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Sample records for accelerated-senescence oxys rats

  1. Antiaging Effect of Metformin on Brain in Naturally Aged and Accelerated Senescence Model of Rat.

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    Garg, Geetika; Singh, Sandeep; Singh, Abhishek Kumar; Rizvi, Syed Ibrahim

    2017-01-09

    Metformin, a biguanide, is a widely used antidiabetic drug, which inhibits gluconeogenesis and is used to treat hyperglycemia in type 2 diabetes. Through activation of AMPK (AMP-activated protein kinase) pathway, metformin also mimics caloric restriction health benefits. Aging causes substantial molecular to morphological changes in brain, the brain cells being more susceptible toward oxidative stress mediated damages due to the presence of high lipid content and higher oxygen consumption. Wistar rats (naturally aged and d-galactose induced rat model) were supplemented with metformin (300 mg/kg b.w. orally) for 6 weeks. The biomarkers of oxidative stress such as antioxidant capacity (ferric reducing antioxidant potential [FRAP]), malondialdehyde (MDA), reduced glutathione (GSH), protein carbonyl (PCO), reactive oxygen species (ROS), acetylcholinesterase (AChE) activity, and nitric oxide (NO) were measured in brain tissues of control and experimental groups. The results indicate that metformin treatment augmented the levels of FRAP and GSH in naturally aged, and d-gal induced aging model groups compared to the respective controls. In contrast, metformin treated groups exhibited significant reduction in MDA, PCO, ROS, and NO levels and a significant increase in AChE activity in induced aging rats. The administration of d-galactose upregulated the expression of sirtuin-2, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) and downregulated the expression of Beclin-1. Metformin supplementation downregulated the d-galactose induced expressions of sirtuin-2, IL-6, and TNF-α expression, whereas upregulated the Beclin-1 expression. Our data confirm that metformin restores the antioxidant status and improves healthy brain aging through the activation of autophagy and reduction in inflammation.

  2. Rapamycin suppresses brain aging in senescence-accelerated OXYS rats.

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    Kolosova, Nataliya G; Vitovtov, Anton O; Muraleva, Natalia A; Akulov, Andrey E; Stefanova, Natalia A; Blagosklonny, Mikhail V

    2013-06-01

    Cellular and organismal aging are driven in part by the MTOR (mechanistic target of rapamycin) pathway and rapamycin extends life span inC elegans, Drosophila and mice. Herein, we investigated effects of rapamycin on brain aging in OXYS rats. Previously we found, in OXYS rats, an early development of age-associated pathological phenotypes similar to several geriatric disorders in humans, including cerebral dysfunctions. Behavioral alterations as well as learning and memory deficits develop by 3 months. Here we show that rapamycin treatment (0.1 or 0.5 mg/kg as a food mixture daily from the age of 1.5 to 3.5 months) decreased anxiety and improved locomotor and exploratory behavior in OXYS rats. In untreated OXYS rats, MRI revealed an increase of the area of hippocampus, substantial hydrocephalus and 2-fold increased area of the lateral ventricles. Rapamycin treatment prevented these abnormalities, erasing the difference between OXYS and Wister rats (used as control). All untreated OXYS rats showed signs of neurodegeneration, manifested by loci of demyelination. Rapamycin decreased the percentage of animals with demyelination and the number of loci. Levels of Tau and phospho-Tau (T181) were increased in OXYS rats (compared with Wistar). Rapamycin significantly decreased Tau and inhibited its phosphorylation in the hippocampus of OXYS and Wistar rats. Importantly, rapamycin treatment caused a compensatory increase in levels of S6 and correspondingly levels of phospo-S6 in the frontal cortex, indicating that some downstream events were compensatory preserved, explaining the lack of toxicity. We conclude that rapamycin in low chronic doses can suppress brain aging.

  3. Analysis of mitochondrial DNA somatic mutations in OXYS and Wistar strain rats.

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    Rotskaya, U N; Rogozin, I B; Vasyunina, E A; Kolosova, N G; Malyarchuk, B A; Nevinsky, G A; Sinitsyna, O I

    2009-04-01

    Rats of the OXYS strain are sensitive to oxidative stress and serve as a biological model of premature aging. We have compared spectra of somatic mutations in a control region of mtDNA from the liver of the OXYS rat strain and of Wistar rats as a control. The majority of nucleotide substitutions in the mutation spectra were represented by transitions: 94 and 97% in the OXYS and Wistar rats, respectively. It was shown that 40% of somatic mutations in the control region of mtDNA from Wistar rats were significantly consistent with the model of dislocation mutagenesis. No statistical support for this model was found for mutations in the control region of mtDNA from OXYS rats. The mutation frequency in the ETAS section was higher in the OXYS strain rats than in Wistar rats. These results suggest different mechanisms of mutagenesis in the two rat strains under study.

  4. The Mitochondria-Targeted Antioxidant SkQ1 Downregulates Aryl Hydrocarbon Receptor-Dependent Genes in the Retina of OXYS Rats with AMD-Like Retinopathy

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    M. L. Perepechaeva

    2014-01-01

    Full Text Available The mitochondria-targeted antioxidant SkQ1 is a novel drug thought to retard development of age-related diseases. It has been shown that SkQ1 reduces clinical signs of retinopathy in senescence-accelerated OXYS rats, which are a known animal model of human age-related macular degeneration (AMD. The aim of this work was to test whether SkQ1 affects transcriptional activity of AhR (aryl hydrocarbon receptor and Nrf2 (nuclear factor erythroid 2-related factor 2, which are considered as AMD-associated genes in the retina of OXYS and Wistar rats. Our results showed that only AhR and AhR-dependent genes were sensitive to SkQ1. Dietary supplementation with SkQ1 decreased the AhR mRNA level in both OXYS and Wistar rats. At baseline, the retinal Cyp1a1 mRNA level was lower in OXYS rats. SkQ1 supplementation decreased the Cyp1a1 mRNA level in Wistar rats, but this level remained unchanged in OXYS rats. Baseline Cyp1a2 and Cyp1b1 mRNA expression was stronger in OXYS than in Wistar rats. In the OXYS strain, Cyp1a2 and Cyp1b1 mRNA levels decreased as a result of SkQ1 supplementation. These data suggest that the Cyp1a2 and Cyp1b1 enzymes are involved in the pathogenesis of AMD-like retinopathy of OXYS rats and are possible therapeutic targets of SkQ1.

  5. Telomerase prevents accelerated senescence in glucose-6-phosphate dehydrogenase (G6PD-deficient human fibroblasts

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    Wu Yi-Hsuan

    2009-02-01

    Full Text Available Abstract Fibroblasts derived from glucose-6-phosphate dehydrogenase (G6PD-deficient patients display retarded growth and accelerated cellular senescence that is attributable to increased accumulation of oxidative DNA damage and increased sensitivity to oxidant-induced senescence, but not to accelerated telomere attrition. Here, we show that ectopic expression of hTERT stimulates telomerase activity and prevents accelerated senescence in G6PD-deficient cells. Stable clones derived from hTERT-expressing normal and G6PD-deficient fibroblasts have normal karyotypes, and display no sign of senescence beyond 145 and 105 passages, respectively. Activation of telomerase, however, does not prevent telomere attrition in earlier-passage cells, but does stabilize telomere lengths at later passages. In addition, we provide evidence that ectopic expression of hTERT attenuates the increased sensitivity of G6PD-deficient fibroblasts to oxidant-induced senescence. These results suggest that ectopic expression of hTERT, in addition to acting in telomere length maintenance by activating telomerase, also functions in regulating senescence induction.

  6. Effects of the Oxygen-Carrying Solution OxyVita C on the Cerebral Microcirculation and Systemic Blood Pressures in Healthy Rats

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    Rania Abutarboush

    2014-11-01

    Full Text Available The use of hemoglobin-based oxygen carriers (HBOC as oxygen delivering therapies during hypoxic states has been hindered by vasoconstrictive side effects caused by depletion of nitric oxide (NO. OxyVita C is a promising oxygen-carrying solution that consists of a zero-linked hemoglobin polymer with a high molecular weight (~17 MDa. The large molecular weight is believed to prevent extravasation and limit NO scavenging and vasoconstriction. The aim of this study was to assess vasoactive effects of OxyVita C on systemic blood pressures and cerebral pial arteriole diameters. Anesthetized healthy rats received four intravenous (IV infusions of an increasing dose of OxyVita C (2, 25, 50, 100 mg/kg and hemodynamic parameters and pial arteriolar diameters were measured pre- and post-infusion. Normal saline was used as a volume-matched control. Systemic blood pressures increased (P ≤ 0.05 with increasing doses of OxyVita C, but not with saline. There was no vasoconstriction in small (<50 µm and medium-sized (50–100 µm pial arterioles in the OxyVita C group. In contrast, small and medium-sized pial arterioles vasoconstricted in the control group. Compared to saline, OxyVita C showed no cerebral vasoconstriction after any of the four doses evaluated in this rat model despite increases in blood pressure.

  7. Carbamylated low-density lipoprotein induces oxidative stress and accelerated senescence in human endothelial progenitor cells.

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    Carracedo, Julia; Merino, Ana; Briceño, Carolina; Soriano, Sagrario; Buendía, Paula; Calleros, Laura; Rodriguez, Mariano; Martín-Malo, Alejandro; Aljama, Pedro; Ramírez, Rafael

    2011-04-01

    Carbamylated low-density lipoprotein (cLDL) plays a role in atherosclerosis. In this study we evaluate the effect of uremia on LDL carbamylation and the effect of cLDL and oxidized LDL (oxLDL; 200 μg/ml) on number, function, and genomic stability of endothelial progenitor cells (EPCs) obtained from healthy volunteers. cLDL was generated after incubation of native LDL (nLDL) with uremic serum from patients with chronic kidney disease (CKD) stages 2-4. Oxidative stress was measured by flow cytometry and fluorescent microscopy, mitochondrial depolarization by flow cytometry, senescence by β-galactosidase activity and telomere length, and DNA damage by phosphorylated histone H2AX (γH2AX). The percentage of cLDL by uremic serum was related to the severity of CKD. Compared with nLDL, cLDL induced an increase in oxidative stress (62±5 vs. 8±3%, P<0.001) and cells with mitochondrial depolarization (73±7 vs. 9±5%, P<0.001), and a decrease in EPC proliferation and angiogenesis. cLDL also induced accelerated senescence (73±16 vs. 12±9%, P<0.001), which was associated with a decrease in the expression of γH2AX (62±9 vs. 5±3%, P<0.001). The degree of injury induced by cLDL was comparable to that observed with oxLDL. This study supports the hypothesis that cLDL triggers genomic damage in EPCs, resulting in premature senescence. We can, therefore, hypothesize that EPCs injury by cLDL contributes to an increase in atherosclerotic disease in CKD.

  8. Therapeutic action of the mitochondria-targeted antioxidant SkQ1 on retinopathy in OXYS rats linked with improvement of VEGF and PEDF gene expression.

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    Anton M Markovets

    Full Text Available UNLABELLED: The incidence of age-related macular degeneration (AMD, the main cause of blindness in older patients in the developed countries, is increasing with the ageing population. At present there is no effective treatment for the prevailing geographic atrophy, dry AMD, whereas antiangiogenic therapies successful used in managing the wet form of AMD. Recently we showed that mitochondria-targeted antioxidant plastoquinonyl-decyl-triphenylphosphonium (SkQ1 is able to prevent the development and moreover caused regression of pre-existing signs of the retinopathy in OXYS rats, an animal model of AMD. Here we examine the effects of SkQ1 on expression of key regulators of angiogenesis vascular endothelial growth factor A (VEGF and its antagonist pigment epithelium-derived factor (PEDF genes in the retina of OXYS rats as evidenced by real-time PCR and an ELISA test for VEGF using Wistar rats as control. Ophthalmoscopic examinations confirmed that SkQ1 supplementation (from 1.5 to 3 months of age, 250 nmol/kg prevented development while eye drops SkQ1 (250 nM, from 9 to 12 months caused some reduction of retinopathy signs in OXYS rats and did not reveal any negative effects on the control Wistar rat's retina. Prevention of premature retinopathy by SkQ1 was connected with an increase of VEGF mRNA and protein in OXYS rat's retina up to the levels corresponding to the Wistar rats, and did not involve changes in PEDF expression. In contrast the treatment with SkQ1 drops caused a decrease of VEGF mRNA and protein levels and an increase in the PEDF mRNA level in the middle-aged OXYS rats, but in Wistar rats the changes of gene expression were the opposite. CONCLUSIONS: The beneficial effects of SkQ1 on retinopathy connected with normalization of expression of VEGF and PEDF in the retina of OXYS rats and depended on age of the animals and the stage of retinopathy.

  9. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

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    Azad, Arun, E-mail: arun.azad@bccancer.bc.ca [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Pathology, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Bukczynska, Patricia; Jackson, Susan [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Haput, Ygal; Cullinane, Carleen [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia); McArthur, Grant A.; Solomon, Benjamin [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Division of Cancer Medicine, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Medicine, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia)

    2014-02-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination.

  10. Alpha fucosidase and beta galactosidase in serum of a Lyme disease patients as a possible marker of accelerated senescence — a preliminary study

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    Anna Wasiluk

    2012-07-01

    Full Text Available Lyme disease (LD is the most prevalent tick-borne disease in Europe. LD is caused by the spirochete Borrelia burgdorferi. LD is a chronic disease which can attack a number of organs: skin, heart, brain, joints. Chronic, low-grade inflammation involves general production of pro-inflammatory cytokines and inflammatory markers and is a typical feature of aging. So far, the best method of diagnosing LD is a time-consuming and expensive two-stage serological method. The aim of our study was to evaluate the activity of two lysosomal exoglycosidases: α-fucosidase (FUC and β-galactosidase (GAL in the serum of patients with Lyme disease, as potential markers of LD. Due to the increasing number of patients with Lyme disease and a number of false results, new ways to diagnose this disease are still being sought. As elevated level of β-galactosidase is a manifestation of residual lysosomal activity in senescent cells, the increase in its activity in serum during chronic Lyme disease might be a marker of a potentially accelerated senescence process. The study was performed on serum taken from cubital veins of 15 patients with Lyme disease and eight healthy subjects (control group. FUC and GAL activity was measured by the method of Chatterjee et al. as modified by Zwierz et al. In the serum of patients with Lyme disease, GAL activity significantly increased (p = 0.029, and the activity of FUC had a tendency to increase (p = 0.153, compared to the control group. A significant increase in GAL activity in the serum of patients with Lyme disease indicates an increased catabolism of glycoconjugates (glycoproteins, glycolipids, proteoglycans and could be helpful in the diagnosis of Lyme disease, although this requires confirmation in a larger group of patients. As GAL is the most widely used assay for detection of senescent cells, an elevated level of β-galactosidase might be a manifestation of accelerated senescence process in the course of Lyme

  11. Synthetic Resveratrol Analogue, 3,3',4,4',5,5'-Hexahydroxy-trans-Stilbene, Accelerates Senescence in Peritoneal Mesothelium and Promotes Senescence-Dependent Growth of Gastrointestinal Cancers

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    Krzysztof Książek

    2013-11-01

    Full Text Available 3,3',4,4',5,5'-Hexahydroxy-trans-stilbene (M8 is a synthetic resveratrol derivative, advertised as a candidate drug highly effective against numerous malignancies. Because multiple tumors prone to M8 frequently metastasize into the peritoneal cavity, this study was aimed at establishing the effect of M8 on the growth and senescence of human peritoneal mesothelial cells (HPMCs, the largest cell population within the peritoneum, actively involved in the intraperitoneal spread of cancer. The study showed that M8, used at the highest non-toxic dose of 10 μM, impairs proliferation and accelerates senescence in cultured HPMCs via an oxidative stress-dependent mechanism. At the same time, soluble factors released to the environment by HPMCs that senesced prematurely in response to M8 promoted growth of colorectal and pancreatic carcinomas in vitro. These findings indicate that M8 may indirectly—through the modification of normal (mesothelial cells phenotype—facilitate an expansion of cancer cells, which challenges the postulated value of this stilbene in chemotherapy.

  12. Western diet consumption promotes vascular remodeling in non-senescent mice consistent with accelerated senescence, but does not modify vascular morphology in senescent ones.

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    Dantas, Ana Paula; Onetti, Yara; Oliveira, María Aparecida; Carvalho, Maria Helena; Heras, Magda; Vila, Elisabet; Jiménez-Altayó, Francesc

    2014-07-01

    Senescence accelerated mice (SAM) are susceptible to developing vascular dysfunction and remodeling. Food intake and type of diet have also been identified as determining factors in vascular remodeling. However, the interplay between senescence and diet in vascular remodeling is largely unknown. We aimed to analyze structure of large (aorta) and small (mesenteric; MA) arteries from seven-month-old SAM prone (SAMP8) and resistant (SAMR1) mice that received a Western-type high-fat diet (WD; 8weeks). Aortic structure was assessed by morphometric analysis of hematoxylin and eosin-stained cross sections, and collagen content by qRT-PCR, immunofluorescence and picrosirius red. In MAs, structural and mechanical properties were measured by pressure myography; elastin and collagen content by qRT-PCR and immunofluorescence; nuclei distribution by confocal microscopy; and apoptosis by qRT-PCR and TUNEL assay. In aorta, wall thickness (WT), but not cross-sectional area (CSA), was increased by senescence, and WD only increased WT in SAMR1. WD intake, but not senescence, was associated with increased collagen deposition. In MAs, senescence diminished WT and CSA, without altering collagen and elastin deposition, reduced the number of MA wall cells, and increased pro apoptotic activation. WD consumption promoted in SAMR1 the same remodeling observed with senescence, while in SAMP8 the senescence-associated changes remained unaffected. The mechanisms involved in WD-induced MA remodeling in SAMR1 mimicked those observed in senescence per se. Our study reveals qualitatively different remodeling in aortas and MAs from senescent mice. Consumption of a WD induced remodeling of the SAMR1 vasculature similar to that induced by senescence, while it did not promote any further alteration in the latter. Therefore, we propose that increased consumption of fat-enriched diets could promote accelerated senescence of the non-senescent vasculature, although it does not exacerbate vascular

  13. Haemophilus influenzae OxyR: characterization of its regulation, regulon and role in fitness.

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    Paul W Whitby

    Full Text Available To prevent damage by reactive oxygen species, many bacteria have evolved rapid detection and response systems, including the OxyR regulon. The OxyR system detects reactive oxygen and coordinates the expression of numerous defensive antioxidants. In many bacterial species the coordinated OxyR-regulated response is crucial for in vivo survival. Regulation of the OxyR regulon of Haemophilus influenzae was examined in vitro, and significant variation in the regulated genes of the OxyR regulon among strains of H. influenzae was observed. Quantitative PCR studies demonstrated a role for the OxyR-regulated peroxiredoxin/glutaredoxin as a mediator of the OxyR response, and also indicated OxyR self-regulation through a negative feedback loop. Analysis of transcript levels in H. influenzae samples derived from an animal model of otitis media demonstrated that the members of the OxyR regulon were actively upregulated within the chinchilla middle ear. H. influenzae mutants lacking the oxyR gene exhibited increased sensitivity to challenge with various peroxides. The impact of mutations in oxyR was assessed in various animal models of H. influenzae disease. In paired comparisons with the corresponding wild-type strains, the oxyR mutants were unaffected in both the chinchilla model of otitis media and an infant model of bacteremia. However, in weanling rats the oxyR mutant was significantly impaired compared to the wild-type strain. In contrast, in all three animal models when infected with a mixture of equal numbers of both wild-type and mutant strains the mutant strain was significantly out competed by the wild-type strain. These findings clearly establish a crucial role for OxyR in bacterial fitness.

  14. Haemophilus influenzae OxyR: Characterization of Its Regulation, Regulon and Role in Fitness

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    Whitby, Paul W.; Morton, Daniel J.; VanWagoner, Timothy M.; Seale, Thomas W.; Cole, Brett K.; Mussa, Huda J.; McGhee, Phillip A.; Bauer, Chee Yoon S.; Springer, Jennifer M.; Stull, Terrence L.

    2012-01-01

    To prevent damage by reactive oxygen species, many bacteria have evolved rapid detection and response systems, including the OxyR regulon. The OxyR system detects reactive oxygen and coordinates the expression of numerous defensive antioxidants. In many bacterial species the coordinated OxyR-regulated response is crucial for in vivo survival. Regulation of the OxyR regulon of Haemophilus influenzae was examined in vitro, and significant variation in the regulated genes of the OxyR regulon among strains of H. influenzae was observed. Quantitative PCR studies demonstrated a role for the OxyR-regulated peroxiredoxin/glutaredoxin as a mediator of the OxyR response, and also indicated OxyR self-regulation through a negative feedback loop. Analysis of transcript levels in H. influenzae samples derived from an animal model of otitis media demonstrated that the members of the OxyR regulon were actively upregulated within the chinchilla middle ear. H. influenzae mutants lacking the oxyR gene exhibited increased sensitivity to challenge with various peroxides. The impact of mutations in oxyR was assessed in various animal models of H. influenzae disease. In paired comparisons with the corresponding wild-type strains, the oxyR mutants were unaffected in both the chinchilla model of otitis media and an infant model of bacteremia. However, in weanling rats the oxyR mutant was significantly impaired compared to the wild-type strain. In contrast, in all three animal models when infected with a mixture of equal numbers of both wild-type and mutant strains the mutant strain was significantly out competed by the wild-type strain. These findings clearly establish a crucial role for OxyR in bacterial fitness. PMID:23226321

  15. Oxy-coal Combustion Studies

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    Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)

    2012-01-06

    The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

  16. Oxy Coal Combustion at the US EPA

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    Oxygen enriched coal (oxy-coal) combustion is a developing, and potentially a strategically key technology intended to accommodate direct CO2 recovery and sequestration. Oxy-coal combustion is also intended for retrofit application to existing power plants. During oxy-coal comb...

  17. Oxy-fuel combustion of solid fuels

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg; Brix, Jacob; Jensen, Peter Arendt

    2010-01-01

    Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO2 from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame...... temperature. The flue gas produced thus consists primarily of carbon dioxide and water. Much research on the different aspects of an oxy-fuel power plant has been performed during the last decade. Focus has mainly been on retrofits of existing pulverized-coal-fired power plant units. Green-field plants which...... provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy-fuel...

  18. Oxy-Combustion Boiler Material Development

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    Michael Gagliano; Andrew Seltzer; Hans Agarwal; Archie Robertson; Lun Wang

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO{sub 2} level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to

  19. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

    Gagliano, Michael; Seltzer, Andrew; Agarwal, Hans; Robertson, Archie; Wang, Lun

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO2 level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to two year

  20. Modeling of large-scale oxy-fuel combustion processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    Quite some studies have been conducted in order to implement oxy-fuel combustion with flue gas recycle in conventional utility boilers as an effective effort of carbon capture and storage. However, combustion under oxy-fuel conditions is significantly different from conventional air-fuel firing......, among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a 609MW utility boiler is numerically studied, in which...... calculation of the oxy-fuel WSGGM remarkably over-predicts the radiative heat transfer to the furnace walls and under-predicts the gas temperature at the furnace exit plane, which also result in a higher incomplete combustion in the gray calculation. Moreover, the gray and non-gray calculations of the same...

  1. 4-Meth-oxy-3-(meth-oxy-meth-yl)benzalde-hyde.

    Science.gov (United States)

    Zhang, Jing-Chao; Sun, Jun; Zhang, Juan; Liu, Guang-Lin; Guo, Cheng

    2013-01-01

    In the title compound, C10H12O3, the dihedral angle between the benzene ring and the meth-oxy-methyl side chain is 9.7 (2)°. The O atom of the aldehyde group and the C atom of the meth-oxy group deviate from the plane of the ring by 0.039 (3) and 0.338 (4) Å, respectively. The only inter-molecular inter-actions are very weak C-H⋯π inter-actions.

  2. Advanced modeling of oxy-fuel combustion of natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Chungen Yin

    2011-01-15

    The main goal of this small-scale project is to investigate oxy-combustion of natural gas (NG) through advanced modeling, in which radiation, chemistry and mixing will be reasonably resolved. 1) A state-of-the-art review was given regarding the latest R and D achievements and status of oxy-fuel technology. The modeling and simulation status and achievements in the field of oxy-fuel combustion were also summarized; 2) A computer code in standard c++, using the exponential wide band model (EWBM) to evaluate the emissivity and absorptivity of any gas mixture at any condition, was developed and validated in detail against data in literature. A new, complete, and accurate WSGGM, applicable to both air-fuel and oxy-fuel combustion modeling and applicable to both gray and non-gray calculation, was successfully derived, by using the validated EWBM code as the reference mode. The new WSGGM was implemented in CFD modeling of two different oxy-fuel furnaces, through which its great, unique advantages over the currently most widely used WSGGM were demonstrated. 3) Chemical equilibrium calculations were performed for oxy-NG flame and air-NG flame, in which dissociation effects were considered to different degrees. Remarkable differences in oxy-fuel and air-fuel combustion were revealed, and main intermediate species that play key roles in oxy-fuel flames were identified. Different combustion mechanisms are compared, e.g., the most widely used 2-step global mechanism, refined 4-step global mechanism, a global mechanism developed for oxy-fuel using detailed chemical kinetic modeling (CHEMKIN) as reference. 4) Over 15 CFD simulations were done for oxy-NG combustion, in which radiation, chemistry, mixing, turbulence-chemistry interactions, and so on were thoroughly investigated. Among all the simulations, RANS combined with 2-step and refined 4-step mechanism, RANS combined with CHEMKIN-based new global mechanism for oxy-fuel modeling, and LES combined with different combustion

  3. Control issues in oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Snarheim, Dagfinn

    2009-08-15

    Combustion of fossil fuels is the major energy source in todays society. While the use of fossil fuels is a necessity for our society to function, there has been an increasing concern on the emissions of CO{sub 2} resulting from human activities. Emissions of CO{sub 2} are considered to be the main cause for the global warming and climate changes we have experienced in recent years. To fight the climate changes, the emissions of CO{sub 2} must be reduced in a timely fashion. Strategies to achieve this include switching to less carbon intensive fuels, renewable energy sources, nuclear energy and combustion with CO{sub 2} capture. The use of oxy-fuel combustion is among the alternative post- and pre combustion capture concepts, a strategy to achieve power production from fossil fuels with CO{sub 2} capture. In an oxy-fuel process, the fuel is burned in a mixture of oxygen and CO{sub 2} (or steam), leaving the exhaust consisting mainly of CO{sub 2} and steam. The steam can be removed by use of a condenser, leaving (almost) pure CO{sub 2} ready to be captured. The downside to CO{sub 2} capture is that it is expensive, both in capital cost of extra equipment, and in operation as it costs energy to capture the CO{sub 2}. Thus it is important to maximize the efficiency in such plants. One attractive concept to achieve CO{sub 2} capture by use of oxy-fuel, is a semi-closed oxy-fuel gas turbine cycle. The dynamics of such a plant are highly integrated, involving energy and mass recycle, and optimizing efficiency might lead to operational (control) challenges. In these thesis we investigate how such a power cycle should be controlled. By looking at control at such an early stage in the design phase, it is possible to find control solutions otherwise not feasible, that leads to better overall performance. Optimization is used on a nonlinear model based on first principles, to compare different control structures. Then, closed loop simulations using MPC, are used to validate

  4. Oxy-combustor operable with supercritical fluid

    Energy Technology Data Exchange (ETDEWEB)

    Brun, Klaus; McClung, Aaron M.; Owston, Rebecca A.

    2017-04-04

    An oxy-combustor is provided which comprises a combustion vessel including at least one solid fuel slurry inlet port, at least one oxygen inlet port and at least one supercritical fluid inlet port, wherein the combustion vessel is operable at an operating pressure of at least 1,100 psi; an interior of the combustion vessel comprises a combustion chamber and a supercritical fluid infusion chamber surrounding at least a part of the combustion chamber, the supercritical fluid infusion chamber and the combustion chamber are separated by a porous liner surrounding the combustion chamber, and the supercritical infusion chamber is located between the porous liner and an outer casing of the combustion vessel.

  5. Chemistry and radiation in oxy-fuel combustion

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse; Kær, Søren Knudsen

    2011-01-01

    In order to investigate the role of combustion chemistry and radiation heat transfer in oxy-fuel combustion modeling, a computational fluid dynamics (CFD) modeling study has been performed for two different oxy-fuel furnaces. One is a lab-scale 0.8MW oxy-natural gas flame furnace whose detailed in......-flame measurement data are available; the other is a conventional 609MW utility boiler which is assumed to be operating under oxy-fuel combustion condition with dry flue gas recycle. A new model for gaseous radiative properties is developed, validated, and then implemented in the CFD simulations. The CFD results...... are compared to those based on the widely used model in literature, as well as the in-flame measurement data. The importance and advantage of the new model for gaseous radiative properties have been well demonstrated. Different combustion mechanisms are also implemented and compared in the CFD simulations...

  6. Advanced Diagnostics in Oxy-Fuel Combustion Processes

    DEFF Research Database (Denmark)

    Brix, Jacob; Toftegaard, Maja Bøg; Clausen, Sønnik

    , formed the basis of a publication and it is part of two PhD dissertations. The name of the conference the journal and the dissertations are listed below. - Joint Meeting of the Scandinavian-Nordic and French Sections of the Combustion Institute, Combustion of Char Particles under Oxy-Fuel Conditions......: Formation of NO and Particle Temperature, Copenhagen, 9-10 November 2009. - Brix J, Navascués LG, Joachim, Nielsen JB, Bonnek PL, Larsen HE, Clausen S, Glarborg P, Jensen AD, Oxy-Fuel Combustion of Coal Char: Particle Temperature and NO Formation, Submitted to Fuel on the 19th of November 2010. - Brix J......, Oxy-Fuel Combustion of Coal, Ph.D. Thesis, CHEC Research Centre – Technical University of Denmark, 2011. - Toftegaard, MB, OxyFuel Combustion of Coal and Biomass, Ph.D. Thesis, CHEC Research Centre – Technical University of Denmark, 2011. In addition two students projects have been carried out...

  7. Discovery of a Potent and Selective DGAT1 Inhibitor with a Piperidinyl-oxy-cyclohexanecarboxylic Acid Moiety.

    Science.gov (United States)

    He, Shuwen; Hong, Qingmei; Lai, Zhong; Yang, David X; Ting, Pauline C; Kuethe, Jeffrey T; Cernak, Timothy A; Dykstra, Kevin D; Sperbeck, Donald M; Wu, Zhicai; Yu, Yang; Yang, Ginger X; Jian, Tianying; Liu, Jian; Guiadeen, Deodial; Krikorian, Arto D; Sonatore, Lisa M; Wiltsie, Judyann; Liu, Jinqi; Gorski, Judith N; Chung, Christine C; Gibson, Jack T; Lisnock, JeanMarie; Xiao, Jianying; Wolff, Michael; Tong, Sharon X; Madeira, Maria; Karanam, Bindhu V; Shen, Dong-Ming; Balkovec, James M; Pinto, Shirly; Nargund, Ravi P; DeVita, Robert J

    2014-10-09

    We report the discovery of a novel series of DGAT1 inhibitors in the benzimidazole class with a piperdinyl-oxy-cyclohexanecarboxylic acid moiety. This novel series possesses significantly improved selectivity against the A2A receptor, no ACAT1 off-target activity at 10 μM, and higher aqueous solubility and free fraction in plasma as compared to the previously reported pyridyl-oxy-cyclohexanecarboxylic acid series. In particular, 5B was shown to possess an excellent selectivity profile by screening it against a panel of more than 100 biological targets. Compound 5B significantly reduces lipid excursion in LTT in mouse and rat, demonstrates DGAT1 mediated reduction of food intake and body weight in mice, is negative in a 3-strain Ames test, and appears to distribute preferentially in the liver and the intestine in mice. We believe this lead series possesses significant potential to identify optimized compounds for clinical development.

  8. dermaOXY skin assay: effect and evidence

    DEFF Research Database (Denmark)

    Menov, Lasse; Klösgen-Buchkremer, Beate Maria

    2015-01-01

    This text is a videnkupon report supported by the Danish Innovation Fonds and conducted by L.M. and B.K. for dermaOXY (by MedicTinedic ApS, Varde, Denmark). It involves two dermaOXY products: dermaOXY HYALURON SERUM and dermaOXY SYN SERUM. These are applied to the facial skin in combination...... with a 90 percent pure oxygen gas stream. Occasionally, the treatment is supported by low-level light exposure, prepared by mechanical microporation of skin or both. The dermaOXY skin improvement approach is used in treatments by clinics spread across 23 countries [1]. This text also includes an assessment...... of the instrument set DermaLab®Combo, which is used for the physical characterization of skin status after treatment. The report consists of four main parts, dedicated to 1. the properties of human skin 2. the anti-aging methods applied by the dermaOXY treatment 3. the analytical methods applied by derma...

  9. MORPHOLOGICAL CHANGES IN THE HIPPOCAMPUS OF RATS IN ACCELERATED AGING

    Directory of Open Access Journals (Sweden)

    K. Yu. Maksimova

    2014-01-01

    Full Text Available The aim of this work was the analysis of structural changes with age in the hippocampus of senescenceaccelerated OXYS rats when signs of accelerated brain aging are missing (age 14 days, developments (age 5 months, and active progresses (age 15 months. The study was performed on 15 OXYS rats and 15 Wistar rats (as a control. After dislocation, brains were dissected, fixed with 10% formalin, embedded in paraffin, and serially cut in coronal sections (5μm thickness. These sections were stained with Cresyl violet and examined with a photomicroscope (Carl Zeiss Axiostar plus, Germany. The total number of hippocampal pyramidal cells in the CA1, CA3 and the dentate gyrus regions were estimated in 14-dayold, 5and 15-month-old OXYS and Wistar rats (n = 5 on the 5 slices of each brain sections. The number of neurons with chromatolysis, hyperchromatic with darkly stained cytoplasm and shrunken neurons were calculated as degenerative neurons. The pictures obtained with the program Carl Zeiss Axio Vision 8.0 with increasing 10  100, determined the average area bodies and nuclei of neurons (mkm2. The significant structural changes of neurons in the CA1, CA3 and dentate gyrus regions of the hippocampus in OXYS rats at 5 month of age are revealed by light microscopy. This results indicates the early develop neurodegeneration in OXYS rats. The most pronounced morphological changes occur in the CA1 region of the hippocampus of OXYS rats and irreversible. The degenerative changes of neurons in the hippocampus increases by the age of 15 months. Morphometric analysis of the average area of bodies and the nuclei of hippocampal neurons in CA1, CA3 and the dentate gyrus regions of OXYS and Wistar rats at 14 days of age showed no significant interline differences. At 5 months of age in the CA1 region of the hippocampus of OXYS rats was determined a significantly lower average body size and nuclei of pyramidal neurons compared with Wistar rats. With age, these

  10. Crystal structure of 4-(4-meth-oxy-phen-oxy)benzaldehyde.

    Science.gov (United States)

    Schäfer, Andreas; Iovkova-Berends, Ljuba; Gilke, Stefan; Kossmann, Paul; Preut, Hans; Hiersemann, Martin

    2015-12-01

    The title compound, C14H12O3, was synthesized via the nucleophilic addition of 4-meth-oxy-phenol to 4-fluoro-benzaldehyde. The dihedral angle between the least-squares planes of the benzene rings is 71.52 (3)° and the C-O-C angle at the central O atom is 118.82 (8)°. In the crystal, weak C-H⋯O hydrogen bonds link the molecules to generate supra-molecular layers in the bc plane. The layers are linked by weak C-H⋯π inter-actions.

  11. Oxy-Fuel Combustion of Coal

    DEFF Research Database (Denmark)

    Brix, Jacob

    This Ph.D. thesis describes an experimental and modeling investigation of the thermal conversion of coal and an experimental investigation of the emission of NO from char combustion in O2/N2 and O2/CO2 atmospheres. The motivation for the work has been the prospective use of the technology “Oxy......-Fuel Combustion” as a mean of CO2 abatement in large scale energy conversion. Entrained Flow Reactor (EFR) experiments have been conducted in O2/N2 and O2/CO2 mixtures in the temperature interval 1173 K – 1673 K using inlet O2 concentrations between 5 – 28 vol. %. Bituminous coal has been used as fuel in all....... % it was found that char conversion rate was lowered in O2/CO2 compared to O2/N2. This is caused by the lower diffusion coefficient of O2 in CO2 (~ 22 %) that limits the reaction rate in zone III compared to combustion in O2/N2. Using char sampled in the EFR experiments ThermoGravimetric Analyzer (TGA...

  12. The development of an OxyHb animal model in mice and the study on OxyHb-induced apoptosis of mouse brain cells in vivo

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective On the basis of developing a new animal model for oxyhemoglobin(OxyHb)injection into subarachnoid space in mice,this research was to explore the temporal dependence and spatial distribution of OxyHb-induced apoptosis in the mouse brain cells in vivo and the mechanism of neurocyte injury induced by OxyHb.Methods The animal model for OxyHb injection into subarachnoid space in mice was developed.Mice were divided randomly into the experimental group(n=40)and the control group(n=35).The control group ...

  13. Optimization of Pressurized Oxy-Combustion with Flameless Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Malavasi, Massimo [Itea SpA, Gallarate, VA (Italy); Landegger, Gregory [ThermoEnergy Corporation, Worcester, MA (United States)

    2014-06-30

    Pressurized OxyECombustion is one of the most promising technologies for utility-scale power generation plants. Benefits include the ability to burn low rank coal and capture CO2. By increasing the flue gas pressure during this process, greater efficiencies are derived from increased quantity and quality of thermal energy recovery. UPA with modeling support from MIT and testing and data verification by Georgia Tech’s Research Center designed and built a 100 kW system capable of demonstrating pressurized oxyEcombustion using a flameless combustor. Wyoming PRB coal was run at 15 and 32 bar. Additional tests were not completed but sampled data demonstrated the viability of the technology over a broader range of operating pressures, Modeling results illustrated a flat efficiency curve over 20 bar, with optimum efficiency achieved at 29 bar. This resulted in a 33% (HHV) efficiency, a 5 points increase in efficiency versus atmospheric oxy-combustion, and a competitive cost of electricity plus greater CO2 avoidance costs then prior study’s presented. UPA’s operation of the bench-scale system provided evidence that key performance targets were achieved: flue gas sampled at the combustor outlet had non-detectable residual fly ashes, and low levels of SO3 and heavy-metal. These results correspond to prior pressurized oxy-combustion testing completed by IteaEEnel.

  14. Optimization of Pressurized Oxy4Combustion with Flameless Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Malavasi, Massimo; Landegger, Gregory

    2014-06-30

    Pressurized OxyECombustion is one of the most promising technologies for utilityEscale power generation plants. Benefits include the ability to burn low rank coal and capture C02. By increasing the flue gas pressure during this process, greater efficiencies are derived from increased quantity and quality of thermal energy recovery. UPA with modeling support from MIT and testing and data verification by Georgia Tech’s Research Center designed and built a 100kW system capable of demonstrating pressurized oxyEcombustion using a flameless combustor. Wyoming PRB coal was run at 15 and 32 bar. Additional tests were not completed but sampled data demonstrated the viability of the technology over a broader range of operating pressures, Modeling results illustrated a flat efficiency curve over 20 bar, with optimum efficiency achieved at 29 bar. This resulted in a 33% (HHV) efficiency, a 5 points increase in efficiency versus atmospheric oxyEcombustion, and a competitive cost of electricity plus greater C02 avoidance costs then prior study’s presented. UPA’s operation of the benchEscale system provided evidence that key performance targets were achieved: flue gas sampled at the combustor outlet had nonE detectable residual fly ashes, and low levels of SO3 and heavyEmetal. These results correspond to prior pressurized oxyEcombustion testing completed by IteaEEnel.

  15. 6,12,18,24-Tetra-meth-oxy-4,10,16,22-tetra-kis-[(meth-oxy-carbon-yl)meth-oxy]-2,8,14,20-tetra-kis-(2-phenyl-eth-yl)resorcin[4]arene.

    Science.gov (United States)

    Pansuriya, Pramod B; Friedrich, Holger B; Maguire, Glenn E M

    2012-01-01

    The title compound, C(76)H(80)O(16), is a macrocyclic structure. This novel resorcin[4]arene derivative has (meth-oxy-carbon-yl)meth-oxy 'head' groups on the upper rim. The compound has a C(2v) 'boat' geometry and there are a range of C-H⋯O contacts in the crystal structure.

  16. Nongray-gas Effects in Modeling of Large-scale Oxy-fuel Combustion Processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    , among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a large-scale utility boiler is numerically investigated......, the gray calculation of the oxy-fuel WSGGM remarkably over-predicts the radiative heat transfer to the furnace walls and under-predicts the gas temperature at the furnace exit plane, which also result in a higher incomplete combustion in the gray calculation. Moreover, the gray and non-gray calculations......Quite some studies have been conducted in order to implement oxy-fuel combustion with flue gas recycle in conventional utility boilers as an effective effort of carbon capture and storage. However, combustion under oxy-fuel conditions is significantly different from conventional air-fuel firing...

  17. Fireside Corrosion in Oxy-fuel Combustion of Coal

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R [National Energy Technology Laboratory; Tylczak, Joseph [National Energy Technology Laboratory; Meier, Gerald H [University of Pittsburgh; Lutz, Bradley [University of Pittsburgh; Jung, Keeyoung [Institute of Industrial Science and Technology, Korea; Mu, Nan; Yanar, Nazik M [University of Pittsburgh; Pettit, Frederick S [University of Pittsburgh; Zhu, Jingxi [Carnegie Mellon University; Wise, Adam [Carnegie Mellon University; Laughlin, David E. [Carnegie Mellon University; Sridhar, Seetharaman [Carnegie Mellon University

    2013-11-25

    Oxy-fuel combustion is burning a fuel in oxygen rather than air for ease of capture of CO2 from for reuse or sequestration. Corrosion issues associated with the environment change (replacement of much of the N2 with CO2 and higher sulfur levels) from air- to oxy-firing were examined. Alloys studied included model Fe–Cr alloys and commercial ferritic steels, austenitic steels, and nickel base superalloys. The corrosion behavior is described in terms of corrosion rates, scale morphologies, and scale/ash interactions for the different environmental conditions. Evidence was found for a hreshold for severe attack between 10-4 and 10-3 atm of SO3 at 700ºC.

  18. OxyContin, prescription opioid abuse and economic medicalization

    OpenAIRE

    Poitras, Geoffrey

    2012-01-01

    Geoffrey PoitrasFaculty of Business Administration, Simon Fraser University, Vancouver, BC, CanadaAbstract: This paper examines the relevance of OxyContin diversion and abuse to the economic medicalization of substance abuse and addiction. Given that medicalization is the general social process of nonmedical problems being transformed into medical problems, economic medicalization occurs where the motivation for the transformation is commercial profitability or, in a corporate context, achiev...

  19. Commercial Demonstration of Oxy-Coal Combustion Clean Power Technology

    Energy Technology Data Exchange (ETDEWEB)

    K.J. McCauley; K.C. Alexander; D.K. McDonald; N. Perrin; J.-P. Tranier [Babcock & Wilcox Power Generation Group (United Kingdom)

    2009-07-01

    Oxy-Coal Combustion is an advanced clean coal-based power generation technology with carbon capture and storage that will be Near Zero Emissions (NZEP), will capture and safely store CO{sub 2} in a geologic formation, and generate clean power for sale. This sustainable technology will utilize natural resources and support energy security goals. The unique benefits of oxy-coal combustion allow for near zero emissions of coal combustion products. The emissions of particulate matter, sulfur dioxide, nitrogen oxides and mercury will not only be below regulated levels, but all will be within the uncertainty of current industry measurement methods, essentially zero. This advanced technology will demonstrate all these reduced levels and will lead to commercially available NZEP plants for power generation. Since 1991, with the support of the US-DOE, Babcock & Wilcox Power Generation Group, Inc. (B&W PGG) and Air Liquide (AL) have worked to bring an advanced technology to the market for Carbon Capture and Storage (CCS) for coal-fired electric power generation plants. Oxy-coal combustion is now ready for at-scale demonstration leading directly to full scale commercialization and availability in the power generation marketplace. This paper will discuss the follow up of the results of the 30 MWth large pilot test program completed in December, 2008. This oxy-coal combustion technology has been through small lab pilot testing, large pilot testing, and a rigorous bottom-up integration and optimization analysis. Our paper will describe incorporating the best technological thinking for the integration of a modern PC-fired boiler, environmental control equipment, air separation unit (ASU) and compression purification unit (CPU). 5 refs., 3 figs.

  20. Effect of currently approved carriers and adjuvants on the pre-clinical efficacy of a conjugate vaccine against oxycodone in mice and rats.

    Directory of Open Access Journals (Sweden)

    Marco Pravetoni

    Full Text Available Vaccination against the highly abused prescription opioid oxycodone has shown pre-clinical efficacy for blocking oxycodone effects. The current study further evaluated a candidate vaccine composed of oxycodone derivatized at the C6 position (6OXY conjugated to the native keyhole limpet hemocyanin (nKLH carrier protein. To provide an oxycodone vaccine formulation suitable for human studies, we studied the effect of alternative carriers and adjuvants on the generation of oxycodone-specific serum antibody and B cell responses, and the effect of immunization on oxycodone distribution and oxycodone-induced antinociception in mice and rats. 6OXY conjugated to tetanus toxoid (TT or a GMP grade KLH dimer (dKLH was as effective as 6OXY conjugated to the nKLH decamer in mice and rats, while the 6OXY hapten conjugated to a TT-derived peptide was not effective in preventing oxycodone-induced antinociception in mice. Immunization with 6OXY-TT s.c. absorbed on alum adjuvant provided similar protection to 6OXY-TT administered i.p. with Freund's adjuvant in rats. The toll-like receptor 4 (TLR4 agonist monophosphoryl lipid A (MPLA adjuvant, alone or in combination with alum, offered no advantage over alum alone for generating oxycodone-specific serum antibodies or 6OXY-specific antibody secreting B cells in mice vaccinated with 6OXY-nKLH or 6OXY-TT. The immunogenicity of oxycodone vaccines may be modulated by TLR4 signaling since responses to 6OXY-nKLH in alum were decreased in TLR4-deficient mice. These data suggest that TT, nKLH and dKLH carriers provide consistent 6OXY conjugate vaccine immunogenicity across species, strains and via different routes of administration, while adjuvant formulations may need to be tailored to individual immunogens or patient populations.

  1. The OxyMask™ development and performance in healthy volunteers

    Directory of Open Access Journals (Sweden)

    James E Paul

    2008-12-01

    Full Text Available James E Paul1, Horia Hangan2, Julius Hajgato31Department of Anesthesia, McMaster University, Hamilton, ON, Canada; 2Faculty of Engineering, The University of Western Ontario, London, ON, Canada; 3Southmedic Inc., Barrie, ON, CanadaBackground: The OxyMask™ is a unique, open-style, oxygen mask that was originally developed in 2005. The original mask was modified, using computational fluid dynamics numerical simulations, with the goal of allowing it to produce a wider range of FiO2. This analysis was used to guide the modification of the mask shell and the location for the oxygen diffuser.Methods: The new OxyMask was attached to 10 healthy subjects and used to deliver escalating levels of oxygen (1.5, 2, 2.5, 3, 5, 10, 15, 20, 25 and 30 LPM for 90 seconds at each level and the resulting FiO2 was recorded (at the lips from 5 consecutive measurements at each oxygen flow rate.Results: Mean FiO2 was 25.4% at 1.5 LPM of oxygen, 30.1% at 2 LPM, 36.5% at 2.5 LPM, 41.8% at 3 LPM, 57.6% at 5 LPM, 74.4% at 10 LPM, and 80.1% at 15 LPM. Each FiO2 achieved at these escalating oxygen levels was significantly greater than all the previous levels. The mean FiO2 was 82.8 at 20 LPM, 84.2% at 25 LPM and 84.3% at 30 LPM. All of these values on average were not significantly greater than the FiO2 achieved with 15 LPM. In a few subjects a maximum FiO2 of 90% was reached.Conclusion: The original OxyMask was successfully modified so that the second generation of the mask can provide a wide range of FiO2, from 25% to 90%, while keeping its unique open design.Keywords: oxygen, oxygen masks, oxygen therapy, OxyMask™, OxyArm™, clinical trial, computational fluid dynamics (CFD, equipment design, biomedical engineering

  2. (E)-4-Meth-oxy-N'-(2,4,5-tri-meth-oxy-benzyl-idene)benzohydrazide hemihydrate.

    Science.gov (United States)

    Chantrapromma, Suchada; Boonnak, Nawong; Horkaew, Jirapa; Quah, Ching Kheng; Fun, Hoong-Kun

    2014-02-01

    The title compound crystallizes as a hemihydrate, C18H20N2O5·0.5H2O. The mol-ecule exists in an E conformation with respect to the C=N imine bond. The 4-meth-oxy-phenyl unit is disordered over two sets of sites with a refined occupancy ratio of 0.54 (2):0.46 (2). The dihedral angles between the benzene rings are 29.20 (9) and 26.59 (9)°, respectively, for the major and minor components of the 4-meth-oxy-substituted ring. All meth-oxy substituents lie close to the plane of the attached benzene rings [the Cmeth-yl-O-C-C torsion angles range from -4.0 (12) to 3.9 (2)°]. In the crystal, the components are linked into chains propagating along [001] via N-H⋯O and O-H⋯O hydrogen bonds and weak C-H⋯O inter-actions.

  3. (E)-2-Meth-oxy-9-(2-meth-oxy-9H-xanthen-9-yl-idene)-9H-xanthene.

    Science.gov (United States)

    Tian, Xiang-Yu; Song, Qin-Hua

    2013-01-01

    The title compound, C28H20O4, was synthesized by a bimolecular Zn-HCl reduction in glacial acetic acid using the meth-oxy-substituted xanthone as a starting material. The crystal structure shows that the 2,2'-meth-oxy-bixanthenyl-idene unit is an E-type conformation anti-folded conformer. The mol-ecule lies on an inversion center. The meth-oxy group is almost coplanar with the attached benzene ring, with a C-O-C-C torsion angle of 179.38 (14)°.

  4. 40 CFR 721.3020 - 1,1-Dimethylpropyl per-oxy-ester (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1,1-Dimethylpropyl per-oxy-ester (generic name). 721.3020 Section 721.3020 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3020 1,1-Dimethylpropyl per-oxy-ester (generic name). (a)...

  5. (E)-1-[2-Hy-droxy-4,6-bis-(meth-oxy-meth-oxy)phen-yl]-3-phenyl-prop-2-en-1-one.

    Science.gov (United States)

    Niu, Chao; Liu, Y Q; He, Y W; Aisa, H A

    2013-05-01

    The title compound, C19H20O6, consists of a tetra-substituted benzene ring with one substituent being an α,β-unsaturated cinnamoyl group, which forms an extended conjugated system in the mol-ecule. In addition, two meth-oxy-meth-oxy and one hy-droxy group are bonded to the central benzene ring. The dihedral angle between eh rings is 10.22 (10)°. An intra-molecular hydrogen bond is observed between the hy-droxy group and the carbonyl O atom. One of the meth-oxy-meth-oxy substituents is conformationally disordered over two sets of sites with site-occupation factors of 0.831 (3) and 0.169 (3).

  6. Representations of OxyContin in North American Newspapers and Medical Journals

    Directory of Open Access Journals (Sweden)

    Emma Whelan

    2011-01-01

    Full Text Available Following the approval of OxyContin (Purdue Pharma, Canada for medical use, the media began to report the use of OxyContin as a street drug, representing the phenomenon as a social problem. Meanwhile, the pain medicine community has criticized the inaccurate and one-sided media coverage of the OxyContin problem. The authors of this study aimed to contribute to an understanding of both sides of this controversy by analyzing the coverage of OxyContin in newspapers and medical journals. The analyses revealed inconsistent messages about the drug from physicians in the news media and in medical journals, which has likely contributed to the drug’s perception as a social problem. The authors suggest ways to address the lack of medical consensus surrounding OxyContin. The results of this study may help resolve the concerns and conflicts surrounding this drug and other opioids.

  7. Process simulation of oxy-combustion for maximization of energy output using ASPEN plus

    Directory of Open Access Journals (Sweden)

    Subhodeep Banerjee, Xiao Zhang, Suraj K. Puvvada, Ramesh K. Agarwal

    2014-01-01

    Full Text Available Oxy-fuel combustion is a next-generation combustion technology that shows promise to address the need of low-cost carbon capture from fossil fueled power plants. Oxy-fuel combustion requires expensive pre-processing in an air separation unit to separate pure oxygen from air for the combustion process, which reduces the overall efficiency of the process. This paper employs ASPEN Plus process simulation software to model a simple oxy-fuel combustor and investigates the effect of various parameters on the energy output. The composition of the flue gas is carefully examined. The results of this study provide a starting point for optimized oxy-fuel combustion operation for maximum energy output, which will be crucial for future deployment of oxy-fuel combustion technology.

  8. AQUATIC PHOTOLYSIS OF OXY-ORGANIC COMPOUNDS ADSORBED ON GOETHITE.

    Science.gov (United States)

    Goldberg, Marvin C.

    1985-01-01

    Organic materials that will not absorb light at wavelengths longer than 295 nanometers (the solar wavelength cutoff) may nevertheless, undergo electron transfer reactions initiated by light. These reactions occur when the organic materials are adsorbed as ligand complexes to the surface of iron oxy-hydroxide (goethite). The adsorbed materials can be either inner or outer coordination sphere complexes. Goethite was chosen as the iron oxyhydroxide surface because it has the highest thermodynamic stability of any of the oxyhydroxides in water and it can be synthesized easily, with high purity.

  9. Crystal structure of 4-meth-oxy-quinazoline.

    Science.gov (United States)

    El-Hiti, Gamal A; Smith, Keith; Hegazy, Amany S; Alshammari, Mohammed B; Kariuki, Benson M

    2014-12-01

    The title compound, C9H8N2O, is almost planar, with the C atom of the meth-oxy group deviating from the mean plane of the quinazoline ring system (r.m.s. deviation = 0.011 Å) by 0.068 (4) Å. In the crystal, mol-ecules form π-π stacks parallel to the b-axis direction [centroid-centroid separation = 3.5140 (18) Å], leading to a herringbone packing arrangement.

  10. Biomass co-firing under oxy-fuel conditions

    DEFF Research Database (Denmark)

    Álvarez, L.; Yin, Chungen; Riaza, J.

    2014-01-01

    to have favourable synergy effects in all the cases: it significantly improves the burnout and remarkably lowers NOx emissions. The reduced peak temperatures during co-firing can also help to mitigate deposition formation in real furnaces. Co-firing CO2-neutral biomass with coals under oxy-fuel conditions...... can achieve a below-zero CO2 emission if the released CO2 is captured and sequestered. The model-predicted burnout and gaseous emissions were compared against the experimental results. A very good agreement was observed, the differences in a range of ± 5–10% of the experimental values, which indicates...

  11. Role of oxyR from Sinorhizobium meliloti in Regulating the Expression of Catalases

    Institute of Scientific and Technical Information of China (English)

    Li LUO; Ming-Sheng QI; Shi-Yi YAO; Hai-Ping CHENG; Jia-Bi ZHU; Guan-Qiao YU

    2005-01-01

    The process of symbiotic nitrogen fixation results in the generation of reactive oxygen species such as the superoxide anion (O2-) and hydrogen peroxide (H2O2). The response of rhizobia to these toxic oxygen species is an important factor in nodulation and nitrogen fixation. In Sinorhizobium meliloti, one oxyR homologue and three catalase genes, katA, katB, and katC were detected by sequence analysis. This oxyR gene is located next to and divergently from katA on the chromosome. To investigate the possible roles of oxyR in regulating the expression of catalases at the transcriptional level in S. meliloti, an insertion mutant of this gene was constructed. The mutant was more sensitive and less adaptive to H2O2 than the wild type strain, and total catalase/peroxidase activity was reduced approximately fourfold with the OxyR mutation relative to controls. The activities of KatA and KatB and the expression of katA::lacZ and katB::lacZ promoter fusions were increased in the mutant strain compared with the parental strain grown in the absence of H2O2,indicating that katA and katB are repressed by OxyR. However, when exposed to H2O2, katA expression was also increased in both S. meliloti and Escherichia coli. When exposed to H2O2, OxyR is converted from a reduced to an oxidized form in E. coli. We concluded that the reduced form of OxyR functions as a repressor of katA and katB expression. Thus, in the presence of H2O2, reduced OxyR is converted to the oxidized form of OxyR that then results in increased katA expression. We further showed that oxyR expression is autoregulated via negative feedback.

  12. A New Oleanolic Acid Derivative against CCl4-Induced Hepatic Fibrosis in Rats

    Directory of Open Access Journals (Sweden)

    Hongjun Xiang

    2017-03-01

    Full Text Available A novel hepatoprotective oleanolic acid derivative, 3-oxours-oleana-9(11, 12-dien-28-oic acid (Oxy-Di-OA, has been reported. In previous studies, we found that Oxy-Di-OA presented the anti-HBV (Hepatitis B Virus activity (IC50 = 3.13 µg/mL. Remarkably, it is superior to lamivudine in the inhibition of the rebound of the viral replication rate. Furthermore, Oxy-Di-OA showed good performance of anti-HBV activity in vivo. Some studies showed that liver fibrosis may affiliate with HBV gene mutations. In addition, the anti-hepatic fibrosis activity of Oxy-Di-OA has not been studied. Therefore, we evaluated the protective effect of Oxy-Di-OA against carbon tetrachloride (CCl4-induced liver injury in rats. Daily intraperitoneally administration of Oxy-Di-OA prevented the development of CCl4-induced liver fibrosis, which was evidenced by histological study and immunohistochemical analysis. The entire experimental protocol lasted nine weeks. Oxy-Di-OA significantly suppressed the increases of plasma aspartate aminotransferase (AST and alanine aminotransferase (ALT levels (p < 0.05. Furthermore, Oxy-Di-OA could prevent expression of transforming growth factor β1 (TGF-β1. It is worth noting that the high-dose group Oxy-Di-OA is superior to bifendate in elevating hepatic function. Compared to the model group, Oxy-Di-OA in the high-dose group and low-dose group can significantly reduce the liver and spleen indices (p < 0.05. The acute toxicity test showed that LD50 and a 95% confidence interval (CIs value of Oxy-Di-OA were 714.83 mg/kg and 639.73–798.73 mg/kg via intraperitoneal injection in mice, respectively. The LD50 value of Oxy-Di-OA exceeded 2000 mg/kg via gavage in mice. In addition, a simple and rapid high performance liquid chromatography-ultraviolet (HPLC-UV method was developed and validated to study the pharmacokinetic characteristics of the compound. After single-dose oral administration, time to reach peak concentration of Oxy-Di-OA (Cmax

  13. Characterization of spontaneous mutation in the oxyR strain of Escherichia coli.

    Science.gov (United States)

    Yamamura, E; Nunoshiba, T; Kawata, M; Yamamoto, K

    2000-12-20

    Escherichia coli K-12 strain EY5, deficient in oxyR, was constructed to assess the role of oxyR and oxyR-regulated regulon in spontaneous mutagenesis. Mutagenesis was monitored by selecting two forward mutations of colicin B-sensitive to resistance and valine-sensitive to resistance, one base substitution mutation of rifampicin-sensitive to resistance and one reversion of argE3 his-4 to Arg(+) His(+). Deficiency of oxyR did not lead to the enhancement of spontaneous mutation frequencies of the four markers tested. By DNA sequence analysis, we determined 49 colicin B-resistant mutants derived from EY5 and found that 37% were base substitutions, 29% IS element insertions, 20% deletions, and 14% single base frameshifts. Among the base substitutions, G:C-->T:A transversions predominated followed by G:C-->A:T transitions and A:T-->T:A transversions. These spectra were essentially the same as those from oxyR(+) strains. The results indicate that oxyR and oxyR-regulated genes do not play a significant role in the defense against spontaneous mutagenesis.

  14. The development of an OxyHb animal model in mice and the study on OxyHb-induced apoptosis of mouse brain cells in vivo

    Institute of Scientific and Technical Information of China (English)

    Shi Wei; Wang Ruizhi; Huang Liyong; Sun Jianjun; Wang Fangru; Liu Chongxiao; Zhou Le; Guo Zhenyu; John H Zhang

    2008-01-01

    Objective On the basis of developing a new animal model for oxyhemoglobin (OxyHb) injection into subarachnoid space in mice, this research was to explore the temporal dependence and spatial distribution of OxyHb- induced apoptosis in the mouse brain cells in vivo and the mechanism of neurocyte injury induced by OxyHb. Methods The animal model for OxyHb injection into subarachnoid space in mice was developed. Mice were divided randomly into the experimental group (n=40) and the control group (n= 35). The control group received saline injection (50 μL ) and the experimental group received OxyHb injection (50 μL ), both into the subarachnoid space. The mice of the two groups were subdivided according to different postoperative time (3 h, 6 h, 12 h, 24 h and 48 h). The apoptosis or necrosis of cells was distinguished with microscopy (HE staining), transmission electron microscopy and TUNEL method. Results The distribution of apoptosis was mainly in the ipsilateral neocortex and bilateral hippocampal gyrus. The apoptotic mouse brain cells showed morphological changes in the experimental group by HE staining and transmission electron microscopy. The count of TUNEL-positive cells showed substantial increase in the experimental group, and there was a significant difference between the control and experimental groups, and the number of OxyHb- induced apoptotic cells decreased with time. Conclusion OxyHb in subarachnoid space in mice can induce apoptasis, but not necrosis of mouse brain cells in viro. The apoptotic brain cells show the pattern of temporal dependence and spatial distribution. It is suggested that the early treatment should be the method of first choice for treating the hemorrhagic brain injury.

  15. Plasma-enhanced growth, composition, and refractive index of silicon oxy-nitride films

    DEFF Research Database (Denmark)

    Mattsson, Kent Erik

    1995-01-01

    Secondary ion mass spectrometry and refractive index measurements have been carried out on silicon oxy-nitride produced by plasma-enhanced chemical vapor deposition (PECVD). Nitrous oxide and ammonia were added to a constant flow of 2% silane in nitrogen, to produce oxy-nitride films with atomic......-product. A model, that combine the chemical net reaction and the stoichiometric rules, is found to agree with measured deposition rates for given material compositions. Effects of annealing in a nitrogen atmosphere has been investigated for the 400 °C– 1100 °C temperature range. It is observed that PECVD oxy...

  16. Enantioselective synthesis of α-oxy amides via Umpolung amide synthesis.

    Science.gov (United States)

    Leighty, Matthew W; Shen, Bo; Johnston, Jeffrey N

    2012-09-19

    α-Oxy amides are prepared through enantioselective synthesis using a sequence beginning with a Henry addition of bromonitromethane to aldehydes and finishing with Umpolung Amide Synthesis (UmAS). Key to high enantioselection is the finding that ortho-iodo benzoic acid salts of the chiral copper(II) bis(oxazoline) catalyst deliver both diastereomers of the Henry adduct with high enantiomeric excess, homochiral at the oxygen-bearing carbon. Overall, this approach to α-oxy amides provides an innovative complement to alternatives that focus almost entirely on the enantioselective synthesis of α-oxy carboxylic acids.

  17. A new oxytocin-saporin cytotoxin for lesioning oxytocin-receptive neurons in the rat hindbrain.

    Science.gov (United States)

    Baskin, Denis G; Kim, Francis; Gelling, Richard W; Russell, Brian J; Schwartz, Michael W; Morton, Gregory J; Simhan, Hyagriv N; Moralejo, Daniel H; Blevins, James E

    2010-09-01

    Evidence suggests that release of oxytocin in the nucleus tractus solitarius (NTS) of the hindbrain from descending projections that originate in the paraventricular nucleus can inhibit food intake by amplifying the satiety response to cholecystokinin (CCK). To further evaluate this mechanism in rats, we used a novel cytotoxin, saporin conjugated to oxytocin (OXY-SAP), a compound designed to destroy cells that express oxytocin receptors (OXYr). OXY-SAP was injected directly into the NTS to lesion neurons that express OXYr and that are implicated in potentiating CCK's satiety effects. The control consisted of injection of saporin conjugated to a nonsense peptide. We found that OXY-SAP was cytotoxic to human uterine smooth muscle cells in vitro, demonstrating that OXY-SAP can lesion cells that express OXYr. Using laser capture microdissection and real-time quantitative PCR, we demonstrated that OXYr mRNA levels were reduced in the NTS after OXY-SAP administration. Moreover, we found that OXY-SAP attenuated the efficacy of CCK-8 to reduce food intake and blocked the actions of an OXYr antagonist to stimulate food intake. The findings suggest that OXY-SAP is an effective neurotoxin for in vivo elimination of cells that express OXYr and is potentially useful for studies to analyze central nervous system mechanisms that involve the action of oxytocin on food intake and other physiological processes.

  18. (E)-1-{4-[Bis(4-meth-oxy-phen-yl)meth-yl]piperazin-1-yl}-3-(4-eth-oxy-3-meth-oxy-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Zhong, Yan; Zhang, Xiao-Ping; Wu, Bin

    2012-04-01

    In the mol-ecule of the title compound, C(31)H(36)N(2)O(5), the piperazine ring displays a chair conformation. The dihedral angle between the benzene rings of the bis-(4-meth-oxy-phen-yl)methyl group is 83.42 (15)°. In the crystal, centrosymmetric-ally related mol-ecules are linked through pairs of C-H⋯O hydrogen bonds into dimers, generating an R(2) (2)(10) ring motif. The dimers are further connected into chains parallel to [2-10] by C-H⋯O hydrogen bonds involving the meth-oxy groups.

  19. Oxy-combustion of biomass in a circulating fluidized bed

    Science.gov (United States)

    Kosowska-Golachowska, Monika; Kijo-Kleczkowska, Agnieszka; Luckos, Adam; Wolski, Krzysztof; Musiał, Tomasz

    2016-03-01

    The objective of this study was to investigate combustion characteristics of biomass (willow, Salix viminalis) burnt in air and O2/CO2 mixtures in a circulating fluidized bed (CFB). Air and oxy-combustion characteristics of wooden biomass in CFB were supplemented by the thermogravimetric and differential thermal analyses (TGA/DTA). The results of conducted CFB and TGA tests show that the composition of the oxidizing atmosphere strongly influences the combustion process of biomass fuels. Replacing N2 in the combustion environment by CO2 caused slight delay (higher ignition temperature and lower maximum mass loss rate) in the combustion of wooden biomass. The combustion process in O2/CO2 mixtures at 30% and 40% O2 is faster and shorter than that at lower O2 concentrations.

  20. Oxy-combustion of biomass in a circulating fluidized bed

    Directory of Open Access Journals (Sweden)

    Kosowska-Golachowska Monika

    2016-03-01

    Full Text Available The objective of this study was to investigate combustion characteristics of biomass (willow, Salix viminalis burnt in air and O2/CO2 mixtures in a circulating fluidized bed (CFB. Air and oxy-combustion characteristics of wooden biomass in CFB were supplemented by the thermogravimetric and differential thermal analyses (TGA/DTA. The results of conducted CFB and TGA tests show that the composition of the oxidizing atmosphere strongly influences the combustion process of biomass fuels. Replacing N2 in the combustion environment by CO2 caused slight delay (higher ignition temperature and lower maximum mass loss rate in the combustion of wooden biomass. The combustion process in O2/CO2 mixtures at 30% and 40% O2 is faster and shorter than that at lower O2 concentrations.

  1. Oxi-Inflamm-Aging: a New Theory with Practical Implications

    Directory of Open Access Journals (Sweden)

    Ángel Julio Romero Cabrera

    2016-10-01

    Full Text Available Oxidative stress causes an impairment of the physiological systems essential for maintaining homeostasis, including the immune system. Immune dysregulation leads to a chronic low-grade inflammatory state in aging. This is the basis of the new integrative theory called oxy-inflamm-aging. The present article describes the foundations of this theory, the current research studies that support it, and its link with the pathogenesis of some age-related diseases. It is concluded that the adoption of a healthy lifestyle from an early age can contribute to a successful aging. The benefits of caloric restriction and antioxidant supplements are still under study in order to prevent oxidative stress and inflammation, and consequently achieve greater longevity and reduce the burden of age-associated diseases.

  2. The protective effect of bergamot oil extract on lecitine-like oxyLDL receptor-1 expression in balloon injury-related neointima formation.

    Science.gov (United States)

    Mollace, Vincenzo; Ragusa, Salvatore; Sacco, Iolanda; Muscoli, Carolina; Sculco, Francesca; Visalli, Valeria; Palma, Ernesto; Muscoli, Saverio; Mondello, Luigi; Dugo, Paola; Rotiroti, Domenicantonio; Romeo, Francesco

    2008-06-01

    Lectin-like oxyLDL receptor-1 (LOX-1) has recently been suggested to be involved in smooth muscle cell (SMC) proliferation and neointima formation in injured blood vessels. This study evaluates the effect of the nonvolatile fraction (NVF), the antioxidant component of bergamot essential oil (BEO), on LOX-1 expression and free radical generation in a model of rat angioplasty. Common carotid arteries injured by balloon angioplasty were removed after 14 days for histopathological, biochemical, and immunohistochemical studies. Balloon injury led to a significant restenosis with SMC proliferation and neointima formation, accompanied by increased expression of LOX-1 receptor, malondialdehyde and superoxide formation, and nitrotyrosine staining. Pretreatment of rats with BEO-NVF reduced the neointima proliferation together with free radical formation and LOX-1 expression in a dose-dependent manner. These results suggest that natural antioxidants may be relevant in the treatment of vascular disorders in which proliferation of SMCs and oxyLDL-related endothelial cell dysfunction are involved.

  3. Recovery Act: Oxy-Combustion Technology Development for Industrial-Scale Boiler Applications

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-01-01

    This Topical Report outlines guidelines and key considerations for design and operation of pulverized coal-fired boilers for oxy-combustion. The scope addressed includes only the boiler island, not the entire oxy-fired CO{sub 2} capture plant. These guidelines are primarily developed for tangential-fired boilers and focus on designs capable of dual air and oxy-fired operation. The guidelines and considerations discussed are applicable to both new units and existing boiler retrofits. These guidelines are largely based on the findings from the extensive 15 MW{sub th} pilot testing and design efforts conducted under this project. A summary level description is provided for each major aspect of boiler design impacted by oxy-combustion, and key considerations are discussed for broader application to different utility and industrial designs. Guidelines address the boiler system arrangement, firing system, boiler thermal design, ducting, materials, control system, and other key systems.

  4. GRH 12-01 Fireside Corrosion in Oxy-fuel Combustion Poster 0108

    Energy Technology Data Exchange (ETDEWEB)

    G. R. Holcomb; J. Tylczak; G. H. Meier; B. Lutz; K. Jung; N. Mu; N. M. Yanar; F. S. Pettit; J. Zhu; A. Wise; D. Laughlin; S. Sridhar

    2012-05-20

    The goals are to: (1) Achieve 90% CO{sub 2} capture at no more than a 35% increase in levelized cost of electricity of post-combustion capture for new and existing conventional coal-fired power plants; (2) Provide high-temperature corrosion information to aid in materials development and selection for oxy-fuel combustion; and (3) Identify corrosion mechanism and behavior differences between air- and oxy-firing.

  5. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    KAUST Repository

    Andersen, Myrrha E.

    2016-10-19

    Pulverized bituminous coal was burned in a 10. W externally heated entrained flow furnace under air-combustion and three oxy-combustion inlet oxygen conditions (28, 32, and 36%). Experiments were designed to produce flames with practically relevant stoichiometric ratios (SR. =1.2-1.4) and constant residence times (2.3. s). Size-classified fly ash samples were collected, and measurements focused on the soot, elemental carbon (EC), and organic carbon (OC) composition of the total and ultrafine (<0.6. μm) fly ash. Results indicate that although the total fly ash carbon, as measured by loss on ignition, was always acceptably low (<2%) with all three oxy-combustion conditions lower than air-combustion, the ultrafine fly ash for both air-fired and oxy-fired combustion conditions consists primarily of carbonaceous material (50-95%). Carbonaceous components on particles <0.6. μm measured by a thermal optical method showed that large fractions (52-93%) consisted of OC rather than EC, as expected. This observation was supported by thermogravimetric analysis indicating that for the air, 28% oxy, and 32% oxy conditions, 14-71% of this material may be OC volatilizing between 100. C and 550. C with the remaining 29-86% being EC/soot. However, for the 36% oxy condition, OC may comprise over 90% of the ultrafine carbon with a much smaller EC/soot contribution. These data were interpreted by considering the effects of oxy-combustion on flame attachment, ignition delay, and soot oxidation of a bituminous coal, and the effects of these processes on OC and EC emissions. Flame aerodynamics and inlet oxidant composition may influence emissions of organic hazardous air pollutants (HAPs) from a bituminous coal. During oxy-coal combustion, judicious control of inlet oxygen concentration and placement may be used to minimize organic HAP and soot emissions.

  6. Crystal structures of three 3,4,5-tri-meth-oxy-benzamide-based derivatives.

    Science.gov (United States)

    Gomes, Ligia R; Low, John Nicolson; Oliveira, Catarina; Cagide, Fernando; Borges, Fernanda

    2016-05-01

    The crystal structures of three benzamide derivatives, viz. N-(6-hy-droxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C16H25NO5, (1), N-(6-anilinohex-yl)-3,4,5-tri-meth-oxy-benzamide, C22H30N2O4, (2), and N-(6,6-di-eth-oxy-hex-yl)-3,4,5-tri-meth-oxy-benzamide, C20H33NO6, (3), are described. These compounds differ only in the substituent at the end of the hexyl chain and the nature of these substituents determines the differences in hydrogen bonding between the mol-ecules. In each mol-ecule, the m-meth-oxy substituents are virtually coplanar with the benzyl ring, while the p-meth-oxy substituent is almost perpendicular. The carbonyl O atom of the amide rotamer is trans related with the amidic H atom. In each structure, the benzamide N-H donor group and O acceptor atoms link the mol-ecules into C(4) chains. In 1, a terminal -OH group links the mol-ecules into a C(3) chain and the combined effect of the C(4) and C(3) chains is a ribbon made up of screw related R 2 (2)(17) rings in which the ⋯O-H⋯ chain lies in the centre of the ribbon and the tri-meth-oxy-benzyl groups forms the edges. In 2, the combination of the benzamide C(4) chain and the hydrogen bond formed by the terminal N-H group to an O atom of the 4-meth-oxy group link the mol-ecules into a chain of R 2 (2)(17) rings. In 3, the mol-ecules are linked only by C(4) chains.

  7. Crystal structure of 3,4-di-meth-oxy-phenol.

    Science.gov (United States)

    Mills-Robles, Heather A; Desikan, Vasumathi; Golen, James A; Manke, David R

    2015-12-01

    The title compound, C8H10O3, has two planar mol-ecules in the asymmetric unit possessing mean deviations from planarity of 0.051 and 0.071 Å. In the crystal, there are two distinct infinite chains, both along [010]. The chains are formed by O-H⋯O inter-actions between the phenol and both the 3-meth-oxy and the 4-meth-oxy groups.

  8. 鼠疫菌OxyR调控子蛋白对dps的转录调控机制%Transcriptional regulation of dps by OxyR protein in Yersinia pestis

    Institute of Scientific and Technical Information of China (English)

    倪斌; 张义全; 黄新祥; 杨瑞馥; 周冬生

    2013-01-01

    [Objective] To study the transcriptional regulation mechanism of dps by OxyR in Yersinia pestis.[Methods]Total RNAs were extracted from the wide-type (WT) strain and the oxyR null mutant (ΔoxyR).Primer extension assay was used to detect the promoter activity (the amount of primer extension product) of dps in WT and that in ΔoxyR.Then,quantitative RT-PCR was done to calculate the transcriptional variation of dps between the WT and ΔoxyR.The entire promoter-proximal region of the dps gene was amplified by PCR from Y.pestis strain 201.Over-expressed His-OxyR was purified under native conditions with nickel loaded HiTrap Chelating Sepharose columns (Amersham).Then,the electrophoretic mobility shift assay (EMSA) was applied to analyze the DNA-binding activity of His-OxyR to dps promoter region in vitro.Finally,Escherichia coli OxyR consensus was deployed to predict the OxyR binding site to dps promoter region.[Results] The primer extension assay detected only one transcriptional start site located at 40bp uptream of dps,whose transcript was under positive regulation by OxyR.The bioinformatics analysis indicated that His-OxyR bound to a single region from 111bp to 78bp upstream of dps.[Conclusion] The transcription of dps was directly activated by OxyR in Yersinia pestis.%[目的]利用分子生物学实验研究鼠疫菌调控子OxyR对dps的转录调控机制.[方法]提取鼠疫菌野生株(WT)和oxyR突变株(ΔoxyR)的总RNA,采用引物延伸实验研究dps的转录起始位点,并根据产物的丰度判断OxyR对dps的调控关系.进一步采用实时定量RT-PCR的方法验证OxyR对dps的调控关系.PCR扩增dps的整个启动子区DNA序列,并纯化His-OxyR蛋白,通过凝胶阻滞实验(EMSA)验证OxyR对dps启动子区是否具有直接的相互作用.利用大肠杆菌OxyR识别基序,预测鼠疫菌OxyR对dps启动子区的结合位点,从而得出鼠疫菌OxyR对dps的转录调控机制.[结果]鼠疫菌dps有一个转录起始位点G(-40)(

  9. Sulfur emission from Victorian brown coal under pyrolysis, oxy-fuel combustion and gasification conditions.

    Science.gov (United States)

    Chen, Luguang; Bhattacharya, Sankar

    2013-02-05

    Sulfur emission from a Victorian brown coal was quantitatively determined through controlled experiments in a continuously fed drop-tube furnace under three different atmospheres: pyrolysis, oxy-fuel combustion, and carbon dioxide gasification conditions. The species measured were H(2)S, SO(2), COS, CS(2), and more importantly SO(3). The temperature (873-1273 K) and gas environment effects on the sulfur species emission were investigated. The effect of residence time on the emission of those species was also assessed under oxy-fuel condition. The emission of the sulfur species depended on the reaction environment. H(2)S, SO(2), and CS(2) are the major species during pyrolysis, oxy-fuel, and gasification. Up to 10% of coal sulfur was found to be converted to SO(3) under oxy-fuel combustion, whereas SO(3) was undetectable during pyrolysis and gasification. The trend of the experimental results was qualitatively matched by thermodynamic predictions. The residence time had little effect on the release of those species. The release of sulfur oxides, in particular both SO(2) and SO(3), is considerably high during oxy-fuel combustion even though the sulfur content in Morwell coal is only 0.80%. Therefore, for Morwell coal utilization during oxy-fuel combustion, additional sulfur removal, or polishing systems will be required in order to avoid corrosion in the boiler and in the CO(2) separation units of the CO(2) capture systems.

  10. Determination of a peroxisome proliferator-activated receptor γ agonist, 1-(trans-methylimino-N-oxy)-6-(2-morpholinoethoxy-3-phenyl-1H-indene-2-carboxylic acid ethyl ester (KR-62980) in rat plasma by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Kim, Min-Sun; Song, Jin Sook; Roh, Hyeongjin; Park, Jong-Shik; Ahn, Jin Hee; Ahn, Sung-Hoon; Bae, Myung Ae

    2011-01-01

    A novel peroxisome proliferator-activated receptor γ (PPARγ) agonist, KR-62980, was determined by liquid-liquid extraction with ethyl acetate and liquid chromatography-tandem mass spectrometry (LC/MS/MS) in rat plasma. In order to evaluate the pharmacokinetics of KR-62980, a reliable, selective and sensitive high-performance liquid chromatographic method with electrospray ionization tandem mass spectrometry was developed for the quantification of KR-62980 in rat plasma. KR-62980 and imipramine (IS) were separated on Hypersil GOLD C18 column with a mixture of acetonitrile-ammonium formate (10mM) (80:20, v/v) as mobile phase. The ion transitions monitored were m/z 437.2 → 114.2 for KR-62980, m/z 281.3 → 86.1 for imipramine in multiple reaction monitoring (MRM) mode. The percent recoveries of KR-62980 and imipramine were 90.1 and 98.4% from rat plasma, respectively. The linear dynamic range extended from 0.01 to 10 μg/ml with a correlation coefficient (R(2)) greater than 0.99 and the lower limit of quantification was 0.01 μg/ml. The mean of intra- and inter-assay precisions was 2.1 and 9.3%. The method was validated and successfully applied to the pharmacokinetic study of KR-62980 in rat.

  11. Oxy-combustion of high water content fuels

    Science.gov (United States)

    Yi, Fei

    As the issues of global warming and the energy crisis arouse extensive concern, more and more research is focused on maximizing energy efficiency and capturing CO2 in power generation. To achieve this, in this research, we propose an unconventional concept of combustion - direct combustion of high water content fuels. Due to the high water content in the fuels, they may not burn under air-fired conditions. Therefore, oxy-combustion is applied. Three applications of this concept in power generation are proposed - direct steam generation for the turbine cycle, staged oxy-combustion with zero flue gas recycle, and oxy-combustion in a low speed diesel-type engine. The proposed processes could provide alternative approaches to directly utilize fuels which intrinsically have high water content. A large amount of energy to remove the water, when the fuels are utilized in a conventional approach, is saved. The properties and difficulty in dewatering high water content fuels (e.g. bioethanol, microalgae and fine coal) are summarized. These fuels include both renewable and fossil fuels. In addition, the technique can also allow for low-cost carbon capture due to oxy-combustion. When renewable fuel is utilized, the whole process can be carbon negative. To validate and evaluate this concept, the research focused on the investigation of the flame stability and characteristics for high water content fuels. My study has demonstrated the feasibility of burning fuels that have been heavily diluted with water in a swirl-stabilized burner. Ethanol and 1-propanol were first tested as the fuels and the flame stability maps were obtained. Flame stability, as characterized by the blow-off limit -- the lowest O2 concentration when a flame could exist under a given oxidizer flow rate, was determined as a function of total oxidizer flow rate, fuel concentration and nozzle type. Furthermore, both the gas temperature contour and the overall ethanol concentration in the droplets along the

  12. Effects of an oxycodone conjugate vaccine on oxycodone self-administration and oxycodone-induced brain gene expression in rats.

    Directory of Open Access Journals (Sweden)

    Marco Pravetoni

    Full Text Available Prescription opioid abuse is an increasing public health concern in the USA. A vaccine comprising a hapten (OXY conjugated to the carrier protein keyhole limpet hemocyanin (OXY-KLH has been shown to attenuate the antinociceptive effects of oxycodone. Here, the vaccine's ability to prevent acquisition of intravenous (i.v. oxycodone self-administration was studied in rats. Effects of vaccination on oxycodone-induced changes in the expression of several genes within the mesolimbic system, which are regulated by chronic opiate use, were also examined. Vaccination with OXY-KLH reduced the proportion of rats acquiring i.v. self-administration of oxycodone under a fixed ratio (FR 3 schedule of reinforcement compared to control rats immunized with the unconjugated KLH carrier protein. Vaccination significantly reduced the mean number of infusions at FR3, total number of infusions, and total oxycodone intake during the entire protocol. Compared to oxycodone self-administering control rats immunized with the carrier alone, rats vaccinated with the OXY-KLH immunogen showed increased levels of adenylate cyclase 5 (Adcy5 and decreased levels of early growth response protein 2 (Egr2 and the early immediate gene c-Fos in the striatum. These data suggest that vaccination with OXY-KLH can attenuate the reinforcing effects of oxycodone at a clinically-relevant exposure level. Analysis of mRNA expression identified some addiction-relevant markers that may be of interest in understanding oxycodone effects or the protection provided by vaccination.

  13. Regulation of minD by oxyR in Neisseria gonorrhoeae.

    Science.gov (United States)

    Parti, Rajinder P; Horbay, Monique A; Liao, Mingmin; Dillon, Jo-Anne R

    2013-06-01

    In Neisseria gonorrhoeae, cytokinesis involves Escherichia coli homologues of minC, minD and minE which are encoded as part of a min operon. MinD, a 30 kD protein component of the MinC-MinD septum inhibitory complex, together with MinE, mediates cell division site selection. Gonococci mutated in minD display aberrant cytokinesis, abnormal morphology, defective microcolony formation and virulence. minD is 274 bp upstream of oxyR, another min operon gene in N. gonorrhoeae, which encodes a redox-responsive transcriptional regulator implicated in responses to oxidative stress. In this study, we aimed to examine the oxyR-mediated regulation of minD. We observed the cotranscription of oxyR with the minCDE gene cluster. The mutation of oxyR resulted in non-midline formation of the division septum, anomalous DNA segregation, and increased aggregation of bacterial cells. qRT-PCR and Western Blot analysis revealed upregulation of minD in an oxyR mutant as compared to its isogenic wild-type N. gonorrhoeae strain in stationary phase. Furthermore, the exposure to oxidative stress in the form of H2O2 increased MinD expression levels in wild-type N. gonorrhoeae. Using β-galactosidase activity-based promoter assays, we found that oxyR negatively regulates the promoter region (PminD) upstream of minD. Our results demonstrate the involvement of oxyR in cell division and minD expression in N. gonorrhoeae.

  14. Effective Construction of High-quality Iron Oxy-hydroxides and Co-doped Iron Oxy-hydroxides Nanostructures: Towards the Promising Oxygen Evolution Reaction Application

    Science.gov (United States)

    Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping

    2017-01-01

    Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co0.54Fe0.46OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co0.54Fe0.46OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal−air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application. PMID:28272443

  15. Effective Construction of High-quality Iron Oxy-hydroxides and Co-doped Iron Oxy-hydroxides Nanostructures: Towards the Promising Oxygen Evolution Reaction Application.

    Science.gov (United States)

    Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping

    2017-03-08

    Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co0.54Fe0.46OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co0.54Fe0.46OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application.

  16. Oxy-coal combustion in an entrained flow reactor: Application of specific char and volatile combustion and radiation models for oxy-firing conditions

    DEFF Research Database (Denmark)

    Álvarez, L.; Yin, Chungen; Riaza, J.

    2013-01-01

    implemented in CFD (Computational Fluid Dynamics) simulations of combustion of three coals under air-firing and various oxy-firing (21-35% vol O2 in O2/CO2 mixture) conditions in an EFR (entrained flow reactor). The predicted coal burnouts and gaseous emissions were compared against experimental results...

  17. Rats

    Directory of Open Access Journals (Sweden)

    Alexey Kondrashov

    2012-01-01

    Full Text Available We aimed to perform a chemical analysis of both Alibernet red wine and an alcohol-free Alibernet red wine extract (AWE and to investigate the effects of AWE on nitric oxide and reactive oxygen species production as well as blood pressure development in normotensive Wistar Kyoto (WKY and spontaneously hypertensive rats (SHRs. Total antioxidant capacity together with total phenolic and selected mineral content was measured in wine and AWE. Young 6-week-old male WKY and SHR were treated with AWE (24,2 mg/kg/day for 3 weeks. Total NOS and SOD activities, eNOS and SOD1 protein expressions, and superoxide production were determined in the tissues. Both antioxidant capacity and phenolic content were significantly higher in AWE compared to wine. The AWE increased NOS activity in the left ventricle, aorta, and kidney of SHR, while it did not change NOS activity in WKY rats. Similarly, increased SOD activity in the plasma and left ventricle was observed in SHR only. There were no changes in eNOS and SOD1 expressions. In conclusion, phenolics and minerals included in AWE may contribute directly to increased NOS and SOD activities of SHR. Nevertheless, 3 weeks of AWE treatment failed to affect blood pressure of SHR.

  18. Dynamic-Stability Characteristics of Premixed Methane Oxy-Combustion

    KAUST Repository

    Shroll, Andrew P.

    2012-01-01

    This work explores the dynamic stability characteristics of premixed CH 4/O 2/CO 2 mixtures in a 50 kW swirl stabilized combustor. In all cases, the methane-oxygen mixture is stoichiometric, with different dilution levels of carbon dioxide used to control the flame temperature (T ad). For the highest T ad\\'s, the combustor is unstable at the first harmonic of the combustor\\'s natural frequency. As the temperature is reduced, the combustor jumps to fundamental mode and then to a low-frequency mode whose value is well below the combustor\\'s natural frequency, before eventually reaching blowoff. Similar to the case of CH 4/air mixtures, the transition from one mode to another is predominantly a function of the T ad of the reactive mixture, despite significant differences in laminar burning velocity and/or strained flame consumption speed between air and oxy-fuel mixtures for a given T ad. High speed images support this finding by revealing similar vortex breakdown modes and thus similar turbulent flame geometries that change as a function of flame temperature. Copyright © 2012 American Society of Mechanical Engineers.

  19. Biphasic oxidation of oxy-hemoglobin in bloodstains.

    Directory of Open Access Journals (Sweden)

    Rolf H Bremmer

    Full Text Available BACKGROUND: In forensic science, age determination of bloodstains can be crucial in reconstructing crimes. Upon exiting the body, bloodstains transit from bright red to dark brown, which is attributed to oxidation of oxy-hemoglobin (HbO(2 to met-hemoglobin (met-Hb and hemichrome (HC. The fractions of HbO(2, met-Hb and HC in a bloodstain can be used for age determination of bloodstains. In this study, we further analyze the conversion of HbO(2 to met-Hb and HC, and determine the effect of temperature and humidity on the conversion rates. METHODOLOGY: The fractions of HbO(2, met-Hb and HC in a bloodstain, as determined by quantitative analysis of optical reflectance spectra (450-800 nm, were measured as function of age, temperature and humidity. Additionally, Optical Coherence Tomography around 1300 nm was used to confirm quantitative spectral analysis approach. CONCLUSIONS: The oxidation rate of HbO(2 in bloodstains is biphasic. At first, the oxidation of HbO(2 is rapid, but slows down after a few hours. These oxidation rates are strongly temperature dependent. However, the oxidation of HbO(2 seems to be independent of humidity, whereas the transition of met-Hb into HC strongly depends on humidity. Knowledge of these decay rates is indispensable for translating laboratory results into forensic practice, and to enable bloodstain age determination on the crime scene.

  20. Resilience and ductility of Oxy-fuel HAZ cut

    Directory of Open Access Journals (Sweden)

    A. Martín-Meizoso,

    2014-10-01

    Full Text Available Cutting processes affect the material to a deeper or shallower attached-to-the-cut zone. Its microstructure, its hardness and mechanical properties are changed. Also the cutting process introduces surface roughness and residual stresses. In most cases it is recommended to remove this region by grinding, in order to keep a smoother surface, free from the above mentioned effects. This work presents the characterization results of the Heat Affected Zone (HAZ of a steel plate of grade S460M, with a thickness of 25 mm, cut by flame oxyfuel gas cutting. The HAZ microstructure is observed (and the depth of the HAZ measured, the hardness profile and the stress vs. strain curves until fracture are measured by testing micro-tensile samples, instrumented with strain gauges. Micro-Tensile specimens are 200 microns in thickness and were obtained from layers of the HAZ at different distances from the oxy-fuel cut. The obtained stress-strain curves are compared with the hardness measurements and the observed metallography.

  1. Structural and redox behavior of OxyVita, a zero-linked polymeric hemoglobin: comparison with natural acellular polymeric hemoglobins.

    Science.gov (United States)

    Harrington, John P; Orlik, Kseniya; Orlig, Kseniya; Zito, Samantha L; Wollocko, Jacek; Wollocko, Hanna

    2010-04-01

    A zero-linked polymeric hemoglobin (OxyVita Hb) has been developed for application as an acellular therapeutic hemoglobin-based-oxygen-carrier (HBOC). For effective and safe oxygen binding, transport and delivery, an HBOC must meet essential molecular requirements related to its structural integrity and redox stability. OxyVita is a super polymer possessing an average M.wt. of 17 x 10(6) Da. Structural integrity was determined by unfolding studies of OxyVita in the presence of increasing concentrations of urea. The unfolding midpoints (D(1/2)) of different preparations of OxyVita (solution and powder forms) were compared to Lumbricus Hb (LtHb) and Arenicola Hb (ArHb), natural acellular polymeric hemoglobins, which are serving as models for an effective and safe acellular HBOC. Reduction studies of OxyVita Hb using endogenous reducing agents were also investigated. Results from these studies indicate that: 1) OxyVita Hb exhibits greater resistance to conformational change than either LtHb or ArHb in the reduced (oxyHb) state; and 2) the reduction of met OxyVita Hb to oxyHb occurs slowly in the presence of either ascorbic acid (70% reduction in 560 min.) or beta-NADH (40% reduction in 90 min.). These studies provide consistent evidence that OxyVita Hb possesses physiochemical properties that exhibit structural integrity and redox behavior necessary for functioning as an effective and safe HBOC within clinical applications. These results are in agreement with observations made by other investigators as to the reduction in heme-loss of OxyVita Hb, essential for the reversible binding/release of molecular oxygen within the circulatory system.

  2. Novel Supercritical Carbon Dioxide Power Cycle Utilizing Pressured Oxy-combustion in Conjunction with Cryogenic Compression

    Energy Technology Data Exchange (ETDEWEB)

    Brun, Klaus; McClung, Aaron; Davis, John

    2014-03-31

    The team of Southwest Research Institute® (SwRI) and Thar Energy LLC (Thar) applied technology engineering and economic analysis to evaluate two advanced oxy-combustion power cycles, the Cryogenic Pressurized Oxy-combustion Cycle (CPOC), and the Supercritical Oxy-combustion Cycle. This assessment evaluated the performance and economic cost of the two proposed cycles with carbon capture, and included a technology gap analysis of the proposed technologies to determine the technology readiness level of the cycle and the cycle components. The results of the engineering and economic analysis and the technology gap analysis were used to identify the next steps along the technology development roadmap for the selected cycle. The project objectives, as outlined in the FOA, were 90% CO{sub 2} removal at no more than a 35% increase in cost of electricity (COE) as compared to a Supercritical Pulverized Coal Plant without CO{sub 2} capture. The supercritical oxy-combustion power cycle with 99% carbon capture achieves a COE of $121/MWe. This revised COE represents a 21% reduction in cost as compared to supercritical steam with 90% carbon capture ($137/MWe). However, this represents a 49% increase in the COE over supercritical steam without carbon capture ($80.95/MWe), exceeding the 35% target. The supercritical oxy-combustion cycle with 99% carbon capture achieved a 37.9% HHV plant efficiency (39.3% LHV plant efficiency), when coupling a supercritical oxy-combustion thermal loop to an indirect supercritical CO{sub 2} (sCO{sub 2}) power block. In this configuration, the power block achieved 48% thermal efficiency for turbine inlet conditions of 650°C and 290 atm. Power block efficiencies near 60% are feasible with higher turbine inlet temperatures, however a design tradeoff to limit firing temperature to 650°C was made in order to use austenitic stainless steels for the high temperature pressure vessels and piping and to minimize the need for advanced turbomachinery features

  3. A Reduced Order Model for the Design of Oxy-Coal Combustion Systems

    Directory of Open Access Journals (Sweden)

    Steven L. Rowan

    2015-01-01

    Full Text Available Oxy-coal combustion is one of the more promising technologies currently under development for addressing the issues associated with greenhouse gas emissions from coal-fired power plants. Oxy-coal combustion involves combusting the coal fuel in mixtures of pure oxygen and recycled flue gas (RFG consisting of mainly carbon dioxide (CO2. As a consequence, many researchers and power plant designers have turned to CFD simulations for the study and design of new oxy-coal combustion power plants, as well as refitting existing air-coal combustion facilities to oxy-coal combustion operations. While CFD is a powerful tool that can provide a vast amount of information, the simulations themselves can be quite expensive in terms of computational resources and time investment. As a remedy, a reduced order model (ROM for oxy-coal combustion has been developed to supplement the CFD simulations. With this model, it is possible to quickly estimate the average outlet temperature of combustion flue gases given a known set of mass flow rates of fuel and oxidant entering the power plant boiler as well as determine the required reactor inlet mass flow rates for a desired outlet temperature. Several cases have been examined with this model. The results compare quite favorably to full CFD simulation results.

  4. Oxy-Combustion Burner and Integrated Pollutant Removal Research and Development Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Mark Schoenfield; Manny Menendez; Thomas Ochs; Rigel Woodside; Danylo Oryshchyn

    2012-09-30

    A high flame temperature oxy-combustion test facility consisting of a 5 MWe equivalent test boiler facility and 20 KWe equivalent IPR® was constructed at the Hammond, Indiana manufacturing site. The test facility was operated natural gas and coal fuels and parametric studies were performed to determine the optimal performance conditions and generated the necessary technical data required to demonstrate the technologies are viable for technical and economic scale-up. Flame temperatures between 4930-6120F were achieved with high flame temperature oxy-natural gas combustion depending on whether additional recirculated flue gases are added to balance the heat transfer. For high flame temperature oxy-coal combustion, flame temperatures in excess of 4500F were achieved and demonstrated to be consistent with computational fluid dynamic modeling of the burner system. The project demonstrated feasibility and effectiveness of the Jupiter Oxygen high flame temperature oxy-combustion process with Integrated Pollutant Removal process for CCS and CCUS. With these technologies total parasitic power requirements for both oxygen production and carbon capture currently are in the range of 20% of the gross power output. The Jupiter Oxygen high flame temperature oxy-combustion process has been demonstrated at a Technology Readiness Level of 6 and is ready for commencement of a demonstration project.

  5. 21 CFR 177.1637 - Poly(oxy-1,2-ethanediyloxycarbonyl-2,6-naphthalenediylcarbonyl) resins.

    Science.gov (United States)

    2010-04-01

    ...-naphthalenediylcarbonyl) resins. 177.1637 Section 177.1637 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Poly(oxy-1,2-ethanediyloxycarbonyl-2,6-naphthalenediylcarbonyl) resins. Poly(oxy-1,2-ethanediyloxycarbonyl-2,6-naphthalenediylcarbonyl) resins identified in paragraph (a) of this section may be safely...

  6. A Model for Nitrogen Chemistry in Oxy-Fuel Combustion of Pulverized Coal

    DEFF Research Database (Denmark)

    Hashemi, Hamid; Hansen, Stine; Toftegaard, Maja Bøg;

    2011-01-01

    , heating and devolatilization of particles, and gas–solid reactions. The model is validated by comparison with entrained flow reactor results from the present work and from the literature on pulverized coal combustion in O2/CO2 and air, covering the effects of fuel, mixing conditions, temperature......In this work, a model for the nitrogen chemistry in the oxy-fuel combustion of pulverized coal has been developed. The model is a chemical reaction engineering type of model with a detailed reaction mechanism for the gas-phase chemistry, together with a simplified description of the mixing of flows......, stoichiometry, and inlet NO level. In general, the model provides a satisfactory description of NO formation in air and oxy-fuel combustion of coal, but under some conditions, it underestimates the impact on NO of replacing N2 with CO2. According to the model, differences in the NO yield between the oxy...

  7. Effects of (Oxy-)Fluorination on Various High-Performance Yarns.

    Science.gov (United States)

    Kruppke, Iris; Bartusch, Matthias; Hickmann, Rico; Hund, Rolf-Dieter; Cherif, Chokri

    2016-01-01

    In this work, typical high-performance yarns are oxy-fluorinated, such as carbon fibers, ultra-high-molecular-weight polyethylene, poly(p-phenylene sulfide) and poly(p-phenylene terephthalamide). The focus is on the property changes of the fiber surface, especially the wetting behavior, structure and chemical composition. Therefore, contact angle, XPS and tensile strength measurements are performed on treated and untreated fibers, while SEM is utilized to evaluate the surface structure. Different results for the fiber materials are observed. While polyethylene exhibits a relevant impact on both surface and bulk properties, polyphenylene terephthalamide and polyphenylene sulfide are only affected slightly by (oxy-)fluorination. The wetting of carbon fiber needs higher treatment intensities, but in contrast to the organic fibers, even its textile-physical properties are enhanced by the treatment. Based on these findings, the capability of (oxy-)fluorination to improve the adhesion of textiles in fiber-reinforced composite materials can be derived.

  8. Bis{bis-[1-meth-oxy-2-(2-meth-oxy-eth-oxy)ethane-κ(3) O,O',O'']sodium} 1,1,2,2-tetra-phenyl-ethane-1,2-diide.

    Science.gov (United States)

    Minyaev, Mikhail E; Ellis, John E

    2014-07-01

    Crystals of the title salt, [Na(C6H14O3)2]2(C26H20), were grown from a tetra-hydro-furan/diglyme/Et2O solvent mixture [diglyme is 1-meth-oxy-2-(2-meth-oxy-eth-oxy)ethane]. The cations and dianion are separated in the crystal structure, unlike in the other three structurally characterized dialkali metal tetra-phenyl-ethyl-ene salts. The asymmetric unit contains one [Na(diglyme)2](+) cation and one half of the [Ph2CCPh2](2-) dianion. The latter lies on a twofold rotation axis. C-C bond-length redistribution displays that excessive electron density of the dianion is predominantly located at the C atoms of a former double bond and at all eight ortho positions. The studied crystal was a twin, with the ratio of two major components being 0.2143 (9):0.7857 (9). The twin operation is a twofold rotation around the a axis.

  9. A study of oxy-coal combustion with steam addition and biomass blending by thermogravimetric analysis

    OpenAIRE

    Gil Matellanes, María Victoria; Riaza Benito, Juan; Álvarez González, Lucía; Pevida García, Covadonga; Pis Martínez, José Juan; Rubiera González, Fernando

    2011-01-01

    The thermal characteristics of pulverized coal have been studied under oxy-fuel combustion conditions using non-isothermal thermogravimetric analysis (TG). The atmospheres used were 21%O2/79%N2, 21%O2/79%CO2, 30%O2/70%O2, and 35%O2/65%CO2. Coal blends of coal with 10 and 20% of biomass were also studied under these atmospheres. The addition of 10 and 20% of steam was evaluated for the oxy-fuel combustion atmospheres with 21 and 30% of O2 in order to study the effect of the wet recirculation o...

  10. Comparisons between oxy-fuel combustion and IGCC technologies in China coal- energy industry

    OpenAIRE

    Zhao, Xue; Clemente Jul, María del Carmen

    2010-01-01

    A comparison between oxy-fuel combustion plants and IGCC plants has been carried out. Oxy-fuel combustion performs better for the retrofit of exist pulverized coal plants after the evaluation of efficiency, retrofit cost and O&M cost. China is currently and will depending on coal for its energy for a long time. Plenty of PC plants are used in existing power plants due to its lower coal consumption. One way to reduce CO2 emission with CCS is to equip existing power plants with appliance...

  11. Emission characteristics and combustion instabilities in an oxy-fuel swirl-stabilized combustor

    Institute of Scientific and Technical Information of China (English)

    Guo-neng LI; Hao ZHOU; Ke-fa CEN

    2008-01-01

    This paper presents an experimental study on the emission characteristics and combustion instabilities of oxy-fuel combustions in a swirl-stabilized combustor.Different oxygen concentrations(Xoxy=25%-45%,where Xoxy is oxygen concentra-tion by volume),equivalence ratios(=0.75~1.15)and combustion powers(CP=1.08~2.02kW)were investigated in the oxy-fuel (CH4/CO2/O2)combustions,and reference cases(Xoxy=25%~35%,Cha/N2/O2 flames)were covered.The results show that the oxygen concentration in the oxidant stream significantly affects the combustion delay in the oxy-fuel flames,and the equivalence ratio has a slight effect,whereas the combustion power shows no impact.The temperature levels of the oxy-fuel flames inside the combustion chamber are much higher(up to 38.7%)than those of the reference cases.Carbon monoxide was vastly producedwhen Xoxy>35% or >0.95 in the oxy-fuel flames,while no nitric oxide was found in the exhaust gases because no N2 participates in the combustion process.The combustion instability of the oxy-fuel combustion is very different from those of the reference cases with similar oxygen content.Oxy-fuel combustions excite strong oscillations in all cases studied Xoxy=25%~45%.However,no pressure fluctuations were detected in the reference cases when Xoxy>28.6% accomplished by heavily sooting flames which were not found in the oxy-fuel combustions.Spectrum analysis shows that the frequency of dynamic pressure oscillations exhibits randomness in the range of 50~250 Hz,therefore resulting in a very small resultant amplitude.Temporal oscillations are very strong with amplitudes larger than 200 Pa,even short time fast Fourier transform(FFT)analysis(0.08 s)shows that the pressure amplitude can be larger than 40 Pa.

  12. OxyR Activation in Porphyromonas gingivalis in Response to a Hemin-Limited Environment

    OpenAIRE

    Xie, Hua; Zheng, Cunge

    2012-01-01

    Porphyromonas gingivalis is a Gram-negative obligately anaerobic bacterium associated with several forms of periodontal disease, most closely with chronic periodontitis. Previous studies demonstrated that OxyR plays an important role in the aerotolerance of P. gingivalis by upregulating the expression of oxidative-stress genes. Increases in oxygen tension and in H2O2 both induce activation of OxyR. It is also known that P. gingivalis requires hemin as an iron source for its growth. In this st...

  13. Task 2: Materials for Advanced Boiler and Oxy-combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Holcolm, Gordon R.; McGhee, Barry

    2009-05-01

    The PowerPoint presentation provides an overview of the tasks for the project: Characterize advanced boiler (oxy-fuel combustion, biomass co-fired) gas compositions and ash deposits; Generate critical data on the effects of environmental conditions; develop a unified test method with a view to future standardization; Generate critical data for coating systems for use in advanced boiler systems; Generate critical data for flue gas recycle piping materials for oxy-fuel systems; and, Compile materials performance data from laboratory and pilot plant exposures of candidate alloys for use in advanced boiler systems.

  14. Crystal structure of 2-meth-oxy-2-[(4-meth-oxy-phen-yl)sulfan-yl]-1-phenyl-ethanone.

    Science.gov (United States)

    Caracelli, Ignez; Olivato, Paulo R; Traesel, Henrique J; Valença, Jéssica; Rodrigues, Daniel N S; Tiekink, Edward R T

    2015-09-01

    In the title β-thio-carbonyl compound, C16H16O3S, the adjacent meth-oxy and carbonyl O atoms are synperiplanar [the O-C-C-O torsion angle is 19.8 (4)°] and are separated by 2.582 (3) Å. The dihedral angle between the rings is 40.11 (16)°, and the meth-oxy group is coplanar with the benzene ring to which it is connected [the C-C-O-C torsion angle is 179.1 (3)°]. The most notable feature of the crystal packing is the formation of methine and methyl C-H⋯O(carbon-yl) inter-actions that lead to a supra-molecular chain with a zigzag topology along the c axis. Chains pack with no specific inter-molecular inter-actions between them.

  15. The OxyR homologue in Tannerella forsythia regulates expression of oxidative stress responses and biofilm formation.

    Science.gov (United States)

    Honma, Kiyonobu; Mishima, Elina; Inagaki, Satoru; Sharma, Ashu

    2009-06-01

    Tannerella forsythia is an anaerobic periodontal pathogen that encounters constant oxidative stress in the human oral cavity due to exposure to air and reactive oxidative species from coexisting dental plaque bacteria as well as leukocytes. In this study, we sought to characterize a T. forsythia ORF with close similarity to bacterial oxidative stress response sensor protein OxyR. To analyse the role of this OxyR homologue, a gene deletion mutant was constructed and characterized. Aerotolerance, survival after hydrogen peroxide challenge and transcription levels of known bacterial antioxidant genes were then determined. Since an association between oxidative stress and biofilm formation has been observed in bacterial systems, we also investigated the role of the OxyR protein in biofilm development by T. forsythia. Our results showed that aerotolerance, sensitivity to peroxide challenge and the expression of oxidative stress response genes were significantly reduced in the mutant as compared with the wild-type strain. Moreover, the results of biofilm analyses showed that, as compared with the wild-type strain, the oxyR mutant showed significantly less autoaggregation and a reduced ability to form mixed biofilms with Fusobacterium nucleatum. In conclusion, a gene annotated in the T. forsythia genome as an oxyR homologue was characterized. Our studies showed that the oxyR homologue in T. forsythia constitutively activates antioxidant genes involved in resistance to peroxides as well as oxygen stress (aerotolerance). In addition, the oxyR deletion attenuates biofilm formation in T. forsythia.

  16. An OxiTop (R) protocol for screening plant material for its biochemical methane potential (BMP)

    NARCIS (Netherlands)

    Pabon Pereira, C.P.; Castanares, G.; Lier, van J.B.

    2012-01-01

    A protocol was developed for determining the biochemical methane potential (BMP) of plant material using the OxiTop (R) system. NaOH pellets for CO2 absorption and different pretreatment methods were tested for their influence in the BMP test. The use of NaOH pellets in the headspace of the bottle n

  17. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    Science.gov (United States)

    This paper/presentation is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practicall...

  18. Membrane-integrated oxy-fuel combustion of coal: Process design and simulation

    NARCIS (Netherlands)

    Chen, Wei; Ham, van der A.G.J.; Nijmeijer, A.; Winnubst, A.J.A.

    2015-01-01

    A membrane-integrated oxy-fuel combustion process is designed and simulated in UniSim Design®. The results of the simulation indicate that a net efficiency of 31.8% is obtained for a coal-fired power plant of 182 MWth (assuming only carbon in the coal), including the compression of CO2 to 100 bar. T

  19. Development of Cost Effective Oxy-Combustion Retrofitting for Coal-Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Hamid Farzan

    2010-12-31

    The overall objective of this project is to further develop the oxy-combustion technology for commercial retrofit in existing wall-fired and Cyclone boilers by 2012. To meet this goal, a research project was conducted that included pilot-scale testing and a full-scale engineering and economic analysis.

  20. Oxy-fuel combustion of pulverized fuels: Combustion fundamentals and modeling

    DEFF Research Database (Denmark)

    Yin, Chungen; Yan, Jinyue

    2016-01-01

    Oxy-fuel combustion of pulverized fuels (PF), as a promising technology for CO2 capture from power plants, has gained a lot of concerns and also advanced considerable research, development and demonstration in the last past years worldwide. The use of CO2 or the mixture of CO2 and H2O vapor as th...

  1. OH Diffusion in Silica Glass Preform During Jacketing Process by Oxy-Hydrogen Burner

    Institute of Scientific and Technical Information of China (English)

    B. H. Kim; S. R. Han; U. C. Paek; W.-T. Han; S. K. Oh

    2003-01-01

    Radial distribution of OH diffusion in silica glass preform during jacketing process using a oxy-hydrogen burner was investigated by FTIR spectroscopy. The OH peaks at the jacketing boundary and the surface of the preform were found to be due to diffusion of OH incorporated from the burner.

  2. Synthesis of aluminum oxy-hydroxide nanofibers from porous anodic alumina.

    Science.gov (United States)

    Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki

    2008-10-01

    A novel method for the synthesis of aluminum oxy-hydroxide nanofibers from a porous anodic oxide film of aluminum is demonstrated. In the present method, the porous anodic alumina not only acts as a template, but also serves as the starting material for the synthesis. The porous anodic alumina film is hydrothermally treated for pore-sealing, which forms aluminum oxy-hydroxide inside the pores of the oxide film as well as on the surface of the film. The hydrothermally sealed porous oxide film is immersed in the sodium citrate solution, which selectively etches the porous aluminum oxide from the film, leaving the oxy-hydroxide intact. The method is simple and gives highly uniform aluminum oxy-hydroxide nanofibers. Moreover, the diameter of the nanofibers can be controlled by controlling the pore size of the porous anodic alumina film, which depends on the anodizing conditions. Nanofibers with diameters of about 38-85 nm, having uniform shape and size, were successfully synthesized using the present method.

  3. In vitro metabolism of the anti-androgenic fungicide vinclozolin by rat liver microsomes

    Science.gov (United States)

    Vinclozolin (V) is a fungicide used in agricultural settings. V administered to rats is hydrolyzed to 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid (Ml) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, Ml and M2 have antiandrogenic properties by in...

  4. Recovery Act: Oxy-Combustion Techology Development for Industrial-Scale Boiler Applications

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

    Alstom Power Inc. (Alstom), under U.S. DOE/NETL Cooperative Agreement No. DE-NT0005290, is conducting a development program to generate detailed technical information needed for application of oxy-combustion technology. The program is designed to provide the necessary information and understanding for the next step of large-scale commercial demonstration of oxy combustion in tangentially fired boilers and to accelerate the commercialization of this technology. The main project objectives include: • Design and develop an innovative oxyfuel system for existing tangentially-fired boiler units that minimizes overall capital investment and operating costs. • Evaluate performance of oxyfuel tangentially fired boiler systems in pilot scale tests at Alstom’s 15 MWth tangentially fired Boiler Simulation Facility (BSF). • Address technical gaps for the design of oxyfuel commercial utility boilers by focused testing and improvement of engineering and simulation tools. • Develop the design, performance and costs for a demonstration scale oxyfuel boiler and auxiliary systems. • Develop the design and costs for both industrial and utility commercial scale reference oxyfuel boilers and auxiliary systems that are optimized for overall plant performance and cost. • Define key design considerations and develop general guidelines for application of results to utility and different industrial applications. The project was initiated in October 2008 and the scope extended in 2010 under an ARRA award. The project completion date was April 30, 2014. Central to the project is 15 MWth testing in the BSF, which provided in-depth understanding of oxy-combustion under boiler conditions, detailed data for improvement of design tools, and key information for application to commercial scale oxy-fired boiler design. Eight comprehensive 15 MWth oxy-fired test campaigns were performed with different coals, providing detailed data on combustion, emissions, and thermal behavior over a

  5. A Mechanistic Investigation of Nitrogen Evolution and Corrosion with Oxy-Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Dale Tree; Andrew Mackrory; Thomas Fletcher

    2008-12-31

    A premixed, staged, down-fired, pulverized coal reactor and a flat flame burner were used to study the evolution of nitrogen in coal contrasting differences in air and oxy-combustion. In the premixed reactor, the oxidizer was staged to produce a fuel rich zone followed by a burnout zone. The initial nominal fuel rich zone stoichiometric ratio (S.R.) of 0.85 selected produced higher NO reductions in the fuel rich region under oxy-combustion conditions. Air was found to be capable of similar NO reductions when the fuel rich zone was at a much lower S.R. of 0.65. At a S.R. of 0.85, oxy-combustion was measured to have higher CO, unburned hydrocarbons, HCN and NH{sub 3} in the fuel rich region than air at the same S.R. There was no measured difference in the initial formation of NO. The data suggest devolatilization and initial NO formation is similar for the two oxidizers when flame temperatures are the same, but the higher CO{sub 2} leads to higher concentrations of CO and nitrogen reducing intermediates at a given equivalence ratio which increases the ability of the gas phase to reduce NO. These results are supported by flat flame burner experiments which show devolatilization of nitrogen from the coal and char to be similar for air and oxy-flame conditions at a given temperature. A model of premixed combustion containing devolatilization, char oxidation and detailed kinetics captures most of the trends seen in the data. The model suggests CO is high in oxy-combustion because of dissociation of CO{sub 2}. The model also predicts a fraction (up to 20%, dependent on S.R.) of NO in air combustion can be formed via thermal processes with the source being nitrogen from the air while in oxy-combustion equilibrium drives a reduction in NO of similar magnitude. The data confirm oxy-combustion is a superior oxidizer to air for NO control because NO reduction can be achieved at higher S.R. producing better char burnout in addition to NO from recirculated flue gas being reduced

  6. Adsorption characteristics of U(VI) on Fe(III)Cr(III) (oxy)hydroxides synthesized at different temperatures.

    Science.gov (United States)

    Ahn, Hyangsig; Jo, Ho Young; Lee, Young Jae; Kim, Geon-Young

    2016-07-01

    In this study, the adsorption behavior of U(VI) on (oxy)hydroxides synthesized at different temperatures (25 and 75 °C) was investigated. Four (oxy)hydroxides were synthesized by drying slurries of Fe(III) and Fe(III)Cr(III) (oxy)hydroxide in a vacuum desiccator (25 °C) or in an oven (75 °C). Batch adsorption tests were conducted using the (oxy)hydroxides thus synthesized and groundwater containing uranium ions. In general, the U(VI) removal fraction significantly increased with increasing pH from 3 to 5, remained constant with increasing pH from 5 to 9, and decreased at pH greater than 9, regardless of the type of (oxy)hydroxides and solid-to-liquid ratio. The effect of pH on the U(VI) removal fraction was more significant at a low solid-to-liquid ratio. The oven-dried Fe(III) (oxy)hydroxide exhibited a U(VI) removal fraction lower than that of the vacuum-dried one, whereas the oven-dried Fe(III)Cr(III) (oxy)hydroxide exhibited a U(VI) removal fraction higher than that exhibited by the vacuum-dried one. X-ray photoelectron spectroscopy (XPS) analysis results indicated that the difference in the U(VI) removal fraction is attributed to the dissolution and precipitation of the Fe(III) (oxy)hydroxide during oven drying and dehydration of the Fe(III)Cr(III) (oxy)hydroxide during oven drying.

  7. Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bradley [Univ. of Utah, Salt Lake City, UT (United States); Davis, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Senior, Constance [Univ. of Utah, Salt Lake City, UT (United States); Shim, Hong Shim [Univ. of Utah, Salt Lake City, UT (United States); Otten, Brydger Van [Univ. of Utah, Salt Lake City, UT (United States); Fry, Andrew [Univ. of Utah, Salt Lake City, UT (United States); Wendt, Jost [Univ. of Utah, Salt Lake City, UT (United States); Eddings, Eric [Univ. of Utah, Salt Lake City, UT (United States); Paschedag, Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shaddix, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cox, William [Brigham Young Univ., Provo, UT (United States); Tree, Dale [Brigham Young Univ., Provo, UT (United States)

    2013-09-30

    Reaction Engineering International (REI) managed a team of experts from University of Utah, Siemens Energy, Praxair, Vattenfall AB, Sandia National Laboratories, Brigham Young University (BYU) and Corrosion Management Ltd. to perform multi-scale experiments, coupled with mechanism development, process modeling and CFD modeling, for both applied and fundamental investigations. The primary objective of this program was to acquire data and develop tools to characterize and predict impacts of CO{sub 2} flue gas recycle and burner feed design on flame characteristics (burnout, NO{sub x}, SO{sub x}, mercury and fine particle emissions, heat transfer) and operational concerns (fouling, slagging and corrosion) inherent in the retrofit of existing coal-fired boilers for oxy-coal combustion. Experimental work was conducted at Sandia National Laboratories’ Entrained Flow Reactor, the University of Utah Industrial Combustion Research Facility, and Brigham Young University. Process modeling and computational fluid dynamics (CFD) modeling was performed at REI. Successful completion of the project objectives resulted in the following key deliverables: 1) Multi-scale test data from 0.1 kW bench-scale, 100 kW and 200 kW laboratory-scale, and 1 MW semi-industrial scale combustors that describe differences in flame characteristics, fouling, slagging and corrosion for coal combustion under air-firing and oxygen-firing conditions, including sensitivity to oxy-burner design and flue gas recycle composition. 2) Validated mechanisms developed from test data that describe fouling, slagging, waterwall corrosion, heat transfer, char burnout and sooting under coal oxy-combustion conditions. The mechanisms were presented in a form suitable for inclusion in CFD models or process models. 3) Principles to guide design of pilot-scale and full-scale coal oxy-firing systems and flue gas recycle configurations, such that boiler operational impacts from oxy-combustion retrofits are minimized. 4

  8. Numerical Simulation of Oxy-coal Combustion for a Swirl Burner with EDC Model

    Institute of Scientific and Technical Information of China (English)

    崔凯; 刘冰; 吴玉新; 杨海瑞; 吕俊复; 张海

    2014-01-01

    The characteristics of oxy-coal combustion for a swirl burner with a specially designed preheating chamber are studied numerically. In order to increase the accuracy in the prediction of flame temperature and igni-tion position, eddy dissipation concept (EDC) model with a skeletal chemical reaction mechanism was adopted to describe the combustion of volatile matter. Simulation was conducted under six oxidant stream conditions with dif-ferent O2/N2/CO2 molar ratios:21/79/0, 30/70/0, 50/50/0, 21/0/79, 30/0/70 and 50/0/50. Results showed that O2 en-richment in the primary oxidant stream is in favor of combustion stabilization, acceleration of ignition and increase of maximum flame temperature, while the full substitution of N2 by CO2 in the oxidant stream delays ignition and decreases the maximum flame temperature. However, the overall flow field and flame shapes in these cases are very similar at the same flow rate of the primary oxidant stream. Combustion characteristics of the air-coal is similar to that of the oxy-coal with 30%O2 and 70%CO2 in the oxidant stream, indicating that the rear condition is suitable for retrofitting an air-coal fired boiler to an oxy-coal one. The swirl burner with a specially designed preheating chamber can increase flame temperature, accelerate ignition and enhance burning intensity of pulverized coal under oxy-coal combustion. Also, qualitative experimental validation indicated the burner can reduce the overall NOx emission under certain O2 enrichment and oxy-coal combustion conditions against the air-coal combustion.

  9. rac-2-{[1-(1-Adamant-yl)eth-yl]imino-meth-yl}-5-meth-oxy-phenol.

    Science.gov (United States)

    Jin, Xu-Dong; Wang, Hai-Bo; Jin, Yue-Hong

    2011-09-01

    A novel Schiff base compound, C(20)H(27)NO(2), was obtained by a condensation of rimantadine and 2-hy-droxy-4-meth-oxy-benzaldehyde. An intra-molecular O-H⋯N hydrogen bond supports the phenol-imine tautomeric form. The adamantane and imino-methyl-4-meth-oxy-phenol units are arranged in a folded conformation [C-N-C-C torsion angle = 110.9 (3)°]. In the crystal, highly hydro-phobic adamantane moieties are inserted between the imino-methyl-4-meth-oxy-phenol units in a sandwich-like arrangement along the c axis.

  10. Novel Supercritical Carbon Dioxide Power Cycle Utilizing Pressured Oxy-combustion in Conjunction with Cryogenic Compression

    Energy Technology Data Exchange (ETDEWEB)

    Brun, Klaus; McClung, Aaron; Davis, John

    2014-03-31

    The team of Southwest Research Institute® (SwRI) and Thar Energy LLC (Thar) applied technology engineering and economic analysis to evaluate two advanced oxy-combustion power cycles, the Cryogenic Pressurized Oxy-combustion Cycle (CPOC), and the Supercritical Oxy-combustion Cycle. This assessment evaluated the performance and economic cost of the two proposed cycles with carbon capture, and included a technology gap analysis of the proposed technologies to determine the technology readiness level of the cycle and the cycle components. The results of the engineering and economic analysis and the technology gap analysis were used to identify the next steps along the technology development roadmap for the selected cycle. The project objectives, as outlined in the FOA, were 90% CO{sub 2} removal at no more than a 35% increase in cost of electricity (COE) as compared to a Supercritical Pulverized Coal Plant without CO{sub 2} capture. The supercritical oxy-combustion power cycle with 99% carbon capture achieves a COE of $121/MWe. This revised COE represents a 21% reduction in cost as compared to supercritical steam with 90% carbon capture ($137/MWe). However, this represents a 49% increase in the COE over supercritical steam without carbon capture ($80.95/MWe), exceeding the 35% target. The supercritical oxy-combustion cycle with 99% carbon capture achieved a 37.9% HHV plant efficiency (39.3% LHV plant efficiency), when coupling a supercritical oxy-combustion thermal loop to an indirect supercritical CO{sub 2} (sCO{sub 2}) power block. In this configuration, the power block achieved 48% thermal efficiency for turbine inlet conditions of 650°C and 290 atm. Power block efficiencies near 60% are feasible with higher turbine inlet temperatures, however a design tradeoff to limit firing temperature to 650°C was made in order to use austenitic stainless steels for the high temperature pressure vessels and piping and to minimize the need for advanced turbomachinery features

  11. Advanced diagnostics in oxy-fuel combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Brix, J.; Clausen, Soennik; Degn Jensen, A. (Technical Univ. of Denmark. CHEC Research Centre, Kgs. Lyngby (Denmark)); Boeg Toftegaard, M. (DONG Energy Power, Hvidovre (Denmark))

    2012-07-01

    This report sums up the findings in PSO-project 010069, ''Advanced Diagnostics in Oxy-Fuel Combustion Processes''. Three areas of optic diagnostics are covered in this work: - FTIR measurements in a 30 kW swirl burner. - IR measurements in a 30 kW swirl burner. - IR measurements in a laboratory scale fixed bed reactor. The results obtained in the swirl burner have proved the FTIR method as a valuable technique for gas phase temperature measurements. When its efficacy is evaluated against traditional thermocouple measurements, two cases, with and without probe beam stop, must however be treated separately. When the FTIR probe is operated with the purpose of gas phase concentration measurements the probe needs to operate with a beam stop mounted in front of it. With this beam stop in place it was shown that the measured gas phase temperature was affected by cooling, induced by the cooled beam stop. Hence, for a more accurate determination of gas phase temperatures the probe needed to operate without the beam stop. When this was the case, the FTIR probe showed superior to traditional temperature measurements using a thermocouple as it could measure the fast temperature fluctuations. With the beam stop in place the efficacy of the FTIR probe for gas temperature determination was comparable to the use of a traditional thermocouple. The evaluation of the FTIR technique regarding estimation of gas phase concentrations of H{sub 2}O, CO{sub 2} and CO showed that the method is reliable though it cannot be stated as particularly accurate. The accuracy of the method is dependent on the similarity of the reference emission spectra of the gases with those obtained in the experiments, as the transmittance intensity is not a linear function of concentration. The length of the optical path also affects the steadiness of the measurements. The length of the optical path is difficult to adjust on the small scales that are the focus of this work. However

  12. Limited impairments of associative learning in a mouse model of accelerated senescence.

    Science.gov (United States)

    Yang, Yi; Wu, Guang-yan; Li, Xuan; Huang, He; Hu, Bo; Yao, Juan; Wu, Bing; Sui, Jian-feng

    2013-11-15

    Research concerning impairment of associative learning during aging remains limited. The senescence-accelerated mice (SAM) prone/8 (P8) has been proposed as a useful model for the study of aging, and SAM resistant/1(SAMR1) is its control as a normal aging strain. Classical eyeblink conditioning has long been served as a model of associative learning. In order to explore the effects of aging on associative learning in SAM, the present study successively tested three paradigms of eyeblink conditioning in SAMP8 and SAMR1: classical single cue trace eyeblink conditioning (TEC), discriminative trace eyeblink conditioning and reversal learning of TEC. Behavioral performance indicated that SAMP8 could acquire limited single-cue trace eyeblink conditioning task and two-tone discrimination trace eyeblink conditioning with a relative lower acquisition rate compared to SAMR1. Both SAMP8 and SAMR1 failed to acquire reversal learning of discriminative TEC, and SAMP8' startle reflex to tone CS was lower than SAMR1. These results indicated that the impairments of aging on associative learning were incomplete in SAMP8.

  13. Aging is associated with decreased maximal life span and accelerated senescence of bone marrow stromal cells

    DEFF Research Database (Denmark)

    Dokkedahl, Karin Stenderup; Justesen, Jeannette; Clausen, Christian

    2003-01-01

    donors were able to form similar amounts of mineralized matrix in vitro and of normal lamellar bone in vivo. In adipogenic medium similar numbers of adipocytes formed in cultures of young and old donors. In conclusion, aging is associated with decreased proliferative capacity of osteoprogenitor cells......Age-related decrease in bone formation is well described. However, the cellular causes are not known. Thus, we have established cultures of bone marrow stromal cells (MSC) from young (aged 18-29 years, n = 6) and old (aged 68-81 years, n = 5) donors. MSC were serially passaged until reaching......, suggesting that decreased osteoblastic cell number, and not function, leads to age-related decrease in bone formation....

  14. Crystal structure of 2-[chloro-(4-meth-oxy-phen-yl)meth-yl]-2-(4-meth-oxy-phen-yl)-5,5-di-methyl-cyclo-hexane-1,3-dione.

    Science.gov (United States)

    Chelli, Saloua; Troshin, Konstantin; Lakhdar, Sami; Mayr, Herbert; Mayer, Peter

    2016-03-01

    In the title compound, C23H25ClO4, the cyclo-hexane ring adopts a chair conformation with the 4-meth-oxy-phenyl substituent in an axial position and the chloro-(4-meth-oxy-phen-yl)methyl substituent in an equatorial position. The packing features inversion dimers formed by pairs of C-H⋯O contacts and strands along [100] and [010] established by further C-H⋯O and C-H⋯Cl contacts, respectively.

  15. Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Bradley Adams; Andrew Fry; Constance Senior; Hong Shim; Huafeng Wang; Jost Wendt; Christopher Shaddix

    2009-06-30

    This report summarizes Year 1 results of a research program designed to use multi-scale experimental studies and fundamental theoretical models to characterize and predict the impacts of retrofit of existing coal-fired utility boilers for oxy-combustion. Through the course of Year 1 activities, great progress was made toward understanding the issues associated with oxy-combustion retrofit of coal-fired boilers. All four Year 1 milestones and objectives have been, or will be, completed on schedule and within budget. Progress in the four milestone areas may be summarized as follows: • University of Utah has performed size segregated ash composition measurements in the Oxy-Fuel Combustor (OFC). These experiments indicate that oxy-combustion retrofit may impact ash aerosol mineral matter composition. Both flame temperature and flue gas composition have been observed to influence the concentration of calcium, magnesium and iron in the fine particulate. This could in turn impact boiler fouling and slagging. • Sandia National Labs has shown that char oxidation rate is dependent on particle size (for sizes between 60 and 100 microns) by performing fundamental simulations of reacting char particles. These predictions will be verified by making time-resolved optical measurements of char particle temperature, velocity and size in bench-scale experiments before the end of Year 1. • REI and Siemens have completed the design of an oxy-research burner that will be mounted on University of Utah’s pilot-scale furnace, the L1500. This burner will accommodate a wide range of O2, FGR and mixing strategies under conditions relevant for utility boiler operation. Through CFD modeling of the different burner designs, it was determined that the key factor influencing flame stabilization location is particle heat-up rate. The new oxy-research burner and associated equipment is scheduled for delivery before the end of Year 1. • REI has completed a literature survey of slagging and

  16. 2,2,6,6-Tetra-bromo-3,4,4,5-tetra-meth-oxy-cyclo-hexa-none.

    Science.gov (United States)

    Faizi, Md Serajul Haque; Mashrai, Ashraf; Shahid, M

    2014-07-01

    In the title compound, C10H14Br4O5, synthesized from the meth-oxy Schiff base N-(pyridin-2-ylmeth-yl)meth-oxy-aniline and mol-ecular bromine, the cyclo-hexa-none ring has a chair conformation with one of the four meth-oxy groups equatorially orientated with respect to the carbonyl group and the others axially orientated. The C-Br bond lengthsvary from 1.942 (4) to1.964 (4) Å. In the crystal, weak C-H⋯Ocarbon-yl hydrogen-bonding inter-actions generate chains extending along the b-axis direction. Also present in the structure are two short inter-molecular Br⋯Ometh-oxy inter-actions [3.020 (3) and 3.073 (4) Å].

  17. 2-(4-Meth-oxy-phen-yl)-1-pentyl-4,5-di-phenyl-1H-imidazole.

    Science.gov (United States)

    Simpson, Jim; Mohamed, Shaaban K; Marzouk, Adel A; Talybov, Avtandil H; Abdelhamid, Antar A

    2013-01-01

    The title compound, C27H28N2O, is a lophine (2,4,5-triphenyl-1H-imidazole) derivative with an n-pentyl chain on the amine N atom and a 4-meth-oxy substituent on the benzene ring. The two phenyl and meth-oxy-benzene rings are inclined to the imidazole ring at angles of 25.32 (7), 76.79 (5) and 35.42 (7)°, respectively, while the meth-oxy substituent lies close to the plane of its benzene ring, with a maximum deviation of 0.126 (3) Å for the meth-oxy C atom. In the crystal, inversion dimers linked by pairs of C-H⋯O hydrogen bonds generate R2(2)(22) loops. These dimers are stacked along the a-axis direction.

  18. Tantalum (oxy)nitrides nanotube arrays for the degradation of atrazine in vis-Fenton-like process

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingxun, E-mail: yxdu@niglas.ac.cn [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China); Zhao, Lu [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China); Chang, Yuguang [School of Biochemical and Environmental Engineering, Nanjing Xiaozhuang Univeristy, Nanjing 211171 (China); Su, Yaling [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China)

    2012-07-30

    Highlights: Black-Right-Pointing-Pointer Tantala nanotubes on a Ta foil were formed by anodization in a NH{sub 4}F-containing electrolyte. Black-Right-Pointing-Pointer Tantalum (oxy)nitrides nanotubes were active for Fe{sup 3+} reduction under visible light. Black-Right-Pointing-Pointer Atrazine degradation by {center_dot}OH was accelerated with tantalum (oxy)nitrides nanotubes. Black-Right-Pointing-Pointer Tantalum (oxy)nitrides nanotubes display stable performance for atrazine degradation. - Abstract: In order to overcome the limitation of the application of nanoparticles, tantalum (oxy)nitrides nanotube arrays on a Ta foil were synthesized and introduced in vis (visible light)-Fenton-like system to enhance the degradation of atrazine. At first, the anodization of tantalum foil in a mild electrolyte solution containing ethylene glycol and water (v:v = 2:1) plus 0.5 wt.% NH{sub 4}F produced tantala nanotubes with an average diameter of 30 nm and a length of approximately 1 {mu}m. Then the nitridation of tantala nanotube arrays resulted in the replacement of N atoms to O atoms to form tantalum (oxy)nitrides (TaON and Ta{sub 3}N{sub 5}), as testified by XRD and XPS analyses. The synthesized tantalum (oxy)nitrides nanotubes absorb well in the visible region up to 600 nm. Under visible light, tantalum (oxy)nitrides nanotube arrays were catalytically active for Fe{sup 3+} reduction. With tantalum (oxy)nitrides nanotube arrays, the degradation of atrazine and the formation of the intermediates in vis/Fe{sup 3+}/H{sub 2}O{sub 2} system were significantly accelerated. This was explained by the higher concentration of Fe{sup 2+} and thus the faster decomposition of H{sub 2}O{sub 2} with tantalum (oxy)nitrides nanotubes. In addition, tantalum (oxy)nitrides nanotubes exhibited stable performance during atrazine degradation for three runs. The good performance and stability of the tantalum (oxy)nitrides nanotubes film with the convenient separation, suggest that this film is

  19. Tantalum (oxy)nitrides nanotube arrays for the degradation of atrazine in vis-Fenton-like process.

    Science.gov (United States)

    Du, Yingxun; Zhao, Lu; Chang, Yuguang; Su, Yaling

    2012-07-30

    In order to overcome the limitation of the application of nanoparticles, tantalum (oxy)nitrides nanotube arrays on a Ta foil were synthesized and introduced in vis (visible light)-Fenton-like system to enhance the degradation of atrazine. At first, the anodization of tantalum foil in a mild electrolyte solution containing ethylene glycol and water (v:v=2:1) plus 0.5wt.% NH(4)F produced tantala nanotubes with an average diameter of 30nm and a length of approximately 1μm. Then the nitridation of tantala nanotube arrays resulted in the replacement of N atoms to O atoms to form tantalum (oxy)nitrides (TaON and Ta(3)N(5)), as testified by XRD and XPS analyses. The synthesized tantalum (oxy)nitrides nanotubes absorb well in the visible region up to 600nm. Under visible light, tantalum (oxy)nitrides nanotube arrays were catalytically active for Fe(3+) reduction. With tantalum (oxy)nitrides nanotube arrays, the degradation of atrazine and the formation of the intermediates in vis/Fe(3+)/H(2)O(2) system were significantly accelerated. This was explained by the higher concentration of Fe(2+) and thus the faster decomposition of H(2)O(2) with tantalum (oxy)nitrides nanotubes. In addition, tantalum (oxy)nitrides nanotubes exhibited stable performance during atrazine degradation for three runs. The good performance and stability of the tantalum (oxy)nitrides nanotubes film with the convenient separation, suggest that this film is a promising catalyst for vis-Fenton-like degradation.

  20. Coal-Based Oxy-Fuel System Evaluation and Combustor Development; Oxy-Fuel Turbomachinery Development for Energy Intensive Industrial Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hollis, Rebecca

    2013-03-31

    Clean Energy Systems, Inc. (CES) partnered with the U.S. Department of Energy’s National Energy Technology Laboratory in 2005 to study and develop a competing technology for use in future fossil-fueled power generation facilities that could operate with near zero emissions. CES’s background in oxy-fuel (O-F) rocket technology lead to the award of Cooperative Agreement DE-FC26-05NT42645, “Coal-Based Oxy-Fuel System Evaluation and Combustor Development,” where CES was to first evaluate the potential of these O-F power cycles, then develop the detailed design of a commercial-scale O-F combustor for use in these clean burning fossil-fueled plants. Throughout the studies, CES found that in order to operate at competitive cycle efficiencies a high-temperature intermediate pressure turbine was required. This led to an extension of the Agreement for, “Oxy-Fuel Turbomachinery Development for Energy Intensive Industrial Applications” where CES was to also develop an intermediate-pressure O-F turbine (OFT) that could be deployed in O-F industrial plants that capture and sequester >99% of produced CO2, at competitive cycle efficiencies using diverse fuels. The following report details CES’ activities from October 2005 through March 2013, to evaluate O-F power cycles, develop and validate detailed designs of O-F combustors (main and reheat), and to design, manufacture, and test a commercial-scale OFT, under the three-phase Cooperative Agreement.

  1. Structural assignment of 6-oxy purine derivatives through computational modeling, synthesis, X-ray diffraction, and spectroscopic analysis.

    Science.gov (United States)

    Zhao, Xinyun; Chen, Xi; Yang, Guang-Fu; Zhan, Chang-Guo

    2010-05-27

    6-Oxy purine derivatives have been considered as potential therapeutic agents in various drug discovery efforts reported in the literature. However, the structural assignment of this important class of compounds has been controversial concerning the specific position of a hydrogen atom in the structure. To theoretically determine the most favorable type of tautomeric form of 6-oxy purine derivatives, we have carried out first-principles electronic structure calculations on the possible tautomeric forms (A, B, and C) and their relative stability of four representative 6-oxy purine derivatives (compounds 1-4). The computational results in both the gas phase and aqueous solution clearly reveal that the most favorable type of tautomeric form of these compounds is A, in which a hydrogen atom bonds with the N1 atom on the purine ring. To examine the computational results, one of the 6-oxy purine derivatives (i.e., compound 4) has been synthesized and its structure has been characterized by X-ray diffraction and spectroscopic analysis. All of the obtained computational and experimental data are consistent with the conclusion that the 6-oxy purine derivative exists in tautomer A. The conclusive structural assignment reported here is expected to be valuable for future computational studies on 6-oxy purine derivative binding with proteins and for computational drug design involving this type of compounds.

  2. Near-Zero Emissions Oxy-Combustion Flue Gas Purification

    Energy Technology Data Exchange (ETDEWEB)

    Minish Shah; Nich Degenstein; Monica Zanfir; Rahul Solunke; Ravi Kumar; Jennifer Bugayong; Ken Burgers

    2012-06-30

    The objectives of this project were to carry out an experimental program to enable development and design of near zero emissions (NZE) CO{sub 2} processing unit (CPU) for oxy-combustion plants burning high and low sulfur coals and to perform commercial viability assessment. The NZE CPU was proposed to produce high purity CO{sub 2} from the oxycombustion flue gas, to achieve > 95% CO{sub 2} capture rate and to achieve near zero atmospheric emissions of criteria pollutants. Two SOx/NOx removal technologies were proposed depending on the SOx levels in the flue gas. The activated carbon process was proposed for power plants burning low sulfur coal and the sulfuric acid process was proposed for power plants burning high sulfur coal. For plants burning high sulfur coal, the sulfuric acid process would convert SOx and NOx in to commercial grade sulfuric and nitric acid by-products, thus reducing operating costs associated with SOx/NOx removal. For plants burning low sulfur coal, investment in separate FGD and SCR equipment for producing high purity CO{sub 2} would not be needed. To achieve high CO{sub 2} capture rates, a hybrid process that combines cold box and VPSA (vacuum pressure swing adsorption) was proposed. In the proposed hybrid process, up to 90% of CO{sub 2} in the cold box vent stream would be recovered by CO{sub 2} VPSA and then it would be recycled and mixed with the flue gas stream upstream of the compressor. The overall recovery from the process will be > 95%. The activated carbon process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx, thus exceeding the performance targets of >99% and >95%, respectively. The process was also found to be suitable for power plants burning both low and high sulfur coals. Sulfuric acid process did not meet the performance expectations. Although it could achieve high SOx (>99%) and NOx (>90%) removal efficiencies, it could not produce by

  3. Near-Zero Emissions Oxy-Combustion Flue Gas Purification

    Energy Technology Data Exchange (ETDEWEB)

    Minish Shah; Nich Degenstein; Monica Zanfir; Rahul Solunke; Ravi Kumar; Jennifer Bugayong; Ken Burgers

    2012-06-30

    The objectives of this project were to carry out an experimental program to enable development and design of near zero emissions (NZE) CO{sub 2} processing unit (CPU) for oxy-combustion plants burning high and low sulfur coals and to perform commercial viability assessment. The NZE CPU was proposed to produce high purity CO{sub 2} from the oxycombustion flue gas, to achieve > 95% CO{sub 2} capture rate and to achieve near zero atmospheric emissions of criteria pollutants. Two SOx/NOx removal technologies were proposed depending on the SOx levels in the flue gas. The activated carbon process was proposed for power plants burning low sulfur coal and the sulfuric acid process was proposed for power plants burning high sulfur coal. For plants burning high sulfur coal, the sulfuric acid process would convert SOx and NOx in to commercial grade sulfuric and nitric acid by-products, thus reducing operating costs associated with SOx/NOx removal. For plants burning low sulfur coal, investment in separate FGD and SCR equipment for producing high purity CO{sub 2} would not be needed. To achieve high CO{sub 2} capture rates, a hybrid process that combines cold box and VPSA (vacuum pressure swing adsorption) was proposed. In the proposed hybrid process, up to 90% of CO{sub 2} in the cold box vent stream would be recovered by CO{sub 2} VPSA and then it would be recycled and mixed with the flue gas stream upstream of the compressor. The overall recovery from the process will be > 95%. The activated carbon process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx, thus exceeding the performance targets of >99% and >95%, respectively. The process was also found to be suitable for power plants burning both low and high sulfur coals. Sulfuric acid process did not meet the performance expectations. Although it could achieve high SOx (>99%) and NOx (>90%) removal efficiencies, it could not produce by

  4. An OxiTop(®) protocol for screening plant material for its biochemical methane potential (BMP).

    Science.gov (United States)

    Pabón Pereira, C P; Castañares, G; van Lier, J B

    2012-01-01

    A protocol was developed for determining the biochemical methane potential (BMP) of plant material using the OxiTop(®) system. NaOH pellets for CO(2) absorption and different pretreatment methods were tested for their influence in the BMP test. The use of NaOH pellets in the headspace of the bottle negatively affected the stability of the test increasing the pH and inhibiting methanization. Sample comminution increased the biodegradability of plant samples. Our results clearly indicate the importance of test conditions during the assessment of anaerobic biodegradability of plant material, considering BMP differences as high as 44% were found. Guidelines and recommendations are given for screening plant material suitable for anaerobic digestion using the OxiTop(®) system.

  5. Tetranuclear zinc(II-oxy (benzothiazole-2-thiolate aggregate and copper(I phenylthiolate aggregate

    Directory of Open Access Journals (Sweden)

    Abir Goswami

    2015-12-01

    Full Text Available A tetranuclear zinc-oxy (benzothiazole-2-thiolate aggregate whose structure has a C3-axis passing through ZnO unit relating three other zinc ions and a tetranuclear copper(I phenylthiolate aggregate having each thiphenolate ligand bridging three copper ions are reported. These aggregates were prepared by hydrothermal reactions of 2,2′-dithiobis-(benzothiazole with zinc nitrate or copper(I iodide, respectively. The reaction of zinc nitrate passed through in situ abstraction of a oxy ligand from moisture to form a Zn4O core holding six 2-benzothiazolethiolate ligands, and during the formation of the aggregate, cleavage of S–S bond of 2,2′-dithiobis-(benzothiazole took place. Whereas, an aggregate formed by self-assembling of copper(I phenylthiolate was formed after extensive degradation of 2,2′-dithiobis-(benzothiazole during solvothermal reaction.

  6. Analysis of the Transition Time From Air to Oxy-Combustion

    Directory of Open Access Journals (Sweden)

    Lasek Janusz

    2015-03-01

    Full Text Available In this paper some issues of the transition process from air- to oxy-combustion were investigated. Advantages of flexible combustion were described. Flexible combustion tests carried out at four European plants and five plants outside Europe of different scales of process and test parameters were presented. An analysis of the transition time from air to oxy-combustion of different laboratory and pilot scale processes was carried out. The “first-order + dead time” approach was used as a model to describe transition process. Transitional periods between combustion modes and characteristic parameters of the process were determined. The transition time depends not only on the facility’s capacity but also it is impacted by specific operational parameters.

  7. Characteristics modeling for supercritical circulating fluidized bed boiler working in oxy-combustion technology

    Science.gov (United States)

    Balicki, Adrian; Bartela, Łukasz

    2014-06-01

    Among the technologies which allow to reduce greenhouse gas emission, mainly carbon dioxide, special attention deserves the idea of `zeroemission' technology based on boilers working in oxy-combustion technology. In the paper the results of analyses of the influence of changing two quantities, namely oxygen share in oxidant produced in the air separation unit, and oxygen share in oxidant supplied to the furnace chamber on the selected characteristics of a steam boiler including the degree of exhaust gas recirculation, boiler efficiency and adiabatic flame temperature, was examined. Due to the possibility of the integration of boiler model with carbon dioxide capture, separation and storage installation, the subject of the analysis was also to determine composition of the flue gas at the outlet of a moisture condensation installation. Required calculations were made using a model of a supercritical circulating fluidized bed boiler working in oxy-combustion technology, which was built in a commercial software and in-house codes.

  8. Simultaneous carbonation and sulfation of CaO in Oxy-Fuel CFB combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C. [School of Energy and Power Engineering, North China Electric Power University, Baoding City, Hebei Province (China); Jia, L.; Tan, Y. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A 1M1 (Canada)

    2011-10-15

    For anthracites and petroleum cokes, the typical combustion temperature in a circulating fluidized bed (CFB) is > 900 C. At CO{sub 2} concentrations of 80-85 % (typical of oxy-fuel CFBC conditions), limestone still calcines. When the ash which includes unreacted CaO cools to the calcination temperature, carbonation of fly ash deposited on cool surfaces may occur. At the same time, indirect and direct sulfation of limestone also will occur, possibly leading to more deposition. In this study, CaO was carbonated and sulfated simultaneously in a thermogravimetric analyzer (TGA) under conditions expected in an oxy-fuel CFBC. It was found that temperature, and concentrations of CO{sub 2}, SO{sub 2}, and especially H{sub 2}O are important factors in determining the carbonation/sulfation reactions of CaO. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Study of Reaction of Curium Oxy-Compound Formation in Molten Chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, A.G.; Mayorshin, A.A.; Bychkov, A.V. [Dimitrovgrad-10, Ulyanovsk region, 433510 (Russian Federation)

    2008-07-01

    The method of potentiometric titration using oxygen sensors with solid electrolyte membrane was applied for the study of the interaction of curium cations with oxygen anions in the molten alkali metal chlorides in the temperature range of 450-850 C degrees depending on oxy-acidity of the environment. Assumptions were made concerning ion and phase composition of the obtained high-temperature compounds and chemical reactions taking place in the melts. This scheme assumes that as the basicity of the melt increases, initially the formation of soluble curium oxychlorides takes place in the melt (presumably CmO{sup -}) that is followed by formation of solid CmOCl and finally sesquioxide Cm{sub 2}O{sub 3}. Basic thermodynamic values were calculated for the resultant curium oxy-compounds.

  10. 5-((3-Amidobenzyl)oxy)nicotinamides as Sirtuin 2 Inhibitors.

    Science.gov (United States)

    Ai, Teng; Wilson, Daniel J; More, Swati S; Xie, Jiashu; Chen, Liqiang

    2016-04-14

    Derived from our previously reported human sirtuin 2 (SIRT2) inhibitors that were based on a 5-aminonaphthalen-1-yloxy nicotinamide core structure, 5-((3-amidobenzyl)oxy)nicotinamides offered excellent activity against SIRT2 and high isozyme selectivity over SIRT1 and SIRT3. Selected compounds also exhibited generally favorable in vitro absorption, distribution, metabolism, and excretion properties. Kinetic studies revealed that a representative SIRT2 inhibitor acted competitively against both NAD(+) and the peptide substrate, an inhibitory modality that was supported by our computational study. More importantly, two selected compounds exhibited significant protection against α-synuclein aggregation-induced cytotoxicity in SH-SY5Y cells. Therefore, 5-((3-amidobenzyl)oxy)nicotinamides represent a new class of SIRT2 inhibitors that are attractive candidates for further lead optimization in our continued effort to explore selective inhibition of SIRT2 as a potential therapy for Parkinson's disease.

  11. A Model for Nitrogen Chemistry in Oxy-Fuel Combustion of Pulverized Coal

    OpenAIRE

    Hashemi, Hamid; Hansen, Stine; Toftegaard, Maja Bøg; Pedersen, Kim Hougaard; Jensen, Anker Degn; Dam-Johansen, Kim; Glarborg, Peter

    2011-01-01

    In this work, a model for the nitrogen chemistry in the oxy-fuel combustion of pulverized coal has been developed. The model is a chemical reaction engineering type of model with a detailed reaction mechanism for the gas-phase chemistry, together with a simplified description of the mixing of flows, heating and devolatilization of particles, and gas–solid reactions. The model is validated by comparison with entrained flow reactor results from the present work and from the literature on pulver...

  12. Nonmethane hydrocarbon and oxy hydrocarbon measurements during the 2002 New England Air Quality Study

    Science.gov (United States)

    Goldan, Paul D.; Kuster, William C.; Williams, Eric; Murphy, Paul C.; Fehsenfeld, Fred C.; Meagher, James

    2004-11-01

    Nonmethane hydrocarbons (NMHCs) and oxy hydrocarbons (oxy HCs) were measured aboard the National Oceanic and Atmospheric Administration research vessel Ronald H. Brown during the New England Air Quality Study from 13 July to 10 August 2002 by an online dual gas chromatographic instrument with two separate analytical columns equipped, respectively, with flame ionization and mass spectrometer detectors. Measurements, taken each half hour, included C2 to C10 alkanes, C2 to C5 alkenes, alcohols and ketones, C6 to C9 aromatics, and biogenic volatile compounds including six monoterpenes, isoprene and its immediate oxidation products methacrolein and methylvinylketone. All compounds have been categorized by their contribution to the OH loss rate calculated for 298K and 1 atm. Large temporal variability was observed for all compounds. Airflow from the Providence, Rhode Island/Boston, Massachusetts, urban corridor northeast to the New Hampshire coast was usually heavily laden with NMHCs and oxy HCs of anthropogenic origin. Comparison of specific compound ratios with automotive tunnel studies suggested that these were predominantly mobile source emissions. When such flow occurred during daylight hours, these urban plumes were accompanied by increases in ozone in the 80 to 120 ppbv range. About equally as often, much less chemically mature NMHC plumes were encountered near the New Hampshire coast. Ozone was titrated out of these latter plumes, and the unusually high mixing ratios of C4 and C5 alkenes suggested that their source was partly gasoline vapor release rather than mobile source emissions. In the New England coastal region explored, in spite of the large anthropogenic NMHC input during periods of offshore flow, OH loss with hydrocarbons was frequently dominated by compounds of biogenic origin. During periods of cleaner marine air inflow the OH loss rate was dominated by reaction with methane and with oxy HCs, predominantly acetone, formaldehyde, and acetaldehyde.

  13. Crystal structure of (E)-4-hy-droxy-N'-(3-meth-oxy-benzyl-idene)benzohydrazide.

    Science.gov (United States)

    Chantrapromma, Suchada; Prachumrat, Patcharawadee; Ruanwas, Pumsak; Boonnak, Nawong; Kassim, Mohammad B

    2016-09-01

    The title compound, C15H14N2O3, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit that differ in the orientation of the 3-meth-oxy-phenyl group with respect to the methyl-idenebenzohydrazide unit. The dihedral angles between the two benzene rings are 24.02 (10) and 29.30 (9)° in mol-ecules A and B, respectively. In mol-ecule A, the meth-oxy group is twisted slightly relative to its bound benzene ring, with a Cmeth-yl-O-C-C torsion angle of 14.2 (3)°, whereas it is almost co-planar in mol-ecule B, where the corresponding angle is -2.4 (3)°. In the crystal, the mol-ecules are linked by N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds, as well as by weak C-H⋯O inter-actions, forming sheets parallel to the bc plane. The N-H⋯O hydrogen bond and weak C-H⋯O inter-action link different mol-ecules (A⋯B) whereas both O-H⋯N and O-H⋯O hydrogen bonds link like mol-ecules (A⋯A) and (B⋯B). Pairs of inversion-related B mol-ecules are stacked approximately along the a axis by π-π inter-actions in which the distance between the centroids of the 3-meth-oxy-phenyl rings is 3.5388 (12) Å. The B mol-ecules also participate in weak C-H⋯π inter-actions between the 4-hy-droxy-phenyl and the 3-meth-oxy-phenyl rings.

  14. NON-INTRUSIVE GAS-PHASE THERMOMETRY FOR INDUSTRIAL OXY-FUEL BURNERS

    Directory of Open Access Journals (Sweden)

    J. W. Tröger

    2015-03-01

    Full Text Available The use of oxy-fuel combustion processes is of large interest for several industrial fields applications since it offers the advantages of low NOx emissions in combination with high combustion temperatures even without additional preheating. For optimization of such processеs a detailed understanding based on precise experimental data is necessary. So far there is still a lack of precise experimental data achieved with high spatial and temporal resolution from industrial relevant turbulent oxy-fuel combustion processes. Beside species concentration information the gas phase temperature is of utmost importance for an improved understanding of the basic chemical reactions and the pollutant formation. The coherent anti-Stokes Raman spectroscopy (CARS technique is a very well suited laser based tool for a non-intrusive investigation of such turbulent high temperature combustion processes. In this work we analysed an industrial 400 kW oxy-fuel burner with the help of O2 based vibrational CARS system which is integrated in an industrial relevant test furnace. The burner is fed with pure oxygen and natural gas at an equivalence ratio of =0.9. At one downstream position temporal and spatial resolved temperatures were measured along a 600 mm line. Additional air sucked in from the environment seems to influence the gas phase temperature significantly.

  15. Crystal structure of (E)-2-hy-droxy-4'-meth-oxy-aza-stilbene.

    Science.gov (United States)

    Chantrapromma, Suchada; Kaewmanee, Narissara; Boonnak, Nawong; Chantrapromma, Kan; Ghabbour, Hazem A; Fun, Hoong-Kun

    2015-06-01

    The title aza-stilbene derivative, C14H13NO2 {systematic name: (E)-2-[(4-meth-oxy-benzyl-idene)amino]-phenol}, is a product of the condensation reaction between 4-meth-oxy-benzaldehyde and 2-amino-phenol. The mol-ecule adopts an E conformation with respect to the azomethine C=N bond and is almost planar, the dihedral angle between the two substituted benzene rings being 3.29 (4)°. The meth-oxy group is coplanar with the benzene ring to which it is attached, the Cmeth-yl-O-C-C torsion angle being -1.14 (12)°. There is an intra-molecular O-H⋯N hydrogen bond generating an S(5) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming zigzag chains along [10-1]. The chains are linked via C-H⋯π inter-actions, forming a three-dimensional structure.

  16. Effects of (Oxy-Fluorination on Various High-Performance Yarns

    Directory of Open Access Journals (Sweden)

    Iris Kruppke

    2016-08-01

    Full Text Available In this work, typical high-performance yarns are oxy-fluorinated, such as carbon fibers, ultra-high-molecular-weight polyethylene, poly(p-phenylene sulfide and poly(p-phenylene terephthalamide. The focus is on the property changes of the fiber surface, especially the wetting behavior, structure and chemical composition. Therefore, contact angle, XPS and tensile strength measurements are performed on treated and untreated fibers, while SEM is utilized to evaluate the surface structure. Different results for the fiber materials are observed. While polyethylene exhibits a relevant impact on both surface and bulk properties, polyphenylene terephthalamide and polyphenylene sulfide are only affected slightly by (oxy-fluorination. The wetting of carbon fiber needs higher treatment intensities, but in contrast to the organic fibers, even its textile-physical properties are enhanced by the treatment. Based on these findings, the capability of (oxy-fluorination to improve the adhesion of textiles in fiber-reinforced composite materials can be derived.

  17. Crystal structures of 4-meth-oxy-N-(4-methyl-phenyl)benzene-sulfonamide and N-(4-fluoro-phenyl)-4-meth-oxy-benzene-sulfonamide.

    Science.gov (United States)

    Rodrigues, Vinola Z; Preema, C P; Naveen, S; Lokanath, N K; Suchetan, P A

    2015-11-01

    Crystal structures of two N-(ar-yl)aryl-sulfonamides, namely, 4-meth-oxy-N-(4-methyl-phen-yl)benzene-sulfonamide, C14H15NO3S, (I), and N-(4-fluoro-phen-yl)-4-meth-oxy-benzene-sulfonamide, C13H12FNO3S, (II), were determined and analyzed. In (I), the benzene-sulfonamide ring is disordered over two orientations, in a 0.516 (7):0.484 (7) ratio, which are inclined to each other at 28.0 (1)°. In (I), the major component of the sulfonyl benzene ring and the aniline ring form a dihedral angle of 63.36 (19)°, while in (II), the planes of the two benzene rings form a dihedral angle of 44.26 (13)°. In the crystal structure of (I), N-H⋯O hydrogen bonds form infinite C(4) chains extended in [010], and inter-molecular C-H⋯πar-yl inter-actions link these chains into layers parallel to the ab plane. The crystal structure of (II) features N-H⋯O hydrogen bonds forming infinite one dimensional C(4) chains along [001]. Further, a pair of C-H⋯O inter-molecular inter-actions consolidate the crystal packing of (II) into a three-dimensional supra-molecular architecture.

  18. Characterization of OxyR as a negative transcriptional regulator that represses catalase production in Corynebacterium diphtheriae.

    Directory of Open Access Journals (Sweden)

    Ju-Sim Kim

    Full Text Available Corynebacterium diphtheriae and Corynebacterium glutamicum each have one gene (cat encoding catalase. In-frame Δcat mutants of C. diphtheriae and C. glutamicum were hyper-sensitive to growth inhibition and killing by H(2O(2. In C. diphtheriae C7(β, both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. Prototypic OxyR in Escherichia coli senses oxidative stress and it activates katG transcription and catalase production in response to H(2O(2. In contrast, exposure of C. diphtheriae C7(β to H(2O(2 did not stimulate transcription of cat. OxyR from C. diphtheriae and C. glutamicum have 52% similarity with E. coli OxyR and contain homologs of the two cysteine residues involved in H(2O(2 sensing by E. coli OxyR. In-frame ΔoxyR deletion mutants of C. diphtheriae C7(β, C. diphtheriae NCTC13129, and C. glutamicum were much more resistant than their parental wild type strains to growth inhibition by H(2O(2. In the C. diphtheriae C7(β ΔoxyR mutant, cat transcripts were about 8-fold more abundant and catalase activity was about 20-fold greater than in the C7(β wild type strain. The oxyR gene from C. diphtheriae or C. glutamicum, but not from E. coli, complemented the defect in ΔoxyR mutants of C. diphtheriae and C. glutamicum and decreased their H(2O(2 resistance to the level of their parental strains. Gel-mobility shift, DNaseI footprint, and primer extension assays showed that purified OxyR from C. diphtheriae C7(β bound, in the presence or absence of DTT, to a sequence in the cat promoter region that extends from nucleotide position -55 to -10 with respect to the +1 nucleotide in the cat ORF. These results demonstrate that OxyR from C. diphtheriae or C. glutamicum functions as a transcriptional repressor of the cat gene by a mechanism that is independent of oxidative stress induced by H(2O(2.

  19. Characterization of OxyR as a negative transcriptional regulator that represses catalase production in Corynebacterium diphtheriae.

    Science.gov (United States)

    Kim, Ju-Sim; Holmes, Randall K

    2012-01-01

    Corynebacterium diphtheriae and Corynebacterium glutamicum each have one gene (cat) encoding catalase. In-frame Δcat mutants of C. diphtheriae and C. glutamicum were hyper-sensitive to growth inhibition and killing by H(2)O(2). In C. diphtheriae C7(β), both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. Prototypic OxyR in Escherichia coli senses oxidative stress and it activates katG transcription and catalase production in response to H(2)O(2). In contrast, exposure of C. diphtheriae C7(β) to H(2)O(2) did not stimulate transcription of cat. OxyR from C. diphtheriae and C. glutamicum have 52% similarity with E. coli OxyR and contain homologs of the two cysteine residues involved in H(2)O(2) sensing by E. coli OxyR. In-frame ΔoxyR deletion mutants of C. diphtheriae C7(β), C. diphtheriae NCTC13129, and C. glutamicum were much more resistant than their parental wild type strains to growth inhibition by H(2)O(2). In the C. diphtheriae C7(β) ΔoxyR mutant, cat transcripts were about 8-fold more abundant and catalase activity was about 20-fold greater than in the C7(β) wild type strain. The oxyR gene from C. diphtheriae or C. glutamicum, but not from E. coli, complemented the defect in ΔoxyR mutants of C. diphtheriae and C. glutamicum and decreased their H(2)O(2) resistance to the level of their parental strains. Gel-mobility shift, DNaseI footprint, and primer extension assays showed that purified OxyR from C. diphtheriae C7(β) bound, in the presence or absence of DTT, to a sequence in the cat promoter region that extends from nucleotide position -55 to -10 with respect to the +1 nucleotide in the cat ORF. These results demonstrate that OxyR from C. diphtheriae or C. glutamicum functions as a transcriptional repressor of the cat gene by a mechanism that is independent of oxidative stress induced by H(2)O(2).

  20. 新型OxyPlateTM厌氧系统隔离眼部厌氧菌的评估%Evaluation of the new OxyPlateTM Anaerobic System for the isolation of ocular anaerobic bacteria

    Institute of Scientific and Technical Information of China (English)

    Emily K. Deschler; Paul P. Thompson; Regis Paul Kowalski

    2013-01-01

    目的:厌氧细菌可引起眼部感染,我们测试OxyPlateTM厌氧系统(OxyPlateTM Anaerobic System,OXY)隔离可引起眼部疾病的厌氧细菌.方法:OXY不需要直接的厌氧条件(比如厌氧袋,罐),将其与常规的厌氧袋培养基相比.琼脂培养基上眼部厌氧细菌菌株在好氧和厌氧条件下(厌氧袋)行标准的菌落计数:(1)OXY(好氧);(2)5%羊血(sheep blood,SB);(3)巧克力琼脂;(4)Schaedler琼脂.测试的眼部体外培养细菌来自眼内炎,泪囊炎,包括10个丙酸杆菌和3个放线菌种类.在每个培养条件下,每个细菌菌落计数隔离,排名从大到小,并在非参数比较下确定最佳的培养条件.结果:所有的厌氧条件对于厌氧菌株呈阳性反应.厌氧菌在有氧条件下的SB和Schaedler的琼脂中无法增长.痤疮丙酸杆菌在巧克力琼脂中生长稀疏.作为一种厌氧系统,在厌氧袋SB分离比OXY(P=0.0028)和巧克力琼脂(P=0.0028)分离出更多的菌落数.结论:虽然OXY经测试并没比其他的厌氧系统更高效,它似乎是一个合理隔离厌氧细菌的替代方法.其琼脂培养基在一个专门设计的盘并不需要厌氧袋使得OXY优于其他厌氧系统.%AIM: Anaerobic bacteria can cause ocular infections. We tested the OxyPlateTM Anaerobic System (OXY) to isolate pertinent anaerobic bacteria that can cause ocular disease.METHODS: OXY, which does not require direct anaerobic conditions (i.e. bags, jars), was compared to conventional isolation of incubating culture media in anaerobic bags. Standard colonies counts were performed on anaerobic ocular bacterial isolates under aerobic and anaerobic conditions (anaerobic bags) using agar media: 1) OXY (aerobic only), 2) 5% sheep blood (SB), 3) Chocolate, and 4) Schaedler. The bacteria tested were de-identified ocular isolates cultured from endophthalmitis and dacryocystitis that include 10 Propionibacterium acnes and 3 Actinomyces species. The colony counts for each bacteria isolate, on each

  1. (E)-3-[3,4-Bis(meth-oxy-methoxy)phen-yl]-1-(7-hy-droxy-5-meth-oxy-2,2-dimethyl-chroman-8-yl)prop-2-en-1-one.

    Science.gov (United States)

    Hashim, Nur Athirah; Ahmad, Farediah; Basar, Norazah; Awang, Khalijah; Ng, Seik Weng

    2011-09-01

    The reaction of 5,6-(2,2-dimethyl-chroman-yl)-2-hy-droxy-4-meth-oxy-acetophenone and 3,4-bis-(meth-oxy-meth-yloxy)benzaldehyde affords the intense orange title chalcone derivative, C(25)H(30)O(8). The two benzene rings are connected through a -C(=O)-CH=CH- (propenone) unit, which is in an E conformation; the ring with the hy-droxy substitutent is aligned at 19.5 (2)° with respect to this unit, whereas the ring with the meth-oxy-meth-yloxy substituent is aligned at 9.3 (3)°. The dihedral angle between the rings is 19.38 (10)°. The hy-droxy group engages in an intra-molecular O-H⋯O hydrogen bond with the carbonyl O atom of the propenone unit, generating an S(5) ring.

  2. A comparison between two NIRS oximeters (INVOS, OxyPrem) using measurement on the arm of adults and head of infants after caesarean section

    DEFF Research Database (Denmark)

    Hyttel-Sorensen, Simon; Hessel, Trine Witzner; la Cour, Amalia;

    2014-01-01

    Previously the NIRS oximeter OxyPrem was calibrated by comparison to the INVOS in a blood-lipid phantom. The aim of the present study was to test this calibration clinically. During vasculur occlusions in 10 adults and after birth in 25 term infants the relationship was OxyPrem = 1.24 x INVOS - 2...

  3. 40 CFR 721.7700 - Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3...

    Science.gov (United States)

    2010-07-01

    ...-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (3:1). 721.7700 Section 721.7700... Poly(oxy-1,2-ethanediyl), α-hydro-ω-(oxiranylmethoxy)-, ether with 2-ethyl-2-(hydroxymethyl)-1,3... substance identified as poly(oxy-1,2-ethanediyl),α-hydro-ω-(oxiranylmethoxy)-, ether with...

  4. FutureGen 2.0 Oxy-combustion Large Scale Test – Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Kenison, LaVesta [URS, Pittsburgh, PA (United States); Flanigan, Thomas [URS, Pittsburgh, PA (United States); Hagerty, Gregg [URS, Pittsburgh, PA (United States); Gorrie, James [Air Liquide, Kennesaw, GA (United States); Leclerc, Mathieu [Air Liquide, Kennesaw, GA (United States); Lockwood, Frederick [Air Liquide, Kennesaw, GA (United States); Falla, Lyle [Babcock & Wilcox and Burns McDonnell, Kansas City, MO (United States); Macinnis, Jim [Babcock & Wilcox and Burns McDonnell, Kansas City, MO (United States); Fedak, Mathew [Babcock & Wilcox and Burns McDonnell, Kansas City, MO (United States); Yakle, Jeff [Babcock & Wilcox and Burns McDonnell, Kansas City, MO (United States); Williford, Mark [Futuregen Industrial Alliance, Inc., Morgan County, IL (United States); Wood, Paul [Futuregen Industrial Alliance, Inc., Morgan County, IL (United States)

    2016-04-01

    The primary objectives of the FutureGen 2.0 CO2 Oxy-Combustion Large Scale Test Project were to site, permit, design, construct, and commission, an oxy-combustion boiler, gas quality control system, air separation unit, and CO2 compression and purification unit, together with the necessary supporting and interconnection utilities. The project was to demonstrate at commercial scale (168MWe gross) the capability to cleanly produce electricity through coal combustion at a retrofitted, existing coal-fired power plant; thereby, resulting in near-zeroemissions of all commonly regulated air emissions, as well as 90% CO2 capture in steady-state operations. The project was to be fully integrated in terms of project management, capacity, capabilities, technical scope, cost, and schedule with the companion FutureGen 2.0 CO2 Pipeline and Storage Project, a separate but complementary project whose objective was to safely transport, permanently store and monitor the CO2 captured by the Oxy-combustion Power Plant Project. The FutureGen 2.0 Oxy-Combustion Large Scale Test Project successfully achieved all technical objectives inclusive of front-end-engineering and design, and advanced design required to accurately estimate and contract for the construction, commissioning, and start-up of a commercial-scale "ready to build" power plant using oxy-combustion technology, including full integration with the companion CO2 Pipeline and Storage project. Ultimately the project did not proceed to construction due to insufficient time to complete necessary EPC contract negotiations and commercial financing prior to expiration of federal co-funding, which triggered a DOE decision to closeout its participation in the project. Through the work that was completed, valuable technical, commercial, and programmatic lessons were learned. This project has significantly advanced the development of near-zero emission technology and will

  5. Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation

    Energy Technology Data Exchange (ETDEWEB)

    Rue, David

    2013-09-30

    The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis

  6. Respiration of midges (Diptera; Chironomidae) in British Columbian lakes: oxy-regulation, temperature and their role as palaeo-indicators

    DEFF Research Database (Denmark)

    Brodersen, Klaus Peter; Pedersen, Ole; Walker, Ian R.;

    2008-01-01

    1. The specific respiration rate of 13 chironomid taxa and Chaoborus were measured to test the hypothesis of the relation between a species' ability to regulate their oxygen uptake and their distributional patterns among nine study lakes in British Columbia, Canada. 2. Respiration patterns...... of individual taxa were modelled using piecewise linear regression with break point and simple hyperbolic functions. Three types of respiration curves were identified: (i) classical oxy-conformers (e.g. littoral Cricotopus) which cannot sustain a sufficient oxygen uptake with decreasing oxygen availability; (ii......) oxy-regulators (e.g. profundal Chironomus) which can regulate and maintain a constant respiration until a certain critical point and (iii) oxy-stressors (Micropsectra) which increase their respiration rate with decreasing oxygen availability until a critical point. 3. Respiration was measured at two...

  7. Crystal structure of (E)-N-[(E)-3-(4-meth-oxy-phen-yl)allyl-idene]naphthalen-1-amine.

    Science.gov (United States)

    Lee, Jae Kyun; Cha, Joo Hwan; Cho, Yong Seo; Min, Sun-Joon; Lee, Joon Kyun

    2014-11-01

    In the title compound, C20H17NO, the dihedral angle between the mean planes of the 4-meth-oxy-phenyl ring and the naphthalene ring is 69.50 (7)°. The meth-oxy group is almost coplanar with the benzene ring to which it is connected [Cb-Cb-Om-Cm torsion angle of -7.9 (2)°; b = benzene and m = meth-oxy] and the imine group displays a C-C-N=C torsion angle is -57.2 (2)°. The imine (C=N) group has an E conformation. In the crystal, weak π-π inter-actions between the benzene rings [centroid-centroid distance = 3.7781 (10) Å] are observed.

  8. Sulphation of calcium-based sorbents in circulating fluidised beds under oxy-fuel combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Garcia-Labiano; Luis F. de Diego; Alberto Abad; Pilar Gayan; Margarita de las Obras-Loscertales; Aranzazu Rufas; Juan Adanez [Instituto de Carboquimica (CSIC), Zaragoza (Spain). Dept. Energy and Environment

    2009-07-01

    Sulphur Retention (SR) by calcium-based sorbents is a process highly dependent on the temperature and CO{sub 2} concentration. In circulating fluidised beds combustors (CFBC's) operating under oxy-fuel conditions, the sulphation process takes place in atmospheres enriched in CO{sub 2} with bed concentrations that can vary from 40 to 95%. Under so high CO{sub 2} concentrations, very different from that in conventional coal combustion atmosphere with air, the calcination and sulphation behaviour of the sorbent must be defined to optimise the SR process in the combustor. The objective of this work was to determine the SO{sub 2} retention capacity of a Spanish limestone at typical oxy-fuel conditions in CFBC's. Long term duration tests of sulphation (up to 24 h), to simulate the residence time of sorbents in CFBC's, were carried out by thermogravimetric analysis (TGA). Clear behaviour differences were found under calcining and non-calcining conditions. Especially relevant was the result obtained at calcining conditions but close to the thermodynamic temperature given for sorbent calcination. This situation must be avoided in CFBC's because the CO{sub 2} produced inside the particle during calcination can destroy the particles if a non-porous sulphate product layer has been formed around the particle. The effect of the main variables on the sorbent sulphation such as SO{sub 2} concentration, temperature, and particle size were analysed in the long term TGA tests. These data were also used to determine the kinetic parameters for the sulphation under oxy-fuel combustion conditions, which were able to adequately predict the sulphation conversion values in a wide range of operating conditions. 20 refs., 5 figs., 2 tabs.

  9. Innovative oxy-coal combustion process suitable for future and more efficient zero emission power plants

    Energy Technology Data Exchange (ETDEWEB)

    Benelli, G.; Malavasi, M.; Girardi, G. [ENEL Ricerca (Italy)

    2007-07-01

    The problem with CO{sub 2} capture from a flue gas stream is related to its low concentration, which makes the process of separation very energy-intensive, complex and, as a result, expensive. The CO{sub 2} separation process can be optimized by increasing the concentration of CO{sub 2} and reducing nitrogen concentration in the stream as it happens, in the oxy-fuel combustion process. In such a case, the oxidant flow is typically a mixture of oxygen, steam and carbon dioxide, with a very low concentration of nitrogen. Since the oxy-combustion process leads to very high temperatures, flue gases must be circulating through the chemical reactor to keep the combustion adiabatic temperature below acceptable values, due to the limits imposed by material resistance. This paper focuses on an innovative oxy-coal combustion process named ISOTHERM{reg_sign}, based on a flameless combustion technique which is mentioned in recent literature also as 'Mild' combustion. The combustion process takes place within a pressurized and refractory-lined furnace, approaching temperatures close to 2000 K. The process has been experienced at pressurized conditions up to 4 bar on a 5 MW pilot plant for thousands of hours. In this paper, starting from a detailed description of the process, results obtained by the preliminary experimental tests are presented and discussed. Then, a development and demonstration program to assess the suitability of this technology for zero emission power generation at large scale in one of the units of Brindisi power station is presented. 10 refs., 5 figs., 2 tabs.

  10. Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Choudhuri, Ahsan [Univ. Of Texas, El Paso, TX (United States)

    2013-09-30

    Oxy-fuel combustion has been used previously in a wide range of industrial applications. Oxy- combustion is carried out by burning a hydrocarbon fuel with oxygen instead of air. Flames burning in this configuration achieve higher flame temperatures which present opportunities for significant efficiency improvements and direct capture of CO2 from the exhaust stream. In an effort to better understand and characterize the fundamental flame characteristics of oxy-fuel combustion this research presents the experimental measurements of flame stability of various oxyfuel flames. Effects of H2 concentration, fuel composition, exhaust gas recirculation ratio, firing inputs, and burner diameters on the flame stability of these fuels are discussed. Effects of exhaust gas recirculation i.e. CO2 and H2O (steam) acting as diluents on burner operability are also presented. The roles of firing input on flame stability are then analyzed. For this study it was observed that many oxy-flames did not stabilize without exhaust gas recirculation due to their higher burning velocities. In addition, the stability regime of all compositions was observed to decrease as the burner diameter increased. A flashback model is also presented, using the critical velocity gradient gF) values for CH4-O2-CO2 flames. The second part of the study focuses on the experimental measurements of the flow field characteristics of premixed CH4/21%O2/79%N2 and CH4/38%O2/72%CO2 mixtures at constant firing input of 7.5 kW, constant, equivalence ratio of 0.8, constant swirl number of 0.92 and constant Reynolds Numbers. These measurements were taken in a swirl stabilized combustor at atmospheric pressure. The flow field visualization using Particle Imaging Velocimetry (PIV) technique is implemented to make a better understanding of the turbulence characteristics of

  11. Process Simulation of Oxy-combustion CO2 Capture in Cement Plant

    OpenAIRE

    2014-01-01

    The objectives of this master thesis have been to model and simulate oxy-combustion CO2 capture in a cement plant. The model developed is a process simulation of the calcination process with varying degree of air in-leakage, where heat is supplied by combustion in an oxygen rich environment, followed by capture of the CO2. The further gas separation after H2O condensation to achieve the required CO2 quality was evaluated. In addition to the process simulations, a review of literature related ...

  12. Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bradley R. [Univ. of Utah, Salt Lake City, UT (United States); Fry, Andrew R. [Univ. of Utah, Salt Lake City, UT (United States); Senior, Constance L. [Univ. of Utah, Salt Lake City, UT (United States); Shim, Hong Shig [Univ. of Utah, Salt Lake City, UT (United States); Otten, Brydger Van [Univ. of Utah, Salt Lake City, UT (United States); Wendt, Jost [Univ. of Utah, Salt Lake City, UT (United States); Shaddix, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tree, Dale [Brigham Young Univ., Provo, UT (United States)

    2010-06-01

    This report summarizes Year 2 results of a research program designed to use multi-scale experimental studies and fundamental theoretical models to characterize and predict the impacts of retrofit of existing coal-fired utility boilers for oxy-combustion. Year 2 focused extensively on obtaining experimental data from the bench-scale, lab-scale and pilot-scale reactors. These data will be used to refine and validate submodels to be implemented in CFD simulations of full-scale boiler retrofits. Program tasks are on schedule for Year 3 completion. Both Year 2 milestones were completed on schedule and within budget.

  13. The Sequestration of Oxy-Polybrominated Diphenyl Ethers in the Nudibranchs Miamira magnifica and Miamira miamirana

    OpenAIRE

    2016-01-01

    A series of oxy-polybrominated diphenyl ethers (O-PBDEs) has been isolated from the extracts of Miamira magnifica and Miamira miamirana collected from Queensland, Australia. M. magnifica sequesters the new OH-PBDE 1 and six known OH-PBDEs containing four to six bromines (2–7). M. miamirana also accumulates known tribromo- and tetrabromo OMe-PBDEs 8–10 in both mantle and viscera tissues. To date, Miamira is the only genus of the family Chromodorididae that is known to incorporate O-PBDEs, rath...

  14. Clinical application of OxyContin hydrochloride controlled release tablets in treatment of pain suffered from advanced cancer

    Institute of Scientific and Technical Information of China (English)

    Wenwu Wang; Xuenong OuYang; Zongyang Yu; Zhangshu Chen

    2012-01-01

    Objective: The aim of this study was to evaluate the efficacy and adverse reactions of OxyContin hydrochloride controlled release tablets in the treatment of moderate or severe pain in patients with terminal cancer and to observe any improvement on the cancer patients' quality of life. Methods: Sixty-eight patients with moderate or severe cancer pain were treated with OxyContin hydrochloride controlled release tablets. The initial dose was 5 mg/12h, or 1/2 that of the standard morphine regimen. During the course of treatment, the dosage was adjusted according to the patients' condition until the pain completely disappeared or nearly did so. Each patient received a treatment for at least 15 days. At the same time, adverse reactions, the quality of life and scores for the intensity of pain were observed and recorded [1]. Results: The final titrated dosage of OxyContin was as follows: the patients in 30 cases (44.1%) received a dosage of ≤ 30 mg/d, those in 16 cases (23.5%) received a dosage of 31 to 60 mg/d, those in 18 cases (26.5%) received a dosage of 61 to 120 mg/d and those in 4 cases (5.9%) received a dosage of ≥ 120 mg/d. The overall rate of relief from pain was 95.6%, among which the rates of excellent, effective and moderate relief were respectively 39.7%, 48.5% and 7.4%. OxyContin had mild adverse reactions and patients' quality of life was markedly improved. Conclusion: OxyContin is effective in treatment of moderate and severe cancer pain. The adverse reactions of OxyContin are mild, and the drug can significantly improve the quality of life of patients with cancer pain.

  15. Crystal structure of ethyl (E)-4-(4-chlorophen-yl)-4-meth-oxy-2-oxobut-3-enoate.

    Science.gov (United States)

    Flores, Darlene Correia; Vicenti, Juliano Rosa de Menezes; Pereira, Bruna Ávila; da Silva, Gabriele Marques Dias; Zambiazi, Priscilla Jussiane

    2014-09-01

    In the title compound, C13H13ClO4, the dihedral angle between the chloro-benezene ring and the least-squares plane through the 4-meth-oxy-2-oxobut-3-enoate ethyl ester residue (r.m.s. deviation = 0.0975 Å) is 54.10 (5)°. In the crystal, mol-ecules are connected by meth-oxy-ketone and benzene-carboxyl-ate carbonyl C-H⋯O inter-actions, generating a supra-molecular layer in the ac plane.

  16. Development & automation of a novel [(18)F]F prosthetic group, 2-[(18)F]-fluoro-3-pyridinecarboxaldehyde, and its application to an amino(oxy)-functionalised Aβ peptide.

    Science.gov (United States)

    Morris, Olivia; Gregory, J; Kadirvel, M; Henderson, Fiona; Blykers, A; McMahon, Adam; Taylor, Mark; Allsop, David; Allan, Stuart; Grigg, J; Boutin, Herve; Prenant, Christian

    2016-10-01

    2-[(18)F]-Fluoro-3-pyridinecarboxaldehyde ([(18)F]FPCA) is a novel, water-soluble prosthetic group. It's radiochemistry has been developed and fully-automated for application in chemoselective radiolabelling of amino(oxy)-derivatised RI-OR2-TAT peptide, (Aoa-k)-RI-OR2-TAT, using a GE TRACERlab FX-FN. RI-OR2-TAT is a brain-penetrant, retro-inverso peptide that binds to amyloid species associated with Alzheimer's Disease. Radiolabelled (Aoa-k)-RI-OR2-TAT was reproducibly synthesised and the product of the reaction with FPCA has been fully characterised. In-vivo biodistribution of [(18)F]RI-OR2-TAT has been measured in Wistar rats.

  17. Nano sized bismuth oxy chloride by metal organic chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jagdale, Pravin, E-mail: pravin.jagdale@polito.it [Department of Applied Science and Technology (DISAT), Politecnico di Torino, 10129 (Italy); Castellino, Micaela [Center for Space Human Robotics, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Marrec, Françoise [Laboratory of Condensed Matter Physics, University of Picardie Jules Verne (UPJV), Amiens 80039 (France); Rodil, Sandra E. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexicom (UNAM), Mexico D.F. 04510 (Mexico); Tagliaferro, Alberto [Department of Applied Science and Technology (DISAT), Politecnico di Torino, 10129 (Italy)

    2014-06-01

    Metal organic chemical vapour deposition (MOCVD) method was used to prepare thin films of bismuth based nano particles starting from bismuth salts. Nano sized bismuth oxy chloride (BiOCl) crystals were synthesized from solution containing bismuth chloride (BiCl{sub 3}) in acetone (CH{sub 3}-CO-CH{sub 3}). Self-assembly of nano sized BiOCl crystals were observed on the surface of silicon, fused silica, copper, carbon nanotubes and aluminium substrates. Various synthesis parameters and their significant impact onto the formation of self-assembled nano-crystalline BiOCl were investigated. BiOCl nano particles were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and Micro-Raman spectroscopy. These analyses confirm that bismuth nanometer-sized crystal structures showing a single tetragonal phase were indeed bismuth oxy chloride (BiOCl) square platelets 18–250 nm thick and a few micrometres wide.

  18. Characteristics modeling for supercritical circulating fluidized bed boiler working in oxy-combustion technology

    Directory of Open Access Journals (Sweden)

    Balicki Adrian

    2014-06-01

    Full Text Available Among the technologies which allow to reduce greenhouse gas emission, mainly carbon dioxide, special attention deserves the idea of ‘zeroemission’ technology based on boilers working in oxy-combustion technology. In the paper the results of analyses of the influence of changing two quantities, namely oxygen share in oxidant produced in the air separation unit, and oxygen share in oxidant supplied to the furnace chamber on the selected characteristics of a steam boiler including the degree of exhaust gas recirculation, boiler efficiency and adiabatic flame temperature, was examined. Due to the possibility of the integration of boiler model with carbon dioxide capture, separation and storage installation, the subject of the analysis was also to determine composition of the flue gas at the outlet of a moisture condensation installation. Required calculations were made using a model of a supercritical circulating fluidized bed boiler working in oxy-combustion technology, which was built in a commercial software and in-house codes.

  19. System approach to the analysis of an integrated oxy-fuel combustion power plant

    Science.gov (United States)

    Ziębik, Andrzej; Gładysz, Paweł

    2014-09-01

    Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2. Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the `input-output' method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.

  20. System approach to the analysis of an integrated oxy-fuel combustion power plant

    Directory of Open Access Journals (Sweden)

    Ziębik Andrzej

    2014-09-01

    Full Text Available Oxy-fuel combustion (OFC belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production. The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2. Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the ‘input-output’ method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost of an advanced integrated OFC power plant.

  1. Effect of biomass blending on coal ignition and burnout during oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    B. Arias; C. Pevida; F. Rubiera; J.J. Pis [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2008-09-15

    Oxy-fuel combustion is a GHG abatement technology in which coal is burned using a mixture of oxygen and recycled flue gas, to obtain a rich stream of CO{sub 2} ready for sequestration. An entrained flow reactor was used in this work to study the ignition and burnout of coals and blends with biomass under oxy-fuel conditions. Mixtures of CO{sub 2}/O{sub 2} of different concentrations were used and compared with air as reference. A worsening of the ignition temperature was detected in CO{sub 2}/O{sub 2} mixtures when the oxygen concentration was the same as that of the air. However, at an oxygen concentration of 30% or higher, an improvement in ignition was observed. The blending of biomass clearly improves the ignition properties of coal in air. The burnout of coals and blends with a mixture of 79%CO{sub 2}-21%O{sub 2} is lower than in air, but an improvement is achieved when the oxygen concentration is 30 or 35%. The results of this work indicate that coal burnout can be improved by blending biomass in CO{sub 2}/O{sub 2} mixtures. 26 refs., 7 figs., 1 tab.

  2. Crystal structure of 3-(2,5-di-meth-oxy-phen-yl)propionic acid.

    Science.gov (United States)

    Bugenhagen, Bernhard; Al Jasem, Yosef; AlAzani, Mariam; Thiemann, Thies

    2015-05-01

    In the crystal of the title compound, C11H14O4, the aromatic ring is almost coplanar with the 2-position meth-oxy group with which it subtends a dihedral of 0.54 (2)°, while the 5-position meth-oxy group makes a corresponding dihedral angle of just 5.30 (2)°. The angle between the mean planes of the aromatic ring and the propionic acid group is 78.56 (2)°. The fully extended propionic side chain is in a trans configuration with a C-C-C-C torsion angle of -172.25 (7)°. In the crystal, hydrogen bonding is limited to dimer formation via R 2 (2)(8) rings. The hydrogen-bonded dimers are stacked along the b axis. The average planes of the two benzene rings in a dimer are parallel to each other, but at an offset of 4.31 (2) Å. Within neighbouring dimers along the [101] direction, the average mol-ecular benzene planes are almost perpendicular to each other, with a dihedral angle of 85.33 (2)°.

  3. Respiration rate and oxy-regulatory capacity in cold stenothermal chironomids.

    Science.gov (United States)

    Lencioni, Valeria; Bernabò, Paola; Vanin, Stefano; Di Muro, Paolo; Beltramini, Mariano

    2008-09-01

    The effects of temperature and oxygen saturation on the respiration rate of two cold stenothermal chironomids, Diamesa insignipes and Pseudodiamesa branickii were investigated. Fourth instar larvae were collected in winter in a glacio-rhithral stream (1300 m a.s.l., Alps, NE-Italy) and their respiration rate was measured with a Clark's electrode in the range 0-14 degrees C. The respiration rate was significantly higher in D. insignipes than in P. branickii at low temperatures (respiration rate at 25% oxygen saturation) and b(1)/b(2) (slope ratio in piecewise linear regression), and lower values of P(c) (critical pressure) and I (initial decrease) were recorded in P. branickii than in D. insignipes. These values are compatible with oxy-regulatory behaviour in P. branickii, whereas D. insignipes appeared to be almost an oxy-conformer. On the basis of this autoecological information, new implications regarding survival of species from cold, high altitude habitats under changing climatic conditions are made.

  4. Tantalum (oxy)nitrides: preparation, characterisation and enhancement of photo-Fenton-like degradation of atrazine under visible light.

    Science.gov (United States)

    Du, Yingxun; Zhao, Lu; Su, Yaling

    2011-11-15

    Tantalum (oxy)nitrides were prepared by the nitridation of Ta(2)O(5) and were added to a photo-Fenton-like system to enhance Fe(3+) reduction and atrazine degradation under visible light. The samples were characterized by XRD, XPS, DRS and BET analyses. XPS analysis showed that the nitrogen content of the tantalum (oxy)nitride samples increased noticeably with the nitridation temperature and nitridation time but slightly with the flow rate of NH(3). XRD results showed Ta(2)O(5) was first converted to TaON and then to Ta(3)N(5) when the nitridation temperature increased. DRS analysis showed that the sample obtained at 800°C displayed the strongest absorption of visible light. However, the ability of the tantalum (oxy)nitrides to reduce Fe(3+) did not increase continuously with the nitrogen content. Sample 7 (700°C, [Formula: see text] , 6h) showed the highest level of photocatalytic activity for Fe(3+) reduction. This is because the photocatalytic activity of TaON for Fe(3+) reduction is higher than that of Ta(3)N(5). And a slight synergetic effect was observed between TaON and Ta(3)N(5). With the addition of sample 7, H(2)O(2) decomposition and atrazine degradation were significantly accelerated in a photo-Fenton-like system under visible light. The regenerated tantalum (oxy)nitrides catalyst displayed considerably stable performance for atrazine degradation.

  5. Nitrogen oxides, sulfur trioxide, and mercury emissions during oxy-fuel fluidized bed combustion of Victorian brown coal.

    Science.gov (United States)

    Roy, Bithi; Chen, Luguang; Bhattacharya, Sankar

    2014-12-16

    This study investigates, for the first time, the NOx, N2O, SO3, and Hg emissions from combustion of a Victorian brown coal in a 10 kWth fluidized bed unit under oxy-fuel combustion conditions. Compared to air combustion, lower NOx emissions and higher N2O formation were observed in the oxy-fuel atmosphere. These NOx reduction and N2O formations were further enhanced with steam in the combustion environment. The NOx concentration level in the flue gas was within the permissible limit in coal-fired power plants in Victoria. Therefore, an additional NOx removal system will not be required using this coal. In contrast, both SO3 and gaseous mercury concentrations were considerably higher under oxy-fuel combustion compared to that in the air combustion. Around 83% of total gaseous mercury released was Hg(0), with the rest emitted as Hg(2+). Therefore, to control harmful Hg(0), a mercury removal system may need to be considered to avoid corrosion in the boiler and CO2 separation units during the oxy-fuel fluidized-bed combustion using this coal.

  6. 77 FR 52018 - Oxy Midstream Strategic Development, LLC, Magellan Midstream Partners, L.P.; Notice of Petition...

    Science.gov (United States)

    2012-08-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Oxy Midstream Strategic Development, LLC, Magellan Midstream Partners, L.P... Strategic Development, LLC and Magellan Midstream Partners, L.P., on behalf of BridgeTex Pipeline...

  7. Hyperfine interactions in soybean and lupin oxy-leghemoglobins studied using Mössbauer spectroscopy with a high velocity resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. [University of Delhi South Campus, Department of Biochemistry (India); Alenkina, I. V. [Ural Federal University, Department of Physical Techniques and Devices for Quality Control, Institute of Physics and Technology (Russian Federation); Zakharova, A. P. [Ural Federal University, Department of Experimental Physics, Institute of Physics and Technology (Russian Federation); Oshtrakh, M. I., E-mail: oshtrakh@gmail.com; Semionkin, V. A. [Ural Federal University, Department of Physical Techniques and Devices for Quality Control, Institute of Physics and Technology (Russian Federation)

    2015-04-15

    A comparative study of monomeric soybean and lupin leghemoglobins in the oxy-form was carried out using Mössbauer spectroscopy with a high velocity resolution at 90 K. The {sup 57}Fe hyperfine parameters of measured spectra were evaluated and compared with possible structural differences in the heme Fe(II)–O {sub 2} bond.

  8. Comparative electron microscopy and image analysis of oxy- and deoxy-hemocyanin from the spiny lobster Panulirus interruptus

    NARCIS (Netherlands)

    Haas, Felix de; Breemen, Jan F.L. van; Boekema, Egbert J.; Keegstra, Wilko; Bruggen, Ernst F.J. van

    1993-01-01

    Structural differences between oxy-hemocyanin and deoxy-hemocyanin from the spiny lobster P. interruptus were studied by electron microscopy and image analysis of negatively stained preparations. Projections of the hexameric P. interruptus hemocyanin from electron microscopy were compared with simul

  9. Visible-light-enhanced interactions of hydrogen sulfide with composites of zinc (oxy)hydroxide with graphite oxide and graphene.

    Science.gov (United States)

    Seredych, Mykola; Mabayoje, Oluwaniyi; Bandosz, Teresa J

    2012-01-17

    Composites of zinc(oxy)hydroxide-graphite oxide and of zinc(oxy)hydroxide-graphene were used as adsorbents of hydrogen sulfide under ambient conditions. The initial and exhausted samples were characterized by XRD, FTIR, potentiometric titration, EDX, thermal analysis, and nitrogen adsorption. An increase in the amount of H(2)S adsorbed/oxidized on their surfaces in comparison with that of pure Zn(OH)(2) is linked to the structure of the composite, the relative number of terminal hydroxyls, and the kind of graphene-based phase used. Although terminal groups are activated by a photochemical process, the graphite oxide component owing to the chemical bonds with the zinc(oxy)hydroxide phase and conductive properties helps in electron transfer, leading to more efficient oxygen activation via the formation of superoxide ions. Elemental sulfur, zinc sulfide, sulfite, and sulfate are formed on the surface. The formation of sulfur compounds on the surface of zinc(oxy)hydroxide during the course of the breakthrough experiments and thus Zn(OH)(2)-ZnS heterojunctions can also contribute to the increased surface activity of our materials. The results show the superiority of graphite oxide in the formation of composites owing to its active surface chemistry and the possibility of interface bond formation, leading to an increase in the number of electron-transfer reactions.

  10. Adsorption of Oxy-Anions in the Teaching Laboratory: An Experiment to Study a Fundamental Environmental Engineering Problem

    Science.gov (United States)

    D'Arcy, Mitch; Bullough, Florence; Moffat, Chris; Borgomeo, Edoardo; Teh, Micheal; Vilar, Ramon; Weiss, Dominik J.

    2014-01-01

    Synthesizing and testing bicomposite adsorbents for the removal of environmentally problematic oxy-anions is high on the agenda of research-led universities. Here we present a laboratory module successfully developed at Imperial College London that introduces the advanced undergraduate student in engineering (chemical, civil, earth) and science…

  11. Characterization of ashes from a 100 kWth pilot-scale circulating fluidized bed with oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.H.; Wang, C.B.; Tan, Y.W.; Jia, L.F.; Anthony, E.J. [Natural Resources Canada, Ottawa, ON (Canada)

    2011-09-15

    Oxy-fuel combustion experiments have been carried out on an oxygen-fired 100 kW(th) mini-circulating fluidized bed combustion (CFBC) facility. Coal and petroleum coke were used as fuel together with different limestones (and fixed Ca:S molar ratios) premixed with the fuel, for in situ SO{sub 2} capture. The bed ash (BA) and fly ash (FA) samples produced from this unit were collected and characterized to obtain physical and chemical properties of the ash samples. The characterization methods used included X-ray fluorescence (XRF), X-ray diffraction (XRD), char carbon and free lime analysis, thermogravimetric analysis (TGA), and surface analysis. The main purpose of this work is to characterize the CFBC ashes from oxy-fuel firing to obtain a better understanding of the combustion process, and to identify any significant differences from the ash generated by a conventional air-fired CFBC. The primary difference in the sulfur capture mechanism between atmospheric air-fired and oxy-fuel FBC, at typical FBC temperatures (similar to 850{sup o}C), is that, in the air-fired case the limestone sorbents calcine, whereas the partial pressure of CO{sub 2} in oxy-fuel FBC is high enough to prevent calcination, and hence the sulfation process should mimic that seen in pressurized FBC (PFBC). Here, the char carbon content in the fly ash was much higher than that in the bed ash, and was also high by comparison with ash obtained from conventional commercial air-firing CFBC units. In addition, measurements of the free lime content in the bed and fly ash showed that the unreacted Ca sorbent was present primarily as CaCO{sub 3}, indicating that sulfur capture in the oxy-fuel combustor occurred via direct sulfation.

  12. Laminar oxy-fuel diffusion flame supported by an oxygen-permeable-ion-transport membrane

    KAUST Repository

    Hong, Jongsup

    2013-03-01

    A numerical model with detailed gas-phase chemistry and transport was used to predict homogeneous fuel conversion processes and to capture the important features (e.g., the location, temperature, thickness and structure of a flame) of laminar oxy-fuel diffusion flames stabilized on the sweep side of an oxygen permeable ion transport membrane (ITM). We assume that the membrane surface is not catalytic to hydrocarbon or syngas oxidation. It has been demonstrated that an ITM can be used for hydrocarbon conversion with enhanced reaction selectivity such as oxy-fuel combustion for carbon capture technologies and syngas production. Within an ITM unit, the oxidizer flow rate, i.e., the oxygen permeation flux, is not a pre-determined quantity, since it depends on the oxygen partial pressures on the feed and sweep sides and the membrane temperature. Instead, it is influenced by the oxidation reactions that are also dependent on the oxygen permeation rate, the initial conditions of the sweep gas, i.e., the fuel concentration, flow rate and temperature, and the diluent. In oxy-fuel combustion applications, the sweep side is fuel-diluted with CO2, and the entire unit is preheated to achieve a high oxygen permeation flux. This study focuses on the flame structure under these conditions and specifically on the chemical effect of CO2 dilution. Results show that, when the fuel diluent is CO2, a diffusion flame with a lower temperature and a larger thickness is established in the vicinity of the membrane, in comparison with the case in which N2 is used as a diluent. Enhanced OH-driven reactions and suppressed H radical chemistry result in the formation of products with larger CO and H2O and smaller H2 concentrations. Moreover, radical concentrations are reduced due to the high CO2 fraction in the sweep gas. CO2 dilution reduces CH3 formation and slows down the formation of soot precursors, C2H2 and C2H4. The flame location impacts the species diffusion and heat transfer from the

  13. Potent DGAT1 Inhibitors in the Benzimidazole Class with a Pyridyl-oxy-cyclohexanecarboxylic Acid Moiety.

    Science.gov (United States)

    He, Shuwen; Hong, Qingmei; Lai, Zhong; Wu, Zhicai; Yu, Yang; Kim, David W; Ting, Pauline C; Kuethe, Jeffrey T; Yang, Ginger X; Jian, Tianying; Liu, Jian; Guiadeen, Deodial; Krikorian, Arto D; Sperbeck, Donald M; Sonatore, Lisa M; Wiltsie, Judyann; Chung, Christine C; Gibson, Jack T; Lisnock, JeanMarie; Murphy, Beth A; Gorski, Judith N; Liu, Jinqi; Chen, Dunlu; Chen, Xiaoli; Wolff, Michael; Tong, Sharon X; Madeira, Maria; Karanam, Bindhu V; Shen, Dong-Ming; Balkovec, James M; Pinto, Shirly; Nargund, Ravi P; DeVita, Robert J

    2013-08-08

    We report the design and synthesis of a series of novel DGAT1 inhibitors in the benzimidazole class with a pyridyl-oxy-cyclohexanecarboxylic acid moiety. In particular, compound 11A is a potent DGAT1 inhibitor with excellent selectivity against ACAT1. Compound 11A significantly reduces triglyceride excursion in lipid tolerance tests (LTT) in both mice and dogs at low plasma exposure. An in vivo study in mice with des-fluoro analogue 10A indicates that this series of compounds appears to distribute in intestine preferentially over plasma. The propensity to target intestine over plasma could be advantageous in reducing potential side effects since lower circulating levels of drug are required for efficacy. However, in the preclinical species, compound 11A undergoes cis/trans epimerization in vivo, which could complicate further development due to the presence of an active metabolite.

  14. Optimization and Characterization of High Velocity Oxy-fuel Sprayed Coatings: Techniques, Materials, and Applications

    Directory of Open Access Journals (Sweden)

    Maria Oksa

    2011-09-01

    Full Text Available In this work High Velocity Oxy-fuel (HVOF thermal spray techniques, spraying process optimization, and characterization of coatings are reviewed. Different variants of the technology are described and the main differences in spray conditions in terms of particle kinetics and thermal energy are rationalized. Methods and tools for controlling the spray process are presented as well as their use in optimizing the coating process. It will be shown how the differences from the starting powder to the final coating formation affect the coating microstructure and performance. Typical properties of HVOF sprayed coatings and coating performance is described. Also development of testing methods used for the evaluation of coating properties and current status of standardization is presented. Short discussion of typical applications is done.

  15. Numerical Simulation on Supersonic Flow in High-Velocity Oxy-Fuel Thermal Spray Gun

    Institute of Scientific and Technical Information of China (English)

    Hiroshi KATANODA; Hideki YAMAMOTO; Kazuyasu MATSUO

    2006-01-01

    This paper analyzes the behaviour of coating particles as well as the gas flow both inside and outside of the High-Velocity Oxy-Fuel (HVOF) thermal spray gun by using a quasi-one-dimensional analysis and a numerical simulation. The HVOF gun in the present analysis is an axially symmetric convergent-divergent nozzle with the design Mach number of 2.0. From the present analysis, the distributions of velocity and temperature of the coating particles flying inside and outside of the HVOF gun are predicted. The velocity and temperature of the coating particles at the exit of the gun calculated by the present method agree well with the previous experimental results. Therefore, the present method of calculation is considered to be useful for predicting the HVOF gas and particle flows.

  16. Aerodynamic Study on Supersonic Flows in High-Velocity Oxy-Fuel Thermal Spray Process

    Institute of Scientific and Technical Information of China (English)

    Hiroshi KATANODA; Takeshi MATSUOKA; Seiji KURODA; Jin KAWAKITA; Hirotaka FUKANUMA; Kazuyasu MATSUO

    2005-01-01

    @@ To clarify the characteristics of gas flow in high velocity oxy-fuel (HVOF) thermal spray gun, aerodynamic research is performed using a special gun. The gun has rectangular cross-sectional area and sidewalls of optical glass to visualize the internal flow. The gun consists of a supersonic nozzle with the design Mach number of 2.0 followed by a straight passage called barrel. Compressed dry air up to 0.78 MPa is used as a process gas instead of combustion gas which is used in a commercial HVOF gun. The high-speed gas flows with shock waves in the gun and jets are visualized by schlieren technique. Complicated internal and external flow-fields containing various types of shock wave as well as expansion wave are visualized.

  17. Thermal Degradation Characteristics and Kinetics of Oxy Combustion of Corn Residues

    Directory of Open Access Journals (Sweden)

    Poramate Sittisun

    2015-01-01

    Full Text Available Thermogravimetric analysis was used to investigate oxy combustion of corncob and stover. The biomass samples were heated from ambient temperature to 900°C at different heating rates of 10, 30, and 50 K/min. Both biomass samples showed similar weight loss patterns with three zones, corresponding to dehydration, devolatilization, and char combustion, but displayed different degradation temperatures. Increasing heating rate was found to shift the degradation patterns to higher temperatures. Decomposition rates of cob and stover may have been influenced by their lignocellulosic composition. The kinetic parameters of the thermal degradation process were also determined and compared using the Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose methods. Both methods were found to give similar values and patterns of activation energy against conversion fraction. The average values were found to be in similar magnitude to those reported in the literature, around 170 and 148 kJ/mol for cob and stover, respectively.

  18. Laser Raman spectrometric determination of oxy-anions in nuclear waste materials

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.G.

    1977-03-01

    Oxy-anions in complex nuclear process-waste materials are being determined by laser Raman spectrometry (LRS). The double internal-standard technique developed by Marston is applied to the simultaneous determination of up to x anions in alkaline solutions. The method of Marston has been extended to solutions prepared from the solids formed in nuclear waste storage tanks. As many as six anions, aluminate, chromate, nitrate, nitrite, phosphate, and sulfate, are simultaneously determined in about one hour. Carbonate may also be determined, but in the presence of the prevalent nitrate, a chemical separation is required. Individual methods have been relegated to a secondary status due to the many advantages of LRS. Advantages such as small sample size, speed of analysis, accuracy, and specificity will be discussed. The typical precision obtained for analyses in high concentration is around five percent relative standard deviation.

  19. The Sequestration of Oxy-Polybrominated Diphenyl Ethers in the Nudibranchs Miamira magnifica and Miamira miamirana

    Directory of Open Access Journals (Sweden)

    Ariyanti S. Dewi

    2016-10-01

    Full Text Available A series of oxy-polybrominated diphenyl ethers (O-PBDEs has been isolated from the extracts of Miamira magnifica and Miamira miamirana collected from Queensland, Australia. M. magnifica sequesters the new OH-PBDE 1 and six known OH-PBDEs containing four to six bromines (2–7. M. miamirana also accumulates known tribromo- and tetrabromo OMe-PBDEs 8–10 in both mantle and viscera tissues. To date, Miamira is the only genus of the family Chromodorididae that is known to incorporate O-PBDEs, rather than terpenes, in the mantle where the metabolites may play a putative role in chemical defense. The extract of M. magnifica was tested in a brine shrimp lethality assay and exhibited an LD50 of 58 μg/mL.

  20. Performance of a Wet Flue Gas Desulfurization Pilot Plant under Oxy-Fuel Conditions

    DEFF Research Database (Denmark)

    Hansen, Brian Brun; Fogh, Folmer; Knudsen, Niels Ole

    2011-01-01

    vol % CO2, at a holding tank pH 5.4, reduced the limestone dissolution rate significantly and thereby increased the residual, particulate limestone concentration in the gypsum slurry from 3.2 to 5.0 g/L slurry relative to a base-case (air-firing) experiment with a flue gas CO2 concentration around 7......, but an additional increase in desulfurization degree, from 94 to 97%, was obtained. Using a holding tank pH 5.0 (no adipic acid) returned both parameters to the levels observed in the base-case experiment.......Oxy-fuel firing is a promising technology that should enable the capture and storage of anthropogenic CO2 emissions from large stationary sources such as power plants and heavy industry. However, this new technology has a high energy demand for air separation and CO2 compression and storage...

  1. Oxy-fired boiler unit and method of operating the same

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Xinsheng; Zhang, Jundong; Joshi, Abhinaya; McCombe, James A.; Levasseur, Armand A.

    2016-12-06

    An oxy-combustion boiler unit is disclosed which includes a furnace for combusting fuel and for emitting flue gas resulting from combustion. The furnace has first, second and third combustion zones, and an air separation unit for separating oxygen gas from air and providing a first portion of the separated oxygen to a first oxidant flow, a second portion to a second oxidant flow, and a third portion of the separated oxygen gas to the first, second, and third zones of the furnace. A controller can cause the separated oxygen gas to be distributed so that the first and second oxygen flows have a desired oxygen content, and so that the first, second, and third zones of the furnace receive a desired amount of oxygen based on a combustion zone stoichiometry control.

  2. Structural and electrical characterisation of SrCe1-xYxOxi

    DEFF Research Database (Denmark)

    Phillips, R.J.; Bonanos, N.; Poulsen, F.W.;

    1999-01-01

    The acceptor-doped perovskite proton conductor SrCe1-xYxOxi (x = 0.025 to 0.20, xi = 3 - x/2) has been prepared and characterised using X-ray diffraction and AC impedance spectroscopy, and the effect of the yttrium dopant concentration on structure and electrical properties has been investigated. X-ray...... procedures and regions of ionic and p-type conduction have been identified. At 800 degrees C and at the water vapour partial pressure of 0.007 atm, the ionic conductivity showed a maximum at a doping level of x = 0.10, reaching a value of 5 mS/cm. The conductivity component appearing at low oxygen partial...

  3. Formation and Control of Sulfur Oxides in Sour Gas Oxy-Combustion: Prediction Using a Reactor Network Model

    KAUST Repository

    Bongartz, Dominik

    2015-11-19

    © 2015 American Chemical Society. Sour natural gas currently requires expensive gas cleanup before it can be used in power generation because it contains large amounts of hydrogen sulfide (H2S) and carbon dioxide (CO2) that entail a low heating value and highly corrosive combustion products. A potential alternative is to use the gas directly in a gas turbine process employing oxy-fuel combustion, which could eliminate the need for gas cleanup while also enabling the application of carbon capture and sequestration, possibly combined with enhanced oil recovery (EOR). However, the exact influence of an oxy-fuel environment on the combustion products of sour gas has not been quantified yet. In this work, we used a reactor network model for the combustor and the gas turbine together with our recently assembled and validated detailed chemical reaction mechanism for sour gas combustion to investigate the influence of some basic design parameters on the combustion products of natural gas and sour gas in CO2 or H2O diluted oxy-fuel combustion as well as in conventional air combustion. Our calculations show that oxy-fuel combustion produces up to 2 orders of magnitude less of the highly corrosive product sulfur trioxide (SO3) than air combustion, which clearly demonstrates its potential in handling sulfur containing fuels. Unlike in air combustion, in oxy-fuel combustion, SO3 is mainly formed in the flame zone of the combustor and is then consumed as the combustion products are cooled in the dilution zone of the combustor and the turbine. In oxy-fuel combustion, H2O dilution leads to a higher combustion efficiency than CO2 dilution. However, if the process is to be combined with EOR, CO2 dilution makes it easier to comply with the very low levels of oxygen (O2) required in the EOR stream. Our calculations also show that it might even be beneficial to operate slightly fuel-rich because this simultaneously decreases the O2 and SO3 concentration further. The flame zone

  4. Performance of Fe-Cr based WGS catalysts prepared by co-precipitation and oxi-precipitation methods

    Energy Technology Data Exchange (ETDEWEB)

    Marono, M.; Ruiz, E.; Sanchez, J.M. [CIEMAT, Energy Department, Combustion and Gasification Division, Avda Complutense, 22, 28040 Madrid (Spain); Martos, C.; Dufour, J.; Ruiz, A. [URJC, Department of Chemical and Environmental Technology, ESCET, C/Tulipan, s/n, 28933, Mostoles, Madrid (Spain)

    2009-11-15

    In this work the performance of Fe-Cr based WGS catalysts synthesized following two different methods (co-precipitation and oxy-precipitation) is studied under a wide range of operating conditions. A commercial Fe-Cr based WGS catalyst is used for comparison. The activity of the catalysts has been studied on simulated gases under conditions typical of oxygen pressurized gasification. The influence of main operating parameters, including temperature, space velocity and excess steam is evaluated in terms of hydrogen production and CO conversion. Catalytic performance has been evaluated from 200 C to 500 C, using gas space velocities between 2885 and 10000 h{sup -1} and steam to carbon monoxide ratios from 2 to 6.7. According to the results obtained in this work, the oxy-precipitation method has provided a suitable approach to synthesize highly active Fe-Cr based WGS catalysts. (author)

  5. Thermodynamic evaluation of supercritical oxy-type power plant with high-temperature three-end membrane for air separation

    Science.gov (United States)

    Kotowicz, Janusz; Balicki, Adrian; Michalski, Sebastian

    2014-09-01

    Among the technologies which allow to reduce greenhouse gas emissions, mainly of carbon dioxide, special attention deserves the idea of `zero-emission' technology based on boilers working in oxy-combustion technology. In the paper a thermodynamic analysis of supercritical power plant fed by lignite was made. Power plant consists of: 600 MW steam power unit with live steam parameters of 650 °C/30 MPa and reheated steam parameters of 670 °C/6 MPa; circulating fluidized bed boiler working in oxy-combustion technology; air separation unit and installation of the carbon dioxide compression. Air separation unit is based on high temperature membrane working in three-end technology. Models of steam cycle, circulation fluidized bed boiler, air separation unit and carbon capture installation were made using commercial software. After integration of these models the net electricity generation efficiency as a function of the degree of oxygen recovery in high temperature membrane was analyzed.

  6. New weighted sum of gray gases model applicable to Computational Fluid Dynamics (CFD) modeling of oxy-fuel combustion

    DEFF Research Database (Denmark)

    Yin, Chungen; Johansen, Lars Christian Riis; Rosendahl, Lasse;

    2010-01-01

    Radiation is the principal mode of heat transfer in furnaces. Models for gaseous radiative properties have been well established for air combustion. However, there is uncertainty regarding their applicability to oxy-fuel conditions. In this paper, a new and complete set of weighted sum of gray...... gases model (WSGGM) is derived, which is applicable to computational fluid dynamics (CFD) modeling of both air-fuel and oxy-fuel combustion. First, a computer code is developed to evaluate the emissivity of any gas mixture at any condition by using the exponential wide band model (EWBM...... into CFD simulations of combustion systems is given. Finally, as a demonstration, the new model is implemented into CFD modeling of two furnaces of very different beam lengths, respectively. The CFD results are compared with those based on the widely used WSGGM in literature, from which some useful...

  7. Thermodynamic evaluation of supercritical oxy-type power plant with high-temperature three-end membrane for air separation

    Directory of Open Access Journals (Sweden)

    Kotowicz Janusz

    2014-09-01

    Full Text Available Among the technologies which allow to reduce greenhouse gas emissions, mainly of carbon dioxide, special attention deserves the idea of ‘zero-emission’ technology based on boilers working in oxy-combustion technology. In the paper a thermodynamic analysis of supercritical power plant fed by lignite was made. Power plant consists of: 600 MW steam power unit with live steam parameters of 650 °C/30 MPa and reheated steam parameters of 670 °C/6 MPa; circulating fluidized bed boiler working in oxy-combustion technology; air separation unit and installation of the carbon dioxide compression. Air separation unit is based on high temperature membrane working in three-end technology. Models of steam cycle, circulation fluidized bed boiler, air separation unit and carbon capture installation were made using commercial software. After integration of these models the net electricity generation efficiency as a function of the degree of oxygen recovery in high temperature membrane was analyzed.

  8. The reactivity of lattice carbon and nitrogen species in molybdenum (oxy)carbonitrides prepared by single-source routes

    Energy Technology Data Exchange (ETDEWEB)

    AlShalwi, M. [WestCHEM, School of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Hargreaves, J.S.J., E-mail: Justin.Hargreaves@glasgow.ac.uk [WestCHEM, School of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Liggat, J.J.; Todd, D. [WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL (United Kingdom)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Molybdenum (oxy)carbonitrides have been prepared from single source routes. Black-Right-Pointing-Pointer Nitrogen species are more reactive than carbon species within the carbonitrides. Black-Right-Pointing-Pointer The reactivity of nitrogen species is a function of carbonitride composition. -- Abstract: Molybdenum (oxy)carbonitrides of different compositions have been prepared from hexamethylenetetramine molybdate and ethylenediamine molybdate precursors and the reactivity of the lattice carbon and nitrogen species within them has been determined by temperature programmed reduction and thermal volatilisation studies. Nitrogen is found to be much more reactive than carbon and the nature of its reactivity is influenced by composition with the presence of carbon enhancing the reactivity of nitrogen. The difference in reactivity observed indicates that molybdenum carbonitrides are not suitable candidates as reagents for which the simultaneous loss of nitrogen and carbon from the lattice would be desirable.

  9. Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout

    Energy Technology Data Exchange (ETDEWEB)

    Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

    2010-12-15

    This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

  10. Microwave-assisted synthesis of novel nonperipherally substituted metallophthalocyanines bearing (7-(trifluoromethyl)quinolin-4-yl)oxy groups

    OpenAIRE

    EVREN, Didem; YENİLMEZ, Hacer Yasemin; BURAT, Ayfer KALKAN

    2014-01-01

    The synthesis, characterization, and spectroscopic properties of novel nonperipherally tetrasubstituted metallophthalocyanines (zinc, cobalt, copper, manganese, and indium) bearing 4 (7-(trifluoromethyl)quinolin-4-yl)oxy units has been reported. The new compounds have been characterized using UV-Vis, IR, 1H NMR, 13C NMR, 19F NMR, and mass spectroscopic data. The absorption properties of these new complexes were compared to those of peripherally substituted phthalocyanine derivatives. Based on...

  11. Adsorption Mechanisms of Trivalent Gold onto Iron Oxy-Hydroxides: From the Molecular Scale to the Model

    Science.gov (United States)

    Cancès, Benjamin; Benedetti, Marc; Farges, François; Brown, Gordon E.

    2007-02-01

    Gold is a highly valuable metal that can concentrate in iron-rich exogenetic horizons such as laterites. An improved knowledge of the retention mechanisms of gold onto highly reactive soil components such as iron oxy-hydroxides is therefore needed to better understand and predict the geochemical behavior of this element. In this study, we use EXAFS information and titration experiments to provide a realistic thermochemical description of the sorption of trivalent gold onto iron oxy-hydroxides. Analysis of Au LIII-edge XAFS spectra shows that aqueous Au(III) adsorbs from chloride solutions onto goethite surfaces as inner-sphere square-planar complexes (Au(III)(OH,Cl)4), with dominantly OH ligands at pH > 6 and mixed OH/Cl ligands at lower pH values. In combination with these spectroscopic results, Reverse Monte Carlo simulations were used to constraint the possible sorption sites on the surface of goethite. Based on this structural information, we calculated sorption isotherms of Au(III) on Fe oxy-hydroxides surfaces, using the CD-MUSIC (Charge Distribution — MUlti SIte Complexation) model. The various Au(III)-sorbed species were identified as a function of pH, and the results of these EXAFS+CD-MUSIC models are compared with titration experiments. The overall good agreement between the predicted and measured structural models shows the potential of this combined approach to better model sorption processes of transition elements onto highly reactive solid surfaces such as goethite and ferrihydrite.

  12. Qualitative and quantitative event-specific PCR detection methods for oxy-235 canola based on the 3' integration flanking sequence.

    Science.gov (United States)

    Yang, Litao; Guo, Jinchao; Zhang, Haibo; Liu, Jia; Zhang, Dabing

    2008-03-26

    As more genetically modified plant events are approved for commercialization worldwide, the event-specific PCR method has become the key method for genetically modified organism (GMO) identification and quantification. This study reveals the 3' flanking sequence of the exogenous integration of Oxy-235 canola employing thermal asymmetric interlaced PCR (TAIL-PCR). On the basis of the revealed 3' flanking sequence, PCR primers and TaqMan probe were designed and qualitative and quantitative PCR assays were established for Oxy-235 canola. The specificity and limits of detection (LOD) and quantification (LOQ) of these two PCR assays were validated to as low as 0.1% for the relative LOD of qualitative PCR assay; the absolute LOD and LOQ were low to 10 and 20 copies of canola genomic DNA in quantitative PCR assay, respectively. Furthermore, ideal quantified results were obtained in the practical canola sample detection. All of the results indicate that the developed qualitative and quantitative PCR methods based on the revealed 3' integration flanking sequence are suitable for GM canola Oxy-235 identification and quantification.

  13. Determination of selected oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) in diesel and air particulate matter standard reference materials (SRMs).

    Science.gov (United States)

    Nocun, Margarete S; Schantz, Michele M

    2013-06-01

    Oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) have recently received much attention in discussions regarding the negative impacts of particulate matter (PM) on human health and the environment. The National Institute of Standards and Technology provides several environmental matrix standard reference materials (SRMs) with certified and reference values for polycyclic aromatic hydrocarbons (PAHs) and nitrated PAHs. In this study, the concentrations of oxygenated PAHs are determined in three air PM SRMs (1649b, 1648a, and 2786) and three diesel PM SRMs (1650b, 2975, and 1975) using two independent gas chromatography-mass spectrometry methods. Concentrations of oxy-PAHs were at the milligrams per kilogram level with higher overall concentrations in diesel PM (up to 50 mg/kg for 9,10-anthraquinone). One of the highest oxy-PAH concentrations (up to 5 mg/kg) measured in the air particulate SRMs was for 7,12-benz[a]anthracenquinone. These results suggest that oxygenated PAHs should not be neglected in the analysis of PM as their concentrations can be as high as those of some PAHs and are one to two orders of magnitude higher than those for nitro-PAHs.

  14. Crystal structure of 1-(8-meth-oxy-2H-chromen-3-yl)ethanone.

    Science.gov (United States)

    Koh, Dongsoo

    2014-09-01

    In the structure of the title compound, C12H12O3, the di-hydro-pyran ring is fused with the benzene ring. The di-hydro-pyran ring is in a half-chair conformation, with the ring O and methyl-ene C atoms positioned 1.367 (3) and 1.504 (4) Å, respectively, on either side of the mean plane formed by the other four atoms. The meth-oxy group is coplanar with the benzene ring to which it is connected [Cb-Cb-Om-Cm torsion angle = -0.2 (4)°; b = benzene and m = meth-oxy], and similarly the aldehyde is coplanar with respect to the double bond of the di-hydro-pyran ring [Cdh-Cdh-Ca-Oa = -178.1 (3)°; dh = di-hydro-pyran and a = aldehyde]. In the crystal, mol-ecules are linked by weak meth-yl-meth-oxy C-H⋯O hydrogen bonds into supra-molecular chains along the a-axis direction.

  15. Staged, High-Pressure Oxy-Combustion Technology: Development and Scale-Up

    Energy Technology Data Exchange (ETDEWEB)

    Axelbaum, Richard; Xia, Fei; Gopan, Akshay; Kumfer, Benjamin

    2014-09-30

    Washington University in St. Louis and its project partners are developing a unique pressurized oxy-combustion process that aims to improve efficiency and costs by reducing the recycling of flue gas to near zero. Normally, in the absence of recycled flue gas or another inert gas, combustion of fuel and oxygen results in a dramatic increase in temperature of the combustion products and radiant energy, as compared to combustion in air. High heat flux to the boiler tubes may result in a tube surface temperatures that exceed safe operating limits. In the Staged Pressurized Oxy-Combustion (SPOC) process, this problem is addressed by staging the delivery of fuel and by novel combustion design that allows control of heat flux. In addition, the main mode of heat transfer to the steam cycle is by radiation, as opposed to convection. Therefore, the requirement for recycling large amounts of flue gas, for temperature control or to improve convective heat transfer, is eliminated, resulting in a reduction in auxiliary loads. The following report contains a detailed summary of scientific findings and accomplishments for the period of Oct. 1, 2013 to Sept 30, 2014. Results of ASPEN process and CFD modelling activities aimed at improving the SPOC process and boiler design are presented. The effects of combustion pressure and fuel moisture on the plant efficiency are discussed. Combustor pressure is found to have only a minor impact beyond 16 bar. For fuels with moisture content greater than approx 30%, e.g. coal/water slurries, the amount of latent heat of condensation exceeds that which can be utilized in the steam cycle and plant efficiency is reduced significantly. An improved boiler design is presented that achieves a more uniform heat flux profile. In addition, a fundamental study of radiation in high-temperature, high-pressure, particle-laden flows is summarized which provides a more complete understanding of heat transfer in these unusual conditions and to allow for

  16. Radiation and convective heat transfer, and burnout in oxy-coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    J.P. Smart; P. O' Nions; G.S. Riley [RWE npower, Swindon (United Kingdom)

    2010-09-15

    Measurements of radiative and convective heat transfer, and carbon-in-ash have been taken on the RWEn 0.5 MWth combustion test facility (CTF) firing two different coals under oxy-fuel firing conditions. The two coals fired were a Russian Coal and a South African Coal. Recycle ratios were varied within the range of 65-75% dependent on coal. Furnace exit O{sub 2} values were maintained at 3% and 6% for the majority of tests. Air firing tests were also performed to generate baseline data. The work gives a comprehensive insight into the effect of oxy-fuel combustion on both radiative and convective heat transfer, and carbon-in-ash compared to air under dry simulated recycle conditions. Results have shown peak radiative heat flux values are inversely related to the recycle ratio for the two coals studied. Conversely, the convective heat flux values increase with increasing recycle ratio. It was also observed that the axial position of the peak in radiative heat flux moves downstream away from the burner as recycle ratio is increased. A 'working range' of recycle ratios exists where both the radiative and convective heat fluxes are comparable with air. Carbon-in-ash (CIA) was measured for selected conditions. For air firing of Russian Coal, the CIA for follows and expected trend with CIA decreasing with increasing furnace exit O{sub 2}. The CIA data for the two recycle ratios of 72% and 68% for the same coal show that the CIA values are lower than for air firing for corresponding furnace exit O{sub 2} levels and vary little with the value of furnace exit O{sub 2}. CIA measurements were taken for the South African Coal for a range of recycle ratios at 3% and 6% furnace exit O{sub 2} levels. Results indicate that the CIA values are lower for higher furnace exit O{sub 2}. 32 refs., 11 figs., 1 tab.

  17. Tantalum (oxy)nitrides: Preparation, characterisation and enhancement of photo-Fenton-like degradation of atrazine under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yingxun, E-mail: yxdu@niglas.ac.cn [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China); Zhao, Lu; Su, Yaling [Nanjing Institute of Geography and Limnology, State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing 210008 (China)

    2011-11-15

    Highlights: {yields} The photocatalytic activity of TaON for Fe{sup 3+} reduction is higher than that of Ta{sub 3}N{sub 5}. {yields} Atrazine degradation was accelerated significantly by tantalum (oxy)nitrides sample. {yields} The regenerated catalyst displays considerably stable performance for atrazine degradation. - Abstract: Tantalum (oxy)nitrides were prepared by the nitridation of Ta{sub 2}O{sub 5} and were added to a photo-Fenton-like system to enhance Fe{sup 3+} reduction and atrazine degradation under visible light. The samples were characterized by XRD, XPS, DRS and BET analyses. XPS analysis showed that the nitrogen content of the tantalum (oxy)nitride samples increased noticeably with the nitridation temperature and nitridation time but slightly with the flow rate of NH{sub 3}. XRD results showed Ta{sub 2}O{sub 5} was first converted to TaON and then to Ta{sub 3}N{sub 5} when the nitridation temperature increased. DRS analysis showed that the sample obtained at 800 {sup o}C displayed the strongest absorption of visible light. However, the ability of the tantalum (oxy)nitrides to reduce Fe{sup 3+} did not increase continuously with the nitrogen content. Sample 7 (700 {sup o}C, Q{sub NH{sub 3}}=0.3L/min, 6 h) showed the highest level of photocatalytic activity for Fe{sup 3+} reduction. This is because the photocatalytic activity of TaON for Fe{sup 3+} reduction is higher than that of Ta{sub 3}N{sub 5}. And a slight synergetic effect was observed between TaON and Ta{sub 3}N{sub 5}. With the addition of sample 7, H{sub 2}O{sub 2} decomposition and atrazine degradation were significantly accelerated in a photo-Fenton-like system under visible light. The regenerated tantalum (oxy)nitrides catalyst displayed considerably stable performance for atrazine degradation.

  18. Laboratory Investigations of the High Temperature Corrosion of Various Materials in Simulated oxy-fuel and Conventional Coal Firing

    Energy Technology Data Exchange (ETDEWEB)

    Folkeson, N.; Pettersson, J.; Svensson, J.E. [Chalmers Univ. of Technology (Sweden); Hjornhede, A. [Vattenfall Power Consultant AB (Sweden); Montgomery, M. [Vattenfall Heat Nordic/DTU Mekanik (Denmark); Bjurman, M. [Vattenfall Research and Development AB (Sweden)

    2009-07-01

    Laboratory exposures in horizontal tube furnaces were conducted to test various materials for corrosion resistance in simulated oxy-fuel firing and conventional coal firing environments. Two different exposures were done at 630 C for 672 hours. The reaction atmosphere, consisting of CO{sub 2}, H{sub 2}O, O{sub 2}, N{sub 2} and SO{sub 2}, was mixed to resemble that of oxy-fuel firing in the first exposure and that of conventional coal firing in the second exposure (N{sub 2} was added during the second exposure only). Four different materials were tested in the first exposure; Sanicro 63, Alloy 800HT, 304L and 304HCu. In the second exposure four different materials were tested; 304L, Alloy 800HT, Kanthal APMT and NiCrAl. Apart from cleaned sample coupons, some samples pre-exposed in a test rig under oxy-fuel conditions with lignite as fuel and some pre-exposed with bituminous coal as fuel were investigated in the first exposure. In the second exposure some samples were pre-exposed in a rig under conventional firing conditions with lignite as fuel. The corrosion attack on the investigated samples was analysed by gravimetry, x-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive x-ray (EDX). The SEM/EDX analysis was made on both the sample envelope and metallographic cross sections of the samples. The results show that there is small difference in the corrosion attack between the two environments. There was also little difference in oxide morphology and composition between cleaned samples and pre-exposed samples of the same material. The austenitic chromia former 304HCu suffered the most extensive corrosion attack in the oxy-fuel environment. In the conventional air firing environment 304L showed the highest mass gain. Chromia formers with higher chromium concentrations performed better, especially the super austenitic Alloy 800HT, with its high chromium concentration, formed a thin and protective corundum type oxide. The nickel based

  19. Crystal structures of bis-(phen-oxy)silicon phthalocyanines: increasing π-π inter-actions, solubility and disorder and no halogen bonding observed.

    Science.gov (United States)

    Lessard, Benoît H; Lough, Alan J; Bender, Timothy P

    2016-07-01

    We report the syntheses and characterization of three solution-processable phen-oxy silicon phthalocyanines (SiPcs), namely bis-(3-methyl-phen-oxy)(phthalocyanine)silicon [(3MP)2-SiPc], C46H30N8O2Si, bis-(2-sec-butyl-phen-oxy)(phthalocyanine)silicon [(2secBP)2-SiPc], C44H24I2N8O2Si, and bis-(3-iodo-phen-oxy)(phthalocyanine)silicon [(3IP)2-SiPc], C52H42N8O2Si. Crystals grown of these compounds were characterized by single-crystal X-ray diffraction and the π-π inter-actions between the aromatic SiPc cores were studied. It was determined that (3MP)2-SiPc has similar inter-actions to previously reported bis-(3,4,5-tri-fluoro-phen-oxy)silicon phthalocyanines [(345 F)2-SiPc] with significant π-π inter-actions between the SiPc groups. (3IP)2-SiPc and (2secBP)2-SiPc both experienced a parallel stacking of two of the peripheral aromatic groups. In all three cases, the solubility of these mol-ecules was increased by the addition of phen-oxy groups while maintaining π-π inter-actions between the aromatic SiPc groups. The solubility of (2secBP)2-SiPc was significantly higher than other bis-phen-oxy-SiPcs and this was exemplified by the higher observed disorder within the crystal structure.

  20. Accelerated Senescence and Enhanced Disease Resistance in Hybrid Chlorosis Lines Derived from Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii

    OpenAIRE

    Hiroki Nakano; Nobuyuki Mizuno; Yukio Tosa; Kentaro Yoshida; Pyoyun Park; Shigeo Takumi

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlyin...

  1. Accelerated senescence and enhanced disease resistance in hybrid chlorosis lines derived from interspecific crosses between tetraploid wheat and Aegilops tauschii.

    Science.gov (United States)

    Nakano, Hiroki; Mizuno, Nobuyuki; Tosa, Yukio; Yoshida, Kentaro; Park, Pyoyun; Takumi, Shigeo

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions.

  2. Defective ATM-Kap-1-mediated chromatin remodeling impairs DNA repair and accelerates senescence in progeria mouse model.

    Science.gov (United States)

    Liu, Baohua; Wang, Zimei; Ghosh, Shrestha; Zhou, Zhongjun

    2013-04-01

    ATM-mediated phosphorylation of KAP-1 triggers chromatin remodeling and facilitates the loading and retention of repair proteins at DNA lesions. Mouse embryonic fibroblasts (MEFs) derived from Zmpste24(-/-) mice undergo early senescence, attributable to delayed recruitment of DNA repair proteins. Here, we show that ATM-Kap-1 signaling is compromised in Zmpste24(-/-) MEFs, leading to defective DNA damage-induced chromatin remodeling. Knocking down Kap-1 rescues impaired chromatin remodeling, defective DNA repair and early senescence in Zmpste24(-/-) MEFs. Thus, ATM-Kap-1-mediated chromatin remodeling plays a critical role in premature aging, carrying significant implications for progeria therapy.

  3. Accelerated senescence and enhanced disease resistance in hybrid chlorosis lines derived from interspecific crosses between tetraploid wheat and Aegilops tauschii.

    Directory of Open Access Journals (Sweden)

    Hiroki Nakano

    Full Text Available Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions.

  4. Temperature Trends in Coal Char Combustion under Oxy-fuel Conditions for the Determination of Kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Samira [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hecht, Ethan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-08-01

    Oxy-fuel combustion technology with carbon capture and storage could significantly reduce global CO2 emissions, a greenhouse gas. Implementation can be aided by computational fluid dynamics (CFD) simulations, which require an accurate understanding of coal particle kinetics as they go through combustion in a range of environments. To understand the kinetics of pulverized coal char combustion, a heated flow reactor was operated under a wide range of experimental conditions. We varied the environment for combustion by modifying the diluent gas, oxygen concentration, gas flow rate, and temperature of the reactor/reacting gases. Measurements of reacting particle temperatures were made for a sub-bituminous and bituminous coal char, in environments with CO2 or N2 as the diluent gas, with 12, 24, and 36 vol-% oxygen concentration, at 50, 80, 100, and 200 standard liters per minute flowing through the reactor, reactor temperatures of 1200, 1400 K, at pressures slightly above atmospheric. The data shows consistent increasing particle temperature with increased oxygen concentration, reactor temperature and higher particle temperatures for N2 diluent than CO2. We also see the effects of CO2 gasification when different ranks of coal are used, and how the reduction in the temperature due to the CO2 diluent is greater for the coal char that has higher reactivity. Quantitative measurements for temperature are not yet complete due to ongoing calibration of detection systems.

  5. Relative phase of oscillations of cerebral oxy-hemoglobin and deoxy-hemoglobin concentrations during sleep

    Science.gov (United States)

    Pierro, Michele L.; Sassaroli, Angelo; Bergethon, Peter R.; Fantini, Sergio

    2012-02-01

    We present a near-infrared spectroscopy study of the instantaneous phase difference between spontaneous oscillations of cerebral deoxy-hemoglobin and oxy-hemoglobin concentrations ([Hb] and [HbO], respectively) in the low-frequency range, namely 0.04-0.12 Hz. We report phase measurements during the transitions between different sleep stages in a whole-night study of a human subject. We have found that the phase difference between [Hb] and [HbO] low-frequency oscillations tends to be greater in deep sleep (by ~96° on average) and REM sleep (by ~77° on average) compared to the awake state. In particular, we have observed progressive phase increases as the subject transitions from awake conditions into non-REM sleep stages N1, N2, and N3. Corresponding phase decreases were recorded in the reversed transitions from sleep stages N3 to N2, and N2 to awake. These results illustrate the physiological information content of phase measurements of [Hb] and [HbO] oscillations that reflect the different cerebral hemodynamic conditions of the different sleep stages, and that can find broader applicability in a wide range of near-infrared spectroscopy brain studies.

  6. Development of a biomass torrefaction process integrated with oxy-fuel combustion.

    Science.gov (United States)

    Tran, Khanh-Quang; Trinh, Trung Ngoc; Bach, Quang-Vu

    2016-01-01

    Torrefaction of forest residues was studied under conditions relevant to oxy-fuel combustion flue gases. The results showed that the torrefaction in CO2 had a lower solid mass yield (81.36%) than that (83.06%) in N2. Addition of steam into CO2 (CO2/H2O=1/0.7 mole/mole) resulted in a higher mass yield (83.30%) compared to 81.36% in CO2. The energy yield was consistently increased from 79.17% to 84.12% or 88.32% for the torrefaction in N2, CO2, or the CO2 and steam mixture, respectively. On the other hand, additions of O2 into the mixture of steam and CO2 led to reductions in both mass yield (from 83.30% to 82.57% or 76.44%) and energy yield (from 88.32% to 84.65% or 79.16%, for the torrefaction in steam and CO2 without O2, with 5% v/v, or 10% v/v of O2, respectively).

  7. Corrosion Performance of Fe-Based Alloys in Simulated Oxy-Fuel Environment

    Science.gov (United States)

    Zeng, Zuotao; Natesan, Ken; Cai, Zhonghou; Rink, David L.

    2017-02-01

    The long-term corrosion of Fe-based alloys in simulated oxy-fuel environment at 1023 K (750 °C) was studied. Detailed results are presented on weight change, scale thickness, internal penetration, microstructural characteristics of the corrosion products, and the cracking of scales for the alloys after exposure at 1023 K (750 °C) for up to 3600 hours. An incubation period during which the corrosion rate was low was observed for the alloys. After the incubation period, the corrosion accelerated, and the corrosion process followed linear kinetics. Effects of alloy, CaO-containing ash, and gas composition on the corrosion rate were also studied. In addition, synchrotron nanobeam X-ray analysis was employed to determine the phase and chemical composition of the oxide layers on the alloy surface. Results from these studies are being used to address the long-term corrosion performance of Fe-based alloys in various coal-ash combustion environments and to develop methods to mitigate high-temperature ash corrosion.

  8. Chemical effects of a high CO2 concentration in oxy-fuel combustion of methane

    DEFF Research Database (Denmark)

    Glarborg, Peter; Bentzen, L.L.B.

    2008-01-01

    in terms of a detailed chemical kinetic mechanism for hydrocarbon oxidation. On the basis of results of the present study, it can be expected that oxy-fuel combustion will lead to strongly increased CO concentrations in the near-burner region. The CO2 present will compete with O-2 for atomic hydrogen......The oxidation of methane in an atmospheric-pres sure flow reactor has been studied experimentally under highly diluted conditions in N-2 and CO2, respectively. The stoichiometry was varied from fuel-lean to fuel-rich, and the temperatures covered the range 1200-1800 K. The results were interpreted...... and lead to formation of CO through the reaction CO2 + H reversible arrow CO + OH. Reactions of CO2 with hydrocarbon radicals may also contribute to CO formation. The most important steps are those of singlet and triplet CH2 with CO2, while other radicals such as CH3 and CH are less important for consuming...

  9. Dynamic Exergy Method for Evaluating the Control and Operation of Oxy-Combustion Boiler Island Systems.

    Science.gov (United States)

    Jin, Bo; Zhao, Haibo; Zheng, Chuguang; Liang, Zhiwu

    2017-01-03

    Exergy-based methods are widely applied to assess the performance of energy conversion systems; however, these methods mainly focus on a certain steady-state and have limited applications for evaluating the control impacts on system operation. To dynamically obtain the thermodynamic behavior and reveal the influences of control structures, layers and loops, on system energy performance, a dynamic exergy method is developed, improved, and applied to a complex oxy-combustion boiler island system for the first time. The three most common operating scenarios are studied, and the results show that the flow rate change process leads to less energy consumption than oxygen purity and air in-leakage change processes. The variation of oxygen purity produces the largest impact on system operation, and the operating parameter sensitivity is not affected by the presence of process control. The control system saves energy during flow rate and oxygen purity change processes, while it consumes energy during the air in-leakage change process. More attention should be paid to the oxygen purity change because it requires the largest control cost. In the control system, the supervisory control layer requires the greatest energy consumption and the largest control cost to maintain operating targets, while the steam control loops cause the main energy consumption.

  10. Crystal structure of 4-(meth-oxy-carbon-yl)phenyl-boronic acid.

    Science.gov (United States)

    Flanagan, Keith J; Senge, Mathias O

    2015-10-01

    In the title compound, C8H9BO4, the meth-oxy-carbonyl group is rotated out of the plane of the benzene ring by 7.70 (6)°. In the crystal, mol-ecules are linked via pairs of O-H⋯O hydrogen bonds, involving the boronic acid OH groups, forming inversion dimers. The dimers are linked via O-H⋯O hydrogen bonds, involving a boronic acid OH group and the carbonyl O atom, forming undulating sheets parallel to (10-2). Within the sheets there are also C-H⋯O hydrogen bonds present, also involving the carbonyl O atom. The sheets are linked via C-H⋯π and offset face-to-face π-inter-actions between inversion-related mol-ecules [inter-centroid distance = 3.7843 (16) Å, inter-planar distance = 3.3427 (4) Å and offset = 1.744 Å], forming a three-dimensional structure.

  11. Oxy-acetylene driven laboratory scale shock tubes for studying blast wave effects

    CERN Document Server

    Courtney, Michael

    2011-01-01

    Instrumentation is needed to produce realistic blast waves in a laboratory setting. This paper describes the development and characterization of oxy-acetylene driven, laboratory scale shock tubes for use in studying blast injury, candidate armor materials, and material properties at blast loading rates. The pressure-time profiles show a true shock front and exponential decay characteristic of blast waves and have relevant durations. The modular design includes shock tube diameters of 27 mm and 41 mm, and a selection of peak pressures from 204 kPa to 920 kPa can be produced by selection of the driver section diameter and placement of the test sample. Characterization studies of several driver/driven section combinations showed consistent results, with peak pressures having 0.8 - 6.9 percent uncertainty in the mean. This shock tube design provides a more realistic blast profile than current air-driven shock tubes. In addition, operation does not require specialized personnel or facilities like most blast-driven...

  12. Evaluasi Pelaksanaan Praktik Oxy-Acetylene Welding di Jurusan Pendidikan Teknik Mesin FT UNY

    Directory of Open Access Journals (Sweden)

    Arif Marwanto

    2014-10-01

    Full Text Available The objectives of this study were: (1 to investigate the implementation of the curriculum (2 to examine the condition of the equipment used in Oxy-Acetylene Welding (OAW practices 3 to identify problems experienced by the students and the lecturers (4 to determine the students’achievement of OAW practices. This study was categorised into descriptive quantitative. It was explorative with the Context, Input, Process and Product (CIPP evaluation method. The objects of this study were the students in the course of OAW practices. The data collection techniques were documentation, observation and questionnaires administration. The data was analysed using descriptive analysis. The results showed that the implementation of the OAW practices curriculum was very effective with the mean scores of 93.4%. The problems experienced by the students were resulted from the materials, the equipment, the lecturers, the toolman, the workshop environment, and the jobsheets. Each of them contributed fairly to the problems. The problems consist of low motivation, low safety concerns, inadequate rooms, inadequate equipment and low quantity of practices. The students learning achievement was very good indicated by 60% of the students achieved the good score

  13. Corrosion Performance of Fe-Based Alloys in Simulated Oxy-Fuel Environment

    Science.gov (United States)

    Zeng, Zuotao; Natesan, Ken; Cai, Zhonghou; Rink, David L.

    2016-09-01

    The long-term corrosion of Fe-based alloys in simulated oxy-fuel environment at 1023 K (750 °C) was studied. Detailed results are presented on weight change, scale thickness, internal penetration, microstructural characteristics of the corrosion products, and the cracking of scales for the alloys after exposure at 1023 K (750 °C) for up to 3600 hours. An incubation period during which the corrosion rate was low was observed for the alloys. After the incubation period, the corrosion accelerated, and the corrosion process followed linear kinetics. Effects of alloy, CaO-containing ash, and gas composition on the corrosion rate were also studied. In addition, synchrotron nanobeam X-ray analysis was employed to determine the phase and chemical composition of the oxide layers on the alloy surface. Results from these studies are being used to address the long-term corrosion performance of Fe-based alloys in various coal-ash combustion environments and to develop methods to mitigate high-temperature ash corrosion.

  14. Residual stresses in high-velocity oxy-fuel metallic coatings

    Science.gov (United States)

    Totemeier, T. C.; Wright, R. N.; Swank, W. D.

    2004-06-01

    X-ray based residual stress measurements were made on type 316 stainless steel and Fe3Al coatings that were high-velocity oxy-fuel (HVOF) sprayed onto low-carbon and stainless steel substrates. Nominal coating thicknesses varied from 250 to 1500 µm. The effect of HVOF spray particle velocity on residual stress and deposition efficiency was assessed by preparing coatings at three different torch chamber pressures. The effect of substrate thickness on residual stress was determined by spraying coatings onto thick (6.4 mm) and thin (1.4 mm) substrates. Residual stresses were compressive for both coating materials and increased in magnitude with spray velocity. For coatings applied to thick substrates, near-surface residual stresses were essentially constant with increasing coating thickness. Differences in thermal expansion coefficient between low-carbon and stainless steels led to a 180 MPa difference in residual stress for Fe3Al coatings. Deposition efficiency for both materials is maximized at an intermediate (˜600 m/s) velocity. Considerations for X-ray measurement of residual stresses in HVOF coatings are also presented.

  15. Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

    DEFF Research Database (Denmark)

    Seo, Sang Woo; Kim, Donghyuk; Szubin, Richard;

    2015-01-01

    Three transcription factors (TFs), OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, SoxR, an...

  16. Thermally induced cation redistribution in Fe-bearing oxy-dravite and potential geothermometric implications

    Science.gov (United States)

    Bosi, Ferdinando; Skogby, Henrik; Hålenius, Ulf

    2016-05-01

    Iron-bearing oxy-dravite was thermally treated in air and hydrogen atmosphere at 800 °C to study potential changes in Fe, Mg and Al ordering over the octahedrally coordinated Y and Z sites and to explore possible applications to intersite geothermometry based on tourmaline. Overall, the experimental data (structural refinement, Mössbauer, infrared and optical absorption spectroscopy) show that heating Fe-bearing tourmalines results in disordering of Fe over Y and Z balanced by ordering of Mg at Y, whereas Al does not change appreciably. The Fe disorder depends on temperature, but less on redox conditions. The degree of Fe3+-Fe2+ reduction is limited despite strongly reducing conditions, indicating that the f O2 conditions do not exclusively control the Fe oxidation state at the present experimental conditions. Untreated and treated samples have similar short- and long-range crystal structures, which are explained by stable Al-extended clusters around the O1 and O3 sites. In contrast to the stable Al clusters that preclude any temperature-dependent Mg-Al order-disorder, there occurs Mg diffusion linked to temperature-dependent exchange with Fe. Ferric iron mainly resides around O2- at O1 rather than (OH)-, but its intersite disorder induced by thermal treatment indicates that Fe redistribution is the driving force for Mg-Fe exchange and that its diffusion rates are significant at these temperatures. With increasing temperature, Fe progressively disorders over Y and Z, whereas Mg orders at Y according to the order-disorder reaction: YFe + ZMg → ZFe + YMg. The presented findings are important for interpretation of the post-crystallization history of both tourmaline and tourmaline host rocks and imply that successful tourmaline geothermometers may be developed by thermal calibration of the Mg-Fe order-disorder reaction, whereas any thermometers based on Mg-Al disorder will be insensitive and involve large uncertainties.

  17. Coal pyrolysis and char burnout under conventional and oxy-fuel conditions

    Energy Technology Data Exchange (ETDEWEB)

    Al-Makhadmeh, L.; Maier, J.; Scheffknecht, G. [Stuttgart Univ. (Germany). Institut fuer Verfahrenstechnik und Dampfkesselwesen

    2009-07-01

    Coal utilization processes such as combustion or gasification generally involve several steps i.e., the devolatilization of organic materials, homogeneous reactions of volatile matter with the reactant gases, and heterogeneous reactions of the solid (char) with the reactant gases. Most of the reported work about coal pyrolysis and char burnout were performed at low temperatures under environmental conditions related to the air firing process with single particle tests. In this work, coal combustion under oxy-fuel conditions is investigated by studying coal pyrolysis and char combustion separately in practical scales, with the emphasis on improving the understanding of the effect of a CO{sub 2}-rich gas environment on coal pyrolysis and char burnout. Two coals, Klein Kopje a medium volatile bituminous coal and a low-rank coal, Lausitz coal were used. Coal pyrolysis in CO{sub 2} and N{sub 2} environments were performed for both coals at different temperatures in an entrained flow reactor. Overall mass release, pyrolysis gas concentrations, and char characterization were performed. For char characterization ultimate analysis, particle size, and BET surface area were measured. Chars for both coals were collected at 1150 C in both CO{sub 2} and N{sub 2} environments. Char combustion was performed in a once-through 20 kW test facility in O{sub 2}/CO{sub 2} and O{sub 2}/N{sub 2} atmospheres. Besides coal quality, oxygen partial pressure was chosen as a variable to study the effect of the gas environment on char burnout. In general, it is found that the CO{sub 2} environment and coal rank have a significant effect on coal pyrolysis and char burnout. (orig.)

  18. Oxy-acetylene driven laboratory scale shock tubes for studying blast wave effects.

    Science.gov (United States)

    Courtney, Amy C; Andrusiv, Lubov P; Courtney, Michael W

    2012-04-01

    This paper describes the development and characterization of modular, oxy-acetylene driven laboratory scale shock tubes. Such tools are needed to produce realistic blast waves in a laboratory setting. The pressure-time profiles measured at 1 MHz using high-speed piezoelectric pressure sensors have relevant durations and show a true shock front and exponential decay characteristic of free-field blast waves. Descriptions are included for shock tube diameters of 27-79 mm. A range of peak pressures from 204 kPa to 1187 kPa (with 0.5-5.6% standard error of the mean) were produced by selection of the driver section diameter and distance from the shock tube opening. The peak pressures varied predictably with distance from the shock tube opening while maintaining both a true blast wave profile and relevant pulse duration for distances up to about one diameter from the shock tube opening. This shock tube design provides a more realistic blast profile than current compression-driven shock tubes, and it does not have a large jet effect. In addition, operation does not require specialized personnel or facilities like most blast-driven shock tubes, which reduces operating costs and effort and permits greater throughput and accessibility. It is expected to be useful in assessing the response of various sensors to shock wave loading; assessing the reflection, transmission, and absorption properties of candidate armor materials; assessing material properties at high rates of loading; assessing the response of biological materials to shock wave exposure; and providing a means to validate numerical models of the interaction of shock waves with structures. All of these activities have been difficult to pursue in a laboratory setting due in part to lack of appropriate means to produce a realistic blast loading profile.

  19. Crystal structure of 4,5-bis-(3,4,5-tri-meth-oxy-phen-yl)-2H-1,2,3-triazole methanol monosolvate.

    Science.gov (United States)

    Madadi, Nikhil Reddy; Penthala, Narsimha Reddy; Bommagani, Shobanbabu; Parkin, Sean; Crooks, Peter A

    2014-10-01

    The title compound, C20H23N3O6·CH3OH, was synthesized by [3 + 2] cyclo-addition of (Z)-2,3-bis-(3,4,5-tri-meth-oxy-phen-yl)acrylo-nitrile with sodium azide and ammonium chloride in DMF/water. The central nitro-gen of the triazole ring is protonated. The dihedral angles between the triazole ring and the 3,4,5-tri-meth-oxy-phenyl ring planes are 34.31 (4) and 45.03 (5)°, while that between the 3,4,5-tri-meth-oxy-phenyl rings is 51.87 (5)°. In the crystal, the mol-ecules, along with two methanol solvent mol-ecules are linked into an R (4) 4(10) centrosymmetric dimer by N-H⋯O and O-H⋯N hydrogen bonds.

  20. Hepatotoxicity associated with weight loss or sports dietary supplements, including OxyELITE Pro™ - United States, 2013.

    Science.gov (United States)

    Chatham-Stephens, Kevin; Taylor, Ethel; Chang, Arthur; Peterson, Amy; Daniel, Johnni; Martin, Colleen; Deuster, Patricia; Noe, Rebecca; Kieszak, Stephanie; Schier, Josh; Klontz, Karl; Lewis, Lauren

    2017-01-01

    In September 2013, the Hawaii Department of Health (HDOH) was notified of seven adults who developed acute hepatitis after taking OxyELITE Pro™, a weight loss and sports dietary supplement. CDC assisted HDOH with their investigation, then conducted case-finding outside of Hawaii with FDA and the Department of Defense (DoD). We defined cases as acute hepatitis of unknown etiology that occurred from April 1, 2013, through December 5, 2013, following exposure to a weight loss or muscle-building dietary supplement, such as OxyELITE Pro™. We conducted case-finding through multiple sources, including data from poison centers (National Poison Data System [NPDS]) and FDA MedWatch. We identified 40 case-patients in 23 states and two military bases with acute hepatitis of unknown etiology and exposure to a weight loss or muscle building dietary supplement. Of 35 case-patients who reported their race, 15 (42.9%) reported white and 9 (25.7%) reported Asian. Commonly reported symptoms included jaundice, fatigue, and dark urine. Twenty-five (62.5%) case-patients reported taking OxyELITE Pro™. Of these 25 patients, 17 of 22 (77.3%) with available data were hospitalized and 1 received a liver transplant. NPDS and FDA MedWatch each captured seven (17.5%) case-patients. Improving the ability to search surveillance systems like NPDS and FDA MedWatch for individual and grouped dietary supplements, as well as coordinating case-finding with DoD, may benefit ongoing surveillance efforts and future outbreak responses involving adverse health effects from dietary supplements. This investigation highlights opportunities and challenges in using multiple sources to identify cases of suspected supplement associated adverse events. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  1. 智能OxiTop IS BOD测试仪测定水体BOD的研究

    Institute of Scientific and Technical Information of China (English)

    廖勇

    2004-01-01

    叙述了使用OxiTop IS BOD测试仪测定水体BOD的方法,实验结果表明,该法准确度和精密度完全符合监测的要求,同时探讨了仪器自动感测温度和压力、自动存储的智能检测特性,该仪器操作简便。值得广泛应用。

  2. Bis(6-meth-oxy-2-{[tris-(hydroxy-meth-yl)-meth-yl]-imino-meth-yl}phenolato)-copper(II) dihydrate.

    Science.gov (United States)

    Zhang, Xiutang; Wei, Peihai; Dou, Jianmin; Li, Bin; Hu, Bo

    2009-01-08

    In the title compound, [Cu(C(12)H(16)NO(5))(2)]·2H(2)O, the Cu(II) ion adopts a trans-CuN(2)O(4) octa-hedral geometry arising from two N,O,O'-tridentate 6-meth-oxy-2-{[tris-(hydroxy-meth-yl)meth-yl]-imino-meth-yl}phenolate ligands. The Jahn-Teller distortion of the copper centre is unusally small. In the crystal structure, O-H⋯O hydrogen bonds, some of which are bifurcated, link the component species.

  3. Diurnal and nocturnal measurements of PAH, nitro-PAH, and oxy-PAH compounds in atmospheric particulate matter of a sugar cane burning region

    Science.gov (United States)

    Souza, Kely F.; Carvalho, Lilian R. F.; Allen, Andrew G.; Cardoso, Arnaldo A.

    2014-02-01

    Polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs, and oxy-PAHs were studied in the atmospheric particulate matter of a subtropical rural region (São Paulo State, Brazil) affected by emissions from sugar cane burning. Diurnal and nocturnal samples were collected from May to June of 2010. In general, average PAH concentrations were significantly higher at night, suggesting that the compounds were predominantly emitted to the atmosphere during biomass burning (which was mainly performed at night). The maximum average PAH concentration was found for benzo[b]fluoranthene at night (2.9 ± 5.4 ng m-3). Among the nitro-PAH compounds, the highest average concentrations were obtained for 9-nitrophenanthrene in diurnal and nocturnal samples (1.5 ± 1.2 and 1.3 ± 2.1 ng m-3, respectively). In contrast to the PAH and nitro-PAH compounds, the oxy-PAHs could not be directly associated with sugar cane burning. The most abundant oxy-PAH compound was benzanthrone (1.6 ± 1.3 ng m-3) at night, followed by 9,10-anthraquinone (1.1 ± 0.9 ng m-3) and 9-fluorenone (0.4 ± 0.1 ng m-3) during the day. A correlation matrix was used to explore the origins of the different compounds. The data suggested that during the daytime, direct emissions (mainly in vehicle exhaust) contributed to the presence of PAHs, nitro-PAHs, and oxy-PAHs in air. Photochemical production also appeared to be a source of the majority of nitro-PAHs and oxy-PAHs, while photolysis could have contributed to removal of the nitro-PAHs during the daytime. At night, sugar cane burning emissions were the primary source of the PAHs and nitro-PAHs, with additional sources also contributing to the levels of oxy-PAHs in the atmosphere.

  4. 氧化苦参碱对癫痫大鼠学习记忆功能及海马神经元的影响%Effect of oxymatrine on learning and memory and hippocampus neuron in epileptic rats

    Institute of Scientific and Technical Information of China (English)

    张琳娜; 张丽霞; 白洁

    2012-01-01

    Objective To explore the effects of oxymatrine on learning and memory and the hippocampus neurons in epileptic rats induced by penicillin. Methods Forty-eight SD rats were randomly divided into normal saline( NS ) group, epilepsy( EP ) group, oxymatraine( OXY ) group and phenobarbital sodium( PBS ) group. Penicillin was injected intraperitoneally in rats to establish the epilepsy model. Then behavioral changes were observed. The stay time of rats and the swimming length of rats in regions A and C were observed through Morris water maze video tracking system. The spatial learning and memory was tested by Morris water maze( MWM ). And the changes of hippocampus neuron in rats were observed. Results The stay time of rats and the swimming length of rats in region A in PBS group and OXY group were longer than those in EP group( P < 0. 05 ). The abilities of learning and memory in OXY group were significantly improved. After epilepsy induced by penicillin, the neuron tumefaction and organelle damnification were found. But after using OXY,the neuron tumefaction and organelle damnification were alleviated. Conclusion OXY could protect the spatial learning and memory in epileptic rats.%目的 观察氧化苦参碱(oxymatrine,OXY) 对青霉素(penicillin,PEN) 致痫大鼠学习记忆功能和海马神经元形态的影响.方法 成年SD 大鼠48只随机分为生理盐水对照组(normal saline,NS)、癫痫模型组(epilepsy,EP)、氧化苦参碱组(OXY)和苯巴比妥钠阳性对照组(PBS),腹腔注射青霉素诱导大鼠癫痫发作,观察大鼠行为学改变,Morris 水迷宫检测大鼠空间学习和记忆,观察大鼠海马区神经元细胞形态学改变.结果 通过Morris水迷宫视频跟踪系统观察各组大鼠在A区和C区停留的时间和在A区和C区游泳路径的长度,PBS 组和OXY 组在A区的停留时间和在A区的游泳路径比EP 组明显增长(P<0.05),对大鼠空间记忆能力有所改善.NS组神经细胞结构正常;EP组可见神

  5. The Case for Tetrahedral Oxy-subhydride (TOSH Structures in the Exclusion Zones of Anchored Polar Solvents Including Water

    Directory of Open Access Journals (Sweden)

    Klaus Oehr

    2014-11-01

    Full Text Available We hypothesize a mechanistic model of how negatively-charged exclusion zones (EZs are created. While the growth of EZs is known to be associated with the absorption of ambient photonic energy, the molecular dynamics giving rise to this process need greater elucidation. We believe they arise due to the formation of oxy-subhydride structures (OH−(H2O4 with a tetrahedral (sp3 (OH−(H2O3 core. Five experimental data sets derived by previous researchers were assessed in this regard: (1 water-derived EZ light absorbance at specific infrared wavelengths, (2 EZ negative potential in water and ethanol, (3 maximum EZ light absorbance at 270 nm ultraviolet wavelength, (4 ability of dimethyl sulphoxide but not ether to form an EZ, and (5 transitory nature of melting ice derived EZs. The proposed tetrahedral oxy-subhydride structures (TOSH appear to adequately account for all of the experimental evidence derived from water or other polar solvents.

  6. High-temperature-oxidation-induced ordered structure in Inconel 939 superalloy exposed to oxy-combustion environments

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jingxi; Wise, Adam; Nuhfer, Thomas; Holcomb, Gordon R; Jablonski, Paul D; Sridhar, Seetharaman; Laughlin, David E

    2013-04-20

    In the integrated oxy-fuel combustion and turbine power generation system, turbine alloys are exposed to high temperature and an atmosphere comprised of steam, CO2 and O2. While surface and internal oxidation of the alloy takes place, the microstructure in the subsurface region also changes due to oxidation that results in the loss of the strengthening precipitates. In an earlier study of the oxidation of Inconel 939 Ni-based superalloy exposed to oxy-fuel combustion environment for up to 1000 hours, a high-temperature-oxidation-induced phase transformation in the sub-surface region was noticed and a two-phase region formed at the expense of strengthening γ' phase. While one of the two phases was identified as the Ni-matrix (γ solid solution, face-center-cubic) phase, the other product phase remained unidentified. In this study, the crystal structure of the unknown phase and its orientation relationship with the parent Ni-matrix phase was investigated through electron diffraction and high-resolution transmission electron microscopy. It was determined that the crystal structure of the unknown phase could be modeled as a ternary derivative of the ordered η-Ni3Ti phase (D024) structure with lattice parameters of a = 0.5092 nm and c = 0.8336 nm, α = 90º, β = 90º and γ = 120º.

  7. A Comparative CFD Study on Simulating Flameless Oxy-Fuel Combustion in a Pilot-Scale Furnace

    Directory of Open Access Journals (Sweden)

    Mersedeh Ghadamgahi

    2016-01-01

    Full Text Available The current study presents a method to model the flameless oxy-fuel system, with a comparative approach, as well as validation of the predictions. The validation has been done by comparing the predicted results with previously published experimental results from a 200 kW pilot furnace. A suction pyrometer has been used to measure the local temperature and concentrations of CO, CO2, and O2 at 24 different locations. A three-dimensional CFD model was developed and the validity of using different submodels describing turbulence and chemical reactions was evaluated. The standard k-ε model was compared with the realizable k-ε model for turbulence, while Probability Density Function (PDF with either chemical equilibrium or the Steady Laminar Flamelet Model (SLFM was evaluated for combustion. Radiation was described using a Discrete Ordinates Model (DOM with weighted-sum-of-grey-gases model (WSGGM. The smallest deviation between predictions and experiments for temperature (1.2% was found using the realizable k-ε model and the SLFM. This improvement affects the prediction of gaseous species as well since the deviation between predictions and experiments for CO2 volume percentages decreased from 6% to 1.5%. This provides a recommendation for model selections in further studies on flameless oxy-fuel combustion.

  8. Assessing the Role of Particles in Radiative Heat Transfer during Oxy-Combustion of Coal and Biomass Blends

    Directory of Open Access Journals (Sweden)

    Gautham Krishnamoorthy

    2015-01-01

    Full Text Available This study assesses the required fidelities in modeling particle radiative properties and particle size distributions (PSDs of combusting particles in Computational Fluid Dynamics (CFD investigations of radiative heat transfer during oxy-combustion of coal and biomass blends. Simulations of air and oxy-combustion of coal/biomass blends in a 0.5 MW combustion test facility were carried out and compared against recent measurements of incident radiative fluxes. The prediction variations to the combusting particle radiative properties, particle swelling during devolatilization, scattering phase function, biomass devolatilization models, and the resolution (diameter intervals employed in the fuel PSD were assessed. While the wall incident radiative flux predictions compared reasonably well with the experimental measurements, accounting for the variations in the fuel, char and ash radiative properties were deemed to be important as they strongly influenced the incident radiative fluxes and the temperature predictions in these strongly radiating flames. In addition, particle swelling and the diameter intervals also influenced the incident radiative fluxes primarily by impacting the particle extinction coefficients. This study highlights the necessity for careful selection of particle radiative property, and diameter interval parameters and the need for fuel fragmentation models to adequately predict the fly ash PSD in CFD simulations of coal/biomass combustion.

  9. The different behavior of rutile and anatase nanoparticles in forming oxy radicals upon illumination with visible light: an EPR study.

    Science.gov (United States)

    Lipovsky, Anat; Levitski, Luba; Tzitrinovich, Zeev; Gedanken, Aharon; Lubart, Rachel

    2012-01-01

    Photoexcited TiO(2) has been found to generate reactive oxygen species, yet the precise mechanism and chemical nature of the generated oxy species especially regarding the different crystal phases remain to be elucidated. Visible light-induced reactions of a suspension of titanium dioxide (TiO(2)) in water were investigated using electron paramagnetic resonance (EPR) coupled with the spin-trapping technique. Increased levels of both hydroxyl (˙OH) and superoxide anion (˙O(2)(-)) radicals were detected in TiO(2) rutile and anatase nanoparticles (50 nm). The intensity of signals assigned to the ˙OH and ˙O(2)(-) radicals was larger for the anatase phase than that originating from rutile. Moreover, illumination with visible (nonUV) light enhanced ˙O(2)(-) formation in the rutile phase. Singlet oxygen was not detected in water suspension of TiO(2) neither in rutile nor in anatase nanoparticles, but irradiation of the rutile phase with visible light revealed a signal, which could be attributed to singlet oxygen formation. The blue part of visible spectrum (400-500 nm) was found to be responsible for the light-induced ROS in TiO(2) nanoparticles. The characterization of the mechanism of visible light-induced oxy radicals formation by TiO(2) nanoparticles could contribute to its use as a sterilization agent.

  10. Combustion characteristics and air pollutant formation during oxy-fuel co-combustion of microalgae and lignite.

    Science.gov (United States)

    Gao, Yuan; Tahmasebi, Arash; Dou, Jinxiao; Yu, Jianglong

    2016-05-01

    Oxy-fuel combustion of solid fuels is seen as one of the key technologies for carbon capture to reduce greenhouse gas emissions. The combustion characteristics of lignite coal, Chlorella vulgaris microalgae, and their blends under O2/N2 and O2/CO2 conditions were studied using a Thermogravimetric Analyzer-Mass Spectroscopy (TG-MS). During co-combustion of blends, three distinct peaks were observed and were attributed to C. vulgaris volatiles combustion, combustion of lignite, and combustion of microalgae char. Activation energy during combustion was calculated using iso-conventional method. Increasing the microalgae content in the blend resulted in an increase in activation energy for the blends combustion. The emissions of S- and N-species during blend fuel combustion were also investigated. The addition of microalgae to lignite during air combustion resulted in lower CO2, CO, and NO2 yields but enhanced NO, COS, and SO2 formation. During oxy-fuel co-combustion, the addition of microalgae to lignite enhanced the formation of gaseous species.

  11. ENTHALPY RELAXATIONS AND CONCENTRATION FLUCTUATIONS IN BLENDS OF POLYSTYRENE AND POLY(OXY-2,6-DIMETHYL-1,4-PHENYLENE)

    NARCIS (Netherlands)

    OUDHUIS, AACM; TENBRINKE, G

    1992-01-01

    A series of enthalpy relaxation measurements were carried out for the pure polymers polystyrene (PS) and poly(oxy-2,6-dimethyl-1,4-phenylene) (PPE) and for homogeneous blends thereof. The data were analyzed using Moynihan's four-parameter approach.4 For the pure components the best fit parameter val

  12. 奥施康定治疗中重度癌痛疗效观察%Clinical efficacy of OxyContin in the treatment of cancer pain

    Institute of Scientific and Technical Information of China (English)

    Xiaomei Li; Duanqi Liu

    2007-01-01

    Objective:To evaluate the analgesic efficacy as well as adverse effects of OxyContin for the treatment of moderate to severe cancer pain.Methods:OxyContin was administered at an initial dose of 10 ma every 12 h and titrated upwards according to the extent of pain relief.The analgesic effect,Karnofsky performance status(KPS)scale as well as adverse effects were investigated.Results:The mean onset time and duration of analgesic effect was 41 min and 12.6 h.respectively.with the daily average dose of 69.03mg.Among all the 31 patients who had suffered moderate to severe pain.slight pain relief was achieved in one patient(3.23%).Moderate,obvious and complete pain relief were achieved in 4(12.90%),20 (64.52%)and 6 (19.53%),respectively.KPS was elevated in 19 (61.29%) and stable in 9 (29.03%)patients after administration of OxyContin.3(9.68%)patients were died of disease deterioration.Main adverse effect was constipation in 10 cases(32.26%).Conclusio:OxyContin was effective in the treatment of moderate to severe cancer pain.with rapid onset,good analgesic performance,mild adverse effect and safety profile.

  13. COMPARATIVE ELECTRON-MICROSCOPY AND IMAGE-ANALYSIS OF OXY-HEMOCYANIN AND DEOXY-HEMOCYANIN FROM THE SPINY LOBSTER PANULIRUS-INTERRUPTUS

    NARCIS (Netherlands)

    DEHAAS, F; VANBREEMEN, JFL; BOEKEMA, EJ; KEEGSTRA, W; VANBRUGGEN, EFJ

    1993-01-01

    Structural differences between oxy-hemocyanin and deoxy-hemocyanin from the spiny lobster P. interruptus were studied by electron microscopy and image analysis of negatively stained preparations. Projections of the hexameric P. interruptus hemocyanin from electron microscopy were compared with simul

  14. 40 CFR 721.1730 - Poly(oxy-1,2-ethanediyl), α-butyl-ω-hydroxy, ester with boric acid (H3BO3).

    Science.gov (United States)

    2010-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1730 Section 721.1730 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-butyl-ω-hydroxy, ester with...

  15. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Science.gov (United States)

    2010-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  16. 1-(2,4-Di-nitro-phen-yl)-2-[(E)-(3,4,5-tri-meth-oxy-benzyl-idene)]hydrazine.

    Science.gov (United States)

    Chantrapromma, Suchada; Ruanwas, Pumsak; Boonnak, Nawong; Chidan Kumar, C S; Fun, Hoong-Kun

    2014-02-01

    Mol-ecules of the title compound, C16H16N4O7, are not planar with a dihedral angle of 5.50 (11)° between the substituted benzene rings. The two meta-meth-oxy groups of the 3,4,5-tri-meth-oxy-benzene moiety lie in the plane of the attached ring [Cmeth-yl-O-C-C torsion angles -0.1 (4)° and -3.7 (3)°] while the para-meth-oxy substituent lies out of the plane [Cmeth-yl-O-C-C, -86.0 (3)°]. An intra-molecular N-H⋯O hydrogen bond involving the 2-nitro substituent generates an S(6) ring motif. In the crystal structure, mol-ecules are linked by weak C-H⋯O inter-actions into screw chains, that are arranged into a sheet parallel to the bc plane. These sheets are connected by π-π stacking inter-actions between the nitro and meth-oxy substituted aromatic rings with a centroid-centroid separation of 3.9420 (13) Å. C-H⋯π contacts further stabilize the two-dimensional network.

  17. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  18. Hydrogen peroxide-induced oxidative damage in peripheral blood lymphocytes from rats chronically treated with corticosterone: The protective effect of oxytocin treatment.

    Science.gov (United States)

    Stanić, Dušanka; Plećaš-Solarović, Bosiljka; Petrović, Jelena; Bogavac-Stanojević, Nataša; Sopić, Miron; Kotur-Stevuljević, Jelena; Ignjatović, Svetlana; Pešić, Vesna

    2016-08-25

    Contemporary lifestyle is commonly associated with chronic stress, an environmental factor contributing to development of various psychological and somatic disorders. Increased levels of glucocorticoids, observed in the chronic stress, induce the production of reactive oxygen species leading to genotoxicity. The aim of this study was to investigate whether chronic administration of oxytocin (OXY) 10 IU/400 μL/day, s.c., for 14 days, a hormone presumed to exert antioxidant effect, may prevent DNA damage in the comet assay of peripheral blood lymphocytes of Wistar rats treated chronically with corticosterone (CORT) 100 mg/L ad libitum, per os, for 21 days, as well as, to influence some plasma oxidative stress parameters, i.e. levels of total lipid hydroperoxide (LOOH), and malondialdehyde (MDA), and the activity of antioxidative enzyme superoxide dismutase (SOD). Even though there was no reduction in overall number of damaged cells after oxytocin treatment only, the marked increase in total comet score (TCS) after incubation with H2O2 in CORT group compared to controls, was absent in the CORT + OXY experimental group. Furthermore, significant decrease of highly damaged cells compared to corticosterone group was noted. Chronic oxytocin administration thus protected lymphocytes from high intensity damage that leads to cellular death. In addition, treatment with OXY along with CORT, significantly decreased concentration of LOOH in plasma, and increased SOD compared to CORT treatment only. This finding corresponds well with current reports on beneficial effects of OXY in conditions of HPA axis hyperactivity, and supports the hypothesis of OXY-mediated antioxidant action.

  19. An upstream Hfq binding site in the fhlA mRNA leader region facilitates the OxyS-fhlA interaction.

    Directory of Open Access Journals (Sweden)

    Nilshad N Salim

    Full Text Available BACKGROUND: To survive, bacteria must be able to adapt to environmental stresses. Small regulatory RNAs have been implicated as intermediates in a variety of stress-response pathways allowing dynamic gene regulation. The RNA binding protein Hfq facilitates this process in many cases, helping sRNAs base pair with their target mRNAs and initiate gene regulation. Although Hfq has been identified as a critical component in many RNPs, the manner by which Hfq controls these interactions is not known. METHODOLOGY/PRINCIPAL FINDINGS: To test the requirement of Hfq in these mRNA-sRNA complexes, the OxyS-fhlA system was used as a model. OxyS is induced in response to oxidative stress and down regulates the translation of fhlA, a gene encoding a transcriptional activator for formate metabolism. Biophysical characterization of this system previously used a minimal construct of the fhlA mRNA which inadvertently removed a critical element within the leader sequence of this mRNA that effected thermodynamics and kinetics for the interaction with Hfq. CONCLUSIONS/SIGNIFICANCE: Herein, we report thermodynamic, kinetic and structural mapping studies during binary and ternary complex formation between Hfq, OxyS and fhlA mRNA. Hfq binds fhlA mRNA using both the proximal and distal surfaces and stimulates association kinetics between the sRNA and mRNA but remains bound to fhlA forming a ternary complex. The upstream Hfq binding element within fhlA is similar to (ARN(x elements recently identified in other mRNAs regulated by Hfq. This work leads to a kinetic model for the dynamics of these complexes and the regulation of gene expression by bacterial sRNAs.

  20. Burned after reading: the so-called list of Alexandrian librarians in P. Oxy. X 1241 Brûlée après lecture : la liste dite des Bibliothécaires d'Alexandrie dans le P.Oxy. X 1241 Burned after reading; la cosiddetta lista di bibliotecari alessandrini in P.Oxy. X 1241

    Directory of Open Access Journals (Sweden)

    Jackie Murray

    2012-06-01

    Full Text Available Cet article remet en question la valeur et la fiabilité du contenu du P.Oxy. X 1241, la liste dite des Bibliothécaires d’Alexandrie. Plutôt que de traiter de la liste des grammairiens des colonnes i.5.-ii.30 pour elle-même, comme les savants l’ont fait depuis que le papyrus a été publié, cet article prend en considération le document dans son intégralité. Cette lecture plus attentive du P.Oxy. X 1241 démontre qu’il y a une évidente continuité thématique entre la liste des grammairiens et les catalogues militaires qui suivent, qui n’a jamais été observée précédemment parce que les deux parties du document ont été traitées séparement. Il en découle des questions concernant trois hypothèses essentielles émises par les éditeurs originaux, B. P. Grenfell et A. S. Hunt : (1 la liste des col. i.5-ii.30 est-elle en réalité une liste des Bibliothécaires en chef de la Bibliothèque d’Alexandrie ? (2 le document est-il une copie ou une compilation de quelque œuvre savante qui remonte à la période hellénistique, et non la production d’un savant/grammairien du deuxième siècle de notre ère environ ? (3 Est-ce que les contenus du papyrus reflètent l’œuvre d’un savant/grammairien compétent qui était suffisamment informé sur la chronologie de la période ptolémaïque pour donner un décompte historiquement exact de la succession d’individus liés à la cour des Ptolémées et à la Bibliothèque d’Alexandrie ? S’il est vrai que dans son contenu et son utilisation de citations savantes le P.Oxy. X 1241 partage de nombreux points communs avec les catalogues en prose des époques hellénistique et impériale, les stratégies du discours savant déployées par l’auteur dans le catalogue militaire ne sont pas conformes aux normes des exemples scientifiques fiables. En conséquence, la valeur du texte comme preuve documentaire de l’histoire de la Bibliothèque d’Alexandrie a besoin d

  1. Adsorption Mechanisms of Trivalent Gold onto Iron Oxy-Hydroxides: From the Molecular Scale to the Model

    Energy Technology Data Exchange (ETDEWEB)

    Cances, Benjamin; /Marne La Vallee U.; Benedetti, Marc; /unknown; Farges, Francois; /Museum Natl. Hist. Natur., Paris /Stanford U., Geo. Environ. Sci.; Brown, Gordon E.., Jr.; /Stanford U., Geo. Environ. Sci. /SLAC, SSRL

    2006-12-13

    Gold is a highly valuable metal that can concentrate in iron-rich exogenetic horizons such as laterites. An improved knowledge of the retention mechanisms of gold onto highly reactive soil components such as iron oxyhydroxides is therefore needed to better understand and predict the geochemical behavior of this element. In this study, we use EXAFS information and titration experiments to provide a realistic thermochemical description of the sorption of trivalent gold onto iron oxy-hydroxides. Analysis of Au L{sub III}-edge XAFS spectra shows that aqueous Au(III) adsorbs from chloride solutions onto goethite surfaces as inner-sphere square-planar complexes (Au(III)(OH,Cl){sub 4}), with dominantly OH ligands at pH > 6 and mixed OH/Cl ligands at lower pH values. In combination with these spectroscopic results, Reverse Monte Carlo simulations were used to constraint the possible sorption sites on the surface of goethite. Based on this structural information, we calculated sorption isotherms of Au(III) on Fe oxy-hydroxides surfaces, using the CD-MUSIC (Charge Distribution--Multi Site Complexation) model. The various Au(III)-sorbed species were identified as a function of pH, and the results of these EXAFS+CD-MUSIC models are compared with titration experiments. The overall good agreement between the predicted and measured structural models shows the potential of this combined approach to better model sorption processes of transition elements onto highly reactive solid surfaces such as goethite and ferrihydrite.

  2. Methane coupling reaction in an oxy-steam stream through an OH radical pathway by using supported alkali metal catalysts

    KAUST Repository

    Liang, Yin

    2014-03-24

    A universal reaction mechanism involved in the oxidative coupling of methane (OCM) is demonstrated under oxy-steam conditions using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from a H 2O-O2 reaction followed by C-H activation in CH 4 with an OH radical. Thus, the presence of water enhances both the CH4 conversion rate and the C2 selectivity. This OH radical pathway that is selective for the OCM was observed for the catalyst without Mn, which suggests clearly that Mn is not the essential component in a selective OCM catalyst. The experiments with different catalyst compositions revealed that the OH.-mediated pathway proceeded in the presence of catalysts with different alkali metals (Na, K) and different oxo anions (W, Mo). This difference in catalytic activity for OH radical generation accounts for the different OCM selectivities. As a result, a high C2 yield is achievable by using Na2WO4/SiO2, which catalyzes the OH.-mediated pathway selectively. Make it methane: A universal reaction mechanism involved in the oxidative coupling of methane is demonstrated under oxy-stream conditions by using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from an H2O-O2 reaction, followed by C-H activation in CH4 with an OH radical. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Band offset in zinc oxy-sulfide/cubic-tin sulfide interface from X-ray photoelectron spectroscopy

    Science.gov (United States)

    K. C., Sanal; Nair, P. K.; Nair, M. T. S.

    2017-02-01

    Zinc oxy-sulfide, ZnOxS1-x, has been found to provide better band alignment in thin film solar cells of tin sulfide of orthorhombic crystalline structure. Here we examine ZnOxS1-x/SnS-CUB interface, in which the ZnOxS1-x thin film was deposited by radio frequency (rf) magnetron sputtering on SnS thin film of cubic (CUB) crystalline structure with a band gap (Eg) of 1.72 eV, obtained via chemical deposition. X-ray photoelectron spectroscopy provides the valence band maxima of the materials and hence places the conduction band offset of 0.41 eV for SnS-CUB/ZnO0.27S0.73 and -0.28 eV for SnS-CUB/ZnO0.88S0.12 interfaces. Thin films of ZnOxS1-x with 175-240 nm in thickness were deposited from targets prepared with different ZnO to ZnS molar ratios. With the target of molar ratio of 1:13.4, the thin films are of composition ZnO0.27S0.73 with hexagonal crystalline structure and with that of 1:1.7 ratio, it is ZnO0.88S0.12. The optical band gap of the ZnOxS1-x thin films varies from 2.90 eV to 3.21 eV as the sulfur to zinc ratio in the film increases from 0.12:1 to 0.73:1 as determined from X-ray diffraction patterns. Thus, band offsets sought for absorber materials and zinc oxy-sulfide in solar cells may be achieved through a choice of ZnO:ZnS ratio in the sputtering target.

  4. Preparation of zirconium oxy ion-imprinted particle for the selective separation of trace zirconium ion from water.

    Science.gov (United States)

    Ren, Yueming; Liu, Pingxin; Liu, Xiaoli; Feng, Jing; Fan, Zhuangjun; Luan, Tianzhu

    2014-10-01

    Zr(IV) oxy ion-imprinted particle (Zr-IIP) was prepared using the metal ion imprinting technique in a sol-gel process on the surface of amino-silica. The dosages of zirconium ions as imprinted target, (3-aminopropyl) triethoxysilane (APTES) as a functional monomer and teraethyl orthosilicate (TEOS) as a cross-linker were optimized. The prepared Zr-IIP and Zr(IV) oxy ion non-imprinted particle (Zr-NIP) were characterized. pH effect, binding ability and the selectivity were investigated in detail. The results showed that the Zr-IIP had an excellent binding capacity and selectivity in the water. The equilibrium data fitted well to the pseudo-second-order kinetic and the Langmuir model for Zr(IV) binding onto Zr-IIP, respectively. The saturate binding capacity of Zr-IIP was found to be 196.08 μmol g(-1), which was 18 times higher than that of Zr-NIP. The sequence of binding efficiency of Zr-IIP for various ions was Zr(IV)>Cu(II)>Sb(III)>Eu(III). The coordination number has an important effect on the dimensional binding capacity. The equilibrium binding capacity of Zr-IIP for Zr(IV) decreased little under various concentrations of Pb(II) ions. The analysis of relative selectivity coefficient (Kr) indicated that the Zr-IIP had an appreciable binding specificity towards Zr(IV) although the competitive ions coexisted in the water. The Zr-IIP could serve as an efficient selective material for recovering or removing zirconium from the water environment.

  5. On the potential for BECCS efficiency improvement through heat recovery from both post-combustion and oxy-combustion facilities.

    Science.gov (United States)

    Dowell, N Mac; Fajardy, M

    2016-10-20

    In order to mitigate climate change to no more than 2 °C, it is well understood that it will be necessary to directly remove significant quantities of CO2, with bioenergy CCS (BECCS) regarded as a promising technology. However, BECCS will likely be more costly and less efficient at power generation than conventional CCS. Thus, approaches to improve BECCS performance and reduce costs are of importance to facilitate the deployment of this key technology. In this study, the impact of biomass co-firing rate and biomass moisture content on BECCS efficiency with both post- and oxy-combustion CO2 capture technologies was evaluated. It was found that post-combustion capture BECCS (PCC-BECCS) facilities will be appreciably less efficient than oxy-combustion capture BECCS (OCC-BECCS) facilities. Consequently, PCC-BECCS have the potential to be more carbon negative than OCC-BECCS per unit electricity generated. It was further observed that the biomass moisture content plays an important role in determining the BECCS facilities' efficiency. This will in turn affect the enthalpic content of the BECCS plant exhaust and implies that exhaust gas heat recovery may be an attractive option at higher rates of co-firing. It was found that there is the potential for the recovery of approximately 2.5 GJheat per tCO2 at a temperature of 100 °C from both PCC-BECCS and OCC-BECCS. On- and off-site applications for this recovered heat are discussed, considering boiler feedwater pre-heating, solvent regeneration and district heating cases.

  6. Assisted curation of regulatory interactions and growth conditions of OxyR in E. coli K-12.

    Science.gov (United States)

    Gama-Castro, Socorro; Rinaldi, Fabio; López-Fuentes, Alejandra; Balderas-Martínez, Yalbi Itzel; Clematide, Simon; Ellendorff, Tilia Renate; Santos-Zavaleta, Alberto; Marques-Madeira, Hernani; Collado-Vides, Julio

    2014-01-01

    Given the current explosion of data within original publications generated in the field of genomics, a recognized bottleneck is the transfer of such knowledge into comprehensive databases. We have for years organized knowledge on transcriptional regulation reported in the original literature of Escherichia coli K-12 into RegulonDB (http://regulondb.ccg.unam.mx), our database that is currently supported by >5000 papers. Here, we report a first step towards the automatic biocuration of growth conditions in this corpus. Using the OntoGene text-mining system (http://www.ontogene.org), we extracted and manually validated regulatory interactions and growth conditions in a new approach based on filters that enable the curator to select informative sentences from preprocessed full papers. Based on a set of 48 papers dealing with oxidative stress by OxyR, we were able to retrieve 100% of the OxyR regulatory interactions present in RegulonDB, including the transcription factors and their effect on target genes. Our strategy was designed to extract, as we did, their growth conditions. This result provides a proof of concept for a more direct and efficient curation process, and enables us to define the strategy of the subsequent steps to be implemented for a semi-automatic curation of original literature dealing with regulation of gene expression in bacteria. This project will enhance the efficiency and quality of the curation of knowledge present in the literature of gene regulation, and contribute to a significant increase in the encoding of the regulatory network of E. coli. RegulonDB Database URL: http://regulondb.ccg.unam.mx OntoGene URL: http://www.ontogene.org.

  7. FutureGen 2.0 Oxy-Coal Combustion Carbon Capture Plant Pre-FEED Design and Cost

    Energy Technology Data Exchange (ETDEWEB)

    Flanigan, Tom; Pybus, Craig; Roy, Sonya; Lockwood, Frederick; McDonald, Denny; Maclnnis, Jim

    2011-09-30

    This report summarizes the results of the Pre-Front End Engineering Design (pre-FEED) phase of a proposed advanced oxy-combustion power generation plant to repower the existing 200 MWe Unit 4 at Ameren Energy Resources’ (AER) Meredosia Power Plant. AER has formed an alliance with Air Liquide Process and Construction, Inc. (ALPC) and Babcock & Wilcox Power Generation Group (B&W PGG) for the design, construction, and testing of the facility, and has contracted with URS Corporation (URS) for preliminary design and Owner’s engineering services. The Project employs oxy-combustion technology – combustion of coal with nearly pure oxygen and recycled flue gas (instead of air) – to capture approximately 90% of the flue gas CO2 for transport and sequestration by another Project. Plant capacity and configuration has been developed based on the B&W PGG-ALPC cool recycle process firing high-sulfur bituminous coal fuel, assuming baseload plant operation to maximize existing steam turbine capability, with limited consideration for plant redundancy and performance optimization in order to keep plant costs as low as practical. Activities and preliminary results from the pre-FEED phase addressed in this report include the following: Overall plant thermal performance; Equipment sizing and system configuration; Plant operation and control philosophy; Plant emissions and effluents; CO2 production and recovery characteristics; Project cost estimate and economic evaluation; Integrated project engineering and construction schedule; Project risk and opportunity assessment; Development of Project permitting strategy and requirements During the Phase 2 of the Project, additional design details will be developed and the Phase 1 work products updated to support actual construction and operation of the facility in Phase 3. Additional information will be provided early in Phase 2 to support Ameren-Environmental in finalizing the appropriate permitting strategies and permit

  8. Validation/Uncertainty Quantification for Large Eddy Simulations of the heat flux in the Tangentially Fired Oxy-Coal Alstom Boiler Simulation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.J.; Eddings, E.G.; Ring, T.; Thornock, J.; Draper, T.; Isaac, B.; Rezeai, D.; Toth, P.; Wu, Y.; Kelly, K.

    2014-08-01

    The objective of this task is to produce predictive capability with quantified uncertainty bounds for the heat flux in commercial-scale, tangentially fired, oxy-coal boilers. Validation data came from the Alstom Boiler Simulation Facility (BSF) for tangentially fired, oxy-coal operation. This task brings together experimental data collected under Alstom’s DOE project for measuring oxy-firing performance parameters in the BSF with this University of Utah project for large eddy simulation (LES) and validation/uncertainty quantification (V/UQ). The Utah work includes V/UQ with measurements in the single-burner facility where advanced strategies for O2 injection can be more easily controlled and data more easily obtained. Highlights of the work include: • Simulations of Alstom’s 15 megawatt (MW) BSF, exploring the uncertainty in thermal boundary conditions. A V/UQ analysis showed consistency between experimental results and simulation results, identifying uncertainty bounds on the quantities of interest for this system (Subtask 9.1) • A simulation study of the University of Utah’s oxy-fuel combustor (OFC) focused on heat flux (Subtask 9.2). A V/UQ analysis was used to show consistency between experimental and simulation results. • Measurement of heat flux and temperature with new optical diagnostic techniques and comparison with conventional measurements (Subtask 9.3). Various optical diagnostics systems were created to provide experimental data to the simulation team. The final configuration utilized a mid-wave infrared (MWIR) camera to measure heat flux and temperature, which was synchronized with a high-speed, visible camera to utilize two-color pyrometry to measure temperature and soot concentration. • Collection of heat flux and temperature measurements in the University of Utah’s OFC for use is subtasks 9.2 and 9.3 (Subtask 9.4). Several replicates were carried to better assess the experimental error. Experiments were specifically designed for the

  9. Direct observation of Nd{sup 3+} and Tm{sup 3+} ion distributions in oxy-fluoride glass ceramics containing PbF{sub 2} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jihong [School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); Center for Information Materials, Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Zhao, Zhiyong [State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); Liu, Chao, E-mail: hite@whut.edu.cn [State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); Zhang, Gaoke, E-mail: gkzhang@whut.edu.cn [School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); Zhao, Xiujian [State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, 122 Luoshi Road, Hongshan, Wuhan, Hubei 430070 (China); Heo, Jong [Center for Information Materials, Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Jiang, Yang [China Building Material Institute of Solar-Energy Application, Zhenjiang, Jiangsu 212009 (China)

    2014-12-15

    Nd{sup 3+} and Tm{sup 3+}, doped oxy-fluoride glasses and glass ceramics were prepared by conventional melt-quenching and subsequent heat-treatment, respectively. β-PbF{sub 2} nanocrystals with diameter 50 –100 nm formed in the glass matrix after heat treatment. The Stark splitting in absorption peaks, enhanced photoluminescence and prolonged lifetimes that β-PbF{sub 2} nanocrystal formation increased the luminescence of rare earth ions. Both Nd{sup 3+} and Tm{sup 3+} ions were incorporated into nanocrystals that were enriched in lead and fluorine, and deficient in oxygen. - Highlights: • EELS analysis for rare-earth ion distribution in oxy-fluoride glass ceramics • No significant changes in lifetimes of Nd{sup 3+}, while obvious change for Tm{sup 3+} • Direct evidence of Nd{sup 3+} and Tm{sup 3+} aggregation into fluoride nanocrystals.

  10. Mixed-valence iron minerals on Venus: Fe(2+)-Fe(3+) oxides and oxy-silicates formed by surface-atmosphere interactions

    Science.gov (United States)

    Burns, Roger G.; Straub, Darcy W.

    1992-01-01

    Inferences from these investigations are that Fe(3+)-bearing minerals such as hematite magnesioferrite, acmite, and epidote are thermodynamically unstable, and that magnetite is the predominant mixed-valence iron oxide mineral on venus. Recently, the Fe(2+)-Fe(3+) silicate mineral laihunite was proposed to be a reaction product of olivine with the venusian atmosphere. This possibility is discussed further here. We suggest that other mixed-valence Fe(2+)-Fe(3+)-Oz-OH(-) silicates could also result from surface-atmosphere interactions on Venus. Topics discussed include the following: (1) conversion of hematite to magnetite; (2) stability of laihunite; (3) the possible existence of oxy-amphiboles and oxy-micas on Venus; and (4) other mixed-valence Fe(2+)-Fe(3+) silicates likely to exist on Venus.

  11. Hydrogen peroxide induces protection against lethal effects of cumene hydroperoxide in Escherichia coli cells: an Ahp dependent and OxyR independent system?

    Science.gov (United States)

    Asad, N R; Asad, L M; Silva, A B; Felzenszwalb, I; Leitão, A C

    1998-06-01

    Pretreatment with 2.5 mM H2O2 protects bacterial cells against cumene hydroperoxide killing. This response is independent of the OxyR system, but possibly involves the participation of Ahp protein, since ahp mutants are not protected. Treatment of bacterial cells with high H2O2 concentrations caused an alteration on the electrophoretic profile of the smaller subunit (22-kDa) of Ahp. This alteration does not require novel gene products and is not dependent on the OxyR protein. In this way, we propose that the modification of the 22-kDa subunit of Ahp by high H2O2 concentration may be responsible for the protection against the lethal effects of cumene hydroperoxide.

  12. N-[(9H-Fluoren-9-yl-idene)(2-meth-oxy-phen-yl)meth-yl]-1,1,1-tri-methyl-silanamine.

    Science.gov (United States)

    Li, Zhong-Yuan; Wang, Peng; Chen, Xia

    2014-01-01

    The title mol-ecule, C24H25NOSi, is a hydrolysis product of the reaction between 9-tri-methyl-silyfluorenyl lithium and 2-meth-oxy-benzo-nitrile. The fluorene ring system is substanti-ally planar, with an r.m.s. deviation of 0.0288 Å from the best-fit plane through its 13 C atoms. This plane forms a dihedral angle of 58.07 (7)° with the 2-meth-oxy-benzyl-amine ring plane. In the crystal, mol-ecules are linked by N-H⋯π and C-H⋯π inter-actions, which leads to the formation of two-dimensional network lying parallel to the bc plane.

  13. Tris(2-{[2-(4-meth-oxy-phen-yl)eth-yl]imino-meth-yl}phenolato-κ(2)N,O(1))cobalt(III).

    Science.gov (United States)

    Ourari, Ali; Ouennoughi, Yasmina; Bouacida, Sofiane

    2012-06-01

    In the title compound, [Co(C(16)H(16)NO(2))(3)], the Co(III) atom is six-coordinated in an irregular octa-hedral geometry by three N,O-chelating 2-{[2-(4-meth-oxy-phen-yl)eth-yl]imino-meth-yl}phenolate groups. One of the three meth-oxy group is disordered over two sets of sites with an occupancy ratio of 0.768 (5):0.232 (5). The crystal packing can be described by alternating zigzag layers of organic ligands and CoN(3)O(3) octa-hedra along the c axis. There are no classical hydrogen bonds in the structure, but C-H⋯π inter-actions occur.

  14. Crystal structure of bis-(1,3-di-meth-oxy-imidazolin-2-yl-idene)silver(I) hexa-fluorido-phosphate, N-heterocyclic carbene (NHC) complex.

    Science.gov (United States)

    Rietzler, Barbara; Laus, Gerhard; Kahlenberg, Volker; Schottenberger, Herwig

    2015-12-01

    The title salt, [Ag(C5H8N2O2)2]PF6, was obtained by deprotonation and metalation of 1,3-di-meth-oxy-imidazolium hexa-fluorido-phosphate using silver(I) oxide in methanol. The C-Ag-C angle in the cation is 178.1 (2)°, and the N-C-N angles are 101.1 (4) and 100.5 (4)°. The meth-oxy groups adopt an anti conformation. In the crystal, anions (A) are sandwiched between cations (C) in a layered arrangement {C…A…C} n stacked along [001]. Within a C…A…C layer, the hexafluoridophosphate anions accept several C-H⋯F hydrogen bonds from the cationic complex.

  15. Resolution of galactose, glucose, xylose and mannose in sugarcane bagasse employing a voltammetric electronic tongue formed by metals oxy-hydroxide/MWCNT modified electrodes

    OpenAIRE

    2016-01-01

    Second generation ethanol is produced from the carbohydrates released from the cell wall of bagasse and straw of sugarcane. The objective of this work is the characterization and application of a voltammetric electronic tongue using an array of glassy carbon electrodes modified with multi-walled carbon nanotubes containing metal (Paladium, Gold, Copper, Nickel and Cobalt) oxy-hydroxide nanoparticles (GCE/MWCNT/MetalsOOH) towards a simpler analysis of carbohydrates (glucose, xylose, galactose ...

  16. SYNTHESIS AND CHARACTERIZATION OF LIQUID CRYSTALLINE MULTI-BLOCK COPOLYMERS,POLY[1,6-BIS(4-OXYBENZOYL-OXY)HEXANE TEREPHTHALATE]-b-BISPHENOL A POLYCARBONATE

    Institute of Scientific and Technical Information of China (English)

    Hui-qing Zhang; Xiong-yan Zhao; De-shan Liu; Qi-xiang Zhou

    1999-01-01

    A series of liquid crystalline multi-block copolymers poly[1,6-bis(4-oxybenzoyl-oxy)hexane terephthalate]-b-bisphenol A polycarbonate (PHTH-6-b-PC) with different segment lengths were synthesized in tetrachloroethane by solution polycondensation in which hydroxyl terminated PC and acyl chloride terminated PHTH-6 were used. It is found that block copolymers with high molecular weight and welldefined structures were obtained. All the block copolymers exhibit a nematic liquid crystalline texture.

  17. A comprehensive evaluation of different radiation models in a gas turbine combustor under conditions of oxy-fuel combustion with dry recycle

    Science.gov (United States)

    Kez, V.; Liu, F.; Consalvi, J. L.; Ströhle, J.; Epple, B.

    2016-03-01

    The oxy-fuel combustion is a promising CO2 capture technology from combustion systems. This process is characterized by much higher CO2 concentrations in the combustion system compared to that of the conventional air-fuel combustion. To accurately predict the enhanced thermal radiation in oxy-fuel combustion, it is essential to take into account the non-gray nature of gas radiation. In this study, radiation heat transfer in a 3D model gas turbine combustor under two test cases at 20 atm total pressure was calculated by various non-gray gas radiation models, including the statistical narrow-band (SNB) model, the statistical narrow-band correlated-k (SNBCK) model, the wide-band correlated-k (WBCK) model, the full spectrum correlated-k (FSCK) model, and several weighted sum of gray gases (WSGG) models. Calculations of SNB, SNBCK, and FSCK were conducted using the updated EM2C SNB model parameters. Results of the SNB model are considered as the benchmark solution to evaluate the accuracy of the other models considered. Results of SNBCK and FSCK are in good agreement with the benchmark solution. The WBCK model is less accurate than SNBCK or FSCK. Considering the three formulations of the WBCK model, the multiple gases formulation is the best choice regarding the accuracy and computational cost. The WSGG model with the parameters of Bordbar et al. (2014) [20] is the most accurate of the three investigated WSGG models. Use of the gray WSSG formulation leads to significant deviations from the benchmark data and should not be applied to predict radiation heat transfer in oxy-fuel combustion systems. A best practice to incorporate the state-of-the-art gas radiation models for high accuracy of radiation heat transfer calculations at minimal increase in computational cost in CFD simulation of oxy-fuel combustion systems for pressure path lengths up to about 10 bar m is suggested.

  18. N-(4-Meth-oxy-phen-yl)-6-methyl-2-phenyl-5-{[4-(tri-fluoro-meth-yl)anilino]meth-yl}pyrimidin-4-amine.

    Science.gov (United States)

    Cieplik, Jerzy; Pluta, Janusz; Bryndal, Iwona; Lis, Tadeusz

    2013-11-27

    The title compound, C26H23F3N4O, crystallizes with two symmetry-independent mol-ecules in the asymmetric unit, denoted A and B, which differ mainly in the rotation of the meth-oxy-phenyl ring. The -CF3 group of mol-ecule B is disordered by rotation, with the F atoms split over two sets of sites; the occupancy factor for the major component is 0.853 (4). The dihedral angles between the pyrimidine ring and the attached phenyl, meth-oxy-phenyl and tri-fluoro-methyl-phenyl rings are 8.1 (2), 37.5 (2) and 70.7 (2)°, respectively, in mol-ecule A, and 9.3 (2), 5.3 (2) and 79.7 (2)° in mol-ecule B. An intra-molecular N-H⋯N hydrogen bond occurs in each mol-ecule. In the crystal, two crystallographically independent mol-ecules associate into a dimer via a pair of N-H⋯N hydrogen bonds, with a resulting R 2 (2)(12) ring motif and π-π stacking inter-actions [centroid-centroid distance = 3.517 (4) Å] between the pyrimidine rings. For the A mol-ecules, there are inter-molecular C-H⋯O hydrogen bonds between an aryl C atom of meth-oxy-phenyl ring and a meth-oxy O atom of an adjacent mol-ecule. A similar inter-action is lacking in the B mol-ecules.

  19. Crystal structure of a mixed-ligand dinuclear Ba-Zn complex with 2-meth-oxy-ethanol having tri-phenyl-acetate and chloride bridges.

    Science.gov (United States)

    Utko, Józef; Sobocińska, Maria; Dobrzyńska, Danuta; Lis, Tadeusz

    2015-07-01

    The dinuclear barium-zinc complex, μ-chlorido-1:2κ(2) Cl:Cl-chlorido-2κCl-bis-(2-meth-oxy-ethanol-1κO)bis-(2-meth-oxy-ethanol-1κ(2) O,O')bis-(μ-tri-phenyl-acetato-1:2κ(2) O:O')bariumzinc, [BaZn(C20H15O2)2Cl2(C3H8O2)4], has been synthesized by the reaction of barium tri-phenyl-acetate, anhydrous zinc chloride and 2-meth-oxy-ethanol in the presence of toluene. The barium and zinc metal cations in the dinuclear complex are linked via one chloride anion and carboxyl-ate O atoms of the tri-phenyl-acetate ligands, giving a Ba⋯Zn separation of 3.9335 (11) Å. The irregular nine-coordinate BaO8Cl coordination centres comprise eight O-atom donors, six of them from 2-meth-oxy-ethanol ligands (four from two bidentate O,O'-chelate inter-actions and two from monodentate inter-actions), two from bridging tri-phenyl-acetate ligands and one from a bridging Cl donor. The distorted tetra-hedral coordination sphere of zinc comprises two O-atom donors from the tri-phenyl-acetate ligands and two Cl donors (one bridging and one terminal). In the crystal, O-H⋯Cl, O-H⋯O and C-H⋯Cl inter-molecular inter-actions form a layered structure, lying parallel to (001).

  20. Crystal structure of (E)-13-{4-[(Z)-2-cyano-2-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]phen-yl}parthenolide methanol hemisolvate.

    Science.gov (United States)

    Penthala, Narsimha Reddy; Bommagani, Shobanbabu; Janganati, Venumadhav; Parkin, Sean; Crooks, Peter A

    2014-10-01

    The title compound, C33H35NO6 [systematic name: (Z)-3-(4-{(E)-[(E)-1a,5-dimethyl-9-oxo-2,3,7,7a-tetra-hydro-oxireno[2',3':9,10]cyclo-deca-[1,2-b]furan-8(1aH,6H,9H,10aH,10bH)-yl-idene]meth-yl}phen-yl)-2-(3,4,5-tri-meth-oxy-phen-yl)acrylo-ni-trile methanol hemisolvate], C33H35NO6·0.5CH3OH, was prepared by the reaction of (Z)-3-(4-iodo-phen-yl)-2-(3,4,5-tri-meth-oxy-phen-yl)acrylo-nitrile with parthenolide [systematic name: (E)-1a,5-dimethyl-8-methyl-ene-2,3,6,7,7a,8,10a,10b-octa-hy-dro-oxireno[2',3':9,10]cyclo-deca-[1,2-b]furan-9(1aH)-one] under Heck reaction conditions. The mol-ecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings with a {4-[(Z)-2-cyano-2-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]phen-yl}methyl-idene group as a substituent. The 4-[(Z)-2-cyano-2-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]phenyl group on the parthenolide exocyclic double bond is oriented in a trans position to the lactone ring to form the E isomer. The dihedral angle between the benzene ring of the phenyl moiety and the lactone ring mean plane is 21.93 (4)°.

  1. Tailoring a High Temperature Corrosion Resistant FeNiCrAl for Oxy-Combustion Application by Thermal Spray Coating and HIP

    Directory of Open Access Journals (Sweden)

    Jarkko Metsäjoki

    2015-10-01

    Full Text Available Oxy-fuel combustion combined with CCS (carbon capture and storage aims to decrease CO2 emissions in energy production using fossil fuels. Oxygen firing changes power plant boiler conditions compared to conventional firing. Higher material temperatures and harsher and more variable environmental conditions cause new degradation processes that are inadequately understood at the moment. In this study, an Fe-Ni-Cr-Al alloy was developed based on thermodynamic simulations. The chosen composition was manufactured as powder by gas atomization. The powder was sieved into two fractions: The finer was used to produce thermal spray coatings by high velocity oxy-fuel (HVOF and the coarser to manufacture bulk specimens by hot isostatic pressing (HIP. The high temperature corrosion properties of the manufactured FeNiCrAl coating and bulk material were tested in laboratory conditions simulating oxy-combustion. The manufacturing methods and the results of high temperature corrosion performance are presented. The corrosion performance of the coating was on average between the bulk steel references Sanicro 25 and TP347HFG.

  2. Crystal structures of bis-[(9S,13S,14S)-3-meth-oxy-17-methyl-morphinanium] tetra-chlorido-cobaltate and tetra-chlorido-cuprate.

    Science.gov (United States)

    Gauchat, Eric; Nazarenko, Alexander Y

    2017-01-01

    (9S,13S,14S)-3-Meth-oxy-17-methyl-morphinan (dextromethorphan) forms two isostructural salts with (a) tetra-chlorido-cobaltate, namely bis-[(9S,13S,14S)-3-meth-oxy-17-methyl-morphinanium] tetra-chlorido-cobaltate, (C18H26NO)2[CoCl4], and (b) tetra-chlorido-cuprate, namely bis-[(9S,13S,14S)-3-meth-oxy-17-methyl-morphinanium] tetra-chlorido-cuprate, (C18H26NO)2[CuCl4]. The distorted tetra-hedral anions are located on twofold rotational axes. The dextromethorphan cation can be described as being composed of two ring systems, a tetra-hydro-naphthalene system A+B and a deca-hydro-isoquinolinium subunit C+D, that are nearly perpendicular to one another: the angle between mean planes of the A+B and C+D moieties is 78.8 (1)° for (a) and 79.0 (1)° for (b). Two symmetry-related cations of protonated dextromethorphan are connected to the tetra-chlorido-cobaltate (or tetra-chlorido-cuprate) anions via strong N-H⋯Cl hydrogen bonds, forming neutral ion associates. These associates are packed in the (001) plane with no strong attractive bonding between them. Both compounds are attractive crystalline forms for unambiguous identification of the dextromethorphan and, presumably, of its optical isomer, levomethorphan.

  3. 钠钙玻璃熔窑应慎用全氧燃烧技术%Careful Application of Oxy- fuel Combustion Technique to Soda- lime Glass Furnace

    Institute of Scientific and Technical Information of China (English)

    梁德海

    2011-01-01

    通过对普通空气助燃熔窑和全氧燃烧熔窑的对比分析,指出在国内以火力发电为主的现状下,对熔化率高、熔化能耗低及产品产值不高的普通钠钙玻璃熔窑,采用全氧燃烧技术后不能节能,氮氧化物减排效果不明显,成本也有所提高,目前应慎重选用全氧燃烧技术;对于熔制质量要求高、熔化能耗较大及产品产值高的特种玻璃,采用全氧燃烧技术后节能和NOx减排明显,成本降低,经济效益和社会效益好,可考虑逐步推行全氧燃烧技术.%Through the comparison of common air - fuel combustion with oxy - fuel combustion in glass melting furnaces the author pointed out that under the present situation in China that thermal power generation is the major electrical energy, using oxy - fuel combustion technique in melting soda lime glasses with high melting rate, low energy consumption and low output value cannot save energy and Nox emission reduction is also not obvious. Moreover, the production cost is highly increased. Therefore, using oxy - fuel combustion technique to melting soda - lime glasses should be very cautious. As far as special glasses with strict requirements in melting quality, high energy consumption in melting and high output value are concerned, using oxy - fuel combustion technique will save energy and reduce Nox emission remarkably, and production cost will lower down and economic and social benefits will increase as well. For this reason it can be considered that oxy - fuel combustion technique could be widely used for melting above mentioned special glasses step by step.

  4. Abrasive Wear Behavior of WC Reinforced Ni-BASED Composite Coating Sprayed and Fused by Oxy-Acetylene Flame

    Science.gov (United States)

    Wang, Qun; Chen, Zhenhua; Ding, Zhang Xiong; Chen, Ding

    Microstructure of WC reinforced Ni-based self-fluxing alloy composite coating sprayed and fused by oxy-acetylene flame was investigated by scanning electron microscopy and energy dispersive X-ray Spectrometry, X-ray diffraction, and transmission electron microscopy. The wear performance of the coating was studied by a MLS-225 wet sand rubber wheel abrasive wear tester at various loads and sizes of abrasive particles. Also, the wear resistance of the coating was compared with uncoated ASTM1020 steel. The results indicated that the coating is bonded metallurgically to the substrate and has a homogeneous microstructure composed of both coarse WC and fine carbide and boride grains such as Cr7C3, Cr23C6, and Ni2B which disperse uniformly in the matrix of γ-Ni solid solution and Ni3B. The worn mass loss of the coating and ASTM1020 steel both increased with the load and size of abrasive particles, also, the coating has exhibited excellent abrasive wear resistance compared with ASTM1020 steel.

  5. Bifunctional carbohydrate biopolymers entrapped lipase as catalyst for the two consecutive conversions of α-pinene to oxy-derivatives.

    Science.gov (United States)

    Tudorache, Madalina; Gheorghe, Andreea; Negoi, Alina; Enache, Madalin; Maria, Gabriel-Mihai; Parvulescu, Vasile I

    2016-11-01

    Bifunctional catalysts designed as carbohydrate biopolymers entrapping lipase have been investigated for the biotransformation of a natural compound (α-pinene) to oxy-derivatives. Lipases assisted the epoxidation of α-pinene using H2O2 as oxidation reagent and ethyl acetate as both acetate-supplier and solvent affording α-pinene oxide as the main product. Further, the biopolymer promoted the isomerization of α-pinene oxide to campholenic aldehyde and trans-carenol. In this case, the biopolymers played double roles of the support and also active part of the bifunctional catalyst. Screening of enzymes and their entrapping in a biopolymeric matrix (e.g. Ca-alginate and κ-carrageenan) indicated the lipase extracted from Aspergillus niger as the most efficient. In addition, the presence of biopolymers enhanced the catalytic activity of the immobilized lipase (i.e. 13.39×10(3), 19.76×10(3)and 26.46×10(3) for the free lipase, lipase-carrageenan and lipase-alginate, respectively). The catalysts stability and reusability were confirmed in eight consecutively reaction runs.

  6. Influence of high velocity oxy-fuel parameters on properties of nanostructured TiO2 coatings

    Indian Academy of Sciences (India)

    Maryamossadat Bozorgtabar; Mehdi Salehi; Mohammadreza Rahimipour; Mohammadreza Jafarpour

    2010-12-01

    A liquid fuel high velocity oxy-fuel (HVOF) thermal spray process has been used to deposit TiO2 nanostructured coatings utilizing a commercially available nanopowder as the feedstock. The coatings were characterized by means of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM), respectively. Photocatalytic activity was evaluated as a rate constant of decomposition reaction of methylene blue (MB) determined from the changes of relative concentration of MB with UV irradiation time. The results indicate that the sprayed TiO2 coatings were composed of both TiO2 phases viz. anatase and rutile, with different phase contents and crystallite sizes. A high anatase content of 80% by volume was achieved at 0.00015, fuel-to-oxygen ratio with nanostructure coating by grain size smaller than feedstock powder. Photocatalytic activity evaluation results indicated that all the TiO2 coatings are effective to degradation MB under UV radiation and their activities differ in different spray conditions. It is found that fuel flow rate strongly influenced on phase transformation of anatase to rutile and by optimizing the rate which can promote structural transformation and grain coarsening in coating and improving photocatalytic activity.

  7. Identification of redox-sensitive cysteines in the arabidopsis proteome using OxiTRAQ, a quantitative redox proteomics method

    KAUST Repository

    Liu, Pei

    2014-01-28

    Cellular redox status plays a key role in mediating various physiological and developmental processes often through modulating activities of redox-sensitive proteins. Various stresses trigger over-production of reactive oxygen/nitrogen species which lead to oxidative modifications of redox-sensitive proteins. Identification and characterization of redox-sensitive proteins are important steps toward understanding molecular mechanisms of stress responses. Here, we report a high-throughput quantitative proteomic approach termed OxiTRAQ for identifying proteins whose thiols undergo reversible oxidative modifications in Arabidopsis cells subjected to oxidative stress. In this approach, a biotinylated thiol-reactive reagent is used for differential labeling of reduced and oxidized thiols. The biotin-tagged peptides are affinity purified, labeled with iTRAQ reagents, and analyzed using a paralleled HCD-CID fragmentation mode in an LTQ-Orbitrap. With this approach, we identified 195 cysteine-containing peptides from 179 proteins whose thiols underwent oxidative modifications in Arabidopsis cells following the treatment with hydrogen peroxide. A majority of those redox-sensitive proteins, including several transcription factors, were not identified by previous redox proteomics studies. This approach allows identification of the specific redox-regulated cysteine residues, and offers an effective tool for elucidation of redox proteomes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. A novel ion transport membrane reactor for fundamental investigations of oxygen permeation and oxy-combustion under reactive flow conditions

    KAUST Repository

    Kirchen, Patrick

    2013-01-01

    Ion transport membrane (ITM) reactors present an attractive technology for combined air separation and fuel conversion in applications such as syngas production, oxidative coupling or oxy-combustion, with the promise of lower capital and operating costs, as well higher product selectivities than traditional technologies. The oxygen permeation rate through a given ITM is defined by the membrane temperature and oxygen chemical potential difference across it. Both of these parameters can be strongly influenced by thermochemical reactions occurring in the vicinity of the membrane, though in the literature they are often characterized in terms of the well mixed product stream at the reactor exit. This work presents the development of a novel ITM reactor for the fundamental investigation of the coupling between fuel conversion and oxygen permeation under well defined fluid dynamic and thermodynamic conditions, including provisions for spatially resolved, in-situ investigations. A planar, finite gap stagnation flow reactor with optical and probe access to the reaction zone is used to facilitate in-situ measurements and cross-validation with detailed numerical simulations. Using this novel reactor, baseline measurements are presented to elucidate the impact of the sweep gas fuel (CH4) fraction on the oxygen permeation and fuel conversion. In addition, the difference between well-mixed gas compositions measured at the reactor outlet and those measured in the vicinity of the membrane surface are discussed, demonstrating the unique utility of the reactor. © 2012 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

  9. Physical, thermal, structural and optical absorption studies of vanadyl doped magnesium oxy-chloride bismo-borate glasses

    Directory of Open Access Journals (Sweden)

    M.S. Dahiya

    2015-06-01

    Full Text Available Oxy-chloride bismuth-borate glasses with composition xMgCl2·(30 − xMgO·20Bi2O3·50B2O3 containing 2 mol% doping of V2O5 (x = 12, 15, 20, 25 and 30 are prepared by melt-quenching technique. The structural, thermal and optical behaviors are explained by analyzing the data obtained from density (D, molar volume (Vm, theoretical optical basicity (Λth, differential scanning calorimetry (DSC, FTIR and UV–vis results. A decrease in D and increase in Vm (except for sample MBV3 for which D is maximum on increasing chloride content suggests the formation of non-bridging oxygen atoms. Maximum glass transition temperature (Tg and crystallization temperature (Tx have been observed for sample MBV3. The glass stability (S and stability ratio (S/Tg have been calculated from the values of Tg and Tx and both are having maximum values for sample MBV3. Study of the FTIR spectra in the mid-IR range reveals the presence of both triangular and tetrahedral coordinated boron. The optical studies through UV–vis spectral analysis show non-sharp edge. The optical band gap (Eg is also maximum for sample MBV3.

  10. Study of intramolecular isotope heterogeneity of organic oxy acids in order to detect sophisticated wines and juice drinks

    Directory of Open Access Journals (Sweden)

    Kuzmina Helen

    2014-01-01

    Full Text Available According to International Code of Oenological Practices it is allowed to use acide L(+tartrique for wine acidification, while use of synthetic dihydroxysuccinic acid is forbidden. Today it is impossible to differentiate natural dihydroxysuccinic acid from synthetic one by standard techniques. Even by using very sensitive method of isotope mass spectrometry certain difficulties emerge because total isotope characteristics of carbon of dihydroxysuccinic acid of different nature have the same values. However, isotope characteristics of carbon of intramolecular structural groups of dihydroxysuccinic acid made of different raw materials differ significantly. This allows specifying the nature of dihydroxysuccinic acid that is used for making of wines and juice drinks. In Russia, scientific and research institute of beer brewing and wine-making industry carried out a work for studying isotope characteristics of intramolecular isotope heterogeneity of dihydroxysuccinic acid from different origins in order to identify wines and juice drinks. Isotope characteristics of organic oxy acids from different origins were studied including them obtained by synthetic way and numeric range of value δ13 C,‰ were specified. The obtained results allow performing identification tests of wines and juice drinks to find out the products that contain not specified additives as that allowed for its use in production process.

  11. Development of a Novel Oxygen Supply Process and its Integration with an Oxy-Fuel Coal-Fired Boiler

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-12-31

    BOC, the world's second largest industrial gas company, has developed a novel high temperature sorption based technology referred to as CAR (Cyclic Autothermal Recovery) for oxygen production and supply to oxy-fuel boilers with flue gas recycle. This technology is based on sorption and storage of oxygen in a fixed bed containing mixed ionic and electronic conductor materials. The objective of the proposed work was to construct a CAR PDU that was capable of producing 10-scfm of oxygen, using steam or recycled flue gas as the sweep gas, and install it in the Combustion Test Facility. The unit was designed and fabricated at BOC/The Linde Group, Murray Hill, New Jersey. The unit was then shipped to WRI where the site had been prepared for the unit by installation of air, carbon dioxide, natural gas, nitrogen, computer, electrical and infrastructure systems. Initial experiments with the PDU consisted of flowing air into both sides of the absorption systems and using the air heaters to ramp up the bed temperatures. The two beds were tested individually to operational temperatures up to 900 C in air. The cycling process was tested where gases are flowed alternatively from the top then bottom of the beds. The PDU unit behaved properly with respect to flow, pressure and heat during tests. The PDU was advanced to the point where oxygen production testing could begin and integration to the combustion test facility could occur.

  12. Effects of plant stanol ester consumption on fasting plasma oxy(phyto)sterol concentrations as related to fecal microbiota characteristics.

    Science.gov (United States)

    Baumgartner, Sabine; Mensink, Ronald P; Smet, Els De; Konings, Maurice; Fuentes, Susana; de Vos, Willem M; Plat, Jogchum

    2016-03-03

    Information regarding dietary effects on plasma oxyphytosterol concentrations as well as on the origin of oxyphytosterols is scarce. We hypothesized that plant sterols are oxidized in the intestinal lumen, mediated by microbial activity, followed by uptake into the circulation. To address this hypothesis, we carried out, a randomized, double blind, crossover study in 13 healthy subjects, who consumed for 3 weeks control and plant stanol ester enriched margarines (3.0g/d plant stanols) separated by a 4-week wash-out period. Plasma oxy(phyto)sterols were determined via GC-MS/MS, while microbiota analyses were performed on fecal DNA using a phylogenetic microarray to assess microbial composition and diversity. Plasma plant sterol concentrations did not correlate with plasma oxyphytosterols concentrations at baseline. Plant stanol consumption reduced serum sitosterol and campesterol concentrations (-37% and -38%), respectively (pmicrobiota composition and diversity of the faecal contents were not different between the two periods, we observed significant correlations between several specific bacterial groups and plasma plant sterol, but not with plasma oxyphytosterol concentrations. In conclusion, plant stanol ester consumption reduced serum plant sterol and plasma oxyphytosterol concentrations, while intestinal microbiota composition and diversity were not changed. To definitely answer the effects of microbiota on oxyphytosterol formation, future studies could examine oxyphytosterol concentrations after changing intestinal microbial composition or by measuring intestinal oxyphytosterol formation after providing labelled non-oxidized plant sterols.

  13. OxyR-activated expression of Dps is important for Vibrio cholerae oxidative stress resistance and pathogenesis

    Science.gov (United States)

    Xia, Xiaoyun; Larios-Valencia, Jessie; Liu, Zhi; Xiang, Fu; Kan, Biao; Zhu, Jun

    2017-01-01

    Vibrio cholerae is the causative agent of cholera, a dehydrating diarrheal disease. This Gram-negative pathogen is able to modulate its gene expression in order to combat stresses encountered in both aquatic and host environments, including stress posed by reactive oxygen species (ROS). In order to further the understanding of V. cholerae’s transcriptional response to ROS, we performed an RNA sequencing analysis to determine the transcriptional profile of V. cholerae when exposed to hydrogen hydroperoxide. Of 135 differentially expressed genes, VC0139 was amongst the genes with the largest induction. VC0139 encodes a protein homologous to the DPS (DNA-binding protein from starved cells) protein family, which are widely conserved and are implicated in ROS resistance in other bacteria. Using a promoter reporter assay, we show that during exponential growth, dps is induced by H2O2 in a manner dependent on the ROS-sensing transcriptional regulator, OxyR. Upon entry into stationary phase, the major stationary phase regulator RpoS is required to transcribe dps. Deletion of dps impaired V. cholerae resistance to both inorganic and organic hydroperoxides. Furthermore, we show that Dps is involved in resistance to multiple environmental stresses. Finally, we found that Dps is important for V. cholerae adult mouse colonization, but becomes dispensable in the presence of antioxidants. Taken together, our results suggest that Dps plays vital roles in both V. cholerae stress resistance and pathogenesis. PMID:28151956

  14. Effect of vacuum oxy-nitrocarburizing on the microstructure of tool steels: an experimental and modeling study

    Directory of Open Access Journals (Sweden)

    Nikolova Maria

    2017-01-01

    Full Text Available The thermochemical treatments of tool steels improve the performance of the components with respect to surface hardness, wear and tribological performance as well as corrosion resistance. Compared to the conventional gas ferritic nitrocarburizing process, the original vacuum oxy-nitrocarburizing is a time-, cost-effective and environmentally-friendly gas process. Because of the oxidizing nature of the gas atmosphere, there is no need to perform subsequent post-oxidation.In this study, a vacuum oxynitrocarburizing process was carried out onto four tool steels (AISI H10, H11, H21 and D2 at 570 °C, after hardening and single tempering. The structural analysis of the compound and diffusion layers was performed by optical and electron microscopy, X-ray diffraction and glow discharge optical emission spectrometry (GDOES methods. A largely monophase ε- layer is formed with a carbon accumulation at the substrate adjacent area. The overlaying oxides adjacent to the ε-carbonitride phase contained Fe3O4 (magnetite as a main constituent. A thermodynamic modelling approach was also performed to understand and optimize the process. The “Equilib module” of FactSage software which uses Gibbs energy minimization method, was used to estimate the possible products during vacuum oxynitrocarburising process.

  15. Passivation of Si and a-Si:H surfaces by thin oxide and oxy-nitride layers

    Energy Technology Data Exchange (ETDEWEB)

    Pincik, E. [Institute of Physics of SAS, Dubravska Cesta 9, 845 11 Bratislava (Slovakia)]. E-mail: emil.pincik@savba.sk; Kobayashi, H. [Institute of Scientific and Industrial Research, Osaka University, and CREST, Japan Science and Technology Organizarion, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Rusnak, J. [Institute of Physics of SAS, Dubravska Cesta 9, 845 11 Bratislava (Slovakia); Takahashi, M. [Institute of Scientific and Industrial Research, Osaka University, and CREST, Japan Science and Technology Organizarion, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Brunner, R. [Institute of Physics of SAS, Dubravska Cesta 9, 845 11 Bratislava (Slovakia); Jergel, M. [Institute of Physics of SAS, Dubravska Cesta 9, 845 11 Bratislava (Slovakia); Morales-Acevedo, A. [CINVESTAV-IPN, Electrical Engineering Departmant, Avenida IPN No. 2508, 07360 Mexico, D.F. (Mexico); Ortega, L. [Laboratoire de Cristallographie du CNRS, BP 166, 38042 Grenoble Cedex 09 (France); Kakos, J. [Department of Ceramics, Glass and Cement of FCFT of SUT, Radlinskeho 9, 812 37 Bratislava (Slovakia)

    2006-08-31

    An aim of the contribution is focused predominantly on investigation of electrical interface properties of MIS structures consisting of silicon-based substrates, which were passivated by 1.5-12 nm silicon dioxide, silicon nitride and/or silicon oxy-nitride layers. Substrates of different structural properties were used-crystalline Si (c-Si), amorphous hydrogenated silicon (a-Si:H), and silicon layer deposited by plasma enhanced chemical vapor deposition (PECVD). A stress was laid upon structures prepared on n moderately doped c-Si. The paper presents also changes of structural properties of a-Si:H surface after Ar low energy beam impact. For the first time we are presenting important results concerning utilization of X-ray diffraction with {beta} filter in investigation of a-Si:H cluster structure. Considerable part of the contribution is devoted to investigation of electrical properties of Al/Si{sub 3}N{sub 4}/Si (2-3 nm)/GaAs structures with aim to clarify the particular effect of the ultrathin Si interlayer in the structure. Our observations indicate that the silicon interlayer can act as delta doping of GaAs and/or as quantum well. Therefore, the experimental results are compared and discussed with calculated ones obtained by application of our theoretical description of electron emission of quantum well.

  16. Influence of Processing Parameters on Residual Stress of High Velocity Oxy-Fuel Thermally Sprayed WC-Co-Cr Coating

    Science.gov (United States)

    Gui, M.; Eybel, R.; Asselin, B.; Radhakrishnan, S.; Cerps, J.

    2012-10-01

    Residual stress in high velocity oxy-fuel (HVOF) thermally sprayed WC-10Co-4Cr coating was studied based on design of experiment (DOE) with five factors of oxygen flow, fuel gas hydrogen flow, powder feed rate, stand-off distance, and surface speed of substrate. In each DOE run, the velocity and temperature of in-flight particle in flame, and substrate temperature were measured. Almen-type N strips were coated, and their deflections after coating were used for evaluation of residual stress level in the coating. The residual stress in the coating obtained in all DOE runs is compressive. In the present case of HVOF thermally sprayed coating, the residual stress is determined by three types of stress: peening, quenching, and cooling stress generated during spraying or post spraying. The contribution of each type stress to the final compressive residual stress in the coating depends on material properties of coating and substrate, velocity and temperature of in-flight particle, and substrate temperature. It is found that stand-off distance is the most important factor to affect the final residual stress in the coating, following by two-factor interaction of oxygen flow and hydrogen flow. At low level of stand-off distance, higher velocity of in-flight particle in flame and higher substrate temperature post spraying generate more peening stress and cooling stress, resulting in higher compressive residual stress in the coating.

  17. Crystal structures of (Z)-5-[2-(benzo[b]thio-phen-2-yl)-1-(3,5-di-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole and (Z)-5-[2-(benzo[b]thio-phen-3-yl)-1-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole.

    Science.gov (United States)

    Penthala, Narsimha Reddy; Yadlapalli, Jaishankar K B; Parkin, Sean; Crooks, Peter A

    2016-05-01

    (Z)-5-[2-(Benzo[b]thio-phen-2-yl)-1-(3,5-di-meth-oxy-phen-yl)ethen-yl]-1H-tetrazole methanol monosolvate, C19H16N4O2S·CH3OH, (I), was prepared by the reaction of (Z)-3-(benzo[b]thio-phen-2-yl)-2-(3,5-di-meth-oxy-phen-yl)acrylo-nitrile with tri-butyl-tin azide via a [3 + 2]cyclo-addition azide condensation reaction. The structurally related compound (Z)-5-[2-(benzo[b]thio-phen-3-yl)-1-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]-1H-tetra-zole, C20H18N4O3S, (II), was prepared by the reaction of (Z)-3-(benzo[b]thio-phen-3-yl)-2-(3,4,5-tri-meth-oxy-phen-yl)acrylo-nitrile with tri-butyl-tin azide. Crystals of (I) have two mol-ecules in the asymmetric unit (Z' = 2), whereas crystals of (II) have Z' = 1. The benzo-thio-phene rings in (I) and (II) are almost planar, with r.m.s deviations from the mean plane of 0.0084 and 0.0037 Å in (I) and 0.0084 Å in (II). The tetra-zole rings of (I) and (II) make dihedral angles with the mean planes of the benzo-thio-phene rings of 88.81 (13) and 88.92 (13)° in (I), and 60.94 (6)° in (II). The di-meth-oxy-phenyl and tri-meth-oxy-phenyl rings make dihedral angles with the benzo-thio-phene rings of 23.91 (8) and 24.99 (8)° in (I) and 84.47 (3)° in (II). In both structures, mol-ecules are linked into hydrogen-bonded chains. In (I), these chains involve both tetra-zole and methanol, and are parallel to the b axis. In (II), mol-ecules are linked into chains parallel to the a axis by N-H⋯N hydrogen bonds between adjacent tetra-zole rings.

  18. Increase in oxytocin and vasopressin concentration in the blood outflowing from sella turcica region after superior cervical ganglion stimulation in rat

    Energy Technology Data Exchange (ETDEWEB)

    Lipinska, S.; Orlowska-Majdak, M.; Traczyk, W.Z. [Akademia Medyczna, Lodz (Poland). Katedra Fizjologii

    1996-12-31

    The aim of the study was to investigate whether the stimulation of the superior cervical ganglion influences the oxytocin and vasopressin release into the blood in condition of the of the sella turcica integrity. The experiments were performed on male rats under urethane-chloralose anaesthesia. Four 0.7 ml samples of the blood from the sella turcica region flowing through a tube inserted in the maxillary interna vein were collected in the 30, 35, 60 and 90 min of the experiments. The animals were divided into three groups: 1) control, 2) after the exposition of superior cervical ganglion. 3) after the collection of the 1-st sample of the blood the superior cervical ganglion was electrically stimulated for 30 min with trains of pulses. Vasopressin (AVP) and oxytocin (OXY) were determined in the blood plasma by radioimmunoassay. Stimulation of the superior cervical ganglion evoked an significant increase of AVP and OXY release into the blood. The increase of AVP release occurred after 30 min longer latency than the increase of OXY release. (author). 32 refs, 2 figs.

  19. Crystal structure of (4-meth-oxy-phen-yl)[(4-meth-oxy-phen-yl)phospho-nato]dioxidophosphate(1-) 2-amino-6-benzyl-3-eth-oxy-carbon-yl-4,5,6,7-tetra-hydro-thieno[2,3-c]pyridin-6-ium.

    Science.gov (United States)

    Mague, Joel T; Mohamed, Shaaban K; Akkurt, Mehmet; Younes, Sabry H H; Ahmed, Essam K; Albayati, Mustafa R

    2015-12-01

    The asymmetric unit of the title mol-ecular salt, C17H21N2O2S(+)·C14H15O7P2 (-), comprises two cations and two anions. Each cation features an intra-molecular N-H⋯O hydrogen bond, which closes an S(6) ring; in each case the hydro-pyridine ring adopts a half-chair conformation. In the anions, the dihedral angles between the aromatic rings are 64.1 (2) and 54.9 (2)°. In each case, the diphosphate groups are close to eclipsed [C-P⋯P-C pseudo-torsion angles = 11.6 (2) and -19.3 (2)°]. One of the meth-oxy groups in each anion is disordered over two orientations in a 0.539 (18):0.461 (18) ratio in one anion and 0.82 (2):0.18 (2) in the other. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the components into [100] chains. Numerous C-H⋯O inter-actions cross-link the chains into a three-dimensional network.

  20. (μ2-2-Meth-oxy-ethanol-κ(3) O (1):O (1),O (3))(2-meth-oxy-ethanol-κO (1))tris-(μ2-3,4,5,6-tetra-fluoro-o-phenyl-ene-κ(2) C (1):C (2))trimercury(II).

    Science.gov (United States)

    Castañeda, Raúl; Draguta, Sergiu; Yakovenko, Andrey; Fonari, Marina; Timofeeva, Tatiana

    2014-05-01

    In the title compound, [Hg3(C6F4)3(C3H8O2)2], two O atoms from one 2-meth-oxy-ethanol ligand and one O atom from the second 2-meth-oxy-ethanol ligand coordinate three Hg(II) atoms [Hg-O = 2.765 (7)-2.890 (8) Å] in the trimeric organomercurial Lewis acid (o-C6F4Hg)3. The hy-droxy groups are involved in formation of intra- and inter-molecular O-H⋯O hydrogen bonds; the latter link two mol-ecules into centrosymmetric dimers. An extensive net of weak inter-molecular C-H⋯F inter-actions further consolidates the crystal packing.

  1. Comparing the accuracy of ES-BC, EIS-GS, and ES Oxi on body composition, autonomic nervous system activity, and cardiac output to standardized assessments

    Directory of Open Access Journals (Sweden)

    Lewis JE

    2011-09-01

    Full Text Available John E Lewis1, Stacey L Tannenbaum1, Jinrun Gao3, Angelica B Melillo1, Evan G Long1, Yaima Alonso2, Janet Konefal1, Judi M Woolger2, Susanna Leonard1, Prabjot K Singh1, Lawrence Chen1, Eduard Tiozzo1 1Department of Psychiatry and Behavioral Sciences, 2Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, 3State Farm Insurance, Bloomington, IL, USA Background and purpose: The Electro Sensor Complex (ESC is software that combines three devices using bioelectrical impedance, galvanic skin response, and spectrophotometry: (1 ES-BC (Electro Sensor-Body Composition; LD Technology, Miami, FL to assess body composition, (2 EIS-GS (Electro Interstitial Scan-Galvanic Skin; LD Technology to predict autonomic nervous system activity, and (3 ES Oxi (Electro Sensor Oxi; LD Technology to assess cardiac output. The objective of this study was to compare each to a standardized assessment: ES-BC to dual-energy X-ray absorptiometry (DXA, EIS-GS to heart rate variability, and ES Oxi to BioZ Dx Diagnostic System (BioZ Dx; SonoSite Inc, Bothell, WA. Patients and methods: The study was conducted in two waves. Fifty subjects were assessed for body composition and autonomic nervous system activity. Fifty-one subjects were assessed for cardiac output. Results: We found adequate relative and absolute agreement between ES-BC and DXA for fat mass (r = 0.97, P < 0.001 with ES-BC overestimating fat mass by 0.1 kg and for body fat percentage (r = 0.92, P < 0.001 with overestimation of fat percentage by 0.4%. For autonomic nervous system activity, we found marginal relative agreement between EIS-GS and heart rate variability by using EIS-GS as the predictor in a linear regression equation (adjusted R2 = 0.56, P = 0.03. For cardiac output, adequate relative and absolute agreement was found between ES Oxi and BioZ Dx at baseline (r = 0.60, P < 0.001, after the first exercise stage (r = 0.79, P < 0.001, and after the second exercise stage (r = 0.86, P

  2. Development of wear resistant nanostructured duplex coatings by high velocity oxy-fuel process for use in oil sands industry.

    Science.gov (United States)

    Saha, Gobinda C; Khan, Tahir I; Glenesk, Larry B

    2009-07-01

    Oil sands deposits in Northern Alberta, Canada represent a wealth of resources attracting huge capital investment and significant research focus in recent years. As of 2005, crude oil production from the current oil sands operators accounted for 50% of Canada's domestic production. Alberta's oil sands deposits contain approximately 1.7 trillion barrels of bitumen, of which over 175 billion are recoverable with current technology, and 315 billion barrels are ultimately recoverable with technological advances. A major problem of operating machinery and equipment in the oil sands is the unpredictable failure from operating in this highly aggressive environment. One of the significant causes of that problem is premature material wear. An approach to minimize this wear is the use of protective coatings and, in particular, a cermet thin coating. A high level of coating homogeneity is critical for components such as bucketwheels, draglines, conveyors, shovels, heavyhauler trucks etc. that are subjected to severe degradation through abrasive wear. The identification, development and application of optimum wear solutions for these components pose an ongoing challenge. Nanostructured cermet coatings have shown the best results of achieving the degree of homogeneity required for these applications. In this study, WC-17Co cermet powder with nanocrystalline WC core encapsulated with 'duplex' Co layer was used to obtain a nanostructured coating. To apply this coating, high velocity oxy-fuel (HVOF) thermal spraying technique was used, as it is known for producing wear-resistant coatings superior to those obtained from plasma-based techniques. Mechanical, sliding wear and microstructural behavior of the coating was compared with those of the microstructured coating obtained from spraying WC-10Co-4Cr cermet powder by HVOF technique. Results from the nanostructured coating, among others, showed an average of 25% increase in microhardness, 30% increase in sliding wear resistance and

  3. Elucidating the mechanism of Cr(VI) formation upon the interaction with metal oxides during coal oxy-fuel combustion.

    Science.gov (United States)

    Chen, Juan; Jiao, Facun; Zhang, Lian; Yao, Hong; Ninomiya, Yoshihiko

    2013-10-15

    The thermodynamics underpinning the interaction of Cr-bearing species with basic metal oxides, i.e. K2O, Fe2O3, MgO and CaO, during the air and oxy-fuel combustion of coal have been examined. The synchrotron-based X-ray adsorption near-edge spectroscopy (XANES) was used for Cr speciation. For the oxides tested, Cr(VI) formation is dominated by the reduction potential of the metals. The oxides of Ca(2+) with high reduction potential favored the oxidation of Cr(III), same for K(+). The other two basic metals, Fe2O3 and MgO with lower reduction potentials reacted with Cr(III) to form the corresponding chromites at the temperatures above 600°C. Coal combustion experiments in drop-tube furnace have confirmed the rapid capture of Cr vapors, either trivalent or hexavalent, by CaO into solid ash. The existence of HCl in flue gas favored the vaporization of Cr as CrO2Cl2, which was in turn captured by CaO into chromate. Both Fe2O3 and MgO exhibited less capability on scavenging the Cr(VI) vapor. Particularly, MgO alone exhibited a low capability for capturing the vaporized Cr(III) vapors. However, its co-existence with CaO in the furnace inhibited the Cr(VI) formation. This is beneficial for minimizing the toxicity of Cr in the coal combustion-derived fly ash.

  4. A review of recent developments in carbon capture utilizing oxy-fuel combustion in conventional and ion transport membrane systems

    Energy Technology Data Exchange (ETDEWEB)

    Habib, M.A.; Badr, H.M.; Ahmed, S.F. (and others) [King Fahd University of Petrology & Minerals, Dhahran (Saudi Arabia)

    2011-07-15

    Among the proposed methods of CO{sub 2} capture, oxyfuel combustion technology provides a promising option, which is applicable to power generation systems. This technology is based on combustion with pure oxygen (O{sub 2}) instead of air, resulting in flue gas that consists mainly of CO{sub 2} and water (H{sub 2}O), that latter can be separated easily via condensation, while removing other contaminants leaving pure CO{sub 2} for storage. However, fuel combustion in pure O{sub 2} results in intolerably high combustion temperatures. In order to provide the dilution effect of the absent nitrogen (N-2) and to moderate the furnace/combustor temperatures, part of the flue gas is recycled back into the combustion chamber. An efficient source of O{sub 2} is required to make oxycombustion a competitive CO{sub 2} capture technology. Conventional O{sub 2} production utilizing the cryogenic distillation process is energetically expensive. Ceramic membranes made from mixed ion-electronic conducting oxides have received increasing attention because of their potential to mitigate the cost of O{sub 2} production, thus helping to promote these clean energy technologies. Some effort has also been expended in using these membranes to improve the performance of the O{sub 2} separation processes by combining air separation and high-temperature oxidation into a single chamber. This paper provides a review of the performance of combustors utilizing oxy-fuel combustion process, materials utilized in ion-transport membranes and the integration of such reactors in power cycles. The review is focused on carbon capture potential, developments of oxyfuel applications and O{sub 2} separation and combustion in membrane reactors. The recent developments in oxyfuel power cycles are discussed focusing on the main concepts of manipulating exergy flows within each cycle and the reported thermal efficiencies.

  5. The structure of Er3+-doped oxy-fluoride transparent glass-ceramics studied by Raman scattering

    Science.gov (United States)

    Tikhomirov, V. K.; Seddon, A. B.; Ferrari, M.; Montagna, M.; Santos, L. F.; Almeida, R. M.

    2003-11-01

    We show that the structure of transparent oxy-fluoride glass-ceramics formed by heat treatment of glasses of typical composition 32(SiO2):9(AlO1.5):31.5(CdF2):18.5(PbF2): 5.5(ZnF2):3.5(ErF3) mol% consists of ~ 12 nm diameter, Er3+-doped, β-PbF2 nano-crystals embedded in a silica-based glass network and connected to it via non-bridging O and F anions, or fluorine linkages such as Pb-F-Cd and Pb-F-Zn. It is proposed that the glass network structure is mostly chain-like and dominated by Si(O,F)4 tetrahedra with two bridging O and two non-bridging O and/or F atoms (Q2 units). SiO4 tetrahedra with zero and one bridging O (Q0 and Q1 units, respectively) are also present in the glass structure, in the approximate proportion Q0:Q1:Q2 = 1:1:3, a characteristic which appears to be of primary importance. The flexible, chain-like glass-network, with many broken bonds, results in easy accommodation of the Er3+-doped PbF2 nano-crystals, which are grown by heat-treatment of the precursor glass. The boson peak in the Raman spectrum of the precursor glass decreases in intensity upon ceramming and is partly converted to narrow crystalline peaks at lower frequency, consistent with the precipitation of PbF2 crystalline nano-particles. It is suggested that the boson peak involves localized vibrations of broken or stretched Pb-F bonds. The mean free path for these vibrations increases with ceramming, which involves partial crystallization of the glass network, resulting in a shift of the boson peak vibrations to lower-frequency crystalline peaks.

  6. [Properties of 2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5'- phosphate reductase, a enzyme of the second stage of flavinogenesis in Pichia guilliermondii yeasts].

    Science.gov (United States)

    Logvinenko, E M; Shavlovskiĭ, G M; Zakal'skiĭ, A E; Kontorovskaia, N Iu

    1989-01-01

    2,5-Diamino-4-oxy-6-ribosylaminopyrimidine-5'-phosphate reductase has been isolated from cells of Pichia guilliermondii and subjected to 20-fold purification by treating extracts with streptomycin sulphate, frationating proteins (NH4)2SO4 at 45-75% of saturation and chromatography on blue sepharose CL-6B. The use of gel filtration through Sephadex G-150 and chromatography on DEAE-cellulose proved to be less effective for the enzyme purification. It has been established that it is 2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5-phosphate but not its dephosphorylated form that is the substrate of the given reductase; Km is equal to 7.10(-5) M. The reaction proceeds in the presence of NADPH or NADH. The enzyme affinity to NADPH (Km = 4.7.10(-5) M) is approximately one order higher than that to NADPH (Km = 5.5.10(-4) M). The enzyme manifests the optimum of action at pH 7.2 and the temperature of 37 degrees C; the molecular weight is 140 kD. EDTA as well as flavins in the concentration of 1.10(-3) M exert no effect on the reductase activity. The enzyme is labile at 4 degrees C and is inactivated in the frozen state at -15 degrees C. The 2.5-diamino-4-oxy-6-ribosylaminopyrimidine-5'-phosphate reductase has been also revealed in Torulopsis candida, Debaryomyces klöckeri, Schwanniomyces occidentalis, Eremothecium ashbyii (flavinogenic species) and Candida utilis. Aspergillus nidulans, Neurospora crassa (nonflavinogenic species). The synthesis of this enzyme contrary to other enzymes of the riboflavin biosynthesis is not regulated in flavinogenic yeast by iron ions.

  7. Asymmetric Synthesis of (3R, 5R)-3-((tert-Butyldimethylsily)oxy)-5-((Z)-2-Bromovinyl)-Tetrahydro-Furan-2-one, an Intermediate for the Synthesis of Fostriecin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    (3R,5R)-3-((tert-Butyldimethylsily)oxy)-5-((Z)-2-bromovinyl)-tetrahydro-furan-2-one, an intermediate for the synthesis of Fostriecin was achieved by intramolecular asymmetric induction in propene addition of (-)-8-phenylmenthyl glyoxylate followed by inversion of C3-hydroxyl group and Sharpless asymmetric dihydroxylation with simultaneous cyclization to give lactone 5. Then protection of C3-hydroxyl group and oxidation of the C6-primary hydroxyl group which reacted with Wittig reagent to yield the target compound 4.

  8. Bis(6-meth-oxy-2-{[tris-(hydroxy-meth-yl)methyl-κO]imino-meth-yl}phenolato-κN,O)nickel(II) dihydrate.

    Science.gov (United States)

    Zhou, Tian; Zhou, Ru-Jin; An, Zhe

    2009-06-17

    In the title compound, [Ni(C(12)H(16)NO(5))(2)]·2H(2)O, the Ni(II) atom is coordinated by four O atoms and two N atoms from the two 6-meth-oxy-2-{[tris-(hydroxy-meth-yl)meth-yl]imino-meth-yl}phenolate ligands in a distorted octa-hedral coordination geometry. O-H⋯O hydrogen bonds link the complexes and uncoordinated water mol-ecules into two-dimensional networks parallel to (001).

  9. Caractérisation des oxy-hydroxydes de fer et des éléments associés (S, Se, As, Mo, V, Zr) dans les environnements redox favorables aux gisements d’uranium

    OpenAIRE

    Pons, Tony

    2015-01-01

    This work presents a multi-scale and a multi-technical study for the characterization of iron oxi-hydroxides in three uranium-type deposits and host rock. The choice of sites has focused on a roll front deposit: Zoovch Ovoo in a Cretaceous basin of East Gobi (Mongolia); a tectonic-lithological type: Akola/Ebba in Tim Mersoï basin (Niger) and a Proterozoic unconformity type: Kiggavik in Thelon basin (Canada). A new approach has been implemented to characterize the iron oxi-hydroxides on macros...

  10. Chemical Force Spectroscopy Evidence Supporting the Layer-by-Layer Model of Organic Matter Binding to Iron (oxy)Hydroxide Mineral Surfaces

    KAUST Repository

    Chassé, Alexander W.

    2015-08-18

    © 2015 American Chemical Society. The adsorption of dissolved organic matter (DOM) to metal (oxy)hydroxide mineral surfaces is a critical step for C sequestration in soils. Although equilibrium studies have described some of the factors controlling this process, the molecular-scale description of the adsorption process has been more limited. Chemical force spectroscopy revealed differing adhesion strengths of DOM extracted from three soils and a reference peat soil material to an iron (oxy)hydroxide mineral surface. The DOM was characterized using ultrahigh-resolution negative ion mode electrospray ionization Fourier Transform ion cyclotron resonance mass spectrometry. The results indicate that carboxyl-rich aromatic and N-containing aliphatic molecules of DOM are correlated with high adhesion forces. Increasing molecular mass was shown to decrease the adhesion force between the mineral surface and the DOM. Kendrick mass defect analysis suggests that mechanisms involving two carboxyl groups result in the most stable bond to the mineral surface. We conceptualize these results using a layer-by-layer "onion" model of organic matter stabilization on soil mineral surfaces.

  11. Crystal structure of a 2:1 co-crystal of meloxicam with acetyl­endi­carb­oxy­lic acid

    Science.gov (United States)

    Tantardini, Christian; Arkhipov, Sergey G.; Cherkashina, Ksenya A.; Kil’met’ev, Alexander S.; Boldyreva, Elena V.

    2016-01-01

    The pharmaceutical 2:1 co-crystal of meloxicam [MXM; systematic name: 4-hy­droxy-2-methyl-N-(5-methyl­thia­zol-2-yl)-2H-1,2-benzo­thia­zine-3-carboxamide 1,1-dioxide] with acetyl­enedi­carb­oxy­lic acid (ACA; systematic name: but-2-ynedioic acid), crystallizes with one MXM mol­ecule and half an ACA mol­ecule in the asymmetric unit, C14H13N3O4S2·0.5C4H2O4. The mid-point of the triple bond of ACA is located on an inversion centre. In the crystal, the two stereoisomers of MXM with respect to the N atom of the sulfonamide group are related by the inversion centre. The carbonyl and hy­droxy groups belonging to the MXM mol­ecule are involved in an intra­molecular O—H⋯O hydrogen bond. The structure-forming motif includes two MXM mol­ecules linked via an ACA conformer through N—H⋯O and O—H⋯N hydrogen bonds, similar to MXM co-crystals with other di­carb­oxy­lic acids. PMID:27980849

  12. Near-Zero Emissions Oxy-Combustion Flue Gas Purification Task 2: SOx/Nox/Hg Removal for High Sulfur Coal

    Energy Technology Data Exchange (ETDEWEB)

    Nick Degenstein; Minish Shah; Doughlas Louie

    2012-05-01

    The goal of this project is to develop a near-zero emissions flue gas purification technology for existing PC (pulverized coal) power plants that are retrofitted with oxy-combustion technology. The objective of Task 2 of this project was to evaluate an alternative method of SOx, NOx and Hg removal from flue gas produced by burning high sulfur coal in oxy-combustion power plants. The goal of the program was not only to investigate a new method of flue gas purification but also to produce useful acid byproduct streams as an alternative to using a traditional FGD and SCR for flue gas processing. During the project two main constraints were identified that limit the ability of the process to achieve project goals. 1) Due to boiler island corrosion issues >60% of the sulfur must be removed in the boiler island with the use of an FGD. 2) A suitable method could not be found to remove NOx from the concentrated sulfuric acid product, which limits sale-ability of the acid, as well as the NOx removal efficiency of the process. Given the complexity and safety issues inherent in the cycle it is concluded that the acid product would not be directly saleable and, in this case, other flue gas purification schemes are better suited for SOx/NOx/Hg control when burning high sulfur coal, e.g. this project's Task 3 process or a traditional FGD and SCR.

  13. Chemical Force Spectroscopy Evidence Supporting the Layer-by-Layer Model of Organic Matter Binding to Iron (oxy)Hydroxide Mineral Surfaces.

    Science.gov (United States)

    Chassé, Alexander W; Ohno, Tsutomu; Higgins, Steven R; Amirbahman, Aria; Yildirim, Nadir; Parr, Thomas B

    2015-08-18

    The adsorption of dissolved organic matter (DOM) to metal (oxy)hydroxide mineral surfaces is a critical step for C sequestration in soils. Although equilibrium studies have described some of the factors controlling this process, the molecular-scale description of the adsorption process has been more limited. Chemical force spectroscopy revealed differing adhesion strengths of DOM extracted from three soils and a reference peat soil material to an iron (oxy)hydroxide mineral surface. The DOM was characterized using ultrahigh-resolution negative ion mode electrospray ionization Fourier Transform ion cyclotron resonance mass spectrometry. The results indicate that carboxyl-rich aromatic and N-containing aliphatic molecules of DOM are correlated with high adhesion forces. Increasing molecular mass was shown to decrease the adhesion force between the mineral surface and the DOM. Kendrick mass defect analysis suggests that mechanisms involving two carboxyl groups result in the most stable bond to the mineral surface. We conceptualize these results using a layer-by-layer "onion" model of organic matter stabilization on soil mineral surfaces.

  14. Crystal structure of benzyl (E)-2-(3,4-di-meth-oxy-benzyl-idene)hydrazine-1-carbodi-thio-ate.

    Science.gov (United States)

    Tan, Yew-Fung; Break, Mohammed Khaled Bin; Tahir, M Ibrahim M; Khoo, Teng-Jin

    2015-02-01

    The title compound, C17H18N2O2S2, synthesized via a condensation reaction between S-benzyl di-thio-carbazate and 3,4-di-meth-oxy-benzaldehyde, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. Both mol-ecules have an L-shape but differ in the orientation of the benzyl ring with respect to the 3,4-di-meth-oxy-benzyl-idine ring, this dihedral angle is 65.59 (8)° in mol-ecule A and 73.10 (8)° in mol-ecule B. In the crystal, the A and B mol-ecules are linked via pairs of N-H⋯S hydrogen bonds, forming dimers with an R 2 (2)(8) ring motif. The dimers are linked via pairs of C-H⋯O hydrogen bonds, giving inversion dimers of dimers. These units are linked by C-H⋯π inter-actions, forming ribbons propagating in the [100] direction.

  15. Genome-wide Reconstruction of OxyR and SoxRS Transcriptional Regulatory Networks under Oxidative Stress in Escherichia coli K-12 MG1655

    Directory of Open Access Journals (Sweden)

    Sang Woo Seo

    2015-08-01

    Full Text Available Three transcription factors (TFs, OxyR, SoxR, and SoxS, play a critical role in transcriptional regulation of the defense system for oxidative stress in bacteria. However, their full genome-wide regulatory potential is unknown. Here, we perform a genome-scale reconstruction of the OxyR, SoxR, and SoxS regulons in Escherichia coli K-12 MG1655. Integrative data analysis reveals that a total of 68 genes in 51 transcription units (TUs belong to these regulons. Among them, 48 genes showed more than 2-fold changes in expression level under single-TF-knockout conditions. This reconstruction expands the genome-wide roles of these factors to include direct activation of genes related to amino acid biosynthesis (methionine and aromatic amino acids, cell wall synthesis (lipid A biosynthesis and peptidoglycan growth, and divalent metal ion transport (Mn2+, Zn2+, and Mg2+. Investigating the co-regulation of these genes with other stress-response TFs reveals that they are independently regulated by stress-specific TFs.

  16. Accelerated senescence prone mouse-8 shows early onset of deficits in spatial learning and memory in the radial six-arm water maze.

    Science.gov (United States)

    Chen, Gui-Hai; Wang, Yue-Ju; Wang, Xiao-Min; Zhou, Jiang-Ning

    2004-10-15

    Available data indicate that the senescence-accelerated prone mouse 8 (SAMP8) is an appropriate model of brain aging, with impairments in nonspatial learning and memory beginning as early as 2 months of age, and spatial learning and memory deficiencies not becoming apparent until after 4 months of age. However, with other strains (e.g., C57BL mice), the impairment in spatial memory was found earlier than that in nonspatial memory. We considered the possibility that the observed differences could be due to strain-specific differences in the training equipment. In the present study, a new optimized testing apparatus-the radial six-arm water maze (RAWM)-for detecting spatial learning and memory in mice, was employed, to determine whether there is impairment of spatial learning and memory in young SAMP8. The relationship between the spatial learning measures observed with the RAWM and the Morris maze, a classic spatial learning and memory testing apparatus, was also explored. It was found that, in the RAWM, rather than in the Morris maze, the impairment in spatial learning could be measured in SAMP8 mice as early as 3 months old, and the impairment in spatial memory in SAMP8 mice aged 5 months. These results suggested that the spatial learning and memory deficiencies could be found in early life of SAMP8 mice, and that RAWM and Morris maze each detect different aspects of spatial learning and memory.

  17. Sp100 as a potent tumor suppressor: accelerated senescence and rapid malignant transformation of human fibroblasts through modulation of an embryonic stem cell program.

    Science.gov (United States)

    Negorev, Dmitri G; Vladimirova, Olga V; Kossenkov, Andrew V; Nikonova, Elena V; Demarest, Renee M; Capobianco, Anthony J; Showe, Michael K; Rauscher, Frank J; Showe, Louise C; Maul, Gerd G

    2010-12-01

    Identifying the functions of proteins, which associate with specific subnuclear structures, is critical to understanding eukaryotic nuclear dynamics. Sp100 is a prototypical protein of ND10/PML nuclear bodies, which colocalizes with Daxx and the proto-oncogenic PML. Sp100 isoforms contain SAND, PHD, Bromo, and HMG domains and are highly sumoylated, all characteristics suggestive of a role in chromatin-mediated gene regulation. A role for Sp100 in oncogenesis has not been defined previously. Using selective Sp100 isoform-knockdown approaches, we show that normal human diploid fibroblasts with reduced Sp100 levels rapidly senesce. Subsequently, small rapidly dividing Sp100 minus cells emerge from the senescing fibroblasts and are found to be highly tumorigenic in nude mice. The derivation of these tumorigenic cells from the parental fibroblasts is confirmed by microsatellite analysis. The small rapidly dividing Sp100 minus cells now also lack ND10/PML bodies, and exhibit genomic instability and p53 cytoplasmic sequestration. They have also activated MYC, RAS, and TERT pathways and express mesenchymal to epithelial transdifferentiation (MET) markers. Reintroduction of expression of only the Sp100A isoform is sufficient to maintain senescence and to inhibit emergence of the highly tumorigenic cells. Global transcriptome studies, quantitative PCR, and protein studies, as well as immunolocalization studies during the course of the transformation, reveal that a transient expression of stem cell markers precedes the malignant transformation. These results identify a role for Sp100 as a tumor suppressor in addition to its role in maintaining ND10/PML bodies and in the epigenetic regulation of gene expression.

  18. Copper isotope fractionation during its interaction with soil and aquatic microorganisms and metal oxy(hydr)oxides: Possible structural control

    Science.gov (United States)

    Pokrovsky, O. S.; Viers, J.; Emnova, E. E.; Kompantseva, E. I.; Freydier, R.

    2008-04-01

    This work is aimed at quantifying the main environmental factors controlling isotope fractionation of Cu during its adsorption from aqueous solutions onto common organic (bacteria, algae) and inorganic (oxy(hydr)oxide) surfaces. Adsorption of Cu on aerobic rhizospheric ( Pseudomonas aureofaciens CNMN PsB-03) and phototrophic aquatic ( Rhodobacter sp. f-7bl, Gloeocapsa sp. f-6gl) bacteria, uptake of Cu by marine ( Skeletonema costatum) and freshwater ( Navicula minima, Achnanthidium minutissimum and Melosira varians) diatoms, and Cu adsorption onto goethite (FeOOH) and gibbsite (AlOOH) were studied using a batch reaction as a function of pH, copper concentration in solution and time of exposure. Stable isotopes of copper in selected filtrates were measured using Neptune multicollector ICP-MS. Irreversible incorporation of Cu in cultured diatom cells at pH 7.5-8.0 did not produce any isotopic shift between the cell and solution (Δ 65/63Cu(solid-solution)) within ±0.2‰. Accordingly, no systematic variation was observed during Cu adsorption on anoxygenic phototrophic bacteria ( Rhodobacter sp.), cyanobacteria ( Gloeocapsa sp.) or soil aerobic exopolysaccharide (EPS)-producing bacteria ( P. aureofaciens) in circumneutral pH (4-6.5) and various exposure times (3 min to 48 h): Δ 65Cu(solid-solution) = 0.0 ± 0.4‰. In contrast, when Cu was adsorbed at pH 1.8-3.5 on the cell surface of soil the bacterium P. aureofacienshaving abundant or poor EPS depending on medium composition, yielded a significant enrichment of the cell surface in the light isotope (Δ 65Cu (solid-solution) = -1.2 ± 0.5‰). Inorganic reactions of Cu adsorption at pH 4-6 produced the opposite isotopic offset: enrichment of the oxy(hydr)oxide surface in the heavy isotope with Δ 65Cu(solid-solution) equals 1.0 ± 0.25‰ and 0.78 ± 0.2‰ for gibbsite and goethite, respectively. The last result corroborates the recent works of Mathur et al. [Mathur R., Ruiz J., Titley S., Liermann L., Buss H. and

  19. Oxygen reduction reaction (ORR) on mixed oxy-nitride non-noble catalyst: Ab-initio simulation, elaboration and characterization

    Science.gov (United States)

    Seifitokaldani, Ali

    In this project, titanium oxy-nitride (TiOxN y) has been studied as a new non-noble electrocatalyst for the oxygen reduction reaction (ORR). A comprehensive comparison between four different sol-gel methods was carried out to evaluate the physicochemical and electrochemical properties of the produced electro-catalysts. Among them, a new urea-based sol-gel method (simply called U method) is introduced to prepare TiOxNy at a fairly low temperature and duration, with higher electro-catalytic activity for the ORR. The prepared electro-catalysts with different N/O ratios showed different properties from a less conductive behavior in oxygen-rich (low N/O ratio) materials to more conductive electro-catalyst behavior in nitrogen-rich (high N/O ratio) oxy-nitrides, respectively. Generally, electro-catalysts prepared by the U method had more titanium nitride in their structures than the electro-catalysts prepared by the other methods. Nevertheless, heat treatment had a key role in this phase transferring from having high oxide structure to high nitride structure. According to the elemental analysis done by energy dispersive spectroscopy (EDS), nitrogen percentage in the bulk material increased from 9 to 24 percent by increasing the temperature from 700 to 1100 °C, while the oxygen percentage was decreasing inversely. In addition, based on the X-ray diffraction (XRD) data, in the case of U method, the TiN characteristic peaks were obvious, even at lower temperatures. Increasing the temperature also made the peaks much sharper indicating the growth of the crystallite size. The calculated crystallite size showed the crystallite size of samples prepared by U method (20 to 40 nm) was almost in the same range of the TiN crystallite size, but the crystallite size of the samples prepared by the other sol-gel methods (40 to 60 nm) was in the same range of the TiO2 crystallite size. Scanning electron microscopy (SEM) and B.E.T. surface area analyzer were used to evaluate the particle

  20. Recovery Act: Oxy-Combustion Technology Development for Industrial-Scale Boiler Applications. Task 4 - Testing in Alstom's 15 MWth Boiler Simulation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

    Alstom Power Inc. (Alstom), under U.S. DOE/NETL Cooperative Agreement No. DE-NT0005290, is conducting a development program to generate detailed technical information needed for application of oxy-combustion technology. The program is designed to provide the necessary information and understanding for the next step of large-scale commercial demonstration of oxy combustion in tangentially fired boilers and to accelerate the commercialization of this technology. The main project objectives include: Design and develop an innovative oxyfuel system for existing tangentially-fired boiler units that minimizes overall capital investment and operating costs; Evaluate performance of oxyfuel tangentially fired boiler systems in pilot scale tests at Alstom’s 15 MWth tangentially fired Boiler Simulation Facility (BSF); Address technical gaps for the design of oxyfuel commercial utility boilers by focused testing and improvement of engineering and simulation tools; Develop the design, performance and costs for a demonstration scale oxyfuel boiler and auxiliary systems; Develop the design and costs for both industrial and utility commercial scale reference oxyfuel boilers and auxiliary systems that are optimized for overall plant performance and cost; and, Define key design considerations and develop general guidelines for application of results to utility and different industrial applications. The project was initiated in October 2008 and the scope extended in 2010 under an ARRA award. The project is scheduled for completion by April 30, 2014. Central to the project is 15 MWth testing in the BSF, which provided in-depth understanding of oxy-combustion under boiler conditions, detailed data for improvement of design tools, and key information for application to commercial scale oxy-fired boiler design. Eight comprehensive 15 MWth oxy-fired test campaigns were performed with different coals, providing detailed data on combustion, emissions, and thermal behavior over a matrix of

  1. Effects of total pressure on non-grey gas radiation transfer in oxy-fuel combustion using the LBL, SNB, SNBCK, WSGG, and FSCK methods

    Science.gov (United States)

    Chu, Huaqiang; Gu, Mingyan; Consalvi, Jean-Louis; Liu, Fengshan; Zhou, Huaichun

    2016-03-01

    The effects of total pressure on gas radiation heat transfer are investigated in 1D parallel plate geometry containing isothermal and homogeneous media and an inhomogeneous and non-isothermal CO2-H2O mixture under conditions relevant to oxy-fuel combustion using the line-by-line (LBL), statistical narrow-band (SNB), statistical narrow-band correlated-k (SNBCK), weighted-sum-of-grey-gases (WSGG), and full-spectrum correlated-k (FSCK) models. The LBL calculations were conducted using the HITEMP2010 and CDSD-1000 databases and the LBL results serve as the benchmark solution to evaluate the accuracy of the other models. Calculations of the SNB, SNBCK, and FSCK were conducted using both the 1997 EM2C SNB parameters and their recently updated 2012 parameters to investigate how the SNB model parameters affect the results under oxy-fuel combustion conditions at high pressures. The WSGG model considered is the recently developed one by Bordbar et al. [19] for oxy-fuel combustion based on LBL calculations using HITEMP2010. The total pressure considered ranges from 1 up to 30 atm. The total pressure significantly affects gas radiation transfer primarily through the increase in molecule number density and only slightly through spectral line broadening. Using the 1997 EM2C SNB model parameters the accuracy of SNB and SNBCK is very good and remains essentially independent of the total pressure. When using the 2012 EM2C SNB model parameters the SNB and SNBCK results are less accurate and their error increases with increasing the total pressure. The WSGG model has the lowest accuracy and the best computational efficiency among the models investigated. The errors of both WSGG and FSCK using the 2012 EM2C SNB model parameters increase when the total pressure is increased from 1 to 10 atm, but remain nearly independent of the total pressure beyond 10 atm. When using the 1997 EM2C SNB model parameters the accuracy of FSCK only slightly decreases with increasing the total pressure.

  2. Crystal structures of four co-crystals of (E)-1,2-di(pyridin-4-yl)ethene with 4-alk-oxy-benzoic acids: 4-meth-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), 4-eth-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), 4-n-propoxybenzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1) and 4-n-but-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1).

    Science.gov (United States)

    Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki

    2016-11-01

    The crystal structures of four hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-(E)-1,2-di(pyridin-4-yl)ethene (2/1), namely, 2C8H8O3·C12H10N2, (I), 2C9H10O3·C12H10N2, (II), 2C10H12O3·C12H10N2, (III) and 2C11H14O3·C12H10N2, (IV), have been determined at 93 K. In compounds (I) and (IV), the asymmetric units are each composed of one 4-alk-oxy-benzoic acid mol-ecule and one half-mol-ecule of (E)-1,2-di(pyridin-4-yl)ethene, which lies on an inversion centre. The asymmetric unit of (II) consists of two crystallographically independent 4-eth-oxy-benzoic acid mol-ecules and one 1,2-di(pyridin-4-yl)ethene mol-ecule. Compound (III) crystallizes in a non-centrosymmetric space group (Pc) and the asymmetric unit comprises four 4-n-propoxybenzoic acid mol-ecules and two (E)-1,2-di(pyridin-4-yl)ethane mol-ecules. In each crystal, the acid and base components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1 unit of the acid and the base. In (I), (II) and (III), inter-molecular C-H⋯O inter-actions are observed. The 2:1 units of (I) and (II) are linked via C-H⋯O hydrogen bonds, forming tape structures. In (III), the C-H⋯O hydrogen bonds, except for those formed in the units, link the two crystallographically independent 2:1 units. In (IV), no C-H⋯O inter-actions are observed, but π-π and C-H⋯π inter-actions link the units into a column structure.

  3. Spectral characterisation of Sm{sup 3+} ions doped Oxy-fluoroborate glasses for visible orange luminescent applications

    Energy Technology Data Exchange (ETDEWEB)

    Mahamuda, Sk.; Swapna, K.; Venkateswarlu, M. [Department of Physics, KL University, Green Fields, Vaddeswaram 522502, Guntur (Dt.), AP (India); Srinivasa Rao, A., E-mail: drsrallam@gmail.com [Department of Physics, KL University, Green Fields, Vaddeswaram 522502, Guntur (Dt.), AP (India); Department of Applied Physics, Delhi Technological University, Bawana Road, New Delhi 110042 (India); Shakya, Suman; Vijaya Prakash, G. [Nanophotonics Laboratory, Department of Physics, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi 110016 (India)

    2014-10-15

    Oxy-fluoroborate (OFB) glasses doped with different concentrations of Sm{sup 3+} ions have been prepared using conventional melt quenching technique and characterised for their lasing potentialities using spectroscopic techniques such as FTIR, optical absorption, emission and emission decay measurements. The FTIR spectrum has been recorded to determine the various functional groups present in the OFB base glass. From the absorption spectra, the bonding parameters (δ) were evaluated to find the bonding nature present between Sm{sup 3+} ions with its neighbouring ligands. The Judd–Ofelt intensity (J–O) parameters (Ω{sub λ}, where λ=2, 4, and 6), measured from the experimental oscillator strengths of the absorption spectral futures, are used to evaluate the radiative parameters for the fluorescent transitions {sup 4}G{sub 5/2}→{sup 6}H{sub 5/2}, {sup 4}G{sub 5/2}→{sup 6}H{sub 7/2}, {sup 4}G{sub 5/2}→{sup 6}H{sub 9/2} and {sup 4}G{sub 5/2}→{sup 6}H{sub 11/2} of Sm{sup 3+} ions in OFB glasses. The asymmetric ratio has been evaluated to understand the local disorder of Sm{sup 3+} ions in the glass network. The experimental lifetimes (τ{sub exp}) measured from the decay curves are coupled with radiative lifetimes (τ{sub rad}) to measure quantum efficiency (η) of the prepared glasses. The experimental lifetimes (τ{sub exp}) for {sup 4}G{sub 5/2} emission state decrease with increase in Sm{sup 3+} ion concentration due to energy transfer. In order to elucidate the nature of energy transfer mechanism, the non-exponential decay curves are well fitted to the Inokuti–Hirayama model for S=6, which indicates that the energy transfer mechanism is of dipole–dipole type. The branching ratio (β{sub R}), stimulated emission cross-section (σ{sub se}) and quantum efficiency (η) values measured for the most intense emission transition {sup 4}G{sub 5/2}→{sup 6}H{sub 7/2} (598 nm) optimise the concentration of Sm{sup 3+} ions as 1 mol% to produce bright visible

  4. Crystal structure of 1,3-bis­[(E)-4-meth­oxy­benzyl­idene­amino]­propan-2-ol

    Science.gov (United States)

    Rivera, Augusto; Miranda-Carvajal, Ingrid; Ríos-Motta, Jaime; Bolte, Michael

    2016-01-01

    The title Schiff base, C19H22N2O3, was synthesized via the condensation reaction of 1,3-di­amino­propan-2-ol with 4-meth­oxy­benzaldehyde using water as solvent. The mol­ecule exists in an E,E conformation with respect to the C=N imine bonds and the dihedral angle between the aromatic rings is 37.25 (15)°. In the crystal, O—H⋯N hydrogen bonds link the mol­ecules into infinite C(5) chains propagating along the a-axis direction. The packing of these chains is consolidated by C—H⋯O inter­actions and C—H⋯π short contacts, forming a three-dimensional network. PMID:27980818

  5. The influence of selected parameters on the efficiency and economic charactersistics of the oxy-type coal unit with a membrane-cryogenic oxygen separator

    Directory of Open Access Journals (Sweden)

    Kotowicz Janusz

    2016-03-01

    Full Text Available In this paper a 600 MW oxy-type coal unit with a pulverized bed boiler and a membrane-cryogenic oxygen separator and carbon capture installation was analyzed. A membrane-cryogenic oxygen separation installation consists of a membrane module and two cryogenic distillation columns. In this system oxygen is produced with the purity equal to 95%. Installation of carbon capture was based on the physical separation method and allows to reduce the CO2 emission by 90%. In this work the influence of the main parameter of the membrane process – the selectivity coefficient, on the efficiency of the coal unit was presented. The economic analysis with the use of the break-even point method was carried out. The economic calculations were realized in view of the break-even price of electricity depending on a coal unit availability.

  6. (R)-Methyl {[(2-carb-oxy-bicyclo-[2.2.2]octan-1-yl)-ammonio]-methyl}-phos-phon-ate dichloro-methane 0.25-solvate.

    Science.gov (United States)

    Todorov, Petar; Calmes, Monique; Shivachev, Boris L; Nikolova, Rosica P

    2011-08-01

    The carb-oxy-lic acid mol-ecule of the title compound, C(11)H(20)NO(5)P·0.25CH(2)Cl(2), exists as a zwitterion with the H atom of the phospho-nate group being transferred to the imine N atom. In the asymmetric unit, there are two crystallographically independent acid mol-ecules adopting the same absolute configuration and differing slightly in their geometrical parameters. In each mol-ecule, the imino and carboxyl groups are connected via an intra-molecular N-H⋯O hydrogen bond. Inter-molecular O-H⋯O and N-H⋯O hydrogen bonds induce the formation of layers parallel to the ab plane. The dichloro-methane solvent mol-ecule, with a site occupancy of 0.5, is located between the layers.

  7. Methyl 2-methyl-4-(oxiran-2-ylmeth-oxy)-2H-1,2-benzothia-zine-3-carboxyl-ate 1,1-dioxide.

    Science.gov (United States)

    Ahmad, Matloob; Siddiqui, Hamid Latif; Zia-Ur-Rehman, Muhammad; Elsegood, Mark R J; Weaver, George W

    2010-01-09

    In the title compound, C(14)H(15)NO(6)S, the thia-zine ring adopts a distorted half-chair conformation. The structure displays several cooperative weak inter-molecular C-H⋯O hydrogen-bonding inter-actions, giving rise to a two-dimensional sheet packing motif. The CH(2) group in the meth-oxy linker to the oxirane ring, and the CH group in that ring, exhibit twofold positional disorder. The three-membered oxirane ring is twisted approximately perpendicular with respect to thia-zine ring (dihedral angle = 60/86° for the major/minor disorder components). 1,2-Benzothia-zines of this kind have a wide range of biological activities and are mainly used as medicines in the treatment of inflammation and rheumatoid arthritis.

  8. Synthesis, spectroscopic investigations, and computational study of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)-3-methoxybenzaldehyde

    Science.gov (United States)

    Kanaani, Ayoub; Ajloo, Davood; Kiyani, Hamzeh; Vakili, Mohamad; Farahani, Mahnaz; Amiri, Majid

    2016-08-01

    4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)-3-methoxybenzaldehyde has been synthesized in an attempt to obtain a new photochromic compound. The optimized molecular structure, mole fractions of title compound in trans and ana forms have been investigated. UV-visible spectra of the compound were also recorded. Upon irradiation with 300 nm light, the camel solid turned orange, in which a visible absorption band was observed at 475 nm. The electronic properties, such as HOMO, LUMO and band gap energies were obtained by the time-dependent DFT (TD-DFT) approach. The predicted nonlinear optical properties of the title compound are much greater than those of urea. Transition structures were calculated by QST3 and IRC methods which yielded the potential energy surface and activation energy.

  9. Crystal structures of (2E)-1-(3-bromo-thio-phen-2-yl)-3-(2-meth-oxy-phen-yl)prop-2-en-1-one and (2E)-1-(3-bromo-thio-phen-2-yl)-3-(3,4-di-meth-oxy-phen-yl)prop-2-en-1-one.

    Science.gov (United States)

    Naik, Vasant S; Shettigar, Venkataraya; Berglin, Tyler S; Coburn, Jillian S; Jasinski, Jerry P; Yathirajan, Hemmige S

    2015-08-01

    In the mol-ecules of the title compounds, (2E)-1-(3-bromo-thio-phen-2-yl)-3-(2-meth-oxy-phen-yl)prop-2-en-1-one, C14H11BrO2S, (I), which crystallizes in the space group P-1 with four independent mol-ecules in the asymmetric unit (Z' = 8), and (2E)-1-(3-bromo-thio-phen-2-yl)-3-(3,4-di-meth-oxy-phen-yl)prop-2-en-1-one, C15H13BrO3S, (II), which crystallizes with Z' = 8 in the space group I2/a, the non-H atoms are nearly coplanar. The mol-ecules of (I) pack with inversion symmetry stacked diagonally along the a-axis direction. Weak C-H⋯Br intra-molecular inter-actions in each of the four mol-ecules in the asymmetric unit are observed. In (II), weak C-H⋯O, bifurcated three-center inter-molecular inter-actions forming dimers along with weak C-H⋯π and π-π stacking inter-actions are observed, linking the mol-ecules into sheets along [001]. A weak C-H⋯Br intra-molecular inter-action is also present. There are no classical hydrogen bonds present in either structure.

  10. Crystal structure of (E)-2-[(2-bromopyridin-3-yl)methyl-idene]-6-meth-oxy-3,4-di-hydro-naphthalen-1(2H)-one and 3-[(E)-(6-meth-oxy-1-oxo-1,2,3,4-tetra-hydro-naphthalen-2-ylidene)meth-yl]pyridin-2(1H)-one.

    Science.gov (United States)

    Zingales, Sarah K; Moore, Morgan E; Goetz, Andrew D; Padgett, Clifford W

    2016-07-01

    The title compounds C17H14BrNO2, (I), and C17H15NO3, (II), were obtained from the reaction of 6-meth-oxy-3,4-di-hydro-2H-naphthalen-1-one and 2-bromo-nicotinaldehyde in ethanol. Compound (I) was the expected product and compound (II) was the oxidation product from air exposure. In the crystal structure of compound (I), there are no short contacts or hydrogen bonds. The structure does display π-π inter-actions between adjacent benzene rings and adjacent pyridyl rings. Compound (II) contains two independent mol-ecules, A and B, in the asymmetric unit; both are non-planar, the dihedral angles between the meth-oxy-benzene and 1H-pyridin-2-one mean planes being 35.07 (9)° in A and 35.28 (9)°in B. In each mol-ecule, the 1H-pyridin-2-one unit participates in inter-molecular N-H⋯O hydrogen bonding to another mol-ecule of the same type (A to A or B to B). The structure also displays π-π inter-actions between the pyridyl and the benzene rings of non-equivalent mol-ecules (viz., A to B and B to A).

  11. Coordination nature of aluminum (oxy)hydroxides formed under the influence of low molecular weight organic acids and a soil humic acid studied by X-ray absorption spectroscopy

    Science.gov (United States)

    Xu, R. K.; Hu, Y. F.; Dynes, J. J.; Zhao, A. Z.; Blyth, R. I. R.; Kozak, L. M.; Huang, P. M.

    2010-11-01

    Organic ligands in the environment hinder the formation of crystalline Al precipitation products by perturbing the hydrolytic and polymeric reactions of Al resulting in the formation of short-range ordered (SRO) mineral colloids with varying degrees of crystallinity. However, the effect of these ligands on the mechanisms of their formation and nature of the transformation products of Al (oxy)hydroxides at the atomic and molecular levels is not well understood. In this study, the coordination structure of Al in Al (oxy)hydroxides formed under the influence of varying concentrations of low molecular weight (LMW) organic acids such as citric, malic, salicylic and acetic acids and a humic acid (HA) was investigated with X-ray absorption near edge structure (XANES) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis. The Al K- and L-edge XANES spectra showed that with increasing LMW organic acid concentration the coordination number of Al changed from 6-fold to a mixture of 4- and 6-fold, except for acetate as acetate was unable to perturb the formation of Al (oxy)hydroxides at the acetate/Al molar ratio (MR) = 0.1. The proportion of 4-fold to 6-fold coordinated Al in the Al precipitation products depended on the structure and functionality of the LMW organic acids. The incorporation of the LMW organic acid into the network structure of Al (oxy)hydroxides prevented the formation of sheets/inter-layer H-bonding that was required for the formation of crystalline Al (oxy)hydroxides. The HA used in this study only slightly perturbed the crystallization of the Al (oxy)hydroxides at the concentrations used. The Al K-edge data showed that Al coordination number had not been altered in the presence of HA. The findings obtained in the present study are of fundamental significance in understanding the physicochemical behavior of soils and sediments, and their relation to the accumulation and transport of nutrients and pollutants in the

  12. Near-infrared oxymeter prototype for noninvasive analysis of rat brain oxygenation

    Science.gov (United States)

    Crespi, Francesco; Donini, Maurizio; Bandera, Andrea; Heidbreder, Christian; Salvatori, Giorgia; Rovati, Luigi

    2004-09-01

    The feasibility of non-invasive analysis of brain activities was studied in the attempt to overcome the major limitation of actual in vivo methodologies i.e. invasiveness. Optic fibre probes were used as optical head of a novel, highly sensitive near infrared continuous wave spectroscopy (CW-NIR) instrument. This prototype was designed for non-invasive analysis of the two main forms of haemoglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb), chromophores present in biological tissues. It was tested in peripheral tissue (human gastrocnemius muscle) and then reset to perform measurement on rat brain. In animal studies, the optical head was firmly placed using stereotaxic apparatus upon the sagittal line of anaesthetised adult rat's head, without any surgery. Then pharmacological treatments with saline (300μl s.c.) amphetamine (2mg/kg) or nicotine (0.4mg/kg) were performed. Within 10-20 min amphetamine substantially increased HbO2 and reduced Hb control levels. Nicotine produced a rapid initial increase followed by a decrease of HbO2. In contrast to amphetamine, nicotine treatment also reduced Hb and blood volume. These results support the capacity of our CW-NIR prototype to measure non-invasively HbO2 and Hb levels in the rat brain, markers of the degree of tissue oxygenation, index of blood level then of the state of brain metabolism.

  13. 38CrMoAl钢循环等离子氮碳氧硫共渗工艺的研究%Cycle plasma oxy-sulpho-nitrocarburizing of 38CrMoAl steel

    Institute of Scientific and Technical Information of China (English)

    钟厉; 陆亚

    2011-01-01

    对38CrMoA l钢进行了常规等离子渗氮、循环等离子渗氮以及循环等离子氮碳氧硫共渗处理,研究这几种工艺对表面硬度、渗层组织、硬度梯度的影响。结果表明:循环等离子氮碳氧硫共渗有利于形成共渗元素进一步扩散的通道,加速共渗元素的渗入;综合表面硬度和渗层厚度,循环等离子氮碳氧硫共渗工艺明显优于常规等离子渗氮和循环等离子渗氮。%Experiments of conventional plasma nitriding,cycle plasma nitriding and cycle plasma oxy-sulpho-nitrocarburizing were carried out on 38CrMoAl steel,and the effects of these processes on surface hardness,microstructure and gradient of hardness were investigated.Results show that the cycle plasma oxy-sulpho-nitrocarburizing is in favor of forming the diffuse channel for penetrating elements,and accelerating the permeability.From the results of surface hardness and thickness of layers,the cycle plasma oxy-sulpho-nitrocarburizing is obvious better than conventional plasma nitriding and cycle plasma nitriding.

  14. Crystal structure of bis-[μ-(4-meth-oxy-phen-yl)methane-thiol-ato-κ(2) S:S]bis-[chlorido-(η(6)-1-isopropyl-4-methyl-benzene)-ruthenium(II)] chloro-form disolvate.

    Science.gov (United States)

    Stíbal, David; Süss-Fink, Georg; Therrien, Bruno

    2015-10-01

    The mol-ecular structure of the title complex, [Ru2(C8H9OS)2Cl2(C10H14)2]·2CHCl3 or (p-MeC6H4Pr (i) )2Ru2(SCH2-p-C6H5-OCH3)2Cl2·2CHCl3, shows inversion symmetry. The two symmetry-related Ru(II) atoms are bridged by two 4-meth-oxy-α-toluene-thiol-ato [(4-meth-oxy-phen-yl)methane-thiol-ato] units. One chlorido ligand and the p-cymene ligand complete the typical piano-stool coordination environment of the Ru(II) atom. In the crystal, the CH moiety of the chloro-form mol-ecule inter-acts with the chlorido ligand of the dinuclear complex, while one Cl atom of the solvent inter-acts more weakly with the methyl group of the bridging 4-meth-oxy-α-toluene-thiol-ato unit. This assembly leads to the formation of supra-molecular chains extending parallel to [021].

  15. Formation of Mgx Nby Ox+y through the Mechanochemical Reaction of MgH2 and Nb2O5, and Its Effect on the Hydrogen-Storage Behavior of MgH2.

    Science.gov (United States)

    Pukazhselvan, D; Perez, José; Nasani, Narendar; Bdikin, Igor; Kovalevsky, Andrei V; Fagg, Duncan Paul

    2016-01-04

    The present study aims to understand the catalysis of the MgH2 -Nb2 O5 hydrogen storage system. To clarify the chemical interaction between MgH2 and Nb2 O5 , the mechanochemical reaction products of a composite mixture of MgH2 +0.167 Nb2 O5 was monitored at different time intervals (2, 5, 15, 30, and 45 min, as well as 1, 2, 5, 10, 15, 20, 25, and 30 h). The study confirms the formation of catalytically active Nb-doped MgO nanoparticles (typically Mgx Nby Ox+y , with a crystallite size of 4-8 nm) by transforming reactants through an intermediate phase typified by Mgm-x Nb2n-y O5n-(x+y) . The initially formed Mgx Nby Ox+y product is shown to be Nb rich, with the concentration of Mg increasing upon increasing milling time. The nanoscale end-product Mgx Nby Ox+y closely resembles the crystallographic features of MgO, but with at least a 1-4 % higher unit cell volume. Unlike MgO, which is known to passivate the surfaces in MgH2 system, the Nb-dissolved MgO effectively mediates the Mg-H2 sorption reaction in the system. We believe that this observation will lead to new developments in the area of catalysis for metal-gas interactions.

  16. Cholesteric Liquid-Crystal Copolyester, Poly[oxycarbonyl- 1,4-phenylene- oxy - 1,4 terephthaloyl- oxy- 1,4-phenylenecarbonyloxy (1,2-dodecane] [C34H36O8]n, Synthesized from Racemic Materials: Kinetics, Structure and Optical Characterization.

    Directory of Open Access Journals (Sweden)

    Mercedes Pérez Méndez

    2015-07-01

    Full Text Available The cholesteric liquid-crystal poly[oxycarbonyl-1,4-phenylene-oxy-1,4 terephthaloyl-oxy-1,4-phenylenecarbonyloxy(1,2-dodecane] [C34H36O8]n, named PTOBDME, synthesized by polycondensation reaction from equimolar quantities of TOBC and the racemic mixture of glycol (R-S-1,2 dodecanediol, exhibits unexpected optical activity and chiral morphology. The structure of racemic-PTOBDME, under different polymerization kinetics conditions, is analyzed by conventional NMR techniques and compared with those of polymer enantiomers R-PTOBDME and S-PTOBDME obtained starting R(+1,2 and S(-1,2-dodecanediol respectively. Molecular models based on the NMR signals intensities are proposed. The optical activity of racemicPTOBDME is evaluated by measuring the ORD values during kinetics study, and compared to the chiral polymers. Each enantiomeric polymer seems to present the same stereoregular head-tail, isotactic structure than the racemic, which we explain by the higher reactivity of the primary hydroxyl than the secondary one in the glycol through polycondensation. For each enantiomer, two independent sets of signals were observed by NMR, explained as two diastereomeric helical conformers: gg and gt, related with two possible staggered conformations, along the copolymer backbone. Chirality in racemic-PTOBDME is proposed to be due to the kinetic resolution of a preferable helical diastereomer, such as Sgt, with respect to the possible four forms, while the R/S ratio of asymmetric carbon atoms remained 50:50. Chiral amplification is observed in R-PTOBDME and S-PTOBDME due to a helical screw sense excess. Optimum yield was obtained for racemic PTOBDME, after 120 minutes polycondensated and decanted in toluene for 24 hours. Two weeks later a second fraction precipitated from the toluene mother liquor with 67.6% chiral excess. After eight months and two weeks a third fraction precipitated with 85.2% chiral excess.

  17. Four new koumine metabolites in rat liver microsomes.

    Science.gov (United States)

    Zhang, Lin; Du, Lan; Lv, Wen-Wen; Zhao, Qing-Chun; Hua, Wei; An, Ye; Guo, Tao; Wu, Li-Jun

    2013-01-01

    Four new metabolites M-1 [1,2,18,19-tetradehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-2 [1,2,4,21,18,19-hexadehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-3 [1,2,18,19-tetradehydro-4-demethyl-4-formaldehyde-3,17-epoxy-7,20(2H,19H)-cyclovobasan], and M-4 [1,2,4,21,18,19-hexadehydro-4-demethyl-4-oxy-3,17-epoxy-7,20(2H,19H)-cyclovobasan] were isolated from the chloroform extract of koumine incubated with phenobarbital-treated rat liver microsomes. The structures of M-1, M-2, M-3, and M-4 were elucidated by spectroscopic methods including ESI-TOF-MS, 1D, and 2D NMR experiments. The metabolic pathway of koumine was proposed. The cytotoxic activities between koumine and its metabolites were also compared in the A549 cell line.

  18. Comparative study on stability and coke deposition over supported Rh and FePO4 catalysts for oxy-bromination of methane

    Institute of Scientific and Technical Information of China (English)

    Ronghe; Lin; Yunjie; Ding; Runqin; Wang

    2014-01-01

    Rhodium- and iron phosphate-based catalysts are by far the most promising catalysts for oxy-bromination of methane(OBM) reaction. However, most literature reported either Rh- or FePO4-based catalysts, and the results were rarely studied in a uniform environmental condition. In this report, comparative study was conducted on silica- and silicon carbide-supported rhodium and iron phosphate catalysts with the main focuses on stability performance and coke deposition. The catalytic results demonstrated that the stability of both Rh- and FePO4-based catalysts was greatly influenced by the supports used, and silicon carbide-supported catalysts showed much better anti-coking ability as compared with silica-supported ones. Temperature-programmed oxidation over the used catalysts further indicated that the coke formation mechanisms were completely different between silica-supported rhodium and iron phosphate catalysts. While cokes might be caused by condensation of CH2Br2over supported iron phosphate, methane decomposition might be the reason for coke formation over silica-supported rhodium catalyst. These findings might pave the way for designing highly efficient and stable catalysts of the OBM reaction.

  19. Application of Argonne's Glass Furnace Model to longhorn glass corporation oxy-fuel furnace for the production of amber glass.

    Energy Technology Data Exchange (ETDEWEB)

    Golchert, B.; Shell, J.; Jones, S.; Energy Systems; Shell Glass Consulting; Anheuser-Busch Packaging Group

    2006-09-06

    The objective of this project is to apply the Argonne National Laboratory's Glass Furnace Model (GFM) to the Longhorn oxy-fuel furnace to improve energy efficiency and to investigate the transport of gases released from the batch/melt into the exhaust. The model will make preliminary estimates of the local concentrations of water, carbon dioxide, elemental oxygen, and other subspecies in the entire combustion space as well as the concentration of these species in the furnace exhaust gas. This information, along with the computed temperature distribution in the combustion space may give indications on possible locations of crown corrosion. An investigation into the optimization of the furnace will be performed by varying several key parameters such as the burner firing pattern, exhaust number/size, and the boost usage (amount and distribution). Results from these parametric studies will be analyzed to determine more efficient methods of operating the furnace that reduce crown corrosion. Finally, computed results from the GFM will be qualitatively correlated to measured values, thus augmenting the validation of the GFM.

  20. The effect of post-treatment of a high-velocity oxy-fuel Ni-Cr-Mo-Si-B coating part 2: Erosion-corrosion behavior

    Science.gov (United States)

    Shrestha, S.; Hodgkiess, T.; Neville, A.

    2001-12-01

    In this paper, a study of the erosion-corrosion characteristics of a Ni-Cr-Mo-Si-B coating applied by the high-velocity oxy-fuel (HVOF) process on to an austenitic stainless steel (UNS S31603) substrate are reported. The coatings were studied in the as-sprayed condition, after vacuum sealing with polymer impregnation and after vacuum furnace fusion. The erosion-corrosion characteristics were assessed in an impinging liquid jet of 3.5% NaCl solution at 18 °C at a velocity of 17 m/s at normal incidence in two conditions: (1) free from added solids and (2) containing 800 ppm silica sand. The methodology employed electrochemical control and monitoring to facilitate the identification of the separate and interrelated erosion and corrosion contributions to the erosion-corrosion process. The rates of erosion-corrosion damage were drastically accelerated in the presence of the suspended solids. The application of cathodic protection significantly reduced the deterioration process. The study showed the effect of sealing with polymer impregnation did not significantly alter the erosion-corrosion behavior of the sprayed coating. However, there was a significant improvement in erosion-corrosion durability afforded by the postfusion process. The mechanisms by which the improved performance of vacuum-fused coatings is achieved are discussed.

  1. V Xanes in Spinels as an Oxy-Barometer in Meteorites with Implications for Redox Variations in the Inner Solar System

    Science.gov (United States)

    Righter, K.; Sutton, S.; Danielson, L.; Pando, K.; Le, L.; Newville, M.

    2015-01-01

    The variation of oxygen fugacity within inner solar system materials spans a range of nearly 15 orders of magnitude. Igneous and metamorphic rocks commonly contain a mineral assemblage that allows oxygen fugacity to be calculated or con-strained such as FeTi oxides, olivine-opx-spinel, or some other oxy-barometer. Some rocks, however, contain a limited mineral assemblage and do not provide constraints on fO2 using mineral equilibria. Good examples of the latter are orthopyroxenites or dunites, such as diogenites, ALH 84001, chassignites, or brachinites. In fact it is no surprise that the fO2 of many of these achondrites is not well known, other than being "reduced" and below the metal saturation value. In order to bridge this gap in our understanding, we have initiated a study of V in chromites in achondrite. Because the V pre-edge peak intensity and energy in chromites varies with fO2, and this has been calibrated over a large fO2 range, we can apply this relation to rocks for which we otherwise have no fO2 constraints.

  2. How can a methadone and an opiate-positive immunoassay result be reconciled in a patient prescribed only OxyContin and Wellbutrin?

    Science.gov (United States)

    Abadie, Jude M

    2013-01-01

    Appropriate management of patients in pain clinics can be complex and sometimes confusing because providers must correctly interpret multiple sources of patient information. The correct interpretation of laboratory results is essential to guide subsequent patient treatment and management; however, laboratory and clinical pictures can appear to be conflicting in cases of substance abuse. Incorrect interpretation of laboratory results can multiply negative impacts on clinical outcomes and may lead to patient harm or death. This report introduces the complex nature involved in understanding and interpreting urine drug testing (UDT) results in pain patients who are prescribed opioid medications. Laboratory testing examples of UDT results are provided to illustrate the sometimes discordant nature of UDT interpretation. This case study describes one method of approaching cases where laboratory result interpretation in pain clinic patients is essential for medical treatment and management. The case presented in this manuscript illustrates a reconciliation of an opiate positive immunoassay result in a patient who was prescribed only OxyContin and Wellbutrin after traumatic amputations.

  3. Comparison of in vitro behavior of as-sprayed, alkaline-treated and collagen-treated bioceramic coatings obtained by high velocity oxy-fuel spray

    Energy Technology Data Exchange (ETDEWEB)

    Melero, H., E-mail: hortensia.melero.correas@gmail.com [Thermal Spray Centre, Universitat de Barcelona, Martí i Franqués, 1, 08028 Barcelona (Spain); Garcia-Giralt, N. [URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), RETICEF, Doctor Aiguader, 80, 08003 Barcelona (Spain); Fernández, J. [Thermal Spray Centre, Universitat de Barcelona, Martí i Franqués, 1, 08028 Barcelona (Spain); Díez-Pérez, A. [URFOA, IMIM (Institut Hospital del Mar d’Investigacions Mèdiques), RETICEF, Doctor Aiguader, 80, 08003 Barcelona (Spain); Servei de Medicina Interna, Hospital del Mar, Barcelona (Spain); Guilemany, J.M. [Thermal Spray Centre, Universitat de Barcelona, Martí i Franqués, 1, 08028 Barcelona (Spain)

    2014-07-01

    Hydroxyapatite (HAp)–TiO{sub 2} samples obtained using high velocity oxy-fuel spray (HVOF), that had previously shown excellent mechanical behaviour, were innovatively surface treated in order to improve their biological performance. The chosen treatments were an alkaline treatment to increase –OH radicals density on the surface (especially on TiO{sub 2} zones), and a collagen treatment to bond collagen fibrils to the –OH radicals present in hydroxyapatite. These coatings were analysed using scanning electron microscopy, energy-dispersive X-ray spectroscopy and infrared spectroscopy, and tested for human osteoblast biocompatibility and functionality. In the case of the alkaline treatment, although the –OH radicals density did not increase compared to the as-sprayed coatings, a nanostructured layer of sodium hydroxycarbonate precipitated on the surface, thus improving biological behaviour due to the nanoroughness effect. For the collagen-treated samples, collagen fibrils appeared well-adhered to the surface, and in vitro cell culture tests showed that these surfaces were much more conducive to cell adhesion and differentiation than the as-sprayed and alkaline-treated samples. These results pointed to collagen treatment as a very promising method to improve bioactivity of HAp–TiO{sub 2} thermal-sprayed coatings.

  4. Microstructural Characterization and Wear Behavior of Nano-Boride Dispersed Coating on AISI 304 Stainless Steel by Hybrid High Velocity Oxy-Fuel Spraying Laser Surface Melting

    Science.gov (United States)

    Sharma, Prashant; Majumdar, Jyotsna Dutta

    2015-07-01

    The current study concerns the detailed microstructural characterization and investigation of wear behavior of nano-boride dispersed coating developed on AISI 304 stainless steel by high velocity oxy-fuel spray deposition of nickel-based alloy and subsequent laser melting. There is a significant refinement and homogenization of microstructure with improvement in microhardness due to laser surface melting (1200 VHN as compared to 945 VHN of as-sprayed and 250 VHN of as-received substrate). The high temperature phase stability of the as-coated and laser melted surface has been studied by differential scanning calorimeter followed by detailed phase analysis at room and elevated temperature. There is a significant improvement in wear resistance of laser melted surface as compared to as-sprayed and the as-received one due to increased hardness and reduced coefficient of friction. The mechanism of wear has been investigated in details. Corrosion resistance of the coating in a 3.56 wt pct NaCl solution is significantly improved (4.43 E-2 mm/year as compared to 5 E-1 mm/year of as-sprayed and 1.66 mm/year of as-received substrate) due to laser surface melting as compared to as-sprayed surface.

  5. Predicting Radiative Heat Transfer in Oxy-Methane Flame Simulations: An Examination of Its Sensitivities to Chemistry and Radiative Property Models

    Directory of Open Access Journals (Sweden)

    Hassan Abdul-Sater

    2015-01-01

    Full Text Available Measurements from confined, laminar oxy-methane flames at different O2/CO2 dilution ratios in the oxidizer are first reported with measurements from methane-air flames included for comparison. Simulations of these flames employing appropriate chemistry and radiative property modeling options were performed to garner insights into the experimental trends and assess prediction sensitivities to the choice of modeling options. The chemistry was modeled employing a mixture-fraction based approach, Eddy dissipation concept (EDC, and refined global finite rate (FR models. Radiative properties were estimated employing four weighted-sum-of-gray-gases (WSGG models formulated from different spectroscopic/model databases. The mixture fraction and EDC models correctly predicted the trends in flame length and OH concentration variations, and the O2, CO2, and temperature measurements outside the flames. The refined FR chemistry model predictions of CO2 and O2 deviated from their measured values in the flame with 50% O2 in the oxidizer. Flame radiant power estimates varied by less than 10% between the mixture fraction and EDC models but more than 60% between the different WSGG models. The largest variations were attributed to the postcombustion gases in the temperature range 500 K–800 K in the upper sections of the furnace which also contributed significantly to the overall radiative transfer.

  6. High-Temperature Behavior of a High-Velocity Oxy-Fuel Sprayed Cr3C2-NiCr Coating

    Science.gov (United States)

    Kaur, Manpreet; Singh, Harpreet; Prakash, Satya

    2012-08-01

    High-velocity oxy-fuel (HVOF) sprayed coatings have the potential to enhance the high-temperature oxidation, corrosion, and erosion-corrosion resistance of boiler steels. In the current work, 75 pct chromium carbide-25 pct (nickel-20 pct chromium) [Cr3C2-NiCr] coating was deposited on ASTM SA213-T22 boiler steel using the HVOF thermal spray process. High-temperature oxidation, hot corrosion, and erosion-corrosion behavior of the coated and bare steel was evaluated in the air, molten salt [Na2SO4-82 pct Fe2(SO4)3], and actual boiler environments under cyclic conditions. Weight-change measurements were taken at the end of each cycle. Efforts were made to formulate the kinetics of the oxidation, corrosion, and erosion-corrosion. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM)/energy dispersive spectroscopy (EDS) techniques were used to analyze the oxidation products. The coating was found to be intact and spallation free in all the environments of the study in general, whereas the bare steel suffered extensive spallation and a relatively higher rate of degradation. The coating was found to be useful to enhance the high-temperature resistance of the steel in all the three environments in this study.

  7. Kilogram-scale synthesis of iron oxy-hydroxides with improved arsenic removal capacity: study of Fe(II) oxidation--precipitation parameters.

    Science.gov (United States)

    Tresintsi, Sofia; Simeonidis, Konstantinos; Vourlias, George; Stavropoulos, George; Mitrakas, Manassis

    2012-10-15

    Various iron oxy-hydroxides were synthesized in a continuous flow kilogram-scale production reactor through the precipitation of FeSO(4) and FeCl(2) in the pH range 3-12 under intense oxidative conditions to serve as arsenic adsorbents. The selection of the optimum adsorbent and the corresponding conditions of the synthesis was based not only on its maximum As(III) and As(V) adsorption capacity but also on its potential efficiency to achieve the arsenic health regulation limit in NSF challenge water. As a result, the adsorbent prepared at pH 4, which consists of schwertmannite, was selected because it exhibited the highest adsorption capacity of 13 μg As(V)/mg, while maintaining a residual arsenic concentration of 10 μg/L at an equilibrium pH 7. The high surface charge and the activation of an ion-exchange mechanism between SO(4)(2-) adsorbed in the Stern layer and arsenate ions were found to significantly contribute to the increased adsorption capacity. Adsorption capacity values observed in rapid scale column experiments illustrate the improved efficiency of the qualified adsorbent compared to the common commercial arsenic adsorbents.

  8. Effects of low concentration biodiesel blends application on modern passenger cars. Part 3: impact on PAH, nitro-PAH, and oxy-PAH emissions.

    Science.gov (United States)

    Karavalakis, Georgios; Fontaras, Georgios; Ampatzoglou, Dimitrios; Kousoulidou, Marina; Stournas, Stamoulis; Samaras, Zissis; Bakeas, Evangelos

    2010-05-01

    This study explores the impact of five different types of methyl esters on polycyclic aromatic hydrocarbon (PAH), nitrated-PAH and oxygenated PAH emissions. The measurements were conducted on a chassis dynamometer, according to the European regulation. Each of the five different biodiesels was blended with EN590 diesel at a proportion of 10-90% v/v (10% biodiesel concentration). The vehicle was a Euro 3 compliant common-rail diesel passenger car. Emission measurements were performed over the NEDC and compared with those of the real traffic-based Artemis driving cycles. The experimental results showed that the addition of biodiesel led to some important increases in low molecular-weight PAHs (phenanthrene and anthracene) and to both increases and reductions in large PAHs which are characterised by their carcinogenic and mutagenic properties. Nitro-PAHs were found to reduce with biodiesel whereas oxy-PAH emissions presented important increases with the biodiesel blends. The impact of biodiesel source material was particularly clear on the formation of PAH compounds. It was found that most PAH emissions decreased as the average load and speed of the driving cycle increased. Cold-start conditions negatively influenced the formation of most PAH compounds. A similar trend was observed with particulate alkane emissions.

  9. Zwitterionic 4-bromo-6-meth-oxy-2-{[tris-(hy-droxy-meth-yl)methyl]-iminiumyl-meth-yl}phenolate: crystal structure and Hirshfeld surface analysis.

    Science.gov (United States)

    Lee, See Mun; Lo, Kong Mun; Tan, Sang Loon; Tiekink, Edward R T

    2016-08-01

    In the solid state, the title compound, C12H16BrNO5 [systematic name: 4-bromo-2-((1E)-{[1,3-dihy-droxy-2-(hy-droxy-meth-yl)propan-2-yl]iminium-yl}meth-yl)-6-meth-oxy-benzen-1-olate], C12H16BrNO5, is found in the keto-amine tautomeric form, with an intra-molecular iminium-N-H⋯O(phenolate) hydrogen bond and an E conformation about the C=N bond. Both gauche (two) and anti relationships are found for the methyl-hydroxy groups. In the crystal, a supra-molecular layer in the bc plane is formed via hy-droxy-O-H⋯O(hy-droxy) and charge-assisted hy-droxy-O-H⋯O(phenolate) hydrogen-bonding inter-actions; various C-H⋯O inter-actions provide additional cohesion to the layers, which stack along the a axis with no directional inter-actions between them. A Hirshfeld surface analysis confirms the lack of specific inter-actions in the inter-layer region.

  10. Bis[O-propan-2-yl (4-eth-oxy-phen-yl)dithio-phospho-nato-κ(2) S,S']nickel(II).

    Science.gov (United States)

    Sewpersad, Shirveen; Van Zyl, Werner E

    2012-12-01

    The title compound, [Ni(C11H16O2PS2)2], is a neutral four-coordinate mononuclear complex with a square-planar geometry. The complex lies on an inversion center. The metal atom is surrounded by two chelating isobidentate O-propan-2-yl (4-eth-oxy-phen-yl)dithio-phospho-nate ligands in a trans configuration binding through the S-donor atoms. The Ni-S bond lengths are 2.2328 (5) and 2.2369 (5) Å, an insignificant difference to be considered anisobidentate. The Ni⋯P separation is 2.8224 (5) Å and the S-P bond lengths are 2.0035 (7) and 2.0053 (7) Å. The S-Ni-S (chelating) and S-Ni-S (trans) bond angles are 88.321 (18) and 180°. The Ni-S-P bond angles are 83.26 (2) and 83.33 (2)°, indicating a very minor distortion from ideal square-planar geometry for the Ni atom. The P atom, however, is distorted quite significantly from an ideal tetra-hedral geometry, as reflected by the S-P-S and O-P-C bond angles of 101.93 (3) and 100.70 (7)°, respectively.

  11. Synthesis, spectroscopic investigations and computational study of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)benzaldehyde

    Science.gov (United States)

    Kanaani, A.; Ajloo, D.; Kiyani, H.; Farahani, M.

    2014-04-01

    The molecular structure, vibrational frequencies, corresponding vibrational assignments of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)benzaldehyde in “trans” and “ana” forms have been investigated by UV-Vis, FT-IR and NMR spectroscopy as well as density functional theory (DFT) B3LYP method with 6-311++G(d,p) basis set. The vibrational analysis of the two forms of cited compound was performed by means of infrared absorption spectroscopy in combination with theoretical simulations. The obtained geometrical parameters and wavenumbers of vibrational normal modes from the DFT method were in good consistency with the experimental values. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Computed molecular orbital and time dependent DFT oscillator renderings agree closely with experimental observations. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. In order to predict the reactive sites, a molecular electrostatic potential map (MEP) for the title compound was obtained. Transition structures were calculated by QST3 and IRC methods which yielded the potential energy surface and activation energy.

  12. Arecoline inhibits catecholamine release from perfused rat adrenal gland

    Institute of Scientific and Technical Information of China (English)

    Dong-yoon LIM; Il-sik KIM

    2006-01-01

    Aim: To study the effect of arecoline, an alkaloid isolated from Areca catechu, on the secretion of catecholamines (CA) evoked by cholinergic agonists and the membrane depolarizer from isolated perfused rat adrenal gland. Methods: Adrenal glands were isolated from male Sprague-Dawley rats. The adrenal glands were perfused with Krebs bicarbonate solution by means of a peristaltic pump. The CA content of the perfusate was measured directly using the fluorometric method.Results: Arecoline (0.1-1.0 mmol/L) perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by acetylcholine (ACh) (5.32 mmol/L), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP) (100 μmol/L for 2 min) and 3-(m-choloro-phenyl-carbamoyl-oxy)-2-butynyl trimethyl ammonium chloride (McN-A-343) (100 μmol/L for 2 min). However, lower doses of arecoline did not affect CA secretion of high K+ (56 mmol/L); higher doses greatly reduced CA secretion of high K+. Arecoline also failed to affect basal catecholamine output. Furthermore, in adrenal glands loaded with arecoline (0.3 mmol/L), CA secretory response evoked by Bay-K-8644 (10 μmol/L), an activator of L-type Ca2+ channels, was markedly inhibited, whereas CA secretion by cyclopiazonic acid (10 μmol/L), an inhibitor of cytoplasmic Ca2+-ATPase, was not affected. Nicotine (30 μmol/L), which was peffused into the adrenal gland for 60min, however, initially enhanced ACh-evoked CA secretory responses. As time elapsed, these responses became more inhibited, whereas the initially enhanced high K+-evoked CA release diminished. CA secretion evoked by DMPP and McNA-343 was significantly depressed in the presence of nicotine. Conclusion:Arecoline dose-dependently inhibits CA secretion from isolated perfused rat adrenal gland evoked by activation of cholinergic receptors. At lower doses arecoline does not inhibit CA secretion through membrane depolarization, but at larger doses it does. This inhibitory

  13. Pilot-Scale Demonstration of a Novel, Low-Cost Oxygen Supply Process and its Integration with Oxy-Fuel Coal-Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Krish Krishnamurthy; Divy Acharya; Frank Fitch

    2008-09-30

    In order to achieve DOE targets for carbon dioxide capture, it is crucial not only to develop process options that will generate and provide oxygen to the power cycle in a cost-effective manner compared to the conventional oxygen supply methods based on cryogenic air separation technology, but also to identify effective integration options for these new technologies into the power cycle with carbon dioxide capture. The Linde/BOC developed Ceramic Autothermal Recovery (CAR) process remains an interesting candidate to address both of these issues by the transfer of oxygen from the air to a recycled CO{sub 2} rich flue-gas stream in a cyclic process utilizing the high temperature sorption properties of perovskites. Good progress was made on this technology in this project, but significant challenges remain to be addressed before CAR oxygen production technology is ready for commercial exploitation. Phase 1 of the project was completed by the end of September 2008. The two-bed 0.7 tons/day O2 CAR process development unit (PDU) was installed adjacent to WRI's pilot scale coal combustion test facility (CTF). Start-up and operating sequences for the PDU were developed and cyclic operation of the CAR process demonstrated. Controlled low concentration methane addition allowed the beds to be heated up to operational temperature (800-900 C) and then held there during cyclic operation of the 2-bed CAR process, in this way overcoming unavoidable heat losses from the beds during steady state operation. The performance of the PDU was optimized as much as possible, but equipment limitations prevented the system from fully achieving its target performance. Design of the flue gas recirculation system to integrate CAR PDU with the CTF and the system was completed and integrated tests successfully performed at the end of the period. A detailed techno-economic analysis was made of the CAR process for supplying the oxygen in oxy-fuel combustion retrofit option using AEP's 450

  14. An update of the oxidation-inflammation theory of aging: the involvement of the immune system in oxi-inflamm-aging.

    Science.gov (United States)

    De la Fuente, Mónica; Miquel, Jaime

    2009-01-01

    The aging process is one of the best examples of the effects of a deterioration of homeostasis, since aging is accompanied by an impairment of the physiological systems including the homeostatic systems such as the immune system. We propose an integrative theory of aging providing answers to the how (oxidation), where first (mitochondria of differentiated cells) and why (pleiotropic genes) this process occurs. In agreement with this oxidation-mitochondrial theory of aging, we have observed that the age-related changes of immune functions have as their basis an oxidative and inflammatory stress situation, which has among its intracellular mechanisms the activation of NFkappaB in immune cells. Moreover, we have also observed that several functions of immune cells are good markers of biological age and predictors of longevity. Based on the above we have proposed the theory of oxidation-inflammation as the main cause of aging. Accordingly, the chronic oxidative stress that appears with age affects all cells and especially those of the regulatory systems, such as the nervous, endocrine and immune systems and the communication between them. This fact prevents an adequate homeostasis and, therefore, the preservation of health. We have also proposed a key involvement of the immune system in the aging process of the organism, concretely in the rate of aging, since there is a relation between the redox state and functional capacity of the immune cells and the longevity of individuals. Moreover, the role of the immune system in senescence could be of universal application. A confirmation of the central role of the immune system in oxi-inflamm-aging is that the administration of adequate amounts of antioxidants in the diet, improves the immune functions, decreasing their oxidative stress, and consequently increases the longevity of the subjects.

  15. Structure and Reactivity of a Thermostable Prokaryotic Nitric-oxide Synthase That Forms a Long-lived Oxy-Heme Complex

    Energy Technology Data Exchange (ETDEWEB)

    Sudhamsu,J.; Crane, B.

    2006-01-01

    In an effort to generate more stable reaction intermediates involved in substrate oxidation by nitric-oxide synthases (NOSs), we have cloned, expressed, and characterized a thermostable NOS homolog from the thermophilic bacterium Geobacillus stearothermophilus (gsNOS). As expected, gsNOS forms nitric oxide (NO) from L-arginine via the stable intermediate N-hydroxy L-arginine (NOHA). The addition of oxygen to ferrous gsNOS results in long-lived heme-oxy complexes in the presence (Soret peak 427 nm) and absence (Soret peak 413 nm) of substrates L-arginine and NOHA. The substrate-induced red shift correlates with hydrogen bonding between substrate and heme-bound oxygen resulting in conversion to a ferric heme-superoxy species. In single turnover experiments with NOHA, NO forms only in the presence of H4B. The crystal structure of gsNOS at 3.2 A Angstroms of resolution reveals great similarity to other known bacterial NOS structures, with the exception of differences in the distal heme pocket, close to the oxygen binding site. In particular, a Lys-356 (Bacillus subtilis NOS) to Arg-365 (gsNOS) substitution alters the conformation of a conserved Asp carboxylate, resulting in movement of an Ile residue toward the heme. Thus, a more constrained heme pocket may slow ligand dissociation and increase the lifetime of heme-bound oxygen to seconds at 4 degC. Similarly, the ferric-heme NO complex is also stabilized in gsNOS. The slow kinetics of gsNOS offer promise for studying downstream intermediates involved in substrate oxidation.

  16. Impact of interstitial oxygen trapped in silicon during plasma growth of silicon oxy-nitride films for silicon solar cell passivation

    Science.gov (United States)

    Saseendran, Sandeep S.; Saravanan, S.; Raval, Mehul C.; Kottantharayil, Anil

    2016-03-01

    Low temperature oxidation of silicon in plasma ambient is a potential candidate for replacing thermally grown SiO2 films for surface passivation of crystalline silicon solar cells. In this work, we report the growth of silicon oxy-nitride (SiOxNy) film in N2O plasma ambient at 380 °C. However, this process results in trapping of interstitial oxygen within silicon. The impact of this trapped interstitial oxygen on the surface passivation quality is investigated. The interstitial oxygen trapped in silicon was seen to decrease for larger SiOxNy film thickness. Effective minority carrier lifetime (τeff) measurements on n-type float zone silicon wafers passivated by SiOxNy/silicon nitride (SiNv:H) stack showed a decrease in τeff from 347 μs to 68 μs, for larger SiOxNy film thickness due to degradation in interface properties. From high frequency capacitance-voltage measurements, it was concluded that the surface passivation quality was governed by the interface parameters (fixed charge density and interface state density). High temperature firing of the SiOxNy/SiNv:H stack resulted in a severe degradation in τeff due to migration of oxygen across the interface into silicon. However, on using the SiOxNy/SiNv:H stack for emitter surface passivation in screen printed p-type Si solar cells, an improvement in short wavelength response was observed in comparison to the passivation by SiNv:H alone, indicating an improvement in emitter surface passivation quality.

  17. Effect of solvent environment on the Photophysics of a newly synthesized bioactive 7-oxy(5-selenocyanato-pentyl)-2H-1-benzopyran-2-one

    Energy Technology Data Exchange (ETDEWEB)

    Dhar, Sayaree [Department of Chemistry, Jadavpur University, Kolkata 700032 (India); Rana, Dipak Kumar [Department of Chemistry, Saldiha College, The University of Burdwan, Bankura 722173 (India); Singha Roy, Somnath [Department of Cancer Chemoprevention, Chittaranjan National Cancer Institute, 37, S. P. Mukherjee Road, Kolkata 700026 (India); Roy, Swapnadip [Department of Chemistry, Jadavpur University, Kolkata 700032 (India); Bhattacharya, Sudin [Department of Cancer Chemoprevention, Chittaranjan National Cancer Institute, 37, S. P. Mukherjee Road, Kolkata 700026 (India); Bhattacharya, Subhash Chandra, E-mail: sbjuchem@yahoo.com [Department of Chemistry, Jadavpur University, Kolkata 700032 (India)

    2012-04-15

    The synthesis and solvatochromic behavior of the compound, 7-oxy(5-selenocyanato-pentyl)-2H-1-benzopyran-2-one (PCM), a pervasive, bioactive coumarin derivative, which is expected to possess antioxidative properties and other important therapeutic activities of significant potency with low systematic toxicity, have been reported employing steady state and time resolved fluorescence techniques. Spectroscopic studies reveal that the solvatochromic behavior of the probe depends not only on the polarity of the medium but also on the hydrogen bonding properties of the solvents. Specific hydrogen bonding interaction of PCM in polar solvents modulated the order of the two close-lying lowest singlet states. The photophysical response of PCM in different solvents has been explained considering solute-solvent interactions. To corroborate these results, we performed the ground-state geometry, lowest energy transition and the UV-vis spectrum of PCM using the density functional theory (DFT) and the time-dependent density functional theory (TD-DFT) at B3LYP/6-31G{sup Low-Asterisk} level. We found excellent correlation between the predicted and experimental spectral data, providing a useful tool in the design of new fluorogenic probes having potential therapeutic activity. - Highlights: Black-Right-Pointing-Pointer Synthesis and photophysical behavior of the bioactive PCM. Black-Right-Pointing-Pointer The order of the two close-lying lowest singlet states is modulated by H-bonding interaction in polar solvents. Black-Right-Pointing-Pointer In non-polar solvent non-radiative path favor due to mixing of n,{pi}{sup Low-Asterisk} and {pi},{pi}{sup Low-Asterisk} singlet states. Black-Right-Pointing-Pointer Quantum chemical calculation has been employed to corroborate with experimental finding.

  18. Crystal structures of bis­[(9S,13S,14S)-3-meth­oxy-17-methyl­morphinanium] tetra­chlorido­cobaltate and tetra­chlorido­cuprate

    Science.gov (United States)

    Gauchat, Eric; Nazarenko, Alexander Y.

    2017-01-01

    (9S,13S,14S)-3-Meth­oxy-17-methyl­morphinan (dextromethorphan) forms two isostructural salts with (a) tetra­chlorido­cobaltate, namely bis­[(9S,13S,14S)-3-meth­oxy-17-methyl­morphinanium] tetra­chlorido­cobaltate, (C18H26NO)2[CoCl4], and (b) tetra­chlorido­cuprate, namely bis­[(9S,13S,14S)-3-meth­oxy-17-methyl­morphinanium] tetra­chlorido­cuprate, (C18H26NO)2[CuCl4]. The distorted tetra­hedral anions are located on twofold rotational axes. The dextromethorphan cation can be described as being composed of two ring systems, a tetra­hydro­naphthalene system A+B and a deca­hydro­isoquinolinium subunit C+D, that are nearly perpendicular to one another: the angle between mean planes of the A+B and C+D moieties is 78.8 (1)° for (a) and 79.0 (1)° for (b). Two symmetry-related cations of protonated dextromethorphan are connected to the tetra­chlorido­cobaltate (or tetra­chlorido­cuprate) anions via strong N—H⋯Cl hydrogen bonds, forming neutral ion associates. These associates are packed in the (001) plane with no strong attractive bonding between them. Both compounds are attractive crystalline forms for unambiguous identification of the dextromethorphan and, presumably, of its optical isomer, levomethorphan. PMID:28083138

  19. A model of hemodynamic responses of rat tumors to hyperoxic gas challenge

    Science.gov (United States)

    Xia, Mengna; Mason, Ralph P.; Liu, Hanli

    2005-04-01

    We measured the changes of oxy-hemoglobin (Δ[HbO2]) and deoxy-hemoglobin concentration (Δ[Hb]) in rat breast 13762NF tumors with respect to oxygen or carbogen inhalation using near-infrared spectroscopy (NIRS). The changes in tumor blood flow can be estimated from the NIRS data provided with certain model assumptions. In the theoretical approach, we modified the Windkessel model so as to associate the mathematical model with such physiological parameters of tumor vasculature as total hemoglobin concentration ([HbT]), tumor blood flow (TBF), and tumor metabolic rate of oxygen (TMRO2). The computational results show that hyperoxic gas administration to the rat tumors always gave rise to improvement of tumor Δ[HbO2], while the same hyperoxic gas intervention could result in different responses in tumor [HbT], TBF, and TMRO2. This preliminary study has demonstrated that NIRS, a noninvasive tool to monitor tumor oxygenation, may also be used to estimate tumor perfusion and oxygen consumption rate in response to therapeutic interventions, if a suitable mathematical model is provided.

  20. Ignition and Combustion of Pulverized Coal and Biomass under Different Oxy-fuel O2/N2 and O2/CO2 Environments

    Science.gov (United States)

    Khatami Firoozabadi, Seyed Reza

    This work studied the ignition and combustion of burning pulverized coals and biomasses particles under either conventional combustion in air or oxy-fuel combustion conditions. Oxy-fuel combustion is a 'clean-coal' process that takes place in O2/CO2 environments, which are achieved by removing nitrogen from the intake gases and recirculating large amounts of flue gases to the boiler. Removal of nitrogen from the combustion gases generates a high CO2-content, sequestration-ready gas at the boiler effluent. Flue gas recirculation moderates the high temperatures caused by the elevated oxygen partial pressure in the boiler. In this study, combustion of the fuels took place in a laboratory laminar-flow drop-tube furnace (DTF), electrically-heated to 1400 K, in environments containing various mole fractions of oxygen in either nitrogen or carbon-dioxide background gases. The experiments were conducted at two different gas conditions inside the furnace: (a) quiescent gas condition (i.e., no flow or inactive flow) and, (b) an active gas flow condition in both the injector and furnace. Eight coals from different ranks (anthracite, semi-snthracite, three bituminous, subbituminous and two lignites) and four biomasses from different sources were utilized in this work to study the ignition and combustion characteristics of solid fuels in O2/N2 or O2/CO2 environments. The main objective is to study the effect of replacing background N2 with CO2, increasing O2 mole fraction and fuel type and rank on a number of qualitative and quantitative parameters such as ignition/combustion mode, ignition temperature, ignition delay time, combustion temperatures, burnout times and envelope flame soot volume fractions. Regarding ignition, in the quiescent gas condition, bituminous and sub-bituminous coal particles experienced homogeneous ignition in both O2/N 2 and O2/CO2 atmospheres, while in the active gas flow condition, heterogeneous ignition was evident in O2/CO 2. Anthracite, semi

  1. Rat Genome Database (RGD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Rat Genome Database (RGD) is a collaborative effort between leading research institutions involved in rat genetic and genomic research to collect, consolidate,...

  2. In vitro metabolism of the anti-androgenic fungicide vinclozolin by rat liver microsomes.

    Science.gov (United States)

    Sierra-Santoyo, Adolfo; Angeles-Soto, Esperanza; de Lourdes López-González, Ma; Harrison, Randy A; Hughes, Michael F

    2012-03-01

    Vinclozolin (V) is a fungicide used in agricultural settings. V administered to rats is hydrolyzed to 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, M1 and M2 have antiandrogenic properties by interacting with the androgen receptor. Data on V, M1 and M2 biotransformation are limited. Our objective was to characterize V metabolism by rat liver microsomes. V was incubated with non-treated adult male Long-Evans rat liver microsomes and NADPH. Several metabolites were detected following the extraction of incubate with acetonitrile and analysis by HPLC/DAD/MSD. One metabolite was identified as [3-(3,5-dichlorophenyl)-5-methyl-5-(1,2-dihydroxyethyl)-1,3-oxazolidine-2,4-dione] (M4), which was gradually converted to 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutylanilide (M5). Both co-eluted in the same HPLC peak. Another metabolite ([M7]) was detected by UV but was unstable for mass spectral analysis. The K(M app) for co-eluted M4/M5 and [M7] was 53.7 and 135.4 μM, the V(max app) was 0.812 and 0.669 nmoles/min/mg protein, and CL(int) was 15.1 and 4.9 ml/min/g protein, respectively. Pilocarpine, orphenadrine and proadifen and anti-rat cytochrome P450 (CYP)2A, 2B and 3A antibodies inhibited M4/M5 and [M7] formation. These results indicate that V is efficiently metabolized by CYP. Determination of the metabolites of V will provide further insight into the relationship between toxicity and tissue dose of V and its metabolites.

  3. Comparative Studies on the Combustion Kinetics of Chars Prepared from Brown and Bituminous Coals under Air (O_2/N_2) and Oxy-fuel (O_2/CO_2) Conditions

    OpenAIRE

    Kim, Hyun-Seok; Wada, Nozomi; Nozawa, Sohey; Matsushita, Yohsuke; Yamamoto, Tsuyoshi; Oomori, Motohira; Harada, Tatsuro; Miyawaki, Jin; Yoon, Seong-Ho; Mochida, Isao

    2012-01-01

    This paper deals with the application of a solid-gas reaction model which can describe the combustion and gasification mechanism for air (O_2/N_2) and oxy-fuel (O_2/CO_2) conditions. Loy Yang brown coal was used as a sample after pyrolysis, together with Newlands coal as bituminous coal for comparison of coal ranks. By carrying out the thermogravimetric analysis (TGA) run under non-isothermal conditions, chemical reaction rates of partial oxidation reaction and gasification reaction were esti...

  4. 2-[1-(4-Bromo­phen­yl)-3-hy­droxy-3-(4-meth­oxy­phen­yl)prop­yl]cyclo­hexa­nol

    Science.gov (United States)

    Çelik, Ísmail; Akkurt, Mehmet; Gezegen, Hayreddin; Üremiş, Muhammed M.; Duteanu, Narcis

    2013-01-01

    In the title compound, C22H27BrO3, the cyclo­hexane ring adopts a chair conformation. The dihedral angle between the benzene rings is 41.9 (4)°. In the crystal, mol­ecules are linked by O—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional network. In addition, π–π stacking inter­actions [centroid–centroid distance = 3.953 (6) Å] between the benzene rings of the meth­oxy­benzene groups occur. PMID:24046654

  5. PHASE STRUCTURE AND THERMAL BEHAVIOR OF LIQUID CRYSTALLINE MULTI-BLOCK COPOLYMERS,POLY[1,6-BIS(4-OXYBENZOYL-OXY)HEXANE TEREPHTHALATE]-b-BISPHENOL A POLYCARBONATE

    Institute of Scientific and Technical Information of China (English)

    Hui-qing Zhang; Xiong-yan Zhao; De-shan Liu; Qi-xiang Zhou

    1999-01-01

    Liquid crystalline multi-block copolymers poly[1,6-bis(4-oxybenzoyl-oxy)hexane terephthalate]-b-bisphenol A polycarbonate (PHTH-6-b-PC) with different segments of polycarbonate (PC) and thermotropic polyester PHTH-6 were synthesized in tetrachloroethane at 144~146℃. The influence of segment length on the resulting phase structure and thermal behavior of block copolymers was also discussed. It is demonstrated by TEM and DMA that the resulting block copolymers show a considerable microphase separation. The degree of phase separation and the thermal behavior of the block copolymers are strongly dependent on the molecular weight of the segments incorporated.

  6. [4-(4-Meth-oxy-phen-yl)-2-(pyridin-3-yl)-1,3-thia-zol-5-yl][4-(tri-fluoro-meth-yl)phen-yl]methanone.

    Science.gov (United States)

    Pampa, K J; Abdoh, M M M; Swaroop, T R; Rangappa, K S; Lokanath, N K

    2013-01-01

    In the title compound, C23H15F3N2O2S, the thia-zole ring makes dihedral angles of 12.98 (13), 49.30 (11) and 49.83 (12)° with the pyridine ring, the meth-oxy-phenyl ring and the (tri-fluoro-meth-yl)phenyl ring, respectively. In the crystal, mol-ecules are connected via C-H⋯O hydrogen bonds, forming chains along [010]. There are also C-H⋯π and C-F⋯π inter-actions present, forming a three-dimensional structure.

  7. The effect of propofol postconditioning on the expression of K(+)-Cl(-)-co-transporter 2 in GABAergic inhibitory interneurons of acute ischemia/reperfusion injury rats.

    Science.gov (United States)

    Wang, Hongbai; Liu, Shuying; Wang, Haiyun; Wang, Guolin; Zhu, Ai

    2015-02-09

    It has been shown in our previous study that propofol postconditioning enhanced the activity of phosphatidylinositol-3-kinase (PI3K) and prevented the internalization of GluR2 subunit of α-amino-3-hydroxyl-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, thus provided neuroprotection in cerebral ischemia/reperfusion (I/R) injury. Regarding inhibitory system in CNS, K(+)-Cl(-)-co-transporter 2 (KCC2), a Cl(-) extruder, plays a critical role in gamma-aminobutyric acid (GABA) inhibitory effect in mature central neurons. However, the effect of propofol postconditioning on the expression of KCC2 in GABAergic interneurons is unclear. Therefore, in this article we describe the role of KCC2 in GABAergic interneurons in the ipsilateral hippocampal CA1 region of adult rats and the effects of propofol postconditioning on this region. Herein we demonstrate that propofol postconditioning (20mg/kg/h, 2h) improved rats' neurobehavioral abilities, increased the number of survival neurons, and up-regulated neuronal KCC2 expression in glutamic acid decarboxylase 67 (GAD67) expressing GABAergic interneurons in hippocampal CA1 region at 24h after I/R. In contrast, when rats were injected with the KCC2 antagonist, [(dihydroindenyl)oxy] alkanoic acid (DIOA), the neuroprotective effects induced by propofol postconditioning were reversed. Our study indicated that propofol postconditioning increased the expression of KCC2 in inhibitory GABAergic interneurons, thus providing acute neuroprotection to rats who had undergone cerebral I/R injury.

  8. Oxy-fuel technology - Rebox flameless - for reheating and annealing furnaces to increase capacity and reduce operation costs - industrial results; Tecnologia oxi-combustivel - Rebox 'flameless' - em fornos de reaqucimento e recozimento par aumento da capacidade produtiva e reducao dos custos energeticos - resultados industriais

    Energy Technology Data Exchange (ETDEWEB)

    Kfouri, Carlos Eduardo [The Linde Group, Munich (Germany). Iron Foundry and Steel; Nunes, Paulo Rogerio [The Linde Group, Munich (Germany). Metalurgia; Lugnet, Anders [The Linde Group, Munich (Germany). Steel Application Development; Scheele, Joachim von [The Linde Group, Munich (Germany). Metals and Glass Industries

    2010-07-01

    Most steel producers need solutions for higher production throughput in their reheat and annealing furnaces. The goals are to sell more and to improve utilization of investments in existing rolling mills and annealing operations, but also to facilitate the possible restructuring of business and to better manage peak volume demand. Additional throughput capacity also allows for repair and maintenance activities. Removing the nitrogen ballast from the combustion and heat transfer process improves furnace operation drastically. It has in over 120 all Rebox oxy fuel installations been reported that if replacing the combustion air with industrial grade oxygen, that furnace throughput can be boosted by up to 50%, and fossil fuel consumption cut by 50%. It facilitates the use of low-grade fuels since the necessary high flame temperatures can be achieved. Rebox is compact and powerful for a cost-effective retrofit in an existing or new furnace. It complies with ever-stricter requirements for emissions of CO{sub 2} and NO{sub x}. (author)

  9. Crystal structure of tri-aqua-(1,10-phen-anthroline-κ(2) N,N')(2,4,5-tri-fluoro-3-meth-oxy-benzoato-κO (1))cobalt(II) 2,4,5-tri-fluoro-3-meth-oxy-benzoate.

    Science.gov (United States)

    Sun, Junshan

    2014-11-01

    The title salt, [Co(C8H4F3O3)(C12H8N2)(H2O)3](C8H4F3O3), was obtained under solvothermal conditions by the reaction of 2,4,5-tri-fluoro-3-meth-oxy-benzoic acid with CoCl2 in the presence of 1,10-phenanthroline (phen). The Co(II) ion is octa-hedrally coordinated by two N atoms [Co-N = 2.165 (2) and 2.129 (2) Å] from the phen ligand, by one carboxyl-ate O atom [Co-O = 2.107 (1) Å] and by three O atoms from water mol-ecules [Co-O = 2.093 (1), 2.102 (1) and 2.114 (1) Å]. The equatorial positions of the slightly distorted octa-hedron are occupied by the N atoms, the carboxyl-ate O and one water O atom. An intra- and inter-molecular O-H⋯O hydrogen-bonding network between the water-containing complex cation and the organic anion leads to the formation of ribbons parallel to [010].

  10. Oxidation stability of biodiesel fuels and blends using the Rancimat and PetroOXY methods. Effect of 4-allyl-2,6-dimethoxyphenol and catechol as biodiesel additives on oxidation stability.

    Science.gov (United States)

    Botella, Lucía; Bimbela, Fernando; Martín, Lorena; Arauzo, Jesús; Sánchez, José L

    2014-01-01

    IN THE PRESENT WORK, SEVERAL FATTY ACID METHYL ESTERS (FAME) HAVE BEEN SYNTHESIZED FROM VARIOUS FATTY ACID FEEDSTOCKS: used frying olive oil, pork fat, soybean, rapeseed, sunflower, and coconut. The oxidation stabilities of the biodiesel samples and of several blends have been measured simultaneously by both the Rancimat method, accepted by EN14112 standard, and the PetroOXY method, prEN16091 standard, with the aim of finding a correlation between both methodologies. Other biodiesel properties such as composition, cold filter plugging point (CFPP), flash point (FP), and kinematic viscosity have also been analyzed using standard methods in order to further characterize the biodiesel produced. In addition, the effect on the biodiesel properties of using 4-allyl-2,6-dimethoxyphenol and catechol as additives in biodiesel blends with rapeseed and with soybean has also been analyzed. The use of both antioxidants results in a considerable improvement in the oxidation stability of both types of biodiesel, especially using catechol. Adding catechol loads as low as 0.05% (m/m) in blends with soybean biodiesel and as low as 0.10% (m/m) in blends with rapeseed biodiesel is sufficient for the oxidation stabilities to comply with the restrictions established by the European EN14214 standard. An empirical linear equation is proposed to correlate the oxidation stability by the two methods, PetroOXY and Rancimat. It has been found that the presence of either catechol or 4-allyl-2,6-dimethoxyphenol as additives affects the correlation observed.

  11. Oxidation stability of biodiesel fuels and blends using the Rancimat and PetroOXY methods. Effect of 4-allyl-2,6-dimetoxiphenol and cathecol as biodiesel additives on oxidation stability

    Science.gov (United States)

    Botella, Lucía; Bimbela, Fernando; Martín, Lorena; Arauzo, Jesús; Sanchez, Jose Luis

    2014-07-01

    In the present work, several fatty acid methyl esters (FAME) have been synthesized from various fatty acid feedstocks: used frying olive oil, pork fat, soybean, rapeseed, sunflower and coconut. The oxidation stabilities of the biodiesel samples and of several blends have been measured simultaneously by both the Rancimat method, accepted by EN14112 standard, and the PetroOXY method, prEN16091 standard, with the aim of finding a correlation between both methodologies. Other biodiesel properties such as composition, cold filter plugging point (CFPP), flash point (FP) and kinematic viscosity have also been analyzed using standard methods in order to further characterize the biodiesel produced. In addition, the effect on the biodiesel properties of using 4-allyl-2,6-dimetoxiphenol and cathecol as additives in biodiesel blends with rapeseed and with soybean has also been analyzed. The use of both antioxidants results in a considerable improvement in the oxidation stability of both types of biodiesel, especially using cathecol. Adding cathecol loads as low as 0.05 % (m/m) in blends with soybean biodiesel and as low as 0.10 % (m/m) in blends with rapeseed biodiesel is sufficient for the oxidation stabilities to comply with the restrictions established by the European EN14214 standard.An empirical linear equation is proposed to correlate the oxidation stability by the two methods, PetroOXY and Rancimat. It has been found that the presence of either cathecol or 4-allyl-2,6-dimetoxiphenol as additives affects the correlation observed.

  12. Crystal structure of 3-{[4-(2-meth-oxy-phen-yl)piperazin-1-yl]meth-yl}-5-(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione.

    Science.gov (United States)

    Al-Alshaikh, Monirah A; Abuelizz, Hatem A; El-Emam, Ali A; Abdelbaky, Mohammed S M; Garcia-Granda, Santiago

    2016-02-01

    The title compound, C18H20N4O2S2, is a new 1,3,4-oxa-diazole and a key pharmacophore of several biologically active agents. It is composed of a meth-yl(thio-phen-2-yl)-1,3,4-oxa-diazole-2(3H)-thione moiety linked to a 2-meth-oxy-phenyl unit via a piperazine ring that has a chair conformation. The thio-phene ring mean plane lies almost in the plane of the oxa-diazole ring, with a dihedral angle of 4.35 (9)°. The 2-meth-oxy-phenyl ring is almost normal to the oxa-diazole ring, with a dihedral angle of 84.17 (10)°. In the crystal, mol-ecules are linked by weak C-H⋯S hydrogen bonds and C-H⋯π inter-actions, forming layers parallel to the bc plane. The layers are linked via weak C-H⋯O hydrogen bonds and slipped parallel π-π inter-actions [inter-centroid distance = 3.6729 (10) Å], forming a three-dimensional structure. The thio-phene ring has an approximate 180° rotational disorder about the bridging C-C bond.

  13. A kryptoracemic salt: 2-{[2,8-bis-(tri-fluoro-meth-yl)quinolin-4-yl](hy-droxy)meth-yl}piperidin-1-ium (+)-3,3,3-tri-fluoro-2-meth-oxy-2-phenyl-propanoate.

    Science.gov (United States)

    Wardell, James L; Wardell, Solange M S V; Tiekink, Edward R T

    2016-06-01

    The asymmetric unit of the title salt, C17H17F6N2O(+)·C10H8F3O3 (-), comprises two piperidin-1-ium cations and two carboxyl-ate anions. The cations, each having an l-shaped conformation owing to the near orthogonal relationship between the quinolinyl and piperidin-1-ium residues, are pseudo-enanti-omeric. The anions have the same absolute configuration but differ in the relative orientations of the carboxyl-ate, meth-oxy and benzene groups. Arguably, the most prominent difference between the anions occurs about the Cq-Om bond as seen in the Cc-Cq-Om-Cm torsion angles of -176.1 (3) and -67.1 (4)°, respectively (q = quaternary, m = meth-oxy and c = carboxyl-ate). The presence of Oh-H⋯Oc and Np-H⋯Oc hydrogen bonds leads to the formation of a supra-molecular chain along the a axis (h = hy-droxy and p = piperidin-1-ium); weak intra-molecular Np-H⋯Oh hydrogen bonds are also noted. Chains are connected into a three-dimensional architecture by C-H⋯F inter-actions. Based on a literature survey, related mol-ecules/cations adopt a uniform conformation in the solid state based on the letter L.

  14. 增压富氧燃烧与捕集CO2电站的经济性分析%Economic Analysis of the Power Station with Pressurized Oxy-fuel Combustion and CO2 Capture

    Institute of Scientific and Technical Information of China (English)

    阎维平; 董静兰; 任海锋

    2012-01-01

    以300MW燃煤锅炉汽轮发电机组为研究对象,计算了其在6~8MPa压力下增压富氧燃烧的经济性,并与常压富氧燃烧下的经济性进行了对比分析.结果表明:由于系统压力的提高,烟气中水蒸气的凝结热得以回收,用于加热汽轮机低温凝结水,减少汽轮机抽汽,使汽轮机出力增加,电厂的毛输出功率接近320MW;增压富氧燃烧的空气深冷分离制氧(ASU)功耗大大增加,占毛输出功率的26%,而烟气压缩(CPU)的功耗大大降低,约为毛输出功率的0.2%;综合考虑电站其他辅机功耗后,6~8MPa下增压富氧燃烧的电厂净效率比常压富氧燃烧下提高了4.5%.与常压富氧燃烧发电机组相比,增压富氧燃烧在CO2的捕集、压缩液化与封存(CCS)技术中的经济性明显提高.%Taking the 300 MW sub-critical turbine-generator unit as an object of study, an economic calcu lation was carried out for the unit with 6-8 MPa pressurized oxy-fuel combustion, of which the result was compared with that of the atmospheric oxy-fuel combustion. Results show that under pressurized oxy-fuel combustion condition, the gross unit power output reaches 320 MW due to the increased systematic pressure, the recovered latent heat in flue gas steam, which is to be used to heat low-temperature condensate ,and the increased turbine output resulted from reduced steam extraction; the power consumption of air separation unit rises greatly, accounting for about 26% of the gross power, and that of the purification and compression unit reduces sharply, accounting for about 0.2 % of the gross power; considering other auxiliary power consumptions, the overall net efficiency of unit with 6-8 MPa pressurized oxy-fuel combustion may be improved by 4.5 %, compared with that of the atmospheric oxy-fuel combustion, indicating obvious economical effect in the application of carbon capture and storage technology.

  15. DEGRADATION OF OXO-BIODEGRADABLE AND USUAL PLASTIC PACKAGING = DEGRADAÇÃO DE EMBALAGENS PLÁSTICAS OXI-BIODEGRADÁVEIS E COMUNS

    Directory of Open Access Journals (Sweden)

    Caio da Silva Miranda

    2015-11-01

    Full Text Available The mostly packaging Urban Solid Waste are bought or acquired in commercial establishments. This study was possible to analyze the degradation of packaging urban solid waste, checking which packages used by consumers cause for less impact on the environment. The experimental conditions adopted in this present study are due to the variation of temperature, time, amount of leachate and/ or rainwater. Therefore, with the experiments it can be seen that variation of nutrients matches the variation of microorganism in the filtrate of rainwater and leachate. The samples immersed in rainwater and leachate obtained opposite results among themselves. The samples have degraded more at the high temperatures. In a short exposure time have been shown to hardly relevant to the degradation. In general the oxo-biodegradable packaging get showed similar results with the usual packaging. = A maioria das embalagens plásticas é sacola comprada ou recebida gratuitamente de estabelecimentos comerciais. No presente trabalho foi possível analisar a degradação de embalagens plásticas oxi-biodegradáveis e as comuns, verificando quais delas utilizadas pelos consumidores causam menos impacto ao meio ambiente. As condições experimentais adotadas no presente trabalho foram em função da variação de temperatura, tempo, na presença de chorume e de água de chuva. Com a realização dos experimentos pode-se observar que uma variação de nutrientes condisse com a variação de micro-organismos nos filtrados de água da chuva e do chorume. As amostras imersas em água da chuva e no chorume obtiveram efeitos inversos entre si. As amostras degradaram mais em altas temperaturas. Em pequeno período de exposição, o tempo se mostrou pouco relevante para a degradação. De uma forma geral, as embalagens oxibiodegradáveis apresentaram resultados parecidos com as embalagens comuns.

  16. Tuning the properties of visible-light-responsive tantalum (oxy)nitride photocatalysts by non-stoichiometric compositions: A first-principles viewpoint

    KAUST Repository

    Harb, Moussab

    2014-01-01

    Finding an ideal photocatalyst for achieving efficient overall water splitting still remains a great challenge. By applying accurate first-principles quantum calculations based on DFT with the screened non-local hybrid HSE06 functional, we bring rational insights at the atomic level into the influence of non-stoichiometric compositions on essential properties of tantalum (oxy)nitride compounds as visible-light-responsive photocatalysts for water splitting. Indeed, recent experiments show that such non-stoichiometry is inherent to the nitridation methods of tantalum oxide with unavoidable oxygen impurities. We considered here O-enriched Ta3N5 and N-enriched TaON materials. Although their structural parameters are found to be very similar to those of pure compounds and in good agreement with available experimental studies, their photocatalytic features for visible-light-driven overall water splitting reactions show different behaviors. Further partial nitration of TaON leads to a narrowed band gap, but partially oxidizing Ta3N5 causes only subtle changes in the gap. The main influence, however, is on the band edge positions relative to water redox potentials. The pure Ta3N5 is predicted to be a good candidate only for H+ reduction and H2 evolution, while the pure TaON is predicted to be a good candidate for water oxidation and O2 evolution. Non-stoichiometry has here a positive influence, since partially oxidized tantalum nitride, Ta(3-x)N(5-5x)O5x (for x ≥ 0.16) i.e. with a composition in between TaON and Ta3N5, reveals suitable band edge positions that correctly bracket the water redox potentials for visible-light-driven overall water splitting reactions. Among the various explored Ta(3-x)N(5-5x)O5x structures, a strong stabilization is obtained for the configuration displaying a strong interaction between the O-impurities and the created Ta-vacancies. In the lowest-energy structure, each created Ta-vacancy is surrounded by five O-impurity species substituting

  17. Crystal structures of (±)-(1SR,5SR,6SR,7SR,10SR,11SR,13RS,14SR)-13-hy-droxy-7-meth-oxy-meth-oxy-11,15,18,18-tetra-methyl-3-oxo-2,4-dioxa-tetra-cyclo-[12.3.1.0(1,5).0(6,11)]octa-dec-15-en-10-yl benzoate, its 13-epimer and 13-one derivative.

    Science.gov (United States)

    Oishi, Takeshi; Fukaya, Keisuke; Yamaguchi, Yu; Sugai, Tomoya; Watanabe, Ami; Sato, Takaaki; Chida, Noritaka

    2015-05-01

    The title compounds, C29H38O8·0.25C5H12, (A), C29H38O8, (B), and C29H36O8, (C), are tetra-cyclic benzoates possessing a taxane skeleton with a fused dioxolane ring as the core structure. In the asymmetric unit of (A), there are two independent benzoate mol-ecules (A and A') and a half mol-ecule of solvent pentane disordered about an inversion center. The mol-ecular conformations of (A), (B) and (C) are similar except for the flexible meth-oxy-meth-oxy group. The cyclo-hexane, cyclo-hexene and central cyclo-octane rings adopt chair, half-chair and chair-chair (extended crown) forms, respectively. The dioxolane rings are essentially planar, while the dioxolane ring of A' is slightly twisted from the mean plane. In the crystal of (A), inter-molecular O-H⋯O, C-H⋯O and C-H⋯π inter-actions link the independent benzoates alternately, forming a chain structure. In the crystals of (B) and (C), mol-ecules are linked through O-H⋯O and C-H⋯π inter-actions, and C-H⋯O hydrogen bonds, respectively, into similar chains. Further, weak inter-molecular C-H⋯O inter-actions connect the chains into a three-dimensional network in (A) and a sheet in (B), whereas no other interactions are observed for (C).

  18. A Convenient Method for Synthesis of Novel Cyclic Ethers (1R, 2R,3R, 5S, 7S, 9R, 12R)-3-(t-Butyldimethylsilyl)oxy-7-methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane

    Institute of Scientific and Technical Information of China (English)

    Jie YAN; Min ZHU

    2005-01-01

    Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7-methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyridine. A plausible mechanism was hypothesized.

  19. Near-infrared oxymeter biosensor prototype for non-invasive in vivo analysis of rat brain oxygenation: effects of drugs of abuse

    Science.gov (United States)

    Crespi, F.; Donini, M.; Bandera, A.; Congestri, F.; Formenti, F.; Sonntag, V.; Heidbreder, C.; Rovati, L.

    2006-07-01

    The feasibility of non-invasive analysis of brain activities was studied in the attempt to overcome the major limitation of actual in vivo methodologies, i.e. invasiveness. Optic fibre probes were used as the optical head of a novel, highly sensitive near-infrared continuous wave spectroscopy (CW-NIR) instrument. This prototype was designed for non-invasive analysis of the two main forms of haemoglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb), chromophores present in biological tissues. It was tested in peripheral tissue (human gastrocnemius muscle) and then reset to perform the measurement on rat brain. In animal studies, the optical head was firmly placed using stereotaxic apparatus upon the sagittal line of the head of anaesthetized adult rats, without any surgery. Then pharmacological treatments with saline (300 µl s.c.) amphetamine (2 mg kg-1) or nicotine (0.4 mg kg-1) were performed. Within 10-20 min amphetamine substantially increased HbO2 and reduced Hb control levels. Nicotine produced a rapid initial increase followed by a decrease in HbO2. In contrast to amphetamine, nicotine treatment also reduced Hb and blood volume. These results support the capacity of our CW-NIR prototype to measure non-invasively HbO2 and Hb levels in the rat brain, that are markers of the degree of tissue oxygenation, thus providing an index of blood levels and therefore of brain metabolism.

  20. Heat Transfer Characteristic in Oxy-fuel Circulating Fluidized Bed Boiler%富氧燃烧循环流化床锅炉炉内传热特性

    Institute of Scientific and Technical Information of China (English)

    王春波; 侯伟军; 陈传敏; 霍志红

    2011-01-01

    针对富氧燃烧循环流化床锅炉(circulating fluidized bed boiler,CFBB)炉内传热特性进行了研究。考虑气体辐射对传热系数的影响,建立了CFBB富氧燃烧下的传热模型。以一台440t/h循环流化床锅炉为例,通过模型分析了炉内传热情况,并和空气燃烧模式下的传热特性进行比较。进行了氧气浓度在30%、50%、70%气氛下的CFBB炉膛概念性设计。在循环流化床锅炉炉内传热中,灰占主导作用,烟气成分变化对传热系数影响不大。氧气浓度越高,越有必要设置外置换热器来维持炉膛正常运行。%The heat transfer in oxy-fuel circulating fluidized bed boiler (CFBB) was investigated. A model which considers the influence of gases radiation on heat transfer coefficient was set. Take a 440t/h CFBB for example, the heat transfer in furnace was calculated and the results were compared with air-fired CFBB. The model shows the heat transfer coefficient is not be changed greatly in oxy-fuel combustion, because the heat transfer is dominated by the effect of particles, not depend on gases composition. The concept design of oxy-fuel CFBB was done at 30%, 50%, and 70% O2 concentration. It was found the higher concentration of oxygen the more necessary to set an external heat exchanger to keep a normal operation of the furnace.

  1. Contribution to the study of sorption mechanisms at solid-liquid interfaces: application to the cases of apatites and oxy-hydroxides; Contribution a l'etude des mecanismes de sorption aux interfaces solide-liquide: application aux cas des apatites et des oxy-hydroxydes

    Energy Technology Data Exchange (ETDEWEB)

    Duc, M

    2002-11-15

    Sorption-desorption phenomena play an important role in the transport of toxic and radioactive elements in surface and underground water in contact with solid matter. Selenium, which is one of the long-lived radionuclides present in radioactive waste, is characterized by several oxidation states and by anionic species in aqueous solutions. In order to predict its transport, we need a good knowledge of its sorption processes. We have studied the sorption of Se(IV) and Se(VI) on two types of solids present in natural media or which have been proposed as additives to active barriers: hydroxy-apatites, fluoro-apatite and iron oxi-hydroxides (goethite and hematite). Sorption mechanisms have been studied through an approach including several different and complementary methods: titrimetry, zeta-metry, scanning and transmission electron microscopy, infrared spectroscopy, X-ray diffraction, X-ray photo electron spectroscopy, etc... Results showed that Se(VI) is much less sorbed than Se(VI) on both types of solids. For Se(IV) the sorption mechanisms are different for iron oxides and apatites. On oxides, sorption increases when pH decreases. It can be interpreted by a surface complexation model, essentially through an inner sphere complex (monodentate or bidentate). Modelling of Se sorption curves was performed after the determination of acido-basic properties of oxides. However, the determination of the intrinsic properties of oxides is disturbed by several parameters identified as impurities, evolution of the solid in solution, kinetic and solubility of the solid. For apatites, selenium sorption proceeds by exchange with superficial groups, with a maximum of fixation at approximately pH 8. Thanks to XPS measurements and the elaboration of a mathematical model, we could determine the depth of penetration of both selenium and cadmium on apatites. (author)

  2. Sn(II) oxy-hydroxides as potential adsorbents for Cr(VI)-uptake from drinking water: An X-ray absorption study

    Energy Technology Data Exchange (ETDEWEB)

    Pinakidou, Fani; Kaprara, Efthimia [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece); Katsikini, Maria; Paloura, Eleni C.; Simeonidis, Konstantinos [Aristotle University of Thessaloniki, School of Physics, Department of Solid State Physics, 54124 Thessaloniki (Greece); Mitrakas, Manassis, E-mail: manasis@eng.auth.gr [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece)

    2016-05-01

    The feasibility of implementing a Sn(II) oxy-hydroxide (Sn{sub 6}O{sub 4}(OH){sub 4}) for the reduction and adsorption of Cr(VI) in drinking water treatment was investigated using XAFS spectroscopies at the Cr-K-edge. The analysis of the Cr-K-edge XANES and EXAFS spectra verified the effective use of Sn{sub 6}O{sub 4}(OH){sub 4} for successful Cr(VI) removal. Adsorption isotherms, as well as dynamic Rapid Small Scale Test (RSSCT) in NSF water matrix showed that Sn{sub 6}O{sub 4}(OH){sub 4} can decrease Cr(VI) concentration below the upcoming regulation limit of 10 μg/L for drinking water. Moreover, an uptake capacity of 7.2 μg/mg at breakthrough concentration of 10 μg/L was estimated from the RSSCT, while the residual Cr(VI) concentration ranged at sub-ppb level for a significant period of the experiment. Furthermore, no evidence for the formation of Cr(OH){sub 3} precipitates was found. On the contrary, Cr(III)-oxyanions were chemisorbed onto SnO{sub 2}, which was formed after Sn(II)-oxidation during Cr(VI)-reduction. Nevertheless, changes in the type of Cr(III)-inner sphere complexes were observed after increasing surface coverage: Cr(III)-oxyanions preferentially sorb in a geometry which combines both bidentate binuclear ({sup 2}C) and monodentate ({sup 1}V) geometries, at the expense of the present bidentate mononuclear ({sup 2}E) contributions. On the other hand, the pH during sorption does not affect the adsorption mechanism of Cr(III)-species. The implementation of Sn{sub 6}O{sub 4}(OH){sub 4} in water treatment technology combines the advantage of rapidly reducing a large amount of Cr(VI) due to donation of two electrons by Sn(II) and also the strong chemisorption of Cr(III) in a combination of the {sup 2}C and {sup 1}V configurations, which enhances the safe disposal of spent adsorbents. - Highlights: • Effective Cr(VI) removal from drinking water by Sn{sub 6}O{sub 4}(OH){sub 4} • Sn{sub 6}O{sub 4}(OH){sub 4} transformation to SnO{sub 2} after Cr

  3. Near-Zero Emissions Oxy-Combustion Flue Gas Purification Task 3: SOx/NOx/Hg Removal for Low Sulfur Coal

    Energy Technology Data Exchange (ETDEWEB)

    Zanfir, Monica; Solunke, Rahul; Shah, Minish

    2012-06-01

    The goal of this project was to develop a near-zero emissions flue gas purification technology for existing PC (pulverized coal) power plants that are retrofitted with oxycombustion technology. The objective of Task 3 of this project was to evaluate an alternative method of SOx, NOx and Hg removal from flue gas produced by burning low sulfur coal in oxy-combustion power plants. The goal of the program was to conduct an experimental investigation and to develop a novel process for simultaneously removal of SOx and NOx from power plants that would operate on low sulfur coal without the need for wet-FGD & SCRs. A novel purification process operating at high pressures and ambient temperatures was developed. Activated carbon's catalytic and adsorbent capabilities are used to oxidize the sulfur and nitrous oxides to SO{sub 3} and NO{sub 2} species, which are adsorbed on the activated carbon and removed from the gas phase. Activated carbon is regenerated by water wash followed by drying. The development effort commenced with the screening of commercially available activated carbon materials for their capability to remove SO{sub 2}. A bench-unit operating in batch mode was constructed to conduct an experimental investigation of simultaneous SOx and NOx removal from a simulated oxyfuel flue gas mixture. Optimal operating conditions and the capacity of the activated carbon to remove the contaminants were identified. The process was able to achieve simultaneous SOx and NOx removal in a single step. The removal efficiencies were >99.9% for SOx and >98% for NOx. In the longevity tests performed on a batch unit, the retention capacity could be maintained at high level over 20 cycles. This process was able to effectively remove up to 4000 ppm SOx from the simulated feeds corresponding to oxyfuel flue gas from high sulfur coal plants. A dual bed continuous unit with five times the capacity of the batch unit was constructed to test continuous operation and longevity. Full

  4. Rat Bite Fever

    Science.gov (United States)

    ... Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who ... ingestion of contaminated food or milk products (Haverhill fever). Most cases in the United States are caused ...

  5. SWEEP Project RAT

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Madsen, Søren; Petersen, L. B.

    This report presents the results from the design analyses made for the clustered suction caisson used as foundation for a Riser Access Tower (RAT). The RAT is intended built next to the K15-FA-1 Platform in the Dutch Sector of the North Sea....

  6. 增压富氧燃煤锅炉省煤器的设计与优化%Design and Optimization for Economizer of Pressurized Oxy-fuel Coal-fired Boilers

    Institute of Scientific and Technical Information of China (English)

    马凯; 阎维平; 高正阳; 许加庆

    2013-01-01

    以300 MW机组煤粉炉省煤器为例,对锅炉常压空气燃烧、常压富氧燃烧和5种不同增压(6 MPa)富氧燃烧方案下的锅炉对流受热面尺寸、烟气流量、烟气侧传热系数和压降等参数进行了计算和分析,根据基于(火用)经济性分析的单位换热量换热器总费用最小的原则确定省煤器的最佳设计结构.结果表明:与常压空气燃烧相比,常压富氧燃烧下烟气体积流量减小了28.5%,对流传热系数减小了11.5%;增压富氧燃烧下的烟气体积流量减小了98.82%,随着烟气流速的增大,受热面面积减小,烟气侧传热系数和压降增大;最佳方案中的烟气流速为1.54m/s时,单位换热量换热器总费用约为常压空气燃烧下的60%,烟气侧压降为582.65 Pa,烟道截面积仅为常压空气燃烧下的7.8%.%Taking the economizer of a 300 MW coal-fired boiler as an example, parameters such as the heating surface area, flue gas flow, gas-side heat-transfer coefficient and the pressure drop were calculated and analyzed respectively under conditions of atmospheric air combustion, atmospheric oxy-fuel combustion and pressurized (6 MPa) oxy-fuel combustion, after which an optimum structure was designed for the e-conomizer according to the principle of minimum total cost of heat-exchanger per unit heat-transfer rate based on exergy-economic analysis. Results show that compared with atmospheric air combustion, the flue gas volume flow rate and convection heat-transfer coefficient reduce respectively by 28. 5% and 11. 5% under atmospheric oxy-fuel combustion; under the condition of pressurized oxy-fuel combustion, the flue gas volume flow rate is 98. 82% lower than that of atmospheric air combustion, while both the gas-side heat-transfer coefficient and pressure drop increase and the heating surface area decreases with the rise of flue gas flow. Among all the given schemes, the flue gas velocity in optimal scheme is 1. 54 m/s, when the gas

  7. Crystal structure of 4-{[(2,4-di­hydroxy­benzyl­idene)amino]­meth­yl}cyclo­hexane­carb­oxy­lic acid

    Science.gov (United States)

    Danish, Muhammad; Akbar, Saba; Tahir, Muhammad Nawaz; Butt, Rabia Ayub; Ashfaq, Muhammad

    2015-01-01

    In the title compound, C15H19NO4, the cyclo­hexyl ring adopts a chair conformation with both exocyclic C—C bonds in equatorial orientations. The dihedral angle between the basal plane of cyclo­hexyl ring and the 2,4-di­hydroxy­benzaldehyde moiety is 84.13 (13)°. An intra­molecular O—H⋯N hydrogen bonds closes an S(6) ring. In the crystal, Oc—H⋯Op (c = carb­oxy­lic acid, p = phenol) hydrogen bonds link the mol­ecules into [100] C(13) chains whereas an Op—H⋯Oc hydrogen bond generates [101] C(15) chains. Together, these bonds generate (010) sheets incorporating R 2 2(20) loops. Weak C—H⋯O and C—H⋯π inter­actions also occur. PMID:26870569

  8. Crystal structure and Hirshfeld surface analysis of 1-carb-oxy-2-(3,4-di-hydroxy-phen-yl)ethan-1-aminium bromide 2-ammonio-3-(3,4-di-hydroxy-phen-yl)propano-ate.

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-11-01

    In the title mol-ecular salt, C9H12NO4(+)·Br(-)·C9H11NO4, one of the dopa mol-ecules is in the cationic form in which the α-amino group is protonated and the α-carb-oxy-lic acid group is uncharged, while the second dopa mol-ecule is in the zwitterion form. The Br(-) anion occupies a special position and is located on a twofold rotation axis. The two dopa mol-ecules are inter-connected by short O-H⋯O hydrogen bonds. In the crystal, the various units are linked by O-H⋯O, N-H⋯Br and N-H⋯O hydrogen bonds, forming a three-dimensional framework. The title compound was refined as an inversion twin with an absolute structure parameter of 0.023 (8).

  9. Separation of Tea Catechin Oxy-polymers by High Performance Liquid Chromatography%高效液相色谱法分离茶儿茶素氧化聚合物

    Institute of Scientific and Technical Information of China (English)

    李春美; 谢笔钧

    2001-01-01

    Tea catechin oxy-polymers were obtained by oxidizing tea catechinwith H2O2 and their isolation conditions of HPLC were studied. MS showed that their molecular weight range from 906.4 to 1962.4, which suggested that they might be dimer to pentamer of EGCG; Isocratic and linear gradient elution could not separate them from each other, but a method of combining linear and step gradients elution could separate them from each other. This HPLC method might provide a new way to separate oxy-polymers of catechin.%采用H2O2氧化以EGCG为主的儿茶素,并将所得的氧化产物进行了MS分析和HPLC分离。结果表明所得氧化产物主要为儿茶素的二至五聚体;一般的等度洗脱和线性梯度洗脱不能使儿茶素氧化聚合物各组分分离,往流动相中添加微量EDTA或乙酸铵并采用线性梯度和阶段梯度相结合的洗脱模式既可使氧化聚合物同小分子的儿茶素分开,也可使氧化聚合物各组分基本分离。这为儿茶素氧化聚合物的制取及分离提供了一条新思路。

  10. Oxidation stability of biodiesel fuels and blends using the Rancimat and PetroOXY methods. Effect of 4-allyl-2,6-dimetoxiphenol and cathecol as biodiesel additives on oxidation stability

    Directory of Open Access Journals (Sweden)

    Lucía eBotella

    2014-07-01

    Full Text Available In the present work, several fatty acid methyl esters (FAME have been synthesized from various fatty acid feedstocks: used frying olive oil, pork fat, soybean, rapeseed, sunflower and coconut. The oxidation stabilities of the biodiesel samples and of several blends have been measured simultaneously by both the Rancimat method, accepted by EN14112 standard, and the PetroOXY method, prEN16091 standard, with the aim of finding a correlation between both methodologies. Other biodiesel properties such as composition, cold filter plugging point (CFPP, flash point (FP and kinematic viscosity have also been analyzed using standard methods in order to further characterize the biodiesel produced. In addition, the effect on the biodiesel properties of using 4-allyl-2,6-dimetoxiphenol and cathecol as additives in biodiesel blends with rapeseed and with soybean has also been analyzed. The use of both antioxidants results in a considerable improvement in the oxidation stability of both types of biodiesel, especially using cathecol. Adding cathecol loads as low as 0.05 % (m/m in blends with soybean biodiesel and as low as 0.10 % (m/m in blends with rapeseed biodiesel is sufficient for the oxidation stabilities to comply with the restrictions established by the European EN14214 standard.An empirical linear equation is proposed to correlate the oxidation stability by the two methods, PetroOXY and Rancimat. It has been found that the presence of either cathecol or 4-allyl-2,6-dimetoxiphenol as additives affects the correlation observed.

  11. Novel GluN2B selective NMDA receptor antagonists: relative configuration of 7-meth-oxy-2-methyl-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ols.

    Science.gov (United States)

    Tewes, Bastian; Frehland, Bastian; Fröhlich, Roland; Wünsch, Bernhard

    2016-05-01

    The title compounds, C22H29NO2 (3) and C22H29NO2 (4) [systematic names: (1S*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol and (1R*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol, are diastereomers with the relative configuration of the adjacent hydroxyl and methyl groups at the seven-membered azepine ring being trans in (3) and cis in (4). In the crystals the orientation of these groups is -anti-periplanar (3) and +syn-clinal (4). In both cases, the crystals studied proved to be of a racemic mixture, with relative configurations (R*,S*)-3 and (R*,R*)-4. In both compounds, the seven-membered azepine ring has a chair-like conformation, and the 4-phenyl-butyl side chain adopts a extended conformation in (R*,S*)-3, but a twisted conformation in (R*,R*)-4. In the crystal of (S*,R*)-3, mol-ecules are linked via C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane. In the crystal of (R*,R*)-4, mol-ecules are linked via O-H⋯N hydrogen bonds, forming chains propagating along the c-axis direction. The chains are linked by C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane.

  12. Diaqua-bis{[1-hydr-oxy-2-(1H-imidazol-3-ium-1-yl)ethane-1,1-di-yl]bis-(hydrogen phospho-nato)}manganese(II).

    Science.gov (United States)

    Zhang, Zai-Chao; Li, Rong-Qing; Zhang, Yu

    2009-11-28

    In the title compound, [Mn(C(5)H(9)N(2)O(7)P(2))(2)(H(2)O)(2)], the Mn(II) atom (site symmetry ) is coordinated by four phos-pho-n-ate O atoms from a pair of partially deprotonated 1-hydr-oxy-2-(imidazol-3-yl)ethane-1,1-bis-phophonic acid ligands (imhedpH(3) (-)) and two water mol-ecules, resulting in a slightly distorted trans-MnO(6) octa-hedral geometry for the metal ion. In the ligands, the imidazole units are protonated and two of the hydr-oxy O atoms of the phospho-nate groups are deprotonated and chelate the Mn(II), thus forming the neutral mol-ecule of the title compound. The two protonated O atoms within the phospho-nate groups of one imhedpH(3) (-) ligand act as hydrogen-bond acceptors for a bifurcated hydrogen bond originating from the coordinated water mol-ecule. The phospho-nate units of neigboring mol-ecules are connected with their equivalents in neighboring mol-ecules via two types of inversion-symmetric hydrogen-bonding arrangements with four and two strong O-H⋯O hydrogen bonds, respectively. The two inter-actions connect mol-ecules into infinite chains along [111] and [110], in combination forming a tightly hydrogen-bonded three-dimensional supra-molecular network. This network is further stabilized by additional hydrogen bonds between the protonated imidazole units and one of the coordinated P-O O atoms and by additional O-H⋯O hydrogen bonds between the water mol-ecules and the P=O O atoms of neigboring mol-ecules.

  13. Development of novel CO{sub 2}-stable oxygen permeable dual phase membranes for CO{sub 2} capture in an oxy-fuel process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Huixia

    2012-07-19

    The combustion of fossil fuels in power stations with pure oxygen following the oxy-fuel process allows the Sequestration of CO{sub 2}. The pure oxygen needed can be separated from air by oxygen transporting ceramics like single phase perovskites. However, most of the so far developed single phase perovskites have stability problems in a CO{sub 2} containing atmosphere. Dual phase membranes are micro-scale mixtures of an electron conducting phase and an oxygen ion conducting phase and their compositions can be tailored according to practical requirements, which are considered to be promising substitutes for the single phase perovskite materials. In my thesis the issues of phase stability for perovskite-type material with the common composition Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 3-{delta}} (BSCF) as weil as the development of a series of novel CO{sub 2}-stable dual phase membranes were studied. In Chapter 2, the phase stability and permeation behavior of a dead-end BSCF tube membrane in high-purity oxygen at temperatures below 750 C, were elucidated using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS), high-angle annular dark-field (HAADF) and scanning transmission electron microscopy (STEM). lt was found that parts of the cubic perovskite BSCF transformed into a hexagonal perovskite Ba{sub 0.5{+-}x}Sr{sub 0.5{+-}x}CoO{sub 3-{delta}} (x {approx} 0.1) and a trigonal mixed oxide Ba{sub 1-x}Sr{sub x}CO{sub 2-y}Fe{sub y}O{sub 5{+-}{delta}} (x {approx} 0.15, y {approx} 0.25) in high-purity oxygen at 750 C. On the other hand, it was found that the partial degradation of cubic BSCF perovskite at 750 C was more pronounced under the strongly oxidizing conditions on the oxygen supply (feed) side than on the oxygen release (permeate) side of the membrane. The structural instability of BSCF is attributed to an oxidation of cobalt from Co{sup 2+} to Co{sup 3+} and Co{sup 4+}, which exhibits an ionic radius that is too small to be tolerated by

  14. Development of novel CO{sub 2}-stable oxygen permeable dual phase membranes for CO{sub 2} capture in an oxy-fuel process

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Huixia

    2012-07-19

    The combustion of fossil fuels in power stations with pure oxygen following the oxy-fuel process allows the Sequestration of CO{sub 2}. The pure oxygen needed can be separated from air by oxygen transporting ceramics like single phase perovskites. However, most of the so far developed single phase perovskites have stability problems in a CO{sub 2} containing atmosphere. Dual phase membranes are micro-scale mixtures of an electron conducting phase and an oxygen ion conducting phase and their compositions can be tailored according to practical requirements, which are considered to be promising substitutes for the single phase perovskite materials. In my thesis the issues of phase stability for perovskite-type material with the common composition Ba{sub 0.5}Sr{sub 0.5}Co{sub 0.8}Fe{sub 3-{delta}} (BSCF) as weil as the development of a series of novel CO{sub 2}-stable dual phase membranes were studied. In Chapter 2, the phase stability and permeation behavior of a dead-end BSCF tube membrane in high-purity oxygen at temperatures below 750 C, were elucidated using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS), high-angle annular dark-field (HAADF) and scanning transmission electron microscopy (STEM). lt was found that parts of the cubic perovskite BSCF transformed into a hexagonal perovskite Ba{sub 0.5{+-}x}Sr{sub 0.5{+-}x}CoO{sub 3-{delta}} (x {approx} 0.1) and a trigonal mixed oxide Ba{sub 1-x}Sr{sub x}CO{sub 2-y}Fe{sub y}O{sub 5{+-}{delta}} (x {approx} 0.15, y {approx} 0.25) in high-purity oxygen at 750 C. On the other hand, it was found that the partial degradation of cubic BSCF perovskite at 750 C was more pronounced under the strongly oxidizing conditions on the oxygen supply (feed) side than on the oxygen release (permeate) side of the membrane. The structural instability of BSCF is attributed to an oxidation of cobalt from Co{sup 2+} to Co{sup 3+} and Co{sup 4+}, which exhibits an ionic radius that is too small to be tolerated by

  15. Rat-bite fever

    Science.gov (United States)

    Streptobacillary fever; Streptobacillosis; Haverhill fever; Epidemic arthritic erythema; Spirillary fever; Sodoku ... Rat-bite fever can be caused by 2 different bacteria, Streptobacillus moniliformis or Spirillum minus. Both of these are found in ...

  16. Smooth muscle pharmacology in the isolated virgin and pregnant rat uterus and cervix.

    Science.gov (United States)

    Darios, Emma S; Seitz, Bridget; Watts, Stephanie W

    2012-06-01

    Uterine smooth muscle function is established, but comparatively little is known about cervical smooth muscle pharmacology. We performed a proof-of-principle experiment that smooth muscle was expressed in the cervix in both virgin and pregnant rats, using the uterus as a comparator. We tested whether all tissues were pharmacologically responsive to contractile and relaxant agonists. Immunohistochemistry revealed the expression of smooth muscle α-actin in all tissues. The isolated tissue bath was used to measure isometric contractility of uterine strips and whole cervices from virgin and pregnant (day 11 ± 2) female Sprague-Dawley rats. We tested classic activators of uterine smooth muscle contraction and relaxation in both uterus and cervix. All tissues contracted to the depolarizing agent potassium chloride, prostaglandin F2α, muscarinic cholinergic agonist carbachol [2-[(aminocarbonxyl)oxy]-N,N,N-trimethylethanaminium chloride], and 5-hydroxytryptamine. Unlike other tissues, the pregnant cervix did not contract to oxytocin, but the oxytocin receptor was present. Both cervix and uterus (virgin and pregnant) had concentration-dependent, near-complete relaxation to the adrenergic agonist norepinephrine and adenylate cyclase activator forskolin [(3R,4aR,5S,6S,6aS,10S,10aR,10bS)-6,10-10b-trihydroxy-3,4a,7,10a-pentamethyl-1-oxo-3-vinyldodecahydro-1H-benzo[f] chroment-5-yl acetate]. The β-adrenergic receptor agonist isoproterenol was less potent in pregnant cervix versus virgin by ∼10-fold. All tissues, particularly the cervix, responded poorly to the nitric-oxide donor sodium nitroprusside, relaxing ∼20% maximally. These findings support the importance of smooth muscle in the cervix, the use of the isolated cervix in pharmacological studies, and a similarity between smooth muscle pharmacology of the nonpregnant uterus and cervix. This work highlights the unappreciated smooth muscle function of the cervix versus uterus and cervical changes in pharmacology during

  17. Crystal structure of the magnesium salt of the herbicide 2,4-D: penta­aqua­[(2,4-di­chloro­phenoxy)acetato-κO]magnesium (2,4-di­chloro­phen­oxy)acetate hemihydrate

    OpenAIRE

    2014-01-01

    In the crystal structure of the title magnesium salt of the phen­oxy herbicide (2,4-di­chloro­phen­oxy)acetic acid (2,4-D), [Mg(C8H5Cl2O3)(H2O)5](C8H5Cl2O3)·0.5H2O, the discrete cationic MgO6 complex unit comprises a carboxyl­ate O-donor from a monodentate 2,4-D anionic ligand and five water mol­ecules, resulting in a slightly distorted octa­hedral coordination sphere. The free 2,4-D anions are linked to the complex units through duplex water–carboxyl­ate O—H⋯O hydrogen bonds through the coor...

  18. Crystal structure and Hirshfeld surface analysis of 1-carb­oxy-2-(3,4-di­hydroxy­phen­yl)ethan-1-aminium chloride 2-ammonio-3-(3,4-di­hydroxy­phen­yl)propano­ate: a new polymorph of l-dopa HCl and isotypic with its bromide counterpart

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-01-01

    The title mol­ecular salt, C9H12NO4 +·Cl−·C9H11NO4, is isotypic with that of the bromide counterpart [Kathiravan et al. (2016 ▸). Acta Cryst. E72, 1544–1548]. The title salt is a second monoclinic polymorph of the l-dopa HCl structure reported earlier in the monoclinic space group P21 [Jandacek & Earle (1971 ▸). Acta Cryst. B27, 841–845; Mostad & Rømming (1974 ▸). Acta Chemica Scand. B28, 1161–1168]. In the title compound, monoclinic space group I2, one of the dopa mol­ecules has a positive charge with a protonated α-amino group and the α-carb­oxy­lic acid group uncharged, while the second dopa mol­ecule has a neutral charge, the α-amino group is protonated and the α-carb­oxy­lic acid is deprotonated. In the previously reported form, a single dopa mol­ecule is observed in which the α-amino group is protonated and the α-carb­oxy­lic acid group is uncharged. The invariant and variations of various types of inter­molecular inter­actions present in these two forms of dopa HCl structures are discussed with the aid of two-dimensional fingerprint plots. PMID:27840723

  19. Crystal structure and Hirshfeld surface analysis of 1-carb-oxy-2-(3,4-di-hydroxy-phen-yl)ethan-1-aminium chloride 2-ammonio-3-(3,4-di-hydroxy-phen-yl)propano-ate: a new polymorph of l-dopa HCl and isotypic with its bromide counterpart.

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-11-01

    The title mol-ecular salt, C9H12NO4(+)·Cl(-)·C9H11NO4, is isotypic with that of the bromide counterpart [Kathiravan et al. (2016 ▸). Acta Cryst. E72, 1544-1548]. The title salt is a second monoclinic polymorph of the l-dopa HCl structure reported earlier in the monoclinic space group P21 [Jandacek & Earle (1971 ▸). Acta Cryst. B27, 841-845; Mostad & Rømming (1974 ▸). Acta Chemica Scand. B28, 1161-1168]. In the title compound, monoclinic space group I2, one of the dopa mol-ecules has a positive charge with a protonated α-amino group and the α-carb-oxy-lic acid group uncharged, while the second dopa mol-ecule has a neutral charge, the α-amino group is protonated and the α-carb-oxy-lic acid is deprotonated. In the previously reported form, a single dopa mol-ecule is observed in which the α-amino group is protonated and the α-carb-oxy-lic acid group is uncharged. The invariant and variations of various types of inter-molecular inter-actions present in these two forms of dopa HCl structures are discussed with the aid of two-dimensional fingerprint plots.

  20. 循环流化床高浓度富氧燃烧试验研究%Experimental Study on Oxy-fuel Combustion With High Oxygen Concentration in a Circulating Fluidized Bed

    Institute of Scientific and Technical Information of China (English)

    谭力; 李诗媛; 李伟; 寿恩广; 吕清刚

    2014-01-01

    In order to investigate the effects of combustion temperature and atmosphere on the combustion stability, CO2 concentration and gaseous pollutants emissions in flue gas, in a 0.1 MW circulating fluidized bed (CFB) oxy-fuel combustion facility, oxy-combustion experiments with Datong coal were carried out at O2/CO2 and O2/ recycled flue gas (RFG) atmosphere with high oxygen concentration. The test results show that when the oxygen concentration of the primary air ranges from 49.6%to 55.2%and that of the secondary air is in the range from 45.3%to 51.7%, the CFB oxy-fuel combustion facility maintains stably at O2/RFG atmosphere. In flue gas, CO2 concentration can reach above 90%, SO2 concentration is 87 to 197 mg/MJ, N2O concentration is 48 to 78 mg/MJ, and NO concentration is only 19 to 44 mg/MJ. Compared with the result of O2/CO2 combustion, the concentration of CO and SO2 increases to a certain degree, while N2O concentration decreases obviously, and NO concentration basically remains the same.%#在0.1 MW循环流化床富氧燃烧试验系统上,进行了大同烟煤在O2/再循环烟气(RFG)和O2/CO2配气下的高浓度富氧燃烧试验,研究燃烧温度和气氛对燃烧稳定性、烟气中CO2浓度和气体污染物排放的影响。研究结果表明,O2/RFG气氛下,在一次风氧气浓度为49.6%~55.2%、二次风氧气浓度为45.3%~51.7%范围内,循环流化床能够稳定运行,烟气中CO2浓度达到90%以上,SO2浓度为87~197 mg/MJ,N2O浓度为48~78 mg/MJ,NO仅为19~44 mg/MJ。与O2/CO2配气燃烧相比,O2/RFG燃烧时除NO浓度基本不变外,CO与SO2浓度均有一定程度的增加,而N2O浓度则明显降低。

  1. Effect of water on pyrolysis and combustion process of coal during oxy-coal combustion%水对氧煤燃烧方式下煤粉热解及燃烧过程的影响

    Institute of Scientific and Technical Information of China (English)

    罗嘉; 张曦; 吴望晨; 王超; 刘小伟

    2015-01-01

    为了探究湿式氧煤燃烧过程产生的高体积分数水对煤粉脱挥发分、煤焦气化、颗粒燃尽及 CO生成特性的影响,利用自行搭建的沉降炉系统,在0.2 s,0.3 s 和0.5 s 停留时间条件下分别进行了模拟烟气气氛下的煤粉热解和燃烧实验.其中,热解实验采用纯 N2气氛、纯 CO2气氛和CO2+水(不同体积分数比)气氛,燃烧实验则在此基础上分别加入了体积分数为5%,10%,21%和30%的 O2来替换气氛中的 N2或 CO2.结果表明:相较于空气燃烧,氧煤燃烧中的高体积分数CO2会抑制煤粉挥发分的析出,而高体积分数水的加入则会提高氧煤燃烧初期煤粉脱挥发分的速率,且在煤粉热解阶段,水和 CO2不会与煤焦发生气化反应;水在高氧体积分数、足够的停留时间条件下对煤粉燃尽率基本无影响,但会降低低氧体积分数条件下的煤粉燃尽率;水能够促进CO的氧化,从而降低炉内的CO体积分数.%To investigate the effect of high concentration water on coal volatilization,char gasification,char particle burnout and CO generation during wet oxy-coal combustion,the coal pyrolysis and combustion ex-periments were carried out in simulated flue gas atmospheres on a self-built drop tube furnace,with the particle residence time in the reactor of 0.2 s,0.3 s and 0.5 s.The pyrolysis tests were conducted in pure N2 atmosphere,pure CO2 atmosphere and CO2 with different concentrations of steam atmosphere.On this basis,the combustion tests adopt O2 with volume fraction of 5%,10%,21% and 30% to take place the N2 or CO2 in the pyrolysis atmospheres.the residence time of coal particles in the reactor during each test is 0.2 s,0.3 s and 0.5 s,respectively.The results indicate that,compared with air combustion,high concen-tration CO2 during oxy-coal combustion can inhibit the devolatilization of coal.The addition of high concen-tration H2 O during oxy-coal combustion can enhance the early stage

  2. Use of synchrotron XANES and Cr-doped coal to further confirm the vaporization of organically bound Cr and the formation of chromium(VI) during coal oxy-fuel combustion.

    Science.gov (United States)

    Chen, Juan; Jiao, Facun; Zhang, Lian; Yao, Hong; Ninomiya, Yoshihiko

    2012-03-20

    Through the use of synchrotron XANES and Cr-doped brown coal, extensive efforts have been made to clarify the volatility of organically bound Cr during oxy-fuel combustion and the mode of occurrence and leachability of Cr in resulting fly ashes. As the continuation of our previous study using raw coal, the Cr-doped coal has been tested in this study to improve the signal-to-noise ratio for Cr K-edge XANES spectra, and hence the accuracy for Cr(VI) quantification. As has been confirmed, the abundant CO(2) as a balance gas for oxy-firing has the potential to inhibit the decomposition of organically bound Cr, thereby favoring its retention in solid ash. It also has the potential to promote the oxidation of Cr(III) to Cr(VI) to a minor extent. Increasing the oxygen partial pressure, particularly in the coexistence of HCl in flue gas, favored the oxidation of Cr(III) into gaseous Cr(VI)-bearing species such as CrO(2)Cl(2). Regarding the solid impurities including Na(2)SO(4) and CaO, Na(2)SO(4) has proven to preferentially capture the Cr(III)-bearing species at a low furnace temperature such as 600 °C. Its promoting effect on the oxidation of Cr(III) to Cr(VI), although thermodynamically available at the temperatures examined here, is negligible in a lab-scale drop tube furnace (DTF), where the particle residence time is extremely short. In contrast, CaO has proven facilitating the capture of Cr(VI)-bearing species particularly oxychloride vapors at 1000 °C, forming Ca chromate with the formulas of CaCrO(4) and Ca(3)(CrO(4))(2) via a direction stabilization of Cr(VI) oxychloride vapor by CaO particle or an indirect oxidation of Cr(III) via the initial formation of Ca chromite. The fly ash collected from the combustion of Cr-doped coal alone has a lower water solubility (i.e., 58.7%) for its Cr(VI) species, due to the formation of Ba/Pb chromate and/or the incorporation of Cr(VI) vapor into a slagging phase which is water-insoluble. Adding CaO to coal increased the

  3. Influência do molibdênio em propriedades do metal de solda na soldagem molhada com eletrodos óxi-rutílicos Influence of molybdenum in metal weld properties in welding wet with oxy-rutillic electrodes

    Directory of Open Access Journals (Sweden)

    Luciana Ferreira Silva

    2013-06-01

    Full Text Available A técnica de soldagem subaquática molhada com eletrodos revestidos apresenta um crescente potencial de aplicação para reparos submarinos em elementos estruturais de unidades flutuantes de produção de petróleo (profundidade até 20 m. Porém, ela apresenta problemas tais como o maior risco de fissuração a frio e de formação acentuada de porosidade. O presente trabalho tem como objetivo melhorar a resistência mecânica do metal de solda de um eletrodo experimental do tipo oxi-rutílico. Foram estudadas as influências de adições de Mo (até 0,4% no metal de solda na microestrutura e em propriedades mecânicas. As soldas foram realizadas em simulador de soldagem subaquática em profundidade equivalente de 10m utilizando um sistema de soldagem por gravidade. As análises das micrografias mostrou que o aumento do teor de Mo no metal de solda diminui significantemente o tamanho médio de grão da região reaquecida de grãos finos. O aumento do teor de Mo no metal de solda resultou, ainda, em aumento do limite de resistência à tração sem perdas de tenacidade e ductilidade até aproximadamente 0,25%Mo.the underwater wet welding with coated electrodes technique is undergoing an important use growth in underwater repairs of oil production floating unit's structural elements (up to 20 m depth. However, it presents problems such as increased risk of cold cracking and sharp porosity formation. This work aims to improve the weld metal's mechanical strength through the addition of molybdenum to experimental oxy-rutilic type electrodes. Both the microstructure and the mechanical properties of weld metals were studied while electrodes would receive additional Mo (up to 0.4%. The welds were done using a gravity welding system placed in an underwater welding simulator with an equivalent depth of 10 m. Analyses of micrographics shown that the increased level of Mo in weld metal (a decreases significantly the average grain size of fine

  4. 4-((R)-2-{[6-((S)-3-Methoxypyrrolidin-1-yl)-2-phenylpyrimidine-4-carbonyl]amino}-3-phosphonopropionyl)piperazine-1-carboxylic Acid Butyl Ester (ACT-246475) and Its Prodrug (ACT-281959), a Novel P2Y12 Receptor Antagonist with a Wider Therapeutic Window in the Rat Than Clopidogrel.

    Science.gov (United States)

    Caroff, Eva; Hubler, Francis; Meyer, Emmanuel; Renneberg, Dorte; Gnerre, Carmela; Treiber, Alexander; Rey, Markus; Hess, Patrick; Steiner, Beat; Hilpert, Kurt; Riederer, Markus A

    2015-12-10

    Recent post hoc analyses of several clinical trials with P2Y12 antagonists showed the need for new molecules being fully efficacious as antiplatelet agents and having a reduced propensity to cause major bleeding. We have previously reported the discovery of the 2-phenylpyrimidine-4-carboxamide analogs as P2Y12 antagonists with nanomolar potency in the disease-relevant platelet aggregation assay in human plasma. Herein we present the optimization steps that led to the discovery of clinical candidate ACT-246475 (30d). The key step was the replacement of the carboxylic acid functionality by a phosphonic acid group which delivered the most potent molecules of the program. In addition, low in vivo clearance in rat and dog was achieved for the first time. Since the bioavailability of 30d was low in rat and dog, we developed the bis((isopropoxycarbonyl)oxy)methyl ester prodrug (ACT-281959, 45). Compound 30d showed efficacy in the rat ferric chloride thrombosis model when administered intravenously as parent or orally as its prodrug 45. Moreover, 30d displays a wider therapeutic window as compared to clopidogrel in the rat surgical blood loss model.

  5. 1-[(Anthracen-9-yl)carbon-yl]-2,7-di-meth-oxy-naphthalene: a chain-like structure composed of face-to-face type dimeric mol-ecular aggregates.

    Science.gov (United States)

    Siqingaowa; Tsumuki, Takehiro; Ogata, Kazuki; Yonezawa, Noriyuki; Okamoto, Akiko

    2016-12-01

    The asymmetric unit of the title compound, C27H20O3, contains two independent mol-ecules (A and B). The anthracene ring system is connected to the 2,7-di-meth-oxy-naphthalene core in a twisted manner, with dihedral angles of 86.38 (5) and 79.36 (8)°, respectively, for conformers A and B. In the crystal, face-to-face type dimeric mol-ecular aggregates of each conformer are observed. The dimer of conformer A is formed by two pairs of C-H⋯π inter-actions, and that of conformer B by a pair of (sp(2))C-H⋯O hydrogen bonds. The dimers of conformer A are linked to each other via a π-π stacking inter-action between the anthracene rings to form a chain along the b axis and the chains are aligned along the c axis, forming a sheet structure. The dimers of conformer B are connected to each other via a couple of C-H⋯π inter-actions to form a chain along the b axis. The chains are aligned along the c axis through (sp(2))C-H⋯O=C hydrogen bonds, forming a sheet parallel to the bc plane. The sheets of conformers A and B are alternately stacked along the a axis via two kinds of inter-molecular (sp(2))C-H⋯O=C hydrogen bonds.

  6. The Corrosion and Wear Performance of Microcrystalline WC-10Co-4Cr and Near-Nanocrystalline WC-17Co High Velocity Oxy-Fuel Sprayed Coatings on Steel Substrate

    Science.gov (United States)

    Saha, Gobinda C.; Khan, Tahir I.

    2010-11-01

    The study of near-nanocrystalline cermet composite coating was performed by depositing near-nanocrystalline WC-17Co powder using the high velocity oxy-fuel spraying technique. The WC-17Co powder consists of a core with an engineered near-nano-scale WC dispersion with a mean grain size 427 nm. The powder particle contains 6 wt pct of the ductile phase Co matrix mixed into the core to ensure that the reinforcing ceramic phase WC material is discontinuous to limit debridement during wear, while the remainder of the binding phase (11 wt pct) is applied as a coating on the powder particle to improve the ductility. The tribological properties of the coating, in terms of corrosion resistance, microhardness, and sliding abrasive wear, were studied and compared with those of an industrially standard microcrystalline WC-10Co-4Cr coating with a WC mean grain size 3 μm. Results indicated that the WC-17Co coating had superior wear and corrosion resistance compared to the WC-10Co-4Cr coating. The engineered WC-17Co powder with a duplex Co layer had prevented significant decarburization of the WC dispersion in the coating, thereby reducing the intersplat microporosity necessary for initiating microgalvanic cells. The improved wear resistance was attributed to the higher hardness value of the near-nanocrystalline WC-17Co coating.

  7. Syntheses, structures and photoluminescent properties of Zn(Ⅱ)/Co(Ⅱ) coordination polymers based on flexible tetracarboxylate ligand of 5,5‧-(butane-1,4-diyl)-bis(oxy)-di isophthalic acid

    Science.gov (United States)

    Gao, Yan-Peng; Guo, Le; Dong, Wei; Jia, Min; Zhang, Jing-Xue; Sun, Zhong; Chang, Fei

    2016-08-01

    Three new mixed-ligand metal-organic frameworks based on 5,5‧-(butane-1,4- diyl)-bis(oxy)-diisophthalic acid and transitional metal cations with the help of two ancillary bridging N-donor pyridyl and imidazole linkers, [Zn(L)0.5(4,4‧-bpy)]·2(H2O) (1), [M(L)0.5(bib)]·4(H2O) (M = Zn (2), Co (3)), (4,4‧-bpy=4,4‧-bipyridine, bib=1,4-bis (1H-imidazol-1-yl)-butane), have been synthesized under solvothermal conditions. Their structures and properties were determined by single-crystal and powder X-ray diffraction analyses, IR spectra, elemental analyses and thermogravimetric analyses (TGA). Compounds 1-3 display a 3D 3-fold interpenetrated frameworks linked by the L4- ligands, ancillary N-donor linkers and the free water molecules in the crystal lattice. Topological analysis reveals that 1-3 are a (4,4)-connected bbf topology net with the (64·82)(66) topology. The effects of the L4- anions, the N-donor ligands, and the metal ions on the structures of the coordination polymers have been discussed. Furthermore, luminescence properties and thermogravimetric properties of these compounds were investigated.

  8. Ash partitioning during the oxy-fuel combustion of lignite and its dependence on the recirculation of flue gas impurities (H{sub 2}O, HCl and SO{sub 2})

    Energy Technology Data Exchange (ETDEWEB)

    Facun Jiao; Juan Chen; Lian Zhang; Yajuan Wei; Yoshihiko Ninomiya; Sankar Bhattacharya; Hong Yao [Monash University, Clayton, Vic. (Australia). Department of Chemical Engineering

    2011-06-15

    Oxy-fuel combustion of a brown coal (i.e. lignite) has been carried out at 1000{sup o}C to experimentally examine the vaporisation of organically bound metals and the agglomeration of ash particles as a function of the concentration of gaseous impurities including H{sub 2}O, HCl and SO{sub 2} in about 27% O{sub 2} balanced with CO{sub 2}. The properties of bulk ash and individual metals were investigated intensively. Particularly, attention was paid to Na which is notorious for fouling and to organically bound Al which has been less studied. The results indicate that, the organically bound metals, although possessing a very low content in the raw coal, are vital for the agglomeration of ash particles, which are also highly sensitive to the loading of gas impurities in flue gas. HCl recirculation is the most crucial factor promoting the vaporisation of metals via chlorination. Apart from alkali metals, the organically bound Al and Ti were also vaporised noticeably. Recirculation of SO{sub 2} promoted the sulfation of Na to condense into liquid droplet which increased fine ash yield. Co-existence of bulk HCl and SO{sub 2} played a synergetic role in the sulfation of Na via an initial chlorination of the char-bound Na. In contrast, co-existence of steam with HCl and SO{sub 2} favored the formation of Na alumino-silicates, which are favorable for ash agglomeration. 34 refs., 15 figs., 3 tabs.

  9. Crystal structure of bis-(2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-meth-oxy-phenolato)manganese(IV) 0.39-hydrate.

    Science.gov (United States)

    Buvaylo, Elena A; Vassilyeva, Olga Yu; Skelton, Brian W

    2015-11-01

    The title compound, [Mn(C12H15NO5)2]·0.39H2O, is a 0.39 hydrate of the isostructural complex bis-(2-{[1,1-bis-(hy-droxy-meth-yl)-2-oxidoeth-yl]imino-meth-yl}-6-meth-oxy-phenolato)manganese(IV) that has previously been reported by Back, Oliveira, Canabarro & Iglesias [Z. Anorg. Allg. Chem. (2015), 641, 941-947], based on room-temperature data. The current structure that was determined at 100 K reveals a lengthening of the c cell parameter compared with the published one due to the incorporation of the partial occupancy water mol-ecule. The title compound crystallizes in the tetra-gonal chiral space group P41212; the neutral [Mn(IV)(C12H15NO5)2] mol-ecule is situated on a crystallographic C 2 axis. The overall geometry about the central manganese ion is octa-hedral with an N2O4 core; each ligand acts as a meridional ONO donor. The coordination environment of Mn(IV) at 100 K displays a difference in one of the two Mn-O bond lengths, compared with the room-temperature structure. In the crystal, the neutral mol-ecules are stacked in a helical fashion along the c-axis direction.

  10. 4-Hy-droxy-5-meth-oxy-N,1-dimethyl-2-oxo-N-[4-(tri-fluoro-meth-yl)phen-yl]-1,2-di-hydro-quinoline-3-carboxamide.

    Science.gov (United States)

    Akinboye, Emmanuel S; Butcher, Ray J; Yildirim, Sema Ozturk; Isaacs, John T

    2014-03-01

    The title compound, C20H17F3N2O4, named tasquinimod, is a second-generation oral quinoline-3-carboxamide analogue, which is currently in phase III clinical trials for the treatment of metastatic prostate cancer. The quinoline unit is almost planar (r.m.s. deviation of fitted atoms = 0.0075 Å). The carboxamide side chain, substituted at position 3, is tilted by 88.07 (7)° to the quinoline plane. Both the methyl and carbonyl groups of this carboxamide side chain are in a syn conformation. The 4-(tri-fluoro-meth-yl)phenyl plane is inclined at 50.62 (17)° to the plane of the carboxamide side chain, and at 87.14 (4)° to the plane of the quinoline ring system. The 4-hy-droxy H atom acts as a double proton donor in an intra-molecular hydrogen bond to the 5-position meth-oxy O atom and in an inter-molecular contact to the 2-oxo group, generating a chain along [010] in the crystal structure.

  11. In vitro anti-Candida activity and single crystal X-ray structure of ({(1E-[3-(1H-imidazol-1-yl-1-phenylpropylidene]amino}oxy(4-nitrophenylmethanone

    Directory of Open Access Journals (Sweden)

    Mohamed I. Attia

    2014-03-01

    Full Text Available Synthesis, characterization, and anti-Candida activity of ({(E-[3-(1H-imidazol-1-yl-1-phenylpropylidene]amino}oxy(4-nitrophenylmethanone (4 are repor-ted. Compound 4 showed anti-Candida albicans activity (MIC = 0.6862 µmol/mL being nearly 5-fold more potent than the gold standard antifungal drug, fluconazole (MIC ˃ 3.265 µmol/mL, on the clinical isolates of Candida albicans. Single crystal X-ray structure of the title compound 4 confirmed its assigned (E-configuration. The compound crystallizes in the triclinic, P-1 (no. 2, a = 6.4633 (1 Å, b = 11.1063 (2 Å, c = 12.9872 (2 Å, α = 67.650 (1°, β = 86.415 (1°, γ = 86.776 (1°, V = 860.01 (3Å3, Z = 2, R(F = 0.046, wR(F2 = 0.139, T = 296 K. The crystal structure is stabilized by weak intermolecular C—H•••O hydrogen interactions.

  12. The academic rat race

    DEFF Research Database (Denmark)

    Landes, Xavier; Andersen, Martin Marchman; Nielsen, Morten Ebbe Juul

    2012-01-01

    : an increased pressure to produce articles (in peer-reviewed journals) has created an unbalanced emphasis on the research criterion at the expense of the latter two. More fatally, this pressure has turned academia into a rat race, leading to a deep change in the fundamental structure of academic behaviour...

  13. Attachment behavior in rats

    NARCIS (Netherlands)

    Sigling, H.O.

    2009-01-01

    This thesis describes studies into the rat as an animal model for attachment, along the lines of Bowlby's attachment theory. First, the relation between attachment and human psychopathology is reviewed. The conclusion is that psychopathology is more frequent in insecure attached persons and that the

  14. Culturing rat hippocampal neurons.

    Science.gov (United States)

    Audesirk, G; Audesirk, T; Ferguson, C

    2001-01-01

    Cultured neurons are widely used to investigate the mechanisms of neurotoxicity. Embryonic rat hippocampal neurons may be grown as described under a wide variety of conditions to suit differing experimental procedures, including electrophysiology, morphological analysis of neurite development, and various biochemical and molecular analyses.

  15. {μ-2-[(3-Amino-2,2-dimethyl-prop-yl)imino-meth-yl]-6-meth-oxy-phenolato-1:2κ(5)O(1),O(6):N,N',O(1)}{2-[(3-amino-2,2-dimethyl-prop-yl)imino-meth-yl]-6-meth-oxy-phenolato-1κ(3)N,N',O(1)}-μ-azido-1:2κ(2)N:N-azido-2κN-methanol-2κO-dinickel(II).

    Science.gov (United States)

    Ghaemi, Akbar; Rayati, Saeed; Fayyazi, Kazem; Ng, Seik Weng; Tiekink, Edward R T

    2012-08-01

    Two distinct coordination geometries are found in the binuclear title complex, [Ni(2)(C(13)H(19)N(2)O(2))(2)(N(3))(2)(CH(3)OH)], as one Schiff base ligand is penta-dentate, coordinating via the anti-cipated oxide O, imine N and amine N atoms (as for the second, tridentate, ligand) but the oxide O is bridging and coordination also occurs through the meth-oxy O atom. The Ni(II) atoms are linked by a μ(2)-oxide atom and one end of a μ(2)-azide ligand, forming an Ni(2)ON core. The coordination geometry for the Ni(II) atom coordinated by the tridentate ligand is completed by the meth-oxy O atom derived from the penta-dentate ligand, with the resulting N(3)O(3) donor set defining a fac octa-hedron. The second Ni(II) atom has its cis-octa-hedral N(4)O(2) coordination geometry completed by the imine N and amine N atoms of the penta-dentate Schiff base ligand, a terminally coordinated azide N and a methanol O atom. The arrangement is stabilized by an intra-molecular hydrogen bond between the methanol H and the oxide O atom. Linear supra-molecular chains along the a axis are formed in the crystal packing whereby two amine H atoms from different amine atoms hydrogen bond to the terminal N atom of the monodentate azide ligand.

  16. The Year of the Rat

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Do you know what your Chinese sign of the zodiac is? According to the Chinese lunar calendar,every year corre- sponds to one of twelve animals(rat,ox,tiger,rabbit,dragon, snake,horse,sheep,monkey,rooster,dog and pig)and these animals are used to identify years. After the Lunar New Year in 2008 we enter the rat year. All those born in 1996,1984,1972.1960,1948,1936 or 1924, also have a rat as their sign.

  17. Hydrogen Sulfide Ameliorates Early Brain Injury Following Subarachnoid Hemorrhage in Rats.

    Science.gov (United States)

    Cui, Yonghua; Duan, Xiaochun; Li, Haiying; Dang, Baoqi; Yin, Jia; Wang, Yang; Gao, Anju; Yu, Zhengquan; Chen, Gang

    2016-08-01

    Increasing studies have demonstrated the neuroprotective effect of hydrogen sulfide (H2S) in central nervous system (CNS) diseases. However, the potential application value of H2S in the therapy of subarachnoid hemorrhage (SAH) is still not well known. This study was to investigate the potential effect of H2S on early brain injury (EBI) induced by SAH and explore the underlying mechanisms. The role of sodium hydrosulfide (NaHS), a donor of H2S, in SAH-induced EBI, was investigated in both in vivo and in vitro. A prechiasmatic cistern single injection model was used to produce experimental SAH in vivo. In vitro, cultured primary rat cortical neurons and human umbilical vein endothelial cells (HUVECs) were exposed to OxyHb at concentration of 10 μM to mimic SAH. Endogenous production of H2S in the brain was significantly inhibited by SAH. The protein levels of the predominant H2S-generating enzymes in the brain, including cystathionineb-synthase (CBS) and 3-mercaptopyruvate sulfur transferase (3MST), were also correspondingly reduced by SAH, while treatment with NaHS restored H2S production and the expressions of CBS and 3MST. More importantly, NaHS treatment could significantly attenuate EBI (including brain edema, blood-brain barrier disruption, brain cell apoptosis, inflammatory response, and cerebral vasospasm) after SAH. In vitro, H2S protects neurons and endothelial function by functioning as an antioxidant and antiapoptotic mediator. Our results suggest that NaSH as an exogenous H2S donor could significantly reduce EBI induced by SAH.

  18. Ang Ⅱ type 1 receptor expression in rat aorta exposed to chronic intermittent hypoxia: effects of p38MAPK and ERK1/2 signaling

    Institute of Scientific and Technical Information of China (English)

    SHANG Jin; YANG Yuan-yuan; GUO Xue-ling; LIU Hui-guo

    2013-01-01

    Background Obstructive sleep apnea is a frequent medical condition consisting of repetitive sleep-related episodes of upper air ways obstruction and can lead to hypertension.Ang Ⅱ type 1 receptor (AT1R) played important roles in hypertension since it binds with Ang Ⅱ,controlling salt-water and blood pressure homeostasis.This study explores rat aorta AT1R expression during intermittent hypoxia (IH) and the signaling pathways involved.Methods A rat model and a cell model used a BioSpherix-OxyCycler A84 system and a ProOx C21 system respectively.The arterial blood pressure was recorded by a Nihon Kohden Polygraph System.Immunohistochemic was used to focus and analyze the expression of AT1R in rat aorta.Real-time PCR and Western blotting were used to explore the signaling pathways that participated in AT1R expression.Results In this study,we found that chronic intermittent hypoxia (CIH) induced AT1R transcription which increased the blood pressure in rat aorta compared to normoxia and to sustained hypoxia.The AT1R protein expression in the aorta was similar to the real-time PCR results.We explored the signaling mechanisms involved in the AT1R induction in both rat aorta and the aortic endothelial cells by real-time PCR and Western blotting.Compared to normoxia,CIH increased ERK1 mRNA transcription but not ERK2 or p38MAPK in the aorta; whereas sustained hypoxia (SH) upregulated ERK2 but not ERK1 or p38MAPK mRNA.In cells,IH induced AT1R expression with ERK1/2 phosphorylation but reduced p38MAPKs phosphorylation,whereas SH induced only ERK1/2 phosphorylation.The ERK1/2 inhibitor PD98059 attenuated the IHinduced AT1R increase but the p38MAPK inhibitor SB203580 did not.Conclusions Our results indicate that CIH induced the elevation of rat blood pressure and aorta AT1R expression.Moreover,AT1R expression in IH and sustained hypoxia might be regulated by different signal transduction pathways,highlighting a novel regulatory function through ERK1/2 signaling in IH.

  19. Correlations of mutations in katG, oxyR-ahpC and inhA genes and in vitro susceptibility in Mycobacterium tuberculosis clinical strains segregated by spoligotype families from tuberculosis prevalent countries in South America

    Directory of Open Access Journals (Sweden)

    Suffys Philip N

    2009-02-01

    Full Text Available Abstract Background Mutations associated with resistance to rifampin or streptomycin have been reported for W/Beijing and Latin American Mediterranean (LAM strain families of Mycobacterium tuberculosis. A few studies with limited sample sizes have separately evaluated mutations in katG, ahpC and inhA genes that are associated with isoniazid (INH resistance. Increasing prevalence of INH resistance, especially in high tuberculosis (TB prevalent countries is worsening the burden of TB control programs, since similar transmission rates are noted for INH susceptible and resistant M. tuberculosis strains. Results We, therefore, conducted a comprehensive evaluation of INH resistant M. tuberculosis strains (n = 224 from three South American countries with high burden of drug resistant TB to characterize mutations in katG, ahpC and inhA gene loci and correlate with minimal inhibitory concentrations (MIC levels and spoligotype strain family. Mutations in katG were observed in 181 (80.8% of the isolates of which 178 (98.3% was contributed by the katG S315T mutation. Additional mutations seen included oxyR-ahpC; inhA regulatory region and inhA structural gene. The S315T katG mutation was significantly more likely to be associated with MIC for INH ≥2 μg/mL. The S315T katG mutation was also more frequent in Haarlem family strains than LAM (n = 81 and T strain families. Conclusion Our data suggests that genetic screening for the S315T katG mutation may provide rapid information for anti-TB regimen selection, epidemiological monitoring of INH resistance and, possibly, to track transmission of INH resistant strains.

  20. Influences of residual oxygen impurities, cubic indium oxide grains and indium oxy-nitride alloy grains in hexagonal InN crystalline films grown on Si(111) substrates by electron cyclotron resonance plasma-assisted molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Yodo, T.; Nakamura, T.; Kouyama, T. [Department of Electronics, Information and Communication Engineering, Osaka Institute of Technology, 5-16-1 Asahi-ku, Ohmiya, Osaka 535-8585 (Japan); Harada, Y. [Applied Physics, Osaka Institute of Technology, 5-16-1, Asahi-ku, Ohmiya, Osaka 535-8585 (Japan)

    2005-05-01

    We investigated the influences of residual oxygen (O) impurities, cubic indium oxide ({beta}-In{sub 2}O{sub 3}) grains and indium oxy-nitride (InON) alloy grains in 200 nm-thick hexagonal ({alpha})-InN crystalline films grown on Si(111) substrates by electron cyclotron resonance plasma-assisted molecular beam epitaxy. Although {beta}-In{sub 2}O{sub 3} grains with wide band-gap energy were formed in In film by N{sub 2} annealing, they were not easily formed in N{sub 2}-annealed InN films. Even if they were not detected in N{sub 2}-annealed InN films, the as-grown films still contained residual O impurities with concentrations of less than 0.5% ([O]{<=}0.5%). Although [O]{proportional_to}1% could be estimated by investigating In{sub 2}O{sub 3} grains formed in N{sub 2}-annealed InN films, [O]{<=}0.5% could not be measured by it. However, we found that they can be qualitatively measured by investigating In{sub 2}O{sub 3} grains formed by H{sub 2} annealing with higher reactivity with InN and O{sub 2}, using X-ray diffraction and PL spectroscopy. In this paper, we discuss the formation mechanism of InON alloy grains in InN films. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Crystal structure of 2-((1E)-{2-[bis-(2-methyl-benzyl-sulfan-yl)methyl-idene]hydrazin-1-yl-idene}meth-yl)-6-meth-oxy-phenol.

    Science.gov (United States)

    Yusof, Enis Nadia Md; Ravoof, Thahira Begum S A; Tahir, Mohamed Ibrahim Mohamed; Tiekink, Edward R T

    2015-04-01

    In the title compound, C25H26N2O2S2, the central CN2S2 atoms are almost coplanar (r.m.s. deviation = 0.0058 Å). One phenyl ring clearly lies to one side of the central plane, while the other is oriented in the plane but splayed. Despite the different relative orientations, the phenyl rings form similar dihedral angles of 64.90 (3) and 70.06 (3)° with the central plane, and 63.28 (4)° with each other. The benzene ring is twisted with respect to the central plane, forming a dihedral angle of 13.17 (7)°. The S2C=N, N-N and N-N=C bond lengths of 1.2919 (19), 1.4037 (17) and 1.2892 (19) Å, respectively, suggest limited conjugation over these atoms; the configuration about the N-N=C bond is E. An intra-molecular O-H⋯N hydrogen bond is noted. In the crystal, phen-yl-meth-oxy C-H⋯O and phen-yl-phenyl C-H⋯π inter-actions lead to supra-molecular double chains parallel to the b axis. These are connected into a layer via meth-yl-phenyl C-H⋯π inter-actions, and layers stack along the a axis, being connected by weak π-π inter-actions between phenyl rings [inter-centroid distance = 3.9915 (9) Å] so that a three-dimensional architecture ensues.

  2. Laughing rats are optimistic.

    Directory of Open Access Journals (Sweden)

    Rafal Rygula

    Full Text Available Emotions can bias human decisions- for example depressed or anxious people tend to make pessimistic judgements while those in positive affective states are often more optimistic. Several studies have reported that affect contingent judgement biases can also be produced in animals. The animals, however, cannot self-report; therefore, the valence of their emotions, to date, could only be assumed. Here we present the results of an experiment where the affect-contingent judgement bias has been produced by objectively measured positive emotions. We trained rats in operant Skinner boxes to press one lever in response to one tone to receive a food reward and to press another lever in response to a different tone to avoid punishment by electric foot shock. After attaining a stable level of discrimination performance, the animals were subjected to either handling or playful, experimenter-administered manual stimulation - tickling. This procedure has been confirmed to induce a positive affective state in rats, and the 50-kHz ultrasonic vocalisations (rat laughter emitted by animals in response to tickling have been postulated to index positive emotions akin to human joy. During the tickling and handling sessions, the numbers of emitted high-frequency 50-kHz calls were scored. Immediately after tickling or handling, the animals were tested for their responses to a tone of intermediate frequency, and the pattern of their responses to this ambiguous cue was taken as an indicator of the animals' optimism. Our findings indicate that tickling induced positive emotions which are directly indexed in rats by laughter, can make animals more optimistic. We demonstrate for the first time a link between the directly measured positive affective state and decision making under uncertainty in an animal model. We also introduce innovative tandem-approach for studying emotional-cognitive interplay in animals, which may be of great value for understanding the emotional

  3. Prevention of 3-methylcholanthrene-induced fibrosarcomas in rats pre-inoculated with endogenous rat retrovirus.

    OpenAIRE

    Fish, D C; Demarais, J T; Djurickovic, D B; Huebner, R J

    1981-01-01

    Weanling Fischer 344 rats received a single intraperitoneal injection of a 1000-fold concentrated preparation of endogenous nontransforming rat retrovirus. Ten days later, the rats were each given a single subcutaneous injection of 3-methylcholanthrene. The rats inoculated with the endogenous rat retrovirus were significantly protected against the development of cancer, whereas uninoculated rats and rats given one of several murine retroviruses or baboon retrovirus were not protected.

  4. Modification of oral absorption of oxyresveratrol using lipid based nanoparticles.

    Science.gov (United States)

    Sangsen, Yaowaporn; Wiwattanawongsa, Kamonthip; Likhitwitayawuid, Kittisak; Sritularak, Boonchoo; Wiwattanapatapee, Ruedeekorn

    2015-07-01

    The aim of this study was to develop and assess nanostructured lipid carriers (NLC) compared to solid lipid nanoparticles (SLN) for improving the oral bioavailability of oxyresveratrol (OXY). The OXY formulated as SLN (OXY-SLN) and NLC (OXY-NLC) were prepared by a high shear homogenization technique. The optimized OXY-NLC (NLC3) produced smaller nanoparticle sizes (96±0.9nm) than that of the OXY-SLN (108±0.3nm) with a homogeneous size distribution and a high zeta potential. The spherical NLC had a significantly higher efficiency for OXY entrapment (89±0.1%) and a better stability than the SLN after storage for 12 months at 4±2°C according to parameters such as smaller particles, greater zeta potential and a higher loading capacity (pSLN. The accumulated drug in an amorphous state in the NLC was also confirmed by powder X-ray diffraction (PXRD). The in vitro release profiles of the OXY-NLC showed a more sustained release compared to the SLN and unformulated OXY. The in vivo pharmacokinetic profiles implied enterohepatic recycling of OXY in the Wistar rat. Meanwhile, the oral absorption pattern of OXY was modified by both types of lipid nanoparticles. The SLN and NLC increased the relative bioavailability of OXY to 125% and 177%, respectively, compared with unformulated OXY. These findings indicated that NLC could be used as a potential carrier to improve the oral bioavailability of OXY.

  5. Crystal structure of dimethyl 2-((2Z,5Z)-5-(2-meth-oxy-2-oxo-ethyl-idene)-2-{(E)-[2-methyl-5-(prop-1-en-2-yl)cyclo-hex-2-enyl-idene]hydrazinyl-idene}-4-oxo-thia-zolidin-3-yl)fumarate.

    Science.gov (United States)

    N'ait Ousidi, Abdellah; Ait Itto, My Youssef; Auhmani, Aziz; Riahi, Abdelkhalek; Auhmani, Abdelwahed; Daran, Jean-Claude

    2017-02-01

    The crystal structure and the conformation of the title compound, C22H27N3O7S, were determined from the synthetic pathway and by X-ray analysis. This compound is a new 4-thia-zolidinone derivative prepared and isolated as pure product from thio-semicarbazone carvone. The mol-ecule is built up from an oxo-thia-zolidine ring tetra-substituted by a meth-oxy-oxo-ethyl-idene, a maleate, an oxygen and a cyclo-hexyl-idene-hydrazone. The cyclo-hexyl-idene ring is statistically disordered over two positions, resulting in an inversion of configuration for the substituted carbon.

  6. Rat traps: filling the toolbox for manipulating the rat genome

    OpenAIRE

    van Boxtel, Ruben; Cuppen, Edwin

    2010-01-01

    The laboratory rat is rapidly gaining momentum as a mammalian genetic model organism. Although traditional forward genetic approaches are well established, recent technological developments have enabled efficient gene targeting and mutant generation. Here we outline the current status, possibilities and application of these techniques in the rat.

  7. Tubuloglomerular feedback in Dahl rats

    DEFF Research Database (Denmark)

    Karlsen, F M; Leyssac, P P; Holstein-Rathlou, N H

    1998-01-01

    in both Dahl-S and salt-resistant Dahl rats on high- and low-salt diets. TGF was investigated in the closed-loop mode with a videometric technique, in which the response in late proximal flow rate to perturbations in Henle flow rate was measured. All Dahl rats showed a similar compensatory response...

  8. Do rats have orgasms?

    Science.gov (United States)

    Pfaus, James G.; Scardochio, Tina; Parada, Mayte; Gerson, Christine; Quintana, Gonzalo R.; Coria-Avila, Genaro A.

    2016-01-01

    Background Although humans experience orgasms with a degree of statistical regularity, they remain among the most enigmatic of sexual responses; difficult to define and even more difficult to study empirically. The question of whether animals experience orgasms is hampered by similar lack of definition and the additional necessity of making inferences from behavioral responses. Method Here we define three behavioral criteria, based on dimensions of the subjective experience of human orgasms described by Mah and Binik, to infer orgasm-like responses (OLRs) in other species: 1) physiological criteria that include pelvic floor and anal muscle contractions that stimulate seminal emission and/or ejaculation in the male, or that stimulate uterine and cervical contractions in the female; 2) short-term behavioral changes that reflect immediate awareness of a pleasurable hedonic reward state during copulation; and 3) long-term behavioral changes that depend on the reward state induced by the OLR, including sexual satiety, the strengthening of patterns of sexual arousal and desire in subsequent copulations, and the generation of conditioned place and partner preferences for contextual and partner-related cues associated with the reward state. We then examine whether physiological and behavioral data from observations of male and female rats during copulation, and in sexually-conditioned place- and partner-preference paradigms, are consistent with these criteria. Results Both male and female rats display behavioral patterns consistent with OLRs. Conclusions The ability to infer OLRs in rats offers new possibilities to study the phenomenon in neurobiological and molecular detail, and to provide both comparative and translational perspectives that would be useful for both basic and clinical research. PMID:27799081

  9. Do rats have orgasms?

    Directory of Open Access Journals (Sweden)

    James G. Pfaus

    2016-10-01

    Full Text Available Background: Although humans experience orgasms with a degree of statistical regularity, they remain among the most enigmatic of sexual responses; difficult to define and even more difficult to study empirically. The question of whether animals experience orgasms is hampered by similar lack of definition and the additional necessity of making inferences from behavioral responses. Method: Here we define three behavioral criteria, based on dimensions of the subjective experience of human orgasms described by Mah and Binik, to infer orgasm-like responses (OLRs in other species: 1 physiological criteria that include pelvic floor and anal muscle contractions that stimulate seminal emission and/or ejaculation in the male, or that stimulate uterine and cervical contractions in the female; 2 short-term behavioral changes that reflect immediate awareness of a pleasurable hedonic reward state during copulation; and 3 long-term behavioral changes that depend on the reward state induced by the OLR, including sexual satiety, the strengthening of patterns of sexual arousal and desire in subsequent copulations, and the generation of conditioned place and partner preferences for contextual and partner-related cues associated with the reward state. We then examine whether physiological and behavioral data from observations of male and female rats during copulation, and in sexually-conditioned place- and partner-preference paradigms, are consistent with these criteria. Results: Both male and female rats display behavioral patterns consistent with OLRs. Conclusions: The ability to infer OLRs in rats offers new possibilities to study the phenomenon in neurobiological and molecular detail, and to provide both comparative and translational perspectives that would be useful for both basic and clinical research.

  10. Binding of benzo(a)pyrene to DNA by cytochrome P-450 catalyzed one-electron oxidation in rat liver microsomes and nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Cavalieri, E.L.; Rogan, E.G.; Devanesan, P.D.; Cremonesi, P. (Univ. of Nebraska Medical Center, Omaha (USA)); Cerny, R.L.; Gross, M.L. (Univ. of Nebraska, Lincoln (USA)); Bodell, W.J. (Univ. of California, San Francisco (USA))

    1990-05-22

    To investigate whether cytochrome P-450 catalyzes the covalent binding of substrates to DNA by one-electron oxidation, the ability of both uninduced and 3-methylcholanthrene (MC) induced rat liver microsomes and nuclei to catalyze covalent binding of benzo(a)pyrene (BP) to DNA and formation of the labile adduct 7-(benzo(a)pyren-6-yl)guanine (BP-N7Gua) was investigated. In the various systems studied, 1-9 times more BP-N7Gua adduct was isolated than the total amount of stable BP adducts in the DNA. The specific cytochrome P-450 inhibitor 2-((4,6-dichloro-o-biphenyl)oxy)ethylamine hydrobromide (DPEA) reduced or eliminated BP metabolism, binding of BP to DNA, and formation of BP-N7Gua by cytochrome P-450 in both microsomes and nuclei. The effects of the antioxidants cysteine, glutathione, and p-methoxythiophenol were also investigated. This study represents the first demonstration of cytochrome P-450 mediating covalent binding of substrates to DNA via one-electron oxidation and suggests that this enzyme can catalyze peroxidase-type electron-transfer reactions.

  11. Rat myocardial protein degradation.

    Science.gov (United States)

    Steer, J H; Hopkins, B E

    1981-07-01

    1. Myocardial protein degradation rates were determined by following tyrosine release from rat isolated left hemi-atria in vitro. 2. After two 20 min preincubations the rate of tyrosine release from hemi-atria was constant for 4 h. 3. Skeletal muscle protein degradation was determined by following tyrosine release from rat isolated hemi-diaphragm (Fulks, Li & Goldberg, 1975). 4. Insulin (10(-7) M) inhibited tyrosine release from hemi-atria and hemi-diaphragm to a similar extent. A 48 h fast increased tyrosine release rate from hemi-diaphragm and decreased tyrosine release rate from hemi-atria. Hemi-diaphragm tyrosine release was inhibited by 15 mmol/l D-glucose but a variety of concentrations of D-glucose (0, 5, 15 mmol/l) had no effect on tyrosine release from hemi-atria. Five times the normal plasma levels of the branched-chain amino acids leucine, isoleucine and valine had no effect on tyrosine release from either hemi-atria or hemi-diaphragm.

  12. The Rat Race

    CERN Multimedia

    Stephen Haywood

    Dear Muriel, Being an animal, you are probably more familiar with rats than most of us. Yet it seems to me that our Community (not just ATLAS) is stuck in a huge "rat race". I am somewhat mystified as to how we have got ourselves into this and I wonder whether you or your readers could explain this - I give my own observations below. In HEP and ATLAS specifically, we are all working long hours and we are all becoming exhausted. There are people at Point 1 who are working day and night, every day of the week; there are people writing software who send emails round the clock, including weekends. It is one thing to have bursts of activity which require us to put in some longer hours, but in ATLAS, the bursts last months or years. I have been on ATLAS 14 years and it has felt like one endless rush. Why do we do this? We are all highly motivated, we love our work and want to succeed individually and collectively. We are parts of various teams, and we do not want to let the side down. We worked hard at school an...

  13. Male rat sexual behavior.

    Science.gov (United States)

    Agmo, A

    1997-05-01

    The male rat's sexual behavior constitutes a highly ordered sequence of motor acts involving both striate and smooth muscles. It is spontaneously displayed by most adult made rats in the presence of a sexually receptive female. Although the behavior is important for the survival of the species it is not necessary for survival of the individual. In that way it is different from other spontaneous behaviors such as eating, drinking, avoidance of pain, respiration or thermoregulation. Among other things, this means that it is difficult to talk about sexual deprivation or need. Nevertheless, studies of male sex behavior distinguish sexual motivation (the ease by which behavior is activated, "libido") from the execution of copulatory acts (performance, "potency") (Meisel, R.L. and Sachs, B.D., The physiology of male sexual behavior. In: E. Knobil and J.D. Neill (Eds.), The Physiology of Reproduction, 2nd Edn., Vol. 2, Raven Press, New York, 1994, pp. 3-105 [13]). The hormonal control of male sexual behavior has been extensively studied. It is clear that steroid hormones, androgens and estrogens, act within the central nervous system, modifying neuronal excitability. The exact mechanism by which these hormones activate sex behavior remains largely unknown. However, there exists a considerable amount of knowledge concerning the brain structures important for sexual motivation and for the execution of sex behavior. The modulatory role of some non-steroid hormones is partly known, as well as the consequences of manipulations of several neurotransmitter systems.

  14. Numerical analysis of flow behavior in tuyere and raceway of oxygen blast furnace with new type of oxy-coal burner%氧气高炉新型氧煤燃烧器设计参数对风口区流场影响数值模拟

    Institute of Scientific and Technical Information of China (English)

    张超; 张建良; 孙辉; 刘征建

    2016-01-01

    氧气高炉通过向风口回旋区喷吹煤粉以及脱除CO2的循环高炉煤气,可有效降低CO2排放。运用CFD商业软件,建立风口回旋区三维模型,针对氧气高炉所设计的新型燃烧器中氧煤枪数量及其与直吹管所呈角度和空间物理位置对风口回旋区流场的影响进行数值模拟。研究结果表明:采用单支氧煤枪操作,当其位于直吹管上部时,煤气流速度随喷吹角度由7°~15°变化时逐渐减小,且夹角为9°较为适宜,当其位于下部时,随着夹角越大,对风口回旋区深度增加越有利;采用双氧煤枪操作,当其在直吹管上下、左右分布时,夹角分别为11°和13°较合理;当单支氧煤枪位于直吹管上方且夹角为9°、距离d为75 mm时能较好地促进风口回旋区深度增加并保持足够的鼓风动能。%Oxygen blast furnace can effectively reduce CO2emissions by two means, pulverized coal injection and recycling of CO2-removed blast furnace gas. To study the velocity fieldamongthe tuyere and raceway region, a three-dimensional modelwasbuildupusing the commercial CFD software. The factors these numerical simulations mainly focus on the number of oxygen-coal lances, the angle and distance between the blowpipe and oxy-coal lances. Numerical results show that increasing angle between the blowpipe and oxy-coal lance from 7° to 15° results in lower velocity when the oxy-coal lanceisset above the blowpipe,the appropriate angle is 9°. When the lance is located below the blowpipe, the bigger the angle is, the deeper the raceway will be.Inaddition, when theoxy-coal burner has two lances, the lances are set at two sides of the blowpipe, i.e. vertical and horizontal distribution around the blowpipe, and the reasonable angles are 11° and 13°.Besides,the suitable distance between the blowpipe and oxy-coal lance is 75mm when the oxy-coal lanceisset above the blowpipe.

  15. Rat traps: filling the toolbox for manipulating the rat genome

    NARCIS (Netherlands)

    van Boxtel, R.; Cuppen, E.

    2010-01-01

    The laboratory rat is rapidly gaining momentum as a mammalian genetic model organism. Although traditional forward genetic approaches are well established, recent technological developments have enabled efficient gene targeting and mutant generation. Here we outline the current status, possibilities

  16. The thymus reconstituted nude rat

    DEFF Research Database (Denmark)

    Hougen, H P; Klausen, B

    1987-01-01

    The monoclonal antibodies OX6, OX19, W3/13, OX7, OX8, and W3/25 were used to gain information about the distribution of different lymphocyte subpopulations in peripheral lymphoid organs of neonatally isogeneic and allogeneic thymus reconstituted nude rats. Splenic mitogen responsiveness, xenogene...... cell response is far better following isografting. We, therefore, conclude that isogeneic thymus grafting is an easy method of reconstituting the nude rat immunologically....

  17. infarction in rats

    Directory of Open Access Journals (Sweden)

    Keyvan Yousefi

    2014-03-01

    Full Text Available Introduction: Nowadays, finding new therapeutic compounds from natural products for treatment and prevention of a variety of diseases including cardiovascular disorders is getting a great deal of attention. This approach would result in finding new drugs which are more effective and have fewer side effects than the conventional medicines. The present study was designed to investigate the anti-inflammatory effect of the methanolic extract of Marrubium vulgare, a popular traditional medicinal herb, on isoproterenol-induced myocardial infarction (MI in rat model. Methods: Male Wistar rats were assigned to 6 groups of control, sham, isoproterenol, and treatment with 10, 20, and 40 mg/kg/12h of the extract given orally concurrent with MI induction. A subcutaneous injection of isoproterenol (100 mg/kg/day for two consecutive days was used to induce MI. Then, histopathological changes and inflammatory markers were evaluated. Results: Isoproterenol injection increased inflammatory response, as shown by a significant increase in peripheral neutrophil count, myocardial myeloperoxidase (MPO activity and serum levels of creatinine kinase-MB (CK-MB and TNF-α (pM.vulgare extract serum CK-MB was subsided by 55.4%, 52.2% and 69%, respectively. Also treatment with the extract (40 mg/kg significantly reduced (p<0.001 MPO activity in MI group. The levels of TNF-α was also considerably declined in the serums of MI group (p<0.001. In addition, peripheral neutrophil count, was significantly lowered by all doses of the extract (p<0.001. Interstitial fibrosis significantly was attenuated in treated groups compared with control MI group.Conclusion:The results of study demonstrate that the M. vulgare extract has strong protective effects against isoproterenol-induced myocardial infarction and it seems possible that this protection is due to its anti-inflammatory effects.

  18. Zolpidem, a selective GABA(A) receptor alpha1 subunit agonist, induces comparable Fos expression in oxytocinergic neurons of the hypothalamic paraventricular and accessory but not supraoptic nuclei in the rat

    DEFF Research Database (Denmark)

    Kiss, Alexander; Søderman, Andreas; Bundzikova, Jana;

    2006-01-01

    Functional activation of oxytocinergic (OXY) cells in the hypothalamic paraventricular (PVN), supraoptic (SON), and accessory (ACC) nuclei was investigated in response to acute treatment with Zolpidem (a GABA(A) receptor agonist with selectivity for alpha(1) subunits) utilizing dual Fos/OXY immun...

  19. EXPERIMENTAL PARACOCCIDIOIDOMYCOSIS IN PREGNANT RATS

    Directory of Open Access Journals (Sweden)

    Eduardo Alexandre LOTH

    2015-12-01

    Full Text Available Paracoccidioidomycosis (PCM, caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb, is the most prevalent systemic mycosis in Latin America. There are few reports in the literature about the disease damages during pregnancy and the consequences to the fetuses and breeding. This study evaluated the implications of PCM during pregnancy on offspring and mothers in Wistar rats. Groups of rats were submitted to systemic Pb infection, by intraperitoneal infusion, and mated 30 days after the infection date. Immediately after birth, rats and neonates were sacrificed to obtain organs for standard histological examination, morphometric analysis, fungi recovery by plating (CFU and dosing of anti-Pb antibodies by ELISA. There were no stillbirths or miscarriages, however, the fetuses from infected pregnant rats had lower body and organ weight but the fertility rate was 100%. The largest number of CFU was recovered from the organ of pregnant rats, the pathological examination revealed more severe infection in the same group, further on the largest number of granulomas and fungal field. It can be concluded that the PCM was more severe in the group of pregnant rats, with implications to the weight of offspring.

  20. EXPERIMENTAL PARACOCCIDIOIDOMYCOSIS IN PREGNANT RATS.

    Science.gov (United States)

    Loth, Eduardo Alexandre; Cecatto, Vanessa; Biazim, Samia Khalil; Ferreira, José Henrique Fermino; Danielli, Caroline; Genske, Rodrigo Daniel; Gandra, Rinaldo Ferreira; Franco, Marcello Fabiano de

    2015-12-01

    Paracoccidioidomycosis (PCM), caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb), is the most prevalent systemic mycosis in Latin America. There are few reports in the literature about the disease damages during pregnancy and the consequences to the fetuses and breeding. This study evaluated the implications of PCM during pregnancy on offspring and mothers in Wistar rats. Groups of rats were submitted to systemic Pb infection, by intraperitoneal infusion, and mated 30 days after the infection date. Immediately after birth, rats and neonates were sacrificed to obtain organs for standard histological examination, morphometric analysis, fungi recovery by plating (CFU) and dosing of anti-Pb antibodies by ELISA. There were no stillbirths or miscarriages, however, the fetuses from infected pregnant rats had lower body and organ weight but the fertility rate was 100%. The largest number of CFU was recovered from the organ of pregnant rats, the pathological examination revealed more severe infection in the same group, further on the largest number of granulomas and fungal field. It can be concluded that the PCM was more severe in the group of pregnant rats, with implications to the weight of offspring.

  1. EXPERIMENTAL PARACOCCIDIOIDOMYCOSIS IN PREGNANT RATS

    Science.gov (United States)

    LOTH, Eduardo Alexandre; CECATTO, Vanessa; BIAZIM, Samia Khalil; FERREIRA, José Henrique Fermino; DANIELLI, Caroline; GENSKE, Rodrigo Daniel; GANDRA, Rinaldo Ferreira; de FRANCO, Marcello Fabiano

    2015-01-01

    Paracoccidioidomycosis (PCM), caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb), is the most prevalent systemic mycosis in Latin America. There are few reports in the literature about the disease damages during pregnancy and the consequences to the fetuses and breeding. This study evaluated the implications of PCM during pregnancy on offspring and mothers in Wistar rats. Groups of rats were submitted to systemic Pb infection, by intraperitoneal infusion, and mated 30 days after the infection date. Immediately after birth, rats and neonates were sacrificed to obtain organs for standard histological examination, morphometric analysis, fungi recovery by plating (CFU) and dosing of anti-Pb antibodies by ELISA. There were no stillbirths or miscarriages, however, the fetuses from infected pregnant rats had lower body and organ weight but the fertility rate was 100%. The largest number of CFU was recovered from the organ of pregnant rats, the pathological examination revealed more severe infection in the same group, further on the largest number of granulomas and fungal field. It can be concluded that the PCM was more severe in the group of pregnant rats, with implications to the weight of offspring. PMID:27049707

  2. Actions of Angeli's salt, a nitroxyl (HNO) donor, on ion transport across mucosa-submucosa preparations from rat distal colon.

    Science.gov (United States)

    Pouokam, Ervice; Bell, Anna; Diener, Martin

    2013-09-05

    The aim of this study was to investigate whether nitroxyl (HNO), a redox variant of the radical gasotransmitter nitric oxide (NO) with therapeutically promising properties, affects colonic ion transport. Changes in short-circuit current (Isc) induced by the HNO donor Angeli's salt were recorded in Ussing chambers. Cytosolic Ca(2+) concentration was measured with fura-2. The nitroxyl donor induced a concentration-dependent increase in Isc across rat distal colon which was due to a stimulation of chloride secretion. The secretion induced by Angeli's salt (5×10(-4)mol/l) was not altered by the NO scavenger 2-(4-carboxyphenyl)-4,5-dihydro-4,4,5,5-tetramethyl-1H-imidazolyl-1-oxy-3-oxide (carboxy-PTIO), but was abolished by the HNO scavenger l-cysteine. The response was not dependent on the activity of soluble guanylate cyclase or enteric neurons, but was inhibited by indomethacin. Experiments with apically permeabilized epithelia revealed the activation of basolateral K(+) channels and a stimulation of the current carried by the basolateral Na(+)-K(+)-pump by Angeli's salt. The secretion induced by Angeli's salt was reduced in the absence of extracellular Ca(2+). A prominent increase in the cytosolic Ca(2+) concentration was evoked by Angeli's salt predominantly in subepithelial cells within the submucosa, which had the same dependence on extracellular Ca(2+) as the Angeli's salt-induced Cl(-) secretion. Consequently, Angeli's salt induces a soluble guanylate cyclase-independent, Ca(2+)-dependent Cl(-) secretion via activation of the Na(+)-K(+)-ATPase and of basolateral K(+) channels. Cyclooxygenase metabolites produced within the submucosa seem to be involved in this response.

  3. Simultaneous recording of ATP-sensitive K+ current and intracellular Ca2+ in anoxic rat ventricular myocytes. Effects of glibenclamide.

    Science.gov (United States)

    Russ, U; Englert, H; Schölkens, B A; Gögelein, H

    1996-05-01

    We investigated the temporal relationship between the adenosine triphosphate-sensitive K current (KATP current), hypoxic shortening and Ca accumulation in cardiomyocytes exposed to anoxia or metabolic inhibition. Whole-cell, patch-clamp experiments were performed with nonstimulated isolated rat heart ventricular muscle cells loaded with the Ca-sensitive fluorescent dye 1-[2-(5-carboxyoxazol-2-yl)-6-aminobenzofuran-5-oxy]-2-(2'- amino-5'-methylphenoxy) ethane-N,N,N',N'-tetraacetic acid (fura-2) via the patch pipette. After approximately 8 min anoxia, the KATP current started to rise and reached a maximum of 21.3 +/- 3.7 nA (n = 5, recorded at 0 mV clamp potential) within 1-3 min. At that time hypoxic contracture also occurred. Resting cytoplasmic free calcium (Cai) did not change significantly before hypoxic shortening. After hypoxic contracture, the KATP current decreased and Cai started to rise, reaching about 1 micromol/l. The presence of glibenclamide (10 micromol/l) in the bath reduced the anoxia-induced KATP current by more than 50%, but did not significantly influence the time dependence of current, hypoxic shortening and Cai, or the magnitude of Cai. Metabolic inhibition with 1.5 mmol/l CN resulted in KATP current increase and hypoxic shortening, occurring somewhat earlier than under anoxia, but all other parameters were comparable. In non-patch-clamped cells loaded with fura-2 AM ester and field-stimulated with 1 Hz, 1 micronol/l glibenclamide had no significant effect on the magnitude of the Cai increase caused by exposure of the cells to 1.5 mmol/l CN-. After CN- wash-out in non-patch-clamped cells, Cai declined, oscillated and finally returned to control values. It can be concluded that glibenclamide inhibits anoxia-induced KATP currents only partially and has no significant effect on anoxia-induced rise in resting Cai.

  4. Comparison of the crystal structures of methyl 4-bromo-2-(meth-oxy-meth-oxy)benzoate and 4-bromo-3-(meth-oxy-meth-oxy)benzoic acid.

    Science.gov (United States)

    Suchetan, P A; Suneetha, V; Naveen, S; Lokanath, N K; Krishna Murthy, P

    2016-04-01

    The title compounds, C10H11BrO4, (I), and C9H9BrO4, (II), are derivatives of bromo-hy-droxy-benzoic acids. Compound (II) crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In both (I) and (II), the O-CH2-O-CH3 side chain is not in its fully extended conformation; the O-C-O-C torsion angle is 67.3 (3) ° in (I), and -65.8 (3) and -74.1 (3)° in mol-ecules A and B, respectively, in compound (II). In the crystal of (I), mol-ecules are linked by C-H⋯O hydrogen bonds, forming C(5) chains along [010]. The chains are linked by short Br⋯O contacts [3.047 (2) Å], forming sheets parallel to the bc plane. The sheets are linked via C-H⋯π inter-actions, forming a three-dimensional architecture. In the crystal of (II), mol-ecules A and B are linked to form R 2 (2)(8) dimers via two strong O-H⋯O hydrogen bonds. These dimers are linked into ⋯A-B⋯A-B⋯A-B⋯ [C 2 (2)(15)] chains along [011] by C-H⋯O hydrogen bonds. The chains are linked by slipped parallel π-π inter-actions [inter-centroid distances = 3.6787 (18) and 3.8431 (17) Å], leading to the formation of slabs parallel to the bc plane.

  5. DOPA, norepinephrine, and dopamine in rat tissues

    DEFF Research Database (Denmark)

    Eldrup, E; Richter, Erik; Christensen, N J

    1989-01-01

    We studied the effect of unilateral sympathectomy on rat quadriceps and gastrocnemius muscle concentrations of endogenous dihydroxyphenylalanine (DOPA), dopamine (DA), and norepinephrine (NE) and assessed the relationships between these catecholamines in several rat tissues. Catecholamines were...

  6. Continuous enteral feeding in uremic rats.

    Science.gov (United States)

    Maniar, S; Laouari, D; Motel, V; Kleinknecht, C

    1996-01-01

    Because of constant uremia-induced anorexia, food restriction of normal rats is generally used to study the consequences of uremia. The effects of a normal food supply in uremic rats has never been tested, since no author has succeeded in providing normal intakes. Uremic rats either fed ad lib (U rats, n = 12) or force-fed through a gastric catheter (UF rats, n = 10), and sham-operated rats (C rats, n = 10) were compared from days 7 to 21 after surgery. U rats had lower food intake (13.8 vs. 17 g/day), weight gain (5.16 vs. 6.23 g/day), length gain (4 vs. 5 mm/day), nitrogen balance (228 vs. 279 mg/day) and muscle fractional protein synthesis rate (9.5 vs. 10.6%) measured in vivo by 3H-phenylalanine injection (p feeding may provide a model for normal nutritional supply in uremia.

  7. 盐酸羟考酮控释片治疗老年癌痛体会%Treatment for cancerous pain in the elderly with Oxy-Codone hydrochloride controlled-release tablets.

    Institute of Scientific and Technical Information of China (English)

    刘彦芳; 刘端祺; 李红英; 张侠

    2010-01-01

    Objective To evaluate effectiveness and side effects, as well as its safety, of Oxy-Codone hydrochloride controlled-release tablets (Oxycontin) for the elderly patients with moderate to severe cancerous pain. Methods From March 2005 to February 2009,106 elderly patients ( aged more than 60 years) suffered from moderate to severe cancerous pain were treated with Oxycontin,at initial dose of 10 mg/12 h. For the patients using making them pain-free or pain relieved mostly. Every patient was treated for 4 weeks at least. Severity of pain,sleeping status, appetite, fatigue, mental status, daily life, scores of understanding and cooperation, and side effects were .observed.Results The minimal effective dose of Oxycontin was 10 mg/d for the elderly patients with cancerous pain. Twenty-three patients (21.7%) were treated with it at dose of ≥200 mg/d,30 patients (28. 2% )at dose of 100 - 180 mg/d,and 53 patients (50. 0% ) at dose of 10 -90 mg/d. Pain was relieved in 97. 16% of the patients after treatment, with common side effects of constipation, nausea, vomiting;and drug treatment was needed for 24. 53% (26/106) of the patients with more common constipation. Conclusions Oxycontin is effective,tolerable,less side-effects for the elderly patients with moderate to severe cancerous pain, and can improve their quality of life.%目的 观察盐酸羟考酮控释片(商品名:奥施康定),治疗老年恶性肿瘤患者中、重度疼痛的临床效果及不良反应,明确该药在治疗老年癌痛中的有效性及安全性.方法 2005年3月至2009年2月中、重度疼痛老年恶性肿瘤患者(年龄≥60岁)106例,给予盐酸羟考酮控释片镇痛治疗,初始剂量10 mg/12 h,正在用吗啡类镇痛药者,按照口服吗啡1/2剂量换算,根据疼痛情况调整剂量,直至患者无痛或基本无痛,每位患者至少治疗4周以上.同时进行疼痛强度、睡眠、食欲、疲乏、精神状态、日常生活、理解配合程度评

  8. False Context Fear Memory in Rats

    Science.gov (United States)

    Bae, Sarah; Holmes, Nathan M.; Westbrook, R. Frederick

    2015-01-01

    Four experiments used rats to study false context fear memories. In Experiment 1, rats were pre-exposed to a distinctive chamber (context A) or to a control environment (context C), shocked after a delay in a second chamber (context B) and tested either in B or A. Rats pre-exposed to A froze just as much as control rats in B but more than control…

  9. EFFECT OF ETHANOL ON HEPATOBILIARY TRANSPORT OF CATIONIC DRUGS - A STUDY IN THE ISOLATED-PERFUSED RAT-LIVER, RAT HEPATOCYTES AND RAT MITOCHONDRIA

    NARCIS (Netherlands)

    STEEN, H; MEIJER, DKF; Merema, M.T.

    1994-01-01

    The effect of ethanol on the hepatic uptake of various cationic drugs was studied in isolated perfused rat livers, isolated rat hepatocytes and isolated rat liver mitochondria. In isolated rat hepatocytes and in isolated perfused rat livers, the uptake of the model organic cation tri-n-butylmethylam

  10. The serotonin transporter knockout rat : A review

    NARCIS (Netherlands)

    Olivier, Jocelien; Cools, Alexander; Ellenbroek, Bart A.; Cuppen, E.; Homberg, Judith; Kalueff, Allan V.; LaPorte, Justin L.

    2010-01-01

    This chapter dicusses the most recent data on the serotonin transporter knock-out rat, a unique rat model that has been generated by target-selected N-ethyl-N-nitrosourea (ENU) driven mutagenesis. The knock-out rat is the result of a premature stopcodon in the serotonin transporter gene, and the abs

  11. Tuberculosis Detection by Giant African Pouched Rats

    Science.gov (United States)

    Poling, Alan; Weetjens, Bart; Cox, Christophe; Beyene, Negussie; Durgin, Amy; Mahoney, Amanda

    2011-01-01

    In recent years, operant discrimination training procedures have been used to teach giant African pouched rats to detect tuberculosis (TB) in human sputum samples. This article summarizes how the rats are trained and used operationally, as well as their performance in studies published to date. Available data suggest that pouched rats, which can…

  12. Structural analysis of (S)-1-((1H-benzo[d][1,2,3]triazol-1-yl)oxy)-3-(4-(2-methoxyphenyl)piperazin-1-yl)propan-2-ol and binding mechanism with α1A-adrenoceptor: TDDFT calculations, X-ray crystallography and molecular docking

    Science.gov (United States)

    Xu, Wei; Shao, Binhao; Xu, Xingjie; Jiang, Renwang; Yuan, Mu

    2016-02-01

    The title compound, (S)-1-((1H-benzo[d][1,2,3]triazol-1-yl)oxy)-3-(4-(2-methoxyphenyl)piperazi-n-1-yl)propan-2-ol (1), belongs to a class of arylpiperazine derivatives that exhibit good bioactivity against α1A-adrenoceptor. The current study describes conformational analysis of five energy-minimized conformers obtained at the B3LYP/6-31G(d) level of theory. The characteristically positive rotatory strengths at an excitation energy of 256 nm were achieved using time-dependent density functional theory (TDDFT) calculations. Molecular orbital studies clearly elucidated the origins of electronic transitions at 256 nm. The absolute configuration of (S)-1 was unambiguously determined by single crystal X-ray diffraction analysis. Molecular docking solved the binding mode of 1-α1A-adrenoceptor complex. This work can serve as a basis for better drug design of highly selective antagonists with chirality.

  13. Crystal structure and Hirshfeld surface analysis of 1-carb­oxy-2-(3,4-di­hydroxy­phen­yl)ethan-1-aminium bromide 2-ammonio-3-(3,4-di­hydroxy­phen­yl)propano­ate

    OpenAIRE

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-01-01

    In the title mol­ecular salt, C9H12NO4 +·Br−·C9H11NO4, one of the dopa mol­ecules is in the cationic form in which the α-amino group is protonated and the α-carb­oxy­lic acid group is uncharged, while the second dopa mol­ecule is in the zwitterion form. The Br− anion occupies a special position and is located on a twofold rotation axis. The two dopa mol­ecules are inter­connected by short O—H⋯O hydrogen bonds. In the crystal, the various units are linked by O—H⋯O, N—H⋯Br and N—H⋯O hydrogen bo...

  14. (1S,2R,7R,8S,10R)-9,9-Di-bromo-2,6,6,10-tetra-methyl-1α,2α-ep-oxy-tri-cyclo-[5.5.0.0(8,10)]dodeca-ne.

    Science.gov (United States)

    Benharref, Ahmed; El Karroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2013-01-01

    The title compound, C16H24Br2O, was synthesized from the reaction of β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzo-cyclo-heptene), which was isolated from Atlas cedar (Cedrus atlantica) essential oil, after reaction with di-bromo-carbene. The asymmetric unit contains two independent mol-ecules with similar conformations. Each mol-ecule is built up from fused six-and seven-membered rings and two three-membered rings. In both mol-ecules, the six-membered ring has an envelope conformation with the flap provided by the C atom of the ep-oxy ring, whereas the seven-membered ring displays a chair conformation. The crystal packing is governed only by van der Waals inter-actions. The absolute configuration was established from anomalous dispersion effects.

  15. Synthesis of 18 F Labeled Precursor of 3-{[ 3 ,5- Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)-4-oxo-4H-chromen-7-yl] oxy}-propyl-4-methylbenzenesulfonate%18 F标记前体3′-甲氧基-7-对甲苯磺酰 氧丙氧基槲皮素的合成

    Institute of Scientific and Technical Information of China (English)

    韩巧; 张敏杰; 马鲲原; 曾湘彪; 郑易林; 曹培; 苏甫; 何菱

    2016-01-01

    以槲皮素为起始原料,经酰化、醚化、苄醚化、脱苄、甲基化、水解6步反应合成了18 F标记前体3′-甲氧基-7-对甲苯磺酰氧丙氧基槲皮素,其结构经1 H NMR,13 C NMR和HR-MS(ESI)确证.%The 18 F labeled precursor of 3-{[3,5-dihydroxy-2-(3-hydroxy-4-methoxyphenyl)-4-oxo-4H-chromen-7-yl] oxy}-propyl-4-methylbenzenesulfonate was synthesized by a six-step reaction of acyla-tion, esterification, etherification, debenzylation, methylation and hydrolyzation. The structure was confirmed by 1 H NMR, 13 C NMR and HR-MS( ESI) .

  16. Crystal structure and Hirshfeld surface analysis of 1-carb­oxy-2-(3,4-di­hydroxy­phen­yl)ethan-1-aminium bromide 2-ammonio-3-(3,4-di­hydroxy­phen­yl)propano­ate

    Science.gov (United States)

    Kathiravan, Perumal; Balakrishnan, Thangavelu; Venkatesan, Perumal; Ramamurthi, Kandasamy; Percino, María Judith; Thamotharan, Subbiah

    2016-01-01

    In the title mol­ecular salt, C9H12NO4 +·Br−·C9H11NO4, one of the dopa mol­ecules is in the cationic form in which the α-amino group is protonated and the α-carb­oxy­lic acid group is uncharged, while the second dopa mol­ecule is in the zwitterion form. The Br− anion occupies a special position and is located on a twofold rotation axis. The two dopa mol­ecules are inter­connected by short O—H⋯O hydrogen bonds. In the crystal, the various units are linked by O—H⋯O, N—H⋯Br and N—H⋯O hydrogen bonds, forming a three-dimensional framework. The title compound was refined as an inversion twin with an absolute structure parameter of 0.023 (8). PMID:27840704

  17. Crystal structure of poly[[μ-1,1′-(butane-1,4-diylbis(1H-benzimidazole-κ2N3:N3′]{μ-4,4′-[1,4-phenylenebis(oxy]dibenzoato-κ4O,O′:O′′,O′′′}cobalt(II

    Directory of Open Access Journals (Sweden)

    Chen Xie

    2015-06-01

    Full Text Available In the title compound, [Co(C20H12O6(C18H18N4]n, the CoII atom, located on a twofold rotation axis, is hexacoordinated to four O from two bis-bidentate 4,4′-[phenylenebis(oxy]dibenzoate (L ligands and two N atoms from two 1,1′-(butane-1,4-diylbis(1H-benzimidazole (bbbm ligands, forming a distorted octahedral cis-N2O4 coordination environment. Polymeric zigzag chains along [102] are built up by the bridging L ligands. These chains are additionally connected by the bbbm ligands to produce a two-dimensional coordination polymer parallel too (010.

  18. Spectroscopic studies and structure of 3-methoxy-2 -[(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Oezay, H.; Yildiz, M., E-mail: myildiz@comu.edu.tr [Canakkale Onsekiz Mart University, Department of Chemistry, Faculty of Science and Arts (Turkey); Uenver, H.; Durlu, T. N. [Ankara University, Department of Physics, Faculty of Science (Turkey)

    2013-01-15

    The compound called 3-methoxy-2- [(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with hexachlorocyclotriphosphazene. It has been characterized by elemental analysis, MS, IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and UV-visible spectroscopic techniques. The structure of the title compound has been determind by X-ray analysis. Crystals are orthorhombic, space group P2{sub 1}2{sub 1}2{sub 1}, Z = 4, a = 7.705(1), b = 12.624(1), c = 17.825(2) A, R{sub 1} = 0.0390 and wR{sub 2} = 0.1074 [I > 2{sigma}(I)], respectively.

  19. Overview of ultraviolet and infrared spectroscopic properties of Yb{sup 3+} doped borate and oxy-borates compounds; De l'ultraviolet a l'infrarouge: caracterisation spectroscopique de materiaux type borate et oxyborate dopes a l'ytterbium trivalent

    Energy Technology Data Exchange (ETDEWEB)

    Sablayrolles, J

    2006-12-15

    The trivalent ytterbium ion can give rise to two emissions with different spectroscopic properties: the first one, with a short lifetime, in the ultraviolet (charge transfer emission) is used in detectors such as scintillators, and the other one, with a long lifetime, in the infrared (4f-4f emission) for laser applications. The strong link between material structure and properties is illustrated through ytterbium luminescence study, in the ultraviolet and infrared, inserted in the borate Li{sub 6}Y(BO{sub 3}){sub 3} and two oxy-borates: LiY{sub 6}O{sub 5}(BO{sub 3}){sub 3} and Y{sub 17,33}B{sub 8}O{sub 38}. For the first time an ytterbium charge transfer emission in oxy-borates has been observed. The calculation of the single configurational coordinate diagram, as well as the thermal quenching, has been conducted under a fundamental approach on the ytterbium - oxygen bond. The study of the ytterbium infrared spectroscopy in these compounds has been realised and an energy level attribution is proposed in the particular case of the borate Li{sub 6}Y(BO{sub 3}){sub 3}: Yb{sup 3+}. An original approach is introduced with the study of the charge transfer states for the three compounds by looking at the infrared emission. The first laser performances in three operating modes (continuous wave, Q-switch and mode locking) of a Li{sub 6}Y(BO{sub 3}){sub 3}: Yb{sup 3+} crystal are reported. (author)

  20. Magnetocardiogram Measurement of Laboratory Rat

    Energy Technology Data Exchange (ETDEWEB)

    Kim, I. S.; Ahn, San; Kwon, H. C. [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Song, J. H. [Chungnam National University, Daejeon (Korea, Republic of)

    2010-04-15

    We have developed a high-Tc SQUID magnetocardiogram (MCG) system for small laboratory animals. White noise of the measurement system was about 30 fT/ Hz{sup 1/2}when measured in a magnetically shielded room. We optimized the measurement position to obtain clear MCG wave from rat's small heart by using grid measurements. With the optimization, the MCG signal was successfully detected with the peak amplitude of about 30 pT. We could observe well defined P-, QRS-, and T-waves from the rat MCG. The results suggest that the developed system has a strong potential to monitor the progress of the heart disease model by using a laboratory rat.

  1. Metabolism of Deltamethrin in Rats

    Institute of Scientific and Technical Information of China (English)

    S.EL-MAGHRABY

    2007-01-01

    Objective To study the membolism of 14C-deltamethrin in rats. Methods Rats were dosed orally and i.p.with a single dose of 14C-deltamethrin(0.64 mg/Kg)body weight.The required dose was applied daily for 3 days.At the end of the experiment,selected organs,such as liver,kidney,fat,intestine,and blood were excised for radioassay of 14C-content.Results Deltamethrin was almost eliminated from the body within 1-3 days.The main portion of 14C-residues Was extracted from urine(38%,32%)and feces(20%,24%)with a little amount remained in various organs. Conclusion The elimination and distribution of 14C-radioactivity in rats treated orally and intraperitoneally signify th6at deltamethrin is bioavailable in urine and feces.

  2. Teratology studies in the rat.

    Science.gov (United States)

    Leroy, Mariline; Allais, Linda

    2013-01-01

    The rat is the rodent species of choice for the regulatory safety testing of xenobiotics, such as medicinal products, food additives, and other chemicals. Many decades of experience and extensive data have accumulated for both general and developmental toxicology investigations in this species. The high fertility and large litter size of the rat are advantages for teratogenicity testing. The study designs are well defined in the regulatory guidelines and are relatively standardized between testing laboratories across the world. Teratology studies address maternal- and embryo-toxicity following exposure during the period of organogenesis. This chapter describes the design and conduct of a teratology study in the rat in compliance with the regulatory guidelines. The procedures for the handling and housing of the pregnant animals, the caesarean examinations and the sampling of fetuses for morphological examinations are described. The utility and design of preliminary studies and the inclusion of satellite animals in the main study for toxicokinetic sampling are discussed.

  3. State Space Methods in RATS

    Directory of Open Access Journals (Sweden)

    Thomas Doan

    2011-05-01

    Full Text Available This paper uses several examples to show how the econometrics program RATS can be used to analyze state space models. It demonstrates Kalman filtering and smoothing, estimation of hyperparameters, unconditional and conditional simulation. It also provides a more complicated example where a dynamic simultaneous equations model is transformed into a proper state space representation and its unknown parameters are estimated.

  4. Trigeminovascular stimulation in conscious rats

    NARCIS (Netherlands)

    Kemper, RHA; Meijler, WJ; TerHorst, GJ

    1997-01-01

    INTRACISTERNAL infusion of capsaicin was used to induce intracranial trigeminovascular stimulation in conscious rats. Both behaviour and trigeminal nucleus caudalis c-fos expression were examined. Exploratory behaviour was dose-dependently reduced and different types of behaviours were induced with

  5. Immortalized Rat Astrocyte Strain Genetically Modified by Rat Preprogalanin Gene

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    To construct an immortalized rat astrocyte strain genetically modified by rat preprogalanin gene (IAST/GAL) and detect its galanin (GAL) expression and secretion, a cDNA fragment of rat GAL in plasmid of pBS KS(+)-GAL was inserted into eukaryotic expression vector pcDNA3.1(+) by DNA recombinant technology, then the restriction enzyme digestion and DNA sequencing were carried out to evaluate the recombinant. The pcDNA3.1 (+)-GAL and pcDNA3.1 (+) construct were transfected into immortalized rat astrocyte strain (IAST) by lipofectamine and the population of cells which stably integrated the construct was selected with 600 μg/mL G418. Individual clones were screened and expanded into clonal cell strains. Detection of Neo gene was used to validate the success of the transfection. Immunocytochemical staining, RT-PCR and radioimmunoassay were used to detect the expression and secretion level of GAL. The recombinant had been successfully constructed by restriction enzyme digestion and DNA sequencing. Detection of Neo gene showed that the pcDNA3.1 (+)-GAL and pcDNA3.1 (+) have been successfully transfected into IAST. After selection by using G418, IAST/GAL and IAST/Neo cell strains were obtained.IAST/GAL, IAST/Neo and IAST were immunostained positively for GAL, but the GAL average optical density of IAST/GAL was significantly higher than that of IAST/Neo and IAST (P<0.01). The level of GAL mRNA expression and the supernatant concentration of GAL in cultured IAST/GAL were significantly higher than those of IAST and IAST/Neo (P<0.01), but no significant differences were found between the IAST and IAST/Neo (P>0.05). It was concluded that IAST/GAL strain was constructed successfully and it might provide a basis for the further study of pain therapy.

  6. Genome Editing in Rats Using TALE Nucleases.

    Science.gov (United States)

    Tesson, Laurent; Remy, Séverine; Ménoret, Séverine; Usal, Claire; Thinard, Reynald; Savignard, Chloé; De Cian, Anne; Giovannangeli, Carine; Concordet, Jean-Paul; Anegon, Ignacio

    2016-01-01

    The rat is an important animal model to understand gene function and model human diseases. Since recent years, the development of gene-specific nucleases has become important for generating new rat models of human diseases, to analyze the role of genes and to generate human antibodies. Transcription activator-like (TALE) nucleases efficiently create gene-specific knockout rats and lead to the possibility of gene targeting by homology-directed recombination (HDR) and generating knock-in rats. We describe a detailed protocol for generating knockout and knock-in rats via microinjection of TALE nucleases into fertilized eggs. This technology is an efficient, cost- and time-effective method for creating new rat models.

  7. Hemodynamic and Light-Scattering Changes of Rat Spinal Cord and Primary Somatosensory Cortex in Response to Innocuous and Noxious Stimuli

    Directory of Open Access Journals (Sweden)

    Ji-Wei He

    2015-09-01

    Full Text Available Neuroimaging technologies with an exceptional spatial resolution and noninvasiveness have become a powerful tool for assessing neural activity in both animals and humans. However, the effectiveness of neuroimaging for pain remains unclear partly because the neurovascular coupling during pain processing is not completely characterized. Our current work aims to unravel patterns of neurovascular parameters in pain processing. A novel fiber-optic method was used to acquire absolute values of regional oxy- (HbO and deoxy-hemoglobin concentrations, oxygen saturation rates (SO2, and the light-scattering coefficients from the spinal cord and primary somatosensory cortex (SI in 10 rats. Brief mechanical and electrical stimuli (ranging from innocuous to noxious intensities as well as a long-lasting noxious stimulus (formalin injection were applied to the hindlimb under pentobarbital anesthesia. Interhemispheric comparisons in the spinal cord and SI were used to confirm functional activation during sensory processing. We found that all neurovascular parameters showed stimulation-induced changes; however, patterns of changes varied with regions and stimuli. Particularly, transient increases in HbO and SO2 were more reliably attributed to brief stimuli, whereas a sustained decrease in SO2 was more reliably attributed to formalin. Only the ipsilateral SI showed delayed responses to brief stimuli. In conclusion, innocuous and noxious stimuli induced significant neurovascular responses at critical centers (e.g., the spinal cord and SI along the somatosensory pathway; however, there was no single response pattern (as measured by amplitude, duration, lateralization, decrease or increase that was able to consistently differentiate noxious stimuli. Our results strongly suggested that the neurovascular response patterns differ between brief and long-lasting noxious stimuli, and can also differ between the spinal cord and SI. Therefore, a use of multiple

  8. Analysis of Heme oxygenase isomers in rat

    Institute of Scientific and Technical Information of China (English)

    Yun-ZhuLi; Wen-JunCui; Xue-HongZhang; Qing-XiangShen; JianWang; She

    2002-01-01

    AIM:To purify and identify heme oxygenase(HO) isomers which exist in rat liver,spleen and brain treated with hematin and phenylhydrazine and in untrated rat liver and to investigate the characteristics of HO isomers,to isolate and confirm the rat HO-1 cDNA that actually encodes HO-1 by expressing cDNA in monkey Kidney cells(COS-1 cells),to prepare the rat heme oxygenase-1(HO-1)mutant and to detect inhibition of HO-1 mutated enzyme.

  9. Rats Train As Landmine Detectors

    Institute of Scientific and Technical Information of China (English)

    单献心

    2000-01-01

    鼠,也有“改邪归正”之日!比利时的研究人员正在训练老鼠当地雷侦察员。收效甚奇:Trained rats may be the best and cheapest form of landmine(地雷)detector. 不过,老鼠心甘情愿地去发现地雷,并非被灌输了什么“为民除害”的思想,而是为了食物,为了生存: Once the minefield has been mapped,the rats sniff out a landmine and sitbeside it waiting to be rewarded with food.

  10. Pathophysiology of the Belgrade Rat

    Directory of Open Access Journals (Sweden)

    Tania eVeuthey

    2014-04-01

    Full Text Available The Belgrade rat is an animal model of Divalent Metal Transporter-1 (DMT1 deficiency. This strain originates from an X-irradiation experiment first reported in 1966. Since then, the Belgrade rat’s pathophysiology has helped to reveal the importance of iron balance and the role of DMT1. This review discusses our current understanding of iron transport homeostasis and summarizes molecular details of DMT1 function. We describe how studies of the Belgrade rat have revealed key roles for DMT1 in iron distribution to red blood cells as well as duodenal iron absorption. The Belgrade rat’s pathology has extended our knowledge of hepatic iron handling, pulmonary and olfactory iron transport as well as brain iron uptake and renal iron handling. For example, relationships between iron and manganese metabolism have been discerned since both are essential metals transported by DMT1. Pathophysiologic features of the Belgrade rat provide us with a unique and interesting animal model to understand iron homeostasis.

  11. Developmental toxicity of isomalt in rats.

    Science.gov (United States)

    Waalkens-Berendsen, D H; Koëter, H B; Schlüter, G; Renhof, M

    1989-10-01

    The sugar replacer isomalt, a 1:1 mixture of the disaccharides glucopyranosylsorbitol and glucopyranosylmannitol, was incorporated in the diet of rats. Female Bay FB:30 rats were adapted to isomalt by feeding them a diet containing a gradually increasing amount of isomalt for several days, prior to mating. Subsequently, they were mated. Isomalt was fed continuously in concentrations of 2.5, 5 and 10% up to day 20 of pregnancy. In addition, one group of female Wistar rats was mated and fed 10% isomalt incorporated in the diet from day 0 up to day 20 of pregnancy, without previous adaptation to isomalt. Finally, one group of untreated female Wistar rats served as controls. Half of the number of females in each group was selected for caesarian section on day 20 of pregnancy. The other half was allowed to litter and rear their pups for 2 weeks (Wistar rats) or 3 weeks (Bay FB:30 rats). In the females of the Bay FB:30 rats, a decreased body-weight gain and food consumption were observed in the 5 and 10% isomalt group. Minor retardation in the development of the foetuses was observed in the 10% isomalt group only with the Bay FB:30 rats and was therefore considered to be related to maternal toxicity. In addition, a dose-related increase in the incidence of wavy ribs occurred in foetuses of the Bay FB:30 rats. However, none of the observed effects were persistent in neonates. Isomalt appeared to have slight toxic effects in the dams of the Bay FB:30 strain but no toxicity in the offspring. In Wistar rats no toxicity and no effects on maternal performance or on embryonic, foetal or neonatal development were seen. Isomalt, when fed at dietary levels up to 10%, did not induce structural or functional teratogenic effects in rats of either the Wistar or the Bay FB:30 strain.

  12. Modulation of rat behaviour by using a rat-like robot.

    Science.gov (United States)

    Shi, Qing; Ishii, Hiroyuki; Kinoshita, Shinichi; Takanishi, Atsuo; Okabayashi, Satoshi; Iida, Naritoshi; Kimura, Hiroshi; Shibata, Shigenobu

    2013-12-01

    In this paper, we study the response of a rat to a rat-like robot capable of generating different types of behaviour (stressful, friendly, neutral). Experiments are conducted in an open-field where a rat-like robot called WR-4 is put together with live rats. The activity level of each rat subject is evaluated by scoring its locomotor activity and frequencies of performing rearing (rising up on its hind limbs) and body grooming (body cuddling and head curling) actions, whereas the degree of preference of that is indicated by the robot-rat distance and the frequency of contacting WR-4. The moving speed and behaviour of WR-4 are controlled in real-time based on the feedback from rat motion. The activity level and degree of preference of rats for each experimental condition are analysed and compared to understand the influence of robot behaviour. The results of this study show that the activity level and degree of preference of the rat decrease when exposed to a stressful robot, and increase when the robot exhibit friendly behaviour, suggesting that a rat-like robot can modulate rat behaviour in a controllable, predictable way.

  13. A Novel Rat Model of Type 2 Diabetes: The Zucker Fatty Diabetes Mellitus ZFDM Rat

    Directory of Open Access Journals (Sweden)

    Norihide Yokoi

    2013-01-01

    Full Text Available The Zucker fatty (ZF rat harboring a missense mutation (fatty, fa in the leptin receptor gene (Lepr develops obesity without diabetes; Zucker diabetic fatty (ZDF rats derived from the ZF strain exhibit obesity with diabetes and are widely used for research on type 2 diabetes (T2D. Here we establish a novel diabetic strain derived from normoglycemic ZF rats. In our ZF rat colony, we incidentally found fa/fa homozygous male rats having reproductive ability, which is generally absent in these animals. During maintenance of this strain by mating fa/fa males and fa/+ heterozygous females, we further identified fa/fa male rats exhibiting diabetes. We then performed selective breeding using the fa/fa male rats that exhibited relatively high blood glucose levels at 10 weeks of age, resulting in establishment of a diabetic strain that we designated Hos:ZFDM-Leprfa (ZFDM. These fa/fa male rats developed diabetes as early as 10 weeks of age, reaching 100% incidence by 21 weeks of age, while none of the fa/+ male rats developed diabetes. The phenotypic characteristics of this diabetic strain are distinct from those of normoglycemic ZF rats. ZFDM rat strain having high reproductive efficiency should serve as a more useful animal model of T2D.

  14. Experimental Salmonella typhimurium infections in rats. I

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1989-01-01

    The course of experimentally induced Salmonella typhimurium infection was studied in three groups of inbred LEW rats: homozygous +/+, athymic rnu/rnu and isogeneic thymus-grafted rnu/rnu rats. In the first experiment the animals were inoculated intraperitoneally with 10(8) bacteria and all animal...

  15. Automatic Training of Rat Cyborgs for Navigation

    Directory of Open Access Journals (Sweden)

    Yipeng Yu

    2016-01-01

    Full Text Available A rat cyborg system refers to a biological rat implanted with microelectrodes in its brain, via which the outer electrical stimuli can be delivered into the brain in vivo to control its behaviors. Rat cyborgs have various applications in emergency, such as search and rescue in disasters. Prior to a rat cyborg becoming controllable, a lot of effort is required to train it to adapt to the electrical stimuli. In this paper, we build a vision-based automatic training system for rat cyborgs to replace the time-consuming manual training procedure. A hierarchical framework is proposed to facilitate the colearning between rats and machines. In the framework, the behavioral states of a rat cyborg are visually sensed by a camera, a parameterized state machine is employed to model the training action transitions triggered by rat’s behavioral states, and an adaptive adjustment policy is developed to adaptively adjust the stimulation intensity. The experimental results of three rat cyborgs prove the effectiveness of our system. To the best of our knowledge, this study is the first to tackle automatic training of animal cyborgs.

  16. Attachment in rat pups, an experimental approach

    NARCIS (Netherlands)

    Gispen, W.H.; Sigling, H.; Engeland, H. van; Spruijt, B.M.

    1998-01-01

    John Bowlby's attachment theory states that attachment behavior has been strengthened throughout evolution as a consequence of its adaptive value. We investigated the presence of attachment-like behavior in rat pups, by offering a choice between the home nest and a same aged other nest. Rat pups sho

  17. Autoprotection in acetaminophen intoxication in rats

    DEFF Research Database (Denmark)

    Dalhoff, K; Laursen, H; Bangert, K;

    2001-01-01

    Autoprotection by acetaminophen, i.e. increased resistance to toxic effects caused by pretreatment, is a well-known phenomenon. The purpose of the present work was to identify mechanisms for increased acetaminophen tolerance induced by pretreatment of rats. One group of female Wistar rats (pretre...

  18. Grooming behavior of spontaneously hypertensive rats

    NARCIS (Netherlands)

    Buuse, M. van den; Jong, Wybren de

    1987-01-01

    In an open field spontaneously hypertensive rats (SHR) exhibited lower scores for grooming when compared to their normotensive controls, the Wistar Kyoto rats (WKY). After i.c.v. injection of 1 μg ACTH1–24 cumulative 50-min grooming scores were lower in SHR. Analysis of subscores indicated that the

  19. Multigeneration reproduction study of isomalt in rats.

    Science.gov (United States)

    Waalkens-Berendsen, D H; Koëter, H B; Sinkeldam, E J

    1990-01-01

    The sugar replacer isomalt was fed to Wistar rats of both sexes throughout three successive generations at concentrations of 0, 2.5, 5 and 10% in the diet. A group of rats fed a diet containing 10% sucrose served as an additional control group. The initial mating was of 100 rats of each sex in each group. For subsequent matings 20 rats of each sex from each group were used. For each generation two litters were reared until they were at least 3 wk old. Feeding isomalt to rats for three successive generations did not induce any adverse effects on fertility, reproductive performance or development compared with control animals fed diets containing maize starch and sucrose instead of isomalt. The second litter of third-generation rats was given detailed gross and microscopic examinations 4 wk after weaning. A marked treatment-related change was an increase in the relative weight of the caecum (filled and empty), 4 wk after weaning in the second litter of third-generation rats fed 10% isomalt. There was also an increase in the relative weight of the filled caecum in males of the 5% isomalt group. These findings were not accompanied by diarrhoea or histological changes in the caecum. The results of the present study did not demonstrate any deleterious effects on the reproduction, maternal performance or development of rats fed isomalt at dietary levels of up to 10% over three successive generations.

  20. Characterization of rat lung ICAM-1

    DEFF Research Database (Denmark)

    Beck-Schimmer, B; Schimmer, R C; Schmal, H;

    1998-01-01

    OBJECTIVE AND DESIGN: We expressed soluble rat ICAM-1, generated a polyclonal anti-ICAM-1 antibody, and studied ICAM-1 upregulation in lung inflammatory conditions. Bacterial and baculovirus expression systems were employed. MATERIAL: 250 g adult, male Long Evans rats were used. For in vitro stud...

  1. (E)-1-[2-Hy-droxy-4,6-bis-(meth-oxy-meth-oxy)phen-yl]-3-[3-meth-oxy-4-(meth-oxy-meth-oxy)phen-yl]prop-2-en-1-one.

    Science.gov (United States)

    Chang, Liu-Shuan; Li, Chen-Yang; Zhao, Yan-Mei; Xu, Fang; Gu, Zheng-Yi

    2011-11-01

    The title compound, C(22)H(26)O(9), crystallizes with two independent mol-ecules in the asymmetric unit in which the dihedral angles between the two benzene rings are 21.4 (2) and 5.1 (2)°. An intra-molecular O-H⋯O hydrogen bond occurs in each mol-ecule. Inter-molecular C-H⋯O hydrogen bonds stabilize the crystal structure.

  2. Cryopreservation and orthotopic transplantation of rat ovaries.

    Science.gov (United States)

    Dorsch, Martina; Wedekind, Dirk

    2010-01-01

    The number of rat strains increased considerably in the last decade and will increase continuously during the next years. This requires enough space for maintaining vital strains and techniques for cryobanking, which can be applied not only in specialised rat resource centres but also in regular animal houses. Here we describe an easy and fast method for the cryopreservation and transplantation of frozen-thawed ovaries of the rat. With dimethyl sulfoxide as cryoprotectant rat ovaries can be stored at -196 degrees C for unlimited time. For revitalisation thawed ovaries have to be orthotopically transplanted into appropriate ovarectomised recipients. Reestablishment of the reproductive cycle in the recipients can be confirmed by vaginal cytology shortly after transplantation. The recipients are able to produce 2-3 litters after mating with males of an appropriate strain. Cyropreservation of ovaries thus can be considered a reliable method to preserve scientifically and economically important stocks and strains of rats that are currently not required.

  3. Adrenergic blockade in diabetic and uninephrectomized rats

    DEFF Research Database (Denmark)

    Thulesen, J; Poulsen, Steen Seier; Jørgensen, P E

    1999-01-01

    was comparable. In adrenergic antagonist treated diabetic rats, it was reduced by at least 40% throughout the study period. Uninephrectomy caused a 50% reduction in the urinary excretion of EGF. This was not influenced by treatment with an adrenergic antagonist. After 3 weeks, saline-treated diabetic rats had......The present study reports on the effects of adrenergic blocking agents on the renal growth and on the renal content and urinary excretion of epidermal growth factor (EGF) in streptozotocin-induced diabetic or uninephrectomized rats. Diabetic and uninephrectomized rats were allocated to groups...... treated with either saline or adrenergic antagonists and compared to controls and sham-operated controls, respectively. 24-hour urine samples were obtained on days 7, 14, and 21 and renal tissue samples on day 21. The 24-hour urinary excretion of EGF from controls and saline-treated diabetic rats...

  4. Social exclusion intensifies anxiety-like behavior in adolescent rats.

    Science.gov (United States)

    Lee, Hyunchan; Noh, Jihyun

    2015-05-01

    Social connection reduces the physiological reactivity to stressors, while social exclusion causes emotional distress. Stressful experiences in rats result in the facilitation of aversive memory and induction of anxiety. To determine the effect of social interaction, such as social connection, social exclusion and equality or inequality, on emotional change in adolescent distressed rats, the emotional alteration induced by restraint stress in individual rats following exposure to various social interaction circumstances was examined. Rats were assigned to one of the following groups: all freely moving rats, all rats restrained, rats restrained in the presence of freely moving rats and freely moving rats with a restrained rat. No significant difference in fear-memory and sucrose consumption between all groups was found. Change in body weight significantly increased in freely moving rats with a restrained rat, suggesting that those rats seems to share the stressful experience of the restrained rat. Interestingly, examination of the anxiety-like behavior revealed only rats restrained in the presence of freely moving rats to have a significant increase, suggesting that emotional distress intensifies in positions of social exclusion. These results demonstrate that unequally excluded social interaction circumstances could cause the amplification of distressed status and anxiety-related emotional alteration.

  5. (1S,2R,7R,8S,10R)-9,9-Di­bromo-2,6,6,10-tetra­methyl-1α,2α-ep­oxy­tri­cyclo­[5.5.0.08,10]dodeca­ne

    Science.gov (United States)

    Benharref, Ahmed; El Karroumi, Jamal; El Ammari, Lahcen; Saadi, Mohamed; Berraho, Moha

    2013-01-01

    The title compound, C16H24Br2O, was synthesized from the reaction of β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzo­cyclo­heptene), which was isolated from Atlas cedar (Cedrus atlantica) essential oil, after reaction with di­bromo­carbene. The asymmetric unit contains two independent mol­ecules with similar conformations. Each mol­ecule is built up from fused six-and seven-membered rings and two three-membered rings. In both mol­ecules, the six-membered ring has an envelope conformation with the flap provided by the C atom of the ep­oxy ring, whereas the seven-membered ring displays a chair conformation. The crystal packing is governed only by van der Waals inter­actions. The absolute configuration was established from anomalous dispersion effects. PMID:24046614

  6. Evidence for [18-Crown-6 Na]2[S2O4] in methanol and dissociation to Na2S2O4 and 18-Crown-6 in the solid state; accounting for the scarcity of simple oxy dianion salts of alkali metal crown ethers in the solid state.

    Science.gov (United States)

    Bruna, Pablo J; Greer, Scott; Passmore, Jack; Rautiainen, J Mikko

    2011-02-21

    [18-Crown-6 Na](2)S(2)O(4) complex was prepared in methanol solution but dissociates into 18-Crown-6 ((s)) and Na(2)S(2)O(4 (s)) on removal of the solvent. Evidence for complexation in methanol is supported by a quantitative mass analysis and the dissociation in the solid state by vibrational spectroscopy and powder X-ray diffraction. These observations are accounted for by investigating the energetics of complexation in solution and dissociation in the solid state using calculated density functional theory (DFT) gas phase binding enthalpies and free energies combined with conductor-like screening model (COSMO) solvation energies and lattice enthalpy and free energy terms derived from volume based thermodynamics (VBT). Our calculations show that complexation of alkali metal dianion salts to crown ethers are much less favorable than that of the corresponding monoanion salts in the solid state and that the formation of alkali metal crown complexes of stable simple oxy-dianion (e.g., CO(3)(2-), SO(4)(2-)) salts is unlikely. The roles of complexation with 18-Crown-6 and ion pair formation in the process of dissolution of Na(2)S(2)O(4) to methanol are discussed.

  7. Variation in rat sciatic nerve anatomy: implications for a rat model of neuropathic pain.

    Science.gov (United States)

    Asato, F; Butler, M; Blomberg, H; Gordh, T

    2000-03-01

    We discovered a variation of rat sciatic nerve anatomy as an incidental finding during the anatomical exploration of the nerve lesion site in a rat neuropathic pain model. To confirm the composition and distribution of rat sciatic nerve, macroscopic anatomical investigation was performed in both left and right sides in 24 adult Sprague-Dawley rats. In all rats, the L4 and L5 spinal nerves were fused tightly to form the sciatic nerve. However, the L6 spinal nerve did not fuse with this nerve completely as a part of the sciatic nerve, but rather sent a thin branch to it in 13 rats (54%), whereas in the remaining 11 rats (46%), L6 ran separately along with the sciatic nerve. Also, the L3 spinal nerve sent a thin branch to the L4 spinal nerve or sciatic nerve in 6 rats (25%). We conclude that the components of sciatic nerve in Sprague-Dawley rats vary from L3 to L6; however, the major components are L4 and L5 macroscopically. This finding is in contrast to the standard textbooks of rat anatomy which describe the sciatic nerve as having major contributions from L4, L5, and L6.

  8. Diminished hormonal responses to exercise in trained rats

    DEFF Research Database (Denmark)

    Galbo, H; Richter, Erik; Holst, J J

    1977-01-01

    Male rats (120 g) either were subjected to a 12-wk physical training program (T rats) or were sedentary controls (C rats). Subsequently the rats were killed at rest or after a 45- or 90-min forced swim. At rest, T rats had higher liver and muscle glycogen concentrations but lower plasma insulin....... In trained rats the hormonal response to exercise is blunted partly due to higher glucose concentrations. In these rats adipose tissue sensitivity to catecholamines is increased, and changes in glucagon and insulin concentrations are not necessary for increased lipolysis and hepatic glycogen depletion during...

  9. Characteristic anatomical structures of rat temporal bone

    Institute of Scientific and Technical Information of China (English)

    Peng Li; Kelei Gao; Dalian Ding; Richard Salvi

    2015-01-01

    As most gene sequences and functional structures of internal organs in rats have been well studied, rat models are widely used in experi-mental medical studies. A large number of descriptions and atlas of the rat temporal bone have been published, but some detailed anatomy of its surface and inside structures remains to be studied. By focusing on some unique characteristics of the rat temporal bone, the current paper aims to provide more accurate and detailed information on rat temporal bone anatomy in an attempt to complete missing or unclear areas in the existed knowledge. We also hope this paper can lay a solid foundation for experimental rat temporal bone surgeries, and promote information exchange among colleagues, as well as providing useful guidance for novice researchers in the field of hearing research involving rats. Copyright © 2015 The Authors. Production & hosting by Elsevier (Singapore) Pte Ltd On behalf of PLA General Hospital Department of Otolaryngology Head and Neck Surgery. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  10. Epidermal growth factor reactivity in rat milk

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Tollund, L

    1990-01-01

    whey elutes as a broad peak corresponding to a Stokes radius of 4.0 nm (an approximate molecular weight of 80 kDa). Almost no 6 kDa EGF is present. Judged by gel filtration of whey pre-incubated with 125I-EGF (6 kDa), no binding protein for EGF is present in rat whey. When rat milk is incubated......The concentration of EGF immunoreactivity in rat whey increases from 0.3 pmol/ml at lactation day 1 to 2.0 pmol/ml at lactation day 19. The concentration of EGF is not influenced when the rats undergo sialoadenectomy prior to mating. On S-200 gel chromatography, almost all EGF-reactivity in rat...... in rat whey behaves as a peptide with a Stokes radius of 2.7 nm, corresponding to a molecular weight of approximately 35 kDa at gel filtration. Comparative binding studies between EGF purified from the submandibular glands and the EGF purified from rat whey confirm differences in the binding...

  11. Embryolethality of butyl benzyl phthalate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Ema, N.; Itami, T.; Kawasaki, H. (National Inst. Hyg. Science, Osaka (Japan))

    1991-03-15

    The developmental toxicity of butyl benzyl phthalate (BBP) was studied in Wistar rats. Pregnant rats were given BBP at a dosage of 0, 0.25, 0.5, 1.0 or 2.0% in the diet from day 0 to day 20 of pregnancy. Morphological examinations of the fetuses revealed no evidence of teratogenesis. In the 2.0% group, all dams exhibited complete resorption of all the implanted embryos, and their food consumption, body weight gain and adjusted weight gain during pregnancy were markedly lowered. To determine whether the embryolethality was the result of reduced food consumption during pregnancy, a pair-feeding study was performed in which the pregnant rats received the same amount of diet consumed by the 2.0% BBP-treated pregnant rats. The pair-fed and 2.0 % BBP-treated pregnant rats showed significant and comparable reductions in the adjusted weight gain. The number of live fetuses was lowered in the pair-fed group. However, the complete resorption of all the implanted embryos was not found in any of the pair-fed pregnant rats. The data suggest that the embryolethality observed in the 2.0 % BBP-treated pregnant rats is attributable to the effects o dietary BBP.

  12. Lessons From Experiments in Rats

    Directory of Open Access Journals (Sweden)

    Albert Gramsbergen

    2001-01-01

    Full Text Available In this essay a few relevant aspects of the neural and behavioral development of the brain in the human and in the rat are reviewed and related to the consequences of lesions in the central and peripheral nervous system at early and later age. Movements initially are generated by local circuits in the spinal cord and without the involvement of descending projections. After birth, both in humans and in rats it seems that the devlopment of postural control is the limiting factor for several motor behaviors to mature. Strong indications exist that the cerebellum is significantly involved in this control. Lesions in the CNS at early stages interfere with fundamental processes of neural development, such as the establishment of fiber connections and cell death patterns. Consequently, the functional effects are strongly dependent on the stage of development. The young and undisturbed CNS, on the other hand, has a much greater capacity than the adult nervous system for compensating abnormal reinnervation in the peripheral nervous system. Animal experiments indicated that the cerebellar cortex might play an important part in this compensation. This possibility should be investigated further as it might offer important perspectives for treatment in the human.

  13. Culture of cryopreserved rat hepatocyte

    Institute of Scientific and Technical Information of China (English)

    Haitao Yin; Gaojun Teng; Lifeng Wang; Baorui Liu; Xiaoping Qian

    2006-01-01

    Objective: To study the method of cryopreserving rat hepatocytes and double collagen gel culture measurement after its cryopreservation. Methods: Rat hepatocytes, isolated by two-step perfusion with collagenase using an extra corporeal perfusion apparatus, were cryopreserved in double collagen gel with culture medium added by epidermal growth factor(EGF).The expression of cell function and cellular morphology were examined during culture. Results: The hepatocytes cryopreserved in double collagen gel concluding EGF showed good morphology and biological characteristics. After thawing, the MTT metabolism and protein synthesis of hepatocytes in sandwich ± EGF groups were better than those in control group. And the morphology and function of hepatocytes in sandwich group was better than that in EGF group(P < 0.05). Conclusion: Double collagen gel culture can keep hepatocyte's activities. Thawed hepatocytes can be cultivated with collagenous matrix, which provides an environment that more closely resembles that in vivo and maintain the expression of certain liver-specific function of hepatocytes.

  14. Population Structure of Rat-Derived Pneumocystis carinii in Danish Wild Rats

    DEFF Research Database (Denmark)

    Palmer, Robert J.; Settnes, Osvald P.; Lodal, Jens

    2000-01-01

    samples. We report a lack of variation in the ITS1 and ITS2 regions that is consistent with an evolutionary bottleneck in the P. carinii f. sp. carinii population. This study shows that human- and rat-derived P. carinii organisms are very different, not population. This study shows that human- and rat......The rat model of Pneumocystis carinii pneumonia is frequently used to study human P. carinii infection, but there are many differences between the rat and human infections. We studied naturally acquired P. carinii in wild rats to examine the relevance of the rat model for human infection. P......-derived organisms are very different, not only in genetic composition but also in population structure and natural history....

  15. Efficient single nucleotide polymorphism discovery in laboratory rat strains using wild rat-derived SNP candidates

    OpenAIRE

    Hedrich Hans J; Wedekind Dirk; Zeegers Dimphy; Guryev Victor; Smits Bart MG; Cuppen Edwin

    2005-01-01

    Abstract Background The laboratory rat (Rattus norvegicus) is an important model for studying many aspects of human health and disease. Detailed knowledge on genetic variation between strains is important from a biomedical, particularly pharmacogenetic point of view and useful for marker selection for genetic cloning and association studies. Results We show that Single Nucleotide Polymorphisms (SNPs) in commonly used rat strains are surprisingly well represented in wild rat isolates. Shotgun ...

  16. Establishment of a novel dwarf rat strain: cartilage calcification insufficient (CCI) rats.

    Science.gov (United States)

    Tanaka, Masami; Watanabe, Minoru; Yokomi, Izuru; Matsumoto, Naoki; Sudo, Katsuko; Satoh, Hitoshi; Igarashi, Tsuneo; Seki, Azusa; Amano, Hitoshi; Ohura, Kiyoshi; Ryu, Kakei; Shibata, Shunichi; Nagayama, Motohiko; Tanuma, Jun-ichi

    2015-01-01

    Rats with dwarfism accompanied by skeletal abnormalities, such as shortness of the limbs, tail, and body (dwarf rats), emerged in a Jcl-derived Sprague-Dawley rat colony maintained at the Institute for Animal Experimentation, St. Marianna University Graduate School of Medicine. Since the dwarfism was assumed to be due to a genetic mutation based on its frequency, we bred the dwarf rats and investigated their characteristics in order to identify the causative factors of their phenotypes and whether they could be used as a human disease model. One male and female that produced dwarf progeny were selected, and reproduction was initiated by mating the pair. The incidence of dwarfism was 25.8% among the resultant litter, and dwarfism occurred in both genders, suggesting that it was inherited in an autosomal recessive manner. At 12 weeks of age, the body weights of the male and female dwarf rats were 40% and 57% of those of the normal rats, respectively. In soft X-ray radiographic and histological examinations, shortening and hypoplasia of the long bones, such as the tibia and femur, were observed, which were suggestive of endochondral ossification abnormalities. An immunohistochemical examination detected an aggrecan synthesis disorder, which might have led to delayed calcification and increased growth plate thickening in the dwarf rats. We hypothesized that the principal characteristics of the dwarf rats were systemically induced by insufficient cartilage calcification in their long bones; thus, we named them cartilage calcification insufficient (CCI) rats.

  17. Efficient single nucleotide polymorphism discovery in laboratory rat strains using wild rat-derived SNP candidates

    Directory of Open Access Journals (Sweden)

    Hedrich Hans J

    2005-11-01

    Full Text Available Abstract Background The laboratory rat (Rattus norvegicus is an important model for studying many aspects of human health and disease. Detailed knowledge on genetic variation between strains is important from a biomedical, particularly pharmacogenetic point of view and useful for marker selection for genetic cloning and association studies. Results We show that Single Nucleotide Polymorphisms (SNPs in commonly used rat strains are surprisingly well represented in wild rat isolates. Shotgun sequencing of 814 Kbp in one wild rat resulted in the identification of 485 SNPs as compared with the Brown Norway genome sequence. Genotyping 36 commonly used inbred rat strains showed that 84% of these alleles are also polymorphic in a representative set of laboratory rat strains. Conclusion We postulate that shotgun sequencing in a wild rat sample and subsequent genotyping in multiple laboratory or domesticated strains rather than direct shotgun sequencing of multiple strains, could be the most efficient SNP discovery approach. For the rat, laboratory strains still harbor a large portion of the haplotypes present in wild isolates, suggesting a relatively recent common origin and supporting the idea that rat inbred strains, in contrast to mouse inbred strains, originate from a single species, R. norvegicus.

  18. Rats are the smart choice: Rationale for a renewed focus on rats in behavioral genetics.

    Science.gov (United States)

    Parker, Clarissa C; Chen, Hao; Flagel, Shelly B; Geurts, Aron M; Richards, Jerry B; Robinson, Terry E; Solberg Woods, Leah C; Palmer, Abraham A

    2014-01-01

    Due in part to their rich behavioral repertoire rats have been widely used in behavioral studies of drug abuse-related traits for decades. However, the mouse became the model of choice for researchers exploring the genetic underpinnings of addiction after the first mouse study was published demonstrating the capability of engineering the mouse genome through embryonic stem cell technology. The sequencing of the mouse genome and more recent re-sequencing of numerous inbred mouse strains have further cemented the status of mice as the premier mammalian organism for genetic studies. As a result, many of the behavioral paradigms initially developed and optimized for rats have been adapted to mice. However, numerous complex and interesting drug abuse-related behaviors that can be studied in rats are very difficult or impossible to adapt for use in mice, impeding the genetic dissection of those traits. Now, technological advances have removed many of the historical limitations of genetic studies in rats. For instance, the rat genome has been sequenced and many inbred rat strains are now being re-sequenced and outbred rat stocks are being used to fine-map QTLs. In addition, it is now possible to create "knockout" rats using zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALENs) and related techniques. Thus, rats can now be used to perform quantitative genetic studies of sophisticated behaviors that have been difficult or impossible to study in mice. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.

  19. The rat STSL locus: characterization, chromosomal assignment, and genetic variations in sitosterolemic hypertensive rats

    Directory of Open Access Journals (Sweden)

    Klein Richard

    2003-06-01

    Full Text Available Abstract Background Elevated plant sterol accumulation has been reported in the spontaneously hypertensive rat (SHR, the stroke-prone spontaneously hypertensive rat (SHRSP and the Wistar-Kyoto (WKY rat. Additionally, a blood pressure quantitative trait locus (QTL has been mapped to rat chromosome 6 in a New Zealand genetically hypertensive rat strain (GH rat. ABCG5 and ABCG8 (encoding sterolin-1 and sterolin-2 respectively have been shown to be responsible for causing sitosterolemia in humans. These genes are organized in a head-to-head configuration at the STSL locus on human chromosome 2p21. Methods To investigate whether mutations in Abcg5 or Abcg8 exist in SHR, SHRSP, WKY and GH rats, we initiated a systematic search for the genetic variation in coding and non-coding region of Abcg5 and Abcg8 genes in these strains. We isolated the rat cDNAs for these genes and characterized the genomic structure and tissue expression patterns, using standard molecular biology techniques and FISH for chromosomal assignments. Results Both rat Abcg5 and Abcg8 genes map to chromosome band 6q12. These genes span ~40 kb and contain 13 exons and 12 introns each, in a pattern identical to that of the STSL loci in mouse and man. Both Abcg5 and Abcg8 were expressed only in liver and intestine. Analyses of DNA from SHR, SHRSP, GH, WKY, Wistar, Wistar King A (WKA and Brown Norway (BN rat strains revealed a homozygous G to T substitution at nucleotide 1754, resulting in the coding change Gly583Cys in sterolin-1 only in rats that are both sitosterolemic and hypertensive (SHR, SHRSP and WKY. Conclusions The rat STSL locus maps to chromosome 6q12. A non-synonymous mutation in Abcg5, Gly583Cys, results in sitosterolemia in rat strains that are also hypertensive (WKY, SHR and SHRSP. Those rat strains that are hypertensive, but not sitosterolemic (e.g. GH rat do not have mutations in Abcg5 or Abcg8. This mutation allows for expression and apparent apical targeting of Abcg5

  20. Rat embryonic stem cells create new era in development of genetically manipulated rat models

    Institute of Scientific and Technical Information of China (English)

    Kazushi; Kawaharada; Masaki; Kawamata; Takahiro; Ochiya

    2015-01-01

    Embryonic stem(ES) cells are isolated from theinner cell mass of a blastocyst, and are used for the generation of gene-modified animals. In mice, the transplantation of gene-modified ES cells into recipient blastocysts leads to the creation of gene-targeted mice such as knock-in and knock-out mice; these gene-targeted mice contribute greatly to scientific development. Although the rat is considered a useful laboratory animal alongside the mouse, fewer genemodified rats have been produced due to the lack of robust establishment methods for rat ES cells. A new method for establishing rat ES cells using signaling inhibitors was reported in 2008. By considering the characteristics of rat ES cells, recent research has made progress in improving conditions for the stable culture of rat ES cells in order to generate gene-modified rats efficiently. In this review, we summarize several advanced methods to maintain rat ES cells and generate gene-targeted rats.

  1. Response of substances co-expressed in hypothalamic magnocellular neurons to osmotic challenges in normal and Brattleboro rats

    DEFF Research Database (Denmark)

    Bundzikova, J.; Pirnik, Z.; Zelena, D.;

    2008-01-01

    The intention of this review is to emphasize the current knowledge about the extent and importance of the substances co-localized with magnocellular arginine vasopressin (AVP) and oxytocin (OXY) as potential candidates for the gradual clarification of their actual role in the regulation of hydrom...

  2. Quantification of the beta-adrenoceptor ligand S-1'[F-18]fluorocarazolol in plasma of humans, rats and sheep

    NARCIS (Netherlands)

    vanWaarde, A; Posthumus, H; Elsinga, PH; Anthonio, RL; van Loenen - Weemaes, Anne-miek; Beaufort-Krol, Gertie C. M.; Paans, AMJ; Vaalburg, W; Visser, Thomas; Visser, Gerben

    1996-01-01

    Myocardial and pulmonary beta-adrenoceptors can be imaged with 2-(S)-(-)-(9H-carbazol-4-yl-oxy)-3-[1-(fluoromethyl)ethyl]amino-2-propanol (S-1'-[F-18]fluorocarazolol, I). Quantification of unmodified fluorocarazolol in plasma is necessary for analysis of PET images in terms of receptor densities. We

  3. Rat sperm motility analysis: methodologic considerations

    Science.gov (United States)

    The objective of these studies was to optimize conditions for computer-assisted sperm analysis (CASA) of rat epididymal spermatozoa. Methodologic issues addressed include sample collection technique, sampling region within the epididymis, type of diluent medium used, and sample c...

  4. A Music Preference Test System for Rats

    Institute of Scientific and Technical Information of China (English)

    Chun-Peng Zhang; Guang-Zhan Fang; Yang Xia; Tie-Jun Liu; De-Zhong Yao

    2009-01-01

    In music preference experiments,housing conditions and the control of parameters for animals can affect experimental results.However,the needs of animals are indeed insufficiently considered in many reports of animal experiments.In order to evaluate which music rats prefer,we developed a new music preference test system.Dwelling time and visiting frequency can be recorded automatically when rats moving among different compartments of the system.We can also observe the behaviors of rats captured by a video camera.By this system,the music preference can be found,and then the related music can be used in following various studies.In this paper,we described the design of this music preference test system of rat,and some primary results were reported.

  5. Hypergravity induced prolactin surge in female rats

    Science.gov (United States)

    Megory, E.; Oyama, J.

    1985-01-01

    Acute initial exposure to hypergravity (HG) was previously found to induce prolonged diestrous in rats, which was followed by return to normal estrous cycling upon more prolonged exposure to continuous HG. Bromergocryptine was found to prevent this prolonged diestrous. In this study it is found that in female rats 20 h of 3.14 G exposure (D-1 1200 h until D-2 0800 h) can induce prolactin surge at D-2 1600 h. Shorter exposure time (8 h), or exposure during a different part of the estrous cycle (19 h: from D-1 0700 h until D-2 0200 h) could not elicit this prolactin surge. Similar exposure of male rats of HG did not alter significantly their prolactin levels. It is possible that the hypothalamus of male and female rats responds differently to stimulation by HG.

  6. Penile autotransplantation in rats: An animal model

    Directory of Open Access Journals (Sweden)

    Raouf M Seyam

    2013-01-01

    Conclusions: Penile autotransplantation in rats is feasible and provides the basis for evaluation of the corpora cavernosa in an allotransplantation model. Long-term urethral continuity and dorsal neurovascular bundle survival in this model is difficult to establish.

  7. Rat Bite Fever Resembling Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Ripa Akter

    2016-01-01

    Full Text Available Rat bite fever is rare in Western countries. It can be very difficult to diagnose as blood cultures are typically negative and a history of rodent exposure is often missed. Unless a high index of suspicion is maintained, the associated polyarthritis can be mistaken for rheumatoid arthritis. We report a case of culture-positive rat bite fever in a 46-year-old female presenting with fever and polyarthritis. The clinical presentation mimicked rheumatoid arthritis. Infection was complicated by discitis, a rare manifestation. We discuss the diagnosis and management of this rare zoonotic infection. We also review nine reported cases of rat bite fever, all of which had an initial presumptive diagnosis of a rheumatological disorder. Rat bite fever is a potentially curable infection but can have a lethal course if left untreated.

  8. Intestinal microecology in rats with ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    韩晓霞

    2013-01-01

    Objective To study the abundance and diversity ofthe gut flora in rats with dextran sulfate sodium(DSS)-induced ulcerative colitis(UC)to provide new knowledge about the pathogenesis of this disease.Methods Twenty-six

  9. [Individual sensitivity of Wistar rats to piracetam].

    Science.gov (United States)

    Nikol'skaia, K A; Kondrashevskaia, M V; Eremina, L V

    2007-11-01

    Effects of repeated piracetam (PIR) injections in a dose of 40 and 250 mg/kg/day on the learning in Water rats were studied. It has been found that character of the effects depends on typological features of the animals. Rats with strong predominance of excitation (choleric type) showed low sensitivity to PIR. Small dose of PIR provoked clear negative effect in rats with relative balance of the basic nervous processes: excitation and inhibition (sanguine and phlegmatic types). Despite of expressed activation of associative process, it complicated integrative activity. Small dose of PIR showed anxiolytic and psycho-stimulant actions only in initially unlearned rats characterized by high level of fear. Large dose of PIR had negative influence on the learning process in all animals, irrespective of typological features. Thus, the results of this study allow to suppose that the individual sensitivity of an animal to action of a pharmacological medication is caused by morpho-functional and neurochemical intraspecific heterogeneity.

  10. Alveolar ridge augmentation by osteoinduction in rats

    DEFF Research Database (Denmark)

    Pinholt, E M; Bang, G; Haanaes, H R

    1990-01-01

    performed subperiosteally on the premaxilla and heterotopically in the abdominal muscles of rats. Light microscopic evaluations revealed that all allogenic, demineralized, and lyophilized dentin and bone implants induced new bone formation. No inflammatory or foreign body reactions were observed....

  11. Expression of somatostatin mRNA and peptide in rat hippocampus after cerebral ischemia

    DEFF Research Database (Denmark)

    Bering, Robert; Johansen, Flemming Fryd

    1993-01-01

    Somatostatin, ischemia, hippocampus, rat, in situ hybridisation, immunocytochemistry, neuropathology......Somatostatin, ischemia, hippocampus, rat, in situ hybridisation, immunocytochemistry, neuropathology...

  12. How rats combine temporal cues.

    Science.gov (United States)

    Guilhardi, Paulo; Keen, Richard; MacInnis, Mika L M; Church, Russell M

    2005-05-31

    The procedures for classical and operant conditioning, and for many timing procedures, involve the delivery of reinforcers that may be related to the time of previous reinforcers and responses, and to the time of onsets and terminations of stimuli. The behavior resulting from such procedures can be described as bouts of responding that occur in some pattern at some rate. A packet theory of timing and conditioning is described that accounts for such behavior under a wide range of procedures. Applications include the food searching by rats in Skinner boxes under conditions of fixed and random reinforcement, brief and sustained stimuli, and several response-food contingencies. The approach is used to describe how multiple cues from reinforcers and stimuli combine to determine the rate and pattern of response bouts.

  13. Modeling diabetic sensory neuropathy in rats.

    Science.gov (United States)

    Calcutt, Nigel A

    2004-01-01

    The procedures to induce insulin-deficient diabetes in rats using streptozotocin are described along with a number of insulin treatment regimes that can be used to maintain these animals at different degrees of glycemia for periods of weeks to months. Streptozotocin-diabetic rats develop tactile allodynia, hyperalgesia following paw formalin injection and abnormal responses to thermal stimulation and the detailed methods used to evaluate these behavioral indices of abnormal sensory function are provided.

  14. Collagenous skeleton of the rat mystacial pad.

    Science.gov (United States)

    Haidarliu, Sebastian; Simony, Erez; Golomb, David; Ahissar, Ehud

    2011-05-01

    Anatomical and functional integrity of the rat mystacial pad (MP) is dependent on the intrinsic organization of its extracellular matrix. By using collagen autofluorescence, in the rat MP, we revealed a collagenous skeleton that interconnects whisker follicles, corium, and deep collagen layers. We suggest that this skeleton supports MP tissues, mediates force transmission from muscles to whiskers, facilitates whisker retraction after protraction, and limits MP extensibility.

  15. Streptozotocin induced diabetes in lyon hypertensive rats

    Institute of Scientific and Technical Information of China (English)

    LeaEMONNOT; JeanSASSARD; MingLO

    2004-01-01

    AIM: Lyon hypertensive (LH) rats, compared to their normotensive controls (LL) exhibit an increased blood pressure (BP)associated with a marked proteinuria and a metabolic syndrom including elevated plasma lipids and insulin/glucose ratio. The aim of the present work was to determine wether a type 2 diabetes could be induced in LH rats so as to obtain a model suitable for study of the relationships between diabetes and hypertension.

  16. Experimental coccidioidomycosis in the immunosuppressed rat

    OpenAIRE

    Mirta C. Remesar; Jorgelina L. Blejer; Negroni,Ricardo; Nejamkis,Marta R.

    1992-01-01

    C. immitis inoculated rats are known to develop infection restricted to lung whereas cyclophosphamide (CY) treatment leads to widespread dissemination with considerable mortality. In this study, an attempt was made to elucidate the mechanisms involved in such behaviour. With this aim, spleen cells were transferred from infected CY-treated to infected untreated rats, achieving significant specific inhibition in footpad swelling to coccidioidin in recipients, attributable to a suppressor T cell...

  17. Experimental model of anal fistula in rats

    OpenAIRE

    Arakaki, Mariana Sousa; Santos,Carlos Henrique Marques dos; Falcão, Gustavo Ribeiro; Cassino,Pedro Carvalho; Nakamura, Ricardo Kenithi; Gomes,Nathália Favero; Santos,Ricardo Gasparin Coutinho dos

    2013-01-01

    INTRODUCTION: the management of anal fistula remains debatable. The lack of a standard treatment free of complications stimulates the development of new options. OBJECTIVE: to develop an experimental model of anal fistula in rats. METHODS: to surgically create an anal fistula in 10 rats with Seton introduced through the anal sphincter musculature. The animals were euthanized for histological fistula tract assessment. RESULTS: all ten specimens histologically assessed had a lumen and surroundi...

  18. MODELING OPERANT BEHAVIOR IN THE PARKINSONIAN RAT

    OpenAIRE

    Avila, Irene; Reilly, Mark P; Sanabria, Federico; Posadas-Sánchez, Diana; Chavez, Claudia L.; Banerjee, Nikhil; Killeen, Peter; Castañeda, Edward

    2008-01-01

    Mathematical principles of reinforcement (MPR; Killeen, 1994) is a quantitative model of operant behavior that contains 3 parameters representing motor capacity (δ), motivation (a), and short term memory (λ). The present study applied MPR to characterize the effects of bilateral infusions of 6-OHDA into the substantia nigra pars compacta in the rat, a model of Parkinson’s disease. Rats were trained to lever press under a 5-component fixed ratio (5, 15, 30, 60, and 100) schedule of food reinfo...

  19. A digital rat atlas of sectional anatomy

    Science.gov (United States)

    Yu, Li; Liu, Qian; Bai, Xueling; Liao, Yinping; Luo, Qingming; Gong, Hui

    2006-09-01

    This paper describes a digital rat alias of sectional anatomy made by milling. Two healthy Sprague-Dawley (SD) rat weighing 160-180 g were used for the generation of this atlas. The rats were depilated completely, then euthanized by Co II. One was via vascular perfusion, the other was directly frozen at -85 °C over 24 hour. After that, the frozen specimens were transferred into iron molds for embedding. A 3% gelatin solution colored blue was used to fill the molds and then frozen at -85 °C for one or two days. The frozen specimen-blocks were subsequently sectioned on the cryosection-milling machine in a plane oriented approximately transverse to the long axis of the body. The surface of specimen-blocks were imaged by a scanner and digitalized into 4,600 x2,580 x 24 bit array through a computer. Finally 9,475 sectional images (arterial vessel were not perfused) and 1,646 sectional images (arterial vessel were perfused) were captured, which made the volume of the digital atlas up to 369.35 Gbyte. This digital rat atlas is aimed at the whole rat and the rat arterial vessels are also presented. We have reconstructed this atlas. The information from the two-dimensional (2-D) images of serial sections and three-dimensional (3-D) surface model all shows that the digital rat atlas we constructed is high quality. This work lays the foundation for a deeper study of digital rat.

  20. Epidermal growth factor in the rat prostate

    DEFF Research Database (Denmark)

    Tørring, Niels; Jørgensen, P E; Poulsen, Steen Seier;

    1998-01-01

    Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate.......Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate....