policy is that it must be based on the best scientific and engineering information available. Other factors that must be included are conservation measures, a higher standard of living, energy self sufficiency, ultimate dependence upon non-polluting energy sources, and a balance among environmental protection, and a stable economic system. The Congressman points out the folly of relying solely on solutions such as solar energy to deal with the problem since R&D programs such as those will not be ready for implementation until the end of the century. To answer immediate demands more practical measures must be taken such as new technology for drilling and exploring for oil and gas, and improved methods of coal mining and transporting coal. Nuclear energy is another source available at the present time of which we must make the most. Although the hazards of nuclear radiation have been widely publicized, the actual statistics do not warrant this excessive fear. Ideas for the containment of nuclear waste have also been offered. In summary, Rep. McCormack states that the U.S. is in a good position to move ahead now with aggressive programs for the future in solar, geothermal, and nuclear fusion energy. However, since these are long-range goals, present needs cannot be neglected. The challenge today is to develop a policy that will maintain the balance between simultaneously satisfying energy needs and conserving resources, protecting the environment, and preserving a balanced economy.

Nitrate uptake in marine phytoplankton: Energy sources and the interaction with carbon fixation

Abstract: Field studies of whole natural phytoplankton communities from Knight Inlet, B. C., Canada and laboratory cultures of the diatom Skeletonema costatum indicate inorganic carbon fixation may be temporarily suppressed following 10 to 15% enrichment with NO 3 - or NH 4 + . (This effect is suggested to be due to competition between inorganic carbon and nitrogen for adenosine triphosphate (ATP), and is reduced when chlorophyll a is increased intracellularly after 6 to 8 h.) Results imply that the source of ATP for nitrate uptake is primarily from Photosystem I (cyclic photophosphorylation) in the presence of light. It would appear that a transient nutrient-adaptive response occurs upon addition of extracellular nitrogen.

Gluconeogenesis in arctic ground squirrels between periods of hibernation.

Abstract: The hibernation season in the arctic ground squirrel (Citellus undulatus) is broken into 8- to 18- day cycles by short homeothermal periods during which the carboydrate reserves depleted during hibernation are replenished. This study follows a number of metabolities in tissues and body fluids to assess the sources for reconstitution of the glucose reserves: lactate, urea, ammonia, free fatty acid, glycerol, triglyceride, and glucose in plasma; glycogen in liver and muscle; and urea and ammonia nitrogen in urine. Fat is the major energy source during both homeothermal and heterothermal periods, the contribution from glucose being limited to glycolysis. Reconstitution of glycogen is accomplished prior to reentry through maximal use of substrates from all sources including glycolysis, fat, and protein metabolism. Of the new gluconeogenic substrate, one-fourth is supplied from protein and three-fourths from fat.

Nature of the determinant responsible for the adhesion of lactobacilli to chicken crop epithelial cells.

Abstract: SUMMARY: Using an in vitro method, some factors affecting the attachment of a strain of lactobacillus to chicken crop epithelial cells have been studied. Time of contact beyond 10 min, pH value, age or growth temperature of the bacterial culture, or nature of the energy source in the growth medium had little or no effect on attachment. Heating to 100 °C for 10 min, or treatment with EDTA or surface active compounds was also without effect. Treatment with sodium periodate markedly decreased adhesion, proteolytic enzymes had a smaller effect but wheat germ lipase was completely inactive. The pronounced inhibition of adhesion periodate suggested the involvement of carbohydrate. However, enzymes known to attack carbohydrate substrates were inactive in reducing adhesion. Concanavalin A, which binds specifically to certain sugar residues, reduced attachment. It is suggested that these concanavalin A receptors on the lactobacillus are responsible for its attachment to crop epithelial cells.

Microbial metabolism of the pyridine ring. Metabolic pathways of pyridine biodegradation by soil bacteria.

Abstract: 1. Two bacteria, a Bacillus sp. and a Nocardia sp. (strain Z1) were isolated from soil by enrichment with 0.1 percent (v/v) pyridine and grew rapidly on this compound as sole C, N and energy source. The monohydroxypyridines, tetrahydropyridine, piperidine and some other analogues were not utilized for growth or oxidized by washed suspensions of either bacterium. 2. Cell-free extracts were unable to metabolize pyridine even after supplementation with a variety of cofactors or protecting agents. Treatment of cells with toluene led to rapid loss of the ability to oxidize pyridine. 3. In the presence of 10mM-semicarbazide at pH 6.0, Nocardia Z1 accumulated a semialdehyde idenditied as its 2,4-dinitrophenylhydrazone by chromatography, mixed melting point, mass spectrometry and isotope trapping from [2,6(-14)C]pyridine as glutarate semialdehyde. 4. Extracts of this bacterium prepared from cells grown with pyridine or exposed to the gratuitous inducer 2-picoline, contained high activities of a specific glutarate semialdehyde dehydrogenase. 5. Cells grown with pyridine or glutarate also contained a glutaric dialdehyde dehydrogenase, an acyl-CoA synthetase and elevated amounts of isocitrate lyase but no glutaryl-CoA dehydrogenase. 6. Bacillus 4 accumulated in the presence of 10mM-semicarbazide several acidic carbonyl compounds from pyridine among which was succinate semialdehyde. Extracts of this bacillus after growth of the cells with pyridine contained an inducible succinate semialdehyde dehydrogenase in amounts at least 50-fold over those found in succinate-grown cells. 7. Two mutants of this bacillus, selected for their inability to grow on pyridine were deficient in succinate semialdehyde dehydrogenase. 8. In the presence of 0.2mM-KCN, washed suspensions of Bacillus 4 accumulated formate and possibly formamide from pyridine. The use of [14C]pyridine showed that formate was derived from C-2 of the pyridine ring. 9. The organism had a specific formamide amidohydrolase cleaving formamide quantitatively to formate and NH3. 10. Formate was further oxidized by the particle fraction. There was no soluble formate dehydrogenase in extracts.

Human lymphocyte surface immunoglobulin capping. Normal characteristics and anomalous behavior of chronic lymphocytic leukemic lymphocytes.

Abstract: The phenomenon of redistribution of surface membrane immunoglobulin (Ig) components (capping) has been well described in mouse lymphoid cells. The characteristics of this process in human lymphocytes are less clear. This study characterizes the phenomenon of surface membrane Ig redistribution of normal and chronic lymphocytic leukemia (CLL) lymphocytes with the use of fluoroscein-labeled anti-Ig sera. Normal lymphocytes underwent rapid cap formation after incubation with anti-Ig serum in the cold and subsequent rewarming. The morphology was characteristic with aggregation over the pole of the cell opposite the nucleus and over the uropod when present. The process was energy dependent but independent of protein synthesis, and could be inhibited by vincristine, vinblastine, and colchicine but not by cytochalasin B. CLL cells, on the other hand, though showing fluorescent complex aggregation on the surface, rarely demonstrated unidirectional movement of these aggregates to form a cap. Cap formation in these cells could not be stimulated by supplementing the energy source or protein concentration of the medium nor by adding glutamic acid which could partially reverse the vincristine and vinblastine inhibition of normal capping. The failure of agents which inhibit motility to inhibit capping of the normal lymphocytes suggests that active locomotion is not a direct prerequisite for capping. The results also suggest the involvement of microtubules in normal capping and the possibility that abnormal membrane structure or microtubular function could explain the failure of CLL cells to behave normally in this regard. The role of this cellular defect in the immune deficiencies exhibited by many patients with CLL, however, is not established.

Process and apparatus for evaporating and heating liquified natural gas

Abstract: The liquified natural gas is passed in heat exchange relation with a flow of air in order to use the heat energy in the air to heat and vaporize the liquified natural gas. The resulting cooled air is then used as the input to an open gas turbine plant. This, in turn, increases the efficiency of the turbine plant and an overall conservation of energy effect is produced. In order to avoid freezing of any water vapor in the air, a medium having a lower freezing point than water is mixed into the air flow prior to heat exchange.

Sequential growth of bacteria on crude oil.

Abstract: By modification of the enrichment culture procedure three bacterial strains capable of degrading crude oil in sea water were isolated in pure culture, UP-2, UP-3, and UP-4. Strain UP-2 appears to be highly specialized for growth on crude oil in sea water since it showed strong preference for oil or oil degradation products as substrates for growth, converted 66% of the oil into a form no longer extractable by organic solvents, quantitatively degraded the paraffinic fraction (gas chromatographic analysis), emulsified the oil during exponential growth, and produced 1.6 x 10-8 cells per mg of oil. After exhaustive growth of UP-2 on crude oil the residual oil supported the growth of UP-3 and UP-4, but not a previously isolated oil-degrading bacterium, RAG-1. Strains UP-2, UP-3, and UP-4 grew on RAG-1-degraded oil (specifically depleted of n-alkanes). The growth of UP-3 and UP-4 on UP-2 and RAG-1-degraded oil resulted in the production of new paraffinic compounds as revealed by gas chromatography. When the four strains were grown either together in a mixed culture or sequentially, there was over 75% oil conversion. By plating on selective media, growth of the individual strains was measured kinetically in the reconstituted mixed culture, revealing competition for common growth substances (UP-2 and RAG-1), emhanced die-off (UP-2), and stabilization (UP-4) during the stationary phase.

Decreased rate of glucose utilization by rat brain in vivo after exposure to atmospheres containing high concentrations of CO2.

Abstract: —(1) The effects of exposure of rats to increased atmospheric concentrations of CO2 on brain metabolism in vivo were studied. (2) After 2·5 min exposure to an atmosphere of 20% CO2, the rate of glucose utilization by brain decreased from 0·61 μmol/min per g to 0·32 μmol/min per g and remained between 0·3 and 0·4 μmol/min per g for 60 min, the longest interval studied. O2 utilization, calculated from the arteriovenous difference of O2 across the brain and blood flow, was 3·5 μmol/min per g in controls and was 4·7 μmol/min per g after 5 min in the 20% CO2 atmosphere. (3) The concentrations of glucose, glucose 6-phosphate and aspartate were increased during the first 10 min of CO2 exposure whereas the concentrations of other glycolytic intermediates, tricarboxylic acid cycle intermediates and glutamate were decreased. The amount of endogenous substrate which disappeared during the first 10 min was sufficient, if used to supplement glucose as a fuel, to maintain the O2 consumption at, or slightly above, the control level. Glutamate and lactate were quantitatively the most important energy sources. (4) The mechanism whereby‘CO2 decreased the rate of glucose utilization is uncertain. The initial rise in glucose 6-phosphate and fall in fructose 1,6-diphosphate concentrations suggested that an inhibition of phosphofructokinase was responsible. However, after 60 min in 20% CO2, the concentrations of both of these metabolites returned to normal while the rate of glucose utilization remained depressed.

atmospheric heating by solar EUV radiation

Abstract: A diurnal model of the mid-latitude ionospheric R region is used to calculate the diurnal variation of the neutral gas heating rates and neutral gas heating efficiency for conditions similar to those over Millstone Hill on March 23-24, 1970. The calculations show that the absorbed solar EUV (wavelength less than or equal to 1025 A) energy is almost equally split between photoelectrons and ion pair production. Photoelectrons heat the ambient electron gas by Coulomb collisions and by the quenching of certain excited ion species, whereas the ion gas is primarily heated by collisions with hot electrons and by chemical reactions. Heating processes above 300 km, between 170 and 300 km, and below 170 km are identified.

Source reconciliation of atmospheric hydrocarbons

Abstract: Source reconciliation is a procedure for determining the source composition of complex hydrocarbon mixtures such as occur in the atmosphere. Source profiles were determined for the major sources of atmospheric hydrocarbons in the Los Angeles area including automotive exhaust, gasoline, commercial natural gas and geogenic natural gas. Atmospheric hydrocarbon profiles were determined at three sites during the summer of 1973. Multivariate regression analysis was used to determine the optimum source configuration for each atmospheric sample. By this method, the average distribution of nonmethane hydrocarbon emissions from the major sources was found to be: automotive exhaust 47%; gasoline, 31%; commercial natural gas, 8%; and geogenic natural gas, 14%.