WorldWideScience

Sample records for oral sulfur-containing gases

  1. Associations among hair loss, oral sulfur-containing gases, and gastrointestinal and metabolic linked diseases in Japanese elderly men: pilot study

    Hamasaki Tomoko

    2009-03-01

    Full Text Available Abstract Background Male pattern baldness (MPB, an observable trait, has been reported to be associated with various diseases, such as prostate cancer and cardiovascular disease. Oral sulfur-containing gases have also been suggested to be useful as markers of systemic health condition. However, there are no known reports regarding the associations among MPB, and oral sulfur-containing gases, and systemic health conditions in males. Methods We studied 170 male subjects aged either 60 or 65 years old. The degree of MPB was assessed using the Norwood-Hamilton Baldness scale. Oral sulfur-containing gases were measured using a compact-designed device. All subjects completed physical and laboratory blood examinations, a face-to-face medical questionnaire, and an oral examination. Results There were significant differences between the levels of CH3SCH3 and baldness patterns, independent of age. When we analyzed whether the association was linked to systemic health condition, a strong significant association was observed between the level of CH3SCH3 and severe MPB in subjects with gastrointestinal diseases, hypertension, and hypercholesterolemia. Conclusion These results suggest that MPB is associated with the level of CH3SCH3, a sulfur-containing gas that causes oral malodor, in elderly Japanese males. Further, the association was intensified by the existence of gastrointestinal tract and metabolic disorders.

  2. New treating processes for sulfur-containing natural gases

    Kislenko, N.; Aphanasiev, A.; Nabokov, S.; Ismailova, H. [VNIIGAS, Moscow (Russian Federation)

    1996-12-31

    The traditional method of removing H{sub 2}S from sour natural gases is first to treat the gas with a solvent and then to recover the H{sub 2}S from the sour stream in a Claus plant. This method recovers up to 97% of the sulfur when a three-stage Claus unit is employed. Amine/Claus units have operating difficulties for small sulfur capacities (up to 5 tons/day) because the operation of the fired equipment (reaction furnace) is much more difficult. Therefore, for small scale sulfur recovery plants redox processes which exhibit a significant reduction in investment and operating costs are normally used. Many different factors influence the choice of gas desulfurization technology--composition and gas flow, environmental sulfur recovery requirements and CO{sub 2}/H{sub 2}S ratio.

  3. Effects of mineral matters on evolution of sulfur-containing gases in pyrolysis and hydropyrolysis

    Chen, H.; Li, B.; Zhang, B. [Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan (China). State Key Lab. of Coal Conversion

    1998-07-01

    The evolution of sulfur-containing gases were investigated using two Chinese coals with their de-ash and de-pyrite forms in pyrolysis and hydropyrolysis. Mineral matter can not only return H{sub 2}S produced in pyrolysis and hydropyrolysis, but also catalyse hydrodesulfurization and reduce COS formation. Secondary reactions markedly influence COS formation. Mineral matter can reduce CH{sub 3}SH formation, and pyrite shows positive effects on CH{sub 3}SH formation. 7 refs., 6 figs., 1 tab.

  4. Process for removing sulfur from sulfur-containing gases: high calcium fly-ash

    Rochelle, Gary T.; Chang, John C. S.

    1991-01-01

    The present disclosure relates to improved processes for treating hot sulfur-containing flue gas to remove sulfur therefrom. Processes in accordance with the present invention include preparing an aqueous slurry composed of a calcium alkali source and a source of reactive silica and/or alumina, heating the slurry to above-ambient temperatures for a period of time in order to facilitate the formation of sulfur-absorbing calcium silicates or aluminates, and treating the gas with the heat-treated slurry components. Examples disclosed herein demonstrate the utility of these processes in achieving improved sulfur-absorbing capabilities. Additionally, disclosure is provided which illustrates preferred configurations for employing the present processes both as a dry sorbent injection and for use in conjunction with a spray dryer and/or bagfilter. Retrofit application to existing systems is also addressed.

  5. Sulfur-Containing Agrochemicals.

    Devendar, Ponnam; Yang, Guang-Fu

    2017-10-09

    Modern agricultural chemistry has to support farmers by providing innovative agrochemicals. In this context, the introduction of sulfur atoms into an active ingredient is still an important tool in modulating the properties of new crop-protection compounds. More than 30% of today's agrochemicals contain at least one sulfur atom, mainly in fungicides, herbicides and insecticides. A number of recently developed sulfur-containing agrochemical candidates represent a novel class of chemical compounds with new modes of action, so we intend to highlight the emerging interest in commercially active sulfur-containing compounds. This chapter gives a comprehensive overview of selected leading sulfur-containing pesticidal chemical families namely: sulfonylureas, sulfonamides, sulfur-containing heterocyclics, thioureas, sulfides, sulfones, sulfoxides and sulfoximines. Also, the most suitable large-scale synthetic methods of the recently launched or provisionally approved sulfur-containing agrochemicals from respective chemical families have been highlighted.

  6. A study of sulfur-containing compounds in mouth- and nose-exhaled breath and in the oral cavity using selected ion flow tube mass spectrometry

    Pysanenko, A.; Španěl, Patrik; Smith, D.

    2008-01-01

    Roč. 2, - (2008), 046004-1-13 ISSN 1752-7155 R&D Projects: GA ČR GA202/06/0776 Institutional research plan: CEZ:AV0Z40400503 Keywords : sulfur-containing compounds * SIFT-MS Subject RIV: CF - Physical ; Theoretical Chemistry

  7. Sulfur containing nanoporous materials, nanoparticles, methods and applications

    Archer, Lynden A.; Navaneedhakrishnan, Jayaprakash

    2018-01-30

    Sulfur containing nanoparticles that may be used within cathode electrodes within lithium ion batteries include in a first instance porous carbon shape materials (i.e., either nanoparticle shapes or "bulk" shapes that are subsequently ground to nanoparticle shapes) that are infused with a sulfur material. A synthetic route to these carbon and sulfur containing nanoparticles may use a template nanoparticle to form a hollow carbon shape shell, and subsequent dissolution of the template nanoparticle prior to infusion of the hollow carbon shape shell with a sulfur material. Sulfur infusion into other porous carbon shapes that are not hollow is also contemplated. A second type of sulfur containing nanoparticle includes a metal oxide material core upon which is located a shell layer that includes a vulcanized polymultiene polymer material and ion conducting polymer material. The foregoing sulfur containing nanoparticle materials provide the electrodes and lithium ion batteries with enhanced performance.

  8. Prebiotics mitigate in vitro sulfur-containing odour generation in caecal content of pigs

    Yuan Fan Deng

    2015-03-01

    Full Text Available The objective of this study was to examine the effects and role of prebiotics, such as inulin, fructo-oligosaccharides (FOS and galactooligosaccharides (GAS, to mitigate sulfur-containing odour gases, hydrogen sulfide (H2S and methyl mercaptan (CH3SH using pigs as in vitro study model. Inocula obtained from pigs were incubated at 39°C for 24 h using 550 mg sterilised substrate (caecal contents supplemented with or without 50 mg prebiotics. Production of total gas, H2S and CH3SH were determined. The results showed that total gas production for the caecal content of pigs was 57.3 mL, and that for H2S and CH3SH was 220.2 and 15.2 μL, respectively. The total gas production increased (P<0.05, whereas concentrations of H2S and CH3SH decreased (P<0.05 with supplementation of prebiotics. Among the prebiotics, inulin was the most effective in mitigating H2S and CH3SH productions, reducing the two malodorous gases by 14.7 and 19.8%, respectively. The reduction of the above two sulfur- containing gases was supported by lower sulfate-reducing bacteria population and higher sulfate radical concentrations in the prebiotics, particularly that of inulin supplementation group.

  9. Sulfur equilibrium desulfurization of sulfur containing products of combustion

    Woodroffe, J.A.; Abichandani, J.S.

    1990-01-01

    This patent describes the method for the combustion of a carbon- and sulfur-containing fuel for substantially reducing emission of gaseous sulfur compounds formed during combustion of the fuel in a combustion zone. The zone having one or more fuel inlets and one or more oxidizer inlets, and having a combustion products outlet spaced therefrom, and having one or more inorganic sorbent inlets downstream of the fuel inlet(s) and oxidizer inlet(s) and upstream of the combustion products outlet

  10. Sulfur-containing components of gamma-irradiated garlic bulbs

    Joongho Kwon; Jonguck Choi; Hyungsik Yoon

    1989-01-01

    Sulfur-containing components associated with garlic flavors were investigated to determine the effect of γ-irradiation at 0.1Gy on the quality of garlic bulbs (Allium sativum L.) during storage at 3±1 0 C and 80±5% RH for 10 months. Irradiation treatment had no influence on the amount of total sulfur and thiosulfinate of stored garlic for 10 months, while the storage period brought about a significant reduction (P < 0.05) in the content of both components after the 6-8th month of storage compared with that at the beginning of storage period. The identity of irradiated alliin (S-allyl-L-cysteine sulfoxide) at sprout-inhibition dose was confirmed according to thin-layer chromatography, i.r. and NMR spectroscopy data. (author)

  11. Sulfur-containing components of gamma-irradiated garlic bulbs

    Kwon, Joong-Ho; Choi, Jong-Uck; Yoon, Hyung-Sik

    Sulfur-containing components associated with garlic flavors were investigated to determine the effect of γ-irradiation at 0.1 kGy on the quality of garlic bulbs ( Allium sativum L.) during storage at 3±1°C and 80±5% RH for 10 months. Irradiation treatment had no influence on the amount of total sulfur and thiosulfinate of stored garlic for 10 months, while the storage period brought about a significant reduction ( P<0.05) in the content of both components after the 6-8th month of storage compared with that at the beginning of storage period. The identity of irradiated alliin ( S-allyl- L-cysteine sulfoxide) at sprout-inhibition dose was confirmed according to thin-layer chromatography, i.r. and NMR spectroscopy data.

  12. Interaction between synthetic lecithin and various sulfur-containing radioprotectors

    Rix-Montel, M.A.; Kranck, H.; Vasilescu, D.

    1981-01-01

    Interaction of the synthetic lecithin dipalmitoylphosphatidylcholine (DPPC) smectic mesophases with sulfur-containing radioprotectors was investigated by means of spectrophotometric and dielectric measurements. Electrical conductivity behavior indicated in all cases that an electrostatic interaction occurs between DPPC and the antiradiation drugs. This interaction is very strong in the case of the WR 2721 molecule. Thermal transitions of DPPC studied by spectrophotometry and conductivity Arrhenius diagrams showed that although the radio-protectors investigated (except WR 2721) delete the pretransition of the lipid phase, the principal transition is not modified. The observed electrostatic interactions are discussed with regard to ionized sites of the phosphatidylcholine lipid head and those of the radioprotectors. The special cases of WR 2721 and its metabolite, WR 1065, are examined

  13. Sulfur-containing components of gamma-irradiated garlic bulbs

    Joongho Kwon (Korea Advanced Energy Research Inst., Daeduk (Republic of Korea)); Jonguck Choi; Hyungsik Yoon (Kyungpook National Univ., Taegu (Republic of Korea))

    1989-01-01

    Sulfur-containing components associated with garlic flavors were investigated to determine the effect of {gamma}-irradiation at 0.1Gy on the quality of garlic bulbs (Allium sativum L.) during storage at 3{plus minus}1{sup 0}C and 80{plus minus}5% RH for 10 months. Irradiation treatment had no influence on the amount of total sulfur and thiosulfinate of stored garlic for 10 months, while the storage period brought about a significant reduction (P < 0.05) in the content of both components after the 6-8th month of storage compared with that at the beginning of storage period. The identity of irradiated alliin (S-allyl-L-cysteine sulfoxide) at sprout-inhibition dose was confirmed according to thin-layer chromatography, i.r. and NMR spectroscopy data. (author).

  14. Efficacy and role of inulin in mitigation of enteric sulfur-containing odor in pigs.

    Deng, Yuan-Fan; Liu, Yuan-Yuan; Zhang, Yi-Tao; Wang, Yan; Liang, Juan-Boo; Tufarelli, Vincenzo; Laudadio, Vito; Liao, Xin-Di

    2017-06-01

    The efficacy and role of inulin in the mitigation of enteric sulfur-containing odor gases hydrogen sulfide (H 2 S) and methyl mercaptan (CH 3 SH) in pigs were examined in this study. Twelve Duroc × Landrace × Yorkshire male finisher pigs (60.7 ± 1.9 kg), housed individually in open-circuit respiration chambers, were randomly assigned to two dietary groups, namely basal diet (control) and basal diet supplemented with 1% (w/w) inulin. At the end of the 45 day experiment, pigs were slaughtered and volatile fatty acid (VFA) concentration, sulfate radical (SO 4 2 - ) concentration, population of sulfate-reducing bacteria (SRB) and expression of methionine gamma-lyase (MGL) gene were determined in contents from the caecum, colon (two segments) and rectum. Metabonomic analysis was used to compare differences in biochemical composition, and the Illumina MiSeq procedure to investigate differences in bacterial components, in the different parts of the large intestine between inulin-supplemented and inulin-free (control) groups. Inulin decreased (P inulin treatment, whereas valerate concentration and MGL mRNA expression decreased (P inulin-supplemented pigs, suggesting that inulin mitigates H 2 S generation from the SO 4 2 - reduction pathway by reducing the growth of SRB. The results showed that inulin mitigates CH 3 SH generation via three methionine degradation metabolic pathways and H 2 S generation from two cysteine degradation metabolic pathways, thus resulting in increased synthesis of these two sulfur-containing amino acids in the pig large intestine. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes

    Liu, Huan [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Luo, Guang-Qian; Hu, Hong-Yun [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhang, Qiang; Yang, Jia-Kuan [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yao, Hong, E-mail: hyao@hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer NH{sub 3}, SO{sub 2}, H{sub 2}S and COS are emitted during different sludge conditioning processes. Black-Right-Pointing-Pointer H{sub 2}S and SO{sub 2} generation increase in the acidic environment created by H{sub 2}SO{sub 4}. Black-Right-Pointing-Pointer Fenton peroxidation facilitates the formation of COS. Black-Right-Pointing-Pointer CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. Black-Right-Pointing-Pointer CaO leads to the conversion of free ammonia or protonated amine to volatile NH{sub 3}. - Abstract: Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH{sub 3}), sulfur dioxide (SO{sub 2}), hydrogen sulfide (H{sub 2}S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO{sub 2} and H{sub 2}S emissions in the H{sub 2}SO{sub 4} conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant

  16. Electrical properties of a new sulfur-containing polymer for optoelectronic application

    ElAkemi, ElMehdi; Jaballah, Nejmeddine; Ouada, Hafedh Ben; Majdoub, Mustapha

    2015-06-01

    An original polythiophene derivative was characterized to develop the optoelectronic properties of sulfur-containing π-conjugated polymer. The optical properties of the polymer were investigated by UV-visible absorption spectroscopy and atomic force microscopy. Investigations of the electrical characteristics of polymer diodes are reported. We present current-voltage characteristics and impedance spectroscopy measurements performed on partially sulfur-containing thin films in sandwich structure ITO/sulfur-containing polymer/Al. The conduction mechanisms in these layers are identified to be a space-charge-limited current. The AC electrical transport of the sulfur-containing polymer is studied as a function of frequency (100 Hz-10 MHz) and temperature in impedance spectroscopy analyses. We interpreted Cole-Cole plots in terms of the equivalent circuit model as a single parallel resistance and a capacitance network in series with a relatively small resistance. The evolution of the electrical parameters deduced from fitting of the experimental data is discussed.

  17. Adsorption/oxidation of sulfur-containing gases on nitrogen-doped activated carbon

    Liu Qiang

    2016-01-01

    Full Text Available Coconut shell-based activated carbon (CAC was used for the removal of methyl mercaptan (MM. CAC was modified by urea impregnation and calcined at 450°C and 950°C. The desulfurization activity was determined in a fixed bed reactor under room temperature. The results showed that the methyl mercaptan adsorption/oxidation capacity of modified carbon caicined at 950°C is more than 3 times the capacity of original samples. On the other hand, the modified carbon caicined at 950°C also has a high capacity for the simultaneous adsorption/oxidation of methyl mercaptan and hydrogen sulfide.The introduce of basic nitrogen groups siginificantly increases the desulfurization since it can facilitate the electron transfer process between sulfur and oxygen. The structure and chemical properties are characterized using Boehm titration, N2 adsorption-desorption method, thermal analysis and elemental analysis. The results showed that the major oxidation products were dimethyl disulfide and methanesulfonic acid which adsorbed in the activated carbon.

  18. Inhibition of Enzymatic Browning of Chlorogenic Acid by Sulfur-Containing Compounds

    Kuijpers, T.F.M.; Narvaez Cuenca, C.E.; Vincken, J.P.; Verloop, J.W.; Berkel, van W.J.H.; Gruppen, H.

    2012-01-01

    The antibrowning activity of sodium hydrogen sulfite (NaHSO3) was compared to that of other sulfur-containing compounds. Inhibition of enzymatic browning was investigated using a model browning system consisting of mushroom tyrosinase and chlorogenic acid (5-CQA). Development of brown color

  19. Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide?

    den Hartog, G.J.M.; Haenen, G.R.M.M.; Vegt, E.; van der Vijgh, W.J.F.; Bast, A.

    2002-01-01

    Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide? den Hartog GJ, Haenen GR, Vegt E, van der Vijgh WJ, Bast A. Department of Pharmacology and Toxicology, Maastricht University, The Netherlands. Hypochlorous acid (HOCl) is a bactericidal

  20. Critical gases for critical issues: CO2 technologies for oral drug delivery.

    Danan, Hana; Esposito, Pierandrea

    2014-02-01

    In recent years, CO2-based technologies have gained considerable interest in the pharmaceutical industry for their potential applications in drug formulation and drug delivery. The exploitation of peculiar properties of gases under supercritical conditions has been studied in the last 20 years with mixed results. Promising drug-delivery technologies, based on supercritical CO2, have mostly failed when facing challenges of industrial scaleability and economical viability. Nevertheless, a 'second generation' of processes, based on CO2 around and below critical point has been developed, possibly offering technology-based solutions to some of the current issues of pharmaceutical development. In this review, we highlight the most recent advancements in this field, with a particular focus on the potential of CO2-based technologies in addressing critical issues in oral delivery, and briefly discuss the future perspectives of dense CO2-assisted processes as enabling technologies in drug delivery.

  1. Induction of Cellulase by Gentiobiose and Its Sulfur-Containing Analog in Penicillium purpurogenum

    Kurasawa, Takashi; Yachi, Makoto; Suto, Manabu; Kamagata, Yoichi; Takao, Shoichi; Tomita, Fusao

    1992-01-01

    Cellulase induction by β-glucodisaccharides was investigated by using non-cellulase-induced mycelia of Penicillium purpurogenum P-26, a highly-cellulase-producing fungus. Gentiobiose induced significant amounts of cellulase compared with cellobiose when nojirimycin was added to the induction medium to inhibit extracellular β-glucosidase activity. Thiogentiobiose (6-S-β-d-glucopyranosyl-6-thio-d-glucose), a sulfur-containing analog of gentiobiose, was more effective for cellulase induction tha...

  2. Synthesis of sulfur-containing lubricant additives on the basis of fatty acid ethyl esters

    Iurii S. Bodachivskyi

    2016-12-01

    Full Text Available The study reveals an energy-, resource- and eco-friendly method for preparation of sulfur-containing lubricant additives via interaction of fatty acid ethyl esters of rapeseed oil with elemental sulfur. The structure of synthesized compounds under various reactants ratio (5–50 wt.% of sulfur, duration (30–240 min and temperature of the process (160–215°С was investigated using various analytical techniques. According to the established data, aside from addition to double bonds, the side reaction of hydrogen substitution at α-methylene groups near these bonds occurs and induces the formation of conjugated systems and chromophoric sulfur-rich derivatives. Also, we found that increase of process duration evokes growth of polysulfane chains, in contrast to the raise of temperature, which leads to the formation of sulfur-containing heterocycles and hydrogen sulfide, as a result of elimination. Influence of accelerators on sulfurization of fatty acid ethyl esters was also examined. The most effective among them are mixtures of zinc dibutyldithiocarbamate with zinc oxide or stearic acid, which soften synthesis conditions and doubly decrease duration of the high-temperature stage. In addition, sulfur-containing compositions of ethyl esters and α-olefins, vulcanized esters by benzoyl peroxide, nonylphenols and zinc dinonylphenyldithiophosphate were designed. The study identified that lithium lubricant with sulfurized vulcanized esters provides improved tribological properties, in comparison with base lubricant or lubricant with the non-modified product.

  3. Synthesis and Studies of Sulfur-Containing Heterocyclic Molecules for Molecular Electronics

    Mazzanti, Virginia

    This work describes the synthesis and studies of sulfur containing π conjugated heterocycles, which are considered interesting motifs in the field of molecular electronics. The first project, which is covered in Chapter 1, concerns the functionalization of tetracycle dibenzo[bc,fg][1,4]dithiapent......This work describes the synthesis and studies of sulfur containing π conjugated heterocycles, which are considered interesting motifs in the field of molecular electronics. The first project, which is covered in Chapter 1, concerns the functionalization of tetracycle dibenzo[bc,fg][1......,4]dithiapentalene (DDP). Attempts to prepare the S-O analog are also discussed. Chapter 2, focuses upon the studies performed on DDP and other sulfur containing π conjugated organic molecules. Organic Field Effect Transistor devices were fabricated and their performances were evaluated. Chapter 3 entails...... the synthesis of dimeric structures of redox active system tetrathiafulvalene (TTF). Molecules with different conjugation pathways bridging two TTFs were synthesized and studied using CV and DPV in order to probe the electronic interaction between these two redox units. The last aspect of this thesis, which...

  4. Synthesis and Odor Evaluation of Five New Sulfur-Containing Ester Flavor Compounds from 4-Ethyloctanoic Acid

    Baoguo Sun

    2010-07-01

    Full Text Available Five sulfur-containing flavor compounds were synthesized for the first time by the reaction of 4-ethyloctanoyl chloride with sulfur-containing alcohols or mercaptans. The synthesized compounds are 3-(methylthiopropyl 4-ethyloctanoate, 2-methyl-3-tetrahydro-furanthiol 4-ethyloctanoate, 4-methyl-5-thiazoleethanol 4-ethyloctanoate, 2-furan-methanethiol 4-ethyloctanoate and 2-methyl-3-furanthiol 4-ethyloctanoate. These five synthetic sulfur-containing ester flavor compounds all have meaty odor and might be used in foods if approved for this purpose in the future.

  5. Synthesis and odor evaluation of five new sulfur-containing ester flavor compounds from 4-ethyloctanoic acid.

    Liu, Yuping; Chen, Haitao; Yin, Decai; Sun, Baoguo

    2010-07-29

    Five sulfur-containing flavor compounds were synthesized for the first time by the reaction of 4-ethyloctanoyl chloride with sulfur-containing alcohols or mercaptans. The synthesized compounds are 3-(methylthio)propyl 4-ethyloctanoate, 2-methyl-3-tetrahydro-furanthiol 4-ethyloctanoate, 4-methyl-5-thiazoleethanol 4-ethyloctanoate, 2-furan-methanethiol 4-ethyloctanoate and 2-methyl-3-furanthiol 4-ethyloctanoate. These five synthetic sulfur-containing ester flavor compounds all have meaty odor and might be used in foods if approved for this purpose in the future.

  6. Method of burning sulfur-containing fuels in a fluidized bed boiler

    Jones, Brian C.

    1982-01-01

    A method of burning a sulfur-containing fuel in a fluidized bed of sulfur oxide sorbent wherein the overall utilization of sulfur oxide sorbent is increased by comminuting the bed drain solids to a smaller average particle size, preferably on the order of 50 microns, and reinjecting the comminuted bed drain solids into the bed. In comminuting the bed drain solids, particles of spent sulfur sorbent contained therein are fractured thereby exposing unreacted sorbent surface. Upon reinjecting the comminuted bed drain solids into the bed, the newly-exposed unreacted sorbent surface is available for sulfur oxide sorption, thereby increasing overall sorbent utilization.

  7. A batch assay to measure microbial hydrogen sulfide production from sulfur-containing solid wastes

    Sun, Mei; Sun, Wenjie; Barlaz, Morton A.

    2016-01-01

    Large volumes of sulfur-containing wastes enter municipal solid waste landfills each year. Under the anaerobic conditions that prevail in landfills, oxidized forms of sulfur, primarily sulfate, are converted to sulfide. Hydrogen sulfide (H 2 S) is corrosive to landfill gas collection and treatment systems, and its presence in landfill gas often necessitates the installation of expensive removal systems. For landfill operators to understand the cost of managing sulfur-containing wastes, an estimate of the H 2 S production potential is needed. The objective of this study was to develop and demonstrate a biochemical sulfide potential (BSP) test to measure the amount of H 2 S produced by different types of sulfur-containing wastes in a relatively fast (30 days) and inexpensive (125 mL serum bottles) batch assay. This study confirmed the toxic effect of H 2 S on both sulfate reduction and methane production in batch systems, and demonstrated that removing accumulated H 2 S by base adsorption was effective for mitigating inhibition. H 2 S production potentials of coal combustion fly ash, flue gas desulfurization residual, municipal solid waste combustion ash, and construction and demolition waste were determined in BSP assays. After 30 days of incubation, most of the sulfate in the wastes was converted to gaseous or aqueous phase sulfide, with BSPs ranging from 0.8 to 58.8 mL H 2 S/g waste, depending on the chemical composition of the samples. Selected samples contained solid phase sulfide which contributed to the measured H 2 S yield. A 60 day incubation in selected samples resulted in 39–86% additional sulfide production. H 2 S production measured in BSP assays was compared with that measured in simulated landfill reactors and that calculated from chemical analyses. H 2 S production in BSP assays and in reactors was lower than the stoichiometric values calculated from chemical composition for all wastes tested, demonstrating the importance of assays to estimate the

  8. A batch assay to measure microbial hydrogen sulfide production from sulfur-containing solid wastes

    Sun, Mei, E-mail: msun8@uncc.edu [Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Campus Box 7908, Raleigh, NC (United States); Sun, Wenjie, E-mail: wsun@smu.edu [Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Campus Box 7908, Raleigh, NC (United States); Department of Civil and Environmental Engineering, Southern Methodist University, PO Box 750340, Dallas, TX (United States); Barlaz, Morton A., E-mail: barlaz@ncsu.edu [Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Campus Box 7908, Raleigh, NC (United States)

    2016-05-01

    Large volumes of sulfur-containing wastes enter municipal solid waste landfills each year. Under the anaerobic conditions that prevail in landfills, oxidized forms of sulfur, primarily sulfate, are converted to sulfide. Hydrogen sulfide (H{sub 2}S) is corrosive to landfill gas collection and treatment systems, and its presence in landfill gas often necessitates the installation of expensive removal systems. For landfill operators to understand the cost of managing sulfur-containing wastes, an estimate of the H{sub 2}S production potential is needed. The objective of this study was to develop and demonstrate a biochemical sulfide potential (BSP) test to measure the amount of H{sub 2}S produced by different types of sulfur-containing wastes in a relatively fast (30 days) and inexpensive (125 mL serum bottles) batch assay. This study confirmed the toxic effect of H{sub 2}S on both sulfate reduction and methane production in batch systems, and demonstrated that removing accumulated H{sub 2}S by base adsorption was effective for mitigating inhibition. H{sub 2}S production potentials of coal combustion fly ash, flue gas desulfurization residual, municipal solid waste combustion ash, and construction and demolition waste were determined in BSP assays. After 30 days of incubation, most of the sulfate in the wastes was converted to gaseous or aqueous phase sulfide, with BSPs ranging from 0.8 to 58.8 mL H{sub 2}S/g waste, depending on the chemical composition of the samples. Selected samples contained solid phase sulfide which contributed to the measured H{sub 2}S yield. A 60 day incubation in selected samples resulted in 39–86% additional sulfide production. H{sub 2}S production measured in BSP assays was compared with that measured in simulated landfill reactors and that calculated from chemical analyses. H{sub 2}S production in BSP assays and in reactors was lower than the stoichiometric values calculated from chemical composition for all wastes tested, demonstrating

  9. Structural analysis and taste evaluation of γ-glutamyl peptides comprising sulfur-containing amino acids.

    Amino, Yusuke; Wakabayashi, Hidehiko; Akashi, Satoko; Ishiwatari, Yutaka

    2018-03-01

    The structures, flavor-modifying effects, and CaSR activities of γ-glutamyl peptides comprising sulfur-containing amino acids were investigated. The chemical structures, including the linkage mode of the N-terminal glutamic acid, of γ-L-glutamyl-S-(2-propenyl)-L-cysteine (γ-L-glutamyl-S-allyl-L-cysteine) and its sulfoxide isolated from garlic were established by comparing their NMR spectra with those of authentic peptides prepared using chemical methods. Mass spectrometric analysis also enabled determination of the linkage modes in the glutamyl dipeptides by their characteristic fragmentation. In sensory evaluation, these peptides exhibited flavor-modifying effects (continuity) in umami solutions less pronounced but similar to that of glutathione. Furthermore, the peptides exhibited intrinsic flavor due to the sulfur-containing structure, which may be partially responsible for their flavor-modifying effects. In CaSR assays, γ-L-glutamyl-S-methyl-L-cysteinylglycine was most active, which indicates that the presence of a medium-sized aliphatic substituent at the second amino acid residue in γ-glutamyl peptides enhances CaSR activity.

  10. Restraint stress in lactating mice alters the levels of sulfur-containing amino acids in milk.

    Nishigawa, Takuma; Nagamachi, Satsuki; Ikeda, Hiromi; Chowdhury, Vishwajit S; Furuse, Mitsuhiro

    2018-03-30

    It is well known that maternal stress during the gestation and lactation periods induces abnormal behavior in the offspring and causes a lowering of the offspring's body weight. Various causes of maternal stress during the lactation period, relating to, for example, maternal nutritional status and reduced maternal care, have been considered. However, little is known about the effects on milk of maternal stress during the lactation period. The current study aimed to determine whether free amino acids, with special reference to sulfur-containing amino acids in milk, are altered by restraint stress in lactating mice. The dams in the stress group were restrained for 30 min at postnatal days 2, 4, 6, 8, 10 and 12. Restraint stress caused a reduction in the body weight of lactating mice. The concentration of taurine and cystathionine in milk was significantly higher in the stress group, though stress did not alter their concentration in maternal plasma. The ratio of taurine concentration in milk to its concentration in maternal plasma was significantly higher in the stress group, suggesting that stress promoted taurine transportation into milk. Furthermore, taurine concentration in milk was positively correlated with corticosterone levels in plasma. In conclusion, restraint stress in lactating mice caused the changes in the metabolism and in the transportation of sulfur-containing amino acids and resulted in higher taurine concentration in milk. Taurine concentration in milk could also be a good parameter for determining stress status in dams.

  11. Developing an energy efficient steam reforming process to produce hydrogen from sulfur-containing fuels

    Simson, Amanda

    Hydrogen powered fuel cells have the potential to produce electricity with higher efficiency and lower emissions than conventional combustion technology. In order to realize the benefits of a hydrogen fuel cell an efficient method to produce hydrogen is needed. Currently, over 90% of hydrogen is produced from the steam reforming of natural gas. However, for many applications including fuel cell vehicles, the use of a liquid fuel rather than natural gas is desirable. This work investigates the feasibility of producing hydrogen efficiently by steam reforming E85 (85% ethanol/15% gasoline), a commercially available sulfur-containing transportation fuel. A Rh-Pt/SiO2-ZrO2 catalyst has demonstrated good activity for the E85 steam reforming reaction. An industrial steam reforming process is often run less efficiently, with more water and at higher temperatures, in order to prevent catalyst deactivation. Therefore, it is desirable to develop a process that can operate without catalyst deactivation at more energy efficient conditions. In this study, the steam reforming of a sulfur-containing fuel (E85) was studied at near stoichiometric steam/carbon ratios and at 650C, conditions at which catalyst deactivation is normally measured. At these conditions the catalyst was found to be stable steam reforming a sulfur-free E85. However, the addition of low concentrations of sulfur significantly deactivated the catalyst. The presence of sulfur in the fuel caused catalyst deactivation by promoting ethylene which generates surface carbon species (coke) that mask catalytic sites. The amount of coke increased during time on stream and became increasingly graphitic. However, the deactivation due to both sulfur adsorption and coke formation was reversible with air treatment at 650°C. However, regenerations were found to reduce the catalyst life. Air regenerations produce exotherms on the catalyst surface that cause structural changes to the catalyst. During regenerations the

  12. Biotransformation of nitrogen- and sulfur-containing pollutants during coking wastewater treatment: Correspondence of performance to microbial community functional structure.

    Joshi, Dev Raj; Zhang, Yu; Gao, Yinxin; Liu, Yuan; Yang, Min

    2017-09-15

    Although coking wastewater is generally considered to contain high concentration of nitrogen- and sulfur-containing pollutants, the biotransformation processes of these compounds have not been well understood. Herein, a high throughput functional gene array (GeoChip 5.0) in combination with Illumina MiSeq sequencing of the 16S rRNA gene were used to identify microbial functional traits and their role in biotransformation of nitrogen- and sulfur-containing compounds in a bench-scale aerobic coking wastewater treatment system operated for 488 days. Biotransformation of nitrogen and sulfur-containing pollutants deteriorated when pH of the bioreactor was increased to >8.0, and the microbial community functional structure was significantly associated with pH (Mantels test, P functional microbial community structure (P functional genes for biotransformation of nitrogen- and sulfur-containing pollutants. Functional characterization of taxa and network analysis suggested that Burkholderiales, Actinomycetales, Rhizobiales, Pseudomonadales, and Hydrogenophiliales (Thiobacillus) were key functional taxa. Variance partitioning analysis showed that pH and influent ammonia nitrogen jointly explained 25.9% and 35.5% of variation in organic pollutant degrading genes and microbial community structure, respectively. This study revealed a linkage between microbial community functional structure and the likely biotransformation of nitrogen- and sulfur-containing pollutants, along with a suitable range of pH (7.0-7.5) for stability of the biological system treating coking wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Chemical protection of bacteria and cultured mammalian cells by sulfur--containing compounds

    Antoku, S [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

    1975-03-01

    Protection by sulfur-containing compounds was studied using bacteria E. coli Bsub(H) and cultured mouse leukemic cells, L 5178 Y. The protective mechanisms are discussed. The dose reduction factors of non-sulfhydryl compounds observed in the bacteria were the same as those observed in mammalian cells, and the protective activity of these compounds was proportional to their reaction rates with hydroxyl radicals. On the other hand, sulfhydryl compounds, with the exception of glutathione, offered a much greater protection than was anticipated from their radical scavenging activity. From studies under anoxia, the protection of cysteine was explained by its OH scavenging and competition with oxygen. In addition, for MEA, protection against the direct action of radiation was suggested. This was supported by the significant protection in the frozen state.

  14. Combinatorial synthesis by nature: volatile organic sulfur-containing constituents of Ruta chalepensis L.

    Escher, Sina; Niclass, Yvan; van de Waal, Matthijs; Starkenmann, Christian

    2006-09-01

    Ongoing interest in discovering new natural fragrance and flavor ingredients prompted us to examine a solvent extract of sulfurous-sweaty smelling Ruta chalepensis L. (Rutaceae) plant material more closely. Twenty-one sulfur-containing constituents of similar structures were identified by GC/MS techniques. Amongst them, 14 have never been described to occur in nature. The compounds 1-18 belong to a family of natural flavor and fragrance molecules having a 1,3-positioned O,S moiety in common. The identities of the natural constituents were confirmed by comparison with synthetic reference samples, and the organoleptic properties of the latter were studied. The relative and absolute configurations of the four stereoisomers of 4-methyl-3-sulfanylhexan-1-ol (5) were established by stereoselective synthesis. The natural isomers consisted of a 65 : 35 mixture of (3R,4S)-5 and (3S,4S)-5.

  15. Characterizing the biotransformation of sulfur-containing wastes in simulated landfill reactors.

    Sun, Wenjie; Sun, Mei; Barlaz, Morton A

    2016-07-01

    Landfills that accept municipal solid waste (MSW) in the U.S. may also accept a number of sulfur-containing wastes including residues from coal or MSW combustion, and construction and demolition (C&D) waste. Under anaerobic conditions that dominate landfills, microbially mediated processes can convert sulfate to hydrogen sulfide (H2S). The presence of H2S in landfill gas is problematic for several reasons including its low odor threshold, human toxicity, and corrosive nature. The objective of this study was to develop and demonstrate a laboratory-scale reactor method to measure the H2S production potential of a range of sulfur-containing wastes. The H2S production potential was measured in 8-L reactors that were filled with a mixture of the target waste, newsprint as a source of organic carbon required for microbial sulfate reduction, and leachate from decomposed residential MSW as an inoculum. Reactors were operated with and without N2 sparging through the reactors, which was designed to reduce H2S accumulation and toxicity. Both H2S and CH4 yields were consistently higher in reactors that were sparged with N2 although the magnitude of the effect varied. The laboratory-measured first order decay rate constants for H2S and CH4 production were used to estimate constants that were applicable in landfills. The estimated constants ranged from 0.11yr(-1) for C&D fines to 0.38yr(-1) for a mixed fly ash and bottom ash from MSW combustion. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Pore structure modification of cement concretes by impregnation with sulfur-containing compounds

    YANAKHMETOV Marat Rafisovich

    2015-02-01

    Full Text Available The authors study how the impregnation with sulfur-containing compounds changes the concrete pore structure and how it influences on the water absorption and watertightness. The results of this research indicate that impregnation of cement concrete with water-based solution of polysulphide modifies pore structure of cement concrete in such a way that it decreases total and effective porosity, reduces water absorption and increases watertightness. The proposed impregnation based on mineral helps to protect for a long time the most vulnerable parts of buildings – basements, foundations, as well as places on the facades of buildings exposed to rain, snow and groundwater. Application of the new product in the construction industry can increase the durability of materials, preventing the destruction processes caused by weathering, remove excess moisture in damp basements. The surfaces treated by protective compounds acquire antisoiling properties for a long time, and due to reduced thermal conductivity the cost of heating buildings is decreased. The effectiveness of the actions and the relatively low cost of proposed hydrophobizator makes it possible to spread widely the proposed protection method for building structures.

  17. Radiation-induced reductive modifications of sulfur-containing amino acids within peptides and proteins.

    Chatgilialoglu, Chryssostomos; Ferreri, Carla; Torreggiani, Armida; Salzano, Anna Maria; Renzone, Giovanni; Scaloni, Andrea

    2011-10-19

    The complex scenario of radical stress reactions affecting peptides/proteins can be better elucidated through the design of biomimetic studies simulating the consequences of the different free radicals attacking amino acids. In this context, ionizing radiations allowed to examine the specific damages caused by H-atoms and electrons coupled with protons, thus establishing the molecular basis of reductive radical stress. This is an innovative concept that complements the well-known oxidative stress also in view of a complete understanding of the global consequences of radical species reactivities on living systems. This review summarizes the knowledge of the chemical changes present in sulfur-containing amino acids occurring in polypeptides under reductive radical conditions, in particular the transformation of Met and Cys residues into α-amino butyric acid and alanine, respectively. Reductive radical stress causing a desulfurization process, is therefore coupled with the formation of S-centered radicals, which in turn can diffuse apart and become responsible of the damage transfer from proteins to lipids. These reductive modifications assayed in different peptide/protein sequences constitute an integration of the molecular inventories that up to now take into account only oxidative transformations. They can be useful to achieve an integrated vision of the free radical reactivities in a multifunctional system and, overall, for wider applications in the redox proteomics field. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Quantitative trait loci controlling sulfur containing amino acids, methionine and cysteine, in soybean seeds.

    Panthee, D R; Pantalone, V R; Sams, C E; Saxton, A M; West, D R; Orf, J H; Killam, A S

    2006-02-01

    Soybean [Glycine max (L.) Merr.] is the single largest source of protein in animal feed. However, a major limitation of soy proteins is their deficiency in sulfur-containing amino acids, methionine (Met) and cysteine (Cys). The objective of this study was to identify quantitative trait loci (QTL) associated with Met and Cys concentration in soybean seed. To achieve this objective, 101 F(6)-derived recombinant inbred lines (RIL) from a population developed from a cross of N87-984-16 x TN93-99 were used. Ground soybean seed samples were analyzed for Met and Cys concentration using a near infrared spectroscopy instrument. Data were analyzed using SAS software and QTL Cartographer. RIL differed (Pseed dry weight) for Cys and 4.4-8.8 (g kg(-1) seed dry weight) for Met. Heritability estimates on an entry mean basis were 0.14 and 0.57 for Cys and Met, respectively. A total of 94 polymorphic simple sequence repeat molecular genetic markers were screened in the RIL. Single factor ANOVA was used to identify candidate QTL, which were confirmed by composite interval mapping using QTL Cartographer. Four QTL linked to molecular markers Satt235, Satt252, Satt427 and Satt436 distributed on three molecular linkage groups (MLG) D1a, F and G were associated with Cys and three QTL linked to molecular markers Satt252, Satt564 and Satt590 distributed on MLG F, G and M were associated with Met concentration in soybean seed. QTL associated with Met and Cys in soybean seed will provide important information to breeders targeting improvements in the nutritional quality of soybean.

  19. Comparative study of reactions between µ-nitrido- or µ-oxo-bridged iron tetrasulfophthalocyanines and sulfur-containing reductants

    Dereven’kov Ilia A.

    2013-01-01

    Full Text Available A comparative study of reactivity of μ-nitrido- and μ-oxo-dimers of iron tetrasulfophthalocyanine has been performed in aqueous solutions of various acidity. The substantially higher stability of nitrido-bridged structure under both strongly acidic and strongly alkaline environments was demonstrated. Reactions of the complexes with sulfur-containing reductants (sodium dithionite, thiourea dioxide, sodium hydroxymethanesulfinate, L-cysteine has been studied. Differences in reduction processes were explained.

  20. Thermally induced degradation of sulfur-containing aliphatic glucosinolates in broccoli sprouts (Brassica oleracea var. italica) and model systems.

    Hanschen, Franziska S; Platz, Stefanie; Mewis, Inga; Schreiner, Monika; Rohn, Sascha; Kroh, Lothar W

    2012-03-07

    Processing reduces the glucosinolate (GSL) content of plant food, among other aspects due to thermally induced degradation. Since there is little information about the thermal stability of GSL and formation of corresponding breakdown products, the thermally induced degradation of sulfur-containing aliphatic GSL was studied in broccoli sprouts and with isolated GSL in dry medium at different temperatures as well as in aqueous medium at different pH values. Desulfo-GSL have been analyzed with HPLC-DAD, while breakdown products were estimated using GC-FID. Whereas in the broccoli sprouts structural differences of the GSL with regard to thermal stability exist, the various isolated sulfur-containing aliphatic GSL degraded nearly equally and were in general more stable. In broccoli sprouts, methylsulfanylalkyl GSL were more susceptible to degradation at high temperatures, whereas methylsulfinylalkyl GSL were revealed to be more affected in aqueous medium under alkaline conditions. Besides small amounts of isothiocyanates, the main thermally induced breakdown products of sulfur-containing aliphatic GSL were nitriles. Although they were most rapidly formed at comparatively high temperatures under dry heat conditions, their highest concentrations were found after cooking in acidic medium, conditions being typical for domestic processing.

  1. Particulate sulfur-containing lipids: Production and cycling from the epipelagic to the abyssopelagic zone

    Gašparović, Blaženka; Penezić, Abra; Frka, Sanja; Kazazić, Saša; Lampitt, Richard S.; Holguin, F. Omar; Sudasinghe, Nilusha; Schaub, Tanner

    2018-04-01

    There are major gaps in our understanding of the distribution and role of lipids in the open ocean especially with regard to sulfur-containing lipids (S-lipids). Here, we employ a powerful analytical approach based on high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to elucidate depth-related S-lipid production and molecular transformations in suspended particulate matter from the Northeast Atlantic Ocean in this depth range. We show that within the open-ocean environment S-lipids contribute up to 4.2% of the particulate organic carbon, and that up to 95% of these compounds have elemental compositions that do not match those found in the Nature Lipidomics Gateway database (termed "novel"). Among the remaining 5% of lipids that match the database, we find that sulphoquinovosyldiacylglycerol (SQDG) are efficiently removed while sinking through the mesopelagic zone. The relative abundance of other assigned lipids (sulphoquinovosylmonoacylglycerol (SQMG), sulfite and sulfate lipids, Vitamin D2 and D3 derivatives, and sphingolipids) did not change substantially with depth. The novel S-lipids, represented by hundreds of distinct elemental compositions (160-300 molecules at any one depth), contribute increasingly to the lipid and particulate organic matter pools with increased depth. Depth-related transformations cause (i) incomplete degradation/transformation of unsaturated S-lipids which leads to the depth-related accumulation of the refractory saturated compounds with reduced molecular weight (average 455 Da) and (ii) formation of highly unsaturated S-lipids (average abyssopelagic molecular double bond equivalents, DBE=7.8) with lower molecular weight (average 567 Da) than surface S-lipids (average 592 Da). A depth-related increase in molecular oxygen content is observed for all novel S-lipids and indicates that oxidation has a significant role in their transformation while (bio)hydrogenation possibly impacts the formation of

  2. Adsorption behavior of sulfur-containing amino acid molecule on transition metal surface studied by S K-edge NEXAFS

    Yagi, S.; Matsumura, K.; Nakano, Y.; Ikenaga, E.; Sardar, S.A.; Syed, J.A.; Soda, K.; Hashimoto, E.; Tanaka, K.; Taniguchi, M.

    2003-01-01

    Adsorption behavior of a sulfur-containing amino acid L-cysteine molecule on transition metal surface have been investigated by S K-edge near-edge X-ray absorption fine structure. The L-cysteine molecule for first adsorption layer was found to dissociate on polycrystalline nickel surface, whereas molecularly adsorbed on copper surface at room temperature. Most of the L-cysteine molecules have been dissociated on nickel surface in annealing condition up to 353 K. On the other hand, the L-cysteine molecule did not dissociate on copper surface and the elongation of the S-C bonding occurred at 353 K

  3. UV absorption cross-sections of selected sulfur-containing compounds at temperatures up to 500°C

    Grosch, Helge; Fateev, Alexander; Clausen, Sønnik

    2015-01-01

    The temperature dependence of the ultraviolet absorption cross-sections of three different sulfur containing compounds, hydrogen sulfide (H2S), carbon disulfide (CS2) and carbonyl sulfide (OCS), are presented between 200nm and 360nm at a resolution of 0.018nm. The absorption cross-sections for each...... compound are initially compared with those available in the literature, followed by the discussion of the measurements and their spectral features at three temperatures up to 500°C/773K. Uncertainties in the measured absorption cross-sections are also addressed....

  4. Synthesis of Hydrophilic Sulfur-Containing Adsorbents for Noble Metals Having Thiocarbonyl Group Based on a Methacrylate Bearing Dithiocarbonate Moieties

    Haruki Kinemuchi

    2018-01-01

    Full Text Available Novel hydrophilic sulfur-containing adsorbents for noble metals were prepared by the radical terpolymerization of a methacrylate bearing dithiocarbonate moieties (DTCMMA, hydrophilic monomers, and a cross-linker. The resulting adsorbents efficiently and selectively adsorbed noble metals (Au, Ag, and Pd from various multielement aqueous solutions at room temperature owing to the thiocarbonyl group having high affinity toward noble metals. The metal adsorption by the adsorbents was proceeded by simple mixing followed by filtration. The noble metal selectivity of the adsorbent obtained from DTCMMA and N-isopropylacrylamide was higher than that of the adsorbent obtained from DTCMMA and N,N-dimethylacrylamide due to the lower nonspecific adsorption.

  5. Comparison between female and male of demand of sulfur-containing amino acid of domestic silk worms

    Shinbo, Hiroshi; Inokuchi, Tamio

    1977-01-01

    Comparison of the demand of sulfur-containing amino acid (methionine and cystine) of young domestic silk worms was made between female and male using amino acid diet, and the relation among growth, blood protein and ninhydrin positive substance concentration was discussed. When 3 mg/g of methionine was added to the diet, the growth promotion effect of cystine was hardly recognized for male, while no addition of cystine showed inferior growth for female, however the normal growth was recognized when more than 1 mg/g was added. Accordingly, it is recognized that the female requires more sulfur-containing amino acid than the male. The relationship between the addition of methionine and cystine and the blood protein concentration showed the tendency to conform to the growth approximately. In the effects of blood protein concentration due to diet condition, the difference between female and male were recognized. The relationship between the addition of methionine and cystine in the diet and the ninhydrin positive substance concentration was high in case of the lack of methionine, but the relationship to cystine addition and the difference between female and male were not clear. As a result of measuring 14 CO 2 exhaled from the young worms injected with DL-cystine-1- 14 C, the resolution of cystine in the living body of female was lower than that of male. (Iwakiri, K.)

  6. Toxicity of nickel and silver to Nostoc muscorum: interaction with ascorbic acid, glutathione, and sulfur-containing amino acids.

    Rai, L C; Raizada, M

    1987-08-01

    Exposure of Nostoc muscorum to different concentrations of Ni and Ag brought about reduction in growth, carbon fixation, heterocyst production, and nitrogenase activity and increase in the loss of ions (K+, Na+). In an attempt to ameliorate the toxicity of test metals by ascorbic acid, glutathione, and sulfur-containing amino acids (L-cysteine and L-methionine), it was found that the level of protection by ascorbic acid and glutathione was more for Ag than Ni. However, metal-induced inhibition of growth and carbon fixation was equally ameliorated by methionine. But the level of protection by cysteine was quite different, i.e., 27% for Ni and 22% for Ag. Protection of metal toxicity in N. muscorum by amino acids lends further support to self-detoxifying ability of cyanobacteria because they are known to synthesize all essential amino acids.

  7. Antiinflammatory and neurological activity of pyrithione and related sulfur-containing pyridine N-oxides from Persian shallot (Allium stipitatum)

    Krejčová, Petra; Kučerová, Petra; Stafford, Gary Ivan

    2014-01-01

    ETHNOPHARMACOLOGICAL RELEVANCE: Persian shallot (Allium stipitatum) is a bulbous plant native to Turkey, Iran and Central Asia. It is frequently used in folk medicine for the treatment of a variety of disorders, including inflammation and stress. Antiinflammatory and neurological activities...... of pyrithione and four related sulfur-containing pyridine N-oxides which are prominent constituents of Allium stipitatum were tested. METHODS: The antiinflammatory activity was tested by the ability of the compounds to inhibit cyclooxygenase (COX-1 and COX-2), whereas the neurological activities were evaluated...... by assessing the compounds ability to inhibit monoamine oxidase-A (MAO-A) and acetylcholinesterase (AChE). The compounds׳ affinity for the serotonin transport protein (SERT) and the GABAA-benzodiazepine receptor were also investigated. RESULTS: 2-[(Methylthio)methyldithio]pyridine N-oxide showed very high...

  8. The Quantitation of Sulfur Mustard By-Products, Sulfur-Containing Herbicides, and Organophosphonates in Soil and Concrete

    Tomkins, B.A., Sega, G.A. [Oak Ridge National Lab., TN (United States)], Macnaughton, S.J. [Microbial Insights, Inc., Rockford, TN (United States)

    1997-12-31

    Over the past fifty years, the facilities at Rocky Mountain Arsenal have been used for the manufacturing, bottling, and shipping sulfur- containing herbicides, sulfur mustard, and Sarin. There is a need for analytical methods capable of determining these constituents quickly to determine exactly how specific waste structural materials should be handled, treated, and landfilled.These species are extracted rapidly from heated samples of soil or crushed concrete using acetonitrile at elevated pressure, then analyzed using a gas chromatograph equipped with a flame photometric detector. Thiodiglycol, the major hydrolysis product of sulfur mustard, must be converted to a silylated derivative prior to quantitation. Detection limits, calculated using two statistically-unbiased protocols, ranged between 2-13 micrograms analyte/g soil or concrete.

  9. Concentration of sulfur-containing amino acids at turkey broilers during and after muscle dystrophy, fed with deficient feed supplemented with oxidised fat

    K. Stoyanchev

    2017-06-01

    Full Text Available Abstract. The aim of the present study was to reproduce experimentally muscular dystrophy in 50 broiler turkeys, through early nutrition with a diet deficient in vitamin E, selenium and sulfur-containing amino acids, supplemented with oxidised fat and to study blood plasma sulfur containing amino acids (methionine rd and cysteine. The experiments were conducted with 1 day-old broiler turkeys. By the 3 day of life, they were divided into 40 experimental (II group and 10 control birds (I group; the latter were fed a standard compound feed, whereas the former group received a diet deficient in sulfur-containing amino acids methionine and cysteine (reduced up to 50%, vitamin E, and Se (from 0.2 mg/kg in standard feed to 0.01 mg/kg, further supplemented with oxidized fat containing peroxides and aldehydes with peroxide number of the food 8.0 meq O /kg. The clinical signs of experimental muscle dystrophy in broiler turkeys 2 th appeared first by the 25 day of feeding, when the mild clinical form (II A group and the severe clinical form (II B group werewas established. The results indicated clearly that in turkey broilers suffering from muscle dystrophy, the concentrations of sulfur-containing amino acids cysteine and methionine decreased. After the treatment of turkey broilers withmuscle dystrophy, and supplementation with non-deficient forage with Se, vitamin E, but also with sulfurcontaining amino acids cysteine ormethionine with Seled at a dosage 0.06mg/kg, the plasma levels of sulfur-containing amino acids cysteine andmethionine ® was normalized in the mild clinical form (II A group. The birds affected by the severe clinical form of disease (II B group, which were not treated with Seled and whose deficient feed was not corrected, could not recover and levels of sulfur-containing amino acids cysteine and methionine did not normalize.

  10. Identification of novel sulfur-containing steroids in sediments and petroleum: probable incorporation of sulfur into δ 5,7-sterols during early diagenesis

    Sinninghe Damsté, Jaap S.; Schouten, Stefan; de Leeuw, Jan W.; van Duin, Adri C. T.; Geenevasen, Jan A. J.

    1999-01-01

    A novel sulfur-containing sterane, 4α,7α-epithio-5β-cholestane, has been identified in a sediment extract from the Miocene Northern Apennines marl (Italy) after its isolation by column chromatography and high pressure liquid chromatography. The compound has been characterised by GC-MS and mild Nickel boride desulfurisation and one and two-dimensional 1H NMR techniques. C 27-C 29 homologs have been detected in sediment extracts of three different formations and in one petroleum sample. These sulfur-containing steroids are probably formed by an intramolecular reaction of inorganic sulfides with early diagenetic products of Δ 5,7-sterols.

  11. Harmful impact on presynaptic glutamate and GABA transport by carbon dots synthesized from sulfur-containing carbohydrate precursor.

    Borisova, Tatiana; Dekaliuk, Mariia; Pozdnyakova, Natalia; Pastukhov, Artem; Dudarenko, Marina; Borysov, Arsenii; Vari, Sandor G; Demchenko, Alexander P

    2017-07-01

    Carbon nanoparticles that may be potent air pollutants with adverse effects on human health often contain heteroatoms including sulfur. In order to study in detail their effects on different physiological and biochemical processes, artificially produced carbon dots (CDs) with well-controlled composition that allows fluorescence detection may be of great use. Having been prepared from different types of organic precursors, CDs expose different atoms at their surface suggesting a broad variation of functional groups. Recently, we demonstrated neurotoxic properties of CDs synthesized from the amino acid β-alanine, and it is of importance to analyze whether CDs obtained from different precursors and particularly those exposing sulfur atoms induce similar neurotoxic effects. This study focused on synthesis of CDs from the sulfur-containing precursor thiourea-CDs (TU-CDs) with a size less than 10 nm, their characterization, and neuroactivity assessment. Neuroactive properties of TU-CDs were analyzed based on their effects on the key characteristics of glutamatergic and γ-aminobutyric acid (GABA) neurotransmission in isolated rat brain nerve terminals. It was observed that TU-CDs (0.5-1.0 mg/ml) attenuated the initial velocity of Na + -dependent transporter-mediated uptake and accumulation of L-[ 14 C]glutamate and [ 3 H]GABA by nerve terminals in a dose-dependent manner and increased the ambient level of the neurotransmitters. Starting from the concentration of 0.2 mg/ml, TU-CDs evoked a gradual dose-dependent depolarization of the plasma membrane of nerve terminals measured with the cationic potentiometric dye rhodamine 6G. Within the concentration range of 0.1-0.5 mg/ml, TU-CDs caused an "unphysiological" step-like increase in fluorescence intensity of the рН-sensitive fluorescent dye acridine orange accumulated by synaptic vesicles. Therefore, despite different surface properties and fluorescent features of CDs prepared from different starting materials

  12. A Universal Strategy To Prepare Sulfur-Containing Polymer Composites with Desired Morphologies for Lithium-Sulfur Batteries.

    Zeng, Shao-Zhong; Zeng, Xierong; Tu, Wenxuan; Huang, Haitao; Yu, Liang; Yao, Yuechao; Jin, Nengzhi; Zhang, Qi; Zou, Jizhao

    2018-06-19

    Lithium-sulfur (Li-S) batteries are probably the most promising candidates for the next-generation batteries owing to their high energy density. However, Li-S batteries face severe technical problems where the dissolution of intermediate polysulfides is the biggest problem because it leads to the degradation of the cathode and the lithium anode, and finally the fast capacity decay. Compared with the composites of elemental sulfur and other matrices, sulfur-containing polymers (SCPs) have strong chemical bonds to sulfur and therefore show low dissolution of polysulfides. Unfortunately, most SCPs have very low electron conductivity and their morphologies can hardly be controlled, which undoubtedly depress the battery performances of SCPs. To overcome these two weaknesses of SCPs, a new strategy was developed for preparing SCP composites with enhanced conductivity and desired morphologies. With this strategy, macroporous SCP composites were successfully prepared from hierarchical porous carbon. The composites displayed discharge/charge capacities up to 1218/1139, 949/922, and 796/785 mA h g -1 at the current rates of 5, 10, and 15 C, respectively. Considering the universality of this strategy and the numerous morphologies of carbon materials, this strategy opens many opportunities for making carbon/SCP composites with novel morphologies.

  13. Greenhouse Gases

    ... Production of Hydrogen Use of Hydrogen Greenhouse Gases Basics | | Did you know? Without naturally occurring greenhouse gases, the earth would be too cold to support life as we know it. Without the greenhouse effect, ...

  14. Preparative Separation of Sulfur-Containing Diketopiperazines from Marine Fungus Cladosporium sp. Using High-Speed Counter-Current Chromatography in Stepwise Elution Mode

    Gu, Binbin; Zhang, Yanying; Ding, Lijian; He, Shan; Wu, Bin; Dong, Junde; Zhu, Peng; Chen, Juanjuan; Zhang, Jinrong; Yan, Xiaojun

    2015-01-01

    High-speed counter-current chromatography (HSCCC) was successively applied to the separation of three sulfur-containing diketopiperazines (DKPs) (including two new compounds cladosporin A (1) and cladosporin B (3), and a known compound haematocin (2)) from a marine fungus Cladosporium sp. The two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v) and (2:1:2:1, v/v), in stepwise elution mode, was used for HSCCC. The preparative HSCCC separation was perfor...

  15. Comparison of comprehensive two-dimensional gas chromatography coupled with sulfur-chemiluminescence detector to standard methods for speciation of sulfur-containing compounds in middle distillates.

    Ruiz-Guerrero, Rosario; Vendeuvre, Colombe; Thiébaut, Didier; Bertoncini, Fabrice; Espinat, Didier

    2006-10-01

    The monitoring of total sulfur content and speciation of individual sulfur-containing compounds in middle distillates is required for efficient catalyst selection and for a better understanding of the kinetics of the reactions involved in hydrotreament processes. Owing to higher resolution power and enhanced sensitivity, comprehensive two-dimensional gas chromatography (GCxGC) hyphenated to sulfur chemiluminescence detection (SCD) has recently evolved as a powerful tool for improving characterization and identification of sulfur compounds. The aim of this paper is to compare quantitatively GCxGC-SCD and various other methods commonly employed in the petroleum industry, such as X-ray fluorescence, conventional GC-SCD, and high-resolution mass spectrometry, for total sulfur content determination and speciation analysis. Different samples of middle distillates have been analyzed to demonstrate the high potential and important advantages of GCxGC-SCD for innovative and quantitative analysis of sulfur-containing compounds. More accurate and detailed results for benzothiophenes and dibenzothiophenes are presented, showing that GCxGC-SCD should become, in the future, an essential tool for sulfur speciation analysis.

  16. Preparative separation of sulfur-containing diketopiperazines from marine fungus Cladosporium sp. using high-speed counter-current chromatography in stepwise elution mode.

    Gu, Binbin; Zhang, Yanying; Ding, Lijian; He, Shan; Wu, Bin; Dong, Junde; Zhu, Peng; Chen, Juanjuan; Zhang, Jinrong; Yan, Xiaojun

    2015-01-09

    High-speed counter-current chromatography (HSCCC) was successively applied to the separation of three sulfur-containing diketopiperazines (DKPs) (including two new compounds cladosporin A (1) and cladosporin B (3), and a known compound haematocin (2)) from a marine fungus Cladosporium sp. The two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v) and (2:1:2:1, v/v), in stepwise elution mode, was used for HSCCC. The preparative HSCCC separation was performed on 300 mg of crude sample yielding 26.7 mg of compound 3 at a purity of over 95%, 53.6 mg of a mixture of compounds 1 and 2, which was further separated by preparative-HPLC yielding 14.3 mg of compound 1 and 25.4 mg of compound 2 each at a purity of over 95%. Their structures were established by spectroscopic methods. The sulfur-containing DKPs suppressed the proliferation of hepatocellular carcinoma cell line HepG2. The present work represents the first application of HSCCC in the efficient preparation of marine fungal natural products.

  17. Preparative Separation of Sulfur-Containing Diketopiperazines from Marine Fungus Cladosporium sp. Using High-Speed Counter-Current Chromatography in Stepwise Elution Mode

    Binbin Gu

    2015-01-01

    Full Text Available High-speed counter-current chromatography (HSCCC was successively applied to the separation of three sulfur-containing diketopiperazines (DKPs (including two new compounds cladosporin A (1 and cladosporin B (3, and a known compound haematocin (2 from a marine fungus Cladosporium sp. The two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v and (2:1:2:1, v/v, in stepwise elution mode, was used for HSCCC. The preparative HSCCC separation was performed on 300 mg of crude sample yielding 26.7 mg of compound 3 at a purity of over 95%, 53.6 mg of a mixture of compounds 1 and 2, which was further separated by preparative-HPLC yielding 14.3 mg of compound 1 and 25.4 mg of compound 2 each at a purity of over 95%. Their structures were established by spectroscopic methods. The sulfur-containing DKPs suppressed the proliferation of hepatocellular carcinoma cell line HepG2. The present work represents the first application of HSCCC in the efficient preparation of marine fungal natural products.

  18. Electronegative gases

    Christophorou, L.G.

    1981-01-01

    Recent knowledge on electronegative gases essential for the effective control of the number densities of free electrons in electrically stressed gases is highlighted. This knowledge aided the discovery of new gas dielectrics and the tailoring of gas dielectric mixtures. The role of electron attachment in the choice of unitary gas dielectrics or electronegative components in dielectric gas mixtures, and the role of electron scattering at low energies in the choice of buffer gases for such mixtures is outlined

  19. Greenhouse Gases

    ... also produced by human activities. Some, such as industrial gases, are exclusively human made. What are the types ... Carbon dioxide (CO2) Methane (CH4) Nitrous oxide (N2O) Industrial gases: Hydrofluorocarbons (HFCs) Perfluorocarbons (PFCs) Sulfur hexafluoride (SF6 Nitrogen ...

  20. Atmosphere-Ocean Coupling through Trace Gases

    Tegtmeier, S.; Atlas, E. L.; Krüger, K.; Lennartz, S. T.; Marandino, C. A.; Patra, P. K.; Quack, B.; Schlundt, C.

    2017-12-01

    Halogen- and sulfur-containing trace gases, as well as other volatile organic compounds (VOCs, such as isoprene) from biogeochemical marine sources are important constituents of the ocean and the atmosphere. These compounds exert wide-ranging influence on atmospheric chemical processes and climate interactions, as well as on human health in coastal regions. In their reactive form, they can affect the oxidizing capacity of the air and lead to the formation of new particles or the growth of existing ones. In this contribution, marine derived halogen-, sulfur-, and oxygen-containing compounds will be discussed. Their net flux into the atmosphere and their impact on atmospheric processes is analyzed based on observations and model simulations.

  1. The effect of green tea extract on the removal of sulfur-containing oral malodor volatiles in vitro and its potential application in chewing gum.

    Zeng, Q C; Wu, A Z; Pika, J

    2010-09-01

    Increasing pH solution from 7.5 to 8.0 was found to significantly improve the effectiveness of green tea extract for methanethiol removal in vitro. Green tea extract was also found to remove hydrogen sulfide and its effectiveness was greatly improved under alkaline conditions. It was found that with green tea extract, maximum H₂S removal was achieved when the pH was between 8.1 and 8.4 at 37 °C for 5 min. Further increases in pH resulted in decrease of the extract effectiveness. Vegetable acetone powders which contain polyphenol oxidases or peroxidases were found to further enhance the effectiveness for the removal of thiols when used in combination with green tea extracts at body temperature under alkaline conditions. Adding 5% baking soda to green tea extract-containing chewing gum was found to buffer saliva pHs to 8.0 during 10 min of chewing. However, severe discoloration was observed and undesirable bitterness was perceived, most likely due to the polymerization of unencapsulated green tea polyphenols. Therefore, encapsulation of green tea extract is recommended for applications at elevated pHs.

  2. Irritant gases

    Meulenbelt, J

    Acute inhalation injury can result from the use of household cleaning agents (e.g. chlorine, ammonia), industrial or combustion gases (e.g. sulfur dioxide, nitrogen oxides) or bioterrorism. The severity of the injury is to a great extent determined by the circumstances of exposure. If exposure was

  3. Dietary Sulfur-Containing Amino Acids Are Associated with Higher Prevalence of Overweight/Obesity in Northern Chinese Adults, an Internet-Based Cross-Sectional Study.

    Li, Yan-Chuan; Li, Yu-Zheng; Li, Rui; Lan, Li; Li, Chun-Long; Huang, Min; Shi, Dan; Feng, Ren-Nan; Sun, Chang-Hao

    2018-06-07

    Elevation of plasma sulfur-containing amino acids (SAAs) is generally associated with higher body mass index (BMI) and unfavorable lipid profiles. It is not known how dietary SAAs relate to these associations in humans. A convenient tool named internet-based dietary questionnaire for Chinese (IDQC) was used to estimate dietary SAAs intake. A total of 936 participants were randomly recruited and asked to complete the IDQC. Furthermore, 90 subjects were randomly selected to perform a subgroup study. The associations between dietary SAAs and prevalence of obesity, lipid profiles, and status of insulin resistance (IR), inflammation and oxidative stress were assessed. Dietary total SAAs and cysteine of overweight/obese participants were significantly higher. Dietary total SAAs and cysteine were positively associated with BMI and waist circumference. Higher dietary total SAAs were associated with higher prevalence of overweight/obesity. Higher dietary total SAAs and cysteine also associated with higher serum triglyceride (total cholesterol), low density lipoprotein, fasting blood glucose, 2 h-postprandial glucose, and homeostasis model assessment of IR. In the subgroup study, positive associations between dietary SAAs and inflammation biomarkers were also observed. Dietary SAAs are associated with higher prevalence of overweight/obesity, unfavorable lipid profiles and status of IR, and inflammation. © 2018 S. Karger AG, Basel.

  4. Prebiotic Synthesis of Methionine and Other Sulfur-Containing Organic Compounds on the Primitive Earth: A Contemporary Reassessment Based on an Unpublished 1958 Stanley Miller Experiment

    Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, Jason P.; Glavin, Daniel P.; Lazcano, Antonio

    2010-01-01

    Original extracts from an unpublished 1958 experiment conducted by the late Stanley L. Miller were recently found and analyzed using modern state-of-the-art analytical methods. The extracts were produced by the action of an electric discharge on a mixture of methane (CH4), hydrogen sulfide (H2S), ammonia (NH3), and carbon dioxide (CO2). Racemic methionine was farmed in significant yields, together with other sulfur-bearing organic compounds. The formation of methionine and other compounds from a model prebiotic atmosphere that contained H2S suggests that this type of synthesis is robust under reducing conditions, which may have existed either in the global primitive atmosphere or in localized volcanic environments on the early Earth. The presence of a wide array of sulfur-containing organic compounds produced by the decomposition of methionine and cysteine indicates that in addition to abiotic synthetic processes, degradation of organic compounds on the primordial Earth could have been important in diversifying the inventory of molecules of biochemical significance not readily formed from other abiotic reactions, or derived from extraterrestrial delivery.

  5. Sulfur-containing constituents and one 1H-pyrrole-2-carboxylic acid derivative from pineapple [Ananas comosus (L.) Merr.] fruit.

    Zheng, Zong-Ping; Ma, Jinyu; Cheng, Ka-Wing; Chao, Jianfei; Zhu, Qin; Chang, Raymond Chuen-Chung; Zhao, Ming; Lin, Zhi-Xiu; Wang, Mingfu

    2010-12-01

    Two sulfur-containing compounds, (S)-2-amino-5-((R)-1-carboxy-2-((E)-3-(4-hydroxy-3-methoxyphenyl)allylthio)ethyl-amino)-5-oxopentanoic acid (1) and (S)-2-amino-5-((R)-1-(carboxymethylamino)-3-((E)-3-(4-hydroxyphenyl)allylthio)-1-oxopropan-2-ylamino)-5-oxopentanoic acid (2), and one 1H-pyrrole-2-carboxylic acid derivative, 6-(3-(1H-pyrrole-2-carbonyloxy)-2-hydroxypropoxy)-3,4,5-trihydroxy-tetrahydro-2H-pyran-2-carboxylic acid (3), together with eighteen known phenolic compounds, were isolated from the fruits of pineapple. Their structures were elucidated by a combination of spectroscopic analyses. Some of these compounds showed inhibitory activities against tyrosinase. The half maximal inhibitory concentration values of compounds 1, 4, 5, 6, 7 are lower than 1 mM. These compounds may contribute to the well-known anti-browning effect of pineapple juice and be potential skin whitening agents in cosmetic applications. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Industrial gases

    Hunter, D.; Jackson, D.; Coeyman, M.

    1993-01-01

    Industrial gas companies have fought hard to boost sales and hold margins in the tough economic climate, and investments are well down from their 1989-'91 peak. But 'our industry is still very strong long term' says Alain Joly, CEO of industry leader L'Air Liquide (AL). By 1994, if a European and Japanese recovery follows through on one in the U.S., 'we could see major [investment] commitments starting again,' he says. 'Noncryogenic production technology is lowering the cost of gas-making possible new applications, oxygen is getting plenty of attention in the environmental area, and hydrogen also fits into the environmental thrust,' says Bob Lovett, executive v.p./gases and equipment with Air Products ampersand Chemicals (AP). Through the 1990's, 'Industrial gases could grow even faster than in the past decade,' he says. Virtually a new generation of new gases applications should become reality by the mid-1990s, says John Campbell, of industry consultants J.R. Campbell ampersand Associates (Lexington, MA). Big new oxygen volumes will be required for powder coal injection in blast furnaces-boosting a steel mill's requirement as much as 40% and coal gasification/combined cycle (CGCC). Increased oil refinery hydroprocessing needs promise hydrogen requirements

  7. Noble Gases

    Podosek, F. A.

    2003-12-01

    The noble gases are the group of elements - helium, neon, argon, krypton, xenon - in the rightmost column of the periodic table of the elements, those which have "filled" outermost shells of electrons (two for helium, eight for the others). This configuration of electrons results in a neutral atom that has relatively low electron affinity and relatively high ionization energy. In consequence, in most natural circumstances these elements do not form chemical compounds, whence they are called "noble." Similarly, much more so than other elements in most circumstances, they partition strongly into a gas phase (as monatomic gas), so that they are called the "noble gases" (also, "inert gases"). (It should be noted, of course, that there is a sixth noble gas, radon, but all isotopes of radon are radioactive, with maximum half-life a few days, so that radon occurs in nature only because of recent production in the U-Th decay chains. The factors that govern the distribution of radon isotopes are thus quite different from those for the five gases cited. There are interesting stories about radon, but they are very different from those about the first five noble gases, and are thus outside the scope of this chapter.)In the nuclear fires in which the elements are forged, the creation and destruction of a given nuclear species depends on its nuclear properties, not on whether it will have a filled outermost shell when things cool off and nuclei begin to gather electrons. The numerology of nuclear physics is different from that of chemistry, so that in the cosmos at large there is nothing systematically special about the abundances of the noble gases as compared to other elements. We live in a very nonrepresentative part of the cosmos, however. As is discussed elsewhere in this volume, the outstanding generalization about the geo-/cosmochemistry of the terrestrial planets is that at some point thermodynamic conditions dictated phase separation of solids from gases, and that the

  8. Novel PVC-membrane potentiometric sensors based on a recently synthesized sulfur-containing macrocyclic diamide for Cd2+ ion. Application to flow-injection potentiometry.

    Shamsipur, Mojtaba; Dezaki, Abbas Shirmardi; Akhond, Morteza; Sharghi, Hashem; Paziraee, Zahra; Alizadeh, Kamal

    2009-12-30

    A new sulfur-containing macrocyclic diamide, 1,15-diaza-3,4,12,13-dibenzo-5,11-dithia-8-oxa-1,15-(2,6-pyrido)cyclooctadecan-2,14-dione, L, was synthesized, characterized and used as an active component for fabrication of PVC-based polymeric membrane (PME), coated graphite (CGE) and coated silver wire electrodes (CWE) for sensing Cd(2+) ion. The electrodes exhibited linear Nernstian responses to Cd(2+) ion in the concentration range of 3.3 x 10(-6) to 3.3 x 10(-1)M (for PME, LOD=1.2 x 10(-6)M), 2.0 x 10(-7) to 3.3 x 10(-1)M (for CWE, LOD=1.3 x 10(-7)M) and 1.6 x 10(-8) to 1.3 x 10(-1)M (for CGE, LOD=1.0 x 10(-8)M). The CGE was used as a proper detection system in flow-injection potentiometry (FIP) with a linear Nernstian range of 3.2 x 10(-8) to 1.4 x 10(-1)M (LOD=1.3 x 10(-8)M). The optimum pH range was 3.5-7.6. The electrodes revealed fairly good discriminating ability towards Cd(2+) in comparison with a large number of alkali, alkaline earth, transition and heavy metal ions. The electrodes found to be chemically inert, showing a fast response time of <5s, and could be used practically over a period of about 2-3 months. The practical utility of the proposed system has also been reported.

  9. Comparative study of the oxidation behavior of sulfur-containing amino acids and glutathione by electrochemistry-mass spectrometry in the presence and absence of cisplatin.

    Zabel, Robert; Weber, Günther

    2016-02-01

    Small sulfur-containing compounds are involved in several important biochemical processes, including-but not limited to-redox regulation and drug conjugation/detoxification. While methods for stable redox pairs of such compounds (thiols/disulfides) are available, analytical data on more labile and short-lived redox intermediates are scarce, due to highly challenging analytical requirements. In this study, we employ the direct combination of reagentless electrochemical oxidation and mass spectrometric (EC-MS) identification for monitoring oxidation reactions of cysteine, N-acetylcysteine, methionine, and glutathione under simulated physiological conditions (pH 7.4, 37 °C). For the first time, all theoretically expected redox intermediates-with only one exception-are detected simultaneously and in situ, including sulfenic, sulfinic, and sulfonic acids, disulfides, thiosulfinates, thiosulfonates, and sulfoxides. By monitoring the time/potential-dependent interconversion of sulfur species, mechanistic oxidation routes are confirmed and new reactions detected, e.g., sulfenamide formation due to reaction with ammonia from the buffer. Furthermore, our results demonstrate a highly significant impact of cisplatin on the redox reactivity of sulfur species. Namely, the amount of thiol oxidation to sulfonic acid via sulfenic and sulfinic acid intermediates is diminished for glutathione in the presence of cisplatin in favor of the disulfide formation, while for N-acetylcysteine the contrary applies. N-acetylcysteine is the only ligand which displays enhanced oxidation currents upon cisplatin addition, accompanied by increased levels of thiosulfinate and thiosulfonate species. This is traced back to thiol reactivity and highlights the important role of sulfenic acid intermediates, which may function as a switch between different oxidation routes.

  10. Fuel gases

    Anon.

    1996-01-01

    This paper gives a brief presentation of the context, perspectives of production, specificities, and the conditions required for the development of NGV (Natural Gas for Vehicle) and LPG-f (Liquefied Petroleum Gas fuel) alternative fuels. After an historical presentation of 80 years of LPG evolution in vehicle fuels, a first part describes the economical and environmental advantages of gaseous alternative fuels (cleaner combustion, longer engines life, reduced noise pollution, greater natural gas reserves, lower political-economical petroleum dependence..). The second part gives a comparative cost and environmental evaluation between the available alternative fuels: bio-fuels, electric power and fuel gases, taking into account the processes and constraints involved in the production of these fuels. (J.S.)

  11. World Gas Conference 1997. Working committee H. Liquefied gases

    1997-01-01

    This volume of the proceedings contains the report of the International Gas Union's Working Committee H, Liquefied gases, and oral and poster papers presented at the conference. The committee report and each paper have been abstracted separately. (LN)

  12. [Gases in vitreoretinal surgery].

    Janco, L; Vida, R; Bartos, M; Villémová, K; Izák, M

    2012-02-01

    To evaluate the importance and benefits of using gases in vitreoretinal surgery. The gases represent a wide group of substances used in eye surgery for more than 100 years. The role of intraocular gases in vitreoretinal surgery is irreplaceable. Their use is still considered to be the "gold standard". An important step in eye surgery was the introduction of expanding gases--sulfur hexafluoride and perfluorocarbons into routine clinical practice. The most common indications for the use of intraocular gases are: retinal detachment, idiopathic macular hole, complications of vitreoretinal surgery and others. The introduction of intraocular gases into routine clinical practice, along with other modern surgical techniques resulted in significant improvement of postoperative outcomes in a wide range of eye diseases. Understanding the principles of intraocular gases use brings the benefits to the patient and physician as well. Due to their physical and chemical properties they pose far the best and most appropriate variant of intraocular tamponade. Gases also bring some disadvantages, such as difficulties in detailed fundus examination, visual acuity testing, ultrasonographic examination, difficulties in application of intravitreal drugs or reduced possibility of retina laser treatment. The gases significantly change optical system properties of the eye. The use of gases in vitreoretinal surgery has significantly increased success rate of retinal detachment surgery, complicated posterior segment cases, trauma, surgery of the macula and other diseases.

  13. Extraction with supercritical gases

    Schneider, G M; Wilke, G; Stahl, E

    1980-01-01

    The contents of this book derives from a symposium on the 5th and 6th of June 1978 in the ''Haus der Technik'' in Essen. Contributions were made to separation with supercritical gases, fluid extraction of hops, spices and tobacco, physicochemical principles of extraction, phase equilibria and critical curves of binary ammonia-hydrocarbon mixtures, a quick method for the microanalytical evaluation of the dissolving power of supercritical gases, chromatography with supercritical fluids, the separation of nonvolatile substances by means of compressed gases in countercurrent processes, large-scale industrial plant for extraction with supercritical gases, development and design of plant for high-pressure extraction of natural products.

  14. Handbook of purified gases

    Schoen, Helmut

    2015-01-01

    Technical gases are used in almost every field of industry, science and medicine and also as a means of control by government authorities and institutions and are regarded as indispensable means of assistance. In this complete handbook of purified gases the physical foundations of purified gases and mixtures as well as their manufacturing, purification, analysis, storage, handling and transport are presented in a comprehensive way. This important reference work is accompanied with a large number of Data Sheets dedicated to the most important purified gases.  

  15. Gases in molten salts

    Tomkins, RPT

    1991-01-01

    This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

  16. Effect of air-polluting gases on plant metabolism

    Ziegler, I

    1972-01-01

    Among the air-polluting gases, SO/sub 2/, ozone, peroxyacetylnitrate (PAN) and fluorine are those whose action is studied most. This review tries to show the connection between the well-known macroscopic symptoms, on the one hand, the the primary point of attack at the enzymatic level, the changes in the plant's metabolism, and the microscopic and electronmicroscopic results, on the other. PAN and ozone, which originate through the action of sunlight on auto-exhausts, cause the strong oxidizing character of this type of smog. Their primary point of attack seems to be their oxidizing effect on protein SH-groups. PAN in special oxidizes the SH-groups of a photoreducible disulfide containing chloroplast protein, thus blocking photosynthesis. SO/sub 2/, which originates from combustion of coal and petroleum as well as from roasting of sulfur-containing ores, causes the reductive character of this type of smog. SO/sub 2/ has a special position among the air-polluting gases because it can be incorporated without damaging effect into the normal sulfur metabolism up to a certain level. After exceeding this limit, it causes a rapid depression of photosynthesis. F/sup -/ is bound as a salt in the cell wall or in the cell vacuole and is thereby prevented from its damaging effect on metabolic processes up to a certain level. Upon exceeding this, it acts mainly on the enzymes of carbohydrate metabolism. In a few examples it is shown in which way the collapse of cell compartmentation causes the loss of regulatory mechanisms of the cell. The influence of internal (genetic conditions, physiological age etc.) and external (light, temperature, humidity etc.) factors on the general metabolism, and, in this way, on the sensitivity of the plant to air-polluting gases, is shown. 195 references.

  17. Kinetic theory of gases

    Kauzmann, Walter

    2012-01-01

    Monograph and text supplement for first-year students of physical chemistry focuses chiefly on the molecular basis of important thermodynamic properties of gases, including pressure, temperature, and thermal energy. 1966 edition.

  18. AC BREAKDOWN IN GASES

    electron- emission (multipactor) region, and (3) the low-frequency region. The breakdown mechanism in each of these regions is explained. An extensive bibliography on AC breakdown in gases is included.

  19. Reale Gase, tiefe Temperaturen

    Heintze, Joachim

    Wir werden uns in diesem Kapitel zunächst mit der van der Waals'schen Zustandsgleichung befassen. In dieser Gleichung wird versucht, die Abweichungen, die reale Gase vom Verhalten idealer Gase zeigen, durch physikalisch motivierte Korrekturterme zu berücksichtigen. Es zeigt sich, dass die van derWaals-Gleichung geeignet ist, nicht nur die Gasphase, sondern auch die Phänomene bei der Verflüssigung von Gasen und den kritischen Punkt zu beschreiben.

  20. Gases in uranium exploration

    Wright, R.J.; Pacer, J.C.

    1981-01-01

    Interest continues to grow in the use of helium and radon detection as a uranium exploration tool because, in many instances, these radiogenic gases are the only indicators of deeply buried mineralization. The origin of these gases, their migration in the ground, the type of samples and measurement techniques are discussed. Case histories of comparative tests conducted on known uranium deposits at three geologically diverse sites in the United States of America are also presented. (author)

  1. Curiosities of arithmetic gases

    Bakas, I.; Bowick, M.J.

    1991-01-01

    Statistical mechanical systems with an exponential density of states are considered. The arithmetic analog of parafermions of arbitrary order is constructed and a formula for boson-parafermion equivalence is obtained using properties of the Riemann zeta function. Interactions (nontrivial mixing) among arithmetic gases using the concept of twisted convolutions are also introduced. Examples of exactly solvable models are discussed in detail

  2. Strongly interacting Fermi gases

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  3. Radiation effects in gases

    Leonhardt, J.W.

    1985-01-01

    Problems in the studies of radiation effects in gases are discussed. By means of ionization- excitation- and electron-capture yields various applications are characterized: ionization detectors, X-ray detectors, radionuclide battery, and radiation-induced chemical gas-phase reactions. Some new results of basic research in respect to the SO 2 oxidation are discussed. (author)

  4. The greenhouse effect gases

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the greenhouse effect gases. It presents the greenhouses effect as a key component of the climate system, the impacts of the human activity, the foreseeable consequences of global warming, the Kyoto protocol and Total commitment in the domain. (A.L.B.)

  5. Process of radioactive waste gases

    Queiser, H.; Schwarz, H.; Schroter, H.J.

    1975-01-01

    A method is described in which the radiation level of waste gases from nuclear power plants containing both activation and fission gases is controlled at or below limits permitted by applicable standards by passing such gases, prior to release to the atmosphere, through an adsorptive delay path including a body of activated carbon having the relation to the throughput and character of such gases. (U.S.)

  6. Fuel gases in Algeria

    Arachiche, B.; Elandaloussi, H.

    1996-01-01

    For a country like Algeria, fuel gases represent an important economical challenge. To answer the increasing energy demand in the transportation sector, the use of fuel gases allows to preserve the petroleum reserves and to create specific industrial structures devoted to LPG-f (liquefied petroleum gas-fuel) and NGV (natural gas for vehicles). This paper presents the energy policy of Algeria, its reserves, production, and exportations of hydrocarbons and the internal rational use of energy sources according to its economic and environmental policy and to its internal needs. The energy consumption of Algeria in the transportation sector represents 2/3 of the petroleum products consumed in the internal market and follows a rapid increase necessary to the socio-economic development of the country. The Algerian experience in fuel gases is analysed according to the results of two successive experimentation periods for the development of NGV before and after 1994, and the resulting transportation and distribution network is described. The development of LPG-f has followed also an experimental phase for the preparation of regulation texts and a first statement of the vehicles conversion to LPG-f is drawn with its perspectives of development according to future market and prices evolutions. (J.S.)

  7. On Classical Ideal Gases

    Laurent Chusseau

    2013-02-01

    Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.

  8. Removing radioactive noble gases from nuclear process off-gases

    Lofredo, A.

    1977-01-01

    A system is claimed for separating, concentrating and storing radioactive krypton and xenon in the off-gases from a boiling water reactor, wherein adsorption and cryogenic distillation are both efficiently used for rapid and positive separation and removal of the radioactive noble gases, and for limiting such gases in circulation in the system to low inventory at all times, and wherein the system is self-regulating to eliminate operator options or attention

  9. Selective noble gases monitoring

    Janecka, S.; Jancik, O.; Kapisovsky, V.; Kubik, I.; Sevecka, S.

    1995-01-01

    The monitoring of leak releases from ventilation stack of NPP requires a system by several orders more sensitive then currently used radiometer Kalina, designed to cover the range up to a design-based accident. To reach this goal a noble gases monitor with a germanium detector (MPVG) has been developed. It enables nuclide selective monitoring of current value of volume activity of particular nuclides in ventilation stack and daily releases of noble gases (balancing). MPVG can be viewed as a system build of three levels of subsystem: measuring level; control level; presentation level. Measuring level consists of gamma-spectroscopy system and operational parameters monitoring unit (flow rate, temperature, humidity). Control level provides communication between presentation and measuring level, acquisition of operational parameters and power supply. The presentation level of MPVG enables: 1) the measured data storage in predetermined time intervals; 2) the presentation of measured and evaluated values of radiation characteristics. The monitored radionuclides - default set: argon-41, krypton-85m, krypton-87, krypton-88, krypton-89, xenon-131m, xenon-133, xenon-133m, xenon-135, xenon-135m, xenon-137 and xenon-138. The values of volume activities observed at maximum releases have been approximately ten times higher. In that case in balancing some other nuclides exceed corresponding detection limits: 88 Kr(67; 22) Bq/m 3 ; 85m Kr(17; 7) Bq/m 3 ; 135m Xe(7.1; 0.5) Bq/m 3 ; 138 Xe(5.9; 0.9) Bq/m 3 . (J.K.)

  10. Selective noble gases monitoring

    Janecka, S; Jancik, O; Kapisovsky, V; Kubik, I; Sevecka, S [Nuclear Power Plants Research Institute, a.s., Trnava (Slovakia)

    1996-12-31

    The monitoring of leak releases from ventilation stack of NPP requires a system by several orders more sensitive then currently used radiometer Kalina, designed to cover the range up to a design-based accident. To reach this goal a noble gases monitor with a germanium detector (MPVG) has been developed. It enables nuclide selective monitoring of current value of volume activity of particular nuclides in ventilation stack and daily releases of noble gases (balancing). MPVG can be viewed as a system build of three levels of subsystem: measuring level; control level; presentation level. Measuring level consists of gamma-spectroscopy system and operational parameters monitoring unit (flow rate, temperature, humidity). Control level provides communication between presentation and measuring level, acquisition of operational parameters and power supply. The presentation level of MPVG enables: 1) the measured data storage in predetermined time intervals; 2) the presentation of measured and evaluated values of radiation characteristics. The monitored radionuclides - default set: argon-41, krypton-85m, krypton-87, krypton-88, krypton-89, xenon-131m, xenon-133, xenon-133m, xenon-135, xenon-135m, xenon-137 and xenon-138. The values of volume activities observed at maximum releases have been approximately ten times higher. In that case in balancing some other nuclides exceed corresponding detection limits: {sup 88}Kr(67; 22) Bq/m{sup 3}; {sup 85m}Kr(17; 7) Bq/m{sup 3}; {sup 135m}Xe(7.1; 0.5) Bq/m{sup 3}; {sup 138}Xe(5.9; 0.9) Bq/m{sup 3}. (J.K.).

  11. Canonical partition functions: ideal quantum gases, interacting classical gases, and interacting quantum gases

    Zhou, Chi-Chun; Dai, Wu-Sheng

    2018-02-01

    In statistical mechanics, for a system with a fixed number of particles, e.g. a finite-size system, strictly speaking, the thermodynamic quantity needs to be calculated in the canonical ensemble. Nevertheless, the calculation of the canonical partition function is difficult. In this paper, based on the mathematical theory of the symmetric function, we suggest a method for the calculation of the canonical partition function of ideal quantum gases, including ideal Bose, Fermi, and Gentile gases. Moreover, we express the canonical partition functions of interacting classical and quantum gases given by the classical and quantum cluster expansion methods in terms of the Bell polynomial in mathematics. The virial coefficients of ideal Bose, Fermi, and Gentile gases are calculated from the exact canonical partition function. The virial coefficients of interacting classical and quantum gases are calculated from the canonical partition function by using the expansion of the Bell polynomial, rather than calculated from the grand canonical potential.

  12. Economic Hazardous Gases Management for SOX Removal from Flue Gases

    Isaack, S.L.; Mohi, M.A.; Mohamed, S.T.

    1995-01-01

    Hazardous gases emerging from industries accumulate as pollutants in air and falls as acid rains resulting also in water and soil pollution. To minimize environmental pollution, the present process is suggested in order to desulfurize flue gases resulting from burning fuel oil in a 100/MWh steam power plant. The process makes use of the cheap Ca C O 3 powder as the alkaline material to sequistre the sulphur oxide gases. The resulting sulphur compounds, namely calcium sulphate and gypsum have a great market demand as reducing and sulphiting agents in paper industry and as an important building material. About 44000 ton of gypsum could be produced yearly when treating flue gases resulting from a 100 MWh unit burning fuel oil. Feasibility study shows that a great return on investment could be achieved when applying the process. 1 fig

  13. Avalanches in insulating gases

    Verhaart, H.F.A.

    1982-01-01

    Avalanches of charged particles in gases are often studied with the ''electrical method'', the measurement of the waveform of the current in the external circuit. In this thesis a substantial improvement of the time resolution of the measuring setup, to be used for the electrical method, is reported. The avalanche is started by an N 2 -laser with a pulse duration of only 0.6 ns. With this laser it is possible to release a high number of primary electrons (some 10 8 ) which makes it possible to obtain sizeable signals, even at low E/p values. With the setup it is possible to analyze current waveforms with a time resolution down to 1.4 ns, determined by both the laser and the measuring system. Furthermore it is possible to distinguish between the current caused by the electrons and the current caused by the ions in the avalanche and to monitor these currents simultaneously. Avalanche currents are measured in N 2 , CO 2 , O 2 , H 2 O, air of varying humidity, SF 6 and SF 6 /N 2 mixtures. Depending on the nature of the gas and the experimental conditions, processes as diffusion, ionization, attachment, detachment, conversion and secondary emission are observed. Values of parameters with which these processes can be described, are derived from an analysis of the current waveforms. For this analysis already published theories and new theories described in this thesis are used. The drift velocity of both the electrons and the ions could be easily determined from measured avalanche currents. Special attention is paid to avalanches in air becasue of the practical importance of air insulation. (Auth.)

  14. Noble gases solubility in water

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  15. Quotation systems for greenhouse gases

    Trong, Maj Dang

    2000-01-01

    The article surveys recommendations from a Norwegian committee for implementing at a national level, the Kyoto protocol aims for reducing the total emissions of greenhouse gases from the industrial countries through quotation systems

  16. Greenhouse gases and global warming

    1995-01-01

    From previous articles we have learned about the complexities of our environment, its atmosphere and its climate system. we have also learned that climate change and, therefore global warm and cool periods are naturally occurring phenomena. Moreover, all scientific evidence suggests that global warming, are likely to occur again naturally in the future. However, we have not yet considered the role of the rates of climate change in affecting the biosphere. It appears that how quickly the climate changes may be more important than the change itself. In light of this concern, let us now consider the possibility that, is due to human activity. We may over the next century experience global warming at rates and magnitudes unparalleled in recent geologic history. The following questions are answered; What can we learn from past climates? What do we know about global climates over the past 100 years? What causes temperature change? What are the greenhouse gases? How much have concentration of greenhouse gases increased in recent years? Why are increases in concentrations of greenhouse of concern? What is the e nhanced greenhouse effect ? How can human activity impact the global climate? What are some reasons for increased concentrations of greenhouse gases? What are fossil fuel and how do they transform into greenhouse gases? Who are the biggest emitters of greenhouse gases? Why are canada per capita emissions of greenhouse gases relatively high? (Author)

  17. Oral Cancer

    Oral cancer can form in any part of the mouth. Most oral cancers begin in the flat cells that cover the ... your mouth, tongue, and lips. Anyone can get oral cancer, but the risk is higher if you are ...

  18. Radioactive gases monitor system: tritium, radon, noble gases

    Egey, J.Z.; Matatagui, E.

    2015-01-01

    A system for monitoring the radioactive gases tritium, radon and noble gases is described. We present the description of the sensor and the associated electronics that have been developed to monitor the presence of radioactive gases in air or other gaseous effluents. The system has a high sensitivity and a wide range of operation. The sensor is an ionization chamber, featuring the internal circulation of the gas to monitor and the associated electronics has a resolution better than 10 E-15A (fA). It allows the detection of the individual pulses that are produced during the alpha decay of radon and its daughter elements. The measurement system is made up of a commercial data acquisition system connected to a computer. The acquired data is presented on a graphical display and it is stored for later processing and analysis. We have a system that is of simple construction and versatile. Here we present the experimental results. (authors) [es

  19. Gases and carbon in metals

    Jehn, H.; Fromm, E.; Hoerz, G.

    1978-01-01

    This issue is part of a series of data on 'gases and carbon in metals'. The present survey includes results from papers dealing with gases and carbon in actinides and recommends critically selected data for each element. Firstly data od binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility limit, dissociation pressure of compunds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas adsorption and gas desorption kinetics, compound formation, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. Within a ternary system the topics are arranged in the same way as in binary systems. (HB) [de

  20. Effect of naphtha diluent on greenhouse gases and reduced sulfur compounds emissions from oil sands tailings.

    Gee, Kathleen F; Poon, Ho Yin; Hashisho, Zaher; Ulrich, Ania C

    2017-11-15

    The long-term storage of oil sands tailings has resulted in the evolution of greenhouse gases (CH 4 and CO 2 ) as a result of residual organics biodegradation. Recent studies have identified black, sulfidic zones below the tailings-water interface, which may be producing toxic sulfur-containing gases. An anaerobic mesocosm study was conducted over an 11-week period to characterize the evolution of CH 4 , CO 2 and reduced sulfur compounds (RSCs) (including H 2 S) in tailings as it relates to naphtha-containing diluent concentrations (0.2, 0.8, and 1.5% w/v) and microbial activity. Our results showed that RSCs were produced first at 0.12μmol°RSCs/mL MFT (1.5% w/v diluent treatment). RSCs contribution (from highest to lowest) was H 2 S and 2-methylthiophene>2.5-dimethylthiophene>3-methylthiophene>thiofuran>butyl mercaptan>carbonyl sulfide, where H 2 S and 2-methylthiophene contributed 81% of the gas produced. CH 4 and CO 2 production occurred after week 5 at 40.7μmolCH 4 /mL MFT and 5.9μmolCO 2 /mL MFT (1.5% w/v diluent treatment). The amount of H 2 S and CH 4 generated is correlated to the amount of diluent present and to microbial activity as shown by corresponding increases in sulfate-reducers' Dissimilatory sulfite reductase (DsrAB) gene and methanogens' methyl-coenzyme M reductase (MCR) gene. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Desulphurization of exhaust gases in chemical processes

    Asperger, K.; Wischnewski, W.

    1981-01-01

    The sulfur content of exhaust gases can be reduced by: desulphurization of fuels; modification of processes; or treatment of resultant gases. In this paper a few selected examples from the chemical industry in the German Democratic Republic are presented. Using modified processes and treating the resultant gases, the sulphuric content of exhaust gases is effectively reduced. Methods to reduce the sulfur content of exhaust gases are described in the field of production of: sulphuric acid; viscose; fertilizers; and paraffin.

  2. Process for separating radioactive gases

    Kimura, Shigeru; Awada, Yoshihisa.

    1976-01-01

    Object: To efficiently and safely separate and recover raw gases such as krypton which requires radioactive attenuation by a long term storage. Structure: A mixture of krypton and xenon is separated by liquefaction from raw gases at a first distillation column, using latent heat of liquid nitrogen. The krypton and xenon mixture separated by liquefaction at the first distillation column is separated into krypton and xenon, by controlling operation pressure of a second distillation column at about 3 - 5 atm., using sensible heat of low temperature nitrogen gas discharged from a top of the first distillation column and a condenser. (Aizawa, K.)

  3. The ideal gases of tachyons

    Mrowczynski, St.

    1984-01-01

    The formalism of statistical mechanics of particles slower than light has been considered from the point of view of the application of this formalism for the description of tachyons. Properties of ideal gases of tachyons have been discussed in detail. After finding general formulae for quantum, Bose and Fermi gases the classical limit has been considered. It has been shown that Bose-Einstein condensation occurs. The tachyon gas of bosons violates the third principle of thermodynamics. Degenerated Fermi gas has been considered and in this case the entropy vanishes at zero temperature. Difficulties of formulating covariant statistical mechanics have been discussed

  4. A microscope for Fermi gases

    Omran, Ahmed

    2016-01-01

    This thesis reports on a novel quantum gas microscope to investigate many-body systems of fermionic atoms in optical lattices. Single-site resolved imaging of ultracold lattice gases has enabled powerful studies of bosonic quantum many-body systems. The extension of this capability to Fermi gases offers new prospects to studying complex phenomena of strongly correlated systems, for which numerical simulations are often out of reach. Using standard techniques of laser cooling, optical trapping, and evaporative cooling, ultracold Fermi gases of 6 Li are prepared and loaded into a large-scale 2D optical lattice of flexible geometry. The atomic distribution is frozen using a second, short-scaled lattice, where we perform Raman sideband cooling to induce fluorescence on each atom while maintaining its position. Together with high-resolution imaging, the fluorescence signals allow for reconstructing the initial atom distribution with single-site sensitivity and high fidelity. Magnetically driven evaporative cooling in the plane allows for producing degenerate Fermi gases with almost unity filling in the initial lattice, allowing for the first microscopic studies of ultracold gases with clear signatures of Fermi statistics. By preparing an ensemble of spin-polarised Fermi gases, we detect a flattening of the density profile towards the centre of the cloud, which is a characteristic of a band-insulating state. In one set of experiments, we demonstrate that losses of atom pairs on a single lattice site due to light-assisted collisions are circumvented. The oversampling of the second lattice allows for deterministic separation of the atom pairs into different sites. Compressing a high-density sample in a trap before loading into the lattice leads to many double occupancies of atoms populating different bands, which we can image with no evidence for pairwise losses. We therefore gain direct access to the true number statistics on each lattice site. Using this feature, we can

  5. Transport processes in ionized gases

    Kremer, G.M.

    1997-01-01

    Based on kinetic theory of gases and on the combined of Chapman-Enskog and Grad, the laws of Ohm, Fourier and Navier-Stokes are derived for a non-relativistic fully ionized gas. Moreover, the combined method is applied to the BGK model of the relativistic Boltzmann equation and the Ohm's law is derived for a relativistic fully ionized gas. (author)

  6. Stratospheric aerosols and precursor gases

    1982-01-01

    Measurements were made of the aerosol size, height and geographical distribution, their composition and optical properties, and their temporal variation with season and following large volcanic eruptions. Sulfur-bearing gases were measured in situ in the stratosphere, and studied of the chemical and physical processes which control gas-to-particle conversion were carried out in the laboratory.

  7. Permeability of cork to gases.

    Faria, David P; Fonseca, Ana L; Pereira, Helen; Teodoro, Orlando M N D

    2011-04-27

    The permeability of gases through uncompressed cork was investigated. More than 100 samples were assessed from different plank qualities to provide a picture of the permeability distribution. A novel technique based on a mass spectrometer leak detector was used to directly measure the helium flow through the central area of small disks 10 mm in diameter and 2 mm thick. The permeability for nitrogen, oxygen, and other gases was measured by the pressure rise technique. Boiled and nonboiled cork samples from different sections were evaluated. An asymmetric frequency distribution ranging 3 orders of magnitude (roughly from 1 to 1000 μmol/(cm·atm·day)) for selected samples without macroscopic defects was found, having a peak below 100 μmol/(cm·atm·day). Correlation was found between density and permeability: higher density samples tend to show lower permeability. However, boiled cork showed a mean lower permeability despite having a lower density. The transport mechanism of gases through cork was also examined. Calculations suggest that gases permeate uncompressed cork mainly through small channels between cells under a molecular flow regime. The diameter of such channels was estimated to be in the range of 100 nm, in agreement with the plasmodesmata size in the cork cell walls.

  8. Oral myiasis

    Thalaimalai Saravanan

    2015-01-01

    Full Text Available Myiasis is a pathologic condition in humans occurring because of parasitic infestation. Parasites causing myiasis belong to the order Diptera. Oral myiasis is seen secondary to oral wounds, suppurative lesions, and extraction wounds, especially in individuals with neurological deficit. In such cases, neglected oral hygiene and halitosis attracts the flies to lay eggs in oral wounds resulting in oral myiasis. We present a case of oral myiasis in 40-year-old male patient with mental disability and history of epilepsy.

  9. Soliton Gases and Generalized Hydrodynamics

    Doyon, Benjamin; Yoshimura, Takato; Caux, Jean-Sébastien

    2018-01-01

    We show that the equations of generalized hydrodynamics (GHD), a hydrodynamic theory for integrable quantum systems at the Euler scale, emerge in full generality in a family of classical gases, which generalize the gas of hard rods. In this family, the particles, upon colliding, jump forward or backward by a distance that depends on their velocities, reminiscent of classical soliton scattering. This provides a "molecular dynamics" for GHD: a numerical solver which is efficient, flexible, and which applies to the presence of external force fields. GHD also describes the hydrodynamics of classical soliton gases. We identify the GHD of any quantum model with that of the gas of its solitonlike wave packets, thus providing a remarkable quantum-classical equivalence. The theory is directly applicable, for instance, to integrable quantum chains and to the Lieb-Liniger model realized in cold-atom experiments.

  10. Noble Gases in Lakes and Ground Waters

    Kipfer, Rolf; Aeschbach-Hertig, Werner; Peeters, Frank; Stute, Marvin

    2002-01-01

    In contrast to most other fields of noble gas geochemistry that mostly regard atmospheric noble gases as 'contamination,' air-derived noble gases make up the far largest and hence most important contribution to the noble gas abundance in meteoric waters, such as lakes and ground waters. Atmospheric noble gases enter the meteoric water cycle by gas partitioning during air / water exchange with the atmosphere. In lakes and oceans noble gases are exchanged with the free atmosphere at the surface...

  11. Oral cancer

    Cancer - mouth; Mouth cancer; Head and neck cancer; Squamous cell cancer - mouth; Malignant neoplasm - oral ... National Cancer Institute. PDQ lip and oral cavity cancer ... September 25, 2015. www.cancer.gov/types/head-and-neck/hp/lip- ...

  12. Oral Ketamine

    Oral Ketamine: A Four-years Experience in ... Key words: Oral Ketamine, Premedication and Oncology. .... form of a letter published in 19835. .... Acta. Anaesthesiol Scandinavica, 1998; 42: 750-758. 4. Murray P. Substitution of another opioid ...

  13. Centrifugal separation of mixture gases

    Zhou, M.S.; Chen, W.N.; Yin, Y.T.

    2008-01-01

    An attempt for single centrifugal separation of mixtures with different molecular formula was presented in this paper. The mixtures of SF 6 and CCl 3 F, and SF 6 and CCl 4 were chosen as the processing gases, which were prepared in three mass ratios, 0.5, 0.8 and 0.2, respectively. The separating characteristics such as the overall separation factors and the variation of cuts were studied. (author)

  14. Landfill gases and some effects on vegetation

    Franklin B. Flower; Ida A. Leone; Edward F. Gilman; John J. Arthur

    1977-01-01

    Gases moving from refuse landfills through soil were studied in New Jersey. The gases, products of anaerobic decomposition of organic matter in the refuse, caused injury and death of peach trees, ornamentals, and commercial farm crops, and create possible hazards to life and property because of the entrance of combustible gases into residences. Remedial measures are...

  15. Rhenium(V) complexes with sulfur-containing amino acids

    Gagieva, S.Ch.; Tautieva, M.A.; Tsaloev, A.T.; Galimov, Yu.B.; Gagieva, L.Ch.; Belyaeva, T.N.

    2007-01-01

    Rhenium(V) complexes with 2-amino-4-(methylthio)butanoic acid (methionine, Met) and 2-amino-3-sulfopropionic acid (cysteine, Cys) have been synthesized. Depending on the initial reagent ratio, the resulting complexes contain one or two ligand molecules. On heating the compounds with one amino acid molecule, two hydrogen halide molecules are removed at 128-132 deg C to form a molecular complex. The composition, structure, and thermal stability of the complexes have been studied by elemental analysis, conductometry, IR spectroscopy, NMR, and mass spectrometry [ru

  16. Sulfur-containing heterocyclic compounds with potential antidiabetic activity

    E. A. Savateeva

    2014-12-01

    Full Text Available The essential link in the pathogenesis of diabetes mellitus and its complications is a non-enzymatic glycosylation of proteins. However, modern endocrinology lacks of clinically effective pharmaceuticals for its correction. The screening of 23 derivatives of 1,3,4-thiadiazine the ability to inhibit the reaction of non-enzymatic glycosylation of proteins in vitro was held, and 11 the most active compounds of them were selected, also the relationship «structure – activity» was investigated. An essential part of the pathogenesis of diabetes mellitus and its complications is non-enzymatic glycosylation of proteins. However, modern endocrinology lacks clinically effective medicines for its correction.

  17. Durability of solid oxide fuel cells using sulfur containing fuels

    Hagen, Anke; Rasmussen, Jens Foldager Bregnballe; Thydén, Karl Tor Sune

    2011-01-01

    The usability of hydrogen and also carbon containing fuels is one of the important advantages of solid oxide fuel cells (SOFCs), which opens the possibility to use fuels derived from conventional sources such as natural gas and from renewable sources such as biogas. Impurities like sulfur compounds...... are critical in this respect. State-of-the-art Ni/YSZ SOFC anodes suffer from being rather sensitive towards sulfur impurities. In the current study, anode supported SOFCs with Ni/YSZ or Ni/ScYSZ anodes were exposed to H2S in the ppm range both for short periods of 24h and for a few hundred hours. In a fuel...

  18. Greenhouse Gases and Animal Agriculture

    Takahashi, J. (ed.) [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido (Japan); Young, B.A. (ed.) [The University of Queensland, Gatton, Queensland 4343 (Australia)

    2002-07-01

    Reports from interdisciplinary areas including microbiology, biochemistry, animal nutrition, agricultural engineering and economics are integrated in this proceedings. The major theme of this book is environmental preservation by controlling release of undesirable greenhouse gases to realize the sustainable development of animal agriculture. Technology exists for the effective collection of methane generated from anaerobic fermentation of animal effluent and its use as a biomass energy source. Fossil fuel consumption can be reduced and there can be increased use of locally available energy sources. In addition, promoting environmentally-conscious agriculture which does not rely on the chemical fertilizer can be realized by effective use of animal manure and compost products.

  19. Mechanics of liquids and gases

    Loitsyanskii, L G; Jones, W P

    1966-01-01

    Mechanics of Liquids and Gases, Second Edition is a 10-chapter text that covers significant revisions concerning the dynamics of an ideal gas, a viscous liquid and a viscous gas.After an expanded introduction to the fundamental properties and methods of the mechanics of fluids, this edition goes on dealing with the kinetics and general questions of dynamics. The next chapters describe the one-dimensional pipe flow of a gas with friction, the elementary theory of the shock tube; Riemann's theory of the wave propagation of finite intensity, and the theory of plane subsonic and supersonic flows.

  20. Throat gases against the CO2

    Michaut, C.

    2006-01-01

    The steel production needs carbon consumption and generates carbon dioxide, the main greenhouse gases. It represents about 6 % of the greenhouse gases emissions in the world. That is why the steel industry began last year a research program, Ideogaz, to reduce its CO 2 releases. The first results on the throat gases recovery seems very promising: it uses 25 % less of carbon. The author presents the program and the main technical aspects of the method. (A.L.B.)

  1. Optical Lattice Gases of Interacting Fermions

    2015-12-02

    interacting Fermi gases has topological properties similar to the conventional chiral p- wave state. These include a non-zero Chern number and the...interacting cold gases with broad impacts on the interfaces with condensed matter and particle physics . Applications and experiments of some of the physics ...AFRL-AFOSR-VA-TR-2016-0016 Optical Lattice Gases of Interacting Fermions Wensheng Vincent Liu UNIVERSITY OF PITTSBURGH Final Report 12/02/2015

  2. Noble gases in nuclear medicine

    Calderon, M.; Burdine, J.A.

    1973-01-01

    Radioactive noble gases have made a significant contribution to diagnostic nuclear medicine. In the area of regional assessment of pulmonary function, 133 Xe has had its greatest clinical impact. Following a breath of 133 Xe gas, pulmonary ventilation can be measured using a scintillation camera or other appropriate radiation detector. If 133 Xe dissolved in saline is injected intravenously, both pulmonary capillary perfusion and ventilation can be measured since 90 percent of the highly insoluble xenon escapes into the alveoli during the first passage through the lungs. Radionuclide pulmonary function tests provide the first qualitative means of assessing lung ventilation and blood flow on a regional basis, and have recently been extended to include quantification of various parameters of lung function by means of a small computer interfaced to the scintillation camera. 133 Xe is also used in the measurement of organ blood flow following injection into a vessel leading into an organ such as the brain, heart kidneys, or muscles

  3. Oral Hygiene

    Sørensen, Marie Toftdahl; Villadsen, Dorte Buxbom

    The aim of the study was to explore how adults with schizo- phrenia describe their lived experiences with oral hygiene. 23 adults with schizophrenia were interviewed within a period of four months in late 2015. Transcriptions of the interviews were analysed using the Reflective Lifeworld Research...... health care professionals and adults with schizophrenia in order to improve oral health, well-being and recovery....

  4. Oral Hygiene

    Villadsen, Dorte Buxbom; Sørensen, Marie Toftdahl

    2017-01-01

    The aim of the study is to explore how adults with schizophrenia describe their lived experiences with oral hygiene. 23 adults with schizophrenia were interviewed within a period of four months in late 2015. Transcriptions of the interviews were analysed using the Reflective Lifeworld Research ph...... health care professionals and adults with schizophrenia in order to improve oral health, well-being and recovery....

  5. Energy efficiency and greenhouse gases

    Hamburg, A.; Martins, A.; Pesur, A.; Roos, I.

    1996-01-01

    Estonia's energy balance for 1990 - 1994 is characterized by the dramatic changes in the economy after regaining independence in 1991. In 1990 - 1993, primary energy supply decreased about 1.9 times. The reasons were a sharp decrease in exports of electric energy and industrial products, a steep increase in fuel prices and the transition from the planned to a market-oriented economy. Over the same period, the total amount of emitted greenhouse gases decreased about 45%. In 1993, the decrease in energy production and consumption stopped, and in 1994, a moderate increase occurred (about 6%), which is a proof stabilizing economy. Oil shale power engineering will remain the prevailing energy resource for the next 20 - 25 years. After stabilization, the use of oil shale will rise in Estonia's economy. Oil shale combustion in power plants will be the greatest source of greenhouse gases emissions in near future. The main problem is to decrease the share of CO 2 emissions from the decomposition of carbonate part of oil shale. This can be done by separating limestone particles from oil shale before its burning by use of circulating fluidized bed combustion technology. Higher efficiency of oil shale power plants facilitates the reduction of CO 2 emissions per generated MWh electricity considerably. The prognoses for the future development of power engineering depend essentially on the environmental requirements. Under the highly restricted development scenario, which includes strict limitations to emissions (CO 2 , SO 2 , thermal waste) and a severe penalty system, the competitiveness of nuclear power will increase. The conceptual steps taken by the Estonian energy management should be in compliance with those of neighboring countries, including the development programs of the other Baltic states

  6. 40 CFR 89.312 - Analytical gases.

    2010-07-01

    ... determined to calibration gas tolerances by chromatographic analysis of total hydrocarbons plus impurities or.... (2) Mixtures of gases having the following chemical compositions shall be available: (i) C3H8 and... check gases shall contain propane with 350 ppmC ±75 ppmC hydrocarbon. The three oxygen interference...

  7. Greenhouse Gases Concentrations in the Atmosphere Along ...

    This study investigated effect of vehicular emission on greenhouse gases concentrations along selected roads of different traffic densities in Abeokuta, Ogun State, Nigeria. Nine roads comprised highway, commercial and residential were selected. Greenhouse Gases (GHGs) were determined from both sides of the roads by ...

  8. Specific heats of degenerate ideal gases

    Caruso, Francisco; Oguri, Vitor; Silveira, Felipe

    2017-01-01

    From arguments based on Heisenberg's uncertainty principle and Pauli's exclusion principle, the molar specific heats of degenerate ideal gases at low temperatures are estimated, giving rise to values consistent with the Nerst-Planck Principle (third law of Thermodynamics). The Bose-Einstein condensation phenomenon based on the behavior of specific heat of massive and non-relativistic boson gases is also presented.

  9. Method for storing radioactive rare gases

    Watabe, Atsushi; Nagao, Hiroyuki; Takiguchi, Yukio; Kanazawa, Toshio; Soya, Masataka.

    1975-01-01

    Object: To safely and securely store radioactive rare gases for a long period of time. Structure: The waste gases produced in nuclear power plant are cooled by a cooler and then introduced into a low temperature adsorbing device so that the gases are adsorbed by adsorbents, and then discharged into atmosphere through the purifying gas discharge line. When the radioactive rare gases reach a level of saturation in the amount of adsorption, they are heated and extracted by a suction pump and heated by a heater. The gases are then introduced into an oxygen-impurity removing device and the purified rare gases containing no oxygen and impurities are cooled by a cooler and fed into a gas holder. When the amount of radioactive rare gases stored within the gas holder reaches a given level, they are compressed and sealed by a compressure into a storing cylinder and residual gases in the piping are sucked and recovered into the gas holder, after which the cylinder is removed and stored in a fixed room. (Kamimura, M.)

  10. Oral leukoplakia

    Holmstrup, Palle; Dabelsteen, Erik

    2016-01-01

    The idea of identifying oral lesions with a precancerous nature, i.e. in the sense of pertaining to a pathologic process with an increased risk for future malignant development, of course is to prevent frank malignancy to occur in the affected area. The most common oral lesion with a precancerous...... nature is oral leukoplakia, and for decades it has been discussed how to treat these lesions. Various treatment modalities, such as systemic therapies and surgical removal, have been suggested. The systemic therapies tested so far include retinoids, extracts of green tea, inhibitors of cyclooxygenase-2...

  11. Method of contacting solids and gases

    1942-08-06

    A continuous method is described for contacting solids and gases. The process involves passing a confined stream of gases through an extended path including a treating zone and imposing a pressure on the stream of gases at least sufficient to overcome the resistence of said path to the flow of said gases. A solid in finely divided form is then introduced into said stream of gases, maintaining a vertical column of finely divided solid in fluidized state of a height which will produce a pressure at the column bottom at least equal to the gas pressure at the point of entry of the solids into the stream. The solids then pass from the bottom of the column into the stream.

  12. Oral cancer.

    Gerson, S J

    1990-01-01

    In the U.S. oral cancer accounts for 2.1% of all cancers and 1% of cancer deaths. Two to three times as many males as females are affected. Blacks have more intra-oral cancer than whites, and their incidence and mortality rates have increased in recent years. The etiologic process very likely involves several factors. The major etiologic agents are tobacco (all types) and alcoholic beverages. Herpes simplex virus, human papilloma virus, and Candida have been implicated. Host factors include poor state of dentition, nutritional aberrations, cirrhosis of liver, lichen planus, and immunologic impairmant. Cellular changes include amplification of some oncogenes, alterations in antigen expression, production of gamma-glutamyl transpeptidase, and disturbance of keratin and involucrin production. Experimentally, cancer is readily produced on the hamster cheek pouch and rat oral mucosa. Unlike oral cancer in humans, most experimental lesions are exophytic, and they rarely metastasize.

  13. Kinetic Theory of Granular Gases

    Trizac, Emmanuel [Center of Theoretical Biological Physics, UC San Diego, La Jolla, CA 92093-0374 (United States); Laboratoire de Physique Theorique et Modeles Statistiques, Campus Universitaire, 91405 Orsay (France)

    2005-11-25

    Granular gases are composed of macroscopic bodies kept in motion by an external energy source such as a violent shaking. The behaviour of such systems is quantitatively different from that of ordinary molecular gases: due to the size of the constituents, external fields have a stronger effect on the dynamics and, more importantly, the kinetic energy of the gas is no longer a conserved quantity. The key role of the inelasticity of collisions has been correctly appreciated for about fifteen years, and the ensuing consequences in terms of phase behaviour or transport properties studied in an increasing and now vast body of literature. The purpose of this book is to help the newcomer to the field in acquiring the essential theoretical tools together with some numerical techniques. As emphasized by the authors-who were among the pioneers in the domain- the content could be covered in a one semester course for advanced undergraduates, or it could be incorporated in a more general course dealing with the statistical mechanics of dissipative systems. The book is self-contained, clear, and avoids mathematical complications. In order to elucidate the main physical ideas, heuristic points of views are sometimes preferred to a more rigorous route that would lead to a longer discussion. The 28 chapters are short; they offer exercises and worked examples, solved at the end of the book. Each part is supplemented with a relevant foreword and a useful summary including take-home messages. The editorial work is of good quality, with very few typographical errors. In spite of the title, kinetic theory stricto sensu is not the crux of the matter covered. The authors discuss the consequences of the molecular chaos assumption both at the individual particle level and in terms of collective behaviour. The first part of the book addresses the mechanics of grain collisions. It is emphasized that considering the coefficient of restitution {epsilon} -a central quantity governing the

  14. Kinetic Theory of Granular Gases

    Trizac, Emmanuel

    2005-01-01

    Granular gases are composed of macroscopic bodies kept in motion by an external energy source such as a violent shaking. The behaviour of such systems is quantitatively different from that of ordinary molecular gases: due to the size of the constituents, external fields have a stronger effect on the dynamics and, more importantly, the kinetic energy of the gas is no longer a conserved quantity. The key role of the inelasticity of collisions has been correctly appreciated for about fifteen years, and the ensuing consequences in terms of phase behaviour or transport properties studied in an increasing and now vast body of literature. The purpose of this book is to help the newcomer to the field in acquiring the essential theoretical tools together with some numerical techniques. As emphasized by the authors-who were among the pioneers in the domain- the content could be covered in a one semester course for advanced undergraduates, or it could be incorporated in a more general course dealing with the statistical mechanics of dissipative systems. The book is self-contained, clear, and avoids mathematical complications. In order to elucidate the main physical ideas, heuristic points of views are sometimes preferred to a more rigorous route that would lead to a longer discussion. The 28 chapters are short; they offer exercises and worked examples, solved at the end of the book. Each part is supplemented with a relevant foreword and a useful summary including take-home messages. The editorial work is of good quality, with very few typographical errors. In spite of the title, kinetic theory stricto sensu is not the crux of the matter covered. The authors discuss the consequences of the molecular chaos assumption both at the individual particle level and in terms of collective behaviour. The first part of the book addresses the mechanics of grain collisions. It is emphasized that considering the coefficient of restitution ε -a central quantity governing the inelasticity of

  15. The storage of greenhouse gases

    Herzog, H.; Kaarstad, O.; Eliasson, B

    2000-01-01

    Since 1850, that is to say the beginning of the industrial era,the concentration of carbon dioxide in the atmosphere has risen from 280 ppm to 370 ppm, this increase is mainly due to the combustion of fossil fuels. Today fossil fuels represent 85% of all the energy used in the world. Fearing progressive climatic changes, more and more governments become aware of the necessity of reducing the emission of greenhouse gases. A more efficient use of energy and the promoting of renewable energies and of the nuclear energy are the most evident solutions but they appear to be insufficient. A third solution is the storage of carbon dioxide in geological layers. This technique has been put into use since 1996 in Norway. An off-shore natural gas platform injects carbon dioxide in a geological reservoir situated 1000 meters below the ocean bed. The injection of CO 2 could be used in oil fields in order to facilitate the extraction of petroleum. Far more large and efficient reservoirs would be the oceans, they already hold up 40000 10 9 tons of dissolved CO 2 . Even if the double of the carbon dioxide accumulated in the atmosphere since 1850 were injected, the concentration of carbon in sea waters would rise by less than 2%. The safety of CO 2 storage and the impact on the environment of ocean injection sites are being studied. (A.C.)

  16. Greenhouse gases and emissions trading

    LeBlanc, A.; Dudek, D.J.

    1993-01-01

    Global cooperation is essential in cutting greenhouse-gas emissions, say Alice LeBlanc and Daniel J. Dudek of the Environmental Defense in New York City. The first step, they continue, is agreement among nations on an overall global limit for all greenhouse gases, followed by an allocation of the global limit among nations. The agreements must contain effective reporting and monitoring systems and enforcement provisions, they add. The Framework Convention on Climate Change, signed by most nations of the world in Brazil in 1992, provides the foundation for such an agreement, LeBlanc and Dudek note. open-quotes International emissions trading is a way to lower costs and expand reduction options for the benefit of all,close quotes they contend. Under such an arrangement, an international agency would assign allowances, stated in tons of carbon dioxide. Countries would be free to buy and sell allowances, but no country could exceed, in a given year, the total allowances it holds. By emitting less than its allowed amount, a country would accumulate more allowances, which it could sell. The authors claim such a system would offer benefits to the world economy by saving billions of dollars in pollution-reduction costs while still achieving emission limits established in an international agreement

  17. Oral sex.

    1996-04-05

    The Gay and Lesbian Medical Association urges HIV prevention specialists to regard male-to-male oral-genital sex as a low-risk activity and concentrate instead on the danger of unprotected anal intercourse. According to the association, the confusion and mixed messages surrounding oral sex are harming efforts to encourage gay men to make rational choices about truly risky behavior. The recommendations appear in the association's position paper issued March 19, 1996.

  18. Oral Cancer Screening

    ... decrease the risk of oral cavity and oropharyngeal cancer. Oral cavity, pharyngeal, and laryngeal cancer are diseases in ... and treatment of oral cavity, pharyngeal, and laryngeal cancer: Oral Cavity and Oropharyngeal Cancer Prevention Lip and Oral ...

  19. Greenhouse gases study in Amazonia

    D'Amelio, Monica Tais Siqueira

    2006-01-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO 2 sources. The Amazon forest is a significant source of N 2 O by soil process, and CH 4 by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO 2 , CH 4 , CO, H 2 , N 2 O and SF 6 have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO 2 flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO 2 flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H 2 gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO 2 sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and 2005 wet seasons and 2004 dry season comparison it was

  20. Dipolar quantum gases of erbium

    Frisch, A.

    2014-01-01

    Since the preparation of the first Bose-Einstein condensate about two decades ago and the first degenerate Fermi gas following four years later a plethora of fascinating quantum phenomena have been explored. The vast majority of experiments focused on quantum degenerate atomic gases with short-range contact interaction between particles. Atomic species with large magnetic dipole moments, such as chromium, dysprosium, and erbium, offer unique possibilities to investigate phenomena arising from dipolar interaction. This kind of interaction is not only long-range but also anisotropic in character and imprints qualitatively novel features on the system. Prominent examples are the d-wave collapse of a dipolar Bose-Einstein condensate of chromium atoms realized by the group in Stuttgart, the spin magnetization and demagnetization dynamics observed by groups in Stuttgart, Paris, and Stanford, and the deformation of the Fermi surface observed by our group in Innsbruck. This thesis reports on the creation and study of the first Bose-Einstein condensate and degenerate Fermi gas of erbium atoms. Erbium belongs to the lanthanide group of elements and has a large magnetic moment of seven Bohr magneton. In particular, this thesis describes the experimental apparatus and the sequence for producing a dipolar quantum gas. There is an emphasis on the production of the narrow-line magneto-optical trap of erbium since this represents a very efficient and robust laser-cooling scheme that greatly simplifies the experimental procedure. After describing the experimental setup this thesis focuses on several fundamental questions related to the dipolar character of erbium and to its lanthanide nature. A first set of studies centers on the scattering properties of ultracold erbium atoms, including the elastic and the inelastic cross section and the spectrum of Feshbach resonances. Specifically, we observe that identical dipolar fermions do collide and rethermalize even at low temperatures

  1. Thermodynamics of ultracold Fermi gases

    Nascimbene, Sylvain

    2010-01-01

    Complex Hamiltonians from condensed matter, such as the Fermi-Hubbard model, can be experimentally studied using ultracold gases. This thesis describes a new method for determining the equation of state of an ultracold gas, making the comparison with many-body theories straightforward. It is based on the measurement of the local pressure inside a trapped gas from the analysis of its in situ image. We first apply this method to the study of a Fermi gas with resonant interactions, a weakly-interacting 7 Li gas acting as a thermometer. Surprisingly, none of the existing many-body theories of the unitary gas accounts for the equation of state deduced from our study over its full range. The virial expansion extracted from the high-temperature data agrees with the resolution of the three-body problem. At low temperature, we observe, contrary to some previous studies, that the normal phase behaves as a Fermi liquid. Finally we obtain the critical temperature for superfluidity from a clear signature on the equation of state. We also measure the pressure of the ground state as a function of spin imbalance and interaction strength - measure directly relevant to describe the crust of neutron stars. Our data validate Monte-Carlo simulations and quantify the Lee-Huang-Yang corrections to mean-field interactions in low-density fermionic or bosonic superfluids. We show that, in most cases, the partially polarized normal phase can be described as a Fermi liquid of polarons. The polaron effective mass extracted from the equation of state is in agreement with a study of collective modes. (author)

  2. Rare gases in Samoan xenoliths

    Poreda, R. J.; Farley, K. A.

    1992-09-01

    The rare gas isotopic compositions of residual harzburgite xenoliths from Savai'i (SAV locality) and an unnamed seamount south of the Samoan chain (PPT locality) provide important constraints on the rare gas evolution of the mantle and atmosphere. Despite heterogeneous trace element compositions, the rare gas characteristics of the xenoliths from each of the two localities are strikingly similar. SAV and PPT xenoliths have 3He/ 4He ratios of11.1 ± 0.5 R A and21.6 ± 1 R A, respectively; this range is comparable to the 3He/ 4He ratios in Samoan lavas and clearly demonstrates that they have trapped gases from a relatively undegassed reservoir. The neon results are not consistent with mixing between MORB and a plume source with an atmospheric signature. Rather, the neon isotopes reflect either a variably degassed mantle (with a relative order of degassing of Loihi Honda et al. that the 20Ne/ 22Ne ratio in the mantle more closely resembles the solar ratio than the atmospheric one. 40Ar/ 36Ar ratios in the least contaminated samples range from 4,000 to 12,000 with the highest values in the 22 RA PPT xenoliths. There is no evidence for atmospheric 40Ar/ 36Ar ratios in the mantle source of these samples, which indicates that the lower mantle may have 40Ar/ 36Ar ratios in excess of 5,000. Xenon isotopic anomalies in 129Xe and 136Xe are as high as 6%, or about half of the maximum MORB excess and are consistent with the less degassed nature of the Samoan mantle source. These results contradict previous suggestions that the high 3He/ 4He mantle has a near-atmospheric heavy rare gas isotopic composition.

  3. Anaesthetic gases: environmental impact and alternatives

    Little consideration has been given to the environmental impact of anaesthetic gas .... our practice to select gases with a lower environmental impact is also ... is used as raw material for new anaesthetics. ... none in the pipeline.1. Conclusion.

  4. Voluntary reporting of greenhouse gases, 1995

    NONE

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  5. Granular Gases: Probing the Boundaries of Hydrodynamics

    Goldhirsch, I.

    1999-01-01

    The dissipative nature of the particle interactions in granular systems renders granular gases mesoscopic and bearing some similarities to regular gases in the ''continuum transition regime'' where shear rates and/or thermal gradients are very large). The following properties of granular gases support the above claim: (i). Mean free times are of the same order as macroscopic time scales (inverse shear rates); (ii). Mean free paths can be macroscopic and comparable to the system's dimensions; (iii). Typical flows are supersonic; (iv). Shear rates are typically ''large''; (v). Stress fields are scale (resolution) dependent; (vi). Burnett and super-Burnett corrections to both the constitutive relations and the boundary conditions are of importance; (vii). Single particle distribution functions can be far from Gaussian. It is concluded that while hydrodynamic descriptions of granular gases are relevant, they are probing the boundaries of applicability of hydrodynamics and perhaps slightly beyond

  6. Greenhouse gases - observed tendencies contra scenarios

    Groenaas, Sigbjoern

    2006-01-01

    The article presents a study of the increase in greenhouse gases and concludes that it will be necessary to substantially reduce the CO2 concentrations in the atmosphere in order to avoid serious climatic changes

  7. Climate Change, Greenhouse Gases and Aerosols

    user

    their radiative properties are similar to the glass used in a green- house. Greenhouse gases in the Earth's atmosphere absorb 90% of the radiation emitted .... and wind speed and direction in each box is calculated using the physical laws gov-.

  8. Roadside management strategies to reduce greenhouse gases.

    2010-06-01

    Californias Global Warming Solutions Act of 2006 (AB 32), Sustainable Communities and Climate Protection Act : (SB 375), and Executive Order S-14-08 direct Caltrans to develop actions to reduce greenhouse gases (GHGs). Air : pollution reduction is...

  9. Gases for an SSC muon detector

    Christophorou, L.G.; Datskos, P.G.; Carter, J.G.; Tennessee Univ., Knoxville, TN

    1990-01-01

    Recent measurements of electron drift velocities as a function of the density-reduced electric field E/N are reported for a number of unitary gases and the mixtures CO 2 /CH 4 and NH 3 /CF 4 /Ar. Calculated values of the mean electron energy as a function of E/N are also reported for unitary gases and mixtures of CO 2 /CH 4 . 7 refs., 5 figs

  10. Flux Jacobian Matrices For Equilibrium Real Gases

    Vinokur, Marcel

    1990-01-01

    Improved formulation includes generalized Roe average and extension to three dimensions. Flux Jacobian matrices derived for use in numerical solutions of conservation-law differential equations of inviscid flows of ideal gases extended to real gases. Real-gas formulation of these matrices retains simplifying assumptions of thermodynamic and chemical equilibrium, but adds effects of vibrational excitation, dissociation, and ionization of gas molecules via general equation of state.

  11. Pseudogap phenomena in ultracold atomic Fermi gases

    Chen, Qijin; Wang, Jibiao

    2014-01-01

    The pairing and superfluid phenomena in a two-component ultracold atomic Fermi gas is an analogue of Cooper pairing and superconductivity in an electron system, in particular, the high $T_c$ superconductors. Owing to the various tunable parameters that have been made accessible experimentally in recent years, atomic Fermi gases can be explored as a prototype or quantum simulator of superconductors. It is hoped that, utilizing such an analogy, the study of atomic Fermi gases may shed light to ...

  12. Oral candidiasis.

    Millsop, Jillian W; Fazel, Nasim

    2016-01-01

    Oral candidiasis (OC) is a common fungal disease encountered in dermatology, most commonly caused by an overgrowth of Candida albicans in the mouth. Although thrush is a well-recognized presentation of OC, it behooves clinicians to be aware of the many other presentations of this disease and how to accurately diagnose and manage these cases. The clinical presentations of OC can be broadly classified as white or erythematous candidiasis, with various subtypes in each category. The treatments include appropriate oral hygiene, topical agents, and systemic medications. This review focuses on the various clinical presentations of OC and treatment options. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Oral myiasis

    Treville Pereira

    2010-01-01

    Full Text Available Myiasis is a relatively rare condition arising from the invasion of body tissues or cavities of living animals or humans by maggots or larvae of certain species of flies. It is an uncommon clinical condition, being more frequent in underdeveloped countries and hot climate regions, and is associated with poor hygiene, suppurative oral lesions; alcoholism and senility. Its diagnosis is made basically by the presence of larvae. The present article reports a case of oral myiasis involving 20 larvae in a patient with neurological deficiency.

  14. Analysis of electron interactions in dielectric gases

    Olivet, Aurelio; Duque, Daniel; Vega, Lourdes F.

    2007-01-01

    We present and discuss results concerning electron interactions processes of dielectric gases and their relationship with the macroscopic behavior of these gases, in particular, with their dielectric strength. Such analysis is based on calculating energies of reactions for molecular ionization, dissociative ionization, parent negative ion formation, and dissociative electron attachment processes. We hypothesize that the estimation of the required energy for a reduced number of processes that take place in electrically stressed gases could be related to the gas' capability to manage the electron flow during an electrical discharge. All calculations were done with semiempirical quantum chemistry methods, including an initial optimization of molecular geometry and heat of formation of the dielectric gases and all of species that appear during electron interaction reactions. The performance of semiempirical methods Austin model 1 and Parametric model 3 (PM3) was compared for several compounds, PM3 being superior in most cases. Calculations performed for a sample of nine dielectric gases show that electron attachment and detachment processes occur in different energy bands that do not overlap for any value of the dielectric strength. We have also analyzed the relationship between dielectric strength and two physical properties: electron affinity and ionization energy. Calculations performed for 43 dielectric gases show no clear correlation between them, although certain guidelines for the qualitative estimation of dielectric strength can still be assessed

  15. Gases and carbon in metals. Pt. 14

    Jehn, H.; Speck, H.; Hehn, W.; Fromm, E.; Hoerz, G.

    1981-01-01

    This issue is part of a series of data on 'Gases and Carbon in Metals' which supplements the data compilation in the book 'Gase und Kohlenstoff in Metallen' (Gases and Carbon in Metals), edited by E. Fromm and E. Gebhardt, Springer-Verlag, Berlin 1976. The present survey includes results from papers published after the copy deadline and recommends critically selected data. Furthermore, it comprises a bibliography of relevant literature. For each element, firstly data on binary systems are presented, starting with hydrogen and followed by carbon, nitrogen, oxygen, and rare gases. Within one metal-metalloid system the data are listed under topics such as solubility, solubility limit, dissociation pressure of compounds, vapour pressure of volatile oxides, thermodynamic data, diffusion, transport parameters (effective valence, heat of transport), permeation of gases through metals, gas absorption and gas desorption kinetics, compound formation kinetics, precipitation kinetics, and property changes. Following the data on binary systems, the data of ternary systems are presented, beginning with systems which contain one metal and two gases or one gas and carbon and continuing with systems with two metals and one gas or carbon. (orig./GE)

  16. Oral calcitonin

    Hamdy RC

    2012-09-01

    Full Text Available Ronald C Hamdy,1,2 Dane N Daley11Osteoporosis Center, College of Medicine, East Tennessee State University, 2Veterans Affairs Medical Center, Johnson City, TN, USAAbstract: Calcitonin is a hormone secreted by the C-cells of the thyroid gland in response to elevations of the plasma calcium level. It reduces bone resorption by inhibiting mature active osteoclasts and increases renal calcium excretion. It is used in the management of postmenopausal osteoporosis, Paget's disease of bone, and malignancy-associated hypercalcemia. Synthetic and recombinant calcitonin preparations are available; both have similar pharmacokinetic and pharmacodynamic profiles. As calcitonin is a peptide, the traditional method of administration has been parenteral or intranasal. This hinders its clinical use: adherence with therapy is notoriously low, and withdrawal from clinical trials has been problematic. An oral formulation would be more attractive, practical, and convenient to patients. In addition to its effect on active osteoclasts and renal tubules, calcitonin has an analgesic action, possibly mediated through β-endorphins and the central modulation of pain perception. It also exerts a protective action on cartilage and may be useful in the management of osteoarthritis and possibly rheumatoid arthritis. Oral formulations of calcitonin have been developed using different techniques. The most studied involves drug-delivery carriers such as Eligen® 8-(N-2hydroxy-5-chloro-benzoyl-amino-caprylic acid (5-CNAC (Emisphere Technologies, Cedar Knolls, NJ. Several factors affect the bioavailability and efficacy of orally administered calcitonin, including amount of water used to take the tablet, time of day the tablet is taken, and proximity to intake of a meal. Preliminary results looked promising. Unfortunately, in two Phase III studies, oral calcitonin (0.8 mg with 200 mg 5-CNAC, once a day for postmenopausal osteoporosis and twice a day for osteoarthritis failed to

  17. Oral care.

    Hitz Lindenmüller, Irène; Lambrecht, J Thomas

    2011-01-01

    Adequate dental and oral hygiene may become a challenge for all users and especially for elderly people and young children because of their limited motor skills. The same holds true for patients undergoing/recovering from chemo-/radiotherapy with accompanying sensitive mucosal conditions. Poor dental hygiene can result in tooth decay, gingivitis, periodontitis, tooth loss, bad breath (halitosis), fungal infection and gum diseases. The use of a toothbrush is the most important measure for oral hygiene. Toothbrushes with soft bristles operated carefully by hand or via an electric device help to remove plaque and to avoid mucosal trauma. A handlebar with a grip cover can be helpful for manually disabled patients or for those with reduced motor skills. In case of oral hygiene at the bedside or of patients during/after chemo-/radiotherapy a gauze pad can be helpful for gently cleaning the teeth, gums and tongue. The use of fluoride toothpaste is imperative for the daily oral hygiene. Detergents such as sodium lauryl sulphate improve the cleaning action but may also dehydrate and irritate the mucous membrane. The use of products containing detergents and flavouring agents (peppermint, menthol, cinnamon) should therefore be avoided by bedridden patients or those with dry mouth and sensitive mucosa. Aids for suitable interdental cleaning, such as dental floss, interdental brushes or dental sticks, are often complicated to operate. Their correct use should be instructed by healthcare professionals. To support dental care, additional fluoridation with a fluoride gel or rinse can be useful. Products further containing antiseptics such as chlorhexidine or triclosan reduce the quantity of bacteria in the mouth. For patients undergoing or having undergone radio-/chemotherapy, a mouthwash that concomitantly moisturizes the oral mucosa is advisable. Copyright © 2011 S. Karger AG, Basel.

  18. Oral Health and Aging

    ... please turn JavaScript on. Feature: Oral Health and Aging Oral Health and Aging Past Issues / Summer 2016 Table of Contents Jerrold ... they may need. Read More "Oral Health and Aging" Articles Oral Health and Aging / 4 Myths About ...

  19. Shale gases, a windfall for France?

    Tonnac, Alain de; Perves, Jean-Pierre

    2013-11-01

    After having recalled the definition and origin of shale gases, the different non conventional gases and their exploitation techniques (hydraulic fracturing and horizontal drilling) this report examines whether these gases are an opportunity for France. Some characteristics and data of the fossil and gas markets are presented and commented: world primary energy consumption, proved reserves of non conventional gases and their locations, European regions which may possess reserves of shale gases and coal-bed methane, origins of gas imports in France. The second part addresses shale gas deposits and their exploitation: discussion of the influence of the various rock parameters, evolution of production. The third part discusses the exploitation techniques and specific drilling tools. The issue of exploitation safety and security is addressed as well as the associated controversies: about the pollution of underground waters, about the fact that deep drillings result in pollution, about the risks associated with hydraulic fracturing and injections of chemical products, about the hold on ground and site degradation, about water consumption, about pollution due to gas pipeline leakage, about seismic risk, about noise drawbacks, about risks for health, about exploration and production authorization and license, and about air pollution and climate. The last part addresses the French situation and its future: status of the energy bill, recommendations made by a previous government, cancellation of authorizations, etc. Other information are provided in appendix about non conventional hydrocarbons, about shale gas exploitation in the USA, and about the Lacq gas

  20. Bose-Einstein condensation of atomic gases

    Anglin, J. R.; Ketterle, W.

    2003-01-01

    The early experiments on Bose-Einstein condensation in dilute atomic gases accomplished three longstanding goals. First, cooling of neutral atoms into their motional state, thus subjecting them to ultimate control, limited only by Heisenberg uncertainty relation. Second, creation of a coherent sample of atoms, in which all occupy the same quantum states, and the realization of atom lasers - devices that output coherent matter waves. And third, creation of gaseous quantum fluid, with properties that are different from the quantum liquids helium-3 and helium-4. The field of Bose-Einstein condensation of atomic gases has continued to progress rapidly, driven by the combination of new experimental techniques and theoretical advances. The family of quantum degenerate gases has grown, and now includes metastable and fermionic atoms. condensates have become an ultralow-temperature laboratory for atom optics, collisional physics and many-body physics, encompassing phonons, superfluidity, quantized vortices, Josephson junctions and quantum phase transitions. (author)

  1. Density Fluctuations in Uniform Quantum Gases

    Bosse, J.; Pathak, K. N.; Singh, G. S.

    2011-01-01

    Analytical expressions are given for the static structure factor S(k) and the pair correlation function g(r) for uniform ideal Bose-Einstein and Fermi-Dirac gases for all temperatures. In the vicinity of Bose Einstein condensation (BEC) temperature, g(r) becomes long ranged and remains so in the condensed phase. In the dilute gas limit, g(r) of bosons and fermions do not coincide with Maxwell-Boltzmann gas but exhibit bunching and anti-bunching effect respectively. The width of these functions depends on the temperature and is scaled as √(inverse atomic mass). Our numerical results provide the precise quantitative values of suppression/increase (antibunching and bunching) of the density fluctuations at small distances in ideal quantum gases in qualitative agreement with the experimental observation for almost non-trapped dilute gases.

  2. Method of processing radioactive rare gase

    Tagusagawa, Atsushi; Tuda, Kazuaki.

    1988-01-01

    Purpose: To obtain a safety processing method without using mechanical pumps or pressure-proof containers and, accordingly, with no risk for the leakage of radioactive rare gas. Method: A container filled with zeolige is inserted with a cover being opened into an autoclave. Meanwhile, krypton-containing gases are supplied to an adsorption tower filled with adsorbents, cooled, adsorbed and then heated to desorb adsorbed krypton. The krypton-containing gases are introduced due to the pressure difference to the autoclave thereby causing krypton to adsorb at ambient temperature to zeolite. Then, the inside of the autoclave is heated to desorb krypton and adsorbed moistures from zeolite and the pressure is elevated. After sending the gases under pressure to the adsorption tower, the zeolite-filled container is taken out from the autoclave, tightly closed and then transferred to a predetermined site. (Takahashi, M.)

  3. GREENHOUSE GASES AND MEANS OF PREVENTION

    Dušica Stojanović

    2013-09-01

    Full Text Available The greenhouse effect can be defined as the consequence of increased heating of the Earth's surface, as well as the lower atmosphere by carbon dioxide, water vapor, and other trace amounts gases. It is well-known that human industrial activities have released large amounts of greenhouse gases in the atmosphere, about 900 billion tons of carbon dioxide, and it is estimated that up to 450 billion are still in the atmosphere. In comparison to greenhouse gases water vapor is one of the greatest contributors to the greenhouse effect on Earth. Many projects, as does the PURGE project, have tendences to build on the already conducted research and to quantify the positive and negative impacts on health and wellbeing of the population with greenhouse gas reduction strategies that are curently being implemented and should be increasingly applied in various sectors and urban areas, having offices in Europe, China and India.

  4. Dark lump excitations in superfluid Fermi gases

    Xu, Yan-Xia; Duan, Wen-Shan

    2012-11-01

    We study the linear and nonlinear properties of two-dimensional matter-wave pulses in disk-shaped superfluid Fermi gases. A Kadomtsev—Petviashvili I (KPI) solitary wave has been realized for superfluid Fermi gases in the limited cases of Bardeen—Cooper—Schrieffer (BCS) regime, Bose—Einstein condensate (BEC) regime, and unitarity regime. One-lump solution as well as one-line soliton solutions for the KPI equation are obtained, and two-line soliton solutions with the same amplitude are also studied in the limited cases. The dependence of the lump propagating velocity and the sound speed of two-dimensional superfluid Fermi gases on the interaction parameter are investigated for the limited cases of BEC and unitarity.

  5. Dark lump excitations in superfluid Fermi gases

    Xu Yan-Xia; Duan Wen-Shan

    2012-01-01

    We study the linear and nonlinear properties of two-dimensional matter-wave pulses in disk-shaped superfluid Fermi gases. A Kadomtsev—Petviashvili I (KPI) solitary wave has been realized for superfluid Fermi gases in the limited cases of Bardeen—Cooper—Schrieffer (BCS) regime, Bose—Einstein condensate (BEC) regime, and unitarity regime. One-lump solution as well as one-line soliton solutions for the KPI equation are obtained, and two-line soliton solutions with the same amplitude are also studied in the limited cases. The dependence of the lump propagating velocity and the sound speed of two-dimensional superfluid Fermi gases on the interaction parameter are investigated for the limited cases of BEC and unitarity

  6. Gases and vacua handbook of vacuum physics

    Beck, A H

    2013-01-01

    Handbook of Vacuum Physics, Volume 1: Gases and Vacua presents three major topics, which are the fourth to sixth parts of this volume. These topics are the remarks on units of physical quantities; kinetic theory of gases and gaseous flow; and theory of vacuum diffusion pumps. The first topic aims to present concisely the significance of units of physical quantities, catering the need and interest of those who take measurements and make calculations in different fields of vacuum sciences. The technique and applications of this particular topic are also provided. The second main topic focuses sp

  7. Measuring Viscosities of Gases at Atmospheric Pressure

    Singh, Jag J.; Mall, Gerald H.; Hoshang, Chegini

    1987-01-01

    Variant of general capillary method for measuring viscosities of unknown gases based on use of thermal mass-flowmeter section for direct measurement of pressure drops. In technique, flowmeter serves dual role, providing data for determining volume flow rates and serving as well-characterized capillary-tube section for measurement of differential pressures across it. New method simple, sensitive, and adaptable for absolute or relative viscosity measurements of low-pressure gases. Suited for very complex hydrocarbon mixtures where limitations of classical theory and compositional errors make theoretical calculations less reliable.

  8. Origins of geothermal gases at Yellowstone

    Lowenstern, Jacob B.; Bergfeld, Deborah; Evans, William C.; Hunt, Andrew G.

    2015-01-01

    Gas emissions at the Yellowstone Plateau Volcanic Field (YPVF) reflect open-system mixing of gas species originating from diverse rock types, magmas, and crustal fluids, all combined in varying proportions at different thermal areas. Gases are not necessarily in chemical equilibrium with the waters through which they vent, especially in acid sulfate terrain where bubbles stream through stagnant acid water. Gases in adjacent thermal areas often can be differentiated by isotopic and gas ratios, and cannot be tied to one another solely by shallow processes such as boiling-induced fractionation of a parent liquid. Instead, they inherit unique gas ratios (e.g., CH4/He) from the dominant rock reservoirs where they originate, some of which underlie the Quaternary volcanic rocks. Steam/gas ratios (essentially H2O/CO2) of Yellowstone fumaroles correlate with Ar/He and N2/CO2, strongly suggesting that H2O/CO2 is controlled by addition of steam boiled from water rich in atmospheric gases. Moreover, H2O/CO2 varies systematically with geographic location, such that boiling is more enhanced in some areas than others. The δ13C and 3He/CO2 of gases reflect a dominant mantle origin for CO2 in Yellowstone gas. The mantle signature is most evident at Mud Volcano, which hosts gases with the lowest H2O/CO2, lowest CH4 concentrations and highest He isotope ratios (~16Ra), consistent with either a young subsurface intrusion or less input of crustal and meteoric gas than any other location at Yellowstone. Across the YPVF, He isotope ratios (3He/4He) inversely vary with He concentrations, and reflect varied amounts of long- stored, radiogenic He added to the magmatic endmember within the crust. Similarly, addition of CH4 from organic-rich sediments is common in the eastern thermal areas at Yellowstone. Overall, Yellowstone gases reflect addition of deep, high-temperature magmatic gas (CO2-rich), lower-temperatures crustal gases (4He- and CH4-bearing), and those gases (N2, Ne, Ar) added

  9. Itinerant Ferromagnetism in Ultracold Fermi Gases

    Heiselberg, Henning

    2012-01-01

    Itinerant ferromagnetism in cold Fermi gases with repulsive interactions is studied applying the Jastrow-Slater approximation generalized to finite polarization and temperature. For two components at zero temperature a second order transition is found at akF ≃ 0.90 compatible with QMC. Thermodyna......Itinerant ferromagnetism in cold Fermi gases with repulsive interactions is studied applying the Jastrow-Slater approximation generalized to finite polarization and temperature. For two components at zero temperature a second order transition is found at akF ≃ 0.90 compatible with QMC...

  10. Flammability characteristics of combustible gases and vapors

    Zabetakis, M. G. [Bureau of Mines, Pittsburgh, PA (United States)

    1964-05-01

    This is a summary of the available limit of flammability, autoignition and burning-rate data for more than 200 combustible gases and vapors in air and other oxidants, as well as of empirical rules and graphs that can be used to predict similar data for thousands of other combustibles under a variety of environmental conditions. Spec$c data are presented on the paraffinic, unsaturated, aromatic, and alicyclic hydrocarbons, alcohols, ethers, aldehydes, ketones, and sulfur compounds, and an assortment of fuels, fuel blends, hydraulic fluids, engine oils, and miscellaneous combustible gases and vapors.

  11. Investigations into electrical discharges in gases

    Klyarfel'D, B N

    2013-01-01

    Investigations into Electrical Discharges in Gases is a compilation of scientific articles that covers the advances in the investigation of the fundamental processes occurring in electrical discharges in gases and vapors. The book details the different aspects of the whole life cycle of an arc, which include the initiation of a discharge, its transition into an arc, the lateral spread of the arc column, and the recovery of electric strength after extinction of an arc. The text also discusses the methods for the dynamic measurement of vapor density in the vicinity of electrical discharges, alon

  12. Nanoclusters and Microparticles in Gases and Vapors

    Smirnov, Boris M

    2012-01-01

    Research of processes involving Nanoclusters and Microparticleshas been developing fastin many fields of rescent research, in particular in materials science. To stay at the cutting edge of this development, a sound understanding of the processes is needed. In this work, several processes involving small particles are described, such as transport processes in gases, charging of small particles in gases, chemical processes, atom attachment and quenching of excited atomic particles on surfaces, nucleation, coagulation, coalescence and growth processes for particles and aggregates. This work pres

  13. Indoor air pollution caused by geothermal gases

    Durand, Michael

    2006-01-01

    This paper discusses the little-known but potentially serious indoor air quality problems that may occur where buildings are constructed on geothermal ground. The main problems are related to seepage of carbon dioxide, hydrogen sulphide, radon and other gases from soil cavities directly into indoor air through perforations in the structure. These gases present a health hazard, and hydrogen sulphide, which is particularly corrosive, may cause problems electrical and electronic systems. Counter-measures are not always effective, so developments in such areas should only be undertaken with a clear understanding of site-specific issues and their possible solutions. (author)

  14. Ultracold Dipolar Gases in Optical Lattices

    Trefzger, C.; Menotti, C.; Capogrosso-Sansone, B.; Lewenstein, M.

    2011-01-01

    This tutorial is a theoretical work, in which we study the physics of ultra-cold dipolar bosonic gases in optical lattices. Such gases consist of bosonic atoms or molecules that interact via dipolar forces, and that are cooled below the quantum degeneracy temperature, typically in the nK range. When such a degenerate quantum gas is loaded into an optical lattice produced by standing waves of laser light, new kinds of physical phenomena occur. These systems realize then extended Hubbard-type m...

  15. Fate of Gases generated from Nuclear Wastes

    Srinivasulu, M.; Francis, A. J. [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of); Francis, A. J. [Brookhaven National Laboratory, New York (United States)

    2013-05-15

    The backfill materials such as cement, bentonite or crushed rock are used as engineered barriers against groundwater infiltration and radionuclide transport. Gas generation from radioactive wastes is attributed to radiolysis, corrosion of metals, and degradation of organic materials. Corrosion of steel drums and biodegradation of organic materials in L/ILW can generate gas which causes pressure build up and has the potential to compromise the integrity of waste containers and release the radionuclides and other contaminants into the environment. Performance assessment therefore requires a detailed understanding of the source and fate of gas generation and transport within the disposal system. Here we review the sources and fate of various type of gases generated from nuclear wastes and repositories. Studies on modeling of the fate and transport of repository gases primarily deal with hydrogen and CO{sub 2}. Although hydrogen and carbon dioxide are the major gases of concern, microbial transformations of these gases in the subterranean environments could be significant. Metabolism of hydrogen along with the carbon dioxide results in the formation of methane, low molecular weight organic compounds and cell biomass and thus could affect the total inventory in a repository environment. Modeling studies should take into consideration of both the gas generation and consumption processes over the long-term.

  16. Electron-Atom Collisions in Gases

    Kraftmakher, Yaakov

    2013-01-01

    Electron-atom collisions in gases are an aspect of atomic physics. Three experiments in this field employing a thyratron are described: (i) the Ramsauer-Townsend effect, (ii) the excitation and ionization potentials of xenon and (iii) the ion-electron recombination after interrupting the electric discharge.

  17. Acid dew point measurement in flue gases

    Struschka, M.; Baumbach, G.

    1986-06-01

    The operation of modern boiler plants requires the continuous measurement of the acid dew point in flue gases. An existing measuring instrument was modified in such a way that it can determine acid dew points reliably, reproduceably and continuously. The authors present the mechanisms of the dew point formation, the dew point measuring principle, the modification and the operational results.

  18. Properties and Bibliography of GaSe

    1994-02-01

    Musaev, A. E. Bakhyshev, N. M. Gasanly and L. G. Musaeva . (1975). "Anisotropy of the optical constants of GaS and GaSe near the absorption edge." Sov...Phys. Semiconductors. 9 94-95 Russian ref.: Fiz. Tekh. Poluprovodn. 9 142-145 (January 1975). Akhundov, G. A., L. G. Musaeva and M. D. Khomutova

  19. Mitigation of greenhouse gases from agriculture

    Schils, R.L.M.; Ellis, J. L.; de Klein, C. A. M.

    2013-01-01

    Models are widely used to simulate the emission of greenhouse gases (GHG). They help to identify knowledge gaps, estimate total emissions for inventories, develop mitigation options and policies, raise awareness and encourage adoption. These models vary in scale, scope and methodological approach...

  20. Noble gases as cardioprotectants - translatability and mechanism

    Smit, Kirsten F.; Weber, Nina C.; Hollmann, Markus W.; Preckel, Benedikt

    2015-01-01

    Several noble gases, although classified as inert substances, exert a tissue-protective effect in different experimental models when applied before organ ischaemia as an early or late preconditioning stimulus, after ischaemia as a post-conditioning stimulus or when given in combination before,

  1. Toxicity of pyrolysis gases from polyether sulfone

    Hilado, C. J.; Olcomendy, E. M.

    1979-01-01

    A sample of polyether sulfone was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. Animal response times were relatively short at pyrolysis temperatures of 600 to 800 C, with death occurring within 6 min. The principal toxicant appeared to be a compound other than carbon monoxide.

  2. Anaesthetic gases: environmental impact and alternatives ...

    Anaesthetic gases: environmental impact and alternatives. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... to be small when compared to gaseous emissions from industrial and agricultural sources, the actual percentage contribution to climate change is small. ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  3. Cold quantum gases with resonant interactions

    Marcelis, B.

    2008-01-01

    We study ultracold gases of alkali-metal atoms in the quantum degenerate regime. The interatomic interactions in these type of systems can be tuned using resonances induced by magnetic or electric fields. The tunability of the interactions, together with the possibility of confining the atoms with

  4. Teacher's Guide for Balloons and Gases.

    Griffith, Joe H.; And Others

    This guide was developed to provide children with an opportunity to prepare and collect several common gases and to discover and work with some of their properties. The guide is divided into five major sections: (1) introduction, (2) materials, (3) activities, (4) balloons aloft, and (5) an appendix. The introduction provides information…

  5. Prediction of friction coefficients for gases

    Taylor, M. F.

    1969-01-01

    Empirical relations are used for correlating laminar and turbulent friction coefficients for gases, with large variations in the physical properties, flowing through smooth tubes. These relations have been used to correlate friction coefficients for hydrogen, helium, nitrogen, carbon dioxide and air.

  6. Plant for removing radioactive rare gases

    An, Buzai; Kanazawa, Toshio

    1977-01-01

    The outline of the pilot plant to remove and recover radioactive rare gases generated from nuclear power plants, reprocessing installations for nuclear fuel, nuclear research installations, etc. is described below. Among the studies of various processes such as liquefaction and distillation, absorption into solvents, active carbon adsorption, diaphragm method, etc., the liquefaction and distillation process by rectification at low temperature has been positively developed. It is in the stage of practical application for removing rare gases in waste gases from reprocessing and nuclear power plants. This is the process with high safety and excellent rare gas removing capability. Further research and development have been also made for selective adsorption and desorption method at low temperature which is very efficient as there is no release of long life nuclides such as Krypton-85. Rare gases recovered by the above mentioned removal systems must be stored safely for a long time as their half lives are long and specific radioactivities are high. The study has been made continuously on the storage methods including adsorption in cylinders and remotely automatically sealing storing system. (Kobatake, H.)

  7. Head, Neck, and Oral Cancer

    Full Text Available ... Extractions and Other Oral Surgeries Extractions and Other Oral Surgeries Oral and maxillofacial surgeons surgically treat the soft ... Extractions and Other Oral Surgeries Extractions and Other Oral Surgeries Oral and maxillofacial surgeons surgically treat the soft ...

  8. Purification of burned gases of domestic wastes; Moderna purificacion de gases quemados de las basuras domesticas

    Gottschalk, J.; Buttman, P.; Johansson, T.

    1997-09-01

    The author presents the technology to reduce the emission from the burned gases purification of domestic wastes combustion. The technology was demonstrated in Hobec, Denmark, and developed in Germany. (Author)

  9. Towards understanding oral health

    Zaura, E.; ten Cate, J.M.

    2015-01-01

    During the last century, dental research has focused on unraveling the mechanisms behind various oral pathologies, while oral health was typically described as the mere absence of oral diseases. The term ‘oral microbial homeostasis' is used to describe the capacity of the oral ecosystem to maintain

  10. Oral dirofilariasis

    Mahija Janardhanan

    2014-01-01

    Full Text Available Filariasis affecting animals can rarely cause infections in human beings through the accidental bite of potential vectors. The resulting infection in man, known as zoonotic filariasis occur worldwide. Human dirofilariasis, the most common zoonotic filariasis, is caused by the filarial worm belonging to the genus Dirofilaria. Dirofilarial worms, which are recognized as pathogenic in man can cause nodular lesions in the lung, subcutaneous tissue, peritoneal cavity or eyes. Oral dirofilariasis is extremely rare and only a few cases have been documented. We report an interesting case of dirofilariasis due to Dirofilaria repens involving buccal mucosa in a patient who presented with a facial swelling. The clinical features, diagnostic issues and treatment aspects are discussed. This paper stresses the importance of considering dirofilariasis as differential diagnosis for subcutaneous swelling of the face, especially in areas where it is endemic.

  11. Oral dirofilariasis.

    Janardhanan, Mahija; Rakesh, S; Savithri, Vindhya

    2014-01-01

    Filariasis affecting animals can rarely cause infections in human beings through the accidental bite of potential vectors. The resulting infection in man, known as zoonotic filariasis occur worldwide. Human dirofilariasis, the most common zoonotic filariasis, is caused by the filarial worm belonging to the genus Dirofilaria. Dirofilarial worms, which are recognized as pathogenic in man can cause nodular lesions in the lung, subcutaneous tissue, peritoneal cavity or eyes. Oral dirofilariasis is extremely rare and only a few cases have been documented. We report an interesting case of dirofilariasis due to Dirofilaria repens involving buccal mucosa in a patient who presented with a facial swelling. The clinical features, diagnostic issues and treatment aspects are discussed. This paper stresses the importance of considering dirofilariasis as differential diagnosis for subcutaneous swelling of the face, especially in areas where it is endemic.

  12. Oral sex, oral health and orogenital infections

    Rajiv Saini

    2010-01-01

    Full Text Available Oral sex is commonly practiced by sexually active male-female and same-gender couples of various ages, including adolescents. The various type of oral sex practices are fellatio, cunnilingus and analingus. Oral sex is infrequently examined in research on adolescents; oral sex can transmit oral, respiratory, and genital pathogens. Oral health has a direct impact on the transmission of infection; a cut in your mouth, bleeding gums, lip sores or broken skin increases chances of infection. Although oral sex is considered a low risk activity, it is important to use protection and safer sex precautions. There are various methods of preventing infection during oral sex such as physical barriers, health and medical issues, ethical issues and oral hygiene and dental issues. The lesions or unhealthy periodontal status of oral cavity accelerates the phenomenon of transmission of infections into the circulation. Thus consequences of unhealthy or painful oral cavity are significant and oral health should be given paramount importance for the practice of oral sex.

  13. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  14. 75 FR 57669 - Mandatory Reporting of Greenhouse Gases

    2010-09-22

    ... Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action amends the Final Mandatory Reporting of Greenhouse Gases Rule to require reporters... Numbers GHG greenhouse gas GHGRP Greenhouse Gas Reporting Program HCFC hydrochlorofluorocarbon HFC...

  15. Geodesics in thermodynamic state spaces of quantum gases

    Oshima, H.; Obata, T.; Hara, H.

    2002-01-01

    The geodesics for ideal quantum gases are numerically studied. We show that 30 ideal quantum state is connected to an ideal classical state by geodesics and that the bundle of geodesics for Bose gases have a tendency of convergence

  16. Radiolytic generation of gases in reactors

    Ramshesh, V.; Venkateswarlu, K.S.

    1988-01-01

    Water or heavy water is used in different circuits in a reactor. Their most common use is as a moderator and/or as a coolant. Light water is used at other places such as in end shield, calandria vault etc., In the process they are exposed to intense ionizing radiation and undergo radiolytic degradation. The molecular produts of radiolysis are hydrogen, hydrogen peroxide and oxygen. As is commonly known if hydrogen is formed beyond a certain level, in the presence of oxygen it may lead to combustion or even explosion. Thus one should comprehend the basic principles of radiolysis and see whether the concentration of these gases under various conditions can be worked out. This report attempts to analyse in depth the radiolytic generation of gases in reactor systems. (author). 3 tabs

  17. Simulation of diffusion in concentrated lattice gases

    Kehr, K.W.

    1986-01-01

    Recently the diffusion of particles in lattice gases was studied extensively by theoretical methods and numerical simulations. This paper reviews work on collective and, in particular, on tracer diffusion. The diffusion of tagged particles is characterized by a correlation factor whose behavior as a function of concentration is now well understood. Also the detailed kinetics of the tracer transitions was investigated. A special case is the one-dimensional lattice gas where the tracer diffusion coefficient vanishes. An interesting extension is the case of tagged atoms with a different transition rate. This model allows to study various physical situations, including impurity diffusion, percolation, and diffusion in partially blocked lattices. Finally some recent work on diffusion in lattice gases under the influence of a drift field will be reported. (author)

  18. Functional renormalization and ultracold quantum gases

    Floerchinger, Stefan

    2010-01-01

    Modern techniques from quantum field theory are applied in this work to the description of ultracold quantum gases. This leads to a unified description of many phenomena including superfluidity for bosons and fermions, classical and quantum phase transitions, different dimensions, thermodynamic properties and few-body phenomena as bound state formation or the Efimov effect. The non-perturbative treatment with renormalization group flow equations can account for all known limiting cases by solving one single equation. It improves previous results quantitatively and brings qualitatively new insights. As an example, new quantum phase transitions are found for fermions with three spin states. Ultracold atomic gases can be seen as an interesting model for features of high energy physics and for condensed matter theory. The research reported in this thesis helps to solve the difficult complexity problem in modern theoretical physics. (orig.)

  19. Properties of quantum self-gravitating gases

    Rumyantseva, E.N.

    1981-01-01

    Ways of development of the quantum field theory in the general relativity theory are under consideration. A direction, where consideration of quantum fields in strong nonstatic gravitational fields leads to such effects as particle production, is found out. Authors managed to explain properties of quantum self-gravitating gases on the base of an expansion the fugacity in power series for bose- and fermi gases. Expressions for fluctuations in statistical models of the Fridmann universe are presented. The spectrum density of relict neutrinos in Fridmann models is calculated. A characteristic low boundary of the neutrino energy spectrum constitutes 1 MeV. A number of neutrinos with such energies practically is equal to zero. A great number of neutrinos has energies 0 . It is precisely these neurinos, which are responsible for the closed state of the universe according to the built up model

  20. Detecting Friedel oscillations in ultracold Fermi gases

    Riechers, Keno; Hueck, Klaus; Luick, Niclas; Lompe, Thomas; Moritz, Henning

    2017-09-01

    Investigating Friedel oscillations in ultracold gases would complement the studies performed on solid state samples with scanning-tunneling microscopes. In atomic quantum gases interactions and external potentials can be tuned freely and the inherently slower dynamics allow to access non-equilibrium dynamics following a potential or interaction quench. Here, we examine how Friedel oscillations can be observed in current ultracold gas experiments under realistic conditions. To this aim we numerically calculate the amplitude of the Friedel oscillations which are induced by a potential barrier in a 1D Fermi gas and compare it to the expected atomic and photonic shot noise in a density measurement. We find that to detect Friedel oscillations the signal from several thousand one-dimensional systems has to be averaged. However, as up to 100 parallel one-dimensional systems can be prepared in a single run with present experiments, averaging over about 100 images is sufficient.

  1. Two-Dimensional Homogeneous Fermi Gases

    Hueck, Klaus; Luick, Niclas; Sobirey, Lennart; Siegl, Jonas; Lompe, Thomas; Moritz, Henning

    2018-02-01

    We report on the experimental realization of homogeneous two-dimensional (2D) Fermi gases trapped in a box potential. In contrast to harmonically trapped gases, these homogeneous 2D systems are ideally suited to probe local as well as nonlocal properties of strongly interacting many-body systems. As a first benchmark experiment, we use a local probe to measure the density of a noninteracting 2D Fermi gas as a function of the chemical potential and find excellent agreement with the corresponding equation of state. We then perform matter wave focusing to extract the momentum distribution of the system and directly observe Pauli blocking in a near unity occupation of momentum states. Finally, we measure the momentum distribution of an interacting homogeneous 2D gas in the crossover between attractively interacting fermions and bosonic dimers.

  2. Comparing greenhouse gases for policy purposes

    Schmalensee, R.

    1993-01-01

    In order to derive optimal policies for greenhouse gas emissions control, the discounted marginal damages of emissions from different gases must be compared. The greenhouse warming potential (GWP) index, which is most often used to compare greenhouse gases, is not based on such a damage comparison. This essay presents assumptions under which ratios of gas-specific discounted marginal damages reduce to ratios of discounted marginal contributions to radiative forcing, where the discount rate is the difference between the discount rate relevant to climate-related damages and the rate of growth of marginal climate-related damages over time. If there are important gas-specific costs or benefits not tied to radiative forcing, however, such as direct effects of carbon dioxide on plant growth, there is in general no shortcut around explicit comparison of discounted net marginal damages. 16 refs

  3. Oxygen partial pressure sensor for gases

    Barbero, J.A.; Azcona, M.A.; Orce, A.

    1997-01-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10 -6 -1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs

  4. Oxygen partial pressure sensor for gases

    Barbero, J.A.; Azcona, M.A.; Orce, A. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1997-10-01

    Precise measurement of very low oxygen partial pressure is important in both laboratories and industries. Particularly in nuclear industry, it is relevant in the different steps of the nuclear fuel fabrication. It is presented an instrument which is handy and of easy construction, suitable for the measurement of oxygen partial pressure of gases, in the range of 10{sup -6}-1 atm. It is based on a solid electrolyte galvanic cell, using Yttria doped zirconia as a ceramic membrane. Through an indirect measurement and calibration, the instrument can be used to measure the content of free oxygen in liquids. It is a import feature in NPP instrumentation. The equipment was calibrated with mixtures of special nonreactive gases. (author). 5 refs.

  5. Method for enhancing microbial utilization rates of gases using perfluorocarbons

    Turick, C.E.

    1997-06-10

    A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases. 3 figs.

  6. Role of buffer gases in optoacoustic spectroscopy

    Thomas III, L.J.; Kelly, M.J.; Amer, N.M.

    1978-01-01

    The dependence of an acoustically resonant optoacoustic signal on the molecular weight and thermodynamic and transport properpties of the buffer gas is reported. Our results show that careful selection of such gases can significantly increase the sensitivity and flexibility of optoacoustic spectroscopy. We also demonstrate that such thermodynamic quantities as γ (equivalentC/sub p//C/sub v/) and sound velocity can now be measured readily and accurately. Other potential applications are suggested

  7. Splitting of inviscid fluxes for real gases

    Liou, Meng-Sing; Van Leer, Bram; Shuen, Jian-Shun

    1990-01-01

    Flux-vector and flux-difference splittings for the inviscid terms of the compressible flow equations are derived under the assumption of a general equation of state for a real gas in equilibrium. No necessary assumptions, approximations for auxiliary quantities are introduced. The formulas derived include several particular cases known for ideal gases and readily apply to curvilinear coordinates. Applications of the formulas in a TVD algorithm to one-dimensional shock-tube and nozzle problems show their quality and robustness.

  8. The Osher scheme for real gases

    Suresh, Ambady; Liou, Meng-Sing

    1990-01-01

    An extension of Osher's approximate Riemann solver to include gases with an arbitrary equation of state is presented. By a judicious choice of thermodynamic variables, the Riemann invariats are reduced to quadratures which are then approximated numerically. The extension is rigorous and does not involve any further assumptions or approximations over the ideal gas case. Numerical results are presented to demonstrate the feasibility and accuracy of the proposed method.

  9. Effect of Greenhouse Gases Dissolved in Seawater.

    Matsunaga, Shigeki

    2015-12-30

    A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.

  10. Paschen's law studies in cold gases

    Massarczyk, R.; Chu, P.; Elliott, S. R.; Rielage, K.; Dugger, C.; Xu, W.

    2016-01-01

    The break-through voltage over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. The breakthrough behavior of the fill gas in colder environments was tested as well. A significant shift of the curve relative to the results at room temperature was observed. The results can be explained by combining Paschen's law and the ideal gas law.

  11. Paschen's law studies in cold gases

    Massarczyk, R.; Chu, P.; Dugger, C.; Elliott, S. R.; Rielage, K.; Xu, W.

    2017-06-01

    The break-through voltage behavior over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. At lower temperatures, a significant shift of the curve relative to the results at room temperature was observed. This behavior can be explained by combining Paschen's law and the ideal gas law.

  12. Paschen's law studies in cold gases

    Massarczyk, R.; Chu, P.; Elliott, S.R.; Rielage, K.; Xu, W.; Dugger, C.

    2017-01-01

    The break-through voltage behavior over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. At lower temperatures, a significant shift of the curve relative to the results at room temperature was observed. This behavior can be explained by combining Paschen's law and the ideal gas law.

  13. The effects of spin in gases

    Laloee, F.; Freed, J.H.

    1988-01-01

    Low-density gases, in which atoms are separated by large distances, have long provided an enjoyable playground for physicists. One might suppose the pleasure of the playground would by now have been exhausted by the very simplicity of low-density gases. Recent work by a number of investigators including the author shows that this is not the case low-density gases continue to serve up a rich variety of phenomena as well as counterintuitive surprises. In particular, the macroscopic properties of a gas composed of individual hydrogen or helium atoms can under special circumstances by changed dramatically by quantum-mechanical effects. According to quantum theory, the nucleus of an atom behaves in a way similar to a rotating top, which has angular momentum about its axis of rotation; that is, the nucleus has spin, known more precisely as spin angular momentum. If the atoms of a gas are spin-polarized, so that their nuclei all have their spins pointing in the same direction, the viscosity of the gas can be changed enormously and so can its ability to conduct heat. Quantum-mechanical correlations among the nuclei called spin waves, which up to now had been observed only in certain liquids and solids such as magnets, can also arise. The changes are large enough for one to say the quantum-mechanical effects have caused the gas to take on entirely new properties. In a certain sense it is amazing to think that polarizing the nuclear spins can have any effect on the macroscopic properties of the gas, since the nuclear spins are son weakly coupled to the outside world. Yet the observations are in full agreement with with theory. Moreover, because spin-polarized gases are still fairly simple systems, they can be understood in terms fundamental principles, something that is still not possible to do in the case of liquids and solids

  14. How to wrap up radioactive gases

    Keller, C

    1982-04-01

    Operating nuclear power stations produces not only solid waste. Not so well known - but they should by no means be ignored - are the radioactive gases released during fission which somehow have to be retained and 'packaged'. Gas cylinders, such as those used for oxygen or compressed air, are unsuitable for this purpose. Ingenious chemical tricks have been thought up to press the gas - especially crypton-85 - into plastic material in which it remains captured right down to its molecular structure.

  15. Glass Membrane For Controlled Diffusion Of Gases

    Shelby, James E.; Kenyon, Brian E.

    2001-05-15

    A glass structure for controlled permeability of gases includes a glass vessel. The glass vessel has walls and a hollow center for receiving a gas. The glass vessel contains a metal oxide dopant formed with at least one metal selected from the group consisting of transition metals and rare earth metals for controlling diffusion of the gas through the walls of the glass vessel. The vessel releases the gas through its walls upon exposure to a radiation source.

  16. Agreements on emission of greenhouse gases

    Aulstad, Johan Greger

    2001-01-01

    Agreements on emission of greenhouse gases is one of the instruments used by Norwegian authorities to meet their obligations with respect to the Climate Convention and the Kyoto Protocol. This book discusses the legal issues raised by these agreements. A main topic is how the industrial emissions conform to the Pollution Act. Does the Pollution Act apply to these emissions? What is the impact of the sanction rules in this act on the emissions? The book also deals with the following general questions that arise in connection with the application of public authority: (1) Can the administration grant concessions and permits in the form of agreements? (2) What commitments can be imposed on a private party by the administration by agreement? (3) Should the procedures set down in the Pollution Act and in the Public Administration Act be followed fully when the pollution authorities make agreements? Is the opportunity of the administration to reverse more restricted when they make agreements than when they make one-sided decisions? Although this discussion primarily deals with the emission of greenhouse gases, the reasoning and conclusions are relevant in many other types of agreements in which the public administration is one of the parties. The agreement that regulates the emissions of greenhouse gases from the Norwegian aluminium industry is described in a special section. The book also gives a brief account of how agreements are used in the Danish climate policy

  17. Diffusion coefficients gases, dissolved in fluid of NPPs circulation contours

    Piontkovskij, A.I.

    2000-01-01

    In article is brought analysis of diverse gases diffusion coefficients computation methods, dissolved in liquid. On the basis of this analysis and treatment of being equalizations for concrete gases and certain parameters offers universal diffusion coefficients determination dependence for diverse gases in wide range of parameters, circulation contours typical for work NPP

  18. 30 CFR 75.322 - Harmful quantities of noxious gases.

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Harmful quantities of noxious gases. 75.322... quantities of noxious gases. Concentrations of noxious or poisonous gases, other than carbon dioxide, shall... Governmental Industrial Hygienists in “Threshold Limit Values for Substance in Workroom Air” (1972). Detectors...

  19. 76 FR 73885 - Mandatory Reporting of Greenhouse Gases

    2011-11-29

    ... Mandatory Reporting of Greenhouse Gases; Final Rule #0;#0;Federal Register / Vol. 76, No. 229 / Tuesday... 98 [EPA-HQ-OAR-2011-0147; FRL-9493-9] RIN 2060-AQ85 Mandatory Reporting of Greenhouse Gases AGENCY... the Mandatory Reporting of Greenhouse Gases Rule to correct certain technical and editorial errors...

  20. 76 FR 47391 - Mandatory Reporting of Greenhouse Gases

    2011-08-04

    ... Mandatory Reporting of Greenhouse Gases; Proposed Rule #0;#0;Federal Register / Vol. 76, No. 150 / Thursday...-HQ-OAR-2011-0147; FRL-9443-1] RIN 2060-AQ85 Mandatory Reporting of Greenhouse Gases AGENCY... provisions in the Mandatory Reporting of Greenhouse Gases Rule to correct certain technical and editorial...

  1. Thermodynamics of Quantum Gases for the Entire Range of Temperature

    Biswas, Shyamal; Jana, Debnarayan

    2012-01-01

    We have analytically explored the thermodynamics of free Bose and Fermi gases for the entire range of temperature, and have extended the same for harmonically trapped cases. We have obtained approximate chemical potentials for the quantum gases in closed forms of temperature so that the thermodynamic properties of the quantum gases become…

  2. Kinetic theory of nonideal gases and nonideal plasmas

    Klimontovich, Yu L

    2013-01-01

    Kinetic Theory of Nonideal Gases and Nonideal Plasmas presents the fundamental aspects of the kinetic theory of gases and plasmas. The book consists of three parts, which attempts to present some of the ideas, methods and applications in the study of the kinetic processes in nonideal gases and plasmas. The first part focuses on the classical kinetic theory of nonideal gases. The second part discusses the classical kinetic theory of fully ionized plasmas. The last part is devoted to the quantum kinetic theory of nonideal gases and plasmas. A concluding chapter is included, which presents a shor

  3. Irradiation technologies used for combustion gases and diluted sulfurous gases decontamination

    Villanueva Z, Loreto

    1998-01-01

    A brief description of irradiation technology used for ambient decontamination is presented here. The system is adequate fort gas and liquid effluents and solid wastes. In particular, the characteristics and applications of the irradiation done with an electron beam to gas effluent is described, mainly to clean combustion gases and other industrial gases containing sulfur and nitrogen oxides, S O x and N O x , respectively. This technology permits the remove of these contaminants and the acquisition of a solid byproduct, an ammonia sulfate-nitrate, apt for fertilizer applications. (author)

  4. Diffusive retention of atmospheric gases in chert

    Pettitt, E.; Cherniak, D. J.; Watson, E. B.; Schaller, M. F.

    2016-12-01

    Throughout Earth's history, the volatile contents (N2, CO2, Ar) of both deep and shallow terrestrial reservoirs has been dynamic. Volatiles are important chemical constituents because they play a significant role in regulating Earth's climate, mediating the evolution of complex life, and controlling the properties of minerals and rocks. Estimating levels of atmospheric volatiles in the deep geological past requires interrogation of materials that have acquired and retained a chemical memory from that time. Cherts have the potential to trap atmospheric components during formation and later release those gases for analysis in the laboratory. However, cherts have been underexploited in this regard, partly because their ability to retain a record of volatile components has not been adequately evaluated. Before cherts can be reliably used as indicators of past levels of major atmospheric gases, it is crucial that we understand the diffusive retentiveness of these cryptocrystalline silica phases. As the first step toward quantifying the diffusivity and solubility of carbon dioxide and nitrogen in chert, we have performed 1-atmosphere diffusive-uptake experiments at temperatures up to 450°C. Depth profiles of in-diffusing gases are measured by nuclear reaction analysis (NRA) to help us understand the molecular-scale transport of volatiles and thus the validity of using chert-bound volatiles to record information about Earth history. Data collected to date suggest that at least some cherts are ideal storage containers and can retain volatiles for a geologically long time. In addition to these diffusion experiments, preliminary online-crush fast-scan measurements using a quadrupole mass spectrometer indicate that atmospheric volatiles are released upon crushing various chert samples. By coupling such volatile-release measurements made by mass spectrometry with diffusion experiments, we are uniquely able to address the storage and fidelity of volatiles bound in crustal

  5. Method for detecting trace impurities in gases

    Freund, S.M.; Maier, W.B. II; Holland, R.F.; Beattie, W.H.

    A technique for considerably improving the sensitivity and specificity of infrared spectrometry as applied to quantitative determination of trace impurities in various carrier or solvent gases is presented. A gas to be examined for impurities is liquefied and infrared absorption spectra of the liquid are obtained. Spectral simplification and number densities of impurities in the optical path are substantially higher than are obtainable in similar gas-phase analyses. Carbon dioxide impurity (approx. 2 ppM) present in commercial Xe and ppM levels of Freon 12 and vinyl chloride added to liquefied air are used to illustrate the method.

  6. Positron scattering from noble gases future prospects

    Jones, A C L; Caradonna, P; Makochekanwa, C; Slaughter, D S; Sullivan, J P; Buckman, S J [Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, Australian National University, Canberra, ACT (Australia); Mitroy, J, E-mail: acj107@rsphysse.anu.edu.a [Faculty of Education Health and Science, Charles Darwin University, NT (Australia)

    2009-11-01

    Recent results for positron scattering from noble gases over an energy range from 0.5 to 60eV are presented. Measurements include the grand total ({sigma}{sub GT}), Ps formation ({sigma}{sub Ps}) and Grand total - Ps formation (({sigma}{sub GT}-P{sub s}) cross sections. Some preliminary DCS results will also be presented. Work on a formulation of modified effective range theory (MERT) is being undertaken to determine the value of the scattering length which may be useful for identifying a bound state. Plans for experiments on metal atoms will be outlined.

  7. Characteristic of combustion of Colombian gases

    Gil B, Edison; Maya, Ruben; Andres, Amel A.

    1996-01-01

    The variety of gas locations in the country, makes that the gas that will be distributed by the net of present gas pipeline a very different composition, what bears to that these they behave in a different way during its use. In this work the main characteristics of the combustion are calculated for the Colombian gases, basically the properties of the combustion and the characteristics of the smoke, as basic information for the design and operation of the gas teams and their certification. These properties were calculated with the special help software for combustion developed by the authors

  8. Effect of Greenhouse Gases Dissolved in Seawater

    Shigeki Matsunaga

    2015-12-01

    Full Text Available A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region.

  9. Gases and vacua handbook of vacuum physics

    Beck, A H

    2013-01-01

    Handbook of Vacuum Physics, Volume 1: Gases and Vacua provides information on the many aspects of vacuum technology, from material on the quantum theoretical aspects of the complex semi-conductors used for thermionic and photo-electric emission to data on the performance of commercially available pumps, gauges, and high-vacuum materials. The handbook satisfies the need of workers using vacuum apparatuses or works on the diverse applications of high-vacuum technology in research and industry. The book is a compilation of long articles prepared by experts in vacuum technology. Sufficient theoret

  10. Mean free path in soccer and gases

    Luzuriaga, J, E-mail: luzuriag@cab.cnea.gov.a [Centro Atomico Bariloche - CNEA, Instituto Balseiro UNC (8400), Bariloche (Argentina)

    2010-09-15

    The trajectories of the molecules in an ideal gas and of the ball in a soccer game are compared. The great difference between these motions and some similarities are discussed. This example could be suitable for discussing many concepts in kinetic theory in a way that can be pictured by students for getting a more intuitive understanding. It could be suitable for an introductory course in vacuum techniques or undergraduate courses in kinetic theory of gases. Without going into the slightly harder quantitative results, the analysis presented might be used for introducing some ideas of kinetic theory qualitatively to high school students.

  11. Mean free path in soccer and gases

    Luzuriaga, J

    2010-01-01

    The trajectories of the molecules in an ideal gas and of the ball in a soccer game are compared. The great difference between these motions and some similarities are discussed. This example could be suitable for discussing many concepts in kinetic theory in a way that can be pictured by students for getting a more intuitive understanding. It could be suitable for an introductory course in vacuum techniques or undergraduate courses in kinetic theory of gases. Without going into the slightly harder quantitative results, the analysis presented might be used for introducing some ideas of kinetic theory qualitatively to high school students.

  12. Surface dependency in thermodynamics of ideal gases

    Sisman, Altug

    2004-01-01

    The Casimir-like size effect rises in ideal gases confined in a finite domain due to the wave character of atoms. By considering this effect, thermodynamic properties of an ideal gas confined in spherical and cylindrical geometries are derived and compared with those in rectangular geometry. It is seen that an ideal gas exhibits an unavoidable quantum surface free energy and surface over volume ratio becomes a control variable on thermodynamic state functions in microscale. Thermodynamics turns into non-extensive thermodynamics and geometry difference becomes a driving force since the surface over volume ratio depends on the geometry

  13. Pairing fluctuations in trapped Fermi gases

    Viverit, Luciano; Bruun, Georg M.; Minguzzi, Anna; Fazio, Rosario

    2004-01-01

    We examine the contribution of pairing fluctuations to the superfluid order parameter for harmonically trapped atomic Fermi gases in the BCS regime. In the limit of small systems we consider, both analytically and numerically, their space and temperature dependence. We predict a parity effect, i.e., that pairing fluctuations show a maximum or a minimum at the center of the trap, depending on the value of the last occupied shell being even or odd. We propose to detect pairing fluctuations by measuring the density-density correlation function after a ballistic expansion of the gas

  14. Neutrino oscillations in dense neutrino gases

    Samuel, S.

    1993-01-01

    We consider oscillations of neutrinos under conditions in which the neutrino density is sufficiently large that neutrino-neutrino interactions cannot be neglected. A formalism is developed to treat this highly nonlinear system. Numerical analysis reveals a rich array of phenomena. In certain gases, a self-induced Mikheyev-Smirnov-Wolfenstein effect occurs in which electron neutrinos are resonantly converted into muon neutrinos. In another relatively low-density gas, an unexpected parametric resonant conversion takes place. Finally, neutrino-neutrino interactions maintain coherence in one system for which a priori one expected decoherence

  15. On the velocity distributions of granular gases

    Polito, A.M.M.; Rocha Filho, T.M.; Figueiredo, A.

    2009-01-01

    We present a new approach to determine velocity distributions in granular gases to improve the Sonine polynomial expansion of the velocity distribution function, at higher inelasticities, for the homogeneous cooling regime of inelastic hard spheres. The perturbative consistency is recovered using a new set of dynamical variables based on the characteristic function and we illustrate our approach by computing the first four Sonine coefficients for moderate and high inelasticities. The analytical coefficients are compared with molecular dynamics simulations results and with a previous approach by Huthmann et al.

  16. Method for monitoring stack gases for uranium activity

    Beverly, C.R.; Ernstberger, H.G.

    1988-01-01

    A method for sampling stack gases emanating from the purge cascade of a gaseous diffusion cascade system utilized to enrich uranium for determining the presence and extent of uranium in the stack gases in the form of gaseous uranium hexafluoride, is described comprising the steps of removing a side stream of gases from the stack gases, contacting the side stream of the stack gases with a stream of air sufficiently saturated with moisture for reacting with and converting any gaseous uranium hexafluroide contracted thereby in the side stream of stack gases to particulate uranyl fluoride. Thereafter contacting the side stream of stack gases containing the particulate uranyl fluoride with moving filter means for continuously intercepting and conveying the intercepted particulate uranyl fluoride away from the side stream of stack gases, and continually scanning the moving filter means with radiation monitoring means for sensing the presence and extent of particulate uranyl fluoride on the moving filter means which is indicative of the extent of particulate uranyl fluoride in the side stream of stack gases which in turn is indicative of the presence and extent of uranium hexafluoride in the stack gases

  17. Spectral Line Shapes in Plasmas and Gases

    Oks, E.; Dalimier, D.; Stamm, R.; Stehle, CH.; Gonzalez, M.A.

    2011-01-01

    The subject of spectral line shapes (SLS), a.k.a. spectral line broadening, which embraces both shapes and shifts of spectral lines, is of both fundamental and practical importance. On the fundamental side, the study of the spectral line profiles reveals the underlying atomic and molecular interactions. On the practical side, the spectral line profiles are employed as powerful diagnostic tools for various media, such as neutral gases, technological gas discharges, magnetically confined plasmas for fusion, laser- and Z-pinch-produced plasmas (for fusion and other purposes), astrophysical plasmas (most importantly, solar plasmas), and planetary atmospheres. The research area covered by this special issue includes both the SLS dominated by various electric fields (including electron and ion micro fields in strongly ionized plasmas) and the SLS controlled by neutral particles. In the physical slang, the former is called plasma broadening while the latter is called neutral broadening (of course, the results of neutral broadening apply also to the spectral line broadening in neutral gases)

  18. Corrosion by cooling gases in nuclear reactors

    Darras, R.

    1960-01-01

    This article begins with a review of the various materials which can be used and the cooling gases in which they may be heated, emphasis being placed on the importance of reaching temperatures as high as possible. This is followed by a few general remarks on the dry oxidation of metals and alloys, particularly with regard to diffusion phenomena and their various possible mechanisms, and also the methods of investigation employed. Finally, the behaviour of the chief nuclear materials heated in the various gases is studied successively. Materials used for fuel (metallic uranium, uranium oxide, carbides and silicides), canning materials (magnesium, aluminium, zirconium, beryllium, stainless and refractory steels), structural materials (ordinary or slightly alloyed steels), and finally moderators (graphite, beryllium oxide) are deal with in this way. This account is backed up both by the results obtained at the CEA and by work published outside or abroad up to the present day. In conclusion, every effort has been made to direct future research on the basis of the foregoing. Reprint of a paper published in Industries Atomiques - no. 9/10, 1959, p. 3-23 [fr

  19. Subcooled boiling effect on dissolved gases behaviour

    Zmitko, M.; Sinkule, J.; Linek, V.

    1999-01-01

    A model describing dissolved gasses (hydrogen, nitrogen) and ammonia behaviour in subcooled boiling conditions of WWERs was developed. Main objective of the study was to analyse conditions and mechanisms leading to formation of a zone with different concentration of dissolved gases, eg. a zone depleted in dissolved hydrogen in relation to the bulk of coolant. Both, an equilibrium and dynamic approaches were used to describe a depletion of the liquid surrounding a steam bubble in the gas components. The obtained results show that locally different water chemistry conditions can be met in the subcooled boiling conditions, especially, in the developed subcooled boiling regime. For example, a 70% hydrogen depletion in relation to the bulk of coolant takes about 1 ms and concerns a liquid layer of 1 μn surrounding the steam bubble. The locally different concentration of dissolved gases can influence physic-chemical and radiolytic processes in the reactor system, eg. Zr cladding corrosion, radioactivity transport and determination of the critical hydrogen concentration. (author)

  20. Reducing the Livestock related green house gases emission

    D Indira

    2012-08-01

    Full Text Available Cattle rearing generate more global warming green house gases than driving cars. These green house gases leads to changes in the climate. This climate change affects the livestock, man and natural environment continuously. For this reason it is important for livestock farmers to find the ways which minimize these gases emission. In this article the causes of climate change and effects, measures to be taken by farmers and their efficiency in reducing green house gases emission were reviewed briefly to make the farmers and students aware of the reduction of global warming green house gases and measures to be taken for reducing these gases. [Vet. World 2012; 5(4.000: 244-247

  1. Veracruz State Preliminary Greenhouse Gases Emissions Inventory

    Welsh Rodriguez, C.; Rodriquez Viqueira, L.; Guzman Rojas, S.

    2007-05-01

    At recent years, the international organisms such as United Nations, has discussed that the temperature has increased slightly and the pattern of precipitations has changed in different parts of the world, which cause either extreme droughts or floods and that the extreme events have increased. These are some of the risks of global climate change because of the increase of gas concentration in the atmosphere such as carbon dioxides, nitrogen oxides and methane - which increase the greenhouse effect. Facing the consequences that could emerge because of the global temperature grown, there is a genuine necessity in different sectors of reduction the greenhouse gases and reduced the adverse impacts of climate change. To solve that, many worldwide conventions have been realized (Rio de Janeiro, Kyoto, Montreal) where different countries have established political compromises to stabilize their emissions of greenhouse gases. The mitigation and adaptation policies merge as a response to the effects that the global climate change could have, on the humans as well as the environment. That is the reason to provide the analysis of the areas and geographic zones of the country that present major vulnerability to the climate change. The development of an inventory of emissions that identifies and quantifies the principal sources of greenhouse gases of a country, and also of a region is basic to any study about climate change, also to develop specific political programs that allow to preserve and even improve a quality of the atmospheric environment, and maybe to incorporate to international mechanisms such as the emissions market. To estimate emissions in a systematic and consistent way on a regional, national and international level is a requirement to evaluate the feasibility and the cost-benefit of instrumented possible mitigation strategies and to adopt politics and technologies to reduce emissions. Mexico has two national inventories of emissions, 1990 and 1995, now it is

  2. Relativistic quantum thermodynamics of ideal gases in two dimensions.

    Blas, H; Pimentel, B M; Tomazelli, J L

    1999-11-01

    In this work we study the behavior of relativistic ideal Bose and Fermi gases in two space dimensions. Making use of polylogarithm functions we derive a closed and unified expression for their densities. It is shown that both type of gases are essentially inequivalent, and only in the non-relativistic limit the spinless and equal mass Bose and Fermi gases are equivalent as known in the literature.

  3. Relativistic Quantum Thermodynamics of Ideal Gases in 2 Dimensions

    Blas, H.; Pimentel, B. M.; Tomazelli, J. L.

    1999-01-01

    In this work we study the behavior of relativistic ideal Bose and Fermi gases in two space dimensions. Making use of polylogarithm functions we derive a closed and unified expression for their densities. It is shown that both type of gases are essentially inequivalent, and only in the non-relativistic limit the spinless and equal mass Bose and Fermi gases are equivalent as known in the literature.

  4. Experimental study of energy exchanges between two coupled granular gases

    Chastaing , J.-Y; Géminard , J.-C; Naert , A

    2016-01-01

    International audience; We report on the energy exchanges between two granular gases of different densities coupled electrome-chanically by immersed blades attached to dc motors. Zeroing the energy flux between the two subsystems, we demonstrate that an immersed blade is a convenient way to assess the properties of the granular gases, provided that the dissipation in the motor is properly taken into account. In addition, when the two gases have different densities, the fluctuations of the ene...

  5. Properties of gases, liquids, and solutions principles and methods

    Mason, Warren P

    2013-01-01

    Physical Acoustics: Principles and Methods, Volume ll-Part A: Properties of Gases, Liquids, and Solutions ponders on high frequency sound waves in gases, liquids, and solids that have been proven as effective tools in examining the molecular, domain wall, and other types of motions. The selection first offers information on the transmission of sound waves in gases at very low pressures and the phenomenological theory of the relaxation phenomena in gases. Topics include free molecule propagation, phenomenological thermodynamics of irreversible processes, and simultaneous multiple relaxation pro

  6. Deviation from the Knudsen law on quantum gases

    Babac, Gulru

    2014-01-01

    Gas flow in micro/nano scale systems has been generally studied for the Maxwell gases. In the limits of very low temperature and very confined domains, the Maxwellian approximation can break down and the quantum character of the gases becomes important. In these cases, Knudsen law, which is one of the important equations to analyze rarefied gas flows is invalid and should be reanalyzed for quantum gases. In this work, the availability of quantum gas conditions in the high Knudsen number cases is discussed and Knudsen law is analyzed for quantum gases

  7. Generation and release of radioactive gases in LLW disposal facilities

    Yim, M.S. [Harvard School Public Health, Boston, MA (United States); Simonson, S.A. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    1995-02-01

    The atmospheric release of radioactive gases from a generic engineered LLW disposal facility and its radiological impacts were examined. To quantify the generation of radioactive gases, detailed characterization of source inventory for carbon-14, tritium, iodine-129, krypton-85, and radon-222, was performed in terms of their activity concentrations; their distribution within different waste classes, waste forms and containers; and their subsequent availability for release in volatile or gaseous form. The generation of gases was investigated for the processes of microbial activity, radiolysis, and corrosion of waste containers and metallic components in wastes. The release of radionuclides within these gases to the atmosphere was analyzed under the influence of atmospheric pressure changes.

  8. Hydrogen Peroxide Enhances Removal of NOx from Flue Gases

    Collins, Michelle M.

    2005-01-01

    Pilot scale experiments have demonstrated a method of reducing the amounts of oxides of nitrogen (NOx) emitted by industrial boilers and powerplant combustors that involves (1) injection of H2O2 into flue gases and (2) treatment of the flue gases by caustic wet scrubbing like that commonly used to remove SO2 from combustion flue gases. Heretofore, the method most commonly used for removing NOx from flue gases has been selective catalytic reduction (SCR), in which the costs of both installation and operation are very high. After further development, the present method may prove to be an economically attractive alternative to SCR.

  9. Reactions on carbonaceous materials with hydrogenating gases

    Pier, M; Simon, W; Kronig, W

    1933-02-08

    A process is given for the production of valuable hydrocarbons by treatment of distillable carbonaceous materials with added hydrogenating gases under pressure in contact with catalysts. The process comprises adding to the initial materials before or during the said treatment organic sulphonic acids together with metals of groups 4 to 8 of the periodic system or compounds thereof, or free organic carboxylic acids which when inorganic salts are simultaneously present do not combine therewith to form complex ansolvo acids, or acid salts of strong acids or acid salts of heavy metals, lithium, magnesium, and aluminum, with the exception of aluminum hydrosilicates, or inorganic oxygen containing acids of sulfur or nitrogen or the anhydrides of said inorganic oxygen-containing acids.

  10. Voluntary reporting of greenhouse gases 1997

    NONE

    1999-05-01

    The Voluntary Reporting of Greenhouse Gases Program, required by Section 1605(b) of the Energy Policy Act of 1992, records the results of voluntary measures to reduce, avoid, or sequester greenhouse gas emissions. In 1998, 156 US companies and other organizations reported to the Energy information Administration that, during 1997, they had achieved greenhouse gas emission reductions and carbon sequestration equivalent to 166 million tons of carbon dioxide, or about 2.5% of total US emissions for the year. For the 1,229 emission reduction projects reported, reductions usually were measured by comparing an estimate of actual emissions with an estimate of what emissions would have been had the project not been implemented.

  11. Gender and Boyle's law of gases

    Potter, Elizabeth

    2001-01-01

    Gender and Boyle''s Law of GasesElizabeth PotterRe-examines the assumptions and experimental evidence behind Boyle''s Law.Boyle''s Law, which describes the relation between the pressure and volume of a gas, was worked out by Robert Boyle in the mid-1600s. His experiments are still considered examples of good scientific work and continue to be studied along with their historical and intellectual contexts by philosophers, historians, and sociologists. Now there is controversy over whether Boyle''s work was based only on experimental evidence or whether it was influenced by the politics and religious controversies of the time, including especially class and gender politics.Elizabeth Potter argues that even good science is sometimes influenced by such issues, and she shows that the work leading to the Gas Law, while certainly based on physical evidenc...

  12. Explorative analysis of microbes, colloids and gases

    Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB, Goeteborg (Sweden))

    2008-08-15

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. In this report, part of the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and Univ. researchers with expertise in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. This report focuses on microbiology, colloids and gases: - Microbes (Chapter 1): Several methods must be used to characterize active microbial communities in groundwater. Microbial parameters of interest are the total number of cells (TNC) and the presence of various metabolic groups of microorganisms. Different microbial groups influence the environment in different ways, depending on what metabolic group is dominant. Typically, the following redox couples are utilized by bacteria in granitic groundwater: H{sub 2}O/O{sub 2}, NO{sub 3}-/N{sub 2}, Mn2+/Mn(IV), Fe2+/Fe(III), S2-/SO{sub 4}2-, CH{sub 4}/CO{sub 2}, CH{sub 3}COOH/CO{sub 2}, and H{sub 2}/H+. The data will indicate the activity of specific microbial populations at particular sites and how they may affect the geochemistry. - Colloids (Chapter 2): Particles in the size range from 1 to 1x10-3 mum are regarded as colloids. Their small size prohibits them from settling, which gives them the

  13. Retention of nitrous gases in scrubber columns

    Nakazone, A.K.; Costa, R.C.; Lobao, A.S.T.; Matsuda, H.T.; Araujo, B.F. de

    1988-01-01

    During the UO 2 dissolution in nitric acid, some different species of NO (sub)x are released. The off gas can either be refluxed to the dissolver or be released and retained on special colums. The final composition of the solution is the main parameter to take in account. A process for nitrous gases retention using scrubber colums containing H 2 O or diluted HNO 3 is presented. Chemiluminescence measurement was employed to NO x evaluation before and after scrubing. Gas flow, temperature, residence time are the main parameters considered in this paper. For the dissolution of 100g UO 2 in 8M nitric acid, a 6NL/h O 2 flow was the best condition for the NO/NO 2 oxidation with maximum absorption in the scrubber columns. (author) [pt

  14. Critical discharge of fluids and gases

    Seewald, Michael

    2012-01-01

    The thermal hydraulic relations during discharge of fluids and gases are complex and a closed solution does not seem to be available. For the modeling of leakage accidents in nuclear power plants basic considerations are suitable for statements on the maximum mass flow, and thus the leak rate. The maximum mass flow is reached when the critical velocity is reached in the smallest cross section. This allows the appropriate design of safety systems for one-phase and two-phase flows. For German NPP simulators the hydrodynamics simulation program RELAP5-3D is used. The simulator center operates a 1:10 scale gas model of a two-loop PWR type reactor. The observable phenomena have occurred in nuclear power plants. The characteristics for a visualization of two-phase flows are not available in the simulation software and have to be added by correlations with experimental results. The realization of expectations on digital visualization techniques is discussed.

  15. Electron beam processing of combustion flue gases

    1987-07-01

    This report contains the papers presented at the consultants' meeting on electron beam processing of combustion flue gases. The meeting provided an excellent opportunity for exchanging information and reviewing the current status of technology development. Characteristics of the electron beam processing recognized by the meeting are: capability of simultaneous removals of SO 2 and NO x , safe technology and simplicity of control, dry process without waste water to be treated, cost benefit of electron beam processing compared with conventional technology and the conversion of SO 2 and NO x to a by-product that can be used as agricultural fertilizer. A separate abstract was prepared for each of the 22 papers in this technical report

  16. Thermal Plasma decomposition of fluoriated greenhouse gases

    Choi, Soo Seok; Watanabe, Takayuki [Tokyo Institute of Technology, Yokohama (Japan); Park, Dong Wha [Inha University, Incheon (Korea, Republic of)

    2012-02-15

    Fluorinated compounds mainly used in the semiconductor industry are potent greenhouse gases. Recently, thermal plasma gas scrubbers have been gradually replacing conventional burn-wet type gas scrubbers which are based on the combustion of fossil fuels because high conversion efficiency and control of byproduct generation are achievable in chemically reactive high temperature thermal plasma. Chemical equilibrium composition at high temperature and numerical analysis on a complex thermal flow in the thermal plasma decomposition system are used to predict the process of thermal decomposition of fluorinated gas. In order to increase economic feasibility of the thermal plasma decomposition process, increase of thermal efficiency of the plasma torch and enhancement of gas mixing between the thermal plasma jet and waste gas are discussed. In addition, noble thermal plasma systems to be applied in the thermal plasma gas treatment are introduced in the present paper.

  17. Aerodynamic features of flames in premixed gases

    Oppenheim, A. K.

    1984-01-01

    A variety of experimentally established flame phenomena in premixed gases are interpreted by relating them to basic aerodynamic properties of the flow field. On this basis the essential mechanism of some well known characteristic features of flames stabilized in the wake of a bluff-body or propagating in ducts are revealed. Elementary components of the flame propagation process are shown to be: rotary motion, self-advancement, and expansion. Their consequences are analyzed under a most strict set of idealizations that permit the flow field to be treated as potential in character, while the flame is modelled as a Stefan-like interface capable of exerting a feed-back effect upon the flow field. The results provide an insight into the fundamental fluid-mechanical reasons for the experimentally observed distortions of the flame front, rationalizing in particular its ability to sustain relatively high flow velocities at amazingly low normal burning speeds.

  18. Inerting Aircraft Fuel Systems Using Exhaust Gases

    Hehemann, David G.

    2002-01-01

    Our purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A aircraft fuel. In particular, we looked at the solubility of CO2 in Jet-A fuel, the pumpability of CO2-saturated Jet-A fuel, the flashpoint of Jet-A fuel under various mixtures of air and CO2, the static outgassing of CO2-Saturated Jet-A fuel and the dynamic outgassing of Jet-A fuel during pumping of Jet-A fuel.

  19. Report of Committee H. Liquefied gases

    Miyata, Yoshiaki

    1997-01-01

    Committee H covers liquefied gases, both liquefied natural gas (LNG) and liquefied petroleum gas (LPG). In this triennium (1994-1997), Subcommittee H-1 and H-2 carried out a general survey of LNG and LPG respectively including supply and demand, world LNG trade, LPG production facilities, LNG liquefaction plants, LNG schemes existing or under construction and future projects. Additionally five working groups were set up to cover the following work items selected from among major topics that the liquefied gas industries are facing or concerned with. The topics for LNG are ''Operational aspects of liquefaction plants'', ''Cost reduction of LNG chains'', ''Evolution of major cryogenic equipment'' and those for LPG are ''New developments in future LPG utilization'' and ''LPG: An optimal fuel for developing countries''. It should be noted that, in addition to traditional surveys, Committee H also tried making a cost analysis of LNG chains for the first time, in ''Cost reduction of LNG chains''. (au)

  20. Method of extracting shale with hot gases

    Hervier, M

    1874-12-05

    The raw rock is treated in a furnace composed of a series of compartments arranged in a circle around a hearth and communicating with one another by means of a chimney. The chargers receiving the rock communicate at the top directly with little cells in which terminate the chimneys for the circulation. These chambers are accessible to the combustion gases from the central hearth by means of flues. A damper, operated from outside, closes the chimney or flue at will. A grill is installed at the lower part of each chamber and supports the bituminous rocks to be treated, the rock being charged in at the top of the chamber. Each chamber is set on a reservoir of cast iron, the reservoir being slightly inclined toward the outside and receiving the liquid products separated from the rock.

  1. A New Perspective on Classical Ideal Gases

    Fabrice Philippe

    2013-08-01

    Full Text Available The ideal-gas barometric and pressure laws are derived from the Democritian concept of independent corpuscles moving in vacuum, plus a principle of simplicity, namely that these laws are independent of the kinetic part of the Hamiltonian. A single corpuscle in contact with a heat bath in a cylinder and submitted to a constant force (weight is considered. The paper importantly supplements a previously published paper: First, the stability of ideal gases is established. Second, we show that when walls separate the cylinder into parts and are later removed, the entropy is unaffected. We obtain full agreement with Landsberg’s and others’ (1994 classical thermodynamic result for the entropy of a column of gas submitted to gravity.

  2. Human activities affecting trace gases and climate

    Braatz, B.; Ebert, C.

    1990-01-01

    The Earth's climate has been in a constant state of change throughout geologic time due to natural perturbations in the global geobiosphere. However, various human activities have the potential to cause future global warming over a relatively short amount of time. These activities, which affect the Earth's climate by altering the concentrations of trace gases in the atmosphere, include energy consumption, particularly fossil-fuel consumption; industrial processes (production and use of chlorofluorocarbons, halons, and chlorocarbons, landfilling of wastes, and cement manufacture); changes in land use patterns, particularly deforestation and biomass burning; and agricultural practices (waste burning, fertilizer usage, rice production, and animal husbandry). Population growth is an important underlying factor affecting the level of growth in each activity. This paper describes how the human activities listed above contribute to atmospheric change, the current pattern of each activity, and how levels of each activity have changed since the early part of this century

  3. Explorative analysis of microbes, colloids and gases

    Hallbeck, Lotta; Pedersen, Karsten

    2008-08-01

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. In this report, part of the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and Univ. researchers with expertise in geochemistry, hydrochemistry, hydrogeochemistry, microbiology, geomicrobiology, analytical chemistry etc. The resulting site descriptive model version, mainly based on 2.2 data and complementary 2.3 data, was carried out during September 2006 to December 2007. This report focuses on microbiology, colloids and gases: - Microbes (Chapter 1): Several methods must be used to characterize active microbial communities in groundwater. Microbial parameters of interest are the total number of cells (TNC) and the presence of various metabolic groups of microorganisms. Different microbial groups influence the environment in different ways, depending on what metabolic group is dominant. Typically, the following redox couples are utilized by bacteria in granitic groundwater: H 2 O/O 2 , NO 3 - /N 2 , Mn 2+ /Mn(IV), Fe 2+ /Fe(III), S 2- /SO 4 2- , CH 4 /CO 2 , CH 3 COOH/CO 2 , and H 2 /H + . The data will indicate the activity of specific microbial populations at particular sites and how they may affect the geochemistry. - Colloids (Chapter 2): Particles in the size range from 1 to 1x10 -3 μm are regarded as colloids. Their small size prohibits them from settling, which gives them the potential to transport

  4. Dosimetry of the radioactive noble gases

    Soldat, J.K.; Bramson, P.E.; Parker, H.M.

    1973-01-01

    Methods are described that were used for estimations of the radiation dose rate to various human tissues from the radioactive gases of Ar, Kr, and Xe following inhalation or immersion in a semi-infinite cloud. Dose rates to the whole-body, lungs, adipose tissues, and testes were calculated following inhalation; and dose rates to the skin, whole-body, lungs, and testes from a semi-infinite cloud were calculated for 39 Ar, 41 Ar, 83 Kr, 85 Kr, 87 Kr, 88 Kr, 131 Xe, 133 Xe, 135 Xe, 137 Xe, 138 Xe, and also 88 Rb found in equilibrium with its parent 88 Kr and 138 Cs found in equilibrium with its parent 138 Xe. (U.S.)

  5. Lessons from geothermal gases at Yellowstone

    Lowenstern, J. B.; Bergfeld, D.; Evans, W.; Hurwitz, S.

    2015-12-01

    The magma-hydrothermal system of the Yellowstone Plateau Volcanic Field encompasses over ten thousand individual springs, seeps, and fumaroles spread out over >9000 square kilometers, and produces a range of acid, neutral and alkaline waters. A prominent model (Fournier, 1989 and related papers) concludes that many neutral and alkaline fluids found in hot springs and geysers are derived from a uniform, high-enthalpy parent fluid through processes such as deep boiling and mixing with dilute meteoric groundwater. Acid waters are generally condensates of gas-bearing steam that boils off of subsurface geothermal waters. Our recent studies of gases at Yellowstone (Lowenstern et al., 2015 and references therein) are compatible with such a model, but also reveal that gases are largely decoupled from thermal waters due to open-system addition of abundant deep gas to (comparatively) shallow circulating thermal waters. Fumarole emissions at Yellowstone range from gas-rich (up to 15 mol%) composed of deeply derived CO2, He and CH4, to steam-rich emissions (16 RA) and low CH4 and He concentrations and 2) mantle-derived CO2 with much higher CH4 and/or He concentrations and abundant radiogenic He picked up from crustal degassing. Individual thermal areas have distinct CH4/He. It remains unclear whether some gas ratios mainly reflect subsurface geothermal temperatures. Instead, they may simply reflect signatures imparted by local rock types and mixing on timescales too fast for reequilibration. Overall, the gas chemistry reflects a broader view of mantle-crust dynamics than can be appreciated by studies of only dissolved solutes in the neutral and alkaline waters from Yellowstone geysers. Fournier (1989) Ann. Rev. Earth Planet. Sci. v. 17, p. 13-53. Lowenstern et al. (2015) JVGR, v. 302, 87-101.

  6. Phase structure of strongly correlated Fermi gases

    Roscher, Dietrich

    2015-01-01

    Strongly correlated fermionic many-body systems are ubiquitous in nature. Their theoretical description poses challenging problems which are further complicated when imbalances in, e.g., the particle numbers of the involved species or their masses are introduced. In this thesis, a number of different approaches is developed and applied in order to obtain predictions for physical observables of such systems that mutually support and confirm each other. In a first step, analytically well-founded mean-field analyses are carried through. One- and three-dimensional ultracold Fermi gases with spin and mass imbalance as well as Gross-Neveu and NJL-type relativistic models at finite baryon chemical potential are investigated with respect to their analytic properties in general and the occurrence of spontaneous breaking of translational invariance in particular. Based on these studies, further methods are devised or adapted allowing for investigations also beyond the mean-field approximation. Lattice Monte Carlo simulations with imaginary imbalance parameters are employed to surmount the infamous sign problem and compute the equation of state of the respective unitary Fermi gases. Moreover, in-medium two-body analyses are used to confirm and explain the characteristics of inhomogeneously ordered phases. Finally, functional RG methods are applied to the unitary Fermi gas with spin and mass imbalance. Besides quantitatively competitive predictions for critical temperatures for the superfluid state, strong hints on the stability of inhomogeneous phases with respect to order parameter fluctuations in the regime of large mass imbalance are obtained. Combining the findings from these different theoretical studies suggests the possibility to find such phases in experiments presently in preparation.

  7. From ultracold Fermi Gases to Neutron Stars

    Salomon, Christophe

    2012-02-01

    Ultracold dilute atomic gases can be considered as model systems to address some pending problem in Many-Body physics that occur in condensed matter systems, nuclear physics, and astrophysics. We have developed a general method to probe with high precision the thermodynamics of locally homogeneous ultracold Bose and Fermi gases [1,2,3]. This method allows stringent tests of recent many-body theories. For attractive spin 1/2 fermions with tunable interaction (^6Li), we will show that the gas thermodynamic properties can continuously change from those of weakly interacting Cooper pairs described by Bardeen-Cooper-Schrieffer theory to those of strongly bound molecules undergoing Bose-Einstein condensation. First, we focus on the finite-temperature Equation of State (EoS) of the unpolarized unitary gas. Surprisingly, the low-temperature properties of the strongly interacting normal phase are well described by Fermi liquid theory [3] and we localize the superfluid phase transition. A detailed comparison with theories including recent Monte-Carlo calculations will be presented. Moving away from the unitary gas, the Lee-Huang-Yang and Lee-Yang beyond-mean-field corrections for low density bosonic and fermionic superfluids are quantitatively measured for the first time. Despite orders of magnitude difference in density and temperature, our equation of state can be used to describe low density neutron matter such as the outer shell of neutron stars. [4pt] [1] S. Nascimbène, N. Navon, K. Jiang, F. Chevy, and C. Salomon, Nature 463, 1057 (2010) [0pt] [2] N. Navon, S. Nascimbène, F. Chevy, and C. Salomon, Science 328, 729 (2010) [0pt] [3] S. Nascimbène, N. Navon, S. Pilati, F. Chevy, S. Giorgini, A. Georges, and C. Salomon, Phys. Rev. Lett. 106, 215303 (2011)

  8. Oral contraceptives induced hepatotoxicity

    B. Akshaya Srikanth; V. Manisree

    2013-01-01

    Oral Contraceptives are the pharmacological agents used to prevent pregnancy. These are divided as the combined and progestogen methods and are administered orally, transdermally, systemically and via vaginal route. All these methods contain both oestrogen and progestogen. Vigorous usage of oral contraceptives and anabolic steroids as associated with cholestasis, vascular lesions and hepatic neoplasm. Benign hepatic neoplasms are clearly associated with oral contraceptives. In this article we...

  9. Oral vaccination of fish

    Embregts, Carmen W.E.; Forlenza, Maria

    2016-01-01

    The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen breakdown in the harsh gastric environment, but also to the high tolerogenic gut environment and to inadequate vaccine design. In this review we discuss current approaches used to develop oral vaccines fo...

  10. History of chemically and radiatively important atmospheric gases from the Advanced Global Atmospheric Gases Experiment (AGAGE

    R. G. Prinn

    2018-06-01

    Full Text Available We present the organization, instrumentation, datasets, data interpretation, modeling, and accomplishments of the multinational global atmospheric measurement program AGAGE (Advanced Global Atmospheric Gases Experiment. AGAGE is distinguished by its capability to measure globally, at high frequency, and at multiple sites all the important species in the Montreal Protocol and all the important non-carbon-dioxide (non-CO2 gases assessed by the Intergovernmental Panel on Climate Change (CO2 is also measured at several sites. The scientific objectives of AGAGE are important in furthering our understanding of global chemical and climatic phenomena. They are the following: (1 to accurately measure the temporal and spatial distributions of anthropogenic gases that contribute the majority of reactive halogen to the stratosphere and/or are strong infrared absorbers (chlorocarbons, chlorofluorocarbons – CFCs, bromocarbons, hydrochlorofluorocarbons – HCFCs, hydrofluorocarbons – HFCs and polyfluorinated compounds (perfluorocarbons – PFCs, nitrogen trifluoride – NF3, sulfuryl fluoride – SO2F2, and sulfur hexafluoride – SF6 and use these measurements to determine the global rates of their emission and/or destruction (i.e., lifetimes; (2 to accurately measure the global distributions and temporal behaviors and determine the sources and sinks of non-CO2 biogenic–anthropogenic gases important to climate change and/or ozone depletion (methane – CH4, nitrous oxide – N2O, carbon monoxide – CO, molecular hydrogen – H2, methyl chloride – CH3Cl, and methyl bromide – CH3Br; (3 to identify new long-lived greenhouse and ozone-depleting gases (e.g., SO2F2, NF3, heavy PFCs (C4F10, C5F12, C6F14, C7F16, and C8F18 and hydrofluoroolefins (HFOs; e.g., CH2  =  CFCF3 have been identified in AGAGE, initiate the real-time monitoring of these new gases, and reconstruct their past histories from AGAGE, air archive, and firn air measurements; (4

  11. Oral vaccination of fish

    Embregts, Carmen W.E.; Forlenza, Maria

    2016-01-01

    The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen

  12. Head, Neck, and Oral Cancer

    Full Text Available ... to detect oral cancer during your routine dental examinations. Don't risk it. Perform an oral cancer ... oral cancer self-exam each month. An oral examination is performed using a bright light and a ...

  13. Absorption of Greenhouse Gases in Liquids : A Molecular Approach

    Balaji, S.P.

    2015-01-01

    The increase in concentrations of greenhouse gases is responsible for global warming over the past few years. A major portion of the emitted greenhouse gases contains carbon dioxide (CO2). The capture of carbon dioxide from the effluent sources, its transport, and storage has been identified as the

  14. 49 CFR 229.43 - Exhaust and battery gases.

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Exhaust and battery gases. 229.43 Section 229.43... § 229.43 Exhaust and battery gases. (a) Products of combustion shall be released entirely outside the... conditions. (b) Battery containers shall be vented and batteries kept from gassing excessively. ...

  15. A Simple Experiment to Demonstrate the Effects of Greenhouse Gases

    Keating, C. F.

    2007-01-01

    The role of greenhouse gases in our atmosphere is the subject of considerable discussion and debate. Global warming is well-documented, as is the continually increasing amount of greenhouse gases that human activity puts in the air. Is there a relationship between the two? The simple experiment described in this paper provides a good demonstration…

  16. The challenges of the greenhouse gases emissions reduction in buildings

    Arnaud, E.

    2005-09-01

    The building sector is responsible of 18% of the greenhouse gases emissions in France. This document aims to evaluate the greenhouse gases emissions of the sector and then defines technical and financial avenues worth exploring to reduce them. (A.L.B.)

  17. Assessing the impact on global climate from general anesthetic gases

    Andersen, Mads P. Sulbæk; Nielsen, Ole John; Wallington, Timothy J.

    2012-01-01

    anthropogenic radiative forcing of climate, as measured relative to the start of the industrial era (approximately 1750). The family of anesthetic gases includes several halogenated organic compounds that are strong greenhouse gases. In this short report, we provide an overview of the state of knowledge...

  18. 75 FR 48743 - Mandatory Reporting of Greenhouse Gases

    2010-08-11

    ... Part II Environmental Protection Agency 40 CFR Part 98 Mandatory Reporting of Greenhouse Gases...-AQ33 Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION... Greenhouse Gas Reporting Rule Hotline at telephone number: (877) 444-1188; or e-mail: [email protected] . To...

  19. Remote control flare stack igniter for combustible gases

    Ray, W. L.

    1972-01-01

    Device has been designed and developed for igniting nonrecoverable combustible gases and sustaining combustion of gases evolving from various gas vent stacks. Igniter is superior to existing systems because of simplicity of operation, low cost fabrication, installation, operational and maintainability features, and excellent reliability in all phases of required operations.

  20. Purification technology for flue/off gases using electron beams

    Kojima, Takuji

    2004-01-01

    The present paper describes research and development on purification technology using electron beams for flue/off gases containing pollutants: removal of sulfate oxide and nitrogen oxide from flue gases of coal/oil combustion power plants, decomposition of dioxins in waste incineration flue gas, and decomposition/removal of toxic volatile organic compounds from off gas. (author)

  1. Essentials of oral cancer.

    Rivera, César

    2015-01-01

    Oral cancer is one of the 10 most common cancers in the world, with a delayed clinical detection, poor prognosis, without specific biomarkers for the disease and expensive therapeutic alternatives. This review aims to present the fundamental aspects of this cancer, focused on squamous cell carcinoma of the oral cavity (OSCC), moving from its definition and epidemiological aspects, addressing the oral carcinogenesis, oral potentially malignant disorders, epithelial precursor lesions and experimental methods for its study, therapies and future challenges. Oral cancer is a preventable disease, risk factors and natural history is already being known, where biomedical sciences and dentistry in particular are likely to improve their poor clinical indicators.

  2. Analytical methods for toxic gases from thermal degradation of polymers

    Hsu, M.-T. S.

    1977-01-01

    Toxic gases evolved from the thermal oxidative degradation of synthetic or natural polymers in small laboratory chambers or in large scale fire tests are measured by several different analytical methods. Gas detector tubes are used for fast on-site detection of suspect toxic gases. The infrared spectroscopic method is an excellent qualitative and quantitative analysis for some toxic gases. Permanent gases such as carbon monoxide, carbon dioxide, methane and ethylene, can be quantitatively determined by gas chromatography. Highly toxic and corrosive gases such as nitrogen oxides, hydrogen cyanide, hydrogen fluoride, hydrogen chloride and sulfur dioxide should be passed into a scrubbing solution for subsequent analysis by either specific ion electrodes or spectrophotometric methods. Low-concentration toxic organic vapors can be concentrated in a cold trap and then analyzed by gas chromatography and mass spectrometry. The limitations of different methods are discussed.

  3. Solubility of gases in water at high temperature

    Crovetto, Rosa; Fernandez Prini, R.J.; Japas, M.L.

    1981-01-01

    In the primary circuits of the PWR, it is usual to find apolar gases such as the noble gases like, nitrogen, hydrogen (deuterium) and oxygen. These gases enter into the circuit partly due to failures in the fuel elements, accidental entries of air into the system and corrosion processes and radiolisis in the coolant media. For the operation of several auxiliary systems in the primary circuit, it is important to know the solubility of these gases in the flux of the circuit and the evaluation of physicochemical processes that take place. A cell has been built that allows to carry out determinations of solubility in the range of 350 deg C and 100 Mega Pascal. Three alternative experimental techniques have been developed to determine the solubility of the gases which are compared to each other. Measures of solubility of argon in H2O and D2O have been made in a wide range of temperatures. (V.B.) [es

  4. Reduction of Climate Gases by Energy Efficiency

    Moe, N.

    1998-01-01

    Carbon dioxide cannot be depolluted in practice. However, there are two areas where measures can be taken to avoid CO 2 emissions: 1. Energy-efficiency. 2. Use of sustainable energy sources in energy production. It is characteristic that many measures which are good for the environment are also good from the point of view of cost efficiency, preparedness and employment. This is tru, for instance, of the greater use of biofuels instead of fossil fuels, collective heating systems as opposed to individual ones and economy measures - especially more efficient use of electricity. It is a question of thinking of the system as a whole. Methane is another factor which contributes to the greenhouse effect. Methane emissions can also be avoided, or reduced, by system-thinking. System-thinking is, for instance, not ro deposit combustible waste but to use it as an energy source. And why not produce electricity by using methane from existing landfill sites. Electrical energy is the most useful form of energy. Therefore, electricity should not, as a principal rule, be used for heating, or as process energy. The fact that energy-efficiency and emission of greenhouse gases are interrelated is shown in the following two examples. 1. Only about 25% of the energy content in extracted coal will reach the consumers as electricity when the production takes place in an ordinary, coal-fires condensing power station. 2. When district heating (room-heating and hot water) is produced in a modern heat-production plant by flue-gas condensation, about 90% of the energy is utilised for heating purposes. To obtain an overall picture of the amount of energy used for a purpose, e.g. heating or electricity, you must view the entire process from extraction to final use. Such a picture can show the energy efficiency and what losses arise. Efficiency measures can reduce the energy bill. They can also reduce pollution, greenhouse gases among other things. Examples will be given in this paper of energy

  5. Primordial Noble Gases from Earth's Core

    Wang, K.; Lu, X.; Brodholt, J. P.

    2016-12-01

    Recent partitioning experiment suggests helium is more compatible in iron melt than in molten silicates at high pressures (> 10 GPa) (1), thus provide the possibility of the core as being the primordial noble gases warehouse that is responsible for the high primordial/radiogenic noble gas isotopic ratios observed in plume-related basalts. However, the possible transportation mechanism of the noble gases from the core to the overlying mantle is still ambiguous, understanding how this process would affect the noble gas isotopic characteristics of the mantle is critical to validate this core reservoir model. As diffusion is a dominant mass transport process that plays an important role in chemical exchange at the core-mantle boundary (CMB), we have determined the diffusion coefficients of helium, neon and argon in major lower mantle minerals, i.e. periclase (MgO), bridgemanite (MgSiO3-Pv) and post-perovskite (MgSiO3-PPv), by first-principles calculation based on density functional theory (DFT). As expected, the diffusion rate of helium is the fastest at the CMB, which is in the range of 3 × 10-10 to 1 × 10-8 m2/s. The neon diffusion is slightly slower, from 5 × 10-10 to 5 × 10-9 m2/s. Argon diffuses slowest at the rate from 1 × 10-10 to 2 × 10-10 m2/s. We have further simulated the evolution of noble gas isotopic ratios in the mantle near the CMB. Considering its close relationship with the mantle plumes and very likely to be the direct source of "hot-spot" basalts, we took a close investigation on the large low-shear-velocity provinces (LLSVPs). Under reasonable assumptions based on our diffusion parameters, the modelling results indicate that LLSVP is capable of generating all the noble gas isotope signals, e.g., 3He/4He = 55 Ra, 3He/22Ne = 3.1, 3He/36Ar = 0.82, 40Ar/36Ar = 9500, that are in good agreement with the observed values in "hot-spot" basalts (2). Therefore, this core-reservior hypothesis is a self-consistent model that can fits in multiple noble gas

  6. Screening for oral cancer.

    Jitender, Solanki; Sarika, Gupta; Varada, Hiremath R; Omprakash, Yadav; Mohsin, Khan

    2016-11-01

    Oral cancer is considered as a serious health problem resulting in high morbidity and mortality. Early detection and prevention play a key role in controlling the burden of oral cancer worldwide. The five-year survival rate of oral cancer still remains low and delayed diagnosis is considered as one of the major reasons. This increases the demand for oral screening. Currently, screening of oral cancer is largely based on visual examination. Various evidence strongly suggest the validity of visual inspection in reducing mortality in patients at risk for oral cancer. Simple visual examination is accompanied with adjunctive techniques for subjective interpretation of dysplastic changes. These include toluidine blue staining, brush biopsy, chemiluminescence and tissue autofluorescence. This review highlights the efficacy of various diagnostic methods in screening of oral cancer. © 2016 Old City Publishing, Inc.

  7. Which climate gases is it the most important to reduce?

    Godal, Odd; Fuglestvedt, Jan

    2002-01-01

    If the Kyoto Protocol had used another method for comparing the various climate gases, Norway might have had to implement more and more expensive measures. The selection of methods may be important for the making of new agreements after Kyoto. Calculations show the importance of the comparison methods for the various climate gases in negotiating new climate agreements. The Kyoto Protocol regulates the total emission of climate gases carbon dioxide (CO 2 ), methane (CH 4 ), laughing gas (N 2 O) and sulphur hexafluoride (SF 6 ), and halo fluoro carbons and perfluoro carbon. It is up to each country to choose which of these gases to concentrate on, and a tool is therefore needed to compare the effects of the various gases. In the Kyoto agreement, this is done by means of the global warming potential (GWP) of each gas over a period of 100 years. But different climate gases have different atmospheric residence times and it is not evident how the gases must be compared. Reducing the emission of methane has a strong and short-term effect while reducing the emission of carbon dioxide has a weaker but more lasting effect. Researchers have suggested other ways of comparison than the one used in the Kyoto Protocol. Among other things one may calculate the global warming potential for another time horizon than 100 years. Researchers at Cicero have investigated the consequences of two other ways of weighing climate gases: GWP(20) with time horizon of 20 years gives more weight to short-lived gases like methane, while GWP(500) with a time horizon of 500 years is more favourable to the long-lived gases. To see how much the selection of comparing method means in practice, the consequences for Norway using GWP(20) or GWP(500), have been calculated

  8. Oral biopsy: Oral pathologist′s perspective

    K L Kumaraswamy

    2012-01-01

    Full Text Available Many oral lesions may need to be diagnosed by removing a sample of tissue from the oral cavity. Biopsy is widely used in the medical field, but the practice is not quite widespread in dental practice. As oral pathologists, we have found many artifacts in the tissue specimen because of poor biopsy technique or handling, which has led to diagnostic pitfalls and misery to both the patient and the clinician. This article aims at alerting the clinicians about the clinical faults arising preoperatively, intraoperatively and postoperatively while dealing with oral biopsy that may affect the histological assessment of the tissue and, therefore, the diagnosis. It also reviews the different techniques, precautions and special considerations necessary for specific lesions.

  9. Subnanosecond breakdown in high-pressure gases

    Naidis, George V.; Tarasenko, Victor F.; Babaeva, Natalia Yu; Lomaev, Mikhail I.

    2018-01-01

    Pulsed discharges in high-pressure gases are of considerable interest as sources of nonequilibrium plasma for various technological applications: pollution control, pumping of laser media, plasma-assisted combustion, etc. Recently, attention has been attracted to the use of subnanosecond voltage fronts, producing diffuse discharges with radii of several millimeters. Such plasma structures, similar to pulsed glow discharges, are of special interest for applications due to quasi-uniformity of plasma parameters in relatively large gas volumes. This review presents the results of experimental and computational study of subnanosecond diffuse discharge formation. A description of generators of short high-voltage pulses with subnanosecond fronts and of discharge setups is given. Diagnostic methods for the measurement of various discharge parameters with high temporal and spatial resolution are described. Obtained experimental data on plasma properties for a wide range of governing factors are discussed. A review of various theoretical approaches used for computational study of the dynamics and structure of fast ionization waves is given; the applicability of conventional fluid streamer models for simulation of subnanosecond ionization waves is discussed. Calculated spatial-temporal profiles of plasma parameters during streamer propagation are presented. The efficiency of subnanosecond discharges for the production of reactive species is evaluated. On the basis of the comparison of simulation results and experimental data the effects of various factors (voltage rise time, polarity, etc.) on discharge characteristics are revealed. The major physical phenomena governing the properties of subnanosecond breakdown are analyzed.

  10. Beneficial Effects of Environmental Gases: Health Prospective

    Hussein, A.Z.; IBrahim, M.S.; Zakaria, Kh.M.

    2009-01-01

    Radioactive radon gas is widely considered to be a health hazard by environmental agencies in the United States and in Europe. Yet despite the warnings of these agencies, thousands of people annually expose themselves to radon for therapeutic purposes, in facilities ranging from rustic old mines, to upscale spas and clinics. The inert natural radioactive gas radon has been used since the beginning of the century in the treatment of rheumatic diseases. In many places in the world, radon is used for therapeutic purposes for various diseases. Radon inhalation is applied in a thermal gallery with atmospheric radon concentrations up to 100 kBq/m3, elevated temperature up to 41 EC , and humidity close to 100%, or in the form of radon baths where Rn is emanated from water with high natural Rn activity. Frequently, a combination of both treatment procedures is applied. Evidence from empirical experience and from clinical observational studies suggests that radon has analgesic, anti inflammatory and immune-stimulating effects. Ozone is one of nature's most powerful oxidants. It increases the effectiveness of the antioxidant enzyme system, which scavenge excess free radicals in the body. It is used in water purification and sewage treatment and is now being applied medically to treat many diseases from wounds and colitis to cancer, stroke and AIDS. According to the dosage and concentration range, medical ozone is a pharmaceutical agent that exerts specific properties and a well-defined range of efficacy. This paper describes the medical application of environmental gases: radon and ozone

  11. Collision Statistics of Driven Polydisperse Granular Gases

    Chen Zhiyuan; Zhang Duanming; Yang Fengxia; Guo Xinping; Li Zhongming

    2008-01-01

    We present a dynamical model of two-dimensional polydisperse granular gases with fractal size distribution, in which the disks are subject to inelastic mutual collisions and driven by standard white noise. The inhomogeneity of the disk size distribution can be measured by a fractal dimension d f . By Monte Carlo simulations, we have mainly investigated the effect of the inhomogeneity on the statistical properties of the system in the same inelasticity case. Some novel results are found that the average energy of the system decays exponentially with a tendency to achieve a stable asymptotic value, and the system finally reaches a nonequilibrium steady state after a long evolution time. Furthermore, the inhomogeneity has great influence on the steady-state statistical properties. With the increase of the fractal dimension d f , the distributions of path lengths and free times between collisions deviate more obviously from expected theoretical forms for elastic spheres and have an overpopulation of short distances and time bins. The collision rate increases with d f , but it is independent of time. Meanwhile, the velocity distribution deviates more strongly from the Gaussian one, but does not demonstrate any apparent universal behavior

  12. Landau damping in trapped Bose condensed gases

    Jackson, B; Zaremba, E [Department of Physics, Queen' s University, Kingston, ON K7L 3N6 (Canada)

    2003-07-01

    We study Landau damping in dilute Bose-Einstein condensed gases in both spherical and prolate ellipsoidal harmonic traps. We solve the Bogoliubov equations for the mode spectrum in both of these cases, and calculate the damping by summing over transitions between excited quasiparticle states. The results for the spherical case are compared to those obtained in the Hartree-Fock (HF) approximation, where the excitations take on a single-particle character, and excellent agreement between the two approaches is found. We have also taken the semiclassical limit of the HF approximation and obtain a novel expression for the Landau damping rate involving the time-dependent self-diffusion function of the thermal cloud. As a final approach, we study the decay of a condensate mode by making use of dynamical simulations in which both the condensate and thermal cloud are evolved explicitly as a function of time. A detailed comparison of all these methods over a wide range of sample sizes and trap geometries is presented.

  13. Nozzle flow calculation for real gases

    Bier, K.; Ehrler, F.; Hartz, U.; Kissau, G.

    1977-01-01

    The flow of CHF 2 Cl vapor (refrigerant R 22) through a Laval nozzle of annular geometry has been investigated in the region near the saturation line with stagnation pressures up to 85 per cent of the critical pressure. Static pressure profiles measured along the nozzle axis were found in good agreement with profiles calculated for one-dimensional isentropic flow of the real gas the thermal properties of which were derived from an equation of state proposed previously by Rombusch. Minor deviations between measured and calculated static pressure curves occur in the supersonic part of the mozzle, especially when supersaturated states of the vapour are passed. These deviations can be attributed to uncertainties in the calculation of the enthalpy and to a small influence of the static pressure probe. An additional investigation was concerned with an approximate calculation of the nozzle flow of real gases. In this approximation the well known relations of ideal gas dynamics are applied, the ratio of specific heats for the ideal gas being replaced, however, by a suitably adapted isentropic exponent, which can be determined e.g. from measured values of the Laval pressure or of the mass flow. For pressure ratios p/po between 1 and approximately 0.1, corresponding to Mach numbers up to approximately 2.2, all the interesting properties of the investigated flow of CHF 2 Cl vapour are approximated within a few per cent. (orig.) [de

  14. Thermodesorption of gases from various vacuum materials

    Beavis, L.C.

    1979-06-01

    A number of materials are commonly used as vacuum system walls. The desorption of gases from these materials may contribute significantly to the internal pressure of an unpumped device or to the gas load which a pump must handle in a dynamic system. This report describes the thermodesorption measurements made on a number of metals (molybdenum, nickel, Kovar alloy, copper, copper-2% beryllium alloy) and two insulators (molybdenum sealing glass ceramic and high alumina ceramic). All of the materials after typical cleaning and air exposure contain considerable gas. With a long 400 0 to 500 0 vacuum bake, however, all can be cleaned sufficiently so that they will not contribute appreciable gas to their surrounding when vacuum stored at room temperature for many years. Most materials display desorption kinetics which are first order (a single bond or trap energy must be overcome for desorption). It appears that the desorption of CO from Kovar is rate limited by carbon diffusion (D 0 approx. = .4 cm 2 /s and E/sub d/ approx. = 27,000 cal/mol). The desorption of hydrogen from glass ceramic also appears to be diffusion rate limited (D 0 approx. = 1 x 10 -3 cm 2 /s and E/sub d/ approx. = 11,000 cal/mol). Carbon monoxide is the major gas desorbed from metals, except copper for which hydrogen is the major desorbing species. The insulators desorb hydrogen primarily

  15. Hydropower may produce more greenhouse gases

    Kolshus, Hans H.; Folkestad, Tonje

    2002-01-01

    According to this article, dam projects in hydropower development may lead to increased emission of greenhouse gases and may create great inconveniences for the local community. Hence it is not without problems to sponsor such projects through the Clean Development Mechanism (CDM) of the Kyoto Protocol. In many countries the great era of hydroelectric development is over and the potential is now in the developing countries. The aim of the CDM is two-fold: sustainable development in the developing countries, and cheap reduction of greenhouse gas emission from developed nations. It has been agreed upon in the climate negotiations that it is the developing country receiving the investments that shall document that the projects conform to the goal of sustainable development of that country. The concept of sustain ability is a vague one, and it is a great challenge to make it more precise so that requirements may be posed on CDM projects. This is important as projects that are suitable from a climate point of view may have undesirable environmental or social effects, which may be in conflict with the goal of sustainable development. This also pertains to hydropower. It also appears that water reservoirs are not always as clean as has been assumed

  16. Coal pyrolysis under hydrogen-rich gases

    Liao, H.; Sun, C.; Li, B.; Liu, Z. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion, Institute of Coal Chemistry

    1998-04-01

    To improve the economy of the pyrolysis process by reducing the hydrogen cost, it is suggested to use cheaper hydrogen-rich gases such as coke-oven gas (COG) or synthesis gas (SG) instead of pure hydrogen. The pyrolysis of Chinese Xianfeng lignite which was carried out with real COG and SG at 3-5 MPa, a final temperature of 650{degree}C and a heating rate of 5{degree}C/min in a 10g fixed-bed reactor is compared with coal pyrolysis with pure hydrogen and nitrogen under the same conditions. The results indicate that compared with hydropyrolysis at the same total pressure, the total conversion and tar yields from coal pyrolysis with COG and SG decreases while the unwanted water increases. However, at the same H{sub 2} partial pressure, the tar yields and yields of BBTX, PCX and naphthalene from the pyrolysis of coal with COG and SG are all significantly higher than those of hydropyrolysis. Therefore, it is possible to use COG and SG instead of pure hydrogen. 8 refs., 3 figs., 6 tabs.

  17. Brane gases in the early Universe

    Alexander, S.; Brandenberger, R.; Easson, D.

    2000-01-01

    Over the past decade it has become clear that fundamental strings are not the only fundamental degrees of freedom in string theory. D-branes are also part of the spectrum of fundamental states. In this paper we explore some possible effects of D-branes on early Universe string cosmology, starting with two key assumptions: firstly that the initial state of the Universe corresponded to a dense, hot gas in which all degrees of freedom were in thermal equilibrium, and secondly that the topology of the background space admits one-cycles. We argue by t duality that in this context the cosmological singularities are not present. We derive the equation of state of the brane gases and apply the results to suggest that, in an expanding background, the winding modes of fundamental strings will play the most important role at late times. In particular, we argue that the string winding modes will only allow four space-time dimensions to become large. The presence of brane winding modes with p>1 may lead to a hierarchy in the sizes of the extra dimensions

  18. Oral manifestations of lupus.

    Menzies, S; O'Shea, F; Galvin, S; Wynne, B

    2018-02-01

    Mucosal involvement is commonly seen in patients with lupus; however, oral examination is often forgotten. Squamous cell carcinoma arising within oral lupoid plaques has been described, emphasizing the importance of identifying and treating oral lupus. We undertook a retrospective single-centre study looking at oral findings in patients attending our multidisciplinary lupus clinic between January 2015 and April 2016. A total of 42 patients were included. The majority of patients were female (88%) and had a diagnosis of discoid lupus erythematosus (62%). Half of the patients had positive oral findings, 26% had no oral examination documented, and 24% had documented normal oral examinations. Our findings suggest that oral pathology is common in this cohort of patients. Regular oral examination is warranted to identify oral lupus and provide treatment. Associated diseases such as Sjogren's syndrome may also be identified. Patients should be encouraged to see their general dental practitioners on a regular basis for mucosal review. Any persistent ulcer that fails to respond to treatment or hard lump needs urgent histopathological evaluation to exclude malignant transformation to squamous cell carcinoma.

  19. Greenhouse effect gases (GEI) by energy consumption; Gases efecto invernadero (GEI) por consumo de energia

    Munoz Ledo C, Ramon; Bazan N, Gerardo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2003-07-01

    The purpose of this article is to present the calculation methodology of greenhouse effect gases (GEI) emissions that are produced by the power sector in Mexico, as well as to discuss its possible impact in the subject of climatic change and the possible mitigating actions to lower the amount of emissions that can be taken and, therefore, the possible climate changes. In Mexico GEI inventories have been made since 1991, year in which the National Inventory of Gases with Greenhouse Effect was obtained for year 1988. The GEI include carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), methane (CH4), nitrous oxide (NO) and volatile organic carbides that are not methane (NMVOC) and are secondary products and harmful that are obtained from the processes that turn fuels into energy (combustion). The main sources of GEI are: fixed sources (industries, residences, commerce, public services and energy transformation, such as power generation); movable sources (that include all type of transport that uses fuel). The fuels that, by their volume and efficiency, generate more emissions of GEI are crude oil, natural gas and solid biomass (firewood-cane bagasse). Any effort to reduce these emissions is very important and remarkable if it affects the consumption of these fuels. [Spanish] El proposito de este articulo es presentar la metodologia de calculo de las emisiones de los gases con efecto invernadero (GEI) que son producidos por el sector energetico en Mexico, asi como discutir su posible impacto en las cuestiones de cambio climatico y las posibles acciones de mitigacion que se pueden realizar para abatir la cantidad de emisiones y, por ende, los posibles cambios de clima. En Mexico se han realizado inventarios de GEI desde 1991, ano en que se obtuvo el Inventario Nacional de Gases con Efecto Invernadero para el ano de 1988. Los GEI comprenden al dioxido de carbono (CO2), monoxido de carbono (CO), oxidos de nitrogeno (NOx), metano (CH4), oxido nitroso (N2O) y

  20. Emission of greenhouse gases from Danish agriculture

    Olesen, J.E.; Petersen, S.O.; Fenhann, J.V.; Andersen, J.M.; Jacobsen, B.H.

    2001-01-01

    emission factors for nitrous oxide does not imply a correspondingly large uncertainty in the relative contribution of individual sources to the total emission. The different sources of nitrous oxide in the field are affected by the same mechanisms independent of location, and thus the uncertainty is mainly associated with the level of this emission in Denmark compared with other regions. In Denmark there has not previously been any concerted research effort to quantify emissions of greenhouse gases from agriculture. The existing, somewhat scattered research has mainly been a spin-off from research programmes with other main objectives. Accordingly there is no solid foundation for evaluation of neither emission levels nor mitigation options. A proposal for a research programme on emission of greenhouse gases from agriculture is therefore presented, which should provide a better basis for quantifying individual emission sources, their development over time, and the effect of reduction measures. Emphasis is given to improve our knowledge on emissions of methane and nitrous oxide, and to the possibilities of agriculture in storing carbon and in the reduction and substitution of fossil fuel use. (au)

  1. Radiation induced oral mucositis

    P S Satheesh Kumar

    2009-01-01

    Full Text Available Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii who also received concomitant chemotherapy; (iii who received a total dose over 5,000 cGy; and (iv who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene

  2. Temporal dynamics of Bose-condensed gases

    Trujillo Martinez, Mauricio

    2014-03-19

    We perform a detailed quantum dynamical study of non-equilibrium trapped, interacting Bose-condensed gases. We investigate Josephson oscillations between interacting Bose-Einstein condensates confined in a finite size double-well trap and the non-trivial time evolution of a coherent state placed at the center of a two dimensional optical lattice. For the Josephson oscillations three time scales appear. We find that Josephson junction can sustain multiple undamped oscillations up to a characteristic time scale τ{sub c} without exciting atoms out of the condensates. Beyond the characteristic time scale τ{sub c} the dynamics of the junction are governed by fast, non-condensed particles assisted Josephson tunnelling as well as the collisions between non-condensed particles. In the non-condensed particles dominated regime we observe strong damping of the oscillations due to inelastic collisions, equilibrating the system leading to an effective loss of details of the initial conditions. In addition, we predict that an initially self-trapped BEC state will be destroyed by these fast dynamics. The time evolution of a coherent state released at the center of a two dimensional optical lattice shows a ballistic expansion with a decreasing expansion velocity for increasing two-body interactions strength and particle number. Additionally, we predict that if the two-body interactions strength exceeds a certain value, a forerunner splits up from the expanding coherent state. We also observe that this system, which is prepared far from equilibrium, can evolve to a quasistationary non-equilibrium state.

  3. High order harmonic generation in rare gases

    Budil, Kimberly Susan [Univ. of California, Davis, CA (United States)

    1994-05-01

    The process of high order harmonic generation in atomic gases has shown great promise as a method of generating extremely short wavelength radiation, extending far into the extreme ultraviolet (XUV). The process is conceptually simple. A very intense laser pulse (I ~1013-1014 W/cm2) is focused into a dense (~1017 particles/cm3) atomic medium, causing the atoms to become polarized. These atomic dipoles are then coherently driven by the laser field and begin to radiate at odd harmonics of the laser field. This dissertation is a study of both the physical mechanism of harmonic generation as well as its development as a source of coherent XUV radiation. Recently, a semiclassical theory has been proposed which provides a simple, intuitive description of harmonic generation. In this picture the process is treated in two steps. The atom ionizes via tunneling after which its classical motion in the laser field is studied. Electron trajectories which return to the vicinity of the nucleus may recombine and emit a harmonic photon, while those which do not return will ionize. An experiment was performed to test the validity of this model wherein the trajectory of the electron as it orbits the nucleus or ion core is perturbed by driving the process with elliptically, rather than linearly, polarized laser radiation. The semiclassical theory predicts a rapid turn-off of harmonic production as the ellipticity of the driving field is increased. This decrease in harmonic production is observed experimentally and a simple quantum mechanical theory is used to model the data. The second major focus of this work was on development of the harmonic "source". A series of experiments were performed examining the spatial profiles of the harmonics. The quality of the spatial profile is crucial if the harmonics are to be used as the source for experiments, particularly if they must be refocused.

  4. Concept of Heat Recovery from Exhaust Gases

    Bukowska, Maria; Nowak, Krzysztof; Proszak-Miąsik, Danuta; Rabczak, Sławomir

    2017-10-01

    The theme of the article is to determine the possibility of waste heat recovery and use it to prepare hot water. The scope includes a description of the existing sample of coal-fired boiler plant, the analysis of working condition and heat recovery proposals. For this purpose, a series of calculations necessary to identify the energy effect of exhaust temperature decreasing and transferring recovery heat to hot water processing. Heat recover solutions from the exhaust gases channel between boiler and chimney section were proposed. Estimation for the cost-effectiveness of such a solution was made. All calculations and analysis were performed for typical Polish conditions, for coal-fired boiler plant. Typicality of this solution is manifested by the volatility of the load during the year, due to distribution of heat for heating and hot water, determining the load variation during the day. Analysed system of three boilers in case of load variation allows to operational flexibility and adaptation of the boilers load to the current heat demand. This adaptation requires changes in the operating conditions of boilers and in particular assurance of properly conditions for the combustion of fuel. These conditions have an impact on the existing thermal loss and the overall efficiency of the boiler plant. On the boiler plant efficiency affects particularly exhaust gas temperature and the excess air factor. Increasing the efficiency of boilers plant is possible to reach by following actions: limiting the excess air factor in coal combustion process in boilers and using an additional heat exchanger in the exhaust gas channel outside of boilers (economizer) intended to preheat the hot water.

  5. Preparing for the regulation of greenhouse gases

    Ezekiel, R.; Wilson, P.

    2001-01-01

    The Earth is warming, and this belief is shared by the leading scientists that sit on the Intergovernmental Panel on Climate Change, where it is expected that the average surface temperature of the Earth will rise 2.5 to 10.4 degrees Fahrenheit between 1990 and 2100. It is felt that the main culprit is greenhouse gas emissions such as carbon dioxide. The Kyoto Protocol was adopted in 1992 with the aim of reducing greenhouse gas emissions to specified targets below 1990 levels by 2012. For Canada, this commitment is a reduction to 6 per cent below 1990 levels. To avoid penalizing a country that adopts greenhouse gas regulations where the neighbouring country does not follow, negotiations are being held at the international level in an attempt to keep everyone on a level playing field. The United States recently decided not to pursue a cap on greenhouse gas emissions, which could seriously jeopardize the effectiveness of the Kyoto Protocol. The authors examined what the future looks like, in terms of policy options and market-based instruments. In the next section, they discussed the preparations for the regulation of greenhouse gases. The topics reviewed were carbon taxes, command and control regulation, emissions trading, contracts and baseline protection. Canada's baseline protection initiative (BPI) process was closely examined, and identified what reductions are eligible and touched upon ownership issues. The authors concluded that it might be prudent for emitters in Canada to prepare for a variety of regulatory scenarios, as there are a number of uncertainties remaining. Emissions trading must be carefully documented

  6. Radioactive rare gases emission at underground nuclear explosions

    Dubasov, Yu.V.

    2016-01-01

    The examples of radioactive rare gases emission at underground nuclear explosions conducted in the USSR on the Novaya Zemlya and Semipalatinsk test sites are considered. It is pointed out that in the case of evasive explosion in vertical wells without apparent radioactive gases emission the samples of subsurface gas must contain the traces of radioactive rare gases. Under the inspection of evasive explosion in horizontal workings of rock massif, one should guided by the analysis of atmospheric air samples in the inspected area [ru

  7. Effective collision frequency of electrons in noble gases

    Baille, P.; Chang, J.-S.; Claude, A.; Yau, A.W.; Hobson, R.M.; Ogram, G.L.

    1981-01-01

    The electron-neutral collision frequency in the noble gases has been calculated using recent numerical results for momentum transfer cross sections by assuming a Maxwellian distribution of electron velocities. In all these gases, except for argon, good agreement is obtained with most previously published experimental and theoretical data. Mean free path, mobilities and diffusion coefficients are also calculated from the resulting effective collision frequencies. The empirical formulae are presented for an electron temperature dependence of the electron-neutral collision frequency for all noble gases up to Tsub(e) < approximately 25.000 K. (author)

  8. Time-dependent behavior of positrons in noble gases

    Wadehra, J.M.

    1990-01-01

    Both equilibrium and nonequilibrium behaviors of positrons in several noble gases are reviewed. Our novel procedure for obtaining the time-dependent behavior of various swarm parameters -- such as the positron drift velocity, average positron energy, positron annihilation rate (or equivalently Z eff ) etc. -- for positrons in pure ambient gases subjected to external electrostatic fields is described. Summaries of time-dependent as well as electric field-dependent results for positron swarms in various noble gases are presented. New time-dependent results for positron swarms in neon are also described in detail. 36 refs., 4 figs., 3 tabs

  9. Teledetección de Gases mediante Sensores Infrarrojo (IR)

    López Martínez, Fernando

    2008-01-01

    El LIR- UC3M, Laboratorio de Sensores IR de la Universidad Carlos III, ha desarrollado técnicas de análisis multi e hiperespectral IR para la teledetección de gases. Ofrece el diseño de sensores específicos para determinar la presencia de gases y su concentración. La práctica totalidad de los gases (CO2, CO, NO2, O3, HC o NH, etc.) implicados en la seguridad industrial, ambiental o militar pueden ser detectados. Se busca empresas o centros interesados en el uso de sensores de aplicación e...

  10. Process for scavenging hydrogen sulfide from hydrocarbon gases

    Fox, I.

    1981-01-01

    A process for scavenging hydrogen sulfide from hydrocarbon gases utilizes iron oxide particles of unique chemical and physical properties. These particles have large surface area, and are comprised substantially of amorphous Fe 2 O 3 containing a crystalline phase of Fe 2 O 3 , Fe 3 O 4 and combinations thereof. In scavenging hydrogen sulfide, the iron oxide particles are suspended in a liquid which enters into intimate mixing contact with hydrocarbon gases; the hydrogen sulfide is reacted at an exceptional rate and only acid-stable reaction products are formed. Thereafter, the sweetened hydrocarbon gases are collected

  11. Cryogenic method for measuring nuclides and fission gases

    Perdue, P.T.; Haywood, F.F.

    1980-05-02

    A cryogenic method is provided for determining airborne gases and particulates from which gamma rays are emitted. A special dewar counting vessel is filled with the contents of the sampling flask which is immersed in liquid nitrogen. A vertically placed sodium-iodide or germanium-lithium gamma-ray detector is used. The device and method are of particular use in measuring and identifying the radioactive noble gases including emissions from coal-fired power plants, as well as fission gases released or escaping from nuclear power plants.

  12. 75 FR 74773 - Mandatory Reporting of Greenhouse Gases: Additional Sources of Fluorinated GHGs

    2010-12-01

    ...-mechanical systems (MEMS) manufacturing facilities. Fluorinated Gas Production....... 325120 Industrial gases... of Industrial Greenhouse Gases. Electrical Equipment Use General Stationary Fuel Combustion. Imports and Exports of Fluorinated Suppliers of Industrial Greenhouse GHGs Inside Pre-charged Equipment Gases...

  13. Oral microbiota and cancer

    Meurman, Jukka H.

    2010-01-01

    Inflammation caused by infections may be the most important preventable cause of cancer in general. However, in the oral cavity the role of microbiota in carcinogenesis is not known. Microbial populations on mouth mucosa differ between healthy and malignant sites and certain oral bacterial species have been linked with malignancies but the evidence is still weak in this respect. Nevertheless, oral microorganisms inevitably up-regulate cytokines and other inflammatory mediators that affect the...

  14. Towards understanding oral health.

    Zaura, Egija; ten Cate, Jacob M

    2015-01-01

    During the last century, dental research has focused on unraveling the mechanisms behind various oral pathologies, while oral health was typically described as the mere absence of oral diseases. The term 'oral microbial homeostasis' is used to describe the capacity of the oral ecosystem to maintain microbial community stability in health. However, the oral ecosystem itself is not stable: throughout life an individual undergoes multiple physiological changes while progressing through infancy, childhood, adolescence, adulthood and old age. Recent discussions on the definition of general health have led to the proposal that health is the ability of the individual to adapt to physiological changes, a condition known as allostasis. In this paper the allostasis principle is applied to the oral ecosystem. The multidimensionality of the host factors contributing to allostasis in the oral cavity is illustrated with an example on changes occurring in puberty. The complex phenomenon of oral health and the processes that prevent the ecosystem from collapsing during allostatic changes in the entire body are far from being understood. As yet individual components (e.g. hard tissues, microbiome, saliva, host response) have been investigated, while only by consolidating these and assessing their multidimensional interactions should we be able to obtain a comprehensive understanding of the ecosystem, which in turn could serve to develop rational schemes to maintain health. Adapting such a 'system approach' comes with major practical challenges for the entire research field and will require vast resources and large-scale multidisciplinary collaborations. 2015 S. Karger AG, Basel

  15. Global Oral Health Inequalities

    Garcia, I.; Tabak, L.A.

    2011-01-01

    Despite impressive worldwide improvements in oral health, inequalities in oral health status among and within countries remain a daunting public health challenge. Oral health inequalities arise from a complex web of health determinants, including social, behavioral, economic, genetic, environmental, and health system factors. Eliminating these inequalities cannot be accomplished in isolation of oral health from overall health, or without recognizing that oral health is influenced at multiple individual, family, community, and health systems levels. For several reasons, this is an opportune time for global efforts targeted at reducing oral health inequalities. Global health is increasingly viewed not just as a humanitarian obligation, but also as a vehicle for health diplomacy and part of the broader mission to reduce poverty, build stronger economies, and strengthen global security. Despite the global economic recession, there are trends that portend well for support of global health efforts: increased globalization of research and development, growing investment from private philanthropy, an absolute growth of spending in research and innovation, and an enhanced interest in global health among young people. More systematic and far-reaching efforts will be required to address oral health inequalities through the engagement of oral health funders and sponsors of research, with partners from multiple public and private sectors. The oral health community must be “at the table” with other health disciplines and create opportunities for eliminating inequalities through collaborations that can harness both the intellectual and financial resources of multiple sectors and institutions. PMID:21490232

  16. Oral microbiota and cancer

    Jukka H. Meurman

    2010-08-01

    Full Text Available Inflammation caused by infections may be the most important preventable cause of cancer in general. However, in the oral cavity the role of microbiota in carcinogenesis is not known. Microbial populations on mouth mucosa differ between healthy and malignant sites and certain oral bacterial species have been linked with malignancies but the evidence is still weak in this respect. Nevertheless, oral microorganisms inevitably up-regulate cytokines and other inflammatory mediators that affect the complex metabolic pathways and may thus be involved in carcinogenesis. Poor oral health associates statistically with prevalence of many types of cancer, such as pancreatic and gastrointestinal cancer. Furthermore, several oral micro-organisms are capable of converting alcohol to carcinogenic acetaldehyde which also may partly explain the known association between heavy drinking, smoking, poor oral health and the prevalence of oral and upper gastrointestinal cancer. A different problem is the cancer treatment-caused alterations in oral microbiota which may lead to the emergence of potential pathogens and subsequent other systemic health problems to the patients. Hence clinical guidelines and recommendations have been presented to control oral microbiota in patients with malignant disease, but also in this area the scientific evidence is weak. More controlled studies are needed for further conclusion.

  17. African Journal of Oral Health Sciences

    The African Journal of Oral Health Sciences is devoted to research into oral diseases and encourages a multidisciplinary approach. Emphasis is on oral pathology, oral microbiology, oral medicine, oral physiology and biochemistry and related clinical sciences.

  18. Oral candidosis in relation to oral immunity.

    Feller, L; Khammissa, R A G; Chandran, R; Altini, M; Lemmer, J

    2014-09-01

    Symptomatic oral infection with Candida albicans is characterized by invasion of the oral epithelium by virulent hyphae that cause tissue damage releasing the inflammatory mediators that initiate and sustain local inflammation. Candida albicans triggers pattern-recognition receptors of keratinocytes, macrophages, monocytes and dendritic cells, stimulating the production of IL-1β, IL-6 and IL-23. These cytokines induce the differentiation of Th17 cells and the generation of IL-17- and/or IL-22-mediated antifungal protective immuno-inflammatory responses in infected mucosa. Some immune cells including NKT cells, γδ T cells and lymphoid cells that are innate to the oral mucosa have the capacity to produce large quantities of IL-17 in response to C. albicans, sufficient to mediate effective protective immunity against C. albicans. On the other hand, molecular structures of commensal C. albicans blastoconidia, although detected by pattern-recognition receptors, are avirulent, do not invade the oral epithelium, do not elicit inflammatory responses in a healthy host, but induce regulatory immune responses that maintain tissue tolerance to the commensal fungi. The type, specificity and sensitivity of the protective immune response towards C. albicans is determined by the outcome of the integrated interactions between the intracellular signalling pathways of specific combinations of activated pattern-recognition receptors (TLR2, TLR4, Dectin-1 and Dectin-2). IL-17-mediated protective immune response is essential for oral mucosal immunity to C. albicans infection. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Desulfurization of chemical waste gases and flue gases with economic utilization of air pollutants

    Asperger, K.; Wischnewski, W.

    1983-09-01

    The technological state of recovery of sulfur dioxide from waste and flue gases in the GDR is discussed. Two examples of plants are presented: a pyrosulfuric acid plant in Coswig, recovering sulfur dioxide from gases by absorption with sodium hydroxide, followed by catalytic oxidation to sulfur trioxide, and a plant for waste sulfuric acid recovery from paraffin refining, where the diluted waste acid is sprayed into a furnace and recovered by an ammonium-sulfite-bisulfite solution from the combustion gas (with 4 to 10% sulfur dioxide content). Investment and operation costs as well as profits of both plants are given. Methods employed for power plant flue gas desulfurization in major industrial countries are further assessed: about 90% of these methods uses wet flue gas scrubbing with lime. In the USA flue gas from 25,000 MW of power plant capacity is desulfurized. In the USSR, a 35,000 m/sup 3//h trial plant at Severo-Donetzk is operating using lime, alkali and magnesite. At the 150 MW Dorogobush power plant in the USSR a desulfurization plant using a cyclic ammonia process is under construction.

  20. Process for the removal of acid forming gases from exhaust gases

    Chang, S.G.; Liu, D.K.

    1992-11-17

    Exhaust gases are treated to remove NO or NO[sub x] and SO[sub 2] by contacting the gases with an aqueous emulsion or suspension of yellow phosphorus preferably in a wet scrubber. The pressure is not critical, and ambient pressures are used. Hot water temperatures are best, but economics suggest about 50 C is attractive. The amount of yellow phosphorus used will vary with the composition of the exhaust gas, less than 3% for small concentrations of NO, and 10% or higher for concentrations above say 1000 ppm. Similarly, the pH will vary with the composition being treated, and it is adjusted with a suitable alkali. For mixtures of NO[sub x] and SO[sub 2], alkalis that are used for flue gas desulfurization are preferred. With this process, 100% of the by-products created are usable, and close to 100% of the NO or NO[sub x] and SO[sub 2] can be removed in an economic fashion. 9 figs.

  1. Trace Gases, CO2, Climate, and the Greenhouse Effect.

    Aubrecht, Gordon J., II

    1988-01-01

    Reports carbon dioxide and other trace gases can be the cause of the Greenhouse Effect. Discusses some effects of the temperature change and suggests some solutions. Included are several diagrams, graphs, and a table. (YP)

  2. The application of isotope techniques to the analysis of gases

    Leonhardt, J.W.; Grosse, H.J.; Popp, P.; Thuemmel, H.W.

    1978-01-01

    The development of devices for the detection of nuclear radiation has also led to systems permitting concentrations of gaseous components in gases or mixtures of gases to be determined with the aid of ionizing radiation. Such systems, which use either the ionization of gases in connection with recombination processes or the multiplication of charged particles, or the excitation of gases by means of α,β,γ or X-rays, are described. The most frequently used ionization detectors (electron capture detectors, aerosol ionization analysers, cross-section detectors, noble gas detectors and electron mobility detectors) are characterized with reference to their properties and main fields of application. It is shown that as a result of the development of sensitive energy-resolving detectors the possibilities for the utilization of excitation processes for gas analysis are increasing. The prospects for ionization detectors and systems based on the excitation of characteristic X-rays are discussed. (author)

  3. Quantum gases finite temperature and non-equilibrium dynamics

    Szymanska, Marzena; Davis, Matthew; Gardiner, Simon

    2013-01-01

    The 1995 observation of Bose-Einstein condensation in dilute atomic vapours spawned the field of ultracold, degenerate quantum gases. Unprecedented developments in experimental design and precision control have led to quantum gases becoming the preferred playground for designer quantum many-body systems. This self-contained volume provides a broad overview of the principal theoretical techniques applied to non-equilibrium and finite temperature quantum gases. Covering Bose-Einstein condensates, degenerate Fermi gases, and the more recently realised exciton-polariton condensates, it fills a gap by linking between different methods with origins in condensed matter physics, quantum field theory, quantum optics, atomic physics, and statistical mechanics. Thematically organised chapters on different methodologies, contributed by key researchers using a unified notation, provide the first integrated view of the relative merits of individual approaches, aided by pertinent introductory chapters and the guidance of ed...

  4. Laser-aided diagnostics of plasmas and gases

    Muraoka, K

    2000-01-01

    Updated and expanded from the original Japanese edition, Laser-Aided Diagnostics of Gases and Plasmas takes a unique approach in treating laser-aided diagnostics. The book unifies the subject by joining applications instead of describing each application as a totally separate system. In taking this approach, it highlights the relative strengths of each method and shows how they can complement each other in the study of gases and plasmas.The first part of the book presents a general introduction to the laser-aided study of gases and plasmas, including the various principles and hardware needed for each method, while the second part describes the applications of each general system in detail.Beneficial to a wide spectrum of academic and industrial researchers, this book provides a solid examination of the various options and methods available when involved in the analysis and diagnostics of gases and plasmas.

  5. Molecular model for solubility of gases in flexible polymers

    Neergaard, Jesper; Hassager, Ole; Szabo, Peter

    1999-01-01

    We propose a model for a priori prediction of the solubility of gases in flexible polymers. The model is based on the concept of ideal solubility of gases in liquids. According to this concept, the mole fraction of gases in liquids is given by Raoult's law with the total pressure and the vapor...... pressure of the gas, where the latter may have to be extrapolated. However, instead of considering each polymer molecule as a rigid structure, we estimate the effective number of degrees of freedom from an equivalent freely jointed bead-rod model for the flexible polymer. In this model, we associate...... the length of the rods with the molecular weight corresponding to a Kuhn step. The model provides a tool for crude estimation of the gas solubility on the basis of only the monomer unit of the polymer and properties of the gas. A comparison with the solubility data for several gases in poly...

  6. Photoacoustic absorption spectra of atmospheric gases near 7603 cm-1

    Lawton, S.A.; Bragg, S.L.

    1984-01-01

    Absorption spectra of carbon monoxide, water vapor, memane, and ammonia are presented as part of an effort to determine absolute absorption cross sections for some atmospheric gases at the iodine laser wavelength

  7. Conference report for nuclear fusion phenomena in ionized gases

    Porkolab, M.

    1975-10-01

    A summary of the Conference on Phenomena in Ionized Gases, held in Eindhoven, The Netherlands, is given. In particular, the format of the conference and the content of the review papers are summarized

  8. Device for removing radioactive solids in wet gases

    Ootsuka, Katsuyuki; Miyo, Hiroaki.

    1981-01-01

    Purpose: To enable removal and decontamination of radioactive solids in wet gases simply, easily and securely by removing radioactive solids in gases by filteration and applying microwaves to filters to evaporate condensed moistures. Constitution: Objects to be heated such as solutions, sludges and solids containing radioactive substances are placed in an evaporation vessel and a microwave generator is operated. Microwaves are applied to the objects in the evaporation vessel through a shielding plate and filters. The objects are evaporated and exhausted gases are passed through the filters and sent to an exhaust gas processing system by way of an exhaust gas pipe. Condensed moistures deposited on the filters which would otherwise cause cloggings are evaporated being heated by the microwaves to prevent cloggings. The number of stages for the filters may optionally be adjusted depending on the extent of the contamination in the exhaust gases. (Kawakami, Y.)

  9. THE USE OF BIOFILTERS FOR DEODORISATION OF THE NOXIOUS GASES

    Monika Wierzbińska

    2015-01-01

    Full Text Available One of the methods of deodorization of noxious gases is biofiltration. This method consists of pollutants biodegradation by using micro-organisms, what leads to the formation of nontoxic and innoxious compounds. In comparison with conventional techniques, bio-filtration requires lower investments and exploitation costs, moreover it is nature friendly. This technique is still developing. Scientists have carried out research on the optimization of biofiltration process, biofilters and selecting parameters of purified gases or improving the method of efficiency. However, industrial application of biofilters is still difficult for many reasons. In this paper we present the mechanism of biofiltration process, the parameters and conditions which have to be fulfilled by purified gases, installation structure for gases biofiltration, application field of this method and specific example of exploited biofilters, including practical operational guidelines.

  10. Sarcoidosis: Oral and extra-oral manifestation

    Sanjay Gupta

    2015-01-01

    Full Text Available Sarcoidosis is a multisystem granulomatous disease, which is usually associated with the formation of noncaseating granulomas in affected tissues and organs. It is mostly present with bilateral hilar lymphadenopathy, pulmonary infiltration, ocular, and cutaneous lesions. Oral manifestations of this disease are relatively rare. The present case report shows a 40-year-old male with lesions in the soft tissue of oral cavity (buccal mucosa, gingiva, and palate and a diagnosis of sarcoidosis was established following hematological, biochemical and pulmonary function tests, chest radiograph, and histopathological investigation.

  11. Hot gas flow cell for optical measurements on reactive gases

    Grosch, Helge; Fateev, Alexander; Nielsen, Karsten Lindorff

    2013-01-01

    A new design is presented for a gas flow cell for reactive gases at high temperatures. The design features three heated sections that are separated by flow windows. This design avoids the contact of reactive gases with the material of the exchangeable optical windows. A gas cell with this design ......-resolution measurements are presented for the absorption cross-section of sulfur dioxide (SO2) in the UV range up to 773 K (500 degrees C)...

  12. ACTRIS Aerosol, Clouds and Trace Gases Research Infrastructure

    Pappalardo Gelsomina

    2018-01-01

    The Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS) is a distributed infrastructure dedicated to high-quality observation of aerosols, clouds, trace gases and exploration of their interactions. It will deliver precision data, services and procedures regarding the 4D variability of clouds, short-lived atmospheric species and the physical, optical and chemical properties of aerosols to improve the current capacity to analyse, understand and predict past, current and future evo...

  13. ACTRIS Aerosol, Clouds and Trace Gases Research Infrastructure

    Pappalardo Gelsomina

    2018-01-01

    Full Text Available The Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS is a distributed infrastructure dedicated to high-quality observation of aerosols, clouds, trace gases and exploration of their interactions. It will deliver precision data, services and procedures regarding the 4D variability of clouds, short-lived atmospheric species and the physical, optical and chemical properties of aerosols to improve the current capacity to analyse, understand and predict past, current and future evolution of the atmospheric environment.

  14. ACTRIS Aerosol, Clouds and Trace Gases Research Infrastructure

    Pappalardo, Gelsomina

    2018-04-01

    The Aerosols, Clouds and Trace gases Research Infrastructure (ACTRIS) is a distributed infrastructure dedicated to high-quality observation of aerosols, clouds, trace gases and exploration of their interactions. It will deliver precision data, services and procedures regarding the 4D variability of clouds, short-lived atmospheric species and the physical, optical and chemical properties of aerosols to improve the current capacity to analyse, understand and predict past, current and future evolution of the atmospheric environment.

  15. Electron beam treatment of simulated marine diesel exhaust gases

    Licki Janusz

    2015-09-01

    Full Text Available The exhaust gases from marine diesel engines contain high SO2 and NOx concentration. The applicability of the electron beam flue gas treatment technology for purification of marine diesel exhaust gases containing high SO2 and NOx concentration gases was the main goal of this paper. The study was performed in the laboratory plant with NOx concentration up to 1700 ppmv and SO2 concentration up to 1000 ppmv. Such high NOx and SO2 concentrations were observed in the exhaust gases from marine high-power diesel engines fuelled with different heavy fuel oils. In the first part of study the simulated exhaust gases were irradiated by the electron beam from accelerator. The simultaneous removal of SO2 and NOx were obtained and their removal efficiencies strongly depend on irradiation dose and inlet NOx concentration. For NOx concentrations above 800 ppmv low removal efficiencies were obtained even if applied high doses. In the second part of study the irradiated gases were directed to the seawater scrubber for further purification. The scrubbing process enhances removal efficiencies of both pollutants. The SO2 removal efficiencies above 98.5% were obtained with irradiation dose greater than 5.3 kGy. For inlet NOx concentrations of 1700 ppmv the NOx removal efficiency about 51% was obtained with dose greater than 8.8 kGy. Methods for further increase of NOx removal efficiency are presented in the paper.

  16. Warming Early Mars by Impact Degassing of Reduced Greenhouse Gases

    Haberle, R. M.; Zahnle, K.; Barlow, N. G.

    2018-01-01

    Reducing greenhouse gases are once again the latest trend in finding solutions to the early Mars climate dilemma. In its current form collision induced absorptions (CIA) involving H2 and/or CH4 provide enough extra greenhouse power in a predominately CO2 atmosphere to raise global mean surface temperatures to the melting point of water provided the atmosphere is thick enough and the reduced gases are abundant enough. Surface pressures must be at least 500 mb and H2 and/or CH4 concentrations must be at or above the several percent level for CIA to be effective. Atmospheres with 1-2 bars of CO2 and 2- 10% H2 can sustain surface environments favorable for liquid water. Smaller concentrations of H2 are sufficient if CH4 is also present. If thick CO2 atmospheres with percent level concentrations of reduced gases are the solution to the faint young Sun paradox for Mars, then plausible mechanisms must be found to generate and sustain the gases. Possible sources of reducing gases include volcanic outgassing, serpentinization, and impact delivery; sinks include photolyis, oxidation, and escape to space. The viability of the reduced greenhouse hypothesis depends, therefore, on the strength of these sources and sinks. In this paper we focus on impact delivered reduced gases.

  17. μ+ charge exchange and muonium formation in low pressure gases

    Fleming, D.G.; Mikula, R.J.; Garner, D.M.

    1982-04-01

    Using the basic muon spin rotation technique, the fractions of energetic positive muons thermalizing in diamagnetic environments (fsub(μ)) or as the paramagnetic muonium atom (fsub(Mu)) have been measured in low pressure pure gases (He, Ne, Ar, Kr, Xe, H 2 , N 2 , NH 3 , and CH 4 ) as well as in several gas mixtures (Ne/Xe, Ne/Ar, Ne/NH 3 , Ne/CH 4 ). In the pure gases, the muonium fractions fsub(Mu) are generally found to be smaller than expected from analogous proton charge exchange studies, particularly in the molecular gases. This is probably due to hot atom reactions of muonium following the charge exchange regime. Comparisons with monium formation in condensed matter as well as positronium formation in gases are also presented. In the gas mixtures, the addition of only a few hundred ppm of a dopant gas, which is exothermic for muonium formation (e.g. Xe), gives rise to an fsub(Mu) characteristic of the pure dopant gas itself, demonstrating the importance of the neutralization process right down to thermal energies. In all cases, the experimental signal amplitudes are found to be strongly pressure dependent, which is interpreted in terms of the time spent by the muon as neutral muonium in the charge exchange regime: tsub(n) < 0.2 ns. This time is generally shorter in the case of molecular gases than in rare gases

  18. Use of gases in dairy manufacturing: A review.

    Adhikari, Bhaskar Mani; Truong, Tuyen; Bansal, Nidhi; Bhandari, Bhesh

    2017-06-13

    Use of gases (air, carbon dioxide and nitrogen) has been practiced in the manufacture of dairy products (i.e., ice cream, whipped cream and butter) to improve their texture, mouthfeel and shelf-life extension. Many attempts have also been made to incorporate other gases such as hydrogen, nitrous oxide, argon, xenon, and helium into the dairy systems for various product functionalities such as whipping, foaming, texture, aroma enhancement, and therapeutic properties. The gases can be dissolved in aqueous and fat phases or remain in the form of bubbles stabilized by protein or fat particles. The gas addition or infusion processes are typically simple and have been used commercially. This review focuses on the use of various gases in relation to their individually physical properties along with their specific roles in manufacturing and controlling quality of dairy products. It also recaps on how gases are included in the dairy systems. The information is important in understanding of addition of specific gas(es) into food systems, particularly dairy products, that potentially provide intervention opportunities for modifying and/or creating innovative food structures and functionalities.

  19. Electron thermalization in rare gases and their mixtures

    Bronic, I.K.; Kimura, M.

    1996-01-01

    The time evolution and temperature dependence of electron energy distribution functions (EDFs) are studied in pure rare gases (He, Ne, Ar, Kr, Xe) as well as in their mixtures by using solutions of the Boltzmann equation. A clear difference between the gases having the Ramsauer endash Townsend (RT) minimum in the momentum-transfer cross section, (RT gases: Ar, Kr, and Xe), and those without the RT minimum (non-RT gases: He and Ne) is pointed out. The influence of the position and the depth of the RT minimum on the EDF and time evolution is studied for three different initial electron energies. A formula proposed for describing thermalization time in a mixture is tested on (i) a non-RT endash non-RT gas mixture, (ii) a RT endash non-RT mixture and (iii) a RT endash RT gas mixture. The linear combination of the reciprocal thermalization times in gas mixture with the component concentrations as weighting factors is found to be valid for gases with a similar energy dependence of the momentum-transfer cross section, σ m , and also for all rare-gas binary mixtures if the initial electron energy is sufficiently below the RT minimum. Conspicuous deviations from the linear relationship are observed in mixtures of gases whose energy dependence of σ m (or the stopping cross section) are different, and theoretical rationales for these findings are provided. copyright 1996 American Institute of Physics

  20. Oral cavity and jaw

    Solntsev, A.M.; Koval', G.Yu.

    1984-01-01

    Radioanatome of oral cavity and jaw is described. Diseases of the teeth, jaw, large salivary glands, temporo-mandibular articulation are considered. Roentgenograms of oral cacity and jaw of healthy people are presented and analyzed as well as roentgenograms in the above-mentioned diseases

  1. Oral Microbiology and Immunology

    Dahlén, Gunnar; Fiehn, Nils-Erik; Olsen, Ingar

    , dental assistants and trainees may find it a useful source of reference. The contents are based on general microbiology and immunology. Oral microbiology is given particular attention, with examples relevant to oral infectious diseases. Each chapter opens with a relatively short pre-reading section...

  2. Brachytherapy for oral cancer

    Monzen, Yoshio; Ajimu, Akira; Morikawa, Minoru; Hayashi, Nobuyuki; Yoshida, Shintarou; Ashizawa, Kazuto; Hayashi, Kuniaki; Ikenaga, Kouji; Sakamoto, Ichirou.

    1988-01-01

    13 cases with oral cancer were treated using brachytherapy at the Department of Radiology, Nagasaki University Hospital from September 1985 to February 1988. Among 11 cases of tongue cancer, T1 and T2 cases were well controlled by radiation therapy using 226 Ra needles. Cancer of oral floor and buccal mucosa were controlled by the use of 192 Au grains. (author)

  3. Head, Neck, and Oral Cancer

    Full Text Available ... Oral Surgeries Facial Cosmetic Surgery Facial Injury / Trauma Surgery Obstructive Sleep Apnea (OSA) Oral, Head and Neck Pathology TMJ and Facial Pain Wisdom Teeth Management Procedures Anesthesia Anesthesia Oral and maxillofacial surgeons are ...

  4. American Academy of Oral Medicine

    ... Statements Newsletters AAOM: Representing the Discipline of Oral Medicine Oral Medicine is the discipline of dentistry concerned with the ... offers credentialing, resources and professional community for oral medicine practitioners. Our membership provides care to thousands. We ...

  5. What Is an Oral Piercing?

    ... to your desktop! more... What Is an Oral Piercing? Article Chapters What Is an Oral Piercing? print full article print this chapter email this article Oral piercing can cause pain, swelling, infection, drooling, taste loss, ...

  6. Literatura Oral Hispanica (Hispanic Oral Literature).

    McAlpine, Dave

    As part of a class in Hispanic Oral Literature, students collected pieces of folklore from various Hispanic residents in the region known as "Siouxland" in Iowa. Consisting of some of the folklore recorded from the residents, this paper includes 18 "cuentos y leyendas" (tales and legends), 48 "refranes" (proverbs), 17…

  7. Safety characteristics. Vol. 1. Combustible liquids and gases; Sicherheitstechnische Kenngroessen. Bd. 1. Brennbare Fluessigkeiten und Gase

    Brandes, E.; Moeller, W. [Laboratorium ' Sicherheitstechnische Kenngroessen' , Braunschweig (Germany)

    2003-07-01

    This reference manual is based on the 2002 version of the CHEMSAFE database, which is produced since 1989 by the PTB (Physikalisch-Technische Bundesanstalt), the BAM (Bundesanstalt fuer Materialforschung und -pruefung) and the DECHEMA (Gesellschaft fuer Chemische Technik und Biotechnologie e.V.). About 1,900 combustible gases and vapours are listed, along with explosion protection characteristics like flame point, ignition temperature, explosion limits, minimum ignition energy, normal gap width, maximum explosion pressure, and maximum pressure increase over time. Important thermophysical data are presented as well, e.g. boiling temperature, vapour pressure as a function of temperature, melting temperature, and density. Definitions of the characteristics are presented. There are several indexis to facilitate acces (CAS number, sum formula, synonyms). [German] Anwender in Industrie, Handel, Handwerk und Behoerden benoetigen verlaessliche Daten, von Fachleuten bewertete Kenngroessen des Brand- und Explosionsschutzes, um Brand- und Explosionsgefahren beim Verarbeiten, Abfuellen, Lagern, Befoerdern und Entsorgen brennbarer Stoffe beurteilen und angemessene Schutzmassnahmen ergreifen zu koennen. Die 1989 gemeinsam mit der Bundesanstalt fuer Materialfoschung und -pruefung (BAM) und der Gesellschaft fuer Chemische Technik und Biotechnologie e.v (DECHEMA) erstellte Datenbank CHEMSAFE diente als Grundlage dieses Nachschlagewerkes. Die hier bei Drucklegung wiedergegebenen Kenngroessen entsprechen dem Update 2002 der Datenbank CHEMSAFE. Etwa 1.900 brennbare Gase und Daempfe, Kenngroessen des Explosionsschutzes wie Flammpunkt, Zuendtemperatur, Explosionsgrenzen, Mindestzuendenergie, Normspaltweite, maximaler Explosionsdruck und maximaler zeitlicher Druckanstieg sind ebenso aufgelistet wie auch einige wichtige thermophysikalische Groessen wie Siedetemperatur, Dampfdruck als Funktion der Temperatur, Schmelztemperatur und Dichte. Die Angaben werden eingeleitet durch Definitionen

  8. Process for the removal of acid forming gases from exhaust gases and production of phosphoric acid

    Chang, Shih-Ger; Liu, David K.

    1992-01-01

    Exhaust gases are treated to remove NO or NO.sub.x and SO.sub.2 by contacting the gases with an aqueous emulsion or suspension of yellow phosphorous preferably in a wet scrubber. The addition of yellow phosphorous in the system induces the production of O.sub.3 which subsequently oxidizes NO to NO.sub.2. The resulting NO.sub.2 dissolves readily and can be reduced to form ammonium ions by dissolved SO.sub.2 under appropriate conditions. In a 20 acfm system, yellow phosphorous is oxidized to yield P.sub.2 O.sub.5 which picks up water to form H.sub.3 PO.sub.4 mists and can be collected as a valuable product. The pressure is not critical, and ambient pressures are used. Hot water temperatures are best, but economics suggest about 50.degree. C. The amount of yellow phosphorus used will vary with the composition of the exhaust gas, less than 3% for small concentrations of NO, and 10% or higher for concentrations above say 1000 ppm. Similarly, the pH will vary with the composition being treated, and it is adjusted with a suitable alkali. For mixtures of NO.sub.x and SO.sub.2, alkalis that are used for flue gas desulfurization are preferred. With this process, better than 90% of SO.sub.2 and NO in simulated flue gas can be removed. Stoichiometric ratios (P/NO) ranging between 0.6 and 1.5 were obtained.

  9. Biological processes for mitigation of greenhouse gases

    Benemann, John R. [California Univ., Dept. of Plant and Microbial Biology, Berkeley, CA (United States)

    1999-07-01

    Biological processes driven by photosynthesis cycle through the atmosphere well over an order of magnitude more CO{sub 2} than is currently emitted from the combustion of fossils fuels. Already human activities control and appropriate almost half the primary photosynthetic productivity of the planet. Better management of natural and man-made ecosystems affords many opportunities for mitigation of greenhouse gases, through sink enhancements, source reduction and substitution of fossil fuels with biofuels. Biofuels can be recovered from most organic wastes, from agricultural and forestry residues, and from biomass produced solely for energy use. However, the currently low costs of fossil fuels limits the market for biofuels. Accounting for the greenhouse mitigation value of biofuels would significantly increase their contribution to world fuel suppliers, estimated to be currently equivalent to about 15% of fossil fuel usage. Another limiting factor in expanding the use of biofuels is the relatively low solar energy conversion efficiencies of photosynthesis. Currently well below 1% of solar energy is converted into biomass energy even by intensive agricultural or forestry systems, with peak conversion efficiencies about 2 to 3% for sugar cane or microalgae cultures. One approach to increase photosynthetic efficiencies, being developed at the University of California Berkeley, is to reduce the amount of light-gathering chlorophyll in microalgae and higher plants. This would reduce mutual shading and also increase photosynthetic efficiencies under full sunlight intensities. Estimates of the potential of photosynthetic greenhouse mitigation processes vary widely. However, even conservative estimates for biofuels substituting for fossil fuels project the potential to reduce a large fraction of current increases in atmospheric CO{sub 2} levels. Biofuels production will require integration with existing agronomic, forestry and animal husbandry systems, and improved

  10. TEACHING MULTIPLICATION OF NUMBERS FROM 1 TO 10 TO STKIP SURYA STUDENTS USING MATEMATIKA GASING

    Josephine Kusuma

    2014-01-01

    Full Text Available Multiplication of numbers from 1 to 10 is very important as it provides the basis for learning multiplication of other larger numbers as well as other related mathematical operations. How do students learn multiplication? Usually students just memorize the results of multiplication. This is often performed without a complete comprehension of the concept of multiplication. This study aimed to discuss how to teach multiplication of numbers from 1 to 10 to STKIP Surya students using Matematika GASING. GASING stands for Gampang, ASyIk dan menyenaNGkan which is translated as easy, fun and enjoyable. The materials are taught according to its unique way of teaching mathematics which follows three stages: concrete, abstract and mental calculation. The first stage (concrete encourages students to explore using concrete objects. This is done prior to the second stage called the abstract stage. Students are then able to move on to the third stage where they can do mathematical calculation mentally and instantly. By following these stages in this order, students can understand mathematics more easily and clearly. The research method used in this study was design research. It consists of three phases; they are preliminary design, teaching experiment and retrospective analysis.The sample was fourteen first-year undergraduate students (matriculation level at STKIP Surya (Surya College of Education, Tangerang, Banten. The instruments used were both oral and written tests. They were used to measure the ability of performing mental computation as well as the ability to teach this material. This study showed that Matematika GASING helpedthese students to understand and be able to teach multiplication of numbers from 1 to 10 better.Keywords: multiplication of numbers from 1 to 10, Matematika GASING, design research DOI: http://dx.doi.org/10.22342/jme.5.1.1450.66-84

  11. Head, Neck, and Oral Cancer

    Full Text Available ... Oral and maxillofacial surgeons surgically treat the soft tissues of the face, mouth ... involving skin, muscle, bone and cartilage finely attune the oral and maxillofacial ...

  12. Examining the association between oral health and oral HPV infection.

    Bui, Thanh Cong; Markham, Christine M; Ross, Michael Wallis; Mullen, Patricia Dolan

    2013-09-01

    Oral human papillomavirus (HPV) infection is the cause of 40% to 80% of oropharyngeal cancers; yet, no published study has examined the role of oral health in oral HPV infection, either independently or in conjunction with other risk factors. This study examined the relation between oral health and oral HPV infection and the interactive effects of oral health, smoking, and oral sex on oral HPV infection. Our analyses comprised 3,439 participants ages 30 to 69 years for whom data on oral HPV and oral health were available from the nationally representative 2009-2010 National Health and Nutrition Examination Survey. Results showed that higher unadjusted prevalence of oral HPV infection was associated with four measures of oral health, including self-rated oral health as poor-to-fair [prevalence ratio (PR) = 1.56; 95% confidence interval (CI), 1.25-1.95], indicated the possibility of gum disease (PR = 1.51; 95% CI, 1.13-2.01), reported use of mouthwash to treat dental problems in the past week (PR = 1.28; 95% CI, 1.07-1.52), and higher number of teeth lost (Ptrend = 0.035). In multivariable logistic regression models, oral HPV infection had a statistically significant association with self-rated overall oral health (OR = 1.55; 95% CI, 1.15-2.09), independent of smoking and oral sex. In conclusion, poor oral health was an independent risk factor of oral HPV infection, irrespective of smoking and oral sex practices. Public health interventions may aim to promote oral hygiene and oral health as an additional measure to prevent HPV-related oral cancers.

  13. Effects of elemental sulfur and sulfur-containing waste on nutrient ...

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... grown twice on the same soils to determine initial and residual effects of applied S. Results showed that applications of ... Key words: Calcareous soil, plant growth, plant nutrition, sulfur application. ...... Colombia. Can. J. Soil ...

  14. [Oxidation of sulfur-containing substrates by aboriginal and experimentally designed microbial communities].

    Pivovarova, T A; Bulaev, A G; Roshchupko, P V; Belyĭ, A V; Kondrat'eva, T F

    2012-01-01

    Aboriginal and experimental (constructed of pure microbial cultures) communities of acidophilic chemolithotrophs have been studied. The oxidation of elemental sulfur, sodium thiosulfate, and potassium tetrathionate as sole sources of energy has been monitored. The oxidation rate of the experimental community is higher as compared to the aboriginal community isolated from a flotation concentrate of pyrrhotine-containing pyrite-arsenopyrite gold-arsenic sulfide ore. The degree of oxidation of the mentioned S substrates amounts to 17.91, 68.30, and 93.94% for the experimental microbial community and to 10.71, 56.03, and 79.50% for the aboriginal community, respectively. The degree of oxidation of sulfur sulfide forms in the ore flotation concentrate is 59.15% by the aboriginal microbial community and 49.40% by the experimental microbial community. Despite a higher rate of oxidation of S substrates as a sole source of energy by the experimental microbial community, the aboriginal community oxidizes S substrates at a higher rate in the flotation concentrate of pyrrhotine-containing pyrite-arsenopyrite gold-arsenic sulfide ore, from which it was isolated. Bacterial-chemical oxidation of the flotation concentrate by the aboriginal microbial community allows for the extraction of an additional 32.3% of gold from sulfide minerals, which is by 5.7% larger compared to the yield obtained by the experimental microbial community.

  15. Mechanical and Electrical Properties of Sulfur-Containing Polymeric Materials Prepared via Inverse Vulcanization

    Sergej Diez

    2017-02-01

    Full Text Available Recently, new methods have been developed for the utilization of elemental sulfur as a feedstock for novel polymeric materials. One promising method is the inverse vulcanization, which is used to prepare polymeric structures derived from sulfur and divinyl comonomers. However, the mechanical and electrical properties of the products are virtually unexplored. Hence, in the present study, we synthesized a 200 g scale of amorphous, hydrophobic as well as translucent, hyperbranched polymeric sulfur networks that provide a high thermal resistance (>220 °C. The polymeric material properties of these sulfur copolymers can be controlled significantly by varying the monomers as well as the feed content. The investigated comonomers are divinylbenzene (DVB and 1,3-diisopropenylbenzene (DIB. Plastomers with low elastic content and high shape retention containing 12.5%–30% DVB as well as low viscose waxy plastomers with a high flow behavior containing a high DVB content of 30%–35% were obtained. Copolymers with 15%–30% DIB act, on the one hand, as thermoplastics and, on the other hand, as vitreous thermosets with a DIB of 30%–35%. Results of the thermogravimetric analysis (TGA, the dynamic scanning calorimetry (DSC and mechanical characterization, such as stress–strain experiments and dynamic mechanical thermal analysis, are discussed with the outcome that they support the assumption of a polymeric cross-linked network structure in the form of hyper-branched polymers.

  16. Influence of ionizing radiation on DNA in presence of sulfur-containing radioprotectors. 1

    Mallet, G.; Rix-Montel, M.A.; Vasilescu, D.

    1982-01-01

    A spectrophotometric investigation on DNA solutions γ-irradiated in a dose range up to 100 Gy is reported. Examination of the geometric properties of DNA melting curves in the low dose range (0-20 Gy) reveals a particular dose effect: the melting point of DNA is superior to that of non-irradiated DNA, but there is invariance of the thermal denaturation percentage. It is supposed that the observed effect is essentially due to conformational changes of the DNA backbone and not to single or double strand breaks. In the irradiation range explored, the melting curves slope was decreasing continuously. For doses beyond 20 Gy the habitual destruction of the secondary structure of DNA was observed

  17. Metal-molecular interface of sulfur-containing amino acid and thiophene on gold surface

    Honda, M; Baba, Y; Hirao, N; Sekiguchi, T

    2008-01-01

    Chemical-bonding states of metal-molecular interface have been investigated for L-cysteine and thiophene on gold by x-ray photoelectron spectroscopy (XPS) and near edge x-ray adsorption fine structure (NEXAFS). A remarkable difference in Au-S bonding states was found between L-cysteine and thiophene. For mono-layered L-cysteine on gold, the binding energy of S 1s in XPS and the resonance energy at the S K-edge in NEXAFS are higher by 8-9 eV than those for multi-layered film (molecular L-cysteine). In contrast, the S K-edge resonance energy for mono-layered thiophene on gold was 2475.0 eV, which is the same as that for molecular L-cysteine. In S 1s XPS for mono-layered thiophene, two peaks were observed. The higher binging-energy and more intense peak at 2473.4 eV are identified as gold sulfide. The binding energy of smaller peak, whose intensity is less than 1/3 of the higher binding energy peak, is 2472.2 eV, which is the same as that for molecular thiophene. These observations indicate that Au-S interface behavior shows characteristic chemical bond only for the Au-S interface of L-cysteine monolayer on gold substrate

  18. Process and system for removing sulfur from sulfur-containing gaseous streams

    Basu, Arunabha; Meyer, Howard S.; Lynn, Scott; Leppin, Dennis; Wangerow, James R.

    2012-08-14

    A multi-stage UCSRP process and system for removal of sulfur from a gaseous stream in which the gaseous stream, which contains a first amount of H.sub.2S, is provided to a first stage UCSRP reactor vessel operating in an excess SO.sub.2 mode at a first amount of SO.sub.2, producing an effluent gas having a reduced amount of SO.sub.2, and in which the effluent gas is provided to a second stage UCSRP reactor vessel operating in an excess H.sub.2S mode, producing a product gas having an amount of H.sub.2S less than said first amount of H.sub.2S.

  19. Synthesis and characterization of porous metal oxides and desulfurization studies of sulfur containing compounds

    Garces Trujillo, Hector Fabian

    This thesis contains two parts: 1) synthesis and characterization of porous metal oxides that include zinc oxide and a porous mixed-valent manganese oxide with an amorphous structure (AMO) 2) the desulfurization studies for the removal of sulfur compounds. Zinc oxide with different nano-scale morphologies may result in various porosities with different adsorption capabilities. A tunable shape microwave synthesis of ZnO nano-spheres in a co-solvent mixture is presented. The ZnO nano-sphere material is investigated as a desulfurizing sorbent in a fixed bed reactor in the temperature range 200 to 400 °C and compared with ZnO nanorods and platelet-like morphologies. Fresh and sulfided materials were characterized by X-ray diffraction (XRD), BET specific surface area, pore volume, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (SEM/EDX), Raman spectroscopy, and thermogravimetric analysis (TGA). The tunable shape microwave synthesis of ZnO presents a high sulfur sorption capacity at temperatures as low as 200 °C which accounts for a three and four fold enhancement over the other preparations presented in this work, and reached 76 % of the theoretical sulfur capacity (TSC) at 300 °C. Another ZnO material with a bimodal micro- and mesopore size distribution investigated as a desulfurizing sorbent presents a sorption capacity that reaches 87% of the theoretical value for desulfurization at 400 °C at breakthrough time. A deactivation model that considers the activity of the solid reactant was used to fit the experimental data. Good agreement between the experimental breakthrough curves and the model predictions are obtained. Manganese oxides are a type of metal oxide materials commonly used in catalytic applications. Little is known about the adsorption capabilities for the removal of sulfur compounds. One of these manganese oxides; amorphous manganese oxide (AMO) is highly promising material for low temperature sorption processes. Amorphous manganese oxide (AMO) has been used in catalytic processes such as for the catalytic oxidation of benzyl alcohol, the preferential oxidation of CO, and for the capture of formate species. This chapter explores the possibility of using AMO in sorption processes for the removal of two contaminants; H 2S and COS in the temperature range 200 - 400 °C.

  20. Kinetics of reaction of peroxynitrite with selenium- and sulfur-containing compounds

    Storkey, Corin; Pattison, David I.; Ignasiak, Marta T.

    2015-01-01

    with peroxynitrite with high rate constants. Low molecular mass selenols react particularly rapidly with peroxynitrite, with second order rate constants k2 in the range 5.1×105-1.9×106 M-1 s-1, and 250-830 fold faster than the corresponding thiols (RSH) and many other endogenous biological targets. Reactions......Peroxynitrite (the physiological mixture of ONOOH and its anion, ONOO-) is a powerful biologically-relevant oxidant capable of oxidizing and damaging a range of important targets including sulfides, thiols, lipids, proteins, carbohydrates and nucleic acids. Excessive production of peroxynitrite...... of peroxynitrite with selenides, including selenosugars are approximately 15-fold faster than their sulfur homologs with k2 approximately 2.5×103 M-1 s-1. The rate constants for diselenides and sulfides were slower with k2 0.72-1.3×103 M-1 s-1 and approximately 2.1×102 M-1 s-1 respectively. These studies...

  1. Responses of plants to sulfur containing air pollutants (H2S and SO2)

    Maas, Franciscus Marie

    1987-01-01

    Effects of air pollution by hydrogen sulfide (H2S) and sulfur dioxide (SO2) were already reported more than half a century ago. The wider range of pollution by SO2 is reflected in the number of publications concerning effects of SO2 on plants. The major part of the reported studies effects of SO2

  2. A method for nitric oxide radical scavenging properties of sulfur containing compounds.

    Vriesman, M.F.; Haenen, G.R.M.M.; Westerveld, G.J.; Paquay, J.B.G.; Voss, H.P.; Bast, A.

    1997-01-01

    A new method for the quantification of the nitric oxide (NO) scavenging activity of compounds in aqueous solutions is described using an amperometric NO sensor. After correction for the spontaneous degradation of NO, second-order rate kinetics of the scavenging reaction are observed.

  3. Stress Corrosion Cracking of Ni-base Alloys in Sulfur Containing Solutions at 340 .deg. C

    Lee, Eun Hee; Hwang, Seong Sik; Kim, Dong Jin; Kim, Sung Woo [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Sulfur has been identified as one of the major impurities introduced into the secondary water of pressurized water-reactors (PWRs). Sulfur can originate from various sources, such as resin sources, feed water, cooling water in-leakage, and condenser leaks. Many authors have investigated effects of reduced sulfur in a wide pH range with or without additives. The presence of reduced sulfur species on the surfaces of pulled tubes having stress corrosion cracking (SCC) was also identified. In present work, SCC tests were conducted to investigate effects of reduced sulfur species on the SCC behavior of Ni-base Alloys. The Alloy 690 TT showed the most SCC resistant, regardless of the sulfur species. The Cr content and heat treatments of alloys appeared the increase in the SCC resistance.

  4. Antibacterial and antifungal activity of sulfur-containing compounds from Petiveria alliacea L.

    Kim, Seokwon; Kubec, Roman; Musah, Rabi A

    2006-03-08

    A total of 18 organosulfur compounds originating from Petiveria alliacea L. roots have been tested for their antibacterial and antifungal activities. These represent compounds occurring in fresh homogenates as well as those present in various macerates, extracts and other preparations made from Petiveria alliacea. Of the compounds assayed, the thiosulfinates, trisulfides and benzylsulfinic acid were observed to be the most active, with the benzyl-containing thiosulfinates exhibiting the broadest spectrum of antimicrobial activity. The effect of plant sample preparation conditions on the antimicrobial activity of the extract is discussed.

  5. Pentacyclic triterpenoids with nitrogen- and sulfur-containing heterocycles: synthesis and medicinal significance

    Kvasnica, Miroslav; Urban, M.; Dickinson, N.J.; Sarek, J.

    2015-01-01

    Roč. 32, č. 9 (2015), s. 1303-1330 ISSN 0265-0568 R&D Projects: GA ČR(CZ) GJ15-08202Y; GA MŠk(CZ) LO1304; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : BETULINIC ACID-DERIVATIVES * C-LACTAM DERIVATIVES * OLEANOLIC ACID Subject RIV: CC - Organic Chemistry Impact factor: 10.986, year: 2015

  6. Effect of iron and chromium on the graphitization behaviour of sulfur-containing carbon

    Tyumentsev, V.A.; Belenkov, E.A.; Saunina, S.I.; Podkopaev, S.A.; Shvejkin, G.P.

    1998-01-01

    Process of transition of carbonaceous material, containing structurally incorporated sulfur, into graphite and impact of iron and chromium additions are studied. It is established that carbonaceous material, containing more than 1.5 mass % S and also 1.5 mass % Cr 2 O 3 is heterogeneous after thermal treatment at 1300-1600 deg C. It consists of large and sufficiency complete areas of coherent scattering having graphite structure and ultra-dispersed matrix. The number of graphite crystals formed in the presence of dispersed iron within this temperature range, decreases by two times [ru

  7. Transition processes in solid-phase electrochemical systems including sulfur-containing components

    Arkhipova, N.V.; Mikhajlova, A.M.; Seryanov, Yu.V.

    2005-01-01

    Transition processes in direct-contact systems Li/Sb 2 S 3 and Li/Sb 2 S 5 are studied. As shown by potentiodynamic voltammetry, an Li 3 SbS 3 interphase is the most probable product of the cathodic reduction at direct-contact interfaces. At certain polarizations and current densities, under potentiodynamic and galvanostatic conditions, the main current-producing processes that lead to the formation of the Li 3 SbS 3 interphase compete with passivating cathodic reactions which occur via the mechanism of monolayer adsorption and result in the formation of an Li 2 S product which blocks grains of the lithium thiostibnite interphase. Effective transfer coefficients of passivating reactions are twice those of the main current-producing cathodic reactions [ru

  8. Prevention of gingival trauma : Oral hygiene devices and oral piercings

    Hoenderdos, N.L.

    2017-01-01

    Maintaining healthy teeth and soft oral tissues for life is important. Oral hygiene devices and oral piercings can damage the soft oral tissues. This thesis investigates the safety of manual toothbrushes, interdental brushes and rubber bristles interdental cleaners by analysing the gingival abrasion

  9. Noble gases recycled into the mantle through cold subduction zones

    Smye, Andrew J.; Jackson, Colin R. M.; Konrad-Schmolke, Matthias; Hesse, Marc A.; Parman, Steve W.; Shuster, David L.; Ballentine, Chris J.

    2017-08-01

    Subduction of hydrous and carbonated oceanic lithosphere replenishes the mantle volatile inventory. Substantial uncertainties exist on the magnitudes of the recycled volatile fluxes and it is unclear whether Earth surface reservoirs are undergoing net-loss or net-gain of H2O and CO2. Here, we use noble gases as tracers for deep volatile cycling. Specifically, we construct and apply a kinetic model to estimate the effect of subduction zone metamorphism on the elemental composition of noble gases in amphibole - a common constituent of altered oceanic crust. We show that progressive dehydration of the slab leads to the extraction of noble gases, linking noble gas recycling to H2O. Noble gases are strongly fractionated within hot subduction zones, whereas minimal fractionation occurs along colder subduction geotherms. In the context of our modelling, this implies that the mantle heavy noble gas inventory is dominated by the injection of noble gases through cold subduction zones. For cold subduction zones, we estimate a present-day bulk recycling efficiency, past the depth of amphibole breakdown, of 5-35% and 60-80% for 36Ar and H2O bound within oceanic crust, respectively. Given that hotter subduction dominates over geologic history, this result highlights the importance of cooler subduction zones in regassing the mantle and in affecting the modern volatile budget of Earth's interior.

  10. Interaction of Se and GaSe with Si(111)

    Meng, Shuang; Schroeder, B. R.; Olmstead, Marjorie A.

    2000-01-01

    Deposition of Se and GaSe on Si(111)7x7 surfaces was studied with low-energy electron diffraction, x-ray photoelectron spectroscopy, and x-ray photoelectron diffraction to probe initial nucleation and interface structure for GaSe/Si(111) heteroepitaxy. Room-temperature deposition of Se on Si(111)7x7 results in an amorphous film. Subsequent annealing leads to Se evaporation without ordering or interdiffusion. Se deposition at 450 degree sign C saturates at submonolayer coverage with no diffusion of Se into the substrate. There is no clear evidence of ordered sites for the Se. Growth of GaSe on Si(111)7x7 above 500 degree sign C results in a pseudomorphic bilayer, with Si-Ga-Se bonding. Additional GaSe does not stick to the bilayer above 525 degree sign C. The resulting Se lone pair at the surface leads to an ideally passivated surface similar to As/Si(111). This stable surface is similar to the layer termination in bulk GaSe. The single domain bilayer is oriented with the Ga-Se bond parallel to the substrate Si-Si bond. (c) 2000 The American Physical Society

  11. [Prospects for Application of Gases and Gas Hydrates to Cryopreservation].

    Shishova, N V; Fesenko, E E

    2015-01-01

    In the present review, we tried to evaluate the known properties of gas hydrates and gases participating in the formation of gas hydrates from the point of view of the mechanisms of cryoinjury and cryoprotection, to consider the papers on freezing biological materials in the presence of inert gases, and to analyze the perspectives for the development of this direction. For the purpose, we searched for the information on the physical properties of gases and gas hydrates, compared processes occured during the formation of gas hydrates and water ice, analyzed the influence of the formation and growth of gas hydrates on the structure of biological objects. We prepared a short review on the biological effects of xenon, krypton, argon, carbon dioxide, hydrogen sulfide, and carbon monoxide especially on hypothermal conditions and probable application of these properties in cryopreservation technologies. The description of the existing experiments on cryopreservation of biological objects with the use of gases was analyzed. On the basis of the information we found, the most perspective directions of work in the field of cryopreservation of biological objects with the use of gases were outlined. An attempt was made to forecast the potential problems in this field.

  12. Cromolyn Oral Inhalation

    ... your doctor.Cromolyn oral inhalation helps to prevent asthma attacks (sudden episodes of shortness of breath, wheezing, and coughing) but will not stop an asthma attack that has already started. Your doctor will prescribe ...

  13. Intravenous versus oral etoposide

    Ali, Abir Salwa; Grönberg, Malin; Langer, Seppo W.

    2018-01-01

    High-grade gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs, G3) are aggressive cancers of the digestive system with poor prognosis and survival. Platinum-based chemotherapy (cisplatin/carboplatin + etoposide) is considered the first-line palliative treatment. Etoposide is frequently...... administered intravenously; however, oral etoposide may be used as an alternative. Concerns for oral etoposide include decreased bioavailability, inter- and intra-patient variability and patient compliance. We aimed to evaluate possible differences in progression-free survival (PFS) and overall survival (OS......) in patients treated with oral etoposide compared to etoposide given as infusion. Patients (n = 236) from the Nordic NEC study were divided into three groups receiving etoposide as a long infusion (24 h, n = 170), short infusion (≤ 5 h, n = 33) or oral etoposide (n = 33) according to hospital tradition. PFS...

  14. Fostering oral presentation performance

    Ginkel, van Stan; Gulikers, Judith; Biemans, Harm; Mulder, Martin

    2017-01-01

    Previous research revealed significant differences in the effectiveness of various feedback sources for encouraging students’ oral presentation performance. While former studies emphasised the superiority of teacher feedback, it remains unclear whether the quality of feedback actually differs

  15. Oral Cancer Foundation

    ... Get involved Understanding Dental Research People Resources About Understanding Events Get involved Dental Research Resources Contact Sitemap The Oral Cancer Foundation admin 2017-11-12T16:49:25+ ...

  16. Maintaining women's oral health.

    McCann, A L; Bonci, L

    2001-07-01

    Women must adopt health-promoting strategies for both general health and the oral cavity, because the health of a woman's body and oral cavity are bidirectional. For general health-maintenance strategies, dental practitioners should actively advise women to minimize alcohol use, abstain from or cease smoking, stay physically active, and choose the right foods to nourish both the body and mind. For oral health-maintenance strategies, dental practitioners should advise women on how to prevent or control oral infections, particularly dental caries and periodontal diseases. Specifically, women need to know how to remove plaque from the teeth mechanically, use appropriate chemotherapeutic agents and dentifrices, use oral irrigation, and control halitosis. Dental practitioners also need to stress the importance of regular maintenance visits for disease prevention. Adolescent women are more prone to gingivitis and aphthous ulcers when they begin their menstrual cycles and need advice about cessation of tobacco use, mouth protection during athletic activities, cleaning orthodontic appliances, developing good dietary habits, and avoiding eating disorders. Women in early to middle adulthood may be pregnant or using oral contraceptives with concomitant changes in oral tissues. Dental practitioners need to advise them how to take care of the oral cavity during these changes and how to promote the health of their infants, including good nutrition. Older women experience the onset of menopause and increased vulnerability to osteoporosis. They may also experience xerostomia and burning mouth syndrome. Dental practitioners need to help women alleviate these symptoms and encourage them to continue good infection control and diet practices.

  17. ON ORAL CANCER

    P. V. Svetitsky

    2012-01-01

    Full Text Available The paper analyzes a rise in the incidence of oral cancer in the Rostov Region since the 1990s. The study has indicated that this rise is associated with regional population growth due to the forced migrants after the collapse of the USSR. Financial problems, unbalanced nutrition, poor oral hygiene, and depression in this group of patients have contributed to the higher incidence of precancers and cancers.

  18. Oral vs. salivary diagnostics

    Marques, Joana; Corby, Patricia M.; Barber, Cheryl A.; Abrams, William R.; Malamud, Daniel

    2015-05-01

    The field of "salivary diagnostics" includes studies utilizing samples obtained from a variety of sources within the oral cavity. These samples include; whole unstimulated saliva, stimulated whole saliva, duct saliva collected directly from the parotid, submandibular/sublingual glands or minor salivary glands, swabs of the buccal mucosa, tongue or tonsils, and gingival crevicular fluid. Many publications state "we collected saliva from subjects" without fully describing the process or source of the oral fluid. Factors that need to be documented in any study include the time of day of the collection, the method used to stimulate and collect the fluid, and how much fluid is being collected and for how long. The handling of the oral fluid during and post-collection is also critical and may include addition of protease or nuclease inhibitors, centrifugation, and cold or frozen storage prior to assay. In an effort to create a standard protocol for determining a biomarker's origin we carried out a pilot study collecting oral fluid from 5 different sites in the mouth and monitoring the concentrations of pro- and anti-inflammatory cytokines detected using MesoScaleDiscovery (MSD) electrochemiluminesence assays. Our data suggested that 3 of the cytokines are primarily derived from the submandibular gland, while 7 of the cytokines come from a source other than the major salivary glands such as the minor salivary glands or cells in the oral mucosae. Here we review the literature on monitoring biomarkers in oral samples and stress the need for determining the blood/saliva ratio when a quantitative determination is needed and suggest that the term oral diagnostic be used if the source of an analyte in the oral cavity is unknown.

  19. Immunologically mediated oral diseases

    Jimson, Sudha; Balachader, N.; Anita, N.; Babu, R.

    2015-01-01

    Immune mediated diseases of oral cavity are uncommon. The lesions may be self-limiting and undergo remission spontaneously. Among the immune mediated oral lesions the most important are lichen planus, pemphigus, erythema multiformi, epidermolysis bullosa, systemic lupus erythematosis. Cellular and humoral mediated immunity play a major role directed against epithelial and connective tissue in chronic and recurrent patterns. Confirmatory diagnosis can be made by biopsy, direct and indirect imm...

  20. Determinants of Oral Health: Does Oral Health Literacy Matter?

    Naghibi Sistani, Mohammad Mehdi; Yazdani, Reza; Virtanen, Jorma; Pakdaman, Afsaneh; Murtomaa, Heikki

    2013-01-01

    Objective. To evaluate oral health literacy, independent of other oral health determinants, as a risk indicator for self-reported oral health. Methods. A cross-sectional population-based survey conducted in Tehran, Iran. Multiple logistic regression analysis served to estimate the predictive effect of oral health literacy on self-reported oral health status (good versus poor) controlling for socioeconomic and demographic factors and tooth-brushing behavior. Results. In all, among 1031 partici...

  1. Oral Carcinogenesis and Oral Cancer Chemoprevention: A Review

    Tanaka, Takuji; Tanaka, Mayu; Tanaka, Takahiro

    2011-01-01

    Oral cancer is one of the major global threats to public health. The development of oral cancer is a tobacco-related multistep and multifocal process involving field cancerization and carcinogenesis. The rationale for molecular-targeted prevention of oral cancer is promising. Biomarkers of genomic instability, including aneuploidy and allelic imbalance, are possible to measure the cancer risk of oral premalignancies. Understanding of the biology of oral carcinogenesis will yield important adv...

  2. Oral microbiome and oral and gastrointestinal cancer risk

    Ahn, Jiyoung; Chen, Calvin Y.; Hayes, Richard B.

    2012-01-01

    A growing body of evidence implicates human oral bacteria in the etiology of oral and gastrointestinal cancers. Epidemiological studies consistently report increased risks of these cancers in men and women with periodontal disease or tooth loss, conditions caused by oral bacteria. More than 700 bacterial species inhabit the oral cavity, including at least 11 bacterial phyla and 70 genera. Oral bacteria may activate alcohol and smoking-related carcinogens locally or act systemically, through c...

  3. Ethnicity and oral cancer.

    Scully, C; Bedi, R

    2000-09-01

    Oral squamous-cell carcinoma, the main type of oral cancer, is among the ten most common cancers in the world. The aims of this paper were first, to consider whether there was evidence of marked ethnic variations in the incidence, management, and survival of oral cancer, and then, to review possible explanations for these variations. Evidence from the literature suggests that there is marked, inter-country variation in both the incidence and mortality from oral cancer. There is also growing evidence of intracountry ethnic differences, mostly reported in the UK and USA. These variations among ethnic groups have been attributed mainly to specific risk factors, such as alcohol and tobacco (smoking and smokeless), but dietary factors and the existence of genetic predispositions may also play a part. Variations in access to care services are also an apparent factor. The extent of ethnic differences in oral cancer is masked by the scarcity of information available. Where such data are accessible, there are clear disparities in both incidence and mortality of oral cancer between ethnic groups.

  4. Emissions of greenhouse gases in the United States 1997

    NONE

    1998-10-01

    This is the sixth annual report on aggregate US national emissions of greenhouse gases. It covers emissions over the period 1990--1996, with preliminary estimates of emissions for 1997. Chapter one summarizes some background information about global climate change and the greenhouse effect. Important recent developments in global climate change activities are discussed, especially the third Conference of the Parties to the Framework Convention on Climate Change, which was held in December of 1997 in Kyoto, Japan. Chapters two through five cover emissions of carbon dioxide, methane, nitrous oxide, halocarbons and related gases, respectively. Chapter six describes potential sequestration and emissions of greenhouse gases as a result of land use changes. Six appendices are included in the report. 96 refs., 38 tabs.

  5. Thermodynamic properties of rotating trapped ideal Bose gases

    Li, Yushan; Gu, Qiang

    2014-01-01

    Ultracold atomic gases can be spined up either by confining them in rotating frame, or by introducing “synthetic” magnetic field. In this paper, thermodynamics of rotating ideal Bose gases are investigated within truncated-summation approach which keeps to take into account the discrete nature of energy levels, rather than to approximate the summation over single-particle energy levels by an integral as it does in semi-classical approximation. Our results show that Bose gases in rotating frame exhibit much stronger dependence on rotation frequency than those in “synthetic” magnetic field. Consequently, BEC can be more easily suppressed in rotating frame than in “synthetic” magnetic field.

  6. Hydrodynamics of Normal Atomic Gases with Spin-orbit Coupling.

    Hou, Yan-Hua; Yu, Zhenhua

    2015-10-20

    Successful realization of spin-orbit coupling in atomic gases by the NIST scheme opens the prospect of studying the effects of spin-orbit coupling on many-body physics in an unprecedentedly controllable way. Here we derive the linearized hydrodynamic equations for the normal atomic gases of the spin-orbit coupling by the NIST scheme with zero detuning. We show that the hydrodynamics of the system crucially depends on the momentum susceptibilities which can be modified by the spin-orbit coupling. We reveal the effects of the spin-orbit coupling on the sound velocities and the dipole mode frequency of the gases by applying our formalism to the ideal Fermi gas. We also discuss the generalization of our results to other situations.

  7. Emissions of exhaust gases and health of the person

    Germanova, Tatiana; Kernozhitskaya, Anna

    2017-10-01

    The auto-road complex brings the considerable contribution to pollution and adverse change of environment. Influence of exhaust gases of cars is at the bottom of occurrence and developments of various forms of diseases. Every townsman feels the negative influence rendered by motor transport on himself. The modern city dweller is so accustomed to the smell of exhaust gases that he does not even notice it at all, continues to breathe a poisonous mixture, while neither the car nor the road can be isolated from the habitats of people. The higher the population density, the higher the need for motor transport. The health effects of emissions of exhaust gases and vapors, including regulated and unregulated pollutants, are discussed in this article.

  8. A cluster dynamics study of fission gases in uranium dioxide

    Skorek, Richard

    2013-01-01

    During in-pile irradiation of nuclear fuels a lot of rare gases are produced, mainly xenon and krypton. The behaviour of these highly insoluble fission gases may lead to an additional load of the cladding, which may have detrimental safety consequences. For these reasons, fission gas behaviour (diffusion and clustering) has been extensively studied for years.In this work, we present an application of Cluster Dynamics to address the behaviour of fission gases in UO_2 which simultaneously describes changes in rare gas atom and point defect concentrations in addition to the bubble size distribution. This technique, applied to Kr implanted and annealed samples, yields a precise interpretation of the release curves and helps justifying the estimation of the Kr diffusion coefficient, which is a data very difficult to obtain due to the insolubility of the gas. (author) [fr

  9. Experimental Studies of CO2 Capturing from the Flue Gases

    Ehsan Rahmandoost

    2014-10-01

    Full Text Available CO2 emissions from combustion flue gases have turned into a major factor in global warming. Post-combustion carbon capture (PCC from industrial utility flue gases by reactive absorption can substantially reduce the emissions of the greenhouse gas CO2. To test a new solvent (AIT600 for this purpose, a small pilot plant was used. This paper presents the results of studies on chemical methods of absorbing CO2 from flue gases with the new solvent, and evaluates the effects of operating conditions on CO2 absorption efficiency. CO2 removal rate of the AIT600 solvent was higher in comparison to the conventional monoethanolamine (MEA solvent. The optimized temperature of the absorber column was 60 °C for CO2 absorption in this pilot plant. The overall absorption rate (Φ and the volumetric overall mass transfer coefficient (KGaV were also investigated.

  10. High-resolution spectroscopy of gases for industrial applications

    Fateev, Alexander; Clausen, Sønnik

    High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing...... databases (e.g. HITRAN, HITEMP or CDSD) can normally be used for absorption spectra calculations at limited temperature/pressure ranges. Therefore experimental measurements of absorption/transmission spectra gases (e.g. CO2, H2O or SO2) at high-resolution and elevated temperatures are essential both...... for analysis of complex experimental data and further development of the databases. High-temperature gas cell facilities available at DTU Chemical Engineering are presented and described. The gas cells and high-resolution spectrometers allow us to perform high-quality reference measurements of gases relevant...

  11. Holographic detection of hydrocarbon gases and other volatile organic compounds.

    Martínez-Hurtado, J L; Davidson, C A B; Blyth, J; Lowe, C R

    2010-10-05

    There is a need to develop sensors for real-time monitoring of volatile organic compounds (VOCs) and hydrocarbon gases in both external and indoor environments, since these compounds are of growing concern in human health and welfare. Current measurement technology for VOCs requires sophisticated equipment and lacks the prospect for rapid real-time monitoring. Holographic sensors can give a direct reading of the analyte concentration as a color change. We report a technique for recording holographic sensors by laser ablation of silver particles formed in situ by diffusion. This technique allows a readily available hydrophobic silicone elastomer to be transformed into an effective sensor for hydrocarbon gases and other volatile compounds. The intermolecular interactions present between the polymer and molecules are used to predict the sensor performance. The hydrophobicity of this material allows the sensor to operate without interference from water and other atmospheric gases and thus makes the sensor suitable for biomedical, industrial, or environmental analysis.

  12. Global warming description using Daisyworld model with greenhouse gases.

    Paiva, Susana L D; Savi, Marcelo A; Viola, Flavio M; Leiroz, Albino J K

    2014-11-01

    Daisyworld is an archetypal model of the earth that is able to describe the global regulation that can emerge from the interaction between life and environment. This article proposes a model based on the original Daisyworld considering greenhouse gases emission and absorption, allowing the description of the global warming phenomenon. Global and local analyses are discussed evaluating the influence of greenhouse gases in the planet dynamics. Numerical simulations are carried out showing the general qualitative behavior of the Daisyworld for different scenarios that includes solar luminosity variations and greenhouse gases effect. Nonlinear dynamics perspective is of concern discussing a way that helps the comprehension of the global warming phenomenon. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Determining air distribution during outbursts of gases and rocks

    Struminski, A; Sikora, M; Urbanski, J [Politechnika Wroclawska (Poland). Instytut Gornictwa

    1989-01-01

    Discusses use of the KPW-1 iterative and autocorrelation method developed by A. Struminski for forecasting effects of rock bursts on ventilation systems of underground coal mines with increased content of methane or carbon dioxide in coal seams and adjacent rock strata. The method is used for prediction of air flow changes caused by a rock burst accompanied by violent outburst of gases. Directions of air flow, flow rate and concentration of gases emitted from surrounding strata to mine workings are predicted. On the basis of this prediction concentration of gases from a coal outburst is determined for any point in a ventilation network. The prediction method is used for assessing hazards for coal mines during and after a rock burst. Use of the method is explained on the example of the Thorez and Walbrzych coal mines. Computer programs developed for ODRA and IBM/XT computers are discussed. 6 refs.

  14. μ+ thermalization and muonium formation in noble gases

    Fleming, D.G.; Mikula, R.J.; Garner, D.M.; British Columbia Univ., Vancouver

    1981-01-01

    One energy loss mechanism in μ + thermalization (in gases) is that due to charge exchange, in which muonium is repeatedly formed and lost in a series of charge-exchange cycles μ + +e - reversible Mu, a process which depends on the ionization potential of the moderator gas but one in which no depolarization of the μ + is expected at approx. 1 atm. pressure. However, if the time between collisions in a given energy regime can be made sufficiently long then additional depolarization may occur, which can provide further information on the charge-exchange process itself. Extensive data showing this effect has been found in gases; results for the noble gases are presented. (orig.)

  15. Multisensor system for toxic gases detection generated on indoor environments

    Durán, C. M.; Monsalve, P. A. G.; Mosquera, C. J.

    2016-11-01

    This work describes a wireless multisensory system for different toxic gases detection generated on indoor environments (i.e., Underground coal mines, etc.). The artificial multisensory system proposed in this study was developed through a set of six chemical gas sensors (MQ) of low cost with overlapping sensitivities to detect hazardous gases in the air. A statistical parameter was implemented to the data set and two pattern recognition methods such as Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA) were used for feature selection. The toxic gases categories were classified with a Probabilistic Neural Network (PNN) in order to validate the results previously obtained. The tests were carried out to verify feasibility of the application through a wireless communication model which allowed to monitor and store the information of the sensor signals for the appropriate analysis. The success rate in the measures discrimination was 100%, using an artificial neural network where leave-one-out was used as cross validation method.

  16. Sampling and analysis methods for geothermal fluids and gases

    Watson, J.C.

    1978-07-01

    The sampling procedures for geothermal fluids and gases include: sampling hot springs, fumaroles, etc.; sampling condensed brine and entrained gases; sampling steam-lines; low pressure separator systems; high pressure separator systems; two-phase sampling; downhole samplers; and miscellaneous methods. The recommended analytical methods compiled here cover physical properties, dissolved solids, and dissolved and entrained gases. The sequences of methods listed for each parameter are: wet chemical, gravimetric, colorimetric, electrode, atomic absorption, flame emission, x-ray fluorescence, inductively coupled plasma-atomic emission spectroscopy, ion exchange chromatography, spark source mass spectrometry, neutron activation analysis, and emission spectrometry. Material on correction of brine component concentrations for steam loss during flashing is presented. (MHR)

  17. Opportunity to reduce the exhaust gases with engine adjust

    Dimitrovski, Mile; Mucevski, Kiril

    2002-01-01

    According to statistics in the Republic of Macedonia, the number of old vehicles is about 90%. These are vehicles produced between 1975 and 1990 with classical systems for forming and burning the fuel mixture. The most of them do not have system for processing exhaust gases (catalytic converter) and are serious air pollutants of carbon monoxide (CO). In this article we try to make an attempt to reduce exhaust gases in some kinds of these vehicles with adjusting to the system for burning fuel mixture and with adjusting to the system for forming fuel mixture (carburetor). At the same time the changes on the rotate bending moment and engine power are followed. It is noticed that with a proper adjustment the emission of exhaust gases can be reduced without a serious depreciation of the rotate bending moment and the engine power. (Author)

  18. A route to ultrathin quantum gases at polar perovskite heterointerfaces

    Nazir, Safdar

    2012-09-07

    Oxide interfaces are attracting interest in recent years due to special functionalities of two-dimensional quantum gases. However, with typical thicknesses of at least 10-12 Å the gases still extend considerably in the third dimension, which compromises the size of quantum effects. To overcome this limitation, we propose incorporation of highly electronegative cations, such as Ag. By ab initio calculations, we demonstrate the formation of a mobile two-dimensional hole gas in AgNbO 3/SrTiO 3 that is confined to an ultrathin slab of only 5.6 Å thickness. Electronegative cations therefore are a promising way to enhance the quantum nature of hole gases. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Head, Neck, and Oral Cancer

    Full Text Available ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  20. Head, Neck, and Oral Cancer

    ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  1. Adsorption of Dissolved Gases (CH4, CO2, H2, Noble Gases) by Water-Saturated Smectite Clay Minerals

    Bourg, I. C.; Gadikota, G.; Dazas, B.

    2016-12-01

    Adsorption of dissolved gases by water-saturated clay minerals plays important roles in a range of fields. For example, gas adsorption in on clay minerals may significantly impact the formation of CH4 hydrates in fine-grained sediments, the behavior of CH4 in shale, CO2 leakage across caprocks of geologic CO2 sequestration sites, H2 leakage across engineered clay barriers of high-level radioactive waste repositories, and noble gas geochemistry reconstructions of hydrocarbon migration in the subsurface. Despite its importance, the adsorption of gases on clay minerals remains poorly understood. For example, some studies have suggested that clay surfaces promote the formation of CH4 hydrates, whereas others indicate that clay surfaces inhibit the formation of CH4 hydrates. Here, we present molecular dynamics (MD) simulations of the adsorption of a range of gases (CH4, CO2, H2, noble gases) on clay mineral surfaces. Our results indicate that the affinity of dissolved gases for clay mineral surfaces has a non-monotone dependence on the hydrated radius of the gas molecules. This non-monotone dependence arises from a combination of two effects: the polar nature of certain gas molecules (in particular, CO2) and the templating of interfacial water structure by the clay basal surface, which results in the presence of interfacial water "cages" of optimal size for intermediate-size gas molecules (such as Ne or Ar).

  2. Radiolytic and thermal generation of gases from Hanford grout samples

    Meisel, D.; Jonah, C.D.; Kapoor, S.; Matheson, M.S.; Mulac, W.A.

    1993-10-01

    Gamma irradiation of WHC-supplied samples of grouted Tank 102-AP simulated nonradioactive waste has been carried out at three dose rates, 0.25, 0.63, and 130 krad/hr. The low dose rate corresponds to that in the actual grout vaults; with the high dose rate, doses equivalent to more than 40 years in the grout vault were achieved. An average G(H{sub 2}) = 0.047 molecules/100 eV was found, independent of dose rate. The rate of H2 production decreases above 80 Mrad. For other gases, G(N{sub 2}) = 0.12, G(O{sub 2}) = 0.026, G(N{sub 2}O) = 0.011 and G(CO) = 0.0042 at 130 krad/hr were determined. At lower dose rates, N{sub 2} and O{sub 2} could not be measured because of interference by trapped air. The value of G(H{sub 2}) is higher than expected, suggesting segregation of water from nitrate and nitrite salts in the grout. The total pressure generated by the radiolysis at 130 krad/h has been independently measured, and total amounts of gases generated were calculated from this measurement. Good agreement between this measurement and the sum of all the gases that were independently determined was obtained. Therefore, the individual gas measurements account for most of the major components that are generated by the radiolysis. At 90 {degree}C, H{sub 2}, N{sub 2}, and N{sub 2}O were generated at a rate that could be described by exponential formation of each of the gases. Gases measured at the lower temperatures were probably residual trapped gases. An as yet unknown product interfered with oxygen determinations at temperatures above ambient. The thermal results do not affect the radiolytic findings.

  3. Unmanned Aerial Systems for Monitoring Trace Tropospheric Gases

    Travis J. Schuyler

    2017-10-01

    Full Text Available The emission of greenhouse gases (GHGs has changed the composition of the atmosphere during the Anthropocene. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating the contributions of different processes to radiative forcing. Currently there is no mobile platform that is able to quantify trace gases at altitudes <100 m above ground level that can achieve spatiotemporal resolution on the order of meters and seconds. Unmanned aerial systems (UASs can be deployed on-site in minutes and can support the payloads necessary to quantify trace gases. Therefore, current efforts combine the use of UASs available on the civilian market with inexpensively designed analytical systems for monitoring atmospheric trace gases. In this context, this perspective introduces the most relevant classes of UASs available and evaluates their suitability to operate three kinds of detectors for atmospheric trace gases. The three subsets of UASs discussed are: (1 micro aerial vehicles (MAVs; (2 vertical take-off and landing (VTOL; and, (3 low-altitude short endurance (LASE systems. The trace gas detectors evaluated are first the vertical cavity surface emitting laser (VCSEL, which is an infrared laser-absorption technique; second two types of metal-oxide semiconductor sensors; and, third a modified catalytic type sensor. UASs with wingspans under 3 m that can carry up to 5 kg a few hundred meters high for at least 30 min provide the best cost and convenience compromise for sensors deployment. Future efforts should be focused on the calibration and validation of lightweight analytical systems mounted on UASs for quantifying trace atmospheric gases. In conclusion, UASs offer new and exciting opportunities to study atmospheric composition and its effect on weather patterns and climate change.

  4. Method of distillation of sulfurous bituminous shales

    Hallback, A J.S.; Bergh, S V

    1918-04-22

    A method of distillation of sulfur-containing bituminous shales is characterized by passing the hot sulfur-containing and oil-containing gases and vapors formed during the distillation through burned shale containing iron oxide, so that when these gases and vapors are thereafter cooled they will be, as far as possible, free from sulfur compounds. The patent contains six more claims.

  5. Strengthening of oral health systems

    Petersen, Poul Erik

    2014-01-01

    is either due to low availability and accessibility of oral health care or because oral health care is costly. In all countries, the poor and disadvantaged population groups are heavily affected by a high burden of oral disease compared to well-off people. Promotion of oral health and prevention of oral...... diseases must be provided through financially fair primary health care and public health intervention. Integrated approaches are the most cost-effective and realistic way to close the gap in oral health between rich and poor. The World Health Organization (WHO) Oral Health Programme will work......Around the globe many people are suffering from oral pain and other problems of the mouth or teeth. This public health problem is growing rapidly in developing countries where oral health services are limited. Significant proportions of people are underserved; insufficient oral health care...

  6. GAZVIL - Gases and gas mixtures for welding in protective medium

    Avram, I.; Constantin, N.; Cristescu, I.; Stefan, L.; Zamfirache, M.

    1996-01-01

    Gases and gas mixtures are used in machine building industry as protective environment in the welding by the procedures: MIG, MAG, TIG, plasma and micro-plasma. Also they are used in jet plasma production as well as controlled environment in materials heat treatments, passivation or protective procedures of equipment of chemical and petrochemical industries. Gases and gas mixtures are obtained in particular quality conditions while their purity is certified by specific methods making use of performing technology in laboratories to be qualified in the frame of the RELAR system

  7. Universal relaxation times for electron and nucleon gases

    Pelc, M.; Marciak-Kozlowska, J.; Kozlowski, M.

    2007-01-01

    In this paper we calculate the universal relaxation times for electron and nucleon fermionic gases. We argue that the universal relaxation time tau(i) is equal tau(i)=h/m square v(i) where v(i)=alpha(i)c and alpha(1)=0.15 for nucleon gas and alpha(2)=1/137 for electron gas, c=light velocity. With the universal relaxation time we formulate the thermal Proca equation for fermionic gases. Key words: universal relaxation time, thermal universal Proca equation.

  8. Damping of multispan heat exchanger tubes. Pt. 1: in gases

    Pettigrew, M.J.; Goyder, H.G.D.; Qiao, Z.L.; Axisa, F.

    1986-07-01

    Flow-induced vibration analyses of heat exchanger tubes require the knowledge of damping. This paper treats the question of damping on multispan heat exchanger tubes in air and gases. The different energy dissipation mechanisms that contribute to tube damping are discussed. The available experimental data are reviewed and analysed. We find that the main damping mechanism in gases is friction between tube and tube-supports. Damping is strongly related to tube-support thickness. Damping values are recommended for design purposes. This study is interesting in the nuclear industry for it often uses heat exchangers

  9. Greenhouse effect of trace gases, 1970-1980

    Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

    1981-01-01

    Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

  10. On the relativistic partition function of ideal gases

    Sinyukov, Yu.M.

    1983-01-01

    The covariant partition function method for ideal Boltzmann and Bose gases is developed within quantum field theory. This method is a basis to describe the statistical and thermodynamical properties of the gases in canonical, grand canonical and pressure ensembles in an arbitrary inertial system. It is shown that when statistical systems are described relativistically it is very important to take into account the boundary conditions. This is due to the fact that an equilibrium system is not closed mechanically. The results may find application in hadron physics. (orig.)

  11. Removal of sulfur and nitrogen containing pollutants from discharge gases

    Joubert, James I. (Pittsburgh, PA)

    1986-01-01

    Oxides of sulfur and of nitrogen are removed from waste gases by reaction with an unsupported copper oxide powder to form copper sulfate. The resulting copper sulfate is dissolved in water to effect separation from insoluble mineral ash and dried to form solid copper sulfate pentahydrate. This solid sulfate is thermally decomposed to finely divided copper oxide powder with high specific surface area. The copper oxide powder is recycled into contact with the waste gases requiring cleanup. A reducing gas can be introduced to convert the oxide of nitrogen pollutants to nitrogen.

  12. Removal of sulfur and nitrogen containing pollutants from discharge gases

    Joubert, J.I.

    1985-02-08

    Oxides of sulfur and of nitrogen are removed from waste gases by reaction with an unsupported copper oxide powder to form copper sulfate. The resulting copper sulfate is dissolved in water to effect separation from insoluble mineral ash and dried to form solid copper sulfate pentahydrate. This solid sulfate is thermally decomposed to finely divided copper oxide powder with high specific surface area. The copper oxide powder is recycled into contact with the waste gases requiring cleanup. A reducing gas can be introduced to convert the oxide of nitrogen pollutants to nitrogen.

  13. Device for adsorbing exhaled radioactive gases and process

    Glasser, H.; Panetta, P.F.

    1976-01-01

    Sorption means are provided for sorbing radioactive gases, as in the exhalations of a living subject, especially for nuclear diagnostic test studies, comprising means for adsorbing the radioactive gas onto activated carbon, the carbon being contained in a plurality of independent, series-connected, chambers. The sorption means are especially adapted for the adsorption of radioactive inert gases such as xenon-133 ( 133 Xe). There can also be provided indicator means for indicating the flow-through of xenon comprising an indicator which changes color upon contact with xenon, such as dioxygenylhexafluoroantimoniate. 14 claims, 7 drawing figures

  14. Change in the atmospheric concentration of greenhouse gases

    GARREC, Jean-Pierre

    2000-01-01

    With the constant increase in industrial and agricultural activities since the beginning of the 20. Century, human societies have altered the chemical composition of the atmosphere both in their immediate vicinity and further afar. The most preoccupying problem today is the increase in the so-called greenhouse gases (CO 2 , CH 4 , N 2 O, CFC, O 3 ). Indeed, these pollutant gases generally have long life cycles and consequently have for the first time produced a change in the composition of the atmosphere on a global scale inducing deferred effects such as a likely change in the earth's climate. (author)

  15. Detection of gases and gas mixtures by correlation spectroscopy

    Dakin, J.P.; Gunning, M.J.; Chambers, P.

    2002-01-01

    The reliable detection and monitoring of gases and gas mixtures is known to play a crucial role in many real-world environmental and industrial applications. It is of considerable importance to utilise techniques that are not susceptible to poisoning, are specific to a target gas in a mixture, are unaffected by contaminants, and can be adapted for in-process monitoring. Ever-more stringent requirements in this field dictate a need for ongoing research in this area. As many common gases exhibi...

  16. Capacitors on the basis of intercalate GaSe

    Kovalyuk Z. D.

    2010-06-01

    Full Text Available The compound GaSe is obtained by the technique of intercalation of a GaSe single crystal in a melt of the ferroelectric salt KNO3. The x-ray analysis of its crystal structure has been carried out and dielectric frequency characteristics of samples has been measured. It is estab-lished, that accumulation of electric charges occurs in the examined examples in frequency area 100—1000 Hz. A sample of filter capacitor has been created on the basis of the re-ceived compounds.

  17. Measurement of Selected Organic Trace Gases During TRACE-P

    Atlas, Elliot

    2004-01-01

    Major goals of the TRACE-P mission were: 1) to investigate the chemical composition of radiatively important gases, aerosols, and their precursors in the Asian outflow over the western Pacific, and 2) to describe and understand the chemical evolution of the Asian outflow as it is transported and mixed into the global troposphere. The research performed as part of this proposal addressed these major goals with a study of the organic chemical composition of gases in the TRACE-P region. This work was a close collaboration with the Blake/Rowland research group at UC-Irvine, and they have provided a separate report for their funded effort.

  18. Cost-effectiveness in the mitigation of green house gases

    Rey, Francisco Carlos

    2009-01-01

    This paper analyzes the cost-effectiveness in the mitigation of green house gases from solar, eolic and nuclear energy sources, concluding that nuclear is, not doubt, the mos efficient. On the other hand, nuclear is the unique source that can be installed without limit in magnitude and in the proximity of the demand, and is for all these reasons that several environmental referents in the world have changed their perception on this source and defend it as the unique actual alternative to fight against the emission of green house gases. (author) [es

  19. Thermodynamics, Gibbs Method and Statistical Physics of Electron Gases Gibbs Method and Statistical Physics of Electron Gases

    Askerov, Bahram M

    2010-01-01

    This book deals with theoretical thermodynamics and the statistical physics of electron and particle gases. While treating the laws of thermodynamics from both classical and quantum theoretical viewpoints, it posits that the basis of the statistical theory of macroscopic properties of a system is the microcanonical distribution of isolated systems, from which all canonical distributions stem. To calculate the free energy, the Gibbs method is applied to ideal and non-ideal gases, and also to a crystalline solid. Considerable attention is paid to the Fermi-Dirac and Bose-Einstein quantum statistics and its application to different quantum gases, and electron gas in both metals and semiconductors is considered in a nonequilibrium state. A separate chapter treats the statistical theory of thermodynamic properties of an electron gas in a quantizing magnetic field.

  20. ORAL MYIASIS CONVERTING TO ORAL SQUAMOUS CELL CARCINOMA

    Akshay

    2015-10-01

    Full Text Available INTRODUCTION: Oral Myiasis, a condition of infestation of the body by fly larvae (maggots is a rare pathology in humans. It is associated with poor oral hygiene, alcoholism, senility, suppurating lesions, severe halitosis. It is seen frequently in tropical countries and hot climatic regions. The reported cases in literature of oral Myiasis associated with oral cancer are few. The treatment is a mechanical removal of the maggots but a systemic treatment with Ivermectin, a semi - synthetic macrolide antibiotic, has been used successfully for treatment for oral m yiasis. We present a case of 55 yr old male alcoholic patient with oral myiasis with extensive proliferative growth of oral cavity. Our patient was managed with manual debridement and administration of systemic ivermect in along with antibiotic coverage. Incisional biopsy of the proliferative lesion showed well differentiated squamous cell carcinoma. Thus our patient showed presence of oral myiasis in association with oral squamous cell carcinoma.

  1. Greenhouse gases study in Amazonia; Estudo de gases de efeito estufa na Amazonia

    D' Amelio, Monica Tais Siqueira

    2006-07-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO{sub 2} sources. The Amazon forest is a significant source of N{sub 2}O by soil process, and CH{sub 4} by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO{sub 2}, CH{sub 4}, CO, H{sub 2}, N{sub 2}O and SF{sub 6} have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO{sub 2} flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO{sub 2} flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H{sub 2} gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO{sub 2} sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that

  2. Greenhouse gases study in Amazonia; Estudo de gases de efeito estufa na Amazonia

    D' Amelio, Monica Tais Siqueira

    2006-07-01

    The Amazon plays an important role on the global carbon cycle, as changing as carbon storage, since Amazon Basin is the biggest area of tropical forest, around 50% of global. Natural's process, deforestation, and use land are CO{sub 2} sources. The Amazon forest is a significant source of N{sub 2}O by soil process, and CH{sub 4} by anaerobic process like flooded areas, rice cultures, and others sources. This project is part of the LBA project (Large-Scale Biosphere Atmosphere Experiment in Amazonia), and this project is 'Vertical profiles of carbon dioxide and other trace gas species over the Amazon basin using small aircraft'. Since December 2000 vertical profiles of CO{sub 2}, CH{sub 4}, CO, H{sub 2}, N{sub 2}O and SF{sub 6} have been measured above central Amazonia. The local sampling was over Tapajos National Forest, a primary forest in Para State, where had a CO{sub 2} flux tower and an east impact area with sources like animals, rice cultivation, biomass burning, etc, to compare the influence of an impact area and a preserved area in the profiles. The Reserva Biologica de Cuieiras, at Amazon State, is the other studied place, where there already exists a CO{sub 2} flux tower, and an east preserved area at this State, to compare with the Cuieiras. The sampling has been carried out on vertical profile from 1000 ft up to 12000 ft using a semi-automated sampling package developed at GMD/NOAA and a small aircraft. The analysis uses the MAGICC system (Multiple Analysis of Gases Influence Climate Change) which is installed at the Atmospheric Chemistry Laboratory (LQA) in IPEN (Instituto de Pesquisas Energeticas e Nucleares). The results showed that all gases studied, except H{sub 2} gas, has been following the global trend. At the Para State, for the studied years, the Amazonian Forest performed as small CO{sub 2} sink. To compare Wet and Dry Seasons, subtracted the Ascension concentration values in the period to remove the global influence. So that, in the 2004 and

  3. Communication among Oral Bacteria

    Kolenbrander, Paul E.; Andersen, Roxanna N.; Blehert, David S.; Egland, Paul G.; Foster, Jamie S.; Palmer, Robert J.

    2002-01-01

    Human oral bacteria interact with their environment by attaching to surfaces and establishing mixed-species communities. As each bacterial cell attaches, it forms a new surface to which other cells can adhere. Adherence and community development are spatiotemporal; such order requires communication. The discovery of soluble signals, such as autoinducer-2, that may be exchanged within multispecies communities to convey information between organisms has emerged as a new research direction. Direct-contact signals, such as adhesins and receptors, that elicit changes in gene expression after cell-cell contact and biofilm growth are also an active research area. Considering that the majority of oral bacteria are organized in dense three-dimensional biofilms on teeth, confocal microscopy and fluorescently labeled probes provide valuable approaches for investigating the architecture of these organized communities in situ. Oral biofilms are readily accessible to microbiologists and are excellent model systems for studies of microbial communication. One attractive model system is a saliva-coated flowcell with oral bacterial biofilms growing on saliva as the sole nutrient source; an intergeneric mutualism is discussed. Several oral bacterial species are amenable to genetic manipulation for molecular characterization of communication both among bacteria and between bacteria and the host. A successful search for genes critical for mixed-species community organization will be accomplished only when it is conducted with mixed-species communities. PMID:12209001

  4. [Oral health in pregnancy].

    Blagojević, Duska; Brkanić, Tatjana; Stojić, Sinisa

    2002-01-01

    Good oral health care during pregnancy is essential but often overlooked factor of dental growth as well as of other structures of oral cavity. Pregnancy is the time when conscious approach to preventive oral care should increase. Preventive measures during pregnancy mean usage of fluorides, special dietary measures and increased oral hygiene habits. Preventive measures in pregnant women have one goal: providing conditions for development of fetal teeth as well as preventing tooth decay in pregnant women. The optimal period for introducing preventive measures is the first trimester of pregnancy. Because of hormonal alterations there is an increased incidence of dental diseases: gingivitis and low salivary pH (inflammation and bleeding gums). Eating habits of pregnant women may lead to frequent snacking on candy or other decay-promoting foods, thereby increasing the risk of caries. However, very poor oral health, possible dental complications and their consequences to the health as well as emotional status represent very strong reasons for activation of dental health care in this period.

  5. The Oral Microbiota.

    Arweiler, Nicole B; Netuschil, Lutz

    2016-01-01

    The oral microbiota represents an important part of the human microbiota, and includes several hundred to several thousand diverse species. It is a normal part of the oral cavity and has an important function to protect against colonization of extrinsic bacteria which could affect systemic health. On the other hand, the most common oral diseases caries, gingivitis and periodontitis are based on microorganisms. While (medical) research focused on the planktonic phase of bacteria over the last 100 years, it is nowadays generally known, that oral microorganisms are organised as biofilms. On any non-shedding surfaces of the oral cavity dental plaque starts to form, which meets all criteria for a microbial biofilm and is subject to the so-called succession. When the sensitive ecosystem turns out of balance - either by overload or weak immune system - it becomes a challenge for local or systemic health. Therefore, the most common strategy and the golden standard for the prevention of caries, gingivitis and periodontitis is the mechanical removal of this biofilms from teeth, restorations or dental prosthesis by regular toothbrushing.

  6. Oral health during pregnancy.

    Silk, Hugh; Douglass, Alan B; Douglass, Joanna M; Silk, Laura

    2008-04-15

    Oral health care in pregnancy is often avoided and misunderstood by physicians, dentists, and patients. Evidence-based practice guidelines are still being developed. Research suggests that some prenatal oral conditions may have adverse consequences for the child. Periodontitis is associated with preterm birth and low birth weight, and high levels of cariogenic bacteria in mothers can lead to increased dental caries in the infant. Other oral lesions, such as gingivitis and pregnancy tumors, are benign and require only reassurance and monitoring. Every pregnant woman should be screened for oral risks, counseled on proper oral hygiene, and referred for dental treatment when necessary. Dental procedures such as diagnostic radiography, periodontal treatment, restorations, and extractions are safe and are best performed during the second trimester. Xylitol and chlorhexidine may be used as adjuvant therapy for high-risk mothers in the early postpartum period to reduce transmission of cariogenic bacteria to their infants. Appropriate dental care and prevention during pregnancy may reduce poor prenatal outcomes and decrease infant caries.

  7. Canine oral melanoma.

    Bergman, Philip J

    2007-05-01

    Melanoma is the most common oral malignancy in the dog. Oral and/or mucosal melanoma has been routinely considered an extremely malignant tumor with a high degree of local invasiveness and high metastatic propensity. Primary tumor size has been found to be extremely prognostic. The World Health Organization staging scheme for dogs with oral melanoma is based on size, with stage I = or = 4cm tumor and/or lymph node metastasis, and stage IV = distant metastasis. Median survival times for dogs with oral melanoma treated with surgery are approximately 17 to 18, 5 to 6, and 3 months with stage I, II, and III disease, respectively. Significant negative prognostic factors include stage, size, evidence of metastasis, and a variety of histologic criteria. Standardized treatments such as surgery, coarse-fractionation radiation therapy, and chemotherapy have afforded minimal to modest stage-dependent clinical benefits and death is usually due to systemic metastasis. Numerous immunotherapeutic strategies have been employed to date with limited clinical efficacy; however, the use of xenogeneic DNA vaccines may represent a leap forward in clinical efficacy. Oral melanoma is a spontaneous syngeneic cancer occurring in outbred, immunocompetent dogs and appears to be a more clinically faithful therapeutic model for human melanoma; further use of canine melanoma as a therapeutic model for human melanoma is strongly encouraged. In addition, the development of an expanded but clinically relevant staging system incorporating the aforementioned prognostic factors is also strongly encouraged.

  8. Emission and Sink of Greenhouse Gases in Soils of Moscow

    Mozharova, N. V.; Kulachkova, S. A.; Lebed'-Sharlevich, Ya. I.

    2018-03-01

    The first inventory and zoning of the emission and sink of methane and carbon dioxide in the urban structure of greenhouse gases from soils and surface technogenic formations (STFs) (Technosols) on technogenic, recrementogenic, and natural sediments have been performed with consideration for the global warming potential under conditions of different formation rate of these gases, underflooding, and sealing. From gas geochemical criteria and anthropogenic pedogenesis features, the main sources of greenhouse gases, their intensity, and mass emission were revealed. The mass fractions of emissions from the sectors of waste and land use in the inventories of greenhouse gas emissions have been determined. New sources of gas emission have been revealed in the first sector, the emissions from which add tens of percent to the literature and state reports. In the second sector, emissions exceed the available data in 70 times. Estimation criteria based on the degree of manifestation and chemical composition of soil-geochemical anomalies and barrier capacities have been proposed. The sink of greenhouse gases from the atmosphere and the internal (latent) sink of methane in soils and STFs have been determined. Ecological functions of soils and STFs have been shown, and the share of latent methane sink has been calculated. The bacterial oxidation of methane in soils and STFs exceeds its emission to the atmosphere in almost hundred times.

  9. EOSN: A TOUGH2 module for noble gases

    Shan, Chao; Pruess, Karsten

    2003-01-01

    We developed a new fluid property module for TOUGH2, called EOSN, to simulate transport of noble gases in the subsurface. Currently, users may select any of five different noble gases as well as CO2, two at a time. For the three gas components (air and two user-specified noble gases) in EOSN, the Henry's coefficients and the diffusivities in the gas phase are no longer assumed constants, but are temperature dependent. We used the Crovetto et al. (1982) model to estimate Henry's coefficients, and the Reid et al. (1987) correlations to calculate gas phase diffusivities. The new module requires users to provide names of the selected noble gases, which properties are provided internally. There are options for users to specify any (non-zero) molecular weights and half-lives for the gas components. We provide two examples to show applications of TOUGH2IEOSN. While temperature effects are relatively insignificant for one example problem where advection is dominant, they cause almost an order of magnitude difference for the other case where diffusion becomes a dominant process and temperature variations are relatively large. It appears that thermodynamic effects on gas diffusivities and Henry's coefficients can be important for low-permeability porous media and zones with large temperature variations

  10. Spectrum of spin waves in cold polarized gases

    Andreeva, T. L., E-mail: phdocandreeva@yandex.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-02-15

    The spin dynamics of cold polarized gases are investigated using the Boltzmann equation. The dispersion relation for spin waves (transverse component of the magnetic moment) and the spin diffusion coefficient of the longitudinal component of the magnetic moment are calculated without using fitting parameters. The spin wave frequency and the diffusion coefficient for rubidium atoms are estimated numerically.

  11. A route to ultrathin quantum gases at polar perovskite heterointerfaces

    Nazir, Safdar; Schwingenschlö gl, Udo

    2012-01-01

    that is confined to an ultrathin slab of only 5.6 Å thickness. Electronegative cations therefore are a promising way to enhance the quantum nature of hole gases. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Interaction effects on dynamic correlations in noncondensed Bose gases

    Bezett, A.; Van Driel, H. J.; Mink, M. P.; Stoof, H. T C; Duine, R. A.

    2014-01-01

    We consider dynamic, i.e., frequency-dependent, correlations in noncondensed ultracold atomic Bose gases. In particular, we consider the single-particle correlation function and its power spectrum. We compute this power spectrum for a one-component Bose gas, and we show how it depends on the

  13. Atomtronics: Material and Device Physics of Quantum Gases

    matter physics to electrical engineering. Our projects title Atomtronics: Material and device physics of quantum gases illustrates the chasm we bridged...starting from therich and fundamental physics already revealed with cold atoms systems, then leading to an understanding of the functional materials

  14. The greenhouse effect gases; Les gaz a effet de serre

    NONE

    2006-06-15

    This road-map proposes by the Group Total aims to inform the public on the greenhouse effect gases. It presents the greenhouses effect as a key component of the climate system, the impacts of the human activity, the foreseeable consequences of global warming, the Kyoto protocol and Total commitment in the domain. (A.L.B.)

  15. EOSN: A TOUGH2 module for noble gases

    Shan, Chao; Pruess, Karsten

    2003-03-07

    We developed a new fluid property module for TOUGH2, called EOSN, to simulate transport of noble gases in the subsurface. Currently, users may select any of five different noble gases as well as CO2, two at a time. For the three gas components (air and two user-specified noble gases) in EOSN, the Henry's coefficients and the diffusivities in the gas phase are no longer assumed constants, but are temperature dependent. We used the Crovetto et al. (1982) model to estimate Henry's coefficients, and the Reid et al. (1987) correlations to calculate gas phase diffusivities. The new module requires users to provide names of the selected noble gases, which properties are provided internally. There are options for users to specify any (non-zero) molecular weights and half-lives for the gas components. We provide two examples to show applications of TOUGH2IEOSN. While temperature effects are relatively insignificant for one example problem where advection is dominant, they cause almost an order of magnitude difference for the other case where diffusion becomes a dominant process and temperature variations are relatively large. It appears that thermodynamic effects on gas diffusivities and Henry's coefficients can be important for low-permeability porous media and zones with large temperature variations.

  16. Inventory of greenhouse gases emissions from gasoline and diesel ...

    Emissions from fossil fuel combustion are of global concern due to their negative effects on public health and environment. This paper is an inventory of the greenhouse gases (GHGs) released into the environment through consumption of fuels (gasoline and diesel) in Nigeria from 1980 to 2014. The fuel consumption data ...

  17. Quantum statistics of ideal gases in confined space

    Dai, Wu-Sheng; Xie, Mi

    2002-01-01

    In this paper, the effects of boundary and connectivity on ideal gases in two-dimensional confined space and three-dimensional tubes are discussed in detail based on the analytical result. The implication of such effects on the mesoscopic system is also revealed.

  18. Kinetic Theory Derivation of the Adiabatic Law for Ideal Gases.

    Sobel, Michael I.

    1980-01-01

    Discusses how the adiabatic law for ideal gases can be derived from the assumption of a Maxwell-Boltzmann (or any other) distribution of velocities--in contrast to the usual derivations from thermodynamics alone, and the higher-order effect that leads to one-body viscosity. An elementary derivation of the adiabatic law is given. (Author/DS)

  19. Quantum information entropies of ultracold atomic gases in a ...

    The position and momentum space information entropies of weakly interacting trapped atomic Bose–Einstein condensates and spin-polarized trapped atomic Fermi gases at absolute zero temperature are evaluated. We find that sum of the position and momentum space information entropies of these quantum systems ...

  20. Quantum statistics of ideal gases in confined space

    Dai Wusheng; Xie Mi

    2003-01-01

    In this Letter, the effects of boundary and connectivity on ideal gases in two-dimensional confined space and three-dimensional tubes are discussed in detail based on the analytical result. The implication of such effects on the mesoscopic system is also revealed

  1. Quantum information entropies of ultracold atomic gases in a ...

    bosonic systems and a ≃ 1.982 and b = 1 for ideal fermionic systems. These results obey the entropic uncertainty relation given by Beckner, Bialynicki-Birula and Myceilski. Keywords. Ultracold atomic gases; information entropy; foundations of quantum mechanics. PACS Nos 67.85.−d; 89.70.Cf; 03.65.Ta. 1. Introduction.

  2. Rare gases adsorption and separation on silver doped adsorbent

    Deliere, Ludovic

    2015-01-01

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) implements means for detecting nuclear tests in an International Monitoring System (IMS). The Commissariat a l'Energie Atomique et aux Energies Alternatives (CEA) has developed in the mid-90's, the SPALAX system (Systeme de Prelevement d'Air en Ligne avec l'Analyse des radioXenons). Xenon analysis, including radioactive isotopes from the fission reaction during the explosion, requires the development of highly efficient process for xenon concentration. In this work, the adsorption and diffusion phenomena of noble gases are studied in silver exchanged ZSM-5 zeolite. The 'experience/Monte Carlo simulation' coupling is used to determine the essential thermodynamic data on the adsorption of noble gases and to characterize the adsorption sites. The presence of a strong adsorption site, identified as silver nanoparticles and intervening at low concentration of noble gases (including xenon and radon) in some silver exchanged zeolites, achieves adsorption and selectivity performance to date unrivaled. These results allow considering their use in many critical applications in the field of capture and separation of rare gases: rare gas industrial production, reprocessing of spent fuel from gas, radon in air pollution control. (author) [fr

  3. Caldera de recuperación de gases perdidos

    Camacho Thielepape, Daniel José

    2011-01-01

    El objeto de este proyecto es describir las instalaciones de la caldera de recuperación de gases perdidos. Más concretamente, las instalaciones de una nueva Planta de Reciclado de Aceite Lubricante en el Campo de Gibraltar, ubicada en el Polígono Industrial del término municipal de San Roque (Cádiz).

  4. Device for determining heat capacity of gases and gas mixtures

    Nachev, N

    1980-01-01

    This article describes the use of a capillary-flow colorimeter to determine the heat capacity of gases and gaseous mixtures. The research and tests confirm the possibility and advisability of making these measurements. The calorimeters are graduated to allow for the influence of the pressure and temperature of the investigated gas and exchange with the environment.

  5. 75 FR 66433 - Mandatory Reporting of Greenhouse Gases

    2010-10-28

    ... Part II Environmental Protection Agency 40 CFR Parts 86 and 98 Mandatory Reporting of Greenhouse...; FRL-9213-5] RIN 2060-A079 Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection... Mandatory Greenhouse Gas Reporting rule to correct certain technical and editorial errors that have been...

  6. 75 FR 33949 - Mandatory Reporting of Greenhouse Gases

    2010-06-15

    ... Part III Environmental Protection Agency 40 CFR Parts 86 and 98 Mandatory Reporting of Greenhouse...; FRL-9158-6] RIN 2060-A079 Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection... Final Mandatory Greenhouse Gas Reporting rule (2009 Final MRR) to correct certain technical and...

  7. 75 FR 18455 - Mandatory Reporting of Greenhouse Gases

    2010-04-12

    ... Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule amendment. SUMMARY: EPA is proposing to amend the Mandatory Greenhouse Gas (GHG) Reporting Rule, to require.... The Mandatory GHG Reporting Rule requires greenhouse gas emitting facilities and suppliers of fuels...

  8. Desulfurization of waste gases of the incinerator after petroleum refining

    Samesova, D.; Ladomersky, J.

    2001-01-01

    Desulfurization of waste gases of the incinerator after petroleum refining was developed. Mixing of wastes with lime (10% of additive of total volume of waste) was proved before introduction into incinerator. Concentrations of CO, CO 2 , O 2 , NO 2 , SO 2 and temperature of combustion products were measured by automatic analyser

  9. Muonium formation in noble gases and noble gas mixtures

    Stambaugh, R.D.; Casperson, D.E.; Crane, T.W.; Hughes, V.W.; Kaspar, H.F.; Souder, P.; Thompson, P.A.; Orth, H.; zu Putlitz, G.; Denison, A.B.

    1974-01-01

    An experiment is reported to study the behavior of positive muons stopped in He, Ne, and Xe in order to provide a more complete understanding of muonium formation in the noble gases. Free muon and muonium precession are plotted. (U.S.)

  10. Optical monitoring of gases with cholesteric liquid crystals

    Han, Y.; Pacheco Morillo, K.B.; Bastiaansen, C.W.M.; Broer, D.J.; Sijbesma, R.P.

    2010-01-01

    A new approach to optical monitors for gases is introduced using cholesteric liquid crystals doped with reactive chiral compounds. The approach is based on cholesteric pitch length changes caused by a change in helical twisting power (HTP) of the chiral dopants upon reaction with the analyte. The

  11. Development of proportional counters using photosensitive gases and liquids

    Anderson, D.F.

    1984-10-01

    An introduction to the history and to the principle of operation of wire chambers using photosensitive gases and liquids is presented. Their use as light sensors coupled to Gas Scintillation Proportional Counters and BaF 2 , as well as their use in Cherenkov Ring imaging, is discussed in some detail. 42 references, 21 figures

  12. Noble Gases in the Hamlet Meteorite (LL4)

    Amari, S.; Sabe, Y.; Shiraishi, T.; Matsuda, J.

    2014-09-01

    We analyzed noble gases in a bulk sample and an HF-HCl residue of Hamlet (LL4). The Xe composition of the residue shows that no diamond is contained in the residue. The 20Ne/22Ne ratio of Hamlet Ne-Q has been determined to be 11.0 ± 0.5.

  13. A retrospective analysis of blood gases with two different insulin ...

    A retrospective analysis of blood gases with two different insulin infusion protocols in patients undergoing cardiovascular surgery. ... In this study, we aimed to look into the effect of glycemic control on arterial blood gas parameters, serum electrolytes, and hemoglobin (Hb). Materials and Methods: We collected data from ...

  14. Discovery Mondays - Gases: more to them than meets the eye!

    2005-01-01

    We generally tend to think that if a space is empty there is nothing in it. However, did you know that at the Earth's surface there are 25 million million million (1018) molecules of gas in every cubic centimetre of atmosphere? CERN uses a lot of gas to operate its experiments. Above a few of the helium tanks for the LHC. At CERN, gases are put to multiple uses. Gases are used to protect, to cool and also to detect particles... Suffice to say that gases play a vital role at CERN. Why does the air supply to the accelerator tunnel 100 metres below the surface have to be treated and what treatment techniques are used? What are the different types of apparatus that enable you to breathe in confined spaces? How are gases used as a detection medium in the particle detectors? What is Brownian motion? To find out the answers, step on the gas to join us for the next Discovery Monday! This Discovery Monday will be taking place as part of the World Year of Physics, as its theme is closely associated with one of the ...

  15. Spin-charge separation in ultra-cold quantum gases

    Recati, A.; Fedichev, P. O.; Zwerger, W.; Zoller, P.

    2002-01-01

    We investigate the physical properties of quasi-1D quantum gases of fermion atoms confined in harmonic traps. Using the fact that for a homogeneous gas, the low energy properties are exactly described by a Luttinger model, we analyze the nature and manifestations of the spin-charge separation. Finally we discuss the necessary physical conditions and experimental limitations confronting possible experimental implementations.

  16. Normal-superfluid interface for polarized fermion gases

    Van Schaeybroeck, B.; Lazarides, A.

    2009-01-01

    Recent experiments on imbalanced fermion gases have proved the existence of a sharp interface between a superfluid and a normal phase. We show that, at the lowest experimental temperatures, a temperature difference between normal N and superfluid SF phases can appear as a consequence of the blocking

  17. 40 CFR 86.214-94 - Analytical gases.

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Analytical gases. 86.214-94 Section 86.214-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... Later Model Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium-Duty...

  18. Thermal diffusion baro-effect in cluster gases

    Kurlapov, L.M.; Segeda, T.A.

    2003-01-01

    Thermal diffusion baro-effect as a difference of pressure under which action in the established process in the close device the particles flow of an irreversible nature is counterbalanced by current of gas is considered. For not ideal gases the settlement formula is received, in which no ideality is taken into account through the compressibility factor and also for cluster mixture. (author)

  19. Pure Gauge theory in crystal lattice and Coulomb gases

    Marchetti, D.H.U.

    1985-01-01

    A method for the construction of classical gases, starting from a pure gauge theory, is described. The method is applied to the U(1) gauge theory in two spatial dimensions. For this model it's seen the vaccua appearing as a consequence of the quantization ambiguity. The connection between the vaccua and the confinement is discussed. (Author) [pt

  20. An overview on non-CO2 greenhouse gases

    Pulles, T.; Amstel, van A.R.

    2010-01-01

    Non-CO2 greenhouse gases, included in the Kyoto Protocol, are methane (CH4), nitrous oxide (N2O), hexafluorocarbons (HFC), perfluorinated compounds (PFC) and sulphur hexafluoride (SF6). Together they account for about 25% of the present global greenhouse gas emissions. Reductions in emissions of

  1. The Common Agricultural Policy and the Greenhouse Gases Emissions

    BRITO SOARES, F.; Ronco, R.

    2005-01-01

    The evolution of greenhouse gases emissions in the EU-15 countries is accessed. While the absolute level of emissions turns out to be declining in the last thirty years in EU-15 Member States, emissions per output tend to rise. A relationship between the adoption of the Common Agricultural policy and the emissions level can be detected for Spain, Austria, Finland and Sweden.

  2. Comparison of natural gases accumulated in Oligocene strata with hydrous pyrolysis gases from Menilite Shales of the Polish Outer Carpathians

    Kotarba, M.J.; Curtis, John B.; Lewan, M.D.

    2009-01-01

    This study examined the molecular and isotopic compositions of gases generated from different kerogen types (i.e., Types I/II, II, IIS and III) in Menilite Shales by sequential hydrous pyrolysis experiments. The experiments were designed to simulate gas generation from source rocks at pre-oil-cracking thermal maturities. Initially, rock samples were heated in the presence of liquid water at 330 ??C for 72 h to simulate early gas generation dominated by the overall reaction of kerogen decomposition to bitumen. Generated gas and oil were quantitatively collected at the completion of the experiments and the reactor with its rock and water was resealed and heated at 355 ??C for 72 h. This condition simulates late petroleum generation in which the dominant overall reaction is bitumen decomposition to oil. This final heating equates to a cumulative thermal maturity of 1.6% Rr, which represents pre-oil-cracking conditions. In addition to the generated gases from these two experiments being characterized individually, they are also summed to characterize a cumulative gas product. These results are compared with natural gases produced from sandstone reservoirs within or directly overlying the Menilite Shales. The experimentally generated gases show no molecular compositions that are distinct for the different kerogen types, but on a total organic carbon (TOC) basis, oil prone kerogens (i.e., Types I/II, II and IIS) generate more hydrocarbon gas than gas prone Type III kerogen. Although the proportionality of methane to ethane in the experimental gases is lower than that observed in the natural gases, the proportionality of ethane to propane and i-butane to n-butane are similar to those observed for the natural gases. ??13C values of the experimentally generated methane, ethane and propane show distinctions among the kerogen types. This distinction is related to the ??13C of the original kerogen, with 13C enriched kerogen generating more 13C enriched hydrocarbon gases than

  3. Low carbon fuel and chemical production from waste gases

    Simpson, S.; Liew, F.M.; Daniell, J.; Koepke, M. [LanzaTech, Ltd., Auckland (New Zealand)

    2012-07-01

    LanzaTech has developed a gas fermentation platform for the production of alter native transport fuels and commodity chemicals from carbon monoxide, hydrogen and carbon dioxide containing gases. LanzaTech technology uses these gases in place of sugars as the carbon and energy source for fermentation thereby allowing a broad spectrum of resources to be considered as an input for product synthesis. At the core of the Lanzatech process is a proprietary microbe capable of using gases as the only carbon and energy input for product synthesis. To harness this capability for the manufacture of a diverse range of commercially valuable products, the company has developed a robust synthetic biology platform to enable a variety of novel molecules to be synthesised via gas fermentation. LanzaTech initially focused on the fermentation of industrial waste gases for fuel ethanol production. The company has been operating pilot plant that uses direct feeds of steel making off gas for ethanol production for over 24 months. This platform technology has been further successfully demonstrated using a broad range of gas inputs including gasified biomass and reformed natural gas. LanzaTech has developed the fermentation, engineering and control systems necessary to efficiently convert gases to valuable products. A precommercial demonstration scale unit processing steel mill waste gases was commissioned in China during the 2{sup nd} quarter of 2012. Subsequent scale-up of this facility is projected for the 2013 and will represent the first world scale non-food based low carbon ethanol project. More recently LanzaTech has developed proprietary microbial catalysts capable of converting carbon dioxide in the presence of hydrogen directly to value added chemicals, where-in CO{sub 2} is the sole source of carbon for product synthesis. Integrating the LanzaTech technology into a number of industrial facilities, such as steel mills, oil refineries and other industries that emit Carbon bearing

  4. Oral pregnancy tumor

    Shailesh M Gondivkar

    2010-01-01

    Full Text Available Pyogenic granuloma is one of the inflammatory hyperplasias seen in the oral cavity. This term is a misnomer because the lesion is unrelated to infection and in reality arises in response to various stimuli such as low-grade local irritation, traumatic injury, or hormonal factors. It predominantly occurs in the second decade of life in young females, possibly because of the vascular effects of female hormones. Clinically, oral pyogenic granuloma is a smooth or lobulated exophytic lesion manifesting as small, red erythematous growth on a pedunculated or sometimes sessile base, which is usually hemorrhagic. Although excisional surgery is the treatment of choice , some other treatment protocols such as the use of Nd:YAG laser, flash lamp pulsed dye laser, cryosurgery, intralesional injection of ethanol or corticosteroids, and sodium tetradecyl sulfate sclerotherapy have been proposed. We present the case of a 25-year-old pregnant woman with large oral pyogenic granuloma.

  5. Impact Delivery of Reduced Greenhouse Gases on Early Mars

    Haberle, R. M.; Zahnle, K. J.; Barlow, N. G.

    2017-12-01

    Reducing greenhouse gases are the latest trend in finding solutions to the early Mars climate dilemma. In thick CO2 atmospheres with modest concentrations of H2 and/or CH4, collision induced absorptions can reduce the outgoing long wave radiation enough to provide a significant greenhouse effect. To raise surface temperatures significantly by this process, surface pressures must be at least 500 mb and H2 and/or CH4 concentrations must be at or above the several percent level. Volcanism, serpentinization, and impacts are possible sources for reduced gases. Here we investigate the delivery of such gases by impact degassing from comets and asteroids. We use a time-marching stochastic impactor model that reproduces the observed crater size frequency distribution of Noachian surfaces. Following each impact, reduced gases are added to the atmosphere from a production function based on gas equilibrium calculations for several classes of meteorites and comets at typical post-impact temperatures. Escape and photochemistry then remove the reduced greenhouse gases continuously in time throughout each simulation. We then conduct an ensemble of simulations with this simple model varying the surface pressure, impact history, reduced gas production and escape functions, and mix of impactor types, to determine if this could be a potentially important part of the early Mars story. Our goal is to determine the duration of impact events that elevate reduced gas concentrations to significant levels and the total time of such events throughout the Noachian. Our initial simulations indicate that large impactors can raise H2 concentrations above the 10% level - a level high enough for a very strong greenhouse effect in a 1 bar CO2 atmosphere - for millions of years, and that the total time spent at or above that level can be in the 10's of millions of years range. These are interesting results that we plan to explore more thoroughly for the meeting.

  6. Development of electrochemical sensor for the determination of toxic gases

    Ahmed, R.

    1997-01-01

    Monitoring release of flue and toxic gases and vapours of volatile organic toxic substances into the atmosphere is one of the most important problems in environmental pollution control studies particularly in industrial installations in order to avoid poisoning and other health hazards. In industrial areas continuous monitoring of toxic gases and vapours is required for the safety of workers and for this purpose different types of sensors and available such as thermal sensors mass sensors, biosensors, optical sensors and electrochemical sensors. Among all of these sensors electrochemical sensors are most cost-effective, accurate and very good for continuous monitoring. They can be categorized into potentiometric, conductometric, amperometric and voltammetric sensors. Applications of different types of electrochemical sensors are briefly reviewed. Development of polymer membrane and conducting polymers are most important for fabrication of electrochemical sensors, which can analyse up to twenty two gases and vapours simultaneously. Some of the commercially used electrochemical sensors are described. For the determination of hydrogen sulfide an electrochemical sensor was developed. Teflon based conduction polymer membrane was treated with some electrolytes and then silver metal was deposited on one side of the membrane. Metal part side was exposed to gases and the other side was deposited on one side of the membrane metal part side was exposed to gasses and the other side was connected with two electrodes including reference and counter electrodes, whereas metal part acted as working electrode. This system can also me used for the analysis of their gases like SO/sub 2/ etc; because they react at different potentials with the metal to generate the signals. (author)

  7. Shared Oral Care

    Hede, Børge; Elmelund Poulsen,, Johan; Christophersen, Rasmus

    2014-01-01

    Shared Oral Care - Forebyggelse af orale sygdomme på plejecentre Introduktion og formål: Mangelfuld mundhygiejne hos plejekrævende ældre er et alment og veldokumenteret sundhedsproblem, der kan føre til massiv udvikling af tandsygdomme, og som yderligere kan være medvirkende årsag til alvorlige...... ressourceanvendelse er muligt at skabe en betydeligt forbedret mundhygiejne hos plejekrævende ældre Key words: Geriatric dentistry, nursing home, community health services, prevention, situated learning...

  8. Oral lichen planus

    Rasool, S.; Katpar, S.; Ali, A.

    2007-01-01

    Lichen planus is a mucocutaneous dermatological disorder, with intraoral manifestation. Skin lesions prevail with oral mucosal lesions. Prevalence of lichen planus, as an oral pre-malignant lesion, is 1-2 % population. Lateral border, dorsal tongue, gingiva, hard palate and vermilion border are common sites and lesions appear as reticular, plaque-like and papular intraoral types. Skin presents with pururitic, polygonal papules. Atrophic and erosive are the known intraoral pre-malignant types. A case report is presented, which responded well to steroid therapy. (author)

  9. Inequalities in oral health and oral health promotion

    Moysés, Samuel Jorge

    2012-01-01

    This article offers a critical review of the problem of inequalities in oral health and discusses strategies for disease prevention and oral health promotion. It shows that oral health is not merely a result of individual biological, psychological, and behavioral factors; rather, it is the sum of collective social conditions created when people interact with the social environment. Oral health status is directly related to socioeconomic position across the socioeconomic gradient in almost all...

  10. Probiotics as oral health biotherapeutics.

    Saha, Shyamali; Tomaro-Duchesneau, Catherine; Tabrizian, Maryam; Prakash, Satya

    2012-09-01

    Oral health is affected by its resident microorganisms. Three prominent oral disorders are dental caries, gingivitis and periodontitis, with the oral microbiota playing a key role in the initiation/progression of all three. Understanding the microbiota and the diseases they may cause is critical to the development of new therapeutics. This review is focused on probiotics for the prevention and/or treatment of oral diseases. This review describes the oral ecosystem and its correlation with oral health/disease. The pathogenesis and current prevention/treatment strategies of periodontal diseases (PD) and dental caries (DC) are depicted. An introduction of probiotics is followed by an analysis of their role in PD and DC, and their potential role(s) in oral health. Finally, a discussion ensues on the future research directions and limitations of probiotics for oral health. An effective oral probiotic formulation should contribute to the prevention/treatment of microbial diseases of the oral cavity. Understanding the oral microbiota's role in oral disease is important for the development of a therapeutic to prevent/treat dental diseases. However, investigations into clinical efficacy, delivery/dose optimization, mechanism(s) of action and other related parameters are yet to be fully explored. Keeping this in mind, investigations into oral probiotic therapies are proving promising.

  11. Emissions, activity data, and emission factors of fluorinated greenhouse gases (F-Gases) in Germany 1995-2002

    Schwarz, Winfried [Oeko-Recherche, Buero fuer Umweltforschung und -beratung GmbH, Frankfurt am Main (Germany)

    2005-06-15

    Before the 1997 Kyoto Protocol on Climate Protection, the fluorinated greenhouse gases HFCs, PFCs, and SF6 (F-gases) aroused little public attention. Since then, the standards on surveying and reporting on national emissions have been rising constantly. Amongst others, the annual reporting to the UNFCCC secretariat makes detailed declarations on use and emissions of F-gases necessary, which have to be filled in specified formats for submission (Common Reporting Format = CRF). The scientific basis has been set out by the UNFCCC guidelines on reporting, in accordance with the instructions laid down in IPCC good practice guidance. Additionally, in Germany the Centralised System of Emissions (ZSE) shall provide a suitable tool to satisfy any quality needs of both activity data and emission factors. From 1995 onwards, activity data and emissions of each individual application sector shall be presented in a comprehensible and transparent way. Therefore, the way of data collection as well as the estimation methods applied must be well documented. Moreover, data has to be prepared for appropriate importation into ZSE. It is the objective of this study to provide the transparency demanded within 40 national application sectors of F-gases, for the period between 1995 and 2002. - Firstly, all the activity data as well as the emissions related to them are presented and commented. This applies to manufacturing of products, F-gases banked in operating systems, and decommissioning. - Secondly, the methodologies applied to calculate the emissions are described and all sources of information are revealed, e.g. literature, names of experts from the manufacturing industry, users, trade, and academia. - Thirdly, reliability and safety of data are discussed. - Fourthly, possible deviations from the IPCC default values are stated and given reasons for. Wherever this intensive reviewing of 40 sectors through eight years of reporting uncovers gaps or inconsistencies in previous reports

  12. Oral hygiene practices and risk of oral leukoplakia | Macigo | East ...

    Objective: To determine the influence of oral hygiene habits and practices on the risk of developing oral leukoplakia. Design: Case control study. Setting: Githongo sublocation in Meru District. Subjects: Eighty five cases and 141 controls identified in a house-to-house screening. Results: The relative risk (RR) of oral ...

  13. Metabolomic Studies of Oral Biofilm, Oral Cancer, and Beyond

    Jumpei Washio

    2016-06-01

    Full Text Available Oral diseases are known to be closely associated with oral biofilm metabolism, while cancer tissue is reported to possess specific metabolism such as the ‘Warburg effect’. Metabolomics might be a useful method for clarifying the whole metabolic systems that operate in oral biofilm and oral cancer, however, technical limitations have hampered such research. Fortunately, metabolomics techniques have developed rapidly in the past decade, which has helped to solve these difficulties. In vivo metabolomic analyses of the oral biofilm have produced various findings. Some of these findings agreed with the in vitro results obtained in conventional metabolic studies using representative oral bacteria, while others differed markedly from them. Metabolomic analyses of oral cancer tissue not only revealed differences between metabolomic profiles of cancer and normal tissue, but have also suggested a specific metabolic system operates in oral cancer tissue. Saliva contains a variety of metabolites, some of which might be associated with oral or systemic disease; therefore, metabolomics analysis of saliva could be useful for identifying disease-specific biomarkers. Metabolomic analyses of the oral biofilm, oral cancer, and saliva could contribute to the development of accurate diagnostic, techniques, safe and effective treatments, and preventive strategies for oral and systemic diseases.

  14. Oral Hygiene and Oral Flora Evaluation in Psychiatric Patients in ...

    Conclusions: The oral hygiene of most patients was insufficient. The presence of Gram‑negative Bacilli growth in the oral flora can be explained by poor hand hygiene. These findings suggest that it is useful to educate individuals about oral hygiene and hand hygiene and to inform the staff and families about this issue.

  15. The New Orality: Oral Characteristics of Computer-Mediated Communication.

    Ferris, Sharmila Pixy; Montgomery, Maureen

    1996-01-01

    Considers the characteristics of orality and literacy developed in the work of scholars such as Walter Ong to consider computer-mediated communication (CMC) as the potential site of a "new orality" which is neither purely oral or literate. Notes that the medium of CMC is writing, which has traditionally represented the…

  16. Metabolomic Studies of Oral Biofilm, Oral Cancer, and Beyond.

    Washio, Jumpei; Takahashi, Nobuhiro

    2016-06-02

    Oral diseases are known to be closely associated with oral biofilm metabolism, while cancer tissue is reported to possess specific metabolism such as the 'Warburg effect'. Metabolomics might be a useful method for clarifying the whole metabolic systems that operate in oral biofilm and oral cancer, however, technical limitations have hampered such research. Fortunately, metabolomics techniques have developed rapidly in the past decade, which has helped to solve these difficulties. In vivo metabolomic analyses of the oral biofilm have produced various findings. Some of these findings agreed with the in vitro results obtained in conventional metabolic studies using representative oral bacteria, while others differed markedly from them. Metabolomic analyses of oral cancer tissue not only revealed differences between metabolomic profiles of cancer and normal tissue, but have also suggested a specific metabolic system operates in oral cancer tissue. Saliva contains a variety of metabolites, some of which might be associated with oral or systemic disease; therefore, metabolomics analysis of saliva could be useful for identifying disease-specific biomarkers. Metabolomic analyses of the oral biofilm, oral cancer, and saliva could contribute to the development of accurate diagnostic, techniques, safe and effective treatments, and preventive strategies for oral and systemic diseases.

  17. Imaging in oral cancers

    Arya, Supreeta; Chaukar, Devendra; Pai, Prathamesh

    2012-01-01

    Oral cavity squamous cell cancers form a significant percentage of the cancers seen in India. While clinical examination allows direct visualization, it cannot evaluate deep extension of disease. Cross-sectional imaging has become the cornerstone in the pretreatment evaluation of these cancers and provides accurate information about the extent and depth of disease that can help decide the appropriate management strategy and indicate prognosis. Early cancers are treated with a single modality, either surgery or radiotherapy while advanced cancers are offered a combination of surgery, radiotherapy and chemotherapy. Imaging can decide resectability, help plan the precise extent of resection, and indicate whether organ conservation therapy should be offered. Quality of life issues necessitate preservation of form and function and pretreatment imaging helps plan appropriate reconstruction and counsel patients regarding lifestyle changes. Oral cavity has several subsites and the focus of the review is squamous cancers of the gingivobuccal region, oral tongue and retromolar trigone as these are most frequently encountered in the subcontinent. References for this review were identified by searching Medline and PubMed databases. Only articles published in English language literature were selected. This review aims to familiarize the radiologist with the relevant anatomy of the oral cavity, discuss the specific issues that influence prognosis and management at the above subsites, the optimal imaging methods, the role of imaging in accurately staging these cancers and in influencing management. A checklist for reporting will emphasize the information to be conveyed by the radiologist

  18. IDEA: Stimulating Oral Production.

    Easley, Jacob J.

    1995-01-01

    Presents daily activities that facilitate complete sentence response, promote oral production, and aid the learning of vocabulary in foreign-language classes. Because speech is the primary form of communication in the foreign-language classroom, it is important to stimulate students to converse as soon as possible. (Author/CK)

  19. Fluoride and Oral Health

    O'Mullane, D M; Baez, R J; Jones, S

    2016-01-01

    and strategies is noteworthy. This updated version of ‘Fluoride and Oral Health’ has adopted an evidence-based approach to its commentary on the different fl uoride vehicles and strategies and also to its recommendations. In this regard, full account is taken of the many recent systematic reviews published...

  20. Oral Health and Women

    2009-05-12

    This women's health podcast focuses on the importance of maintaining good oral health during pregnancy.  Created: 5/12/2009 by Office of Women’s Health (OWH) and National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 5/12/2009.

  1. History of oral contraception.

    Dhont, Marc

    2010-12-01

    On the 50th birthday of the pill, it is appropriate to recall the milestones which have led to its development and evolution during the last five decades. The main contraceptive effect of the pill being inhibition of ovulation, it may be called a small miracle that this drug was developed long before the complex regulation of ovulation and the menstrual cycle was elucidated. Another stumbling block on its way was the hostile climate with regard to contraception that prevailed at the time. Animal experiments on the effect of sex steroids on ovulation, and the synthesis of sex steroids and orally active analogues were the necessary preliminaries. We owe the development of oral contraceptives to a handful of persons: two determined feminists, Margaret Sanger and Katherine McCormick; a biologist, Gregory Pincus; and a gynaecologist, John Rock. Soon after the introduction of the first pills, some nasty and life-threatening side effects emerged, which were due to the high doses of sex steroids. This led to the development of new preparations with reduced oestrogen content, progestins with more specific action, and alternative administration routes. Almost every decade we have witnessed a breakthrough in oral contraception. Social and moral objections to birth control have gradually disappeared and, notwithstanding some pill scares, oral contraceptives are now one of the most used methods of contraception. Finally, all's well that ends well: recent reports have substantiated the multiple noncontraceptive health benefits paving the way for a bright future for this 50-year-old product.

  2. Oral Lichen Planus.

    Ion, Daniela I; Setterfield, Jane F

    2016-02-01

    Lichen planus (LP) is a relatively common autoimmune T-cell-mediated disease of unknown aetiology affecting the mucous membranes, skin and nails. Its prevalence varies between 0.5 and 2.2% of the population in epidemiological studies with a peak incidence in the 30-60 years range and with a female predominance of 2:1. Mucosal lichen planus tends to follow a chronic course with acute exacerbations. Spontaneous remission of oral lichen planus (OLP) is uncommon, and indeed mucosal LP may become worse with time. In contrast, cutaneous lichen planus may follow a milder clinical course though some variants may be severe such as those affecting the palms and soles and the scalp and the genital tract in females (vulvovaginal gingival LP) where scarring leads to significant complications. It is important to identify those cases that may be drug induced or be associated with a contact allergic or irritant reaction (lichenoid reaction) or the rarer oral presentation of discoid lupus erythematosus. There is a very small risk of malignancy (approximately 1:200 patients/year) associated with oral lichen planus; thus patients should be informed that long term monitoring via their general dental practitioner is appropriate. This review will focus on the clinical presentation and management of oral lichen planus.

  3. Oral lichen planus

    Šehalić Meliha

    2014-01-01

    Full Text Available 29 - year Lichen planus is a chronic, inflammatory, autoimmune skin disease, that is often manifested, except on the skin, in the oral cavity in a variety of clinical forms. The prevalence of the disease in the general population is about 1-2%. Etiopathogenesis is not still well understood. Histopathology, in addition to the basic methods, anamnesis and physical examination, is vital for proper diagnosis of oral lichen planus (OLP. Very diverse and loaded histological findings are common for all forms of oral lichen planus. We reported the case of oral lichen planus in a 49 years old male patient, who presented to the Dentistry clinic of Medical faculty of Priština with burning and itching symptoms and changes in the buccal mucosa. Histopathological analysis of biopsy tissue conformed clinical diagnosis of lichen planus. Due to the possibility for malignant transformation of lesions, the long-term follow-up of patients with this disease is of great importance.

  4. Antibiotics and oral contraceptives.

    DeRossi, Scott S; Hersh, Elliot V

    2002-10-01

    With the exception of rifampin-like drugs, there is a lack of scientific evidence supporting the ability of commonly prescribed antibiotics, including all those routinely employed in outpatient dentistry, to either reduce blood levels and/or the effectiveness of oral contraceptives. To date, all clinical trials studying the effects of concomitant antibiotic therapy (with the exception of rifampin and rifabutin) have failed to demonstrate an interaction. Like all drugs, oral contraceptives are not 100% effective with the failure rate in the typical United States population reported to be as high as 3%. It is thus possible that the case reports of unintended pregnancies during antibiotic therapy may simply represent the normal failure rate of these drugs. Considering that both drug classes are prescribed frequently to women of childbearing potential, one would expect a much higher rate of oral contraceptive failure in this group of patients if a true drug:drug interaction existed. On the other hand, if the interaction does exist but is a relatively rare event, occurring in, say, 1 in 5000 women, clinical studies such as those described in this article would not detect the interaction. The pharmacokinetic studies of simultaneous antibiotic and oral contraceptive ingestion, and the retrospective studies of pregnancy rates among oral contraceptive users exposed to antibiotics, all suffer from one potential common weakness, i.e., their relatively small sample size. Sample sizes in the pharmacokinetic trials ranged from 7 to 24 participants, whereas the largest retrospective study of pregnancy rates still evaluated less than 800 total contraceptive users. Still, the incidence of such a rare interaction would not differ from the accepted normal failure rate of oral contraceptive therapy. The medico-legal ramifications of what looks like at best a rare interaction remains somewhat "murky." On one hand, we have medico-legal experts advising the profession to exercise caution

  5. Head, Neck, and Oral Cancer

    Full Text Available ... Extensive education and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral ... Extensive education and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral ...

  6. Head, Neck, and Oral Cancer

    Full Text Available ... Contact Find a Surgeon What We Do Anesthesia Anesthesia Oral and maxillofacial surgeons are extensively trained to ... and Facial Pain Wisdom Teeth Management Procedures Anesthesia Anesthesia Oral and maxillofacial surgeons are extensively trained to ...

  7. Head, Neck, and Oral Cancer

    Full Text Available ... mouth and gums to improve function, appearance and oral health. Click here to find out more. Facial Cosmetic ... mouth and gums to improve function, appearance and oral health. Click here to find out more. Facial Cosmetic ...

  8. Head, Neck, and Oral Cancer

    Full Text Available ... Oral and maxillofacial surgeons. The experts in face, mouth and jaw surgery.™ What We Do Who We ... surgically treat the soft tissues of the face, mouth and gums to improve function, appearance and oral ...

  9. Head, Neck, and Oral Cancer

    Full Text Available ... and Neck Pathology Close to 49,750 Americans will be diagnosed with oral or pharyngeal cancer this ... and Neck Pathology Close to 49,750 Americans will be diagnosed with oral or pharyngeal cancer this ...

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    Full Text Available ... tissues of the face, mouth and gums to improve function, appearance and oral health. Click here to ... tissues of the face, mouth and gums to improve function, appearance and oral health. Click here to ...

  11. Head, Neck, and Oral Cancer

    Full Text Available ... and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and maxillofacial ... and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and maxillofacial ...

  12. Head, Neck, and Oral Cancer

    Full Text Available ... and gums to improve function, appearance and oral health. Click here to find out more. Facial Cosmetic ... and gums to improve function, appearance and oral health. Click here to find out more. Facial Cosmetic ...

  13. Head, Neck, and Oral Cancer

    Full Text Available ... in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and maxillofacial surgeon to ... in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and maxillofacial surgeon to ...

  14. Head, Neck, and Oral Cancer

    Full Text Available ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

  15. Head, Neck, and Oral Cancer

    Full Text Available ... for further information Your oral and maxillofacial surgeon (OMS) is the expert for diagnosing and surgically treating ... late in its development. Your family dentist or OMS is in the best position to detect oral ...

  16. Head, Neck, and Oral Cancer

    Full Text Available ... and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed with ... and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed with ...

  17. Head, Neck, and Oral Cancer

    Full Text Available ... education and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and ... education and training in surgical procedures involving skin, muscle, bone and cartilage finely attune the oral and ...

  18. 75 FR 17331 - Public Hearings for the Mandatory Reporting Rule for Greenhouse Gases

    2010-04-06

    ... for Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION: Announcement of public... mandatory reporting of greenhouse gases, which will be published separately in the Federal Register. These proposed rules would [[Page 17332

  19. An introduction to the Boltzmann equation and transport processes in gases

    Kremer, Gilberto M; Colton, David

    2010-01-01

    This book covers classical kinetic theory of gases, presenting basic principles in a self-contained framework and from a more rigorous approach based on the Boltzmann equation. Uses methods in kinetic theory for determining the transport coefficients of gases.

  20. Method and apparatus for removing radioactive gases from a nuclear reactor

    Frumerman, R.; Brown, W.W.

    1975-01-01

    A description is given of a method for removing radioactive gases from a nuclear reactor including the steps of draining coolant from a nuclear reactor to a level just below the coolant inlet and outlet nozzles to form a vapor space and then charging the space with an inert gas, circulating coolant through the reactor to assist the release of radioactive gases from the coolant into the vapor space, withdrawing the radioactive gases from the vapor space by a vacuum pump which then condenses and separates water from gases carried forward by the vacuum pump, discharging the water to a storage tank and supplying the separated gases to a gas compressor which pumps the gases to gas decay tanks. After the gases in the decay tanks lose their radioactive characteristics, the gases may be discharged to the atmosphere or returned to the reactor for further use