Fine Organic Particles Research Articles

FEATURES OF DIRECT AND ADVANCED DEVELOPMENT OF SCIENCE OF THE DEPARTMENT OF LIFE SAFETY AND ENGINEERING ECOLOGY AT KHARKIV STATE UNIVERSITY OF CIVIL ENGINEERING AND ARCHITECTURE

The global environmental crisis in the mid-twentieth century caused the rapid development of applied fields of ecology, including the doctrine of the environmental security. its nature protection part was mainly provided by technical solutions. This facilitated the opening of the departments of ecology in technical schools and the greening of their specific areas of engineering. The Department of Life Safety and Engineering Ecology at Kharkiv State University of Civil Engineering and Architecture scientifically masters and develops not only the monitoring of technogenically loaded ecosystems, but also the search for technical solutions that reduce this load. The main directions of its work are: ecological safety of biosphere environments and life safety in them; environmental problems of the construction industry, urban development and urban economy, greening of urban development.The most successful and implemented scientific works include the identification of environmental hazards of atmospheric air pollution by the emission of fine particulate organic particles (which are pathogens, allergens and a mediated source of greenhouse gases), the development of technology to protect from them. it has been experimentally proved that ionization reduces the concentration of fine particulate organic particles in atmospheric air to the normatively acceptable level. The most interesting works of another direction include the solution of environmental problems of the sewer systems operation and the video ecology of small architectural forms of this technical field. installations of degassers for purification of gaseous emissions from sewage networks at locations among residential buildings, parks and recreational zones, in areas of the city with historical development created acute visual dis- comfort — video pollution. Design proposals for design solutions to improve the video ecological characteristics of degassing installations and harmonize them with the environment have been developed.

Study of Suspended Impurities Origin and Composition in the Treatment Process of Johkasou System

Johkasou system is widely used in Japan for household wastewater treatment and have played important roles in maintaining the water environment. However, out of the total units used in Gifu Prefecture, about 10% cannot meet the quality requirement for the effluent transparency above 30 degrees. Previous studies have shown clearly that the reason is mainly attributed to suspended impurities that remain in the water after treatment, with more than 96% being consisted of fine particles with sizes of 0.5-1.0 μm. A detailed investigation for identifying the origin and composition of the fine particles is necessary in order to find the approaches to improve the treatment function of the related Johkasou units. The analysis by Flow Cytometry suggested that the organic fine particles could be grouped into bacterial fraction, existed in all tanks of the Johkasou, and non-bacterial fraction that was confirmed mainly existed in anaerobic tanks, thus suggesting the lower transparency of Johkasou's effluent was greatly contributed by the bacterial fraction. PCR-DGGE further identified that some of the bacteria contained in the effluent were originated from the anaerobic tank.

Measurement and density normalisation of acoustic attenuation and backscattering constants of arbitrary suspensions within the Rayleigh scattering regime

The scattering and attenuation of megahertz frequency acoustic backscatter in liquid suspensions, is examined for a range of fine organic and inorganic particles in the Rayleigh regime, 10−4 < ka < 100 (where k is the wavenumber and a the particle radius) which are widely industrially relevant, but with limited existing data. In particular, colloidal latex, mineral titania and barytes sediments, as well as larger glass powders were investigated. A manipulation of the backscatter voltage equation was used to directly measure the sediment attenuation constants, ξ. Decoupling of the combined backscattering-transducer constant, allowing explicit measurement of the backscattering constant, ks, was achieved through calibration of the transducer constant, kt. Additionally, the methodology was streamlined via averaging between a number of intermediate concentrations to reduce data variability. This approach enabled the form function, f, and the corresponding total normalized scattering cross-sections, χ, to be determined for all species. While f and χ are available in the literature for large glass and sand, this methodology allowed extension for the colloidal organic and inorganic particles. Specific gravity normalisation of f collapsed all data onto a single distribution, with the exception of titania, due to scattering complexities associated with agglomeration. There was some additional variation in χ, with measured values of the fine particles up to of magnitude greater than the density-normalised prediction at low ka. Mechanisms accounting for these variations from theory are however analysed, and include viscous attenuation effects, the polydispersity of the particle type and increasing influence of the solvent attenuation. Additionally, thermoacoustic losses appeared to dominate the attenuation behaviour of the organic latex particles. This study demonstrates that particles close to the colloidal regime can be measured successfully with acoustic backscatter, and highlights the great potential of this technique to be applied for in situ or online monitoring purposes in such systems.

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Cover: A bright field transmission electron microscope image of an organic particle (light grey) in a phyllosilicate groundmass from the CR chondrite, GRO 95577. Finer organic particles are also dispersed in the phyllosilicate. Scale bar is 200 nm. For details, see the article by Hitesh Changela et al. in this issue. Image courtesy of Changela et al.

Spectral signature of suspended fine particulate material on light absorption properties of CDOM

Abstract Fine submicron organic particles can represent an important fraction of the dissolved organic matter (DOM) pool in aquatic ecosystems and their optical properties differ from those normally considered dissolved ( n = 1734) from different ecosystems (lakes, streams, sewages and estuaries) were measured on 0.2 μm and GF/F (nominal pore size 0.7 μm) filters. The aims were to evaluate how fine organic particles influence the spectral signature of the DOM pool and to quantify the effects of choice of filter type. In aquatic ecosystems influenced by terrestrial DOM (rivers and lakes), the dissolved fraction (here defined as

Soil-derived organic particles and their effects on the community of culturable microorganisms.

Soil microbial community interacts with a range of particulate material in the soil, consisting of both inorganic and organic compounds with different levels of water solubility. Though sparingly water-soluble and insoluble organic compounds in the soil may affect living organisms, they are difficult to introduce into microbiological media. Their biological activity (i.e., their effect on soil microorganisms) thus has been almost neglected in most of the cultivation assays. To fill this gap, we propose the use of fine organic particles prepared from soil organic matter that are introduced into a laboratory medium where microbial community is cultivated. To this purpose, submicrometer particles consisting of sparingly water-soluble or insoluble soil organic matter were obtained from humic horizons of two soils by precipitation of organics dissolved in tetrahydrofuran by addition of water. The particles could then be size fractionated by centrifugation, and coarse fraction obtained from humic horizon formed under spruce forest was tested for effects on complex microbial community developing under laboratory conditions. The results indicate that low concentration (20mg/L) of the particles is efficient to affect the composition of the bacterial community revealed by terminal restriction fragment length polymorphism. The work contributes to understanding the factors that determine the composition of soil microbial community.

Middle age enhances expression of innate immunity genes in a female mouse model of pulmonary fibrosis.

The lungs are highly sensitive to tissue fibrosis, with a clear age-related component. Among the possible triggers of pulmonary fibrosis are repeated inhalations of fine organic particles. How age affects this response, is still far from being fully understood. We examined the impact of middle-age on gene expression in pulmonary fibrosis, using the novel "inhalation challenge set" mouse model. Our results demonstrate that the response of female mice to exposure of Pantoea agglomerans extract primarily involves various immune-related pathways and cell-cell/cell-extracellular matrix interactions. We found that middle-age had a strong effect on the response to the P. agglomerans-induced lung fibrosis, featured by a more rapid response and increased magnitude of expression changes. Genes belonging to innate immunity pathways (such as the TLR signaling and the NK-cell mediated cytotoxicity) were particularly up-regulated in middle-aged animals, suggesting that they may be potential targets for the treatment of pulmonary fibrosis caused by inhalations of organic particles. Our analysis also highlights the relevance of the "inhalation challenge set" mouse model to lung aging and related pathology.

Filter design impacton drainpipe water intake capacity

The city of Arkhangelsk is located on a marshy plain, where the groundwater level used to coincide with the surface. The area preparation for construction consisted in filling a layer of sand over peat. Hence, the following characteristic geotechnical conditions of the newly developed areas: high groundwater level and long-term settlement of peat under sand embankment. That is why subsurface structures are protected by a drainage, and drains are installed over pile foundations. One problem developing in the course of drain operation and requiring expensive re-installation activities is clogging of drain filters with fine organic and clay particles carried over by groundwater flow. The article presents the results of a survey of a building erected more than 30 years ago, which suffered from groundwater table rising due to the reduction of drain system's water intake capacity. Clogging of crushed stone cover above the drainpipe resulted in the reduction of the permeability factor. Laboratory surveys were conducted to estimate the reliability of drains with the pipes wrapped in geotextile. Drains with a layer of geotextile surrounding the stone filtering cover were also investigated. To simulate clogging, humus and clay particles were added to the water running through the filtering tube. It turned out that the second geotextile arrangement – around the stone cover with sand backfillingwas the most effective.

Potential use of rare earth oxides as tracers of organic matter in grassland

AbstractTracing organic matter (OM) in soil is challenging, because runoff and leaching processes are interrelated and have multiple sources. Therefore, multiple tracers with low background concentrations such as rare earth element oxides (REOs) are necessary to delineate the origin of sources of the organic materials in groundwater, rivers or in catchments. The main objective of this study was to examine the potential use of REOs as a tracer in various forms of OM (1) whole slurry, (2) solid, and (3) liquid phase of cattle slurry after mechanical separation. A laboratory experiment was carried out using five REOs (La, Gd, Sm, Pr, and Nd oxides) mixed directly into soil or mixed with various fractions of cattle slurry and then applied to the soil surface. In the additional grassland experiment, Gd oxide was spiked with soil and cattle slurry and then applied to the soil surface. The mineral N in the liquid phase (urine) of the slurry in the grassland experiment was labelled with 15N urea (16 atom%). In the laboratory experiment, results showed that the five REOs concentration of soil in 0–1 cm soil section after the rainfall simulation was still up to 20 times more than the background values. In 1–2 cm soil section, the concentration of only Gd (two fold higher) and La oxides (50% higher) were significantly higher than the soil background values. Therefore, we hypothesized that Gd and La oxides were associated also with relatively finer organic particles in slurry, thus 1–2 cm soil section were enriched with these oxides. The five REOs concentration below 2 cm soil depth were similar to the background values in all treatments. In line with the laboratory experiment, Gd concentrations in the deeper soil layers (2–4 and 4–8 cm) in the grassland experiment were not significantly affected by any treatment. Both in grassland and laboratory experiment, solid phase of the slurry (dung) was collected from the soil surface after rainfall simulation. Here, about 56% of REOs were measured on the solid phase of the slurry which indicates the strong binding potential of REOs on slurry OM. The present novel study, where REO tagged slurry was uniquely tested to study geochemical cycle of organic fertilizers, clearly highlighted the potential for their use as multiple‐tracers of (animal derived‐) OM in agricultural soils.

Retention and remobilization dynamics of fine particles and microorganisms in pastoral streams

Both microbial metabolism and pathogen retention and remobilization are dependent on downstream transport of fine particles, which migrate in a series of deposition and resuspension events. All fine particles, including clay minerals, particulate organic carbon, nutrients and microbes, are often considered to be transported similarly in the environment because of a lack of specific observations comparing their relative transport. We conducted a tracer injection study to compare the transport and retention of the fecal indicator bacterium Escherichia coli, synthetic inert fluorescent fine particles, and a dissolved conservative tracer. We found that the fluorescent fine particles and bacteria were transported similarly, with both having greater retention than the solute tracer. We used a stochastic model to evaluate in-stream retention and migration of the solute, fluorescent particles, and E. coli. The best-fit model parameters indicate that different stream reaches had varied retention characteristics, but always showed greater retention of fluorescent particles and E. coli compared to the solute tracer. Direct measurements within known retention areas after the injection showed that the majority of the fluorescent particles and E. coli were retained near the sediment–water interface in macrophyte stands or filtered within the top 3 cm of the streambed sediment. Both the tracer particles and E. coli were retained within these regions for multiple months following the injection experiment. The stochastic model properly captured the wide range of storage timescales and processes we observed in the stream. Our results demonstrate the importance of the streambed sediment and in-stream macrophytes as short- and long-term reservoirs for fine organic particles and microbes in streams.

Separation of fine organic particles by a low-pressure hydrocyclone (LPH)

The separation performance of a low-pressure hydrocyclone was tested using fine organic particles from 1 to 700μm. The dimensions of the low-pressure hydrocyclone were an inflow diameter of 30mm, a cylinder length of 575mm, an overflow diameter of 60mm, an underflow diameter of 50mm, a cylinder diameter of 335mm and a cone angle of 68°. The low-pressure hydrocyclone was operated with a lower inlet pressure (average 1.38–5.56kPa) that could be maintained under water level differences that ranged from 17.5 to 53.5cm between the water surface of the feeding mass cylinder and the middle of the inlet pipe of the low-pressure hydrocyclone. By varying the inflow rate, underflow ratio and feed concentration, the separation performance of the low-pressure hydrocyclone was affected. The separation performances were determined from total separation efficiency and grade efficiency. Separation performances were determined according to the different inflow rates of 400, 600, 800 and 1000mls−1 and their respective underflow ratios that ranged from 5% to 30%. The maximum total separation efficiencies for each inflow rate were 41%, 46% and 46% at 400, 800 and 1000mls−1 inflow rates, respectively, and at underflow rates of 30% of the inflow rates. In addition, a total separation efficiency of 46% was employed at 600mls−1 of inflow rate and with an underflow rate of 25% its inflow rate. As the feed concentration increased from 25 to 150mgl−1, the separation performances were gradually decreased. For the fine particles ranging 1–200μm, the grade efficiency was higher at the higher inflow rate (higher than 600mls−1) and higher underflow rate. However, for the coarse particles ranging 400–700μm, the grade efficiency was higher at the lower inflow rate (lower than 600mls−1) and higher underflow rate. The cut-point (d50) values ranged from 30 to 200μm for a feed size range of 1–700μm. The Response Surface Method (RSM) model predicted an optimum operating inflow rate and underflow ratio of 721mls−1 of inflow rate and 30%, respectively, for the low-pressure hydrocyclone at a maximum total separation efficiency. Based on these findings, further design and operating adaptation of low-pressure hydrocyclones used for fine solids removal in recirculating aquaculture systems is expected.

Reduced root anchorage of freshwater plants in sandy sediments enriched with fine organic matter

Summary The decline of submerged macrophytes in nutrient‐enriched lakes has been explained by shading from phytoplankton. Reduced anchorage in softer organic sediments may, however, enhance the loss of submerged macrophytes; therefore, we tested whether increased water content results in a decline of anchorage of artificial root systems and isoetid species in sandy sediments enriched with fine organic particles, and compared anchorage and hydraulic drag for short isoetid and tall elodeid species to evaluate the risk of uprooting. Constructed and natural sandy sediments followed the same hyperbolic relationship of higher water content with increasing organic content. Anchorage of artificial root systems peaked in sediments containing small amounts of organic matter (0.7–1.2% dry weight) and water (20–27% WW) and was up to six times higher compared with more organic‐rich sediments. Anchorage of the isoetid, Lobelia dortmanna, in natural sandy sediments increased linearly with plant weight and root surface area and declined with higher organic content of sediments. Multiple regression models could account for the positive influence of plant size on root anchorage and the negative influence of organic matter and water in sediments. Hydraulic drag on rigid shoots of three isoetid species increased with the second power of water velocity. The species‐specific drag coefficient was consistently high for these isoetids and markedly lower and declining with increasing velocity for two elodeids with flexible tissue. Anchorage of two isoetid species in mineral and more organic sediments from shallow water markedly exceeded estimated hydraulic drag under storm events inducing 0.6 m s−1 currents, while elodeid species were only safely rooted in firm mineral sediments. These findings are in agreement with the growth of isoetids in wave‐exposed shallow waters, while elodeids prefer deeper or sheltered sites. The multiple regression models predicted that L. dortmanna could attain critically low anchorage on highly organic sediments in accordance with observations of plant‐free littoral sediments of colloidal organic texture. Because it is well established that sediment anoxia severely impairs root development of L. dortmanna, enrichment of sediments with labile organic matter may represent a double jeopardy by reducing root development and anchorage.

Macrobenthic communities of the Vellar Estuary in the Bay of Bengal in Tamil-Nadu in South India

The macrobenthic fauna and communities of the Vellar Estuary located at the southeast cost of India (11°30′ N, 79°45′ E) and the adjacent marine and river habitats are described on the basis of original data (70 samples over 10 transects). The fauna consists of 115 macrobenthic species and 79 species in estuarine habitats. We described 14 types of macrobenthic communities with different compositions of the dominant species. The leading ecological factors of the distribution of the communities are the salinity, depth, and bottom type. The Vellar estuary consists of two longitudinal zones of macrobenthos. The polyhalinic area is populated by the marine species, but it is related not to a salinity decrease but to the protection from waves and silt on the bottom in this area. The polyhalinic communities are most abundant in terms of the biomass and species richness. The mesohalinic area is inhabited by brackish water species and communities with low abundance. The sublittoral estuarine area is dominated by filter-feeders—the bivalves Crassostrea madrasensis, Meretrix casta, Modiolus metcalfei, and Scapharca inaequivalves—and the littoral zone is dominated by the gastropods Cerithidea cingulata, some crabs, and polychaetes. The ecosystem function of the Vellar estuary can be defined as a filter for the fine organic particles transported by the river.

The Groups and Distribution Characteristics of Fine Organic Autotrophic Particles in a Subtropical Reservoir Using Flow Cytometry

Flow cytometry was applied in the study of the groups and spatial distribution characteristics of the fine particles in Bantou—Shidou Reservoir, a subtropical reservoir in Xiamen,China. The fine organic autotrophic particles in reservoir could be divided into four groups conspicuously: R2 group in the smallest size with much phycoerythrin but little chlorophyll; R1 and R4 groups in relatively large size: R1 group with certain phycoerythrin and chlorophyll, while R4 group with no phycoerythrin but much chlorophyll; R3 group in the largest size with certain phycoerythrin and a large amount of chlorophyll. All the sampling stations in Shidou ( upper reaches) and Bantou ( lower reaches) reservoirs contain maximum R1 group with quantity between 35.41-46.85×106 ind/L and 23.39-43.02×106 ind/L; and minimum R3 group with quantity between 0.20-0.58×106 ind/L and 0.22-0.78×106 ind/L. The quantity of fine organic autotrophic particles is larger than that of organic azoic particles and inorganic particles. In view of the spatial distribution, R1 and R3 groups distribute unevenly in Shidou reservoir, while R2 and R4 groups change a little in quantity in different sampling stations and distribute much evenly. Moreover, in Bantou reservoir, R1, R2 and R3 groups distribute unevenly in the sampling stations, while R4 group distributes relatively evenly. The fast and multi-parameter detection capacity of Flow cytometry provides a much effective mean for the research on water fine organic autotrophic particles.

Intriguing Phenomena at the Boundary between Metal Oxide - Organic Fine Particles and their Industrial Application

When metal oxide fine particles are subjected to mechanical stressing with organic powders such as fluoropolymers or amino acids, oxidative decomposition of organics is catalyzed by the coexisting metallic species, and partial anion exchange in the oxides takes place simultaneously. The phenomena serve as new technology of producing various functional particles with many applications, by utilizing their absorption ability of various photon energies and rational preparation of core-shell particles. Case studies, including nanoparticles of Nb2O5 for smart synthesis of complex oxides for electroceramics, and TiO2 for antibacterial photocatalysis are given, after surveying general needs for fine particle surface modification for the purpose of functionalization.

Palaeoenvironmental reconstruction of Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland

ABSTRACT Gedl, P., Kaim, A., Leonowicz, P., Boczarowski, A., Dudek, T., Kędzierski, M., Rees, J., Smoleń, J., Szczepanik, P., Sztajner, P., Witkowska, M. and Ziaja, J. 2012. Palaeoenvironmental reconstruction of Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Krakow-Silesia Homocline, Poland. Acta Geologica Polonica, 62(3), 463-484. Warszawa. Multidisciplinary studies of the Middle-Upper Bathonian ore-bearing clays at Gnaszyn revealed variable palaeoenvironmental conditions during the deposition of this seemingly monotonous sequence. We interpret the conditions in the bottom environment and the photic zone, and also evaluate the influence of the adjacent land areas, based on sedimentology, geochemistry, sporomorphs and palynofacies composition, benthic (foraminifera, gastropods, bivalves, scaphopods, echinoderms), planktonic (calcareous nannoplankton, dinoflagellate cysts), and nektonic (sharks) fossils. The Gnaszyn succession originated relatively close to the shore, within reach of an intense supply of terrestrial fine clastic and organic particles. The latter are mainly of terrestrial origin and range from 1.5 to 2.5 wt.%. The precise water depth is difficult to estimate but most likely ranges from several tens of metres to a few hundred metres. All fossil groups show minor changes throughout the succession. As the climate seems to have been quite stable during this period we consider sea-level fluctuations to have been the main factor responsible for the changes. The terrestrial input, including freshwater and land-derived clastic and organic particles (sporomorphs and cuticles), increased during periods of sea-level lowstand. As a consequence, stress conditions (lower salinity, higher nutrient availability, lower water transparency) in the photic zone caused blooms of opportunistic planktonic taxa. Furthermore, a faster sedimentation rate led to oxygen depletion and deterioration of the living conditions in the bottom environment due to an increased accumulation of organic matter. As a result, the benthic biota became taxonomically impoverished and commonly dominated by juvenile forms. During periods of high sea level, the source areas were shifted away from the basin, resulting in a decrease in the terrestrial influx, increase in the salinity of surface waters, the appearance of more diverse phytoplankton assemblages, a lower sedimentation rate, and an improvement of living conditions at the bottom.

The β-richness of two detritivore caddisflies affects fine organic matter export

We used stream networks as a model system to test whether the ecosystem function, upstream production, and export of fine organic particles, an important subsidy to downstream habitats, would vary between two stream networks with identical detritivore species but different spatial distributions (i.e. high or low β-richness). Our experiment employed artificial stream networks with two simulated tributaries. We used two species of detritivorous caddisflies, Lepidostoma sp. and Pycnopsyche guttifer, in either sympatry (low β-richness) or allopatry (high β-richness) in the tributaries of each network. The tributaries were given either senesced or green speckled alder (Alnus incana rugosa). In the networks with senesced leaves, particle export was more than twice as great when the detritivores were in allopatry whereas interference competition in sympatry reduced particle export. In the networks with green leaves, particle export did not significantly vary between the allopatric and sympatric distributions because the interference competition was reduced and the two species had similar feeding rates on green leaves. Humans are altering β-richness by homogenizing or differentiating flora and fauna across habitats; however, little is known about how altering this type of biodiversity will affect ecosystem functions. Our experimental manipulation is a simple version of a change in the β-richness of the detritivores in a more complex stream network in nature. These results may indicate that shifts in species distributions across sites may significantly affect ecosystem functions, even when no species are lost from a watershed.

Production of Fine Organic Crystalline Particles by Using Milli Segmented Flow Crystallizer

In the pharmaceutical production field, it is required to produce organic fine crystalline particles having a monodispersed crystal size distribution (CSD). Anti-solvent crystallization is one method for producing crystal particles. In order to produce fine crystalline particles and/or crystals having a monodispersed CSD, several methods such as segmented flow in the tubular crystallizer, ultrasound irradiation, and modulated operation in batch cooling crystallization have been studied in previous studies. In this study, integrated operation of ultrasound irradiation and temperature modulation at a milli-sized segmented flow has been carried out to produce organic fine crystalline particles having a monodispersed CSD in the anti-solvent crystallization. Taurine (solute)–water (solvent)–EtOH (anti-solvent) system is employed. The effect of segmented flow on mixing solution has been observed with a high-speed microscope. Fine crystalline particles which have tens of microns average size are obtained with the integration of ultrasound irradiation and temperature modulation on a milli-sized segmented flow. Furthermore, crystals of 10 µm size are produced under controlled supersaturation condition. Additionally, it is suggested that the CSD could be improved by introducing temperature modulation after nucleation.

Contributions from DMS and ship emissions to CCN observed over the summertime North Pacific

Abstract. Measurements of cloud condensation nuclei (CCN) made over the North Pacific Ocean in July 2002 are analysed with concurrent measurements of aerosol number, mass and composition. Overall the CCN are controlled by the sulphate, including one case that suggests particle nucleation and growth resulting from dimethyl sulphide oxidation that enhanced CCN concentrations. Hourly CCN concentrations are correlated with concentrations of sulphate plus methanesulphonic acid (MSA) over the entire study period (r2=0.43 and 0.52 for supersaturations of 0.34% and 0.19%, respectively), and are not well correlated with other organics (r2&lt;0.2). One case study reveals elevated mass and number concentrations of ultrafine and fine organic particles due to regional ship emissions, identified through quadrupole aerosol mass spectrometer (Q-AMS) measurements, during which organic mass concentrations are correlated with CCN values (r2=0.39 and 0.46 for supersaturations of 0.19% and 0.34%, respectively). The evolution of the time series and mass distributions of organics, sulphate and MSA over this timeframe indicate that the regional distribution of small, diffuse ship-sourced organic particles act as condensation sites for sulphur species, resulting in a subsequent increase in number concentrations of CCN. We conclude that, where present, direct emissions of anthropogenic organic particles may exert a strong control on marine CCN concentrations once diffused into the marine atmosphere, by acting as condensation sites for biogenic and anthropogenic sulphur species.

An Experimental Study on Organic Fine Particles Movement in a Sand Column

The aim of this study is to investigate a movement mechanism of organic fine particles (OFP) in a sand column, which is a useful knowledge in a restoration of aggravated tidal flat and a construction of man-mad sandy tidal flat. It was found that Hagen-Poiseuille equation could express the characteristics of flow in the sand column; and the pressure loss inside the sand column considering OFP could be formulated theoretically. The movement of OFP in the sand column estimated from the formula was verified by experiments. Moreover, the organic properties of OFP strongly affected the movement; namely, decomposed OFP were easy to travel through the sand column.