Showing papers on "Particulates published in 1984"

Geochemistry of organic matter in the ocean

Abstract: Abbreviations.- 1. Sources of Organic Matter in the Ocean.- 1.1 Primary Production of Organic Matter.- 1.1.1 Phytoplankton.- 1.1.2 Phytobenthos.- 1.1.3 Bacterial Chemosynthesis.- 1.2 Input of Allochthonous Organic Matter.- 1.2.1 River and Subterranean Runoff.- 1.2.2 Eolian Transfer.- 1.2.3 The Material of Glacial and Wave Abrasion.- 1.2.4 Other Sources.- 1.2.5 Relationship of the Various Sources and Forms of Supply.- 2. Carbon of Dissolved Organic Matter in the Ocean.- 2.1 Total Quantity.- 2.2 Time of Residence.- 2.3 Distribution Patterns.- 3. Carbon of Particulate Organic Matter.- 3.1 POC Distribution from Separation Data.- 3.2 POC Distribution from Filtration and Sediment Traps Data.- 3.3 POC in Dry Matter of Suspended Material.- 3.4 Relationship Between POC and DOC.- 3.5 Living Organic Matter in Suspended Material.- 3.6 Total Quantity and Residence Time of Particulate Organic Matter in the Ocean.- 3.7 Organic Matter Morphology.- 3.8 Supply of Organic Matter in Ocean Depths and Ocean Floor.- 3.8.1 Trophic System and the Passive Settling of Particles.- 3.8.2 Transition of Dissolved Organic Matter into the Particulate Form.- 3.8.3 Active Transport of Organic Matter by Migrating Animals.- 4. Organic Carbon in Late Quarternary Sediments of Seas and Oceans.- 4.1 Morphology of Non-Living Organic Matter in Recent Sediments.- 4.1.1 Organic Detritus and Aggregates.- 4.1.2 Terrestrial Plant Remains and Macrophytes. Pollen Grains and Spores.- 4.1.3 Organic Matter of Biogenic Calcareous and Siliceous Materials.- 4.1.4 Ichtyofaunal Bone Remains.- 4.1.5 Organic Matter Associated with Clay Materials.- 4.1.6 Organic Matter in Igneous Rocks.- 4.1.7 Other Forms of Organic Matter.- 4.2 Principles Governing the Distribution of Organic Carbon in Bottom Sediments.- 4.2.1 Regularities of Regional Distribution in the Upper Sedimentary Layer.- 4.2.2 Organic Carbon in Various Genetic Types of Sediments in the Pacific and Atlantic Oceans.- 4.2.3 Organic Carbon Distribution in the Late-Quarternary Sediments of the Pacific Ocean.- 4.3 Organic Carbon Distribution in the Size-Fractions of Sediments: Relation Between Organic Carbon and CaCO3 and SiO2(amorph).- 4.4 The Absolute Masses of Organic Carbon in the Sediments.- 4.4.1 A Concise History of the Problem.- 4.4.2 The Rate of Organic Carbon Accumulation in Bottom Sediments.- 4.4.3 The Amount of Organic Carbon and Its Fossilization Coefficients in Various Zones of the Ocean.- 5. Nitrogen and Phosphorus in the Process of Sedimentogenesis.- 5.1 Nitrogen and the Nitrogen-Carbon Ratio.- 5.1.1 Nitrogen in Marine Organisms. Regeneration of Nitrogen.- 5.1.2 Organic Nitrogen in Sea Waters and the Particulate Fraction.- 5.1.3 Nitrogen in Bottom Sediments and Interstitial Waters.- 5.2 Phosphorus and the Phosphorus-Carbon Ratio.- 5.2.1 Phosphorus in Marine Organisms. Regeneration of Phosphorus.- 5.2.2 Organic Phosphorus in Sea Waters and the Suspended Material.- 5.2.3 Phosphorus in Bottom Sediments.- 5.3 Certain Features of the Cycling of Nitrogen and Phosphorus During Sedimentogenesis.- 6. Proteinaceous Compounds and Amino Acids.- 7. Carbohydrates.- 7.1 Carbohydrates in the Major Producers and Consumers of Organic Matter in the Ocean.- 7.2 Carbohydrates in Sea Waters.- 7.3 Carbohydrates in the Suspended Matter.- 7.4 Carbohydrates in Bottom Sediments.- 7.4.1 The Content and Composition of the Carbohydrates in the Sediments of the Surface Layer.- 7.4.2 Carbohydrates in Bottom Sediment Cores.- 7.4.3 Carbohydrate Compounds in Interstitial Waters.- 8. Chemical Transformations of Lipids During Sedimentogenesis.- 8.1 Lipids of Marine Organisms.- 8.2 Sea Water Lipids.- 8.3 Lipids in Suspended Material.- 8.3.1 The Quantitative Distribution of Particulate Lipids in the Ocean.- 8.3.2 The Composition of Particulate Lipids and Its Variations in the Mass of Ocean Waters.- 8.3.3 Comparative Characteristics of Particulate and Dissolved Lipids.- 8.4 Lipids in Bottom Sediments.- 8.4.1 Regularities in the Distribution of Lipids in Bottom Sediments.- 8.4.2 Lipids in the Interstitial Water.- 8.4.3 The Composition of Lipids in Bottom Sediments.- 8.5 Transformation of Lipids in Sedimentogenesis.- 9. Specific Organic Compounds.- 9.1 Humic Substances of Sea Water.- 9.2 Distribution of Humic Acids and Residual Organic Matter Humins in Suspended Matter and in Bottom Sediments.- 9.3 Elementary Composition.- 9.4 Molecular Weight Distribution.- 9.5 Amino Acid Composition. The Content of Carbohydrates and Functional Groups.- 9.6 The Composition of Destructive Oxidation Products.- 9.7 The Origin of Humic Acids in Bottom Sediments.- Conclusion.- References.

Spectral properties of ice‐particulate mixtures and implications for remote sensing: 1. Intimate mixtures

Abstract: From laboratory spectra of many ice-particulate mixtures with high, medium, and low albedo particulates, the band depths, continuum reflectance, and ratio of band depth to continuum reflectance are derived as a function of the logarithm of thef particulate weight fraction in the sample. Ice band depths are dependent on the particulate albedo, and increase with smaller weight fractions of particulates until the bands saturate and their depths decrease. While the continuum reflectance is a complex function of the particulate albedo and wavelength of light, the band depth-to-continuum reflectance ratios appear independent of particulate albedo in such a fashion that, for a given grain size of particulate, a calibration curve to the abundance of ice and particulates is derived. Theoretically produced frost spectra show similar curves of growth for band depth, continuum reflectance, and corresponding ratio vs the photon mean optical path length.

Spatial and temporal coupling of nutrient inputs to estuarine primary production: the role of particulate transport and decomposition

Abstract: Spatial and temporal aspects of the coupling of nutrient inputs to estuarine primary production are discussed in terms of formation, transport and decomposition of particulate material in the Patuxent River estuary. Mixing diagrams of dissolved and particulate nitrogen and phosphorus (DIN, PN, DIP, PP) versus salinity indicate rapid removal of DIN and DIP with parallel formation of PN and PP in the slightly brackish (0-5%0) region. However, plankton production (per m2) tends to be inversely related to salinity between 0 and 10%0. While most of the annual nutrient inputs to the Patuxent occur between December and April, peak plankton production occurs in the summer. Deposition and resuspension of particulate substances in this system are dynamic processes which decrease in a seaward direction. Regeneration of DIN and DIP from particulate decomposition in the sediments similarly decreases toward the estuary's mouth; however, highest rates are in the 5-100/00 region. Temporal patterns of benthic regeneration and plankton production are congruent (being generally related to temperature), and rates of sediment NIL, + recycling represent about 60-80% of the plankton assimilative demand in the 5-100/00 region. On the basis of these observations we propose a conceptual model in which annual inputs of dissolved nutrients from runoff are converted into particulate forms which are gradually transported seaward through cycles of deposition and resuspension. As temperatures rise in the summer these particulates are decomposed, releasing dissolved nutrients to the euphotic zone where they support the major annual blooms of plankton. By comparing these patterns for the Patuxent with those reported for other estuaries, it is suggested that this model may be relatively general for many coastal

Handbook of air pollution technology

Abstract: This handbook presents essential principles design methods, examples data, and guides to more information on air pollution and its control. Topics considered include: effects of air pollutants on plants; effects of air pollutants on the atmosphere; particulate pollutant characteristics; control of gases by combustion; particle particle control by scrubbing; control of particulates by electrostatic precipitation; control costs; unconventional fuels; emission control in internal combustion engines; source control--Ferrous Metallurgy; source control--mineral processing; source control--chemical; source control feed; control of fugitive emissions; sampling and analysis of ambient gases; plume opacity; atmospheric dispersion; air pollution standards and regulation; and information resources.

Transportation of water, particulate and dissolved organic and inorganic matter between a salt marsh and the Ems-Dollard estuary, The Netherlands

Abstract: Transport processes were studied in a gully between a saltmarsh and an estuary. After storm tides, ebb currents in the gully reached high values. It is concluded that particulate matter (both obganic and inorganic) are imported into the marsh. Coarse organic debris is exported during storm tides, but this amount is low when compared with the primary production on the marsh. Exports are shown for dissolved organic carbon, ammonia, phosphate and silica, while nitrate and possibly nitrite are imported. Therefore, it seems warranted to conclude that the organic matter producedin situ and imported is mineralized in the marsh.

Fuel Composition Effects on Heavy-Duty Diesel Particulate Emissions

Abstract: The effects of fuel composition on diesel exhaust particulate emissions have been studied at several steady-state operating conditions using a heavy-duty laboratory engine. Particulate emissions were influenced by three primary fuel factors: sulfur content, aromatics content, and volatility. At all but lightly loaded operating conditions, fuel sulfur was the dominant fuel factor in particulate formation. Fuel sulfur affects particulate emissions primarily by formation of sulfate (as sulfuric acid) and associated "bound" water and, to a lesser degree, by increasing the amount of soluble organic material collected. Aromatics and volatility influence the amount of carbonaceous material formed. Five polynuclear aromatic hydrocarbon (PAH) compounds were measured in the soluble organic fraction. Engine operating conditions greatly affected PAH levels; however, no strong influence of fuel composition on PAH concentrations was observed in the normal range of No. 1-No. 2 diesel fuels.

Transfer of particulate organic carbon and nitrogen from the Yangtze River to the ocean

Abstract: The Yangtze River transports 12 million tons of particulate organic carbon (POC) to the oceans annually, with a computed yield of 6 t km/sup -2/ of drainage basin area. Concentrations of POC can exceed 80 mg/L in near bottom waters but generally range from 4 to 40 mg/L throughout the water column. Most POC percentages (in suspended matter) vary from 1.7 to 4.0 percent, the percentage decreasing with increasing suspended matter concentration although at lesser gradient than that predicted by Meybeck. The divergence from Meybeck's world curve may be related to the high degree of human activity in the Yangtze drainage basin, or it may reflect lack of data from large rivers with high suspended loads. If the Yangtze values are representative of other turbid Asian rivers, present global estimates of fluvially-derived POC may be as much as 50% too low. 17 references, 8 figures, 1 table.

Sedimentation and benthic mineralization of organic detritus in a Norwegian fjord

Abstract: The supply of particulate material to the sea-bed as well as the oxygen consumption and the redox potential of the sea-bed were measured during a one-year period (1979/1980) at 60 and 90 m depth in the inner part of a west Norwegian fjord, Fanafjorden. At both sites, uniform sedimentation rates of total particulate material (825 and 885 g m-2 yr-1, respectively) and particulate inorganic material (576 and 616 g m-2 yr-1, respectively) were found. The sedimentation rates of particulate organic carbon (96 and 107 g m-2 yr-1, respectively) and particulate organic nitrogen (10 and 12 g m-2 yr-1, respectively) were low in winter, higher in summer and autumn, with maxima in May/June, reflecting similar maxima in the phytoplankton biomass in the area, with 6 to 8 wk delay. The oxygen consumption of the sea-floor was lowest in winter/spring and highest in summer. Thirtytwo and 38 g C m-2 yr-1 (respiration quotient=0.85) were metabolized by the sediment at 60 and 90 m, respectively. The simultaneous measurements of sedimentation rates and sediment oxygen uptake throughout a whole year demonstrated that the benthic mineralization is governed by the sedimentation over a longer time-scale, but that seasonal imbalances do occur. A box-model of the flux of particulate organic carbon to the sediment surface is presented, and includes the relevant processes and some quantitative estimates.

The role of flocculation in the filtering of particulate matter in estuaries

Abstract: The structuring of suspended particulate matter in estuaries into flocculated settling entities is described and discussed. A hierarchy of three particle distribution types is described: In situ distributions contain abundant large low density fragile aggregates(macro-flocs) with high settling rates, the formation of which is promoted by low turbulence and high particulate concentrations. During periods of high currents in nature and during shipboard and laboratory sample handling, these macro-flocs break up into more stable distributions of smaller flocs which are the basic building blocs of the larger units. Laboratory oxidation of organic matter and disaggregation of aggregates allow the size analysis of individual single mineral grain distributions for purposes of direct comparison between bottom and suspended sediment spectra. The constituent grain-size distribution of the inorganic component of a floc replicates the grain size of the suspension as a whole. The diverse grain size and chemical nature of the organic matter makes its flocculation kinetics more complicated. Past laboratory experiments have indicated the existence of organic-inorganic proportions optimum for flocculation. This is substantiated by ash-loss data from three estuaries with different relative inputs of organic and inorganic matter. The particulate matter in each was dominated by similar organic-inorganic proportions (65-75% organic matter by volume) indicating that the component in excess of this value had been preferentially exported from the estuary. Settling of suspended sediment as macro-flocs and near bottom break-up and resuspension of floc fragments control the very dynamic equilibrium between particle trapping and particle flushing in estuaries.

Particulate analysis of light duty diesel engines (IDI&DI) with particular reference to the lube oil particulate fraction

Abstract: Particulate mass emissions (US-EPA FTP75) of a variety of light duty diesel (IDI) production vehicles have been analysed for their content of organic insoluble and organic soluble fractions The latter was further separated into lube oil and fuel particulate fractions by a gas chromatographic method which is described in the paper This has provided the information to establish a database on the relative contributions of organic solubles and lube oil to both total particulates and total hydrocarbon (HC) emissions As a result a target minimum lube oil particulate emission level has been defined to act as a guide line in engine development to minimize the contribution of the lube oil to total particulate matter Additionally, HC and the various particulate fractions of IDI and DI high speed diesel engines are compared under steady state and transient operating conditions and their relative significance indicated Finally, the effect of engine design parameters mainly controlling lube oil particulates is quantified

The sea-surface microlayer: phytoneuston productivity and effects of atmospheric particulate matter

Abstract: The sea-surface microlayer, the upper 50 μm of the ocean surface, provides a habitat for an important biota (the neuston), an interface for exchange of gases between the atmosphere and oceans and a site for deposition of anthropogenic metals and other materials from the atmosphere. Several recent studies have suggested that biochemical processes, including photosynthesis, in the microlayer are inhibited relative to the bulk seawater. We compared the biomass, species composition and productivity of phytoneuston to that of phytoplankton in Sequim Bay, Washington State, USA. Mean enrichment ratios (microlayer: bulk water concentrations) for bacteria, microalgae, chlorophyll pigments and photosynthesis (estimated gross) were 2 444, 380, 12 and 40, respectively. Compared to the bulk water, the microlayer had a unique assemblage of microalgae with a higher concentration of chlorophyll c. When exposed to high light intensities (summer) or metalrich urban atmospheric particulate matter, radiocarbonmeasured photosynthesis was lower in phytoneuston than in phytoplankton. Deposition of atmospheric particulate matter at rates similar to those occurring in urban coastal areas resulted in a significant (P<0.01) reduction in radiocarbon-measured photosynthesis in the sea-surface microlayer. These apparent decreases in photosynthesis are believed to result from the extracellular release of 14C as glycolate or other soluble compounds and may not reflect a true decrease in gross primary productivity in the microlayer. Further measurements of the degree of extracellular carbon release will be necessary to quantify gross photosynthetic rates in the microlayer.

Suspended particulate organic material from hydrothermal vent waters at 21° N

Abstract: Ocean floor spreading centres described recently consist of several sites with chemical and biological features unlike any oceanic sites previously known1–4. The high-pressure and warm-temperature regimes at these sites, coupled with dynamic hydrothermal water circulation, support biological communities that utilize a source of primary production which appears to be non-photosynthetic5. A detailed biochemical analysis of the suspended matter at a biologically-active site has been undertaken, with the goal of describing the relationship between microorganisms, benthic organisms and suspended particulate material within these hydrothermal systems. Suspended particulate matter from warm hydrothermal vent waters (5–38°C) of the East Pacific Rise1–4 (21° N, 106° W) was sampled on the OASIS expedition with an in situ pumping system in April 1982. Particulate organic carbon (POC) and nitrogen (PON) as well as individual organic compound classes from the lipid fraction were analysed to ascertain the sources and composition of the organic matter in this highly productive area. We show here that the particulate organic material (POM) of the vent water was both quantitatively and qualitatively different from the non-vent bottom water. The POC and PON measured within the vent and non-vent waters vary by a factor of 2–5, the higher values being in warm water. The organic matter in the non-vent water was found to be more resistant towards degradation or remineralization than in the vent water, as shown by the C:N ratio and the total lipid:POC ratio. Contributions to the lipid class compounds were assessed using well-known organic compound source biomarkers such as hydrocarbons, fatty alcohols, sterols, triacylglycerols and steryl and wax esters.

Comparison of solvent extraction and thermal-optical carbon analysis methods: application to diesel vehicle exhaust aerosol.

Abstract: Filter samples of particulate emissions from two diesel automobiles were analyzed by solvent extraction with a hot toluene/1-propanol mixture, by thermal-optical carbon analysis, and by X-ray fluorescence analysis On the average, carbon accounted for 83% of the particulate matter, and organic carbon comprised 70% of the extractable mass The ratio of elemental carbon as measured by the thermal-optical technique to unextractable mass was 105 +/- 004 For most of the filters the unextractable mass was predominantly elemental carbon However, for the filters with the largest amounts of unextracted material the elements Fe, S, Al, Si, and Ca were present in significant amounts (03-5% each of the unextractable mass when expressed as oxides) 29 references

The Contribution of Engine Oil to Particulate Exhaust Emissions from Light-Duty, Diesel-Powered Vehicles

Abstract: An apparatus was developed for the determination of the engine oil contribution to both total and extractable particulate exhaust emissions from diesel-powered vehicles during cyclic operation on a chassis dynamometer For the five vehicles tested, the percentage of the total particulate material that was derived from engine oil ranged from 7 to 14% Between 14 and 26% of the total particulate material was extractable with benzene-ethanol (80-20) solvent Oil contributed from 30 to 55% of the extractables in most cases Engine design and oil formulation generally appeared to have only small effects on the oil contribution to the particulate emissions A 1982 model-year vehicle with a 18L engine was an exception, since its oil contribution to the total and especially to the extractable particulate emissions (14 and 95%, respectively) was significantly greater than for any of the other vehicles

Sterenes in suspended particulate matter in the eastern tropical North Pacific

Abstract: Particulate matter in the oceans is operationally partitioned into two pools. Large (≳ 32 µm) particles, such as zooplankton faecal pellets and marine snow, sink rapidly and dominate the vertical flux of organic matter in the oceans1–4. These relatively rare particles, usually collected in sediment traps, sink at rates of tens to hundreds of metres per day5–8 leading to a significant flux of labile particulate organic matter from sites of production in the euphotic and mesopelagic zones to the deep ocean9–14. Finer (≲ 2 µm) suspended material, on the other hand, dominates the standing stock of particulate matter1. Sinking rates of only a few metres per day for small particles result in long residence times in the water column during which major transformations of the suspended organic matter may occur. Source and transformation processes involving particulate organic matter in seawater and Recent sediments may be traced by studying various classes of specific organic marker compounds, including the steroids9,11,15–18. We report here the apparent production of sterenes (steroidal alkenes) on suspended particulate matter within the oxygen minimum zone in the equatorial Pacific Ocean off central Mexico; this provides further evidence of the importance of water column processes on early stages of the transformation of biogenic sterols to the steranes present in mature sediments.

Multi-chambered air cleaner

Abstract: A multi-chambered air cleaning device is disclosed for removing particulate and other material from air passing through the device, as is a method for removing particulate and other matter from exhaust air. The device includes a front portion for collecting hot exhaust air to be cleaned and vaporizing the same to coagulate particulate matter in the air, and a back portion with a plurality of filters for removing the particulate material as well as other impurities such as gaseous odors. The device is particularly useful to clean air exhausted from a tail pipe connected with an internal combustion engine, and is also useful to clean gases emitted from pipes and/or stacks connected with combustion-type devices such as are commonly found in industrial plants.

Processes using calcined, high surface area, particulate matter, and admixture with other agents

Abstract: This invention is concerned with production and use of high surface area particulate matter by calcining a charge of clay mineral, feldspar, zeolite, coal ash, fly ash, pozzolan or volcanic ash for a time to develop fractures which increase the surface area of the particles. Vacuum calcining decreases the calcining time. The calcined matter desirably has an analysis including: calcium oxide, about 20-40 weight %; aluminum oxide, about 15-35 weight %; and silicon oxide, about 20-40 weight %. The calcined particulate matter can be used in the treatment of impure aqueous materials; the matter is denser than water and sludge settles rapidly and completely. The calcined matter interacts with heavy metal ions to form tightly bound sludge that is nonhazardous for landfill disposal. The calcined matter can be combined with conventual coagulants, flocculants, filter aids, or activated carbon to obtain a multipurpose treating agent. The calcined particulate matter can be combined with exotic waste water treating agents obtaining results not attainable by these exotic agents alone. The exotic agents are borohydride, dialkyldithiocarbamates where alkyl has 1-5 carbon atoms and `carbamate` has alkali metal or ammonium, dithionites, glycine, hydrazine salts, metabisulfites, polygalacturonic acid, water soluble sulfides and sulfites, and cellulose and starch xanthates.

Sulfate accumulation in a sea breeze/land breeze circulation system

Abstract: An atmospheric tracer study using SF_6 was conducted on July 22, 1977, to examine the origin of the high particulate sulfate concentrations observed in coastal Los Angeles County. It was found that the sea breeze/land breeze circulation system in the Los Angeles Basin both increases the retention time for sulfate formation in the marine environment and causes individual air parcels to make multiple passes over large coastal emissions sources. Day-old sulfur oxides emissions advected out to sea by the land breeze at night were estimated to be the largest single contributor to 24-hour average sulfate air quality over land the next day. In contrast, 24-hour average SO_2 concentrations were dominated by fresh emissions from nearby sources. The overall rate of SO_2 transformation to form particulate sulfur oxides along some trajectories that spent a considerable time over the ocean at night probably exceeds the rate that can be explained by known photochemical processes acting during the daylight portion of these trajectories. This suggests that appreciable aerosol formation may occur in a polluted marine environment at night.

Diesel particulate filter system

Abstract: A diesel particulate filter system for treating the exhaust gas of a diesel engine which is small in size and inexpensive. The system includes a particulate filter connected in a gas line from the engine, a burner, including an ignition plug, connected at a point upstream of the particulate filter and which is supplied with fuel, a primary air flow for atomizing the fuel, and a secondary air flow for burning the particulates trapped in the particular filter and which supplies the particulate filter with a hot burning gas produced by the ignition plug. Primary and secondary pumps supply, respectively, the primary and secondary air flows. A single motor drives both the primary and secondary air pumps. The ignition plug and motor are controlled so that when the amount of particulates trapped in the filter exceeds a preset level, the ignition plug and motor are activated to clean the filter by burning the particulates in the burner.