WorldWideScience
 
 
1

Harmful Algae, Nuisance Blooms and Anthropogenic Nutrient Enrichment  

Environmental Research Database

DescriptionPhytoplankton is the collective name given to the microscopic floating plants in seas and lakes. Under certain conditions, the abundance of phytoplankton as a whole or of one or more species in particular, can reach a magnitude at which it is visible through discolouration of the sea. Some of these blooms because of the colour of the water have been called 'Red Tides'. Blooms of some 300 species of the phytoplankton are known as Harmful Algal Bloom (HAB) species in recognition of their poten [continued...

2009-01-31

2

Genomic blueprint of Hahella chejuensis, a marine microbe producing an algicidal agent  

UK PubMed Central (United Kingdom)

Harmful algal blooms, caused by rapid growth and accumulation of certain microalgae in the ocean, pose considerable impacts on marine environments, aquatic industries and even public health. Here, we...Full Text Available

2005-01-01

3

Nutrient Pollution of Coastal Rivers, Bays, and Seas  

Science.gov (United States)

This 'Issues in Ecology' article from the Ecological Society of America provides information about the consequences of nutrient enrichment along the US coast. It describes problems such as harmful algal blooms (HABs), anoxia, hypoxia, and dead zones. It explains which nutrients are involved and describes implications of excess nutrients in regions such as the Gulf of Mexico/Mississippi River basin. The article features several color photographs, maps, and diagrams.

4

Nitrogen Nutrition of Harmful Algal Blooms in the Benguela Upwelling System  

Environmental Research Database

DescriptionBoth wild and aquaculture reared abalone, mussels and other shellfish of commercial importance as a food resource to man can be afflicted by poisoning if they feed on toxic species of small single-celled planktonic marine algae. If humans consume these shellfish that have become intoxicated by HAB's, illness or even death may occur. HAB's occur world-wide, but some regions are more severely affected than others. The incidence of HAB's also appear to be on the increase globally, perhaps because o [continued...

2008-01-30

5

Anomalous carbon isotope fractionation between atmospheric CO/sub 2/ and dissolved inorganic carbon induced by intense photosynthesis  

Energy Technology Data Exchange (ETDEWEB)

A stable isotope mass-balance of dissolved inorganic carbon during a blue-green algae bloom in a softwater lake demonstrates that at low partial pressure of carbon dioxide there must be a large net negative carbon isotope fractionation between atmospheric CO/sub 2/ and the CO/sub 2/ absorbed by lake water at pH = 9.5. Chemical enhancement of CO/sub 2/ invasion at high pH by the reaction CO/sub 2/ + OH/sup -/ ..-->.. HCO/sub 3//sup -/ at large apparent film thicknesses may result in carbon isotope fractionation approaching that for a hydroxide solution. This phenomenon, coupled with a decrease in the photosynthetic fractionation, forced the surface water of a softwater lake to achieve increasingly negative delta /sup 13/C values during an algal bloom, which is in the opposite sense to the trend that results from photosynthesis under less extreme conditions. This and other similar systems must operate under non-equilibrium ...

1987-04-01

6

Phytoplankton bloom in commercial shrimp ponds using green-water technology  

British Library Electronic Table of Contents (United Kingdom)

Phytoplankton community composition, density, and succession were studied in tropical commercial ponds with euryhaline tiger shrimp (Penaeus monodon Fabricius) using green-water technology at two different stocking densities [T1 10 post-larvae (PL) m?2 and T2 15 PL m?2] in one grow-out season (May?October 2005) in Leganes, Iloilo, Philippines. Weekly qualitative and quantitative analyses of phytoplankton were done along with physicochemical analyses of the pond waters. A total of 103 taxa belonging to nine different algal classes were observed. Of these classes, the Chlorophyceae, Cyanophyceae and Bacillariophyceae constituted the great bulk of the phytoplankton population. The two treatments did not show any significant differences in the growth pattern of phytoplankton over time and in t...

2007-01-01

7

Study of coastal water zone ecosystem health in Zhejiang Province based on remote sensing data and GIS  

British Library Electronic Table of Contents (United Kingdom)

The coastal ecosystem health assessment is a field of increasing importance. In this paper, a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made, mainly based on remote sensing data and GIS technique. Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development. Firstly, human activities, hydrology and ecosystem problems in the study area were discussed and analyzed. Secondly, from 4 aspects of human stress, physical, chemical and biological responses to anthropogenic activities and natural stress, several indicators such as water transparency (Secchi Disk Depth, SDD), suspended substance concentration, dissolved inorganic nitrogen, active phosphate, chlorophyll, harmful algae bloom, as well as distr...

2010-01-01

8

Analytical surveys on water quality of Trasimeno Lake: Definition of trophic levels; Indagine sulla qualita` delle acque del Lago Trasimeno: Definizione dei livelli trofici  

Energy Technology Data Exchange (ETDEWEB)

The previous judgment of eutrophic state, once proposed for the Trasimeno Lake (Umbria region, Italy), has been revised. According to Vollenweider-OECD classification criterion, the lake waters are at present to be classified as mesotrophic waters, with phosphorus limitation. However this level of moderate productivity results to be conditioned by the hydrochemical characteristics of the lake waters, that control phosphorus concentrations independently from the loading coming from the basin, and prevent dangerous and massive algal blooms. Different processes of chemical nature, regulating the phosphorus amount in the lake waters, are then reviewed: adsorption of P/P0(4) onto suspended materials, particularly clay mineral particles, and direct precipitation as hydroxylapatite or co-precipitation with carbonates, are found to be the principal mechanisms that determine chemical removal of phosphorus from the water column. A preliminary mass ...

1995-06-01

10

Integrated vermi-pisciculture - an alternative option for recycling of solid municipal waste in rural India  

Energy Technology Data Exchange (ETDEWEB)

Vermicomposts as a biofertilizer can be a great option for pond manuring as they never cause any long term harm to the soil like chemical fertilizer. In this study vegetable and horticulture waste was used as an important media for vermiculture. Three separate cemented tanks (6 m{sup 3} each) were used in the system as control tank, vermicompost fertilized tank and inorganic fertilizer manured tank. Monoculture of fish was carried out with cat fish, Clarias batrachus. The produced earthworms were used as fish feed. Regular monitoring of water parameter was conducted in three different ponds. Specifically, the algal biomass variation was quite helpful in analysing the behavior of the ponds. NPK value of soil samples was analyzed intermittently to know the eutrophication level. Despite the hot summer temperature in northern part of India, which is not ideal for fish growth, we have recorded an encouraging growth performance in organic manured ...

2004-05-01

11

Concurrent Exposure of Bottlenose Dolphins (Tursiops truncatus) to Multiple Algal Toxins in Sarasota Bay, Florida, USA  

UK PubMed Central (United Kingdom)

Sentinel species such as bottlenose dolphins (Tursiops truncatus) can be impacted by large-scale mortality events due to exposure to marine algal toxins. In the Sarasota Bay region...Full Text Available

12

Bioavailability of organic matter in a highly disturbed estuary: The role of detrital and algal resources  

UK PubMed Central (United Kingdom)

The importance of algal and detrital food supplies to the planktonic food web of a highly disturbed, estuarine ecosystem was evaluated in response to declining zooplankton and fish populations. We assessed...Full Text Available

2002-06-11

13

abstract - 2008 NASA Carbon Cycle and Ecosystems Joint Science ...  

Science.gov (United States)

Microscopy and chemotaxonomy from HPLC analysis of phytoplankton pigments initiated in 2003 suggest that Noctiluca miliaris blooms are becoming more intense ...

14

Nitrogen utilization during spring phytoplankton bloom development in the southeast Bering Sea  

Energy Technology Data Exchange (ETDEWEB)

Interactions beween a high latitude, continental shelf, spring phytoplankton bloom and water column physics and chemistry were studied using /sup 15/N measured rates of nitrogen uptake. Peak bloom conditions commenced when the mixed layer shallowed and minimized respirational losses. Integrative light-mixing growth models were accurate during early bloom stages. An advection-diffusion model associated peak bloom nitrate uptake with pycnocline mixing rates of 2.1 m d/sup -1/ in an 18 m mixed layer. Maximum nitrogen specific uptake rates (hr/sup -1/), unlike those of carbon, coincided with peak bloom conditions. Although species compositions among peak bloom periods were similar, particulate C/N ratios were not. Apparently, both intercellular factors and prevailing mixing conditions influence specific uptake rates and cell composition. A large proportion of new ...

1983-01-01

15

Mathematical model of heat transfer for bloom continuous casting  

British Library Electronic Table of Contents (United Kingdom)

A mathematical model for heat transfer during solidification in continuous casting of automobile steel, was established on researching under the influence of the solidifying process of bloom quality of CCM in the EAF steelmaking shop, at Shijiazhuang Iron and Steel Co. Ltd. Several steel grades were chosen to research, such as, 40Cr and 42CrMo. According to the results of the high temperature mechanical property tests of blooms, the respective temperature curves for controlling the solidification of different steels were acquired, and a simulating software was developed. The model was verified using two methods, which were bloom pinshooting and surface strand temperature measuring experiments. The model provided references for research on the solidifying process and optimization of a secon...

2008-01-01

16

Quark-Hadron Duality: Resonances and the Onset of Scaling  

Energy Technology Data Exchange (ETDEWEB)

We discuss the origin of Bloom-Gilman duality and the relationship between resonances and scaling in deep-inelastic scattering. We present a simple quantum mechanical model which reproduces the essential features of Bloom-Gilman duality at low Q{sup 2}, and describe applications of local duality relating structure functions at x{approximately}1 and elastic electromagnetic form factors.

2001-03-01

17

The harmful effect of phosphate in yellow cake on the TBP purification process  

International Nuclear Information System (INIS)

The harmful effect of phosphate in yellow cake on the TBP purification process and its removal methods are dealed with. The reason of more uranium loss in residue was analyzed. The harmful effect of phosphate on TBP extraction efficiency and operaton of extraction column was discussed. The limit value of uranium concentration in digestion solution was presented. For TBP purification process, the presence of phosphate in yellow cake does more harm than good. (authors)

2009-02-01

19

Allelopathic interactions between Prorocentrum micans and Skeletonema costatum or Karenia mikimotoi in laboratory cultures  

British Library Electronic Table of Contents (United Kingdom)

Algal allelopathy is an ecological/physiological phenomenon that has focused attention on the interactions among algae and the production of algal toxins. We investigated the allelopathic interactions between the dinoflagellate genus Prorocentrum micans and diatom genus Skeletonema costatum and between P. micans and dinoflagellate genus Karenia mikimotoi using bi-algal cultures. Because the effects were species-specific and size-dependent, we evaluated the effect of different initial densities. At low densities of P. micans and high densities of S. costatum inoculated into the same medium, the growth of P. micans was weakly restrained, whereas the growth of S. costatum was significantly suppressed. S. costatum and K. mikimotoi were strongly inhibited by P. micans, in both the bi-algal cult...

2011-01-01

20

Phenology of phytoplankton blooms in the Nova Scotian Shelf-Gulf of Maine region: remote sensing and modeling analysis  

British Library Electronic Table of Contents (United Kingdom)

Remotely sensed ocean color data and numerical modeling have been used to study the phenology of both spring and fall phytoplankton blooms (FPBs) in the Nova Scotian Shelf (NSS)-Gulf of Maine (GoM) region. The ocean color data reveal a general pattern of westward progression of the spring phytoplankton bloom (SPB), and an eastward progression of the FPB in the NSS-GoM region. The spatial pattern of mean chlorophyll concentration in spring is similar to that in fall, with a lower concentration in the NSS and higher in the GoM. Interannually, there is a weak but significant tendency for years with earlier (delayed) SPBs to be followed by delayed (earlier) FPBs, but the mean chlorophyll concentrations during SPBs are not correlated with those during FPBs. The interannual variability of SPB ti...

2010-01-01

 
 
 
 
21

Microcystins Induce Morphological and Physiological Changes in Selected Representative Phytoplanktons  

British Library Electronic Table of Contents (United Kingdom)

Dissolved microcystins (MCs) are regularly present in water dominated by microcystin-producing, bloom-forming cyanobacteria. In vitro experiments with environmentally feasible concentrations (5 ? 10?7 M) of the three most common microcystins, MC-LR, MC-RR, and MC-YR, revealed that they influence the metabolism of different representative phytoplanktons. At light intensities that are close to the cyanobacterial bloom environment (50??mol m?2 s?1), they produce morphological and physiological changes in both microcystin-producing and -nonproducing Microcystis aeruginosa strains and also have similar effects on the green alga Scenedesmus quadricauda that is frequently present in cyanobacterial blooms. All three microcystin variants tested induce cell aggregation, increase in cell volume, and ...

2006-01-01

22

Comparison of toxicity to terrestrial plants with algal growth inhibition by herbicides  

Energy Technology Data Exchange (ETDEWEB)

The toxicities of 21 different herbicides to algae (Selenastrum capricornutum and Chlorella vulgaris) and to terrestrial plants (radishes, barley, and bush beans or soybeans) were compared to order to determine the feasibility of using a short-term (96-h) algal growth inhibition test for identifying chemicals having potential toxicity in a 4-week terrestrial plant bioassay. The toxicity of each test chemical, usually in combination with a commercial formulation, was evaluated at six nominal concentrations, between 0 and 100 mg/L growth medium in the algal bioassay or between 0 and 100 mg/kg substate in the terrestrial plant bioassay, in terms of both (1) the no-observed-effect concentration (NOEC), i.e., the highest concentration tested at which no significant (P < 0.05, one-sided test) reduction in algal growth rate or in terrestrial plant yield, relative to controls, was observed; and (2) the concentration at which ...

1984-10-01

23

Plant and algal interference in bacterial beta-D-galactosidase and beta-D-glucuronidase assays.  

UK PubMed Central (United Kingdom)

Several commonly occurring freshwater and marine plants and algae were screened for beta-D-galactosidase and beta-D-glucuronidase activities by using a 60-min enzyme assay based on the hydrolysis by...Full Text Available

1994-11-01

24

Light-induced Adhesion of Spirogyra Cells to Glass 1  

UK PubMed Central (United Kingdom)

Adhesion of Spirogyra (tentatively, Spirogyra fluviatilis) cells to glass is described. The cells of an algal filament can adhere to a substrate only when they are...Full Text Available

1977-04-01

25

Complete plastid genome sequences suggest strong selection for retention of photosynthetic genes in the parasitic plant genus Cuscuta  

UK PubMed Central (United Kingdom)

BackgroundPlastid genome content and protein sequence are highly conserved across land plants and their closest algal relatives. Parasitic plants, which obtain some or all of their...Full Text Available

26

The utilization of polysaccharides by heterotrophic bacterioplankton in the Bay of Biscay (North Atlantic Ocean)  

British Library Electronic Table of Contents (United Kingdom)

This study investigates the turnover of polysaccharides by heterotrophic bacterioplankton in the northern Bay of Biscay, a productive marine system on the continental margin of the temperate Atlantic Ocean. Bacterial biomass production (BBP) near the surface ranged from 0.5 to 25.7 nmol C L?1 h?1 during small phytoplankton blooms in May and June that occurred after the main spring bloom. A direct relationship between BBP and total polysaccharides strongly suggests the dependence of bacterial growth on the availability of semi-labile organic matter. Concentrations of combined glucose as well as rate constants of extracellular glucosidase activity and glucose uptake were determined to estimate the actual carbon fluxes from bacterial polysaccharide turnover. Results reveal that ...

2011-01-01

27

Different tolerances and responses to low temperature and darkness between waterbloom forming cyanobacterium Microcystis and a green alga Scenedesmus  

British Library Electronic Table of Contents (United Kingdom)

The dynamics of planktonic cyanobacteria in eutrophicated freshwaters play an important role in formation of annual summer blooms, yet overwintering mechanisms of these water bloom forming cyanobacteria remain unknown. The responses to darkness and low temperature of three strains (unicellular Microcystis aeruginosa FACHB-905, colonial M.?aeruginosa FACHB-938, and a green alga Scenedesmus quadricauda FACHB-45) were investigated in the present study. After a 30-day incubation under darkness and low temperature, cell morphology, cell numbers, chlorophyll a, photosynthetic activity (ETRmax and I k), and malodialdehyde (MDA) content exhibited significant changes in Scenedesmus. In contrast, Microcystis aeruginosa cells did not change markedly in morphology, chlorophyll a, photosynthetic activi...

2008-01-01

28

Elucidating novel pathways and regulation of nitrogen assimilation in alpha proteobacteria exemplified by the soil organism Paracoccus denitrificans  

Environmental Research Database

DescriptionThe importance of inorganic nitrate for the nutrition and growth of marine and freshwater autotrophic phytoplankton has long been recognised, in particularly because of the 'blooms' formed in nitrate and phosphate polluted water and their possible roles as carbon dioxide sinks. By contrast, the utilisation of nitrate by heterotrophic bacteria has historically received less attention. Up until now, the primary role of heterotrophic bacteria has classically been considered to be the decomposition [continued...

2010-01-31

29

Primary productivity C-14 and algal assay in the study of water pollution effects in the Citarum River and Jatiluhur Reservoir  

International Nuclear Information System (INIS)

Water quality of the Citarum River and the Jatiluhur Reservoir in Indonesia was evaluated using C-14 radioisotope. A close relationship between the abiotic (physical and chemical) and the biotic (algal growth potential, primary productivity, chlorophylla and diversity index of planktonic and benthic macroinvertebrate) parameters was obtained. Algal growth potential to abiotic parameters relationship has the highest correlation coefficient and can be used as a pollution indicator. The other biotic parameters do not show clear relationship with the abiotic parameters. The Citarum water quality is the lowest in those locations which receive human and industrial waste from Bandung and its environment. This water cannot be used for drinking purposes and fishery. The water quality in other locations of the river, however, meets the criteria for agriculture. Agricultural waste does not show any drastic effect on the water quality profile due to ...

1983-03-01

30

Existing systems review of treatment media for the Bear Creek Valley treatability study, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee  

Energy Technology Data Exchange (ETDEWEB)

In situ treatment has been proposed as a remediation alternative for surface water and groundwater contaminated with uranium and nitrate as a result of former waste disposal practices in the S-3 Ponds. Interceptor trenches containing reactive media have been proposed to treat groundwater, and constructed wetlands and/or algal mats are potential alternatives for treating surface water. This report presents the results from testing of ten different reactive media, and combinations of media, that are candidates for use in the proposed interceptor trenches to remove uranium and nitrate from groundwater. It also presents the results of testing and evaluation of algal mats and wetlands for removing uranium and nitrate from surface water.

1998-01-01

31

Nucleotide sequence of a Euglena gracilis chloroplast gene coding for the 16S rRNA: homologies to E. coli and Zea mays chloroplast 16S rRNA.  

UK PubMed Central (United Kingdom)

The nucleotide sequence of 16S rDNA from Euglena gracilis chloroplasts has been determined representing the first complete sequence of an algal chloroplast rRNA gene. The structural part of the 16S...Full Text Available

1982-10-25

32

Copper removal by algal biomass: Biosorbents characterization and equilibrium modelling  

Energy Technology Data Exchange (ETDEWEB)

The general principles of Cu(II) binding to algal waste from agar extraction, composite material and algae Gelidium, and different modelling approaches, are discussed. FTIR analyses provided a detailed description of the possible binding groups present in the biosorbents, as carboxylic groups (D-glucuronic and pyruvic acids), hydroxyl groups (cellulose, agar and floridean starch) and sulfonate groups (sulphated galactans). Potentiometric acid-base titrations showed a heterogeneous distribution of two major binding groups, carboxyl and hydroxyl, following the quasi-Gaussian affinity constant distribution suggested by Sips, which permitted to estimate the maximum amount of acid functional groups (0.36, 0.25 and 0.1 mmol g{sup -1}) and proton binding parameters (pK{sup '}{sub H}=5.0,5.3and4.4;m{sub H} = 0.43, 0.37, 0.33), respectively for algae Gelidium, algal waste and composite material. A non-ideal, semi-empirical, thermodynamically ...

2009-04-30

33

The Proton structure function F(2) in the resonance region  

Energy Technology Data Exchange (ETDEWEB)

Unique measurement of the proton structure function F2 in a wide two-dimensional region of x and Q**2 has been reported. The accessible kinematics covers entire resonance region up to W=2.5 GeV in the Q**2 interval from 0.1 to 4.5 GeV**2. Obtained data allowed for the first time an evaluation of moments of the structure function F2 directly from experimental data as well as an intensive study of the Bloom-Gilman duality phenomenon.

2003-06-01

34

Diurnal variation of phytoplankton community in a high frequency area of HABs: Daya Bay, China  

British Library Electronic Table of Contents (United Kingdom)

Phytoplankton community was investigated in the cage culture area of Daya Bay during a diurnal cycle. Two rainfalls occurred during the course of the experiment and decreased the surface seawater salinity in the aquaculture area. A total of 38 species were identified, of which the dominant species included Pseudo-nitzschia spp. and Skeletonema costatum. Water stratification obstructed the vertical migration of dinoflagellates. Statistical analysis indicated that Synechococcus showed negative relationship with silicate and ammonia, which indicated that Synechococcus adapted to grow at oligotrophic environment. Phytoplankton community structure implied the risk of Pseudo-nitzschia spp. blooms in the aquaculture area of Daya Bay.

2011-01-01

35

Tobacco Chewing and Associated Factors Among Youth of Western Nepal: A Cross-sectional Study  

UK PubMed Central (United Kingdom)

Background:Smokeless tobacco is found to be as addictive and harmful as smoking but have not been explored into, especially among youth.Objectives:This...Full Text Available

2011-04-01

36

The concept of mental disorder: diagnostic implications of the harmful dysfunction analysis  

UK PubMed Central (United Kingdom)

What do we mean when we say that a mental condition is a medical disorder rather than a normal form of human suffering or a problem in living? The status of psychiatry as a medical discipline depends...Full Text Available

2007-10-01

37

Smoking cessation and lung cancer risk in an Asian population: Findings from the Singapore Chinese Health Study  

UK PubMed Central (United Kingdom)

Background:Smoking cessation is an important strategy for reducing the harmful effects of tobacco, particularly in the prevention of lung cancer; however, prospective data on the...Full Text Available

2010-09-28

38

Organizing, Educating, and Advocating for Health and Human Rights in Vieques, Puerto Rico  

UK PubMed Central (United Kingdom)

I briefly review the process of community organization, education, and advocacy activities that ended the harmful military practices in the island-municipality of Vieques, Puerto Rico, while drawing...Full Text Available

2005-01-01

39

Foreign Subtitles Help but Native-Language Subtitles Harm Foreign Speech Perception  

UK PubMed Central (United Kingdom)

Understanding foreign speech is difficult, in part because of unusual mappings between sounds and words. It is known that listeners in their native language can use lexical knowledge (about how words...Full Text Available

40

Antioxidant Defenses Predict Long-Term Survival in a Passerine Bird  

UK PubMed Central (United Kingdom)

BackgroundNormal and pathological processes entail the production of oxidative substances that can damage biological molecules and harm physiological functions. Organisms have evolved...Full Text Available

 
 
 
 
41

A tool to balance benefit and harm when deciding about adjuvant therapy  

UK PubMed Central (United Kingdom)

Adjuvant therapy aims to prevent outgrowth of residual disease but can induce serious side effects. Weighing conflicting treatment effects and communicating this information with patients is not elementary....Full Text Available

2009-03-24

42

Problems involved in developing an index of harm  

International Nuclear Information System (INIS)

Death as a criterion (age distribution of occupational death; mean loss of life years due to radiation deaths); accidents at work (incidence of accidents of certain degrees of severity); total loss of working days due to accidents; occupational diseases; somatic and genetic radiation effects; radiation effects during pregnancy (incidence of pregnancies, ristes before implantation, hazards to the embryo, hazards to the foetus, total additional risk due to radiation exposure during pregnancy); age and sex dependence of risk figures; attempted formulation of an index of harm. (HP/orig.).

1979-01-01

43

[Fe]-hydrogenases in green algae: photo-fermentation and hydrogen evolution under sulfur deprivation  

Energy Technology Data Exchange (ETDEWEB)

Recent studies indicate that [Fe]-hydrogenases and H{sub 2} metabolism are widely distributed among green algae. The enzymes are simple structured and catalyze H{sub 2} evolution with similar rates than the more complex [Fe]-hydrogenases from bacteria. Different green algal species developed diverse strategies to survive under sulfur deprivation. Chlamydomonas reinhardtii evolves large quantities of hydrogen gas in the absence of sulfur. In a sealed culture of C. reinhardtii, the photosynthetic O{sub 2} evolution rate drops below the rate of respiratory O{sub 2} consumption due to a reversible inhibition of photosystem II, thus leading to an intracellular anaerobiosis. The algal cells survive under these anaerobic conditions by switching their metabolism to a kind of photo-fermentation. Although possessing a functional [Fe]-hydrogenase gene, the cells of Scenedesmus obliquus produce no significant amounts of H{sub 2} under S-depleted ...

2002-12-01

44

Assimilation of cadmium, chromium, and zinc by the green mussel Perna viridis and the clam Ruditapes philippinarum  

Energy Technology Data Exchange (ETDEWEB)

The green mussel Perna viridis and the clam Ruditapes philippinarum have been frequently used as biomonitors of coastal contamination in subtropical and tropical waters, yet the physiological processes controlling metal uptake in these bivalves are unknown. Assimilation efficiency (AE) is an important physiological parameter quantifying metal bioavailability from ingested food. The authors determined the AEs of Cd, CR, and Zn in these bivalves feeding on five species of phytoplankton and one natural section. The influences of the cytoplasmic distribution of metals in the algal cells and the digestive physiology of bivalves on metal AEs were also examined. Among the three metals, Zn was generally assimilated at the highest efficiency, i.e., 21 to 36% in the mussels and 29 to 59% in the clams. Cr was the least assimilated metal, with AEs being 10 to 16% in the mussels and 11 to 24% in the clams. The AEs of Cd and Zn in the clams were 1.8 to 4.7 and 1.1 to 1.9 times ...

2000-06-01

45

Environmental risk assessment. A method for determination and evaluation of the risks of harmful changes in air, water and soils due to hazardous substances which are handled in technical facilities - aspects which are relevant to the Environmental Liabilities Law. Die Beurteilung von Umweltrisiken. Eine Methode zur Ermittlung und Bewertung der Risiken einer schaedlichen Veraenderung der Umweltmedien durch umweltgefaehrdende Stoffe in technischen Anlagen unter dem Aspekt des Umwelthaftungsgesetzes  

Energy Technology Data Exchange (ETDEWEB)

The criterion the study is based on in evaluating environmental risks is the possibility of harmful changes in air, water and soils rather than the harmful environmental impacts these changes are caused by. The two significant criteria, i.e. the evaluated environmental hazards potentials or 'value parameters', and the evaluated damage-to-the-environment probabilities or 'safety parameters', reveal the respective environmental risks or 'risk factors'. These risk factors are classified by 23 environmental risk parameters for differentiation between low-risk and high-aid for pollution abatement measures provided that one fixes acceptance limits for the environmental parameters. As a rule the environmental risks of technical facilities which handle hazardous materials can be evaluated appropriately and the results can be compared. (orig./HSCH).

1992-02-07

46

Responses of the toxic cyanobacterium Microcystis aeruginosa to iron and humic substances  

British Library Electronic Table of Contents (United Kingdom)

Iron is an essential element to marine biota. Different types of dissolved organic matter (DOM), such as humic substances have impacts on the marine coastal waters iron chemistry.The aim of the study was to examine how the presence of humic substances (both aquatic and sedimentary) may affect iron bioavailability to the bloom-forming cyanobacterium Microcystis aeruginosa Kutzing incubated on standard and modified mineral BG-11 media. The final iron concentrations in the growth media ranged from 0.1 to 100mM.The results demonstrate that both the growth rate and the concentration of chlorophyll a in cultures of M. aeruginosa are limited by insufficient (a 15-fold as compared with the cultures exposed to iron only at the same concentration. Sedimentary humic acids in the presence of iron at a...

2007-01-01

47

How microcystin-degrading bacteria express microcystin degradation activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Alkali tolerance and the mechanism of microcystin (MC) degradation were investigated in the MC-degrading bacterial species, Sphingopyxis sp. C-1, to better understand the increased MC degradation under the alkaline conditions that arise during the disappearance of water blooms. MC-degrading bacteria harbour mlrA, mlrB and mlrC that encode MC-degrading enzymes. Sphingopyxis sp. C-1 also possesses these genes, as well as the mlrD gene that has been assumed to encode MC and its degradation transporter. This study demonstrated that MC degradation activity was promoted by the intermittent addition of microcystin-LR (MCLR) to cultures of strain C-1. That the expression of mlrA, mlrB and mlrC is induced by MCLR also was indicated, whereas that of mlrA and mlrB is induced by the MCLR degr...

2011-01-01

48

Upholding the Convention on the Rights of the Child: A Quandary in Cyberspace  

Science.gov (United States)

Put in place to protect the rights of the child, the Convention on the Rights of the Child is a set of non-negotiable standards. A core principle underpinning the Convention is the child's right to participate fully in social arenas and to access sources of social support without excessive interference. Juxtaposing this is the right of the child to be shielded from harm, abuse and exploitation. Over the past several decades the Internet has emerged as a fast and easily accessible medium for people to connect and communicate. While the Internet provides children with a source of support through chat rooms, online communities and social networking sites, just as equally it can expose vulnerable children to predatory and deviant individuals exacerbating the potential for harm. Upholding the Convention in cyberspace is a challenge. The Internet is not owned or regulated by any governing body and accountability is difficult to enforce. This article ...

2010-04-01

49

Robotics: Growing maintenance option for utilities  

International Nuclear Information System (INIS)

The use of robots in powerplants is an option that can no longer be ignored. Robots can reduce worker exposure to harmful environments and minimize downtime. As a result, electric utilities are using them more than ever. As robots become more widely accepted, more are being developed to handle an expanding variety of applications. This report begins with an overview of the use of robotics in the electric-utility industry; following that are sections detailing applications for nuclear plants, fossil-fired stations, and transmission and distribution facilities.

50

Radiation higienization possibility and perspectives  

International Nuclear Information System (INIS)

Food irradiation is the process of exposing food to an ionizing energy to kill harmful bacteria and other organisms and extend shelf-life. It is a safe process and has been approved by some 50 countries worldwide and applied commercially in the USA, Japan, China and several European countries for many years. Trends law regulations and new applications in Europe and another countries has been described. (author)

2005-09-07

51

Ozone layer  

Energy Technology Data Exchange (ETDEWEB)

Governments around the world will soon make decisions on policies that could determine the fate of the ozone layer-the Earth's shield from harmful ultraviolet radiation. The Vienna Convention for the Protection of the Ozone Layer, signed on March 22, 1985, created a framework for scientific cooperation and information exchange that will form the basis for a protocol for controlling substances thought to threaten the ozone layer. As of mid-1987, 29 countries had signed the Convention, including the major producers and users of chlorofluorocarbons (CFCs), the most important of suspect chemicals.

1987-12-01

52

Harm to the cell and harm to the individual  

International Nuclear Information System (INIS)

Exposures from most natural and artificial sources, with the exception of those from medical radiology, are received at average dose rates of only a few microsieverts a day. Such risks as may be caused by these exposures are most unlikely to be determined with precision directly by epidemiological studies of populations exposed at these low rates. They may, however, be reliably inferred from the observed risks of exposure to rather larger doses delivered at higher dose rates in the light of the increasing knowledge of the phenomena involved in the initial cellular damage, the extent to which such damage is incorrectly repaired, and the processes which intervene between the genetic or other harm to cells and the likelihood of its final expression in inherited abnormality, in cancer development, or in defective foetal or embryonic growth. Current studies are of great importance, therefore, in examining the circumstances in which coding sections of the chromosomal DNA ...

1983-04-11

53

Enzyme discovery in hybrid aspen for fibre engineering  

Environmental Research Database

DescriptionEnzymes are natural catalysts that are used increasingly to replace environmentally harmful chemicals and to achieve better catalytic selectivity during pulp and paper processing. The main objective of this project is to identify novel plant enzymes for deeper understanding of the process of fibre formation and for future improvement of the quality parameters of wood fibres. Specific modification of the fibre characteristics will facilitate their use as raw materials for the current pulp and pap [continued...

2005-01-31

54

Effects of electromagnetic pollution on human health discussed  

Energy Technology Data Exchange (ETDEWEB)

The harmful effects of high-intensity electric fields on human beings are discussed. Formulas for determining the field strength of high voltage transmission lines and track lines and experimental data of these effects on mice are given. Protective measures from these hazards are introduced. 18 references, 7 figures, 5 tables.

1982-01-01

55

Reduction of cadmium toxicity to green microalga Stichococcus bacillaris by manganese  

Energy Technology Data Exchange (ETDEWEB)

Investigations of cadmium toxicity to microorganisms are now more concerned with the interactions of cadmium with different environmental factors and other metals. The interactions are complex and have not been thoroughly studied yet. Metal interactions may assume the form of synergism characterized by increase in toxicity, but also of antagonism in which one metal reduces the toxicity of another. Apart from cadmium interactions with such toxic metals as mercury and lead, interactions of cadmium with the essential trace elements seem to be very interesting because it has been assumed that algal cells take up cadmium by the system transporting these elements. A previous study showed that cadmium transport into Stichococcus bacillaris cells was inhibited by Mn/sup 2 +/ ions. Thus, it can be supported that there exist some possibilities of using those ions antagonistic to cadmium as counterposition. Showing those possibilities was the aim of the present paper.

1988-12-01

56

Photodynamic therapy against cyanobacteria  

British Library Electronic Table of Contents (United Kingdom)

This study explores the use of photosensitizers and reactive oxygen species (ROS) to limit growth of cyanobacteria. We chose 12 phthalocyanines, tetraphenol porphyrine, and methylene blue as compounds producing singlet oxygen. Hydrogen peroxide was chosen as another source of ROS. These compounds were tested using algal toxicity tests in microplates on three cultures of green algae (Pseudokirchneriella subcapitata, Scenedesmus quadricauda, and Chlorella kessleri) and on three cultures of cyanobacteria (Synechococcus nidulans, Microcystis incerta, and Anabaena sp.). Results indicate that photosensitizers and singlet oxygen could be highly toxic for some selected phytoplankton species. Green alga Scenedesmus quadricauda was highly sensitive (EC50 = 0.07 mg/L) to compounds producing singlet o...

2007-01-01

57

Nucleomorph Ribosomal DNA and Telomere Dynamics in Chlorarachniophyte Algae  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT. Chlorarachniophytes are enigmatic marine unicellular algae that acquired photosynthesis by secondary endosymbiosis. Chlorarachniophytes are unusual in that the nucleus of the engulfed algal cell (a green alga) persists in a miniaturized form, termed a nucleomorph. The nucleomorph genome of the model chlorarachniophyte, Bigelowiella natans CCMP621, is 373 kilobase pairs (kbp) in size, the smallest nuclear genome characterized to date. The B. natans nucleomorph genome is composed of three chromosomes, each with canonical eukaryotic telomeres and sub telomeric ribosomal DNA (rDNA) operons transcribed away from the chromosome end. Here we present the complete rDNA operon and telomeric region from the nucleomorph genome of Lotharella oceanica CCMP622, a newly characterized chlorarachn...

2010-01-01

58

MULTICOMPONENT SEISMIC ANALYSIS AND CALIBRATION TO IMPROVE RECOVERY FROM ALGAL MOUNDS: APPLICATION TO THE ROADRUNNER/TOWAOC AREA OF THE PARADOX BASIN, UTE MOUNTAIN UTE RESERVATION, COLORADO  

Energy Technology Data Exchange (ETDEWEB)

This report describes the results made in fulfillment of contract DE-FG26-02NT15451, ''Multicomponent Seismic Analysis and Calibration to Improve Recovery from Algal Mounds: Application to the Roadrunner/Towaoc Area of the Paradox Basin, Ute Mountain Ute Reservation, Colorado''. Optimizing development of highly heterogeneous reservoirs where porosity and permeability vary in unpredictable ways due to facies variations can be challenging. An important example of this is in the algal mounds of the Lower and Upper Ismay reservoirs of the Paradox Basin in Utah and Colorado. It is nearly impossible to develop a forward predictive model to delineate regions of better reservoir development, and so enhanced recovery processes must be selected and designed based upon data that can quantitatively or qualitatively distinguish regions of good or bad reservoir permeability and porosity between existing well control. ...

2003-07-10

59

Effects of allelochemicals produced by one population in a chemostat-like environment  

British Library Electronic Table of Contents (United Kingdom)

In this paper, we study some general models suggested to describe the effects of chemical compounds produced by an algal population on its survival in a chemostat-like environment. The conditions for its persistence and extinction are found. In particular, in the first model we make very general assumptions to represent the uptake, the regulative and the inhibiting functions, and analyze its global stability completely. In the second one we specify the first two functions and leave general the third one. Here the regulative function has different property from that in the first model, and a saddle-node bifurcation phenomenon occurs. In addition, according to the experimental data reported in DellaGreca et al. [2010. Fatty acids released by Clorella vulgaris and their role in interference w...

2011-01-01

60

Allelochemicals produced by Caribbean macroalgae and cyanobacteria have species-specific effects on reef coral microorganisms  

British Library Electronic Table of Contents (United Kingdom)

Coral populations have precipitously declined on Caribbean reefs while algal abundance has increased, leading to enhanced competitive damage to corals, which likely is mediated by the potent allelochemicals produced by both macroalgae and benthic cyanobacteria. Allelochemicals may affect the composition and abundance of coral-associated microorganisms that control host responses and adaptations to environmental change, including susceptibility to bacterial diseases. Here, we demonstrate that extracts of six Caribbean macroalgae and two benthic cyanobacteria have both inhibitory and stimulatory effects on bacterial taxa cultured from the surfaces of Caribbean corals, macroalgae, and corals exposed to macroalgal extracts. The growth of 54 bacterial isolates was monitored in the presence of l...

2011-01-01

 
 
 
 
61

Ability of a ?minimum?? microbial food web model to reproduce response patterns observed in mesocosms manipulated with N and P, glucose, and Si  

British Library Electronic Table of Contents (United Kingdom)

We compared an idealised mathematical model of the lower part of the pelagic food web to experimental data from a mesocosm experiment in which the supplies of mineral nutrients (nitrogen and phosphorous), bioavailable dissolved organic carbon (BDOC, as glucose), and silicate were manipulated. The central hypothesis of the experiment was that bacterial consumption of BDOC depends on whether the growth rate of heterotrophic bacteria is limited by organic-C or by mineral nutrients. In previous work, this hypothesis was examined qualitatively using a conceptual food web model. Here we explore the extent to which a ?simplest possible?? mathematical version of this conceptual model can reproduce the observed dynamics. The model combines algal?bacterial competition for mineral nutrients (phosphor...

2007-01-01

62

Marine pastures: a by-product of large (100 megawatt or larger) floating ocean thermal power plants. Progress report, February 1, 1976--April 30, 1976  

Science.gov (United States)

Computer programs have been developed to define the temperature increase which would be needed to bring deep-ocean water into density equilibrium with surface water for locations where data are available. A series of continuous-flow studies on phytoplankton blooms resulting from mixtures of 80 percent deep and 20 percent surface water in 2000-liter concrete culturing vessels (''reactors'') has been completed. A quantitative determination of nutrient utilization and flow through a combined primary and secondary trophic level system has been completed. This study utilized the clam Tapes semidecussata, fed from phytoplankton grown in 80 percent deep and 20 percent surface water. An analysis of the fate of the deep water discharged from a floating OTEC plant indicates that horizontal containment of the resulting deep water: surface water mixture is necessary if conditions optimal for open-sea mariculture are to obtain. The design of ...

1976-01-01

63

Understanding the distribution and architecture of algal mound reservoirs through outcrop-based high-resolution sequence stratigraphy: An example from the paradox basin, USA  

Energy Technology Data Exchange (ETDEWEB)

An outcrop-based study combining detailed lithofacies analysis with high-resolution sequence stratigraphy in the Paradox Basin, southwestern United States. has shown that complex lateral and vertical facies variations occur in relatively consistent and predictable patterns. Large-scale facies shifts of several kilometers occur across major sequence boundaries whereas small-scale lateral and vertical variations develop from stacking of individual cycles. Understanding of vertical stacking patterns and lateral distribution of facies in outcrop can be directly applied to both three-dimensional distribution of reservoir facies in the subsurface as well as the evaluation of heterogeneity within individual reservoirs. The Desert Creek and Ismay intervals of the Paradox Formation (Pennsylvanian) exposed along the San Juan River in southeastern Utah are characterized by high-frequency cyclic repetition of carbonate and siliciclastic facies controlled primarily by 4th and 5th-order changes in ...

1995-08-01

64

Global climate change response program. Part 1. Potential effects of global change on chlorophyll alpha concentrations in a southwestern desert reservoir: Las Vegas Bay, Lake Mead, Nevada. Part 2. Simulated impacts of a double CO2 climate on the location of the thermocline in Lake Mead, Nevada. Final report  

Energy Technology Data Exchange (ETDEWEB)

Three algal bioassay experiments were conducted from March 1992 through September 1993 in an area of Lake Mead that has experienced problems associated with severe nutrient enrichment. The first experiment determined the effects of elevated CO2 (700 ppm) (2xCO2), vs ambient CO2 on the natural algal assemblage without nutrient enrichment. The second experiment determined the effects of 2xCO2 on nutrient enriched bioassays and if nutrients were limiting. The third experiment examined elevated temperatures and 2xCO2. Nested climate models were used to predict changes in water temperatures and thermocline development in Las Vegas Bay. The lake model predicted an increase in mean water temperatures of 1.8 deg under a 2xCO2 scenario. A thermocline definition of 1 deg. C change per 2-m depth was applied to water temperatures developed by a lake model coupled to nested general circulation and regional-scale atmospheric models in 3-year simulations of ...

1997-01-01

65

Low dose effects - is the fear more dangerous than the radiation?  

Energy Technology Data Exchange (ETDEWEB)

The use of hypothesis which assumes a dose / harmful effect relationship without a limit allows the calculation of risks attributable to doses too small to produce detectable, harmful biological effects. The daughter product of this hypothesis is ALARA concept which requires that the dose received is kept as low as reasonably achievable. This concept of prudent avoidance is generally accepted by international radiation protection organisations and universally applied by radiation health professionals. The acceptance of a hypothesis which assumes that a single nuclear event can cause carcinogenesis, has generated levels of anxiety which may have resulted in significant detriment to those possibly exposed to ionising radiation. The anxiety generated may have caused more detriment and a higher death rate than the worst case ` theoretical` value calculated using the Linear or Quadratic Linear Hypothesis. Information selected from reports and ...

1996-01-01

66

Post-transplant monitoring of renal allografts: are we there yet?  

British Library Electronic Table of Contents (United Kingdom)

Transplantation has emerged as the therapy of choice for many patients with end organ failure. One of the major goals is to tailor immunosuppressive therapy to the individual needs of every patient to balance the risk for rejection and over-immunosuppression. This will require diagnostic tools that can detect harmful processes in the allograft early, and that can be measured repeatedly. This review will consider recent advances in our understanding of the molecular nature of these processes and how this information is being utilized to design novel diagnostic assays to non-invasively monitor allografts. Highlighted is the need for large-scale prospective multi-centre studies to validate assays that show early promise in single centre studies.

2009-01-01

67

Rethinking maternal-fetal conflict: gender and equality in perinatal ethics.  

Science.gov (United States)

Practitioners who care for pregnant women face dilemmas when their patients use illicit drugs, reject medical recommendations, or cause fetal harm. Many ethics scholars characterize those situations as maternal-fetal conflicts. In conflict-based models, maternal rights are considered to conflict with fetal rights, or moral obligations owed to pregnant women are considered to conflict with those owed to their fetuses. I offer an alternative model of pregnancy ethics by applying relational and equality-based moral theories to situations of fetal harm by pregnant women. In this model, clinicians faced with ethical dilemmas should attempt to understand pregnant women and their decisions within their broad social networks and communities, ask how the clinician's personal standpoint influences outcomes judged to be ethical, and determine whether the clinician's ethical formulations reduce or enhance existing gender, class, or racial inequality. This ...

2000-11-01

68

Potential biogas scrubbing using a high rate pond  

Energy Technology Data Exchange (ETDEWEB)

The potential to scrub biogas in a high rate pond (HRP) was evaluated using apparatus designed to maximize gas-liquid contact. Experiments compared the removal of carbon dioxide from synthetic biogas by an 'in-pond angled gutter' to that by a simulated 'counter-current pit'. Results showed that the counter current pit has potential for use in biogas scrubbing, with synthetic biogas carbon dioxide composition consistently reduced from 40% to<5%. The in-pond angled gutter was less effective due to bubble coalescence which reduced the total bubble surface surface area available for gas transfer. Measurement of oxygen levels in the scrubbed biogas showed that despite supersaturation of oxygen in the HRP water, there was little transfer to the biogas, so that explosive methane/oxygen mixtures would not be formed. Theoretical calculations indicated that the amount of biogas likely to be formed during anaerobic treatment of municipal wastewater could ...

2005-07-01

69

Phytoplankton primary production in a eutrophic cooling water pond  

Energy Technology Data Exchange (ETDEWEB)

The effect of longer ice-free periods on the seasonal variation and total annual values of phytoplankton primary production was considered along with the efficiency and productivity of the phytoplankton communities at different water temperatures by constant light. The studied pond, Vasikkalampi, is located in the town Jvyaskyla in central Finland. The pond is slightly eutrophic and its water is used for cooling purposes by a 35 MW thermal powerplant. The cooling water is taken in the middle of the pond and it returns as heated effluent to the northern part, near the surface, about 100 m from the intake pipe. This circulation and warming of the water keeps the pond open throughout the year except during the coldest weeks in the winter when some parts freeze over. The increase of the water temperature was not sufficient to be optimal for photosynthesis in the spring. The phytoplankton biomass starts to increase early in the spring when the zooplankton grazing pressure is still low and ...

1984-01-01

70

Changes in aerobic digester performance with the use of methanol for biological nutrient removal in a full-scale sequencing batch reactor  

Energy Technology Data Exchange (ETDEWEB)

Increasingly, governments enact more stringent regulations governing nitrogen and phosphorus in the discharge effluent of wastewater treatment plants. Scientists know that nitrogen and phosphorus accelerates the eutrophication of lakes and reservoirs and stimulates algal growth. Ammonia has proven to be toxic to aquatic life forms, including fish. Engineers favour Biological Nutrient Removal (BNR) over chemical addition to wastewater treatment. Sequencing Batch Reactors (SBRs), a type of bioreactor requiring less land, provide the anaerobic, anoxic, and aerobic zones necessary for BNR. Methanol was used as an effective external source of carbon for denitrification but lacked research. The authors remedied this situation and some of the results were available. They indicated that the addition of methanol in the SBR increased solids production in the SBR, leading to increased sludge wasting to the aerobic digester. All aspects of the sludge digester performance that ...

2000-07-01

71

An assessment of metal contamination along the Irish coast using the seaweed Ascophyllum nodosum (Fucales, Phaeophyceae)  

Energy Technology Data Exchange (ETDEWEB)

The relative abundance and variation of Cr, Co, Cd and Pb in Ascophyllum nodosum and intertidal surface sediments from six locations around the coast were assessed over six seasons. Higher Cd and Pb levels in Galway Docks and Cork Harbour were attributed to localised inputs of these metals from municipal and domestic waste, while at a reference site (Ballyconneely), high algal Cr concentrations were considered a function of geological setting rather than anthropogenic loading. Little seasonal variation was observed, with the exception of higher Co levels in plants in winter, associated with growth dynamics and increased fluvial inputs. In comparison with previously published data for metals in A. nodosum from the North Atlantic, with the exception of localised hot spots, the Irish coastline is still a relatively pristine environment. A. nodosum may be successfully and easily used as a biomonitor of metal contamination in coastal waters. - This paper provides ...

2008-03-15

72

Action Potentials in a Giant Algal Cell: A Comparative Approach to Mechanisms and Evolution of Excitability  

Science.gov (United States)

The giant alga Chara corallina generates action potentials (APs) in response to mechanical stimulation, injury, or direct electrical stimulation. Students examine the waveform characteristics of these APs using standard intracellular recording techniques. Intracellular recording is easier than with neurons because of the large size of the Chara cell. Students observe very negative resting potentials (up to -250 mV), large AP amplitudes with depolarizing peaks approaching 0 mV, AP durations of seconds, and refractory periods up to several minutes. Students calculate Nernst potentials for the ions distributed across the Chara cell membrane to hypothesize the ions responsible for the resting potential and for the depolarizing phase of the AP. These calculations suggest that K+ is responsible for the resting potential and that Ca2+ influx and Ca2+-activated Cl- efflux are responsible for depolarizing phases of the AP, which they are. Comparison of the Chara AP characteristics with animal ...

2008-06-11

73

Using robots for industrial processes on coal mine surfaces  

Energy Technology Data Exchange (ETDEWEB)

How to decide which mine surface tasks may be performed by industrial robots to improve productivity and working conditions is described. Charts are presented of the industrial tasks performed on the surface and how each task may be classified as light, average, difficult or very diffcult according to a defect criteria is explained (defective operations are those which involve, heavy, harmful, stressful or dangerous jobs). The results of these calculations are used to identify which operations are suitable for first introduction of robots since traditional automation methods cannot be used, e.g. various storage, loading and packaging tasks, coal selection, sorting and removal of foreign matter, provision of services such as food preparation, cleaning, etc. Robots may also be used to control automated operations that are monotonous and hazardous for human operators. It is envisaged that in the future computer programmed robots with artificial intelligence will ...

1987-01-01

74

Theoretical study of the non-steady discharge at atmospheric pressure in pin-plate system and its application for ozone production  

International Nuclear Information System (INIS)

In this paper as a result of the theoretical studies and a numerical simulation we presented the following main conclusions: (i) for humid air at increasing pressure of 1.0133 10"5 Pa until 5.0665 10"5 Pa ozone concentrations during 2 centre dot 10"-"3 s become higher in 22 times. This fact we clear with structure of ozone-production reactions. In this case the harmful NO_x concentrations are 2-3 order lower than ozone one; (ii) it is shown that nitrogen is useful to ozone production in the discharge; (iii) based on ion collection we cleared increasing ignition discharge voltage at growing ozone concentrations even with low ozone concentrations.

75

The novel 'OLGA' technology for complete tar removal from biomass producer gas  

Energy Technology Data Exchange (ETDEWEB)

A new process for the removal of tar from biosyngas, OLGA (Oil and Gas Washer), is presented. This gas cleaning technology is based on physical principles and is designed to eliminate tar problems that relate to fouling and er pollution. The applied principles are confirmed by experimental validation. OLGA can be operated without suffering from harmful effects on important gasification characteristics as cold gas efficiency, gasifier simplicity, and feedstock flexibility. Some fundamental considerations in the development of OLGA are discussed. Amongst these is a different approach to the tar problem. This approach does not consider the total tar content as decisive in the evaluation of gas cleaning equipment. Instead, evaluation is focussed on whether tar properties as condensation behaviour and water solubility can still occur. A biosyngas free of tar should therefore be synonymous to a biosyngas that is free of tar related problems.

2002-10-14

76

Technology assessment: Chlorine chemistry  

International Nuclear Information System (INIS)

Chlorine is not just one of many chemical feedstocks which is used in a few definitely harmful products like PVC or CFC but is irrelevant in all other respects. Just the opposite is true: There is hardly any product line of the chemical industry that can do without chlorine, from herbicides and pesticides to dyes, plastics, pharmaceuticals, photographic atricles, and cosmetics. Chlorine is not only a key element of chemical production but also an ubiquitous element of everyday life in civilisation. There are even many who would agree that the volume of chlorine production is an indicator of the competitive strength and national wealth of a modern society. By now, however, it has become evident that the unreflected use of chlorine is no longer ecologically acceptable. The consequences of a chlorine phase-out as compared to the continued chlorine production at the present level were investigated scientifically by a PROGNOS team. They are presented in this book. ...

77

Risk assessment for radiation protection purposes  

International Nuclear Information System (INIS)

In defining criteria for good protection against ionizing radiation, it is important to assess quantitatively the likely risk of any radiation exposure. The 'somatic' risks to the individual result mainly from induction of cancer in the organs irradiated, and these risks can now be estimated on the basis of numerous detailed epidemiological surveys of exposed human populations. Estimates of the risk of hereditary effects, from genetic changes induced in germ cells, are based largely on the frequency with which such effects are induced in other species. In both cases the risk at very low dose can be inferred using knowledge of the way in which radiation damage is caused in tissues. Coherent systems of radiation protection are based on a restriction of doses to the whole body and to individual organs, such that the induction of cancer and genetic harm is infrequent, and the threshold dose for causing other, 'non-stochastic', effects is not exceeded. (author).

1980-01-01

78

Radio cellular phones and health: Up-to-date research on human health; Radiotelephones cellulaires et sante: mise au point des recherches portant sur la sante chez l'homme  

Energy Technology Data Exchange (ETDEWEB)

Cellular telephones emit a radiofrequency electromagnetic field, part of which is absorbed in the user's head. Many studies have been conducted to look for their possible health hazard to human, at the experimental, epidemiological or clinical level. After a short recall on dosimetry, the author describes the state-of-the art about harmful and irreversible effects, up to now not confirmed, and about some benign symptoms which look absolutely actual. A causal relationship of the electromagnetic field on these benign symptoms is however not proven; other, studies are running to evaluate their possible long-term consequences. Interferences with cardiac pacemakers can easily be avoided by holding the telephone handset farther than 10 cm. (author)

1999-12-01

79

Potential Protection of Green Tea Polyphenols Against 1800?MHz Electromagnetic Radiation-Induced Injury on Rat Cortical Neurons  

British Library Electronic Table of Contents (United Kingdom)

Radiofrequency electromagnetic fields (EMF) are harmful to public health, but the certain anti-irradiation mechanism is not clear yet. The present study was performed to investigate the possible protective effects of green tea polyphenols against electromagnetic radiation-induced injury in the cultured rat cortical neurons. In this study, green tea polyphenols were used in the cultured cortical neurons exposed to 1800?MHz EMFs by the mobile phone. We found that the mobile phone irradiation for 24?h induced marked neuronal cell death in the MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and protective effects of green tea polyphenols on the injured cortical neurons were demonstrated by testing the content ...

2011-01-01

80

Point defects in dilute nitride III-N-As and III-N-P  

International Nuclear Information System (INIS)

We provide a brief review of our recent results from optically detected magnetic resonance studies of grown-in non-radiative defects in two most important dilute nitride systems-Ga(In)NAs grown on GaAs substrates and Ga(Al,In)NP grown on Si and GaP substrates. These results have led to the identification of defect complexes in the alloys, involving intrinsic defects such as As_G_a antisites and Ga_i self-interstitials. They have also shed light on formation mechanisms of the defects and on their role in non-radiative carrier recombination that is harmful to the performance of potential optoelectronic and photonic devices based on these dilute nitrides.

2006-04-01

 
 
 
 
81

Photoelectron resonance capture ionization mass spectrometry of fatty acids in olive oil  

British Library Electronic Table of Contents (United Kingdom)

Photoelectron resonance capture ionization (PERCI) mass spectrometry has been developed for the direct online analysis of organics, including lipids. Analysis is conducted without the need for sample preparation or chemical derivatization such as methylation, foregoing the use of harmful or toxic chemicals. PERCI is currently being adapted towards the analysis of edible oils. Herein, as a proof of principle of the simplicity and potential utility of this method towards the analysis of edible oils, we present the analysis of the prevalent fatty acids (FA) in Tuscan extra-virgin olive oil along with triolein and linolenic acid (LNA) standards. Ionization of olive oil results in little fragmentation of the prevalent FA, which are measured as their molecular ions, [FA-H]-. The relative concent...

2006-01-01

82

OES receives permit for remediation of PCB contaminated soils  

Energy Technology Data Exchange (ETDEWEB)

Ogden Environmental Services has announced that the Environmental Protection Agency (EPA) has issued a nation-wide federal permit allowing OES to use its circulating bed combustion (CBC) system for remediation of PCB contaminated soils. The landmark permit confirms the effectiveness of OES' CBC system and its ability to destroy PCBs without releasing harmful quantities of PCBs or other chemicals into the air. EPA headquarters issued the permit following their audit of trial burn operations of OES' CBC unit during September 1988 at the Arco Swanson River oil fields in the Kenai Wildlife Refuge, Kenai Peninsula, Alaska. The Arco project represents the world's first major remediation program using CBC technology and the largest PCB/soil cleanup to date.

1989-08-01

83

Loyal but ignored: The benefits and costs of constructive communication behavior  

British Library Electronic Table of Contents (United Kingdom)

The consequences of exit, voice, loyalty, and neglect behavior were examined using retrospective questionnaires (Study 1) and 2 social interaction diary studies (Study 2). Exit and neglect were generally associated with more negative partner responses and reduced feelings of value and closeness, and were reported to be more harmful to the relationship. Voice was associated with more positive partner responses and greater value and intimacy, and was perceived to be most beneficial to the relationship. In contrast, loyalty was perceived to have the same detrimental consequences as destructive behaviors (Study 1) and did not predict more positive outcomes within daily interactions (Study 2). These results indicate that, despite good intentions, loyal intimates are often left feeling ignored a...

2010-01-01

84

Eluates from pyrolysed refuse. Eluate aus pyrolysiertem Hausmuell  

Energy Technology Data Exchange (ETDEWEB)

The solubility behavior of solid residues from the heat treatment of domestic rubbish was examined by simulated precipitation in laboratory lysimeters. The precipitation corresponded to the average amount of rain in West Germany and was applied at different time periods. Specific soil characteristics, the value of k/sub f/ and the water retention capacity was determined in this way. In parallel with the lysimeter flood ions, extraction (by batch process) was done, in order to find the maximum solubility of the materials used. It was found that for pyrolysis residues from reactor temperatures of 450/sup 0/ to 1000/sup 0/C, a greater solubility was measured than for slag from combustion. The eluates from these residues gave information about the degree of contamination or on the solubility of the measured parameters and materials in organoleptic, physical, organic and inorganic examinations. The concentrations of harmful substances in the eluates pointed to the ...

1981-01-01

85

Effects of C-60 fullerenes and carbon nanotubes on marine mussels.  

Environmental Research Database

Objectives1. We will use reduction of lysosomal stability as an indicator of cell injury induced by C-60 fullerenes and carbon nanotubes in the liver analogue or digestive gland (hepatopancreas) of marine mussels. Molluscan hepatopancreatic digestive cells are key to normal function and are a sensitive key interface with the environment. Reduction of lysosomal stability is mechanistically linked with impaired health of the whole animal. 2. We will also test the hepatopancreatic digestive cells for evide [continued...]DescriptionNanotechnology is a major innovative scientific and economic growth area, which may present a variety of hazards for environmental and human health. The surface properties and very small size of nanoparticles and nanotubes provides surfaces that may bind and transport toxic chemical pollutants, as well as possibly being toxic in their own right by generating reactive oxygen species (ROS). There is a wealth of evidence for the harmful effects ...

2008-01-25

86

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants.  

Science.gov (United States)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distribution of stable iodine tablets is advised. PMID:20332130

2010-03-23

87

Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants  

British Library Electronic Table of Contents (United Kingdom)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distrib...

2010-01-01

88

Determination and removal of malondialdehyde and other 2-thiobarbituric acid reactive substances in waste cooking oil  

British Library Electronic Table of Contents (United Kingdom)

Waste cooking oil can be recovered and processed into animal feed additives after purification. Unfortunately, the traditional purification processes are insufficient for the removal of the harmful compounds formed during frying, mainly about malondialdehyde and other 2-thiobarbituric acid reactive substances. In the present paper, firstly, a simple and reliable HPLC method was developed to measure the content of malondialdehyde in purified waste cooking oil. The detection limit and the standard recovery of the analysis method are 1.20x10-5gl-1 and 96.5-99.2%, respectively, which is accurate and valid enough for the detection of malondialdehyde in waste cooking oil. Furthermore, the removal of malondialdehyde and other 2-thiobarbituric acid reactive substances from waste cooking oil was in...

2011-01-01

89

Detection of irradiated chicken by ESR spectroscopy of bone  

Energy Technology Data Exchange (ETDEWEB)

Ionizing radiation has been used to treat poultry to remove harmful microorganisms, mainly Salmonella, which contaminates chicken, goose and other fresh and frozen poultry. This microorganism is sensitive to low dose radiation. Thus, irradiating these foods with doses between 1 to 7 kGy results in a large reduction of bacteria. Since it is necessary to determine whether irradiation has occurred and to what extend, this work studied the signal produced by ionizing radiation within the hard crystalline matrix of chicken`s bone to establish a control method. Chicken`s drumsticks were irradiated and bones separated from flesh were lyophilized and milled. ESR spectrum was then obtained. The ESR signal increased linearly with dose over the range 0.25 to 8.0 kGy. Free radicals evaluated during 30 days after irradiation showed stable in this period. (Author).

1995-10-01

90

Cumulative effect of X-ray radiation and inflammatory reaction on the circadian rhythm of tyrosine aminotransferase in the liver of mice  

International Nuclear Information System (INIS)

The activity of tyrosine aminotransferase (TAT) in the liver of mice subjected simultaneously to ionizing radiation and to local inflammatory process showed in the first 24 hours of the experiment statistically significant changes resulting from summation of the harmful effects of both factors. In the second 24-hour period an evident tendency was observed for return of a normal circadian rhythm of the enzyme. This points to presence of an endogenous mechanism of suppression of the manifestations of significant desynchronization of the circadian rhythm. The paper contains also a trial of mathematical analysis of changes in TAT activity in the circadian rhythm, a description and analysis or the suppression process, qualitative and quantitative determination of the phenomenon of cumulation of the effects of powerful stress factors acting on the animal organism. The obtained results were compared with the results of investigations of TAT activity changes obtained in ...

1980-01-01

91

Corrosion in steam generators of PWR type nuclear power plants  

International Nuclear Information System (INIS)

Problems are discussed of heat exchange tubes of Westinghouse type vertical steam generators exhibiting corrosion damage such as point corrosion, planar corrosion, tube denting, corrosion stress cracking, crevice corrosion, fretting corrosion and intergranular corrosion. Attention is also paid to problems of WWER-440 type horizontal steam generators, where the level fluctuation area is critical; noncompact porous deposits of the corrosion products give rise to crevice effects and cause significant concentration of chloride ions and other additions. This problem can be partly resolved by a modification of the collector design at the level variation area. An additional measure is the production of steel 08Kh18N10T with a very low level of harmful elements and inclusions. (Z.M.). 3 figs., 11 refs.

1988-03-01

92

Atrazine exposure leads to altered growth of HepG2 cells  

British Library Electronic Table of Contents (United Kingdom)

Atrazine is one of the most commonly used herbicides in the United States. While effective on target plants, it has been associated with harmful health effects in non-target organisms such as fish, amphibians and mammals. In this study, growth effects on human liver cells were determined after exposure to increasing concentrations of this herbicide. Growth of immortalized human hepatoma HepG2 cells was inhibited by atrazine concentrations of 625 ppb after 72 h exposure and flow cytometry analysis demonstrated HepG2 cells exposed to 100 ppb atrazine accumulated in S phase after 48 h compared to untreated cells. Expression of cell cycle specific cyclin proteins was altered after atrazine exposure with cyclin E levels significantly decreased after a 24 h exposure and cyclin B levels decreased...

2011-01-01

93

Application of nuclear analytical methods in determining heavy metals in a welder's working environment  

International Nuclear Information System (INIS)

The problems are discussed of using radionuclide X-ray fluorescence analysis (the most frequently used source is "2"4"1Am) and neutron activation analysis for monitoring the chemical quality of the working environment of a welder. Elements determinable by these methods are listed and the advantages of the methods stated with regard to speed, simplicity and appropriate accuracy of measurement together with commercial availability of the instruments. Welding as a source of harmful substances is assessed by determination of the amount of chromium in aerosols generated by welding austenitic chromium-nickel steels. The described methods allow to obtain a complex image of the chemical nature of welding aerosols and to understand the mechanism of their impact on the human organism. (J.C.).

1986-01-01

94

An assessment of health impacts of electrical power transmission lines  

International Nuclear Information System (INIS)

The types of investigations undertaken to test for possible biological effects of extremely low frequency electric fields have been numerous. However, neither animal and plant experimentation nor clinical studies nor experience with operating extremely high voltage transmission lines have to date provided convincing evidence of a harmful effect from exposure to electric fields associated with transmission lines in spite of numerous attempts to find such effects. Analysis of internal fields and currents supports these observations as the levels appear to be too low to affect mammalian cells. Thus, while one can never prove the negative (i.e. that there is no effect), the overwhelming body of evidence indicates that the electric fields associated with high-voltage lines have no deleterious biological effects. (author).

1981-06-26

95

A proof of concept study for a structure activity model for the toxicity of nanoparticles  

Environmental Research Database

ObjectivesThe development of novel formulations of nanoparticles in the nanotechnology industry and their increasing importance and use in industry means there is certainty of human environmental exposures in both the workplace and the general environment. The pulmonary route of exposure to airborne nanoparticles is a major one, as nanoparticles are handled in industry, escape from workplaces and products containing nanoparticles undergo attrition in the environment. There is a substantial problem for ris [continued...]DescriptionNanoparticles are extremely small particles, each individual particlel being less than one ten millionth of a metre in size. We are exposed to nanoparticles in busy streets as they are present in traffic exhaust produced from combustion of fuel and such nanoparticles are considered to be important in causing the harmful effects associated with exposure to air pollution. There are other situations where nanoparticles are found in the air, ...

2009-01-28

96

A general process-based mass-balance model for phosphorus/eutrophication as a tool to estimate historical reference values for key bioindicators, as exemplified using data for the Gulf of Riga  

British Library Electronic Table of Contents (United Kingdom)

This work describes how a general, process-based mass-balance model (CoastMab) for phosphorus for coastal areas may be used as a tool to estimate realistic values of "natural" or preindustrial reference levels of key bioindicators in coastal science, including the Secchi depth, a standard measure of water clarity, the chlorophyll-a concentration, an operational measure of phytoplankton biomass and the concentration of cyanobacteria, a measure of the concentration of harmful algae. The CoastMab-model is an ecosystem model giving monthly predictions to achieve seasonal variations of basin-wide properties. The selected case-study area, the Gulf of Riga, is sensitive to nutrient loading because of its shallowness and low openness towards the Baltic Proper. The morphometry of any coastal area, ...

2009-01-01

97

A Generic Impact-Scoring System Applied to Alien Mammals in Europe  

British Library Electronic Table of Contents (United Kingdom)

Abstract: We present a generic scoring system that compares the impact of alien species among members of large taxonomic groups. This scoring can be used to identify the most harmful alien species so that conservation measures to ameliorate their negative effects can be prioritized. For all alien mammals in Europe, we assessed impact reports as completely as possible. Impact was classified as either environmental or economic. We subdivided each of these categories into five subcategories (environmental: impact through competition, predation, hybridization, transmission of disease, and herbivory; economic: impact on agriculture, livestock, forestry, human health, and infrastructure). We assigned all impact reports to one of these 10 categories. All categories had impact scores that ranged f...

2010-01-01

98

Radiation effects on shoot tip culture of chrysanthemum, 2  

International Nuclear Information System (INIS)

(1) Young chrysanthemums were planted after being irradiated at the time of shoot tip culture and the influence of irradiation was evaluated from the point of view of establishment of mutants. (2) Two cultivars, Kin-tenryu and Tenryu-no-asa were used in this experiment. The percentage of cultivars healthy enough to transplant on June 10, 1972 showed a decrease in proportion to the increase of dosage. Some plants of cultivar Kin-tenryu died after being transplanted. (3) Few plants of either cultivar could overwinter, and in particular no plant irradiated by gamma-rays of 20 kR. (4) Plant height showed a tendency of inhibition in both cultivars. (5) Three chlorophyll mutants showing chimera appeared. One of them was in the cultivar Tenryu-no-asa irradiated by 10 kR at 3 days after planting; two of them were in the cultivar Tenryu-no-asa irradiated by 10 kR at 5 days after planting. One mutant exhibiting malformation of entire leaves appeared in the cultivar Kin-tenryu irradiated by 20 kR ...

99

Evaluation of the F_1 sterility technique for population suppression of the pink bollworm, Pectinophora gossypiella (Saunders)  

International Nuclear Information System (INIS)

Field cage studies were carried out to evaluate the F_1 sterility technique for population suppression of the pink bollworm, Pectinophora gossypiella (Saunders), in cotton. For this purpose, six field cages (1.8 m x 1.8 m x 1.8 m) were placed over cotton seedlings in the field. Five pairs of laboratory reared, untreated adult moths were released in all six cages during the first week of August. In addition, on the same data 100 pairs of adults, following irradiation of the mature pupae at 100 Gy, were released in two cages and 250 such pairs of irradiated adults in two other cages in ratios of 20:1 and 50:1 (irradiated:normal), respectively. The results of per cent larval infestation in the rosette blooms in different field cages indicated that larval infestation in the flowers was significantly lower (4.93%) in cages where the moths were released at the 50:1 ratio than in cages where moths were released at the 20:1 ratio (6.71%). Larval infestation in the flowers ...

1993-09-01

100

Application of continuous casting steel 100Cr6 (SAE 52100) for bearing balls  

Energy Technology Data Exchange (ETDEWEB)

The objective of the investigation was to study the feasibility of applying continuous casting steel 100Cr6 (SAE 52100) for bearing balls. It was found that two of three continuous casted steel batches have longer or at least similar rolling contact fatigue lifetimes compared to one ingot casted batch. For one of the continuous casted batches, the rolling contact fatigue lifetime was 30% less. The micro- and macrostructure and the residual stresses below the surface of the balls were comparable. There is also no obvious difference between the four batches in the metallurgical parameters like contents of oxygen, titanium and sulfur as well as in the distribution of carbides and their network. The reason for the shorter lifetime of one batch finally was found to be due not to the continuous casting process itself. There was a difference in the cross section of the different casting moulds, and by this in the speed of solidification. As a consequence an increased segregation of alloying ...

1998-12-31

 
 
 
 
101

Using the health belief model to predict injecting drug users' intentions to employ harm reduction strategies.  

Science.gov (United States)

We examined whether perceived susceptibility to and severity of two injection-related health conditions (i.e., non-fatal overdose and bacterial infections), and perceived benefits of, barriers to, self-efficacy to, social acceptance of, and recent use of two harm-reduction behaviors (i.e., injecting test shots and pre-injection skin cleaning), predicted injecting drug users' near-term intentions to engage in these two strategies. Recent past use of these two behaviors consistently and positively predicted near-term intentions in each of four drug-use situations (i.e., in withdrawal, not in withdrawal, alone, and with others). Perceived susceptibility to non-fatal overdose predicted intentions to do test shots, but only when participants imagined not being in withdrawal or injecting when alone. Perceived self-efficacy to clean one's skin predicted intentions to engage in this behavior, but only when participants imagined injecting while not in withdrawal. ...

2011-06-24

102

The performance tests used the water scrubber for ruthenium rejection  

Energy Technology Data Exchange (ETDEWEB)

LEDF (Large Equipment Dismantling Facility) will be constructed for the purpose of decontaminating the high level {alpha} solid waste generated in oarai engineering center of JNC. And, main processing process of LEDF is incineration and melting system. LEDF will be intended to reduce the secondary waste that occurs along with the operation of the off gas processing equipment of incineration and melting system. It assumed that we are able to eliminate the adsorption tower using silica gel, if the decontamination factor to volatile ruthenium is able to expect in the packed scrubber that is established to remove harmful gas. Thereupon, we carried out this tests that eliminates the adsorption tower and reduces the secondary waste. The decontamination factor (DF) to the volatile ruthenium by the water scrubber is confirmed in the established institution which is in Tokai Works. However, decontamination factor differs and depends on the ruthenium concentration, ...

2002-11-01

103

The performance tests used the water scrubber for ruthenium rejection  

International Nuclear Information System (INIS)

LEDF (Large Equipment Dismantling Facility) will be constructed for the purpose of decontaminating the high level #alpha# solid waste generated in oarai engineering center of JNC. And, main processing process of LEDF is incineration and melting system. LEDF will be intended to reduce the secondary waste that occurs along with the operation of the off gas processing equipment of incineration and melting system. It assumed that we are able to eliminate the adsorption tower using silica gel, if the decontamination factor to volatile ruthenium is able to expect in the packed scrubber that is established to remove harmful gas. Thereupon, we carried out this tests that eliminates the adsorption tower and reduces the secondary waste. The decontamination factor (DF) to the volatile ruthenium by the water scrubber is confirmed in the established institution which is in Tokai Works. However, decontamination factor differs and depends on the ruthenium concentration, ...

104

Social modeling in the transmission of suicidality.  

Science.gov (United States)

Evidence from twin, adoption, and family studies suggests that there is strong aggregation of suicidal behaviors in some families. By comparison, the role of social modeling through peers has yet to be convincingly established. This paper uses data from four large studies (the WHO/EURO Multicentre Study on Suicidal Behaviour, the WHO/SUPRE-MISS, the CASE study, and the Queensland Suicide Register) to compare the effects of exposure to fatal and nonfatal suicidal behavior in family members and nonfamilial associates on the subsequent suicidal behavior of male and female respondents of different ages. Across all studies, we found that prior suicidal behaviors among respondents' social groups were more important predictors of suicidal behavior in the respondents themselves than previous research had indicated. Community-based suicide attempters in the WHO SUPRE-MISS had higher rates of exposure to prior suicide in nonfamilial associates than in family members. In an adolescent population, ...

2008-01-01

105

Smog alarm. Five functions of special emergency measures. Smogalarm. Fuenf Funktionen der unmittelbaren Gefahrenabwehr im Umweltschutz  

Energy Technology Data Exchange (ETDEWEB)

Most environmental policies provide for special emergency measures to be taken during phases of high pollution, such as smog alarm regulations. These measures serve several purposes and can have various impacts. First of all, they act as a warning to those parts of the population immediately threatened by health hazards (Warnfunktion). They may be directed at short-term pollution reduction via pollution abatement measures proscribed during smog alarm situations (unmittelbare Steuerungsfunktion). In addition, the announcement of emergency measures may signal that pollution levels in general have been too high, indicating that the environmental policies normally pursued do not sufficiently or effectively protect human beings and the environment from harm (Signalfunktion). Emergency measures often contain special regulations obliging industrial polluters to switch to costly, less polluting production processes, or to stop production altogether. This may act as an ...

1985-01-01

106

Exposure of Finnish population to solar UV radiation and consequent carcinogenic effects  

Energy Technology Data Exchange (ETDEWEB)

Depletion of stratospheric ozone increases irradiance of terrestrial ultraviolet (UV) radiation at short wavelengths, which may be harmful to the human health. To understand quantitatively the risks caused by increasing UV radiation to the Finnish population, the actual UV exposure of the population has to be assessed. It was shown that the snow reflection increases the UV exposure to the face and eyes particularly in the northern Finland. In 1993 exceptionally low ozone levels persisted up to the end of May, which resulted in a theoretical increase in the annual UV dose ranging from 8 % to 13 % in Finland. The maximal increase in the measured erythemally effective dose rate was 34 % on 23 April, when compared with the theoretical normal value. During this study exposure models have been developed. The models have been combined them with Green`s radiation transfer model to estimate annual facial UV doses received by different groups of Finnish population. Also, an ...

1996-12-31

107

Concept of malignant significant factor and its applicability for and occupational exposures  

International Nuclear Information System (INIS)

In the medical and occupational exposures, there is a tradition to use the genetically significant dose as an index of harm to the population although it only includes the genetical effects from ionizing radiations. A similar significant dose for somatic effects such as radiation leukemogenesis and carcinogenesis should be added to the genetically significant dose in order to approach an index of total harm to the population from medical and occupational exposures. For this purpose, leukemia and malignant significant factors were determined based on the induction of malignant diseases including leukemia for the atomic bombs in Hiroshima and Nagasaki and the life expectancy of individuals subject to medical examinations or treatments as well as radiation workers, taking account of the possibility of their deaths due to other diseases or accidents during a latent period of malignant diseases. The resultant significant factors were tabulated as a ...

1980-01-01

108

Waste management plan for Phase II of the Bear Creek Valley treatability study Oak Ridge Y-12 Plant, Oak Ridge, Tennessee  

Energy Technology Data Exchange (ETDEWEB)

This Waste Management Plant (WMP) for the Bear Creek Valley Treatability Study addresses waste management requirements for the Oak Ridge Y-12 Plant. The study is intended to produce treatment performance data required to design a treatment system for contaminated groundwater. The treatability study will consist of an evaluation of various treatment media including: continuous column tests, with up to six columns being employed to evaluate the performance of different media in the treatment of groundwater; an evaluation of the denitrifying capacity and metal uptake capacity of a wetland system; and the long-term denitrifying capacity and metal uptake capacity of algal mats. The Sampling and Analysis Plan (SAP) covers the project description, technical objectives, procedures, and planned work activities in greater detail. The Health and Safety Plan (HASP) addresses the health and safety concerns and requirements for the proposed sampling activities. This WMP ...

1997-05-01

109

The carbonate feedback system: interaction between stratigraphic accommodation, ecological succession and the carbonate factory; Le systeme de feed-back des carbonates: une interaction entre accomodation stratigraphique, succession ecologique et l`usine des carbonates  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the analysis of carbonate depositional systems, using high resolution sequence stratigraphy, studies the ratio between change in accommodation space and skeletal carbonate production. This approach establishes the concurrent change in nature of facies belts (expansion, retraction and type) and fossil communities, within the detailed time frame in accommodation. Carbonate production is generally considered to be a fairly simple function of environmental conditions such as climate and water depth. However, data from several case studies also show a covariance between change in stratigraphic architecture of carbonate systems (the seaward or landward stepping stacking patterns of stratigraphic units) and charge in facies. Case studies include Carboniferous algal mound development in the Paradox Basin (USA), Devonian stromatoporoid reef development in Alberta (Canada), and Cenomanian rudistid shoal development in Oman. The hypotheses are tested on cases ...

1996-12-31

110

Solution and particle effects on the biosorption of heavy metals by seaweed biomass  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of cadmium (Cd), cobalt (Co), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) by six fractions of particle sizes, ranging from 0.063 to 1.4 mm of dry marine algal biomass of Sargassum fluitans and Ascophyllum nodosum, is examined. Equilibrium metal uptake by larger particles was higher than that by smaller particles in the order of Pb > Cd > Cu > Co > Zn > Ni for both biomass types, with S. fluitans sorbing slightly more than A. nodosum. Uptakes of metals ranged from the highest, q{sub max} = 369 mg Pb/g (particle size 0.84-1.00 mm), to the low Zn and Ni uptakes, q{sub max} = 77 mg/g (size 0.84-1.00 mm) for S. fluitans. A. nodosum adsorbed metals in the range from q{sub max} = 287 mg Pg/g (particle size 0.84-1.00 mm) to q{sub max} = 73 mg Zn/g (particle size 0.84-1.00mm). Harder stipe fractions of S. fluitans demonstrated generally higher metal uptakes than the softer fractions derived from its blades (leaves). The pH dependence of the ...

1996-12-01

111

Facies variation, diagenesis, and exploration potential of the Cretaceous rudist-bearing carbonates of the Arabian Gulf  

Science.gov (United States)

The Cretaceous rudist-bearing carbonates of the Arabian Gulf region are proven exploration targets for hydrocarbons and form the reservoirs of a number of giant fields, including Bu Hasa, Fateh, Fahud, Idd El Shargi, Rumaila, Shaybah, and Shah. Rudist buildups occur in three principal formations: (1) Aptian Shuaiba, (2) Cenomanian Mishrif, and (3) Maastrichtian Simsima. A regional subaerial unconformity marks the upper boundary of each of these formations. Associated with the rudists that dominate the Shuaiba Formation are calcareous algal crusts, foraminifera, and echinoid plates, which accumulated in mudstone, packstone, and carbonate sands. The Mishrif Formation contains mollusk fragments, bioclasitc packstones to grainstones, miliolid and nonrudist bivalves in muddy limestones, and rudist (mainly radiolitids and caprinids) conglomeratic floatstones, with fragmented rudists mixed with wackestone lithoclasts. The Mishrif sediments accumulated as a progradational, ...

1995-04-01

112

Depositional setting of the Upper Jurassic Hith Anhydrite of the Arabian Gulf: An analog to holocene evaporites of the United Arab Emirates and Lake MacLeod of Western Australia  

Energy Technology Data Exchange (ETDEWEB)

The Upper Jurassic Hith Anhydrite is a major hydrocarbon seal in the Arabian Gulf region. Outcrops, core samples from the subsurface, and the literature indicate that the Hith Formation is composed mainly of anhydrite. In most locations where a section of the Hith Formation has been measured, this unit contains less than 20% carbonate much of which is in the form of thin laminations. This lack of carbonate, locally thick layers of salt, and the predominance of anhydrite favor a playa for the setting in which this sediment was accumulated. In fact, much of the Hith has the sedimentary characteristics of the Holocene Lake MacLeod playa of Western Australia, which is dominated by layers of gypsum and halite (what little carbonate that occurs is found in layers at the base of the section). Locally the Hith appears to have accumulated in a sabkha setting, particularly toward central Abu Dhabi where it pinches out into shallow-water, and peritidal carbonate. This sabkha setting is indicated ...

1994-07-01

113

Burial dissolution and dolomitization relationships to moldic, stylolite and fracture porosity in the Cretaceous Sunniland Formation rudistid carbonate reservoir facies, Florida  

Energy Technology Data Exchange (ETDEWEB)

Cretaceous Sunniland Formation rudistid reservoir facies buried at 3,520 meters (92 C) between evaporite units contain marginally mature algal sapropelic carbonate source rock hydrocarbons. The closed system aids in identification of porosity redistribution related to hydrocarbon emplacement. Multiple dissolution and cementation events associated with hydrocarbon migration pulses are particularly evident along stylolites. Corrosion usually predates typically interparticle first generation saddle dolomite, and corroded saddle dolomite may be observed with two generations of optically continuous limpid overgrowths separated by a corrosive boundary. Dissolution or dedolomitization may provide a magnesium source for subsequent dolomite cements. Carbonic and organic acids are probable primary corrosive agents. Moldic, stylolite and fracture porosity, often reduced by dolomite cements, was generated. Moldic pores may develop from peloids by dissolution of peripheral ...

1994-03-01

114

Biosorption of hexavalent chromium by raw and acid-treated green alga Oedogonium hatei from aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

The hexavalent chromium, Cr(VI), biosorption by raw and acid-treated Oedogonium hatei were studied from aqueous solutions. Batch experiments were conducted to determine the biosorption properties of the biomass. The optimum conditions of biosorption were found to be: a biomass dose of 0.8 g/L, contact time of 110 min, pH and temperature 2.0 and 318 K respectively. Both Langmuir and Freundlich isotherm equations could fit the equilibrium data. Under the optimal conditions, the biosorption capacities of the raw and acid-treated algae were 31 and 35.2 mg Cr(VI) per g of dry adsorbent, respectively. Thermodynamic parameters showed that the adsorption of Cr(VI) onto algal biomass was feasible, spontaneous and endothermic under studied conditions. The pseudo-first-order kinetic model adequately describe the kinetic data in comparison to second-order model and the process involving rate-controlling step is much complex involving both boundary layer and intra-particle ...

2009-04-15

115

Use of boron waste as a fluxing agent in production of red mud brick  

Energy Technology Data Exchange (ETDEWEB)

The study was directed towards determining the usability of clay and fine wastes (CW and FW) of boron from the concentrator plant in Kirka (Turkey) as a fluxing agent in production of red mud (RM) brick. Both laboratory studies on the characterization of materials and industrial-scale tests for production of bricks were carried out. CW and FW, which have similar chemical composition but include different types and amounts of oxides, were added in amounts of 5, 10 and 15wt% to RM, which consists of high amounts of Fe{sub 2}O{sub 3}, Al{sub 2}O{sub 3}, SiO{sub 2} and alkalies. Six different sets of samples have been produced and fired at 700, 800 and 900{sup o}C. Dry shrinkage of green body, bending and compressive strength, firing shrinkage, water absorption, frost resistance and harmful magnesia and lime tests on heat-treated bodies have been performed. The mineralogical and mechanical tests showed that usability of boron wastes as a fluxing agent in the production ...

2006-12-15

116

Technological diffusion in industry: research needs and shortcomings. [Literature review for last 20 to 25 years  

Energy Technology Data Exchange (ETDEWEB)

Advances in technology are widely regarded as major sources of improvements in the competitive positions of firms and industries as well as of increases in national economic growth rates and standards of living. Because the benefits of such advances obviously depend on the extent to which they are utilized, considerable research has been focused on the diffusion of technological innovations. Most of these studies have sought to measure the dimensions of technological diffusion and to explain differences in diffusion patterns among innovations, industries, and nations as well as changes in such patterns over time. However, the most valuable contributions made so far have been to reveal the need for more-penetrating concepts, better measures, more-comprehensive analytical frameworks, and wider samplings of the variegated phenomena to be encompassed. Shortcomings in the theoretical work have seldom been directly harmful to industrial managements because they rely on ...

1981-03-01

117

Research progress in the electrochemical synthesis of ferrate(VI)  

International Nuclear Information System (INIS)

There is renewed interest in the +6 oxidation state of iron, ferrate (VI) (FeVIO42-), because of its potential as a benign oxidant for organic synthesis, as a chemical in developing cleaner ('greener') technology for remediation processes, and as an alternative for environment-friendly battery cathodes. This interest has led many researchers to focus their attention on the synthesis of ferrate(VI). Of the three synthesis methods, electrochemical, wet chemical and thermal, electrochemical synthesis has received the most attention due to its ease and the high purity of the product. Moreover, electrochemical processes use an electron as a so-called clean chemical, thus avoiding the use of any harmful chemicals to oxidize iron to the +6 oxidation state. This paper reviews the development of electrochemical methods to synthesize ferrate(VI). The approaches chosen by different laboratories to overcome some of the difficulties associated with the electrochemical synthesis ...

2009-04-01

118

Protocol to the 1979 convention on long-range transboundary air pollution on heavy metals; Aarhus, 24 June 1998  

Energy Technology Data Exchange (ETDEWEB)

The Executive Body adopted the Protocol on Heavy Metals on 24 June 1998 in Aarhus (Denmark). It targets three particularly harmful metals: cadmium, lead and mercury. According to one of the basic obligations, parties will have to reduce their emissions for these three metals below their levels in 1990. The Protocol aims to cut emissions from industrial sources, combustion process and waste incineration. It lays down strighten limit values for emissions from stationary sources and suggests best available techniques (BAT) for these sources, such as special filters or scrubbers for combustion sources or mercury-free processes. The Protocol requires parties to phase out leaded petrol. It also introduces measures to lower heavy metal emissions from other products, such as mercury in batteries, and proposes the introduciton of management measures for other mercury-containing products, such as electrical componets (thermostats, switches), measuring devices (thermometers, ...

2003-08-01

119

Pretreatment with U(IV) solution for improving the decontamination of ruthenium  

International Nuclear Information System (INIS)

The ruthenium decontamination factor in Purex process falls quickly in successive TBP cycles. So, it is necessary to change the chemical states of RuNO complexes in order to improve DF_R_u in the uranium purification cycle. Hydrazine nitrate is being used to transform RuNO complexes into in-extractable Ru(III)and Ru(IV). However, hydrazine nitrate may be inverted into hydrazoic acid which is dangerous and can bring an unstable factor. Pretreatment using U(IV) solution provides another method to improve the decontamination of ruthenium in Purex process. 0.02 mol/lU(IV) solution can transform RuNO complexes into inextricable species by heating in water bath. The D_R_u can be decreased by a factor of 10-20. U(IV) pretreatment does not bring any harmful chemical in process. The acidity has a very large influence on the effect of pretreatment. The higher the acidity is, the worse the effect will be.

120

Plastic wastes as support fuel. Jaetemuovin kaeyttoe tukipolttoaineena  

Energy Technology Data Exchange (ETDEWEB)

The association of Finnish Plastics Industry examined the possibilities to utilize energy content of plastic wastes in spring 1990. A bark fuelled boiler plant of forest industry was used as test power plant. The power of the plant was 60 Mw. This report discusses shortly the theory of combustion of plastics. About 130 000-15 000 tons of plastic waste, corresponding to 7 % of the solid municipal waste, is dumped annually in Finland. Utilization of the plastic waste recovered from municipal wastes for energy production is technically viable in present power plants among present energy production. The chipping and mixing of the plastic in the other fuel are the only pretreatment required for the plastic waste. In Finland there are several power plants using suitable fuels for plastic mixture combustion. The portion of the plastic of the total fuel power was 10 %. No problems occurred during the tests. The results of the tests are presented in this report. Special attention has been paid ...

1991-01-01

 
 
 
 
121

Organisms posses enzymes that function in the repair of DNA damaged by radiations, chemicals and metabolic events  

International Nuclear Information System (INIS)

This report briefly describes the studies on the mechanism of in vivo DNA repairing by the author in Research Reactor Institute, Kyoto Univ. for the past 30 years. First, the ability of UV radiation to induce transformation was investigated with viral DNA. The formation of thymine-thymine dimer was found harmful to organisms and such dimers were removable by UV-radiation at a low frequency. The mutability was determined in three different E.coli strains with mutator gene, mutT, mutS or mutL. The ability to excise 8-oxoguanin developed in primer DNA was deficient in mutT and miss-pairing left after DNA replication could not be recovered in mutL and mutS strains. Further, DNA repairing mechanism was investigated in other microorganisms; single-strand cleavage caused by exposure to BNCB radiation (boron-neutron-captured beam) could not be repaired in E. coli. Whereas for Deinococcus radiodurans, of which survival rate was not decreased by #gamma#-ray radiation at 5 ...

1998-01-01

122

On important matters (fire protection) related to No. 3 plant in the Hamaoka Nuclear Power Station, Chubu Electric Power Co., Inc., No. 2 plant in the Tsuruga Power Station, Japan Atomic Power Co., and No. 2 plant in the Sendai Nuclear Power Station, Kyushu Electric Power Co., Inc  

International Nuclear Information System (INIS)

The Nuclear Safety Commission acknowledged the policy of the Agency of Natural Resources and Energy to cope with these important matters on August 8, 1984. The main contents of the investigation and deliberation were as follows, As to the prevention of the occurrence of fires, the prevention of the leak and spread of inflammable liquid and gas, the installation of protective relays and so on, the use of incombustible materials and aseismatic design and the installation of lightning arresters. As to the detection of fires and fire fighting, the proper selection and arrangement of fire detectors and extinguishers, the extinguishers which do not harm the safety function of structures and equipment, and the extinguishers which are not affected by natural phenomena. As to the reduction of the effect of fires, the proper installation of fire walls and extinguishers, and the high temperature shut off of nuclear reactors which is never hampered by any fire. (Kako, I.).

1985-01-01

123

Influence of compound grease on the performance of premium connections  

Energy Technology Data Exchange (ETDEWEB)

The authors investigated the harmful effect of compound grease on premium connections. The pressure buildup of compound grease trapped between threads was measured during and after makeup of the connection. The resulting hoop stress in the coupling and the reduction in the seal interference were also measured. Mathematical models were developed to calculate coupling stress and grease pressure. Results indicate that for the conventional API buttress-thread profile, the pressure of trapped compound grease remains permanently high after the connection is made up because of the small thread-clearance area. This high pressure results in a high coupling stress and a large reduction in seal interference diameter, thereby degrading the integrity of the connection. To solve this problem, the thread profile was redesigned with a thread-clearance area larger than that of conventional buttress thread. The connection with the new thread design showed a significantly lower ...

1990-03-01

124

Industrial HVAC: a survey of design considerations  

Energy Technology Data Exchange (ETDEWEB)

Industrial facilities offer a wide variety of design challenges to engineers, including the mechanical engineers who design the HVAC, the process, exhaust, and other required mechanical systems; the mechanical contractors who install and maintain the systems (and who also may do design work); and the owners` engineers who are responsible for the day-to-day operation of their facilities. Along with the responsibility to see that all systems function as intended is the responsibility to ensure that all worker health concerns are addressed. These include heat stress avoidance and the proper control of harmful substances. The services of industrial hygienists may be required to ensure this. These may be independent consultants or the staff members of mechanical design firms. In addition, it is not unusual for major corporations that own manufacturing plants to have staff industrial hygienists. The accompanying sidebar presents a checklist of items to be considered when ...

1996-11-01

125

In vivo effects of cadmium chloride on certain aspects of protein metabolism in tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Heavy metals discharged from industries are a major source of pollution which has become a threat to all forms of life. Among the various heavy metals, cadmium is known to be highly toxic even in low concentrations. The harmful effects of cadmium is attributed to its effects on sulfhydryl groups of enzymes, especially dehydrogenases. Various aspects of cadmium pollution on fishes have been extensively reviewed. A survey of the literature reveals that few attempts have been made to study the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, has received little attention. The present study reports the influence of cadmium on certain aspects of protein metabolism in the tissues of a freshwater field crab, Barytelphusa guerini, and important component of the paddy field ecosystem, exposed to sublethal concentrations of ...

1991-04-01

126

Impact of oil and related chemicals on the marine environment  

International Nuclear Information System (INIS)

This review updates a previous review entitled ''Impact of Oil on the Marine Environment''. It covers oil and individual hydrocarbons, used lubricating oils, chemical control agents for oil spills, and wastes from offshore petroleum operations. It considers all major knowledge generated since the mid-1970s. The review covers its topics comprehensively, from a consideration of the composition, sources and inputs of oil to its ecological and human health effects and its effects on man's use of the sea. The review addresses several key questions on the present levels of contamination, the impact of hydrocarbons and related chemicals on marine biota, the recovery potential of marine ecosystems exposed to these contaminants, the degree of protection required for marine ecosystems known to be vulnerable and sensitive, and recommended research and other actions to fill gaps in knowledge. The review describes the hazards of marine oil pollution and associated chemicals and wastes as they are ...

127

Evaluation of the potential of pentachlorophenol degradation in soil by pulsed corona discharge plasma from soil characteristics.  

Science.gov (United States)

Chlorinated organics are frequently found as harmful soil contaminants and persisted for extended periods of time. A novel approach, named pulsed corona discharge plasma (PCDP), was employed for the degradation of pentachlorophenol (PCP) in soil. Experimental results showed that 87% of PCP could be smoothly removed in 60 min. Increasing pulse voltage, enhancing soil pH, lowering humic acid (HA) in soil and reducing granular size of the soil were found to be favorable for PCP degradation efficiency. Oxidation and physical processes simultaneously contributed to PCP removal in soil and ozone was the main factor in PCDP treatment. C-Cl bonds in PCP were cleaved during PCDP treatment by Fourier transform infrared spectroscopy (FTIR) analysis. The mineralization of PCP was confirmed by total organic carbon (TOC) and dechlorination analyses. The main intermediate products such as tetrachlorocatechol, tetrachlorohydroquinone, acetic acid, formic acid, and oxalic acid were ...

2010-04-15

128

Electromagnetic radiation unmasked  

International Nuclear Information System (INIS)

This article describes the nature of the electromagnetic waves, what they are and how do they affect us. Current concern is focused on exposure to low level power-frequency magnetic fields like microwave radiation from mobile phones and leaking microwave ovens; high power radiation from defence and airport radars; fields close to high voltage transmission lines; radio frequency fields from industrial welders and heaters and DC magnetic fields in aluminium smelters. These fields with frequency less than 300 GHz do not carry sufficient energy to break chemical bonds and it is assumed that they cannot damage cell DNA. The amount of radiation absorbed by a human exposed to far field electromagnetic radiation (EMR) depends on the orientation and size of the person. In the 30-300 MHz range it is possible to excite resonance in the whole or partial body such as the head. It is emphasised that since there are some evidence that electromagnetic fields do harm, a policy of ...

1996-01-01

129

Electricity generation: options for reduction in carbon emissions  

Energy Technology Data Exchange (ETDEWEB)

Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO{sub 2} each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO{sub 2} emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO{sub 2} emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion ...

2002-07-01

130

Effect of parameters on performance of LNG-FPSO offloading system in offshore associated gas fields  

Energy Technology Data Exchange (ETDEWEB)

Due to the advantages of the flexibility and economics in exploration and production of offshore liquefied natural gas (LNG), the floating production storage and offloading unit for liquefied natural gas (LNG-FPSO) has attracted wide attentions in recent years. The offloading system for LNG transportation from LNG-FPSO to LNG carrier is one of the most important parts in LNG-FPSO. The influences of the main parameters such as the mass flow rate and the height difference of the pipeline. on the performance of LNG offloading in offshore associated gas fields were investigated. A model based on a typical offshore LNG offloading system was first established and simulations were conducted. The governing equations were then used to evaluate the effects of parameters together with the simulation results. It was found that there was an economic mass flow rate for practical design on balance of the cost in pump head and BOG. The height difference of the pipeline must be considered for the ...

2010-11-15

131

Corrosion in drilling and well stimulation  

Energy Technology Data Exchange (ETDEWEB)

Corrosion in drilling and well stimulation is described in relation to acid corrosion inhibition, acid inhibitors, acetylenic inhibitors, synergistic blends, metallurgy, wellbore tubulars, coiled tubing, and high alloy tubular materials. Acidizing is a procedure for stimulating oil and gas wells. Factors that have an important influence on the reaction rate and the way in which acid reacts with rock include temperature, acid concentration, acid volume, injection velocity, acid viscosity, and fluid loss properties of the formation. The cost of drill pipe failures are $1 per fot of hole drilled, which is a significant fraction of the drilling cost. Steps in a test procedure are listed, as well as factors which determine the extent of acid corrosion in a given situation including acid type and strength, metal type, temperature, contact time; pressure, and volume/surface area ratio. Underbalanced drilling is a method for completing oil and gas wells that minimizes the ...

1999-07-01

132

Biological conversion of synthesis gas. Limiting conditions/scale-up  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this research is to develop a technically and economically feasible process for biologically producing H(sub 2) from synthesis gas while, at the same time, removing harmful sulfur gas compounds. Six major tasks are being studied: 1. Culture development, where the best cultures are selected and conditions optimized for simultaneous hydrogen production and sulfur gas removal; 2. Mass transfer and kinetic studies in which equations necessary for process design are developed; 3. Bioreactor design studies, where the cultures chosen in Task 1 are utilized in continuous reaction vessels to demonstrate process feasibility and define operating conditions; 4. Evaluation of biological synthetic gas conversion under limiting conditions in preparation for industrial demonstration studies; 5. Process scale-up where laboratory data are scaled to larger-size units in preparation for process demonstration in a pilot-scale unit; and 6. Economic evaluation, where ...

1993-09-01

133

Aspects of Stability Related to the Colliding Beam Fusion = Reactor  

Science.gov (United States)

Recent experiments with TFTR, D-III-D and JET involving the injection and trapping of low density beams of high energy large orbit ions indicate that large orbit non-adiabatic ions slow down and diffuse classically in the presence of anomalous fluctuations and transport of adiabatic majority particles. Accordingly, we consider conceptual fusion reactors(N. Rostoker, M.W. Binderbauer and H.J. Monkhorst, Science) 278, 1419 (1997). based on classical confinement of fuel ions and fusion products(M.W. Binderbauer and N. Rostoker, J. Plasma Phys.) 56, 451 (1996).. The magnetic confinement geometry of the proposed designs is a Field Reversed Configuration. A survey of experimental results on instabilities and their characteristics as related to these reactor concepts is presented. Particular focus will be given to long wavelength (as compared to gyro-radius) and low frequency (?<< c/r_o, r_o=3D major radius of annular current ring) instabilities as they are most ...

1998-11-01

134

An enhanced primary health care role following psychological trauma: the Christchurch earthquakes.  

Science.gov (United States)

Following the February 2011 earthquake in Christchurch, New Zealand (NZ), the authors participated in counselling local residents, and debriefing and supervising support teams. Indications were that risk for mental health disorders, including Post-Traumatic Stress Disorder (PTSD), may be elevated in residents, and that this risk may continue for some time. Patients may be de-prioritising their mental health issues when these become normalised throughout the city's population. The authors recommend that primary care patients are assessed using a brief, comprehensive tool (for example, the Case-finding and Help Assessment Tool) that targets many health and behavioural issues identified as increasing in the city following the earthquake. Anxiety and mood disorder symptoms may indicate assessment is appropriate to reduce harm arising from increased risk for PTSD. Concern also is raised for primary health care providers who may have experienced the trauma and ...

2011-09-01

135

Activated charcoal for water treatment which has expected demands in many fields  

Energy Technology Data Exchange (ETDEWEB)

The activated charcoal treatment in the field of the water treatment is applied to water supply, sewage, industrial water supply and industrial sewage, etc.. Its main treatment effects are (1) decolorization, (2) removal of odorous substance, (3) removal of organic material which is detected as COD or BOD, (4) removal of harmful substance, (5) removal of substance which could generate muddness and tarnish and (6) removal of organic material which affects the succeeding high degree treatment badly, etc.. Many actual application examples in the above fields have been reported. As the most recent topic, a big amount of the demand of activated charcoal is expected in the treatment of water supply. Chlorine which is used as disinfectant during the water purification process generates organic halogen compounds such as trihalomethane through the reaction with precursor such as humic acid. The countermeasure therefore is being developed in the direction of removing the ...

1988-10-01

136

A Robust and Efficient Trust Management Scheme for Peer-to-Peer Networks  

CERN Document Server

Studies on the large scale peer-to-peer (P2P) network like Gnutella have shown the presence of large number of free riders. Moreover, the open and decentralized nature of P2P network is exploited by malicious users who distribute unauthentic or harmful contents. Despite the existence of a number of trust management schemes in the literature for combating against free riding and distribution of malicious files, these mechanisms are not scalable due to their high computational, communication and storage overhead. These schemes also do not consider effect of trust management on quality-of-service (QoS) of the search. This paper presents a trust management scheme for P2P networks that minimizes distribution of spurious files by a novel technique called topology adaptation. It also reduces search time since most of the queries are resolved within the community of trustworthy peers. Simulation results indicate that the trust management overhead due to the pr oposed ...

2010-01-01

137

Geochemical and petrographic properties of some Spitsbergen coals and dispersed organic matter  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the characteristics of selected parameters of organic matter of the Tertiary coal samples and organic matter of Carboniferous rock samples from the Spitsbergen. The coal samples were taken from Central Coal Basin (the Longyearbyen region) and from the Forlandsundet Basin (Oscar II Land, the Kaffioyra region). Samples of dispersed organic matter were collected from Suffolk Pynten and Sergeijevfjellet area in Sorkapp Land. The optical properties of coal samples are different from properties of dispersed organic matter. Macerals of vitrinite group dominate in all of the samples. The average content of vitrinite group macerals is much lower in dipersed organic matter samples than it is in coals. The average content of liptinite group macerals is a little lower, and inertinite group macerals is much higher. The average content of mineral matter is higher in organic matter samples than in coal samples. The average value of vitrinite reflectance and standard deviation of ...

2004-02-20

138

Husky Oil's White Rose gets ready to bloom  

Energy Technology Data Exchange (ETDEWEB)

The South White Rose oilfield, offshore Newfoundland, owned jointly by Husky Oil (82.5 per cent ) and Petro-Canada (17.5 per cent) is being developed using a floating production storage and offloading (FPSO) system. Some industry stakeholders claim that the oil should be produced using a concrete gravity base system as used in the Hibernia Field. However, Husky Oil officials are confident that the choice of the FPSO is well justified, based on its cost effectiveness and economic viability. Several production facility options have been assessed, taking into account feasibility, deliverability, economic attributes. risk and safety . The assessment results clearly pointed to FPSO as the preferred system based on its commercial and technical flexibility, proven track record in harsh environments, its ability to produce both oil and gas in sequential development, its promise of production at full capacity earlier than a gravity base system, and easier decommissioning than a GBS-type fixed ...

2000-06-01

139

[Determination of sulfite in flue gas desulfurization with seawater by ion chromatography].  

Science.gov (United States)

The technology for flue gas desulfurization (FGD) with seawater is widely adopted by coal-fired power plants in coastal areas. SO2 in the flue gas is absorbed by alkaline seawater and transfered in aqueous phase as sulfite (SO3(2-)), and most SO3(2-) is transformed to sulfate (SO4(2-)) after an aeration process. The remaining SO3(2-) in the seawater discharged to sea area may be harmful to marine organism because of its biological toxicity, thus it is necessary to determine the concentration of SO3(2-) in the seawater for desulfurization. In this study, the method of determination of SO3(2-) in the seawater by ion chromatography was investigated. The separation was achieved on an IonPac AS14A column with 14 mmol/L NaOH-12 mmol/L Na2 CO3 solution as the mobile phase at a flow rate of 1.2 mL/min, and the detection was performed by a pulsed amperometric detector. Formaldehyde was added as a protective agent when sampling because the SO3(2-) is easy to be oxidized. To ...

2009-11-01

140

The Protective Effect of Antioxidants on Oxidative Stress in Rats Exposed to the 950 MHz Electromagnetic Field  

International Nuclear Information System (INIS)

Studies have linked cell phone radiation to health problems such as headaches, high blood pressure, cancer and more. There is a latency period for most diseases and it may take years and more studies before the required weight of evidence is established. But the effects are cumulative and precautions should be taken now before it is too late. The aim of the present study was to investigate if supplementation with antioxidants would protect heart and liver tissues from harmful radiation emitted by cell phone. Thirty two male albino rats were randomly divided into four equal groups: I- Control, II- Antioxidants treated group, III- 950 MHz EMR, IV- 950 MHz EMR + antioxidants. A 950 MHz EMR radiation (217-Hz pulse rate, 2-W maximum peak power, SAR Specific Absorption Rate"1.6 W/Kg) was applied to groups III and IV 60 min/day, for 30 days using an experimental exposure device. Antioxidants supplement (Vitamins A, E and C + Se) was administered to rats daily, by gavages, ...

 
 
 
 
141

Synfuels from coal: lessons from South Africa  

Energy Technology Data Exchange (ETDEWEB)

The strategy for building SASOL plants reflects a commitment to long-range planning. The first plant, which represented a large investment for a moderate production capacity, was built to establish a technology for reducing South Africa's dependence on imported motor fuels. After the success of the plant, SASOL made plans for a larger plant, which had to be justified solely on economic grounds. At that time, petroleum crude was cheap and plentiful, and the second plant was cancelled. But when OPEC formed and the price of petroleum crude was increased, the South African government reconsidered the plans for another SASOL plant. Furthermore, because the cost of fuels produced at Sasol I proved to be significantly insensitive to inflation and future OPEC price increases were expected, SASOL projected that a new, larger plant should make a profit within a few years after its initial operation. But OPEC prices and inflation have risen even faster than anticipated, and the products ...

1980-01-01

142

Synfuels from coal: lessons from South Africa  

Science.gov (United States)

The strategy for building SASOL plants reflects a commitment to long-range planning. The first plant, which represented a large investment for a moderate production capacity, was built to establish a technology for reducing South Africa's dependence on imported motor fuels. After the success of the plant, SASOL made plans for a larger plant, which had to be justified solely on economic grounds. At that time, petroleum crude was cheap and plentiful, and the second plant was cancelled. But when OPEC formed and the price of petroleum crude was increased, the South African government reconsidered the plans for another SASOL plant. Furthermore, because the cost of fuels produced at Sasol I proved to be significantly insensitive to inflation and future OPEC price increases were expected, SASOL projected that a new, larger plant should make a profit within a few years after its initial operation. But OPEC prices and inflation have risen even faster than anticipated, and the products ...

1980-01-01

143

Sodium monofluoroacetate (1080) risk assessment and risk communication  

International Nuclear Information System (INIS)

Sodium monofluoroacetate (1080) is a vertebrate pesticide widely used for possum control in New Zealand. Fluoroacetate is also a toxic component of poisonous plants found in Australia, South Africa, South America, and India. Because of its importance and effectiveness in pest control and the highly toxic nature of this compound, its acute sub-lethal and target organ toxicity have been extensively studied. In relation to its use as a pesticide its environmental fate, persistence, non-target impacts and general toxicology have been and continue to be extensively studied. Toxic baits must be prepared and used with extreme care, otherwise humans, livestock, and non-target wildlife will be put at risk. The high risk of secondary poisoning of dogs is a cause for concern. 1080 acts by interfering with cellular energy production. Possums die from heart failure, usually within 6-18 h of eating baits. Long-term exposure to sub-lethal doses can have harmful effects and strict ...

2002-12-27

144

Radiation 2006. In association with the Polymer Division, Royal Australian Chemical Institute. Incorporating the 21st AINSE Radiation Chemistry Conference and the 18th Radiation Biology Conference, conference handbook  

International Nuclear Information System (INIS)

Full text: The general population is daily exposed to chronic, low doses of ionizing radiation (IR) from both natural and artificial sources. The biological consequences of acute, high dose IR exposure can be readily determined; however, the nature and significance of low dose, low dose-rate IR effects are still the subject of debate. Confounding the issue, are the phenomena collectively referred to as the Radiation-induced Bystander Effect (RIBE). The RIBE describes a collection of in vitro observations that suggest the presence of a soluble, transmissible factor(s) released from irradiated cells that can induce a biological response in un-irradiated cells. The induction, nature and magnitude of the RIBE varies between cell culture systems, radiation sources and end-points measured. Efforts to confirm the presence of the RIBE in vivo have been confined to in vivo-like culture systems and limited work with tumour and bone-marrow transplantation models. Validation of the RIBE in vivo ...

2006-01-01

145

Purification of CH{sub 3}Cl from CH{sub 3}I using cold trap with sealed 2,2,4-trimethylpentane for {delta}{sup 37}Cl measurement  

Energy Technology Data Exchange (ETDEWEB)

A cryogenic separation method of chloromethane (CH{sub 3}Cl) from methyl iodide (CH{sub 3}I) for {delta}{sup 37}Cl measurement with isotope ratio mass spectrometer is described. A cold trap with sealed 2,2,4-trimethylpentane (TMP) as the cryogen is used in this method. CH{sub 3}Cl can be separated from CH{sub 3}I at the TMP melting point (-107 deg. C) based on the difference in the vapor pressure between CH{sub 3}Cl (322.6 Pa) and CH{sub 3}I (lower than 1.3 Pa) at -107 deg. C. After two-step separation processes, the yields of CH{sub 3}Cl purified from CH{sub 3}Cl-CH{sub 3}I mixture are 96-101%, and the difference between the {delta}{sup 37}Cl{sub original} and {delta}{sup 37}Cl{sub Afterseparation} is from -0.06 to +0.06 per mille (0.01 {+-} 0.04 per mille ). These results suggest that CH{sub 3}Cl is completely separated from CH{sub 3}I with no change of {delta}{sup 37}Cl value. This method using the cold trap with sealed TMP is very safe and not harmful, because ...

2006-01-05

146

Protection provided by criminal law against hazards of nuclear energy and the harmful effects of ionizing radiation. Also a survey of the history of definition of offences against the atomic energy law and radiation protection law in the Federal Republic of Germany. Der strafrechtliche Schutz vor den Gefahren der Kernenergie und den schaedlichen Wirkungen ionisierender Strahlen. Zugleich eine Darstellung der historischen Entwicklung der Kernenergie- und Strahlendelikte in der Bundesrepublik Deutschland  

Energy Technology Data Exchange (ETDEWEB)

The subjects, principles and purpose of the atomic energy law and the radiation protection law are set out, and criminal offences under atomic energy law are outlined explaining the legal terminology applied. The peaceful uses of nuclear energy and radioactive materials are briefly discussed, primarily looking at the hazards involved and the protective role of criminal law principles that have been developed in connection with the atomic energy law and its application in practice. The draft version of the 16th criminal law amendment act - Act to combat environmental delinquency - is discussed, which aims at adoption of all criminal offences under atomic energy law by the Criminal Code. The book furthermore presents considerations about basic features of delinquency under atomic energy and radiation protection law, revealing elements and facts of offences defined, and particular problems resulting thereof. The question arises, e.g., whether an incorporation of the provisions into the ...

1989-01-01

147

Outdoor chemistry of ozone precursors in the coastal atmosphere of Lebanon  

International Nuclear Information System (INIS)

Carbonyl compounds constitute an important reactive class of non methane volatile organic compounds. They can be emitted directly to the atmosphere from primary sources such as combustion engines, landfills and wastewater surfaces or as secondary products by the photochemical oxidation of hydrocarbons and other volatile organic compounds 1-3. Carbonyls photo-oxidize during the day to produce toxic radicals such as OH, HO_2, RO and RO_2. These species react with nitrogen oxides (NOx) and other VOCs present in the atmosphere to form tropospheric ozone (O_3); a highly reactive oxidizing agent that is harmful to human health, agricultural products and climate 4, 5. Hence identifying the levels and sources of ozone precursors such as low carbonyls, carbon monoxide (CO) and NOx derivatives, and understanding their physical and chemical transformation in the troposphere is an important task due to their atmospheric and adverse health implications. Diurnal variations of ...

148

Metallothionein (MT) response after chronic palladium exposure in the zebra mussel, Dreissena polymorpha  

International Nuclear Information System (INIS)

The effects of different exposure concentrations of palladium (Pd) on relative metallothionein (MT) response and bioaccumulation were investigated in zebra mussels (Dreissena polymorpha). The mussels were exposed to 0.05, 5, 50, and 500 ?g/L Pd2+ for 10 weeks under controlled temperature and fasting conditions. Relative MT contents were assessed by a modified Ag-saturation method, which allows to discriminate between MT bound to Pd (Pd-MT) and MT bound to unidentified metals (Ag-MT). Determination of metal contents resulted from atomic absorption spectrometry following a microwave digestion. For unexposed mussels and mussels exposed to 0.05 ?g/L Pd no metal accumulation could be detected. All other exposure concentrations resulted in detectable Pd accumulation in mussels with final tissue concentrations of 96 ?g/g (500 ?g/L), 45 ?g/g (50 ?g/L), and 9 ?g/g (5 ?g/L). Compared with initial levels Pd-MT concentrations at the end of the exposure period were 600 (500 ?g/L), 160 (50 ?g/L), ...

2008-11-01

149

Measurement of magnetic fields in the Area Metropolitana  

International Nuclear Information System (INIS)

The operation and proper handling of equipment for measuring EMR-300 electromagnetic waves are studied and apply that knowledge to determine which areas of the metropolitan area are mostly affected by exposure to the emission of radiation. This team is able to measure magnetic field strength, electric field strength and power density, also can measure the most important parameters in a simple manner. International standards provide maximum values for these parameters that limit human exposure to such radiation. These standards are based on epidemiological several and laboratory that have been carried out in order to determine in which circumstances a biological entity is exposed to a level of radiation that can cause harm to their health. It focuses on measuring the level of radiation in certain areas of interest, which were chosen because are areas with high population density and also in proximity to antennas that emit electromagnetic waves. Before carrying out ...

150

Influence of fuel additives on performance of direct-injection diesel engine and exhaust emissions when operating on shale oil  

Energy Technology Data Exchange (ETDEWEB)

The article presents the comparative bench testing results of a naturally aspirated four stroke, four cylinder, water cooled, direct injection Diesel engine when running on shale oil that has been treated with multi-functional fuel additives. The purpose of the research is to evaluate the effectiveness of the fuel additives Marisol FT (Sweden) and SO-2E (Estonia) as well as to verify their ability to increase energy conversion and reduce brake specific fuel consumption, contamination and smoke opacity of the exhausts when fuelling the Diesel engine with shale oil. Test results show that application of these additives could be a very efficient means to improve diesel engine performance on shale oil, especially when operating at the light load range. The brake specific fuel consumption at light loads and speeds of 1400-2000 min{sup -1} reduces by 18.3-11.0% due to the application of the Marisol FT. The additive SO-2E proves to produce nearly the same effect. The total NO{sub x} emission ...

2005-07-01

151

In vitro H2AX phosphorylation and micronuclei induction in human fibroblasts across the Bragg curve of a 577MeV/nucleon Fe incident beam  

Energy Technology Data Exchange (ETDEWEB)

The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the only major protection to astronauts from harmful exposure. Unlike low-linear energy transfer (LET) {gamma} or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure, since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak. The Bragg curve does not necessarily represent the biological damage along the particle traversal, and the 'biological Bragg curve' is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. Here we used a unique irradiation geometry to measure the biological response across the Bragg curve in human fibroblasts exposed to 577MeV/nucleon incident Fe ions in vitro. ...

2006-10-15

152

How to assess risk from combined exposures to radiation and other agents?  

Energy Technology Data Exchange (ETDEWEB)

Efforts to assess and quantify deleterious effects from toxicants concentrate mainly on single agents whereas real world environmental and occupational exposures to natural and anthropogenic agents entail quite often the concomitant presence of several toxicants. For occupational important exposure situations, combined exposures to physical and chemical agents such as radon and smoking or asbestos and smoking, respectively, were shown to produce over-additive effects at exposure levels typical for earlier workplaces. Already the elucidation of possible health risks from a single agents, its dependence on exposure level, exposure rates, age at exposure and its expression in time is a complex endeavour. Therefore in the past and the present the main emphasis in radiation protection, toxicology, and public health is on the study and assessment of single toxicants. The existing data base on combined effect is rudimentary, mainly descriptive and rarely covers exposure ranges large enough to ...

1997-03-01

153

Heterogeneous catalytic oxidative dehydrogenation of ethylbenzene to styrene with carbon dioxide  

Energy Technology Data Exchange (ETDEWEB)

Alkaline promoted active carbon supported iron catalysts are very active in the oxidative dehydrogenation of ethylbenzene to styrene in the presence of carbon dioxide. The best results were obtained at 550 C for a Li-promoted catalyst with a conversion of ethylbenzene of 75% and a selectivity towards styrene of nearly 95%. These results are better than those obtained with industrial catalysts which perform the dehydrogenation process with an excess of water. The main product of the dehydrogenation reaction with CO{sub 2} was styrene, but the following by-products were detected - benzene and toluene. The selectivity towards toluene was always higher than towards benzene. We observed also the formation of carbon monoxide and water, which were produced with a constant molar ratio of about 0.8. The weight of the catalysts increased up to 20% during the reaction due to deposition of carbon. Using a too large excess of CO{sub 2} (CO{sub 2}/EB>10) was harmful for the ...

1998-12-31

154

Gamma and X-ray shielding compositions utilizing bauxite - Red Mud regional research laboratory (CSIR), Bhopal, India  

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: The application spectrum of X-ray and Gamma radiation is increasing exponentially in the area of diagnostic, nuclear medicine, food preservation, nuclear power plants and strategic utilities. To prevent the harmful effects of these radiations, shielding materials based on lead metal and its compounds are being used historically, which are toxic in nature. To protect environment it has become necessary to develop non-toxic lead free shielding materials. The use of titanium metal and its compounds as synthetic rock i.e. SYNROC are reported to be very effective non-toxic shielding materials for various applications. Red mud waste generated in aluminum producing industries possesses a unique mineralogical compositions containing fairly high quantity of titanium oxide and iron oxide useful for making non toxic shielding compositions and therefore red mud has been utilized for the first time in the world ...

2007-09-02

155

Environmental benefits and economic rationale of expanding the Italian natural gas private car fleet  

International Nuclear Information System (INIS)

There are several concerns which bring to consider natural gas as a viable alternative to liquid fuels in transport. First, natural gas allows the curbing of global pollution in this steadily growing industry. Indeed, decoupling greenhouse gas emissions from transport growth has become a major issue in tackling climate change. Second, a more extensive use of natural gas would relieve city air quality, which is presently at levels harmful of human health. Nonetheless, this is just one side of the coin. The other side entails building a refuelling station network, and this carries financial requirements. The financing fraction holds a pivotal role in deciding whether natural gas for automotive purposes is an efficient solution. The final aim of this work is, therefore, to compare the natural gas advantages, stemming from avoided global and local emission, with the economic rationale of engaging in supplementary model network investments. A system dynamics model ...

2005-01-01

156

Effects of ions and electrons on atmospheric lifetimes of fully fluorinated compounds  

International Nuclear Information System (INIS)

Fully fluorinated compounds (perfluoro compounds) represent a class of chemicals which include many extremely inert species-inert to both chemical reaction and photodissociation. Well known examples include SF6 and the perfluorocarbons (PFCs) CF_4 and Teflon. SF_6 is used industrially in electrical switch gear and as an atmospheric tracer. CF_4 and C_2F_6 are released into the atmosphere as a by-product of aluminum manufacture. Several perfluoro compounds have been proposed as substitutes for the ozone-destroying Freons and halons; proposed substitutes include SF_6, c-C_4F_8, C_5F_1_2, and C_6F_1_4. These chemicals were chosen in part because they do not harm the stratospheric ozone layer and were therefore considered environmentally friendly. Recently, Ravishankara et al. reported that perfluoro compounds have significant global warming potential (GWP), contributing to the greenhouse effect due to strong infrared absorption. The perfluoro compounds have ...

1994-04-05

157

Effect of soil amendments and crop varieties on the amelioration of heavy metal uptake into crops grown on polluted soils of Bangladesh  

International Nuclear Information System (INIS)

Bangladesh possesses many industrial sites, whereby wastes and effluents are directly discharged into the environment without any treatment. Agricultural areas are contaminated thereby and the food quality is impaired. Therefore, the aim of the present work was to develop simple and cost effective strategies to reduce soil-plant transfer of harmful substances. Three sites were selected in the vicinity of Dhaka city (Tongi pharmaceutical, Tejgaon industrial and Hazaribagh tannery area). Field and pot experiments were carried out with different varieties of field crops (rice, wheat and tomato) and different soil amendments (cowdung, city waste compost, oil cake, waterhyacinth, poultry litter, lime and red mud). At the site Tongi, pollutants mainly consists of organic compounds. The soil of Tejgaon is acidic (pH=5.7), contains high organic matter and elevated concentrations of Zn (685 mg/kg), Pb (136 mg/kg), and Cd (2.6 mg/kg). The Hazaribagh region is polluted by a ...

158

Decision of the BVerwG (German Fed. Administrative Court) dated 10 Jan. 1995 - 7 B 112.94 -: Legal importance of the emission limits laid down in the TA Luft (Clean Air Technical Code); Beschluss des BVerwG vom 10.1.1995 - 7 B 112.94 -: Bedeutung der Emissionswerte der TA Luft  

Energy Technology Data Exchange (ETDEWEB)

Shortened excerpt from the head notes: The emission limits laid down in the TA Luft concretize the scope of the measures ordered by the law to provide for protection against harmful effects on the environment. Air pollution abatement measures imposed by the competent authority as post-licensing requirements based on the BImSchG (German Federal Emission Control Act) in general are in compliance with the principle of reasonableness considering the terms allowed by the TA Luft for backfitting measures. With this decision, the court qualified the emission limits defined in the TA Luft to be substantial and legally binding standards, to be applied by the competent authorities in licensing and post-licensing administrative procedures, also in order to fulfill the intended task of concretizing the less definite concepts of law laid down in the relevant legislation. (orig./CB) [Deutsch] Verkuerzte Zitierung aus den Leitsaetzen: Die in der TA Luft aufgestellten ...

1995-05-15

159

Bio-fuels for the gas turbine: A review  

International Nuclear Information System (INIS)

Due to depletion of fossil fuel, bio-fuels have generated a significant interest as an alternative fuel for the future. The use of bio-fuels to fuel gas turbine seems a viable solution for the problems of decreasing fossil-fuel reserves and environmental concerns. Bio-fuels are alternative fuels, made from renewable sources and having environmental benefit. In recent years, the desire for energy independence, foreseen depletion of nonrenewable fuel resources, fluctuating petroleum fuel costs, the necessity of stimulating agriculture based economy, and the reality of climate change have created an interest in the development of bio-fuels. The application of bio-fuels in automobiles and heating applications is increasing day by day. Therefore the use of these fuels in gas turbines would extend this application to aviation field. The impact of costly petroleum-based aviation fuel on the environment is harmful. So the development of alternative fuels in aviation is ...

2010-12-01

160

Ammonia recycling and destruction in a CFB gasifier  

Energy Technology Data Exchange (ETDEWEB)

Biomass contains nitrogen that is converted to NOx on combustion. Conversion of biomass into producer gas by thermal gasification offers an opportunity to reduce NOx-emissions by NH3 removal from the producer gas with water. Waste water will have to be treated before it can be drained. Recovered NH3 may have value as base chemical, but usually will have to be disposed off as waste. Recycling within the gasification process is an option to dispose off NH3 waste, provided NH3 is broken down under gasification conditions. We present experimental data on NH3 destruction in a CFB gasifier at temperatures from 780C to 860C, when NH3 is injected into the gasification air. Within that temperature range, the fraction of NH3 that is broken down increases from less than 50% to nearly 100%. Clearly, the presence of O2 at the injection point leads to a much higher rate of NH3 destruction than observed for purely thermal cracking. Although measurement of the NOx concentration in producer gas is ...

2004-05-01

 
 
 
 
161

Aflatoxin-producing Aspergillus spp. and aflatoxin levels in stored cassava chips as affected by processing practices  

DEFF Research Database (Denmark)

Cassava chips (cassava balls, and cassava pellets) are derived cassava products traditionally produced by farmers in sub-Saharan Africa following fermentation, and drying of fresh roots of cassava, and are widely consumed in Cameroon. Once produced, this food commodity can be stored for more than two months and contaminated by a wide array of harmful microbes. In order to assess persistence of toxigenic fungi in cassava chips, aflatoxin-producing fungi (Aspergillus flavus, Aspergillus nomius, and Aspergillus parasiticus) and aflatoxins were contrasted at regular intervals in home-stored cassava chips collected in two locations of southern Cameroon throughout a two-month monitoring period. Three hundred and forty-six isolates of aflatoxin-producing fungi were found to be associated with all samples. A. flavus contaminated more samples in both types of chips (267 isolates in 53 samples), followed by A. nomius (58 isolates in 15 samples), whereas A. parasiticus was ...

2009-01-01

162

MAJOR OIL PLAYS IN UTAH AND VICINITY  

Energy Technology Data Exchange (ETDEWEB)

Utah oil fields have produced over 1.2 billion barrels (191 million m{sup 3}). However, the 13.7 million barrels (2.2 million m{sup 3}) of production in 2002 was the lowest level in over 40 years and continued the steady decline that began in the mid-1980s. The Utah Geological Survey believes this trend can be reversed by providing play portfolios for the major oil-producing provinces (Paradox Basin, Uinta Basin, and thrust belt) in Utah and adjacent areas in Colorado and Wyoming. Oil plays are geographic areas with petroleum potential caused by favorable combinations of source rock, migration paths, reservoir rock characteristics, and other factors. The play portfolios will include: descriptions and maps of the major oil plays by reservoir; production and reservoir data; case-study field evaluations; summaries of the state-of-the-art drilling, completion, and secondary/tertiary techniques for each play; locations of major oil pipelines; descriptions of reservoir outcrop analogs; and ...

2003-09-01

163

Simulation of sludge deposit onto a 900 MW steam generator tubesheet with the 3D code GENEPI  

Energy Technology Data Exchange (ETDEWEB)

Heat transfer processes use fluids which are generally not pure and can react with transfer surfaces. These surfaces are subject to deposits which can be sediments harmful to heat transfer and to integrity of materials. For nuclear plant steam generators, sludge build-up accelerates secondary side corrosion by concentrating chemical species. A major safety problem involved with such a corrosion is the growing of circumferential cracks which are very difficult to detect and size with eddy current probes. With a view to understand and control this problem, it is necessary to develop a mathematical model for the prediction of sludge behavior in PWR steam generators. Based on fundamental principles, this work intends to use different models available in literature for the prediction of the phenomenon leading to the accumulation of sludge particles at the bottom (the tubesheet) of a PWR. For that, a three-dimensional simulation of magnetite particulate fouling with the ...

1998-07-01

164

Scour protection for wind turbine foundations on highly erodible sea bottom  

Energy Technology Data Exchange (ETDEWEB)

Scour around offshore structures is well known. It is caused by the strong eddy formation at the base of the structures protruding from the sea bottom. The strong vortices result in an amplified effective shear stress working on the sea bottom surface adjacent to the structure. When the surrounding sea bottom is lowered the scour protection will end up being a cap on a small hill and when the slopes are getting too steep the scour protection will roll or slide down the sides. It will loose its cohesion and therefore its integrity. This will take place irrespective of the type of scour protection material and the type of scour protection. This report describes scour protections, which can deal with this particular problem. Such a scour protection must be able to sustain the following loads: Be able to follow the lowering of the seabed on its way down; Be resistant to edge scour (scour around the perimeter of the scour protection). The installation of scour protection is not ...

2002-12-01

165

Recent environment, energy and resources cases and issues in Alberta  

Energy Technology Data Exchange (ETDEWEB)

Significant environmental issues and regulatory proceedings in Alberta were discussed. The Mackenzie Valley Pipeline Project was reviewed in relation to the Deh Cho First Nation's advanced actions in the federal court to enjoin the review panel from proceeding with the review process. The Deh Cho First Nation is seeking a declaration that the plan violates their rights under the Canadian Charter of Rights and Freedoms and the Constitution Act. Various regulatory and government agencies have now developed a plan to coordinate their different regulatory processes and approvals in the Cooperation Plan for the Environmental Impact Assessment and Regulatory Review of the Northern Gas Pipeline project. The Deh Cho allege that they were not afforded the opportunity to participate in the development and implementation of the plan. A review panel plans to proceed once the environmental and social impacts are determined, and the consortiums plan to minimize harm has ...

2005-07-01

166

Application of low-dose radiation protocols in survey CT scans  

International Nuclear Information System (INIS)

Objective: To characterize the protocols with low-dose radiation in survey CT scans for localization. Methods: Eighty standard adult patients, head and body phantoms were recruited. Default protocols provided by operator's manual setting were that all the tube voltage for head, chest, abdomen and lumbar was 120 kV; the tube currents were 20,10,20 and 40 mA, respectively. Values of kV and mA in the low-dose experiments were optimized according to the device options. For chest and abdomen, the tube position were compared between default (0 degree) and 180 degree. Phantoms were scanned with above protocols, and the radiation doses were measured respectively. Paired t-test were used for comparisons of standard deviation in CT value, noise and exposure surface dose (ESD) between group with default protocols and group with optimized protocols. Results: The optimized protocols in low-dose CT survey scans were 80 kV, 10 mA for head, 80 kV, 10 mA for chest, 80 kV, 10 mA for abdomen and 100 kV, ...

2009-08-01