Note: This page contains sample records for the topic particulate ecto-nucleotidase cd39 from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
1

Rat pancreas secretes particulate ecto-nucleotidase CD39  

PubMed Central

In exocrine pancreas, acini release ATP and the excurrent ducts express several types of purinergic P2 receptors. Thereby, ATP, or its hydrolytic products, might play a role as a paracrine regulator between acini and ducts. The aim of the present study was to elucidate whether this acinar-ductal signalling is regulated by nucleotidase(s), and to characterize and localize one of the nucleotidases within the rat pancreas. Using RT-PCR and Western blotting we show that pancreas expresses the full length ecto-nucleoside triphosphate diphosphohydrolase, CD39. Immunofluorescence shows CD39 localization on basolateral membranes of acini and intracellularly. In small intercalated/ interlobular ducts, CD39 immunofluorescence was localized on the luminal membranes, while in larger ducts it was localized on the basolateral membranes. Upon stimulation with cholecystokinin-octapeptide-8 (CCK-8), acinar CD39 relocalizes in clusters towards the lumen and is secreted. As a result, pancreatic juice collected from intact pancreas stimulated with CCK-8 contained nucleotidase activity, including that of CD39, and no detectable amounts of ATP. Anti-CD39 antibodies detected the full length (78 kDa) CD39 in pancreatic juice. This CD39 was confined only to the particulate and not to the soluble fraction of CCK-8-stimulated secretion. No CD39 activity was detected in secretion stimulated by secretin. The role of secreted particulate, possibly microsomal, CD39 would be to regulate intraluminal ATP concentrations within the ductal tree. In conclusion, we show a novel inducible release of full length particulate CD39, and propose its role in the physiological context of pancreatic secretion.

S?rensen, Christiane E; Amstrup, Jan; Rasmussen, Hans N; Ankorina-Stark, Ieva; Novak, Ivana

2003-01-01

2

Ecto-nucleotidases distribution in human cyclic and postmenopausic endometrium.  

PubMed

Extracellular ATP and its hydrolysis product, adenosine, acting through specific receptors collectively named purinergic receptors, regulate female fertility by influencing the endometrial fluid microenvironment. There are four major groups of ecto-nucleotidases that control the levels of extracellular ATP and adenosine and thus their availability at purinergic receptors: ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases), ecto-nucleotide pyrophosphatase/phospho-diesterases (E-NPPs), ecto-5'-nucleotidase (5'NT), and alkaline phosphatases (APs). The aim of the present work is to characterize the expression and distribution of ecto-nucleotidases in human endometrium along the menstrual cycle and after menopause, to evaluate their potential utility as fertility markers. We examined proliferative, secretory and atrophic endometria from women without endometrial pathology undergoing hysterectomy. We show that the ecto-nucleotidases are mainly present at endometrial epithelia, both luminal and glandular, and that their expression fluctuates along the cycle and also changes after menopause. An important result was identifying NPP3 as a new biological marker of tubal metaplasia. Our results emphasize the relevance of the study of purinergic signaling in human fertility. PMID:23225236

Aliagas, Elisabet; Vidal, August; Torrejón-Escribano, Benjamín; Taco, Maria del Rosario; Ponce, Jordi; de Aranda, Inmaculada Gómez; Sévigny, Jean; Condom, Enric; Martín-Satué, Mireia

2013-06-01

3

CD39 activity correlates with stage and inhibits platelet reactivity in chronic lymphocytic leukemia  

Microsoft Academic Search

BACKGROUND: Chronic lymphocytic leukemia (CLL) is characterized by accumulation of mature appearing lymphocytes and is rarely complicated by thrombosis. One possible explanation for the paucity of thrombotic events in these patients may be the presence of the ecto-nucleotidase CD39\\/NTDPase-1 on the surface of the malignant cells in CLL. CD39 is the major promoter of platelet inhibition in vivo via its

Dianne Pulte; Kim E Olson; M Johan Broekman; Naziba Islam; Harold S Ballard; Richard R Furman; Ashley E Olson; Aaron J Marcus

2007-01-01

4

Ecto-Nucleotidase Activities of Promastigotes from Leishmania (Viannia) braziliensis Relates to Parasite Infectivity and Disease Clinical Outcome  

PubMed Central

Background Leishmania (Viannia) braziliensis has been associated with a broad range of clinical manifestations ranging from a simple cutaneous ulcer to destructive mucosal lesions. Factors leading to this diversity of clinical presentations are not clear, but parasite factors have lately been recognized as important in determining disease progression. Given the fact that the activity of ecto-nucleotidases correlates with parasitism and the development of infection, we evaluated the activity of these enzymes in promastigotes from 23 L. braziliensis isolates as a possible parasite-related factor that could influence the clinical outcome of the disease. Methodology/Principal Findings Our results show that the isolates differ in their ability to hydrolyze adenine nucleotides. Furthermore, we observed a positive correlation between the time for peak of lesion development in C57BL/6J mice and enzymatic activity and clinical manifestation of the isolate. In addition, we found that L. (V.) braziliensis isolates obtained from mucosal lesions hydrolyze higher amounts of adenine nucleotides than isolates obtained from skin lesions. One isolate with high (PPS6m) and another with low (SSF) ecto-nucleotidase activity were chosen for further studies. Mice inoculated with PPS6m show delayed lesion development and present larger parasite loads than animals inoculated with the SSF isolate. In addition, PPS6m modulates the host immune response by inhibiting dendritic cell activation and NO production by activated J774 macrophages. Finally, we observed that the amastigote forms from PPS6m and SSF isolates present low enzymatic activity that does not interfere with NO production and parasite survival in macrophages. Conclusions/Significance Our data suggest that ecto-nucleotidases present on the promastigote forms of the parasite may interfere with the establishment of the immune response with consequent impaired ability to control parasite dissemination and this may be an important factor in determining the clinical outcome of leishmaniasis.

Leite, Pauline M.; Gomes, Rodrigo S.; Figueiredo, Amanda B.; Serafim, Tiago D.; Tafuri, Wagner L.; de Souza, Carolina C.; Moura, Sandra A. L.; Fietto, Juliana L. R.; Melo, Maria N.; Ribeiro-Dias, Fatima; Oliveira, Milton A. P.; Rabello, Ana; Afonso, Luis C. C.

2012-01-01

5

Stem cell characteristics in glioblastoma are maintained by the ecto-nucleotidase E-NPP1.  

PubMed

Glioblastomas are highly aggressive brain tumours and are characterised by substantial cellular heterogeneity within a single tumour. A sub-population of glioblastoma stem-like cells (GSCs) that shares properties with neural precursor cells has been described, exhibiting resistance to therapy and therefore being considered responsible for the high recurrence rate in glioblastoma. To elucidate the underlying cellular processes we investigated the role of phosphatases in the GSC phenotype, using an in vitro phosphatome-wide RNA interference screen. We identified a set of genes, the knockdown of which induces a significant decrease in the glioma stem cell marker CD133, indicating a role in the glioblastoma stem-like phenotype. Among these genes, the ecto-nucleotidase ENPP1 (ectonucleotide pyrophosphatase/phosphodiesterase 1) was found to be highly expressed in GSCs compared with normal brain and neural stem cells. Knockdown of ENPP1 in cultured GSCs resulted in an overall downregulation of stem cell-associated genes, induction of differentiation into astrocytic cell lineage, impairment of sphere formation, in addition to increased cell death, accumulation of cells in G1/G0 cell cycle phase and sensitisation to chemotherapeutic treatment. Genome-wide gene expression analysis and nucleoside and nucleotide profiling revealed that knockdown of ENPP1 affects purine and pyrimidine metabolism, suggesting a link between ENPP1 expression and a balanced nucleoside-nucleotide pool in GSCs. The phenotypic changes in E-NPP1-deficient GSCs are assumed to be a consequence of decreased transcriptional function of E2F1. Together, these results reveal that E-NPP1, by acting upstream of E2F1, is indispensable for the maintenance of GSCs in vitro and hence required to keep GSCs in an undifferentiated, proliferative state. PMID:24531536

Bageritz, J; Puccio, L; Piro, R M; Hovestadt, V; Phillips, E; Pankert, T; Lohr, J; Herold-Mende, C; Lichter, P; Goidts, V

2014-06-01

6

Human monocyte derived dendritic cells express functional P2X and P2Y receptors as well as ecto-nucleotidases  

Microsoft Academic Search

We investigated the expression and function of P2 receptors and ecto-nucleotidases on human monocyte derived dendritic cells (DC). In addition we analyzed the effect of extracellular ATP on the maturation of DC. By RT-PCR, DC were found to express mRNA for several P2X (P2X1, P2X4, P2X5, P2X7) and P2Y (P2Y1, P2Y2, P2Y4, P2Y5, P2Y6, P2Y10, P2Y11) receptors. As shown by

Susanne Berchtold; Alexandra L. J. Ogilvie; Cornelia Bogdan; Petra Mühl-Zürbes; Adaling Ogilvie; Gerold Schuler; Alexander Steinkasserer

1999-01-01

7

CD39: Interface between vascular thrombosis and inflammation.  

PubMed

Extracellular nucleotides play a critical role in vascular thrombosis and inflammation. Alterations in purinergic extracellular nucleotide concentrations activate pathways that result in platelet degranulation and aggregation, and endothelial and leukocyte activation and recruitment. CD39, the dominant vascular nucleotidase, hydrolyzes ATP and ADP to provide the substrate for generation of the anti-inflammatory and antithrombotic mediator adenosine. The purinergic signaling system, with CD39 at its center, plays an important role in modulating vascular homeostasis and the response to vascular injury, as seen in clinically relevant diseases such as stroke, ischemia-reperfusion injury, and pulmonary hypertension. A growing body of knowledge of the purinergic signaling pathway implicates CD39 as a critical modulator of vascular thrombosis and inflammation. Therapeutic strategies targeting CD39 offer promising opportunities in the management of vascular thromboinflammatory diseases. PMID:24838375

Kanthi, Yogendra M; Sutton, Nadia R; Pinsky, David J

2014-07-01

8

Variable Impact of CD39 in Experimental Murine Colitis  

Microsoft Academic Search

Background  Dysregulation of immune responses in inflammatory bowel diseases (IBD) results in intestinal inflammation and vascular injury\\u000a while exacerbating systemic disease. CD39 is an ectonucleotidase, expressed by T regulatory cells and dendritic cells, that\\u000a hydrolyzes extracellular nucleotides to modify those cellular immune responses implicated in IBD. Genetic polymorphisms of\\u000a CD39 have been linked to Crohn’s disease while gene deletion in mice

Beat M. Künzli; Pascal O. Berberat; Karen Dwyer; Silvia Deaglio; Eva Csizmadia; Peter Cowan; Anthony d’Apice; Gregory Moore; Keiichi Enjyoji; Helmut Friess; Simon C. Robson

2011-01-01

9

CD39/Adenosine Pathway Is Involved in AIDS Progression  

PubMed Central

HIV-1 infection is characterized by a chronic activation of the immune system and suppressed function of T lymphocytes. Regulatory CD4+ CD25high FoxP3+CD127low T cells (Treg) play a key role in both conditions. Here, we show that HIV-1 positive patients have a significant increase of Treg-associated expression of CD39/ENTPD1, an ectoenzyme which in concert with CD73 generates adenosine. We show in vitro that the CD39/adenosine axis is involved in Treg suppression in HIV infection. Treg inhibitory effects are relieved by CD39 down modulation and are reproduced by an adenosine-agonist in accordance with a higher expression of the adenosine A2A receptor on patients' T cells. Notably, the expansion of the Treg CD39+ correlates with the level of immune activation and lower CD4+ counts in HIV-1 infected patients. Finally, in a genetic association study performed in three different cohorts, we identified a CD39 gene polymorphism that was associated with down-modulated CD39 expression and a slower progression to AIDS.

Limou, Sophie; Younas, Mehwish; Kok, Ayrin; Hue, Sophie; Seddiki, Nabila; Hulin, Anne; Delaneau, Olivier; Schuitemaker, Hanneke; Herbeck, Joshua T.; Mullins, James I.; Muhtarova, Maria; Bensussan, Armand; Zagury, Jean-Francois; Lelievre, Jean-Daniel; Levy, Yves

2011-01-01

10

CD39 and CD73 in immunity and inflammation  

PubMed Central

The enzymatic activities of CD39 and CD73 play strategic roles in calibrating the duration, magnitude, and chemical nature of purinergic signals delivered to immune cells through the conversion of ADP/ATP to AMP and AMP to adenosine, respectively. This drives a shift from an ATP-driven proinflammatory environment to an anti-inflammatory milieu induced by adenosine. The CD39/CD73 pathway changes dynamically with the pathophysiological context in which it is embedded. It is becoming increasingly appreciated that altering this catabolic machinery can change the course or dictate the outcome of several pathophysiological events, such as AIDS, autoimmune diseases, infections, atherosclerosis, ischemia-reperfusion injury, and cancer, suggesting these ecto-enzymes are novel therapeutic targets for managing a variety of disorders.

Antonioli, Luca; Pacher, Pal; Vizi, E. Sylvester; Hasko, Gyorgy

2013-01-01

11

Heightened NTPDase-1\\/CD39 expression and angiogenesis in radiation proctitis  

Microsoft Academic Search

Radiation proctitis is an inflammatory process associated with persistent and refractory lower gastrointestinal bleeding.\\u000a Purinergic signaling regulates hemostasis, inflammation, and angiogenesis. For example, CD39, the vascular ectonucleotidase,\\u000a blocks platelet activation and is required for angiogenesis. Whether CD39 expression is affected by radiation injury is unknown.\\u000a The aim of this work was to study CD39 expression patterns after clinical radiation injury

Sunil Sheth; Wissam Bleibel; Chandrashekhar Thukral; Yousif A-Rahim; Guido Beldi; Eva Csizmadia; Simon C. Robson

2009-01-01

12

Impact of CD39 and purinergic signalling on the growth and metastasis of colorectal cancer.  

PubMed

Despite improvements in prevention and management of colorectal cancer (CRC), uncontrolled tumor growth with metastatic spread to distant organs remains an important clinical concern. Genetic deletion of CD39, the dominant vascular and immune cell ectonucleotidase, has been shown to delay tumor growth and blunt angiogenesis in mouse models of melanoma, lung and colonic malignancy. Here, we tested the influence of CD39 on CRC tumor progression and metastasis by investigating orthotopic transplanted and metastatic cancer models in wild-type BALB/c, human CD39 transgenic and CD39 deficient mice. We also investigated CD39 and P2 receptor expression patterns in human CRC biopsies. Murine CD39 was expressed by endothelium, stromal and mononuclear cells infiltrating the experimental MC-26 tumors. In the primary CRC model, volumes of tumors in the subserosa of the colon and/or rectum did not differ amongst the treatment groups at day 10, albeit these tumors rarely metastasized to the liver. In the dissemination model, MC-26 cell line-derived hepatic metastases grew significantly faster in CD39 over-expressing transgenics, when compared to CD39 deficient mice. Murine P2Y2 was significantly elevated at both mRNA and protein levels, within the larger liver metastases obtained from CD39 transgenic mice where changes in P2X7 levels were also noted. In clinical samples, lower levels of CD39 mRNA in malignant CRC tissues appeared associated with longer duration of survival and could be linked to less invasive tumors. The modulatory effects of CD39 on tumor dissemination and differential levels of CD39, P2Y2 and P2X7 expression in tumors suggest involvement of purinergic signalling in these processes. Our studies also suggest potential roles for purinergic-based therapies in clinical CRC. PMID:21484085

Künzli, Beat M; Bernlochner, Maria-Isabell; Rath, Stephan; Käser, Samuel; Csizmadia, Eva; Enjyoji, Keiichi; Cowan, Peter; d'Apice, Anthony; Dwyer, Karen; Rosenberg, Robert; Perren, Aurel; Friess, Helmut; Maurer, Christoph A; Robson, Simon C

2011-06-01

13

CD39 is incorporated into plasma microparticles where it maintains functional properties and impacts endothelial activation  

PubMed Central

Summary Plasma microparticles (MPs, <1.5 ?m) originate from platelet and cell membrane lipid rafts and possibly regulate inflammatory responses and thrombogenesis. These actions are mediated through their phospholipid-rich surfaces and associated cell-derived surface molecules. The ectonucleotidase CD39/ecto-nucleoside triphosphate diphosphohydrolase1 (E-NTPDase1) modulates purinergic signalling through pericellular ATP and ADP phosphohydrolysis and is localized within lipid rafts in the membranes of endothelial- and immune cells. This study aimed to determine whether CD39 associates with circulating MPs and might further impact phenotype and function. Plasma MPs were found to express CD39 and exhibited classic E-NTPDase ecto-enzymatic activity. Entpd1 (Cd39) deletion in mice produced a pro-inflammatory phenotype associated with quantitative and qualitative differences in the MP populations, as determined by two dimensional-gel electrophoresis, western blot and flow cytometry. Entpd1-null MPs were also more abundant, had significantly higher proportions of platelet- and endothelial-derived elements and decreased levels of interleukin-10, tumour necrosis factor receptor 1 and matrix metalloproteinase 2. Consequently, Cd39-null MP augment endothelial activation, as determined by inflammatory cytokine release and upregulation of adhesion molecules in vitro. In conclusion, CD39 associates with circulating MP and may directly or indirectly confer functional properties. Our data also suggest a modulatory role for CD39 within MP in the exchange of regulatory signals between leucocytes and vascular cells.

Banz, Yara; Beldi, Guido; Wu, Yan; Atkinson, Ben; Usheva, Anny; Robson, Simon C.

2010-01-01

14

Vascular CD39/ENTPD1 directly promotes tumor cell growth by scavenging extracellular adenosine triphosphate.  

PubMed

Extracellular adenosine triphosphate (ATP) is known to boost immune responses in the tumor microenvironment but might also contribute directly to cancer cell death. CD39/ENTPD1 is the dominant ectonucleotidase expressed by endothelial cells and regulatory T cells and catalyzes the sequential hydrolysis of ATP to AMP that is further degraded to adenosine by CD73/ecto-5'-nucleotidase. We have previously shown that deletion of Cd39 results in decreased growth of transplanted tumors in mice, as a result of both defective angiogenesis and heightened innate immune responses (secondary to loss of adenosinergic immune suppression). Whether alterations in local extracellular ATP and adenosine levels as a result of CD39 bioactivity directly affect tumor growth and cytotoxicity has not been investigated to date. We show here that extracellular ATP exerts antitumor activity by directly inhibiting cell proliferation and promoting cancer cell death. ATP-induced antiproliferative effects and cell death are, in large part, mediated through P2X(7) receptor signaling. Tumors in Cd39 null mice exhibit increased necrosis in association with P2X(7) expression. We further demonstrate that exogenous soluble NTPDase, or CD39 expression by cocultured liver sinusoidal endothelial cells, stimulates tumor cell proliferation and limits cell death triggered by extracellular ATP. Collectively, our findings indicate that local expression of CD39 directly promotes tumor cell growth by scavenging extracellular ATP. Pharmacological or targeted inhibition of CD39 enzymatic activity may find utility as an adjunct therapy in cancer management. PMID:21390184

Feng, Lili; Sun, Xiaofeng; Csizmadia, Eva; Han, Lihui; Bian, Shu; Murakami, Takashi; Wang, Xin; Robson, Simon C; Wu, Yan

2011-03-01

15

Human SolCD39 Inhibits Injury-induced Development of Neointimal Hyperplasia  

PubMed Central

SUMMARY Blood platelets provide the initial response to vascular endothelial injury, becoming activated as they adhere to the injured site. Activated platelets recruit leukocytes, and initiate proliferation and migration of vascular smooth muscle cells (SMC) within the injured vessel wall, leading to development of neointimal hyperplasia. Endothelial CD39/NTPDase1 and recombinant solCD39 rapidly metabolize nucleotides, including stimulatory ADP released from activated platelets, thereby suppressing additional platelet reactivity. Using a murine model of vascular endothelial injury, we investigated whether circulating human solCD39 could reduce platelet activation and accumulation, thus abating leukocyte infiltration and neointimal formation following vascular damage. Intraperitoneally-administered solCD39 ADPase activity in plasma peaked 1 hr post-injection, with an elimination half-life of 43 hr. Accordingly, mice were administered solCD39 or saline 1 hr prior to vessel injury, then either sacrificed 24 hr post-injury or treated with solCD39 or saline (3X weekly) for an additional 18 days. 24 hr post-injury, solCD39-treated mice displayed a reduction in platelet activation and recruitment, P-selectin expression, and leukocyte accumulation in the arterial lumen. Furthermore, repeated administration of solCD39 modulated the late stage of vascular injury by suppressing leukocyte deposition, macrophage infiltration and SMC proliferation/migration, resulting in abrogation of neointimal thickening. In contrast, injured femoral arteries of saline-injected mice exhibited massive platelet thrombus formation, marked P-selectin expression, and leukocyte infiltration. Pronounced neointimal growth with macrophage and SMC accretion was also observed (intimal-to-medial area ratio 1.56±0.34 at 19 days). Thus, systemic administration of solCD39 profoundly affects injury-induced cellular responses, minimizing platelet deposition and leukocyte recruitment, and suppressing neointimal hyperplasia.

Drosopoulos, Joan H. F.; Kraemer, Rosemary; Shen, Hao; Upmacis, Rita K.; Marcus, Aaron J.; Musi, Elgilda

2010-01-01

16

Regulation of ecto-apyrase CD39 (ENTPD1) expression by phosphodiesterase III (PDE3).  

PubMed

The ectoenzyme CD39 suppresses thrombosis and inflammation by suppressing ATP and ADP to AMP. However, mechanisms of CD39 transcriptional and post-translational regulation are not well known. Here we show that CD39 levels are modulated by inhibition of phosphodiesterase 3 (PDE3). RAW macrophages and human umbilical vein endothelial cells (HUVECs) were treated with the PDE3 inhibitors cilostazol and milrinone, then analyzed using qRT-PCR, immunoprecipitation/Western blot, immunofluorescent staining, radio-thin-layer chromatography, a malachite green assay, and ELISA. HUVECs expressed elevated CD39 protein (2-fold [P<0.05] for cilostazol and 2.5-fold [P<0.01] for milrinone), while macrophage CD39 mRNA and protein were both elevated after PDE3 inhibition. HUVEC ATPase activity increased by 25% with cilostazol and milrinone treatment (P<0.05 and P<0.01, respectively), as did ADPase activity (47% and 61%, P<0.001). There was also a dose-dependent elevation of soluble CD39 after treatment with 8-Br-cAMP, with maximal elevation of 60% more CD39 present compared to controls (1 mM, P<0.001). Protein harvested after 8-Br-cAMP treatment showed that ubiquitination of CD39 was decreased by 43% compared to controls. A DMSO or PBS vehicle control was included for each experiment based on solubility of cilostazol, milrinone, and 8-Br-cAMP. These results indicate that PDE3 inhibition regulates endothelial CD39 at a post-translational level. PMID:23901069

Baek, Amy E; Kanthi, Yogendra; Sutton, Nadia R; Liao, Hui; Pinsky, David J

2013-11-01

17

Increased plasma levels of microparticles expressing CD39 and CD133 in acute liver injury  

PubMed Central

Background We have previously demonstrated that CD133 and CD39 are expressed by hematopoietic stem cells (HSC), which are mobilized after liver injury and target sites of injury, limit vascular inflammation and boost hepatic regeneration. Plasma microparticles (MP) expressing CD39 can block endothelial activation. Here, we tested whether CD133+ MP might be shed in a CD39-dependent manner in a model of liver injury and could potentially serve as biomarkers of liver failure in the clinic. Methods Wild type and Cd39 null mice were subjected to acetaminophen (APAP)-induced liver injury. Mice were sacrificed and plasma MP isolated by ultracentrifugation. HSC and CD133+ MP levels were analyzed by FACS. Patients were enrolled with acute (n = 5) and acute on chronic (n = 5) liver injury with matched controls (n = 7). Blood was collected at admission and plasma CD133+ and CD39+ MP subsets were analysed by FACS. Results HSC and CD133+ MP levels were significantly increased only in the plasma of wild type mice with APAP-hepatoxicity (p<0.05). No increases in CD133+ MP were noted in Cd39 null mice. Plasma MP increases were observed in patients with liver injury. These MP were characterized by significantly higher levels of CD39 (P< 0.05). Conclusions HSC and plasma CD133+ MP levels increase in a CD39-dependent manner during experimental acute liver injury. Increased levels of CD39+ MP are differentially noted in patients with liver injury. Further research is needed to determine whether MP fluxes are secondary to pathophysiologic insults to the liver or might reflect compensatory responses.

Schmelzle, Moritz; Splith, Katrin; Andersen, Lars W.; Kornek, Miroslaw; Schuppan, Detlef; Jones-Bamman, Caitlin; Nowak, Martina; Toxavidis, Vasilis; Salhanick, Steven D.; Han, Lihui; Schulte am Esch, Jan; Jonas, Sven; Donnino, Michael W.; Robson, Simon C.

2012-01-01

18

Regulated Catalysis of Extracellular Nucleotides by Vascular CD39/ENTPD1 Is Required for Liver Regeneration  

PubMed Central

Background & Aims Little is known about how endothelial cells respond to injury, regulate hepatocyte turnover and reconstitute the hepatic vasculature. We aimed to determine the effects of the vascular ectonucleotidase CD39 on sinusoidal endothelial cell responses following partial hepatectomy and to dissect purinergic and growth factor interactions in this model. Methods Parameters of liver injury and regeneration, as well as the kinetics of hepatocellular and sinusoidal endothelial cell proliferation, were assessed following partial hepatectomy in mice that do not express CD39, that do not express ATP/UTP receptor P2Y2, and in controls. The effects of extracellular ATP on vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and interleukin-6 responses were determined in vivo and in vitro. Phosphorylation of the endothelial VEGF receptor in response to extracellular nucleotides and growth factors was assessed in vitro. Results After partial hepatectomy, expression of the vascular ectonucleotidase CD39 increased on sinusoidal endothelial cells. Targeted disruption of CD39 impaired hepatocellular regeneration, reduced angiogenesis, and increased hepatic injury, resulting in pronounced vascular endothelial apoptosis, and decreased survival. Decreased HGF release by sinusoidal endothelial cells, despite high levels of VEGF, reduced paracrine stimulation of hepatocytes. Failure of VEGF receptor-2/KDR transactivation by extracellular nucleotides on CD39-null endothelial cells was associated with P2Y2 receptor desensitization. Conclusions Regulated phosphohydrolysis of extracellular nucleotides by CD39 coordinates both hepatocyte and endothelial cell proliferation following partial hepatectomy. Lack of CD39 activity is associated with decreased hepatic regeneration and failure of vascular reconstitution.

BELDI, GUIDO; WU, YAN; SUN, XIAOFENG; IMAI, MASATO; ENJYOJI, KEIICHI; CSIZMADIA, EVA; CANDINAS, DANIEL; ERB, LAURIE; ROBSON, SIMON C.

2010-01-01

19

Increased CD39 expression on CD4(+) T lymphocytes has clinical and prognostic significance in chronic lymphocytic leukemia.  

PubMed

Chronic lymphocytic leukemia (CLL) cells depend on their microenvironment for proliferation and survival. Ectonucleotidase CD39 has anti-inflammatory properties as it hydrolyzes proinflammatory extracellular ATP, generates anti-inflammatory adenosine, and also protects regulatory T cells from ATP-induced cell death. In this study, we investigated the clinical significance of CD39 expression on CD4(+) T cells in 62 patients with CLL as well as its compartmental regulation and explored the possible mechanisms for its induction. Compared to healthy individuals, CD4(+)CD39(+) lymphocytes were increased in the peripheral blood of patients with CLL and correlated with the advanced stage of disease. CD4(+)CD39(+) cells were also higher in patients with CLL, who needed therapeutic intervention, and in those who had unmutated immunoglobulin heavy chain variable region gene, were ZAP70(+) or had ?2-microglobulin levels of >3 g/L. There were more CD4(+)CD39(+) lymphocytes in the bone marrow compartment than in the peripheral blood, and in vitro studies showed that CD39 can be induced on CD4(+) cells by exposure to ATP or indirectly, following B cell receptor engagement. This may support the notion that the leukemic cells contribute to create an immune-subversive environment, and perhaps to a poorer prognosis. CD39(+) may also serve as a future target for the development of novel therapies with immune-modulating antitumor agents in CLL. PMID:22349724

Perry, Chava; Hazan-Halevy, Inbal; Kay, Sigi; Cipok, Michal; Grisaru, Dan; Deutsch, Varda; Polliack, Aaron; Naparstek, Elizabeth; Herishanu, Yair

2012-08-01

20

CD39 is highly involved in mediating the suppression activity of tumor-infiltrating CD8+ T regulatory lymphocytes.  

PubMed

CD39 is an ectoenzyme, present on different immune cell subsets, which mediates immunosuppressive functions catalyzing ATP degradation. It is not known whether CD39 is expressed and implicated in the activity of CD8+ regulatory T lymphocytes (Treg). In this study, CD39 expression and function was analyzed in both CD8+ and CD4+CD25(hi) Treg from the peripheral blood of healthy donors as well as from tumor specimens. CD39 was found expressed by both CD8+ (from the majority of healthy donors and tumor patients) and CD4+CD25(hi) Treg, and CD39 expression correlated with suppression activity mediated by CD8+ Treg. Importantly, CD39 counteraction remarkably inhibited the suppression activity of CD8+ Treg (both from peripheral blood and tumor microenvironment) suggesting that CD39-mediated inhibition constitutes a prevalent hallmark of their function. Collectively, these findings, unveiling a new mechanism of action for CD8+ Treg, provide new knowledge on intratumoral molecular pathways related to tumor immune escape, which could be exploited in the future for designing new biological tools for anticancer immune intervention. PMID:23359087

Parodi, Alessia; Battaglia, Florinda; Kalli, Francesca; Ferrera, Francesca; Conteduca, Giuseppina; Tardito, Samuele; Stringara, Silvia; Ivaldi, Federico; Negrini, Simone; Borgonovo, Giacomo; Simonato, Alchiede; Traverso, Paolo; Carmignani, Giorgio; Fenoglio, Daniela; Filaci, Gilberto

2013-05-01

21

Defective renal water handling in transgenic mice over-expressing human CD39/NTPDase1.  

PubMed

Ectonucleoside triphosphate diphosphohydrolase-1 hydrolyzes extracellular ATP and ADP to AMP. Previously, we showed that CD39 is expressed at several sites within the kidney and thus may impact the availability of type 2 purinergic receptor (P2-R) ligands. Because P2-Rs appear to regulate urinary concentrating ability, we have evaluated renal water handling in transgenic mice (TG) globally overexpressing hCD39. Under basal conditions, TG mice exhibited significantly impaired urinary concentration and decreased protein abundance of AQP2 in the kidney compared with wild-type (WT) mice. Urinary excretion of total nitrates/nitrites was significantly higher in TG mice, but the excretion of AVP or PGE(2) was equivalent to control WT mice. There were no significant differences in electrolyte-free water clearance or fractional excretion of sodium. Under stable hydrated conditions (gelled diet feeding), the differences between the WT and TG mice were negated, but the decrease in urine osmolality persisted. When water deprived, TG mice failed to adequately concentrate urine and exhibited impaired AVP responses. However, the increases in urinary osmolalities in response to subacute dDAVP or chronic AVP treatment were similar in TG and WT mice. These observations suggest that TG mice have impaired urinary concentrating ability despite normal AVP levels. We also note impaired AVP release in response to water deprivation but that TG kidneys are responsive to exogenous dDAVP or AVP. We infer that heightened nucleotide scavenging by increased levels of CD39 altered the release of endogenous AVP in response to dehydration. We propose that ectonucleotidases and modulated purinergic signaling impact urinary concentration and indicate potential utility of targeted therapy for the treatment of water balance disorders. PMID:22622462

Zhang, Yue; Morris, Kaiya L; Sparrow, Shannon K; Dwyer, Karen M; Enjyoji, Keiichi; Robson, Simon C; Kishore, Bellamkonda K

2012-08-01

22

Defective renal water handling in transgenic mice over-expressing human CD39/NTPDase1  

PubMed Central

Ectonucleoside triphosphate diphosphohydrolase-1 hydrolyzes extracellular ATP and ADP to AMP. Previously, we showed that CD39 is expressed at several sites within the kidney and thus may impact the availability of type 2 purinergic receptor (P2-R) ligands. Because P2-Rs appear to regulate urinary concentrating ability, we have evaluated renal water handling in transgenic mice (TG) globally overexpressing hCD39. Under basal conditions, TG mice exhibited significantly impaired urinary concentration and decreased protein abundance of AQP2 in the kidney compared with wild-type (WT) mice. Urinary excretion of total nitrates/nitrites was significantly higher in TG mice, but the excretion of AVP or PGE2 was equivalent to control WT mice. There were no significant differences in electrolyte-free water clearance or fractional excretion of sodium. Under stable hydrated conditions (gelled diet feeding), the differences between the WT and TG mice were negated, but the decrease in urine osmolality persisted. When water deprived, TG mice failed to adequately concentrate urine and exhibited impaired AVP responses. However, the increases in urinary osmolalities in response to subacute dDAVP or chronic AVP treatment were similar in TG and WT mice. These observations suggest that TG mice have impaired urinary concentrating ability despite normal AVP levels. We also note impaired AVP release in response to water deprivation but that TG kidneys are responsive to exogenous dDAVP or AVP. We infer that heightened nucleotide scavenging by increased levels of CD39 altered the release of endogenous AVP in response to dehydration. We propose that ectonucleotidases and modulated purinergic signaling impact urinary concentration and indicate potential utility of targeted therapy for the treatment of water balance disorders.

Zhang, Yue; Morris, Kaiya L.; Sparrow, Shannon K.; Dwyer, Karen M.; Enjyoji, Keiichi; Robson, Simon C.

2012-01-01

23

Human CD4(+) CD39(+) regulatory T cells produce adenosine upon co-expression of surface CD73 or contact with CD73(+) exosomes or CD73(+) cells.  

PubMed

While murine CD4(+) CD39(+) regulatory T cells (Treg ) co-express CD73 and hydrolyze exogenous (e) adenosine triphosphate (ATP) to immunosuppressive adenosine (ADO), surface co-expression of CD73 on human circulating CD4(+) CD39(+) Treg is rare. Therefore, the ability of human Treg to produce and utilize ADO for suppression remains unclear. Using mass spectrometry, we measured nucleoside production by subsets of human CD4(+) CD39(+) and CD4(+) CD39(-)CD73(+) T cells or CD19(+) B cells isolated from blood of 30 volunteers and 14 cancer patients. CD39 and CD73 expression was evaluated by flow cytometry, Western blots, confocal microscopy or reverse transcription-polymerase chain reaction (RT-PCR). Circulating CD4(+) CD39(+) Treg which hydrolyzed eATP to 5'-AMP contained few intracytoplasmic granules and had low CD73?mRNA levels. Only ?1% of these Treg were CD39(+) CD73(+) . In contrast, CD4(+) CD39(neg) CD73(+) T cells contained numerous CD73(+) granules in the cytoplasm and strongly expressed surface CD73. In vitro-generated Treg (Tr1) and most B cells were CD39(+) CD73(+) . All these CD73(+) T cell subsets and B cells hydrolyzed 5'-AMP to ADO. Exosomes isolated from plasma of normal control (NC) or cancer patients carried enzymatically active CD39 and CD73(+) and, when supplied with eATP, hydrolyzed it to ADO. Only CD4(+) CD39(+) Treg co-incubated with CD4(+) CD73(+) T cells, B cells or CD39(+) CD73(+) exosomes produced ADO. Thus, contact with membrane-tethered CD73 was sufficient for ADO production by CD4(+) CD39(+) Treg . In microenvironments containing CD4(+) CD73(+) T cells, B cells or CD39(+) CD73(+) exosomes, CD73 is readily available to CD4(+) CD39(+) CD73(neg) Treg for the production of immunosuppressive ADO. PMID:24749746

Schuler, P J; Saze, Z; Hong, C-S; Muller, L; Gillespie, D G; Cheng, D; Harasymczuk, M; Mandapathil, M; Lang, S; Jackson, E K; Whiteside, T L

2014-08-01

24

Delayed targeting of CD39 to activated platelet GPIIb/IIIa via a single-chain antibody: breaking the link between antithrombotic potency and bleeding?  

PubMed

The ecto-nucleoside triphosphate diphosphohydrolase CD39 represents a promising antithrombotic therapeutic. It degrades adenosine 5'-diphosphate (ADP), a main platelet activating/recruiting agent. We hypothesized that delayed enrichment of CD39 on developing thrombi will allow for a low and safe systemic concentration and thus avoid bleeding. We use a single-chain antibody (scFv, specific for activated GPIIb/IIIa) for targeting CD39. This should allow delayed enrichment on growing thrombi but not on the initial sealing layer of platelets, which do not yet express activated GPIIb/IIIa. CD39 was recombinantly fused to an activated GPIIb/IIIa-specific scFv (targ-CD39) and a nonfunctional scFv (non-targ-CD39). Targ-CD39 was more effective at preventing ADP-induced platelet activation than non-targ-CD39. In a mouse carotid artery thrombosis model, non-targ-CD39, although protective against vessel occlusion, was associated with significant bleeding on tail transection. In contrast, targ-CD39 concentrated at the thrombus site; hence, a dose ?10 times less of CD39 prevented vessel occlusion to a similar extent as high-dose non-targ-CD39, without prolonged bleeding time. An equimolar dose of non-targ-CD39 at this low concentration was ineffective at preventing vessel occlusion. Thus, delayed targeting of CD39 via scFv to activated platelets provides strong antithrombotic potency and yet prevents bleeding and thereby promotes CD39 toward clinical use. PMID:23380744

Hohmann, Jan David; Wang, Xiaowei; Krajewski, Stefanie; Selan, Carly; Haller, Carolyn A; Straub, Andreas; Chaikof, Elliot L; Nandurkar, Harshal H; Hagemeyer, Christoph E; Peter, Karlheinz

2013-04-18

25

Delayed targeting of CD39 to activated platelet GPIIb/IIIa via a single-chain antibody: breaking the link between antithrombotic potency and bleeding?  

PubMed Central

The ecto-nucleoside triphosphate diphosphohydrolase CD39 represents a promising antithrombotic therapeutic. It degrades adenosine 5?-diphosphate (ADP), a main platelet activating/recruiting agent. We hypothesized that delayed enrichment of CD39 on developing thrombi will allow for a low and safe systemic concentration and thus avoid bleeding. We use a single-chain antibody (scFv, specific for activated GPIIb/IIIa) for targeting CD39. This should allow delayed enrichment on growing thrombi but not on the initial sealing layer of platelets, which do not yet express activated GPIIb/IIIa. CD39 was recombinantly fused to an activated GPIIb/IIIa-specific scFv (targ-CD39) and a nonfunctional scFv (non–targ-CD39). Targ-CD39 was more effective at preventing ADP-induced platelet activation than non–targ-CD39. In a mouse carotid artery thrombosis model, non–targ-CD39, although protective against vessel occlusion, was associated with significant bleeding on tail transection. In contrast, targ-CD39 concentrated at the thrombus site; hence, a dose ?10 times less of CD39 prevented vessel occlusion to a similar extent as high-dose non–targ-CD39, without prolonged bleeding time. An equimolar dose of non–targ-CD39 at this low concentration was ineffective at preventing vessel occlusion. Thus, delayed targeting of CD39 via scFv to activated platelets provides strong antithrombotic potency and yet prevents bleeding and thereby promotes CD39 toward clinical use.

Hohmann, Jan David; Wang, Xiaowei; Krajewski, Stefanie; Selan, Carly; Haller, Carolyn A.; Straub, Andreas; Chaikof, Elliot L.; Nandurkar, Harshal H.; Hagemeyer, Christoph E.

2013-01-01

26

Genetic analysis of an allergic rhinitis cohort reveals an intercellular epistasis between FAM134B and CD39  

PubMed Central

Background Extracellular ATP is a pro-inflammatory molecule released by damaged cells. Regulatory T cells (Treg) can suppress inflammation by hydrolysing this molecule via ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1), also termed as CD39. Multiple studies have reported differences in CD39+ Treg percentages in diseases such as multiple sclerosis, Hepatitis B and HIV-1. In addition, CD39 polymorphisms have been implicated in immune-phenotypes such as susceptibility to inflammatory bowel disease and AIDS progression. However none of the studies published so far has linked disease-associated variants with differences in CD39 Treg surface expression. This study aims at identifying variants affecting CD39 expression on Treg and at evaluating their association with allergic rhinitis, a disease characterized by a strong Treg involvement. Methods Cohorts consisting of individuals of different ethnicities were employed to identify any association of CD39 variants to surface expression. Significant variant(s) were tested for disease association in a published GWAS cohort by one-locus and two-locus genetic analyses based on logistic models. Further functional characterization was performed using existing microarray data and quantitative RT-PCR on sorted cells. Results Our study shows that rs7071836, a promoter SNP in the CD39 gene region, affects the cell surface expression on Treg cells but not on other CD39+ leukocyte subsets. Epistasis analysis revealed that, in conjunction with a SNP upstream of the FAM134B gene (rs257174), it increased the risk of allergic rhinitis (P?=?1.98?×?10-6). As a promoter SNP, rs257174 controlled the expression of the gene in monocytes but, notably, not in Treg cells. Whole blood transcriptome data of three large cohorts indicated an inverse relation in the expression of the two proteins. While this observation was in line with the epistasis data, it also implied that a functional link must exist. Exposure of monocytes to extracellular ATP resulted in an up-regulation of FAM134B gene expression, suggesting that extracellular ATP released from damaged cells represents the connection for the biological interaction of CD39 on Treg cells with FAM134B on monocytes. Conclusions The interplay between promoter SNPs of CD39 and FAM134B results in an intercellular epistasis which influences the risk of a complex inflammatory disease.

2014-01-01

27

Expression of CD39 mRNA is altered in the peripheral blood of patients with allergic asthma  

PubMed Central

The ectoenzyme CD39 hydrolyzes extracellular adenosine 5?-triphosphate (ATP), which possesses pro-inflammatory properties. However, the role of CD39 in allergic asthma has not been fully elucidated. A total of 18 patients with persistent asthma who were allergic to house dust mites and 19 healthy volunteers were enrolled in this study. The expression of CD39, GATA3, RAR-related orphan receptor ? (ROR-?t) and forkhead box P3 (FoxP3) mRNA in peripheral blood mononuclear cells (PBMCs) was determined by SYBR-Green I quantitative polymerase chain reaction (qPCR). The cytokines interleukin (IL)-4, IL-17A, transforming growth factor ? (TGF-?) and DP.sIgE were detected by enzyme-linked immunosorbent assay. Our data demonstrated that the expression of CD39 mRNA in PBMCs from asthmatic patients was significantly lower compared to that in normal controls [(1.49±0.59)×10?3 vs. (2.17±0.77)×10?3, respectively; P<0.01]. CD39 mRNA was negatively correlated with serum IL-4, IL-17A and GATA3 expression (r=?0.468, P<0.05; r=?0.550, P<0.05; and r=?0.424, P<0.01, respectively) and positively correlated with FoxP3 and TGF-? expression (r=0.373, P<0.05; and r=0.425, P<0.05, respectively). There was no obvious correlation between CD39 and ROR-?t expression (r=?0.259, P=0.122). These data suggested that CD39 mRNA expression was downregulated in allergic asthma, which was positively correlated with serum IL-4, IL-17A and GATA3 expression and negatively correlated with serum TGF-? and FoxP3 expression, whereas there was no correlation with ROR-?t. Therefore, it was hypothesized that CD39 may participate in the occurrence and progression of allergic asthma.

WANG, LIN-LIN; TANG, PING-HUA; SHI, CHAO-GUO; WAN, YING-HUAN; TANG, WEI; HOU, XIA-XIAO; PAN, NA-LI; SHI, YU-BAO; TAO, QIN-LIAN

2014-01-01

28

The Expression Level of Ecto-NTP Diphosphohydrolase1/CD39 Modulates Exocytotic and Ischemic Release of Neurotransmitters in a Cellular Model of Sympathetic Neurons  

PubMed Central

Once released, norepinephrine is removed from cardiac synapses via reuptake into sympathetic nerves, whereas transmitter ATP is catabolized by ecto-NTP diphosphohydrolase 1 (E-NTPDase1)/CD39, an ecto-ATPase. Because ATP is known to modulate neurotransmitter release at prejunctional sites, we questioned whether this action may be ultimately controlled by the expression of E-NTPDase1/CD39 at sympathetic nerve terminals. Accordingly, we silenced E-NTPDase1/CD39 expression in nerve growth factor-differentiated PC12 cells, a cellular model of sympathetic neuron, in which dopamine is the predominant catecholamine. We report that E-NTPDase1/CD39 deletion markedly increases depolarization-induced exocytosis of ATP and dopamine and increases ATP-induced dopamine release. Moreover, overexpression of E-NTPDase1/CD39 resulted in enhanced removal of exogenous ATP, a marked decrease in exocytosis of ATP and dopamine, and a large decrease in ATP-induced dopamine release. Administration of a recombinant form of E-NTPDase1/CD39 reproduced the effects of E-NTPDase1/CD39 overexpression. Exposure of PC12 cells to simulated ischemia elicited a release of ATP and dopamine that was markedly increased in E-NTPDase1/CD39-silenced cells and decreased in E-NTPDase1/CD39-overexpressing cells. Therefore, transmitter ATP acts in an autocrine manner to promote its own release and that of dopamine, an action that is controlled by the level of E-NTPDase1/CD39 expression. Because ATP availability greatly increases in myocardial ischemia, recombinant E-NTPDase1/CD39 therapeutically used may offer a novel approach to reduce cardiac dysfunctions caused by excessive catecholamine release.

Corti, Federico; Olson, Kim E.; Marcus, Aaron J.

2011-01-01

29

Distribution of ecto-nucleotidases in mouse sensory circuits suggests roles for nucleoside triphosphate diphosphohydrolase-3 in nociception and mechanoreception  

Microsoft Academic Search

Nucleotide-activated P2X channels and P2Y metabotropic receptors participate in nociceptive signaling. Agonist availability is regulated by nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), -2, -3, and -8, a family of enzymes that hydrolyze extracellular ATP to generate ADP (a P2Y agonist) and AMP. They provide a major source of extracellular AMP, the substrate for adenosine production by ecto-5?-nucleotidase (NT5E), and thereby regulate adenosine

H. O. Vongtau; E. G. Lavoie; J. Sévigny; D. C. Molliver

2011-01-01

30

Distribution of ecto-nucleotidases in mouse sensory circuits suggests roles for nucleoside triphosphate diphosphohydrolase-3 in nociception and mechanoreception.  

PubMed

Nucleotide-activated P2X channels and P2Y metabotropic receptors participate in nociceptive signaling. Agonist availability is regulated by nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), -2, -3, and -8, a family of enzymes that hydrolyze extracellular ATP to generate ADP (a P2Y agonist) and AMP. They provide a major source of extracellular AMP, the substrate for adenosine production by ecto-5'-nucleotidase (NT5E), and thereby regulate adenosine (P1) receptor signaling. NTPDases vary in their efficiency of tri- and diphosphate hydrolysis; therefore, which family members are expressed impacts nucleotide availability and half-life. This study employed enzyme activity histochemistry to examine the distribution of ATPase activity and immunohistochemistry for NTPDase1, 2, 3, and 8 in dorsal root ganglion (DRG) and spinal cord. Nucleotidase activity was robust in spinal dorsal horn, confirming that nociceptive pathways are a major site of nucleotide transmission. In DRG, extensive staining revealed ATPase activity in a subset of neurons and in non-neuronal cells. mRNA for NTPDase1-3, but not NTPDase8, was detected in lumbar DRG and spinal cord. Immunoreactivity for NTPDase3 closely matched the distribution of ATPase activity, labeling DRG central projections in the dorsal root and superficial dorsal horn, as well as intrinsic spinal neurons concentrated in lamina II. In DRG, NTPDase3 co-localized with markers of nociceptors and with NT5E. In addition, labeling of a subset of larger-diameter neurons in DRG was consistent with intense staining of Meissner corpuscle afferents in glabrous skin. Merkel cells and terminal Schwann cells of hair follicle afferents were also labeled, but the axons themselves were negative. We propose that NTPDase3 is a key regulator of nociceptive signaling that also makes an unexpected contribution to innocuous tactile sensation. PMID:21807070

Vongtau, H O; Lavoie, E G; Sévigny, J; Molliver, D C

2011-10-13

31

CD39 is a negative regulator of P2X7-mediated inflammatory cell death in mast cells  

PubMed Central

Background Mast cells (MCs) are major contributors to an inflammatory milieu. One of the most potent drivers of inflammation is the cytokine IL-1?, which is produced in the cytoplasm in response to danger signals like LPS. Several controlling mechanisms have been reported which limit the release of IL-1?. Central to this regulation is the NLRP3 inflammasome, activation of which requires a second danger signal with the capacity to subvert the homeostasis of lysosomes and mitochondria. High concentrations of extracellular ATP have the capability to perturb the plasma membrane by activation of P2X7 channels and serve as such a danger signal. In this study we investigate the role of P2X7 channels and the ecto-5´-nucleotidase CD39 in ATP-triggered release of IL-1? from LPS-treated mast cells. Results We report that in MCs CD39 sets an activation threshold for the P2X7-dependent inflammatory cell death and concomitant IL-1? release. Knock-out of CD39 or stimulation with non-hydrolysable ATP led to a lower activation threshold for P2X7-dependent responses. We found that stimulation of LPS-primed MCs with high doses of ATP readily induced inflammatory cell death. Yet, cell death-dependent release of IL-1? yielded only minute amounts of IL-1?. Intriguingly, stimulation with low ATP concentrations augmented the production of IL-1? in LPS-primed MCs in a P2X7-independent but caspase-1-dependent manner. Conclusion Our study demonstrates that the fine-tuned interplay between ATP and different surface molecules recognizing or modifying ATP can control inflammatory and cell death decisions.

2014-01-01

32

Segregated regulatory CD39+CD4+ T cell function: TGF-?-producing Foxp3- and IL-10-producing Foxp3+ cells are interdependent for protection against collagen-induced arthritis.  

PubMed

Oral immunization with a Salmonella vaccine vector expressing enterotoxigenic Escherichia coli colonization factor Ag I (CFA/I) can protect against collagen-induced arthritis (CIA) by dampening IL-17 and IFN-? via enhanced IL-4, IL-10, and TGF-?. To identify the responsible regulatory CD4(+) T cells making the host refractory to CIA, Salmonella-CFA/I induced CD39(+)CD4(+) T cells with enhanced apyrase activity relative to Salmonella vector-immunized mice. Adoptive transfer of vaccine-induced CD39(+)CD4(+) T cells into CIA mice conferred complete protection, whereas CD39(-)CD4(+) T cells did not. Subsequent analysis of vaccinated Foxp3-GFP mice revealed the CD39(+) T cells were composed of Foxp3-GFP(-) and Foxp3-GFP(+) subpopulations. Although each adoptively transferred Salmonella-CFA/I-induced Foxp3(-) and Foxp3(+)CD39(+)CD4(+) T cells could protect against CIA, each subset was not as efficacious as total CD39(+)CD4(+) T cells, suggesting their interdependence for optimal protection. Cytokine analysis revealed Foxp3(-) CD39(+)CD4(+) T cells produced TGF-?, and Foxp3(+)CD39(+)CD4(+) T cells produced IL-10, showing a segregation of function. Moreover, donor Foxp3-GFP(-) CD4(+) T cells converted to Foxp3-GFP(+) CD39(+)CD4(+) T cells in the recipients, showing plasticity of these regulatory T cells. TGF-? was found to be essential for protection because in vivo TGF-? neutralization reversed activation of CREB and reduced the development of CD39(+)CD4(+) T cells. Thus, CD39 apyrase-expressing CD4(+) T cells stimulated by Salmonella-CFA/I are composed of TGF-?-producing Foxp3(-) CD39(+)CD4(+) T cells and support the stimulation of IL-10-producing Foxp3(+) CD39(+)CD4(+) T cells. PMID:21967895

Kochetkova, Irina; Thornburg, Theresa; Callis, Gayle; Pascual, David W

2011-11-01

33

IL-35 Stimulation of CD39+ Regulatory T Cells Confers Protection against Collagen II-Induced Arthritis via the Production of IL-10  

PubMed Central

IL-35 is produced by regulatory T cells, and this novel cytokine can downregulate Th17 cell development and inhibit autoimmune inflammation. In this work, an rIL-35, as a single-chain fusion between murine IL-12p35 and EBV-induced gene 3, was expressed in yeast. This rIL-35 inhibited OVA-specific cellular and Ab responses in OVA-challenged recipients of DO11.10 CD4+ T cells. Likewise, IL-35 inhibited clinical manifestation of collagen-induced arthritis or could cease further disease exacerbation upon initiation of IL-35 treatment. Exogenous IL-35 treatments suppressed Th1 and Th17 cells and promoted CD39 expression by CD4+ T cells. Sorted CD25?CD39+CD4+ T cells from IL-35–treated mice produced IL-10 and, upon adoptive transfer, were sufficiently potent to inhibit subsequent development of inflammation in mice with collagen-induced arthritis, whereas sorted CD25+CD39+ CD4+ T cells showed reduced potency. IL-35 treatments of IL-10?/? mice failed to induce protective CD39+CD4+ T cells, demonstrating the effector role of IL-10 by IL-35 immunosuppression.

Kochetkova, Irina; Golden, Sarah; Holderness, Kathryn; Callis, Gayle; Pascual, David W.

2011-01-01

34

Low-Dose Levodopa Protects Nerve Cells from Oxidative Stress and Up-Regulates Expression of pCREB and CD39  

PubMed Central

Objective This study aimed to investigate the influence of low-dose levodopa (L-DOPA) on neuronal cell death under oxidative stress. Methods PC12 cells were treated with L-DOPA at different concentrations. We detected the L-DOPA induced reactive oxygen species (ROS). Meanwhile, MTT and LDH assay were performed to determine the proliferation and growth of PC12 cells with or without ROS scavenger. In addition, after pretreatment with L-DOPA at different concentrations alone or in combination with CD39 inhibitor, PC12 cells were incubated with hydrogen peroxide (H2O2) and the cell viability was evaluated by MTT and LDH assay. In addition, the expression of pCREB and CD39 was detected by immunofluorescence staining and Western blot assay in both cells and rat’s brain after L-DOPA treatment. Results After treatment with L-DOPA for 3 days, the cell proliferation and growth were promoted when the L-DOPA concentration was <30 µM, while cell proliferation was comparable to that in control group when the L-DOPA concentration was >30 µM. Low dose L-DOPA could protect the PC12 cells from H2O2 induced oxidative stress, which was compromised by CD39 inhibitor. In addition, the expression of CD39 and pCREB increased in both PC12 cells and rats’ brain after L-DOPA treatment. Conclusions L-DOPA at different concentrations has distinct influence on proliferation and growth of PC12 cells, and low dose (<30 µM) L-DOPA protects PC12 cells against oxidative stress which might be related to the up-regulation of CD39 and pCREB expression.

Fang, Min; Zhu, Xiao-Long; Zhao, Yan-Xin; Liu, Xue-Yuan

2014-01-01

35

Ectonucleotide triphosphate diphosphohydrolase-1 (CD39) mediates resistance to occlusive arterial thrombus formation after vascular injury in mice.  

PubMed

Modulation of purinergic signaling, which is critical for vascular homeostasis and the response to vascular injury, is regulated by hydrolysis of proinflammatory ATP and/or ADP by ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) to AMP, which then is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine. We report here that compared with littermate controls (wild type), transgenic mice expressing human ENTPDase-1 were resistant to the formation of an occlusive thrombus after FeCl(3)-induced carotid artery injury. Treatment of mice with the nonhydrolyzable ADP analog, adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S], negated the protection from thrombosis, consistent with a role for ADP in platelet recruitment and thrombus formation. ENTPD-1 expression decreased whole-blood aggregation after stimulation by ADP, an effect negated by adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S] stimulation, and limited the ability to maintain the platelet fibrinogen receptor, glycoprotein ?(IIb)/?(3), in a fully activated state, which is critical for thrombus formation. In vivo treatment with a CD73 antagonist, a nonselective adenosine-receptor antagonist, or a selective A(2A) or A(2B) adenosine-receptor antagonist, negated the resistance to thrombosis in transgenic mice expressing human ENTPD-1, suggesting a role for adenosine generation and engagement of adenosine receptors in conferring in vivo resistance to occlusive thrombosis in this model. In summary, our findings identify ENTPDase-1 modulation of purinergic signaling as a key determinant of the formation of an occlusive thrombus after vascular injury. PMID:22613024

Huttinger, Zachary M; Milks, Michael W; Nickoli, Michael S; Aurand, William L; Long, Lawrence C; Wheeler, Debra G; Dwyer, Karen M; d'Apice, Anthony J F; Robson, Simon C; Cowan, Peter J; Gumina, Richard J

2012-07-01

36

Metabolism of circulating ADP in the bloodstream is mediated via integrated actions of soluble adenylate kinase-1 and NTPDase1/CD39 activities  

PubMed Central

Extracellular ATP and ADP trigger inflammatory, vasodilatatory, and prothrombotic signaling events in the vasculature, and their turnover is governed by networks of membrane-associated enzymes. The contribution of soluble activities to intravascular nucleotide homeostasis remains controversial. By using thin-layer chromatographic assays, we revealed transphosphorylation of [?-32P]ATP and AMP by human and murine sera, which was progressively inhibited by specific adenylate kinase (AK) inhibitor Ap5A. This phosphotransfer reaction was diminished markedly in serum from knockout mice lacking the major AK isoform, AK1, and in human serum immunodepleted of AK1. We also showed that ?75% ADP in cell-free serum is metabolized via reversible AK1 reaction 2ADP ? ATP + AMP. The generated ATP and AMP are then metabolized through the coupled nucleotide pyrophosphatase/phosphodiesterase and 5?-nucleotidase/CD73 reactions, respectively. Constitutive presence of another nucleotide-converting enzyme, nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, known as CD39), was ascertained by the relative deficiency of serum from CD39-null mice to dephosphorylate [3H]ADP and [?-32P]ATP, and also by diminished [3H]ADP hydrolysis by human serum pretreated with NTPDase1 inhibitors, POM-1 and ARL-67156. In summary, we have identified hitherto unrecognized soluble forms of AK1 and NTPDase1/CD39 that contribute in the active cycling between the principal platelet-recruiting agent ADP and other circulating nucleotides.—Yegutkin, G. G., Wieringa, B., Robson, S. C., Jalkanen, S. Metabolism of circulating ADP in the bloodstream is mediated via integrated actions of soluble adenylate kinase-1 and NTPDase1/CD39 activities

Yegutkin, Gennady G.; Wieringa, Be; Robson, Simon C.; Jalkanen, Sirpa

2012-01-01

37

Metabolism of circulating ADP in the bloodstream is mediated via integrated actions of soluble adenylate kinase-1 and NTPDase1/CD39 activities.  

PubMed

Extracellular ATP and ADP trigger inflammatory, vasodilatatory, and prothrombotic signaling events in the vasculature, and their turnover is governed by networks of membrane-associated enzymes. The contribution of soluble activities to intravascular nucleotide homeostasis remains controversial. By using thin-layer chromatographic assays, we revealed transphosphorylation of [?-(32)P]ATP and AMP by human and murine sera, which was progressively inhibited by specific adenylate kinase (AK) inhibitor Ap(5)A. This phosphotransfer reaction was diminished markedly in serum from knockout mice lacking the major AK isoform, AK1, and in human serum immunodepleted of AK1. We also showed that ?75% ADP in cell-free serum is metabolized via reversible AK1 reaction 2ADP ? ATP + AMP. The generated ATP and AMP are then metabolized through the coupled nucleotide pyrophosphatase/phosphodiesterase and 5'-nucleotidase/CD73 reactions, respectively. Constitutive presence of another nucleotide-converting enzyme, nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, known as CD39), was ascertained by the relative deficiency of serum from CD39-null mice to dephosphorylate [(3)H]ADP and [?-(32)P]ATP, and also by diminished [(3)H]ADP hydrolysis by human serum pretreated with NTPDase1 inhibitors, POM-1 and ARL-67156. In summary, we have identified hitherto unrecognized soluble forms of AK1 and NTPDase1/CD39 that contribute in the active cycling between the principal platelet-recruiting agent ADP and other circulating nucleotides. PMID:22637533

Yegutkin, Gennady G; Wieringa, Bé; Robson, Simon C; Jalkanen, Sirpa

2012-09-01

38

Role of the ecto-nucleotidases in the cooperative effect of adenosine and neuropeptide-S on locomotor activity in mice.  

PubMed

Activation of adenosine receptors modifies the action of classic neurotransmitters (i.e. dopamine, glutamate and acetylcholine) and other neuromodulators, like vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP) and neuropeptide S (NPS). Similarly to adenosine, NPS is involved in the regulation of stimulus and response to fear and arousal. Thus, the present study investigates the effects of NPS on locomotor activity in mice treated with or without ?,?-methylene adenosine 5'-diphosphate (AOPCP), the inhibitor of ecto-5'-nucleotidase. Additionally, we evaluate the activity of ecto-5'-nucleotidase in brain slices of mice treated with or without NPS. Male adult CF-1 mice received i.c.v. NPS as 0.1 nmol injection with or without pre-treatment with 1 nmol ?,?-methylene adenosine 5'-diphosphate (AOPCP), the selective inhibitor of ecto-5'-nucleotidase, to evaluate locomotor activity. In another set of experiments, mice received i.c.v. infusion of 0.1 nmol NPS to assay enzymatic activity in brain slices. The results demonstrated that the pre-treatment with AOPCP, which was inactive per se, prevented NPS-induced hyperlocomotion in mice. The dose of 0.1 nmol NPS was efficient to induce hyperlocomotion in animals during the observation period in the activity cage. Regarding enzymatic activity, i.c.v. NPS injection did not induce any significant alterations in ATP and AMP hydrolysis in striatum and hippocampus brain slices of mice. The present study shows that the hyperlocomotor effect of NPS depends on the ecto-5'-nucleotidase activity. PMID:21741987

Pacheco, Robson; Pescador, Bruna Bardini; Mendonça, Bruna Pescador; Ramos, Saulo Fábio; Guerrini, Remo; Calo', Girolamo; de Andrade, Vanessa Moraes; Gavioli, Elaine Cristina; Boeck, Carina Rodrigues

2011-10-01

39

Human antigen-specific CD4(+) CD25(+) CD134(+) CD39(+) T cells are enriched for regulatory T cells and comprise a substantial proportion of recall responses.  

PubMed

Human Ag-specific CD4(+) T cells can be detected by their dual expression of CD134 (OX40) and CD25 after a 44 hours stimulation with cognate Ag. We show that surface expression of CD39 on Ag-specific cells consistently identifies a substantial population of CD4(+) CD25(+) CD134(+) CD39(+) T cells that have a Treg-cell-like phenotype and mostly originate from bulk memory CD4(+) CD45RO(+) CD127(low) CD25(high) CD39(+) Treg cells. Viable, Ag-specific CD25(+) CD134(+) CD39(+) T cells could be expanded in vitro as cell lines and clones, and retained high Forkhead Box Protein 3, CTLA-4 and CD39 expression, suppressive activity and Ag specificity. We also utilised this combination of cell surface markers to measure HIV-Gag responses in HIV(+) patients before and after anti-retroviral therapy (ART). Interestingly, we found that the percentage of CD39(-) cells within baseline CD4(+) T-cell responses to HIV-Gag was negatively correlated with HIV viral load pre-ART and positively correlated with CD4(+) T-cell recovery over 96 weeks of ART. Collectively, our data show that Ag-specific CD4(+) CD25(+) CD134(+) CD39(+) T cells are highly enriched for Treg cells, form a large component of recall responses and maintain a Treg-cell-like phenotype upon in vitro expansion. Identification and isolation of these cells enables the role of Treg cells in memory responses to be further defined and provides a development pathway for novel therapeutics. PMID:24752698

Seddiki, Nabila; Cook, Laura; Hsu, Denise C; Phetsouphanh, Chansavath; Brown, Kai; Xu, Yin; Kerr, Stephen J; Cooper, David A; Munier, C Mee Ling; Pett, Sarah; Ananworanich, Jintanat; Zaunders, John; Kelleher, Anthony D

2014-06-01

40

Anti-CD39 and anti-CD73 antibodies A1 and 7G2 improve targeted therapy in ovarian cancer by blocking adenosine-dependent immune evasion  

PubMed Central

The ectonucleotidases CD39 and CD73 degrade ATP to adenosine which inhibits immune responses via the A2A adenosine receptor (ADORA2A) on T and NK cells. The current study investigates the potential therapeutic use of the specific anti CD39- and anti CD73-antibodies A1 (CD39) and 7G2 (CD73) as these two ectonucleotidases are overexpressed in ovarian cancer (OvCA). As expected, NK cell cytotoxicity against the human ovarian cancer cell lines OAW-42 or SK-OV-3 was significantly increased in the presence of A1 or 7G2 antibody. While this might partly be due to antibody-dependent cell-mediated cytotoxicity, a luciferase-dependent assay for quantifying biologically active adenosine further showed that A1 and 7G2 can inhibit CD39 and CD73-dependent adenosine-generation. In turn, the reduction in adenosine levels achieved by addition of A1 and 7G2 to OAW-42 or SK-OV-3 cells was found to de-inhibit the proliferation of CD4+ T cells in coculture with OvCA cells. Likewise, blocking of CD39 and CD73 on OvCA cells via A1 and 7G2 led to an increased cytotoxicity of alloreactive primed T cells. Thus, antibodies like A1 and 7G2 could improve targeted therapy in ovarian cancer not only by specifically labeling overexpressed antigens but also by blocking adenosine-dependent immune evasion in this immunogenic malignancy.

Hausler, Sebastian FM; del Barrio, Itsaso Montalban; Diessner, Joachim; Stein, Roland G; Strohschein, Jenny; Honig, Arnd; Dietl, Johannes; Wischhusen, Jorg

2014-01-01

41

Hematologic phenotype of the mutations IVS1-n6 (T-->C), IVS1-n110 (G-->A), and CD39 (C-->T) in carriers of beta-thalassemia in Greece.  

PubMed

The hematologic phenotype was characterized in heterozygotes for three of the most common beta-thalassemia mutations in the Greek population. The study included 17 carriers of beta++ IVS1-n6 (T-->C), 21 carriers of beta+ IVS1-n110 (G-->A), and 17 carriers of beta 0 CD39 (C-->T). The 55 beta-thalassemia heterozygotes were selected from among parents of patients on regular transfusion regimens, and the beta-thalassemia mutation was identified by means of the polymerase chain reaction to amplify the appropriate region of the beta-globin gene and then by allele-specific oligonucleotide hybridization. The assessment of hematologic phenotype included complete blood count and quantitation of hemoglobin HbA2 and HbF and of the globin chain biosynthesis ratio. Comparison and statistical analysis of the hematologic parameters for the three mutations demonstrated no consistent correlation among the three mutations relative to Hb levels, hematocrit, and red cell indices, although heterozygotes for the IVS1-n6 mutation produce red blood cells with slightly higher mean corpuscular volume; significantly lower values of HbA2 (mean, 3.81% +/- 0.62% with four values less than 3.60%) in IVS1-n6 heterozygotes compared with IVS1-n110 heterozygotes (mean, 4.69% +/- 0.48%) and CD39 heterozygotes (mean, 4.75% +/- 0.50%, P < 0.001); and significantly higher HbF levels in CD39 heterozygotes (mean, 2.31% +/- 1.52%) compared with IVS1-n6 heterozygotes (mean, 0.79% +/- 0.45%, P < 0.01) and IVS1-n110 heterozygotes (mean, 1.17% +/- 0.75%, P < 0.01). With respect to the HbA2 levels, the findings are in agreement with previous studies in Mediterranean populations; the slightly higher levels of HbF in CD39 heterozygotes appear to be reported for the first time. PMID:7530030

Stefanis, L; Kanavakis, E; Traeger-Synodinos, J; Tzetis, M; Metaxotou-Mavromati, A; Kattamis, C

1994-01-01

42

South African Particulates  

article title:  Airborne Particulates over Southern Africa     View Larger ... the abundance of airborne particulates, or aerosols, over Southern Africa during the period August 14 - September 29, 2000. Low particle ...

2013-04-16

43

30 CFR Particulate - Underground Only  

Code of Federal Regulations, 2010 CFR

...false Underground Only Particulate Diesel Particulate Matter Mineral Resources...Quality, Radiation, Physical Agents, and Diesel Particulate Matter Radiation-Underground...1995; 71 FR 16667, Apr. 3, 2006] Diesel Particulate MatterâUnderground...

2010-07-01

44

PARTICULATE MATTER RESEARCH 02  

EPA Science Inventory

2002 PARTICULATE MATTER GPRA Goal 1: Clean Air; Objective 1.1: Ozone, PM, and SO2 NAAQS; Sub-Objective 1.1.5: Particulate Matter Research Description: In July 1997, EPA revised the National Ambient Air Quality Standard (NAAQS) for Particulate Matter (PM), recogniz...

45

Diesel particulate control  

SciTech Connect

Diesel particulates, because of their chemical composition and extremely small size, have raised health and welfare issues. Health experts have expressed concern that they contribute to or aggravate chronic lung diseases such as asthma, bronchitis and emphysema, and there is the lingering issue about the potential cancer risk from exposure to diesel particulate. Diesel particulates impair visibility, soil buildings, contribute to structural damage through corrosion and give off a pungent odor. Diesel trucks, buses and cars together are such a significant and growing source of particulate emissions. Such vehicles emit 30 to 70 times more particulate matter than gasoline vehicles equipped with catalytic converters. Diesel engines currently power the majority of larger trucks and buses. EPA predicted that, if left uncontrolled, diesel particulate from motor vehicles would increase significantly. Diesel particulate emissions from motor vehicles are particularly troublesome because they frequently are emitted directly into the breathing zone where we work and recreate. The U.S. Congress recognized the risks posed by diesel particulate and as part of the 1977 Clean Air Act Amendments established specific, technology-forcing requirements for controlling these emissions. The U.S. Environmental Protection Agency (EPA) in 1980 established particulate standards for automobiles and light trucks and in 1985, heavy trucks and buses. California, concerned that EPA standards would not adequately protect its citizens, adopted its own set of standards for passenger cars and light trucks. This paper discusses emerging technologies proposed to address the problem.

Bertelsen, F.I. (Manufacturers of Emissions Control Association, Washington, DC (US))

1988-01-01

46

Sulfate Aerosol Particulates  

NASA Astrophysics Data System (ADS)

The condensation of SO3 vapor to detrimental acid-mist occurs only after substantial flue gas cooling, usually downstream from electrostatic precipitators. This condensation is an equilibrium process depending on gas temperature and water vapor pressure. Smelter plume opacity is related to acidmist and other sulfate aerosol particulate concentration through Mie particulate scattering theory. It is possible to estimate the amounts of sulfate particulate emissions and plume opacity, particularly those resulting from anticipated changes in smelter operations and flue gas treatment. These estimates can be used to determine compliance with current or anticipated regulations on smelter particulate emissions or plume opacity.

Bartlett, Robert W.

1987-09-01

47

Pitch based foam with particulate  

DOEpatents

A thermally conductive, pitch based foam composite having a particulate content. The particulate alters the mechanical characteristics of the foam without severely degrading the foam thermal conductivity. The composite is formed by mixing the particulate with pitch prior to foaming.

Klett, James W. (Knoxville, TN)

2001-01-01

48

Particulate Air Pollution: The Particulars  

ERIC Educational Resources Information Center

Describes some of the causes and consequences of particulate air pollution. Outlines the experimental procedures for measuring the amount of particulate materials that settles from the air and for observing the nature of particulate air pollution. (JR)

Murphy, James E.

1973-01-01

49

Diesel particulate emission control  

Microsoft Academic Search

This paper reviews the emission control of particulates from diesel exhaust gases. The efficiency and exhaust emissions of diesel engines will be compared with those of otto engines (petrol engines). The formation of particulates (or “soot”), one of the main nuisances of diesel exhaust gases, will be briefly outlined. The effects of various emission components on human health and the

John P. A. Neeft; Michiel Makkee; Jacob A. Moulijn

1996-01-01

50

CONTROLLING EMISSIONS OF PARTICULATES  

EPA Science Inventory

The report gives a semi-technical overview of the contribution of particulate matter to the overall U.S. air pollution problem. It also discusses contributions of the Particulate Technology Branch of EPA's Industrial Environmental Research Laboratory at Research Triangle Park, N....

51

Particulate technology issues  

Microsoft Academic Search

Advanced systems for power generation based on coal combustion or gasification will require effective particulate control both for protection of equipment in the gas stream and for compliance with environmental regulations. These new classes of systems will require efficient removal of particles from gas streams at high temperature and high pressure. Primary candidates for particulate control are various types of

D. H. Pontius; P. Vann Bush

1992-01-01

52

Airborne particulate discriminator  

DOEpatents

A method and apparatus for rapid and accurate detection and discrimination of biological, radiological, and chemical particles in air. A suspect aerosol of the target particulates is treated with a taggant aerosol of ultrafine particulates. Coagulation of the taggant and target particles causes a change in fluorescent properties of the cloud, providing an indication of the presence of the target.

Creek, Kathryn Louise (San Diego, CA) [San Diego, CA; Castro, Alonso (Santa Fe, NM) [Santa Fe, NM; Gray, Perry Clayton (Los Alamos, NM) [Los Alamos, NM

2009-08-11

53

Particulate matter fugitive dusts  

SciTech Connect

Topics covered in this conference include: Review of EPA's cost/benefit analysis for additional regulation of surface coal mines; Particulate monitoring on the Kilauea East Rift, Hawaii, and The MEDUSA sampling system: case histories in the measurement of particulate matter with wide spectrum analysis.

Not Available

1988-01-01

54

Advances in diesel particulate control  

SciTech Connect

This book contains the proceedings on advances in diesel particulate control. Topics covered include: trapping performance of diesel particulate filters, catalyst assisted regeneration system for a diesel particulate trap, the performance of an electrostatic agglomerator as a diesel soot emission control device, and regeneration capability of wall-flow monolith diesel particulate filter with electric heater.

Not Available

1990-01-01

55

Modeling of Particulate Emissions.  

National Technical Information Service (NTIS)

Atmospheric levels of PM2.5 particulate matter near airports are increased by solid carbonaceous soot and condensable gaseous species emitted by military and commercial gas turbine aircraft engines. Carbonaceous materials are formed in the main combustor ...

M. Colket

2011-01-01

56

ADVANCED HYBRID PARTICULATE COLLECTOR  

SciTech Connect

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses. The AHPC is currently being tested at the 2.7-MW scale at the Big Stone power station.

Stanley Miller; Rich Gebert; William Swanson

1999-11-01

57

Void/particulate detector  

DOEpatents

Voids and particulates are detected in a flowing stream of fluid contained in a pipe by a detector which includes three transducers spaced about the pipe. A first transducer at a first location on the pipe transmits an ultrasonic signal into the stream. A second transducer detects the through-transmission of the signal at a second location and a third transducer at a third location upstream from the first location detects the back-scattering of the signal from any voids or particulates. To differentiate between voids and particulates a fourth transducer is positioned at a fourth location which is also upstream from the first location. The back-scattered signals are normalized with the through-transmission signal to minimize temperature fluctuations.

Claytor, Thomas N. (Woodridge, IL); Karplus, Henry B. (Hinsdale, IL)

1985-01-01

58

Void/particulate detector  

SciTech Connect

Voids and particulates are detected in a flowing stream of fluid contained in a pipe by a detector which includes three transducdrs spaced about the pipe. A first transducer at a first location on the pipe transmits an ultrasonic signal into the stream. A second transducer detects the through-transmission of the signal at a second location and a third transducer at a third location upstream from the first location detects the back-scattering of the signal from any voids or particulates. To differentiate between voids and particulates a fourth transducer is positioned at a fourth location which is also upstream from the first location. The back-scattered signals are normalized with the through-transmission signal to minimize temperature fluctuations.

Clayton, T. N.; Karplus, H. B.

1985-09-24

59

Particulate Measurement - Motorcycle Test Results.  

National Technical Information Service (NTIS)

Particulate testing has been successfully completed on two different two-stroke powered motorcycles. The results indicate that the amount of particulate material produced by motorcycles is no greater than that from light-duty diesel automobiles. This conc...

E. Danielson

1978-01-01

60

PARTICULATE MATTER SUPERSITES PROGRAM  

EPA Science Inventory

Background: In promulgating the new PM2.5 NAAQS (July 1997), Congress recognized scientific uncertainties associated with fine particulate matter to include composition, source-receptor relationships, and health and exposure effects. As a result, Congress provided EPA with dire...

61

Analysis of microsize particulates  

NASA Technical Reports Server (NTRS)

Unique methods for analyzing individual particles ranging in size from 0.01 to 1000 micrometers have been developed for investigation of nature of cosmic dust. Methods are applicable to particulate aerosols and contaminants characteristically encountered in studies of air pollution and in experiments designed to abate pollution.

Blanchard, M. B.; Farlow, N. H.; Ferry, G. V.

1972-01-01

62

Void/Particulate Detector.  

National Technical Information Service (NTIS)

Apparatus for detecting voids and particulates in a flowing stream of fluid contained in a pipe may comprise: (a) a transducer for transmitting an ultrasonic signal into the stream, coupled to the pipe at a first location; (b) a second transducer for dete...

T. N. Claytor H. B. Karplus

1983-01-01

63

Health Effects of Particulate Matter  

NSDL National Science Digital Library

This EPA site gives a brief overview of how different sized particulate matter affects human health. It also discusses the environmental impacts of particulate matter, including haze and acid rain. The site also provides links to more in-depth resources about particle pollution and air quality criteria for particulate matter.

Agency, Environmental P.

64

Rigid particulate matter sensor  

DOEpatents

A sensor to detect particulate matter. The sensor includes a first rigid tube, a second rigid tube, a detection surface electrode, and a bias surface electrode. The second rigid tube is mounted substantially parallel to the first rigid tube. The detection surface electrode is disposed on an outer surface of the first rigid tube. The detection surface electrode is disposed to face the second rigid tube. The bias surface electrode is disposed on an outer surface of the second rigid tube. The bias surface electrode is disposed to face the detection surface electrode on the first rigid tube. An air gap exists between the detection surface electrode and the bias surface electrode to allow particulate matter within an exhaust stream to flow between the detection and bias surface electrodes.

Hall, Matthew (Austin, TX) [Austin, TX

2011-02-22

65

Void/particulate detector  

DOEpatents

Apparatus for detecting voids and particulates in a flowing stream of fluid contained in a pipe may comprise: (a) a transducer for transmitting an ultrasonic signal into the stream, coupled to the pipe at a first location; (b) a second transducer for detecting the through-transmission of said signal, coupled to the pipe at a second location; (c) a third transducer for detecting the back-scattering of said signal, coupled to the pipe at a third location, said third location being upstream from said first location; (d) circuit means for normalizing the back-scattered signal from said third transducer to the through-transmitted signal from said second transducer; which normalized signal provides a measure of the voids and particulates flowing past said first location.

Claytor, T.N.; Karplus, H.B.

1983-09-26

66

Regenerable particulate filter  

DOEpatents

A method of making a three-dimensional lattice structure, such as a filter used to remove particulates from a gas stream, where the physical lattice structure is designed utilizing software simulation from pre-defined mass transfer and flow characteristics and the designed lattice structure is fabricated using a free-form fabrication manufacturing technique, where the periodic lattice structure is comprised of individual geometric elements.

Stuecker, John N. (Albuquerque, NM); Cesarano, III, Joseph (Albuquerque, NM); Miller, James E. (Albuquerque, NM)

2009-05-05

67

ADVANCED HYBRID PARTICULATE COLLECTOR  

SciTech Connect

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and recollection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham

2000-12-01

68

42 CFR 84.125 - Particulate tests; canisters containing particulate filters; minimum requirements.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Particulate tests; canisters containing particulate filters... Gas Masks § 84.125 Particulate tests; canisters containing particulate filters...183, except for the airflow resistance test of §...

2012-10-01

69

Adenosine and Gastrointestinal Inflammation  

PubMed Central

Nucelosides such as adenosine (Ado) influence nearly every aspect of physiology and pathophysiology. Extracellular nucleotides liberated at local sites of inflammation are metabolized through regulated phosphohydrolysis by a series of ecto-nucleotidases including ectonucleoside triphosphate diphosphohydrolase-1 (CD39) and ecto-5?-nucleotidase (CD73), found on the surface of a variety of cell types. Once generated, Ado is made available to bind and activate one of four G-protein-coupled Ado receptors. Recent in vitro and in vivo studies implicate Ado in a broad array of tissue protective mechanisms that provide new insight into adenosine actions. Studies in cultured cells and murine tissues have indicated that Ado receptors couple to novel post-translational protein modifications, including Cullin deneddylation, as a new anti-inflammatory mechanism. Studies in Ado receptor-null mice have been revealing and indicate a particularly important role for the Ado A2B receptor in animal models of intestinal inflammation. Here, we review contributions of Ado to cell and tissue stress responses, with a particular emphasis on the gastrointestinal mucosa.

Colgan, Sean P.; Fennimore, Blair; Ehrentraut, Stefan F.

2013-01-01

70

Numerical model of particulate transport.  

National Technical Information Service (NTIS)

The transport of particulate matter occurs in a variety of physical systems. We describe a statistical model of particulate transport that can be used to simulate these systems. The physical particles are represented by a set of computational packets of p...

L. D. Cloutman

1991-01-01

71

Particulate erosion mechanisms  

NASA Technical Reports Server (NTRS)

Particulate damage and erosion of ductile metals are today plaguing design and field engineers in diverse fields of engineering and technology. It was found that too many models and theories were proposed leading to much speculation from debris analysis and failure mechanism postulations. Most theories of solid particle erosion are based on material removal models which do not fully represent the actual physical processes of material removal. The various mechanisms proposed thus far are: melting, low-cycle fatigue, extrusion, delamination, shear localization, adhesive material transfer, etc. The experimental data on different materials highlighting the observed failure modes of the deformation and cutting wear processes using optical and scanning electron microscopy are presented. The most important mechanisms proved from the experimental observations of the specimens exposed to both spherical and angular particles are addressed, and the validity of the earlier theories discussed. Both the initial stages of damage and advanced stages of erosion were studied to gain a fundamental understanding of the process.

Veerabhadrarao, P.; Buckley, D. H.

1983-01-01

72

Magnetic characterization of airborne particulates  

NASA Astrophysics Data System (ADS)

Burning fossil fuels from vehicles, domestics, industries and power plants in the large urban or industrial areas emit significant quantity of anthropogenic particulates which become a potential threat to human health. Here, we present temporal variability of particulate pollution associated with compositional differences, using magnetic measurements and electron microscopic observations. Six different grain-sizes of airborne particulates have been collected by filtering from 10 precipitation events in Seoul, Korea from February 2009 to June 2009. Magnetic concentration proxies show relatively better (R2 >0.6) and poorer correlations (R2 <0.3) with the masses of samples filtered by >0.45 ?m and <0.45 ?m sizes, respectively, suggesting the usefulness of magnetic characterization for the >0.45 ?m particulates. Temporally, magnetic concentrations are higher in the cold season than the warm season. In particular, a significant increase of magnetic concentration is observed in 3 ?m and 1 ?m filters after the Chinese wind-blown dust events, indicating additional influx of fine-grained anthropogenic particulates into Seoul. Microscopic observations identify that increase of magnetic concentration is highly linked with the frequent occurrence of combustion derived particulates (i.e., carbon and/or sulfur mixed particles) than natural alumino-silicates. Overall, the present study demonstrates that magnetic measurements efficiently reflect the concentration of particulates produced from fossil-fuel combustion among the airborne particles from various sources.

Kim, W.; Doh, S.; Yu, Y.

2010-12-01

73

Micromechanics for particulate reinforced composites  

NASA Technical Reports Server (NTRS)

A set of micromechanics equations for the analysis of particulate reinforced composites is developed using the mechanics of materials approach. Simplified equations are used to compute homogenized or equivalent thermal and mechanical properties of particulate reinforced composites in terms of the properties of the constituent materials. The microstress equations are also presented here to decompose the applied stresses on the overall composite to the microstresses in the constituent materials. The properties of a 'generic' particulate composite as well as those of a particle reinforced metal matrix composite are predicted and compared with other theories as well as some experimental data. The micromechanics predictions are in excellent agreement with the measured values.

Murthy, Pappu L. N.; Goldberg, Robert K.; Mital, Subodh K.

1996-01-01

74

ADVANCED HYBRID PARTICULATE COLLECTOR  

SciTech Connect

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be caused by electrical effects. Subsequently, extensive theoretical, bench-scale, and pilot-scale investigations were completed to find an approach to prevent bag damage without compromising AHPC performance. Results showed that the best bag protection and AHPC performance were achieved by using a perforated plate installed between the discharge electrodes and bags. This perforated-plate design was then installed in the 2.5-MW AHPC at Big Stone Power Plant in Big Stone City, South Dakota, and the AHPC was operated from March to June 2001. Results showed that the perforated-plate design solved the bag damage problem and offered even better AHPC performance than the previous design. All of the AHPC performance goals were met, including ultrahigh collection efficiency, high air-to-cloth ratio, reasonable pressure drop, and long bag-cleaning interval.

Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

2001-12-01

75

Electrically heated particulate filter restart strategy  

DOEpatents

A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-07-12

76

High Pressure Particulate Physics Facility.  

National Technical Information Service (NTIS)

This report documents the initial development of the High Pressure Particulate Physics (HP3) facility. The facility is anticipated to allow precision impact of two flat plates at a very high degree of precision with minimal misalignment when completed. A ...

L. C. Chhabildas W. L. Cooper W. R. Maines

2011-01-01

77

Electrical diesel particulate filter (DPF) regeneration  

DOEpatents

An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

Gonze, Eugene V; Ament, Frank

2013-12-31

78

Hydrocarbon-enhanced particulate filter regeneration via microwave ignition  

DOEpatents

A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.

Gonze, Eugene V. (Pinckney, MI); Brown, David B. (Brighton, MI)

2010-02-02

79

Atmospheric Particulate Measurements in Norfolk, Virginia.  

National Technical Information Service (NTIS)

Characterization of atmospheric particulates was conducted at a site near the center of Norfolk, Virginia. Air quality was measured in terms of atmospheric mass loading, particle size distribution, and particulate elemental composition for a period of 2 w...

R. W. Storey R. J. Sentell D. C. Woods J. R. Smith F. S. Harris

1975-01-01

80

NONFERROUS INDUSTRY PARTICULATE EMISSIONS: SOURCE CATEGORY REPORT  

EPA Science Inventory

The report gives results of the development of particulate emission factors based on cutoff size for inhalable particles for the nonferrous industry. After a review of available information characterizing particulate emissions from nonferrous plants, the data were summarized and ...

81

PARTICULATE EMISSION MEASUREMENTS FROM CONTROLLED CONSTRUCTION ACTIVITIES  

EPA Science Inventory

The report summarized the results of field testing of the effectiveness of control measures for sources of fugitive particulate emissions found at construction sites. The effectiveness of watering temporary, unpaved travel surfaces on emissions of particulate matter with aerodyna...

82

Method for dispersing catalyst onto particulate material.  

National Technical Information Service (NTIS)

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal s...

B. R. Utz A. V. Cugini

1990-01-01

83

PAVED ROAD PARTICULATE EMISSIONS: SOURCE CATEGORY REPORT  

EPA Science Inventory

The report gives results of extensive field tests to develop emission factors for particulate emissions generated by traffic entrainment of paved road surface particulate matter. Using roadway surface silt loading as the basis, predictive emission factor equations for each partic...

84

Process for particulate removal from coal liquids  

DOEpatents

Suspended solid particulates are removed from liquefied coal products by first subjecting such products to hydroclone action for removal in the underflow of the larger size particulates, and then subjecting the overflow from said hydroclone action, comprising the residual finer particulates, to an electrostatic field in an electrofilter wherein such finer particulates are deposited in the bed of beads of dielectric material on said filter. The beads are periodically cleaned by backwashing to remove the accumulated solids.

Rappe, Gerald C. (Macungie, PA)

1983-01-01

85

Solid particulate aerosol fire suppressants  

Microsoft Academic Search

A variety of private and public sector programs are developing a new class of fire suppressants, known generically as solid particulate aerosols. These have superior volumetric efficiency, low initial and life-cycle costs, low toxicity, no known global atmospheric environmental impacts (ODP\\/GWP), and the potential for a wide variety of applications. Researchers are developing solid compound formulations that, when pyrotechnically initiated,

Charles J. Kibert; Douglas Dierdorf

1994-01-01

86

MODELING PARTICULATE CHARGING IN ESPS  

EPA Science Inventory

In electrostatic precipitators there is a strong interaction between the particulate space charge and the operating voltage and current of an electrical section. Calculating either the space charge or the operating point when the other is fixed is not difficult, but calculating b...

87

Monitoring of particulate matter outdoors  

Microsoft Academic Search

Recent studies of the size and composition of atmospheric particulate matter (PM) have demonstrated the usefulness of separating atmospheric PM into its fine and coarse components. The need to measure the mass and composition of fine and coarse PM separately has been emphasized by research in exposure, epidemiology, and toxicology of atmospheric PM. This paper provides a background on the

W. E. Wilson; Judith C. Chow; Candis Claiborn; Wei Fusheng; Johann Engelbrecht; John G. Watson

2002-01-01

88

MONITORING OF PARTICULATE MATTER OUTDOORS  

EPA Science Inventory

Recent studies of the size and composition of atmospheric particulate matter (PM) have demonstrated the usefulness of separating atmospheric PM into its fine and coarse components. The need to measure the mass and composition of fine and coarse PM separately has been emphasized b...

89

Ecological effects of particulate matter  

Microsoft Academic Search

Atmospheric particulate matter (PM) is a heterogeneous material. Though regulated as un-speciated mass, it exerts most effects on vegetation and ecosystems by virtue of the mass loading of its chemical constituents. As this varies temporally and spatially, prediction of regional impacts remains difficult. Deposition of PM to vegetated surfaces depends on the size distribution of the particles and, to a

D. A Grantz; J. H. B Garner; D. W Johnson

2003-01-01

90

Polarization signatures of airborne particulates  

NASA Astrophysics Data System (ADS)

Exploratory research has been conducted with the aim of completely determining the polarization signatures of selected particulates as a function of wavelength. This may lead to a better understanding of the interaction between electromagnetic radiation and such materials, perhaps leading to the point detection of bio-aerosols present in the atmosphere. To this end, a polarimeter capable of measuring the complete Mueller matrix of highly scattering samples in transmission and reflection (with good spectral resolution from 300 to 1100 nm) has been developed. The polarization properties of Bacillus subtilis (surrogate for anthrax spore) are compared to ambient particulate matter species such as pollen, dust, and soot. Differentiating features in the polarization signatures of these samples have been identified, thus demonstrating the potential applicability of this technique for the detection of bio-aerosol in the ambient atmosphere.

Raman, Prashant; Fuller, Kirk A.; Gregory, Don A.

2013-07-01

91

Quasicrystalline particulate reinforced aluminum composite  

SciTech Connect

Particulate reinforced aluminum and aluminum alloy composites are rapidly emerging as new commercial materials for aerospace, automotive, electronic packaging and other high performance applications. However, their low processing ductility and difficulty in recyclability have been the key concern. In this study, two composite systems having the same aluminum alloy matrix, one reinforced with quasicrystals and the other reinforced with the conventional SiC reinforcements were produced with identical processing routes. Their processing characteristics and tensile mechanical properties were compared.

Anderson, I.E.; Biner, S.B.; Sordelet, D.J.; Unal, O.

1997-07-01

92

SOUTHERN FINE PARTICULATE MONITORING PROJECT  

SciTech Connect

This is the second quarterly progress report of the ''Southern Fine Particulate Monitoring Project'', funded by the U.S. Department of Energy's National Energy Technology Laboratory under DOE Cooperative Agreement No. DE-FC26-00NT40770 to Southern Research Institute (SRI). In this two year project SRI will conduct detailed studies of ambient fine particulate matter in the Birmingham, AL metropolitan area. Project objectives include: Augment existing measurements of primary and secondary aerosols at an established urban southeastern monitoring site; Make a detailed database of near-continuous measurements of the time variation of fine particulate mass, composition, and key properties (including particle size distribution); Apply the measurements to source attribution, time/transport properties of fine PM, and implications for management strategies for PM{sub 2.5}; and Validate and compare key measurement methods used in this study for applicability within other PM{sub 2.5} research by DOE-FE, EPA, NARSTO, and others.

Ashley D. Williamson

2001-04-01

93

Enlèvement de particules par laser impulsionnel  

NASA Astrophysics Data System (ADS)

L'enlèvement de particules par laser impulsionnel (ns) est étudié expérimentalement. Des efficacités supérieures à 90% sont obtenues pour l'enlèvement de particules de polystyrene (PS) de diamètre 385 nm sur des surfaces de Si et Cu. Les fluences seuils d'enlèvement sont déterminées et comparées à une modélisation de l'expansion thermique du substrat. L'interprétation est discutée en terme de mécanismes fondamentaux envisageables responsables de l'éjection des particules.

Grojo, D.; Delaporte, P.; Cros, A.

2005-06-01

94

Zone heated diesel particulate filter electrical connection  

DOEpatents

An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

Gonze, Eugene V. (Pinckney, MI); Paratore, Jr., Michael J. (Howell, MI)

2010-03-30

95

Diesel particulate filter with zoned resistive heater  

DOEpatents

A diesel particulate filter assembly comprises a diesel particulate filter (DPF) and a heater assembly. The DPF filters a particulate from exhaust produced by an engine. The heater assembly has a first metallic layer that is applied to the DPF, a resistive layer that is applied to the first metallic layer, and a second metallic layer that is applied to the resistive layer. The second metallic layer is etched to form a plurality of zones.

Gonze, Eugene V [Pinckney, MI

2011-03-08

96

DEVELOPMENT OF COMPUTER MODULES OF PARTICULATE PROCESSES FOR REGIONAL PARTICULATE MODEL  

EPA Science Inventory

The development of an aerosol model for inclusion in the EPA Regional Particulate Model is described. Existing computer modules of particulate processes developed under EPA contract by Professors Brock, Seinfeld, and Whitby are compared to determine efficient and accurate methods...

97

Particulate Air Pollution and Morbidity in the California Central Valley: A High Particulate Pollution Region.  

National Technical Information Service (NTIS)

The purpose of this study was to evaluate the relationship between particulate air pollution and morbidity among the Kaiser Permanente (KP) membership who reside in the Central Valley (CV) of California. Daily augmented particulate matter (PM) monitoring ...

S. K. Van Den Eeden C. P. Quesenberry J. Shan F. Lurmann

2002-01-01

98

Electrically heated particulate filter using catalyst striping  

DOEpatents

An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating is applied to the PF that increases a temperature of the combustion of the particulates within the PF.

Gonze, Eugene V; Paratore, Jr., Michael J; Ament, Frank

2013-07-16

99

Methods of separating particulate residue streams  

DOEpatents

A particulate residue separator and a method for separating a particulate residue stream may include an air plenum borne by a harvesting device, and have a first, intake end and a second, exhaust end; first and second particulate residue air streams that are formed by the harvesting device and that travel, at least in part, along the air plenum and in a direction of the second, exhaust end; and a baffle assembly that is located in partially occluding relation relative to the air plenum and that substantially separates the first and second particulate residue air streams.

Hoskinson, Reed L. (Rigby, ID); Kenney, Kevin L. (Idaho Falls, ID); Wright, Christopher T. (Idaho Falls, ID); Hess, J. Richard (Idaho Falls, ID)

2011-04-05

100

Powder and particulate production of metallic alloys  

NASA Technical Reports Server (NTRS)

Developments of particulate metallurgy of alloyed materials where the final products is a fully dense body are discussed. Particulates are defined as powders, flakes, foils, silvers, ribbons and strip. Because rapid solidification is an important factor in particulate metallurgy, all of the particulates must have at least one dimension which is very fine, sometimes as fine as 10 to 50 microns, but move typically up to several hundred microns, provided that the dimension permits a minimum solidification rate of at least 100 K/s.

Grant, N. J.

1982-01-01

101

Combustor for fine particulate coal  

DOEpatents

A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

Carlson, L.W.

1988-01-26

102

Combustor for fine particulate coal  

DOEpatents

A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

Carlson, L.W.

1988-11-08

103

Measuring Particulate Emissions from Autos  

NSDL National Science Digital Library

This learning activity from the Advanced Technology Environmental and Energy Center (ATEEC) is intended to help environmental science or biology students connect a real-world problem to the application of math, science, technical and critical thinking knowledge and skill concepts; the lesson specifically focuses on particulate emissions from automobiles and their impact on air pollution. The activity should take about one class period to complete (plus time for students to complete analysis outside of class), and requires a few easily obtainable materials. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Willey, Babe

2011-03-10

104

Combustor for fine particulate coal  

DOEpatents

A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover.

Carlson, Larry W. (Oswego, IL)

1988-01-01

105

Positive artifact in the measurement of particulate carbonaceous substances using an ambient carbon particulate monitor  

Microsoft Academic Search

An ambient carbon particulate monitor (ACPM), which is a commercially available instrument for automatic continuous measurement of particulate carbon, has been used in the recent studies. In order to investigate the amount of the positive artifact in the measurement of particulate carbonaceous substances by the ACPM, field duplicate experiments using two ACPMs and a parallel plate organic denuder were conducted

Kiyoshi Matsumoto; Teruaki Hayano; Mitsuo Uematsu

2003-01-01

106

Airborne particulate matter in spacecraft  

NASA Technical Reports Server (NTRS)

Acceptability limits and sampling and monitoring strategies for airborne particles in spacecraft were considered. Based on instances of eye and respiratory tract irritation reported by Shuttle flight crews, the following acceptability limits for airborne particles were recommended: for flights of 1 week or less duration (1 mg/cu m for particles less than 10 microns in aerodynamic diameter (AD) plus 1 mg/cu m for particles 10 to 100 microns in AD); and for flights greater than 1 week and up to 6 months in duration (0.2 mg/cu m for particles less than 10 microns in AD plus 0.2 mg/cu m for particles 10 to 100 microns in AD. These numerical limits were recommended to aid in spacecraft atmosphere design which should aim at particulate levels that are a low as reasonably achievable. Sampling of spacecraft atmospheres for particles should include size-fractionated samples of 0 to 10, 10 to 100, and greater than 100 micron particles for mass concentration measurement and elementary chemical analysis by nondestructive analysis techniques. Morphological and chemical analyses of single particles should also be made to aid in identifying airborne particulate sources. Air cleaning systems based on inertial collection principles and fine particle collection devices based on electrostatic precipitation and filtration should be considered for incorporation into spacecraft air circulation systems. It was also recommended that research be carried out in space in the areas of health effects and particle characterization.

1988-01-01

107

Southern Fine Particulate Monitoring Project  

SciTech Connect

This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.

Ashley Williamson

2003-05-31

108

40 CFR 52.275 - Particulate matter control.  

Code of Federal Regulations, 2010 CFR

...because they control emissions of particulate matter, and because there...the national standards for particulate matter: (1) Lake County...they relax the control on particulate matter emissions without...retained and shall remain in effect for Federal enforcement...

2010-07-01

109

40 CFR 52.275 - Particulate matter control.  

Code of Federal Regulations, 2010 CFR

...because they control emissions of particulate matter, and because there...the national standards for particulate matter: (1) Lake County...they relax the control on particulate matter emissions without...retained and shall remain in effect for Federal enforcement...

2009-07-01

110

Airborne Particulates in the OR Environment  

Microsoft Academic Search

Intraoperative sampling of airborne particulates is rarely performed in teh OR environment because of technical difficulties associated with sampling methodologies and because of the common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). In this study, investigators recovered nonviable (ie, lint) and viable (ie, microorganisms) particulates during vascular surgery using a personal cascade impactor sampling device.

Charles E. Edmiston; Sharon Sinski; Gary R. Seabrook; Dorna Simons; Michael P. Goheen

1999-01-01

111

Air Quality Criteria for Particulate Matter.  

ERIC Educational Resources Information Center

To assist states in developing air quality standards, this book offers a review of literature related to atmospheric particulates and the development of criteria for air quality. It not only summarizes the current scientific knowledge of particulate air pollution, but points up the major deficiencies in that knowledge and the need for further…

National Air Pollution Control Administration (DHEW), Washington, DC.

112

Testing Students' Use of the Particulate Theory  

ERIC Educational Resources Information Center

High School students' understanding about the particulate theory of matter and their use of particulate terminology is investigated. The Physical Changes Concepts Test (PCCT) was administered in two forms, an applied version and a theoretical version, to determine whether students scientifically understood the concepts well enough to apply them to…

Williamson, Vickie; Huffman, Jason; Peck, Larry

2004-01-01

113

Understanding the Particulate Nature of Matter.  

ERIC Educational Resources Information Center

Cites studies related to students' misconceptions about the particulate nature of matter. Stresses that a good understanding of these concepts is fundamental to the study of chemistry itself. Reports on a study of preservice elementary teachers views of the particulate nature of matter before instruction on the topic. (TW)

Gabel, Dorothy L.; And Others

1987-01-01

114

Advanced particulate matter control apparatus and methods  

DOEpatents

Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.

Miller, Stanley J. (Grand Forks, ND); Zhuang, Ye (Grand Forks, ND); Almlie, Jay C. (East Grand Forks, MN)

2012-01-10

115

Latex allergen in respirable particulate air pollution  

Microsoft Academic Search

Objective: Urban air samples contain numerous irregular respirable black particles, which may be airborne tire fragments. A major component of tires is natural latex. Proteins of natural latex can act as adjuvants and as antigens capable of eliciting immediate hypersensitivity, making their presence in particulate air pollution an important clinical issue. Methods: Particulate air pollutants were collected by volumetric sampling

P. Brock Williams; Martin P. Buhr; Richard W. Weber; Micheal A. Volz; Jerald W. Koepke; John C. Selner

1995-01-01

116

Triboelectric technology for particulate emission measurement  

SciTech Connect

The author discusses how triboelectric technology (monitoring of particulate emission by sensing impacting particle charge transfer) has enabled a new generation of particulate emission detectors to be developed. They are providing to be much more suitable than traditional opacity methods. The reason for this is that they require little or no maintenance.

Averdieck, W.J. (Auburn International, Inc., Danvers, MA (USA))

1987-01-01

117

Global developments in diesel particulate control  

SciTech Connect

This book contains the following subject titles: Diesel particulate control around the world; Electric heating regeneration of large wall-flow type DPF; On-line measurement of diesel particle loading in ceramic filters; Evaluation of a self-cleaning particulate control system for diesel engines.

Not Available

1991-01-01

118

Electrically heated particulate filter propagation support methods and systems  

DOEpatents

A control system that controls regeneration of a particulate filter is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate combustion of particulate matter in the particulate filter. A propagation module estimates a propagation status of the combustion of the particulate matter based on a combustion temperature. A temperature adjustment module controls the combustion temperature by selectively increasing a temperature of exhaust that passes through the particulate filter.

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-06-07

119

Hypocoordinated solids in particulate media  

NASA Astrophysics Data System (ADS)

We propose a "phase diagram" for particulate systems with purely repulsive contact forces, such as granular media and colloids. We characterize two classes of behavior as a function of the input kinetic energy per degree of freedom T0 and packing fraction deviation from jamming onset ?? =?-?J using simulations of frictionless disks. Isocoordinated solids (ICS) exist above jamming; they possess an average contact number equal to the isostatic value ziso. ICS display "strict" harmonic response, where the density of vibrational modes from the Fourier transform of the velocity autocorrelation function is a set of sharp peaks at eigenfrequencies ?kd of the dynamical matrix. In contrast, hypocoordinated solids (HCS) occur above and below jamming and possess fluctuating networks of interparticle contacts but do not undergo cage-breaking particle rearrangements. The density of vibrational frequencies for the HCS is not a collection of sharp peaks at ?kd, but it does possess a common form over a range of ?? and T0.

Bertrand, Thibault; Schreck, Carl F.; O'Hern, Corey S.; Shattuck, Mark D.

2014-06-01

120

Radiant zone heated particulate filter  

DOEpatents

A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

Gonze, Eugene V [Pinckney, MI

2011-12-27

121

Influence of Ecto-Nucleoside Triphosphate Diphosphohydrolase Activity on Trypanosoma cruzi Infectivity and Virulence  

PubMed Central

Background The protozoan Trypanosoma cruzi is the causative agent of Chagas disease. There are no vaccines or effective treatment, especially in the chronic phase when most patients are diagnosed. There is a clear necessity to develop new drugs and strategies for the control and treatment of Chagas disease. Recent papers have suggested the ecto-nucleotidases (from CD39 family) from pathogenic agents as important virulence factors. In this study we evaluated the influence of Ecto-Nucleoside-Triphosphate-Diphosphohydrolase (Ecto-NTPDase) activity on infectivity and virulence of T. cruzi using both in vivo and in vitro models. Methodology/Principal Findings We followed Ecto-NTPDase activities of Y strain infective forms (trypomastigotes) obtained during sequential sub-cultivation in mammalian cells. ATPase/ADPase activity ratios of cell-derived trypomastigotes decreased 3- to 6-fold and infectivity was substantially reduced during sequential sub-cultivation. Surprisingly, at third to fourth passages most of the cell-derived trypomastigotes could not penetrate mammalian cells and had differentiated into amastigote-like parasites that exhibited 3- to 4-fold lower levels of Ecto-NTPDase activities. To evidence the participation of T. cruzi Ecto-NTPDase1 in the infective process, we evaluated the effect of known Ecto-ATPDase inhibitors (ARL 67156, Gadolinium and Suramin), or anti-NTPDase-1 polyclonal antiserum on ATPase and ADPase hydrolytic activities in recombinant T. cruzi NTPDase-1 and in live trypomastigotes. All tests showed a partial inhibition of Ecto-ATPDase activities and a marked inhibition of trypomastigotes infectivity. Mice infections with Ecto-NTPDase-inhibited trypomastigotes produced lower levels of parasitemia and higher host survival than with non-inhibited control parasites. Conclusions/Significance Our results suggest that Ecto-ATPDases act as facilitators of infection and virulence in vitro and in vivo and emerge as target candidates in chemotherapy of Chagas disease.

Santos, Ramon F.; Possa, Marcela A. S.; Bastos, Matheus S.; Guedes, Paulo M. M.; Almeida, Marcia R.; DeMarco, Ricardo; Verjovski-Almeida, Sergio; Bahia, Maria T.; Fietto, Juliana L. R.

2009-01-01

122

Design improvement on diesel particulate bag filters  

SciTech Connect

In order to improve the compactness and simplify the structure of diesel particulate bag filter, a preliminary design and test of an envelope bag filter were carried out, and the results confirmed that it is impractical to adopt envelope bag in diesel particulate bag filter design. Therefore, another double-layer tube bag filter was developed which has a compact and simple structure. The filter was tested on a 485Q diesel engine dynamometer bench, and the results showed that it worked reliably with particulate collection efficiency more than 90% and its effect on diesel economy no more than 1%. 5 refs., 9 figs.

Xiao, F. [Tianjin Univ. (China); Liu, X.

1994-09-01

123

Macrophage-mediated endothelial inflammatory responses to airborne particulates: impact of particulate physicochemical properties.  

PubMed

Epidemiological studies have implicated a role for airborne particulates of <2.5 microm diameter in the development/exacerbation of chronic cardiopulmonary disease; however, specific pathogenic mechanisms and the etiological significance of particle physicochemical properties remain unresolved. Using a microporous aluminosilicate zeolite Y as a manifold, we have synthesized 1 microm particulates of pure carbon (C), carbon-iron (C/Fe), and carbon-iron/fluoro-aluminum silicate (C-Fe/F-Al-Si). We have used these particulates, as well as coal fly ash (CFA) and diesel exhaust particulates (DEP), to test the hypotheses that human macrophages treated with particulates elaborate proinflammatory cytokines in quantities sufficient to induce endothelial adhesion molecule expression and that macrophage responses to particulate exposure vary as a function of particulate physicochemical properties. Human monocyte-derived macrophages (Mø) were exposed for 24 h to sublethal concentrations of particulates, at which time phagocytosis was evident from optical microscopy. Human arterial, microvascular, or venous endothelial cells (EC) were treated with clarified supernatants recovered from Mø cultures, stained with fluorescein-conjugated mononclonal antibodies specific for endothelial adhesion molecules intercellular adhesion molecule-1, vascular cell adhesion molecule-1, or E-selectin, and assayed by fluorescence flow cytometry. Data generated by these experiments demonstrate that while supernatants of Mø exposed to CFA and C particulates are relatively ineffective, supernatants from DEP, C/Fe, or C-Fe/F-Al-Si strongly induced adhesion molecule expression on EC, responses which were completely attenuated by antibody with blocking specificity for tumor necrosis factor alpha. Because the only difference between C and C/Fe particulates is the presence of surface iron on C/Fe, these findings suggest particulate-induced oxidative stress as a contributing factor in Mø activation and implicate redox active iron as a major determinant of particulate bioreactivity. PMID:15487890

Kristovich, Robert; Knight, Deborah A; Long, John F; Williams, Marshall V; Dutta, Prabir K; Waldman, W James

2004-10-01

124

Differential Spectroscopic Imaging of Particulate Explosives Residue  

SciTech Connect

We present experimental results showing transmission and reflection imaging of approximately 100 microgram quantities of particulate explosives residue using a commercial uncooled microbolometer infrared camera and CO2 laser differential wavelength illumination.

Bernacki, Bruce E.; Ho, Nicolas

2008-04-01

125

Modelling airborne dispersion of coarse particulate material.  

National Technical Information Service (NTIS)

Methods of modelling the airborne dispersion and deposition of coarse particulates are presented, with the emphasis on the heavy particles identified as possible constituents of releases from damaged AGR fuel. The first part of this report establishes the...

D. D. Apsley

1989-01-01

126

Evaluations of Novel Particulate Control Devices.  

National Technical Information Service (NTIS)

The report gives results of fractional and overall mass efficiency tests of four novel particulate control devices. Three were wet scrubbers: an Aronetics (Chemico) Two-Phase Jet Scrubber, an Entoleter Centrifield Scrubber, and a CEA Variable-Throat Ventu...

J. D. McCain

1978-01-01

127

Evaluation of the Particulate Additive Test.  

National Technical Information Service (NTIS)

The objective of this study is to acquire and/or develop commercially available equipment for conducting the Particulate Additive Test (PAT) and Laboratory Stability Test (LAST). Dr. Hussein Bahia and his coworkers developed these tests under the National...

J. Youtcheff A. Shenoy

2004-01-01

128

PARTICULATE DATA REDUCTION SYSTEM (PADRE) USER GUIDE  

EPA Science Inventory

The report, a user guide, describes the capabilities and use of the Particulate Data Reduction (PADRE) system, an interactive computer program that facilitates entry, reduction, and analysis of cascade impactor data for particle size distributions. Example sessions are provided t...

129

FILTER MEDIA FOR COLLECTING DIESEL PARTICULATE MATTER  

EPA Science Inventory

Certification of particulate emissions from diesel motor vehicles involves filtration of measured aliquots of the total air diluted exhaust. Seven commercially available filter media were examined for this purpose. The media included a variety of PTFE membrane filters, glass fibe...

130

Filter Media for Collecting Diesel Particulate Matter.  

National Technical Information Service (NTIS)

Certification of particulate emissions from diesel motor vehicles involves filtration of measured aliquots of the total air diluted exhaust. Seven commercially available filter media were examined for this purpose. The media included a variety of PTFE mem...

F. Black L. Doberstein

1981-01-01

131

Particulate matter, oxidative stress and neurotoxicity.  

EPA Science Inventory

Particulate matter (PM), a component of air pollution has been epidemiologically associated with sudden deaths, cardiovascular and respiratory illnesses. The effects are more pronounced in patients with pre-existing conditions such as asthma, diabetes or obstructive pulmonary dis...

132

GENERATION OF FUMES SIMULATING PARTICULATE AIR POLLUTANTS  

EPA Science Inventory

The report describes techniques developed for generating large quantities of reproducible, stable, inorganic, fine-particle aerosol fumes. These fumes simulated particulate air pollutants emitted from power generation, basic oxygen furnaces, electric arc furnaces, and zinc smelti...

133

Airborne Particulates over Southern Africa  

NASA Technical Reports Server (NTRS)

This map shows the abundance of airborne particulates, or aerosols, over Southern Africa during the period August 14 - September 29, 2000. Low particle concentrations are shown in shades of blue, and high concentrations in shades of red. The results were generated from MISR imagery acquired over this time period, and processed using MISR's automated software system. The approach for deriving aerosol amount makes use of the variation of scene brightness and contrast as a function of observation angle. Black areas over the land area correspond to places where a result was not obtained, for example, due to the presence of clouds.

Extensive burning of grass and shrubland for land management and agriculture comprises a principal source of these aerosols. Vegetation availability increases northward, hence the greater abundance of haze and smoke in Angola and southern Zaire. The lower aerosol abundance around Lesotho and southeastern South Africa is consistent with the higher terrain elevations near the Drakensberg Mountains.

MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

2001-01-01

134

SOUTHERN FINE PARTICULATE MONITORING PROJECT  

SciTech Connect

This quarterly report presents results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the January-March, 2002 study period. The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. Some instrumental issues were noted with the upgrade of the APS model 3320 are described in the report, as well as preliminary performance indications for the upgraded instrument. During the quarter preliminary data analysis and modeling studies were conducted to test the potential of the North Birmingham site data for source attribution analyses. Our initial assessment has continued to be optimistic in this regard due to the location of the site relative to several important classes of local and midrange emission sources. We anticipate that these analyses will provide good separations of the effects of major source classes and spatial source clusters, and will provide useful information relevant to PM{sub 2.5} implementation strategies.

Unknown

2002-04-01

135

The Particulate Air Pollution Controversy  

PubMed Central

Scientists, regulators, legislators, and segments of industry and the lay public are attempting to understand and respond to epidemiology findings of associations between measures of modern particulate air pollutants (PM) and adverse health outcomes in urban dwellers. The associations have been interpreted to imply that tens of thousands of Americans are killed annually by small daily increments in PM. These epidemiology studies and their interpretations have been challenged, although it is accepted that high concentrations of air pollutants have claimed many lives in the past. Although reproducible and statistically significant, the relative risks associated with modern PM are very small and confounded by many factors. Neither toxicology studies nor human clinical investigations have identified the components and/or characteristics of PM that might be causing the health-effect associations. Currently, a massive worldwide research effort is under way in an attempt to identify whom might be harmed and by what substances and mechanisms. Finding the answers is important, because control measures have the potential not only to be costly but also to limit the availability of goods and services that are important to public health.

Phalen, Robert F.

2004-01-01

136

Particulate matter in the Venus atmosphere  

NASA Technical Reports Server (NTRS)

The paper presents a summary of the data currently available (June 1984) describing the planet-enshrouding particulate matter in the Venus atmosphere. A description and discussion of the state of knowledge of the Venus clouds and hazes precedes the tables and plots. The tabular material includes a precis of upper haze and cloud-top properties, parameters for model-size distributions for particles and particulate layers, and columnar masses and mass loadings.

Ragent, B.; Esposito, L. W.; Tomasko, M. G.; Marov, M. IA.; Shari, V. P.

1985-01-01

137

Spectral variability of the particulate backscattering ratio  

NASA Astrophysics Data System (ADS)

The spectral dependency of the particulate backscattering ratio is relevant in the fields of ocean color inversion, light field modeling, and inferring particle properties from optical measurements. Aside from theoretical predictions for spherical, homogeneous particles, we have very limited knowledge of the actual in situ spectral variability of the particulate backscattering ratio. This work presents results from five research cruises that were conducted over a three-year period. Water column profiles of physical and optical properties were conducted across diverse aquatic environments that offered a wide range of particle populations. The main objective of this research was to examine the behavior of the spectral particulate backscattering ratio in situ, both in terms of its absolute magnitude and its variability across visible wavelengths, using over nine thousand 1-meter binned data points for each of five wavelengths of the spectral particulate backscattering ratio. Our analysis reveals no spectral dependence of the particulate backscattering ratio within our measurement certainty, and a geometric mean value of 0.013 for this dataset. This is lower than the commonly used value of 0.0183 from Petzold’s integrated volume scattering data. Within the first optical depth of the water column, the mean particulate backscattering ratio was 0.010.

Whitmire, A. L.; Boss, E.; Cowles, T. J.; Pegau, W. S.

2007-05-01

138

Distribution of particulate carbohydrate species in the Bay of Bengal  

Microsoft Academic Search

Suspended particulate matter (SPM) of surface seawaters was collected during December 2003 to October 2004 at 10 stations\\u000a in the Bay of Bengal, and analyzed for particulate organic carbon (POC), total particulate nitrogen (TPN), total particulate\\u000a carbohydrate (TPCHO) and total particulate uronic acids (TPURA). The concentrations of POC, TPCHO and TPURA varied from 4.80\\u000a to 29.12, 0.85 to 4.24, 0.09

Vishwas B. Khodse; Narayan B. Bhosle; V. V. Gopalkrishna

2009-01-01

139

Ecological effects of particulate matter.  

PubMed

Atmospheric particulate matter (PM) is a heterogeneous material. Though regulated as un-speciated mass, it exerts most effects on vegetation and ecosystems by virtue of the mass loading of its chemical constituents. As this varies temporally and spatially, prediction of regional impacts remains difficult. Deposition of PM to vegetated surfaces depends on the size distribution of the particles and, to a lesser extent, on the chemistry. However, chemical loading of an ecosystem may be determined by the size distribution as different constituents dominate different size fractions. Coating with dust may cause abrasion and radiative heating, and may reduce the photosynthetically active photon flux reaching the photosynthetic tissues. Acidic and alkaline materials may cause leaf surface injury while other materials may be taken up across the cuticle. A more likely route for metabolic uptake and impact on vegetation and ecosystems is through the rhizosphere. PM deposited directly to the soil can influence nutrient cycling, especially that of nitrogen, through its effects on the rhizosphere bacteria and fungi. Alkaline cation and aluminum availability are dependent upon the pH of the soil that may be altered dramatically by deposition of various classes of PM. A regional effect of PM on ecosystems is linked to climate change. Increased PM may reduce radiation interception by plant canopies and may reduce precipitation through a variety of physical effects. At the present time, evidence does not support large regional threats due to un-speciated PM, though site-specific and constituent-specific effects can be readily identified. Interactions of PM with other pollutants and with components of climate change remain important areas of research in assessment of challenges to ecosystem stability. PMID:12676209

Grantz, D A; Garner, J H B; Johnson, D W

2003-06-01

140

Advanced Hybrid Particulate Collector Project Management Plan  

SciTech Connect

As the consumption of energy increases, its impact on ambient air quality has become a significant concern. Recent studies indicate that fine particles from coal combustion cause health problems as well as atmospheric visibility impairment. These problems are further compounded by the concentration of hazardous trace elements such as mercury, cadmium, selenium, and arsenic in fine particles. Therefore, a current need exists to develop superior, but economical, methods to control emissions of fine particles. Since most of the toxic metals present in coal will be in particulate form, a high level of fine- particle collection appears to be the best method of overall air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and cannot be collected in particulate control devices. Therefore, this project will focus on developing technology not only to provide ultrahigh collection efficiency of particulate air toxic emissions, but also to capture vapor- phase trace metals such as mercury and selenium. Currently, the primary state-of-the-art technologies for particulate control are fabric filters (baghouses) and electrostatic precipitators (ESPs). However, they both have limitations that prevent them from achieving ultrahigh collection of fine particulate matter and vapor-phase trace metals. The objective of this project is to develop a highly reliable advanced hybrid particulate collector (AHPC) that can provide > 99.99 % particulate collection efficiency for all particle sizes between 0.01 and 50 14m, is applicable for use with all U.S. coals, and is cost-0443competitive with existing technologies. Phase I of the project is organized into three tasks: Task I - Project Management, Reporting, and Subcontract Consulting Task 2 - Modeling, Design, and Construction of 200-acfm AHPC Model Task 3 - Experimental Testing and Subcontract Consulting

Miller, S.J.

1995-11-01

141

Particulate characterization for PFBC filter systems  

SciTech Connect

Southern Research Institute is participating, as a subcontractor to Southern Company Services (SCS), in METC`s project to establish a Power Systems Development Facility at Wilsonville, Alabama. This plant will serve as a facility for the development and testing of advanced systems for coal-based power generation. An important part of the program will be to test and evaluate various kinds of particulate control devices and systems for operation at high temperatures and high pressures. The hot gas cleanup technology is a critical factor in achieving the highest levels of energy efficiency in the advanced power systems. In connection with evaluation of particulate control devices to be installed at this facility, SRI has the responsibility for developing methods and equipment to characterize the particulate material suspended in the hot gas streams. Our objectives are to design systems for sampling and monitoring particulate mass loadings and size distributions at appropriate locations in the plant and to develop methods for operating these systems. We will assist SCS in the preparation of test plans for the operation of the plant, and we will participate in carrying out the particulate measurements.

Pontius, D.H.

1993-09-01

142

Thermogravimetric analysis of diesel particulate matter  

NASA Astrophysics Data System (ADS)

The regulated level of diesel particulate mass for 2008 light-duty diesel on-road engines will be 0.005 g km-1 in Europe. Measurements by weighing and analysis of this low level of particulate mass based on chemical extraction are costly, time consuming and hazardous because of the use of organic solvents, potentially carcinogenic. An alternative to this analysis is proposed here: a thermal mass analyser that measures the volatile fraction (VOF) as well as the soot fraction of the particulate matter (PM) collected on a cleaned fibre glass filter. This paper evaluates this new thermal mass measurement (TGA) as a possible alternative to the conventional chemical extraction method, and presents the results obtained with both methods when testing a diesel engine fuelled with a reference diesel fuel (REF), a pure biodiesel fuel (B100) and two blends with 30% and 70% v/v biodiesel (B30 and B70, respectively).

Lapuerta, M.; Ballesteros, R.; Rodríguez-Fernández, J.

2007-03-01

143

Method for dispersing catalyst onto particulate material  

SciTech Connect

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal. 2 figs., 1 tab.

Utz, B.R.; Cugini, A.V.

1990-01-01

144

Method for dispersing catalyst onto particulate material  

DOEpatents

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)

1992-01-01

145

Method for dispersing catalyst onto particulate material  

SciTech Connect

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal. 2 figs., 1 tab.

Utz, B.R.; Cugini, A.V.

1990-12-31

146

Method for dispersing catalyst onto particulate material  

SciTech Connect

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal. 2 figs.

Utz, B.R.; Cugini, A.V.

1992-03-17

147

Pulse combustion drying apparatus for particulate materials  

SciTech Connect

This patent describes a pulse jet combustion apparatus for the drying of particulate material of the type having: a combustion chamber having an air entry end, an exhaust end and a common longitudinal axis therebetween, an air inlet conduit coaxially connected to the air entry and thereof, a primary exhaust gas conduit coaxially connected to the exhaust end thereof and, a tailpipe coaxially connected to the end of the exhaust gas conduit for directing the exhaust gases past a locus of particulate material introduction and to a dried particulate receiving chamber. The improvements described here comprise: primary fuel nozzles mounted at the air entry end of the combustion chamber downstream of the air inlet conduit and positioned to direct combustible fuel to a common location on the longitudinal axis of the combustion chamber spaced a predetermined distance from the air entry end thereof.

Gray, R.R.; Marguth, V.M.

1987-01-20

148

A numerical model of particulate transport  

SciTech Connect

The transport of particulate matter occurs in a variety of physical systems. We describe a statistical model of particulate transport that can be used to simulate these systems. The physical particles are represented by a set of computational packets of particles. The initial particle size, velocity, and location for each packet is chosen by randomly sampling size, velocity, and source region distributions. The dynamics of the individual packets are calculated in detail by integrating their equations of motion, including momentum and energy exchange with the fluid. Numerical examples are provided. 16 refs., 11 figs., 1 tab.

Cloutman, L.D.

1991-03-01

149

Particulate matter sensor with a heater  

SciTech Connect

An apparatus to detect particulate matter. The apparatus includes a sensor electrode, a shroud, and a heater. The electrode measures a chemical composition within an exhaust stream. The shroud surrounds at least a portion of the sensor electrode, exclusive of a distal end of the sensor electrode exposed to the exhaust stream. The shroud defines an air gap between the sensor electrode and the shroud and an opening toward the distal end of the sensor electrode. The heater is mounted relative to the sensor electrode. The heater burns off particulate matter in the air gap between the sensor electrode and the shroud.

Hall, Matthew (Austin, TX)

2011-08-16

150

Strategic Workplan for Particulate Matter Research: 2000 to 2004.  

National Technical Information Service (NTIS)

The Strategic Workplan for Particulate Matter: 2000-2004 summarizes the state of knowledge of highway related research into Particulate Matter (PM) pollution as determined from previous research efforts and identifies initiatives to fill gaps in knowledge...

E. Carr J. Crossett M. Grant

2002-01-01

151

CHARACTERIZATION OF PARTICULATE EMISSIONS FROM NON-FERROUS SMELTERS  

EPA Science Inventory

Chemical composition and particle size data for particulate emissions for stationary sources are required for environmental health effect assessments, air chemistry studies, and air quality modelling Investigations such as source apportionment. n this study, particulate emissions...

152

Study of Laser Backscatter by Particulates in Stack Emissions.  

National Technical Information Service (NTIS)

The validity of determining smoke plume opacity or particulate content from measurements of the backscatter of laser radiation from plume particulates was investigated. The backscatter experiments were conducted with the use of a specially designed aeroso...

E. E. Uthe C. E. Lapple

1972-01-01

153

40 CFR 60.672 - Standard for particulate matter (PM).  

Code of Federal Regulations, 2013 CFR

...false Standard for particulate matter (PM). 60.672 Section 60.672 Protection...672 Standard for particulate matter (PM). (a) Affected facilities must...bin is exempt from the applicable stack PM concentration limit (and associated...

2013-07-01

154

ASPHALTIC CONCRETE INDUSTRY PARTICULATE EMISSIONS: SOURCE CATEGORY REPORT  

EPA Science Inventory

The report describes the development of particulate emission factors based on cutoff size for inhalable particles for the asphaltic concrete industry. After review of available information characterizing particulate emissions from asphalt concrete plants, the data were summarized...

155

75 FR 17865 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Particulate Matter...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Wisconsin; Particulate Matter Standards AGENCY: Environmental Protection...The updates were made to the particulate matter standards by adding fine particulate standards...standards. EPA revised its particulate matter standards in October 2006 by...

2010-04-08

156

Indoor Air Quality Model for Particulate Matter.  

National Technical Information Service (NTIS)

The paper discusses an indoor air quality (IAQ) model for particulate matter (PM). The standard for PM<2.5 micrometers in aerodynamic diameter (PM 2.5) proposed by the U.S. EPA has produced considerable interest in indoor exposures to PM. IAQ models provi...

L. E. Sparks

2000-01-01

157

EVALUATIONS OF NOVEL PARTICULATE CONTROL DEVICES  

EPA Science Inventory

The report gives results of fractional and overall mass efficiency tests of four novel particulate control devices. Three were wet scrubbers: an Aronetics (Chemico) Two-Phase Jet Scrubber, an Entoleter Centrifield Scrubber, and a CEA Variable-Throat Venturi Scrubber. The fourth w...

158

Atmospheric particulate measurements in Norfolk, Virginia  

NASA Technical Reports Server (NTRS)

Characterization of atmospheric particulates was conducted at a site near the center of Norfolk, Virginia. Air quality was measured in terms of atmospheric mass loading, particle size distribution, and particulate elemental composition for a period of 2 weeks. The objectives of this study were (1) to establish a mean level of air quality and deviations about this mean, (2) to ascertain diurnal changes or special events in air quality, and (3) to evaluate instrumentation and sampling schedules. Simultaneous measurements were made with the following instruments: a quartz crystal microbalance particulate monitor, a light-scattering multirange particle counter, a high-volume air sampler, and polycarbonate membrane filters. To assess the impact of meteorological conditions on air quality variations, continuous data on temperature, relative humidity, wind speed, and wind direction were recorded. Particulate elemental composition was obtained from neutron activation and scanning electron microscopy analyses of polycarbonate membrane filter samples. The measured average mass loading agrees reasonably well with the mass loadings determined by the Virginia State Air Pollution Control Board. There are consistent diurnal increases in atmospheric mass loading in the early morning and a sample time resolution of 1/2 hour seems necessary to detect most of the significant events.

Storey, R. W., Jr.; Sentell, R. J.; Woods, D. C.; Smith, J. R.; Harris, F. S., Jr.

1975-01-01

159

STUDIES OF PARTICULATE REMOVAL FROM DIESEL EXHAUST  

EPA Science Inventory

The report gives results of a characterization of the collection of particulate emissions from diesel exhaust by several different methods, using 5.7 liter GM diesel engines (as sources) and such controls as fiber and gravel bed filters, trap/cyclones, and ESPs. Overall and fract...

160

PARTICULATE MATTER MULTI-YEAR PLAN  

EPA Science Inventory

EPA's research on particulate matter (PM) represents the largest portion of the Clean Air research program. In building this program, EPA has been guided by expert advice from the National Research Council of the National Academy of Sciences, and from several other organizations ...

161

REINVENTING PERSONAL EXPOSURE TO PARTICULATE MATTER  

EPA Science Inventory

Recent epidemiologic studies of modern air pollution show statistically significant relationships between fluctuations of daily non-trauma mortality and fluctuations of daily ambient particulate matter (PM) levels at low concentrations. A review of historic smoke-fog (smog)episo...

162

Enhanced Hydrophilicity of Chlorided Aluminum Oxide Particulates.  

National Technical Information Service (NTIS)

An enhancement of hydrophilicity for chlorided aluminas was demonstrated by the results obtained from gaseous H2O sorptions at 70-, 80-, and 86-percent relative humidity on alpha and gamma aluminum oxide particulates and on alpha and gamma aluminum oxide ...

W. R. Cofer

1978-01-01

163

TOTAL PARTICULATE MASS EMISSION SAMPLING ERRORS  

EPA Science Inventory

The report gives a first-cut estimate of sampling errors in the measurement of total particulate mass emissions from stationary sources. IERL-RTP Procedures Manual: Level 1 Environmental Assessment expresses the desire to measure at accuracies within a factor of + or - 2 to 3. Me...

164

HIGH TEMPERATURE PARTICULATE CONTROL WITH CERAMIC FILTERS  

EPA Science Inventory

The report gives results of an assessment of using ceramic materials as filters for fine particulate removal at high temperatures. The program was in two phases. Phase I, directed toward the development of a porous alumina membrane filter, had limited success because of the fragi...

165

TRANSGENIC MOUSE MODELS AND PARTICULATE MATTER (PM)  

EPA Science Inventory

The hypothesis to be tested is that metal catalyzed oxidative stress can contribute to the biological effects of particulate matter. We acquired several transgenic mouse strains to test this hypothesis. Breeding of the mice was accomplished by Duke University. Particles employed ...

166

Indoor particulate reactive oxygen species concentrations.  

PubMed

Despite the fact that precursors to reactive oxygen species (ROS) are prevalent indoors, the concentration of ROS inside buildings is unknown. ROS on PM2.5 was measured inside and outside twelve residential buildings and eleven institutional and retail buildings. The mean (±s.d.) concentration of ROS on PM2.5 inside homes (1.37±1.2nmoles/m(3)) was not significantly different from the outdoor concentration (1.41±1.0nmoles/m(3)). Similarly, the indoor and outdoor concentrations of ROS on PM2.5 at institutional buildings (1.16±0.38nmoles/m(3) indoors and 1.68±1.3nmoles/m(3) outdoors) and retail stores (1.09±0.93nmoles/m(3) indoors and 1.12±1.1nmoles/m(3) outdoors) were not significantly different and were comparable to those in residential buildings. The indoor concentration of particulate ROS cannot be predicted based on the measurement of other common indoor pollutants, indicating that it is important to separately assess the concentration of particulate ROS in air quality studies. Daytime indoor occupational and residential exposure to particulate ROS dominates daytime outdoor exposure to particulate ROS. These findings highlight the need for further study of ROS in indoor microenvironments. PMID:24742727

Khurshid, Shahana S; Siegel, Jeffrey A; Kinney, Kerry A

2014-07-01

167

Particulate air pollution and acute health effects  

Microsoft Academic Search

Epidemiological studies have consistently shown an association between particulate air pollution and not only exacerbations of illness in people with respiratory disease but also rises in the numbers of deaths from cardiovascular and respiratory disease among older people. Meta-analyses of these studies indicate that the associations are unlikely to be explained by any confounder, and suggest that they represent cause

A. Seaton; D. Godden; W. MacNee; K. Donaldson

1995-01-01

168

Control Techniques for Particulate Air Pollutants.  

ERIC Educational Resources Information Center

Included is a comprehensive review of the approaches commonly recommended for controlling the sources of particulate air pollution. Not all possible combinations of control techniques that might bring about more stringent control of each individual source are reviewed. The many agricultural, commercial, domestic, industrial, and municipal…

National Air Pollution Control Administration (DHEW), Washington, DC.

169

DESIGN OF A LABORATORY FOR PARTICULATE ANALYSIS  

EPA Science Inventory

The effects on human health resulting from asbestos exposure in various environments are a subject of national concern and debate. In recognition of the need for a 'state-of-the-art' laboratory for particulates analysis, with emphasis on asbestos, the Environmental Protection Age...

170

Pulse combustion drying apparatus for particulate materials  

Microsoft Academic Search

This patent describes a pulse jet combustion apparatus for the drying of particulate material of the type having: a combustion chamber having an air entry end, an exhaust end and a common longitudinal axis therebetween, an air inlet conduit coaxially connected to the air entry and thereof, a primary exhaust gas conduit coaxially connected to the exhaust end thereof and,

R. R. Gray; V. M. Marguth

1987-01-01

171

Positive artifact in the measurement of particulate carbonaceous substances using an ambient carbon particulate monitor  

NASA Astrophysics Data System (ADS)

An ambient carbon particulate monitor (ACPM), which is a commercially available instrument for automatic continuous measurement of particulate carbon, has been used in the recent studies. In order to investigate the amount of the positive artifact in the measurement of particulate carbonaceous substances by the ACPM, field duplicate experiments using two ACPMs and a parallel plate organic denuder were conducted in urban and rural atmosphere. The ACPM measurements without the denuder are at risk of overestimating the results for organic carbon (OC) and total carbon in aerosols because of the positive artifact derived from organic vapors in the sample air stream. On the other hand, the measurement of OC evolved at higher temperatures (250-340°C) and elemental carbon in aerosols are not significantly affected by the positive artifact. The ACPM measurements with the denuder give the lower-limit concentrations of particulate carbonaceous substances.

Matsumoto, Kiyoshi; Hayano, Teruaki; Uematsu, Mitsuo

172

Source apportionment of particulate matter in Denmark  

NASA Astrophysics Data System (ADS)

Atmospheric particulate matter (PM) has received considerable attention over the last decade as an important component of air pollution, particularly due to its health effects on the exposed population. Typically the mass of particles with diameters smaller that 10 ?m (PM10) has been used in large cohort studies to estimate health effects such as increase in hospitalization rate, asthma attacks and premature deaths. Particles smaller than 2.5 ?m (PM2.5) and ultra fine particles have been used in various epidemiological studies and correlations between exposure to fine and ultra fine particles and health effects have been found. Limits of acceptable concentrations of PM10, PM2.5 and some carcinogenic species have been made, and it is important to find the origin of the particulate matter to prevent exceeds of these limits. This can be done by measuring particle mass, organic/inorganic fractions of particles, the chemical components and other relevant factors, and then use receptor modeling for source apportionment of the particulate matter. We have done measurements at street level and urban background in Copenhagen, Denmark, to determine the origin of different sizes of particulate matter and the toxic organic compounds connected to these particles. We also did measurements in a small village with less traffic and more residential wood combustion for a comparison between traffic and wood combustion generated pollution. Our results show a significant amount of particulate matter coming from non local sources and are dominated by long-range transported inorganic salts. The amount of these is highly depended on the wind direction and thus on the origin of the wind plume. The origin of the carcinogenic organic compound benzo(a)pyrene was found to be local combustion sources. To prevent events of high particulate matter concentration in Copenhagen, Denmark, a reduction of emission from the local traffic will only lead to a minor effect, since the majority of the particulate matter is from long-range transport. A reduction in combustion generated particles would lead to a significant decrease in the smallest particle sizes and in the concentration of traffic generated toxics like benzo(a)pyrene.

Moenster, J.; Glasius, M.; Nielsen, O. J.; Bilde, M.; Jensen, F. P.

2005-12-01

173

Electrically heated particulate filter preparation methods and systems  

DOEpatents

A control system that controls regeneration of a particulate filter is provided. The system generally includes a fuel control module that controls injection of fuel into exhaust that passes through the particulate filter. A regeneration module controls current to the particulate filter to initiate regeneration after the fuel has been injected into the exhaust.

Gonze, Eugene V [Pinckney, MI

2012-01-31

174

40 CFR 60.302 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standard for particulate matter. 60.302 Section 60.302 Protection... § 60.302 Standard for particulate matter. (a) On and after the 60th...emission which: (1) Contains particulate matter in excess of 0.023 g/dscm (ca....

2013-07-01

175

40 CFR 60.282 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standard for particulate matter. 60.282 Section 60.282 Protection... § 60.282 Standard for particulate matter. (a) On and after the date on...gases which: (i) Contain particulate matter in excess of 0.10 g/dscm...

2013-07-01

176

Diesel exhaust particulate and organic vapor emission control  

Microsoft Academic Search

A system for controlling emissions of particulates and heavy organic vapors in the exhaust gases of diesel engines includes, in a preferred embodiment, a heat exchanger for cooling the engine exhaust gases below the condensation temperature of the organic vapors and their resultant adsorption onto the entrained particulates, and a particulate trap connected to receive the cooled gases from the

Mann

1982-01-01

177

CHARACTERIZATION OF PARTICULATE EMISSIONS FROM IN-USE DIESEL VEHICLES  

EPA Science Inventory

Particulate emissions data are presented from a group of 19 in-use diesel automobiles. Five driving cycles and three fuel/lubricating oil combinations have been used to obtain particulate emissions data and also to collect particulate samples for chemical and bioassay characteriz...

178

Relationship between indoor and outdoor carbonaceous particulates in roadside households  

Microsoft Academic Search

Concentrations of particulate matter (PM) and carbonaceous particulates in indoor and outdoor air at roadside private households were measured in Osaka, Japan. The particulate samples were collected on filters using a portable AND sampler capable of separating particles into three different size ranges: over 10 ?m, 2–10 ?m (coarse) and below 2 ?m (fine) in aerodynamic diameter. The filters were

K. Funasaka; T. Miyazaki; K. Tsuruho; K. Tamura; T. Mizuno; K. Kuroda

2000-01-01

179

Relationships between Total Suspended Particulate, Sulfate, and Respirable Suspended Particulate Concentrations. Analysis of Data Collected in New York City.  

National Technical Information Service (NTIS)

Two years of data for daily total suspended particulate, sulfate, and respirable suspended particulate concentrations measured at four stations in the New York City area are statistically analyzed. To show the variability of each pollutant data set, the m...

G. A. DeMarrais

1979-01-01

180

Diethyl pyrocarbonate inactivates CD39\\/ecto-ATPDase by modifying His59  

Microsoft Academic Search

Diethyl pyrocarbonate (DEPC) in conditions that favour carbethoxylation of histidyl residues strongly inactivated E-type ATPase activity of a rat lung membrane preparation, as well as ecto-ATPase activity of rat vessels and human Epstein–Barr virus-transformed B lymphocytes. Inactivation of the enzyme (up to 70%) achieved at concentrations of DEPC below 0.5 mM could be fully reversed by 200 mM hydroxylamine at

Karine N. Dzhandzhugazyan; Liselotte Plesner

2000-01-01

181

NTPDase1 (CD39) controls nucleotide-dependent vasoconstriction in mouse  

PubMed Central

Aims Extracellular nucleotides are vasoactive molecules. The concentrations of these molecules are regulated by ectonucleotidases. In this study, we investigated the role of the blood vessel ectonucleotidase NTPDase1, in the vasoconstrictor effect of nucleotides using Entpd1?/? mice. Methods and results Immunofluorescence, enzyme histochemistry, and HPLC analysis were used to evaluate both NTPDase expression and activity in arteries and isolated vascular smooth muscle cells (VSMCs). Vascular reactivity was evaluated in vitro and mean arterial blood pressure was recorded in anesthetized mice after nucleotide i.v. infusion. Expression of nucleotide receptors in VSMCs was determined by RT–PCR. Entpd1?/? mice displayed a dramatic deficit of nucleotidase activity in blood vessel wall in situ and in VSMCs in comparison to control mice. In aortic rings from Entpd1?/? mice, UDP and UTP induced a potent and long-lasting constriction contrasting with the weak response obtained in wild-type rings. This constriction occurred through activation of P2Y6 receptor and was independent of other uracil nucleotide-responding receptors (P2Y2 and P2Y4). UDP infusion in vivo increased blood pressure and this effect was potentiated in Entpd1?/? mice. In addition, pressurized mesenteric arteries from Entpd1?/? mice displayed an enhanced myogenic response, consistent with higher local concentrations of endogenously released nucleotides. This effect was inhibited by the P2 receptor antagonist RB-2. Conclusion NTPDase1 is the major enzyme regulating nucleotide metabolism at the surface of VSMCs and thus contributes to the local regulation of vascular tone by nucleotides.

Kauffenstein, Gilles; Drouin, Annick; Thorin-Trescases, Nathalie; Bachelard, Helene; Robaye, Bernard; D'Orleans-Juste, Pedro; Marceau, Francois; Thorin, Eric; Sevigny, Jean

2013-01-01

182

Particulate Concentration Levels in Chinatown, Oakland, California  

NASA Astrophysics Data System (ADS)

Chinatown is located near the center of the busy business district of downtown Oakland, California. It is one of the most inhabited and congested areas in the City of Oakland, averaging 4,000 vehicles and 3,000 pedestrians per hour at a key intersection in the center of the neighborhood. Particles produced by automobiles and construction can settle into the bronchi of lungs and induce asthma attacks, irritate cardiovascular tissue, and possibly lead to lung cancer and death. Particulate pollution is a serious problem that is estimated to cause between 20,000 and 50,000 deaths per year in the US alone. Hence, evaluation of the air quality of the Chinatown neighborhood is important, because it helps to address issues that are of great concern to residents of the area. The primary goal of our project was to measure particulate concentration levels at various intersections in Oakland's Chinatown to determine if the air quality met U.S. EPA standards, and to take note of any trends that may occur over a period of months. We were primarily concerned with particles that are 2.5 micrometers diameter and smaller, as smaller particles are easily inhaled and directly affect the respiratory system. We were interested in identifying any intersections that may have had significantly higher levels than other intersections. Using a map of Chinatown, we chose 12 intersections and made measurements at these points over the course of six months, beginning in February and ending in July of 2007. Particulate matter measurements were made using a FLUKE 893 Particle Counter. Measurements recorded on the first day of our study, February 4, 2007, which was the day of an annual street festival, yielded the highest values for particulate matter concentration in our dataset. This was followed by a significant drop in concentration the following week, and then a gradual increase of concentration as the months progressed. No one location yielded values significantly higher than any other, and, except for the first and last day (where there was experimental error), recorded values seem to meet EPA standards. We conclude that the high particulate matter levels we observed were due to heavy crowding and traffic jams near street corners during the time of the festival. We also conclude that particulate pollution levels in the Chinatown neighborhood are generally acceptable, except during festivities that generate heavy congestion. We intend conduct further investigations, particularly at next year's street festival, to confirm observations made thus far.

Chen, B.; Yeung, A.; Yu, J. F.

2007-12-01

183

Particulate silicon nitride-based composites  

SciTech Connect

In an attempt to optimize the structure and properties of silicon nitride ceramics, a variety of novel processing techniques and materials compositions have evolved over the last 15 years. Among the most important, was the development of various silicon nitride-based composites. A review of particulate, silicon nitride-based composites other than whisker- or platelets-reinforced, is presented. Materials based on silicon nitride and SiALONs, with additions of carbides, nitrides and borides of transition metals are described. Special emphasis is placed on TiN- and TiC-containing ceramics. The manufacture of composites by hot pressing, reaction sintering, pressureless and gas-pressure sintering is discussed. The data on properties, including conductivity, density, Young`s modulus, strength, fracture toughness, hardness, thermal expansion, wear, creep and oxidation resistance are presented. Analysis of actual and potential uses of the selected composites demonstrates that the particulate composites are very promising as tool, structural and electronic materials. 119 refs.

Gogotsi, Y.G. [Tokyo Institute of Technology, Yokohama (Japan)

1994-05-01

184

NICKEL SPECIATION OF URBAN PARTICULATE MATTER  

SciTech Connect

A four-step sequential Ni extraction method, summarized in Table AB-1, was evaluated for identifying and quantifying the Ni species occurring in urban total suspended particulate (TSP) matter and fine particulate matter (<10 {micro}m [PM{sub 10}] and <2.5 {micro}m [PM{sub 2.5}] in aerodynamic diameter). The extraction method was originally developed for quantifying soluble, sulfidic, elemental, and oxidic forms of Ni that may occur in industrial atmospheres. X-ray diffraction (XRD) and x-ray absorption fine structure (XAFS) spectroscopy were used to evaluate the Ni species selectivity of the extraction method. Uncertainties in the chemical speciation of Ni in urban PM{sub 10} and PM{sub 2.5} greatly affect inhalation health risk estimates, primarily because of the large variability in acute, chronic, and cancer-causing effects for different Ni compounds.

Kevin C. Galbreath; Charlene R. Crocker; Carolyn M. Nyberg; Frank E. Huggins; Gerald P. Huffman

2003-10-01

185

Apparatus for measuring surface particulate contamination  

DOEpatents

An apparatus for measuring surface particulate contamination includes a tool for collecting a contamination sample from a target surface, a mask having an opening of known area formed therein for defining the target surface, and a flexible connector connecting the tool to the mask. The tool includes a body portion having a large diameter section defining a surface and a small diameter section extending from the large diameter section. A particulate collector is removably mounted on the surface of the large diameter section for collecting the contaminants. The tool further includes a spindle extending from the small diameter section and a spool slidingly mounted on the spindle. A spring is disposed between the small diameter section and the spool for biasing the spool away from the small diameter section. An indicator is provided on the spindle so as to be revealed when the spool is pressed downward to compress the spring.

Woodmansee, Donald E. (Simpsonville, SC)

2002-01-01

186

Effects of particulate air pollution on asthmatics  

SciTech Connect

Twenty-four asthmatic subjects in Denver were followed from January through March 1979, a three-month period in which Denver air pollution levels are generally high and variable. Dichotomous, virtual impactor samplers provided daily measurements (micrograms/m3) of inhaled particulate matter (total mass, sulfates, and nitrates) for coarse (2.5--15 micrograms in aerodynamic diameter) and fine fractions (less than 2.5 micrometers). Carbon monoxide, sulfur dioxide, ozone, temperature, and barometric pressure were also measured. Twice daily measurements of each subject's peak expiratory flow rates, use of as-needed aerosolized bronchodilators, and report of airways obstruction symptoms characteristic of asthma were tested for relationships to air pollutants using a random effects model across subjects. During the time actually observed, there were very few days in which high levels of suspended particulates were recorded. Of the environmental variables studied, only fine nitrates were associated with increased symptom reports and increased aerosolized bronchodilator usage.

Perry, G.B.; Chai, H.; Dickey, D.W.; Jones, R.H.; Kinsman, R.A.; Morrill, C.G.; Spector, S.L.; Weiser, P.C.

1983-01-01

187

Face crack reduction strategy for particulate filters  

DOEpatents

A system comprises a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion. A control module initiates combustion of PM in the PM filter using a heater and selectively adjusts oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter. A method comprises providing a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion; initiating combustion of PM in the PM filter using a heater; selectively adjusting oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter.

Gonze, Eugene V [Pinckney, MI

2012-01-31

188

Toxicity of inhaled traffic related particulate matter  

NASA Astrophysics Data System (ADS)

Traffic generated ultrafine particulates may play a major role in the development of adverse health effects. However, little is known about harmful effects caused by recurring exposure. We hypothesized that repeated exposure to particulate matter results in adverse pulmonary and systemic toxic effects. Exposure to diesel engine exhaust resulted in signs of oxidative stress in the lung, impaired coagulation, and changes in the immune system. Pro-inflammatory cytokine levels were decreased in some regions of the brain but increased in the striatum implying that exposure to diesel engine exhaust may selectively aggravate neurological impairment. Data from these three studies suggest that exposure to traffic related PM can mediate changes in the vasculature and brain of healthy rats. To what extent these changes may contribute to chronic neurodegenerative or vascular diseases is at present unclear.

Gerlofs-Nijland, Miriam E.; Campbell, Arezoo; Miller, Mark R.; Newby, David E.; Cassee, Flemming R.

2009-02-01

189

Synthesis and properties of nanofunctionalized particulate materials  

Microsoft Academic Search

A wide range of advanced technology for existing and emerging products based on high temperature metal-ceramic composites used in aircrafts, cutting tools, lithium-ion based rechargeable batteries, superconductors, field emission based flat-panel displays, etc. employ micron to submicron sized (0.1–10 microns) particulate precursors in their manufacturing process. Although there has been a significant emphasis given to control of the particle characteristics

J. Fitz-Gerald; S. Pennycook; H. Gao; R. K. Singh

1999-01-01

190

Recent observations of particulates in Nitinol  

Microsoft Academic Search

In spite of 40 years of history of Nitinol, the issues regarding its inclusions have been poorly explored. In our brief studies, conducted within the projects on surface design using Auger, energy-dispersive X-ray spectroscopy and scanning electrons microscopy, we discovered that particulates in NiTi medical alloys were always based on Ti: either ?Ti2NiO oxide, titanium dioxide, titanium carbide or oxidized

S. Shabalovskaya; J. Anderegg; J. Van Humbeeck

2008-01-01

191

#61 Particulate air pollution and lung cancer  

Microsoft Academic Search

PURPOSE: To evaluate the association between particulate air pollution and lung cancer in a retrospective study in Connecticut, Utah and southern Idaho.METHODS: We collected detailed residence histories from 1,474 pathologically confirmed lung cancer cases and 1,811 population controls selected with randomized recruitment. Analysis was limited to the 3,073 participants who lived only in Connecticut, Utah and Idaho during the period

W Sanasuttipun; DP Sandler; CR Weinberg; DL Shore; CM Shy; DP Loomis

2002-01-01

192

Self-Cleaning Particulate Prefilter Media  

NASA Technical Reports Server (NTRS)

A long-term space mission requires efficient air revitalization performance to sustain the crew. Prefilter and particulate air filter media are susceptible to rapid fouling that adversely affects their performance and can lead to catastrophic failure of the air revitalization system, which may result in mission failure. For a long-term voyage, it is impractical to carry replacement particulate prefilter and filter modules due to the usual limitations in size, volume, and weight. The only solution to this problem is to reagentlessly regenerate prefilter and filter media in place. A method was developed to modify the particulate prefilter media to allow them to regenerate reagentlessly, and in place, by the application of modest thermocycled transverse or reversed airflows. The innovation may allow NASA to close the breathing air loop more efficiently, thereby sustaining the vision for manned space exploration missions of the future. A novel, self-cleaning coatings technology was developed for air filter media surfaces that allows reagentless in-place regeneration of the surface. The technology grafts thermoresponsive and nonspecific adhesion minimizing polymer nanolayer brush coatings from the prefilter media. These polymer nanolayer brush architectures can be triggered to contract and expand to generate a "pushing-off" force by the simple application of modestly thermocycled (i.e. cycling from ambient cabin temperature to 40 C) air streams. The nonspecific adhesion-minimizing properties of the coatings do not allow the particulate foulants to adhere strongly to the filter media, and thermocycled air streams applied to the media allow easy detachment and in-place regeneration of the media with minimal impact in system downtime or astronaut involvement in overseeing the process.

Weber, Olivia; Lalwani, San-jiv; Sharma, Anjal

2012-01-01

193

Particulate Emissions from On-Road Vehicles  

Microsoft Academic Search

\\u000a The short term standard defined by the European Union (Directive 2008\\/50\\/EC) (European Parliament, Council of the European\\u000a Union 2008) for particulate matter smaller than 10 ?m (PM10) is violated in many European cities (Querol et al. 2004; Van Dingenen et al. 2004), therefore the current air quality status of PM10 is under investigation in many countries, in particular to understand the

Andreas Limbeck; Christoph Puls

194

Effects of particulate air pollution on asthmatics  

Microsoft Academic Search

Twenty-four asthmatic subjects in Denver were followed from January through March 1979, a three-month period in which Denver air pollution levels are generally high and variable. Dichotomous, virtual impactor samplers provided daily measurements (micrograms\\/m3) of inhaled particulate matter (total mass, sulfates, and nitrates) for coarse (2.5--15 micrograms in aerodynamic diameter) and fine fractions (less than 2.5 micrometers). Carbon monoxide, sulfur

G. B. Perry; H. Chai; D. W. Dickey; R. H. Jones; R. A. Kinsman; C. G. Morrill; S. L. Spector; P. C. Weiser

1983-01-01

195

Fatigue crack propagation testing of particulate MMCs  

Microsoft Academic Search

A brief review of the existing data in the literature for long crack fatigue propagation rates in particulate reinforced metal matrix composites is presented. Crack growth rates are found to fall within a relatively narrow scatter band with thresholds in the range 2.5-4.7 MPa sq rt m at R = 0.1. In general, standard fatigue testing techniques, as applied to

D. M. Knowles; J. E. King

1991-01-01

196

Prediction of particulate contamination on aperture window  

NASA Technical Reports Server (NTRS)

This paper presents an analysis to predict the effects of light scattering by surface particles on the sensor window of a missile during ascent flight. The particulate contaminant distribution on the window is calculated by tallying the number of particles in a set of size ranges. The particulate contamination at the end of the mission is predicted by adding the contributions from the events of ground and flight operations. The surface particle redistributions caused by vibroacoustically induced surface acceleration was found to contribute the most of the particulate surface contamination. The analytical surface obscuration calculation with a set of particle counts was compared to the results of image analyzer measurement. The analytical results, which were calculated with a given function of particle shape depending on the size, were more conservative than the measurement. A scattering calculation using a verified BSDF model showed that the scattering was less than 0.001 at 20 off the direction of the incident light in the mid IR wavelength when the surfaces were at Level 300 initially.

Lee, Aleck L.; Fong, Michael C.

1994-01-01

197

ADVANCED HYBRID PARTICULATE COLLECTOR - PHASE III  

SciTech Connect

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. In Phase II, a 2.5-MW-scale AHPC was designed, constructed, installed, and tested at the Big Stone power station. For Phase III, further testing of an improved version of the 2.5-MW-scale AHPC at the Big Stone power station is being conducted to facilitate commercialization of the AHPC technology.

Stanley J. Miller; Ye Zhuang; Michael E. Collings; Michelle R. Olderbak

2000-10-01

198

ADVANCED HYBRID PARTICULATE COLLECTOR - PHASE III  

SciTech Connect

A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. In Phase II, a 2.5-MW-scale AHPC was designed, constructed, installed, and tested at the Big Stone power plant. For Phase III, further testing of an improved version of the 2.5-MW-scale AHPC at the Big Stone power plant is being conducted to facilitate commercialization of the AHPC technology.

Stanley J. Miller; Ye Zhuang; Michelle R. Olderbak

2001-04-01

199

Elemental analysis of airborne particulates in Chile.  

PubMed

Aerosol samples collected in three characteristic Chilean cities-including urban and remote zones-have been analyzed by the PIXE spectroscopic technique. Elemental composition, total suspended particulate matter (TSP), particle size distribution, and the peculiar geographic and meteorological parameters have been included in this study. Santiago--the polluted capital of Chile--registered high TSP indexes and important amounts of hazardous elements in air such as S, V, Cr, Zn, Br and Pb. The atmosphere of Antofagasta city showed marine and mineral activity influence. Results from Chillán city are similar to those from rural environments. Protons and deuterons-provided by the isochronous cyclotron of the University of Chile-were used to excite X-ray radiation from the sample. Signals were processed by an energy dispersive detection system, including a cryogenic Si(Li) detector, electronic for pulse amplification and an analog to digital converter. The absolute elemental concentration of the particulate matter in air was obtained through a fundamental parameter equation. Samples consist of particulate material collected directly on Nuclepore filters or deposited over Kapton foils. Typical elements analyzed were Mg, Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Cu, Zn, As, Br and Pb. PMID:15092200

Romo-Kröger, C M

1990-01-01

200

Flashlamp measurement of the MSX particulate environment  

NASA Astrophysics Data System (ADS)

The xenon flashlamp is one of a suite of instruments that monitor the particulate and gaseous contamination environments of the midcourse space experiment (MSX) spacecraft. The near-field particulate measurement comprises the high intensity xenon flashlamp that illuminates a volume of space in the field of view of the UVISI wide field of view visible imager (UVISI IVW). Radiation scattered by illuminated contaminant particles is imaged by the IVW. The intensity of the radiation is related to a particle's size and composition. The particle's track yields information about its velocity and trajectory. From ground calibration data we estimate a sensitivity to detect particles smaller than 1 micrometer and to determine cross-field velocities from 1 mm/sec to 50 m/sec. The visible radiation measurement of the particulate environment provided by the xenon flashlamp and UVISI IVW is complemented by multiband IR, UV, and visible measurements by other MSX sensors. The early mission data from this experiment will quantify the relationship between ground contamination control measures, the on-orbit contamination environment, and the performance history of on-orbit sensors.

Galica, Gary E.; Green, B. David; Atkinson, John J.; Aurilio, Giuseppe; Shepherd, Orr; Lesho, Jeffrey C.; Uy, O. Manuel

1996-11-01

201

Characterizing the origins of atmospheric particulate matter  

NASA Astrophysics Data System (ADS)

When developing policy targeted at decreasing air pollution, it is essential that we have a strong understanding of when and where the pollution originated. Towards this goal, we have implemented and evaluated two different source attribution schemes in PMCAMx, a three-dimensional atmospheric chemical transport model. The two schemes, an online (OPSA) and offline version (PSAT), are both designed for computational efficiency and the ability to track source contributions to primary and secondary particulate matter. The two versions showed good agreement with each other and with more accurate, computationally demanding methods. The off-line algorithm (Particulate Source Apportionment Technology, PSAT) is simpler to implement, has a lower computational cost and is suitable for a range of source apportionment studies. We have utilized this algorithm to study the age distribution of atmospheric particulate matter mass in space and time. The average calculated ages are on the order of a few days for particulate matter near the ground, but are highly variable in space and time. Primary aerosol species had average ages of approximately 24 hours over this polluted continental region while the average ages for secondary species were 48-72 hours near the surface. As expected, the average age of all aerosol components increases vertically in the atmosphere. Age increases rapidly away from the sources of aerosol and its precursors and for non-volatile species it increases with particle size. PSAT is an excellent tool for the study of source-receptor relationships. We have studied the extent of pollutant transport in the Eastern United States using two approaches. The first PSAT-based approach is focused on source regions and the second is focused on receptor regions. For the source region focused approach, transport of pollutants is quantified by tracking the emissions from these regions. For the receptor region focused approach, PSAT tracks the pollutants emitted from a series of rings around the area of interest We discuss the results from these approaches looking at the impacts to primary elemental carbon, SO2, particulate sulfate and secondary organic aerosol. The source region-focused approach was applied to study the contributions to PM levels of 11 different area in the Eastern United States, ranging in size (both in terms of land area and emissions) from the Ohio River Valley to Little Rock, AR. These impacts were quantified using a variety of measures to account for both the distance that the pollutants are transported and the overall impact the emissions have on pollutant concentrations in the region. Large source regions were found to have a large impact on secondary particulate matter levels areas several hundred kilometers from the source region. The receptor region focused approach was used to evaluate the contributions from long range, mid range and long range transport to particulate matter concentrations in three receptor regions: Pittsburgh, PA, Atlanta, GA and Great Smoky Mountains. The local impacts to elemental carbon in urban areas were found to be substantial (approximately 50%) with most the additional contributions being from short range transport. The contributions to sulfate and SOA were found to be more regional with much of the contributions in all three sites resulting from mid range transport.

Wagstrom, Kristina Michelle

202

Estimates of particulate mass in multi-canister overpacks  

SciTech Connect

High, best estimate, and low values are developed for particulate inventories within MCO baskets that have been loaded with freshly cleaned fuel assemblies and scrap. These per-basket estimates are then applied to all anticipated MCO payload configurations to identify which configurations are bounding for each type of particulate. Finally the resulting bounding and nominal values for residual particulates are combined with corresponding values [from other documents] for particulate that may be generated by corrosion of exposed uranium after the fuel has been cleaned. The resulting rounded nominal estimate for a typical MCO after 40 years of storage is 8 kg. The estimate for a bounding total particulate case MCO is that it may contain up to 64 kg of particulate after 40 years of storage.

SLOUGHTER, J.P.

1999-02-25

203

Mécanismes d'éjection de particules par laser impulsionnel  

NASA Astrophysics Data System (ADS)

L'enlèvement de particules de dimensions nanométriques est l'un des principaux challenges à relever pour atteindre les futurs objectifs de l'industrie microélectronique. Les procédés laser présentent, dans certains cas, des performances très intéressantes, mais les mécanismes d'éjection des particules polluant la surface restent cependant fort mal connus. L'étude de la dynamique d'éjection des particules, par une technique optique, a mis en évidence l'existence de deux mécanismes dont l'importance relative dépend de la fluence d'irradiation. A forte fluence l'ablation locale du substrat sous la particule prédomine, alors que pour les fluences plus faibles le mécanisme semble être lié à l'enlèvement de l'humidité résiduelle à l'interface particule substrat. Contrairement aux modèles précédemment proposés, la contribution de la force d'inertie s'exerçant sur la particule lors de l'expansion thermique rapide des matériaux est négligeable.

Grojo, D.; Cros, A.; Delaporte, Ph.; Sentis, M.; Dubus, H.; Mionetto, R.

2006-12-01

204

Estimates of Particulate Mass in Multi Canister Overpacks (MCO)  

SciTech Connect

High, best estimate, and low values are developed for particulate inventories within MCO baskets that have been loaded with freshly cleaned fuel assemblies and scrap. These per-basket estimates are then applied to all anticipated MCO payload configurations to identify which configurations are bounding for each type of particulate. Finally the resulting bounding and nominal values for residual particulates are combined with corresponding values [from other documents] for particulates that may be generated by corrosion of exposed uranium after the fuel has been cleaned. The resulting rounded nominal estimate for a typical MCO after 40 years of storage is 8 kg. The estimate for a bounding total particulate case MCO is that it may contain up to 64 kg of particulate after 40 years of storage.

SLOUGHTER, J.P.

2000-02-16

205

Diesel particulate filter regeneration via resistive surface heating  

DOEpatents

An exhaust system that processes exhaust generated by an engine is provided. The system includes: a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine; and a grid of electrically resistive material that is applied to an exterior upstream surface of the PF and that selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF.

Gonze, Eugene V; Ament, Frank

2013-10-08

206

Shielded regeneration heating element for a particulate filter  

DOEpatents

An exhaust system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A catalyst substrate or a flow converter is disposed upstream from said heating element. The catalyst substrate oxidizes the exhaust prior to reception by the heating element. The flow converter converts turbulent exhaust flow to laminar exhaust flow prior to reception by the heating element.

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-01-04

207

Electrically heated particulate filter regeneration using hydrocarbon adsorbents  

DOEpatents

An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material selectively heats exhaust passing through the upstream end to initiate combustion of particulates within the PF. A hydrocarbon adsorbent coating applied to the PF releases hydrocarbons into the exhaust to increase a temperature of the combustion of the particulates within the PF.

Gonze, Eugene V [Pinckney, MI

2011-02-01

208

Flight prototype regenerative particulate filter system development  

NASA Technical Reports Server (NTRS)

The effort to design, fabricate, and test a flight prototype Filter Regeneration Unit used to regenerate (clean) fluid particulate filter elements is reported. The design of the filter regeneration unit and the results of tests performed in both one-gravity and zero-gravity are discussed. The filter regeneration unit uses a backflush/jet impingement method of regenerating fluid filter elements that is highly efficient. A vortex particle separator and particle trap were designed for zero-gravity use, and the zero-gravity test results are discussed. The filter regeneration unit was designed for both inflight maintenance and ground refurbishment use on space shuttle and future space missions.

Green, D. C.; Garber, P. J.

1974-01-01

209

Electrically heated particulate filter with reduced stress  

DOEpatents

A system comprises a particulate matter (PM) filter comprising an inlet for receiving exhaust gas. A zoned heater is arranged in the inlet and comprises a resistive heater comprising N zones, where N is an integer greater than one. Each of the N zones comprises M sub-zones, where M is an integer greater than one. A control module selectively activates one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates others of the N zones.

Gonze, Eugene V.

2013-03-05

210

Pilot indoor-outdoor study of organic particulate matter and particulate mutagenicity  

SciTech Connect

Elevated indoor concentrations of a number of gaseous and particulate pollutants have been demonstrated by numerous workers. The case of indoor to outdoor (I/O) relationships for particulate organic matter, however, is especially complex in view of the range of organic compounds in this fraction and the need for relatively sensitive analytical techniques and large sampled air volumes. Thus, it is not surprising that relatively little attention has been given to the characterization of particulate organic matter indoors. Indoor sources of organic pollutants, such as tobacco smoke, fireplaces and woodburning stoves, kerosene heaters, gas stoves, cooking, and attached garages may constitute the foremost air pollution hazard in some homes, depending upon season. Infiltration of outdoor organics would depend upon season and the lifestyle of the inhabitants. The pilot study reported here addresses: certain quantitative and qualitative summertime I/O relationships among selected airborne particulate organic pollutants, the I/O relationships for the bacterial mutagenicity of the extractable organic matter,and the nature of the EOM found in a home without central air conditioning during the summertime, which is a situation that can occur in many northern cities.

Lioy, P.J.; Avdenko, M.; Harkov, R.; Atherholt, T.; Daisey, J.M.

1985-06-01

211

The Effect of Viewing Order of Macroscopic and Particulate Visualizations on Students' Particulate Explanations  

ERIC Educational Resources Information Center

A prior study showed that students best make predictions about the outcome of opening a valve between two flasks containing a fluid or vacuum when they view both a demonstration video and a particulate animation, but the study showed no influence from the order in which these visualizations were used. The purpose of this current research was to…

Williamson, Vickie M.; Lane, Sarah M.; Gilbreath, Travis; Tasker, Roy; Ashkenazi, Guy; Williamson, Kenneth C.; Macfarlane, Ronald D.

2012-01-01

212

40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.  

Code of Federal Regulations, 2010 CFR

...instrumentation calibration; particulate, methanol, and formaldehyde measurement...instrumentation calibration; particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

2009-07-01

213

40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.  

Code of Federal Regulations, 2010 CFR

...instrumentation calibration; particulate, methanol and formaldehyde measurement. 86...instrumentation calibration; particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions...

2010-07-01

214

Enhanced hydrophilicity of chlorided aluminum oxide particulates  

NASA Technical Reports Server (NTRS)

An enhancement of hydrophilicity for chlorided aluminas was demonstrated by the results obtained from gaseous H2O sorptions at 70-, 80-, and 86-percent relative humidity on alpha and gamma aluminum oxide particulates and on alpha and gamma aluminum oxide particulates with a chemisorbed surface chloride phase (produced by reactions of gaseous HCl + H2O on alumina). Continuous sorption histories for H2O on chlorided aluminas having specific surface areas that range from 7 to 227 sq m/g before chloriding indicated that initial sorption rates were directly linked to the extent of chemisorbed chlorided coverage and implied the same relationship for sorption capacities. The initial sorption rate on chlorided aluminas was found to be slower for the first exposure to H2O than for subsequent exposures (which reached equilibrated H2O coverages much faster), suggesting that slow chemical reactions between H2O and chlorided alumina may have been operative during initial exposures. Chlorided alumina particles were found to remain very hydrophilic (relative to nonchlorided analogs) for several H2O sorption/desorption cycles.

Cofer, W. R., III

1978-01-01

215

Jammed particulate systems are inherently nonharmonic  

NASA Astrophysics Data System (ADS)

Normal mode analysis in the harmonic approximation underlies most of solid-state physics and applies well to both ordered and dis- ordered systems. Naturally, researches apply this analysis to jammed particulate systems, such as granular media, colloids, and foams, that interact via one-sided interactions, which are nonzero only when particles overlap. However, we find that systems with one-sided repulsive interactions possess no linear, harmonic response regime for large systems (N->?) at finite pressures P, and for all N near jamming onset P->0. We perform simulations on 2D frictionless bidisperse mechanically stable disk packings over a range of packing fractions ??= ?-?J above jamming onset ?J. We apply perturbations with amplitude ? to the packings along each eigen-direction from the dynamical matrix and determine whether the response of the system evolving at constant energy remains in the original eigenmode of the perturbation. For ?> ?c, a single contact breaks and fluctuations abruptly spread to all discrete harmonic modes. As ? increases further all harmonic modes disappear into a continuous frequency band. We find that ?c˜??/N, and thus jammed particulate systems are inherently nonharmonic with no linear vibrational response regime as N->? over the full range of ??, and as ??->0 at any N. This breakdown of harmonic behavior dramatically affects all aspects of system response including heat capacity, density of states, elastic moduli, and energy propagation.

Shattuck, Mark D.

2011-03-01

216

Effects of particulate air pollution on asthmatics  

SciTech Connect

Twenty-four asthmatic subjects in Denver were followed from January through March 1979, a three-month period in which Denver air pollution levels are generally high and variable. Dichotomous, virtual impactor samplers provided daily measurements (..mu..g/m/sup 3/) of inhaled particulate matter (total mass, sulfates, and nitrates) for coarse (2.5-15 ..mu..m in aerodynamic diameter) and fine fractions (<2.5 ..mu..m). Carbon monoxide, sulfur dioxide, ozone, temperature, and barometric pressure were also measured. Twice daily measurements of each subject's peak expiratory flow rates, use of as-needed aerosolized bronchodilators, and report of airways obstruction symptoms characteristic of asthma were tested for relationships to air pollutants using a random effects model across subjects. During the time period actually observed, there were very few days in which high levels of suspended particulates were recorded. Of the environmental variables studied, only fine nitrates were associated with increased symptom reports and increased aerosolized bronchodilator usage.

Perry, G.B. (Univ. of Colorado Health Sciences Center, Denver); Chai, H.; Dickey, D.W.; Jones, R.H.; Kinsman, R.A.; Morrill, C.G.; Spector, S.L.; Weiser, P.C.

1983-01-01

217

Particulate Cytochromes of Mung Bean Seedlings 1  

PubMed Central

Efforts have been made to solubilize cytochrome components from particulate fractions of etiolated mung bean seedlings. Low temperature spectrophotometry reveals that the cytochrome composition of mitochondria isolated from whole seedlings is the same as that reported by Bonner for mung bean hypocotyls. On the basis of the identity in position of the ?-bands in low temperature difference spectra for mitochondria, for a partially purified haemoprotein from mitochondria, and for purified cytochrome b-555, it is suggested that cytochrome b-555 is an intrinsic component of mung bean mitochondria. Difference spectra show that both the mitochondrial and microsomal fractions contain at least 2 b-type cytochromes. Cytochrome b-555 is almost certainly present in the microsomes, since the low temperature difference spectrum for the cytochrome is identical with the spectrum for this particulate fraction. By freezing and thawing mung bean mitochondria in 4% cholate and centrifuging, cytochrome oxidase activity can be concentrated in the supernatant fraction, although it is not completely solubilized. The oxidase is inhibited by high concentrations of cytochrome c. A particle-bound cytochrome c can be obtained from mitochondria by digestion with snake venom. However, the autoxidizability of the preparation indicates that the cytochrome has been solubilized in a modified form. A CO-binding pigment can be obtained from mung bean microsomes by digestion with snake venom.

Kasinsky, Harold E.; Shichi, Hitoshi; Hackett, David P.

1966-01-01

218

40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.  

Code of Federal Regulations, 2010 CFR

...Regulations: Particulate matter, Southeast Desert Intrastate Region. 52.228 Section...Regulations: Particulate matter, Southeast Desert Intrastate Region. (a) The following...for particulate matter in the Southeast Desert Intrastate Region. (1) Imperial...

2010-07-01

219

40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.  

Code of Federal Regulations, 2013 CFR

...Regulations: Particulate matter, Southeast Desert Intrastate Region. 52.228 Section...Regulations: Particulate matter, Southeast Desert Intrastate Region. (a) The following...for particulate matter in the Southeast Desert Intrastate Region. (1) Imperial...

2013-07-01

220

40 CFR 52.228 - Regulations: Particulate matter, Southeast Desert Intrastate Region.  

Code of Federal Regulations, 2010 CFR

...Regulations: Particulate matter, Southeast Desert Intrastate Region. 52.228 Section...Regulations: Particulate matter, Southeast Desert Intrastate Region. (a) The following...for particulate matter in the Southeast Desert Intrastate Region. (1) Imperial...

2009-07-01

221

78 FR 78315 - Revision to the Idaho State Implementation Plan; Approval of Fine Particulate Matter Control...  

Federal Register 2010, 2011, 2012, 2013

...fine particulate matter (PM 2.5 ...24-Hour Fine Particulate (PM 2.5 ...Despite the limited nature of this proposed...the cross-state nature of the Logan...Nitrogen dioxide, Particulate matter, Reporting...

2013-12-26

222

40 CFR 63.1357 - Temporary, conditioned exemption from particulate matter and opacity standards.  

Code of Federal Regulations, 2013 CFR

...conditioned exemption from particulate matter and opacity standards. 63.1357 ...conditioned exemption from particulate matter and opacity standards. (a) Subject...condition; (2) The target particulate matter emission level for each test...

2013-07-01

223

30 CFR 57.5060 - Limit on exposure to diesel particulate matter.  

Code of Federal Regulations, 2010 CFR

...false Limit on exposure to diesel particulate matter. 57.5060 Section 57.5060 Mineral Resources...Radiation, Physical Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5060 Limit on...

2009-07-01

224

30 CFR 57.5060 - Limit on exposure to diesel particulate matter.  

Code of Federal Regulations, 2010 CFR

...false Limit on exposure to diesel particulate matter. 57.5060 Section 57.5060 Mineral Resources...Radiation, Physical Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5060 Limit on...

2010-07-01

225

75 FR 30710 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Particulate Matter...  

Federal Register 2010, 2011, 2012, 2013

...The updates were made to the particulate matter standards by adding fine particulate standards and revoking the state's course particulate standards. The State of Wisconsin...would be withdrawn and not take effect. On May 7, 2010, EPA...

2010-06-02

226

Fugitive particulate emission estimates for incinerator ash handling  

Microsoft Academic Search

Fugitive emissions have been identified as a significant source of total suspended particulate (TSP) emissions from some industries. Fugitive emissions of inhalable particulates (particles less than 10 μ equivalent aerodynamic diameter, or PMââ) are less than for TSP, but can be significant in some circumstances. Both are subject to regulation under Federal Prevention of Significant Deterioration (PSD) regulations. Fugitive emissions

R. C. Wells; R. J. Machaver; W. R. Allen

1988-01-01

227

Thermal conductivity measurements of particulate materials 1. A review  

Microsoft Academic Search

Discussion of the thermal conductivity of particulate materials is dispersed over several decades and a wide range of disciplines. In addition, there is some disparity among the reported values. This paper presents a review of the methodology available for the study of thermal conductivity of particulate materials, with an emphasis on low atmospheric pressures, and an assessment of the dependability

Marsha A. Presley; Philip R. Christensen

1997-01-01

228

CONTROL TECHNOLOGIES FOR PARTICULATE AND TAR EMISSIONS FROM COAL CONVERTERS  

EPA Science Inventory

The report gives results of a characterization of solid and tar particulate emissions in raw product gases from several types of coal gasifiers, in terms of their total quantities, chemical composition, and size distribution. Fixed-bed gasifiers produce the smallest particulate l...

229

CONTROLLING PARTICULATE EMISSIONS FROM COAL-FIRED BOILERS  

EPA Science Inventory

The report gives a semi-technical overview of the contribution of particulate matter to the overall U.S. air pollution problem. It also discusses contributions of the Particulate Technology Branch of EPA's Industrial Environmental Research Laboratory at Research Triangle Park, NC...

230

The Relocation of Particulate Contamination During Space Flight  

NASA Technical Reports Server (NTRS)

A computer simulation program to model the redistribution of particulate contaminants on a spacecraft after launch is developed. The component models for particulate adhesion, meteoroid impact, and electrostatic forces are described and intermediate results are presented. The results of a sample calculation show that the recontamination process is important.

Barengoltz, J.; Edgars, D.

1975-01-01

231

Heart rate variability associated with particulate air pollution  

Microsoft Academic Search

Background: Epidemiologic studies have linked fine particulate air pollution with cardiopulmonary mortality, yet underlying biologic mechanisms remain unknown. Changes in heart rate variability (HRV) may reflect changes in cardiac autonomic function and risk of sudden cardiac death. This study evaluated changes in mean heart rate and HRV in human beings associated with changes in exposure to particulate air pollution. Methods:

C. Arden Pope; Richard L. Verrier; Eric G. Lovett; Andrew C. Larson; Mark E. Raizenne; Richard E. Kanner; Joel Schwartz; G. Martin Villegas; Diane R. Gold; Douglas W. Dockery

1999-01-01

232

Behavior of perfluoropolyether in particulate magnetic recording media  

Microsoft Academic Search

In order to achieve the required frictional properties in the particulate media, the adequate amount of surface lubricant is investigated. By using newly-synthesized perfluoropolyethers (PFPEs) in particulate media, the amount of surface lubricant is evaluated by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. It is necessary for friction reduction to have not only large coverage ratio of the outer

Y. Nishida; Y. Hisamichi; H. Kondo

1996-01-01

233

Process for off-gas particulate removal and apparatus therefor  

SciTech Connect

In the event of a breach in the off-gas line of a melter operation requiring closure of the line, a secondary vessel vent line is provided with a particulate collector utilizing atomization for removal of large particulates from the off-gas. The collector receives the gas containing particulates and directs a portion of the gas through outer and inner annular channels. The collector further receives a fluid, such as water, which is directed through the outer channel together with a second portion of the particulate-laden gas. The outer and inner channels have respective ring-like termination apertures concentrically disposed adjacent one another on the outer edge of the downstream side of the particulate collector. Each of the outer and inner channels curves outwardly away from the collector`s centerline in proceeding toward the downstream side of the collector. Gas flow in the outer channel maintains the fluid on the channel`s wall in the form of a ``wavy film,`` while the gas stream from the inner channel shears the fluid film as it exits the outer channel in reducing the fluid to small droplets. Droplets formed by the collector capture particulates in the gas stream by one of three mechanisms: impaction, interception or Brownian diffusion in removing the particulates. The particulate-laden droplets are removed from the fluid stream by a vessel vent condenser or mist eliminator. 4 figs.

Carl, D.E.

1997-10-21

234

Particulate emissions from commercial shipping: Chemical, physical, and optical properties  

Microsoft Academic Search

We characterize particulate emissions on the basis of chemical, physical, and optical properties from commercial vessels. Observations during the Texas Air Quality Study\\/Gulf of Mexico Atmospheric Composition and Climate Study 2006 field campaign provide chemical and physical characteristics including sulfate (SO42?) mass, organic matter (OM) mass, black carbon (BC) mass, particulate matter (PM) mass, number concentrations (condensation nuclei (CN) >

Daniel A. Lack; James J. Corbett; Timothy Onasch; Brian Lerner; Paola Massoli; Patricia K. Quinn; Timothy S. Bates; Derek Coffman; Berko Sierau; Scott Herndon; James Allan; Tahllee Baynard; Edward Lovejoy; A. R. Ravishankara; Eric Williams

2009-01-01

235

Distribution of toxic and radiation components in air particulates  

Microsoft Academic Search

The concentrations of several toxic heavy metals and volatile organic compounds (VOCs) in various types of Hungarian fly-ash fine particulates were investigated by means of instrumental neutron activation analysis, X-ray fluorescence analysis and gas chromatography, coupled with mass spectrometry. Within a power station, particulate samples were taken from the boiler zone (BO), from the electrostatic dust filter chamber (FI) and

H. Rausch; I. L. Sziklai; J. Borossay; K. Torkos; T. Rikker; É. Zemplén-Papp

1995-01-01

236

Method for immobilizing particulate materials in a packed bed  

DOEpatents

The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

Even, Jr., William R. (Livermore, CA); Guthrie, Stephen E. (Livermore, CA); Raber, Thomas N. (Livermore, CA); Wally, Karl (Lafayette, CA); Whinnery, LeRoy L. (Livermore, CA); Zifer, Thomas (Manteca, CA)

1999-01-01

237

Method for immobilizing particulate materials in a packed bed  

DOEpatents

The present invention pertains generally to immobilizing particulate matter contained in a packed bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that (a) the particulate retains its essential chemical nature, (b) the local movement of the particulate particles is not unduly restricted, (c) bulk powder migration and is prevented, (d) physical and chemical access to the particulate is unchanged over time, and (e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of an individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport. 4 figs.

Even, W.R. Jr.; Guthrie, S.E.; Raber, T.N.; Wally, K.; Whinnery, L.L.; Zifer, T.

1999-02-02

238

Removal of SOx, NOx, and particulate from combusted carbonaceous fuels  

Microsoft Academic Search

The invention is a method for removing sulfur oxides, nitrogen oxides and particulate from the products of combusted carbonaceous fuels. Sulfur oxides, nitrogen oxides and particulate are currently discharged to the atmosphere as flue gas in quantities highly detrimental to the environment. Potassium compounds, as are found in agricultural grade potash, are dispersed throughout the combustion products at the exit

Dayen

1985-01-01

239

ASSESSMENT OF DIESEL PARTICULATE CONTROL: DIRECT AND CATALYTIC OXIDATION  

EPA Science Inventory

The report discusses the technology and potential for disposal of diesel particulate by oxidation. Relevant properties of typical diesel particulate are given; note is taken of the small size (on the order of 0.1 micrometer diameter) and the presence of a portion extractable with...

240

Method for removing particulate matter from a gas stream  

DOEpatents

Particulate matter is removed from a stream of pressurized gas by directing the stream of gas upwardly through a bed of porous material, the porous bed being held in an open ended container and at least partially submerged in liquid. The passage of the gas through the porous bed sets up a circulation in the liquid which cleans the particulate matter from the bed.

Postma, Arlin K. (Benton City, WA)

1984-01-01

241

Particulate metals contamination in the Kishon River estuary, Israel  

Microsoft Academic Search

Suspended particulate matter (SPM) collected along the axis of the Kishon River, its estuary and Haifa Bay were analysed for trace metal concentrations together with measurements of water density, pH and dissolved oxygen. The concentrations of particulate Cd, Zn and Cu generally increased from the upper Kishon system (upstream from Tzipori-Kishon Junction) downstream and decreased from the Kishon Harbour seaward,

Barak Herut; Nurit Kress

1997-01-01

242

Exposure to particulate hexavalent chromium exacerbates allergic asthma pathology  

SciTech Connect

Airborne hexavalent chromate, Cr(VI), has been identified by the Environmental Protection Agency as a possible health threat in urban areas, due to the carcinogenic potential of some of its forms. Particulate chromates are produced in many different industrial settings, with high levels of aerosolized forms historically documented. Along with an increased risk of lung cancer, a high incidence of allergic asthma has been reported in workers exposed to certain inhaled particulate Cr(VI) compounds. However, a direct causal association between Cr(VI) and allergic asthma has not been established. We recently showed that inhaled particulate Cr(VI) induces an innate neutrophilic inflammatory response in BALB/c mice. In the current studies we investigated how the inflammation induced by inhaled particulate Cr(VI) might alter the pathology of an allergic asthmatic response. We used a well-established mouse model of allergic asthma. Groups of ovalbumin protein (OVA)-primed mice were challenged either with OVA alone, or with a combination of OVA and particulate zinc chromate, and various parameters associated with asthmatic responses were measured. Co-exposure to particulate Cr(VI) and OVA mediated a mixed form of asthma in which both eosinophils and neutrophils are present in airways, tissue pathology is markedly exacerbated, and airway hyperresponsiveness is significantly increased. Taken together these findings suggest that inhalation of particulate forms of Cr(VI) may augment the severity of ongoing allergic asthma, as well as alter its phenotype. Such findings may have implications for asthmatics in settings in which airborne particulate Cr(VI) compounds are present at high levels. -- Highlights: ? Allergic asthma correlated with exposure to certain inhaled particulate chromates. ? Direct causal association between Cr(VI) and allergic asthma not established. ? Cr exacerbated pathology and airway hyperresponsiveness in an OVA-challenged mouse. ? Particulate Cr(VI) may augment severity and alter phenotype of ongoing allergic asthma.

Schneider, Brent C. [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States) [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States); Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States); Constant, Stephanie L. [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States)] [Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington, DC 20037 (United States); Patierno, Steven R. [Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States) [Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States); GW Cancer Institute, The George Washington University, Washington, DC 20037 (United States); Jurjus, Rosalyn A. [Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037 (United States)] [Department of Anatomy and Regenerative Biology, The George Washington University, Washington, DC 20037 (United States); Ceryak, Susan M., E-mail: phmsmc@gwumc.edu [Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037 (United States)

2012-02-15

243

RELATIONSHIPS BETWEEN TOTAL SUSPENDED PARTICULATE, SULFATE, AND RESPIRABLE SUSPENDED PARTICULATE CONCENTRATIONS. ANALYSIS OF DATA COLLECTED IN NEW YORK CITY  

EPA Science Inventory

Two years of data for daily total suspended particulate, sulfate, and respirable suspended particulate concentrations measured at four stations in the New York City area are statistically analyzed. To show the variability of each pollutant data set, the mean, median, and 16th and...

244

The vega particulate shell: comets or asteroids?  

PubMed

The Infrared Astronomical Satellite (IRAS) science team has discovered a shell of particulate material around the star Vega. At the mean distance and temperature of the shell, the expected condensation products from a protostellar nebula would be dominated by frozen volatiles, in particular water ice. It is not possible to discriminate between dirty ice and silicate materials in the Vega shell on the basis of the IRAS data. The Vega shell is probably a ring of cometary bodies with an estimated minimum mass of 15 earth masses, analogous to one that has been hypothesized for the solar system. A possible hot inner shell around Vega may be an asteroid-like belt of material a few astronomical units from the star. PMID:17731997

Weissman, P R

1984-06-01

245

Permanent disposal of radioactive particulate waste  

SciTech Connect

A system for storage and encapsulation of radioactive particulate waste, is described comprising: a cartridge having a liquid impervious casing enclosing a waster storage region, a ferromagnetic waste storage matrix housed in the cartridge and occupying at least a major portion of the waste storage region, and an inlet conduit and at least one outlet conduit projecting from the cartridge and communicating with the waste storage region; means for establishing a magnetic field in the matrix; fluid handling means including a source of liquid containing the radioactive waste to be stored in the cartridge, a source of encapsulating material, and a receptacle for receiving flushing water; cartridge filling means including conduits releasably couplable to the conduits associated with the cartridge; and fluid flow control means including remotely controllable valves connected between the fluid handling means and the cartridge filling means.

Troy, M.

1988-04-19

246

Quasi-specular reflection from particulate media  

NASA Astrophysics Data System (ADS)

Specular reflection is known to play an important role in many fields of scattering applications, e.g., in remote sensing, computer graphics, optimization of visual appearance of industrial products. Usually it can be assumed that the object has a solid surface and that the properties of the surface will dictate the behavior of the specular component. In this study I will show that media consisting of wavelength-sized particles can also have a quasi-specular reflection in cases where there are ordered structure in the media. I will also show that the quasi-specular reflection in particulate media is more than just a surface effect, and planar particle arrangement below the very surface can give rise to quasi-specular reflection. This study shows that the quasi-specular reflection may contribute in some cases in the backscattering direction, together with coherent backscattering and shadow-hiding effects.

Penttilä, Antti

2013-12-01

247

Infrared spectral behavior of fine particulate solids  

USGS Publications Warehouse

Transmission and emission spectra of clouds and layers of fine particulate samples of quartz, magnesium oxide, and aluminum oxide in the 6.5-35-??m wavelength range are presented. They demonstrate that the behavior of layers of particles constitutes a good analogue for a cloud of particles; that individual micrometer-sized particles emit most where they absorb most; that as the size of the particle is increased, the emission features reverse polarity and the spectrum approaches that of one obtained from a polished plate; and that as the particle layer-thickness increases, radiative interaction becomes increasingly important so that the emission maximum shifts from the strongest to weaker features, or produces a maximum at the Christiansen wavelength.

Hunt, G. R.

1976-01-01

248

Particulate Emission Abatement for Krakow Boilerhouses  

SciTech Connect

Environmental cleanup and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland`s primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are numerous uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in the reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy.

NONE

1998-09-14

249

Elemental composition of arctic particulate matter  

NASA Technical Reports Server (NTRS)

Measurements were made of the elemental composition of particulate matter collected in flights in the Arctic in spring 1983 as part of the Arctic Gas and Aerosol Sampling Program (AGASP). Ten samples of size-selected particles were analyzed by four nondestructive techniques at Davis. Concentrations were determined for H, C, N, and O by Forward Alpha Scattering Techniques (FAST) and for elements heavier than fluorine by Particle Induced X-ray Emission (PIXE). Total mass was measured gravimetrically, and optical absorption was measured using the Laser Integrating Plate Method (LIPM). Results of the analyses show dramatic differences in concentrations and elemental ratios from the Alaskan Arctic to the Norwegian Arctic, with indications of wood smoke and sulfuric acid in the arctic atmosphere.

Cahill, T. A.; Eldred, R. A.

1984-01-01

250

Overlap zoned electrically heated particulate filter  

DOEpatents

A system includes a particulate matter (PM) filter that includes an upstream end for receiving exhaust gas and a downstream end. A zoned heater is arranged spaced from the upstream end and comprises N zones, where N is an integer greater than one, wherein each of the N zones comprises M sub-zones, where M is an integer greater than or equal to one, and wherein the N zones and the M sub-zones are arranged in P layers, where P is an integer greater than one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates non-selected ones of the N zones.

Gonze, Eugene V [Pinckney, MI; Chapman, Mark R [Brighton, MI

2011-07-19

251

The Vega particulate shell - Comets or asteroids?  

NASA Technical Reports Server (NTRS)

The Infrared Astronomical Satellite (IRAS) science team has discovered a shell of particulate material around the star Vega. At the mean distance and temperature of the shell, the expected condensation products from a protostellar nebula would be dominated by frozen volatiles, in particular water ice. It is not possible to discriminate between dirty ice and silicate materials in the Vega shell on the basis of the IRAS data. The Vega shell is probably a ring of cometary bodies with an estimated minimum mass of 15 earth masses, analogous to one that has been hypothesized for the solar system. A possible hot inner shell around Vega may be an asteroid-like belt of material a few astronomical units from the star.

Weissman, P. R.

1984-01-01

252

Supercritical water oxidation of solid particulates  

SciTech Connect

In the application of supercritical water oxidation (SCWO) to the treatment of aqueous solid wastes, particle size will be an important processing parameter. The particle size will impact feed preparation requirements such as slurry concentration, pumping requirements, and, in terms of the destruction of the solid particles, rate of reaction and reactor size. To address these issues, an experimental research program was undertaken to evaluate the effect of particle size on the reaction kinetics in SCWO of solid particulates (wheat straw and cellulose particles in this case). The experiments also included evaluation of the effects of temperature, pressure, and agitation rate. A two-step reaction mechanism was revealed, with a very rapid initial dissolution period followed by a longer particle reaction period. Empirically based mathematical relationships were developed that can be used for SCWO system design.

Pisharody, S.A.; Fisher, J.W. [NASA Ames Research Center, Moffett Field, CA (United States)] [NASA Ames Research Center, Moffett Field, CA (United States); Abraham, M.A. [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering] [Univ. of Tulsa, OK (United States). Dept. of Chemical Engineering

1996-12-01

253

Particulate contamination removal from wafers using plasmas and mechanical agitation  

DOEpatents

Particulate contamination removal from wafers using plasmas and mechanical agitation. The present invention includes the use of plasmas with mechanical agitation for removing particulate matter from the surface of a wafer. The apparatus hereof comprises a mechanical activator, at least one conducting contact pin for transferring the vibration from the activator to the wafer, clamp fingers that maintain the wafer's position, and means for generating a plasma in the vicinity of the surface of the wafer, all parts of the cleaning apparatus except the mechanical activator and part of the contact pin being contained inside the processing chamber. By exposing a wafer to a plasma and providing motion thereto in a direction perpendicular to its surface, the bonding between the particulate matter and the surface may be overcome. Once free of the wafer surface, the particulates become charged by electrons from the plasma and are drawn into the plasma by attractive forces which keep them from redepositing. The introduction of a flowing gas through the plasma sweeps the particulates away from the wafer and out of the plasma. The entire surface is cleaned during one cleaning step. The use of an rf plasma to accomplish the particulate removal was found to remove more than 90% of the particulates.

Selwyn, Gary S. (Los Alamos, NM)

1998-01-01

254

Regenerative cyclone-type air/particulate concentrator and collector  

SciTech Connect

A cyclone-type particulate collector and concentrator is provided wherein the outlet tube is provided with a conical concentrator having its sidewalls formed of a plurality of tapered, spaced, nested, generally u-shaped and cross-section vaned members between which the gas entering the outlet tube must pass in flowing to the outlet end of the outlet tube. A portion of the sidewall of the outlet tube of the cyclone-type particulate collector is provided with a gate to act as a particulate skimmer which opens into the gas inlet volute for recirculation of the skimmed particles.

Haynes, W.R.; Truhan, A.

1981-04-07

255

A laser particulate spectrometer for a space simulation facility  

NASA Technical Reports Server (NTRS)

A laser particulate spectrometer (LPS) system was developed to measure the size and speed distributions of particulate contaminants. Detection of the particulates is achieved by means of light scattering and extinction effects using a single laser beam to cover a size range of 0.8 to 275 microns diameter and a speed range of 0.2 to 20 meters/second. The LPS system was designed to operate in the high-vacuum environment of a space simulation chamber with cold shroud temperatures ranging from 77 to 300 K.

Schmitt, R. J.; Boyd, B. A.; Linford, R. M. F.; Richmond, R. G.

1975-01-01

256

Particulate Emission Abatement for Krakow Boilerhouses.  

SciTech Connect

Environmental clean-up and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland`s primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are more than 2,000 uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in the reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy. It utilizes a highly efficient collector, which functions on the principle of inertial separation. The system is able to control fine particulate matter, as in the PMIO regulations, which limit the emission of dust particles below 10 microns in diameter. Its dust removal performance has been shown to be comparable to that of a medium-efficiency electrostatic precipitator (ESP). Yet, its cost is substantially lower than that of either an ESP or fabric filter. While the Core Separator achieves high efficiency, its power consumption is just slightly higher than that of a cyclone. It functions dry and without the aid of energy-consuming enhancements. It is simple, reliable, and unlike the ESP and fabric filter, easy to maintain. This combination of features make it ideal for the small boiler market in the City of Krakow. A highly qualified team has been assembled to execute this project. LSR Technologies, Inc., a technology-based company located in Acton, Massachusetts, is the developer of the Core Separator and holder of its patent rights. LSR has sold several of these units in the U.S. and Europe. Ecolnstal, a leading supplier of environmental equipment in Poland, is licensed to sell the Core Separator, and will support LSR as a subcontractor. The Polish Foundation for Energy Efficiency (FEWE), located in Katowice, is a consulting organization with extensive expertise in the Polish economy and natural environment. FEWE is also be a subcontractor to LSR. This project will be divided into three major phases. Phase 1 is called `Infrastructure Studies` and includes business planning, and site-selection of a full-scale Core Separator Demonstration Unit. Phase 2, called `Commercial Development,` includes the first Demonstration Unit in a local boilerhouse, followed by several Core Separator installations collecting flyash from different Polish coals. Also, a manufacturing facility is to be equipped to accommodate the projected sales volume. If the goals of this project are met and the Core Separator can be successfully marketed, there is a potential to significantly reduce particulate emissions in Krakow.

Hucko, R.E.

1997-04-30

257

Particulate hot gas stream cleanup technical issues  

SciTech Connect

This is the eleventh in a series of quarterly reports describing the activities performed under Contract No. DE-AC21-94MC31160. Analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance address aspects of filter operation that are apparently linked to the characteristics of the collected ash or the performance of the ceramic bed filter elements. Task 1 is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APFS) and to relate these ash properties to the operation and performance of these filters. Task 2 concerns testing and failure analysis of ceramic filter elements. Under Task 1 during the past quarter, analyses were completed on samples obtained during a site visit to the Power Systems Development Facility (PSDF). Analyses are in progress on ash samples from the Advanced Particulate Filter (APF) at the Pressurized Fluidized-Bed Combustor (PFBC) that was in operation at Tidd and ash samples from the Pressurized Circulating Fluid Bed (PCFB) system located at Karhula, Finland. An additional analysis was performed on a particulate sample from the Transport Reactor Demonstration Unit (TRDU) located at the University of North Dakota Energy and Environmental Research Center. A manuscript and poster were prepared for presentation at the Advanced Coal-Based Power and Environmental Systems `97 Conference scheduled for July 22 - 24, 1997. A summary of recent project work covering the mechanisms responsible for ash deposit consolidation and ash bridging in APF`s collecting PFB ash was prepared and presented at FETC-MGN in early July. The material presented at that meeting is included in the manuscript prepared for the Contractor`s Conference and also in this report. Task 2 work during the past quarter included mechanical testing and microstructural examination of Schumacher FT20 and Pall 326 as- manufactured, after 540 hr in service at Karhula, and after 1166 hr in service at Karhula. Key test results showed that property degradation occurred during service at Karhula but less degradation than was seen in Schumacher F40 and Pall 442T. Creep continues to be observed in tests at 1600 `F and above and was observed at 1562 `F in service at Karhula. Microstructural evaluations of FT20 and 326 materials have shown that the behavior of these materials is controlled by the ceramic binders and that the binders are still glass limited. These results were presented in a poster session and a paper written for the Advanced Coal-Based Power and Environmental Systems `97 Conference.

NONE

1998-09-01

258

Particulate oxidative burden associated with firework activity.  

PubMed

Firework events are capable of inducing particulate matter (PM) episodes that lead to exceedances of regulatory limit values. As short-term peaks in ambient PM concentration have been associated with negative impacts on respiratory and cardiovascular health, we performed a detailed study of the consequences of firework events in London on ambient air quality and PM composition. These changes were further related to the oxidative activity of daily PM samples by assessing their capacity to drive the oxidation of physiologically important lung antioxidants including ascorbate, glutathione and urate (oxidative potential, OP). Twenty-four hour ambient PM samples were collected at the Marylebone Road sampling site in Central London over a three week period, including two major festivals celebrated with pyrotechnic events: Guy Fawkes Night and Diwali. Pyrotechnic combustion events were characterized by increased gas phase pollutants levels (NO(x) and SO(2)), elevated PM mass concentrations, and trace metal concentrations (specifically Sr, Mg, K, Ba, and Pb). Relationships between NO(x), benzene, and PM(10) were used to apportion firework and traffic source fractions. A positive significant relationship was found between PM oxidative burden and individual trace metals associated with each of these apportioned source fractions. The level of exposure to each source fraction was significantly associated with the total OP. The firework contribution to PM total OP, on a unit mass basis, was greater than that associated with traffic sources: a 1 ?g elevation in firework and traffic PM fraction concentration was associated with a 6.5 ± 1.5 OP(T) ?g(-1) and 5.2 ± 1.4 OP(T) ?g(-1) increase, respectively. In the case of glutathione depletion, firework particulate OP (3.5 ± 0.8 OP(GSH) ?g(-1)) considerably exceeded that due to traffic particles (2.2 ± 0.8 OP(GSH) ?g(-1)). Therefore, in light of the elevated PM concentrations caused by firework activity and the increased oxidative activity of this PM source, there is value in examining if firework derived PM is related to acute respiratory outcomes. PMID:20886897

Godri, Krystal J; Green, David C; Fuller, Gary W; Dall'Osto, Manuel; Beddows, David C; Kelly, Frank J; Harrison, Roy M; Mudway, Ian S

2010-11-01

259

Study of the adequacy of air monitoring. Part II. Inhalable particulates. Draft report  

SciTech Connect

This is a study of the current status of inhalable particulate monitoring, the need for future monitoring, and of the status of a National Ambient Air Quality Standard for inhalable particulates. The study asked about the extent of the data base available on particulates, the quality of current monitoring techniques, a size-specific standard for particulates, and possible effects of a standard.

Patterson, R.M.; Cavanagh, L.A.; Ruff, R.E.

1980-12-01

260

Impact of particulates and SOâ from coal-fired power plants on acid rain  

Microsoft Academic Search

Sulfur dioxide and acid rain trends are documented and mapped. The size and composition of particulate emissions are evaluated. The interactions between particulates and sulfur-containing gases are identified as absorption-oxidation and direct catalytic oxidation of SOâ by particulates. Each of these reaction types is discussed in detail. The effect of particulate emission control devices on the formation of acid rain

K. P. Ananth; J. B. Galeski; L. J. Shannon; F. I. Honea; D. Drehmel

1977-01-01

261

40 CFR 52.2059 - Control strategy: Particulate matter.  

Code of Federal Regulations, 2013 CFR

...as of August 25, 2008, the Harrisburg-Lebanon-Carlisle, Pennsylvania...ambient air quality data, the Harrisburg-Lebanon-Carlisle-York...Philadelphia-Wilmington, PA-NJ-DE nonattainment area...Philadelphia-Wilmington, PA-NJ-DE fine particulate...

2013-07-01

262

Relationship between Personal Exposures and Ambient Concentrations of Particulate Matter.  

National Technical Information Service (NTIS)

It is established that personally monitored particulate matter (PM) is poorly correlated with ambient concentrations of PM. This observation is inconsistent with epidemiology studies relating ambient PM to mortality. This paper reviews in depth the relati...

D. T. Mage T. J. Buckley

1995-01-01

263

40 CFR 60.132 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...discharge into the atmosphere from a reverberatory furnace any gases which: (1) Contain particulate...cause the discharge into the atmosphere from any blast (cupola) or electric furnace any gases which exhibit 10 percent opacity or...

2013-07-01

264

40 CFR 60.182 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...operator subject to the provisions of this subpart shall cause to be discharged into the atmosphere from any blast furnace, dross reverberatory furnace, or sintering machine discharge end any gases which contain particulate matter in excess of 50...

2013-07-01

265

40 CFR 60.122 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...cause the discharge into the atmosphere from a blast (cupola) or reverberatory furnace any gases which: (1) Contain particulate...the discharge into the atmosphere from any pot furnace any gases which exhibit 10 percent opacity...

2013-07-01

266

[Health risks of airborne particulate matter in children].  

PubMed

The chemical composition of particulate matter can be very diverse, comprising a range of toxic compounds. Exposure to airborne particulate matter has been considered a substantial health risk for two decades now. There is no scientific evidence for a safe exposure limit. Therefore, current exposure levels across Europe are reason for concern. Exposure to particulate matter in adults may cause severe respiratory and cardiovascular disease. There is abundant epidemiological evidence that children, and younger children in particular, are more susceptible to the adverse effects of particular matter on health than adults. Short term exposure of children may already cause respiratory symptoms and allergic reactions. Environmental health policies reducing risks of exposure to particulate matter in children are recommended. PMID:24128602

Kleinjans, Jos C S

2013-01-01

267

Cost-effectiveness of diesel fuel modifications for particulate control  

SciTech Connect

A methodology for assessing the cost-effectiveness of diesel fuel modification as a particulate control technique is presented. The cost-effectiveness of three diesel fuel modification scenarios have been calculated and compared with the cost-effectiveness of alternative particulate control strategies. The three fuel modifications which were evaluated are: reduced sulfur content; reduced sulfur content in conjunction with reduced aromatics content; and reduced sulfur and aromatics contents in conjunction with reduced ninety percent distillation temperature. Sulfur content is the only fuel property which can be altered to affect diesel-derived sulfate particulate levels in the atmosphere. The cost-effectiveness of fuel sulfur reduction is compared to the cost-effectiveness of control measures for other sources of sulfate particulate.

Ingham, M.C.; Warden, R.B.

1987-01-01

268

Plasma Aftertreatment for Simultaneous Control of NOx and Particulates  

SciTech Connect

Plasma reactors can be operated as a particulate trap or as a NO{sub x} converter. The soluble organic fraction (SOF) of the trapped particulates can be utilized for the oxidation of NO to NO{sub 2}. The NO{sub 2} can then be used to non-thermally oxidize the carbon fraction of the particulates. This paper examines the energy density required for oxidation of the SOF hydrocarbons and the fate of NO{sub 2} during the oxidation of the particulate carbon. The energy density required for complete oxidation of the SOF hydrocarbons is shown to be unacceptably large. The reaction of NO{sub 2} with carbon is shown to lead mainly to backconversion of NO{sub 2} to NO. These results suggest that the use of a catalyst in combination with the plasma will be required to efficiently reduce the NO{sub x} and oxidize the SOF hydrocarbons.

Penetrante, B.M.; Brusasco, R.M.; Merritt, B.T.; Pitz, W.J.; Vogtlin, G.E.

1999-10-28

269

Three-Dimensional Characterization of Polydisperse Particulate Composites from Microtomography.  

National Technical Information Service (NTIS)

This work contributes to a larger effort to analyze the mechanical and transport properties of polydisperse particulate composites. In order to improve the understanding of the morphology of such systems, specimens are analyzed from tomographic images. Th...

S. Atkinson

2011-01-01

270

AMBIENT PARTICULATE MATTER DECREASED IN HUMAN ALVEOLAR MACHROPHAGE CYTOKINE RELEASE  

EPA Science Inventory

Human exposure to ambient airborne particulate matter (PM) is associated with cardiopulmonary mortality and morbidity, including increased hospitalizations for lung infection. Normal lung immune responses to bacterial infection include alveolar macrophage cytokine production and...

271

COMPARISON OF METHODS FOR MEASURING CONCENTRATIONS OF SEMIVOLATILE PARTICULATE MATTER  

EPA Science Inventory

The paper gives results of a comparison of methods for measuring concentrations of semivolatile particulate matter (PM) from indoor-environment, small, combustion sources. Particle concentration measurements were compared for methods using filters and a small electrostatic precip...

272

Design, Fabrication, and Installation of a Particulate Aerodynamic Test Facility.  

National Technical Information Service (NTIS)

The report presents the trade-offs and design considerations, component selection criteria, and final design details for a particulate aerodynamic test facility. The design meets a range of performance specifications for the test gas, including test secti...

D. D. Blann K. A. Green L. W. Anderson

1974-01-01

273

EFFECTS OF PARTICULATE MATTER (PM) ON CARDIAC CELLS  

EPA Science Inventory

Although epidemiology studies, clinical studies, and animal studies indicate that particulate matter (PM) can affect cardiac function, there is no real understanding of the underlying cellular, biochemical, and molecular processes response for PM-induced cardiac dysfunction. It i...

274

Mechanisms of Particulate Toxicity: Health Effects in Susceptible Humans.  

National Technical Information Service (NTIS)

Particulate air pollution is an issue of global health importance, being a major component of air pollution, and having been associated with increased human cardiorespiratory morbidity and mortality. Individuals with asthma could be particularly susceptib...

C. Solomon J. R. Balmes K. Power L. Miller

2004-01-01

275

Characterizaiton of Particulate Emissions from Municipal Wastewater Sludge Incinerators.  

National Technical Information Service (NTIS)

Particulate emissions from a group of municipal sludge incinerators with multiple-hearth furnaces, one with a fluidized-bed furnace were characterized. Three plants operated at or near autogenous burning conditions. Chemical element composition was determ...

R. L. Bennett K. T. Knapp

1982-01-01

276

MULTIWAVELENGTH TRANSMISSOMETER FOR MEASURING MASS CONCENTRATION OF PARTICULATE EMISSIONS  

EPA Science Inventory

A multiwavelength transmissometer potentially capable of making near-real-time measurements of particulate mass concentration in industrial stacks was developed. A computer program is employed to interpret the transmissometer data and translate the results into mass concentration...

277

40 CFR 60.272a - Standard for particulate matter.  

Code of Federal Regulations, 2010 CFR

...FOR NEW STATIONARY SOURCES Standards of Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After August 17, 1983 § 60.272a Standard for particulate matter. (a) On...

2010-07-01

278

Mechanical Properties of Particulate Reinforced Aluminium Alloy Matrix Composite  

NASA Astrophysics Data System (ADS)

This paper discusses the mechanical properties of Titanium Carbide (TiC) particulate reinforced aluminium-silicon alloy matrix composite. TiC particulate reinforced LM6 alloy matrix composites were fabricated by carbon dioxide sand molding process with different particulate weight fraction. Tensile strength, hardness and microstructure studies were conducted to determine the maximum load, tensile strength, modulus of elasticity and fracture surface analysis have been performed to characterize the morphological aspects of the test samples after tensile testing. Hardness values are measured for the TiC reinforced LM6 alloy composites and it has been found that it gradually increases with increased addition of the reinforcement phase. The tensile strength of the composites increased with the increase percentage of TiC particulate.

Sayuti, M.; Sulaiman, S.; Baharudin, B. T. H. T.; Arifin, M. K. A.; Suraya, S.; Vijayaram, T. R.

2011-01-01

279

Particulate Air Contamination in Puerto Rico: A Student Involvement Project.  

ERIC Educational Resources Information Center

Describes a research project undertaken by physics undergraduate students to monitor particulate air contamination in Ponce, Puerto Rico, and to determine the meteorological factors which contribute to it. (GA)

Eckert, Richard R.

1979-01-01

280

Health effects of particulate air pollution: time for reassessment?  

PubMed Central

Numerous studies have observed health effects of particulate air pollution. Compared to early studies that focused on severe air pollution episodes, recent studies are more relevant to understanding health effects of pollution at levels common to contemporary cities in the developed world. We review recent epidemiologic studies that evaluated health effects of particulate air pollution and conclude that respirable particulate air pollution is likely an important contributing factor to respiratory disease. Observed health effects include increased respiratory symptoms, decreased lung function, increased hospitalizations and other health care visits for respiratory and cardiovascular disease, increased respiratory morbidity as measured by absenteeism from work or school or other restrictions in activity, and increased cardiopulmonary disease mortality. These health effects are observed at levels common to many U.S. cities including levels below current U.S. National Ambient Air Quality Standards for particulate air pollution. Images Figure 1.

Pope, C A; Bates, D V; Raizenne, M E

1995-01-01

281

Particulate debris collected during carotid stenting: are we missing something?  

PubMed

Particulate and histopathologic examination of atherosclerotic material collected during carotid artery stenting is presented, illustrating the limitations of current knowledge regarding the use of distal protection devices (DPD) during this novel vascular intervention. PMID:17126427

Cheng, W Y; Stephens, M; Lin, B P C; Lowe, H C; McMahon, A C

2007-07-10

282

DOSE CONCENTRATED COARSE PARTICULATE MATTER EXPOSURE PRODUCE ADVERSE HEALTH EFFECTS?  

EPA Science Inventory

The potential for experiencing adverse health effects from particulate matter (PM) exposure is an important public health issue. Mortality associations have generally been shown to be stronger for fine PM (...

283

CONTINUOUS MEASUREMENT OF DIESEL PARTICULATE EMISSIONS (JOURNAL VERSION)  

EPA Science Inventory

Evaluation of emerging diesel particulate emissions control technology will require analytical procedures capable of continuous measurement of transient organic and elemental carbon emissions. Procedures based on the flame ionization properties of organic carbon and the opacity o...

284

SAMPLING AND ANALYTICAL METHODOLOGY FOR ATMOSPHERIC PARTICULATE NITRATES  

EPA Science Inventory

Environmental conditions that affect atmospheric particulate nitrate sampling were identified, and improved sampling and analytical procedures were developed. Evaluation of potential sources of error in high volume nitrate sampling showed that artifact nitrate formation on common...

285

40 CFR 230.21 - Suspended particulates/turbidity.  

Code of Federal Regulations, 2013 CFR

...suspended in the water column for variable periods of time as a result of such factors as agitation of the water mass, particulate specific gravity, particle shape, and physical and chemical properties of particle surfaces. (b) Possible...

2013-07-01

286

Microscopic Particulate Analysis (MPA) for Filtration Plant Optimization.  

National Technical Information Service (NTIS)

Performance of water treatment plants can be evaluated by a number of methods, including turbidity, particle counts, and Microscopic Particulate Analysis (MPA). MPA, including particle sizing, is performed on drinking water systems where some form of trea...

S. Harris C. Hancock J. Vasconcelos

1996-01-01

287

ULTRAFINE PARTICULATE MATTER EXPOSURE AUGMENTS ISCHEMIA REPERFUSION INJURY IN MICE  

EPA Science Inventory

Epidemiological studies have linked ambient particulate matter (PM) levels to an increased incidence of adverse cardiovascular events. Yet little is definitively known about the mechanisms accounting for the cardiovascular events associated with PM-exposure. The goal of this stud...

288

ULTRAFINE PARTICULATE MATTER EXPOSURE AUGMENTS ISCHEMIA REPERFUSION INJURY IN MICE  

EPA Science Inventory

Epidemiological studies have linked ambient particulate matter (PM) levels to an increased incidence of adverse cardiovascular events. Yet little is definitively known about the mechanisms accounting for the cardiovascular events associated with PM exposure. The goal of thi...

289

40 CFR 60.102 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...fluid catalytic cracking unit catalyst regenerator that is subject to the requirements...fluid catalytic cracking unit catalyst regenerator will be operated, or 180 days after...fluid catalytic cracking unit catalyst regenerator: (1) Particulate matter in...

2013-07-01

290

Measurements of Particulates in Solid Propellant Rocket Motors.  

National Technical Information Service (NTIS)

An investigation has been conducted to develop techniques for obtaining quantitative data that can be used to relate solid rocket propellant composition and operating environment to the behavior of solid particulates within the grain port and exhaust nozz...

A. Kertadidjaja K. G. Horton M. G. Keith R. K. Harris T. D. Edwards

1987-01-01

291

AIR QUALITY CRITERIA FOR PARTICULATE MATTER, VOLUMES I-III  

EPA Science Inventory

There is no abstract available for these documents. If further information is requested, please refer to the bibliographic citation and contact the Technical Information Staff at the number listed below. Air Quality Criteria for Particulate Matter, Volume I - EP...

292

CHARACTERISTICS, DEPOSITION AND FATE OF INHALED PARTICULATE MATTER  

EPA Science Inventory

Accurate estimates of absorption and fate for particulate matter in the respiratory track are difficult because of complexities in particle composition and morphology. Several deficiencies in information further complicate the ability to make accurate estimates. Available models ...

293

JV Task 95-Particulate Control Consulting for Minnesota Ore Operations  

SciTech Connect

The purpose of the project was to assist U.S. Steel in the evaluation, selection, planning, design, and testing of potential approaches to help meet U.S. Steel's goal for low-particulate matter emissions and regulatory compliance. The energy-intensive process for producing iron pellets includes treating the pellets in high-temperature kilns in which the iron is converted from magnetite to hematite. The kilns can be fired with either natural gas or a combination of gas and coal or biomass fuel and are equipped with wet venturi scrubbers for particulate control. Particulate measurements at the inlet and outlet of the scrubbers and analysis of size-fractionated particulate samples led to an understanding of the effect of process variables on the measured emissions and an approach to meet regulatory compliance.

Stanley Miller

2008-10-31

294

Particulate Control Highlights: Research on Electrostatic Precipitator Technology.  

National Technical Information Service (NTIS)

The report gives highlights of a major EPA research program on electrostatic precipitator (ESP) technology, directed toward improving the performance of ESPs in controlling industrial particulate emissions, notably fly ash from coal combustion in electric...

S. Oglesby G. Nichols

1977-01-01

295

Atmospheric Oxidative Chemistry of Organic Particulate Emissions from Fuel Combustion.  

National Technical Information Service (NTIS)

Construction and characterization of the University of Vermont Environmental Chamber (UVMEC) were completed in this last phase of the project. The primary function of the UVMEC is to enable tropospheric particulate formation and aging studies to be perfor...

G. Petrucci, S. Geddews

2011-01-01

296

PARTICULATE MATTER CONCENTRATIONS IN NON-RESIDENTIAL MICROENVIRONMENTS  

EPA Science Inventory

Exposures to airborne particulate matter (PM) have long been associated with increases in both acute and chronic human health effects. Traditionally, research and regulations have focused on outdoor air pollution. However, human activity pattern studies show that people are ind...

297

Particulate Loads Caused by Wind Erosion in the Great Plains  

ERIC Educational Resources Information Center

In this paper the annual flux of suspended particulates caused by wind erosion in the Great Plains is estimated. This study demonstrated that climate causes wide variations in air pollution from wind erosion. (BT)

Hagen, Lawrence J.; Woodruff, Neil P.

1975-01-01

298

Recent advances in magnetostrictive particulate composite technology  

NASA Astrophysics Data System (ADS)

Recently, there have been significant advances in using magnetostrictive particles in a polymer matrix; finding uses in many applications, both as an active transducer and a passive damper. Termed magnetostrictive particulate composites (MPC), the material provides capabilities identical or superior to the monolithic material. Fortis Technologies has been pursuing improvements in the application and fabrication of this innovative material. The MPC technology provides a passive, broadband, large temperature range, high stiffness, dampling material to be used where current technologies fall short. Damping applications of this technology include sporting goods, power/hand tools, space launch and satellite design, noise abatement and vibration isolation. Energy absorption of the composites has been measured and is approaching that of the monolithic material. The material can also be actively controlled by a magnetic field, producing a transducer that can be used for sonar applications. The advantage of this technology over those currently in use is the large power density at relatively low frequencies and the ease of fabrication, allowing less expensive and more effective conformal arrays. Effective strain output and piezomagnetic coefficients have been measured, as have its dynamic properties. The results show significant improvement of the strain output and piezomagnetic coefficients, approaching the monolithic material.

Pulliam, Wade J.; McKnight, Geoffrey P.; Carman, Gregory P.

2002-07-01

299

Evaluation of principal cannabinoids in airborne particulates.  

PubMed

The determination of delta(9)-tetrahydrocannabinol (Delta9-THC), cannabidiol (CND) and cannabinol (CNB), primary active components in cannabis preparation, was carried out on airborne particulates by applying a specific procedure consisting of soot extraction by ultrasonic bath, purification by solvent partitioning, derivatization with N-(t-butyldimethylsilyl)-N-methyl-trifluoroacetamide, and separation/detection through gas chromatography coupled with tandem mass spectrometry. The optimized procedure was found suitable for measuring the three psychotropic substances at concentrations ranging from ca. 0.001 to ca. 5.0 ng cm(-3) of air, with recoveries always higher than 82%, accuracy >7.3% and precision >90%. Application of the procedure performed on field in Rome and Bari, Italy, demonstrated that all three compounds contaminate the air in Italian cities whereas in Algiers, Algeria, only cannabinol, the most stable in the atmosphere, exceeded the limit of quantification of the method. The relative percentages of the three cannabinoids in general reproduced those typical of the Cannabis sativa plant and were very different from those found in human blood, urine and sweat. PMID:19393371

Balducci, C; Nervegna, G; Cecinato, A

2009-05-01

300

Gene-particulate matter-health interactions  

SciTech Connect

Inter-individual variation in human responses to air pollutants suggests that some subpopulations are at increased risk to the detrimental effects of pollutant exposure. Extrinsic factors such as previous exposure and nutritional status may influence individual susceptibility. Intrinsic (host) factors that determine susceptibility include age, gender, and pre-existing disease (e.g., asthma), and it is becoming clear that genetic background also contributes to individual susceptibility. Environmental exposures to particulates and genetic factors associated with disease risk likely interact in a complex fashion that varies from one population and one individual to another. The relationships between genetic background and disease risk and severity are often evaluated through traditional family-based linkage studies and positional cloning techniques. However, case-control studies based on association of disease or disease subphenotypes with candidate genes have advantages over family pedigree studies for complex disease phenotypes. This is based in part on continued development of quantitative analysis and the discovery and availability of simple sequence repeats and single nucleotide polymorphisms. Linkage analyses with genetically standardized animal models also provide a useful tool to identify genetic determinants of responses to environmental pollutants. These approaches have identified significant susceptibility quantitative trait loci on mouse chromosomes 1, 6, 11, and 17. Physical mapping and comparative mapping between human and mouse genomes will yield candidate susceptibility genes that may be tested by association studies in human subjects. Human studies and mouse modeling will provide important insight to understanding genetic factors that contribute to differential susceptibility to air pollutants.

Kleeberger, Steven R. [Laboratory of Respiratory Biology, Environmental Genetics Group, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Building 101, Room D240, Research Triangle Park, NC 27705 (United States)]. E-mail: kleeber1@niehs.nih.gov; Ohtsuka, Yoshinori [Department of Pulmonary Medicine, Fukushima Medical University, Fukushima (Japan)

2005-09-01

301

Airborne particulate matter and spacecraft internal environments  

NASA Technical Reports Server (NTRS)

Instrumentation, consisting of a Shuttle Particle Sampler (SPS) and a Shuttle Particle Monitor (SPM), has been developed to characterize the airborne particulate matter in the Space Shuttle cabin during orbital flight. The SPS size selectively collects particles in four size fractions (0-2.5, 2.5-10, 10-100, and greater than 100 microns) which are analyzed postflight for mass concentration and size distribution, elemental composition, and morphology. The SPM provides a continuous record of particle concentration through photometric light scattering. Measurements were performed onboard Columbia, OV-102, during the flight of STS-32 in January 1990. No significant changes were observed in the particle mass concentration, size distribution, or chemical composition in samples collected during flight-day 2 and flight-day 7. The total mass concentration was 56 microg/cu cm with approximately half of the particles larger than 100 microns. Elemental analysis showed that roughly 70 percent of the particles larger than 2.5 microns were carbonaceous with small amounts of other elements present. The SPM showed no temporal or spatial variation in particle mass concentration during the mission.

Liu, Benjamin Y. H.; Rubow, Kenneth L.; Mcmurry, Peter H.; Kotz, Thomas J.; Russo, Dane

1991-01-01

302

Zone heated inlet ignited diesel particulate filter regeneration  

DOEpatents

An exhaust system that processes exhaust generated by an engine is provided. The system includes: a particulate filter (PF) that is disposed downstream of the engine and that filters particulates from the exhaust; and a grid that includes electrically resistive material that is segmented by non-conductive material into a plurality of zones and wherein the grid is applied to an exterior upstream surface of the PF.

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2012-06-26

303

Characterization of the Winter Midwestern Particulate Nitrate Bulge  

Microsoft Academic Search

A previously unobserved multi-state region of elevated particulate nitrate concentration was detected as a result of the expansion of the Interagency Monitoring of Protected Visual Environments (IMPROVE) network of remote-area particulate matter (PM) speciation monitoring sites into the midwestern United States that began in 2002. Mean winter ammonium nitrate concentrations exceed 4 ?g\\/m in a region centered in Iowa, which

Marc L. Pitchford; Richard L. Poirot; Bret A. Schichtel; William C. Malm; Warren White; Krystyna Trzepla-Nabaglo; Paul Wakabayashi; Charles McDade; Ann Dillner; Hege Indresand; Gavin McMeeking; Sonia Kreidenweis; Ezra Levin; Christian Carrico; Derek Day; Jeffrey Collett; Taehyoung Lee; Amy Sullivan; Suresh Raja; Patricia Brewer; Tom Moore; Mark Green; Shobha Kondragunta; Pubu Ciren; Chuanyu Xu; Delbert Eatough; Robert Farber; Marco Rodriguez; Michael Barna

2009-01-01

304

Catalytic filter bags for NOâ and particulate removal. Final report  

Microsoft Academic Search

The approach pursued by Owens-Corning Fiberglas (OCF), under the Ohio Coal Development Office sponsorship, was to control NOâ, particulates and SOâ in one unit by using a catalyst-coated fabric. Owens-Corning Fiberglas Corporation (OCF) has demonstrated the feasibility of controlling particulates and nitrogen oxide emissions with such a fabric on a bench-scale level. In this process, NOâ emissions can be reduced

Kalinowski

1992-01-01

305

Intravascular Delivery of Particulate Systems: Does Geometry Really Matter?  

Microsoft Academic Search

In cancer therapy and imaging, the systemic passive delivery of particulate systems has relied on the enhanced permeability\\u000a and retention (EPR) effect: sufficiently small particles can cross the endothelial fenestrations and accumulate in the tumor\\u000a parenchyma. The vast majority of man-made particulates exhibit a spherical shape as a result of surface energy minimization\\u000a during their synthesis. The advent of phage

Paolo Decuzzi; Renata Pasqualini; Wadih Arap; Mauro Ferrari

2009-01-01

306

Two-Stage, Dry FGD and Particulate Removal System  

Microsoft Academic Search

The two-stage, dry FGD and particulate removal system selected for use at Coyote Station in Beulah, N.D., was developed by Wheelabrator-Frye Inc. and Rockwell International Corp. (under contract with Bechtel) and consists primarily of four spray dryers and a fabric filter. Soda ash will be used as adsorbent. The conventional spray dryers produce uniformly sized particulates which are readily collectable

A. A. Reisinger; D. C. Gehri

1979-01-01

307

Pulmonary function changes in children associated with fine particulate matter  

SciTech Connect

During winter months many neighborhoods in the Seattle metropolitan area are heavily affected by particulate matter from residential wood burning. A study was conducted to investigate the relationship between fine particulate matter and pulmonary function in young children. The subjects were 326 elementary school children, including 24 asthmatics, who lived in an area with high particulate concentrations predominantly from residential wood burning. FEV1 and FVC were measured before, during and after the 1988-1989 and 1989-1990 winter heating seasons. Fine particulate matter was assessed using a light-scattering instrument. Analysis of the relationship between light scattering and lung function indicated that an increase in particulate air pollution was associated with a decline in asthmatic children's pulmonary function. FEV1 and FVC in the asthmatic children dropped an average of 34 and 37 ml respectively for each 10(-4) m-1 increase in sigma sp. This sigma sp increase corresponds to an increase in PM2.5 of 20 micrograms/m3. It is concluded that fine particulate matter from wood burning is significantly associated with acute respiratory irritation in young asthmatic children.

Koenig, J.Q.; Larson, T.V.; Hanley, Q.S.; Rebolledo, V.; Dumler, K.; Checkoway, H.; Wang, S.Z.; Lin, D.; Pierson, W.E. (Univ. of Washington, Seattle (United States))

1993-10-01

308

Fine particulate chemical composition and light extinction at Meadview, AZ  

SciTech Connect

The concentration of fine particulate nitrate, sulfate, and carbonaceous material was measured for 12-hr daynight samples using diffusion denuder samplers during the Project Measurement of Haze and Visibility Effects (MOHAVE) July to August 1992 Summer Intensive study at Meadview, AZ, just west of Grand Canyon National Park. Organic material was measured by several techniques. Only the diffusion denuder method measured the semivolatile organic material. Fine particulate sulfate and nitrate (using denuder technology) determined by various groups agreed. Based on the various collocated measurements obtained during the Project MOHAVE study, the precision of the major fine particulate species was {+-} 0.6 {mu}g/m{sup 3} organic material, {+-} 0.3 {mu}g/m{sup 3} ammonium sulfate, and {+-} 0.07 {mu}g/m{sup 3} ammonium nitrate. Fine particulate organic material was the principal particulate contributor to light extinction during the study period, with fine particulate sulfate as the second most important contributor. Particle light extinction was dominated by sulfate and organic material during periods of lowest light extinction. Combination of the extinction data and chemical mass balance analysis of sulfur oxides sources in the region indicate that the major anthropogenic contributors to light extinction were from the Los Angeles, CA, and Las Vegas, NV, urban areas. Mohave Power Project associated secondary sulfate was a negligible contributor to light extinction. 49 refs., 12 figs., 7 tabs.

Delbert J. Eatough; Wenxuan Cui; Jeffery Hull; Robert J. Farber [Brigham Young University, Provo, UT (United States). Department of Chemistry and Biochemistry

2006-12-15

309

PREFACE TO SPECIAL SECTION ON PARTICULATE MATTER: ATMOSPHERIC SCIENCES, EXPOSURE, AND THE FOURTH COLLOQUIUM ON PARTICULATE MATTER AND HUMAN HEALTH  

EPA Science Inventory

In response to epidemiological studies published over twenty years ago, at least three research communities have been intensively studying airborne particulate matter (PM). These efforts have been coordinated by approaching the source - atmospheric accumulation/receptor - exposu...

310

PROCEEDINGS: EIGHTH SYMPOSIUM ON THE TRANSFER AND UTILIZATION OF PARTICULATE CONTROL TECHNOLOGY - VOLUME 2. BAGHOUSES AND PARTICULATE CONTROL FOR NEW APPLICATIONS  

EPA Science Inventory

The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. Overall, particulate control remains a key issue in the cost and applicability of furnac...

311

PROCEEDINGS: EIGHTH SYMPOSIUM ON THE TRANSFER AND UTILIZATION OF PARTICULATE CONTROL TECHNOLOGY: VOLUME 2. BAGHOUSES AND PARTICULATE CONTROL FOR NEW APPLICATIONS  

EPA Science Inventory

The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. (overall, particulate control remains a key issue in the cost and applicability of furna...

312

Continuous particulate monitoring for emission control  

SciTech Connect

An optical continuous particle monitoring system has been developed to overcome common problems associated with emissions monitoring equipment. Opacity monitors generally use a single- or double-pass system to analyze the presence of dust particles in the flue gas stream. The particles scatter and absorb light as it passes through the stack. As the particle content in the gas stream increases due to bag failure or some other problem, the amount of light that is blocked also increases. The opacity monitor compares the amount of lost light energy to the total energy of the light available and translates the signal to percentage of opacity. Opacity monitors are typically installed to meet the requirements set forth by pollution control agencies. Most opacity monitors are designed to meet all of the requirements of the Environmental Protection Agency (EPA) 40 CFR, Part 60, Appendix B, Performance Specification. The new continuous particle monitor (CPM) increases the accuracy of emission monitoring and overcomes typical problems found in conventional emission monitoring devices. The CPM is an optically based, calibratible, continuous dust monitor that uses a microprocessor, transmitter head, and receiver head. When calibrated with an isokinetic sample, a continuous readout of particulate concentration (in mg/m[sup 3]) in the exhaust gas is provided. The system can be used as a filter bag failure system or a long-term emission trend analyzer. Formal testing was conducted to evaluate the effectiveness of the optically based CPM. The monitor was calibrated using particles of a range of compositions, size distributions, and concentrations. The feasibility of using the instrument to measure particle concentration as low as 10 mg/m[sup 3] was examined.

Bock, A.H. (BHA Group, Inc., Kansas City, MO (United States))

1993-08-01

313

Driver exposure to particulate matter in Bangkok.  

PubMed

The aims of this study were to determine the particulate matter with aerodynamic diameters > or = 2.5 microm (PM2.5) and 2.5-10 microm (PM10-2.5) exposure levels of drivers and to analyze the proportion of elemental carbon (EC) and organic carbon (OC) in PM2.5 in Bangkok, Thailand. Four bus routes were selected. Measurements were conducted over 10 days in August (rainy season) 2008 and 8 days in January (dry season) 2009. The mean PM2.5 exposure level of the Tuk-tuk drivers was 86 microg/m3 in August and 198 microg/m3 in January. The mean for the non-air-conditioned bus drivers was 63 microg/m3 in August and 125 microg/m3 in January. The PM2.5 and PM10-2.5 exposure levels of the drivers in January were approximately twice as high as those in August. The proportion of total carbon (TC) in PM2.5 to the PM2.5 level in August (0.97 +/- 0.28 microg/m3) was higher than in January (0.65 +/- 0.13 microg/m3). The proportion of OC in the TC of the PM2.5 in August (0.51 +/- 0.08 microg/m3) was similar to that in January (0.65 +/- 0.07 microg/m3). The TC exposure by PM25 in January (81 +/- 30 microg/m3) remained higher than in August (56-21 microg/m3). The mean level of OC in the PM2.5 was 29 +/- 13 microg/m3 in August and 50 +/- 24 microg/m3 in January. In conclusion, the PM exposure level in Bangkok drivers was higher than that in the general environment, which was already high, and it varied with the seasons and vehicle type. This study also demonstrated that the major component of the PM was carbon, likely derived from vehicles. PMID:22393811

Jinsart, W; Kaewmanee, C; Inoue, M; Hara, K; Hasegawa, S; Karita, K; Tamura, K; Yano, E

2012-01-01

314

Semivolatile Particulate Organic Material Southern Africa during SAFARI 2000  

NASA Technical Reports Server (NTRS)

During August and September 2000, the University of Washington's Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the h e troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna frre emissions averaged 130 micrograms per cubic meter. This aerosol was 85% carbonaceous mated.

Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.

2005-01-01

315

Major components of China's anthropogenic primary particulate emissions.  

SciTech Connect

This paper presents the first comprehensive estimates of particulate emissions in China by size distribution and major components. Using a technology-based emission inventory approach, we are able to classify particulate emissions into three size ranges, TSP, PM{sub 10} and PM{sub 2.5}, and identify the contributions of black carbon (BC), organic carbon (OC), Ca and Mg. Total particulate emissions are estimated to be 27.4 Tg for the year 2001, of which 17.8 Tg are PM{sub 10} and 12.7 Tg are PM{sub 2.5}. Industrial processes are the major sources of particles over all three size ranges, but residential biofuel use and transportation sources become increasingly important for PM{sub 10} and PM{sub 2.5}. The industrialized coastal provinces, such as Shandong, Jiangsu and Hebei, are the major sources of particulate emissions. The industrialized and developing regions show different characteristic emission ratios of PM{sub 2.5}/TSP, (BC+OC)/PM{sub 2.5} and (Ca+Mg)/TSP. In the future, we can expect significant reductions in primary particulate emissions and major changes in the patterns of size and species.

Zhang, Q.; Streets, D. G.; He, K.; Klimont, Z.; Decision and Information Sciences; Tsinghua Univ.; International Inst. for Applied Systems Analysis

2007-10-01

316

Particulate size distribution cascade analyzer for spacecraft contamination monitoring  

NASA Technical Reports Server (NTRS)

A cascade particulate analyzer was developed for nearly real time measurement of the contaminating particulate size distribution in the spacecraft interior ambient environment and as a real time total impacting particulate mass monitor under vacuum conditions. The analyzer has four stages, the first stage is a basic 10 MHz quartz crystal microbalance used widely on spacecraft (such as Skylab) for contamination monitoring purposes. In this application the front sensing crystal is coated with a low vapor pressure adhesive grease which captures impacting particles. This first stage has a wide viewing angle and measures total particulate mass impacting the crystal while the unit is exposed to the vacuum environment. The remaining three states form an aerodynamic impaction cascade with individual quartz crystal microbalances at each stage acting as accumulated mass sensing elements. These three stages thus give relative mass distribution of particulates in three ranges, particles having effective diameter greater than 5 micron, particles between 1 and 5 micron diameter and particles 0.3 to 1 micron diameter.

Wallace, D. A.; Chuan, R. L.

1975-01-01

317

Small volume particulate and non-particulate sample collection for fluidic systems  

NASA Astrophysics Data System (ADS)

In fluidic systems, it is often desirable to collect samples in the hydrated state at one location. Most methods devised to do this are often complex. In this work, we present a method that uses a simple squeeze flow. We demonstrate its use in the collection of cells (algal cells), particulates (microbeads and fluorescent nanobeads) and non-particulates (EGFP). This fluidic system is amenable for high content microscopy. An assumption often made is that objects being observed are fixed spatially and are sufficiently populated. Without the ability to collect, this can lead to the need for searching through multiple field of views (FOVs). We report that the generation of a squeeze flow by the circular coverslip onto a liquid sample allows for objects to be acquired at the rim regions of the circular coverslip. By using a coverslip of 13 mm diameter and sample volumes between 2 ?L and 4 ?L, the coverslip was completely filled without any excess flow beyond its outer rim. Furthermore, sample compression speeds between 100 ?m/s and 1000 ?m/s did not change the effect of the object collection outcome. A comparison was made between manually placing the coverslip on the liquid sample by hand and using a motorised translator to generate the squeeze flow and in both cases, similar outcomes were obtained. Quantitative measurements and image analysis confirmed that all the objects investigated had been displaced and relocated at the rim regions of the coverslip at a very high degree and ready to be collected. Also by using a metal cylinder and probe tip, pre-concentration of material was achieved.

Cheong, Brandon H.

2013-12-01

318

Method for dispersing catalyst onto particulate material and product thereof  

DOEpatents

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal.

Utz, Bruce R. (Pittsburgh, PA); Cugini, Anthony V. (Pittsburgh, PA)

1992-01-01

319

Method for dispersing catalyst onto particulate material and product thereof  

SciTech Connect

A method for dispersing finely divided catalyst precursors onto the surface of coal or other particulate material includes the steps of forming a wet paste mixture of the particulate material and a liquid solution containing a dissolved transition metal salt, for instance a solution of ferric nitrate. The wet paste mixture is in a state of incipient wetness with all of this solution adsorbed onto the surfaces of the particulate material without the presence of free moisture. On adding a precipitating agent such as ammonia, a catalyst precursor such as hydrated iron oxide is deposited on the surfaces of the coal. The catalyst is activated by converting it to the sulfide form for the hydrogenation or direct liquefaction of the coal. 2 figs.

Utz, B.R.; Cugini, A.V.

1992-12-01

320

Cometary particulate analyzer. [mass spectrometry of laser plasmas  

NASA Technical Reports Server (NTRS)

A concept for determining the relative abundance of elements contained in cometary particulates was evaluated. The technique utilizes a short, high intensity burst of laser radiation to vaporize and ionize collected particulate material. Ions extracted from this laser produced plasma are analyzed in a time of flight mass spectrometer to yield an atomic mass spectrum representative of the relative abundance of elements in the particulates. Critical aspects of the development of this system are determining the ionization efficiencies for various atomic species and achieving adequate mass resolution. A technique called energy-time focus, which utilizes static electric fields to alter the length of the ion flight path in proportion to the ion initial energy, was used which results in a corresponding compression to the range of ion flight times which effectively improves the inherent resolution. Sufficient data were acquired to develop preliminary specifications for a flight experiment.

Friichtenicht, J. F.; Miller, D. J.; Utterback, N. G.

1979-01-01

321

IMPACT OF ENGINE OIL CONSUMPTION ON PARTICULATE EMISSIONS  

Microsoft Academic Search

By October 2005, Euro 4 emission limits will be introduced in Europe for on-road trucks, reducing the particulate emissions from 0.10 g\\/kW-hr to 0.02\\/0.03 g\\/kW-hr, as measured over the European ESC\\/ETC cycles. By 2007, the US EPA 2007 emission limits will be introduced in the States for on-road trucks, reducing the particulate emissions from 0.10 g\\/bhp-hr to 0.01 g\\/bhp-hr, as

Kent Froelund; Ertan Yilmaz

322

Particulate Emissions Hazards Associated with Fueling Heat Engines  

NASA Technical Reports Server (NTRS)

All hydrocarbon- (HC-) fueled heat engine exhaust (tailpipe) emissions (<10 to 140 nm) contribute as health hazards, including emissions from transportation vehicles (e.g., aircraft) and other HC-fueled power systems. CO2 emissions are tracked, and when mapped, show outlines of major transportation routes and cities. Particulate pollution affects living tissue and is found to be detrimental to cardiovascular and respiratory systems where ultrafine particulates directly translocate to promote vascular system diseases potentially detectable as organic vapors. This paper discusses aviation emissions, fueling, and certification issues, including heat engine emissions hazards, detection at low levels and tracking of emissions, and alternate energy sources for general aviation.

Hendricks, Robert C.; Bushnell, Dennis M.

2010-01-01

323

Optical Properties of Silver Particulate Films on Modified Polymer Substrates  

NASA Astrophysics Data System (ADS)

Results of the investigations carried out on the optical properties of particulate films deposited on 8 MeV electron beam irradiated polystyrene (PS) and on blends of PS and Poly (4-vinyl pyridine) (P4VP) are reported. It is observed that absorption maxima shift towards higher wavelength for films deposited on irradiated polystyrene and on blends of PS and P4VP. These results indicate that morphology of the particulate films can be changed by tuning the metal polymer interaction in an inert polymer through electron beam irradiation or by blending it with an interacting polymer like P4VP.

Gurumurthy, S. C.; Pattabi, Manjunatha; Sanjeeva, Ganesh

2011-07-01

324

Apparatus and method for void/particulate detection  

DOEpatents

Apparatus and method are described for detecting voids and particulates in a fluid within a containing vessel. A diffuse ultrasonic signal is coupled into the fluid by a first transducer and the portion of the ultrasonic signal transmitted through the fluid is detected by a second transducer. The received signal is analyzed by a processor to determine the void fraction of the fluid responsive to the attenuation of the received ultrasonic signal. In addition, voids and particulates are detected by evaluating the increase in side-band energy of the received signal.

Claytor, T.N.; Ockert, C.E.; Randall, R.

1986-06-24

325

Is atmospheric particulate matter inhibiting marine primary productivity  

SciTech Connect

Present deposition rates of atmospheric particulate matter do not appear great enough to inhibit marine primary productivity except, perhaps, at the sea-surface microlayer. Milligram/liter quantities of air particulate matter added to seawater result in an exponential reduction in photosynthetic /sup 14/C assimilation of natural marine phytoplankton populations. Urban particles are 6 times more toxic than rural particles. The ratios of soluble trace elements from equal amounts of urban (Seattle) to rural (Quillayute) atmospheric particles are as follows: As, 112; Br, 6.4; Cr, 3.4; Cu, 3.7; Ni, 3.0; Pb, 36; V, 2.7; and Zn, 2.2.

Hardy, J.T.; Crecelius, E.A.

1981-09-01

326

Apparatus and method for void/particulate detection  

DOEpatents

Apparatus and method for detecting voids and particulates in a fluid within a containing vessel. A diffuse ultrasonic signal is coupled into the fluid by a first transducer and the portion of the ultrasonic signal transmitted through the fluid is detected by a second transducer. The received signal is analyzed by a processor to determine the void fraction of the fluid responsive to the attenuation of the received ultrasonic signal. In addition, voids and particulates are detected by evaluating the increase in side-band energy of the received signal.

Claytor, Thomas N. (Woodridge, IL); Ockert, Carl E. (Vienna, VA); Randall, Richard (Canoga Park, CA)

1987-01-01

327

Research priorities for airborne particulates matter in the United States  

SciTech Connect

Despite substantial progress in reducing air pollution over the past 30 years, particulates remain a poorly understood health concern that requires further study. The article provides a brief overview of the work of an independent National Research Council (NRC) Committee on particulate matter (PM). It highlights the committee's process for developing during its deliberations. It reflects on the committee as a potential model to provide guidance on a broad research area in which findings may have significant policy implications. 13 refs., 1 fig., 1 tab.

Samet, J.; Wassle, R.; Holmes, K.J.; Abt, E.; Bakshi, K. [John Hopkins University (US). Bloomberg School of Public Health

2005-07-15

328

40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...  

Code of Federal Regulations, 2010 CFR

...total suspended particulate matter in the ambient air is computed...high elevations. The actual particulate matter concentration can be calculated...undefined because of the complex nature of atmospheric particulate matter and the difficulty in...

2010-07-01

329

40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...  

Code of Federal Regulations, 2010 CFR

...total suspended particulate matter in the ambient air is computed...high elevations. The actual particulate matter concentration can be calculated...undefined because of the complex nature of atmospheric particulate matter and the difficulty in...

2009-07-01

330

Advanced hybrid particulate collector. Quarterly technical progress report, July 1--September 30, 1996.  

National Technical Information Service (NTIS)

The objective for this quarter was to test the advanced hybrid particulate collector (AHPC) in real flue gas conditions. The initial tests were performed on the particulate test combustor (PTC) firing Absoloka subbituminous using two types of bags: PTFE a...

S. J. Miller G. L. Schelkoph

1996-01-01

331

40 CFR 60.48b - Emission monitoring for particulate matter and nitrogen oxides.  

Code of Federal Regulations, 2010 CFR

...particulate matter and nitrogen oxides. 60.48b...particulate matter and nitrogen oxides...combusting coal, wood or municipal-type solid waste, the span value for...residual oil having a nitrogen content of 0.30...

2010-07-01

332

40 CFR 60.48b - Emission monitoring for particulate matter and nitrogen oxides.  

Code of Federal Regulations, 2010 CFR

...particulate matter and nitrogen oxides.] 40 ...particulate matter and nitrogen oxides...combusting coal, wood or municipal-type solid waste, the span value for...residual oil having a nitrogen content of 0.30...

2009-07-01

333

ANALYSIS OF LEAD IN CANDLE PARTICULATE EMISSIONS BY XRF USING UNIQUANT 4  

EPA Science Inventory

As part of an extensive program to study the small combustion sources of indoor fine particulate matter (PM), candles with lead-core wicks were burned in a 46-L glass flow- through chamber. The particulate emissions with aerodynamic diameters ...

334

77 FR 33002 - Proposed Extension of Existing Information Collection; Health Standards for Diesel Particulate...  

Federal Register 2010, 2011, 2012, 2013

...Information Collection; Health Standards for Diesel Particulate Matter Exposure (Underground...prevention of injuries in coal or other mines. Diesel particulate matter (DPM) is a probable...consists of tiny particles present in diesel engine exhaust that can readily...

2012-06-04

335

Worker exposure to chemical agents in the manufacture of rubber tires and tubes: particulates.  

PubMed

The Occupational Health Studies Group industrial hygiene studies at a group of 14 tire and tube manufacturing plants chosen to represent a cross-section of the industry include numerous evaluations of potential exposure to airborne particulate matter. Results of these environmental particulate sampling studies are reported by plant and by occupational groups within plants. High volume, open face and cyclone samplers were employed to evaluate both personnel and area particulate concentrations. The concentrations of particulates yielded by high volume and open face total particulate samplers are compared with those of comparison samples of respirable material. Personnel samples of particulates are compared with general air samples taken in the same work areas. An overall review and comparison is given of particulate exposures to workers in various occupational title groups where particulate materials are released to the air from processes or operations. PMID:7395731

Williams, T M; Harris, R L; Arp, E W; Symons, M J; Van Ert, M D

1980-03-01

336

77 FR 34830 - Revisions to Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate...  

Federal Register 2010, 2011, 2012, 2013

...and Budget PM 2.5 Fine Particulate Matter, Less Than 2.5 Micrometers PM Particulate Matter RIA Regulatory Impact Analysis SO 2 ...budget depends. Because of the conservative nature of design values (representing broadly...

2012-06-12

337

78 FR 73698 - Prevention of Significant Deterioration for Particulate Matter Less Than 2.5 Micrometers...  

Federal Register 2010, 2011, 2012, 2013

...Significant Deterioration for Particulate Matter Less Than 2.5 Micrometers...Significant Impact Levels (SILs) for particulate matter less than 2.5 micrometers...because it is ministerial in nature. The EPA will initiate a...

2013-12-09

338

Impact of Biodiesel on the Oxidation Kinetics and Morphology of Diesel Particulate.  

National Technical Information Service (NTIS)

We compare the oxidation characteristics of four different diesel particulates generated with a modern light-duty engine. The four particulates represent engine fueling with conventional ultra-low sulfur diesel (ULSD), biodiesel, and two intermediate blen...

A. Strzelec T. J. Toops T. S. Daw

2011-01-01

339

77 FR 12769 - Approval and Promulgation of Implementation Plans; Georgia; Macon; Fine Particulate Matter 2002...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Georgia; Macon; Fine Particulate Matter 2002 Base Year Emissions Inventory AGENCY: Environmental Protection...proposing to approve the fine particulate matter (PM 2.5 ) 2002 base year emissions inventory, portion of the State...

2012-03-02

340

77 FR 12526 - Approval and Promulgation of Implementation Plans; Georgia; Atlanta; Fine Particulate Matter 2002...  

Federal Register 2010, 2011, 2012, 2013

...Implementation Plans; Georgia; Atlanta; Fine Particulate Matter 2002 Base Year Emissions Inventory AGENCY: Environmental Protection...proposing to approve the fine particulate matter (PM 2.5 ) 2002 base year emissions inventory, portion of the State...

2012-03-01

341

PROCEEDINGS: EIGHTH SYMPOSIUM ON THE TRANSFER AND UTILIZATION OF PARTICULATE CONTROL TECHNOLOGY - VOLUME 1. ELECTROSTATIC PRECIPITATORS  

EPA Science Inventory

The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. Overall, particulate control remains a key issue in the cost and applicability of furnac...

342

PROCEEDINGS: EIGHTH SYMPOSIUM ON THE TRANSFER AND UTILIZATION OF PARTICULATE CONTROL TECHNOLOGY: VOLUME 1. ELECTROSTATIC PRECIPITATORS  

EPA Science Inventory

The two-volume proceedings describe the latest research and development efforts to improve particulate control devices, while treating traditional concerns of operational cost and compliance. (overall, particulate control remains a key issue in the cost and applicability of furna...

343

CONTRIBUTION OF SEMI-VOLATILE PARTICULATE MATTER TO AMBIENT SUSPENDED FINE PARTICLE MASS  

EPA Science Inventory

Scope: The periodic (5 years) review of the National Ambient Air Quality Standard (NAAQS) for particulate matter (PM) and the subsequent determination by EPA and NAS of particulate matter research needs have identified areas of uncertainty including exposure measurement th...

344

40 CFR 49.128 - Rule for limiting particulate matter emissions from wood products industry sources.  

Code of Federal Regulations, 2013 CFR

...limiting particulate matter emissions from wood products industry sources. 49.128...limiting particulate matter emissions from wood products industry sources. (a) What...matter that may be emitted from certain wood products industry sources operating...

2013-07-01

345

COPPER-DEPENDENT INFLAMMATION AND NUCLEAR FACTOR-KB ACTIVATION BY PARTICULATE AIR POLLUTION  

EPA Science Inventory

Particulate air pollution causes increased cardiopulmonary morbidity and mortality, but the chemical determinants responsible for its biologic effects are not understood. We studied the effect of total suspended particulates collected in Provo, Utah, an area where an increase in ...

346

42 CFR 84.206 - Particulate tests; respirators with filters; minimum requirements; general.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Particulate tests; respirators with filters; minimum requirements...Respirators § 84.206 Particulate tests; respirators with filters; minimum requirements...84.207. (b) In addition to the test requirements set forth in paragraph...

2012-10-01

347

40 CFR 60.45c - Compliance and performance test methods and procedures for particulate matter.  

Code of Federal Regulations, 2010 CFR

...and procedures for particulate matter. 60.45c Section...FOR NEW STATIONARY SOURCES Standards of Performance...and procedures for particulate matter. (a) The...whichever is later, for condensable PM emissions,...

2010-07-01

348

INSTRUMENTATION FOR MONITORING THE OPACITY OF PARTICULATE EMISSIONS CONTAINING CONDENSED WATER  

EPA Science Inventory

On-stack instrumentation and methodology were developed to monitor the opacity of particulate pollutants in stationary source emissions containing condensed water. The instrument continuously extracts and measures the opacity of representative samples of particulate effluent. It ...

349

STATISTICAL ISSUES IN THE STUDY OF AIR POLLUTION INVOLVING AIRBORNE PARTICULATE MATTER  

EPA Science Inventory

Epidemiological research in the early 1990s focusing on health effects of airborne particulate matter pointed to a statistical association between increases in concentration of particulate in ambient air and increases in daily nonaccidental mortality, particularly among the eld...

350

Analysis of Weekday/Weekend Differences in Ambient Particulate Nitrate Concentrations and Formation in Southern California.  

National Technical Information Service (NTIS)

One of the principal contributors to fine particulate matter (PM) concentrations in California's South Coast Air Basin (SoCAB), especially during the months of October through January, is particulate nitrate. To improve understanding of the effects of vol...

C. L. Blanchard S. Tanenbaum

2002-01-01

351

40 CFR 86.1320-90 - Gas meter or flow instrumentation calibration; particulate, methanol, and formaldehyde measurement.  

Code of Federal Regulations, 2010 CFR

...particulate, methanol, and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters...filters, methanol impingers and formaldehyde impingers. These...

2010-07-01

352

40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.  

Code of Federal Regulations, 2010 CFR

...particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas meters...filters, methanol impingers and formaldehyde impingers. These...

2009-07-01

353

Personal Coarse Particulate Matter Exposures in an Adult Cohort  

EPA Science Inventory

Volunteers associated with the North Carolina Adult Asthma and Environment Study (NCAAES) participated in an investigation of personal daily exposures to coarse and fine particulate matter size fractions (PM10-2.5, PM2.5). Data from these personal measuremen...

354

AIR QUALITY CRITERIA FOR PARTICULATE MATTER (Final Report, Oct 2004)  

EPA Science Inventory

EPA has completed the process of updating and revising, where appropriate, its Air Quality Criteria for Particulate Matter (PM) as issued in 1996 (usually referred to as the Criteria Document). Sections 108 and 109 of the Clean Air Act require that EPA carry out a periodic revi...

355

PREDICTION OF FINE PARTICULATE LEVELS AT UNMONITORED LOCATIONS  

EPA Science Inventory

In November and December of 1999, air concentrations of ultrafine, fine, and coarse particulate matter were measured at two intensive sites in El Paso, Texas. The intensive sites included collocated measurements of NO2 and volatile organic compounds (VOCs) in the air from both...

356

Spectroelectrochemical study of TiO 2 particulate films  

Microsoft Academic Search

Transparent TiO2 film is prepared by sintering colloids on a conducting glass support. TiO2 particulate film exhibits reversible photochromic and electrochromic behaviors. Thin semiconductor films provide a convenient way to enhance the efficiency of the photocatalytic degradation. The electrochemically assisted photocatalysis can be applied to photocatalytic reactors with immobilized semiconductor particles.

Lianyong Su; Zuhong Lu

1997-01-01

357

Costs of Particulate Matter Controls for Nonfossil Fuel Fired Boilers.  

National Technical Information Service (NTIS)

This report is a resource document for the development of Federal standards of performance for control of particulate matter from new nonfossil fuel-fired boilers ranging in size from 30 to 400 million Btu/hour heat input. Capital and annualized costs for...

K. W. Barnett W. D. Kwapil S. C. Margerum

1983-01-01

358

EVALUATION OF FOUR NOVEL FINE PARTICULATE COLLECTION DEVICES  

EPA Science Inventory

The report gives results of an experimental performance evaluation of four novel fine particulate control devices: the Johns-Manville Cleanable High-Efficiency Air Filtration (CHEAF) System, the APS Electrostatic Scrubber, the APS Electrotube, and the TRW Charged Droplet Scrubber...

359

Determination of PAHs in particulate air by micellar liquid chromatography  

SciTech Connect

An acetonitrile/0.20M SDS mobile phase was used to determine PAHs by HPLC with fluorimetric detection. Because the peak area is greater the method is more sensitive than using an acetonitrile/water mobile phase. The method was applied to determine PAHs in particulate air samples and the results are in good agreement with those found by GC.

Kayali, M.N.; Rubio-Barroso, S.; Polo-Diez, L.M. (Complutense Univ. of Madrid (Spain). Dept. of Analytical Chemistry)

1994-01-01

360

Toward Distinguishing Woodsmoke and Diesel Exhaust in Ambient Particulate Matter  

Microsoft Academic Search

Particulate matter (PM) from biomass burning and diesel exhaust has distinct X-ray spectroscopic, carbon specific signatures, which can be employed for source apportionment. Characterization of the functional groups of a wide selection of PM samples (woodsmoke, diesel soot, urban air PM) was carried out using the soft X-ray spectroscopy capabilities at the synchrotron radiation sources in Berkeley (ALS) and Brookhaven

A. Braun; F. E. Huggins; A. Kubatova; S. Wirick; M. M. Maricq; B. S. Mun; J. D. McDonald; K. E. Kelly; N. Shah; G. P. Huffman

2008-01-01

361

Mechanisms governing fine particulate emissions from coal flames  

SciTech Connect

The overall objectives of this project are to provide a basic understanding of the principal processes that govern fine particulate formation in pulverized coal flames, and develop procedures to predict the levels of emission of fine particles from pulverized coal combustors. (VC)

Clark, W.D.; Chen, S.L.; Kramlich, J.C.; Newton, G.H.; Seeker, W.R. (Energy and Environmental Research Corp., Irvine, CA (United States)); Samuelsen, G.S. (California Univ., Irvine, CA (United States))

1988-11-01

362

Partitioning of copper onto suspended particulate matter in river waters  

Microsoft Academic Search

Suspended particles and river water from the Susquehanna River, White Clay Creek and the Delaware River were collected to experimentally study the partitioning of copper. The effects of many factors that may influence the partitioning coefficient (Kd) including pH, total suspended solids (TSS), total copper concentration ([Cu]T), dissolved organic matter (DOM), particulate organic matter (POM), hardness, and ionic strength were

Yuefeng Lu; Herbert E Allen

2001-01-01

363

40 CFR 60.402 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

... Standards of Performance for Phosphate Rock Plants § 60.402 Standard for particulate...atmosphere: (1) From any phosphate rock dryer any gases which: (i) Contain...030 kilogram per megagram of phosphate rock feed (0.06 lb/ton), or...

2013-07-01

364

Coupled Particulate and Continuum Model for Nanoparticle Targeted Delivery  

PubMed Central

Prediction of nanoparticle (NP) distribution in a vasculature involves transport phenomena at various scales and is crucial for the evaluation of NP delivery efficiency. A combined particulate and continuum model is developed to model NP transport and delivery processes. In the particulate model ligand-receptor binding kinetics is coupled with Brownian dynamics to study NP binding on a microscale. An analytical formula is derived to link molecular level binding parameters to particulate level adhesion and detachment rates. The obtained NP adhesion rates are then coupled with a convection-diffusion-reaction model to study NP transport and delivery at macroscale. The binding results of the continuum model agree well with those from the particulate model. The effects of shear rate, particle size and vascular geometry on NP adhesion are investigated. Attachment rates predicted by the analytical formula also agree reasonably well with the experimental data reported in literature. The developed coupled model that links ligand-receptor binding dynamics to NP adhesion rate along with macroscale transport and delivery processes may serve as a faster evaluation and prediction tool to determine NP distribution in complex vascular networks.

Tan, Jifu; Wang, Shunqiang; Yang, Jie; Liu, Yaling

2013-01-01

365

Thermal conductivity measurements of particulate materials 2. results  

Microsoft Academic Search

A line-heat source apparatus was assembled for the purpose of measuring thermal conductivities of particulate samples under low pressures of a carbon dioxide atmosphere. The primary result of this project is the compilation of the first comprehensive suite of measurements of the dependence of thermal conductivity on particle size. The thermal conductivity increases with increasing particle size and atmospheric pressure.

Marsha A. Presley; Philip R. Christensen

1997-01-01

366

Particulate bioprocessing: A novel process strategy for biorefineries  

Microsoft Academic Search

A novel process strategy based on particulate bioprocessing has been developed for the production of value-added chemicals and biofuels. The process, which involves two main steps, fungal fermentation and discontinuous extraction, leads to the production of generic fermentation feedstocks from cereals. Partially pearled whole wheat grains were used as substrate for the growth of Aspergillus awamori in a packed bed

Carolina Botella; Ana B. Diaz; Ruohang Wang; Apostolis Koutinas; Colin Webb

2009-01-01

367

Evaluation of a Direct Personal Coarse Particulate Matter Monitor  

EPA Science Inventory

One aspect of the North Carolina Adult Asthma and Environment study (NCAAES) was to evaluate personal exposures to coarse particulate matter (PM 10-2.5) and their associated variability. As part of this, we examined the ability of a community-based monitor to act as...

368

LOCAL AND REGIONAL CONTRIBUTIONS TO URBAN PARTICULATE MATTER  

EPA Science Inventory

The report summarizes the data analysis of two extensive field studies on urban particulate matter, the 1974-77 St. Louis (RAPS) and the July/August 1982 Philadelphia (PAFS) studies. The major conclusion of the study is that in both cities the majority (more than 50%) of the tota...

369

EVALUATION OF PARTICULATE MASS MONITORS USING THE BETA GAUGE TECHNIQUE  

EPA Science Inventory

A field study was conducted to evaluate two commercially available beta gauge instruments for measuring particulate mass concentrations in stationary source emissions. Performance of the instruments was compared with a manual method of measurement at a ferrite rotary-kiln calcine...

370

Inductively heated particulate matter filter regeneration control system  

DOEpatents

A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.

Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J

2012-10-23

371

A POPULATION EXPOSURE MODEL FOR PARTICULATE MATTER: SHEDS-PM  

EPA Science Inventory

The US EPA National Exposure Research Laboratory (NERL) has developed a population exposure and dose model for particulate matter (PM) that will be publicly available in Fall 2002. The Stochastic Human Exposure and Dose Simulation (SHEDS-PM) model uses a probabilistic approach ...

372

Turkish Primary Students' Conceptions about the Particulate Nature of Matter  

ERIC Educational Resources Information Center

This study was conducted to determine 4th, 5th, and 6th grade primary students' conceptions about the particulate nature of matter in daily-life events. Five questions were asked of students and interviews were used to collect data. The interviews were conducted with 12 students, four students from each grade, after they finished the formal…

Ozmen, Haluk

2011-01-01

373

Students' Understanding of the Particulate Nature of Matter  

ERIC Educational Resources Information Center

The particulate nature of matter is identified in science education standards as one of the fundamental concepts that students should understand at the middle school level. However, science education research in indicates that secondary school students have difficulties understanding the structure of matter. The purpose of the study is to describe…

Singer, Jonathan E.; Tal, Revital; Wu, Hsin-Kai

2003-01-01

374

Bayesian Hierarchical Modeling of Cardiac Response to Particulate Matter Exposure  

EPA Science Inventory

Studies have linked increased levels of particulate air pollution to decreased autonomic control, as measured by heart rate variability (HRV), particularly in populations such as the elderly. In this study, we use data obtained from the 1998 USEPA epidemiology-exposure longitudin...

375

SIMPLEX OPTIMIZATION OF MULTIELEMENT ULTRASONIC EXTRACTION OF ATMOSPHERIC PARTICULATES  

EPA Science Inventory

A Simplex search was used to locate an optimum for an ultrasonic extraction of trace elements from atmospheric particulates collected on glass fiber high-volume sampler filters. The optimized procedure produced quantitative results for 13 elements with precisions of 10% or less, ...

376

Ceramic filters for removal of particulates from hot gas streams  

Microsoft Academic Search

The primary goal is to demonstrate the performance of a new ceramic filter in removing particulate matter from hot gas streams produced in advanced coal conversion processes. The specific objectives are threefold: (1) Development of full size ceramic filters suitable for hot gas filtration; (2) Demonstration of ceramic filters in long term (ca. 1000 hrs) field trials; and (3) Development

1992-01-01

377

Integrated Science Assessment for Particulate Matter (Second External Review Draft)  

EPA Science Inventory

EPA has announced that the Second External Review Draft of the Integrated Science Assessment (ISA) for Particulate Matter (PM) have been made available for independent peer review and public review. The ISA reflects the latest scientific knowledge useful in indicating the kind...

378

Integrated Science Assessment for Particulate Matter (First External Review Draft)  

EPA Science Inventory

EPA has announced that the First External Review Draft of the Integrated Science Assessment (ISA) for Particulate Matter and related Annexes have been made available for independent peer review and public review. This draft ISA document represents a concise synthesis and e...

379

TECHNIQUE FOR IN SITU CALIBRATION OF PARTICULATE MASS MONITORS  

EPA Science Inventory

Two types of aerosol generators, the Riker Laboratories metered spray can and the Mistogen EN145 ultrasonic nebulizer, were evaluated by laboratory measurements for application to the in situ calibration of particulate mass monitors for stationary sources. The metered spray can d...

380

Characterizing particulate drug-delivery carriers with atomic force microscopy  

Microsoft Academic Search

This work discusses the benefits of employing an atomic force microscope (AFM) in the characterization of the particulate-type drug-delivery carriers. AFM can provide invaluable information about the physicochemical characteristics of the carriers that play an important role in determining the performance of the drug delivery systems (DDS). A lot of this information cannot be obtained from other characterization techniques due

Ashish Garg; Efrosini Kokkoli

2005-01-01

381

Particulate matter neurotoxicity in culture is size-dependent  

Microsoft Academic Search

Exposure to particulate matter (PM) air pollution produces inflammatory damage to the cardiopulmonary system. This toxicity appears to be inversely related to the size of the PM particles, with the ultrafine particle being more inflammatory than larger sizes. Exposure to PM has more recently been associated with neurotoxicity. This study examines if the size-dependent toxicity reported in cardiopulmonary systems also

Patricia Gillespie; Julianne Tajuba; Morton Lippmann; Lung-Chi Chen; Bellina Veronesi

382

Turkish Pupils' Conceptions of the Particulate Nature of Matter  

ERIC Educational Resources Information Center

The purpose of this research study is to explore year 6, 8 & 11 (13, 15 and 17 years old respectively) Turkish pupils' views about the particulate nature of matter within the context of phase changes. About 300 pupils participated in the study. Questionnaires distributed to year 6, 8 and 11 pupils included 6-item open-ended questions about (a)…

Boz, Yezdan

2006-01-01

383

BALLOON-BORNE PARTICULATE SAMPLING FOR MONITORING POWER PLANT EMISSIONS  

EPA Science Inventory

The report describes a lightweight remote-controlled sampler, carried aloft by a tethered balloon, that has been developed to collect particulates from the plumes of fossil-fueled power plants at various downwind distances. The airborne sampler is controlled from the ground by a ...

384

Stability of Metal Particle and Metal Particulate Media.  

National Technical Information Service (NTIS)

Metal particulate (MP) video tape was launched for 8 mm video tape in 1985. Since then MP tapes have been applied to several consumer formats and instrumental formats because of its superior electrical performance. Recently data storage media, such as DDS...

K. Okamoto

1992-01-01

385

HIGH-TEMPERATURE AND HIGH-PRESSURE PARTICULATE CONTROL REQUIREMENTS  

EPA Science Inventory

The report reviews and evaluates high-temperature and high-pressure particulate cleanup requirements of existing and proposed energy processes. The study's aims are to define specific high-temperature and high-pressure particle removal problems, to indicate potential solutions, a...

386

DIII-D Dust Particulate Characterization (June 1998 Vent)  

SciTech Connect

Dust is a key component of fusion power device accident source term. Understanding the amount of dust expected in fusion power devices and its physical and chemical characteristics is needed to verify assumptions currently used in safety analyses. An important part of this safety research and development work is to characterize dust from existing experimental tokamaks. In this report, we present the collection, data analysis methods used, and the characterization of dust particulate collected from various locations inside the General Atomics DIII-D vacuum vessel following the June 1998 vent. The collected particulate was analyzed at the Idaho National Engineering and Environmental Laboratory (INEEL). Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Choice of collection technique is important because the sampling method used can bias the particle size distribution collected. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Seventeen samples were collected including plasma facing surfaces in lower, upper, and horizontal locations, surfaces behind floor tiles, surfaces behind divertor tiles, and surfaces behind ceiling tiles. The results of the analysis are presented.

Carmack, William Jonathan

1999-01-01

387

DIII-D dust particulate characterization (June 1998 Vent)  

SciTech Connect

Dust is a key component of fusion power device accident source term. Understanding the amount of dust expected in fusion power devices and its physical and chemical characteristics is needed to verify assumptions currently used in safety analyses. An important part of this safety research and development work is to characterize dust from existing experimental tokamaks. In this report, the authors present the collection, data analysis methods used, and the characterization of dust particulate collected from various locations inside the General Atomics DIII-D vacuum vessel following the June 1998 vent. The collected particulate was analyzed at the Idaho National Engineering and Environmental Laboratory (INEEL). Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Choice of collection technique is important because the sampling method used can bias the particle size distribution collected. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Seventeen samples were collected including plasma facing surfaces in lower, upper, and horizontal locations, surfaces behind floor tiles, surfaces behind divert or tiles, and surfaces behind ceiling tiles. The results of the analysis are presented.

Carmack, W.J.

1999-01-01

388

The Role of Particulate Matter in Exacerbation of Atopic Asthma  

Microsoft Academic Search

Increasing evidence shows that elevated levels of particulate matter (PM) can exacerbate existing asthma, while evidence that PM can promote the induction of asthma is limited. PM in ambient air has been associated with increased emergency room visits and medication use by asthmatics. Controlled human exposure studies of acid aerosols suggest increased responses among adolescent asthmatics. Increased ambient and indoor

Stephen H. Gavett; Hillel S. Koren

2001-01-01

389

Speciation of riverine particulate phosphorus during rain events  

Microsoft Academic Search

Suspended sediments collected during rain events were analysed to assess the maximum potential bioavailability of particulate phosphorus (PP). Physical (separation by particle size) and chemical (sequential extraction) fractionation techniques were applied. Time differentiated sampling during rain events revealed that changes in the concentrations of soluble and particle bound phosphorus, and in the proportion of different PP phases, are due to

Nic Pacini; René Gächter

1999-01-01

390

Atmospheric Particulate Concentration Measured in an Urban Area Bandung  

NASA Astrophysics Data System (ADS)

- Atmospheric particulate concentration for total suspended particles (TSP) and for PM10 (particulate matter under 10 micron) was measured in Jalan Braga and ITB campus, Bandung. Six samples were collected over one- or two-day time periods using High Volume Sampler (HVS) for TSP and Low Volume Sampler (LVS) or Anderson Cascade Impactor for PM10. Samples were further analyzed to determine concentrations of metals, sulfate and nitrate. Concentration of NOx (NO and NO2) was also measured hourly and simultaneously during the sampling period. The results from this study show that the atmospheric particulate concentration in Jalan Braga for TSP ranged from 304.04 to 363.17, and for PM10 concentration ranged from 277.02 to 336.44 ?g/m3. The lead concentrations were 1.42-2.37 ?g/m3 in the TSP and 0.81-1.57 ?g/m3 in the PM10. The nitrate concentrations were 5.89-6.51 ?g/m3 and 2.27-3.45 ?g/m3 for the TSP and PM10, respectively. The hourly NOx concentration varied between 0.14-0.35 ppm. The total elements (metals, sulfate and nitrate) found in the samples contribute from 20 to 25% of the total particulate concentration.

Lestari, P.; Savitri

391

Analysis of Particulate Nitrate and Black Carbon Time Series .  

National Technical Information Service (NTIS)

The main objective of this research is to describe seasonal, weekly, and diurnal patterns in fine particulate BC and nitrate. Past studies have relied mainly on filter-based PM measurements as the starting point for time series analysis. These studies hav...

D. E. Millstein R. A. Harley S. V. Hering

2006-01-01

392

A ferroelectric photocatalyst for enhancing hydrogen evolution: polarized particulate suspension.  

PubMed

A particle-based photocatalyst with a permanent internal field prepared by a corona poling method is presented as a novel approach to enhance the hydrogen evolution reaction in a particulate-suspension system. Photocatalytic activity of K0.5Na0.5NbO3 was significantly improved by 7.4 times after the polarization. PMID:24752705

Park, Sangbaek; Lee, Chan Woo; Kang, Min-Gyu; Kim, Sanghyeon; Kim, Hae Jin; Kwon, Ji Eon; Park, Soo Young; Kang, Chong-Yun; Hong, Kug Sun; Nam, Ki Tae

2014-05-14

393

40 CFR 60.342 - Standard for particulate matter.  

Code of Federal Regulations, 2013 CFR

...owner or operator subject to the provisions of this subpart shall cause to be discharged into the atmosphere from any rotary lime kiln any gases which: (1) Contain particulate matter in excess of 0.30 kilogram per megagram (0.60...

2013-07-01

394

Filtering apparatus and methods of exchanging particulate filter materials  

Microsoft Academic Search

A method for exchanging particulate filter material in a gas cleaning plant is described. The method includes means defining a gas-permeable filter compartment within which said filter material is contained, said compartment being defined with a crude gas side and a clean gas side, and means for passing gas to be cleaned through said filter compartment from said crude gas

1980-01-01

395

MEASUREMENTS AND PARAMETERIZATION OF PARTICULATE SULFUR DRY DEPOSITION OVER GRASS  

EPA Science Inventory

Eddy-correlation measurements of particulate sulfur fluxes at the 1981 and 1982 Dry Deposition Intercomparison Experiments indicate a strong diurnal variation in deposition velocity (downward flux divided by concentration) at a height near 6 m. Values are considerably greater tha...

396

Photothermal Probe Beam Deflection Monitoring of Photochemical Particulate Production.  

National Technical Information Service (NTIS)

The photothermal probe beam deflection method was applied to monitor photochemical particulation induced by a pulsed N2 laser in a CS2 vapor. The signal indicates a fast heat release due to collisional relaxation of excited CS2, and a slow heat release th...

A. C. Tam H. Sontag P. Hess

1985-01-01

397

Electrically heated particulate filter diagnostic systems and methods  

DOEpatents

A system that diagnoses regeneration of an electrically heated particulate filter is provided. The system generally includes a grid module that diagnoses a fault of the grid based on at least one of a current signal and a voltage signal. A diagnostic module at least one of sets a fault status and generates a warning signal based on the fault of the grid.

Gonze, Eugene V [Pinckney, MI

2009-09-29

398

Diesel Engine Emissions of Particulates and Associated Organic Matter.  

National Technical Information Service (NTIS)

The objective of this phase of the CAPE-24 program was to develop and validate an analytical method for the analysis of PNA in diesel exhaust particulate. The first year of work included construction of a test engine facility, development of an analytical...

B. A. Petersen C. C. Chuang G. W. Kinzer P. W. Meehan R. M. Riggin

1980-01-01

399

RESPIRATORY DISEASE IN CHILDREN EXPOSED TO SULFUR OXIDES AND PARTICULATES  

EPA Science Inventory

Acute lower respiratory disease was surveyed by questionnaire among parents of 10,000 children aged 1 to 12 years in two Southeastern communities representing intermediate and high exposures to particulates and low sulfur dioxide levels. Morbidity reporting patterns with respect ...

400

Optical Method for Measuring the Mass Concentration of Particulate Emissions.  

National Technical Information Service (NTIS)

The objective of this study is to demonstrate the feasibility of an in-situ across-the-stack optical technique to measure the mass of particulate emissions from stationary sources. The technique uses small angle light scattering and transmittance to deter...

G. R. Markowski G. J. Woffinden D. S. Ensor

1976-01-01

401

Highly Predictive Structural Cell for Particulate Polymeric Composites  

Microsoft Academic Search

A unit cell of a specified shape under specified loading conditions has been offered for predicting some basic properties of particulate polymeric composites. The stress-strain state of the bonded and debonded cell has been calculated in the framework of the large deformation approach within a wide range of filler volume concentrations. Effective modulus-filler concentration curves have been predicted on the

V. V. Moshev; L. L. Kozhevnikova

1997-01-01

402

Pathogen recognition and development of particulate vaccines: Does size matter?  

Microsoft Academic Search

The use of particulate carriers holds great promise for the development of effective and affordable recombinant vaccines. Rational development requires a detailed understanding of particle up-take and processing mechanisms to target cellular pathways capable of stimulating the required immune responses safely. These mechanisms are in turn based on how the host has evolved to recognize and process pathogens. Pathogens, as

Sue D. Xiang; Anja Scholzen; Gabriela Minigo; Cassandra David; Vasso Apostolopoulos; Patricia L. Mottram; Magdalena Plebanski

2006-01-01

403

PARTICULATE CONTROL IN ENERGY PROCESSES: A STATUS REPORT  

EPA Science Inventory

This paper presents the significant findings of the 22 papers delivered at the Particulate Control in Energy Processes Symposium, held in San Francisco on May 12-14, 1976. Topics of discussion included use of low sulfur coals, electrostatic precipitators for low sulfur coal, bagh...

404

SAMPLING AND DATA HANDLING METHODS FOR INHALABLE PARTICULATE SAMPLING  

EPA Science Inventory

The report reviews the objectives of a research program on sampling and measuring particles in the inhalable particulate (IP) size range in emissions from stationary sources, and describes methods and equipment required. A computer technique was developed to analyze data on parti...

405

EFFECTS OF PARTICULATE AIR POLLUTION ON ASTHMATIC SUBJECTS  

EPA Science Inventory

While much remains to be understood, individuals with respiratory disease appear to be affected by high levels of air pollution as indicated by subjective reports, clinic and hospital visits, and morbidity. Suspended particulates make up a substantial part of urban air pollution,...

406

Modeling of suspended particulate matter transport in coastal areas  

Microsoft Academic Search

A three-dimensional suspended particulate matter (SPM) transport model, developed for North Sea scales (6 nm horizontal resolution), was improved and applied for a part of the North Frisian Wadden Sea with 100 m horizontal and 0.5 m vertical resolution. Satellite data were used to separate different SPM exchange processes and to derive appropriate model parameters. The model calculates distributions of

Andrey Pleskachevsky; Heinz Günther

2008-01-01

407

PROTON SCATTERING ANALYSIS FOR LIGHT ELEMENTS IN AIR PARTICULATE MATTER  

EPA Science Inventory

Proton scattering analysis has been developed to provide light element analyses as a complementary method to x-ray analysis. Samples of air particulate matter from both filter and impaction devices have been analyzed and time sequence and particle size information obtained. In co...

408

Size separation of particulates in a trommel screen system  

Microsoft Academic Search

This paper describes the design and testing of a trommel screen system for the separation of undersized particulates. The trommel screen system consisted of a cylindrical separation device that rotated to perform size separation. A series of experiments were carried out at room temperature to demonstrate the screening efficiency of this method under different operating conditions. The dynamic model and

Yi-Shun Chen; Shu-San Hsiau; Hsuan-Yi Lee; Yau-Pin Chyou; Chia-Jen Hsu

2010-01-01

409

Magnetic quantification of urban pollution sources in atmospheric particulate matter  

Microsoft Academic Search

A new method is presented for fast quantification of urban pollution sources in atmospheric particulate matter (PM). The remanent magnetization of PM samples collected in Switzerland at sites with different exposures to pollution sources is analysed. The coercivity distribution of each sample is calculated from detailed demagnetization curves of anhysteretic remanent magnetization (ARM) and is modelled using a linear combination

S. Spassov; R. Egli; F. Heller; D. K. Nourgaliev; J. Hannam

2004-01-01

410

Proposed SO/sub x/ and particulate standard. [Lead abstract  

SciTech Connect

Separate abstracts were prepared for 16 of 18 papers in this proceedings of a specialty conference held by the Air Pollution Control Association on the proposed SO/sub x/ and particulate standard. The other papers are duplicates and deal with acid rain and air pollution effects on vegetation. (KRM)

Frederick, E.R. (ed.)

1981-01-01

411

Systemic Microvascular Dysfunction and Inflammation after Pulmonary Particulate Matter Exposure  

Microsoft Academic Search

The epidemiologic association between pulmonary exposure to ambient particulate matter (PM) and cardiovascular dysfunction is well known, but the systemic mechanisms that drive this effect remain unclear. We have previously shown that acute pulmonary exposure to PM impairs or abolishes endothelium-dependent arteriolar dilation in the rat spinotrapezius muscle. The purpose of this study was to further characterize the effect of

Timothy R. Nurkiewicz; Dale W. Porter; Mark Barger; Lyndell Millecchia; K. Murali; K. Rao; Paul J. Marvar; Ann F. Hubbs; Vincent Castranova; Matthew A. Boegehold

2007-01-01

412

AN INDOOR AIR QUALITY MODEL FOR PARTICULATE MATTER  

EPA Science Inventory

Thye paper discusses an indoor air quality (IAQ) model for particulate matter (PM). The standard for PM < 2.5 micrometers in aerodynamic diameter (PM 2.5) proposed by the U.S. EPA has produced considerable interest in indoor exposures to PM. IAQ models provide a useful tool for...

413

Detector for particulate polycyclic aromatic hydrocarbons in water.  

PubMed

It is estimated that most polycyclic aromatic hydrocarbons (PAHs) in environmental water are not dissolved but rather in particulate form. Nevertheless, the currently available optical detectors are not suited for proper sampling of solid PAHs. A new setup for direct sampling and quantification of suspended particulate PAHs in water is suggested. It is based on a polymeric film that has the capability of dissolving PAH particulates, coupled to a traditional laser-induced fluorescence probe. Kinetics and performance of two sampling modes have been studied: bulk sampling, by immersing the probe into the water, and surface sampling, by laying the film on the water surface. The latter method has proved to be more sensitive; however, it is diffusion-limited. Linear calibration plots have provided quantification over a wide concentration range with detection limits in the ppb range (these could be improved by using a modified probe). The effects due to other particulates in water have been studied and only little interferences have been observed. The possibility of analysis of PAH mixtures has been addressed and it has been concluded that multivariate analysis is needed. PMID:15789244

Levinson, Jane; Sluszny, Chanan; Yasman, Yakov; Bulatov, Valery; Schechter, Israel

2005-04-01

414

Ultrafine ambient particulate matter enhances cardiac ischemia and reperfusion injury  

EPA Science Inventory

Epidemiological studies have demonstrated a consistent link between exposure to ambient particulate air pollutant (PM) and the incidence of cardiovascular morbidity and mortality. The present study was designed to evaluate the cardiac effects of ambient PM. Mice were exposed to 1...

415

INVESTIGATING PREFERENTIAL DISSOLUTION OF LEAD FROM SOLDER PARTICULATES  

EPA Science Inventory

Water samples taken in a building corrosion control study having high lead levels often contained particulate material at the bottom of the acid-preserved sample bottles. canning electron microscope analysis of the particles revealed the presence of tin and absence of lead, indic...

416

Mechanics of particulate composites with glassy polymer binders in compression.  

PubMed

Whether used as structural components in design or matrix materials for composites, the mechanical properties of polymers are increasingly important. The compressive response of extruded polymethyl methacrylate (PMMA) rod with aligned polymer chains and Al-Ni-PMMA particulate composites are investigated across a range of strain rates and temperatures. The particulate composites were prepared using an injection-moulding technique resulting in highly anisotropic microstructures. The mechanics of these materials are discussed in the light of theories of deformation for glassy polymers. The experimental data from this study are compared with PMMA results from the literature as well as epoxy-based composites with identical particulates. The PMMA exhibited the expected strain rate and temperature dependence and brittle failure was observed at the highest strain rates and lowest temperatures. The Al-Ni-PMMA composites were found to have similar stress-strain response to the PMMA with reduced strain softening after yield. Increasing volume fraction of particulates in the composite resulted in decreased strength. PMID:24711495

Jordan, J L; Spowart, J E; Kendall, M J; Woodworth, B; Siviour, C R

2014-01-01

417

REGIONAL PARTICULATE MODEL - 1. MODEL DESCRIPTION AND PRELIMINARY RESULTS  

EPA Science Inventory

The gas-phase chemistry and transport mechanisms of the Regional Acid Deposition Model have been modified to create the Regional Particulate Model, a three-dimensional Eulerian model that simulates the chemistry, transport, and dynamics of sulfuric acid aerosol resulting from pri...

418

CAPSULE REPORT: BAHCO FLUE GAS DESULFURIZATION AND PARTICULATE REMOVAL SYSTEM  

EPA Science Inventory

This capsule report describes a Research-Cottrell/Bahco scrubber module for sulfur dioxide and particulate emission control located at the central heat plant of Rickenbacker Air Force Base. he report also describes flue gas desulfurization technology using any fuel, including hig...

419

ASSESSMENT OF HUMAN EXPOSURE TO AMBIENT PARTICULATE MATTER.  

EPA Science Inventory

Recent epidemiological studies have consistently shown that the acute mortality effects of high concentrations of ambient particulate matter (PM), documented in historic air pollution episodes, may also be occurring at the low to moderate concentrations of ambient PM found in mod...

420

A predictive model for the mechanical behavior of particulate composites  

Microsoft Academic Search

A method for predicting the stress-strain and volumetric behavior of particulate composites from constituent properties has been developed. These materials exhibit a phenomenon known as debonding in which filler particles pull away from the matrix material, causing ellipsoidal vacuoles to form about each particle. An energy balance derived from the first law of thermodynamics calculates critical strain values at which

1989-01-01

421

EFFECTS OF SELECTED WATERBORNE PARTICULATES ON CELLULAR AND MOLECULAR PARAMETERS  

EPA Science Inventory

Embryonic cultures were used to compare the effects of six particulate samples, some filtered directly from drinking water on a cellular, biochemical and molecular basis. Cytotoxicity was exhibited in human cells for all agents tested at the highest concentration used (10 mg/ml)....

422

Storm effects on particulate food resources on an intertidal sandflat  

Microsoft Academic Search

The influence of storms on particulate food resources on an intertidal sandflat (Cape Henlopen, Delaware, USA) was investigated by contrasting measurements taken during calm conditions and storm conditions. Storms exhibited elevated fluid velocities dominated by an oscillatory component, doubled seston concentrations increasing toward the bed and increased sediment transport rates. We also measured the concentration of sedimentary protein and chlorophyll

Michael J. Bock; Douglas C. Miller

1995-01-01

423

METHODS FOR EFFECTIVE FLUIDIZATION OF PARTICULATE FOOD MATERIALS  

Microsoft Academic Search

Depending on the size and shape of the materials, methods employed to achieve effective fluidization during fluid bed drying varies from use of simple hole distributors for small, light weight materials to special techniques for larger and\\/or moist materials. This paper reviews common air distributors used in fluidized bed drying of food particulates. Also it reviews special methods of fluidizing

Wijitha Senadeera; Bhesh R. Bhandari; Gordon Young; Bandu Wijesinghe

2000-01-01

424

Microwave mode shifting antenna system for regenerating particulate filters  

Microsoft Academic Search

A regeneration system comprises a particulate matter (PM) filter including a microwave energy absorbing surface, and an antenna system comprising N antennas and an antenna driver module that sequentially drives the antenna system in a plurality of transverse modes of the antenna system to heat selected portions of the microwave absorbing surface to regenerate the PM filter, where N is

Eugene V. Gonze; Paratore Jr. Michael J; Kevin W. Kirby; Amanda Phelps; Daniel J. Gregoire

2011-01-01

425

Wireless zoned particulate matter filter regeneration control system  

Microsoft Academic Search

An assembly includes a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and multiple zones. An absorbing layer absorbs microwave energy in one of N frequency ranges and is arranged with the upstream end. N is an integer. A frequency selective filter has M frequency selective segments and receives microwave energy in

Eugene V. Gonze; Paratore Jr. Michael J; Kevin W. Kirby; Amanda Phelps; Daniel J. Gregoire

2011-01-01

426

Research for Particulate Control. EPA's Mobile Test Vans.  

National Technical Information Service (NTIS)

This report discusses EPA's mobile vans and their use in on-site aerosol monitoring. It contains a complete explanation of what is involved in hosting a mobile particulate control van at a plant, including specifications for installation and operation of ...

1979-01-01

427

Increased Particulate Air Pollution and the Triggering of Myocardial Infarction  

Microsoft Academic Search

Background—Elevated concentrations of ambient particulate air pollution have been associated with increased hospital admissions for cardiovascular disease. Whether high concentrations of ambient particles can trigger the onset of acute myocardial infarction (MI), however, remains unknown. Methods and Results—We interviewed 772 patients with MI in the greater Boston area between January 1995 and May 1996 as part of the Determinants of

Annette Peters; Douglas W. Dockery; James E. Muller; Murray A. Mittleman

2001-01-01

428

Health Effects of Fine Particulate Air Pollution: Lines that Connect  

Microsoft Academic Search

Efforts to understand and mitigate the health effects of particulate matter (PM) air pollution have a rich and interesting history. This review focuses on six substantial lines of research that have been pursued since 1997 that have helped elucidate our understanding about the effects of PM on human health. There has been substantial progress in the evaluation of PM health

C. Arden Pope III; Douglas W. Dockery; Joe L. Mauderly; Daniel L. Costa; Ronald E. Wyzga; Sverre Vedal; George M. Hidy; Sam L. Altshuler; David Marrack; Jon M. Heuss; George T. Wolff

2006-01-01

429

Rotary device for removing particulates from a gas stream  

NASA Technical Reports Server (NTRS)

A rotary particulate separator for removing particulates from a pressurized gas stream such as that emanating from a reactor vessel is disclosed which precharges the particles in the gas stream, and then utilizes the charge on the particles to induce them from the main flow path through an airblock and into the rotary particulate separator. The rotor of the rotary particulate separator has polarized plates which use a first charge opposite that on the charged particles to attract the particles as they enter the rotation chamber, and then use a second charge of the same polarity as the charge on the charged particles to release the particles into a control gas flow vortex which draws the particles radially inwardly into an exit aperture contained in the center of one of the rotor segments and out from the device. Pressure letdown devices are used to drop the pressure of both the control gas flow exiting the separator with the particles and the cleaned gas stream.

Collins, Jr., Earl R. (Inventor)

1992-01-01

430

Fatty Acids in Surface Particulate Matter from the North Atlantic.  

National Technical Information Service (NTIS)

The fatty acid composition of particulate matter from surface waters in the North Atlantic has been investigated. A high proportion is long-chain polyunsaturated acids, typical of a marine origin. The low relative abundance of iso and anteiso 15-carbon ac...

D. M. Schultz J. G. Quinn

1972-01-01

431

Mutagenicity of particulates from the laboratory combustion of plastics.  

PubMed

Carcinogenic polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (nitro-PAHs) have been identified in airborne particulate organic matter extracts. The pollutant sources were generally contributed by motor vehicles and industrial activity. Massive quantities of urban solid wastes, containing plastic materials such as PVC, PET, PS, and PE, burnt in the open air in local garbage dumps are frequently found in developing countries. In this study, the smog particulates from the combustion of these synthetic polymers were produced in a laboratory combustion chamber. The mutagenicity of acetone extracts from the smog particulates was evaluated with Salmonella typhimurium TA98 and TA100 in the presence and absence of S9 mix. Four samples in TA98 exhibited higher mutagenicity than those in TA100. The greatest mutagenicity was observed from the extracts of particulates from combustion of PVC followed by that of PS, PET, and PE. To determine the major mutagenic compounds in these samples, mutagens were partially purified through TLC and their mutagenicity was monitored with TA98. 1-NP and DNPs in the above samples were also determined by HPLC. The amounts of 1-NP and DNPs generally corresponded with their mutagenicity. Higher levels of 1-NP and DNPs were generated from the combustion of PVC, PET, and PS. The combustion of synthetic polymer wastes might be responsible for the presence of high levels of 1-NP and DNPs in Taiwan urban air. PMID:7700277

Lee, H; Wang, L; Shih, J F

1995-03-01

432

Developing Meaningful Measures and Guidelines for Particulates in Aquatic Ecosystems  

NASA Astrophysics Data System (ADS)

Managing global water resources is one of the greatest challenges of the 21st Century. It is a resource that is under growing pressure as global populations rise and the natural supply, in the form of precipitation, is becoming increasingly variable and uncertain with climate change. It is therefore essential that water resources (surface and groundwaters) are managed sustainably in terms of both their quantity and quality. One of the most common causes for the impairment of water quality in surface waters and groundwaters is the presence of particulate matter. Particulate matter, from nano-scale particles and colloids to silt-sized sediments, can have a range of detrimental effects on water resources, from aesthetic issues and higher costs of water treatment, to a decline in the fisheries resource and serious ecological degradation. However at present, there is a poor understanding of the particulate conditions that water quality managers should aim to achieve in order to support good ecological status in different environments. There is also currently a general lack of rigour and standardisation in measurements of particulate matter in aquatic ecosystems, which in turn limits our understanding of the effects of these particles, and importantly, limits our ability to guide effective remediation. This poster describes a research approach that is currently being developed in the UK to address these issues; supporting (1) the development of ecosystem-specific water quality guidelines for particulate matter, and (2) the innovation of more advanced monitoring technologies for particulate matter in aquatic environments. The research project will utilise an established network of 13 reference condition sites (i.e. sites that have minimal anthropogenic disturbance) that contain distinct aquatic communities and are located in contrasting environment types. Hydrological and biological monitoring will be carried-out concurrently with analysis of the physical and geochemical properties of the particulates in each environment. Monitoring of the dynamics of these parameters will continue for 3.5 years, providing a medium to long-term record that can be used to develop statistical models and inform both water resource policy and technological innovation.

Bilotta, G. S.; Harrison, C.; Joyce, C.; Peacock, C.

2010-12-01

433

Applicability of the Mass Concentration Standards for Particulate Matter in Alaskan Areas  

Microsoft Academic Search

High particulate matter concentrations were measured in several communities in Alaska using high volume air samplers. Because of these measurements, Anchorage and Fairbanks have been classified Priority 1 for particulate matter. To define and better understand the meaning of particulate measurements in Alaska, the Alaska Department of Environmental Conservation, in conjunction with local agencies, collected and evaluated air quality data

Timothy M. Gilmore; Thomas R. Hanna

1975-01-01

434

Electrically heated particulate filter regeneration methods and systems for hybrid vehicles  

DOEpatents

A control system for controlling regeneration of a particulate filter for a hybrid vehicle is provided. The system generally includes a regeneration module that controls current to the particulate filter to initiate regeneration. An engine control module controls operation of an engine of the hybrid vehicle based on the control of the current to the particulate filter.

Gonze, Eugene V. (Pinckney, MI); Paratore, Jr., Michael J. (Howell, MI)

2010-10-12

435

Association of Heart Rate Variability With Occupational and Environmental Exposure to Particulate Air Pollution  

Microsoft Academic Search

Background—Airborne particulate matter has been linked to excess morbidity and mortality. Recent attention has focused on the effects of particulate exposure on cardiac autonomic control. Inhaled particulates may affect the autonomic nervous system either directly, by eliciting a sympathetic stress response, or indirectly, through inflammatory cytokines produced in the lungs and released into the circulation. Methods and Results—This longitudinal study

Shannon R. Magari; Russ Hauser; Joel Schwartz; Paige L. Williams; Thomas J. Smith; David C. Christiani

2001-01-01

436

Particulation in jets from free-form hemispherical shaped charges with copper liners  

Microsoft Academic Search

Particulation in free-form hemispherical shaped charge jets is considerably different from that in conical shaped charge jets. From the analysis of the particulation data for 23 experiments covering ten free-form hemi designs with copper liners, it is concluded that jets with higher convergence pressures have delayed particulation, sometimes by as much as a factor of two. Breakup is also found

S. C. Simonson; L. C. Jr. Haselman; R. D. Breithaupt

1995-01-01

437

Percolation segregation in multi-size and multi-component particulate mixtures: Measurement, sampling, and modeling  

Microsoft Academic Search

Particulate materials are routinely handled in large quantities by industries such as, agriculture, electronic, ceramic, chemical, cosmetic, fertilizer, food, nutraceutical, pharmaceutical, power, and powder metallurgy. These industries encounter segregation due to the difference in physical and mechanical properties of particulates. The general goal of this research was to study percolation segregation in multi-size and multi-component particulate mixtures, especially measurement, sampling,

Anjani K. Jha

2008-01-01

438

Experimental Study on Particulate Emissions of a Methanol Fumigated Diesel Engine Equipped with Diesel Oxidation Catalyst  

Microsoft Academic Search

In this article, the effects of fumigation methanol, diesel oxidation catalyst, and engine operation parameters (engine load and engine speed) on diesel smoke opacity, particulate mass concentration, particulate number concentration and the soluble organic fraction (SOF) in the particulate were investigated at certain selected operation conditions. Experiments were performed on a 4-cylinder direct injection diesel engine operating at three engine

Z. H. Zhang; C. S. Cheung; T. L. Chan; C. D. Yao

2011-01-01

439

Forest vegetation as a sink for atmospheric particulates: Quantitative studies in rain and dry deposition  

Microsoft Academic Search

Radionuclides in the atmosphere are associated with nonradioactive air particulates and hence serve to trace the fluxes of air particulates to various surfaces. Natural and artificial radioactivities found in the atmosphere have been measured in vegetation for 10 years to elucidate some of the mechanisms of acquirement by forest trees of atmospheric particulates. Whole tree analysis, in conjunction with soil

Irving J. Russell; Carl E. Choquette; Shih-Lieh Fang; William P. Dundulis; Andrew A. Pao; Alexander A. P. Pszenny

1981-01-01

440

Particulate emboli capture by an intra-aortic filter device during cardiac surgery  

Microsoft Academic Search

Objective: Particulate embolization is associated with neurologic morbidity after cardiac surgery. Crossclamp manipulation has been identified as the single most significant cause of particulate emboli release during cardiac surgery. A new intra-aortic filtration method has been assessed with regard to its safety and its ability to capture particulate emboli before they enter the central circulation. Methods: Patients undergoing cardiac surgery

Hermann Reichenspurner; Jose A. Navia; Gerald Berry; Robert C. Robbins; Denise Barbut; Jeffrey P. Gold; Bruno Reichart

2000-01-01

441

Kinetics of ceramic particulate penetration into spray atomized metallic droplet at variable penetration depth  

Microsoft Academic Search

The present study provides insight into the physical interactions that take place when an injected ceramic particulate collides with an atomized metallic droplet during spray atomization and deposition processing of particulate reinforced metal matrix composites. A model is developed to predict the extent of penetration for a given particulate velocity, and the critical velocity for complete penetration. In the model,

J. Zhang; Y. Wu; E. J. Lavernia

1994-01-01

442

PARTICULATE EMISSIONS AND CONTROL IN FLUIDIZED-BED COMBUSTION: MODELING AND PARAMETRIC PERFORMANCE  

EPA Science Inventory

The report discusses a model, developed to describe the physical characteristics of the particulates emitted from fluidized-bed combustion (FBC) systems and to evaluate data on FBC particulate control systems. The model, which describes the particulate emissions profile from FBC,...

443

Monitoring of PM10 and PM2.5 around primary particulate anthropogenic emission sources  

Microsoft Academic Search

Investigations on the monitoring of ambient air levels of atmospheric particulates were developed around a large source of primary anthropogenic particulate emissions: the industrial ceramic area in the province of Castelló (Eastern Spain). Although these primary particulate emissions have a coarse grain-size distribution, the atmospheric transport dominated by the breeze circulation accounts for a grain-size segregation, which results in ambient

Xavier Querol; Andrés Alastuey; Sergio Rodriguez; Felicià Plana; Enrique Mantilla; Carmen R Ruiz

2001-01-01

444

Comparison of Polycyclic Aromatic Hydrocarbons and Nitropolycyclic Aromatic Hydrocarbons in Airborne and Automobile Exhaust Particulates  

Microsoft Academic Search

Polycyclic aromatic hydrocarbons (PAH) and nitropolycyclic aromatic hydrocarbons (NPAH) in airborne particulates collected simultaneously at downtown and suburban sites and in exhaust particulates from diesel and gasoline engine vehicles were determined. The mean concentrations of all compounds in the atmosphere were lower at the suburban site. The differences between the two sites were smaller in airborne particulates than in the

Kazuichi Hayakawa; Tsuyoshi Murahashi; Kazuhiko Akutsu; Tetsuo Kanda; Ning Tang; Hitoshi Kakimoto; Akira Toriba; Ryoichi Kizu

2000-01-01

445

A new technology for the reduction of particulate matter from diesel engines in ships  

Microsoft Academic Search

In this thesis the focus is on the particulate matter reduction of ships, as ships contribute significantly to the particulate matter concentration in ambient air. Because the fuel of sea ships contains a lot of ash, the emitted particulate matter will also contain a lot of ash. In car and truck applications the soot filters are cleaned by burning the

G. L. M. A. Van Rens

2008-01-01

446

Corrosion and degradation of ceramic particulate filters in direct coal-fired turbine applications  

SciTech Connect

High-temperature ceramic filters show considerable promise for efficient particulate removal from coal combustion systems. Advanced coal utilization processes such as direct coal-fired turbines require particulate-free gas for successful operation. This paper describes the various ceramic particulate filters under development and reviews the degradation mechanisms expected when operated in coal combustion systems.

Sawyer, J. (Acurex Corp., Mountain View, CA (US)); Vass, R.J.; Brown, N.R.; Brown, J.J. (Center for Advanced Ceramic Materials, CIT TDC, Virginai Polytechnic Inst. and State Univ., Blacksburg, VA (US))

1991-10-01

447

In-situ optical measurement of additive effects on particulates in a sooting diffusion flame  

Microsoft Academic Search

The size, number density and volume fraction in a laminar diffusion flame, with or without metallic additives which alter particulate properties, can be determined through the Mie scattering of visible light by soot particulates. Data are presently obtained for the alkali chlorides, which were aspirated in propane\\/oxygen flames diluted with nitrogen and whose soot particulate properties were evaluated from scattered

P. A. Bonczyk

1983-01-01

448

Generation of hydroxyl radicals by urban suspended particulate air matter. The role of iron ions  

Microsoft Academic Search

Recent epidemiologic studies showed statistical associations between particulate air pollution in urban areas and increased morbidity and mortality, even at levels well within current national air quality standards. Inhalable particulate matter (PM10) can penetrate into the lower airways where they can cause acute and chronic lung injury by generating toxic oxygen free radicals. We tested inhalable total suspended particulates (TSP)

Athanasios Valavanidis; Anastasia Salika; Anna Theodoropoulou

2000-01-01

449

HUMAL ALVEOLAR MACROPHAGE RESPONSES TO AIR POLLUTION PARTICULATES ARE ASSOCIATED WITH INSOLUBLE OCMPONENTS OF COARSE MATERIAL, INCLUDING PARTICULATE ENDOTOXIN  

EPA Science Inventory

Inhalation of particulate matter in the ambient air has been shown to cause pulmonary morbidity and exacerbate asthma. Alveolar macrophage (AM) are essential for effective removal of inhaled particles and microbes in the lower airways. While some particles minimally effect AM...

450

Particulate matter < 10 ?m (PM 10) and total suspended particulates (TSP) in urban, rural and alpine air in Switzerland  

Microsoft Academic Search

Ambient concentrations of particulate matter of less than 10 ?m aerodynamic diameter were measured in Switzerland for a 1 yr period in 1993 at a dozen urban, rural and alpine sites. PM10 concentrations ranged between 10 ?g m?3 (alpine) and 33 ?g m?3 (urban). Highest concentrations were found at Lugano, in the south of the Alps, and in urban sites

Ch. Monn; O. Braendli; G. Schaeppi; Ch. Schindler; U. Ackermann-Liebrich; Ph. Leuenberger

1995-01-01

451

Removal of Sulfur from Natural Gas to Reduce Particulate Matter Emission from a Turbine Engine  

NASA Astrophysics Data System (ADS)

The present work investigates the effect of natural gas fuel sulfur on particulate emissions from stationary gas turbine engines used for electricity generation. Fuel sulfur from standard line gas was scrubbed using a system of fluidized reactor beds containing a specially designed activated carbon purpose built for sulfur absorption. A sulfur injection system using sonic orifices was designed and constructed to inject methyl mercaptan into the scrubbed gas stream at varying concentrations. Using these systems, particulate emissions created by various fuel sulfur levels between 0 and 8.3 ppmv were investigated. Particulate samples were collected from a Capstone C65 microturbine generator system using a Horiba MDLT-1302TA micro dilution tunnel and analyzed using a Horiba MEXA-1370PM particulate analyzer. In addition, ambient air samples were collected to determine incoming particulate levels in the combustion air. The Capstone C65 engine air filter was also tested for particulate removal efficiency by sampling downstream of the filter. To further differentiate the particulate entering the engine in the combustion air from particulate being emitted from the exhaust stack, two high efficiency HEPA filters were installed to eliminate a large portion of incoming particulate. Variable fuel sulfur testing showed that there was a strong correlation between total particulate emission factor and fuel sulfur concentration. Using eleven variable sulfur tests, it was determined that an increase of 1 ppmv fuel sulfur will produce an increase of approximately 3.2 microg/m3 total particulate. Also, the correlation also predicted that, for this particular engine, the total particulate emission factor for zero fuel sulfur was approximately 19.1 microg/m3. With the EC and OC data removed, the correlation became 3.1 microg/m3 of sulfur particulate produced for each ppmv of fuel sulfur. The correlation also predicted that with no fuel sulfur present, 6.6 microg/m3 of particulate will be produced by sulfur passing through the engine air filter.

Spang, Brent Loren

452

Assessments of pulmonary macrophage clearance responses to inhaled particulates.  

PubMed

An integrated bioassay program is being developed to evaluate the toxicity of inhaled particulate materials. The multi-disciplined approach combines studies on lung clearance mechanisms with pulmonary macrophage functional assessments based on cellular biology, biochemical and cytochemical evaluations on lung specimens from exposed animals. To validate this method, animals were exposed to asbestos, iron-treated asbestos, fiberglass, Mt. St. Helens ash or carbonyl iron particles. Deposition patterns, macrophage migration and phagocytosis were monitored in vivo at selected time periods after exposure. Our results showed that chemotactic factor generation by particles in vitro correlated with the corresponding macrophage recruitment responses in vivo. In addition, macrophage morphologic and functional characteristics were evaluated following exposures to aerosolized dusts. Our results suggest that scanning electron microscopy (SEM) techniques for investigating particle deposition and macrophage clearance provide an important component for evaluating the toxicity of inhaled particulate materials. PMID:3399846

Warheit, D B; Hartsky, M A

1988-06-01

453

Reduction of particulate carryover from a pressurized fluidized bed  

NASA Technical Reports Server (NTRS)

A bench-scale pressurized fluidized bed combustor (PFBC) constructed with a conical shape to reduce the particulate carryover is examined. The combustor was fed coal and limestone with the coal to air ratio varying from 0.033 to 0.098 (all lean) and the coal to limestone ratio varying from 0.06 to 0.36. Two cone angles were used and it is shown that the average particulate carryover of 2.5 grains/SCF is appreciably less than cylindrical fluidized bed combustors. In addition the carryover was correlated by multiple regression analysis to yield the dependence on bed depth and hence the collection efficiency, which was 20%. Finally, a comparison with a model indicated that the exhaust port may be below the transport disengaging height for most of the tests showing that further improvements could be achieved by increasing the freeboard height of the exhaust port above the bed.

Patch, R. W.

1979-01-01

454

Mitigation of comminution effects of explosives by particulate materials  

NASA Astrophysics Data System (ADS)

Brisance effects were measured by the crushing of a copper cone by the stress wave set up by an explosive. The crushing effect was mitigated by the presence of layers of particulate material. The mitigation was principally achieved by the energy used in consolidating the particulate material. This was a function of the particle size of the sand used and was greatest for a fine-grained sand. For military explosives relative brisance effects measured by cone crushing were similar to those calculated by formulas derived from analysis of the chemistry of the explosive, but results for the lower detonation velocity nitromethane explosive gave values somewhat higher than those derived from chemistry-based formulas.

Edwards, M. R.; Palmer, M. E.

2003-03-01

455

Solid-particle erosion of aluminum/particulate ceramic composites  

SciTech Connect

Impact erosion of 2014 aluminum, 2014 aluminum + 20 vol % particulate silicon carbide, and 2014 aluminum + 20 vol % particulate aluminum oxide has been studied at room temperature. The alloys were tested in the as-received and heat-treated conditions. Experiments were conducted with aluminum oxide abrasive in vacuum in a slinger-type apparatus over a range of abrasive size, velocity, and angle of impact. Erosion rates were influenced by reinforcement and heat treatment. Reduced ductility, both overall and local, attributed to reinforcement or heat treatment, caused, under most conditions, more rapid erosion of the composites. The data suggest that erosion rate can be minimized by proper microstructural control, involving reducing reinforcement segregation and the amount of intermetallic compounds. 37 refs., 7 figs.

Goretta, K.C.; Wu, W.; Routbort, J.L. (Argonne National Lab., IL (USA)); Rohatgi, P.K. (Wisconsin Univ., Milwaukee, WI (USA))

1990-06-01

456

High diversity of fungi in air particulate matter  

PubMed Central

Fungal spores can account for large proportions of air particulate matter, and they may potentially influence the hydrological cycle and climate as nuclei for water droplets and ice crystals in clouds, fog, and precipitation. Moreover, some fungi are major pathogens and allergens. The diversity of airborne fungi is, however, not well-known. By DNA analysis we found pronounced differences in the relative abundance and seasonal cycles of various groups of fungi in coarse and fine particulate matter, with more plant pathogens in the coarse fraction and more human pathogens and allergens in the respirable fine particle fraction (<3 ?m). Moreover, the ratio of Basidiomycota to Ascomycota was found to be much higher than previously assumed, which might also apply to the biosphere.

Frohlich-Nowoisky, Janine; Pickersgill, Daniel A.; Despres, Viviane R.; Poschl, Ulrich

2009-01-01

457

Perspectives on Localized Corrosion in Thin Layers of Particulate  

SciTech Connect

The requirements for the initiation and propagation of localized corrosion are reviewed, and the stability criteria for sustained localized corrosion are discussed. A conceptual framework is applied to a specific scenario of a hot metal surface covered by a thin layer of particulate containing dissolvable salts in the presence of air of limited humidity. A number of processes are demonstrated to affect the crevice corrosion propagation, stifling and arrest. Contributions of the particulate layer properties, the anode, cathode and coupled processes are identified, showing that any of these can control localized corrosion propagation. Whether stifling or arrest occur will depend upon the material and environmental conditions for a given case. The findings add to the technical basis for the analysis of localized corrosion by a decision tree methodology. (authors)

Payer, Joe H. [Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Ave., 404 White Bldg., Cleveland, OH, 44106 (United States); Kelly, Robert G. [Materials Science and Engineering, University of Virginia, 116 Engineer's Way, Materials Science Building 323, PO Box 400745, Charlottesville, VA, 22904-4745 (United States)

2007-07-01

458

Gaseous and particulate emissions from a DC arc melter.  

PubMed

Tests treating soils contaminated with metal compounds and radionuclide surrogates were conducted in a DC arc melter. The soil melted, and glassy or ceramic waste forms with a separate metal phase were produced. Tests were run in the melter plenum with either air or N2 purge gases. In addition to nitrogen, the primary emissions of gases were CO2, CO, oxygen, methane, and oxides of nitrogen (NO(x)). Although the gas flow through the melter was low, the particulate concentrations ranged from 32 to 145 g/m3. Cerium, a nonradioactive surrogate for plutonium and uranium, was not enriched in the particulate matter (PM). The PM was enriched in cesium and highly enriched in lead. PMID:12568249

Overcamp, Thomas J; Speer, Matthew P; Griner, Stewart J; Cash, Douglas M

2003-01-01

459

Laser doppler techniques for sizing particulate pollutants and therapeutic aerosols  

NASA Astrophysics Data System (ADS)

A particle size analyzer based on laser Doppler velocimetry has been developed for measuring, in real time, the aerodynamic size distribution of aerosol particulates in the respirable range 0.1 to 10.0 ?m in diameter. The instrument, a single particle aerodynamic relaxation time analyzer, measures the aerodynamic relaxation time of individual suspended particles and droplets without removing the particulates from their aerosol phase. Measurements can be made at a maximum count rate of 200 particles/sec, although coincidence error restricts the count rate to a lower limit. The size resolution is within +/-5% of the measured aerodynamic diameter. Currently, three prototype SPART analyzers are being used for: (1) studying aerodynamic size distribution and lung retention of therapeutic aerosols, (2) measuring fractional efficiency of electrostatic precipitators as a function of size and electrical resistivity of flyash particles, and (3) characterizing atmospheric and household aerosols.

Mazumder, M. K.; Hiller, F. C.; Ware, R. E.; Wilson, J. D.; McLeod, P. C.

1980-12-01

460

High efficiency particulate removal with sintered metal filters  

NASA Astrophysics Data System (ADS)

Because of their particle removal efficiencies and durability, sintered metal filters have been chosen for high efficiency particulate air (HEPA) filter protection in the off gas treatment system for a proposed transuranic waste treatment facility. Process evaluation of sintered metal filters indicated a lack of sufficient process design data to ensure trouble free operation. Subsequence pilot scale testing was performed with flyash as the test particulate. The test results showed that the sintered metal filters can have an efficiency greater than 0.9999999 for the specific test conditions used. Stable pressure drop characteristics were observed in pulsed and reversed flow blowback modes of operation. Over 4900 hours of operation were obtained with operating conditions ranging up to approximately 90 C and 24 vol % water vapor in the gas stream.

Kirstein, B. E.; Paplawsky, W. J.; Pence, D. T.; Hedahl, T. G.

461

Sinking velocity of particulate radiocesium in the northwestern North Pacific  

NASA Astrophysics Data System (ADS)

particles (SP) were collected by time series sediment traps at two depths in the northwestern Pacific before and after the Fukushima Daiichi Nuclear Power Plant accident, and accident-derived particulate radiocesium was measured. Radiocesium (137Cs) was first detected at 500 m (4810 m) about 2 weeks (1 month) after the accident. 137Cs of SP collected over 1 year revealed that the time lag between two depths was larger than that for the first 137Cs detection (about 2 weeks). We estimated the transient sinking velocity (SV) from the cumulative temporal 137Cs flux and the time lags at the two depths. Although the SV of SP collected in very early period was large, the estimated SV of most particulate 137Cs (about 80%) was about 50 m d-1. Based on comparison of 137Cs concentration in total SP with that in SP without organic materials, we suspect that most of the 137Cs was likely incorporated into aluminosilicates.

Honda, Makio C.; Kawakami, Hajime

2014-06-01

462

Design characteristics for facilities which process hazardous particulate  

SciTech Connect

Los Alamos National Laboratory is establishing a research and processing capability for beryllium. The unique properties of beryllium, including light weight, rigidity, thermal conductivity, heat capacity, and nuclear properties make it critical to a number of US defense and aerospace programs. Concomitant with the unique engineering properties are the health hazards associated with processing beryllium in a particulate form and the potential for worker inhalation of aerosolized beryllium. Beryllium has the lowest airborne standard for worker protection compared to all other nonradioactive metals by more than an order of magnitude. This paper describes the design characteristics of the new beryllium facility at Los Alamos as they relate to protection of the workforce. Design characteristics to be reviewed include; facility layout, support systems to minimize aerosol exposure and spread, and detailed review of the ventilation system design for general room air cleanliness and extraction of particulate at the source.

Abeln, S.P.; Creek, K.; Salisbury, S.

1998-12-01

463

Estimation of the Monthly Average Ratios of Organic Mass to Organic Carbon for Fine Particulate Matter at an Urban Site  

Microsoft Academic Search

Two independent methods are used to estimate the seasonality of the ratio of fine particulate organic matter (OM) to fine particulate organic carbon (OC) for atmospheric particulate matter collected at the St. Louis—Midwest Supersite. The first method assumes that all of the fine particulate matter mass that cannot be attributed to sulfate ion, nitrate ion, ammonium ion, elemental carbon and

Min-Suk Bae; James J. Schauer; Jay R. Turner

2006-01-01

464

Comparison of Strategies for the Measurement of Mass Emissions from Diesel Engines Emitting Ultra-Low Levels of Particulate Matter  

Microsoft Academic Search

Regulatory methods for the measurement of particulate matter (PM) mass emissions have traditionally been gravimetric. Modern diesel engines equipped with aftertreatment systems, especially Diesel Particulate Filters (DPFs), however, emit much smaller amounts of particulate matter as compared to traditional diesel engines and emit particulate matter with variable compositions. These changes have led to difficulties in measuring PM emissions rates from

Z. Gerald Liu; Victoria N. Vasys; Melissa E. Dettmann; James J. Schauer; David B. Kittelson; Jacob Swanson

2009-01-01

465

Determination of Levoglucosan in Particulate Matter Reference Materials  

Microsoft Academic Search

Source identification is critical for the effective management of air pollution. The ratio of levoglucosan (1,6-anhydro-? -D-glucose) to organic carbon has been used to identify and quantify the contribution of biomass combustion to the organic carbon content in aerosols. Therefore, accurate levoglucosan measurements in particulate matter are important. This study determined levoglucosan concentrations in urban dust Standard Reference Materials (SRMs)

Randolph K. Larsen III; Michele M. Schantz; Stephen A. Wise

2006-01-01

466

Microwave mode shifting antenna system for regenerating particulate filters  

DOEpatents

A regeneration system comprises a particulate matter (PM) filter including a microwave energy absorbing surface, and an antenna system comprising N antennas and an antenna driver module that sequentially drives the antenna system in a plurality of transverse modes of the antenna system to heat selected portions of the microwave absorbing surface to regenerate the PM filter, where N is an integer greater than one. The transverse modes may include transverse electric (TE) and/or transverse magnetic (TM) modes.

Gonze, Eugene V. (Pinckney, MI) [Pinckney, MI; Paratore, Jr., Michael J. (Howell, MI); Kirby, Kevin W. (Calabasas Hills, CA) [Calabasas Hills, CA; Phelps, Amanda (Malibu, CA) [Malibu, CA; Gregoire, Daniel J. (Thousand Oaks, CA) [Thousand Oaks, CA

2011-04-26

467

Ultrafine Particulate Pollutants Induce Oxidative Stress and Mitochondrial Damage  

Microsoft Academic Search

The objectives of this study were to determine whether differences in the size and composition of coarse (2.5-10 µm), fine (< 2.5 µm), and ultrafine (< 0.1 µm) particulate matter (PM) are related to their uptake in macrophages and epithelial cells and their ability to induce oxidative stress. The premise for this study is the increasing awareness that various PM

Ning Li; Constantinos Sioutas; Arthur Cho; Debra Schmitz; Chandan Misra; Joan Sempf; Meiying Wang; Terry Oberley; John Froines; Andre Nel

2002-01-01

468

Calcium sulfate fouling -- Precipitation or particulate: A proposed composite model  

SciTech Connect

Though it is of great importance, the majority of predictive models tend not to incorporate water chemistry in their formulations. The ionic diffusion model which was developed for CaCO{sub 3}, is based purely on crystallization, and is one of the few models that incorporates water chemistry. This model does not provide satisfactory predictions for CaSO{sub 4} fouling. In this article, a new model is proposed for CaSO{sub 4} fouling which takes into account the effect of both crystallization and particulate fouling and is capable of predicting the fouling resistance during the cleaning cycle as well as the fouling cycle. A removal term is incorporated into the model, as the occurrence of particulate fouling for CaSO{sub 4} tends to weaken its crystalline structure and makes it more prone than CaCO{sub 3} to removal. Properties of the electrolyte were evaluated using MINTEQA2 computer code, which is approved by the US Environmental Protection Agency. In this model, particulate fouling is estimated using the physical mechanism for particle transport and adherence, crystallization is estimated by ionic diffusion, and the removal term is approximated using hydrodynamics of flow and deposit properties. The inclusion of both crystallization and removal terms incorporates the effects of both water chemistry and hydrodynamics of the flow and provides a relationship which not only can predict fouling but also can predict dissolution, by change of water quality and/or stopping the operation, or removal by shear stress. The proposed model was assessed using published experimental data. The results indicate that this model provides good prediction. The experimental results, though limited in number, suggest that crystallization is not the main or only mechanism contributing to CaSO{sub 4} fouling. Particulate fouling seems to be a major contributor.

Sheikholeslami, R.

2000-06-01

469

The procoagulant effects of fine particulate matter in vivo  

Microsoft Academic Search

Inhalation of fine particulate matter (<2.5 ?m; fine PM) has been shown to increase the risk for cardiovascular events. In\\u000a this letter, we reappraise the role of tissue factor (TF) antigen and we also summarize changes in measured coagulation proteins\\u000a in humans and rodents by other studies with fine PM. By considering all studies including ours, we conclude that monitoring

Evren Kilinç; Holger Schulz; Gerhardus JAJM Kuiper; Henri MH Spronk; Hugo ten Cate; Swapna Upadhyay; Koustav Ganguly; Tobias Stoeger; Manuela Semmler-Bhenke; Shinji Takenaka; Wolfgang G Kreyling; Mike Pitz; Peter Reitmeir; Annette Peters; Oliver Eickelberg; H Erich Wichmann

2011-01-01

470

Field dependent rf absorption spectra of particulate magnetic recording materials  

NASA Astrophysics Data System (ADS)

Swept frequency absorption (SFA) has been studied in particulate recording materials from 0.2 MHz to 40 GHz and in fields ( B) of up to 2.4 T. Line shapes have been computed as a function of damping parameter ? employing the Landau-Lifshitz equation and Stoner-Wohlfarth model. Experimentally we find ?=?B K ? 0 to be dependent upon particle texture and moment alignment with field B.

Hoon, S. R.; Lawson, G. R.; Thompson, F.; Dean, B.; Chantrell, R. W.

1992-02-01

471

Advanced hybrid particulate collector and method of operation  

DOEpatents

A device and method for controlling particulate air pollutants of the present invention combines filtration and electrostatic collection devices. The invention includes a chamber housing a plurality of rows of filter elements. Between the rows of filter elements are rows of high voltage discharge electrodes. Between the rows of discharge electrodes and the rows of filter elements are grounded perforated plates for creating electrostatic precipitation zones.

Miller, Stanley J. (Grand Forks, ND)

2003-04-08

472

Gaseous and Particulate Iodine in the Marine Atmosphere  

Microsoft Academic Search

Sixty gaseous iodine samples collected from a 20-meter tower on the windward shore of Oahu, Hawaii, during the summer of 1969 showed that the concentration of gaseous iodine ranged from 5 to 20 ng\\/m a. Particulate samples collected simultaneously with the gaseous samples showed that the atmospheric concentrations of gaseous iodine in marine air are 2-4 times the concentration of

Jarvis L. Moyers; Robert A. Duce

1972-01-01

473

Bayesian hierarchical modeling of cardiac response to particulate matter exposure  

Microsoft Academic Search

Studies have linked increased levels of particulate air pollution to decreased autonomic control, as measured by heart rate variability (HRV), particularly in susceptible populations such as the elderly. In this study, we use data obtained from the 1998 USEPA epidemiology-exposure longitudinal panel study of elderly adults in a Baltimore retirement home to examine the relationship between HRV and PM2.5 personal

Sandra J Mcbride; Gary A Norris; Ron W Williams; Lucas M Neas

2011-01-01

474

Stoichiometry of carbon, nitrogen, and phosphorus in marine particulate matter  

Microsoft Academic Search

Abstract--Particulate carbon, nitrogen, and phosphorus were determined in the Atlantic, Indian, and Antarctic oceans and the Mediterranean Sea. Although the regions differ in their hydrology, the slopes of the regression lines between,POC and PON (mean value = 5.6 by atoms) vary <20% in surface waters. The intercept on the POC axis of the POC-PON line is always,positive and represents between,0

Claire Copin-Montegut; Gérard Copin-Montegut

1983-01-01

475

Measurement of fine particulate matter using electron microscopy techniques  

Microsoft Academic Search

Ambient fine particulate matter, defined as material with an aerodynamic diameter less than or equal to 2.5 ?m (PM2.5), comprises a broad range of primary and secondary particles that are dispersed through the atmosphere from a variety of sources. Attention has recently shifted to investigating ambient PM2.5 because fine particles are thought to have a greater influence on health effects.

Gary S Casuccio; Steven F Schlaegle; Traci L Lersch; Gerald P Huffman; Yuanzhi Chen; Naresh Shah

2004-01-01

476

Particulate Carbohydrate and Proteins in the Bay of Bengal  

Microsoft Academic Search

Particulate carbohydrates (PCHO) and proteins (PP) of the offshore waters (depth >200m) were measured within the upper 150m water column along the six transects covering 36 stations perpendicular to the coast in the Bay of Bengal. Concentrations of PCHO and PP ranged from 31 to 158?gl?1and from 0·56 to 2·45?g atomic (at) Nl?1at the surface, and decreased to 7–58?gl?1and 0·43–1·62?g

R. A. Sreepada; C. U. Rivonkar; A. H. Parulekar

1996-01-01

477

Transmittance Enhancement of Packed-Bed Particulate Media  

Microsoft Academic Search

The optical thickness of highly attenuating packed-bed particulate media can be signifi- cantly reduced and, consequently, the radiation heat transfer enhanced, by the addition of large (>100 ?m) semi-transparent SiO2 particles. The monochromatic transmittance of packed-bed mixtures of SiO2, ZnO, and C particles of various relative mass fractions is experimentally measured as a function of the packed-bed thickness using a

W. Lipinski; E. Guillot; G. Olalde; A. Steinfeld

2008-01-01

478

Personal exposure to particulate air pollution in transport microenvironments  

Microsoft Academic Search

Personal measurements of exposure to particulate air pollution (PM10, PM2.5, PM1) were simultaneously made during walking and in-car journeys on two suburban routes in Northampton, UK, during the winter of 1999\\/2000. Comparisons were made between concentrations found in each transport mode by particle fraction, between different particle fractions by transport mode, and between transport microenvironments and a fixed-site monitor located

J. Gulliver; D. J. Briggs

2004-01-01

479

Grooved impactor and inertial trap for sampling inhalable particulate matter  

DOEpatents

An inertial trap and grooved impactor for providing a sharp cutoff for particles over 15 microns from entering an inhalable particulate sampler. The impactor head has a tapered surface and is provided with V-shaped grooves. The tapered surface functions for reducing particle blow-off or reentrainment while the grooves prevent particle bounce. Water droplets and any resuspended material over the 15 micron size are collected by the inertial trap and deposited in a reservoir associated with the impactor.

Loo, Billy W. (Oakland, CA)

1984-01-01

480

Deposition measurement of particulate matter in connection with corrosion studies  

Microsoft Academic Search

A new passive particle collector (inert surrogate surface) that collects particles from all directions has been developed.\\u000a It was used to measure particle deposition at 35 test sites as part of a project that examined corrosion of materials in order\\u000a that variation in particulate material could be used in development of dose–response functions in a modern multi-pollutant\\u000a environment. The project,

Martin Ferm; John Watt; Samantha O’Hanlon; Franco De Santis; Costas Varotsos

2006-01-01

481

MERCURY CONTROL WITH THE ADVANCED HYBRID PARTICULATE COLLECTOR  

SciTech Connect

Since 1995, DOE has supported development of a new concept in particulate control, called the advanced hybrid particulate collector (AHPC). The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas-solid contactor. The objective of the three-task project is to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach includes bench-scale batch testing that ties the new work to previous results and links results with larger-scale pilot testing with real flue gas on a coal-fired combustion system, pilot-scale testing on a coal-fired combustion system with both a pulse-jet baghouse and an AHPC to prove or disprove the research hypotheses, and field demonstration pilot-scale testing at a utility power plant to prove scaleup and demonstrate longer-term mercury control. This project, if successful, will demonstrate at the pilot-scale level a technology that would provide a cost-effective technique to accomplish control of mercury emissions and, at the same time, greatly enhance fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution to a large segment of the U.S. utility industry as well as other industries requiring mercury control.

Ye Zhuang; Stanley J. Miller; Grant E. Dunham; Michelle R. Olderbak

2002-02-01

482

Toward the next generation of air quality monitoring: Particulate Matter  

NASA Astrophysics Data System (ADS)

Fine particulate matter is one of the key global pollutants affecting human health. Satellite and ground-based monitoring technologies as well as chemical transport models have advanced significantly in the past 50 years, enabling improved understanding of the sources of fine particles, their chemical composition, and their effect on human and environmental health. The ability of air pollution to travel across country and geographic boundaries makes particulate matter a global problem. However, the variability in monitoring technologies and programs and poor data availability make global comparison difficult. This paper summarizes fine particle monitoring, models that integrate ground-based and satellite-based data, and communications, then recommends steps for policymakers and scientists to take to expand and improve local and global indicators of particulate matter air pollution. One of the key set of recommendations to improving global indicators is to improve data collection by basing particulate matter monitoring design and stakeholder communications on the individual country, its priorities, and its level of development, while at the same time creating global data standards for inter-country comparisons. When there are good national networks that produce consistent quality data that is shared openly, they serve as the foundation for better global understanding through data analysis, modeling, health impact studies, and communication. Additionally, new technologies and systems should be developed to expand personal air quality monitoring and participation of non-specialists in crowd-sourced data collections. Finally, support to the development and improvement of global multi-pollutant indicators of the health and economic effects of air pollution is essential to addressing improvement of air quality around the world.

Engel-Cox, Jill; Kim Oanh, Nguyen Thi; van Donkelaar, Aaron; Martin, Randall V.; Zell, Erica

2013-12-01

483

Analysis of Particulate Concentrations at Highway Areas in Ulsan  

Microsoft Academic Search

Concentrations of participate matter (PM) on highway areas in Ulsan of Korea were analyzed using a portable PM sampler and a low volume PM10 sampler during a summer sampling period. This study analyzed the air concentrations of PM1.0, PM2.5, PM7.0, PM10, and TSP (total suspended particulate) at 4 places, having quite different environment, located at highway areas in Ulsan. The

Haengah Kim Lee; Byeong-Kyu Lee; Eui-Ryang Jeong; Trang Dong

2006-01-01

484

Fractionator for size classification of aerosolized solid particulate matter  

Microsoft Academic Search

A system is developed for collecting kilogram quantities of size-fractionated particulate matter which can be subsequently used for biologic testing purposes. The apparatus consists of a series of two cyclones and a centripeter and yields four size fractions. When used over a 12-day period to classify fly ash from stack gas passed through the electrostatic precipitator of a coal-fired power

Andrew R. McFarland; Russell W. Bertch; Gerald L. Fisher; Bruce A. Prentice

1977-01-01

485

Development of a Low-Cost Particulate Matter Monitor  

Microsoft Academic Search

We describe a small, inexpensive portable monitor for airborne particulates, composed of the following elements: a. A simple size-selective inlet (vertical elutriator) that permits only particles below a pre-set diameter to pass and enter the measurement section; b. A measurement section in which passing particles are deposited thermophoretically on a micro-fabricated resonant piezoelectric mass sensor; c. An optical characterization module

Richard M. White; Michael G. Apte; Lara A. Gundel; Justin Black

2008-01-01

486

Determination of Levoglucosan in Atmospheric Fine Particulate Matter  

Microsoft Academic Search

A microanalytical method suitable for the quantitative determination of the sugar anhydride levoglucosan in low-volume samples of atmospheric fine particulate matter (PM) has been developed and validated. The method incorporates two sugar anhydrides as quality control standards. The recovery standard sedoheptulosan (2,7-anhydro-?-D-altro-heptulopyranose) in 20 ?L solvent is added onto samples of the atmospheric fine PM and aged for 1 hr

Christopher D. Simpson; Russell L. Dills; Bethany S. Katz; David A. Kalman

2004-01-01

487

Stochastic modeling of fine particulate organic carbon dynamics in rivers  

NASA Astrophysics Data System (ADS)

majority of particulate organic matter standing stock in streams is < 1 mm in diameter, and the mobile phase is primarily very fine particles. Such fine particles transport downstream in a series of deposition and resuspension events mediated by interactions with coarser bed sediment, yielding fine particle retention over a wide range of time scales. This retention controls the opportunity for biogeochemical processing of particulate organic carbon in streams. We present a conceptual model of particulate organic carbon transport in rivers categorized in three cyclic processes: (i) migration of fine particles from the water column to the underlying and surrounding sediments, (ii) fine particle transport and retention within the bed sediments, and (iii) resuspension of fine particles back to the water column. We developed a stochastic model to describe the transport and retention of fine suspended particles in rivers, including advective delivery of particles to the streambed, transport through pore waters, and reversible filtration within the streambed. We then apply this model to observations of fine particle transport in two small streams, and show that the stochastic mobile-immobile model supports improved interpretation of particulate organic carbon dynamics under base flow conditions. Analysis of in-stream solute and particle data shows that particles engage in multiple deposition and resuspension events during downstream transport, and that long-term retention in the streambed produces extended slow releases to the stream even during base flow conditions. We also show how multiscale stochastic modeling can be used to incorporate local observations of particle retention in predictions of whole-stream particle dynamics.

Drummond, J. D.; Aubeneau, A. F.; Packman, A. I.

2014-05-01

488

Chemical Characterization of Particulate Matter Emitted from Animal Feeding Operations  

Microsoft Academic Search

This paper reports a field study of concentration and chemical characterization of PM2.5 emitted from a large egg production facility. PM2.5 samples were taken at five sampling locations covering emission source (in a layer barn) and four ambient stations at four wind directions surrounding the facility. Eight particulate matter (PM) sampling events were conducted from December 2008 to February 2009,

Qianfeng Li; Lingjuan Wang; Zifei Liu; David B. Beasley

489

Dryout heat fluxes for inductively heated particulate beds  

Microsoft Academic Search

Experimental observations of the dryout heat fluxes for inductively heated particulate beds have been made. The data were obtained when steel and lead particles in the size distribution 295 to 787 microns were placed in a 4.7-cm dia pyrex glass jar and inductively heated by passing radio frequency current through a 13.3-cm dia multiturn work coil encircling the jar. Distilled

V. Dhir; I. Catton

1977-01-01

490

Model uncertainty and health effect studies for particulate matter  

Microsoft Academic Search

this articlehas been funded in part by the United States Environmental Protection Agency throughagreement CR825173-01-0 to the University of Washington, it has as not been subjected tothe Agency's required peer and policy review and therefore does not necessarily reflect theviews of the Agency and no official endorsement should be inferred.Model Uncertainty andHealth Effect Studies for Particulate MatterSummary

Merlise Clyde

2000-01-01

491

The effect of particulate air pollution on life expectancy  

Microsoft Academic Search

Two recent US cohort studies suggest that current levels of particulate pollution in urban air are associated not only with short-term, but also with long-term increases in cardiorespiratory morbidity and mortality. The aim of the present analyses was to evaluate the change in life expectancy assuming the long-term increase in mortality rates as suggested by these studies. The method of

Jaakko Nevalainen; Juha Pekkanen

1998-01-01

492

Photoelectrochemistry of semiconductor ZnO particulate films  

Microsoft Academic Search

This paper reports on thin films of ZnO semiconductor that have been prepared on electrode surfaces by coating them with quantized ZnO colloids. The photoelectrochemical properties of semiconductor particulate films have been evaluated with both steady-state and laser pulse excitations. The ZnO film behaves like an n-type semiconductor with a flatband potential of -0.6 V vs. SCE. The incident-photon conversion

Surat Hotchandani; P. V. Kamat

1992-01-01

493

CURRENT ISSUES ON DRYING OF PARTICULATE MATERIALS - A CANADIAN PROSPECTIVE  

Microsoft Academic Search

This paper provides an industrially oriented review of selected drying technologies for particulate materials that have been developed in Canada over a past decade. These are: the pulsed fluid bed dryer, rotating jet spouted bed dryer, ambient air-temperature dryer, pulsed combustion flash dryer, Helix dryer and ring-to-ring dryer. In view of a growing interest in osmotic dehydration as a pre-treatment

Tadeusz Kudra

494

Therapeutic potentials of ecto-nucleoside triphosphate diphosphohydrolase, ecto-nucleotide pyrophosphatase/phosphodiesterase, ecto-5'-nucleotidase, and alkaline phosphatase inhibitors.  

PubMed

The modulatory role of extracellular nucleotides and adenosine in relevance to purinergic cell signaling mechanisms has long been known and is an object of much research worldwide. These extracellular nucleotides are released by a variety of cell types either innately or as a response to patho-physiological stress or injury. A variety of surface-located ecto-nucleotidases (of four major types; nucleoside triphosphate diphosphohydrolases or NTPDases, nucleotide pyrophosphatase/phosphodiesterases or NPPs, alkaline phosphatases APs or ALPs, and ecto-5'-nucleotidase or e5NT) are responsible for meticulously controlling the availability of these important signaling molecules (at their respective receptors) in extracellular environment and are therefore crucial for maintaining the integrity of normal cell functioning. Overexpression of many of these ubiquitous ecto-enzymes has been implicated in a variety of disorders including cell adhesion, activation, proliferation, apoptosis, and degenerative neurological and immunological responses. Selective inhibition of these ecto-enzymes is an area that is currently being explored with great interest and hopes remain high that development of selective ecto-nucleotidase inhibitors will prove to have many beneficial therapeutic implications. The aim of this review is to emphasize and focus on recent developments made in the field of inhibitors of ecto-nucleotidases and to highlight their structure activity relationships wherever possible. Most recent and significant advances in field of NTPDase, NPP, AP, and e5NT inhibitors is being discussed in detail in anticipation of providing prolific leads and relevant background for research groups interested in synthesis of selective ecto-nucleotidase inhibitors. PMID:24115166

Al-Rashida, Mariya; Iqbal, Jamshed

2014-07-01

495

Acute Caffeine Treatment Increases Extracellular Nucleotide Hydrolysis from Rat Striatal and Hippocampal Synaptosomes  

Microsoft Academic Search

The psychostimulant caffeine promotes behavioral effects such as hyperlocomotion, anxiety, and disruption of sleep by blockade of adenosine receptors. The availability of extracellular adenosine depends on its release by transporters or by the extracellular ATP catabolism performed by the ecto-nucleotidase pathway. This study verified the effect of caffeine on NTP-Dase 1 (ATP diphosphohydrolase) and 5'-nucleotidase of synaptosomes from hippocampus and

Rosane Souza da Silva; Alessandra Nejar Bruno; Ana Maria Oliveira Battastini; João José Freitas Sarkis; Diogo Rizzato Lara; Carla Denise Bonan

2003-01-01

496

Physiological roles for ecto-5’-nucleotidase (CD73)  

Microsoft Academic Search

Nucleotides and nucleosides influence nearly every aspect of physiology and pathophysiology. Extracellular nucleotides are\\u000a metabolized through regulated phosphohydrolysis by a series of ecto-nucleotidases. The formation of extracellular adenosine\\u000a from adenosine 5’-monophosphate is accomplished primarily through ecto-5’-nucleotidase (CD73), a glycosyl phosphatidylinositol-linked\\u000a membrane protein found on the surface of a variety of cell types. Recent in vivo studies implicating CD73 in a

Sean P. Colgan; Holger K. Eltzschig; Tobias Eckle; Linda F. Thompson

2006-01-01

497

Blockade of murine T cell activation by antagonists of P2Y 6 and P2X 7 receptors  

Microsoft Academic Search

Extracellular nucleotides and their metabolites activate ionotropic P2X and metabotropic P2Y receptors on the surface of various types of cells. Here, we investigated the involvement of P2X and P2Y receptor-mediated signaling in TCR-dependent T cell activation. Murine T cells were activated by stimulation of TCR, and both CD25 expression and interleukin (IL)-2 production were observed in activated T cells. Ecto-nucleotidase

Mitsutoshi Tsukimoto; Akihiro Tokunaga; Hitoshi Harada; Shuji Kojima

2009-01-01

498

Purinergic P2Y6 Receptors Induce Ca2+ and CFTR Dependent Cl Secretion in Mouse Trachea  

Microsoft Academic Search

In airways Cl- secretion is activated and Na+ absorption is inhibited when P2Y2 receptors are stimulated by ATP or UTP. Both nucleotides are subject to degradation to ADP and UDP by ecto-nucleotidases. Here we show that these metabolites change electrolyte transport by stimulation of P2Y6 receptors in mouse trachea. Immunohistochemistry confirmed luminal and basolateral expression of P2Y 6 receptors. In

Rainer Schreiber; Karl Kunzelmann

2005-01-01

499

Modelisation des emissions de particules microniques et nanometriques en usinage  

NASA Astrophysics Data System (ADS)

La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

Khettabi, Riad

500

Performance comparison of three samplers of suspended airborne particulate matter  

SciTech Connect

The University of Arizona and the Pima County Air Pollution Control District conducted a comparison study of the following aerosol samplers: a standard high-volume sampler, a high-volume sampler fitted with a size selective inlet, and a dichotomous virtua