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Sample records for highly reactive plasma

  1. Method for generating a highly reactive plasma for exhaust gas after treatment and enhanced catalyst reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

    2000-07-01

    This patent application describes a method and apparatus of exhaust gas remediation that enhance the reactivity of the material catalysts found within catalytic converters of cars, trucks, and power stations.

  2. High density plasma reactive ion etching of Ru thin films using non-corrosive gas mixture

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Su Min; Garay, Adrian Adalberto; Lee, Wan In; Chung, Chee Won, E-mail: cwchung@inha.ac.kr

    2015-07-31

    Inductively coupled plasma reactive ion etching (ICPRIE) of Ru thin films patterned with TiN hard masks was investigated using a CH{sub 3}OH/Ar gas mixture. As the CH{sub 3}OH concentration in CH{sub 3}OH/Ar increased, the etch rates of Ru thin films and TiN hard masks decreased. However, the etch selectivity of Ru films on TiN hard masks increased and the etch slope of Ru film improved at 25% CH{sub 3}OH/Ar. With increasing ICP radiofrequency power and direct current bias voltage and decreasing process pressure, the etch rates of Ru films increased, and the etch profiles were enhanced without redeposition on the sidewall. Optical emission spectroscopy and X-ray photoelectron spectroscopy were employed to analyze the plasma and surface chemistry. Based on these results, Ru thin films were oxidized to RuO{sub 2} and RuO{sub 3} compounds that were removed by sputtering of ions and the etching of Ru thin films followed a physical sputtering with the assistance of chemical reaction. - Highlights: • Etching of Ru films in CH{sub 3}OH/Ar was investigated. • High selectivity and etch profile with high degree of anisotropy were obtained. • XPS analysis was examined to identify the etch chemistry. • During etching Ru was oxidized to RuO{sub 2} and RuO{sub 3} can be easily sputtered off.

  3. Formation of High Temperature Compounds in W-C-B System by Reactive Spark Plasma Sintering

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    Janis Grabis

    2015-09-01

    Full Text Available The formation of high temperature composites in W-C-Bsystem from fine-grained powders in dependence on the ratio of components byusing reactive spark plasma sintering was studied. The mixture of W2Cand C nanoparticles was used as tungsten and carbon precursors. The W2Cand carbon mixture with different ratio of components was prepared by reductionof WO3 in presence of CH4 in nitrogen inductively coupledplasma. The specific surface area of the mixture was in the range of 36–42 m2/gin dependence on the content of carbon. The W2C and carbon particleswere mixed mechanically with amorphous boron and densified using the sparkplasma sintering technique at 1500–1700 oC and pressure of 30 MPafor 4 minutes. The sintered bodies contained WB2 and B4Cphases. The ratio of phase depends on the content of the components in the rawmixture.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7352

  4. Enhanced biocompatibility of TiO2 surfaces by highly reactive plasma

    Science.gov (United States)

    Junkar, Ita; Kulkarni, Mukta; Drašler, Barbara; Rugelj, Neža; Recek, Nina; Drobne, Damjana; Kovač, Janez; Humpolicek, Petr; Iglič, Aleš; Mozetič, Miran

    2016-06-01

    In the present study the biological response to various nanotopographic features after gaseous plasma treatment were studied. The usefulness of nanostructured surfaces for implantable materials has already been acknowledged, while less is known on the combined effect of nanostructured plasma modified surfaces. In the present work the influence of oxygen plasma treatment on nanostructured titanium oxide (TiO2) surfaces was studied. Characterization of the TiO2 surface chemical composition and morphological features was analyzed after plasma modification by x-ray photoelectron spectroscopy and by scanning electron microscopy while surface wettability was studied with measuring the water contact angle. Cell adhesion and morphology was assessed from images taken with scanning electron microscopy, whereas cell viability was measured with a calorimetric assay. The obtained results showed that oxygen plasma treatment of TiO2 nanotube surfaces significantly influences the adhesion and morphology of osteoblast-like cells in comparison to untreated nanostructured surfaces. Marked changes in surface composition of plasma treated surfaces were observed, as plasma treatment removed hydrocarbon contamination and removed fluorine impurities, which were present due to the electrochemical anodization process. However no differences in wettability of untreated and plasma treated surfaces were noticed. Treatment with oxygen plasma stimulated osteoblast-like cell adhesion and spreading on the nanostructured surface, suggesting the possible use of oxygen plasma surface treatment to enhance osteoblast-like cell response.

  5. Comparison of Reactive and Non-Reactive Spark Plasma Sintering Routes for the Fabrication of Monolithic and Composite Ultra High Temperature Ceramics (UHTC Materials

    Directory of Open Access Journals (Sweden)

    Roberto Orrù

    2013-04-01

    Full Text Available A wider utilization of ultra high temperature ceramics (UHTC materials strongly depends on the availability of efficient techniques for their fabrication as dense bodies. Based on recent results reported in the literature, it is possible to state that Spark Plasma Sintering (SPS technology offers a useful contribution in this direction. Along these lines, the use of two different SPS-based processing routes for the preparation of massive UHTCs is examined in this work. One method, the so-called reactive SPS (R-SPS, consists of the synthesis and densification of the material in a single step. Alternatively, the ceramic powders are first synthesized by Self-propagating High-temperature Synthesis (SHS and then sintered by SPS. The obtained results evidenced that R-SPS method is preferable for the preparation of dense monolithic products, while the sintering of SHS powders requires relatively milder conditions when considering binary composites. The different kinetic mechanisms involved during R-SPS of the monolithic and composite systems, i.e., combustion-like or gradual solid-diffusion, respectively, provides a possible explanation. An important role is also played by the SHS process, particularly for the preparation of composite powders, since stronger interfaces are established between the ceramic constituents formed in situ, thus favoring diffusion processes during the subsequent SPS step.

  6. Application of non-thermal plasma reactor for degradation and detoxification of high concentrations of dye Reactive Black 5 in water

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    Dojčinović Biljana P.

    2016-01-01

    Full Text Available Degradation and detoxification efficiency of high concentrations of commercially available reactive textile dye Reactive Black 5 solution (40, 80, 200, 500, 1000 mg L-1, were studied. Advanced oxidation processes in water falling film based dielectric barrier discharge as a non-thermal plasma reactor were used. For the first time, this reactor was used for the treatment of high concentrations of organic pollutants such as reactive textile dye Reactive Black 5 in water. Solution of the dye is treated by plasma as thin water solution film that is constantly regenerated. Basically, the reactor works as a continuous flow reactor and the electrical discharge itself takes place at the gas-liquid interphase. The dye solution was recirculated through the reactor with an applied energy density of 0-374 kJ L-1. Decolorization efficiency (% was monitored by UV-VIS spectrophotometric technique. Samples were taken after every recirculation (~ 22 kJ L-1 and decolorization percent was measured after 5 min and 24 h of plasma treatment. The efficiency of degradation (i.e. mineralization and possible degradation products were also tracked by determination of the chemical oxygen demand (COD and by ion chromatography (IC. Initial toxicity and toxicity of solutions after the treatment were studied with Artemia salina test organisms. Efficiency of decolorization decreased with the increase of the dye concentration. Complete decolorization, high mineralization and non-toxicity of the solution (<10 % were acomplished after plasma treatment using energy density of 242 kJ L-1, while the initial concentrations of Reactive Black 5 were 40 and 80 mg L-1. [Projekat Ministarstva nauke Republike Srbije, br. 172030 i br. 171034

  7. High temperature reactive ion etching of iridium thin films with aluminum mask in CF4/O2/Ar plasma

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    Chia-Pin Yeh

    2016-08-01

    Full Text Available Reactive ion etching (RIE technology for iridium with CF4/O2/Ar gas mixtures and aluminum mask at high temperatures up to 350 °C was developed. The influence of various process parameters such as gas mixing ratio and substrate temperature on the etch rate was studied in order to find optimal process conditions. The surface of the samples after etching was found to be clean under SEM inspection. It was also shown that the etch rate of iridium could be enhanced at higher process temperature and, at the same time, very high etching selectivity between aluminum etching mask and iridium could be achieved.

  8. Synthesis of functional nanocrystallites through reactive thermal plasma processing

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    Takamasa Ishigaki and Ji-Guang Li

    2007-01-01

    Full Text Available A method of synthesizing functional nanostructured powders through reactive thermal plasma processing has been developed. The synthesis of nanosized titanium oxide powders was performed by the oxidation of solid and liquid precursors. Quench gases, either injected from the shoulder of the reactor or injected counter to the plasma plume from the bottom of the reactor, were used to vary the quench rate, and therefore the particle size, of the resultant powders. The experimental results are well supported by numerical analysis on the effects of the quench gas on the flow pattern and temperature field of the thermal plasma as well as on the trajectory and temperature history of the particles. The plasma-synthesized TiO2 nanoparticles showed phase preferences different from those synthesized by conventional wet-chemical processes. Nanosized particles of high crystallinity and nonequilibrium chemical composition were formed in one step via reactive thermal plasma processing.

  9. Reactive plasma synthesis of nanocrystalline ceramic oxides

    Science.gov (United States)

    Sreekumar, K. P.; Vijay, M.; Thiyagarajan, T. K.; Krishnan, K.; Ananthapadmanabhan, P. V.

    2010-02-01

    Reactive plasma synthesis is an attractive route to synthesize nanocrystalline materials. A 40 kW DC non-transferred arc plasma reactor has been designed and developed in our laboratory for synthesis of nanocrystalline materials. The main components of the plasma reactor include a 40 kW DC plasma generator or plasma torch, water-cooled reactor segment, product collection facility, DC power supply, cooling-water system and exhaust gas vent. The system has been used to synthesize nano-crystalline oxides of aluminium, titanium and zirconium. Aluminium metal powder was used as the starting material to synthesize alumina. The hydrides of Ti and Zr were used as the precursor for synthesis of nanocrystalline titania and zirconia respectively. The precursor powders were injected into the thermal plasma jet and were allowed to react with oxygen injected downstream the jet. The precursor powder particles were oxidized 'in-flight' to form nano-sized powder of the respective metal, which deposited on the walls of the reactor and collector assembly. Various analytical tools were used to characterized the products.

  10. Single-step, rapid low-temperature synthesis of Si quantum dots embedded in an amorphous SiC matrix in high-density reactive plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Qijin [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, PO Box 218, Lindfield, NSW 2070 (Australia); Xu Shuyan [Plasma Sources and Applications Centre, NIE, Nanyang Technological University, 1 Nanyang Walk 637616 (Singapore); Ostrikov, Kostya, E-mail: Kostya.Ostrikov@csiro.au [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, PO Box 218, Lindfield, NSW 2070 (Australia) and School of Physics, University of Sydney, Sydney NSW 2006 (Australia)

    2010-01-15

    A simple, effective and innovative approach based on low-pressure, thermally nonequilibrium, high-density inductively coupled plasmas is proposed to rapidly synthesize Si quantum dots (QDs) embedded in an amorphous SiC (a-SiC) matrix at a low substrate temperature and without any commonly used hydrogen dilution. The experimental results clearly demonstrate that uniform crystalline Si QDs with a size of 3-4 nm embedded in the silicon-rich (carbon content up to 10.7at.%) a-SiC matrix can be formed from the reactive mixture of silane and methane gases, with high growth rates of {approx}1.27-2.34 nm s{sup -1} and at a low substrate temperature of 200 deg. C. The achievement of the high-rate growth of Si QDs embedded in the a-SiC without any commonly used hydrogen dilution is discussed based on the unique properties of the inductively coupled plasma-based process. This work is particularly important for the development of the all-Si tandem cell-based third generation photovoltaic solar cells.

  11. Circulating miR-145 is associated with plasma high-sensitivity C-reactive protein in acute ischemic stroke patients.

    Science.gov (United States)

    Jia, Lihua; Hao, Fang; Wang, Weihua; Qu, Yang

    2015-07-01

    Stroke is a major cerebrovascular disease threatening human health and life with high morbidity, disability and mortality. We aimed to find effective biomarkers for the early diagnosis on stroke. Nine previously reported stroke-associated miRNAs (miR-21, miR-23a, miR-29b, miR-124, miR-145, miR-210, miR-221, miR-223 and miR-483-5p) were measured by quantitative real time-PCR, and plasma high-sensitivity C-reactive protein (hs-CRP) and serum interleukin 6 (IL-6), the pro-inflammation markers in brain injury, were examined by enzyme-linked immunosorbent assay in 146 acute ischemic stroke patients and 96 healthy blood donors. We found that serum miR-145 was significantly increased within 24 h after stroke onset and serum miR-23a and miR-221 were decreased in patients. Moreover, serum miR-145 was strong positively correlated with plasma hs-CRP and moderate positively correlated with serum IL-6. Meanwhile, serum miR-23a and miR-221 were moderate negatively correlated with plasma hs-CRP but not serum IL-6. Importantly, the combination of hs-CRP and serum miR-145 gained a better sensitivity/spectivity for prediction of acute ischemia stroke (area under receiver operating characteristic curve from 0.794 to 0.896). Conclusively, our preliminary findings indicate that serum miR-145 upregulated in acute ischemic stroke might be a new biomarker for acute ischemia stroke evaluation. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Plasma cell treatment device Plasma-on-Chip: Monitoring plasma-generated reactive species in microwells

    Science.gov (United States)

    Oh, Jun-Seok; Kojima, Shinya; Sasaki, Minoru; Hatta, Akimitsu; Kumagai, Shinya

    2017-01-01

    We have developed a plasma cell treatment device called Plasma-on-Chip that enables the real-time monitoring of a single cell culture during plasma treatment. The device consists of three parts: 1) microwells for cell culture, 2) a microplasma device for generating reactive oxygen and nitrogen species (RONS) for use in cell treatment, and 3) through-holes (microchannels) that connect each microwell with the microplasma region for RONS delivery. Here, we analysed the delivery of the RONS to the liquid culture medium stored in the microwells. We developed a simple experimental set-up using a microdevice and applied in situ ultraviolet absorption spectroscopy with high sensitivity for detecting RONS in liquid. The plasma-generated RONS were delivered into the liquid culture medium via the through-holes fabricated into the microdevice. The RONS concentrations were on the order of 10–100 μM depending on the size of the through-holes. In contrast, we found that the amount of dissolved oxygen was almost constant. To investigate the process of RONS generation, we numerically analysed the gas flow in the through-holes. We suggest that the circulating gas flow in the through-holes promotes the interaction between the plasma (ionised gas) and the liquid, resulting in enhanced RONS concentrations. PMID:28176800

  13. INDUCTION PLASMA REACTIVE DEPOSITION OF TUNGSTENCARBIDE FROM TUNGSTEN METAL POWDER

    Institute of Scientific and Technical Information of China (English)

    X.L. Jiang; M.I. Boulos

    2001-01-01

    Experimental results are reported on the primary carburization reaction between the tungsten powder and methane in the induction plasma, and the secondary carburization of the deposit on substrate at high temperature. Optical microscopy and scanning electron microscopy were used to examine the microstructures of starting tungsten powder, carburized powder, and deposit. X-ray diffraction analysis, thermal gravimetric analysis and microhardness measurement were used to characterize the structures and properties of the powder and the deposit. It is found that the primary carburization reaction in the induction plasma starts from the surface of tungsten particles when the particles are melted. Tungsten particles are partially carburized inside the reactive plasma. Complete carburization is achieved through the secondary carburization reaction of the deposit on substrate at high temperature.``

  14. Plasma-generated reactive oxygen species for biomedical applications

    Science.gov (United States)

    Sousa, J. S.; Hammer, M. U.; Winter, J.; Tresp, H.; Duennbier, M.; Iseni, S.; Martin, V.; Puech, V.; Weltmann, K. D.; Reuter, S.

    2012-10-01

    To get a better insight into the effects of reactive oxygen species (ROS) on cellular components, fundamental studies are essential to determine the nature and concentration of plasma-generated ROS, and the chemistry induced in biological liquids by those ROS. In this context, we have measured the absolute density of the main ROS created in three different atmospheric pressure plasma sources: two geometrically distinct RF-driven microplasma jets (μ-APPJ [1] and kinpen [2]), and an array of microcathode sustained discharges [3]. Optical diagnostics of the plasma volumes and effluent regions have been performed: UV absorption for O3 and IR emission for O2(a^1δ) [4]. High concentrations of both ROS have been obtained (10^14--10^17cm-3). The effect of different parameters, such as gas flows and mixtures and power coupled to the plasmas, has been studied. For plasma biomedicine, the determination of the reactive species present in plasma-treated liquids is of great importance. In this work, we focused on the measurement of the concentration of H2O2 and NOX radicals, generated in physiological solutions like NaCl and PBS.[4pt] [1] N. Knake et al., J. Phys. D: App. Phys. 41, 194006 (2008)[0pt] [2] K.D. Weltmann et al., Pure Appl. Chem. 82, 1223 (2010)[0pt] [3] J.S. Sousa et al., Appl. Phys. Lett. 97, 141502 (2010)[0pt] [4] J.S. Sousa et al., Appl. Phys. Lett. 93, 011502 (2008)

  15. High-Sensitivity C-Reactive Protein Complements Plasma Epstein-Barr Virus Deoxyribonucleic Acid Prognostication in Nasopharyngeal Carcinoma: A Large-Scale Retrospective and Prospective Cohort Study

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lin-Quan [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Li, Chao-Feng [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Information Technology, Sun Yat-sen University, Guangzhou (China); Chen, Qiu-Yan; Zhang, Lu [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Lai, Xiao-Ping; He, Yun; Xu, Yun-Xiu-Xiu; Hu, Dong-Peng; Wen, Shi-Hua; Peng, Yu-Tuan [ZhongShan School of Medicine, Sun Yat-sen University, Guangzhou (China); Chen, Wen-Hui [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Liu, Huai; Guo, Shan-Shan; Liu, Li-Ting [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Nasopharyngeal Carcinoma, Sun Yat-sen University, Guangzhou (China); Li, Jing [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Zhang, Jing-Ping [Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University, Guangzhou (China); Department of Clinical Laboratory, Sun Yat-sen University, Guangzhou (China); and others

    2015-02-01

    Purpose: To evaluate the effects of combining the assessment of circulating high-sensitivity C-reactive protein (hs-CRP) with that of Epstein-Barr virus DNA (EBV DNA) in the pretherapy prognostication of nasopharyngeal carcinoma (NPC). Patients and Methods: Three independent cohorts of NPC patients (training set of n=3113, internal validation set of n=1556, and prospective validation set of n=1668) were studied. Determinants of disease-free survival, distant metastasis–free survival, and overall survival were assessed by multivariate analysis. Hazard ratios and survival probabilities of the patient groups, segregated by clinical stage (T1-2N0-1M0, T3-4N0-1M0, T1-2N2-3M0, and T3-4N2-3M0) and EBV DNA load (low or high) alone, and also according to hs-CRP level (low or high), were compared. Results: Elevated hs-CRP and EBV DNA levels were significantly correlated with poor disease-free survival, distant metastasis–free survival, and overall survival in both the training and validation sets. Associations were similar and remained significant after excluding patients with cardiovascular disease, diabetes, and chronic hepatitis B. Patients with advanced-stage disease were segregated by high EBV DNA levels and high hs-CRP level into a poorest-risk group, and participants with either high EBV DNA but low hs-CRP level or high hs-CRP but low EBV DNA values had poorer survival compared with the bottom values for both biomarkers. These findings demonstrate a significant improvement in the prognostic ability of conventional advanced NPC staging. Conclusion: Baseline plasma EBV DNA and serum hs-CRP levels were significantly correlated with survival in NPC patients. The combined interpretation of EBV DNA with hs-CRP levels led to refinement of the risks for the patient subsets, with improved risk discrimination in patients with advanced-stage disease.

  16. Low-loss interference filter arrays made by plasma-assisted reactive magnetron sputtering (PARMS) for high-performance multispectral imaging

    Science.gov (United States)

    Broßmann, Jan; Best, Thorsten; Bauer, Thomas; Jakobs, Stefan; Eisenhammer, Thomas

    2016-10-01

    Optical remote sensing of the earth from air and space typically utilizes several channels in the visible and near infrared spectrum. Thin-film optical interference filters, mostly of narrow bandpass type, are applied to select these channels. The filters are arranged in filter wheels, arrays of discrete stripe filters mounted in frames, or patterned arrays on a monolithic substrate. Such multi-channel filter assemblies can be mounted close to the detector, which allows a compact and lightweight camera design. Recent progress in image resolution and sensor sensitivity requires improvements of the optical filter performance. Higher demands placed on blocking in the UV and NIR and in between the spectral channels, in-band transmission and filter edge steepness as well as scattering lead to more complex filter coatings with thicknesses in the range of 10 - 25μm. Technological limits of the conventionally used ion-assisted evaporation process (IAD) can be overcome only by more precise and higher-energetic coating technologies like plasma-assisted reactive magnetron sputtering (PARMS) in combination with optical broadband monitoring. Optics Balzers has developed a photolithographic patterning process for coating thicknesses up to 15μm that is fully compatible with the advanced PARMS coating technology. This provides the possibility of depositing multiple complex high-performance filters on a monolithic substrate. We present an overview of the performance of recently developed filters with improved spectral performance designed for both monolithic filter-arrays and stripe filters mounted in frames. The pros and cons as well as the resulting limits of the filter designs for both configurations are discussed.

  17. Reactive Atom Plasma Processing of Slumped Glass Wedges Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Reactive Atom Plasma (RAPTM) process will be evaluated as a rapid and practical method for fabricating precision wedges in glass sheets. The glass sheets are to...

  18. Synthesis of titanium carbide by induction plasma reactive spray

    Institute of Scientific and Technical Information of China (English)

    JIANG Xian-Liang(蒋显亮); M.Boulos

    2004-01-01

    A novel method capable of sufficient mixing of titanium powder and methane of carbon source was developed in the synthesis of titanium carbide by induction plasma reactive spray. X-ray diffraction analysis, optical microscopy, scanning electron microscopy, and microhardness test were used to characterize the spray-formed deposit.The experimental results show that both primary carburization of the titanium particles inside the plasma flame and secondary carburization of the growing deposit on high temperature substrate contribute to the forming of titanium carbide. The transitional phase of TiC1-x has the same crystal structure as TiC, but has a slightly low lattice constant. The deposit consists of fine grain structure and large grain structure. The fine grain structure, harder than large grain structure, shows grain boundary fracture.

  19. High hardness BaCb-(BxOy/BN) composites with 3D mesh-like fine grain-boundary structure by reactive spark plasma sintering.

    Science.gov (United States)

    Vasylkiv, Oleg; Borodianska, Hanna; Badica, Petre; Grasso, Salvatore; Sakka, Yoshio; Tok, Alfred; Su, Liap Tat; Bosman, Michael; Ma, Jan

    2012-02-01

    Boron carbide B4C powders were subject to reactive spark plasma sintering (also known as field assisted sintering, pulsed current sintering or plasma assisted sintering) under nitrogen atmosphere. For an optimum hexagonal BN (h-BN) content estimated from X-ray diffraction measurements at approximately 0.4 wt%, the as-prepared BaCb-(BxOy/BN) ceramic shows values of Berkovich and Vickers hardness of 56.7 +/- 3.1 GPa and 39.3 +/- 7.6 GPa, respectively. These values are higher than for the vacuum SPS processed B4C pristine sample and the h-BN -mechanically-added samples. XRD and electronic microscopy data suggest that in the samples produced by reactive SPS in N2 atmosphere, and containing an estimated amount of 0.3-1.5% h-BN, the crystallite size of the boron carbide grains is decreasing with the increasing amount of N2, while for the newly formed lamellar h-BN the crystallite size is almost constant (approximately 30-50 nm). BN is located at the grain boundaries between the boron carbide grains and it is wrapped and intercalated by a thin layer of boron oxide. BxOy/BN forms a fine and continuous 3D mesh-like structure that is a possible reason for good mechanical properties.

  20. Investigation of relationship between plasma gas temperature and reactive species

    Science.gov (United States)

    Doyama, Hideyuki; Kawano, Hiroaki; Takamatsu, Toshihiro; Matsumura, Yuriko; Miyahara, Hidekazu; Iwasawa, Atsuo; Azuma, Takeshi; Okino, Akitoshi

    2016-09-01

    In recent years, atmospheric non-thermal plasmas have attracted attention as a new sterilization device. In conventional plasma source, since the plasma gas temperature depends on the discharge power, influence of the plasma gas temperature on bactericidal ability by constant power has not been investigated. Therefore, we developed a new plasma source that can control the plasma gas temperature independently of the power, and it was shown that the bactericidal ability is increased with the plasma gas temperature. However, this factor has not been revealed. In this study, we investigated relationship between the bactericidal ability and the concentration of reactive species at each plasma gas temperature. Because reactive species generated by plasma are thought to affect sterilization. So, to investigate lifetime of the sterilizing factor bactericidal ability of Plasma Treated Water made by each gas temperature plasma was investigated. In both experiments, the correlation (R2 = 0.999) was observed between the concentration of singlet oxygen (1O2) and the bactericidal ability. These results show long-lifetime reactive species generated by 1O2 affects the bactericidal ability.

  1. Chemically reactive species in liquids generated by atmospheric-pressure plasmas and their roles in plasma medicine

    Energy Technology Data Exchange (ETDEWEB)

    Hamaguchi, Satoshi [Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2013-07-11

    Plasmas whose gas temperatures are close to room temperature may be generated in ambient air or a gas at atmospheric pressure with the use of low-frequency high voltage or low-power radio-frequency (RF) or microwave power applied to electrodes. Such plasmas can serve as a powerful source of free radicals and/or chemically reactive species that arise from atoms and molecules of the ambient gas. Recently use of such plasmas for medical purposes has attracted much attention as they can be implemented in possible medical devices that can cause blood coagulation, heal wounds, facilitate angiogenesis, sterilize surgical devices as well as living tissues without harming healthy cells, and selectively inactivate cancer cells. Especially of interest among reactive species generated by atmospheric-pressure plasmas (APP) are reactive oxygen species (ROS) and reactive nitrogen species (RNS) that are generated in liquid phase. Since most living tissues and cells are immersed in liquids (such as blood or culture media), reactive species generated by APPs in the gas phase are transported to the liquid phase and possibly converted to different types of reactive species therein before causing some influence on the tissues or cells. In this study, the rate equations are solved to evaluate concentrations of various reactive species in pure water that are originated by plasma reactions in atmosphere and possible effects of such species (including ROS/RNS) on living tissues and cells are discussed.

  2. Fast figuring of large optics by reactive atom plasma

    Science.gov (United States)

    Castelli, Marco; Jourdain, Renaud; Morantz, Paul; Shore, Paul

    2012-09-01

    The next generation of ground-based astronomical observatories will require fabrication and maintenance of extremely large segmented mirrors tens of meters in diameter. At present, the large production of segments required by projects like E-ELT and TMT poses time frames and costs feasibility questions. This is principally due to a bottleneck stage in the optical fabrication chain: the final figuring step. State-of-the-art figure correction techniques, so far, have failed to meet the needs of the astronomical community for mass production of large, ultra-precise optical surfaces. In this context, Reactive Atom Plasma (RAP) is proposed as a candidate figuring process that combines nanometer level accuracy with high material removal rates. RAP is a form of plasma enhanced chemical etching at atmospheric pressure based on Inductively Coupled Plasma technology. The rapid figuring capability of the RAP process has already been proven on medium sized optical surfaces made of silicon based materials. In this paper, the figure correction of a 3 meters radius of curvature, 400 mm diameter spherical ULE mirror is presented. This work demonstrates the large scale figuring capability of the Reactive Atom Plasma process. The figuring is carried out by applying an in-house developed procedure that promotes rapid convergence. A 2.3 μm p-v initial figure error is removed within three iterations, for a total processing time of 2.5 hours. The same surface is then re-polished and the residual error corrected again down to λ/20 nm rms. These results highlight the possibility of figuring a metre-class mirror in about ten hours.

  3. What Do Very Low Plasma Concentrations of High-sensitivity C-reactive Protein (hs-CRP) Mean among Healthy Middle-aged Koreans?

    OpenAIRE

    Kim, Min-Gul; Cho, Baik-Hwan; Chae, Soo-Wan; Park, Tae-Sun; Kim, Dal-Sik

    2015-01-01

    Background Systemic low-grade inflammation (SLGI), as assessed by measurements of high-sensitivity C-reactive protein (hs-CRP), is a strong independent risk factor for cardiovascular diseases (CVD). Although individuals with hs-CRP ≤ 1 mg/L have been defined as being at low risk according to AHA/CDC guidelines, the value of very low hs-CRP levels (

  4. Caracterisation of Titanium Nitride Layers Deposited by Reactive Plasma Spraying

    Science.gov (United States)

    Roşu, Radu Alexandru; Şerban, Viorel-Aurel; Bucur, Alexandra Ioana; Popescu, Mihaela; Uţu, Dragoş

    2011-01-01

    Forming and cutting tools are subjected to the intense wear solicitations. Usually, they are either subject to superficial heat treatments or are covered with various materials with high mechanical properties. In recent years, thermal spraying is used increasingly in engineering area because of the large range of materials that can be used for the coatings. Titanium nitride is a ceramic material with high hardness which is used to cover the cutting tools increasing their lifetime. The paper presents the results obtained after deposition of titanium nitride layers by reactive plasma spraying (RPS). As deposition material was used titanium powder and as substratum was used titanium alloy (Ti6Al4V). Macroscopic and microscopic (scanning electron microscopy) images of the deposited layers and the X ray diffraction of the coatings are presented. Demonstration program with layers deposited with thickness between 68,5 and 81,4 μm has been achieved and presented.

  5. Reactive species in non-equilibrium atmospheric-pressure plasmas: Generation, transport, and biological effects

    Science.gov (United States)

    Lu, X.; Naidis, G. V.; Laroussi, M.; Reuter, S.; Graves, D. B.; Ostrikov, K.

    2016-05-01

    Non-equilibrium atmospheric-pressure plasmas have recently become a topical area of research owing to their diverse applications in health care and medicine, environmental remediation and pollution control, materials processing, electrochemistry, nanotechnology and other fields. This review focuses on the reactive electrons and ionic, atomic, molecular, and radical species that are produced in these plasmas and then transported from the point of generation to the point of interaction with the material, medium, living cells or tissues being processed. The most important mechanisms of generation and transport of the key species in the plasmas of atmospheric-pressure plasma jets and other non-equilibrium atmospheric-pressure plasmas are introduced and examined from the viewpoint of their applications in plasma hygiene and medicine and other relevant fields. Sophisticated high-precision, time-resolved plasma diagnostics approaches and techniques are presented and their applications to monitor the reactive species and plasma dynamics in the plasma jets and other discharges, both in the gas phase and during the plasma interaction with liquid media, are critically reviewed. The large amount of experimental data is supported by the theoretical models of reactive species generation and transport in the plasmas, surrounding gaseous environments, and plasma interaction with liquid media. These models are presented and their limitations are discussed. Special attention is paid to biological effects of the plasma-generated reactive oxygen and nitrogen (and some other) species in basic biological processes such as cell metabolism, proliferation, survival, etc. as well as plasma applications in bacterial inactivation, wound healing, cancer treatment and some others. Challenges and opportunities for theoretical and experimental research are discussed and the authors' vision for the emerging convergence trends across several disciplines and application domains is presented to

  6. Reactive species in non-equilibrium atmospheric-pressure plasmas: Generation, transport, and biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Lu, X., E-mail: luxinpei@hotmail.com [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240 (China); Naidis, G.V. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Laroussi, M. [Plasma Engineering & Medicine Institute, Old Dominion University, Norfolk, VA 23529 (United States); Reuter, S. [Leibniz Institute for Plasma Science and Technology, Felix-Hausdorff-Strasse 2, 17489 Greifswald (Germany); Graves, D.B. [Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720 (United States); Ostrikov, K. [Institute for Future Environments, Queensland University of Technology, Brisbane, QLD 4000 (Australia); School of Physics, Chemistry, and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4000 (Australia); Commonwealth Scientific and Industrial Research Organization, P.O.Box 218, Lindfield, NSW 2070 (Australia); School of Physics, The University of Sydney, Sydney, NSW 2006 (Australia)

    2016-05-04

    Non-equilibrium atmospheric-pressure plasmas have recently become a topical area of research owing to their diverse applications in health care and medicine, environmental remediation and pollution control, materials processing, electrochemistry, nanotechnology and other fields. This review focuses on the reactive electrons and ionic, atomic, molecular, and radical species that are produced in these plasmas and then transported from the point of generation to the point of interaction with the material, medium, living cells or tissues being processed. The most important mechanisms of generation and transport of the key species in the plasmas of atmospheric-pressure plasma jets and other non-equilibrium atmospheric-pressure plasmas are introduced and examined from the viewpoint of their applications in plasma hygiene and medicine and other relevant fields. Sophisticated high-precision, time-resolved plasma diagnostics approaches and techniques are presented and their applications to monitor the reactive species and plasma dynamics in the plasma jets and other discharges, both in the gas phase and during the plasma interaction with liquid media, are critically reviewed. The large amount of experimental data is supported by the theoretical models of reactive species generation and transport in the plasmas, surrounding gaseous environments, and plasma interaction with liquid media. These models are presented and their limitations are discussed. Special attention is paid to biological effects of the plasma-generated reactive oxygen and nitrogen (and some other) species in basic biological processes such as cell metabolism, proliferation, survival, etc. as well as plasma applications in bacterial inactivation, wound healing, cancer treatment and some others. Challenges and opportunities for theoretical and experimental research are discussed and the authors’ vision for the emerging convergence trends across several disciplines and application domains is presented to

  7. Plasma Induced Physicochemical Changes and Reactive Dyeing of Wool Fabrics

    Directory of Open Access Journals (Sweden)

    J. Udakhe

    2015-01-01

    Full Text Available This study focuses on the effect of dielectric barrier discharge (DBD plasma treatment on physical and chemical properties of wool fabric and its relation to exhaustion of Drimalan Navy Blue FBI reactive dye. AFM analysis of plasma treated wool fabric has shown partial removal of epicuticle and thus reduced scale height. FD spectroscopy has shown improvement in hydrophilicity by many folds after plasma treatment. ATR graphs depict the removal of hydrophobic layer of 18-MEA and introduction of hydrophilic groups like cysteic acid after plasma treatment. Alkali solubility of wool fabric increases with increasing plasma treatment time. Wetting time for plasma treated fabric reduces drastically when compared to untreated wool fabric. It is found that plasma treated fabric takes much lesser time to reach maximum dye exhaustion than untreated fabric. Substantivity of the dye increases significantly after plasma treatment. Colour fastness properties improve with increase in plasma treatment time. Chemical oxygen demand (COD of spent dyebath liquor is found to reduce with increase in plasma treatment time. Biological oxygen demand (BOD is found to be higher for plasma treated samples, while ratio of COD/BOD has reduced with increase in the plasma treatment time.

  8. An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation.

    Science.gov (United States)

    Gorbanev, Yury; Soriano, Robert; O'Connell, Deborah; Chechik, Victor

    2016-11-03

    Non-thermal atmospheric pressure ('cold') plasmas have received increased attention in recent years due to their significant biomedical potential. The reactions of cold plasma with the surrounding atmosphere yield a variety of reactive species, which can define its effectiveness. While efficient development of cold plasma therapy requires kinetic models, model benchmarking needs empirical data. Experimental studies of the source of reactive species detected in aqueous solutions exposed to plasma are still scarce. Biomedical plasma is often operated with He or Ar feed gas, and a specific interest lies in investigation of the reactive species generated by plasma with various gas admixtures (O2, N2, air, H2O vapor, etc.) Such investigations are very complex due to difficulties in controlling the ambient atmosphere in contact with the plasma effluent. In this work, we addressed common issues of 'high' voltage kHz frequency driven plasma jet experimental studies. A reactor was developed allowing the exclusion of ambient atmosphere from the plasma-liquid system. The system thus comprised the feed gas with admixtures and the components of the liquid sample. This controlled atmosphere allowed the investigation of the source of the reactive oxygen species induced in aqueous solutions by He-water vapor plasma. The use of isotopically labelled water allowed distinguishing between the species originating in the gas phase and those formed in the liquid. The plasma equipment was contained inside a Faraday cage to eliminate possible influence of any external field. The setup is versatile and can aid in further understanding the cold plasma-liquid interactions chemistry.

  9. Interaction of nanosecond ultraviolet laser pulses with reactive dusty plasma

    Science.gov (United States)

    van de Wetering, F. M. J. H.; Oosterbeek, W.; Beckers, J.; Nijdam, S.; Gibert, T.; Mikikian, M.; Rabat, H.; Kovačević, E.; Berndt, J.

    2016-05-01

    Even though UV laser pulses that irradiate a gas discharge are small compared to the plasma volume (≲3%) and plasma-on time (≲6 × 10-6%), they are found to dramatically change the discharge characteristics on a global scale. The reactive argon-acetylene plasma allows the growth of nanoparticles with diameters up to 1 μm, which are formed inside the discharge volume due to spontaneous polymerization reactions. It is found that the laser pulses predominantly accelerate and enhance the coagulation phase and are able to suppress the formation of a dust void.

  10. plasmatis Center for Innovation Competence: Controlling reactive component output of atmospheric pressure plasmas in plasma medicine

    Science.gov (United States)

    Reuter, Stephan

    2012-10-01

    The novel approach of using plasmas in order to alter the local chemistry of cells and cell environment presents a significant development in biomedical applications. The plasmatis center for innovation competence at the INP Greifswald e.V. performs fundamental research in plasma medicine in two interdisciplinary research groups. The aim of our plasma physics research group ``Extracellular Effects'' is (a) quantitative space and time resolved diagnostics and modelling of plasmas and liquids to determine distribution and composition of reactive species (b) to control the plasma and apply differing plasma source concepts in order to produce a tailored output of reactive components and design the chemical composition of the liquids/cellular environment and (c) to identify and understand the interaction mechanisms of plasmas with liquids and biological systems. Methods to characterize the plasma generated reactive species from plasma-, gas- and liquid phase and their biological effects will be presented. The diagnostic spectrum ranges from absorption/emission/laser spectroscopy and molecular beam mass spectrometry to electron paramagnetic resonance spectroscopy and cell biological diagnostic techniques. Concluding, a presentation will be given of the comprehensive approach to plasma medicine in Greifswald where the applied and clinical research of the Campus PlasmaMed association is combined with the fundamental research at plasmatis center.

  11. Simulations of highly reactive fluids

    Energy Technology Data Exchange (ETDEWEB)

    Fried, L E; Manaa, M R; Reed, E J

    2005-07-21

    We report density functional molecular dynamics simulations to determine the early chemical events of hot (T = 3000 K) and dense (1.97 g/cm{sup 3}, V/V{sub 0} = 0.68) nitromethane (CH{sub 3}NO{sub 2}). The first step in the decomposition process is an intermolecular proton abstraction mechanism that leads to the formation of CH{sub 3}NO{sub 2}H and the aci ion H{sub 2}CNO{sub 2}{sup -}, in support of evidence from static high-pressure and shock experiments. An intramolecular hydrogen transfer that transforms nitromethane into the aci acid form, CH{sub 2}NO{sub 2}H, accompanies this event. This is the first confirmation of chemical reactivity with bond selectivity for an energetic material near the condition of fully reacted specimen. We also report the decomposition mechanism followed up to the formation of H{sub 2}O as the first stable product.

  12. Optical diagnostics of reactive species in atmospheric-pressure nonthermal plasma

    Science.gov (United States)

    Ono, Ryo

    2016-03-01

    This paper reviews optical measurements of reactive species in atmospheric-pressure nonthermal plasmas: streamer discharge, dielectric barrier discharge (DBD), plasma jet, and plasma-assisted ignition and combustion. Measurements of OH, O, N, {{\\text{O}}3} , NO, {{\\text{N}}2} (A, B, C), {{\\text{O}}2} (a, b), {{\\text{N}}2}(v) , {{\\text{O}}2}(v) , He*, Ar*, \\text{N}2+ , CH, and CH2O by laser-induced fluorescence, absorption, optical emission spectroscopy, and coherent anti-Stokes Raman scattering methods are included. Reactive species measurement in low-frequency (\\cong 1 Hz) pulsed streamer discharge is introduced, and reactive species production and reaction processes indicated by these measurements are described in detail. Measurements in high-frequency DBD, atmospheric-pressure diffuse discharge, and dc corona discharge are described. Measurements in plasma jets are also reviewed: rf plasma jets, kHz plasma jets, and additional plasma jets. Finally, measurements in plasma-assisted ignition and combustion are described and reviewed in addition to measurements in conventional spark ignition. A comprehensive list of the reviewed measurements is provided.

  13. Reactive spark plasma sintering of MgB2 in nitrogen atmosphere for the enhancement of the high-field critical current density

    Science.gov (United States)

    Badica, P.; Burdusel, M.; Popa, S.; Pasuk, I.; Ivan, I.; Borodianska, H.; Vasylkiv, O.; Kuncser, A.; Ionescu, A. M.; Miu, L.; Aldica, G.

    2016-10-01

    High density bulks (97%-99%) of MgB2 were prepared by spark plasma sintering (SPS) in nitrogen (N2) atmosphere for different heating rates (10, 20 and 100 °C min-1) and compared with reference samples processed in vacuum and Ar. N2 reacts with MgB2 and forms MgB9N along the MgB2 grain boundaries. The high-field critical current density is enhanced for the sample processed in N2 with a heating rate of 100 °C min-1. At 2-35 K, this sample shows the strongest contribution of the grain boundary pinning (GBP). All samples are in the point pinning (PP) limit and by increasing temperature the GBP contribution decreases.

  14. Reactive Spark Plasma Sintering: Successes and Challenges of Nanomaterial Synthesis

    Directory of Open Access Journals (Sweden)

    Dina V. Dudina

    2013-01-01

    Full Text Available Spark plasma sintering (SPS, initially developed as an advanced sintering technique for consolidating nanopowders into nanostructured bulk materials, has been recently looked at in much broader perspective and gained a strong reputation of a versatile method of solid state processing of metals, ceramics, and composites. The powders in the SPS-dies experience the action of pulsed electric current and uniaxial pressure; they are heated at very high rates unachievable in furnace heating and sintered within shorter times and at lower temperatures than in conventional methods. The principle of SPS and convenient design of the facilities make it attractive for conducting solid state synthesis. In this paper, based on our own results and the literature data, we analyze the microstructure formation of the products of chemical reactions occurring in the SPS in an attempt to formulate the requirements to the microstructure parameters of reactant mixtures and SPS conditions that should be fulfilled in order to produce a nanostructured material. We present successful syntheses of nanostructured ceramics and metal matrix composite with nanosized reinforcements in terms of microstructure stability and attractive properties of the materials and discuss the challenges of making a dense nanostructured material when reaction and densification do not coincide during the SPS. In the final part of the paper, we provide an outlook on the further uses of reactive SPS in the synthesis of nanostructured materials.

  15. Prognostic implications of plasma fibrinogen and serum C- reactive ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research March 2017; 16 (3): 665-672 ... reactive protein levels in non-small cell lung cancer ... as indicators of tumour resectability wherein a high tumour resection rate is possible in patients ... The World.

  16. Impact of plasma jet vacuum ultraviolet radiation on reactive oxygen species generation in bio-relevant liquids

    Energy Technology Data Exchange (ETDEWEB)

    Jablonowski, H.; Hammer, M. U.; Reuter, S. [Center for Innovation Competence plasmatis, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany); Leibniz Institute for Plasma Science and Technology, INP Greifswald e.V. Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany); Bussiahn, R.; Weltmann, K.-D.; Woedtke, Th. von [Leibniz Institute for Plasma Science and Technology, INP Greifswald e.V. Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

    2015-12-15

    Plasma medicine utilizes the combined interaction of plasma produced reactive components. These are reactive atoms, molecules, ions, metastable species, and radiation. Here, ultraviolet (UV, 100–400 nm) and, in particular, vacuum ultraviolet (VUV, 10–200 nm) radiation generated by an atmospheric pressure argon plasma jet were investigated regarding plasma emission, absorption in a humidified atmosphere and in solutions relevant for plasma medicine. The energy absorption was obtained for simple solutions like distilled water (dH{sub 2}O) or ultrapure water and sodium chloride (NaCl) solution as well as for more complex ones, for example, Rosewell Park Memorial Institute (RPMI 1640) cell culture media. As moderate stable reactive oxygen species, hydrogen peroxide (H{sub 2}O{sub 2}) was studied. Highly reactive oxygen radicals, namely, superoxide anion (O{sub 2}{sup •−}) and hydroxyl radicals ({sup •}OH), were investigated by the use of electron paramagnetic resonance spectroscopy. All species amounts were detected for three different treatment cases: Plasma jet generated VUV and UV radiation, plasma jet generated UV radiation without VUV part, and complete plasma jet including all reactive components additionally to VUV and UV radiation. It was found that a considerable amount of radicals are generated by the plasma generated photoemission. From the experiments, estimation on the low hazard potential of plasma generated VUV radiation is discussed.

  17. Impact of plasma jet vacuum ultraviolet radiation on reactive oxygen species generation in bio-relevant liquids

    Science.gov (United States)

    Jablonowski, H.; Bussiahn, R.; Hammer, M. U.; Weltmann, K.-D.; von Woedtke, Th.; Reuter, S.

    2015-12-01

    Plasma medicine utilizes the combined interaction of plasma produced reactive components. These are reactive atoms, molecules, ions, metastable species, and radiation. Here, ultraviolet (UV, 100-400 nm) and, in particular, vacuum ultraviolet (VUV, 10-200 nm) radiation generated by an atmospheric pressure argon plasma jet were investigated regarding plasma emission, absorption in a humidified atmosphere and in solutions relevant for plasma medicine. The energy absorption was obtained for simple solutions like distilled water (dH2O) or ultrapure water and sodium chloride (NaCl) solution as well as for more complex ones, for example, Rosewell Park Memorial Institute (RPMI 1640) cell culture media. As moderate stable reactive oxygen species, hydrogen peroxide (H2O2) was studied. Highly reactive oxygen radicals, namely, superoxide anion (O2•-) and hydroxyl radicals (•OH), were investigated by the use of electron paramagnetic resonance spectroscopy. All species amounts were detected for three different treatment cases: Plasma jet generated VUV and UV radiation, plasma jet generated UV radiation without VUV part, and complete plasma jet including all reactive components additionally to VUV and UV radiation. It was found that a considerable amount of radicals are generated by the plasma generated photoemission. From the experiments, estimation on the low hazard potential of plasma generated VUV radiation is discussed.

  18. High plasma C-reactive protein (CRP) is related to low paraoxonase-I (PON-I) activity independently of high leptin and low adiponectin in type 2 diabetes mellitus

    NARCIS (Netherlands)

    Dullaart, Robin P. F.; de Vries, Rindert; Sluiter, Wim J.; Voorbij, Hieronymus A. M.

    2009-01-01

    In type 2 diabetes mellitus, circulating C-reactive protein (CRP) is increased, whereas the high density lipoprotein (HDL)-associated, anti-oxidative and anti-inflammatory enzyme, paraoxonase-I, is decreased. Both high CRP and low paraoxonase-I activity may predict cardiovascular disease. It is unkn

  19. Influence of the reactive atmosphere on the formation of nanoparticles in the plasma plume induced by nanosecond pulsed laser irradiation of metallic targets at atmospheric pressure and high repetition rate

    Science.gov (United States)

    Girault, M.; Le Garrec, J.-L.; Mitchell, J. B. A.; Jouvard, J.-M.; Carvou, E.; Menneveux, J.; Yu, J.; Ouf, F.-X.; Carles, S.; Potin, V.; Pillon, G.; Bourgeois, S.; Perez, J.; Marco de Lucas, M. C.; Lavisse, L.

    2016-06-01

    The influence of a reactive atmosphere on the formation of nanoparticles (NPs) in the plasma plume generated by nanosecond pulsed laser irradiation of metal targets (Ti, Al, Ag) was probed in situ using Small Angle X-ray Scattering (SAXS). Air and different O2-N2 gas mixtures were used as reactive gas within atmospheric pressure. SAXS results showed the formation of NPs in the plasma-plume with a mean radius varying in the 2-5 nm range. A decrease of the NPs size with increasing the O2 percentage in the O2-N2 gas mixture was also showed. Ex situ observations by transmission electron microscopy and structural characterizations by X-ray diffraction and Raman spectroscopy were also performed for powders collected in experiments done using air as ambient gas. The stability of the different metal oxides is discussed as being a key parameter influencing the formation of NPs in the plasma-plume.

  20. Reactive high power impulse magnetron sputtering: combining simulation and experiment

    Science.gov (United States)

    Kozak, Tomas; Vlcek, Jaroslav

    2016-09-01

    Reactive high-power impulse magnetron sputtering (HiPIMS) has recently been used for preparation of various oxide films with high application potential, such as TiO2, ZrO2, Ta2O5, HfO2, VO2. Using our patented method of pulsed reactive gas flow control with an optimized reactive gas inlet, we achieved significantly higher deposition rates compared to typical continuous dc magnetron depositions. We have developed a time-dependent model of the reactive HiPIMS. The model includes a depth-resolved description of the sputtered target (featuring sputtering, implantation and knock-on implantation processes) and a parametric description of the discharge plasma (dissociation of reactive gas, ionization and return of sputtered atoms and gas rarefaction). The model uses a combination of experimental and simulation data as input. We have calculated the composition of the target and substrate for several deposition conditions. The simulations predict a reduced compound coverage of the target in HiPIMS compared to the continuous dc sputtering regime which explains the increased deposition rate. The simulations show that an increased dissociation of oxygen in a HiPIMS discharge is beneficial to achieve stoichiometric films on the substrate at high deposition rates.

  1. Thermonuclear reactivity of D-T fusion plasma with spin-polarized fuel

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Toshiki [Department of Electronic Engineering, Gunma Univ., Kiryu, Gunma (Japan); Nakao, Yasuyuki

    1999-04-01

    The thermonuclear reactivity of deuterium(D) - tritium(T) fusion plasma with spin-polarized fuel has been studied. Two mechanisms of depolarization, collisions and waves, in the high temperature fusion plasma have been considered. The binary collisions have been found not to change the nuclear spin states. The waves with a frequency of a few GHz, however, changes the spin states appreciably, when {delta}B/B{sub 0} (the ratio of the amplitude of the fluctuating magnetic field to the external field) becomes larger than 10{sup -5}. (author)

  2. Associations Between Diabetic Retinopathy and Plasma Levels of High-sensitive C-reactive Protein or Von Willebrand Factor in Long-term Type 1 Diabetic Patients

    DEFF Research Database (Denmark)

    Laursen, Jonas Vejvad Nørskov; Hoffmann, Stine Skovbo; Green, Anders

    2013-01-01

    Treatment Diabetic Retinopathy Study (ETDRS) adaptation of the modified Airlie House classification of DR. Results: Median age and duration of diabetes were 58.7 and 43 years, respectively. Median levels (10th-90th percentile) of hs-CRP and von Willebrand factor antigen were 1.31 mg/l (0.37-13.3 mg/l) and 1...... a population-based cohort from Fyn County, Denmark. Plasma levels of hs-CRP and von Willebrand factor antigen were measured and related to the level of diabetic retinopathy (DR) as evaluated by dilated nine-field 45 degree monoscopic fundus photos captured by Topcon TRC-NWS6 and graded according to the Early.......27 IU/ml (0.79-2.07 IU/ml), respectively. No or minimal DR (ETDRS-levels 10-20) was found in 16.4%, mild DR (ETDRS-level 35) in 19.4%, moderate DR (ETDRS-levels 43-47) in 11.0%, and 53.2% had proliferative diabetic retinopathy (PDR) corresponding to ETDRS-level 60 or more. In an age- and sex...

  3. Influence of the reactive atmosphere on the formation of nanoparticles in the plasma plume induced by nanosecond pulsed laser irradiation of metallic targets at atmospheric pressure and high repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Girault, M. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Le Garrec, J.-L.; Mitchell, J.B.A. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Jouvard, J.-M. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Carvou, E. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Menneveux, J.; Yu, J. [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Ouf, F.-X. [Institut de Radioprotection et de Sureté Nucléaire IRSN/PSN-RES/SCA/LPMA BP 68, 91192 Gif-Sur-Yvette (France); Carles, S. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Potin, V.; Pillon, G.; Bourgeois, S. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Perez, J. [Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex (France); Marco de Lucas, M.C., E-mail: delucas@u-bourgogne.fr [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); and others

    2016-06-30

    Highlights: • NPs formed in a plasma-plume during laser irradiation of metals (Al, Ti, Ag) were studied. • In situ SAXS and ex situ TEM, XRD and Raman spectra were measured. • NPs size decreased when increasing the O{sub 2} fraction in a controlled O{sub 2}+N{sub 2} atmosphere. • The oxidation of metal NPs in the plasma restricts the increase of the size of the NPs. - Abstract: The influence of a reactive atmosphere on the formation of nanoparticles (NPs) in the plasma plume generated by nanosecond pulsed laser irradiation of metal targets (Ti, Al, Ag) was probed in situ using Small Angle X-ray Scattering (SAXS). Air and different O{sub 2}–N{sub 2} gas mixtures were used as reactive gas within atmospheric pressure. SAXS results showed the formation of NPs in the plasma-plume with a mean radius varying in the 2–5 nm range. A decrease of the NPs size with increasing the O{sub 2} percentage in the O{sub 2}–N{sub 2} gas mixture was also showed. Ex situ observations by transmission electron microscopy and structural characterizations by X-ray diffraction and Raman spectroscopy were also performed for powders collected in experiments done using air as ambient gas. The stability of the different metal oxides is discussed as being a key parameter influencing the formation of NPs in the plasma-plume.

  4. Control of Reactive Species Generated by Low-frequency Biased Nanosecond Pulse Discharge in Atmospheric Pressure Plasma Effluent

    Science.gov (United States)

    Takashima, Keisuke; Kaneko, Toshiro

    2016-09-01

    The control of hydroxyl radical and the other gas phase species generation in the ejected gas through air plasma (air plasma effluent) has been experimentally studied, which is a key to extend the range of plasma treatment. Nanosecond pulse discharge is known to produce high reduced electric field (E/N) discharge that leads to efficient generation of the reactive species than conventional low frequency discharge, while the charge-voltage cycle in the low frequency discharge is known to be well-controlled. In this study, the nanosecond pulse discharge biased with AC low frequency high voltage is used to take advantages of these discharges, which allows us to modulate the reactive species composition in the air plasma effluent. The utilization of the gas-liquid interface and the liquid phase chemical reactions between the modulated long-lived reactive species delivered from the air plasma effluent could realize efficient liquid phase chemical reactions leading to short-lived reactive species production far from the air plasma, which is crucial for some plasma agricultural applications.

  5. Consumption of both low and high (-)-epicatechin apple puree attenuates platelet reactivity and increases plasma concentrations of nitric oxide metabolites: A randomized controlled trial

    NARCIS (Netherlands)

    Gasper, A.; Hollands, W.; Casgrain, A.; Saha, S.; Teucher, B.; Dainty, J.R.; Venema, D.P.; Hollman, P.C.H.

    2014-01-01

    We hypothesised that consumption of flavanol-containing apple puree would modulate platelet activity and increase nitric oxide metabolite status, and that high flavanol apple puree would exert a greater effect than low flavanol apple puree. 25 subjects consumed 230 g of apple puree containing 25 and

  6. Consumption of both low and high (-)-epicatechin apple puree attenuates platelet reactivity and increases plasma concentrations of nitric oxide metabolites: A randomized controlled trial

    NARCIS (Netherlands)

    Gasper, A.; Hollands, W.; Casgrain, A.; Saha, S.; Teucher, B.; Dainty, J.R.; Venema, D.P.; Hollman, P.C.H.

    2014-01-01

    We hypothesised that consumption of flavanol-containing apple puree would modulate platelet activity and increase nitric oxide metabolite status, and that high flavanol apple puree would exert a greater effect than low flavanol apple puree. 25 subjects consumed 230 g of apple puree containing 25 and

  7. Investigation of opening switch mechanisms based on chemically reactive plasmas

    Science.gov (United States)

    Lapatovich, W. P.; Piejak, R. B.; Proud, J. M.

    1985-11-01

    An investigation of discharge-induced chemical reactions resulting in high-density product vapors containing strongly attaching gases has been conducted to evaluate the feasibility and potential of such reactions in rapid opening plasma switches. This new concept of employing such reactions to limit and/or interrupt large currents on a microsecond time scale was studied in two element (electrodeless and electroded) devices and in three element (electroded) devices. Bimolecular and unimolecular reactions were considered. The plasma reaction between AlCl sub 3 and SiO sub 2 was studied. The electrical properties of one of the reaction products (SiCl sub 4) is reported.

  8. Surface treatment of diamond-like carbon films by reactive Ar/CF{sub 4} high-power pulsed magnetron sputtering plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Takashi, E-mail: t-kimura@nitech.ac.jp [Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Nishimura, Ryotaro [Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Azuma, Kingo [Department of Electrical Engineering and Computer Sciences, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280 (Japan); Nakao, Setsuo; Sonoda, Tsutomu; Kusumori, Takeshi; Ozaki, Kimihiro [National Institute of Advanced Industrial Science and Technology (AIST) - Chubu, 2266-98 Anagahora, Moriyama, Nagoya 463-8560 (Japan)

    2015-12-15

    Surface modification of diamond-like carbon films deposited by a high-power pulsed magnetron sputtering (HPPMS) of Ar was carried out by a HPPMS of Ar/CF{sub 4} mixture, changing a CF{sub 4} fraction from 2.5% to 20%. The hardness of the modified films markedly decreased from about 13 to about 3.5 GPa with increasing CF{sub 4} fraction, whereas the water contact angle of the modified films increased from 68° to 109° owing to the increase in the CF{sub x} content on the film surface. C 1s spectra in X-ray photoelectron spectroscopy indicated that a graphitic structure of modified films was formed at CF{sub 4} fractions less than 5%, above which the modified films possessed a polymer-like structure. Influence of treatment time on the properties of the modified films was also investigated in the range of treatment time from 5 to 30 min. The properties of the modified films did not depend on the treatment time in the range of treatment time longer than 10 min, whereas the water contact angle was not sensitive to the treatment time at any treatment time.

  9. High Throughput Plasma Water Treatment

    Science.gov (United States)

    Mujovic, Selman; Foster, John

    2016-10-01

    The troublesome emergence of new classes of micro-pollutants, such as pharmaceuticals and endocrine disruptors, poses challenges for conventional water treatment systems. In an effort to address these contaminants and to support water reuse in drought stricken regions, new technologies must be introduced. The interaction of water with plasma rapidly mineralizes organics by inducing advanced oxidation in addition to other chemical, physical and radiative processes. The primary barrier to the implementation of plasma-based water treatment is process volume scale up. In this work, we investigate a potentially scalable, high throughput plasma water reactor that utilizes a packed bed dielectric barrier-like geometry to maximize the plasma-water interface. Here, the water serves as the dielectric medium. High-speed imaging and emission spectroscopy are used to characterize the reactor discharges. Changes in methylene blue concentration and basic water parameters are mapped as a function of plasma treatment time. Experimental results are compared to electrostatic and plasma chemistry computations, which will provide insight into the reactor's operation so that efficiency can be assessed. Supported by NSF (CBET 1336375).

  10. [Determination of capillary plasma C-reactive protein during therapy for acute infectious lung diseases].

    Science.gov (United States)

    Makarenko, V V; Vavilikhina, N F; Kastrikina, T N; El'chaninova, S A

    2011-06-01

    Changes in the concentration of C-reactive protein (CRP), leukocytes, erythrocyte sedimentation rate, and differential blood count were comparatively estimated in the treatment of 66 infants (aged 1.12 +/- 0.95 years) with acute infectious lung diseases. There was a high correlation between capillary plasma and venous serum CRP concentrations. On the first day of effective antibiotic therapy, there was a significant decrease in CRP levels; the sensitivity and specificity were 96 and 94%, respectively. Thus, measurement of capillary blood CRP is an accessible and informative tool to monitor therapy for infectious lung diseases in infants.

  11. Gammaherpesvirus-driven plasma cell differentiation regulates virus reactivation from latently infected B lymphocytes.

    Science.gov (United States)

    Liang, Xiaozhen; Collins, Christopher M; Mendel, Justin B; Iwakoshi, Neal N; Speck, Samuel H

    2009-11-01

    Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68) gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency) account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners) that do not directly participate in virus replication, but rather facilitate virus reactivation by

  12. Gammaherpesvirus-driven plasma cell differentiation regulates virus reactivation from latently infected B lymphocytes.

    Directory of Open Access Journals (Sweden)

    Xiaozhen Liang

    2009-11-01

    Full Text Available Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68 gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners that do not directly participate in virus replication, but rather facilitate virus

  13. Thermodynamics of High Temperature Plasmas

    Directory of Open Access Journals (Sweden)

    Ettore Minardi

    2009-03-01

    Full Text Available In this work we discuss how and to what extent the thermodynamic concepts and the thermodynamic formalism can be extended to the description of high temperature states of the plasma not necessarily associated with a Boltzmann distribution and with thermal equilibrium.The discussion is based on the “magnetic or electrostatic entropy concept”, an interpretative and predictive tool based on probability and information, defined in a suitably coarse-grained possibility space of all current density or of all electric charge density distributions under testable constraints, and whose variation properties are proven to be related under certain conditions to the equilibrium and the stability of the system. In the case of magnetic equilibrium the potentiality of the magnetic entropy concept is illustrated by comparing the predictions of the current density and pressure profiles with the observations in different tokamak machines and different tokamak regimes, as well as by showing how the equilibrium and the stability in devices as different as the reversed field pinch or the magnetic well are described by the variation properties of the same entropy functional applied to the different situations. In fact it emerges that the maximum of the entropy can be seen in these different cases as an optimization constraint for the minimum of the magnetic energy. The application of the entropy concept to the electrostatic processes shows in particular that the so-called reactive instabilities (non-dissipative, non-resonant instabilities with a marginal point admit a neighboring state with higher entropy and are therefore of special relevance from the point of view of the physical evolution of the system. In this case the thermodynamic formalism allows the introduction of the concept of “thermodynamic fluctuations” of the macroscopic charge density and provides a method for the calculation of the “thermodynamic” fluctuation levels both on the stable as

  14. Longitudinal Relationship between Plasma Reactive Oxygen Metabolites and Periodontal Condition in the Maintenance Phase of Periodontal Treatment

    Directory of Open Access Journals (Sweden)

    Tatsuya Machida

    2014-01-01

    Full Text Available Aim. The present cohort study describes the longitudinal relationship between plasma oxidative status and periodontitis progression during the maintenance phase of treatment. Materials and Methods. Forty-five patients (mean age 58.8 years were monitored from 2008 to 2013. Periodontal conditions, including probing pocket depth (PPD and clinical attachment level (CAL, were recorded. Measurements of plasma reactive oxygen metabolites (ROM and biologic antioxidant potential (BAP were performed to evaluate plasma oxidative status. The patients were assigned into 2 groups as low and high plasma ROM level using a cut-off value which was median of plasma ROM level at baseline. Results. In the subjects with low plasma ROM level at baseline, changes in mean CAL were positively correlated with changes in plasma ROM levels, bleeding on probing, and plaque control record, but not with PPD. In the subjects with high plasma ROM at baseline, changes in CAL were significantly associated with only PPD at baseline. On the other hands there were no significant associations between changes in CAL and those in plasma BAP levels. Conclusions. When plasma ROM level in periodontitis patients was low, increases in plasma ROM level were associated with those in CAL during the maintenance phase of treatment.

  15. Reactive Plasma Sprayed TiN Coating and Its Thermal Stability

    Institute of Scientific and Technical Information of China (English)

    ZOU Dong-li; YAN Dian-ran; HE Ji-ning; LI Xiang-zhi; DONG Yan-chun; ZHANG Jian-xin

    2007-01-01

    TiN coating was prepared by reactive plasma spraying in the Ar and N2 containing plasma jet. The results of XRD show that the TiN coating consists of TiN and Ti3O, neither Ti2N nor TiO2 phases. The toughening mechanism was characterized by analyzing the SEM morphologies of the TiN coating's indentation of microhardness and fracture surfaces. The results indicate that the coating possesses a high toughness. The adhesion strength among the TiN layers is 25.88 MPa, which is slightly lower than that of the Ni/Al bonding coating. The oxidation process of the RPS TiN coating is TiN→Ti3O→TiO2.

  16. A simple and straightforward expression for curling probe electron density diagnosis in reactive plasmas

    Science.gov (United States)

    Arshadi, Ali; Brinkmann, Ralf Peter; Hotta, Masaya; Nakamura, Keiji

    2017-04-01

    Active plasma resonance spectroscopy (APRS) refers to the family of plasma diagnostic methods which utilize the ability of plasmas to resonate at frequencies close to the plasma frequency. APRS operates by exciting the plasma with a weak RF signal by means of a small electric probe. The response of the plasma is recorded by a network analyzer (NA). A mathematical model is applied to derive characteristics like the electron density and the electron temperature. The curling probe is a promising realization of APRS. The curling probe is well-qualified for the local measurement of the electron density in reactive plasmas. This spiral probe resonates in plasma at a larger density dependent frequency than the plasma frequency. This manuscript represents a simple and straightforward expression relating this resonance frequency to the electron density of the plasma. A good agreement is observed between the proposed expression and the results obtained from previous studies and numerical simulations.

  17. Tracing the plasma interactions for pulsed reactive crossed-beam laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jikun; Stender, Dieter; Pichler, Markus; Pergolesi, Daniele; Schneider, Christof W.; Wokaun, Alexander; Lippert, Thomas, E-mail: thomas.lippert@psi.ch [General Energy Research Department, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland); Döbeli, Max [Ion Beam Physics, ETH Zurich, CH-8093 Zurich (Switzerland)

    2015-10-28

    Pulsed reactive crossed-beam laser ablation is an effective technique to govern the chemical activity of plasma species and background molecules during pulsed laser deposition. Instead of using a constant background pressure, a gas pulse with a reactive gas, synchronized with the laser beam, is injected into vacuum or a low background pressure near the ablated area of the target. It intercepts the initially generated plasma plume, thereby enhancing the physicochemical interactions between the gaseous environment and the plasma species. For this study, kinetic energy resolved mass-spectrometry and time-resolved plasma imaging were used to study the physicochemical processes occurring during the reactive crossed beam laser ablation of a partially {sup 18}O substituted La{sub 0.6}Sr{sub 0.4}MnO{sub 3} target using oxygen as gas pulse. The characteristics of the ablated plasma are compared with those observed during pulsed laser deposition in different oxygen background pressures.

  18. Studies on Nanocrystalline TiN Coatings Prepared by Reactive Plasma Spraying

    Directory of Open Access Journals (Sweden)

    Dong Yanchun

    2008-01-01

    Full Text Available Titanium nitride (TiN coatings with nanostructure were prepared on the surface of 45 steel (Fe-0.45%C via reactive plasma spraying (denoted as RPS Ti powders using spraying gun with self-made reactive chamber. The microstructural characterization, phases constitute, grain size, microhardness, and wear resistance of TiN coatings were systematically investigated. The grain size was obtained through calculation using the Scherrer formula and observed by TEM. The results of X-ray diffraction and electron diffraction indicated that the TiN is main phase of the TiN coating. The forming mechanism of the nano-TiN was characterized by analyzing the SEM morphologies of surface of TiN coating and TiN drops sprayed on the surface of glass, and observing the temperature and velocity of plasma jet using Spray Watch. The tribological properties of the coating under nonlubricated condition were tested and compared with those of the AISI M2 high-speed steel and Al2O3 coating. The results have shown that the RPS TiN coating presents better wear resistance than the M2 high-speed steel and Al2O3 coating under nonlubricated condition. The microhardness of the cross-section and longitudinal section of the TiN coating was tested. The highest hardness of the cross-section of TiN coating is 1735.43HV100 g.

  19. Recent developments of DSMC within the reactive plasma flow solver PICLas

    Science.gov (United States)

    Reschke, W.; Binder, T.; Kleinert, J.; Mirza, A.; Nizenkov, P.; Pfeiffer, M.; Fasoulas, S.; Copplestone, S.; Ortwein, P.; Munz, C. D.

    2016-11-01

    In order to enable the numerical simulation of rarefied plasma flows in thermal and chemical non-equilibrium, electro-magnetic interactions as well as particle collisions have to be considered. A common approach is to use particle-based methods. The Particle-in-Cell (PIC) method simulates charged collisionless gas flows by solving the Vlasov-Maxwell equation system while particle collisions in neutral reactive flows are treated by the Direct Simulation Monte Carlo (DSMC) method. Therefore, PICLas is being developed, a coupled simulation code that enables three-dimensional particle-based simulations combining high-order PIC and DSMC schemes for the simulation of reactive, rarefied plasma flows. PICLas enables time-accurate simulations on unstructured hexahedral meshes and is parallelized for high-performance computing. In addition to an overview of PICLas, the current development status of the DSMC module is presented. This includes the relaxation of polyatomic gases, the extension of the chemical modeling to gas-surface interactions, and the implementation of steady-state detection routines.

  20. Helicon Discharge with Selectable Nitrogen Reactive Species Production as a Plasma Source for III-group Nitrides Growth by MBE

    Science.gov (United States)

    Biloiu, Costel; Doss, Forest; Scime, Earl

    2004-11-01

    Plasma assisted molecular beam epitaxy (PAMBE) of III-N materials is a potential alternative to MOCVD for fabrication of high quality wide band gap semiconductor devices. In the helicon plasma source, it may be possible to control the population of specific reactive nitrogen species by modification of the electron energy distribution function through the resonant wave-particle interaction arising from electrons traveling at same velocity as the helicon wave phase velocity. We report preliminary results on control of reactive nitrogen species performed in a steady state, high density, helicon plasma source CHEWIE (Compact HElicon Waves and Instabilities Experiment). The helicon vacuum chamber is a 12 cm long, Pyrex tube, 6 cm in diameter, connected to a stainless steel diffusion chamber. RF power of up to 1.0 kW over a frequency range of 3-28 MHz is used to create the steady state plasma. A 7 cm long, half wave, m = +1, helical antenna couples the rf energy into the plasma. A single solenoidal magnetic field coil surrounds the source and is capable of generating axial magnetic fields up to 600 G. Optical emission spectroscopy investigations show that under certain conditions, the decay from the long lived A^3Σ_u^+ state dominates the emission spectrum of the plasma.

  1. Reactivity of water vapor in an atmospheric argon flowing post-discharge plasma torch

    CERN Document Server

    Collette, S; Reniers, F

    2016-01-01

    The reactivity of water vapor introduced in the flowing post-discharge of an RF atmospheric plasma torch is investigated through electrical characterization, optical emission spectroscopy and mass spectrometry measurements. Due to the technical features of the plasma torch, the post-discharge can be considered as divided into two regions: an inner region (inside the plasma torch device) where the water vapor is injected and an outer region which directly interacts with the ambient air. The main reactions induced by the injection of water vapor are identified as well as those indicative of the influence of the ambient air. Plausible pathways allowing the production of H, OH, O radicals and H2O2 are discussed as well as reactions potentially responsible for inhomogeneities and for a low DC current measured in the flowing post-discharge. Keywords: atmospheric post-discharge, H2O plasma reactivity, RF plasma torch

  2. Does Reactive Thrombocytosis Observed in Iron Deficiency Anemia Affect Plasma Viscosity?

    Directory of Open Access Journals (Sweden)

    Selami K. Toprak

    2012-09-01

    Full Text Available OBJECTIVE: The accompanying thrombocytosis is referred to as the major factor associated with thromboembolism in iron deficiency anemia (IDA. Increased viscosity may increase the risk of thrombosis. We hypothesized that increased platelet count -with reactive thrombocytosis- might also affect plasma viscosity. We planned to evaluate the influence of normal and high platelet count on plasma viscosity in IDA patients. METHODS: The patient population consisted of fifty-three newly diagnosed and untreated women aged between 18 and 62 years with IDA. Group 1 consisted of 33 patients, platelet levels below 400 x 109/L. Group 2 consisted of 20 patients, platelet levels above 400 x 109/L. Measurements of plasma viscosity were performed using Brookfield viscometer. RESULTS: Mean plasma viscosity was found as 1.05 ± 0.08 mPa.s. in Group 1, and 1.03 ± 0.06 mPa.s. in Group 2. Mean plasma viscosity was not statistically different. White blood cell count was significantly higher in Group 2. Vitamin B12 levels were significantly higher in Group 2, while folic acid levels were higher in Group 1 (p=0.011 and p=0.033. Plasma viscosity was correlated with erythrocyte sedimentation rate (r=0.512 p=0.002 in Group 1 and inversely correlated with vitamin B12 (r=−0.480 p=0.032 in Group 2. CONCLUSION: Despite the significant difference between groups in terms of platelet count, no significant difference was detected in plasma viscosity and this finding could be explained as the following; 1-These platelets were not thrombocythemic platelets; 2-Similar to the theory about leukocytes, higher platelet counts – even non-thrombocythemic – may increase plasma viscosity; 3-Evaluating platelet count alone is not sufficient and the associating red-cell deformability should also be taken into account; and 4-Although other diseases that could affect viscosity are excluded, some definitely proven literature criteria such as fibrinogen, hyperlipidemia, and the inflammatory

  3. On the Inclusion of Inorganic Chemical Reactivity in High School Chemistry: The Reactivity Network.

    Science.gov (United States)

    Mellon, E. K.

    1989-01-01

    Reports the function of the Reactivity Network which is to translate reactivity data from the primary literature into some 30 reviews for high school teachers and curriculum developers and to disseminate that information nationwide. Discusses a needs assessment done for the project. (MVL)

  4. Deposition of titanium nitride layers by electric arc - Reactive plasma spraying method

    Energy Technology Data Exchange (ETDEWEB)

    Serban, Viorel-Aurel [University ' Politehnica' of Timisoara, Faculty of Mechanical Engineering, No. 1 Mihai Viteazu Boulevard, 300222 Timisoara (Romania); Rosu, Radu Alexandru, E-mail: raduniz@gmail.com [University ' Politehnica' of Timisoara, Faculty of Mechanical Engineering, No. 1 Mihai Viteazu Boulevard, 300222 Timisoara (Romania); Bucur, Alexandra Ioana [National Institute for Research and Development in Electrochemistry and Condensed Matter Timisoara, Analysis and Characterization Department, No. 1 P Andronescu Street, Timisoara 300224 (Romania); Pascu, Doru Romulus [Romania National Research and Development Institute for Welding and Material Testing Timisoara, No. 30 Mihai Viteazu Boulevard, 300222 Timisoara (Romania)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Titanium nitride layers deposited by electric arc - reactive plasma spraying method. Black-Right-Pointing-Pointer Deposition of titanium nitride layers on C45 steel at different spraying distances. Black-Right-Pointing-Pointer Characterization of the coatings hardness as function of the spraying distances. Black-Right-Pointing-Pointer Determination of the corrosion behavior of titanium nitride layers obtained. - Abstract: Titanium nitride (TiN) is a ceramic material which possesses high mechanical properties, being often used in order to cover cutting tools, thus increasing their lifetime, and also for covering components which are working in corrosive environments. The paper presents the experimental results on deposition of titanium nitride coatings by a new combined method (reactive plasma spraying and electric arc thermal spraying). In this way the advantages of each method in part are combined, obtaining improved quality coatings in the same time achieving high productivity. Commercially pure titanium wire and C45 steel as substrate were used for experiments. X-ray diffraction analysis shows that the deposited coatings are composed of titanium nitride (TiN, Ti{sub 2}N) and small amounts of Ti{sub 3}O. The microstructure of the deposited layers, investigated both by optical and scanning electron microscopy, shows that the coatings are dense, compact, without cracks and with low porosity. Vickers microhardness of the coatings presents maximum values of 912 HV0.1. The corrosion tests in 3%NaCl solution show that the deposited layers have a high corrosion resistance compared to unalloyed steel substrate.

  5. Influence of nitrogen admixture to argon on the ion energy distribution in reactive high power pulsed magnetron sputtering of chromium

    Science.gov (United States)

    Breilmann, W.; Maszl, C.; Hecimovic, A.; von Keudell, A.

    2017-04-01

    Reactive high power impulse magnetron sputtering (HiPIMS) of metals is of paramount importance for the deposition of various oxides, nitrides and carbides. The addition of a reactive gas such as nitrogen to an argon HiPIMS plasma with a metal target allows the formation of the corresponding metal nitride on the substrate. The addition of a reactive gas introduces new dynamics into the plasma process, such as hysteresis, target poisoning and the rarefaction of two different plasma gases. We investigate the dynamics for the deposition of chromium nitride by a reactive HiPIMS plasma using energy- and time-resolved ion mass spectrometry, fast camera measurements and temporal and spatially resolved optical emission spectroscopy. It is shown that the addition of nitrogen to the argon plasma gas significantly changes the appearance of the localized ionization zones, the so-called spokes, in HiPIMS plasmas. In addition, a very strong modulation of the metal ion flux within each HiPIMS pulse is observed, with the metal ion flux being strongly suppressed and the nitrogen molecular ion flux being strongly enhanced in the high current phase of the pulse. This behavior is explained by a stronger return effect of the sputtered metal ions in the dense plasma above the racetrack. This is best observed in a pure nitrogen plasma, because the ionization zones are mostly confined, implying a very high local plasma density and consequently also an efficient scattering process.

  6. Deposition of titanium nitride and hydroxyapatite-based biocompatible composite by reactive plasma spraying

    Science.gov (United States)

    Roşu, Radu Alexandru; Şerban, Viorel-Aurel; Bucur, Alexandra Ioana; Dragoş, Uţu

    2012-02-01

    Titanium nitride is a bioceramic material successfully used for covering medical implants due to the high hardness meaning good wear resistance. Hydroxyapatite is a bioactive ceramic that contributes to the restoration of bone tissue, which together with titanium nitride may contribute to obtaining a superior composite in terms of mechanical and bone tissue interaction matters. The paper presents the experimental results in obtaining composite layers of titanium nitride and hydroxyapatite by reactive plasma spraying in ambient atmosphere. X-ray diffraction analysis shows that in both cases of powders mixtures used (10% HA + 90% Ti; 25% HA + 75% Ti), hydroxyapatite decomposition occurred; in variant 1 the decomposition is higher compared with the second variant. Microstructure of the deposited layers was investigated using scanning electron microscope, the surfaces presenting a lamellar morphology without defects such as cracks or microcracks. Surface roughness values obtained vary as function of the spraying distance, presenting higher values at lower thermal spraying distances.

  7. Study of Plasma Malondialdehyde, Troponin I and C - Reactive protein in Acute Coronary Syndromes Patients

    Directory of Open Access Journals (Sweden)

    S. Shams

    2006-04-01

    Full Text Available Introduction & Objective: Ischemic injury of endothelium is associated with prostaglandin synthesis and platelet adhesion and aggregation, which may be associated with the release of aldehydes such as malondialdehyde (MDA. C-reactive protein and cardiac troponin I have been proposed as diagnostic markers of acute coronary syndromes. In this study, we compared the usefulness of plasma MDA as a marker of acute coronary syndromes with that of C-reactive protein and troponin I.Material & Methods: The study population contained 50 patients with unstable angina and 50 patients with acute myocardial infarction admitted to the hearth department of the Ekbatan Hospital of Hamadan. The subjects were matched according to age and sex. Total cholesterol, LDL and HDL cholesterol, triglycerides, plasma MDA, troponin I and C-reactive protein levels were determined in all patients. Results: Results showed that the plasma MDA levels were significantly higher in patients with acute myocardial infarction than in individuals with unstable angina (P<0.001 and were associated with increased levels of troponin I and C-reactive protein (P<0.001.Conclusion: The combination of the plasma MDA levels, which reflect endothelial injury, and troponin I and C-reactive protein levels may allow better discrimination in acute coronary syndromes patients.

  8. Schlieren High Speed Imaging on Fluid Flow in Liquid Induced by Plasma-driven Interfacial Forces

    Science.gov (United States)

    Lai, Janis; Foster, John

    2016-10-01

    Effective plasma-based water purification depends heavily on the transport of plasma-derived reactive species from the plasma into the liquid. Plasma interactions at the liquid-gas boundary are known to drive circulation in the bulk liquid. This forced circulation is not well understood. A 2-D plasma- in-liquid water apparatus is currently being investigated as a means to study the plasma-liquid interface to understand not only reactive species flows but to also understand plasma- driven fluid dynamic effects in the bulk fluid. Using Schlieren high speed imaging, plasma-induced density gradients near the interfacial region and into the bulk solution are measured to investigate the nature of these interfacial forces. Plasma-induced flow was also measured using particle imaging velocimetry. NSF CBET 1336375 and DOE DE-SC0001939.

  9. Reactive oxygen plasma-enabled synthesis of nanostructured CdO: tailoring nanostructures through plasma-surface interactions

    Energy Technology Data Exchange (ETDEWEB)

    Cvelbar, Uros; Mozetic, Miran [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Ostrikov, Kostya [CSIRO Materials Science and Engineering, PO Box 218, Lindfield NSW 2070 (Australia)], E-mail: Uros.Cvelbar@ijs.si, E-mail: Kostya.Ostrikov@csiro.au

    2008-10-08

    Plasma-assisted synthesis of nanostructures is one of the most precise and effective approaches used in nanodevice fabrication. Here we report on the innovative approach of synthesizing nanostructured cadmium oxide films on Cd substrates using a reactive oxygen plasma-based process. Under certain conditions, the surface morphology features arrays of crystalline CdO nano/micropyramids. These nanostructures grow via unconventional plasma-assisted oxidation of a cadmium foil exposed to inductively coupled plasmas with a narrow range of process parameters. The growth of the CdO pyramidal nanostructures takes place in the solid-liquid-solid phase, with the rates determined by the interaction of plasma-produced oxygen atoms and ions with the surface. It is shown that the size of the pyramidal structures can be effectively controlled by the fluxes of oxygen atoms and ions impinging on the cadmium surface. The unique role of the reactive plasma environment in the controlled synthesis of CdO nanopyramidal structures is discussed as well.

  10. Polygenic Overlap Between C-Reactive Protein, Plasma Lipids, and Alzheimer Disease.

    Science.gov (United States)

    Desikan, Rahul S; Schork, Andrew J; Wang, Yunpeng; Thompson, Wesley K; Dehghan, Abbas; Ridker, Paul M; Chasman, Daniel I; McEvoy, Linda K; Holland, Dominic; Chen, Chi-Hua; Karow, David S; Brewer, James B; Hess, Christopher P; Williams, Julie; Sims, Rebecca; O'Donovan, Michael C; Choi, Seung Hoan; Bis, Joshua C; Ikram, M Arfan; Gudnason, Vilmundur; DeStefano, Anita L; van der Lee, Sven J; Psaty, Bruce M; van Duijn, Cornelia M; Launer, Lenore; Seshadri, Sudha; Pericak-Vance, Margaret A; Mayeux, Richard; Haines, Jonathan L; Farrer, Lindsay A; Hardy, John; Ulstein, Ingun Dina; Aarsland, Dag; Fladby, Tormod; White, Linda R; Sando, Sigrid B; Rongve, Arvid; Witoelar, Aree; Djurovic, Srdjan; Hyman, Bradley T; Snaedal, Jon; Steinberg, Stacy; Stefansson, Hreinn; Stefansson, Kari; Schellenberg, Gerard D; Andreassen, Ole A; Dale, Anders M

    2015-06-09

    Epidemiological findings suggest a relationship between Alzheimer disease (AD), inflammation, and dyslipidemia, although the nature of this relationship is not well understood. We investigated whether this phenotypic association arises from a shared genetic basis. Using summary statistics (P values and odds ratios) from genome-wide association studies of >200 000 individuals, we investigated overlap in single-nucleotide polymorphisms associated with clinically diagnosed AD and C-reactive protein (CRP), triglycerides, and high- and low-density lipoprotein levels. We found up to 50-fold enrichment of AD single-nucleotide polymorphisms for different levels of association with C-reactive protein, low-density lipoprotein, high-density lipoprotein, and triglyceride single-nucleotide polymorphisms using a false discovery rate threshold <0.05. By conditioning on polymorphisms associated with the 4 phenotypes, we identified 55 loci associated with increased AD risk. We then conducted a meta-analysis of these 55 variants across 4 independent AD cohorts (total: n=29 054 AD cases and 114 824 healthy controls) and discovered 2 genome-wide significant variants on chromosome 4 (rs13113697; closest gene, HS3ST1; odds ratio=1.07; 95% confidence interval=1.05-1.11; P=2.86×10(-8)) and chromosome 10 (rs7920721; closest gene, ECHDC3; odds ratio=1.07; 95% confidence interval=1.04-1.11; P=3.38×10(-8)). We also found that gene expression of HS3ST1 and ECHDC3 was altered in AD brains compared with control brains. We demonstrate genetic overlap between AD, C-reactive protein, and plasma lipids. By conditioning on the genetic association with the cardiovascular phenotypes, we identify novel AD susceptibility loci, including 2 genome-wide significant variants conferring increased risk for AD. © 2015 American Heart Association, Inc.

  11. A new reactive atom plasma technology (RAPT) for precision machining: the etching of ULE optical surfaces

    Science.gov (United States)

    Fanara, Carlo; Shore, Paul; Nicholls, John R.; Lyford, Nicholas; Sommer, Phil; Fiske, Peter

    2006-06-01

    The next generation of 30-100 metre diameter extremely large telescopes (ELTs) requires large numbers of hexagonal primary mirror segments. As part of the Basic Technology programme run jointly by UCL and Cranfield University, a reactive atomic plasma technology (RAP(tm)) emerged from the US Lawrence Livermore National Laboratory (LLNL), is employed for the finishing of these surfaces. Results are presented on this novel etching technology. The Inductively Coupled Plasma (ICP) operated at atmospheric pressure using argon, activates the chemical species injected through its centre and promotes the fluorine-based chemical reactions at the surface. Process assessment trials on Ultra Low Expansion (ULE(tm)) plates, previously ground at high material removal rates, have been conducted. The quality of the surfaces produced on these samples using the RAP process are discussed. Substantial volumetric material removal rates of up to 0.446(21) mm 3/s at the highest process speed (1,200 mm/min) were found to be possible without pre-heating the substrate. The influences of power transfer, process speed and gas concentration on the removal rates have been determined. The suitability of the RAP process for revealing and removing sub-surface damage induced by high removal rate grinding is discussed. The results on SiC samples are reported elsewhere in this conference.

  12. Dense Plasma Focus - From Alternative Fusion Source to Versatile High Energy Density Plasma Source for Plasma Nanotechnology

    Science.gov (United States)

    Rawat, R. S.

    2015-03-01

    The dense plasma focus (DPF), a coaxial plasma gun, utilizes pulsed high current electrical discharge to heat and compress the plasma to very high density and temperature with energy densities in the range of 1-10 × 1010 J/m3. The DPF device has always been in the company of several alternative magnetic fusion devices as it produces intense fusion neutrons. Several experiments conducted on many different DPF devices ranging over several order of storage energy have demonstrated that at higher storage energy the neutron production does not follow I4 scaling laws and deteriorate significantly raising concern about the device's capability and relevance for fusion energy. On the other hand, the high energy density pinch plasma in DPF device makes it a multiple radiation source of ions, electron, soft and hard x-rays, and neutrons, making it useful for several applications in many different fields such as lithography, radiography, imaging, activation analysis, radioisotopes production etc. Being a source of hot dense plasma, strong shockwave, intense energetic beams and radiation, etc, the DPF device, additionally, shows tremendous potential for applications in plasma nanoscience and plasma nanotechnology. In the present paper, the key features of plasma focus device are critically discussed to understand the novelties and opportunities that this device offers in processing and synthesis of nanophase materials using, both, the top-down and bottom-up approach. The results of recent key experimental investigations performed on (i) the processing and modification of bulk target substrates for phase change, surface reconstruction and nanostructurization, (ii) the nanostructurization of PLD grown magnetic thin films, and (iii) direct synthesis of nanostructured (nanowire, nanosheets and nanoflowers) materials using anode target material ablation, ablated plasma and background reactive gas based synthesis and purely gas phase synthesis of various different types of

  13. Reactive species in humidity containing atmospheric pressure plasma jets - Numerical and experimental investigations

    Science.gov (United States)

    Schroeter, Sandra; Bredin, J.; Wijaikhum, A.; West, A.; Dedrick, J.; Niemi, K.; Gibson, A. R.; Foucher, M.; Booth, J.-P.; de Oliveira, N.; Joyeux, D.; Nahon, L.; Gorbanev, Y.; Chechik, V.; Wagenaars, E.; Gans, T.; O'Connell, D.

    2016-09-01

    The formation and absolute densities of oxygen and hydrogen containing reactive species such as atomic oxygen (O), hydrogen (H), hydroxyl radicals (OH) and hydrogen peroxide (H2O2) in an atmospheric pressure plasma jet (APPJ) are investigated as a function of the humidity content in the helium feed gas. APPJs are effective sources for these species, which are known to be biologically active and form a central role in their potential for biomedical applications. To develop and tailor APPJs for therapeutics, quantification of the reactive species produced is necessary. In this work, different diagnostic techniques, such as UV and VUV absorption spectroscopy and picosecond two-photon absorption laser-induced fluorescence (ps-TALIF) and a 0-dimensional chemical kinetics model are applied. We find that the densities of hydrogen containing species increase non-linearly with increasing feed gas humidity. The trend of atomic oxygen depends strongly on impurities present in the APPJ. The model results show that the dominant formation and destruction mechanisms of the species of interest are strongly influenced by the humidity content with different processes dominating at high and low humidity. Supported by UK EPSRC (EP/K018388/1, EP/H003797/1), the York-Paris CIRC and LABEX Plas@par (ANR11-IDEX-0004-02).

  14. Reactive Plasma-Sprayed Aluminum Nitride-Based Coating Thermal Conductivity

    Science.gov (United States)

    Shahien, Mohammed; Yamada, Motohiro; Fukumoto, Masahiro; Egota, Kazumi; Okamoto, Kenji

    2015-12-01

    Recently, thick aluminum nitride/alumina (AlN/Al2O3) composite coatings were successfully fabricated through the reactive plasma spraying of fine Al2O3/AlN mixture in the N2/H2 atmospheric plasma. The coatings consist of AlN, Al5O6N, γ-Al2O3, and α-Al2O3 phases. This study will evaluate the thermal conductivity of these complicated plasma-sprayed coatings and optimize the controlling aspects. Furthermore, the influence of the process parameters on the coatings thermal conductivity will be investigated. The fabricated coatings showed very low thermal conductivity (2.43 W/m K) compared to the AlN sintered compacts. It is attributed to the phase composition of the fabricated coatings, oxide content, and porosity. The presence of Al2O3, Al5O6N and the high coating porosity decreased its thermal conductivity. The presence of oxygen in the AlN lattice creates Al vacancies which lead to phonon scattering and therefore suppressed the thermal conductivity. The formation of γ-Al2O3 phase in the coating leads to further decrease in its conductivity, due to its lower density compared to the α-phase. Moreover, the high porosity of the coating strongly suppressed the conductivity. This is due to the complicated microstructure of plasma spray coatings (splats, porosity, and interfaces, particularly in case of reactive spray process), which obviously lowered the conductivity. Furthermore, the measured coating density was lower than the AlN value and suppressed the coating conductivity. In addition, the spraying parameter showed a varied effect on the coating phase composition, porosity, density, and therefore on its conductivity. Although the N2 gas flow improved the nitride content, it suppressed the thermal conductivity gradually. It is attributed to the further increase in the porosity and further decrease in the density of the coatings with the N2 gas. Furthermore, increasing the arc did not show a significant change on the coating thermal conductivity. On the other hand

  15. A road to hydrogenating graphene by a reactive ion etching plasma

    NARCIS (Netherlands)

    Wojtaszek, M.; Tombros, N.; Caretta, A.; van Loosdrecht, P. H. M.; van Wees, B. J.

    2011-01-01

    We report the hydrogenation of single and bilayer graphene by an argon-hydrogen plasma produced in a reactive ion etching (RIE) system. Electronic transport measurements in combination with Raman spectroscopy are used to link the electric mean free path to the optically extracted defect

  16. Gas-liquid interfacial plasmas producing reactive species for cell membrane permeabilization

    Science.gov (United States)

    Kaneko, Toshiro; Sasaki, Shota; Takashima, Keisuke; Kanzaki, Makoto

    2017-01-01

    Gas-liquid interfacial atmospheric-pressure plasma jets (GLI-APPJ) are used medically for plasma-induced cell-membrane permeabilization. In an attempt to identify the dominant factors induced by GLI-APPJ responsible for enhancing cell-membrane permeability, the concentration and distribution of plasma-produced reactive species in the gas and liquid phase regions are measured. These reactive species are classified in terms of their life-span: long-lived (e.g., H2O2), short-lived (e.g., O2•−), and extremely-short-lived (e.g., •OH). The concentration of plasma-produced •OHaq in the liquid phase region decreases with an increase in solution thickness (plasma-induced cell-membrane permeabilization is found to decay markedly as the thickness of the solution increases. Furthermore, the horizontally center-localized distribution of •OHaq, resulting from the center-peaked distribution of •OH in the gas phase region, corresponds with the distribution of the permeabilized cells upon APPJ irradiation, whereas the overall plasma-produced oxidizing species such as H2O2aq in solution exhibit a doughnut-shaped horizontal distribution. These results suggest that •OHaq is likely one of the dominant factors responsible for plasma-induced cell-membrane permeabilization. PMID:28163376

  17. Relativistic QED Plasma at Extremely High Temperature

    CERN Document Server

    Masood, Samina S

    2016-01-01

    Renormalization scheme of QED (Quantum Electrodynamics) at high temperatures is used to calculate the effective parameters of relativistic plasma in the early universe. Renormalization constants of QED play role of effective parameters of the theory and can be used to determine the collective behavior of the medium. We explicitly show that the dielectric constant, magnetic reluctivity, Debye length and the plasma frequency depend on temperature in the early universe. Propagation speed, refractive index, plasma frequency and Debye shielding length of a QED plasma are computed at extremely high temperatures in the early universe. We also found the favorable conditions for the relativistic plasma from this calculations.

  18. Prognostic value of plasma C-reactive protein in the evaluation of paraquat poisoning patients

    Institute of Scientific and Technical Information of China (English)

    Zong NingΔ; Yu-Long BaiΔ; Hua Lu; Kang-Lin Mo

    2015-01-01

    Objective:To investigate the prognostic value of plasma C-reactive protein (CRP) level in patients with paraquat poisoning. Methods: This study included 162 patients with paraquat poisoning. The data of plasma paraquat,CRP level and arterial blood gas were analyzed. Cox regression analysis was applied to evaluate the risk factors of prognosis. Receiver operating characteristics curve analysis and area under curve were used to calculate the predictive power of significant variable. Differences in patient survival were determined using the Kaplan-Meier method and a log-rank test. Results:PlasmaCRP level was significantly increased in non-survival patients compared with survival patients (P Conclusions: These results suggest that plasmaCRP level is distinct increased in patients with paraquat poisoning, and the plasmaCRP level may be useful for the prediction of prognosis in paraquat poisoning.

  19. Method for atmospheric pressure reactive atom plasma processing for surface modification

    Science.gov (United States)

    Carr, Jeffrey W.

    2009-09-22

    Reactive atom plasma processing can be used to shape, polish, planarize and clean the surfaces of difficult materials with minimal subsurface damage. The apparatus and methods use a plasma torch, such as a conventional ICP torch. The workpiece and plasma torch are moved with respect to each other, whether by translating and/or rotating the workpiece, the plasma, or both. The plasma discharge from the torch can be used to shape, planarize, polish, and/or clean the surface of the workpiece, as well as to thin the workpiece. The processing may cause minimal or no damage to the workpiece underneath the surface, and may involve removing material from the surface of the workpiece.

  20. A microfluidic chip for generating reactive plasma at gas-gas interface formed in laminar flow

    Science.gov (United States)

    Hashimoto, Masahiro; Tsukasaki, Katsuki; Kumagai, Shinya; Sasaki, Minoru

    2015-01-01

    A gas-gas interface is used for generating a localized reactive plasma flow at an atmospheric pressure. A microfluidic chip is fabricated as the reactor integrating a small plasma source located upstream. Within a Y-shaped microchannel, a discharging gas flows with a chemical gas. Owing to the small width of the microchannel, the gas flow is stabilized in a laminar flow. The resultant gas-gas interface is formed in the area where two gases flow facing each other activating the chemical gas through the energetic species in the discharging gas. A characteristic stream pattern is observed as the etching profile of a carbon film with a sub-µm sharp step change that can be explained by the spatial distribution of the reactive oxygen. This etching profile is different from that obtained when plasma discharging occurs near the channel exit being affected by the turbulent flow.

  1. Apparatus and method for atmospheric pressure reactive atom plasma processing for shaping of damage free surfaces

    Science.gov (United States)

    Carr; Jeffrey W.

    2009-03-31

    Fabrication apparatus and methods are disclosed for shaping and finishing difficult materials with no subsurface damage. The apparatus and methods use an atmospheric pressure mixed gas plasma discharge as a sub-aperture polisher of, for example, fused silica and single crystal silicon, silicon carbide and other materials. In one example, workpiece material is removed at the atomic level through reaction with fluorine atoms. In this example, these reactive species are produced by a noble gas plasma from trace constituent fluorocarbons or other fluorine containing gases added to the host argon matrix. The products of the reaction are gas phase compounds that flow from the surface of the workpiece, exposing fresh material to the etchant without condensation and redeposition on the newly created surface. The discharge provides a stable and predictable distribution of reactive species permitting the generation of a predetermined surface by translating the plasma across the workpiece along a calculated path.

  2. Structural modification of the skin barrier by OH radicals: a reactive molecular dynamics study for plasma medicine

    Science.gov (United States)

    Van der Paal, J.; Verlackt, C. C.; Yusupov, M.; Neyts, E. C.; Bogaerts, A.

    2015-04-01

    While plasma treatment of skin diseases and wound healing has been proven highly effective, the underlying mechanisms, and more generally the effect of plasma radicals on skin tissue, are not yet completely understood. In this paper, we perform ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of plasma generated OH radicals with a model system composed of free fatty acids, ceramides, and cholesterol molecules. This model system is an approximation of the upper layer of the skin (stratum corneum). All interaction mechanisms observed in our simulations are initiated by H-abstraction from one of the ceramides. This reaction, in turn, often starts a cascade of other reactions, which eventually lead to the formation of aldehydes, the dissociation of ceramides or the elimination of formaldehyde, and thus eventually to the degradation of the skin barrier function.

  3. Obese Hypertensive Men Have Plasma Concentrations of C-Reactive Protein Similar to That of Obese Normotensive Men

    DEFF Research Database (Denmark)

    Asferg, Camilla L; Andersen, Ulrik B; Linneberg, Allan

    2014-01-01

    plasma CRP concentrations are also closely associated with obesity. It is uncertain whether CRP is directly involved in the pathogenesis of hypertension or is only a marker of other pathogenic processes closely related to obesity. METHODS: We studied 103 obese men (body mass index (BMI) ≥ 30.0 kg/m(2......BACKGROUND: Low-grade chronic inflammation is a characteristic feature of obesity, the most important lifestyle risk factor for hypertension. Elevated plasma concentrations of the inflammatory biomarker C-reactive protein (CRP) are associated with an increased risk of hypertension, but elevated...... participants were medication-free. We measured plasma CRP concentrations with a high-sensitivity assay and determined body composition by dual energy x-ray absorptiometry scanning. RESULTS: There were no differences in anthropometric measures (BMI, waist circumference, or total fat mass percentage) between OHT...

  4. High-beta plasma blobs in the morningside plasma sheet

    Directory of Open Access Journals (Sweden)

    G. Haerendel

    Full Text Available Equator-S frequently encountered, i.e. on 30% of the orbits between 1 March and 17 April 1998, strong variations of the magnetic field strength of typically 5–15-min duration outside about 9RE during the late-night/early-morning hours. Very high-plasma beta values were found, varying between 1 and 10 or more. Close conjunctions between Equator-S and Geotail revealed the spatial structure of these "plasma blobs" and their lifetime. They are typically 5–10° wide in longitude and have an antisymmetric plasma or magnetic pressure distribution with respect to the equator, while being altogether low-latitude phenomena 
    (≤ 15°. They drift slowly sunward, exchange plasma across the equator and have a lifetime of at least 15–30 min. While their spatial structure may be due to some sort of mirror instability, little is known about the origin of the high-beta plasma. It is speculated that the morningside boundary layer somewhat further tailward may be the source of this plasma. This would be consistent with the preference of the plasma blobs to occur during quiet conditions, although they are also found during substorm periods. The relation to auroral phenomena in the morningside oval is uncertain. The energy deposition may be mostly too weak to generate a visible signature. However, patchy aurora remains a candidate for more disturbed periods.

    Key words. Magnetospheric physics (plasma convection; plasma sheet; plasma waves and instabilities

  5. Merging of high speed argon plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Case, A.; Messer, S.; Brockington, S.; Wu, L.; Witherspoon, F. D. [HyperV Technologies Corp., Chantilly, Virginia 22180 (United States); Elton, R. [University of Maryland, College Park, Maryland 20742 (United States)

    2013-01-15

    Formation of an imploding plasma liner for the plasma liner experiment (PLX) requires individual plasma jets to merge into a quasi-spherical shell of plasma converging on the origin. Understanding dynamics of the merging process requires knowledge of the plasma phenomena involved. We present results from the study of the merging of three plasma jets in three dimensional geometry. The experiments were performed using HyperV Technologies Corp. 1 cm Minirailguns with a preionized argon plasma armature. The vacuum chamber partially reproduces the port geometry of the PLX chamber. Diagnostics include fast imaging, spectroscopy, interferometry, fast pressure probes, B-dot probes, and high speed spatially resolved photodiodes, permitting measurements of plasma density, temperature, velocity, stagnation pressure, magnetic field, and density gradients. These experimental results are compared with simulation results from the LSP 3D hybrid PIC code.

  6. Deposition of titanium nitride layers by electric arc - Reactive plasma spraying method

    Science.gov (United States)

    Şerban, Viorel-Aurel; Roşu, Radu Alexandru; Bucur, Alexandra Ioana; Pascu, Doru Romulus

    2013-01-01

    Titanium nitride (TiN) is a ceramic material which possesses high mechanical properties, being often used in order to cover cutting tools, thus increasing their lifetime, and also for covering components which are working in corrosive environments. The paper presents the experimental results on deposition of titanium nitride coatings by a new combined method (reactive plasma spraying and electric arc thermal spraying). In this way the advantages of each method in part are combined, obtaining improved quality coatings in the same time achieving high productivity. Commercially pure titanium wire and C45 steel as substrate were used for experiments. X-ray diffraction analysis shows that the deposited coatings are composed of titanium nitride (TiN, Ti2N) and small amounts of Ti3O. The microstructure of the deposited layers, investigated both by optical and scanning electron microscopy, shows that the coatings are dense, compact, without cracks and with low porosity. Vickers microhardness of the coatings presents maximum values of 912 HV0.1. The corrosion tests in 3%NaCl solution show that the deposited layers have a high corrosion resistance compared to unalloyed steel substrate.

  7. Effect of air plasma treatment on the dyeing of Tencel fabric with C.I. Reactive Black 5

    Science.gov (United States)

    Zhang, L. S.; Liu, H. L.; Yu, W. D.

    2015-02-01

    The Tencel fabrics were treated by the atmospheric pressure plasma with air for different length of time and dyed with the C.I. Reactive Black 5 at 1%, 5% and 10% o.m.f. The effect of the prolonged plasma treatment time was characterized by both the weight loss and the whiteness index analyses, which implied that with the increase of the plasma treatment time, the treated fabrics were lighter and yellower than the untreated ones. The contact angle decreased dramatically from 139° to instantly spread. The results of SEM showed that, with the prolonged treatment time, more significant crater-like surface morphology on the fiber of Tencel samples was formed. Compared with untreated samples, the values of dye bath exhaustion and total fixation effect were higher. But they did not increase with the prolonged plasma treatment time. With the prolonged storage time after the plasma treatment, the result to ageing effect indicated that the values of dye bath exhaustion and total fixation effect reduced. The Integ values for characterizing the coloring effect were evaluated by the CIE system of color measurement. In most cases, the Integ values reached the highest ones when the plasma treatment time was 10 or 20 min. When the concentration of the dye bath was low (at 1% o.m.f.), the longer plasma treatment time was, the higher the Integ value was. However, if the fabrics after plasma treatment were stored for 21 days, the longer plasma treatment time did not cause the larger Integ value. When the concentration was 1%, the Integ value increased with the weight loss increasing, which was different from the values of fabrics with 5% and 10% concentration. If the dyeing concentration was low, the fixation had a more significant effect on the color fastness to wet rubbing; in contrast, if the dyeing concentration was high, the surface roughness had a more important effect on it.

  8. Trial of Growth Control of Farm-raised Fish by Plasma-generated Reactive Species

    Science.gov (United States)

    Motomura, Hideki; Kubota, Yoshiki; Fukushima, Ryo; Ikeda, Yoshihisa; Jinno, Masafumi

    2016-09-01

    As one of the biological applications of plasmas, growth control of agricultural products attracts attentions. There are many papers on growth enhancement of crops by plasma treatment. However, there are few published papers concerning growth enhancement of fishery products excepting reports of goldfish growth enhancement in 1980s. In this study, growth characteristics of edible fish (tilapia) under the plasma treatment has been investigated. An arc discharge reactor was employed and plasma treated air was introduced to two aquariums with a flow rate of 2.5 L/min. Measured concentrations of main reactive species were 43 ppm for NO, 23 ppm for NO2 and 7.5 ppm for O3. Each aquarium had 60 L capacity and contained 15 tilapia fish. The plasma treated air was supplied to an aquarium once a day and to the other aquarium twice a day with total duration of 10 min. Compared to no plasma treatment case, the growth rate decreased by 18% by once a day plasma treatment, whereas almost same growth rate was observed by twice a day plasma treatment. A possible reason of growth suppression is excess concentrations of nitrite and nitrate in water. The relationship between their concentrations and growth characteristics under several treatment conditions will be shown at the conference. Tirapia fish was supplied from SEFREC of Ehime University.

  9. Prognostic value of plasma C-reactive protein in the evaluation of paraquat poisoning patients简

    Institute of Scientific and Technical Information of China (English)

    Zong; Ning; Yu-Long; Bai; Hua; Lu; Kang-Lin; Mo

    2015-01-01

    Objective: To investigate the prognostic value of plasma C-reactive protein(CRP) level in patients with paraquat poisoning.Methods: This study included 162 patients with paraquat poisoning. The data of plasma paraquat, CRP level and arterial blood gas were analyzed. Cox regression analysis was applied to evaluate the risk factors of prognosis. Receiver operating characteristics curve analysis and area under curve were used to calculate the predictive power of significant variable. Differences in patient survival were determined using the Kaplan–Meier method and a log-rank test.Results: Plasma CRP level was significantly increased in non-survival patients compared with survival patients(P < 0.05), and positively correlated with plasma paraquat level(P < 0.05). Cox regression analysis revealed that plasma CRP level was an independent prognostic marker of mortality within 30 days. The receiver operating characteristics curve analysis indicated that area under curve of plasma CRP level was0.867(95% CI: 0.81–0.93), and the cut-off value was 18 mg/L, and patients with CRP level over this value had a poor survival time compared with those with less than this value.Conclusions: These results suggest that plasma CRP level is distinct increased in patients with paraquat poisoning, and the plasma CRP level may be useful for the prediction of prognosis in paraquat poisoning.

  10. Targeting cancer cells with reactive oxygen and nitrogen species generated by atmospheric-pressure air plasma.

    Directory of Open Access Journals (Sweden)

    Hak Jun Ahn

    Full Text Available The plasma jet has been proposed as a novel therapeutic method for cancer. Anticancer activity of plasma has been reported to involve mitochondrial dysfunction. However, what constituents generated by plasma is linked to this anticancer process and its mechanism of action remain unclear. Here, we report that the therapeutic effects of air plasma result from generation of reactive oxygen/nitrogen species (ROS/RNS including H2O2, Ox, OH-, •O2, NOx, leading to depolarization of mitochondrial membrane potential and mitochondrial ROS accumulation. Simultaneously, ROS/RNS activate c-Jun NH2-terminal kinase (JNK and p38 kinase. As a consequence, treatment with air plasma jets induces apoptotic death in human cervical cancer HeLa cells. Pretreatment of the cells with antioxidants, JNK and p38 inhibitors, or JNK and p38 siRNA abrogates the depolarization of mitochondrial membrane potential and impairs the air plasma-induced apoptotic cell death, suggesting that the ROS/RNS generated by plasma trigger signaling pathways involving JNK and p38 and promote mitochondrial perturbation, leading to apoptosis. Therefore, administration of air plasma may be a feasible strategy to eliminate cancer cells.

  11. Ionized gas (plasma) delivery of reactive oxygen species (ROS) into artificial cells

    Science.gov (United States)

    Hong, Sung-Ha; Szili, Endre J.; Jenkins, A. Toby A.; Short, Robert D.

    2014-09-01

    This study was designed to enhance our understanding of how reactive oxygen species (ROS), generated ex situ by ionized gas (plasma), can affect the regulation of signalling processes within cells. A model system, comprising of a suspension of phospholipid vesicles (cell mimics) encapsulating a ROS reporter, was developed to study the plasma delivery of ROS into cells. For the first time it was shown that plasma unequivocally delivers ROS into cells over a sustained period and without compromising cell membrane integrity. An important consideration in cell and biological assays is the presence of serum, which significantly reduced the transfer efficiency of ROS into the vesicles. These results are key to understanding how plasma treatments can be tailored for specific medical or biotechnology applications. Further, the phospholipid vesicle ROS reporter system may find use in other studies involving the application of free radicals in biology and medicine.

  12. Effects of butter high in ruminant trans and monounsaturated fatty acids on lipoproteins, incorporation of fatty acids into lipid classes, plasma C-reactive protein, oxidative stress, hemostatic variables, and insulin in healthy young men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Raff, M.; Basu, S.

    2006-01-01

    the effect of butter with a naturally high content of vaccenic acid and a concomitantly higher content of monounsaturated FAs on classic and novel risk markers of IHD. Design: In a double-blind, randomized, 5-wk, parallel intervention study, 42 healthy young men were given 115 g fat/d from test butter...... that was high in vaccenic acid (3.6 g vaccenic acid/d) or a control butter with a low content of vaccenic acid. Blood and urine samples were collected before and after the intervention. Results: The intake of the vaccenic acid-rich diet resulted in 6% and 9% lower total cholesterol and plasma HDL......-cholesterol concentrations, respectively, than did the intake of the control diet (P = 0.05 and 0.002, respectively), whereas the ratio of total to HDL cholesterol did not differ significantly between the groups. The FA composition of lipid classes reflected the FAs' proportion of the test butter. No other differences were...

  13. Calcium influx through TRP channels induced by short-lived reactive species in plasma-irradiated solution.

    Science.gov (United States)

    Sasaki, Shota; Kanzaki, Makoto; Kaneko, Toshiro

    2016-05-12

    Non-equilibrium helium atmospheric-pressure plasma (He-APP), which allows for a strong non-equilibrium chemical reaction of O2 and N2 in ambient air, uniquely produces multiple extremely reactive products, such as reactive oxygen species (ROS), in plasma-irradiated solution. We herein show that relatively short-lived unclassified reactive species (i.e., deactivated within approximately 10 min) generated by the He-APP irradiation can trigger physiologically relevant Ca(2+) influx through ruthenium red- and SKF 96365-sensitive Ca(2+)-permeable channel(s), possibly transient receptor potential channel family member(s). Our results provide novel insight into understanding of the interactions between cells and plasmas and the mechanism by which cells detect plasma-induced chemically reactive species, in addition to facilitating development of plasma applications in medicine.

  14. Kinetic theory of transport processes in partially ionized reactive plasma, II: Electron transport properties

    Science.gov (United States)

    Zhdanov, V. M.; Stepanenko, A. A.

    2016-11-01

    The previously obtained in (Zhdanov and Stepanenko, 2016) general transport equations for partially ionized reactive plasma are employed for analysis of electron transport properties in molecular and atomic plasmas. We account for both elastic and inelastic interaction channels of electrons with atoms and molecules of plasma and also the processes of electron impact ionization of neutral particles and three-body ion-electron recombination. The system of scalar transport equations for electrons is discussed and the expressions for non-equilibrium corrections to electron ionization and recombination rates and the diagonal part of the electron pressure tensor are derived. Special attention is paid to analysis of electron energy relaxation during collisions with plasma particles having internal degrees of freedom and the expression for the electron coefficient of inelastic energy losses is deduced. We also derive the expressions for electron vector and tensorial transport fluxes and the corresponding transport coefficients for partially ionized reactive plasma, which represent a generalization of the well-known results obtained by Devoto (1967). The results of numerical evaluation of contribution from electron inelastic collisions with neutral particles to electron transport properties are presented for a series of molecular and atomic gases.

  15. Effect of process parameters on induction plasma reactive deposition of tungsten carbide from tungsten metal powder

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Tungsten carbide deposit was made directly from tungsten metal powder through the reaction with methane in radio frequency induction plasma. Effect of major process parameters on the induction plasma reactive deposition of tungsten carbide was studied by optical microscopy, scanning electron microscopy, X-ray diffraction analysis, water displacement method, and microhardness test. The results show that methane flow rate, powder feed rate, particle size, reaction chamber pressure and deposition distance have significant influences on the phase composition, density, and microhardness of the deposit. Extra carbon is necessary to ensure the complete conversion of tungsten metal into the carbide.

  16. Nanosize stabilization of cubic and tetragonal phases in reactive plasma synthesized zirconia powders

    Energy Technology Data Exchange (ETDEWEB)

    Jayakumar, S., E-mail: sjayakumar.physics@gmail.com [Research and Development Centre, Bharathiar University, Coimbatore 641 014 (India); Department of Physics, Pollachi Institute of Engineering and Technology, Pollachi 642 205 (India); Ananthapadmanabhan, P.V.; Thiyagarajan, T.K. [Laser and Plasma Technology Division, BARC, Trombay, Mumbai 400 085 (India); Perumal, K. [Vision for Wisdom, Temple of Consciousness, Aliyar 642 101 (India); Mishra, S.C. [Department of Metallurgical and Materials Engg, National Institute of Technology, Rourkela 769 008 (India); Suresh, G. [Department of Physics, Park College of Engineering and Technology, Coimbatore 641 659 (India); Su, L.T.; Tok, A.I.Y. [School of Materials Science and Engg, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639 798 (Singapore)

    2013-06-15

    Pure zirconium oxide powders with particle size 2–33 nm are synthesized by reactive plasma processing. Transmission electron microscopy investigation of these particles revealed size dependent behavior for their phase stabilization. The monoclinic phase is found to be stable when particle size is ≥20 nm; Tetragonal is found to be stabilized in the range of 7–20 nm and as the particle size decreases to 6 nm and less, the cubic phase is stabilized. - Highlights: ► Direct conversion of micron-sized zirconium hydride powder to single crystal ZrO{sub 2} nanopowder. ► Size dependent stabilization of cubic, tetragonal and monoclinic phases in the reactive plasma synthesized ZrO{sub 2} nanopowder. ► Transmission electron microscopic investigation to identify particles of different sizes and their corresponding phase structure.

  17. Properties of AlN films deposited by reactive ion-plasma sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Bert, N. A.; Bondarev, A. D.; Zolotarev, V. V.; Kirilenko, D. A.; Lubyanskiy, Ya. V.; Lyutetskiy, A. V.; Slipchenko, S. O.; Petrunov, A. N.; Pikhtin, N. A., E-mail: nike@hpld.ioffe.ru; Ayusheva, K. R.; Arsentyev, I. N.; Tarasov, I. S. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

    2015-10-15

    The properties of SiO{sub 2}, Al{sub 2}O{sub 3}, and AlN dielectric coatings deposited by reactive ion-plasma sputtering are studied. The refractive indices of the dielectric coatings are determined by optical ellipsometry. It is shown that aluminum nitride is the optimal material for achieving maximum illumination of the output mirror of a semiconductor laser. A crystalline phase with a hexagonal atomic lattice and oxygen content of up to 10 at % is found by transmission electron microscopy in the aluminum-nitride films. It is found that a decrease in the concentration of residual oxygen in the chamber of the reactive ion-plasma sputtering installation makes it possible to eliminate the appearance of vertical pores in the bulk of the aluminum-nitride film.

  18. Reactive Plasticizers for High Temperature Quinoxaline Thermoplastics

    Science.gov (United States)

    1976-06-01

    involves essentially two steps, consolidation of boardy prepreg into sheet stock and thermoforming the sheet stock into structural components. A...problem associated with the fabrication process is the high temperatures required in both the consolidation and thermoforming operations. High processing

  19. Reactive Spark Plasma Sintering (SPS) of Nitride Reinforced Titanium Alloy Composites (Postprint)

    Science.gov (United States)

    2014-08-15

    ies on in situ alloying and reactions during the SPS process. A recent study on SPS processing of hafnium carbide (HfC) starting from a blend of...AFRL-RX-WP-JA-2014-0177 REACTIVE SPARK PLASMA SINTERING (SPS) OF NITRIDE REINFORCED TITANIUM ALLOY COMPOSITES (POSTPRINT) Jaimie S...SINTERING (SPS) OF NITRIDE REINFORCED TITANIUM ALLOY COMPOSITES (POSTPRINT) 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  20. Baseline Plasma C-Reactive Protein Concentrations and Motor Prognosis in Parkinson Disease.

    Directory of Open Access Journals (Sweden)

    Atsushi Umemura

    Full Text Available C-reactive protein (CRP, a blood inflammatory biomarker, is associated with the development of Alzheimer disease. In animal models of Parkinson disease (PD, systemic inflammatory stimuli can promote neuroinflammation and accelerate dopaminergic neurodegeneration. However, the association between long-term systemic inflammations and neurodegeneration has not been assessed in PD patients.To investigate the longitudinal effects of baseline CRP concentrations on motor prognosis in PD.Retrospective analysis of 375 patients (mean age, 69.3 years; mean PD duration, 6.6 years. Plasma concentrations of high-sensitivity CRP were measured in the absence of infections, and the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III scores were measured at five follow-up intervals (Days 1-90, 91-270, 271-450, 451-630, and 631-900.Change of UPDRS-III scores from baseline to each of the five follow-up periods.Change in UPDRS-III scores was significantly greater in PD patients with CRP concentrations ≥0.7 mg/L than in those with CRP concentrations <0.7 mg/L, as determined by a generalized estimation equation model (P = 0.021 for the entire follow-up period and by a generalized regression model (P = 0.030 for the last follow-up interval (Days 631-900. The regression coefficients of baseline CRP for the two periods were 1.41 (95% confidence interval [CI] 0.21-2.61 and 2.62 (95% CI 0.25-4.98, respectively, after adjusting for sex, age, baseline UPDRS-III score, dementia, and incremental L-dopa equivalent dose.Baseline plasma CRP levels were associated with motor deterioration and predicted motor prognosis in patients with PD. These associations were independent of sex, age, PD severity, dementia, and anti-Parkinsonian agents, suggesting that subclinical systemic inflammations could accelerate neurodegeneration in PD.

  1. PLASMA C-REACTIVE PROTEIN LEVELS AS A PROGNOSTIC MARKER IN FIRST EVER ACUTE ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    Bharat

    2014-12-01

    Full Text Available BACKGROUND AND PURPOSE: Acute ischemic stroke may trigger an inflammatory response that leads to increased levels of C-reactive protein (CRP. High levels of CRP may be associated with poor outcome because they reflect either an inflammatory reaction or tissue damage. We related plasma CRP levels to first ever ischemic stroke and its role as a diagnostic aid. METHODS: Sixty patients fulfilling inclusion and exclusion criteria with first ever acute ischemic stroke were included in study. CT scan of brain was done after 24 hours of onset of symptoms to confirm the diagnosis. Plasma CRP level was determined after 12 hours and before 72 hours of onset of symptoms in all CT confirmed ischemic stroke patients. This clinical study was done from January 2008 to June 2009. CRP was randomly measured in 60 age and sex matched individuals admitted in other wards of the hospital matched in all possible criteria expect the disease under study as a control group. RESULTS: The CRP concentration in ischemic strokes was independent of infarction site, the value was more between 51-70 years of age group and almost equal in both genders. 54 of the 60 ischemic strokes studied had CRP value >6 mg/l and only 6 patients had 6 mg/l, which is insignificant. CONCLUSION: The CRP level is significantly higher in ischemic strokes and by its elevation between 12-72 hours of symptom onset is a bad prognostic indicator. The risk of poor outcome or death at 3 months increased with higher levels of CRP. Elevated CRP values is a risk factor in association with other risk factors like diabetes/hypertension

  2. Non-invasive in situ plasma monitoring of reactive gases using the floating harmonic method for inductively coupled plasma etching application.

    Science.gov (United States)

    Lee, J H; Yoon, Y S; Kim, M J

    2013-04-01

    The floating harmonic method was developed for in situ plasma diagnostics of allowing real time measurement of electron temperature (Te) and ion flux (Jion) without contamination of the probe from surface modification by reactive species. In this study, this novel non-invasive diagnostic system was studied to characterize inductively coupled plasma of reactive gases monitoring Te and Jion for investigating the optimum plasma etching conditions and controlling of the real-time plasma surface reaction in the range of 200-900 W source power, 10-100 W bias power, and 3-15 mTorr chamber pressure, respectively.

  3. Plasma response to transient high voltage pulses

    Indian Academy of Sciences (India)

    S Kar; S Mukherjee

    2013-07-01

    This review reports on plasma response to transient high voltage pulses in a low pressure unmagnetized plasma. Mainly, the experiments are reviewed, when a disc electrode (metallic and dielectric) is biased pulsed negative or positive. The main aim is to review the electron loss in plasmas and particle balance during the negative pulse electrode biasing, when the applied pulse width is less than the ion plasma period. Though the applied pulse width is less than the ion plasma period, ion rarefaction waves are excited. The solitary electron holes are reviewed for positive pulsed bias to the electrode. Also the excitation of waves (solitary electron and ion holes) is reviewed for a metallic electrode covered by a dielectric material. The wave excitation during and after the pulse withdrawal, excitation and propagation characteristics of various electrostatic plasma waves are reviewed here.

  4. Plasma effects in high frequency radiative transfer

    Science.gov (United States)

    Alonso, C. T.

    1981-02-01

    A survey of collective plasma processes which can affect the transfer of high frequency radiation in a hot dense plasma is given. For pedagogical reasons plasma processes are examined by relating them to a particular reference plasma which consists of fully ionized carbon at a temperature kT = 1 KeV (ten million degrees Kelvin) and an electron density N = 3 x 10 to the 23rd power/cu cm, (which corresponds to a mass density rho = 1 gm/cu cm) and an ion density N sub i = 5 x 10 to the 22nd power/cu cm. The transport of photons, ranging from 1 eV to 1 KeV in energy, in such plasmas is considered. Such photons are to be used as diagnostic probes of hot dense laboratory plasmas.

  5. Cancer therapy using non-thermal atmospheric pressure plasma with ultra-high electron density

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Hiromasa [Institute of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Center for Advanced Medicine and Clinical Research, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Mizuno, Masaaki [Center for Advanced Medicine and Clinical Research, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Toyokuni, Shinya [Department of Pathology and Biological Responses, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Maruyama, Shoichi [Department of Nephrology, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Kodera, Yasuhiro [Department of Gastroenterological Surgery (Surgery II), Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Terasaki, Hiroko [Department of Ophthalmology, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Adachi, Tetsuo [Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University, 501-1196 Gifu (Japan); Kato, Masashi [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Kikkawa, Fumitaka [Department of Obstetrics and Gynecology, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550 (Japan); Hori, Masaru [Institute of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

    2015-12-15

    Cancer therapy using non-thermal atmospheric pressure plasma is a big challenge in plasma medicine. Reactive species generated from plasma are key factors for treating cancer cells, and thus, non-thermal atmospheric pressure plasma with high electron density has been developed and applied for cancer treatment. Various cancer cell lines have been treated with plasma, and non-thermal atmospheric plasma clearly has anti-tumor effects. Recent innovative studies suggest that plasma can both directly and indirectly affect cells and tissues, and this observation has widened the range of applications. Thus, cancer therapy using non-thermal atmospheric pressure plasma is promising. Animal experiments and understanding the mode of action are essential for clinical application in the future. A new academic field that combines plasma science, the biology of free radicals, and systems biology will be established.

  6. Cancer therapy using non-thermal atmospheric pressure plasma with ultra-high electron density

    Science.gov (United States)

    Tanaka, Hiromasa; Mizuno, Masaaki; Toyokuni, Shinya; Maruyama, Shoichi; Kodera, Yasuhiro; Terasaki, Hiroko; Adachi, Tetsuo; Kato, Masashi; Kikkawa, Fumitaka; Hori, Masaru

    2015-12-01

    Cancer therapy using non-thermal atmospheric pressure plasma is a big challenge in plasma medicine. Reactive species generated from plasma are key factors for treating cancer cells, and thus, non-thermal atmospheric pressure plasma with high electron density has been developed and applied for cancer treatment. Various cancer cell lines have been treated with plasma, and non-thermal atmospheric plasma clearly has anti-tumor effects. Recent innovative studies suggest that plasma can both directly and indirectly affect cells and tissues, and this observation has widened the range of applications. Thus, cancer therapy using non-thermal atmospheric pressure plasma is promising. Animal experiments and understanding the mode of action are essential for clinical application in the future. A new academic field that combines plasma science, the biology of free radicals, and systems biology will be established.

  7. Production characteristics of reactive oxygen/nitrogen species in water using atmospheric pressure discharge plasmas

    Science.gov (United States)

    Takahashi, Kazuhiro; Satoh, Kohki; Itoh, Hidenori; Kawaguchi, Hideki; Timoshkin, Igor; Given, Martin; MacGregor, Scott

    2016-07-01

    A pulsed discharge, a DC corona discharge, and a plasma jet are separately generated above a water surface, and reactive oxygen species and reactive nitrogen species (ROS/RNS) in the water are investigated. ROS/RNS in water after the sparging of the off-gas of a packed-bed dielectric barrier discharge (PB-DBD) are also investigated. H2O2, NO2 -, and NO3 - are detected after plasma exposure and only NO3 - after off-gas sparging. Short-lifetime species in plasma are found to play an important role in H2O2 and NO2 - production and long-lifetime species in NO3 - production. NO x may inhibit H2O2 production through OH consumption to produce HNO2 and HNO3. O3 does not contribute to ROS/RNS production. The pulsed plasma exposure is found to be effective for the production of H2O2 and NO2 -, and the off-gas sparging of the PB-DBD for the production of NO3 -.

  8. Antenna development for high field plasma imaging.

    Science.gov (United States)

    Kong, X; Domier, C W; Luhmann, N C

    2010-10-01

    Electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry (MIR) are two microwave nonperturbing plasma visualization techniques that employ millimeter-wave imaging arrays with lens-coupled planar antennas, yielding time-resolved images of temperature (via ECEI) and electron density (via MIR) fluctuations within high temperature magnetic fusion plasmas. A series of new planar antennas have been developed that extend this technology to frequencies as high as 220 GHz for use on high field plasma devices with toroidal fields in excess of 3 T. Antenna designs are presented together with theoretical calculations, simulations, and experimental measurements.

  9. Radiation from High Temperature Plasmas.

    Science.gov (United States)

    1980-09-09

    PERFORMING ORGANIZATION NAME AND ADDRESS IO7PUOAM i. .’- "--"--o TASK AREA & WORK UNIT NUMIERS SI I. CONTROLLING OFFICE NAME AND ADDRESS .... D...8217’ -REPORT OATM September 19 14. MONITOING AGENCY NAME & AOORESS(I! dilfl ,rn lm Controlling Office) IS. SECURITY CLASS. (of tli repot) Unclassified 1S...together (specifically 25-50 X, in aluminum) id show comparable intensities is an indicatiou oE a rather substantial temperatura aradient in the plasma

  10. Anxiety-induced plasma norepinephrine augmentation increases reactive oxygen species formation by monocytes in essential hypertension.

    Science.gov (United States)

    Yasunari, Kenichi; Matsui, Tokuzo; Maeda, Kensaku; Nakamura, Munehiro; Watanabe, Takanori; Kiriike, Nobuo

    2006-06-01

    An association between anxiety and depression and increased blood pressure (BP) and cardiovascular disease risk has not been firmly established. We examined the hypothesis that anxiety and depression lead to increased plasma catecholamines and to production of reactive oxygen species (ROS) by mononuclear cells (MNC) in hypertensive individuals. We also studied the role of BP in this effect. In Protocol 1, a cross-sectional study was performed in 146 hypertensive patients to evaluate whether anxiety and depression affect BP and ROS formation by MNC through increasing plasma catecholamines. In Protocol 2, a 6-month randomized controlled trial using a subtherapeutic dose of the alpha(1)-adrenergic receptor antagonist doxazosin (1 mg/day) versus placebo in 86 patients with essential hypertension was performed to determine whether the increase in ROS formation by MNC was independent of BP. In Protocol 1, a significant relationship was observed between the following: trait anxiety and plasma norepinephrine (r = 0.32, P < .01); plasma norepinephrine and ROS formation by MNC (r = 0.36, P < .01); and plasma norepinephrine and systolic, diastolic, and mean BP (r = 0.17, P = .04; r = 0.26, P = .02; r = 0.23, P < .01, respectively). In Protocol 2, subtherapeutic doxazosin treatment (1 mg/day) had no significant effect on BP. However doxazosin significantly decreased ROS formation by MNC compared with placebo (P < .01). Trait anxiety may increase plasma norepinephrine and increase ROS formation by MNC independent of BP in hypertensive patients.

  11. Elevated pre-treatment levels of plasma C-reactive protein are associated with poor prognosis after breast cancer

    DEFF Research Database (Denmark)

    Allin, Kristine H; Nordestgaard, Børge G; Flyger, Henrik;

    2011-01-01

    We examined whether plasma C-reactive protein (CRP) levels at the time of diagnosis of breast cancer are associated with overall survival, disease-free survival, death from breast cancer, and recurrence of breast cancer.......We examined whether plasma C-reactive protein (CRP) levels at the time of diagnosis of breast cancer are associated with overall survival, disease-free survival, death from breast cancer, and recurrence of breast cancer....

  12. A high-efficiency superhydrophobic plasma separator.

    Science.gov (United States)

    Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M; Yang, Shu; Bau, Haim H

    2016-02-01

    To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device's superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a "blood in-plasma out" capability, consistently extracting 65 ± 21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of >84.5 ± 25.8%. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method.

  13. High Power Helicon Plasma Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed work seeks to develop and optimize an electrode-less plasma propulsion system that is based on a high power helicon (HPH) that is being developed...

  14. High Power Helicon Plasma Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new thruster has been conceived and tested that is based on a high power helicon (HPH) plasma wave. In this new method of propulsion, an antenna generates and...

  15. Simvastatin but not bezafibrate decreases plasma lipoprotein-associated phospholipase A(2) mass in type 2 diabetes mellitus : Relevance of high sensitive C-reactive protein, lipoprotein profile and low-density lipoprotein (LDL) electronegativity

    NARCIS (Netherlands)

    Constantinides, Alexander; de Vries, Rindert; van Leeuwen, Jeroen J. J.; Gautier, Thomas; van Pelt, L. Joost; Tselepis, Alexandros D.; Lagrost, Laurent; Dullaart, Robin P. F.

    2012-01-01

    Objective: Plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels predict incident cardiovascular disease, impacting Lp-PLA(2) as an emerging therapeutic target. We determined Lp-PLA(2) responses to statin and fibrate administration in type 2 diabetes mellitus, and assessed relationship

  16. Simvastatin but not bezafibrate decreases plasma lipoprotein-associated phospholipase A(2) mass in type 2 diabetes mellitus : Relevance of high sensitive C-reactive protein, lipoprotein profile and low-density lipoprotein (LDL) electronegativity

    NARCIS (Netherlands)

    Constantinides, Alexander; de Vries, Rindert; van Leeuwen, Jeroen J. J.; Gautier, Thomas; van Pelt, L. Joost; Tselepis, Alexandros D.; Lagrost, Laurent; Dullaart, Robin P. F.

    2012-01-01

    Objective: Plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels predict incident cardiovascular disease, impacting Lp-PLA(2) as an emerging therapeutic target. We determined Lp-PLA(2) responses to statin and fibrate administration in type 2 diabetes mellitus, and assessed

  17. Reactive oxygen species in plasma against E. coli cells survival rate

    Science.gov (United States)

    Zhou, Ren-Wu; Zhang, Xian-Hui; Zong, Zi-Chao; Li, Jun-Xiong; Yang, Zhou-Bin; Liu, Dong-Ping; Yang, Si-Ze

    2015-08-01

    In this paper, we report on the contrastive analysis of inactivation efficiency of E. coli cells in solution with different disinfection methods. Compared with the hydrogen peroxide solution and the ozone gas, the atmospheric-pressure He plasma can completely kill the E. coli cells in the shortest time. The inactivation efficiency of E. coli cells in solution can be well described by using the chemical reaction rate model. X-ray photoelectron spectroscopy (XPS) analysis shows that the C-O or C=O content of the inactivated E. coli cell surface by plasma is predominantly increased, indicating the quantity of oxygen-containing species in plasma is more than those of two other methods, and then the C-C or C-H bonds can be broken, leading to the etching of organic compounds. Analysis also indicates that plasma-generated species can play a crucial role in the inactivation process by their direct reactions or the decompositions of reactive species, such as ozone into OH radicals in water, then reacting with E. coli cells. Project supported by the Natural Science Foundation of Fujian Province, China (Grant No. 2014J01025), the National Natural Science Foundation of China (Grant No. 11275261), and the Funds from the Fujian Provincial Key Laboratory for Plasma and Magnetic Resonance, China.

  18. The Hazards of Reactive Chemicals in High School Laboratories.

    Science.gov (United States)

    Forlin, Peter

    Chemical reactivity is a major area of risk in high school laboratories. This paper reports on a study that has provided a research-based framework for risk management in Australian chemical education. The chemical practice model of risk management is considered with respect to kinetic factors; catalysts; concentrations and proportions;…

  19. Cold atmospheric-pressure air plasma treatment of C6 glioma cells: effects of reactive oxygen species in the medium produced by the plasma on cell death

    Science.gov (United States)

    Wang, Yuyang; Cheng, Cheng; Gao, Peng; Li, Shaopeng; Shen, Jie; Lan, Yan; Yu, Yongqiang; Chu, Paul K.

    2017-02-01

    An atmospheric-pressure air plasma is employed to treat C6 glioma cells in vitro. To elucidate on the mechanism causing cell death and role of reactive species (RS) in the medium produced by the plasma, the concentration of the long-lived RS such as hydrogen peroxide, nitrate, and ozone in the plasma-treated liquid (phosphate-buffered saline solution) is measured. When vitamin C is added to the medium as a ROS quencher, the viability of C6 glioma cells after the plasma treatment is different from that without vitamin C. The results demonstrate that reactive oxygen species (ROS) such as H2O2, and O3 constitute the main factors for inactivation of C6 glioma cells and the reactive nitrogen species (RNS) may only play an auxiliary role in cell death.

  20. Cold atmospheric-pressure air plasma treatment of C6 glioma cells: effects of reactive oxygen species in the medium produced by the plasma on cell death

    Science.gov (United States)

    Yuyang, Wang; Cheng, Cheng; Peng, Gao; Shaopeng, Li; Jie, Shen; Yan, Lan; Yongqiang, Yu; Paul, K. Chu

    2017-02-01

    An atmospheric-pressure air plasma is employed to treat C6 glioma cells in vitro. To elucidate on the mechanism causing cell death and role of reactive species (RS) in the medium produced by the plasma, the concentration of the long-lived RS such as hydrogen peroxide, nitrate, and ozone in the plasma-treated liquid (phosphate-buffered saline solution) is measured. When vitamin C is added to the medium as a ROS quencher, the viability of C6 glioma cells after the plasma treatment is different from that without vitamin C. The results demonstrate that reactive oxygen species (ROS) such as H2O2, and O3 constitute the main factors for inactivation of C6 glioma cells and the reactive nitrogen species (RNS) may only play an auxiliary role in cell death.

  1. Reactivation from latency displays HIV particle budding at plasma membrane, accompanying CD44 upregulation and recruitment

    Directory of Open Access Journals (Sweden)

    Sano Kouichi

    2009-07-01

    Full Text Available Abstract Background It has been accepted that HIV buds from the cell surface in T lymphocytes, whereas in macrophages it buds into intracellular endosomes. Recent studies, on the other hand, suggest that HIV preferentially buds from the cell surface even in monocytic cells. However, most studies are based on observations in acutely infected cells and little is known about HIV budding concomitant with reactivation from latency. Such studies would provide a better understanding of a reservoir for HIV. Results We observed HIV budding in latently infected T lymphocytic and monocytic cell lines following TNF-α stimulation and examined the upregulation of host factors that may be involved in particle production. Electron microscopy analysis revealed that reactivation of latently infected J1.1 cells (latently infected Jurkat cells with HIV-1 and U1 cells (latently infected U937 cells with HIV-1 displayed HIV particle budding predominantly at the plasma membrane, a morphology that is similar to particle budding in acutely infected Jurkat and U937 cells. When mRNA expression levels were quantified by qRT-PCR, we found that particle production from reactivated J1.1 and U1 cells was accompanied by CD44 upregulation. This upregulation was similarly observed when Jurkat and U937 cells were acutely infected with HIV-1 but not when just stimulated with TNF-α, suggesting that CD44 upregulation was linked with HIV production but not with cell stimulation. The molecules in endocytic pathways such as CD63 and HRS were also upregulated when U1 cells were reactivated and U937 cells were acutely infected with HIV-1. Confocal microscopy revealed that these upregulated host molecules were recruited to and accumulated at the sites where mature particles were formed at the plasma membrane. Conclusion Our study indicates that HIV particles are budded at the plasma membrane upon reactivation from latency, a morphology that is similar to particle budding in acute

  2. Enhancement of Limb Growth by Non-Thermal Plasma Generated Reactive Species

    Science.gov (United States)

    Shainsky, N.; Steinbeck, M.; Fridman, G.; Fridman, A.; Friedman, G.; Freeman, T.

    2013-09-01

    Introduction: The goal of this investigation was to examine the effect of Dielectric Barrier Discharge plasma on mouse autopod differentiation and growth. In this study we hypothesized that NT-plasma can be used to promote redox dependent changes in differentiation pathways and enhance developmental signaling? Methods: Approximately 1 hour after isolation, NT-plasma or sham plasma treatment was applied to the right or left limb, respectively. The medium was changed daily thereafter for the 4-6 days of culture. NT-plasma treatment: pulsed (1000 Hz) voltage of 17 - 25 kV magnitude (peak to peak), a 1 μs pulse width and a rise time of 5 V/ns between the quartz-insulated high voltage electrode and the sample undergoing treatment. Results: A single 10 second NT-plasma treatment promoted development of mouse autopods as compared to the sham control contralateral limb. NT-plasma accelerated digit growth in both E14.5 and E12.5 autopods. Inhibitors were used to determine the role of ROS and RNS in mediating NT-plasma accelerated autopod development. Treatment with these agents stunted autopod morphogenesis NT-plasma treatment partially rescued development. Discussion: Our findings highlight the capability of NT-plasma to activate ROS-dependent cell signaling cascades within developing autopod tissue. In fact, the effect of NT-plasma may indeed extend beyond ROS sensitive signaling as NT-plasma exposure seems to stimulate some growth even in the presence of antioxidant induced stunting. This work was supported by NIH Grants 1 R01 EB 013011 - 01 (Freeman and G. Fridman).

  3. Polygenic Overlap Between C-Reactive Protein, Plasma Lipids and Alzheimer's Disease

    Science.gov (United States)

    Desikan, Rahul S.; Thompson, Wesley K.; Dehghan, Abbas; Ridker, Paul M; Chasman, Daniel I.; McEvoy, Linda K.; Holland, Dominic; Chen, Chi-Hua; Karow, David S.; Brewer, James B.; Hess, Christopher P.; Williams, Julie; Sims, Rebecca; O'Donovan, Michael C.; Choi, Seung Hoan; Bis, Joshua C.; Ikram, M. Arfan; Gudnason, Vilmundur; DeStefano, Anita L.; van der Lee, Sven J.; Psaty, Bruce M.; van Duijn, Cornelia M.; Launer, Lenore; Seshadri, Sudha; Pericak-Vance, Margaret A.; Mayeux, Richard; Haines, Jonathan L.; Farrer, Lindsay A.; Hardy, John; Ulstein, Ingun Dina; Aarsland, Dag; Fladby, Tormod; White, Linda R.; Sando, Sigrid B.; Rongve, Arvid; Witoelar, Aree; Djurovic, Srdjan; Hyman, Bradley T.; Snaedal, Jon; Steinberg, Stacy; Stefansson, Hreinn; Stefansson, Kari; Schellenberg, Gerard D.; Andreassen, Ole A.; Dale, Anders M.

    2015-01-01

    Background Epidemiological findings suggest a relationship between Alzheimer's disease (AD), inflammation and dyslipidemia, although the nature of this relationship is not well understood. We investigated whether this phenotypic association arises from a shared genetic basis. Methods and Results Using summary statistics (p-values and odds ratios) from genome-wide association studies of over 200,000 individuals, we investigated overlap in single nucleotide polymorphisms (SNPs) associated with clinically diagnosed AD and C-reactive protein (CRP), triglycerides (TG), high- (HDL) and low-density lipoprotein (LDL) levels. We found up to 50-fold enrichment of AD SNPs for different levels of association with CRP, LDL, HDL and TG SNPs using an FDR threshold < 0.05. By conditioning on polymorphisms associated with the four phenotypes, we identified 55 loci associated with increased AD risk. We then conducted a meta-analysis of these 55 variants across four independent AD cohorts (total n = 29,054 AD cases and 114,824 healthy controls) and discovered two genome-wide significant variants on chromosome 4 (rs13113697, closest gene HS3ST1, odds ratio (OR) = 1.07, 95% confidence interval (CI) = 1.05-1.11, p = 2.86 × 10−8) and chromosome 10 (rs7920721, closest gene ECHDC3, OR = 1.07, 95% CI = 1.04-1.11, p = 3.38 × 10−8). We also found that gene expression of HS3ST1 and ECHDC3 was altered in AD brains compared with control brains. Conclusions We demonstrate genetic overlap between AD, CRP, and plasma lipids. By conditioning on the genetic association with the cardiovascular phenotypes, we identify novel AD susceptibility loci including two genome-wide significant variants conferring increased risk for Alzheimer's disease. PMID:25862742

  4. Nanometer scale high-aspect-ratio trench etching at controllable angles using ballistic reactive ion etching

    Energy Technology Data Exchange (ETDEWEB)

    Cybart, Shane; Roediger, Peter; Ulin-Avila, Erick; Wu, Stephen; Wong, Travis; Dynes, Robert

    2012-11-30

    We demonstrate a low pressure reactive ion etching process capable of patterning nanometer scale angled sidewalls and three dimensional structures in photoresist. At low pressure the plasma has a large dark space region where the etchant ions have very large highly-directional mean free paths. Mounting the sample entirely within this dark space allows for etching at angles relative to the cathode with minimal undercutting, resulting in high-aspect ratio nanometer scale angled features. By reversing the initial angle and performing a second etch we create three-dimensional mask profiles.

  5. Electrospray Ionization Mass Spectrometric Analysis of Highly Reactive Glycosyl Halides

    Directory of Open Access Journals (Sweden)

    Lajos Kovács

    2012-07-01

    Full Text Available Highly reactive glycosyl chlorides and bromides have been analysed by a routine mass spectrometric method using electrospray ionization and lithium salt adduct-forming agents in anhydrous acetonitrile solution, providing salient lithiated molecular ions [M+Li]+, [2M+Li]+ etc. The role of other adduct-forming salts has also been evaluated. The lithium salt method is useful for accurate mass determination of these highly sensitive compounds.

  6. Improvement of Optical Reactivity for Nano-TiO2 Film by Nitrogen ECR Plasma

    Institute of Scientific and Technical Information of China (English)

    Yuying XIONG; Tao MA; Linghong KONG; Junfang CHEN; Xianqiu WU; Honghua YU; Zhenxi ZHANG

    2006-01-01

    Nitrogen ion was implanted into the nano-TiO2 film surfaces by electron cyclotron resonance (ECR) plasma modification to improve the optical reactivity in visible-light region for nano-TiO2. Diagnosing the N2 plasma by optical emission spectroscopy (OES) was applied to the process of plasma modification. X-ray photoelectron spectroscopy (XPS) was used for analysis of the binding of element after plasma modification. It is shown that the surface modification was caused by excitated N. The injecting of N2 and N2+ leads to the increase in the dissociative interstitial state N in the films. The doped N makes for TiO2-xNx appearing in the TiO2films. TiO2-xNx forms the impurity energy state in the TiO2 energy band gap and reduces the energy band gap. This is the main reason leading to the red shift of absorption edge.

  7. Spectroscopy of reactive species produced by low-energy atmospheric-pressure plasma on conductive target material surface

    Science.gov (United States)

    Yamada, Hiromasa; Sakakita, Hajime; Kato, Susumu; Kim, Jaeho; Kiyama, Satoru; Fujiwara, Masanori; Itagaki, Hirotomo; Okazaki, Toshiya; Ikehara, Sanae; Nakanishi, Hayao; Shimizu, Nobuyuki; Ikehara, Yuzuru

    2016-10-01

    A method for blood coagulation using low-energy atmospheric-pressure plasma (LEAPP) is confirmed as an alternative procedure to reduce tissue damage caused by heat. Blood coagulation using LEAPP behaves differently depending on working gas species; helium is more effective than argon in promoting fast coagulation. To analyse the difference in reactive species produced by helium and argon plasma, spectroscopic measurements were conducted without and with a target material. To compare emissions, blood coagulation experiments using LEAPP for both plasmas were performed under almost identical conditions. Although many kinds of reactive species such as hydroxyl radicals and excited nitrogen molecules were observed with similar intensity in both plasmas, intensities of nitrogen ion molecules and nitric oxide molecules were extremely strong in the helium plasma. It is considered that nitrogen ion molecules were mainly produced by penning ionization by helium metastable. Near the target, a significant increase in the emissions of reactive species is observed. There is a possibility that electron acceleration was induced in a local electric field formed on the surface. However, in argon plasma, emissions from nitrogen ion were not measured even near the target surface. These differences between the two plasmas may be producing the difference in blood coagulation behaviour. To control the surrounding gas of the plasma, a gas-component-controllable chamber was assembled. Filling the chamber with O2/He or N2/He gas mixtures selectively produces either reactive oxygen species or reactive nitrogen species. Through selective treatments, this chamber would be useful in studying the effects of specific reactive species on blood coagulation.

  8. Relative reactivity of HIV-1 polyclonal plasma antibodies directed to V3 and MPER regions suggests immunodominance of V3 over MPER and dependence of high anti-V3 antibody titers on virus persistence.

    Science.gov (United States)

    Andrabi, Raiees; Choudhary, Alok K; Bala, Manju; Kalra, Rajesh; Prakash, S S; Pandey, R M; Luthra, Kalpana

    2011-10-01

    Antibodies to two crucial regions, the third variable loop (V3) of gp120 and the membrane-proximal external region (MPER) of gp41 are important for HIV-1 neutralization. We here evaluated the relative binding of polyclonal plasma antibodies from 99 HIV-1-infected individuals from India to the consensus-C V3 and MPER peptides and observed immunodominance of V3 over MPER (p antibody correlates with clinical parameters. Our results revealed that anti-V3 antibody titers are significantly lower in patients on ART compared to drug-naive individuals (p antibodies are dependent on persistence of virus in circulation, while antibodies to MPER are probably not.

  9. Plasma etching of cavities into diamond anvils for experiments at high pressures and high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Weir, S.T.; Cynn, H.; Falabella, S.; Evans, W.J.; Aracne-Ruddle, C.; Farber, D.; Vohra, Y.K. (LLNL); (UAB)

    2012-10-23

    We describe a method for precisely etching small cavities into the culets of diamond anvils for the purpose of providing thermal insulation for samples in experiments at high pressures and high temperatures. The cavities were fabricated using highly directional oxygen plasma to reactively etch into the diamond surface. The lateral extent of the etch was precisely controlled to micron accuracy by etching the diamond through a lithographically fabricated tungsten mask. The performance of the etched cavities in high-temperature experiments in which the samples were either laser heated or electrically heated is discussed.

  10. Fabrication of single-crystal silicon nanotubes with sub-10 nm walls using cryogenic inductively coupled plasma reactive ion etching.

    Science.gov (United States)

    Li, Zhiqin; Chen, Yiqin; Zhu, Xupeng; Zheng, Mengjie; Dong, Fengliang; Chen, Peipei; Xu, Lihua; Chu, Weiguo; Duan, Huigao

    2016-09-09

    Single-crystal silicon nanostructures have attracted much attention in recent years due in part to their unique optical properties. In this work, we demonstrate direct fabrication of single-crystal silicon nanotubes with sub-10 nm walls which show low reflectivity. The fabrication was based on a cryogenic inductively coupled plasma reactive ion etching process using high-resolution hydrogen silsesquioxane nanostructures as the hard mask. Two main etching parameters including substrate low-frequency power and SF6/O2 flow rate ratio were investigated to determine the etching mechanism in the process. With optimized etching parameters, high-aspect-ratio silicon nanotubes with smooth and vertical sub-10 nm walls were fabricated. Compared to commonly-used antireflection silicon nanopillars with the same feature size, the densely packed silicon nanotubes possessed a lower reflectivity, implying possible potential applications of silicon nanotubes in photovoltaics.

  11. Quantum Phenomena in High Energy Density Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, Margaret [Univ. of Colorado, Boulder, CO (United States); Kapteyn, Henry [Univ. of Colorado, Boulder, CO (United States)

    2017-05-10

    The possibility of implementing efficient (phase matched) HHG upconversion of deep- UV lasers in multiply-ionized plasmas, with potentially unprecedented conversion efficiency is a fascinating prospect. HHG results from the extreme nonlinear response of matter to intense laser light:high harmonics are radiated as a result of a quantum coherent electron recollision process that occurs during laser field ionization of an atom. Under current support from this grant in work published in Science in 2015, we discovered a new regime of bright HHG in highly-ionized plasmas driven by intense UV lasers, that generates bright harmonics to photon energies >280eV

  12. Relative reactivities of N-chloramines and hypochlorous acid with human plasma constituents.

    Science.gov (United States)

    Carr, A C; Hawkins, C L; Thomas, S R; Stocker, R; Frei, B

    2001-03-01

    Hypochlorous acid (HOCl), the major strong oxidant produced by the phagocyte enzyme myeloperoxidase, reacts readily with free amino groups to form N-chloramines. Since different N-chloramines have different stabilities and reactivities depending on their structures, we investigated the relative reactivities of three model N-chloramines and HOCl with human plasma constituents. TheN-chloramines studied were N(alpha)-acetyl-lysine chloramine (LysCA, a model of protein-associated N-chloramines), taurine chloramine (TaurCA, the primary N-chloramine produced by activated neutrophils), and monochloramine (MonoCA, a lipophilic N-chloramine). Addition of these chlorine species (100--1000 microM each) to plasma resulted in rapid loss of thiols, with the extent of thiol oxidation decreasing in the order TaurCA = LysCA > MonoCA = HOCl. The single reduced thiol of albumin was the major target. Loss of plasma ascorbate also occurred, with the extent decreasing in the order HOCl > LysCA > TaurCA > MonoCA. Experiments comparing equimolar albumin thiols and ascorbate showed that while HOCl caused equivalent loss of thiols and ascorbate, theN-chloramines reacted preferentially with thiols. The chlorine species also inactivated alpha(1)-antiproteinase, implicating oxidation of methionine residues, and ascorbate provided variable protection depending on the chlorine species involved. Together, our data indicate that in biological fluids N-chloramines react more readily with protein thiols than with methionine residues or ascorbate, and thus may cause biologically relevant, selective loss of thiol groups.

  13. In Situ Fabrication of AlN Coating by Reactive Plasma Spraying of Al/AlN Powder

    Directory of Open Access Journals (Sweden)

    Mohammed Shahien

    2011-10-01

    Full Text Available Reactive plasma spraying is a promising technology for the in situ formation of aluminum nitride (AlN coatings. Recently, it became possible to fabricate cubic-AlN-(c-AlN based coatings through reactive plasma spraying of Al powder in an ambient atmosphere. However, it was difficult to fabricate a coating with high AlN content and suitable thickness due to the coalescence of the Al particles. In this study, the influence of using AlN additive (h-AlN to increase the AlN content of the coating and improve the reaction process was investigated. The simple mixing of Al and AlN powders was not suitable for fabricating AlN coatings through reactive plasma spraying. However, it was possible to prepare a homogenously mixed, agglomerated and dispersed Al/AlN mixture (which enabled in-flight interaction between the powder and the surrounding plasma by wet-mixing in a planetary mill. Increasing the AlN content in the mixture prevented coalescence and increased the nitride content gradually. Using 30 to 40 wt% AlN was sufficient to fabricate a thick (more than 200 µm AlN coating with high hardness (approximately 1000 Hv. The AlN additive prevented the coalescence of Al metal and enhanced post-deposition nitriding through N2 plasma irradiation by allowing the nitriding species in the plasma to impinge on a larger Al surface area. Using AlN as a feedstock additive was found to be a suitable method for fabricating AlN coatings by reactive plasma spraying. Moreover, the fabricated coatings consist of hexagonal (h-AlN, c-AlN (rock-salt and zinc-blend phases and certain oxides: aluminum oxynitride (Al5O6N, cubic sphalerite Al23O27N5 (ALON and Al2O3. The zinc-blend c-AlN and ALON phases were attributed to the transformation of the h-AlN feedstock during the reactive plasma spraying. Thus, the zinc-blend c

  14. Synthetic peptides and fluorogenic substrates related to the reactive site sequence of Kunitz-type inhibitors isolated from Bauhinia: interaction with human plasma kallikrein.

    Science.gov (United States)

    Oliva, M L; Santomauro-Vaz, E M; Andrade, S A; Juliano, M A; Pott, V J; Sampaio, M U; Sampaio, C A

    2001-01-01

    We have previously described Kunitz-type serine proteinase inhibitors purified from Bauhinia seeds. Human plasma kallikrein shows different susceptibility to those inhibitors. In this communication, we describe the interaction of human plasma kallikrein with fluorogenic and non-fluorogenic peptides based on the Bauhinia inhibitors' reactive site. The hydrolysis of the substrate based on the B. variegata inhibitor reactive site sequence, Abz-VVISALPRSVFIQ-EDDnp (Km 1.42 microM, kcat 0.06 s(-1), and kcat/Km 4.23 x 10(4) M(-1) s(-1)), is more favorable than that of Abz-VMIAALPRTMFIQ-EDDnp, related to the B. ungulata sequence (Km 0.43 microM, kcat 0.00017 s(-1), and kcat/Km 3.9 x 10(2) M(-1) s(-1)). Human plasma kallikrein does not hydrolyze the substrates Abz-RPGLPVRFESPL-EDDnp and Abz-FESPLRINIIKE-EDDnp based on the B. bauhinioides inhibitor reactive site sequence, the most effective inhibitor of the enzyme. These peptides are competitive inhibitors with Ki values in the nM range. The synthetic peptide containing 19 amino acids based on the B. bauhinioides inhibitor reactive site (RPGLPVRFESPL) is poorly cleaved by kallikrein. The given substrates are highly specific for trypsin and chymotrypsin hydrolysis. Other serine proteinases such as factor Xa, factor XII, thrombin and plasmin do not hydrolyze B. bauhinioides inhibitor related substrates.

  15. Signature biochemical properties of broadly cross-reactive HIV-1 neutralizing antibodies in human plasma.

    Science.gov (United States)

    Sajadi, Mohammad M; Lewis, George K; Seaman, Michael S; Guan, Yongjun; Redfield, Robert R; DeVico, Anthony L

    2012-05-01

    The common properties of broadly cross-reactive HIV-1 neutralization antibodies found in certain HIV-1-infected individuals holds significant value for understanding natural and vaccine-mediated anti-HIV immunity. Recent efforts have addressed this question by deriving neutralizing monoclonal anti-envelope antibodies from memory B cell pools of selected subjects. However, it has been more difficult to identify whether broadly neutralizing antibodies circulating in plasma possess shared characteristics among individuals. To address this question, we used affinity chromatography and isoelectric focusing to fractionate plasma immunoglobulin from 10 HIV-1-infected subjects (5 subjects with broad HIV-1 neutralizing activity and 5 controls). We find that plasma neutralizing activity typically partitions into at least two subsets of antibodies. Antibodies with restricted neutralization breadth have relatively neutral isoelectric points and preferentially bind to envelope monomers and trimers versus core antigens from which variable loops and other domains have been deleted. In comparison, broadly neutralizing antibodies account for a minor fraction of the total anti-envelope response. They are consistently distinguished by more basic isoelectric points and specificity for epitopes shared by monomeric gp120, gp120 core, or CD4-induced structures. Such biochemical properties might be exploited to reliably predict or produce broad anti-HIV immunity.

  16. Physics of High Temperature, Dense Plasmas.

    Science.gov (United States)

    1984-01-01

    34Investigation of the High-Energy Acceleration Mode in the Coaxial Gun," Phys. Fluids, Suppl., S28, (1964). I. 9. Dattner, A. and Eninger J...34Studies of a Coaxial Plasma Gun," Phys. Fluids, Suppl., S41, (1964). II. 10. Wilcox, J. M., Pugh, E., Dattner, A. and Eninger , J., "Experimental Study of

  17. Relationship between high-sensitivity C-reactive protein level and angiographical characteristics of coronary atherosclerosis

    Institute of Scientific and Technical Information of China (English)

    JIA En-zhi; HUANG Jun; MA Wen-zhu; YANG Zhi-jian; YUAN Biao; ZANG Xiao-ling; WANG Rong-hu; ZHU Tie-bing; WANG Lian-sheng; CHEN Bo; CAO Ke-jiang

    2006-01-01

    @@ Arole for inflammation has become well established over the past decade or more in theories describing the atherosclerotic disease process.1,2 From a pathological viewpoint, all stages, ie, initiation, growth, and complication of the atherosclerotic plaque,3,4 might be considered to be an inflammatory response to injury. Several prospective studies 5-7 recently showed that plasma high sensitivity C-reactive protein (hsCRP) levels, which are one of the markers of systemic inflammation, are a powerful predictor of future myocardial infarction and cardiac death among apparently healthy individuals. However, the association between the plasma hsCRP levels and the extent of coronary stenosis in subjects remains controversial. Some studies previously demon- strated such associations,8,9 whereas other could not found.10,11 Gensini's score assigns a severity score for a stenosed vessel depending on the degree of luminal narrowing and the importance of its location.12

  18. Atmospheric pressure plasma: a high-performance tool for the efficient removal of biofilms.

    Directory of Open Access Journals (Sweden)

    Katja Fricke

    Full Text Available INTRODUCTION: The medical use of non-thermal physical plasmas is intensively investigated for sterilization and surface modification of biomedical materials. A further promising application is the removal or etching of organic substances, e.g., biofilms, from surfaces, because remnants of biofilms after conventional cleaning procedures are capable to entertain inflammatory processes in the adjacent tissues. In general, contamination of surfaces by micro-organisms is a major source of problems in health care. Especially biofilms are the most common type of microbial growth in the human body and therefore, the complete removal of pathogens is mandatory for the prevention of inflammatory infiltrate. Physical plasmas offer a huge potential to inactivate micro-organisms and to remove organic materials through plasma-generated highly reactive agents. METHOD: In this study a Candida albicans biofilm, formed on polystyrene (PS wafers, as a prototypic biofilm was used to verify the etching capability of the atmospheric pressure plasma jet operating with two different process gases (argon and argon/oxygen mixture. The capability of plasma-assisted biofilm removal was assessed by microscopic imaging. RESULTS: The Candida albicans biofilm, with a thickness of 10 to 20 µm, was removed within 300 s plasma treatment when oxygen was added to the argon gas discharge, whereas argon plasma alone was practically not sufficient in biofilm removal. The impact of plasma etching on biofilms is localized due to the limited presence of reactive plasma species validated by optical emission spectroscopy.

  19. Conclusive evidence of abrupt coagulation inside the void during cyclic nanoparticle formation in reactive plasma

    Science.gov (United States)

    van de Wetering, F. M. J. H.; Nijdam, S.; Beckers, J.

    2016-07-01

    In this letter, we present scanning electron microscopy (SEM) results that confirm in a direct way our earlier explanation of an abrupt coagulation event as the cause for the void hiccup. In a recent paper, we reported on the fast and interrupted expansion of voids in a reactive dusty argon-acetylene plasma. The voids appeared one after the other, each showing a peculiar, though reproducible, behavior of successive periods of fast expansion, abrupt contraction, and continued expansion. The abrupt contraction was termed "hiccup" and was related to collective coagulation of a new generation of nanoparticles growing in the void using relatively indirect methods: electron density measurements and optical emission spectroscopy. In this letter, we present conclusive evidence using SEM of particles collected at different moments in time spanning several growth cycles, which enables us to follow the nanoparticle formation process in great detail.

  20. Reactive radical-driven bacterial inactivation by hydrogen-peroxide-enhanced plasma-activated-water

    Science.gov (United States)

    Wu, Songjie; Zhang, Qian; Ma, Ruonan; Yu, Shuang; Wang, Kaile; Zhang, Jue; Fang, Jing

    2017-08-01

    The combined effects of plasma activated water (PAW) and hydrogen peroxide (H2O2), PAW/HP, in sterilization were investigated in this study. To assess the synergistic effects of PAW/HP, S. aureus was selected as the test microorganism to determine the inactivation efficacy. Also, the DNA/RNA and proteins released by the bacterial suspensions under different conditions were examined to confirm membrane integrity. Additionally, the intracellular pH (pHi) of S. aureus was measured in our study. Electron spin resonance spectroscopy (ESR) was employed to identify the presence of radicals. Finally, the oxidation reduction potential (ORP), conductivity and pH were measured. Our results revealed that the inactivation efficacy of PAW/HP is much greater than that of PAW, while increased H2O2 concentration result in higher inactivation potential. More importantly, as compared with PAW, the much stronger intensity ESR signals and higher ORP in PAW/HP suggests that the inactivation mechanism of the synergistic effects of PAW/HP: more reactive oxygen species (ROS) and reactive nitrogen species (RNS), especially OH and NO radicals, are generated in PAW combined with H2O2 resulting in more deaths of the bacteria.

  1. RELATION BETWEEN DIETARY INTAKE AND PLASMA HIGH SENSITIVE C-REACTIVE PROTEIN LEVEL IN 40-65 YEARS OLD ADULTS IN GUANGZHOU%广州市40~65岁居民膳食因素与血浆高敏C反应蛋白水平的相关关系分析

    Institute of Scientific and Technical Information of China (English)

    马丽萍; 许颖; 张波; 苏宜香

    2015-01-01

    目的:探讨膳食因素与血浆高敏C反应蛋白(hsCRP)水平的关系。方法以志愿者的形式招募广州市40~65岁居民,采用膳食频数问卷法(FFQ)调查研究对象的膳食摄入情况,并用免疫比浊散射法检测其血浆 hsCRP的水平。结果共招募553名志愿者,血浆hsCRP值为(1.56±2.19) mg/L。校正了年龄、教育程度、吸烟、饮酒、BMI、能量摄入等混杂因素的偏相关分析显示,女性的蔬菜、水果摄入量与 hsCRP 水平负相关(P<0.05),总体研究对象碳水化合物、膳食纤维的摄入量与hsCRP负相关(P<0.05),在男性中膳食纤维的相关关系显著(P<0.05)。根据血浆hsCRP水平<1 mg/L、1~3 mg/L、≥3 mg/L预测可能发生心血管疾病(CVD)的低、中、高风险,在校正了年龄、性别、BMI等混杂因素后,Logistic回归分析显示:随着水果摄入量、膳食纤维摄入量的减少、研究对象将来发生高hsCRP的风险增加(P<0.05);以最高摄入量Q4组为对照,水果摄入量Q3组、膳食纤维摄入量Q2组、脂肪供能比Q1组、饱和脂肪酸供能比Q2组是Q4组将来发生高hsCRP的风险的1.69、1.71、0.42、0.41倍(OR值)(P<0.05)。结论增加膳食中蔬菜、水果、碳水化合物、膳食纤维的摄入可降低血浆hsCRP水平,增加水果和膳食纤维摄入量、控制膳食总脂肪供能比、降低饱和脂肪供能比可能会降低心血管疾病发生的风险。[营养学报,2015,37(4):335-340]%Objective To investigate the relationship between dietary intake and plasma high-sensitive C-reactive protein (hsCRP) level.Methods 40-65 years old residents in Guangzhou were enrolled. Dietary food and nutrient intakes were assessed by quantitative food frequency questionnaire (FFQ). Plasma hsCRP level were detected by immunoturbidimetry. Results 553 residents were enrolled. HsCRP level in plasma was (1.56±2.19) mg/L. After adjusted for age

  2. High-Gain High-Field Fusion Plasma

    Science.gov (United States)

    Li, Ge

    2015-01-01

    A Faraday wheel (FW)—an electric generator of constant electrical polarity that produces huge currents—could be implemented in an existing tokamak to study high-gain high-field (HGHF) fusion plasma, such as the Experimental Advanced Superconducting Tokamak (EAST). HGHF plasma can be realized in EAST by updating its pulsed-power system to compress plasma in two steps by induction fields; high gains of the Lawson trinity parameter and fusion power are both predicted by formulating the HGHF plasma. Both gain rates are faster than the decrease rate of the plasma volume. The formulation is checked by earlier ATC tests. Good agreement between theory and tests indicates that scaling to over 10 T at EAST may be possible by two-step compressions with a compression ratio of the minor radius of up to 3. These results point to a quick new path of fusion plasma study, i.e., simulating the Sun by EAST. PMID:26507314

  3. SU-8 photolithography on reactive plasma thin-films: coated microwells for peptide display.

    Science.gov (United States)

    Marchesan, Silvia; Easton, Christopher D; Styan, Katie E; Leech, Patrick; Gengenbach, Thomas R; Forsythe, John S; Hartley, Patrick G

    2013-08-01

    We have developed a technique to create 50μm-deep microwells coated with a reactive and robust thin film, which withstands photolithographic processing, and allows for subsequent chemical functionalisation with biological cues (i.e. peptides). First, plasma polymerisation of 1-bromopropane was used to generate a bromine-functionalised thin film (BrPP) on a substrate of silicon wafer. Second, an epoxy functionalised polymer UV photoresist, SU-8, was deposited and developed to create 50μm-deep patterned microwells that display the BrPP coating at their base. Third, amino acids or peptides were selectively attached to the bottom of the microwells through bromine displacement by an amine or thiol nucleophile. Each surface functionalisation step was monitored by XPS, AFM, and contact angle measurements. These functionalities were then used as linkers to immobilise enzymes (e.g. HRP), which retain activity at the end of the process as shown by a biochemical activity assay. Peptide promoters of cell attachment were also immobilised and their functionality was evaluated using an L929 fibroblast adhesion assay. In conclusion, this work describes an innovative combination of plasma thin film deposition and photolithography to create 50μm-deep functionalised microwells for peptide display in biological applications.

  4. Effect of taurine and caffeine on plasma c-reactive protein and calcium in Wistar rats.

    Science.gov (United States)

    Owoyele, B V; Oyewole, A L; Biliaminu, S A; Alashi, Y

    2015-09-01

    Caffeine is a component of several beverages such as coffee and tea. It has been shown to possess psychoactive properties because it increases alertness, energy and ability to concentrate at moderate doses. Taurine on the other hand, is an amino acid which has the capacity to promote neural development, osmoregulation and neuroprotection. There is paucity of information on the effect of the combined administration of taurine and caffeine on C-reactive protein (CRP)--a marker of inflammation and plasma calcium level in rats. The present study was designed to investigate the effects of combined taurine and caffeine on the plasma level of CRP, Ca2+ as well as the effect of nifedipine on calcium level. Fifty four rats weighing 120-140 g were used for these studies. The animals were divided into nine groups consisting of six animals each. Group 1 was treated with 10 m/kg of normal saline, Groups 2 and 3 were given 100 mg/kg and 200 mg/kg of taurine respectively, groups 4 and 5 received 7.5 mg/kg and 15 mg/kg of caffeine respectively while group 6 was administered taurine (200 mg/kg) and caffeine (15 mg/kg), groups 7 and 8 were treated with taurine (200 mg/kg) plus nifedipine (10 mg/kg) and taurine (200 mg/kg)plus furosemide (20 mg/kg) respectively while group 9 was given taurine plu caffeine plus nifdipine plus furosemide. Treatment was done once daily for 21 days and blood was finally collected via cardiac puncture for the assay of CRP and calcium while the animals were under anaesthesia. The results showed that CRP was significantly decreased in five of the treated groups compared with the control with the exception of the group treated with taurine alone (Group 2), and that treated with combined taurine and caffeine (Group 6). The Ca2+ level of groups treated with caffeine (11.70 ± 0.29 mg/dL) and taurine with caffeine (11.64 ± 0.15 mg/dL) were significantly (p taurine and nifedipine (Group 7) led to significant (p taurine can boost plasma calcium level and

  5. Evaluation of plasma reactive oxygen metabolites levels in obese subjects with periodontal disease

    Directory of Open Access Journals (Sweden)

    Snophia Suresh

    2016-01-01

    Result and Conclusion: In this study, obese subjects with chronic periodontitis (Group I had mean plasma ROM levels (442.3 ± 15.65 Carratelli unit [CARR U] showing 100% subjects with high oxidative stress. Obese subjects with chronic gingivitis (Group II had mean plasma ROM levels (358.7 ± 20.61 CARR U indicating 86.7% subjects with oxidative stress. Obese subjects with healthy periodontium (Group III had 46.7% subjects with slight oxidative stress, and the mean ROM level was 320.2 ± 17.57. Nonobese subjects with healthy periodontium (Group IV had 80% of subjects with normal oxidative stress and the mean plasma ROM level was 296.9 ± 20.35 CARR U. The intra- and inter-group comparison showed significant difference (P < 0.001. From our study, we report that obese subjects with periodontitis have more oxidative stress compared to obese subjects with healthy periodontium.

  6. Helium-based cold atmospheric plasma-induced reactive oxygen species-mediated apoptotic pathway attenuated by platinum nanoparticles.

    Science.gov (United States)

    Jawaid, Paras; Rehman, Mati Ur; Zhao, Qing Li; Takeda, Keigo; Ishikawa, Kenji; Hori, Masaru; Shimizu, Tadamichi; Kondo, Takashi

    2016-09-01

    Plasma is generated by ionizing gas molecules. Helium (He)-based cold atmospheric plasma (CAP) was generated using a high-voltage power supply with low-frequency excitation (60 Hz at 7 kV) and He flow at 2 l/min. Platinum nanoparticles (Pt-NPs) are potent antioxidants due to their unique ability to scavenge superoxides and peroxides. These features make them useful for the protection against oxidative stress-associated pathologies. Here, the effects of Pt-NPs on He-CAP-induced apoptosis and the underlying mechanism were examined in human lymphoma U937 cells. Apoptosis was measured after cells were exposed to He-CAP in the presence or absence of Pt-NPs. The effects of combined treatment were determined by observing the changes in intracellular reactive oxygen species (ROS) and both mitochondrial and Fas dependent pathway. The results indicate that Pt-NPs substantially scavenge He-CAP-induced superoxides and peroxides and inhibit all the pathways involved in apoptosis execution. This might be because of the SOD/catalase mimetic effects of Pt-NPs. These results showed that the Pt-NPs can induce He-CAP desensitization in human lymphoma U937 cells.

  7. Laser Plasma Coupling for High Temperature Hohlraums

    Energy Technology Data Exchange (ETDEWEB)

    Kruer, W.

    1999-11-04

    Simple scaling models indicate that quite high radiation temperatures can be achieved in hohlraums driven with the National Ignition Facility. A scaling estimate for the radiation temperature versus pulse duration for different size NIF hohlraums is shown in Figure 1. Note that a radiation temperature of about 650 ev is projected for a so-called scale 1 hohlraum (length 2.6mm, diameter 1.6mm). With such high temperature hohlraums, for example, opacity experiments could be carried out using more relevant high Z materials rather than low Z surrogates. These projections of high temperature hohlraums are uncertain, since the scaling model does not allow for the very strongly-driven laser plasma coupling physics. Lasnex calculations have been carried out to estimate the plasma and irradiation conditions in a scale 1 hohlraum driven by NIF. Linear instability gains as high as exp(100) have been found for stimulated Brillouin scattering, and other laser-driven instabilities are also far above their thresholds. More understanding of the very strongly-driven coupling physics is clearly needed in order to more realistically assess and improve the prospects for high temperature hohlraums. Not surprisingly, this regime has been avoided for inertial fusion applications and so is relatively unexplored.

  8. A global plasma model for reactive deposition of compound films by modulated pulsed power magnetron sputtering discharges

    Science.gov (United States)

    Zheng, B. C.; Wu, Z. L.; Wu, B.; Li, Y. G.; Lei, M. K.

    2017-05-01

    A spatially averaged, time-dependent global plasma model has been developed to describe the reactive deposition of a TiAlSiN thin film by modulated pulsed power magnetron sputtering (MPPMS) discharges in Ar/N2 mixture gas, based on the particle balance and the energy balance in the ionization region, and considering the formation and erosion of the compound at the target surface. The modeling results show that, with increasing the N2 partial pressure from 0% to 40% at a constant working pressure of 0.3 Pa, the electron temperature during the strongly ionized period increases from 4 to 7 eV and the effective power transfer coefficient, which represents the power fraction that effectively heats the electrons and maintains the discharge, increases from about 4% to 7%; with increasing the working pressure from 0.1 to 0.7 Pa at a constant N2 partial pressure of 25%, the electron temperature decreases from 10 to 4 eV and the effective power transfer coefficient decreases from 8% to 5%. Using the modeled plasma parameters to evaluate the kinetic energy of arriving ions, the ion-to-neutral flux ratio of deposited species, and the substrate heating, the variations of process parameters that increase these values lead to an enhanced adatom mobility at the target surface and an increased input energy to the substrate, corresponding to the experimental observation of surface roughness reduction, the microstructure transition from the columnar structure to the dense featureless structure, and the enhancement of phase separation. At higher N2 partial pressure or lower working pressure, the modeling results demonstrate an increase in electron temperature, which shifts the discharge balance of Ti species from Ti+ to Ti2+ and results in a higher return fraction of Ti species, corresponding to the higher Al/Ti ratio of deposited films at these conditions. The modeling results are well correlated with the experimental observation of the composition variation and the microstructure

  9. Modelisation de la synthese reactive de poudres ultrafines dans un reacteur a plasma thermique

    Science.gov (United States)

    Desilets, Martin

    La presente these s'inscrit dans le cadre de la modelisation mathematique des ecoulements a plasmas thermiques inertes et reactifs. Elle vise plus precisement a combler les lacunes des modeles existants en portant une attention particuliere aux phenomenes de transport multicomposant et a la prediction des transformations chimiques. Pour repondre a ces attentes et ainsi poursuivre le developpement dans ce domaine, un modele global a ete developpe. Il combine la resolution d'equations conservatives pour la masse, l'energie et le momentum. La generation d'un plasma inductif (h.f ) y est traitee au moyen d'equations representant les champs electromagnetiques. La nucleation et la croissance de poudres ultrafines sont incluses dans le modele via l'analyse des principaux moments de la distribution des tailles de particules. Enfin, tous les phenomenes physico-chimiques d'importance dans un milieu comme les plasmas thermiques, de meme que lem interactions, sont consideres. Le modele est applique ici a l'analyse de trois problematiques differentes et complementaires. La premiere concerne l'etude du melange gazeux d'un jet froid (He, N 2 ou O2), injecte au coeur d'une decharge d'argon/hydrogene ou d'argon/oxygene. La comparaison des predictions du modele avec des mesures experimentales obtenues par une sonde enthalpique permet une validation partielle de ce dernier. La deuxieme problematique a trait a l'etude numerique de la pyrolyse du methane en reacteur a plasma h.f. Elle met en evidence les difficultes de convergence de la methode numerique lorsque appliquee a la resolution d'ecoulements reactifs a haute temperature. Finalement, le dernier sujet aborde dans cette these, soit l'analyse systematique des principales conditions d'operation d'un reacteur h.f utilise pour la synthese reactive de poudres ultrafines de silicium, engage tous les elements theoriques du modele. Il implique en effet la decomposition thermique d'un precurseur gazeux, le tetrachlorure de silicium, la

  10. Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, Venereal Disease Research Laboratory, and rapid plasma reagin tests in primary syphilis.

    Science.gov (United States)

    Huber, T W; Storms, S; Young, P; Phillips, L E; Rogers, T E; Moore, D G; Williams, R P

    1983-03-01

    Seroreactivity of sera from 109 patients with first-infection primary syphilis was 98.2% in the fluorescent treponemal antibody absorption test, 92.7% in the rapid plasma reagin 18-mm circle card test, 72.5% in the microhemagglutination test (MHA-TP), and 72.5% in the Venereal Disease Research Laboratory test. Seroreactivity of sera from 18 patients with primary syphilis with documented previous infection(s) was 100% in the fluorescent treponemal antibody absorption test, the rapid plasma reagin 18-mm circle card test, and the MHA-TP test and 88.9% in the Venereal Disease Research Laboratory test. The MHA-TP test failed to confirm reactivity in 13 of 79 sera which were reactive in the Venereal Disease Research Laboratory test and in 24 of 101 sera which were reactive in the rapid plasma reagin 18-mm circle card test. Testing another production lot of MHA-TP reagents resulted in even poorer correlation. The reactivity of the MHA-TP test in primary syphilis appeared to vary with the sensitivity of the production lot of reagents.

  11. STUDY ON HIGH ACID LEACHING REACTIVE CALCINED KAOLIN

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Leaching experiments on metakaolin show that the final Al extraction ratio reached in a batch reaction is strikingly influenced by the inferior pore structure geometry of the metakaolin pellets. By calcining kaolin particles adhered in low humidity state,a variety of metakaolin pellet,inside which a large openings structure developed,has been prepared. The structure remarkably benefits leachant ion transference,so,the variety has high acid leaching reactivity,even coarse as the pellets are,its aluminum extracted ratio still has a linear relationship with leaching time,and the leaching kinetics is maintained zero order up to a significant conversion degree. A revised Pellet-Particle Model has been developed to interpret the structure influence on Al extraction ratio.

  12. The removal of reactive dyes using high-ash char

    Directory of Open Access Journals (Sweden)

    Moreira R.F.P.M.

    2001-01-01

    Full Text Available The thermodynamics and kinetics of adsorption of reactive dyes on high-ash char was studied. Equilibrium data were obtained using the static method with controlled agitation at temperatures in the range of 30 to 60ºC. The Langmuir isotherm model was used to describe the equilibrium of adsorption, and the equilibrium parameters, R L, in the range of 0 to 1 indicate favorable adsorption. The amount of dye adsorbed increased as temperature increased from 30 to 40ºC, but above 40ºC the increase in temperature resulted in a decrease in the amount of dye adsorbed. The kinetic data presented are for controlled agitation at 50 rpm and constant temperature with dye concentrations in the range of 10 ppm to50 ppm. The film mass transfer coefficient, Kf, and the effective diffusivity inside the particle, De, were fitted to the experimental data. The results indicate that internal diffusion governs the adsorption rate.

  13. Highly reactive free radicals in electronic cigarette aerosols.

    Science.gov (United States)

    Goel, Reema; Durand, Erwann; Trushin, Neil; Prokopczyk, Bogdan; Foulds, Jonathan; Elias, Ryan J; Richie, John P

    2015-09-21

    Electronic cigarette (EC) usage has increased exponentially, but limited data are available on its potential harmful effects. We tested for the presence of reactive, short-lived free radicals in EC aerosols by electron paramagnetic resonance spectroscopy (EPR) using the spin-trap phenyl-N-tert-butylnitrone (PBN). Radicals were detected in aerosols from all ECs and eliquids tested (2.5 × 10(13) to 10.3 × 10(13) radicals per puff at 3.3 V) and from eliquid solvents propylene glycol and glycerol and from "dry puffing". These results demonstrate, for the first time, the production of highly oxidizing free radicals from ECs which may present a potential toxicological risk to EC users.

  14. Preparation and Microstructure of Porous ZrB2 Ceramics Using Reactive Spark Plasma Sintering Method

    Institute of Scientific and Technical Information of China (English)

    YUAN Huiping; LI Junguo; SHEN Qiang; ZHANG Lianmeng

    2015-01-01

    Zirconium oxide (ZrO2) and boron carbide (B4C) were added to ZrB2 raw powders to prepare ZrB2 porous ceramics by reactive spark plasma sintering (RSPS). The reactions between ZrO2 and B4C which produce ZrB2 and gas (such as CO and B2O3) result in pore formation. X-Ray Diffraction results indicated that the products phase was ZrB2 and the reaction was completed after the RSPS process. The porosity could be controlled by changing the ratio of synthesized ZrB2 to raw ZrB2 powders. The porosity of porous ceramics with 20 wt% and 40 wt% synthsized ZrB2 are 0.185 and 0.222, respectivly. And dense ZrB2-SiC ceramic with a porosity of 0.057 was prepared under the same conditions for comparison. The pores were homogeneously distributed within the microstructure of the porous ceramics. The results indicate a promising method for preparing porous ZrB2-based ceramics.

  15. Evolution of sputtering target surface composition in reactive high power impulse magnetron sputtering

    Science.gov (United States)

    Kubart, T.; Aijaz, A.

    2017-05-01

    The interaction between pulsed plasmas and surfaces undergoing chemical changes complicates physics of reactive High Power Impulse Magnetron Sputtering (HiPIMS). In this study, we determine the dynamics of formation and removal of a compound on a titanium surface from the evolution of discharge characteristics in an argon atmosphere with nitrogen and oxygen. We show that the time response of a reactive process is dominated by surface processes. The thickness of the compound layer is several nm and its removal by sputtering requires ion fluence in the order of 1016 cm-2, much larger than the ion fluence in a single HiPIMS pulse. Formation of the nitride or oxide layer is significantly slower in HiPIMS than in dc sputtering under identical conditions. Further, we explain very high discharge currents in HiPIMS by the formation of a truly stoichiometric compound during the discharge off-time. The compound has a very high secondary electron emission coefficient and leads to a large increase in the discharge current upon target poisoning.

  16. The value of measuring plasma oxidized low-density lipoprotein and serum high sensitivity C-reactive protein in patients with acute coronary syndrome%急性冠脉综合征患者测定血浆氧化低密度脂蛋白和血清高敏C-反应蛋白的价值

    Institute of Scientific and Technical Information of China (English)

    魏艳胜; 张晓

    2008-01-01

    Objective To investigate the value of plasma oxidized low-density lipoprotein(ox-LDL)and serum high sensitivity C-reactive protein(hs-CRP)in patients with acute coronary syndrome(ACS).Methods Plasma ox-LDL and serum hs-CRP levels were measured by enzyme-linked immunosorbent assav in 89 patients,who were divided into 4 groups:acute myocardial infarction,stable angina pectoris,unstable angina pectoris and control.Results The ox-LDL and hs-CRP levels were higher in the acute coronary syndrome patients than in the controls and stable angina peetoris(P<0.0 1).Significant positive corrlelation between ox-LDL and hs - CRP was fbund in patients with coronary artery disease(CAD)(r=0.801,P<0.01).but no eorrelation in the controls(r=0.084,P>0.05).No correlation was found between ox-LDL and Gensini score in the CAD group(r=-0.051,P>0.05).Logistic study revealed Dlasma ox-LDL and serum hs-CRP were positively correlated with ACS.Conclusion Plasma ox-LDL and serum hs-CRP can reflect the severity of atherosclerotic CAD,and have great value in assessing the severity of the lesions and plaque stability in ACS.%目的 探讨血浆氧化低密度脂蛋白(ox-LDL)及血清高敏C-反应蛋白(hs-CRP)水平与急性冠脉综合征(ACS)的关系.方法 根据临床诊断标准,将69名冠心病患者分为急性心肌梗死组、不稳定型心绞痛组和稳定型心绞痛组3组,另选取20例冠脉造影正常者为对照组,采用ELISA法测定患者血浆ox-LDL及血清hs-CRP.结果 急性心肌梗死组和不稳定型心绞痛组血浆ox-LDL及血清hs-CRP水平明显高于稳定性心绞痛和对照组(P<0.01);血浆ox-LDL和血清hs-CRP在对照组无相关性(r=0.084,P>0.05),在冠心病组呈高度正相关(r=0.801,P<0.01);在冠心病组,血浆ox-LDL与Gensini积分无相关性(r=-0.051,P>0.05);Logistic回归分析发现血浆ox-LDL及血清hs-CRP水平与ACS呈正相关.结论 血浆ox-LDL及血清hs-CRP水平不仅反映冠心病患者病变的严重程度,

  17. Studies on high chemical reactivity of nano-NaH

    Institute of Scientific and Technical Information of China (English)

    FAN Yinheng; ZOU Yunling; JIN Dan; WU Qiang; LIU Tong; XU Jie

    2007-01-01

    A comparison between the initial reaction rates of nanometric and commercial Nail has been studied in four test reactions: 1) hydrogenolysis of chlorobenzene; 2) selec-tive reduction of cinnamaldehyde to cinnamyl alcohol; 3)metallation of dimethyl sulfoxide; and 4) catalytic hydroge-nation ofolefins. The experimental results indicate that when Nail is used as a chemical reagent in the first three reactions,the initial reaction rates of nano-NaH is 230, 120 and 110 times higher than those of the commercial ones respectively,and it is in agreement with the difference in specific surface areas between these two forms of Nail. When Nail is used as a catalyst component together with Cp2TiCl2 in the fourth reaction, catalyst with nano-NaH gives extremely high activity in the hydrogenation of olefins, while the one with commercial Nail gives no activity at all even ifa large amount of the commercial Nail is used to make the total surface area equivalent to that of nano-NaH. Thus, it is evident that although large specific surface area is important for nano-Nail to be used as a catalyst component, high surface energy with surface defects seems to be more important. The largespecific surface and the activated surface of nano-NaH withhigh surface energy should be the main factors for thei rextremely high chemical reactivity, while whether the former or the latter one plays a leading role depends on the type of reactions involved.

  18. In situ analysis of size distribution of nano-particles in reactive plasmas using two dimensional laser light scattering method

    Science.gov (United States)

    Kamataki, K.; Morita, Y.; Shiratani, M.; Koga, K.; Uchida, G.; Itagaki, N.

    2012-04-01

    We have developed a simple in-situ method for measuring the size distribution (the mean size (mean diameter) and size dispersion) of nano-particles generated in reactive plasmas using the 2 dimensional laser light scattering (2DLLS) method. The principle of the method is based on thermal coagulation of the nano-particles, which occurs after the discharge is turned off, and the size and density of the nano-particles can then be deduced. We first determined the 2D spatial distribution of the density and size of the nano-particles in smaller particle size (a few nm) range than ones deduced from the conventional 2DLLS method. From this 2D dataset, we have for the first time been able to determine the size distribution of nano-particles generated in a reactive plasma without ex-situ measurements.

  19. Inductive couple plasma reactive ion etching characteristics of TiO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Garay, Adrian Adalberto; Hwang, Su Min; Chung, Chee Won, E-mail: cwchung@inha.ac.kr

    2015-07-31

    Changes in the inductively coupled plasma reactive ion etching characteristics of TiO{sub 2} thin films in response to the addition of HBr, Cl{sub 2} and C{sub 2}F{sub 6} to Ar gas were investigated. As the HBr, Cl{sub 2} and C{sub 2}F{sub 6} concentration increased, the etch rate increased; however, the etch profile degree of anisotropy followed a different trend. As HBr concentration increased, the greatest anisotropic etch profile was obtained at 100% HBr, while the greatest anisotropic etch profile was obtained at concentrations of 25% when etching was conducted under C{sub 2}F{sub 6} and Cl{sub 2}. Field emission scanning electron microscopy revealed that 25% C{sub 2}F{sub 6} generated the greatest vertical etch profile; hence, etch parameters were varied at this concentration. The effects of rf power, dc-bias voltage and gas pressure on the etch rate and etch profile were also investigated. The etch rate and degree of anisotropy in the etch profile increased with increasing rf power and dc-bias voltage and decreasing gas pressure. X-ray photoelectron spectroscopy analysis of the films etched under a C{sub 2}F{sub 6}/Ar gas mixture revealed the existence of etch byproducts containing F (i.e. TiF{sub x}) over the film. C{sub x}F{sub y} compounds were not detected on the film surface, probably due to contamination with atmospheric carbon. - Highlights: • Reactive ion etching of TiO{sub 2} films under HBr, C{sub 2}F{sub 6}, and Cl{sub 2} gases was studied. • Etch rate and etch profile of TiO{sub 2} films were investigated under each gas chemistry. • The highest degree of anisotropy was achieved at 25% C{sub 2}F{sub 6}/Ar. • Strong etch conditions at 25% C{sub 2}F{sub 6}/Ar increased etch rate and degree of anisotropy. • X-ray photoelectron spectroscopy revealed the existence of F-containing etch residues.

  20. High latitude electromagnetic plasma wave emissions

    Science.gov (United States)

    Gurnett, D. A.

    1983-01-01

    The principal types of electromagnetic plasma wave emission produced in the high latitude auroral regions are reviewed. Three types of radiation are described: auroral kilometric radiation, auroral hiss, and Z mode radiation. Auroral kilometric radiation is a very intense radio emission generated in the free space R-X mode by electrons associated with the formation of discrete auroral arcs in the local evening. Theories suggest that this radiation is an electron cyclotron resonance instability driven by an enhanced loss cone in the auroral acceleration region at altitudes of about 1 to 2 R sub E. Auroral hiss is a somewhat weaker whistler mode emission generated by low energy (100 eV to 10 keV) auroral electrons. The auroral hiss usually has a V shaped frequency time spectrum caused by a freqency dependent beaming of the whistler mode into a conical beam directed upward or downward along the magnetic field.

  1. Microstructure and oxidation resistance of reactive plasma clad Cr7C3 /γ-Fe ceramic composite coating

    Institute of Scientific and Technical Information of China (English)

    Liu Junbo

    2007-01-01

    A new type oxidation resistance in situ Cr7C3/γ-Fe ceramic composite coating was fabricated on hardened and tempered grade C steel by reactive plasma clad with Fe-Cr-C alloy powders. The oxidation resistance of the ceramic composite coating was investigated under the test condition of 900℃ and 50 hours. The results indicate that the coating has a rapidly solidified microstructure consisting of blocky primary Cr7C3 and the inter-blocky Cr7C3/γ-Fe eutectics and is metallurgically bonded to the hardened and tempered grade C steel substrate. The high temperature oxidation resistance of the coating is up to 1.9 times higher than that of grade C steel. The oxidation kinetics curve of the coating is conforming to the parabolic-rate law equation. The excellent oxidation resistance of the coating is mainly attributed to the continuous oxide films which consist of Cr2O3 and Fe2O3. The continuous oxide films can prevent the inner part of the coating from being further oxidized.

  2. High harmonic fast waves in high beta plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Masayuki

    1995-04-01

    High harmonic fast magnetosonic wave in high beta/high dielectric plasmas is investigated. including the finite-Larmor-radius effects. In this regime, due to the combination of group velocity slow down and the high beta enhancement, the electron absorption via electron Landau and electron magnetic pumping becomes significant enough that one can expect a strong ({approximately} 100%) single pass absorption. By controlling the wave spectrum, the prospect of some localized electron heating and current drive appears to be feasible in high beta low-aspect-ratio tokamak regimes. Inclusion of finite-Larmor-radius terms shows an accessibility limit in the high ion beta regime ({beta}{sub i} = 50% for a deuterium plasma) due to mode-conversion into an ion Bernstein-wave-like mode while no beta limit is expected for electrons. With increasing ion beta, the ion damping can increase significantly particularly near the beta limits. The presence of energetic ion component expected during intense NBI and {alpha}-heating does not appear to modify the accessibility condition nor cause excessive wave absorption.

  3. Layer-by-layer thinning of MoSe2 by soft and reactive plasma etching

    Science.gov (United States)

    Sha, Yunfei; Xiao, Shaoqing; Zhang, Xiumei; Qin, Fang; Gu, Xiaofeng

    2017-07-01

    Two-dimensional (2D) transition metal dichalcogenides (TMDs) like molybdenum diselenide (MoSe2) have recently gained considerable interest since their properties are complementary to those of graphene. Unlike gapless graphene, the band structure of MoSe2 can be changed from the indirect band gap to the direct band gap when MoSe2 changed from bulk material to monolayer. This transition from multilayer to monolayer requires atomic-layer-precision thining of thick MoSe2 layers without damaging the remaining layers. Here, we present atomic-layer-precision thinning of MoSe2 nanaosheets down to monolayer by using SF6 + N2 plasmas, which has been demonstrated to be soft, selective and high-throughput. Optical microscopy, atomic force microscopy, Raman and photoluminescence spectra suggest that equal numbers of MoSe2 layers can be removed uniformly regardless of their initial thickness, without affecting the underlying SiO2 substrate and the remaining MoSe2 layers. By adjusting the etching rates we can achieve complete MoSe2 removal and any disired number of MoSe2 layers including monolayer. This soft plasma etching method is highly reliable and compatible with the semiconductor manufacturing processes, thereby holding great promise for various 2D materials and TMD-based devices.

  4. Second Topical Conference on High-Temperature Plasma Diagnostics

    Science.gov (United States)

    1978-02-01

    1 and is employed to make routine measurements of the evolution of plasma density in the high density ( n > 5 x 1011* cm-3) Alcator A tokamak...plasmas. To exemplify the use of these techniques in fusion plasmas, studies of density fluc- tuations in the ATC and ALCATOR tokamaks will be...character- istics for the excessive incidence of plasma light. Video signals are recorded with a video tape recorder, which starts and stops recording

  5. Assessment of reactivity transient experiments with high burnup fuel

    Energy Technology Data Exchange (ETDEWEB)

    Ozer, O.; Yang, R.L.; Rashid, Y.R.; Montgomery, R.O.

    1996-03-01

    A few recent experiments aimed at determining the response of high-burnup LWR fuel during a reactivity initiated accident (RIA) have raised concerns that existing failure criteria may be inappropriate for such fuel. In particular, three experiments (SPERT CDC-859, NSRR HBO-1 and CABRI REP Na-1) appear to have resulted in fuel failures at only a fraction of the anticipated enthalpy levels. In evaluating the results of such RIA simulation experiments, however, it is necessary that the following two key considerations be taken into account: (1) Are the experiments representative of conditions that LWR fuel would experience during an in-reactor RIA event? (2) Is the fuel that is being utilized in the tests representative of the present (or anticipated) population of LWR fuel? Conducting experiments under conditions that can not occur in-reactor can trigger response modes that could not take place during in-reactor operation. Similarly, using unrepresentative fuel samples for the tests will produce failure information that is of limited relevance to commercial LWR fuel. This is particularly important for high-burnup fuel since the manner under which the test samples are base-irradiated prior to the test will impact the mechanical properties of the cladding and will therefore affect the RIA response. A good example of this effect can be seen in the results of the SPERT CDC-859 test and in the NSRR JM-4 and JM-5 tests. The conditions under which the fuel used for these tests was fabricated and/or base-irradiated prior to the RIA pulse resulted in the formation of multiple cladding defects in the form of hydride blisters. When this fuel was subjected to the RIA power pulse, it failed by developing multiple cracks that were closely correlated with the locations of the pre-existing hydride blisters. In the case of the JM tests, many of the cracks formed within the blisters themselves and did not propagate beyond the heavily hydrided regions.

  6. An atmospheric-pressure cold plasma leads to apoptosis in Saccharomyces cerevisiae by accumulating intracellular reactive oxygen species and calcium

    Science.gov (United States)

    Ma, R. N.; Feng, H. Q.; Liang, Y. D.; Zhang, Q.; Tian, Y.; Su, B.; Zhang, J.; Fang, J.

    2013-07-01

    A non-thermal plasma is known to induce apoptosis of various cells but the mechanism is not yet clear. A eukaryotic model organism Saccharomyces cerevisiaewas used to investigate the cellular and biochemical regulations of cell apoptosis and cell cycle after an atmospheric-pressure cold plasma treatment. More importantly, intracellular calcium (Ca2+) was first involved in monitoring the process of plasma-induced apoptosis in this study. We analysed the cell apoptosis and cell cycle by flow cytometry and observed the changes in intracellular reactive oxygen species (ROS) and Ca2+ concentration, cell mitochondrial membrane potential (Δψm) as well as nuclear DNA morphology via fluorescence staining assay. All experimental results indicated that plasma-generated ROS leads to the accumulation of intracellular ROS and Ca2+ that ultimately contribute to apoptosis associated with cell cycle arrest at G1 phase through depolarization of Δψm and fragmenting nuclear DNA. This work provides a novel insight into the physical and biological mechanism of apoptosis induced by a plasma which could benefit for promoting the development of plasmas applied to cancer therapy.

  7. Plasma C-reactive protein and homocysteine concentrations are related to frequent fruit and vegetable intake in Hispanic and non-Hispanic white elders.

    Science.gov (United States)

    Gao, Xiang; Bermudez, Odilia I; Tucker, Katherine L

    2004-04-01

    Elevated C-reactive protein (CRP) and plasma total homocysteine (Hcy) were recently identified as risk factors for cardiovascular disease. However, few studies have related fruit and vegetable consumption to these markers of inflammation and B vitamin deficiency, particularly in the Hispanic population. We examined the relation of fruit and vegetable intake with plasma CRP and Hcy concentrations in a cross-sectional study. Subjects were 445 Hispanic elders and 154 neighborhood-based non-Hispanic white elders living in Massachusetts. Diet was assessed with a FFQ designed for this population. There were significant inverse dose-response associations between fruit and vegetable intake and plasma CRP (P for trend = 0.010) and Hcy (P for trend = 0.033) concentrations, after adjustment for potential confounders. The prevalence of high plasma CRP (> 10 mg/L), and high Hcy (>10.4 micromol/L for women and >11.4 micromol/L for men), was significantly greater among subjects in the lowest quartile of fruit and vegetable consumption relative to those in the highest quartile, 17.9 vs. 9.1% and 58.7 vs. 44.4%, respectively. With each additional serving of fruit and vegetable intake, adjusted odd ratios for high plasma CRP and Hcy were 0.79 (95% CI: 0.65 to 0.97) and 0.83 (95% CI: 0.72 to 0.96), respectively. Greater frequency of fruit and vegetable intake was associated with significantly lower plasma CRP and Hcy concentrations. Because both of these metabolites are known risk factors for CVD, these findings contribute to the evidence that a higher intake of fruit and vegetables may reduce the risk of CVD.

  8. Longitudinal changes in C-reactive protein, proform of eosinophil major basic protein, and pregnancy-associated plasma protein-A during weight changes in obese children

    DEFF Research Database (Denmark)

    Lausten-Thomsen, Ulrik; Gamborg, Michael; Bøjsøe, Christine

    2015-01-01

    BACKGROUND: Childhood obesity is associated with several complications, including cardiovascular comorbidity. Several biomarkers, such as high-sensitive C-reactive protein (hs-CRP), proform of eosinophil major basic protein (Pro-MBP) and pregnancy associated plasma protein-A (PAPP-A), have equally...... been linked to increased cardiovascular susceptibility. This study investigates these biomarkers during weight loss and regain in obese children. MATERIALS AND METHODS: A longitudinal study during a 12-week weight loss program with a 28 months follow-up was conducted. Anthropometrics and plasma......), and 2.70 (girls) were included. Ninety children completed the weight loss program and 68 children entered the follow-up program. Pro-MBP and PAPP-A, but not hs-CRP, exhibited individual-specific levels (tracking) during weight loss and regain. The PAPP-A/Pro-MBP correlation was strong, whereas the hs...

  9. Argon plasma inductively coupled plasma reactive ion etching study for smooth sidewall thin film lithium niobate waveguide application

    Science.gov (United States)

    Ulliac, G.; Calero, V.; Ndao, A.; Baida, F. I.; Bernal, M.-P.

    2016-03-01

    Lithium Niobate (LN) exhibits unique physical properties such as remarkable electro-optical coefficients and it is thus an excellent material for a wide range of fields like optic communications, lasers, nonlinear optical applications, electric field optical sensors etc. In order to further enhance the optical device performance and to be competitive with silicon photonics, sub-micrometric thickness lithium niobate films are crucial. A big step has been achieved with the development of LN thin films by using smart cut technology and wafer bonding and these films are nowadays available in the market. However, it is a challenge to obtain the requirements of the high quality thin LN film waveguide. In this letter, we show smooth ridge waveguides fabricated on 700 nm thickness thin film lithium niobate (TFLN). The fabrication has been done by developing and optimizing three steps of the technological process, the mask fabrication, the plasma etching, and a final cleaning wet etching step in order to remove the lithium niobate redeposition on the side walls. We have obtained single mode propagation with light overall losses of only 5 dB/cm.

  10. Differential regulation of self-reactivity discriminates between IgG+ human circulating memory B cells and bone marrow plasma cells.

    Science.gov (United States)

    Scheid, Johannes F; Mouquet, Hugo; Kofer, Juliane; Yurasov, Sergey; Nussenzweig, Michel C; Wardemann, Hedda

    2011-11-01

    Long-term humoral immunity is maintained by the formation of high-affinity class-switched memory B cells and long-lived antibody-secreting plasma cells. In healthy humans, a substantial fraction of IgG-positive memory B cells express self-reactive and polyreactive IgG antibodies that frequently develop by somatic mutations. Whether self- and polyreactive IgG-secreting B cells are also tolerated in the long-lived plasma cell pool is not known. To address this question, we cloned and expressed the Ig genes from 177 IgG-producing bone marrow plasma cells of four healthy donors. All antibodies were highly mutated but the frequency of self- and polyreactive IgG antibodies was significantly lower than that found in circulating memory B cells. The data suggest that in contrast to the development of memory B cells, entry into the bone marrow plasma cell compartment requires previously unappreciated selective regulation by mechanisms that limit the production of self- and polyreactive serum IgG antibodies.

  11. Reactive Control of Boundary Layer Streaks Induced by Freestream Turbulence Using Plasma Actuators

    Science.gov (United States)

    Gouder, Kevin; Naguib, Ahmed; Lavoie, Philippe; Morrison, Jonathan

    2015-11-01

    Over the past few years we have carried out a systematic series of investigations aimed at evaluating the capability of a plasma-actuator-based feedforward-feedback control system to weaken streaks induced ``synthetically'' in a Blasius boundary layer via dynamic roughness elements. This work has been motivated by the delay of bypass boundary layer transition in which the streaks form stochastically beneath a freestream with turbulence of intensity of more than approximately 1%. In the present work, we carry forward the knowhow from our previous research in a first attempt to control such naturally occurring streaks. The experimental setup consists of a turbulence-generating grid upstream of a flat plate with a sharp leading edge. At the freestream velocity of the experiment, turbulent spot formation is observed to start at a streamwise location of x ~ 350 mm from the leading edge. The control system is implemented within a streamwise domain stretching from x = 150 mm to 300mm, where the streaks exhibit linear growth. At the upstream and downstream end of the domain a feedforward and a feedback wall-shear-stress sensors are utilized. The output from the sensors is fed to appropriately designed controllers which drive two plasma actuators providing positive and negative wall-normal forcing to oppose naturally occurring high- and low-speed streaks respectively. The results provide an assessment of the viability of the control approach to weaken the boundary layer streaks and to delay transition.

  12. Preparative soft and reactive landing of gas-phase ions on plasma-treated metal surfaces.

    Science.gov (United States)

    Volný, Michael; Elam, W Timothy; Ratner, Buddy D; Turecek, Frantisek

    2005-08-01

    Soft landing of singly charged gas-phase ions on dry metal surfaces that were pretreated in situ by oxygen plasma results in 0.1-2% total yields of recovered intact compounds. Lysine, peptides, crystal violet dye, and a biotin conjugate are found to survive soft landing of hyperthermal ions of up to 50-eV kinetic energy. Soft landing at 40-50-eV ion kinetic energies of a fluorescence-labeled biotin conjugate results in an immobilized fraction that cannot be washed from the surface and is found to contain an intact biotin moiety. The present results represent an approximately 10(4) fold improvement in soft-landing efficiency and indicate that plasma-treated metal surfaces can be useful for preparative separation of organic and biological molecules by mass spectrometry. The substantial improvement in soft-landing yields results from a high transmission of electrosprayed ions into the vacuum system, efficient and nondestructive discharge of ions on the metal oxide surface, and facile analyte recovery in the absence of a matrix.

  13. Atomic processes in high-density plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1982-12-21

    This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)

  14. Influence of substrate pre-treatments by Xe{sup +} ion bombardment and plasma nitriding on the behavior of TiN coatings deposited by plasma reactive sputtering on 100Cr6 steel

    Energy Technology Data Exchange (ETDEWEB)

    Vales, S., E-mail: sandra.vales@usp.br [Universidade de São Paulo (USP), Escola de Engenharia de São Carlos, Av. Trabalhador São Carlense 400, São Carlos, SP CEP 13566-590 (Brazil); Brito, P., E-mail: ppbrito@gmail.com [Pontifícia Universidade Católica de Minas Gerais (PUC-MG), Av. Dom José Gaspar 500, 30535-901 Belo Horizonte, MG (Brazil); Pineda, F.A.G., E-mail: pipe8219@gmail.com [Universidade de São Paulo (USP), Escola de Engenharia de São Carlos, Av. Trabalhador São Carlense 400, São Carlos, SP CEP 13566-590 (Brazil); Ochoa, E.A., E-mail: abigail_ochoa@hotmail.com [Universidade Estadual de Campinas (UNICAMP), Campus Universitário Zeferino Vaz, Barão Geraldo, Campinas, SP CEP 13083-970 (Brazil); Droppa, R., E-mail: roosevelt.droppa@ufabc.edu.br [Universidade Federal do ABC (UFABC), Av. dos Estados, 5001, Santo André, SP CEP 09210-580 (Brazil); Garcia, J., E-mail: jose.garcia@sandvik.com [Sandvik Coromant R& D, Lerkrogsvägen 19, SE-12680, Stockholm (Sweden); Morales, M., E-mail: monieriz@gmail.com [Universidade Estadual de Campinas (UNICAMP), Campus Universitário Zeferino Vaz, Barão Geraldo, Campinas, SP CEP 13083-970 (Brazil); Alvarez, F., E-mail: alvarez@ifi.unicamp.br [Universidade Estadual de Campinas (UNICAMP), Campus Universitário Zeferino Vaz, Barão Geraldo, Campinas, SP CEP 13083-970 (Brazil); and others

    2016-07-01

    In this paper the influence of pre-treating a 100Cr6 steel surface by Xe{sup +} ion bombardment and plasma nitriding at low temperature (380 °C) on the roughness, wear resistance and residual stresses of thin TiN coatings deposited by reactive IBAD was investigated. The Xe{sup +} ion bombardment was carried out using a 1.0 keV kinetic energy by a broad ion beam assistance deposition (IBAD, Kaufman cell). The results showed that in the studied experimental conditions the ion bombardment intensifies nitrogen diffusion by creating lattice imperfections, stress, and increasing roughness. In case of the combined pre-treatment with Xe{sup +} ion bombardment and subsequent plasma nitriding, the samples evolved relatively high average roughness and the wear volume increased in comparison to the substrates exposed to only nitriding or ion bombardment. - Highlights: • Effect of Xe ion bombardment and plasma nitriding on TiN coatings was investigated. • Xe ion bombardment with 1.0 KeV increases nitrogen retention in plasma nitriding. • 1.0 KeV ion impact energy causes sputtering, thus increasing surface roughness. • TiN coating wear is minimum after plasma nitriding due to lowest roughness.

  15. Hampering Effect of Cholesterol on the Permeation of Reactive Oxygen Species through Phospholipids Bilayer: Possible Explanation for Plasma Cancer Selectivity

    Science.gov (United States)

    Van der Paal, Jonas; Verheyen, Claudia; Neyts, Erik C.; Bogaerts, Annemie

    2017-01-01

    In recent years, the ability of cold atmospheric pressure plasmas (CAPS) to selectively induce cell death in cancer cells has been widely established. This selectivity has been assigned to the reactive oxygen and nitrogen species (RONS) created in CAPs. To provide new insights in the search for an explanation for the observed selectivity, we calculate the transfer free energy of multiple ROS across membranes containing a varying amount of cholesterol. The cholesterol fraction is investigated as a selectivity parameter because membranes of cancer cells are known to contain lower fractions of cholesterol compared to healthy cells. We find that cholesterol has a significant effect on the permeation of reactive species across a membrane. Indeed, depending on the specific reactive species, an increasing cholesterol fraction can lead to (i) an increase of the transfer free energy barrier height and width, (ii) the formation of a local free energy minimum in the center of the membrane and (iii) the creation of extra free energy barriers due to the bulky sterol rings. In the context of plasma oncology, these observations suggest that the increased ingress of RONS in cancer cells can be explained by the decreased cholesterol fraction of their cell membrane. PMID:28059085

  16. Hampering Effect of Cholesterol on the Permeation of Reactive Oxygen Species through Phospholipids Bilayer: Possible Explanation for Plasma Cancer Selectivity

    Science.gov (United States)

    van der Paal, Jonas; Verheyen, Claudia; Neyts, Erik C.; Bogaerts, Annemie

    2017-01-01

    In recent years, the ability of cold atmospheric pressure plasmas (CAPS) to selectively induce cell death in cancer cells has been widely established. This selectivity has been assigned to the reactive oxygen and nitrogen species (RONS) created in CAPs. To provide new insights in the search for an explanation for the observed selectivity, we calculate the transfer free energy of multiple ROS across membranes containing a varying amount of cholesterol. The cholesterol fraction is investigated as a selectivity parameter because membranes of cancer cells are known to contain lower fractions of cholesterol compared to healthy cells. We find that cholesterol has a significant effect on the permeation of reactive species across a membrane. Indeed, depending on the specific reactive species, an increasing cholesterol fraction can lead to (i) an increase of the transfer free energy barrier height and width, (ii) the formation of a local free energy minimum in the center of the membrane and (iii) the creation of extra free energy barriers due to the bulky sterol rings. In the context of plasma oncology, these observations suggest that the increased ingress of RONS in cancer cells can be explained by the decreased cholesterol fraction of their cell membrane.

  17. Combined effect of protein and oxygen on reactive oxygen and nitrogen species in the plasma treatment of tissue

    Science.gov (United States)

    Gaur, Nishtha; Szili, Endre J.; Oh, Jun-Seok; Hong, Sung-Ha; Michelmore, Andrew; Graves, David B.; Hatta, Akimitsu; Short, Robert D.

    2015-09-01

    The influence of protein and molecular, ground state oxygen (O2) on the plasma generation, and transport of reactive oxygen and nitrogen species (RONS) in tissue are investigated. A tissue target, comprising a 1 mm thick gelatin film (a surrogate for real tissue), is placed on top of a 96-well plate; each well is filled with phosphate buffered saline (PBS, pH 7.4) containing one fluorescent or colorimetric reporter that is specific for one of three RONS (i.e., H2O2, NO2-, or OH•) or a broad spectrum reactive oxygen species reporter (2,7-dichlorodihydrofluorescein). A helium cold atmospheric plasma (CAP) jet contacts the top of the gelatin surface, and the concentrations of RONS generated in PBS are measured on a microplate reader. The data show that H2O2, NO2-, or OH• are generated in PBS underneath the target. Independently, measurements are made of the O2 concentration in the PBS with and without the gelatin target. Adding bovine serum albumin protein to the PBS or gelatin shows that protein either raises or inhibits RONS depending upon the O2 concentration. Our results are discussed in the context of plasma-soft tissue interactions that are important in the development of CAP technology for medicine, biology, and food manufacturing.

  18. Workshop on extremely high energy density plasmas and their diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Shozo (ed.)

    2001-09-01

    Compiled are the papers presented at the workshop on 'Extremely High Energy Density Plasmas and Their Diagnostics' held at National Institute for Fusion Science. The papers cover physics and applications of extremely high-energy density plasmas such as dense z-pinch, plasma focus, and intense pulsed charged beams. Separate abstracts were presented for 7 of the papers in this report. The remaining 25 were considered outside the subject scope of INIS. (author)

  19. Effects of the electrical parameters and gas flow rate on the generation of reactive species in liquids exposed to atmospheric pressure plasma jets

    Science.gov (United States)

    Baek, Eun Jeong; Joh, Hea Min; Kim, Sun Ja; Chung, T. H.

    2016-07-01

    In this work, an atmospheric pressure plasma jet was fabricated and studied for plasma-liquid interactions. The plasma jet consists of a quartz-covered pin electrode and outer quartz tube with a tapered nozzle. Using the current-voltage (I-V) and optical emission characteristics of the plasma jet, the plasma density and the speed of the plume were investigated. The optical emission spectra clearly indicated the excited NO, O, OH, N2, and N2+ in the plasma plumes. Then the plasma jets were applied to the deionized water. We investigated the effects of the operating parameters such as applied voltage, pulse frequency, and gas flow rate on the generation of reactive species in the gas and liquid phases. The densities of reactive species including OH radicals were obtained at the plasma-liquid surface and inside the plasma-treated liquids using ultraviolet absorption spectroscopy and chemical probe method. The nitrite concentration was detected by Griess assay. The data are very suggestive that there is a strong correlation among the production of reactive oxygen and nitrogen species (RONS) in the plasmas and liquids.

  20. Computational Simulation of High Energy Density Plasmas

    Science.gov (United States)

    2009-10-30

    the imploding liner. The PFS depends on a lithium barrier foil slowing the advance of deuterium up the coaxial gun to the corner. There the plasma ...the coaxial gun section, and Figure 4 shows the physical state of the plasma just prior to pinch. Figure 5 shows neutron yield reaching 1014 in this...details the channel geometry between the center cylinder and coaxial gas gun . The deuterium injection starts when the pressure of the deuterium gas in

  1. Erosion behaviour of composite Al-Cr cathodes in cathodic arc plasmas in inert and reactive atmospheres

    CERN Document Server

    Franz, Robert; Hawranek, Gerhard; Polcik, Peter

    2015-01-01

    Al$_{x}$Cr$_{1-x}$ composite cathodes with Al contents of x = 0.75, 0.5 and 0.25 were exposed to cathodic arc plasmas in Ar, N$_2$ and O$_2$ atmospheres and their erosion behaviour was studied. Cross-sectional analysis of the elemental distribution of the near-surface zone in the cathodes by scanning electron microscopy revealed the formation of a modified layer for all cathodes and atmospheres. Due to intermixing of Al and Cr in the heat-affected zone, intermetallic Al-Cr phases formed as evidenced by X-ray diffraction analysis. Cathode poisoning effects in the reactive N$_2$ and O$_2$ atmospheres were non-uniform as a result of the applied magnetic field configuration. With the exception of oxide islands on Al-rich cathodes, reactive layers were absent in the circular erosion zone, while nitrides and oxides formed in the less eroded centre region of the cathodes.

  2. High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HRMAS NMR) for Studies of Reactive Fabrics

    Science.gov (United States)

    2015-11-01

    Magnetic Resonance (HRMAS NMR) for Studies of Reactive Fabrics 5a. CONTRACT NUMBER W911SR-11-C-0047 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...ECBC-TR-1326 HIGH RESOLUTION MAGIC ANGLE SPINNING NUCLEAR MAGNETIC RESONANCE (HRMAS NMR) FOR STUDIES OF REACTIVE FABRICS David J. McGarvey...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT An analytical chemistry method is described for measuring the reactivity and permeation of

  3. Investigation of reactive plasma species created in SO2 by an inductively coupled RF discharge in E- and H-mode

    Science.gov (United States)

    Zaplotnik, Rok; Vesel, Alenka; Mozetic, Miran

    2016-10-01

    Optical emission spectroscopy (OES) and mass spectrometry were used to investigate the gas phase and surface reactions in inductively coupled SO2 plasma at various radiofrequency discharge powers up to 1000 W and gas pressures from 30 to 100 Pa. At such conditions, the plasma was created either in E- or in H-mode. In the E-mode, extensive radiation in the UV range was observed due to transitions of SO2 and SO molecules to the ground electronic states, whereas the other spectral features were marginal. At elevated powers, an abrupt transition to the H-mode occurred, where the total radiation increased for several orders of magnitude. Strong hysteresis was observed in the behaviour of all OES spectral features at the transitions between the E- and H-modes. In the H-mode, the atomic lines prevailed because of the relaxation of highly excited O and S atoms to the lower excited states, indicating high density of atoms. UV continuum was very weak and governed only by transitions of the SO radicals to the ground state. Thus, it was concluded that in the E-mode, predominantly SO and O radicals are formed during the partial dissociation of SO2 molecules, whereas in the H-mode, high dissociation to S and O atoms occurred, leading to the negligible concentration of SO2. However, in the flowing afterglow, the final gas composition was predominantly always SO2. The concentration of O2 was only approximately 3%, whereas the concentration of SO3 was marginal. This was explained by the recombination of the reactive plasma species formed in the plasma back to SO2 molecules on the surfaces of the remote plasma reactor.

  4. No relationship between lung function and high-sensitive C-reactive protein in adolescence.

    Science.gov (United States)

    Nybo, Mads; Hansen, Henrik Steen; Siersted, Hans Christian; Rasmussen, Finn

    2010-10-01

      Several studies on adults have indicated that lower spirometric lung function may be associated with increased systemic inflammation, but no studies have investigated if this association is already present in adolescence.   We explored the temporal relationship between changes in lung function and concentrations of plasma C-reactive protein (CRP) in a population-based cohort study at ages 14 and 20 years using a high-sensitivity CRP assay.   CRP measurements were performed in a total of 420 subjects at mean age of 13.9 years. Of these, 262 subjects (62%) participated in the follow-up investigation at mean age of 20.1 years.   Levels of log-CRP at age 14 were not significantly associated with forced expiratory volume (FEV(1) ) or FEV(1) / forced vital capacity (FVC) ratio at age 20, nor with the change in FEV(1) , FVC or FEV(1) /FVC ratio between 14 and 20 years after controlling for body mass index (BMI), airway hyperresponsiveness (AHR), eosinophil cationic protein (ECP), asthma, smoking, sex, and height at 14 years, and change in height between 14 and 20 years. Sex, BMI, AHR, ECP and change in height between 14 and 20 years were identified as independent factors associated with the change in FEV(1) , FVC and FEV(1) /FVC ratio in adolescence.   We did not find an association between CRP levels at age 14 and change in lung function by age 20; whereas, sex, change in height, BMI, AHR and ECP were associated with lung function change in adolescence. Our findings indicate that systemic inflammation is of less importance for change in lung function in adolescence. Please cite this paper as: Nybo M, Hansen HS, Siersted HC and Rasmussen F. No relationship between lung function and high-sensitive C-reactive protein in adolescence. © 2009 Blackwell Publishing Ltd.

  5. High throughput assay for evaluation of reactive carbonyl scavenging capacity

    Directory of Open Access Journals (Sweden)

    N. Vidal

    2014-01-01

    Full Text Available Many carbonyl species from either lipid peroxidation or glycoxidation are extremely reactive and can disrupt the function of proteins and enzymes. 4-hydroxynonenal and methylglyoxal are the most abundant and toxic lipid-derived reactive carbonyl species. The presence of these toxics leads to carbonyl stress and cause a significant amount of macromolecular damages in several diseases. Much evidence indicates trapping of reactive carbonyl intermediates may be a useful strategy for inhibiting or decreasing carbonyl stress-associated pathologies. There is no rapid and convenient analytical method available for the assessment of direct carbonyl scavenging capacity, and a very limited number of carbonyl scavengers have been identified to date, their therapeutic potential being highlighted only recently. In this context, we have developed a new and rapid sensitive fluorimetric method for the assessment of reactive carbonyl scavengers without involvement glycoxidation systems. Efficacy of various thiol- and non-thiol-carbonyl scavenger pharmacophores was tested both using this screening assay adapted to 96-well microplates and in cultured cells. The scavenging effects on the formation of Advanced Glycation End-product of Bovine Serum Albumin formed with methylglyoxal, 4-hydroxynonenal and glucose-glycated as molecular models were also examined. Low molecular mass thiols with an α-amino-β-mercaptoethane structure showed the highest degree of inhibitory activity toward both α,β-unsaturated aldehydes and dicarbonyls. Cysteine and cysteamine have the best scavenging ability toward methylglyoxal. WR-1065 which is currently approved for clinical use as a protective agent against radiation and renal toxicity was identified as the best inhibitor of 4-hydroxynonenal.

  6. Preoperative plasma plasminogen activator inhibitor type-1 and serum C-reactive protein levels in patients with colorectal cancer. The RANX05 Colorectal Cancer Study Group

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Christensen, Ib Jarle; Sørensen, Steen

    2000-01-01

    BACKGROUND: Preoperative plasma plasminogen activator inhibitor-1 (PAI-1) is a prognostic variable in patients with colorectal cancer. It has been suggested, however, that plasma PAI-1 is a nonspecific prognostic parameter similar to the acute-phase reactant C-reactive protein (CRP). In the present...... statistical analysis including Dukes classification, gender, age, tumor location, perioperative blood transfusion, PAI-1 and CRP, plasma PAI-1 was a dependent prognostic variable, while serum CRP (P

  7. Relationship between plasma lipoprotein-associated phospholipase A2,high sensitivity C reactive protein and left atrial diameter%脂蛋白相关性磷脂酶A2及高敏C反应蛋白与左心房内径的关系

    Institute of Scientific and Technical Information of China (English)

    崔占前; 徐延敏

    2015-01-01

    Objective:To observe the relationship between plasma levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) , high sensitivity C reactive protein (hs-CRP) and left atrial diameter (LAD) in patients with different types of atrial fibrillation(AF) and to explore the mechanism of inflammation-induced AF. Methods:One hundred and twenty two AF patients were divided into three groups:paroxysmal AF group (A, n=38), persistent AF group (B, n=40) and permanent AF group (C, n=44).Furthermore, forty-one sinus rhythm patients was randomly selected as control group (D, n=41). Basic clinical data and testing indexes of all groups were recorded. Results:Lp-PLA2 level in persistent and permanent AF group were significantly higher that in than paroxysmal AF and control groups(P<0.05). Hs-CRP levels in persistent and permanent groups were higher than those in paroxysmal and control groups. Paroxysmal group was also higher than control group (P<0.05). LAD in permanent and persistent groups were greater than paroxysmal and control groups (P<0.05). Hs-CRP was positively correlated with LAD in paroxysmal group. Hs-CRP and Lp-PLA2 were positively correlated with LAD both in persistent and permanent groups. Conclusion:Inflammation is an important factor for genesis, developing and sustaining AF. One mechanism may be related to inflammation induced atrial remolding.%目的:观察不同类型心房颤动(房颤)患者左心房内径(LAD)与脂蛋白相关性磷脂酶A2(Lp-PLA2)及高敏C-反应蛋白(hs-CRP)水平之间的关系,探讨炎症诱发房颤的机制。方法:将122例房颤患者分为阵发性房颤组38例,持续性房颤组40例,永久性房颤组44例,随机选取41例窦性心律患者为对照组,记录患者临床资料及检测指标。结果:Lp-PLA2水平在持续性房颤组及永久性房颤组明显高于阵发性房颤组及对照组(P<0.05)。hs-CRP水平在持续性房颤组及永久性房颤组高于阵发性房颤组

  8. Development of high energy pulsed plasma simulator for plasma-lithium trench experiment

    Science.gov (United States)

    Jung, Soonwook

    To simulate detrimental events in a tokamak and provide a test-stand for a liquid lithium infused trench (LiMIT) device, a pulsed plasma source utilizing a theta pinch in conjunction with a coaxial plasma accelerator has been developed. An overall objective of the project is to develop a compact device that can produce 100 MW/m2 to 1 GW/m2 of plasma heat flux (a typical heat flux level in a major fusion device) in ~ 100 mus (≤ 0.1 MJ/m2) for a liquid lithium plasma facing component research. The existing theta pinch device, DEVeX, was built and operated for study on lithium vapor shielding effect. However, a typical plasma energy of 3 - 4 kJ/m2 is too low to study an interaction of plasma and plasma facing components in fusion devices. No or little preionized plasma, ringing of magnetic field, collisions of high energy particles with background gas have been reported as the main issues. Therefore, DEVeX is reconfigured to mitigate these issues. The new device is mainly composed of a plasma gun for a preionization source, a theta pinch for heating, and guiding magnets for a better plasma transportation. Each component will be driven by capacitor banks and controlled by high voltage / current switches. Several diagnostics including triple Langmuir probe, calorimeter, optical emission measurement, Rogowski coil, flux loop, and fast ionization gauge are used to characterize the new device. A coaxial plasma gun is manufactured and installed in the previous theta pinch chamber. The plasma gun is equipped with 500 uF capacitor and a gas puff valve. The increase of the plasma velocity with the plasma gun capacitor voltage is consistent with the theoretical predictions and the velocity is located between the snowplow model and the weak - coupling limit. Plasma energies measured with the calorimeter ranges from 0.02 - 0.065 MJ/m2 and increases with the voltage at the capacitor bank. A cross-check between the plasma energy measured with the calorimeter and the triple probe

  9. Increased diuresis, renal vascular reactivity, and blood pressure levels in young rats fed high sodium, moderately high fructose, or their association: a comparative evaluation.

    Science.gov (United States)

    Da Silva, Rita de Cássia Vilhena A F; de Souza, Priscila; da Silva-Santos, José Eduardo

    2016-12-01

    Excessive intakes of sodium or fructose have been described as risk factors for hypertension. We hypothesized that even a moderately high fructose diet (6% fructose), either alone or in combination with high sodium (4% NaCl), may impair diuresis and renal and systemic vascular reactivity, contributing to the onset of high blood pressure in rats. Male Wistar rats were fed chow containing 4% NaCl (HS), 6% fructose (MHF), or both 4% NaCl and 6% fructose (HSMHF) for 6 weeks and had their diuresis, plasma creatinine, vascular reactivity of perfused kidneys and systemic arterial pressure evaluated. We found no differences in augmented diuresis among animals given HS, MHF, or HSMHF diets. After 6 weeks both the HS and HSMHF groups had increased weight in their left kidneys, but only the HSMHF group showed augmented plasma creatinine. The effects of phenylephrine on renal vascular perfusion pressure were similarly enhanced in kidneys from the HS, MHF, and HSMHF groups, but not on the systemic arterial pressure. Although when evaluated in anesthetized rats, only the HSMHF group presented augmented blood pressure, evaluation in conscious animals revealed that both the MHF and HSMHF diets, but not the HS alone, were able to induce tachycardia and hypertension. In conclusion, a MHF diet containing 6% fructose was enough to render the renal vascular bed hyperreactive to phenylephrine and to induce both hypertension and tachycardia. The combination of 6% fructose with 4% NaCl led to plasma accumulation of creatinine and accelerated the development of tachycardia.

  10. High Temperature Plasmas Theory and Mathematical Tools for Laser and Fusion Plasmas

    CERN Document Server

    Spatschek, Karl-Heinz

    2012-01-01

    Filling the gap for a treatment of the subject as an advanced course in theoretical physics with a huge potential for future applications, this monograph discusses aspects of these applications and provides theoretical methods and tools for their investigation. Throughout this coherent and up-to-date work the main emphasis is on classical plasmas at high-temperatures, drawing on the experienced author's specialist background. As such, it covers the key areas of magnetic fusion plasma, laser-plasma-interaction and astrophysical plasmas, while also including nonlinear waves and phenomena.

  11. High speed cine film studies of plasma behaviour and plasma surface interactions in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Goodall, D.H.J. (Euratom/UKAEA Fusion Association, Abingdon (UK). Culham Lab.)

    High speed cine photography is a useful diagnostic aid for studying plasma behaviour and plasma surface interactions. Several workers have filmed discharges in tokamaks including ASDEX, DITE, DIVA, ISX, JFT2, TFR and PLT. These films are discussed and examples given of the observed phenomena which include plasma limiter interactions, diverted discharges, disruptions, magnetic islands and moving glowing objects often known as 'UFOs'. Examples of plasma structures in ASDEX and DITE not previously published are also given. The paper also reports experiments in DITE to determine the origin of UFOs.

  12. High heat flux plasma generator for new divertor plasma simulator in Nagoya University

    Energy Technology Data Exchange (ETDEWEB)

    Narita, S.; Ezumi, N.; Ohno, N.; Uesugi, Y.; Takamura, S. [Nagoya Univ. (Japan)

    1997-12-31

    A new divertor simulator called NAGDIS-II has been constructed in order to investigate edge plasma physics in fusion devices. Improved TP-D type plasma source, which consists of LaB{sub 6} cathode with a Mo hollow shield and external heating system, water-cooled intermediate electrode and anode was employed to make a high density plasma in the NAGDIS-II. The performance and reliability of the discharge system was confirmed by quantitatively measuring neutral pressure, heating efficiency and plasma parameters. (author)

  13. Influence of ionic liquid and ionic salt on protein against the reactive species generated using dielectric barrier discharge plasma.

    Science.gov (United States)

    Attri, Pankaj; Sarinont, Thapanut; Kim, Minsup; Amano, Takaaki; Koga, Kazunori; Cho, Art E; Choi, Eun Ha; Shiratani, Masaharu

    2015-12-10

    The presence of salts in biological solution can affect the activity of the reactive species (RS) generated by plasma, and so they can also have an influence on the plasma-induced sterilization. In this work, we assess the influence that diethylammonium dihydrogen phosphate (DEAP), an ionic liquid (IL), and sodium chloride (NaCl), an ionic salt (IS), have on the structural changes in hemoglobin (Hb) in the presence of RS generated using dielectric barrier discharge (DBD) plasma in the presence of various gases [O2, N2, Ar, He, NO (10%) + N2 and Air]. We carry out fluorescence spectroscopy to verify the generation of (•)OH with or without the presence of DEAP IL and IS, and we use electron spin resonance (ESR) to check the generation of H(•) and (•)OH. In addition, we verified the structural changes in the Hb structure after treatment with DBD in presence and absence of IL and IS. We then assessed the structural stability of the Hb in the presence of IL and IS by using molecular dynamic (MD) simulations. Our results indicate that the IL has a strong effect on the conservation of the Hb structure relative to that of IS against RS generated by plasma.

  14. Plasma synthesis of titanium nitride, carbide and carbonitride nanoparticles by means of reactive anodic arc evaporation from solid titanium

    Energy Technology Data Exchange (ETDEWEB)

    Kiesler, D., E-mail: dennis.kiesler@uni-due.de; Bastuck, T.; Theissmann, R.; Kruis, F. E. [University of Duisburg-Essen, Institute of Technology for Nanostructures (NST) and Center for Nanointegration Duisburg-Essen (CENIDE) (Germany)

    2015-03-15

    Plasma methods using the direct evaporation of a transition metal are well suited for the cost-efficient production of ceramic nanoparticles. In this paper, we report on the development of a simple setup for the production of titanium-ceramics by reactive anodic arc evaporation and the characterization of the aerosol as well as the nanopowder. It is the first report on TiC{sub X}N{sub 1 − X} synthesis in a simple anodic arc plasma. By means of extensive variations of the gas composition, it is shown that the composition of the particles can be tuned from titanium nitride over a titanium carbonitride phase (TiC{sub X}N{sub 1 − X}) to titanium carbide as proven by XRD data. The composition of the plasma gas especially a very low concentration of hydrocarbons around 0.2 % of the total plasma gas is crucial to tune the composition and to avoid the formation of free carbon. Examination of the particles by HR-TEM shows that the material consists mostly of cubic single crystalline particles with mean sizes between 8 and 27 nm.

  15. High-current ion beam from a moving plasma

    Energy Technology Data Exchange (ETDEWEB)

    Dembinski, M.; John, P.K.; Ponomarenko, A.G.

    1979-05-01

    High-current ion beams in the 10--20-keV range are extracted from a moving plasma. Current densities up to 2.5 A/cm/sup 2/ are obtained at the plasma boundary, which is almost an order of magnitude larger than the Bohm current. Total currents of over 100 A are obtained from the plasma. Simple geometric focusing gives current densities approx.200 A/cm/sup 2/ at the focus.

  16. High density plasma production in a multicusp plasma generator with RF antenna

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Hanada, Masaya; Okumura, Yoshikazu; Tanaka, Masanobu [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1992-10-01

    A high density plasma was produced by radio-frequency in a multicusp plasma generator. The generator is a cylindrical chamber of 200 mm in inner diameter and 270 mm in length with 1-3 turn copper tube antenna. By injecting a 2 MHz, 20 kW RF into the multicusp plasma generator, hydrogen plasma of an ion saturation current density of 120 mA/cm{sup 2} and a hydrogen plasma of a density of 6.0 x 10{sup 11} cm{sup -3} was produced at a pressure of 0.6 Pa in the generator. The ion saturation current density was uniform over the central area of 100 mm in diameter. Coating the antenna with an insulator, we proved that the efficiency of the plasma production was improved. (author).

  17. High density plasma production in a multicusp plasma generator with RF antenna

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Hanada, Masaya; Okumura, Yoshikazu; Tanaka, Masanobu (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment)

    1992-10-01

    A high density plasma was produced by radio-frequency in a multicusp plasma generator. The generator is a cylindrical chamber of 200 mm in inner diameter and 270 mm in length with 1-3 turn copper tube antenna. By injecting a 2 MHz, 20 kW RF into the multicusp plasma generator, hydrogen plasma of an ion saturation current density of 120 mA/cm[sup 2] and a hydrogen plasma of a density of 6.0 x 10[sup 11] cm[sup -3] was produced at a pressure of 0.6 Pa in the generator. The ion saturation current density was uniform over the central area of 100 mm in diameter. Coating the antenna with an insulator, we proved that the efficiency of the plasma production was improved. (author).

  18. High Current, High Density Arc Plasma as a New Source for WiPAL

    Science.gov (United States)

    Waleffe, Roger; Endrizzi, Doug; Myers, Rachel; Wallace, John; Clark, Mike; Forest, Cary; WiPAL Team

    2016-10-01

    The Wisconsin Plasma Astrophysics Lab (WiPAL) has installed a new array of nineteen plasma sources (plasma guns) on its 3 m diameter, spherical vacuum vessel. Each gun is a cylindrical, molybdenum, washer-stabilized, arc plasma source. During discharge, the guns are maintained at 1.2 kA across 100 V for 10 ms by the gun power supply establishing a high density plasma. Each plasma source is fired independently allowing for adjustable plasma parameters, with densities varying between 1018 -1019 m-3 and electron temperatures of 5-15 eV. Measurements were characterized using a 16 tip Langmuir probe. The plasma source will be used as a background plasma for the magnetized coaxial plasma gun (MCPG), the Terrestrial Reconnection Experiment (TREX), and as the plasma source for a magnetic mirror experiment. Temperature, density, and confinement results will be presented. This work is supported by the DoE and the NSF.

  19. Influence of reactive species on the modification of biomolecules generated from the soft plasma.

    Science.gov (United States)

    Attri, Pankaj; Kumar, Naresh; Park, Ji Hoon; Yadav, Dharmendra Kumar; Choi, Sooho; Uhm, Han S; Kim, In Tae; Choi, Eun Ha; Lee, Weontae

    2015-02-04

    Plasma medicine is an upcoming research area that has attracted the scientists to explore more deeply the utility of plasma. So, apart from the treating biomaterials and tissues with plasma, we have studied the effect of soft plasma with different feeding gases such as Air, N2 and Ar on modification of biomolecules. Hence, in this work we have used the soft plasma on biomolecules such as proteins ((Hemoglobin (Hb) and Myoglobin (Mb)), calf thymus DNA and amino acids. The structural changes or structural modification of proteins and DNA have been studied using circular dichroism (CD), fluorescence spectroscopy, protein oxidation test, gel electrophoresis, UV-vis spectroscopy, dynamic light scattering (DLS) and 1D NMR, while Liquid Chromatograph/Capillary Electrophoresis-Mass Spectrometer (LC/CE-MS) based on qualitative and quantitative bio-analysis have been used to study the modification of amino acids. Further, the thermal analysis of the protein has been studied with differential scanning calorimetry (DSC) and CD. Additionally, we have performed docking studies of H2O2 with Hb and Mb, which reveals that H2O2 molecules preferably attack the amino acids near heme group. We have also shown that N2 gas plasma has strong deformation action on biomolecules and compared to other gases plasma.

  20. Influence of reactive species on the modification of biomolecules generated from the soft plasma

    Science.gov (United States)

    Attri, Pankaj; Kumar, Naresh; Park, Ji Hoon; Yadav, Dharmendra Kumar; Choi, Sooho; Uhm, Han S.; Kim, In Tae; Choi, Eun Ha; Lee, Weontae

    2015-02-01

    Plasma medicine is an upcoming research area that has attracted the scientists to explore more deeply the utility of plasma. So, apart from the treating biomaterials and tissues with plasma, we have studied the effect of soft plasma with different feeding gases such as Air, N2 and Ar on modification of biomolecules. Hence, in this work we have used the soft plasma on biomolecules such as proteins ((Hemoglobin (Hb) and Myoglobin (Mb)), calf thymus DNA and amino acids. The structural changes or structural modification of proteins and DNA have been studied using circular dichroism (CD), fluorescence spectroscopy, protein oxidation test, gel electrophoresis, UV-vis spectroscopy, dynamic light scattering (DLS) and 1D NMR, while Liquid Chromatograph/Capillary Electrophoresis-Mass Spectrometer (LC/CE-MS) based on qualitative and quantitative bio-analysis have been used to study the modification of amino acids. Further, the thermal analysis of the protein has been studied with differential scanning calorimetry (DSC) and CD. Additionally, we have performed docking studies of H2O2 with Hb and Mb, which reveals that H2O2 molecules preferably attack the amino acids near heme group. We have also shown that N2 gas plasma has strong deformation action on biomolecules and compared to other gases plasma.

  1. Characteristics of patients with primary and late latent syphilis patients who were initially non-reactive to the rapid plasma reagin test.

    Science.gov (United States)

    Jun, Li; He-Yi, Zheng

    2013-01-01

    We aimed at determining the characteristics of patients with primary and late latent syphilis who were non-reactive on initial screening by rapid plasma reagin (RPR) but reactive by treponemal tests. We collected the RPR test results of all primary and late latent syphilis patients in our hospital from December 2000 to March 2012. The characteristics of syphilis patients who were non-reactive by RPR testing were compared to those of reactive patients. Multiple logistic regression was used to identify factors associated with non-reactive RPR results. Among primary syphilis patients, 37 (16.5%) were non-reactive on initial RPR and were compared with the 187 reactive cases. Age >35 years was an independent factor associated with a non-reactive result in primary cases (odds ratio [OR], 95% confidence intervals [CI] = 3.55 [1.39-9.07]). Of the late latent patients, 61 (8.8%) were non-reactive by RPR and 636 were reactive. Age >34 years was also an independent factor associated with a non-reactive result in late latent cases (OR [95% CI] = 4.30 [2.28-8.12]). This study suggests that RPR testing alone is insufficient to diagnose primary and late latent infections, especially in middle-aged and elderly individuals. Syphilis detection was lower for patients with primary syphilis than for those with late latent syphilis based on the results of the RPR.

  2. High-frequency electric field amplification in a magnetized plasma

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, Aleksandr V [Russian Research Centre ' Kurchatov Institute' , Moscow (Russian Federation)

    2006-11-30

    In the investigation of cyclotron ion heating in systems designed for plasma isotope separation, the high-frequency (HF) electric field amplification effect was found to occur in equilibrium plasma. In the present article this effect is treated as a result of the interaction of the plasma placed in a constant external magnetic field with the HF modes of the vacuum chamber. Consistent elaboration of this approach allowed obtaining a clear interpretation of the HF electric field amplification effect and constructing a simple model of HF field excitation in a plasma column embedded in the external magnetic field. (methodological notes)

  3. High-pressure ignition plasma torch for aerospace testing facilities

    Science.gov (United States)

    Yusupov, D. I.; Kulikov, Yu M.; Gadzhiev, M. Kh; Tyuftyaev, A. S.; Son, E. E.

    2016-11-01

    The present paper discusses the issues of implementation of high-pressure ignition plasma torch in terms of discharge phenomena in compressed gases, dense nitrogen plasma properties and stable arcing power requirements. Contact ignition has been tested in a pressure range p = 1-25 bar and has proved to be a reliable solution for pilot arc burning.

  4. Plasma resonance in anisotropic layered high-Tc superconductors

    DEFF Research Database (Denmark)

    Sakai, Shigeki; Pedersen, Niels Falsig

    1999-01-01

    The plasma resonance is described theoretically by the inductive coupling model for a large stacked Josephson-junction system such as the intrinsic Josephson-junction array in anisotropic high- T-c superconductors. Eigenmodes of the plasma oscillation are analytically described and a numerical...

  5. Very high frequency plasma reactant for atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Il-Kwon; Yoo, Gilsang; Yoon, Chang Mo [School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Tae Hyung; Yeom, Geun Young [Department of Advanced Materials Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Kangsik; Lee, Zonghoon [School Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919 (Korea, Republic of); Jung, Hanearl; Lee, Chang Wan [School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Hyungjun, E-mail: hyungjun@yonsei.ac.kr [School of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Lee, Han-Bo-Ram, E-mail: hbrlee@inu.ac.kr [Department of Materials Science and Engineering, Incheon National University, 406-840 Incheon (Korea, Republic of)

    2016-11-30

    Highlights: • Fundamental research plasma process for thin film deposition is presented. • VHF plasma source for PE-ALD Al{sub 2}O{sub 3} was employed to reduce plasma damage. • The use of VHF plasma improved all of the film qualities and growth characteristics. - Abstract: Although plasma-enhanced atomic layer deposition (PE-ALD) results in several benefits in the formation of high-k dielectrics, including a low processing temperature and improved film properties compared to conventional thermal ALD, energetic radicals and ions in the plasma cause damage to layer stacks, leading to the deterioration of electrical properties. In this study, the growth characteristics and film properties of PE-ALD Al{sub 2}O{sub 3} were investigated using a very-high-frequency (VHF) plasma reactant. Because VHF plasma features a lower electron temperature and higher plasma density than conventional radio frequency (RF) plasma, it has a larger number of less energetic reaction species, such as radicals and ions. VHF PE-ALD Al{sub 2}O{sub 3} shows superior physical and electrical properties over RF PE-ALD Al{sub 2}O{sub 3}, including high growth per cycle, excellent conformality, low roughness, high dielectric constant, low leakage current, and low interface trap density. In addition, interlayer-free Al{sub 2}O{sub 3} on Si was achieved in VHF PE-ALD via a significant reduction in plasma damage. VHF PE-ALD will be an essential process to realize nanoscale devices that require precise control of interfaces and electrical properties.

  6. Effects of the pulse width on the reactive species production and DNA damage in cancer cells exposed to atmospheric pressure microsecond-pulsed helium plasma jets

    Science.gov (United States)

    Joh, Hea Min; Choi, Ji Ye; Kim, Sun Ja; Kang, Tae Hong; Chung, T. H.

    2017-08-01

    Plasma-liquid and plasma-cell interactions were investigated using an atmospheric pressure dc microsecond-pulsed helium plasma jet. We investigated the effects of the electrical parameters such as applied voltage and pulse width (determined by the pulse frequency and duty ratio) on the production of reactive species in the gas/liquid phases and on the DNA damage responses in the cancer cells. The densities of reactive species including OH radicals were estimated inside the plasma-treated liquids using a chemical probe method, and the nitrite concentration was detected by Griess assay. Importantly, the more concentration of OH resulted in the more DNA base oxidation and breaks in human lung cancer A549 cells. The data are very suggestive that there is strong correlation between the production of OH in the plasmas/liquids and the DNA damage.

  7. Plasma lecithin : cholesterol acyltransferase activity modifies the inverse relationship of C-reactive protein with HDL cholesterol in nondiabetic men

    NARCIS (Netherlands)

    Dullaart, R. P. F.; Perton, F.; Kappelle, P.J.W.H.; de Vries, R.; Sluiter, W. J.; van Tol, A.

    Lecithin:cholesterol acyltransferase (LCAT) is instrumental in high-density lipoprotein (HDL) maturation, but high LCAT levels do not predict low cardiovascular risk. LCAT may affect antioxidative or anti-inflammatory properties of HDL We determined the relationship of plasma high-sensitivity

  8. Generation of reactive oxygen and nitrogen species and its effects on DNA damage in lung cancer cells exposed to atmospheric pressure helium/oxygen plasma jets

    Science.gov (United States)

    Chung, Tae Hun; Joh, Hea Min; Kim, Sun Ja; Choi, Ji Ye; Kang, Tae-Hong

    2016-09-01

    We investigated the effects of the operating parameters on the generation of reactive oxygen and nitrogen species (RONS) in the gas and liquid phases exposed to atmospheric pressure a pulsed-dc helium plasma jets. The densities of reactive species including OH radicals were obtained at the plasma-liquid surface and inside the plasma-treated liquids using ultraviolet absorption spectroscopy and chemical probe method. And the nitrite concentration was detected by Griess assay. The data are very suggestive that there is a strong correlation among the production of RONS in the plasmas and liquids. Exposure of plasma to cancer cells increases the cellular levels of RONS, which has been linked to apoptosis and the damage of cellular proteins, and may also indirectly cause structural damage to DNA. To identify the correlation between the production of RONS in cells and plasmas, various assay analyses were performed on plasma treated human lung cancer cells (A549) cells. In addition, the effect of additive oxygen gas on the plasma-induced oxidative stress in cancer cells was investigated. It was observed that DNA damage was significantly increased with helium/oxygen plasma compared to with pure helium plasma.

  9. Effect of plasma jet diameter on the efficiency of reactive oxygen and nitrogen species generation in water

    Science.gov (United States)

    Oh, Jun-Seok; Kakuta, Maito; Furuta, Hiroshi; Akatsuka, Hiroshi; Hatta, Akimitsu

    2016-06-01

    The plasma jet generation of reactive oxygen and nitrogen species (RONS) in solution is important in biology, medicine, and disinfection. Studies using a wide variety of plasma jet devices have been carried out for this purpose, making it difficult to compare the performance between devices. In this study, we compared the efficiency of RONS generation in deionized (DI) water between 3.7-mm- and 800-µm-sized helium (He) plasma jets (hereafter mm-jet and µm-jet, respectively) at different treatment distances and times. The efficiency of RONS generation was determined by considering the total amount of RONS generated in DI water with respect to the input energy and gas consumption. We found that the mm-jet generated 20% more RONS in the DI water than the µm-jet at the optimized distance. However, when the input power and He gas consumption were taken into account, we discovered that the µm-jet was 5 times more efficient in generating RONS in the DI water. Under the parameters investigated in this study, the concentration of RONS continued to increase as a function of treatment time (up to 30 min). However treatment distance had a marked effect on the efficiency of RONS generation: treatment distances of 25 and 30 mm were optimal for the mm-jet and µm-jet, respectively. Our method of comparing the efficiency of RONS generation in solution between plasma jets could be used as a reference protocol for the development of efficient plasma jet sources for use in medicine, biology, and agriculture.

  10. Combustion Mode Design with High Efficiency and Low Emissions Controlled by Mixtures Stratification and Fuel Reactivity

    Directory of Open Access Journals (Sweden)

    Hu eWang

    2015-08-01

    Full Text Available This paper presents a review on the combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixture stratification that have been conducted in the authors’ group, including the charge reactivity controlled homogeneous charge compression ignition (HCCI combustion, stratification controlled premixed charge compression ignition (PCCI combustion, and dual-fuel combustion concepts controlled by both fuel reactivity and mixture stratification. The review starts with the charge reactivity controlled HCCI combustion, and the works on HCCI fuelled with both high cetane number fuels, such as DME and n-heptane, and high octane number fuels, such as methanol, natural gas, gasoline and mixtures of gasoline/alcohols, are reviewed and discussed. Since single fuel cannot meet the reactivity requirements under different loads to control the combustion process, the studies related to concentration stratification and dual-fuel charge reactivity controlled HCCI combustion are then presented, which have been shown to have the potential to achieve effective combustion control. The efforts of using both mixture and thermal stratifications to achieve the auto-ignition and combustion control are also discussed. Thereafter, both charge reactivity and mixture stratification are then applied to control the combustion process. The potential and capability of thermal-atmosphere controlled compound combustion mode and dual-fuel reactivity controlled compression ignition (RCCI/highly premixed charge combustion (HPCC mode to achieve clean and high efficiency combustion are then presented and discussed. Based on these results and discussions, combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixtures stratification in the whole operating range is proposed.

  11. High performance deuterium-tritium plasmas in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Sabbagh, S.A. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics; Batha, S.H. [Fusion Physics and Technology, Torrance, CA (United States); Bell, M.G. [Princeton Univ., NJ (United States). Plasma Physics Lab.] [and others

    1995-03-01

    Plasmas composed of nominally equal concentrations of deuterium and tritium (DT) have been created in TFTR with the goals of producing significant levels of fusion power and of examining the effects of DT fusion alpha particles. Conditioning of the limiter by the injection of lithium pellets has led to an approximate doubling of the energy confinement time, {tau}{sub E}, in supershot plasmas at high plasma current (I{sub p} {le} 2.5 MA) and high heating power (P{sub b} {le} 33 MW). Operation with DT typically results in an additional 20% increase in {tau}{sub E}. In the high poloidal beta, advanced tokamak regime in TFTR, confinement enhancement H {triple_bond} {tau}{sub E}/{tau}{sub E ITER-89P} > 4 has been obtained in a limiter H-mode configuration at moderate plasma current I{sub p} = 0.85 {minus} 1.5 MA. By peaking the plasma current profile, {beta}{sub N dia} {triple_bond} 10{sup 8} < {beta}{sub t{perpendicular}} > aB{sub 0}/I{sub p} = 3 has been obtained in these plasmas, exceeding the {beta}{sub N} limit for TFTR plasmas with lower internal inductance, l{sub i}. Confinement of alpha particles appears to be classical and losses due to collective effects have not been observed. While small fluctuations in fusion product loss were observed during ELMs, no large loss was detected in DT plasmas.

  12. HIGH PREVALENCE OF REACTIVE ARTHRITIS IN RUSSIA: OVERDIAGNOSIS OR REALITY?

    Directory of Open Access Journals (Sweden)

    R. M. Balabanova

    2015-01-01

    Full Text Available Reactive arthritis (ReA is one of the types of spondyloarthritis. According to the statistics reports by the Ministry of Health of Russia, the prevalence of ReA in 2013 was 42.8 per 100,000 adult population, 99, and 172.4 per 100,000 children aged 0–14 and 15–17 years, respectively. There is a wide scatter of ReA detection rates in both the federal districts and subjects of the Russian Federation, which may be associated with both the spread of sexually transmitted infections, asymptomatic trigger Chlamydia infection, and overdiagnosis of ReA.

  13. High density and high temperature plasmas in Large Helical Device

    Science.gov (United States)

    Komori, Akio

    2010-11-01

    Recently a new confinement regime called Super Dense Core (SDC) mode was discovered in Large Helical Device (LHD). An extremely high density core region with more than ~ 1 × 1021 m-3 is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB is very high and the particle confinement in the core region is ~ 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature up to 5.6 keV with the formation of the internal transport barrier (ITB). In the electron heating experiments with 77 GHz gyrotrons, the highest electron temperature more than 15 keV was achieved, where plasmas are in the neoclassical regime.

  14. High density and high temperature plasmas in Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Komori, Akio, E-mail: komori@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan)

    2010-11-01

    Recently a new confinement regime called Super Dense Core (SDC) mode was discovered in Large Helical Device (LHD). An extremely high density core region with more than {approx} 1 x 10{sup 21} m{sup -3} is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB is very high and the particle confinement in the core region is {approx} 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature up to 5.6 keV with the formation of the internal transport barrier (ITB). In the electron heating experiments with 77 GHz gyrotrons, the highest electron temperature more than 15 keV was achieved, where plasmas are in the neoclassical regime.

  15. High N-content a-C:N films elaborated by femtosecond PLD with plasma assistance

    Energy Technology Data Exchange (ETDEWEB)

    Maddi, C. [Université de Lyon, F-69003, Lyon, France, Université de Saint-Étienne, Laboratoire Hubert Curien (UMR 5516 CNRS) , 42000 Saint-Étienne (France); Donnet, C., E-mail: Christophe.Donnet@univ-st-etienne.fr [Université de Lyon, F-69003, Lyon, France, Université de Saint-Étienne, Laboratoire Hubert Curien (UMR 5516 CNRS) , 42000 Saint-Étienne (France); Loir, A.-S.; Tite, T. [Université de Lyon, F-69003, Lyon, France, Université de Saint-Étienne, Laboratoire Hubert Curien (UMR 5516 CNRS) , 42000 Saint-Étienne (France); Barnier, V. [Laboratoire Georges Friedel, Ecole Nationale Supérieure des Mines, 42023 Saint-Etienne (France); Rojas, T.C.; Sanchez-Lopez, J.C. [Instituto de Ciencia de Materiales de Sevilla (CSIC-US) , Avda. Américo Vespucio 49, 41092 Sevilla (Spain); Wolski, K. [Laboratoire Georges Friedel, Ecole Nationale Supérieure des Mines, 42023 Saint-Etienne (France); Garrelie, F. [Université de Lyon, F-69003, Lyon, France, Université de Saint-Étienne, Laboratoire Hubert Curien (UMR 5516 CNRS) , 42000 Saint-Étienne (France)

    2015-03-30

    Graphical abstract: - Highlights: • Nitrogen doped amorphous carbon films were deposited by DC reactive plasma femtosecond (fs) -PLD and conventional fs-PLD. • High nitrogen content in plasma assisted films. • More ordered sp2 rich graphitic clusters both in terms of structural and topological order. • Correlation length La of the clusters increases with nitrogen incorporation. • Formation of CN bonds at the expense of CC bonds with N content. • At the highest nitrogen concentration, terminal C≡N groups are incorporated in the film. • Correlation between film composition and plasma process. - Abstract: Amorphous carbon nitride (a-C:N) thin films are a interesting class of carbon-based electrode materials. Therefore, synthesis and characterization of these materials have found lot of interest in environmental analytical microsystems. Herein, we report the nitrogen-doped amorphous carbon thin film elaboration by femtosecond pulsed laser deposition (fs-PLD) both with and without a plasma assistance. The chemical composition and atomic bonding configuration of the films were investigated by multi-wavelength (MW) Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and electron energy-loss spectroscopy (EELS). The highest nitrogen content, 28 at.%, was obtained with plasma assistance. The I(D)/I(G) ratio and the G peak position increased as a function of nitrogen concentration, whereas the dispersion and full width at half maximum (FWHM) of G peak decreased. This indicates more ordered graphitic like structures in the films both in terms of topological and structural, depending on the nitrogen content. EELS investigations were correlated with MW Raman results. The interpretation of XPS spectra of carbon nitride films remains a challenge. Plasma assisted PLD in the femtosecond regime led to a significant high nitrogen concentration, which is highlighted on the basis of collisional processes in the carbon plasma plume interacting with the nitrogen

  16. Removal of carbon contaminations by RF plasma generated reactive species and subsequent effects on optical surface

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, P. K., E-mail: praveenyadav@rrcat.gov.in; Rai, S. K.; Modi, M. H.; Nayak, M.; Lodha, G. S. [Indus Synchrotron Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India); Kumar, M.; Chakera, J. A.; Naik, P. A. [Laser Plasma Laboratory, Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)

    2015-06-24

    Carbon contamination on optical elements is a serious issue in synchrotron beam lines for several decades. The basic mechanism of carbon deposition on optics and cleaning strategies are not fully understood. Carbon growth mechanism and optimized cleaning procedures are worldwide under development stage. Optimized RF plasma cleaning is considered an active remedy for the same. In present study carbon contaminated optical test surfaces (carbon capped tungsten thin film) are exposed for 30 minutes to four different gases, rf plasma at constant power and constant dynamic pressure. Structural characterization (thickness, roughness and density) of virgin samples and plasma exposed samples was done by soft x-ray (λ=80 Å) reflectivity measurements at Indus-1 reflectivity beam line. Different gas plasma removes carbon with different rate (0.4 to 0.65 nm /min). A thin layer 2 to 9 nm of different roughness and density is observed at the top surface of tungsten film. Ar gas plasma is found more suitable for cleaning of tungsten surface.

  17. Perspective: Is there a hysteresis during reactive High Power Impulse Magnetron Sputtering (R-HiPIMS)?

    Science.gov (United States)

    Strijckmans, K.; Moens, F.; Depla, D.

    2017-02-01

    This paper discusses a few mechanisms that can assist to answer the title question. The initial approach is to use an established model for DC magnetron sputter deposition, i.e., RSD2013. Based on this model, the impact on the hysteresis behaviour of some typical HiPIMS conditions is investigated. From this first study, it becomes clear that the probability to observe hysteresis is much lower as compared to DC magnetron sputtering. The high current pulses cannot explain the hysteresis reduction. Total pressure and material choice make the abrupt changes less pronounced, but the implantation of ionized metal atoms that return to the target seems to be the major cause. To further substantiate these results, the analytical reactive sputtering model is coupled with a published global plasma model. The effect of metal ion implantation is confirmed. Another suggested mechanism, i.e., gas rarefaction, can be ruled out to explain the hysteresis reduction. But perhaps the major conclusion is that at present, there are too little experimental data available to make fully sound conclusions.

  18. Investigations of nitrogen oxide plasmas: Fundamental chemistry and surface reactivity and monitoring student perceptions in a general chemistry recitation

    Science.gov (United States)

    Blechle, Joshua M.

    Part I of this dissertation focuses on investigations of nitrogen oxide plasma systems. With increasing concerns over the environmental presence of NxOy species, there is growing interest in utilizing plasma-assisted conversion techniques. Advances, however, have been limited because of the lack of knowledge regarding the fundamental chemistry of these plasma systems. Understanding the kinetics and thermodynamics of processes in these systems is vital to realizing their potential in a range of applications. Unraveling the complex chemical nature of these systems, however, presents numerous challenges. As such, this work serves as a foundational step in the diagnostics and assessment of these NxOy plasmas. The partitioning of energy within the plasma system is essential to unraveling these complications as it provides insight into both gas and surface reactivity. To obtain this information, techniques such as optical emission spectroscopy (OES), broadband absorption spectroscopy (BAS), and laser induced fluorescence (LIF) were utilized to determine species energetics (vibrational, rotational, translational temperatures). These temperature data provide mechanistic insight and establish the relationships between system parameters and energetic outcomes. Additionally, these data are also correlated to surface reactivity data collected with the Imaging of Radicals Interacting with Surfaces (IRIS) technique. IRIS data demonstrate the relationship between internal temperatures of radicals and their observed surface scatter coefficients (S), the latter of which is directly related to surface reactivity (R) [R = 1-S]. Furthermore, time-resolved (TR) spectroscopic techniques, specifically TR-OES, revealed kinetic trends in NO and N2 formation from a range of precursors (NO, N2O, N2/O2). By examining the rate constants associated with the generation and destruction of various plasma species we can investigate possible mechanistic implications. All told, such data provides

  19. The sub-micron hole array in sapphire produced by inductively-coupled plasma reactive ion etching.

    Science.gov (United States)

    Shiao, Ming-Hua; Chang, Chun-Ming; Huang, Su-Wei; Lee, Chao-Te; Wu, Tzung-Chen; Hsueh, Wen-Jeng; Ma, Kung-Jeng; Chiang, Donyau

    2012-02-01

    The sub-micron hole array in a sapphire substrate was fabricated by using nanosphere lithography (NSL) combined with inductively-coupled-plasma reactive ion etching (ICP-RIE) technique. Polystyrene nanospheres of about 600 nm diameter were self-assembled on c-plane sapphire substrates by the spin-coating method. The diameter of polystyrene nanosphere was modified by using oxygen plasma in ICP-RIE system. The size of nanosphere modified by oxygen plasma was varied from 550 to 450 nm with different etching times from 15 to 35 s. The chromium thin film of 100 nm thick was then deposited on the shrunk nanospheres on the substrate by electron-beam evaporation system. The honeycomb type chromium mask can be obtained on the sapphire substrate after the polystyrene nanospheres were removed. The substrate was further etched in two sets of chlorine/Argon and boron trichloride/Argon mixture gases at constant pressure of 50 mTorr in ICP-RIE processes. The 400 nm hole array in diameter can be successfully produced under suitable boron trichloride/Argon gas flow ratio.

  20. Plasma IL-6 concentration correlates with clinical disease activity and serum C-reactive protein concentration in chronic urticaria patients.

    Science.gov (United States)

    Kasperska-Zajac, A; Sztylc, J; Machura, E; Jop, G

    2011-10-01

    Our previous study was the first to demonstrate enhanced plasma IL-6 concentrations in chronic urticaria (CU). It is known that C-reactive protein (CRP) is a sensitive marker of an underlying systemic inflammation, triggered mainly as a response to IL-6. To evaluate plasma IL-6 concentration in CU patients relating to the clinical disease activity and serum CRP concentration. Serum CRP and plasma IL-6 concentrations were measured in 58 CU patients and 30 healthy subjects. Ten CU patients were evaluated twice, during the active period as well as upon the spontaneous clinical remission of the disease. CU activity was assessed with the use of the symptom scores recommended by EAACI/GALEN/EDF guidelines. IL-6 and CRP concentrations were significantly increased in CU patients as compared with the healthy subjects, whereas they decreased remarkably upon the spontaneous remission. IL-6 concentration was associated with weekly urticaria activity scores and also significant differences were found between patients showing different degrees of urticarial activity. Significant correlation was observed between IL-6 and CRP concentrations. This study reinforces evidence that, apart from a local cutaneous inflammation, CU is associated with a systemic inflammatory response. Such acute-phase response is manifested by increased circulating IL-6, which varies along with CRP changes and may be related to the urticarial activity. © 2011 Blackwell Publishing Ltd.

  1. Separation of VUV/UV photons and reactive particles in the effluent of a He/O2 atmospheric pressure plasma jet

    CERN Document Server

    Schneider, S; Narberhaus, F; Bandow, J E; Denis, B; Benedikt, J

    2011-01-01

    Cold atmospheric pressure plasmas can be used for treatment of living tissues or for inactivation of bacteria or biological macromolecules. The treatment is usually characterized by a combined effect of UV and VUV radiation, reactive species, and ions. This combination is usually beneficial for the effectiveness of the treatment but it makes the study of fundamental interaction mechanisms very difficult. Here we report on an effective separation of VUV/UV photons and heavy reactive species in the effluent of a micro scale atmospheric pressure plasma jet ($\\mu$-APPJ). The separation is realized by an additional flow of helium gas under well-defined flow conditions, which deflects heavy particles in the effluent without affecting the VUV and UV photons. Both components of the effluent, the photons and the reactive species, can be used separately or in combination for sample treatment. The results of treatment of a model plasma polymer film and vegetative Bacillus subtilis and Escherichia coli cells are shown an...

  2. Application of Plasma Waveguides to High Energy Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Milchberg, Howard [Univ. of Maryland, College Park, MD (United States)

    2016-07-01

    This grant supported basic experimental, theoretical and computer simulation research into developing a compact, high pulse repetition rate laser accelerator using the direct laser acceleration mechanism in plasma-based slow wave structures.

  3. Second topical conference on high-temperature plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Jahoda, F.C.; Freese, K.B. (comps.)

    1978-02-01

    This report contains the program and abstracts of papers presented at the Second American Physical Society Topical Conference on High Temperature Plasma Diagnostics, March 1-3, 1978, Santa Fe, New Mexico.

  4. Plasma instabilities in high electric fields

    DEFF Research Database (Denmark)

    Morawetz, K.; Jauho, Antti-Pekka

    1994-01-01

    We analyze nonequilibrium screening with nonequilibrium Green function techniques. By employing the generalized Kadanoff-Baym ansatz to relate the correlation function to the nonequilibrium distribution function, the latter of which is assumed to be a shifted Maxwellian, an analytically tractable...... expression is derived for the nonequilibrium dielectric function epsilon(K, omega). For certain values of momenta K and frequency omega, Imepsilon(K, omega) becomes negative, implying a plasma instability. This new instability exists only for strong electric fields, underlining its nonequilibrium origin....

  5. Plasma characteristics of a high power helicon discharge

    Science.gov (United States)

    Ziemba, T.; Euripides, P.; Slough, J.; Winglee, R.; Giersch, L.; Carscadden, J.; Schnackenberg, T.; Isley, S.

    2006-08-01

    A new high power helicon (HPH) plasma system has been designed to provide input powers of several tens of kilowatts to produce a large area (0.5 m2) of uniform high-density, of at least 5 × 1017 m-3, plasma downstream from the helicon coil. Axial and radial plasma characteristics show that the plasma is to a lesser extent created in and near the helicon coil and then is accelerated into the axial and equatorial regions. The bulk acceleration of the plasma is believed to be due to a coupling of the bulk of the electrons to the helicon field, which in turn transfers energy to the ions via ambipolar diffusion. The plasma beta is near unity a few centimetres away from the HPH system and Bdot measurements show ΔB perturbations in the order of the vacuum magnetic field magnitude. In the equatorial region, a magnetic separatrix is seen to develop roughly at the mid-point between the helicon and chamber wall. The magnetic perturbation develops on the time scale of the plasma flow speed and upon the plasma reaching the chamber wall decays to the vacuum magnetic field configuration within 200 µs.

  6. Plasma characteristics of a high power helicon discharge

    Energy Technology Data Exchange (ETDEWEB)

    Ziemba, T; Euripides, P; Slough, J; Winglee, R; Giersch, L; Carscadden, J; Schnackenberg, T; Isley, S [Box 351310, University of Washington, Seattle WA, 98195 (United States)

    2006-08-01

    A new high power helicon (HPH) plasma system has been designed to provide input powers of several tens of kilowatts to produce a large area (0.5 m{sup 2}) of uniform high-density, of at least 5 x 10{sup 17} m{sup -3}, plasma downstream from the helicon coil. Axial and radial plasma characteristics show that the plasma is to a lesser extent created in and near the helicon coil and then is accelerated into the axial and equatorial regions. The bulk acceleration of the plasma is believed to be due to a coupling of the bulk of the electrons to the helicon field, which in turn transfers energy to the ions via ambipolar diffusion. The plasma beta is near unity a few centimetres away from the HPH system and Bdot measurements show {delta}B perturbations in the order of the vacuum magnetic field magnitude. In the equatorial region, a magnetic separatrix is seen to develop roughly at the mid-point between the helicon and chamber wall. The magnetic perturbation develops on the time scale of the plasma flow speed and upon the plasma reaching the chamber wall decays to the vacuum magnetic field configuration within 200 {mu}s.

  7. Very high frequency plasma reactant for atomic layer deposition

    Science.gov (United States)

    Oh, Il-Kwon; Yoo, Gilsang; Yoon, Chang Mo; Kim, Tae Hyung; Yeom, Geun Young; Kim, Kangsik; Lee, Zonghoon; Jung, Hanearl; Lee, Chang Wan; Kim, Hyungjun; Lee, Han-Bo-Ram

    2016-11-01

    Although plasma-enhanced atomic layer deposition (PE-ALD) results in several benefits in the formation of high-k dielectrics, including a low processing temperature and improved film properties compared to conventional thermal ALD, energetic radicals and ions in the plasma cause damage to layer stacks, leading to the deterioration of electrical properties. In this study, the growth characteristics and film properties of PE-ALD Al2O3 were investigated using a very-high-frequency (VHF) plasma reactant. Because VHF plasma features a lower electron temperature and higher plasma density than conventional radio frequency (RF) plasma, it has a larger number of less energetic reaction species, such as radicals and ions. VHF PE-ALD Al2O3 shows superior physical and electrical properties over RF PE-ALD Al2O3, including high growth per cycle, excellent conformality, low roughness, high dielectric constant, low leakage current, and low interface trap density. In addition, interlayer-free Al2O3 on Si was achieved in VHF PE-ALD via a significant reduction in plasma damage. VHF PE-ALD will be an essential process to realize nanoscale devices that require precise control of interfaces and electrical properties.

  8. Modeling of neutral gas dynamics in high-density plasmas

    Science.gov (United States)

    Canupp, Patrick Wellington

    This thesis describes a physical model of chemically reactive neutral gas flow and discusses numerical solutions of this model for the flow in an inductively coupled plasma etch reactor. To obtain these solutions, this research develops an efficient, implicit numerical method. As a result of the enhanced numerical stability of the scheme, large time steps advance the solution from initial conditions to a final steady state in fewer iterations and with less computational expense than simpler explicit methods. This method would incorporate suitably as a module in currently existing large scale plasma simulation tools. In order to demonstrate the accuracy of the numerical technique, this thesis presents results from two simulations of flows that possess theoretical solutions. The first case is the inviscid flow of a gas through a converging nozzle. A comparison of the numerical solution to isentropic flow theory shows that the numerical technique capably captures the essential flow features of this environment. The second case is the Couette flow of a gas between two parallel plates. The simulation results compare well with the exact solution for this flow. After establishing the accuracy of the numerical technique, this thesis discusses results for the flow of chemically reactive gases in a chlorine plasma etch reactor. This research examines the influence of the plasma on the neutral gas and the dynamics exhibited by the neutral gas in the reactor. This research finds that the neutral gas temperature strongly depends on the rate at which inelastic, electron-impact dissociation reactions occur and on atomic chlorine wall recombination rates. Additionally, the neutral gas Aow in the reactor includes a significant mass flux of etch product from the wafer surface. Resolution of these effects is useful for neutral gas simulation. Finally, this thesis demonstrates that continuum fluid models provide reasonable accuracy for these low pressure reactor flows due to the fact

  9. High power, fast, microwave components based on beam generated plasmas

    Science.gov (United States)

    Manheimer, W. M.; Fernsler, R. F.; Gitlin, M. S.

    1998-10-01

    It is shown that the agile mirror plasma, under development as a device to simply and cheaply give electronic steering to microwave beams, also has application as a fast, electronically controlled, high power reflector, or phase shifter. In a radar system, this can lead to such applications as pulse to pulse polarization agility and electronic control of antenna gain, as well as to innovative approaches to high power millimeter wave circulators. The basic theory of the enhanced glow plasma is also developed.

  10. Sodium nitrite enhances generation of reactive oxygen species that decrease antioxidant power and inhibit plasma membrane redox system of human erythrocytes.

    Science.gov (United States)

    Ansari, Fariheen Aisha; Mahmood, Riaz

    2016-08-01

    Nitrite/nitrate salts are used in fertilizers and as food preservatives. Human exposure to high levels of nitrite results in its uptake and subsequent entry into blood where it can interact with erythrocytes. We show that treatment of human erythrocytes with sodium nitrite (NaNO2 ) results in a dose-dependent increase in the production of reactive oxygen species. This was accompanied by a decrease in the antioxidant power which lowered the free radical quenching and metal-reducing ability. NaNO2 treatment also inhibited plasma membrane redox system (PMRS) of erythrocytes. These changes increase the susceptibility of erythrocytes to oxidative damage, decrease the antioxidant power of whole blood, and can be a major cause of nitrite-induced cellular toxicity.

  11. High temperature UF6 RF plasma experiments applicable to uranium plasma core reactors

    Science.gov (United States)

    Roman, W. C.

    1979-01-01

    An investigation was conducted using a 1.2 MW RF induction heater facility to aid in developing the technology necessary for designing a self critical fissioning uranium plasma core reactor. Pure, high temperature uranium hexafluoride (UF6) was injected into an argon fluid mechanically confined, steady state, RF heated plasma while employing different exhaust systems and diagnostic techniques to simulate and investigate some potential characteristics of uranium plasma core nuclear reactors. The development of techniques and equipment for fluid mechanical confinement of RF heated uranium plasmas with a high density of uranium vapor within the plasma, while simultaneously minimizing deposition of uranium and uranium compounds on the test chamber peripheral wall, endwall surfaces, and primary exhaust ducts, is discussed. The material tests and handling techniques suitable for use with high temperature, high pressure, gaseous UF6 are described and the development of complementary diagnostic instrumentation and measurement techniques to characterize the uranium plasma, effluent exhaust gases, and residue deposited on the test chamber and exhaust system components is reported.

  12. Plasma undulator excited by high-order mode lasers

    Science.gov (United States)

    Wang, Jingwei; Rykovanov, Sergey

    2016-10-01

    A laser-created plasma undulator together with a laser-plasma accelerator makes it possible to construct an economical and extremely compact XFEL. However, the spectrum spread of the radiation from the current plasma undulators is too large for XFELs, because of the different values of strength parameters. The phase slippage between the electrons and the wakefield also limits the number of the electron oscillation cycles, thus reduces the performance of XFEL. Here we proposed a phase-locked plasma undulator created by high-order mode lasers. The modulating field is uniform along the transverse direction by choosing appropriate laser intensities of the modes, which enables all the electrons oscillate with the same strength parameter. The plasma density is tapered to lock the phase between the electrons and the wakefield, which signally increases the oscillation cycles. As a result, X-ray radiation with high brightness and narrow bandwidth is generated by injecting a high-energy electron beam into the novel plasma undulator. The beam loading limit indicates that the current of the electron beam could be hundreds of Ampere. These properties imply that such a plasma undulator may have great potential in compact XFELs. This work was supported by the Helmholtz Association (Young Investigator's Group No. VH-NG-1037).

  13. Variations in C-reactive protein, plasma free radicals and fibrinogen values in patients with osteoarthritis treated with Pycnogenol.

    Science.gov (United States)

    Belcaro, G; Cesarone, M R; Errichi, S; Zulli, C; Errichi, B M; Vinciguerra, G; Ledda, A; Di Renzo, A; Stuard, S; Dugall, M; Pellegrini, L; Gizzi, G; Ippolito, E; Ricci, A; Cacchio, M; Cipollone, G; Ruffini, I; Fano, F; Hosoi, M; Rohdewald, P

    2008-01-01

    In a previous, double-blind, placebo-controlled study we evaluated the efficacy of a 3-month treatment with Pycnogenol for 156 patients with osteoarthritis of the knee. Pycnogenol significantly decreased joint pain and improved joint function as evaluated using the WOMAC score and walking performance of patients on a treadmill. In this study, we further investigated the anti-inflammatory and antioxidant activity of Pycnogenol in a subset of the osteoarthritis patients presenting with elevated C-reactive protein (CRP) and plasma-free radicals. Elevated CRP levels have been suggested to be associated with disease progression in osteoarthritis. In our study, 29 subjects of the Pycnogenol group and 26 patients in the placebo group showed CRP levels higher than 3 mg/l at baseline. Comparison of blood specimens drawn at baseline and after 3-month treatment showed that Pycnogenol significantly decreased plasma free radicals to 70.1% of baseline values. Plasma CRP levels decreased from baseline 3.9 mg/l to 1.1 mg/l in the Pycnogenol group whereas the control group had initial values of 3.9 mg/l which decreased to 3.6 mg/l. The CRP decrease in the Pycnogenol was statistical significant as compared to the control group (P Pycnogenol. No significant changes for plasma free radicals, CRP and fibrinogen were found in the placebo-treated group. The decrease of systemic inflammatory markers suggests that Pycnogenol may exert anti-inflammatory activity in osteoarthritic joints and patients did not present with other ailments or infections. The nature of the anti-inflammatory effects of Pycnogenol with regard to CRP warrants further investigation.

  14. Physics of High Performance Dueterium-Tritium Plasmas in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, K. M.; White, R.; Wieland, R. M.; Williams, M.; Wilson, J. R.; Wong, K. L.; Wurden, G. A.; Batha, S.; Lamarche, P.; LeBlanc, B.; Levinton, F. M.; Beer, M.; Bell, M. G.; Bell, R. E.; Belov, A.; Fredrickson, E. D.; Fu, G. Y.; Furth, H. P.; Gorelenkov, N. N.; Krasilnikov, A. V.; Meade, D. M.; Medley, S. S.; Mika, R.; Mikkelsen, D. R.; Mirnov, S. V.; Schilling, G.; Schivell, J.; Schmidt, G. L.; Scott, S. D.; Semenov, I.; Berk, H.; Bernabei, S.; Bitter, M.; Breizman, B.; Dorland, W.; Phillips, P.; Bretz, N. L.; Budny, R.; Bush, C.E.; Grek, B.; Grisham, L. R.; Hammett, G. W.; Herrmann, H. W.; Herrmann, M.; Hill, K. W.; Hogan, G. R.; Hosea, J. C.

    1996-01-01

    During the past two years, deuterium-tritium (D-T) plasmas in the Tokamak Fusion Test Reactor (TFTR) have been used to study fusion power production,isotope effects associated with tritium fueling, and alpha-particle physics in several operational regimes. The peak fusion power has been increased to 10.7 MW in the supershot mode through the use of increased plasma current and toroidal magnetic field and extensive lithium wall conditioning. The high-internal-inductance (high -li) regime in TFTR has been extended in plasma current and has achieved 8.7 MW of fusion power. Studies of the effects of tritium on confinement have now been carried out in ohmic, NBI- and ICRF-heated L-mode and reversed-shear plasmas. In general, there is an enhancement in confinement time in D-T plasmas which is most pronounced in supershot and high-li discharges, weaker in L-mode plasmas with NBI and ICRF heating and smaller still in ohmic plasmas. In reversed-shear discharges with sufficient deuterium-NBI heating power, internal transport barriers have been observed to form, leading to enhanced confinement. Large decreases in the ion heat conductivity and particle transport are inferred within the transport barrier.It appears that higher heating power is required to trigger the formation of a transport barrier with D-T NBI and the isotope effect on energy confinement is nearly absent in these enhanced reverse-shear plasmas. Many alpha-particle physics issues have been studied in the various operating regimes including confinement of the alpha particles, their redistribution by sawteeth, and their loss due to MHD instabilities with low toroidal mode numbers. In weak-shear plasmas, alpha-particle destabilization of a toroidal Alfven eigenmode has been observed.

  15. Deposition of highly textured AlN thin films by reactive high power impulse magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Milena A. [Department of Solid State Electronics, Ångström Laboratory, Uppsala University, Box 534, SE-752 21 Uppsala, Sweden and School of Electrical and Computer Engineering, University of Campinas, CEP 13.083-852 Campinas-SP (Brazil); Törndahl, Tobias; Katardjiev, Ilia; Kubart, Tomas, E-mail: tomas.kubart@angstrom.uu.se [Department of Solid State Electronics, Ångström Laboratory, Uppsala University, Box 534, SE-752 21 Uppsala (Sweden)

    2015-03-15

    Aluminum nitride thin films were deposited by reactive high power impulse magnetron sputtering (HiPIMS) and pulsed direct-current on Si (100) and textured Mo substrates, where the same deposition conditions were used for both techniques. The films were characterized by x-ray diffraction and atomic force microscopy. The results show a pronounced improvement in the AlN crystalline texture for all films deposited by HiPIMS on Si. Already at room temperature, the HiPIMS films exhibited a strong preferred (002) orientation and at 400 °C, no contributions from other orientations were detected. Despite the low film thickness of only 200 nm, an ω-scan full width at half maximum value of 5.1° was achieved on Si. The results are attributed to the high ionization of sputtered material achieved in HiPIMS. On textured Mo, there was no significant difference between the deposition techniques.

  16. Enhancing CaP biomimetic growth on TiO2 cuboids nanoparticles via highly reactive facets.

    Science.gov (United States)

    Ruso, Juan M; Verdinelli, Valeria; Hassan, Natalia; Pieroni, Olga; Messina, Paula V

    2013-02-19

    Pure decahedral anatase TiO(2) particles with high content of reactive {001} facets were obtained from titanium(IV) tetrachloride (TiCl(4)) using a microemulsions droplet system at specific conditions as chemical microreactor. The product was systematically characterized by X-ray diffraction, field-emission scanning and transmission electron microscopy (FE-SEM, TEM), N(2) adsorption-desorption isotherms, FT-IR and UV-vis spectroscopy, and photoluminescence studies. The obtained cuboids around 90 nm in size have a uniform and dense surface morphology with a BET specific surface area of 11.91 m(2) g(-1) and a band gap energy (3.18 eV) slightly inferior to the anatase dominated by the less-reactive {101} surface (3.20 eV). The presence of reactive facets on titania anatase favors the biomimetic growth of amorphous tricalcium phosphate after the first day of immersion in simulated human plasma. The results presented here can facilitate and improve the integration of anchored implants and enhance the biological responses to the soft tissues.

  17. Reactive Spark Plasma Sintering and Mechanical Properties of Zirconium Diboride–Titanium Diboride Ultrahigh Temperature Ceramic Solid Solutions

    Directory of Open Access Journals (Sweden)

    Karthiselva N. S.

    2016-09-01

    Full Text Available Ultrahigh temperature ceramics (UHTCs such as diborides of zirconium, hafnium tantalum and their composites are considered to be the candidate materials for thermal protection systems of hypersonic vehicles due to their exceptional combination of physical, chemical and mechanical properties. A composite of ZrB2-TiB2 is expected to have better properties. In this study, an attempt has been made to fabricate ZrB2-TiB2 ceramics using mechanically activated elemental powders followed by reactive spark plasma sintering (RSPS at 1400 °C. Microstructure and phase analysis was carried out using X-ray diffractometer (XRD and electron microscopy to understand microstructure evolution. Fracture toughness and hardness were evaluated using indentation methods. Nanoindentation was used to measure elastic modulus. Compressive strength of the composites has been reported.

  18. Inductively-coupled-plasma reactive ion etching of single-crystal β-Ga2O3

    Science.gov (United States)

    Zhang, Liheng; Verma, Amit; (Grace Xing, Huili; Jena, Debdeep

    2017-03-01

    Dry etching behavior of unintentionally-doped (\\bar{2}01) β-Ga2O3 has been studied in a BCl3/Ar chemistry using inductively-coupled-plasma reactive ion etching (ICP-RIE). The effects of various etch parameters like ICP and RIE powers, BCl3/Ar gas ratio and chamber pressure on etch rate are studied systematically. Higher ICP, RIE powers and lower pressure conditions are found to enhance the etch rate. A synergic etching mechanism between chemical and physical components is proposed and used to obtain fast Ga2O3 etch rates more than 160 nm/min, nearly-vertical sidewalls and smooth etched surfaces. The findings of this work will enable Ga2O3 vertical devices for power electronics.

  19. Physics of high performance deuterium-tritium plasmas in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, K.M. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.; Barnes, C.W. [Los Alamos National Lab., NM (United States); Batha, S. [Fusion Physics and Technology, Torrance, CA (United States)] [and others

    1996-11-01

    During the past two years, deuterium-tritium (D-T) plasmas in the Tokamak Fusion Test Reactor (TFTR) have been used to study fusion power production, isotope effects associated with tritium fueling, and alpha-particle physics in several operational regimes. The peak fusion power has been increased to 10.7 MW in the supershot mode through the use of increased plasma current and toroidal magnetic field and extensive lithium wall conditioning. The high-internal-inductance (high-I{sub i}) regime in TFTR has been extended in plasma current and has achieved 8.7 MW of fusion power. Studies of the effects of tritium on confinement have now been carried out in ohmic, NBI- and ICRF- heated L-mode and reversed-shear plasmas. In general, there is an enhancement in confinement time in D-T plasmas which is most pronounced in supershot and high-I{sub i} discharges, weaker in L-mode plasmas with NBI and ICRF heating and smaller still in ohmic plasmas. In reversed-shear discharges with sufficient deuterium-NBI heating power, internal transport barriers have been observed to form, leading to enhanced confinement. Large decreases in the ion heat conductivity and particle transport are inferred within the transport barrier. It appears that higher heating power is required to trigger the formation of a transport barrier with D-T NBI and the isotope effect on energy confinement is nearly absent in these enhanced reverse-shear plasmas. Many alpha-particle physics issues have been studied in the various operating regimes including confinement of the alpha particles, their redistribution by sawteeth, and their loss due to MHD instabilities with low toroidal mode numbers. In weak-shear plasmas, alpha-particle destabilization of a toroidal Alfven eigenmode has been observed.

  20. Controlled fluoridation of amorphous carbon films deposited at reactive plasma conditions

    Directory of Open Access Journals (Sweden)

    Yoffe Alexander

    2015-09-01

    Full Text Available A study of the correlations between plasma parameters, gas ratios, and deposited amorphous carbon film properties is presented. The injection of a C4F8/Ar/N2 mixture of gases was successfully used in an inductively coupled plasma system for the preparation of amorphous carbon films with different fluoride doping at room-temperature, using silicon as a substrate. This coating was formed at low-pressure and low-energy using an inductively coupled plasma process. A strong dependence between the ratios of gases during deposition and the composition of the substrate compounds was shown. The values of ratios between Ar (or Ar+N2 and C4F8 - 1:1 and between N2 and Ar - 1:2 in the N2/Ar/C4F8 mixture were found as the best for low fluoridated coatings. In addition, an example of improving the etch-passivation in the Bosch procedure was described. Scanning electron microscopy with energy dispersive spectroscopy options, X-ray diffraction, and X-ray reflectivity were used for quantitative analysis of the deposited films.

  1. Interaction of High Intensity Electromagnetic Waves with Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    G. Shvets

    2008-10-03

    The focus of our work during the duration of this grant was on the following areas: (a) the fundamental plasma physics of intense laser-plasma interactions, including the nonlinear excitation of plasma waves for accelerator applications, as well as the recently discovered by us phenomenon of the relativistic bi-stability of relativistic plasma waves driven by a laser beatwave; (b) interaction of high power microwave beams with magnetized plasma, including some of the recently discovered by us phenomena such as the Undulator Induced Transparency (UIT) as well as the new approaches to dynamic manipulation of microwave pulses; (c) investigations of the multi-color laser pulse interactions in the plasma, including the recently discovered by us phenomenon of Electromagnetic Cascading (EC) and the effect of the EC of three-dimensional dynamics of laser pulses (enhanced/suppressed selffocusing etc.); (d) interaction of high-current electron beams with the ambient plasma in the context of Fast Ignitor (FI) physics, with the emphasis on the nonlinear dynamics of the Weibel instability and beam filamentation.

  2. Erosion behavior of composite Al-Cr cathodes in cathodic arc plasmas in inert and reactive atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Franz, Robert, E-mail: robert.franz@unileoben.ac.at; Mendez Martin, Francisca; Hawranek, Gerhard [Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700 Leoben (Austria); Polcik, Peter [Plansee Composite Materials GmbH, Siebenbürgerstrasse 23, 86983 Lechbruck am See (Germany)

    2016-03-15

    Al{sub x}Cr{sub 1−x} composite cathodes with Al contents of x = 0.75, 0.5, and 0.25 were exposed to cathodic arc plasmas in Ar, N{sub 2}, and O{sub 2} atmospheres and their erosion behavior was studied. Cross-sectional analysis of the elemental distribution of the near-surface zone in the cathodes by scanning electron microscopy revealed the formation of a modified layer for all cathodes and atmospheres. Due to intermixing of Al and Cr in the heat-affected zone, intermetallic Al-Cr phases formed as evidenced by x-ray diffraction analysis. Cathode poisoning effects in the reactive N{sub 2} and O{sub 2} atmospheres were nonuniform as a result of the applied magnetic field configuration. With the exception of oxide islands on Al-rich cathodes, reactive layers were absent in the circular erosion zone, while nitrides and oxides formed in the less eroded center region of the cathodes.

  3. Acute plasma volume change with high-intensity sprint exercise.

    Science.gov (United States)

    Bloomer, Richard J; Farney, Tyler M

    2013-10-01

    When exercise is of long duration or of moderate to high intensity, a decrease in plasma volume can be observed. This has been noted for both aerobic and resistance exercise, but few data are available with regard to high-intensity sprint exercise. We measured plasma volume before and after 3 different bouts of acute exercise, of varying intensity, and/or duration. On different days, men (n = 12; 21-35 years) performed aerobic cycle exercise (60 minutes at 70% heart rate reserve) and 2 different bouts of cycle sprints (five 60-second sprints at 100% maximum wattage obtained during graded exercise testing (GXT) and ten 15-second sprints at 200% maximum wattage obtained during GXT). Blood was collected before and 0, 30, and 60 minutes postexercise and analyzed for hematocrit and hemoglobin and plasma volume was calculated. Plasma volume decreased significantly for all exercise bouts (p sprint bouts (∼19%) compared with aerobic exercise bouts (∼11%). By 30 minutes postexercise, plasma volume approached pre-exercise values. We conclude that acute bouts of exercise, in particular high-intensity sprint exercise, significantly decrease plasma volume during the immediate postexercise period. It is unknown what, if any negative implications these transient changes may have on exercise performance. Strength and conditioning professionals may aim to rehydrate athletes appropriately after high-intensity exercise bouts.

  4. Mechanism of flue gas simultaneous desulfurization and denitrification using the highly reactive absorbent

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yi; SUN Xiaojun; XU Peiyao; MA Shuangchen; WANG Lidong; LIU Feng

    2005-01-01

    Fly ash, industry-grade lime and a few oxidizing manganese compound additive were used to prepare the "Oxygen-riched" highly reactive absorbent for simultaneous desulfurization and denitrification. Experiments of simultaneous desulfurization and denitrification were carried out using the highly reactive absorbent in the flue gas circulating fluidized bed (CFB) system. Removal efficiencies of 94.5% for SO2 and 64.2% for NO were obtained respectively. The scanning electron microscope (SEM) and accessory X-ray energy spectrometer were used to observe micro-properties of the samples, including fly ash, common highly reactive absorbent, "Oxygen-riched" highly reactive absorbent and spent absorbent. The white flake layers were observed in the SEM images about surfaces of the common highly reactive absorbent and "Oxygen- riched" one, and the particle surfaces of the spent absorbent were porous. The content of calcium on surface was higher than that of the average in the highly reactive absorbent. The manganese compound additive dispersed uniformly on the surfaces of the "Oxygen- riched" highly reactive absorbent. There was a sulfur peak in the energy spectra pictures of the spent absorbent. The component of the spent absorbent was analyzed with chemical analysis methods, and the results indicated that more nitrogen species appeared in the absorbent except sulfur species, and SO2 and NO were removed by chemical absorption according to the experimental results of X-ray energy spectrometer and the chemical analysis. Sulfate being the main desulfurization products, nitrite was the main denitrification ones during the process, in which NO was oxidized rapidly to NO2 and absorbed by the chemical reaction.

  5. High-fidelity plasma codes for burn physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooley, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Graziani, Frank [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marinak, Marty [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murillo, Michael [Michigan State Univ., East Lansing, MI (United States)

    2016-10-19

    Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiation-hydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of self-heating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes, are a relatively recent computational tool that augments both experimental data and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.

  6. Ultra-High Intensity Magnetic Field Generation in Dense Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, Nathaniel J. [Princeton Univ., NJ (United States)

    2014-01-08

    The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereas the efficient generation of electric current in low-­energy-­density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­energy-­density plasma the ideas for steady-­state current drive developed for low-­energy-­density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­energy-­density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.

  7. High-fidelity plasma codes for burn physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooley, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Graziani, Frank [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Marinak, Marty [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murillo, Michael [Michigan State Univ., East Lansing, MI (United States)

    2016-10-19

    Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiationhydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of selfheating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes are a relatively recent computational tool that augments both experimental data and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.

  8. The high flux plasma generator Magnum-PSI

    Science.gov (United States)

    van Eck, H. J. N.; Kleyn, A. W.; Koppers, W. R.; Rapp, J.; Zeijlmans van Emmichoven, P. A.

    2010-11-01

    Magnum-PSI is a magnetized (3 T), high-flux (up to 10^24 H^+ ions m-2s-1) plasma generator, capable of delivering 10 MW m-2 steady-state power fluxes to a large area target. Magnum-PSI is a highly accessible laboratory experiment in which the interaction of magnetized plasma with different surfaces can be studied. This experiment will provide new insights in the complex physics and chemistry that will occur in the divertor region of the future experimental fusion reactor ITER and reactors beyond ITER. In this contribution, we will present the design and characterization of the Magnum-PSI experiment. The differentially pumped vacuum system, the superconducting magnet, the plasma source, the target plate and manipulator will be presented. Simulations and measurements of the neutral gas flow, as well as electron density and temperature measurements of the plasma beam will be presented. Furthermore, a flavor of upcoming PSI experiments will be given.

  9. Ultra-High Intensity Magnetic Field Generation in Dense Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, Nathaniel J

    2014-01-08

    I. Grant Objective The main objective of this grant proposal was to explore the efficient generation of intense currents. Whereasthefficient generation of electric current in low-­energy-­density plasma has occupied the attention of the magnetic fusion community for several decades, scant attention has been paid to carrying over to high-­energy-­density plasma the ideas for steady-­state current drive developed for low-­energy-­density plasma, or, for that matter, to inventing new methodologies for generating electric current in high-­energy-­density plasma. What we proposed to do was to identify new mechanisms to accomplish current generation, and to assess the operation, physics, and engineering basis of new forms of current drive in regimes appropriate for new fusion concepts.

  10. Plasma-puff initiation of high Coulomb transfer switches

    Science.gov (United States)

    Han, Kwang S.; Venable, Demetrius D.; Lee, Ja H.; Choi, Eun H.; Kim, Y. K.; Kim, J. H.; Nguyen, D. X.

    1993-01-01

    The plasma-puff triggering mechanism based on a hypocycloidal pinch geometry was investigated to determine the optimal operating conditions for an azimuthally uniform surface flashover which initiates plasma-puff under wide ranges of fill gas pressures of Ar, He and N2. The optimal fill gas pressures for the azimuthally uniform plasma-puff were about 120 mTorr less than P(sub opt) less than 450 Torr for He and N2. For Argon 20 mTorr is less than P(sub opt) is less than 5 Torr. The inverse pinch switch was triggered with the plasma-puff and the switching capability under various electrical parameters and working gas pressures of Ar, He and N2 was determined. It was also shown that the azimuthally uniform switching discharges were dependent on the type of fill gas and its fill pressure. A new concept of plasma-focus driven plasma-puff was also discussed in comparison with hypocycloidal pinch plasma-puff triggering. The main discharge of the inverse pinch switch with the plasma-focus driven plasma-puff trigger is found to be more azimuthally uniform than that with the hypocycloidal pinch plasma-puff trigger in a gas pressure region between 80 mTorr and 1 Torr. In order to assess the effects of plasma current density on material erosion of electrodes, emissions from both an inverse-pinch plasma switch (INPIStron) and from a spark gap switch under test were studied with an optical multichannel analyzer (OMA). The color temperature of the argon plasma was approximately 4,000 K which corresponded with the peak continuum emission near 750 nm. There are the strong line emissions of argon in the 650 - 800 nm range and a lack of line emissions of copper and other solid material used in the switch. This indicates that the plasma current density during closing is low and the hot spot or hot filament in the switch is negligible. This result also indicates considerable reduction of line emission with the INPIStron switch over that of a spark-gap switch. However, a strong carbon

  11. Study of Volumetrically Heated Ultra-High Energy Density Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Rocca, Jorge J. [Colorado State Univ., Fort Collins, CO (United States)

    2016-10-27

    Heating dense matter to millions of degrees is important for applications, but requires complex and expensive methods. The major goal of the project was to demonstrate using a compact laser the creation of a new ultra-high energy density plasma regime characterized by simultaneous extremely high temperature and high density, and to study it combining experimental measurements and advanced simulations. We have demonstrated that trapping of intense femtosecond laser pulses deep within ordered nanowire arrays can heat near solid density matter into a new ultra hot plasma regime. Extreme electron densities, and temperatures of several tens of million degrees were achieved using laser pulses of only 0.5 J energy from a compact laser. Our x-ray spectra and simulations showed that extremely highly ionized plasma volumes several micrometers in depth are generated by irradiation of gold and Nickel nanowire arrays with femtosecond laser pulses of relativistic intensities. We obtained extraordinarily high degrees of ionization (e.g. we peeled 52 electrons from gold atoms, and up to 26 electrons from nickel atoms). In the process we generated Gigabar pressures only exceeded in the central hot spot of highly compressed thermonuclear fusion plasmas.. The plasma created after the dissolved wires expand, collide, and thermalize, is computed to have a thermal energy density of 0.3 GJ cm-3 and a pressure of 1-2 Gigabar. These are pressures only exceeded in highly compressed thermonuclear fusion plasmas. Scaling these results to higher laser intensities promises to create plasmas with temperatures and pressures exceeding those in the center of the sun.

  12. Development of chiral metal amides as highly reactive catalysts for asymmetric [3 + 2] cycloadditions

    Science.gov (United States)

    Yamashita, Yasuhiro; Yoshimoto, Susumu; Dutton, Mark J

    2016-01-01

    Summary Highly efficient catalytic asymmetric [3 + 2] cycloadditions using a chiral copper amide are reported. Compared with the chiral CuOTf/Et3N system, the CuHMDS system showed higher reactivity, and the desired reactions proceeded in high yields and high selectivities with catalyst loadings as low as 0.01 mol %. PMID:27559396

  13. Plasma Interaction with International Space Station High Voltage Solar Arrays

    Science.gov (United States)

    Heard, John W.

    2002-01-01

    The International Space Station (ISS) is presently being assembled in low-earth orbit (LEO) operating high voltage solar arrays (-160 V max, -140 V typical with respect to the ambient atmosphere). At the station's present altitude, there exists substantial ambient plasma that can interact with the solar arrays. The biasing of an object to an electric potential immersed in plasma creates a plasma "sheath" or non-equilibrium plasma around the object to mask out the electric fields. A positively biased object can collect electrons from the plasma sheath and the sheath will draw a current from the surrounding plasma. This parasitic current can enter the solar cells and effectively "short out" the potential across the cells, reducing the power that can be generated by the panels. Predictions of collected current based on previous high voltage experiments (SAMPIE (Solar Array Module Plasma Interactions Experiment), PASP+ (Photovoltaic Array Space Power) were on the order of amperes of current. However, present measurements of parasitic current are on the order of several milliamperes, and the current collection mainly occurs during an "eclipse exit" event, i.e., when the space station comes out of darkness. This collection also has a time scale, t approx. 1000 s, that is much slower than any known plasma interaction time scales. The reason for the discrepancy between predictions and present electron collection is not understood and is under investigation by the PCU (Plasma Contactor Unit) "Tiger" team. This paper will examine the potential structure within and around the solar arrays, and the possible causes and reasons for the electron collection of the array.

  14. Numerical Studies of High-Z Plasma in the HyperV Plasma Guns

    Science.gov (United States)

    Wu, Linchun; Messer, Sarah; Witherspoon, F. Douglas; Welch, Dale; Thoma, Carsten; Phillips, Mike; Bogatu, I. Nick; Galkin, Sergei; Macfarlane, Joe; Golovkin, Igor

    2010-11-01

    Numerical studies of railguns and coaxial guns at HyperV Technologies Corp. include simulations of hypervelocity plasma transport in the gun, plasma expansion out of the nozzle, and two or more jets merging in vacuum. Plasma detachment, merging jets temperature and charge state evolution are examined in these processes. High-Z materials, such as argon and xenon, are used throughout these simulations. The plasma moves with an initial velocity of 0-10 km/s (80-100 km/s for jet merging), the initial number density ranges from 10^15cm-3 to 10^18cm-3, and the merging jets are several centimeters in radius. The LSP code is used to perform the simulations using improved fluid algorithms and equation-of-state models from Voss and atomic data from Prism.

  15. Downstream plasma transport and metal ionization in a high-powered pulsed-plasma magnetron

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Liang; Szott, Matthew M.; McLain, Jake T.; Ruzic, David N. [Center for Plasma-Materials Interactions, Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Yu, He [Center for Plasma-Materials Interactions, Department of Nuclear, Plasma, and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2014-06-14

    Downstream plasma transport and ionization processes in a high-powered pulsed-plasma magnetron were studied. The temporal evolution and spatial distribution of electron density (n{sub e}) and temperature (T{sub e}) were characterized with a 3D scanning triple Langmuir probe. Plasma expanded from the racetrack region into the downstream region, where a high n{sub e} peak was formed some time into the pulse-off period. The expansion speed and directionality towards the substrate increased with a stronger magnetic field (B), largely as a consequence of a larger potential drop in the bulk plasma region during a relatively slower sheath formation. The fraction of Cu ions in the deposition flux was measured on the substrate using a gridded energy analyzer. It increased with higher pulse voltage. With increased B field from 200 to 800 Gauss above racetrack, n{sub e} increased but the Cu ion fraction decreased from 42% to 16%. A comprehensive model was built, including the diffusion of as-sputtered Cu flux, the Cu ionization in the entire plasma region using the mapped n{sub e} and T{sub e} data, and ion extraction efficiency based on the measured plasma potential (V{sub p}) distribution. The calculations matched the measurements and indicated the main causes of lower Cu ion fractions in stronger B fields to be the lower T{sub e} and inefficient ion extraction in a larger pre-sheath potential.

  16. High energy density Z-pinch plasmas using flow stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Shumlak, U., E-mail: shumlak@uw.edu; Golingo, R. P., E-mail: shumlak@uw.edu; Nelson, B. A., E-mail: shumlak@uw.edu; Bowers, C. A., E-mail: shumlak@uw.edu; Doty, S. A., E-mail: shumlak@uw.edu; Forbes, E. G., E-mail: shumlak@uw.edu; Hughes, M. C., E-mail: shumlak@uw.edu; Kim, B., E-mail: shumlak@uw.edu; Knecht, S. D., E-mail: shumlak@uw.edu; Lambert, K. K., E-mail: shumlak@uw.edu; Lowrie, W., E-mail: shumlak@uw.edu; Ross, M. P., E-mail: shumlak@uw.edu; Weed, J. R., E-mail: shumlak@uw.edu [Aerospace and Energetics Research Program, University of Washington, Seattle, Washington, 98195-2250 (United States)

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

  17. Microstructure and performance of reactive plasma clad high chromium iron based ceramic reinforcing wear-resistance coating%反应等离子熔覆高铬铁基金属陶瓷增强耐磨涂层组织与性能

    Institute of Scientific and Technical Information of China (English)

    王立梅

    2011-01-01

    利用反应等离子熔覆技术、以Fe-Cr-C-W-Ni合金粉末为原料,在Q235钢表面制得了Cr7C3高铬铁基金属陶瓷增强耐磨复合涂层.利用SEM、EDS和X射线衍射分析了涂层的显微组织,在室温干滑动磨损试验条件下测试了涂层的耐磨性.结果表明:反应等离子熔覆CE7C3高铬铁基金属陶瓷增强耐磨复合涂层硬度高、组织均匀、与基材之间为完全冶金结合;涂层在室温干滑动磨损试验条件下表现出优异的耐磨性,涂层磨损的质量损失随载荷增加十分缓慢,涂层具有优异的载荷特性.%A wear resistant high chromium iron based ceramic reinforcing wear-resistance coating was fabricated on substrate of a Q235 steel by plasma cladding using the Fe-Cr-C-W-Ni alloy powders. Microstructure of the coating was characterized by OM, SEM, EDS and XRD. Wear resistance of the coating was tested under dry sliding wear condition at room temperature. Results indicate that the plasma clad high chromium iron based ceramic reinforced wear-resistance composite coating has a rapidly solidified homogeneous microstructure consisting of Cr7C3 ceramal primary particles uniformly distributed in the Cr7C3/γ-Fe eutectic matrix and is metallurgically bonded to the Q235 steel substrate. The plasma clad composite coating has high hardness and excellent wear resistance under dry sliding wear test conditions. Wear mass loss of the coating is increased slowly with the load increased and it has excellent load characteristic.

  18. Development of a widely applicable immunoassay for insulin in marine teleosts that regulates cross-reactivity using biotinylation and inhibits interference by plasma components.

    Science.gov (United States)

    Andoh, Tadashi

    2016-01-15

    Amino acids are important insulinotropins in fish, and their effects vary between amino acids and fish species. Insulin levels are indicative of growth efficiency and stress levels in fish; however, interspecies comparisons of insulin levels are hampered by the difficulty of measuring insulin concentration in each fish. We developed a widely applicable competitive immunoassay using biotinylated yellowtail (Seriola quinqueradiata) insulin for measuring insulin in marine teleosts, including yellowtail and red seabream (Pagrus major), which are the most common species raised by aquaculture in Japan. Amino acid sequence substitution was limited at the ninth residue of the A-chain (A9) between these two species, and analysis of the primary structures of insulins from six phylogenetically far teleosts suggested that the sequences of yellowtail and red seabream insulins are identical to those of many teleosts, except the A9 residue. However, A9 is known to be an epitope that confers cross-reactive differences on insulin. We solved this problem through immunoreactive invalidation of this residue by biotinylation. The binding-inhibition curves of yellowtail and red seabream insulins were identical following the use of this technique. However, yellowtail and red seabream plasma was found to contain components that interfere with immunoassays. This problem was solved by the extraction of plasma using equal volume of acid-ethanol in yellowtail and by cooling at 0°C during the cross-reaction between the ligand and antibody in red seabream. Serially diluted plasma samples from both species exhibited linearity after these treatments. In a recovery test using plasma with added yellowtail insulin, the average recovery varied from 96.2% to 109.4%. A post-feeding rise in insulin was confirmed by this immunoassay in yellowtail, and peak of the rise was 39.8±7ng/ml at 1h postfeeding from 3.9±1.1ng/ml at 0h. This indicates that this assay is sufficient for measuring the baseline

  19. Comparison of C-reactive protein and high-sensitivity C-reactive protein levels in patients on hemodialysis

    Directory of Open Access Journals (Sweden)

    Imed Helal

    2012-01-01

    Full Text Available Chronic inflammation is highly prevalent in patients on hemodialysis (HD, as evidenced by increased levels of C-reactive protein (CRP. We compared CRP to high-sensitivity C-reactive protein (hs-CRP to determine whether it has any clinical implications and prognostic significance in terms of mortality. CRP was measured using a standard immunoturbidometric assay on the COBAS; INTEGRA system and hs-CRP was measured using the Dade Behring on the Konelab Nephelometer in 50 patients on HD. CRP (≥6 mg/L and hs-CRP (≥3 mg/L levels were elevated in 30% and 54% of the patients, respectively. A significant correlation was noted between hs-CRP and CRP levels (r = 0.98, P <0.001. Deming regression analysis showed that the slope was near one (r = 0.90; 0.83-0.94 and that the intercept was small. Multivariate regression confirmed that age above 40 years (RR = 3.69, P = 0.027 and duration on HD greater than five years (RR = 3.71, P = 0.028 remained significant independent predictors of serum hs-CRP. Thirteen patients died during follow-up (26%. Multivariate Cox regression demonstrated that hs-CRP (RR = 1.062, P = 0.03 and CRP levels (RR = 1.057, P = 0.009 and age (RR = 1.078, P = 0.001 were the most powerful predictors of mortality. The CRP standard assay presents a reasonable alternative to the hs-CRP assay in patients on HD. The advantages of the CRP standard assay are its online and real-time availability as well as lower costs, particularly in developing countries.

  20. Comparison of C-reactive protein and high-sensitivity C-reactive protein levels in patients on hemodialysis.

    Science.gov (United States)

    Helal, Imed; Zerelli, Lilia; Krid, Madiha; ElYounsi, Fethi; Ben Maiz, Hedi; Zouari, Bechir; Adelmoula, Jaouida; Kheder, Adel

    2012-05-01

    Chronic inflammation is highly prevalent in patients on hemodialysis (HD), as evidenced by increased levels of C-reactive protein (CRP). We compared CRP to high-sensitivity C-reactive protein (hs-CRP) to determine whether it has any clinical implications and prognostic significance in terms of mortality. CRP was measured using a standard immunoturbidometric assay on the COBAS® INTEGRA system and hs-CRP was measured using the Dade Behring on the Konelab Nephelometer in 50 patients on HD. CRP (≥6 mg/L) and hs-CRP (≥3 mg/L) levels were elevated in 30% and 54% of the patients, respectively. A significant correlation was noted between hs-CRP and CRP levels (r = 0.98, P <0.001). Deming regression analysis showed that the slope was near one (r = 0.90; 0.83-0.94) and that the intercept was small. Multivariate regression confirmed that age above 40 years (RR = 3.69, P = 0.027) and duration on HD greater than five years (RR = 3.71, P = 0.028) remained significant independent predictors of serum hs-CRP. Thirteen patients died during follow-up (26%). Multivariate Cox regression demonstrated that hs-CRP (RR = 1.062, P = 0.03) and CRP levels (RR = 1.057, P = 0.009) and age (RR = 1.078, P = 0.001) were the most powerful predictors of mortality. The CRP standard assay presents a reasonable alternative to the hs-CRP assay in patients on HD. The advantages of the CRP standard assay are its online and real-time availability as well as lower costs, particularly in developing countries.

  1. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL

    2011-01-01

    Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.

  2. Fundamental processes of plasma and reactive gas surface treatment for the recovery of hydrogen isotopes from carbon co-deposits in fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Soeren

    2014-11-01

    The use of carbon-based plasma-facing wall components offers many advantages for plasma operation in magnetic confinement nuclear fusion devices. However, through reactions with the hydrogen based fusion plasma, carbon forms amorphous hydrogenated carbon co-deposits (a-C:H) in the vacuum vessels. If tritium is used to fuel the reactor, this co-deposition can quickly lead to an inacceptable high tritium inventory. Through co-deposition with carbon about 10% of the tritium injected into the reactor can be trapped. Even with other wall materials co-deposition can be significant. A method to recover the hydrogen isotopes from the co-deposits is necessary. The method has to be compatible with the requirements of the devices and nuclear fusion plasma operation. In this work thermo-chemical removal by neutral gases (TCR) and removal by plasmas is investigated. Models are developed to describe the involved processes of both removal methods. TCR is described using a reaction-diffusion model. Within this model the reactive gas diffuses into the co-deposits and subsequently reacts in a thermally activated process. The co-deposits are pyrolysed, forming volatile gases, e.g. CO{sub 2} and H{sub 2}O. These gases are pumped from the vacuum vessel and recycled. Applying the model to literature observations enables to connect data on exposure temperature, pressure, time and co-deposit properties. Two limits of TCR (reaction- or diffusion-limited) are identified. Plasma removal sputters co-deposits by their chemical and physical interaction with the impinging ions. The description uses a 0D plasma model from the literature which derives plasma parameters from the balance of input power to plasma power losses. The model is extended with descriptions of the plasma sheath and ion-surface interactions to derive the co-deposit removal rates. Plasma removal can be limited by this ion induced surface release rate or the rate of pumping of the released species. To test the models dedicated

  3. The influence of N2 flow rate on Ar and Ti Emission in high-pressure magnetron sputtering system plasma

    Science.gov (United States)

    How, Soo Ren; Nayan, Nafarizal; Lias, Jais

    2017-03-01

    For ionized physical vapor deposition (known as IPVD) technique, investigation on the ionization mechanism of titanium atoms is very important during the deposition of titanium nitride (TiN) thin film using reactive magnetron sputtering plasma. The introduction of nitrogen gas into the chamber discharge leads to modifications of plasma parameters and ionization mechanism of transition species. In this work, an investigation on the influence of nitrogen flow rate on spectrum properties of argon and titanium during the deposition process have been carried out. The experimental configuration consists of OES and structure of magnetron sputtering device with the turbo molecular pump. A high-pressure magnetron sputtering plasma was used as plasma discharge chamber with various flow rate of nitrogen gas. Optical emission spectroscopy (OES) measurements were employed as plasma diagnostics tool in magnetron sputtering plasma operated at relatively high pressure. OES is a non-invasive plasma diagnostics method and that can detect the atomic and ionic emission during plasma discharge. The flow rate of the Ar and N2 gas are controlled by mass flow controller. The changes of relative emission for both neutral and ionic of argon as well as titanium were observed using optical spectrometer when the nitrogen gas is introduced into the discharged chamber. We found that the titanium emission decreased very rapidly with the flow rate of nitrogen. In addition, the argon emission slightly decreased with the flow rate of nitrogen.

  4. Application possibilities of plasmas generated by high power laser ablation

    OpenAIRE

    Torrisi, L.

    2009-01-01

    High-power pulsed lasers emitting IR and visible radiation with intensities ranging between 10^8 and 10^16 W/cm2, pulse duration from 0.4 to 9 ns and energy from 100 mJ up to 600 J, operating in single mode or in repetition rate, can be employed to produce non-equilibrium plasma in vacuum by irradiating solid targets. Such a laser-produced plasma generates highly charged and high-energy ions of various elements, as well as soft and hard X-ray radiations. Heavy ions with charge state up to 58+...

  5. A highly reliable trigger for vacuum ARC plasma source

    Energy Technology Data Exchange (ETDEWEB)

    Bernardet, H.; Godechot, X.; Jarjat, F. [SODERN, Limeil-Brevannes (France)

    1996-08-01

    The authors have developed a reliable electrical trigger and its associated circuitry to fire vacuum arc plasma or ion source. They tested different embodiments of the trigger device in order to get a highly reliable one, which is able to perform more than 1.2 x 10{sup 6} shots at 60 A and 6.5 ps pulse length. The evolution of the ion current emitted has been recorded as a function of the number of shots. They have also investigated in which direction the plasma jet is emitted : axially or radially. This device can be used to fire a vacuum arc plasma or ion source by plasma injection. It has obvious advantage to be placed outside the cathode and therefore would ease maintenance of vacuum arc devices.

  6. Plasma effect on the phase matching of high harmonic generation

    Institute of Scientific and Technical Information of China (English)

    Hui Lu; Candong Liu; Shitong Zhao; Peng Liu

    2011-01-01

    By optimizing the phase matching condition of high harmonic generation (HHG) from a supersonic neon gas jet, the enhanced HHG in the region of 60-70 eV has been selected. Three-dimensional numerical calculation shows that plasma plays a significant role in the phase matching process of HHG in a supersonic gas jet with short medium length. Due to plasma formation, the harmonic emission decays as the laser intensity reaches over 3.5 × 1014 W/cm2. The plasma induces the broadening and blue shift of the HHG spectra, which provides a method for fine-tuning the harmonic wavelength.%@@ By optimizing the phase matching condition of high harmonic generation (HHG) from a supersonic neon gas jet, the enhanced HHG in the region of 60-70 eV has been selected. Three-dimensional numerical calculation shows that plasma plays a significant role in the phase matching process of HHG in a supersonic gas jet with short medium length. Due to plasma formation, the harmonic emission decays as the laser intensity reaches over 3.5 × 1014 W/cm2. The plasma induces the broadening and blue shift of the HHG spectra, which provides a method for fine-tuning the harmonic wavelength.

  7. 急性心肌梗死患者血浆超敏C-反应蛋白、纤维蛋白原及D-二聚体联合心肌损伤标志物的测定%The determination of plasma high sensitive C-reactive protein,fibrinogen and D-dimer combined with myocardial damage markers in patients with acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    蒋灵霓; 顾永林; 李宇林; 夏红安

    2015-01-01

    Objective To discuss the clinical value of high sensitivity C‐reactive protein(hs‐CRP) ,fibrinogen(Fib) and D‐dimer (D‐D) measurement for patients with acute myocardial infarction(AMI) before and after the treatment with the anticoagulation and thrombolysis therapy .Methods 110 patients with AMI were recruited in the study and the plasma hs‐CRP ,Fib ,D‐D and myocardi‐al damage markers were measured before and after the treatment .Results 66 of the 110 patients′plasma hs‐CRP ,Fib ,D‐D concen‐trations elevated(higher than the threshold) before treatment and after treatment within 24 h ,while 44 patients′plasma hs‐CRP , Fib concentrations increased ,but D‐D didn′t .Conclusion The measurement of hs‐CRP is helpful for the diagnosis and treatment of AMI .Hs‐CRP is another good myocardial injury marker ,and the plasma hs‐CRP concentration after treatment for 24 -48 h could reflect the severity and prognosis of AMI better than after treatment within 12 h .Fib decreases relatively slowly after the treat‐ment ,so it cannot be used for curative effect observation for AMI patients;D‐D concentration dosen′t have the determined negative predictive value for the diagnosis of AMI ,so it cannot be used as screening out indicator for AMI ,but D‐D concentration can be used as therapeutic effect monitoring indicator for AMI patients with D‐D positive .%目的:探讨急性心肌梗死(AMI)患者接受抗凝和溶栓治疗前后,超敏C反应蛋白(hs‐CRP)、纤维蛋白原(Fib)、D‐二聚体(D‐D)检测的临床价值。方法选取于该院心内科住院的110例AMI患者,分别在治疗前后测定其血浆hs‐CRP、Fib、D‐D及心肌损伤标志物水平。结果110例AMI患者中66例患者治疗前及治疗至24 h血浆中hs‐CRP、Fib、D‐D水平均升高(高于阈值);44例患者治疗前及治疗至24 h血浆中的hs‐CRP和Fib水平升高,而D‐D不升高。结论 hs

  8. High pro-inflammatory cytokine secretion and loss of high avidity cross-reactive cytotoxic T-cells during the course of secondary dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Tao Dong

    Full Text Available BACKGROUND: Dengue is one of the most important human diseases transmitted by an arthropod vector and the incidence of dengue virus infection has been increasing - over half the world's population now live in areas at risk of infection. Most infections are asymptomatic, but a subset of patients experience a potentially fatal shock syndrome characterised by plasma leakage. Severe forms of dengue are epidemiologically associated with repeated infection by more than one of the four dengue virus serotypes. Generally attributed to the phenomenon of antibody-dependent enhancement, recent observations indicate that T-cells may also influence disease phenotype. METHODS AND FINDINGS: Virus-specific cytotoxic T lymphocytes (CTL showing high level cross reactivity between dengue serotypes could be expanded from blood samples taken during the acute phase of secondary dengue infection. These could not be detected in convalescence when only CTL populations demonstrating significant serotype specificity were identified. Dengue cross-reactive CTL clones derived from these patients were of higher avidity than serotype-specific clones and produced much higher levels of both type 1 and certain type 2 cytokines, many previously implicated in dengue pathogenesis. CONCLUSION: Dengue serotype cross-reactive CTL clones showing high avidity for antigen produce higher levels of inflammatory cytokines than serotype-specific clones. That such cells cannot be expanded from convalescent samples suggests that they may be depleted, perhaps as a consequence of activation-induced cell death. Such high avidity cross-reactive memory CTL may produce inflammatory cytokines during the course of secondary infection, contributing to the pathogenesis of vascular leak. These cells appear to be subsequently deleted leaving a more serotype-specific memory CTL pool. Further studies are needed to relate these cellular observations to disease phenotype in a large group of patients. If

  9. Developing high-performance concrete incorporating highly-reactive rice husk ash

    Directory of Open Access Journals (Sweden)

    Andrés Salas

    2012-10-01

    Full Text Available The aim of this study is to present results of an investigation about the developing of a highperformance concrete (HPC using a highly reactive pozzolan made from chemically treated rice husk ash (ChRHA prepared by a chemical-thermal attack to the rice husk. This particular rice husk ash (RHA consists of 99% of silica, highly amorphous, white in color and of greater pozzolanic activity than the silica fume and another rice husk ash prepared with only by a thermal treatment. The results of the physical, chemical and mineralogical characteristics of ChRHA are analyzed. In this study, the compressive strength, flexural strength, water absorption, resistance to carbonation, total charge-passed derived from rapid chloride permeability test (RCPT and modulus of elasticity of hardened concrete were determined in the laboratory. Test results indicate that it is possible to produce HPC with the incorporation the chemically treated RHA. The incorporation of the chemically treated rice husk ash into the concrete enhances the compressive strengthand the durability properties being comparable to the properties of high performance concretes with silica fume (SF made with the same replacement levels.

  10. Cognitive response to a cold pressor challenge in high and low blood pressure reactive subjects.

    Science.gov (United States)

    Heiden, L A; Larkin, K T; Knowlton, G E

    1991-01-01

    To examine the relationship between cognitive and cardiovascular reactions to a cold pressor challenge, 20 high and 20 low blood-pressure-reactive males were identified. Subjects were trained using a think-aloud procedure and asked to report their thoughts aloud during task presentation. In comparison to low-reactors, high-reactive subjects exhibited greater increases in systolic and diastolic blood pressure, but not heart rate, in response to the task. High-reactive subjects reported fewer distracting self-statements than low-reactors during the task. No group differences in positive, neutral, or negative self-statements were observed. These findings corroborate the importance of distraction strategies in mediating acute cardiovascular reactions to stress.

  11. Genetic variation in estrogen receptor, C-reactive protein and fibrinogen does not predict the plasma levels of inflammation markers after longterm hormone replacement therapy

    DEFF Research Database (Denmark)

    de Maat, Moniek P M; Madsen, Jonna Skov; Langdahl, Bente

    2007-01-01

    Markers of inflammation, such as C-reactive protein (CRP) and fibrinogen, are associated with the risk of atherothrombosis. Plasma levels of these markers of inflammation are affected by hormone replacement therapy (HRT) and modulated by smoking. We studied whether genetic variation in the estrogen......). The effect of HRT, smoking and genetic variations in ESR1 (PvuII and XbaI), CRP (1444C/T) and fibrinogen-beta (FGB, -455G/A) were determined. The plasma concentration of CRP was higher in the HRT group than in the control group (2.03 mg/l and 1.41 mg/l, respectively; p ... concentration (n.s.). Genetic polymorphisms in ESR1, CRP and fibrinogen were not associated with an effect of HRT on the CRP and fibrinogen plasma levels, and no significant interaction with smoking was observed. In conclusion, higher plasma levels of CRP and lower plasma levels of fibrinogen were observed...

  12. A high sensitivity momentum flux measuring instrument for plasma thruster exhausts and diffusive plasmas

    Energy Technology Data Exchange (ETDEWEB)

    West, Michael D.; Charles, Christine; Boswell, Rod W. [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2009-05-15

    A high sensitivity momentum flux measuring instrument based on a compound pendulum has been developed for use with electric propulsion devices and radio frequency driven plasmas. A laser displacement system, which builds upon techniques used by the materials science community for surface stress measurements, is used to measure with high sensitivity the displacement of a target plate placed in a plasma thruster exhaust. The instrument has been installed inside a vacuum chamber and calibrated via two different methods and is able to measure forces in the range of 0.02-0.5 mN with a resolution of 15 {mu}N. Measurements have been made of the force produced from the cold gas flow and with a discharge ignited using argon propellant. The plasma is generated using a Helicon Double Layer Thruster prototype. The instrument target is placed about 1 mean free path for ion-neutral charge exchange collisions downstream of the thruster exit. At this position, the plasma consists of a low density ion beam (10%) and a much larger downstream component (90%). The results are in good agreement with those determined from the plasma parameters measured with diagnostic probes. Measurements at various flow rates show that variations in ion beam velocity and plasma density and the resulting momentum flux can be measured with this instrument. The instrument target is a simple, low cost device, and since the laser displacement system used is located outside the vacuum chamber, the measurement technique is free from radio frequency interference and thermal effects. It could be used to measure the thrust in the exhaust of other electric propulsion devices and the momentum flux of ion beams formed by expanding plasmas or fusion experiments.

  13. A high sensitivity momentum flux measuring instrument for plasma thruster exhausts and diffusive plasmas

    Science.gov (United States)

    West, Michael D.; Charles, Christine; Boswell, Rod W.

    2009-05-01

    A high sensitivity momentum flux measuring instrument based on a compound pendulum has been developed for use with electric propulsion devices and radio frequency driven plasmas. A laser displacement system, which builds upon techniques used by the materials science community for surface stress measurements, is used to measure with high sensitivity the displacement of a target plate placed in a plasma thruster exhaust. The instrument has been installed inside a vacuum chamber and calibrated via two different methods and is able to measure forces in the range of 0.02-0.5mN with a resolution of 15μN. Measurements have been made of the force produced from the cold gas flow and with a discharge ignited using argon propellant. The plasma is generated using a Helicon Double Layer Thruster prototype. The instrument target is placed about 1 mean free path for ion-neutral charge exchange collisions downstream of the thruster exit. At this position, the plasma consists of a low density ion beam (10%) and a much larger downstream component (90%). The results are in good agreement with those determined from the plasma parameters measured with diagnostic probes. Measurements at various flow rates show that variations in ion beam velocity and plasma density and the resulting momentum flux can be measured with this instrument. The instrument target is a simple, low cost device, and since the laser displacement system used is located outside the vacuum chamber, the measurement technique is free from radio frequency interference and thermal effects. It could be used to measure the thrust in the exhaust of other electric propulsion devices and the momentum flux of ion beams formed by expanding plasmas or fusion experiments.

  14. The importance of narcissism in predicting proactive and reactive aggression in moderately to highly aggressive children.

    Science.gov (United States)

    Barry, Tammy D; Thompson, Alice; Barry, Christopher T; Lochman, John E; Adler, Kristy; Hill, Kwoneathia

    2007-01-01

    The present study examined the importance of psychopathy-linked narcissism in predicting proactive and reactive aggression and conduct problems in a group of 160 moderately to highly aggressive children (mean age of 10 years, 9 months). Children's self-report of self-esteem and parent and teacher report of dimensions of psychopathy [narcissism, callous-unemotional (CU) traits, and impulsivity], proactive and reactive aggression, and conduct problems were collected. Composites of parent and teacher ratings of children's behavior were used. Consistent with the study's hypotheses, narcissism predicted unique variance in both proactive and reactive aggression, even when controlling for other dimensions of psychopathy, demographic variables associated with narcissism, and the alternative subtype of aggression. As hypothesized, impulsivity was significantly associated with only reactive aggression. CU traits were not related to proactive or reactive aggression once the control variables were entered. All dimensions of psychopathy predicted unique variance in conduct problems. Consistent with prediction, narcissism was not significantly related to general self-esteem, providing support that narcissism and self-esteem are different constructs. Furthermore, narcissism and self-esteem related differentially to proactive aggression, reactive aggression, and conduct problems. Furthermore, narcissism but not self-esteem accounted for unique variance in aggression and conduct problems. The importance of narcissism in the prediction of aggressive behaviors and clinical implications are discussed.

  15. Cluster observes formation of high-beta plasma blobs

    Directory of Open Access Journals (Sweden)

    G. Haerendel

    2004-07-01

    Full Text Available Late in a sequence of four moderate substorms on 26 July 2001, Cluster observed periods of a few minutes durations of high-beta plasma events (B<10nT, β=2-30, connected with dipolarizations of the magnetic field. Cluster was located near 02:45 MLT, at R=19RE and at about 5°N GSM. These events began late in the recovery phase of the second and about 5min before onset of the third substorm and lasted for three hours, way beyond the recovery phase of the fourth substorm. The most remarkable observation is that the onset coincided with the arrival of energetic (E~7keV O+ ions and energetic electrons obviously from the ionosphere, which tended to dominate the plasma composition throughout the remaining time. The magnetic flux and plasma transport is continuously directed equatorward and earthward, with oscillatory east-west movements superposed. Periods of the order of 5-10min and strong correlations between the magnetic elevation angle and log β (correlation coefficient 0.78 are highly reminiscent of the high-beta plasma blobs discovered with Equator-S and Geotail between 9 and 11RE in the late night/early morning sector (Haerendel et al., 1999.

    We conclude that Cluster observed the plasma blob formation in the tail plasma sheet, which seems to occur predominantly in the recovery and post-recovery phases of substorms. This is consistent with the finding of Equator-S and Geotail. The origin is a pulsed earthward plasma transport with velocity amplitudes of only several tens of km/s.

  16. Baseline high heat flux and plasma facing materials for fusion

    Science.gov (United States)

    Ueda, Y.; Schmid, K.; Balden, M.; Coenen, J. W.; Loewenhoff, Th.; Ito, A.; Hasegawa, A.; Hardie, C.; Porton, M.; Gilbert, M.

    2017-09-01

    In fusion reactors, surfaces of plasma facing components (PFCs) are exposed to high heat and particle flux. Tungsten and Copper alloys are primary candidates for plasma facing materials (PFMs) and coolant tube materials, respectively, mainly due to high thermal conductivity and, in the case of tungsten, its high melting point. In this paper, recent understandings and future issues on responses of tungsten and Cu alloys to fusion environments (high particle flux (including T and He), high heat flux, and high neutron doses) are reviewed. This review paper includes; Tritium retention in tungsten (K. Schmid and M. Balden), Impact of stationary and transient heat loads on tungsten (J.W. Coenen and Th. Loewenhoff), Helium effects on surface morphology of tungsten (Y. Ueda and A. Ito), Neutron radiation effects in tungsten (A. Hasegawa), and Copper and copper alloys development for high heat flux components (C. Hardie, M. Porton, and M. Gilbert).

  17. Treatment of methyl orange by nitrogen non-thermal plasma in a corona reactor: The role of reactive nitrogen species

    Energy Technology Data Exchange (ETDEWEB)

    Cadorin, Bruno Mena, E-mail: brunomenacadorin@gmail.com [Department of Chemistry, Universidade Federal de Santa Catarina (Brazil); Tralli, Vitor Douglas [Department of Chemistry, Universidade Federal de Santa Catarina (Brazil); Ceriani, Elisa [Department of Chemical Sciences, Università di Padova (Italy); Benetoli, Luís Otávio de Brito [Department of Chemistry, Universidade Federal de Santa Catarina (Brazil); Marotta, Ester, E-mail: ester.marotta@unipd.it [Department of Chemical Sciences, Università di Padova (Italy); Ceretta, Claudio [Department of Industrial Engineering, Università di Padova (Italy); Debacher, Nito Angelo [Department of Chemistry, Universidade Federal de Santa Catarina (Brazil); Paradisi, Cristina [Department of Chemical Sciences, Università di Padova (Italy)

    2015-12-30

    Highlights: • Nitration of methyl orange is one of the main processes in treatment with N{sub 2}-plasma. • MS/MS analysis shows preferred nitration of methyl orange in ortho position. • N{sub 2} plasma, N{sub 2}-PAW, reaction with NO{sub 2}{sup −} or NO{sub 2}{sup −}/H{sub 2}O{sub 2} at pH 2 give the same products. - Abstract: Methyl orange (MO) azo dye served as model organic pollutant to investigate the role of reactive nitrogen species (RNS) in non-thermal plasma (NTP) induced water treatments. The results of experiments in which MO aqueous solutions were directly exposed to N{sub 2}-NTP are compared with those of control experiments in which MO was allowed to react with nitrite, nitrate and hydrogen peroxide, which are species formed in water exposed to N{sub 2}-NTP. Treatment of MO was also performed in PAW, Plasma Activated Water, that is water previously exposed to N{sub 2}-NTP. Both direct N{sub 2}-NTP and N{sub 2}-PAW treatments induced the rapid decay of MO. No appreciable reaction was instead observed when MO was treated with NO{sub 3}{sup −} and H{sub 2}O{sub 2} either under acidic or neutral pH. In contrast, in acidic solutions MO decayed rapidly when treated with NO{sub 2}{sup −} and with a combination of NO{sub 2}{sup −} and H{sub 2}O{sub 2}. Thorough product analysis was carried out by HPLC coupled with UV–vis and ESI–MS/MS detectors. In all experiments in which MO reaction was observed, the major primary product was a derivative nitro-substituted at the ortho position with respect to the N,N-dimethylamino group of MO. The reactions of RNS are discussed and a mechanism for the observed nitration products is proposed.

  18. Characteristics of extreme ultraviolet emission from high-Z plasmas

    Science.gov (United States)

    Ohashi, H.; Higashiguchi, T.; Suzuki, Y.; Kawasaki, M.; Suzuki, C.; Tomita, K.; Nishikino, M.; Fujioka, S.; Endo, A.; Li, B.; Otsuka, T.; Dunne, P.; O'Sullivan, G.

    2016-03-01

    We demonstrate the extreme ultraviolet (EUV) and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6.x nm and the water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on high-Z plasma UTA source, coupled to multilayer mirror optics.

  19. Application of Plasma Waveguides to High Energy Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Milchberg, Howard M

    2013-03-30

    The eventual success of laser-plasma based acceleration schemes for high-energy particle physics will require the focusing and stable guiding of short intense laser pulses in reproducible plasma channels. For this goal to be realized, many scientific issues need to be addressed. These issues include an understanding of the basic physics of, and an exploration of various schemes for, plasma channel formation. In addition, the coupling of intense laser pulses to these channels and the stable propagation of pulses in the channels require study. Finally, new theoretical and computational tools need to be developed to aid in the design and analysis of experiments and future accelerators. Here we propose a 3-year renewal of our combined theoretical and experimental program on the applications of plasma waveguides to high-energy accelerators. During the past grant period we have made a number of significant advances in the science of laser-plasma based acceleration. We pioneered the development of clustered gases as a new highly efficient medium for plasma channel formation. Our contributions here include theoretical and experimental studies of the physics of cluster ionization, heating, explosion, and channel formation. We have demonstrated for the first time the generation of and guiding in a corrugated plasma waveguide. The fine structure demonstrated in these guides is only possible with cluster jet heating by lasers. The corrugated guide is a slow wave structure operable at arbitrarily high laser intensities, allowing direct laser acceleration, a process we have explored in detail with simulations. The development of these guides opens the possibility of direct laser acceleration, a true miniature analogue of the SLAC RF-based accelerator. Our theoretical studies during this period have also contributed to the further development of the simulation codes, Wake and QuickPIC, which can be used for both laser driven and beam driven plasma based acceleration schemes. We

  20. Direct evidence of reactive ion etching induced damages in Ge{sub 2}Sb{sub 2}Te{sub 5} based on different halogen plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Li, Juntao [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Microsystem Technology Laboratory, Microsystem & Terahertz Research Center, Sichuan Province 610200 (China); Xia, Yangyang [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100080 (China); Liu, Bo, E-mail: liubo@mail.sim.ac.cn [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Feng, Gaoming [United Lab, Semiconductor Manufacturing International Corporation, Shanghai 201203 (China); Song, Zhitang [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Gao, Dan; Xu, Zhen; Wang, Weiwei [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100080 (China); Chan, Yipeng [United Lab, Semiconductor Manufacturing International Corporation, Shanghai 201203 (China); Feng, Songlin [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

    2016-08-15

    Highlights: • The results of SEM and AFM directly showed that the surface of Cl2 etched samples were roughest with a Ge deficient damaged layer. • The XPS of Te 3d revealed the electrons were transferred from chalcogenide to halogen and the highest halogenation was observed on CF4 etching GST films. • The sidewall of HBr etching GST is nearly vertical compared with others. • HBr is promising gas for GST etching in the fabrication of high-density memory devices. - Abstract: Chalcogenide glasses based on Ge-Te-Sb are processed using reactive ion etching (RIE) in the fabrication of phase change memory (PCM). These materials are known to be halogenated easily and apt to be damaged when exposed to halogen gas based plasmas which can cause severe halogenation-induced degradation. In this paper, we investigate the RIE induced damage of popular phase change material Ge{sub 2}Sb{sub 2}Te{sub 5} (GST) in different halogen based plasmas (CF{sub 4}, Cl{sub 2} and HBr) highly diluted by argon. After blanket etching, results of scanning electron microscopy and atomic force microscopy directly showed that the surface of Cl{sub 2} etched samples were roughest with a Ge deficient damaged layer. X-ray photoelectron spectroscopy was performed to investigate the chemical shift of constituent elements. Selected scans over the valence band peaks of Te 3d revealed that electrons were transferred from chalcogenide to halogen and the highest halogenation was observed on the GST etched by CF{sub 4}. The GST films masked with patterned TiN were also etched. High-resolution transmission electron microscopy and surface scan directly showed the line profile and the damaged layer. Almost vertical and smooth sidewall without damaged layer makes HBr a promising gas for GST etch in the fabrication of high-density memory devices.

  1. Self-sustained focusing of high-density streaming plasma

    Science.gov (United States)

    Bugaev, A.; Dobrovolskiy, A.; Goncharov, A.; Gushenets, V.; Litovko, I.; Naiko, I.; Oks, E.

    2017-01-01

    We describe our observations of the transport through an electrostatic plasma lens of a wide-aperture, high-current, low energy, metal-ion plasma flow produced by a cathodic arc discharge. The lens input aperture was 80 mm, the length of the lens was 140 mm, and there were three electrostatic ring electrodes located in a magnetic field formed by permanent magnets. The lens outer electrodes were grounded and the central electrode was biased up to -3 kV. The plasma was a copper plasma with directed (streaming) ion energy 20-40 eV, and the equivalent ion current was up to several amperes depending on the potential applied to the central lens electrode. We find that when the central lens electrode is electrically floating, the current density of the plasma flow at the lens focus increases by up to 40%-50%, a result that is in good agreement with a theoretical treatment based on plasma-optical principles of magnetic insulation of electrons and equipotentialization along magnetic field lines. When the central lens electrode is biased negatively, an on-axis stream of energetic electrons is formed, which can also provide a mechanism for focusing of the plasma flow. Optical emission spectra under these conditions show an increase in intensity of lines corresponding to both copper atoms and singly charged copper ions, indicating the presence of fast electrons within the lens volume. These energetic electrons, as well as accumulating on-axis and providing ion focusing, can also assist in reducing the microdroplet component in the dense, low-temperature, metal plasma.

  2. Time resolved measurement of film growth during reactive high power pulsed magnetron sputtering (HIPIMS) of titanium nitride

    CERN Document Server

    Mitschker, Felix; Benedikt, Jan; Maszl, Christian; von Keudell, Achim

    2013-01-01

    The growth rate during reactive high power pulsed magnetron sputtering (HIPIMS) of titanium nitride is measured with a temporal resolution of up to 25 us using a rotating shutter concept. According to that concept a 200 um slit is rotated in front of the substrate synchronous with the HIPIMS pulses. Thereby, the growth flux is laterally distributed over the substrate. By measuring the resulting deposition profile with profilometry and with x-ray photoelectron spectroscopy, the temporal variation of the titanium and nitrogen growth flux per pulse is deduced. The analysis reveals that film growth occurs mainly during a HIPIMS pulse, with the growth rate following the HIPIMS phases ignition, current rise, gas rarefaction, plateau and afterglow. The growth fluxes of titanium and nitrogen follow slightly different behaviors with titanium dominating at the beginning of the HIPIMS pulse and nitrogen at the end of the pulse. This is explained by the gas rarefaction effect resulting in a dense initial metal plasma and...

  3. Excitation and Ionisation dynamics in high-frequency plasmas

    Science.gov (United States)

    O'Connell, D.

    2008-07-01

    Non-thermal low temperature plasmas are widely used for technological applications. Increased demands on plasma technology have resulted in the development of various discharge concepts based on different power coupling mechanisms. Despite this, power dissipation mechanisms in these discharges are not yet fully understood. Of particular interest are low pressure radio-frequency (rf) discharges. The limited understanding of these discharges is predominantly due to the complexity of the underlying mechanisms and difficult diagnostic access to important parameters. Optical measurements are a powerful diagnostic tool offering high spatial and temporal resolution. Optical emission spectroscopy (OES) provides non-intrusive access, to the physics of the plasma, with comparatively simple experimental requirements. Improved advances in technology and modern diagnostics now allow deeper insight into fundamental mechanisms. In low pressure rf discharges insight into the electron dynamics within the rf cycle can yield vital information. This requires high temporal resolution on a nano-second time scale. The optical emission from rf discharges exhibits temporal variations within the rf cycle. These variations are particularly strong, in for example capacitively coupled plasmas (CCPs), but also easily observable in inductively coupled plasmas (ICPs), and can be exploited for insight into power dissipation. Interesting kinetic and non-linear coupling effects are revealed in capacitive systems. The electron dynamics exhibits a complex spatio-temporal structure. Excitation and ionisation, and, therefore, plasma sustainment is dominated through directed energetic electrons created through the dynamics of the plasma boundary sheath. In the relatively simple case of an asymmetric capacitively coupled rf plasma the complexity of the power dissipation is exposed and various mode transitions can be clearly observed and investigated. At higher pressure secondary electrons dominate the

  4. High-density operation of the Proto-MPEX High Intensity Plasma Source

    Science.gov (United States)

    Caughman, J. B. O.; Goulding, R. H.; Biewer, T. M.; Bigelow, T. S.; Campbell, I. H.; Caneses, J.; Diem, S. J.; Martin, E. H.; Parish, C. M.; Rapp, J.; Ray, H. B.; Shaw, G. C.; Showers, M. A.; Donovan, D.; Piotrowicz, P. A.; Martin, D. C.

    2016-10-01

    The Prototype Materials Plasma Experiment (Proto-MPEX) is a linear high-intensity RF plasma source that combines a high-density helicon plasma generator with ion and electron heating sections. It is being used to study the physics of heating over-dense plasmas in a linear configuration with the goal of delivering a plasma heat flux of 10 MW/m2 at a target. The helicon plasma is produced by coupling 13.56 MHz RF power at levels of >100 kW. A 30 kW ion cyclotron antenna has recently been installed, and microwaves at 28 GHz ( 150 kW) are coupled to the electrons in the over-dense helicon plasma via Electron Bernstein Waves (EBW). High plasma densities near the target have been produced in D ( 5 x1019/m3) , and electron temperatures range from 3 to >10 eV, depending on the source parameters. IR camera images of the target plate indicate plasma heat depositions >10 MW/m2 for some operating conditions. Details of the experimental results of the operational domain with respect to Te and ne as well as results from initial plasma material interaction tests will be presented. ORNL is managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC-05-00OR22725.

  5. Increased plasma C-reactive protein level predicts rapid progression of non-target atherosclerotic lesions in patients with stable angina after stenting

    Institute of Scientific and Technical Information of China (English)

    XU Yan-lu; MA Wei-hua; YAO Min; LIU Hai-bo; WU Yong-jian; CHEN Jue; YOU Shi-jie; DAI Jun; XIA Ran; GAO Run-lin; LI Jian-jun; XU Bo; ZHUCheng-gang; YANG Yue-jin; CHEN Ji-lin; QIAO Shu-bing; YUAN Jin-qing; QIN Xue-wen

    2011-01-01

    Background Although the role of C-reactive protein (CRP) in predicting rapid progression of atherosclerotic lesions has been intensively studied in unstable coronary artery disease, the data from patients with stable angina (SA) are largely absent. The present study evaluated a middle-size patient cohort who underwent percutaneous coronary intervention (PCI) with stent implantation and follow-up coronary angiography (CAG) and tested the hypothesis that increased plasma level of high-sensitive CRP would indicate rapid progression of de novo non-target coronary artery lesions in Chinese patients with SA.Methods The study population comprised of 311 consecutive patients with chronic SA who underwent coronary stent implantation on initial admission and angiographic follow-up ((8.5±1.2) months). Rapid angiographic progression of non-target lesion was angiographically assessed and the patients were classified into two groups according to whether the progression existed or not. The relation of plasma CRP levels to the progression of atherosclerosis was investigated.Results Baseline demographic, clinical, and angiographic data were similar in patients with and without progression.Rapid angiographic progression of non-target lesions occurred in 136 patients (43.7%) at follow-up: 77 had a ≥10%diameter reduction of pre-existing stenosis ≥50%, 26 had a ≥30% diameter reduction of a pre-existing stenosis <50%, 64 developed a new lesion ≥30% in a previously normal segment, and 4 had progression of a lesion to total occlusion.Progression of non-target lesions was not associated with target lesion restenosis formation. High-sensitive CRP levels were markedly higher in progression patients than in non-progression ones (1.60 (0.80-3.46) mg/L vs. 0.96 (0.55-1.87)mg/L, P <0.001). Multivariate regression analysis showed that plasma CRP independently predicted rapid angiographic progression of non-target lesions (P=0.001). High-sensitive CRP levels above 1.32 mg

  6. Plasma-based polarization modulator for high-intensity lasers

    Science.gov (United States)

    Chen, Zi-Yu; Pukhov, Alexander

    2016-12-01

    Manipulation of laser pulses at high intensities is an important yet challenging issue. New types of plasma-based optical devices are promising alternatives to achieve this goal. Here we propose to modulate the polarization state of intense lasers based on oblique reflection from solid-plasma surfaces. A new analytical description is presented considering the plasma as an uniaxial medium that causes birefringence effect. Particle-in-cell simulation results numerically demonstrate that such a scheme can provide a tunable polarization control of the laser pulses even in the relativistic regime. The results are thus relevant for the design of compact, easy to use, and versatile polarization modulators for high-intensity laser pulses.

  7. THE HIGH TEMPERATURE CHEMICAL REACTIVITY OF LI2O

    Energy Technology Data Exchange (ETDEWEB)

    Kessinger, G.; Missimer, D.

    2009-11-13

    ) It is likely that some or all of the past high temperature phase behavior and vaporization experiments involving Li{sub 2}O(s) at temperatures above 1250 C have actually involved Li{sub 2}O(l). If these past measurements were actually measurements performed on Li{sub 2}O(l) instead of the solid, the thermochemical data for phases and species in the Li-O system will require reevaluation.

  8. SiNx Coatings Deposited by Reactive High Power Impulse Magnetron Sputtering: Process Parameters Influencing the Nitrogen Content.

    Science.gov (United States)

    Schmidt, Susann; Hänninen, Tuomas; Goyenola, Cecilia; Wissting, Jonas; Jensen, Jens; Hultman, Lars; Goebbels, Nico; Tobler, Markus; Högberg, Hans

    2016-08-10

    Reactive high power impulse magnetron sputtering (rHiPIMS) was used to deposit silicon nitride (SiNx) coatings for biomedical applications. The SiNx growth and plasma characterization were conducted in an industrial coater, using Si targets and N2 as reactive gas. The effects of different N2-to-Ar flow ratios between 0 and 0.3, pulse frequencies, target power settings, and substrate temperatures on the discharge and the N content of SiNx coatings were investigated. Plasma ion mass spectrometry shows high amounts of ionized isotopes during the initial part of the pulse for discharges with low N2-to-Ar flow ratios of <0.16, while signals from ionized molecules rise with the N2-to-Ar flow ratio at the pulse end and during pulse-off times. Langmuir probe measurements show electron temperatures of 2-3 eV for nonreactive discharges and 5.0-6.6 eV for discharges in transition mode. The SiNx coatings were characterized with respect to their composition, chemical bond structure, density, and mechanical properties by X-ray photoelectron spectroscopy, X-ray reflectivity, X-ray diffraction, and nanoindentation, respectively. The SiNx deposition processes and coating properties are mainly influenced by the N2-to-Ar flow ratio and thus by the N content in the SiNx films and to a lower extent by the HiPIMS frequencies and power settings as well as substrate temperatures. Increasing N2-to-Ar flow ratios lead to decreasing growth rates, while the N content, coating densities, residual stresses, and the hardness increase. These experimental findings were corroborated by density functional theory calculations of precursor species present during rHiPIMS.

  9. High-rate diamond deposition by microwave plasma CVD

    Science.gov (United States)

    Li, Xianglin

    In this dissertation, the growth of CVD (Chemical Vapor Deposition) diamond thin films is studied both theoretically and experimentally. The goal of this research is to deposit high quality HOD (Highly Oriented Diamond) films with a growth rate greater than 1 mum/hr. For the (100)-oriented HOD films, the growth rate achieved by the traditional process is only 0.3 mum/hr while the theoretical limit is ˜0.45 mum/hr. This research increases the growth rate up to 5.3 mum/hr (with a theoretical limit of ˜7 mum/hr) while preserving the crystal quality. This work builds a connection between the theoretical study of the CVD process and the experimental research. The study is extended from the growth of regular polycrystalline diamond to highly oriented diamond (HOD) films. For the increase of the growth rate of regular polycrystalline diamond thin films, a scaling growth model developed by Goodwin is introduced in details to assist in the understanding of the MPCVD (Microwave Plasma CVD) process. Within the Goodwin's scaling model, there are only four important sub-processes for the growth of diamond: surface modification, adsorption, desorption, and incorporation. The factors determining the diamond growth rate and film quality are discussed following the description of the experimental setup and process parameters. Growth rate and crystal quality models are reviewed to predict and understand the experimental results. It is shown that the growth rate of diamond can be increased with methane input concentration and the amount of atomic hydrogen (by changing the total pressure). It is crucial to provide enough atomic hydrogen to conserve crystal quality of the deposited diamond film. The experimental results demonstrate that for a fixed methane concentration, there is a minimum pressure for growth of good diamond. Similarly, for a fixed total pressure, there is a maximum methane concentration for growth of good diamond, and this maximum methane concentration increases

  10. A High Temperature Liquid Plasma Model of the Sun

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2007-01-01

    Full Text Available In this work, a liquid model of the Sun is presented wherein the entire solar mass is viewed as a high density/high energy plasma. This model challenges our current understanding of the densities associated with the internal layers of the Sun, advocating a relatively constant density, almost independent of radial position. The incompressible nature of liquids is advanced to prevent solar collapse from gravitational forces. The liquid plasma model of the Sun is a non-equilibrium approach, where nuclear reactions occur throughout the solar mass. The primary means of addressing internal heat transfer are convection and conduction. As a result of the convective processes on the solar surface, the liquid model brings into question the established temperature of the solar photosphere by highlighting a violation of Kirchhoff’s law of thermal emission. Along these lines, the model also emphasizes that radiative emission is a surface phenomenon. Evidence that the Sun is a high density/high energy plasma is based on our knowledge of Planckian thermal emission and condensed matter, including the existence of pressure ionization and liquid metallic hydrogen at high temperatures and pressures. Prior to introducing the liquid plasma model, the historic and scientific justifications for the gaseous model of the Sun are reviewed and the gaseous equations of state are also discussed.

  11. Counter-facing plasma focus system as a repetitive and/or long-pulse high energy density plasma source

    Science.gov (United States)

    Aoyama, Yutaka; Nakajima, Mitsuo; Horioka, Kazuhiko

    2009-11-01

    A plasma focus system composed of a pair of counter-facing coaxial plasma guns is proposed as a long-pulse and/or repetitive high energy density plasma source. A proof-of-concept experiment demonstrated that with an assist of breakdown and outer electrode connections, current sheets evolved into a configuration for stable plasma confinement at the center of the electrodes. The current sheets could successively compress and confine the high energy density plasma every half period of the discharge current, enabling highly repetitive light emissions in extreme ultraviolet region with time durations in at least ten microseconds.

  12. Low energy, high power hydrogen neutral beam for plasma heating

    Energy Technology Data Exchange (ETDEWEB)

    Deichuli, P.; Davydenko, V.; Ivanov, A., E-mail: ivanov@inp.nsk.su; Mishagin, V.; Sorokin, A.; Stupishin, N. [Budker Institute of Nuclear Physics, Prospect Lavrentieva 11, 630090 Novosibirsk (Russian Federation); Korepanov, S.; Smirnov, A. [Tri Alpha Energy, Inc., Foothill Ranch, California 92610 (United States)

    2015-11-15

    A high power, relatively low energy neutral beam injector was developed to upgrade of the neutral beam system of the gas dynamic trap device and C2-U experiment. The ion source of the injector produces a proton beam with the particle energy of 15 keV, current of up to 175 A, and pulse duration of a few milliseconds. The plasma emitter of the ion source is produced by superimposing highly ionized plasma jets from an array of four arc-discharge plasma generators. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase the efficiency and improve the uniformity of the plasma emitter. Multi-slit grids with 48% transparency are fabricated from bronze plates, which are spherically shaped to provide geometrical beam focusing. The focal length of the Ion Optical System (IOS) is 3.5 m and the initial beam diameter is 34 cm. The IOS geometry and grid potentials were optimized numerically to ensure accurate beam formation. The measured angular divergences of the beam are ±0.01 rad parallel to the slits and ±0.03 rad in the transverse direction.

  13. Low energy, high power hydrogen neutral beam for plasma heating

    Science.gov (United States)

    Deichuli, P.; Davydenko, V.; Ivanov, A.; Korepanov, S.; Mishagin, V.; Smirnov, A.; Sorokin, A.; Stupishin, N.

    2015-11-01

    A high power, relatively low energy neutral beam injector was developed to upgrade of the neutral beam system of the gas dynamic trap device and C2-U experiment. The ion source of the injector produces a proton beam with the particle energy of 15 keV, current of up to 175 A, and pulse duration of a few milliseconds. The plasma emitter of the ion source is produced by superimposing highly ionized plasma jets from an array of four arc-discharge plasma generators. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase the efficiency and improve the uniformity of the plasma emitter. Multi-slit grids with 48% transparency are fabricated from bronze plates, which are spherically shaped to provide geometrical beam focusing. The focal length of the Ion Optical System (IOS) is 3.5 m and the initial beam diameter is 34 cm. The IOS geometry and grid potentials were optimized numerically to ensure accurate beam formation. The measured angular divergences of the beam are ±0.01 rad parallel to the slits and ±0.03 rad in the transverse direction.

  14. Nanosecond-Pulsed DBD Plasma-Generated Reactive Oxygen Species Trigger Immunogenic Cell Death in A549 Lung Carcinoma Cells through Intracellular Oxidative Stress

    Science.gov (United States)

    Lin, Abraham; Truong, Billy; Patel, Sohil; Kaushik, Nagendra; Choi, Eun Ha; Fridman, Gregory; Fridman, Alexander; Miller, Vandana

    2017-01-01

    A novel application for non-thermal plasma is the induction of immunogenic cancer cell death for cancer immunotherapy. Cells undergoing immunogenic death emit danger signals which facilitate anti-tumor immune responses. Although pathways leading to immunogenic cell death are not fully understood; oxidative stress is considered to be part of the underlying mechanism. Here; we studied the interaction between dielectric barrier discharge plasma and cancer cells for oxidative stress-mediated immunogenic cell death. We assessed changes to the intracellular oxidative environment after plasma treatment and correlated it to emission of two danger signals: surface-exposed calreticulin and secreted adenosine triphosphate. Plasma-generated reactive oxygen and charged species were recognized as the major effectors of immunogenic cell death. Chemical attenuators of intracellular reactive oxygen species successfully abrogated oxidative stress following plasma treatment and modulated the emission of surface-exposed calreticulin. Secreted danger signals from cells undergoing immunogenic death enhanced the anti-tumor activity of macrophages. This study demonstrated that plasma triggers immunogenic cell death through oxidative stress pathways and highlights its potential development for cancer immunotherapy. PMID:28467380

  15. Magnetized plasma flow injection into tokamak and high-beta compact torus plasmas

    Science.gov (United States)

    Matsunaga, Hiroyuki; Komoriya, Yuuki; Tazawa, Hiroyasu; Asai, Tomohiko; Takahashi, Tsutomu; Steinhauer, Loren; Itagaki, Hirotomo; Onchi, Takumi; Hirose, Akira

    2010-11-01

    As an application of a magnetized coaxial plasma gun (MCPG), magnetic helicity injection via injection of a highly elongated compact torus (magnetized plasma flow: MPF) has been conducted on both tokamak and field-reversed configuration (FRC) plasmas. The injected plasmoid has significant amounts of helicity and particle contents and has been proposed as a fueling and a current drive method for various torus systems. In the FRC, MPF is expected to generate partially spherical tokamak like FRC equilibrium by injecting a significant amount of magnetic helicity. As a circumstantial evidence of the modified equilibrium, suppressed rotational instability with toroidal mode number n = 2. MPF injection experiments have also been applied to the STOR-M tokamak as a start-up and current drive method. Differences in the responses of targets especially relation with beta value and the self-organization feature will be studied.

  16. An ionization region model of the reactive Ar/O2 high power impulse magnetron sputtering discharge

    Science.gov (United States)

    Gudmundsson, J. T.; Lundin, D.; Brenning, N.; Raadu, M. A.; Huo, Chunqing; Minea, T. M.

    2016-12-01

    A new reactive ionization region model (R-IRM) is developed to describe the reactive Ar/O2 high power impulse magnetron sputtering (HiPIMS) discharge with a titanium target. It is then applied to study the temporal behavior of the discharge plasma parameters such as electron density, the neutral and ion composition, the ionization fraction of the sputtered vapor, the oxygen dissociation fraction, and the composition of the discharge current. We study and compare the discharge properties when the discharge is operated in the two well established operating modes, the metal mode and the poisoned mode. Experimentally, it is found that in the metal mode the discharge current waveform displays a typical non-reactive evolution, while in the poisoned mode the discharge current waveform becomes distinctly triangular and the current increases significantly. Using the R-IRM we explore the current increase and find that when the discharge is operated in the metal mode Ar+ and Ti+ -ions contribute most significantly (roughly equal amounts) to the discharge current while in the poisoned mode the Ar+ -ions contribute most significantly to the discharge current and the contribution of O+ -ions, Ti+ -ions, and secondary electron emission is much smaller. Furthermore, we find that recycling of atoms coming from the target, that are subsequently ionized, is required for the current generation in both modes of operation. From the R-IRM results it is found that in the metal mode self-sputter recycling dominates and in the poisoned mode working gas recycling dominates. We also show that working gas recycling can lead to very high discharge currents but never to a runaway. It is concluded that the dominating type of recycling determines the discharge current waveform.

  17. High-performance modeling of plasma-based acceleration and laser-plasma interactions

    Science.gov (United States)

    Vay, Jean-Luc; Blaclard, Guillaume; Godfrey, Brendan; Kirchen, Manuel; Lee, Patrick; Lehe, Remi; Lobet, Mathieu; Vincenti, Henri

    2016-10-01

    Large-scale numerical simulations are essential to the design of plasma-based accelerators and laser-plasma interations for ultra-high intensity (UHI) physics. The electromagnetic Particle-In-Cell (PIC) approach is the method of choice for self-consistent simulations, as it is based on first principles, and captures all kinetic effects, and also scale favorably to many cores on supercomputers. The standard PIC algorithm relies on second-order finite-difference discretization of the Maxwell and Newton-Lorentz equations. We present here novel formulations, based on very high-order pseudo-spectral Maxwell solvers, which enable near-total elimination of the numerical Cherenkov instability and increased accuracy over the standard PIC method for standard laboratory frame and Lorentz boosted frame simulations. We also present the latest implementations in the PIC modules Warp-PICSAR and FBPIC on the Intel Xeon Phi and GPU architectures. Examples of applications will be given on the simulation of laser-plasma accelerators and high-harmonic generation with plasma mirrors. Work supported by US-DOE Contracts DE-AC02-05CH11231 and by the European Commission through the Marie Slowdoska-Curie fellowship PICSSAR Grant Number 624543. Used resources of NERSC.

  18. Oral Administration of the Japanese Traditional Medicine Keishibukuryogan-ka-yokuinin Decreases Reactive Oxygen Metabolites in Rat Plasma: Identification of Chemical Constituents Contributing to Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Yosuke Matsubara

    2017-02-01

    Full Text Available Insufficient detoxification and/or overproduction of reactive oxygen species (ROS induce cellular and tissue damage, and generated reactive oxygen metabolites become exacerbating factors of dermatitis. Keishibukuryogan-ka-yokuinin (KBGY is a traditional Japanese medicine prescribed to treat dermatitis such as acne vulgaris. Our aim was to verify the antioxidant properties of KBGY, and identify its active constituents by blood pharmacokinetic techniques. Chemical constituents were quantified in extracts of KBGY, crude components, and the plasma of rats treated with a single oral administration of KBGY. Twenty-three KBGY compounds were detected in plasma, including gallic acid, prunasin, paeoniflorin, and azelaic acid, which have been reported to be effective for inflammation. KBGY decreased level of the diacron-reactive oxygen metabolites (d-ROMs in plasma. ROS-scavenging and lipid hydroperoxide (LPO generation assays revealed that gallic acid, 3-O-methylgallic acid, (+-catechin, and lariciresinol possess strong antioxidant activities. Gallic acid was active at a similar concentration to the maximum plasma concentration, therefore, our findings indicate that gallic acid is an important active constituent contributing to the antioxidant effects of KBGY. KBGY and its active constituents may improve redox imbalances induced by oxidative stress as an optional treatment for skin diseases.

  19. Application of nonlinear dynamic techniques to high pressure plasma jets

    Science.gov (United States)

    Ghorui, S.; Das, A. K.

    2010-02-01

    Arcs and arc plasmas have been known and used for welding, cutting, chemical synthesis and multitude of other industrial applications for more than hundred years. Though a copious source of heat, light and active species, plasma arc is inherently unstable, turbulent and difficult to control. During recent years, primarily driven by the need of new and energy efficient materials processing, various research groups around the world have been studying new and innovative ways of looking at the issues related to arc dynamics, arc stabilization, species non equilibrium, flow and heat transfer in a stabilized arc plasma device. In this context, experimental determination of nature of arc instabilities using tools of non-linear dynamics, theoretical model formulation, prediction of instability behavior under given operating conditions and possible control methods for the observed instabilities in arcs are reviewed. Space selective probing of the zones inside arc plasma devices without disturbing the system is probably the best way to identify the originating zone of instabilities inside such devices. Existence of extremely high temperature and inaccessibility to direct experimentations due to mechanical obstructions make this task extremely difficult. Probing instabilities in otherwise inaccessible inner regions of the torches, using binary gas mixture as plasma gas is a novel technique that primarily rests on a process known as demixing in arcs. Once a binary gas mixture enters the constricted plasma column, the demixing process sets in causing spatial variations for each of the constituent gases depending on the diffusion coefficients and the gradient of the existing temperature field. By varying concentrations of the constituent gases in the feeding line, it is possible to obtain spatial variations of the plasma composition in a desired manner, enabling spatial probing of the associated zones. Detailed compositional description of different zones inside the torch may be

  20. A HIGH REPETITION PLASMA MIRROR FOR STAGED ELECTRON ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    Sokollik, Thomas; Shiraishi, Satomi; Osterhoff, Jens; Evans, Eugene; Gonsalves, Anthony; Nakamura, Kei; vanTilborg, Jeroen; Lin, Chen; Toth, Csaba; Leemans, Wim

    2011-07-22

    In order to build a compact, staged laser plasma accelerator the in-coupling of the laser beam to the different stages represents one of the key issues. To limit the spatial foot print and thus to realize a high overall acceleration gradient, a concept has to be found which realizes this in-coupling within a few centimeters. We present experiments on a tape-drive based plasma mirror which could be used to reflect the focused laser beam into the acceleration stage.

  1. Plasma backflow phenomenon in high-current vacuum arc

    Energy Technology Data Exchange (ETDEWEB)

    Wang Lijun [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Jia Shenli [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang Ling [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Shi Zongqian [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Yang Dingge [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Gentils, Francois [Schneider Electric SAS, 37 quai Paul-Louis Merlin, 38050 Grenoble Cedex 9 (France); Jusselin, BenoIt [Schneider Electric SAS, 37 quai Paul-Louis Merlin, 38050 Grenoble Cedex 9 (France)

    2007-10-07

    Based on the two-temperature magnetohydrodynamic model, a high-current vacuum arc (HCVA) in vacuum interrupters is simulated and analysed. The phenomenon of plasma backflow in arc column is found, which is ultimately ascribed to the strong magnetic pinch effect of HCVA. Due to plasma backflow, the maximal value of ion density at the cathode side is not located at the centre of the cathode side, but at the paraxial region of the cathode side, that is to say, ion density appears to sag at the centre of the cathode side (arc column seems to be divided into two parts). The sag of light intensity is also found by experiments.

  2. 14th High-Tech Plasma Processes Conference (HTPP 14)

    Science.gov (United States)

    2017-04-01

    Preface The High-Tech Plasma Processes Conference (HTPP) is a bi-annual international conference based in Europe with topics encompassing the whole area of plasma processing science. This conference is open to all the international community in the world involved in plasma science and plasma technology. The aim of the conference is to bring different scientific communities together, facilitate the contacts between science, technology and industry and provide a platform for the exploration of both fundamental topics and new applications of plasmas. For this edition of HTPP, as was the case for the last, we have achieved a well balanced participation from the communities of both thermal and non-thermal plasma researchers. 75 people from 17 countries attended the conference with the total number of contributions being 74, consisting of 19 invited talks and 55 poster contributions. As a HTPP tradition a poster competition has been carried out during the conference. The winner of the poster competition was Fabrice Mavier from Université de Limoges, France with his paper “Pulsed arc plasma jet synchronized with drop-on-demand dispenser” All the participants also ejoyed the social program including an “unconventional” tour of the city, the visit to the famous Hofbräuhaus and the dinner at the Blutenburg, a beautiful inner-city castle. We have received papers corresponding to the contributions of HTPP-2014 that have been submitted for publication in this volume of Journal of Physics: Conference Series. Each submitted contribution has been peer reviewed and the Editors are very grateful to the referees for their careful support in improving the original manuscripts. In total, 18 manuscripts have been accepted for publication covering a range of topics of plasma processing science from plasma fundamentals to process applications through to experiments, diagnostics and modelling. We deeply thank the authors for their enthusiastic and high-grade contributions and we

  3. Prognostic value of high sensitive C-reactive protein in subjects with silent myocardial ischemia

    DEFF Research Database (Denmark)

    Mouridsen, Mette; Intzilakis, Theodoros; Binici, Zeynep

    2012-01-01

    OBJECTIVES: The aim of this study was to evaluate the prognostic value of high sensitive C-reactive protein (CRP) in subjects with silent myocardial ischemia (SMI). DESIGN: In total, 678 healthy men and women aged 55 to 75 years with no history of cardiovascular disease or stroke were included...

  4. High-sensitive C-reactive protein is associated with reduced lung function in young adults

    DEFF Research Database (Denmark)

    Rasmussen, F; Mikkelsen, D; Hancox, R J;

    2009-01-01

    Systemic inflammation has been associated with reduced lung function. However, data on the interrelationships between lung function and inflammation are sparse, and it is not clear if low-grade inflammation leads to reduced lung function. Associations between high-sensitive C-reactive protein (CR...

  5. Responses of Solid Tumor Cells in DMEM to Reactive Oxygen Species Generated by Non-Thermal Plasma and Chemically Induced ROS Systems

    Science.gov (United States)

    Kaushik, Neha; Uddin, Nizam; Sim, Geon Bo; Hong, Young June; Baik, Ku Youn; Kim, Chung Hyeok; Lee, Su Jae; Kaushik, Nagendra Kumar; Choi, Eun Ha

    2015-02-01

    In this study, we assessed the role of different reactive oxygen species (ROS) generated by soft jet plasma and chemical-induced ROS systems with regard to cell death in T98G, A549, HEK293 and MRC5 cell lines. For a comparison with plasma, we generated superoxide anion (O2-), hydroxyl radical (HO.), and hydrogen peroxide (H2O2) with chemicals inside an in vitro cell culture. Our data revealed that plasma decreased the viability and intracellular ATP values of cells and increased the apoptotic population via a caspase activation mechanism. Plasma altered the mitochondrial membrane potential and eventually up-regulated the mRNA expression levels of BAX, BAK1 and H2AX gene but simultaneously down-regulated the levels of Bcl-2 in solid tumor cells. Moreover, a western blot analysis confirmed that plasma also altered phosphorylated ERK1/2/MAPK protein levels. At the same time, using ROS scavengers with plasma, we observed that scavengers of HO. (mannitol) and H2O2 (catalase and sodium pyruvate) attenuated the activity of plasma on cells to a large extent. In contrast, radicals generated by specific chemical systems enhanced cell death drastically in cancer as well as normal cell lines in a dose-dependent fashion but not specific with regard to the cell type as compared to plasma.

  6. Charged Particle Motion in a Highly Ionized Plasma

    CERN Document Server

    Brown, L S; Singleton, R; Brown, Lowell S; Preston, Dean L; Singleton, Robert L

    2005-01-01

    A recently introduced method utilizing dimensional continuation is employed to compute the energy loss rate for a non-relativistic particle moving through a highly ionized plasma. No restriction is made on the charge, mass, or speed of this particle. It is, however, assumed that the plasma is not strongly coupled in the sense that the dimensionless plasma coupling parameter g=e^2\\kappa_D/ 4\\pi T is small, where \\kappa_D is the Debye wave number of the plasma. To leading and next-to-leading order in this coupling, dE/dx is of the generic form g^2 \\ln[C g^2]. The precise numerical coefficient out in front of the logarithm is well known. We compute the constant C under the logarithm exactly for arbitrary particle speeds. Our exact results differ from approximations given in the literature. The differences are in the range of 20% for cases relevant to inertial confinement fusion experiments. The same method is also employed to compute the rate of momentum loss for a projectile moving in a plasma, and the rate at ...

  7. Transport studies in high-performance field reversed configuration plasmas

    Science.gov (United States)

    Gupta, S.; Barnes, D. C.; Dettrick, S. A.; Trask, E.; Tuszewski, M.; Deng, B. H.; Gota, H.; Gupta, D.; Hubbard, K.; Korepanov, S.; Thompson, M. C.; Zhai, K.; Tajima, T.

    2016-05-01

    A significant improvement of field reversed configuration (FRC) lifetime and plasma confinement times in the C-2 plasma, called High Performance FRC regime, has been observed with neutral beam injection (NBI), improved edge stability, and better wall conditioning [Binderbauer et al., Phys. Plasmas 22, 056110 (2015)]. A Quasi-1D (Q1D) fluid transport code has been developed and employed to carry out transport analysis of such C-2 plasma conditions. The Q1D code is coupled to a Monte-Carlo code to incorporate the effect of fast ions, due to NBI, on the background FRC plasma. Numerically, the Q1D transport behavior with enhanced transport coefficients (but with otherwise classical parametric dependencies) such as 5 times classical resistive diffusion, classical thermal ion conductivity, 20 times classical electron thermal conductivity, and classical fast ion behavior fit with the experimentally measured time evolution of the excluded flux radius, line-integrated density, and electron/ion temperature. The numerical study shows near sustainment of poloidal flux for nearly 1 ms in the presence of NBI.

  8. Highly Multiplexed Profiling of Low Abundance Tumor Mutations in Plasma

    Science.gov (United States)

    Wiggin, Matthew; Pel, Joel; Vysotskaia, Valentina; Broemeling, David; Marziali, Andre; Hanson, Dan

    2013-01-01

    We have demonstrated a novel somatic mutation enrichment methodology demonstrating multiplexed detection of tumor mutations in plasma with sensitivity as low as 0.01% compared to normal DNA. This highly sensitive detection of low abundance mutations is achieved using electrophoretic separation and enrichment of DNA fragments containing point mutations over their wild-type counterparts. Commercialized as the OnTarget platform by Boreal Genomics, the system enriches nucleic acid samples for specific targets prior to amplification and detection, enabling the use of next-generation sequencing (NGS) or other detection assays for plasma or FFPE-based mutation detection and profiling. We present data demonstrating highly sensitive and multiplexed detection of panels of up to 100 mutations in plasma samples, improving the sensitivity of NGS assays to below 0.01% mutant content. We also report on concordance studies comparing low tumor content FFPE tissue and matched plasma in human samples demonstrating that OnTarget represents a robust, highly sensitive and multiplexed platform for non-invasive tumor monitoring.

  9. Genetic variation in estrogen receptor, C-reactive protein and fibrinogen does not predict the plasma levels of inflammation markers after longterm hormone replacement therapy

    DEFF Research Database (Denmark)

    de Maat, Moniek P M; Madsen, Jonna Skov; Langdahl, Bente Lomholt;

    2007-01-01

    Markers of inflammation, such as C-reactive protein (CRP) and fibrinogen, are associated with the risk of atherothrombosis. Plasma levels of these markers of inflammation are affected by hormone replacement therapy (HRT) and modulated by smoking. We studied whether genetic variation in the estrogen...... receptor- 1 (ESR1), CRP and fibrinogen-beta genes influences the plasma levels of inflammation markers after HRT. Plasma CRP and fibrinogen were measured after five years follow-up in healthy postmenopausal women (per-protocol group) who were randomised to hormone therapy (n=187) or no treatment (n=249......). The effect of HRT, smoking and genetic variations in ESR1 (PvuII and XbaI), CRP (1444C/T) and fibrinogen-beta (FGB, -455G/A) were determined. The plasma concentration of CRP was higher in the HRT group than in the control group (2.03 mg/l and 1.41 mg/l, respectively; p

  10. The chemical and mechanical behaviors of polymer / reactive metal systems under high strain rates

    Science.gov (United States)

    Shen, Yubin

    As one category of energetic materials, impact-initiated reactive materials are able to release a high amount of stored chemical energy under high strain rate impact loading, and are used extensively in civil and military applications. In general, polymers are introduced as binder materials to trap the reactive metal powders inside, and also act as an oxidizing agent for the metal ingredient. Since critical attention has been paid on the metal / metal reaction, only a few types of polymer / reactive metal interactions have been studied in the literature. With the higher requirement of materials resistant to different thermal and mechanical environments, the understanding and characterization of polymer / reactive metal interactions are in great demand. In this study, PTFE (Polytetrafluoroethylene) 7A / Ti (Titanium) composites were studied under high strain rates by utilizing the Taylor impact and SHPB tests. Taylor impact tests with different impact velocities, sample dimensions and sample configurations were conducted on the composite, equipped with a high-speed camera for tracking transient images during the sudden process. SHPB and Instron tests were carried out to obtain the stress vs. strain curves of the composite under a wide range of strain rates, the result of which were also utilized for fitting the constitutive relations of the composite based on the modified Johnson-Cook strength model. Thermal analyses by DTA tests under different flow rates accompanied with XRD identification were conducted to study the reaction mechanism between PTFE 7A and Ti when only heat was provided. Numerical simulations on Taylor impact tests and microstructural deformations were also performed to validate the constitutive model built for the composite system, and to investigate the possible reaction mechanism between two components. The results obtained from the high strain rate tests, thermal analyses and numerical simulations were combined to provide a systematic study on

  11. Spectroscopy Measurements on Ablation Testing in High Enthalpy Plasma Flows

    Science.gov (United States)

    2010-11-01

    stagnation point, are located on the ablative material sample. 3.5 InfraRed THERMOGRAPHY Surface temperature measurement is a topic of great concern...high temperature material at two different narrow wavelengths. The temperature is calculated by building the ratio of the radiation intensities. The...this work is to develop the capability of testing and characterization of ablative materials exposed to high enthalpy plasma flows including both

  12. Space and Astrophysical Plasmas : High energy universe – Satellite missions

    Indian Academy of Sciences (India)

    Vinod Krishan

    2000-11-01

    A variety of satellite missions to observe the high energy universe are currently operating and some more with more versatility and capability are on the anvil. In this paper, after giving a brief introduction to the constituents of the high energy universe and the related plasma physical problems, general as well as specific features of the current and future x-ray and gamma-ray satellite missions are described.

  13. Effects of Low Energy and High Flux Helium/Hydrogen Plasma Irradiation on Tungsten as Plasma Facing Material

    Institute of Scientific and Technical Information of China (English)

    Ye Minyou

    2005-01-01

    The High-Z material tungsten (W) has been considered as a plasma facing material in the divertor region of ITER (International Thermonuclear Experimental Reactor). In ITER, the divertor is expected to operate under high particle fluxes (> 1023 m-2s-1) from the plasma as well as from intrinsic impurities with a very low energy (< 200 eV). During the past dacade, the effects of plasma irradiation on tungsten have been studied extensively as functions of the ion energy,fluence and surface temperature in the burning plasma conditions. In this paper, recent results concerning blister and bubble formations on the tungsten surface under low energy (< 100 eV) and high flux (> 1021 m-2s-1) He/H plasma irradiation are reviewed to gain a better understanding of the performance of tungsten as a plasma facing material under the burning plasma conditions.

  14. Stoichiometric silicon oxynitride thin films reactively sputtered in Ar/N2O plasmas by HiPIMS

    Science.gov (United States)

    Hänninen, Tuomas; Schmidt, Susann; Wissting, Jonas; Jensen, Jens; Hultman, Lars; Högberg, Hans

    2016-04-01

    Silicon oxynitride (SiO x N y , x=0.2-1.3, y=0.2 -0.7) thin films were synthesized by reactive high power impulse magnetron sputtering from a pure silicon target in Ar/N2O atmospheres. It was found that the composition of the material can be controlled by the reactive gas flow and the average target power. X-ray photoelectron spectroscopy (XPS) shows that high average powers result in more silicon-rich films, while lower target powers yield silicon-oxide-like material due to more pronounced target poisoning. The amount of nitrogen in the films can be controlled by the percentage of nitrous oxide in the working gas. The nitrogen content remains at a constant level while the target is operated in the transition region between metallic and poisoned target surface conditions. The extent of target poisoning is gauged by the changes in peak target current under the different deposition conditions. XPS also shows that varying concentrations and ratios of oxygen and nitrogen in the films result in film chemical bonding structures ranging from silicon-rich to stoichiometric silicon oxynitrides having no observable Si-Si bond contributions. Spectroscopic ellipsometry shows that the film optical properties depend on the amount and ratio of oxygen and nitrogen in the compound, with film refractive indices measured at 633 nm ranging between those of SiO2 and Si3N4.

  15. Enhanced selection of high affinity DNA-reactive B cells following cyclophosphamide treatment in mice.

    Directory of Open Access Journals (Sweden)

    Daisuke Kawabata

    Full Text Available A major goal for the treatment of patients with systemic lupus erythematosus with cytotoxic therapies is the induction of long-term remission. There is, however, a paucity of information concerning the effects of these therapies on the reconstituting B cell repertoire. Since there is recent evidence suggesting that B cell lymphopenia might attenuate negative selection of autoreactive B cells, we elected to investigate the effects of cyclophosphamide on the selection of the re-emerging B cell repertoire in wild type mice and transgenic mice that express the H chain of an anti-DNA antibody. The reconstituting B cell repertoire in wild type mice contained an increased frequency of DNA-reactive B cells; in heavy chain transgenic mice, the reconstituting repertoire was characterized by an increased frequency of mature, high affinity DNA-reactive B cells and the mice expressed increased levels of serum anti-DNA antibodies. This coincided with a significant increase in serum levels of BAFF. Treatment of transgene-expressing mice with a BAFF blocking agent or with DNase to reduce exposure to autoantigen limited the expansion of high affinity DNA-reactive B cells during B cell reconstitution. These studies suggest that during B cell reconstitution, not only is negative selection of high affinity DNA-reactive B cells impaired by increased BAFF, but also that B cells escaping negative selection are positively selected by autoantigen. There are significant implications for therapy.

  16. A high-fat meal increases cardiovascular reactivity to psychological stress in healthy young adults.

    Science.gov (United States)

    Jakulj, Fabijana; Zernicke, Kristin; Bacon, Simon L; van Wielingen, Laura E; Key, Brenda L; West, Sheila G; Campbell, Tavis S

    2007-04-01

    The consumption of high levels of saturated fat over the course of several weeks may lead to exaggerated cardiovascular reactivity. The consumption of a single high-fat meal has been associated with a transient impairment of vascular function. In a randomized, repeated measures, crossover study we tested whether the consumption of a single high-fat meal by healthy, normotensive participants would affect cardiovascular reactivity when compared with an isocaloric, low-fat meal. Thirty healthy participants ate a high-fat (42 g) and a low-fat (1 g) meal on 2 separate occasions, and their cardiovascular response to 2 standard laboratory stressors was measured. Systolic blood pressure, diastolic blood pressure, and total peripheral resistance were greater in participants following the consumption of the high-fat meal relative to the low-fat meal. The findings of the present study are consistent with the hypothesis that even a single high-fat meal may be associated with heightened cardiovascular reactivity to stress and offer insight into the pathways through which a high-fat diet may affect cardiovascular function.

  17. High Power Light Gas Helicon Plasma Source For VASMIR

    Science.gov (United States)

    Squire, J. P.; Chang-Diaz, F. R.; Glover, T. W.; Jacobson, V. T.; McCaskill, G. E.; Winter, D. S.; Baity, F. W.; Carter, M. D.; Goulding, R. H.

    2004-01-01

    The VASIMR space propulsion development effort relies on a high power (greater than 10kW) helicon source to produce a dense flowing plasma (H, D and He) target for ion cyclotron resonance (ICR) acceleration of the ions. Subsequent expansion in an expanding magnetic field (magnetic nozzle) converts ion lunetic energy to directed momentum. This plasma source must have critical features to enable an effective propulsion device. First, it must ionize most of the input neutral flux of gas, thus producing a plasma stream with a high degree of ionization for application of ICR power. This avoids propellant waste and potential power losses due to charge exchange. Next, the plasma stream must flow into a region of high magnetic field (approximately 0.5 T) for efficient ICR acceleration. Third, the ratio of input power to plasma flux must be low, providing an energy per ion-electron pair approaching 100 eV. Lastly, the source must be robust and capable of very long life-times (years). In our helicon experiment (VX-10) we have measured a ratio of input gas to plasma flux near 100%. The plasma flows from the helicon region (B approximately 0.1 T) into a region with a peak magnetic field of 0.8 T. The energy input per ion-electron pair has been measured at 300 plus or minus 100 eV. Recent results at Oak Ridge National Laboratory (ORNL) show an enhanced efficiency mode of operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 3.5 kW of input power. An upgrade to a power level of 10 kW is underway. Much of our recent work has been with a Boswell double-saddle antenna design. We are also converting the antenna design to a helical type. With these modifications, we anticipate an improvement in the ionization efficiency. This paper presents the results from scaling the helicon in the VX-10 device from 3.5 to 10 kW. We also compare the operation with a double-saddle to a helical antenna design. Finally, we

  18. High Power Light Gas Helicon Plasma Source For VASMIR

    Science.gov (United States)

    Squire, J. P.; Chang-Diaz, F. R.; Glover, T. W.; Jacobson, V. T.; McCaskill, G. E.; Winter, D. S.; Baity, F. W.; Carter, M. D.; Goulding, R. H.

    2004-01-01

    The VASIMR space propulsion development effort relies on a high power (greater than 10kW) helicon source to produce a dense flowing plasma (H, D and He) target for ion cyclotron resonance (ICR) acceleration of the ions. Subsequent expansion in an expanding magnetic field (magnetic nozzle) converts ion lunetic energy to directed momentum. This plasma source must have critical features to enable an effective propulsion device. First, it must ionize most of the input neutral flux of gas, thus producing a plasma stream with a high degree of ionization for application of ICR power. This avoids propellant waste and potential power losses due to charge exchange. Next, the plasma stream must flow into a region of high magnetic field (approximately 0.5 T) for efficient ICR acceleration. Third, the ratio of input power to plasma flux must be low, providing an energy per ion-electron pair approaching 100 eV. Lastly, the source must be robust and capable of very long life-times (years). In our helicon experiment (VX-10) we have measured a ratio of input gas to plasma flux near 100%. The plasma flows from the helicon region (B approximately 0.1 T) into a region with a peak magnetic field of 0.8 T. The energy input per ion-electron pair has been measured at 300 plus or minus 100 eV. Recent results at Oak Ridge National Laboratory (ORNL) show an enhanced efficiency mode of operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 3.5 kW of input power. An upgrade to a power level of 10 kW is underway. Much of our recent work has been with a Boswell double-saddle antenna design. We are also converting the antenna design to a helical type. With these modifications, we anticipate an improvement in the ionization efficiency. This paper presents the results from scaling the helicon in the VX-10 device from 3.5 to 10 kW. We also compare the operation with a double-saddle to a helical antenna design. Finally, we

  19. Plasma relaxation mechanics of pulsed high power microwave surface flashover

    Energy Technology Data Exchange (ETDEWEB)

    Beeson, S.; Dickens, J.; Neuber, A. [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States)

    2013-09-15

    Microwave transmission and reflection characteristics of pulsed radio frequency field generated plasmas are elucidated for air, N{sub 2}, and He environments under pressure conditions ranging from 10 to 600 torr. The pulsed, low temperature plasma is generated along the atmospheric side of the dielectric boundary between the source (under vacuum) and the radiating environment with a thickness on the order of 5 mm and a cross sectional area just smaller than that of the waveguide. Utilizing custom multi-standard waveguide couplers and a continuous low power probing source, the scattering parameters were measured before, during, and after the high power microwave pulse with emphasis on the latter. From these scattering parameters, temporal electron density estimations (specifically the longitudinal integral of the density) were calculated using a 1D plane wave-excited model for analysis of the relaxation processes associated. These relaxation characteristics ultimately determine the maximum repetition rate for many pulsed electric field applications and thus are applicable to a much larger scope in the plasma community than just those related to high power microwaves. This manuscript discusses the diagnostic setup for acquiring the power measurements along with a detailed description of the kinematic and chemical behavior of the plasma as it decays down to its undisturbed state under various gas type and pressure conditions.

  20. High-frequency underwater plasma discharge application in antibacterial activity

    Science.gov (United States)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U.; Mongre, R. K.; Jeong, D. K.; Suresh, R.; Lee, H. J.

    2017-03-01

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli ( E. coli) by generating high-frequency, high-voltage, oxygen (O2) injected and hydrogen peroxide (H2O2) added discharge in water was achieved. The effect of H2O2 dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H2O2 addition with O2 injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH•, H, and O). Interestingly, the results demonstrated that O2 injected and H2O2 added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  1. High-frequency underwater plasma discharge application in antibacterial activity

    Science.gov (United States)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U.; Mongre, R. K.; Jeong, D. K.; Suresh, R.; Lee, H. J.

    2017-03-01

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli (E. coli) by generating high-frequency, high-voltage, oxygen (O2) injected and hydrogen peroxide (H2O2) added discharge in water was achieved. The effect of H2O2 dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H2O2 addition with O2 injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH•, H, and O). Interestingly, the results demonstrated that O2 injected and H2O2 added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  2. High-frequency underwater plasma discharge application in antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U. [Jeju National University, Department of Nuclear and Energy Engineering (Korea, Republic of); Mongre, R. K.; Jeong, D. K. [Jeju National University, Faculty of Biotechnology (Korea, Republic of); Suresh, R.; Lee, H. J., E-mail: hjlee@jejunu.ac.kr [Jeju National University, Department of Nuclear and Energy Engineering (Korea, Republic of)

    2017-03-15

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli (E. coli) by generating high-frequency, high-voltage, oxygen (O{sub 2}) injected and hydrogen peroxide (H{sub 2}O{sub 2}) added discharge in water was achieved. The effect of H{sub 2}O{sub 2} dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H{sub 2}O{sub 2} addition with O{sub 2} injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH{sup •}, H, and O). Interestingly, the results demonstrated that O{sub 2} injected and H{sub 2}O{sub 2} added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  3. Alpha reactivity to first names differs in subjects with high and low dream recall frequency

    OpenAIRE

    Perrine Marie RUBY; Camille eBlochet; Jean-Baptiste eEichenlaub; Olivier eBertrand; Dominique eMorlet; Aurélie eBidet-Caulet

    2013-01-01

    Studies in cognitive psychology showed that personality (openness to experience, thin boundaries, absorption), creativity, nocturnal awakenings, and attitude toward dreams are significantly related to dream recall frequency (DRF). These results suggest the possibility of neurophysiological trait differences between subjects with high and low DRF. To test this hypothesis we compared sleep characteristics and alpha reactivity to sounds in subjects with high and low DRF using polysomnographic re...

  4. Helicon waves in uniform plasmas. II. High m numbers

    Energy Technology Data Exchange (ETDEWEB)

    Stenzel, R. L.; Urrutia, J. M. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)

    2015-09-15

    Helicons are whistler modes with azimuthal wave numbers. They have been studied in solids and plasmas where boundaries play a role. The present work shows that very similar modes exist in unbounded gaseous plasmas. Instead of boundaries, the antenna properties determine the topology of the wave packets. The simplest antenna is a magnetic loop which excites m = 0 or m = 1 helicons depending on whether the dipole moment is aligned parallel or perpendicular to the ambient background magnetic field B{sub 0}. While these low order helicons have been described by J. M. Urrutia and R. L. Stenzel [“Helicon modes in uniform plasmas. I. Low m modes,” Phys. Plasmas 22, 092111 (2015)], the present work focuses on high order modes up to m = 8. These are excited by antenna arrays forming magnetic multipoles. Their wave magnetic field has been measured in space and time in a large and uniform laboratory plasma free of boundary effects. The observed wave topology exhibits m pairs of unique field line spirals which may have inspired the name “helicon” to this mode. All field lines converge into these nested spirals which propagate like corkscrews along B{sub 0}. The field lines near the axis of helicons are perpendicular to B{sub 0} and circularly polarized as in parallel whistlers. Helical antennas couple to these transverse fields but not to the spiral fields of helicons. Using a circular antenna array of phased m = 0 loops, right or left rotating or non-rotating multipole antenna fields are generated. They excite m < 0 and m > 0 modes, showing that the plasma supports both modes equally well. The poor excitation of m < 0 modes is a characteristic of loops with dipole moment across B{sub 0}. The radiation efficiency of multipole antennas has been found to decrease with m.

  5. Antidepressant treatment differentially affects the phenotype of high and low stress reactive mice.

    Science.gov (United States)

    Surget, Alexandre; Van Nieuwenhuijzen, Petra S; Heinzmann, Jan-Michael; Knapman, Alana; McIlwrick, Silja; Westphal, Willy-Paul; Touma, Chadi; Belzung, Catherine

    2016-11-01

    Modelling key endophenotypes can be a powerful approach to gain insight into mechanisms underlying the aetiology and pathophysiology of neuropsychiatric disorders. Based on evidence of stress hormone system dysregulations in depression, the Stress Reactivity (SR) mouse model has been generated by a selective breeding approach for extremes in HPA axis reactivity, resulting in high (HR), intermediate (IR) and low (LR) reactive mice. The characterisation of their phenotypic alterations has highlighted many similarities of HR and LR mice with the melancholic and atypical depression, respectively. We therefore aimed to examine whether the antidepressant fluoxetine (10 mg/kg/day i.p., 4-5 weeks) can ameliorate the phenotypic characteristics of HR and LR mice in neuroendocrine functions (HPA axis basal activity, stress reactivity, negative feedback), emotional reactivity/coping-strategy (open field, forced swim tests), spatial learning/memory (Morris water-maze) and hippocampal neurogenesis. Line differences in HPA axis reactivity were maintained under fluoxetine treatment. However, we observed fluoxetine effects on glucocorticoid-induced negative feedback, stress-coping behaviours, cognitive functions and neurogenesis. Specifically, our results revealed line-dependent consequences of fluoxetine treatment: (1) an amelioration of the 'melancholic-like' features of HR mice (reversing the negative feedback resistance, the hyperactive coping style and the memory deficits; increasing hippocampal neurogenesis); (2) an exacerbation of the phenotypic deviations of LR mice (increasing their pronounced negative feedback and passive coping style). Thus, these findings support the predictive validity of antidepressant treatment in the HR mouse line and emphasize the translational value of the SR mouse model for the development of therapeutic strategies based on endophenotype-driven classifications.

  6. Preparation of inhalable salbutamol sulphate using reactive high gravity controlled precipitation.

    Science.gov (United States)

    Hu, Tingting; Chiou, Herbert; Chan, Hak-Kim; Chen, Jian-Feng; Yun, Jimmy

    2008-02-01

    Reactive high gravity controlled precipitation (HGCP) was carried out to produce salbutamol sulphate (SS) particles suitable for inhalation. Aqueous solutions of free salbutamol base and sulphuric acid were mixed intensely inside a HGCP reactor to form the particles. Spray drying was employed to obtain dry powders. Physical properties of the powders were characterised by scanning electron microscopy, X-ray powder diffraction, thermal gravimetric analysis and dynamic water vapour sorption. Aerosol performance of the powders was measured using an Aeroliser connected to a multiple stage liquid impinger operating at 60 L/min. The results showed that the reactive HGCP powder, comprising primary SS sub-micron particles (approximately 100 nm in width and approximately 500 nm in length) packed into loose spherical agglomerates of about 2 microm in diameter, is of the same polymorphic form as the raw crystalline material, has a high specific surface area (24.7 +/- 0.1 m(2)/g), but a low moisture content (0.2%) and low moisture uptake (1.4% at RH 90%). The aerosol performance of the reactive HGCP powder is excellent, showing FPF(loaded) and FPF(emitted) of 76 +/- 5% and 83 +/- 7%, respectively, with low capsule and device retention. In conclusion, reactive HGCP followed by spray drying is suitable to produce stable crystalline powders of salbutamol with enhanced inhalation properties.

  7. Amino-terminated biphenylthiol self-assembled monolayers as highly reactive molecular templates

    Energy Technology Data Exchange (ETDEWEB)

    Meyerbroeker, N.; Waske, P.; Zharnikov, M., E-mail: Michael.Zharnikov@urz.uni-heidelberg.de

    2015-03-14

    Self-assembled monolayers (SAMs) with amino tail groups are of interest due to their ability of coupling further compounds. Such groups can be, in particular, created by electron irradiation of nitro- or nitrile-substituted aromatic SAMs, which provide a basis for chemical nanolithography and the fabrication of functionalized nanomembranes. An estimate of reactivity of the created amino groups requires a reference system of homogeneous, amino-terminated aromatic SAMs, which can also be used as a highly reactive molecular template. Here, we describe the synthesis of 4′-aminobiphenyl-4-thiol (ABPT) and SAMs prepared from this precursor on Au(111). The monolayers were characterized by X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure spectroscopy, which revealed that they are well defined, chemically uniform, densely packed, and highly ordered. To examine the influence of electron irradiation on the reactivity of the terminal amino groups, ABPT SAMs were exposed to low energy (50 eV) electrons up to a dose of 40 mC/cm{sup 2} and, subsequently, immersed in either trifluoroacetic, pentafluoropropionic, or heptafluorobutyric anhydride. Analysing the amount of the attached anhydride species made it possible to determine the percentage of reactive amino groups as well as the effect of steric hindrance upon the coupling reaction. The above results are compared with those obtained for the well-established nitro-substituted biphenylthiol monolayers.

  8. Amino-terminated biphenylthiol self-assembled monolayers as highly reactive molecular templates.

    Science.gov (United States)

    Meyerbroeker, N; Waske, P; Zharnikov, M

    2015-03-14

    Self-assembled monolayers (SAMs) with amino tail groups are of interest due to their ability of coupling further compounds. Such groups can be, in particular, created by electron irradiation of nitro- or nitrile-substituted aromatic SAMs, which provide a basis for chemical nanolithography and the fabrication of functionalized nanomembranes. An estimate of reactivity of the created amino groups requires a reference system of homogeneous, amino-terminated aromatic SAMs, which can also be used as a highly reactive molecular template. Here, we describe the synthesis of 4'-aminobiphenyl-4-thiol (ABPT) and SAMs prepared from this precursor on Au(111). The monolayers were characterized by X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure spectroscopy, which revealed that they are well defined, chemically uniform, densely packed, and highly ordered. To examine the influence of electron irradiation on the reactivity of the terminal amino groups, ABPT SAMs were exposed to low energy (50 eV) electrons up to a dose of 40 mC/cm(2) and, subsequently, immersed in either trifluoroacetic, pentafluoropropionic, or heptafluorobutyric anhydride. Analysing the amount of the attached anhydride species made it possible to determine the percentage of reactive amino groups as well as the effect of steric hindrance upon the coupling reaction. The above results are compared with those obtained for the well-established nitro-substituted biphenylthiol monolayers.

  9. A manganese catalyst for highly reactive yet chemoselective intramolecular C(sp3)-H amination

    Science.gov (United States)

    Paradine, Shauna M.; Griffin, Jennifer R.; Zhao, Jinpeng; Petronico, Aaron L.; Miller, Shannon M.; Christina White, M.

    2015-12-01

    C-H bond oxidation reactions underscore the existing paradigm wherein high reactivity and high selectivity are inversely correlated. The development of catalysts capable of oxidizing strong aliphatic C(sp3)-H bonds while displaying chemoselectivity (that is, tolerance of more oxidizable functionality) remains an unsolved problem. Here, we describe a catalyst, manganese tert-butylphthalocyanine [Mn(tBuPc)], that is an outlier to the reactivity-selectivity paradigm. It is unique in its capacity to functionalize all types of C(sp3)-H bond intramolecularly, while displaying excellent chemoselectivity in the presence of π functionality. Mechanistic studies indicate that [Mn(tBuPc)] transfers bound nitrenes to C(sp3)-H bonds via a pathway that lies between concerted C-H insertion, observed with reactive noble metals such as rhodium, and stepwise radical C-H abstraction/rebound, as observed with chemoselective base metals such as iron. Rather than achieving a blending of effects, [Mn(tBuPc)] aminates even 1° aliphatic and propargylic C-H bonds, demonstrating reactivity and selectivity unusual for previously known catalysts.

  10. A manganese catalyst for highly reactive yet chemoselective intramolecular C(sp(3))-H amination.

    Science.gov (United States)

    Paradine, Shauna M; Griffin, Jennifer R; Zhao, Jinpeng; Petronico, Aaron L; Miller, Shannon M; Christina White, M

    2015-12-01

    C-H bond oxidation reactions underscore the existing paradigm wherein high reactivity and high selectivity are inversely correlated. The development of catalysts capable of oxidizing strong aliphatic C(sp(3))-H bonds while displaying chemoselectivity (that is, tolerance of more oxidizable functionality) remains an unsolved problem. Here, we describe a catalyst, manganese tert-butylphthalocyanine [Mn((t)BuPc)], that is an outlier to the reactivity-selectivity paradigm. It is unique in its capacity to functionalize all types of C(sp(3))-H bond intramolecularly, while displaying excellent chemoselectivity in the presence of π functionality. Mechanistic studies indicate that [Mn((t)BuPc)] transfers bound nitrenes to C(sp(3))-H bonds via a pathway that lies between concerted C-H insertion, observed with reactive noble metals such as rhodium, and stepwise radical C-H abstraction/rebound, as observed with chemoselective base metals such as iron. Rather than achieving a blending of effects, [Mn((t)BuPc)] aminates even 1° aliphatic and propargylic C-H bonds, demonstrating reactivity and selectivity unusual for previously known catalysts.

  11. High-Density Plasma Reactors: Simulations for Design

    Science.gov (United States)

    Hash, David B.; Meyyappan, Meyya; Arnold, James O. (Technical Monitor)

    1998-01-01

    The development of improved and more efficient plasma reactors is a costly process for the semiconductor industry. Until five years ago, the Industry made most of its advancements through a trial and error approach. More recently, the role of computational modeling in the design process has increased. Both conventional computational fluid dynamics (CFD) techniques like Navier-Stokes solvers as well as particle simulation methods are used to model plasma reactor flowfields. However, since high-density plasma reactors generally operate at low gas pressures on the order of 1 to 10 mTorr, a particle simulation may be necessary because of the failure of CFD techniques to model rarefaction effects. The direct simulation Monte Carlo method is the most widely accepted and employed particle simulation tool and has previously been used to investigate plasma reactor flowfields. A plasma DSMC code is currently under development at NASA Ames Research Center with its foundation as the object-oriented parallel Cornell DSMC code, MONACO. The present investigation is a follow up of a neutral flow investigation of the effects of process parameters as well as reactor design on etch rate and etch rate uniformity. The previous work concentrated on silicon etch of a chlorine flow in a configuration typical of electron cyclotron resonance (ECR) or helical resonator type reactors. The effects of the plasma on the dissociation chemistry were modeled by making assumptions about the electron temperature and number density. The electrons or ions themselves were not simulated.The present work extends these results by simulating the charged species.The electromagnetic fields are calculated such that power deposition is modeled self-consistently. Electron impact reactions are modeled along with mechanisms for charge exchange. An bipolar diffusion assumption is made whereby electrons remain tied to the ions. However, the velocities of tile electrons are allowed to be modified during collisions

  12. Synthesising highly reactive tin oxide using Tin(II2- ethylhexanoate polynucleation as precursor

    Directory of Open Access Journals (Sweden)

    Alejandra Montenegro Hernández

    2010-05-01

    Full Text Available Tin oxide is a widely used compound in technological applications, particularity as a catalyst, gas sensor and in making varistors, transparent conductors, electrocatalytic electrodes and photovoltaic cells. An ethylhexanoate tin salt, a carboxylic acid and poly-esterification were used for synthesising highly reactive tin oxide in the present study. Synthesis was controlled by Fourier transform infrared (FTIR spectroscopy and recording changes in viscosity. The tin oxide characteristics so obtained were determined using FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The SnO2 dust synthesised and heat-treated at 550°C yielded high density aggregates, having greater than 50 μm particle size. This result demonstrates the high reactivity of the ceramic powders synthesised here.

  13. The correlation between high sensitivity C-Reactive Protein level and the Extent of Coronary Lesion and Cardiac Systolic Function in Coronary Heart Disease

    Directory of Open Access Journals (Sweden)

    Miftah Suryadipradja

    2003-12-01

    Full Text Available To determine the mean value of high sensitivity C-Reactive Protein (hs-CRP, association between plasma level of hs-CRP with extent of disease and systolic function. A cross sectional study had been conducted to 106 coronary artery disease patients (90 stable angina pectoris, 11 unstable angina pectoris and 5 acute myocardial infarction. Plasma quantitative level of hs-CRP with cor angiography to determine extent of disease and ejection fraction were measured. The mean of hs-CRP levels in patients with SVD were 5,5 ± 7,6 mg/L, DVD were 6,6 ± 21,7 mg/L and TVD were 5,5 ± 8,0 mg/L and p=0,056, respectively. There were no significant association between hs- CRP levels with extent of disease. Systolic function had negative correlation with levels of hs-CRP (p=0,015, r=-0,235. This study showed that plasma level of hs-CRP cannot reflect the extent of disease, and it had negative correlation with systolic function. (Med J Indones 2003; 12: 201-6 Keywords: high sensitivity C-Reactive Protein, extent of disease, systolic function, coronary artery diseases.

  14. Simulation of transition dynamics to high confinement in fusion plasmas

    DEFF Research Database (Denmark)

    Nielsen, Anders Henry; Xu, G. S.; Madsen, Jens;

    2015-01-01

    The transition dynamics from the low (L) to the high (H) confinement mode in magnetically confined plasmas is investigated using a first-principles four-field fluid model. Numerical results are in agreement with measurements from the Experimental Advanced Superconducting Tokamak - EAST. Particula......The transition dynamics from the low (L) to the high (H) confinement mode in magnetically confined plasmas is investigated using a first-principles four-field fluid model. Numerical results are in agreement with measurements from the Experimental Advanced Superconducting Tokamak - EAST....... Particularly, the slow transition with an intermediate dithering phase is well reproduced at proper parameters. The model recovers the power threshold for the L-H transition as well as the decrease in power threshold switching from single to double null configuration observed experimentally. The results...

  15. High power microwave source for a plasma wakefield experiment

    Science.gov (United States)

    Shafir, G.; Shlapakovski, A.; Siman-Tov, M.; Bliokh, Yu.; Leopold, J. G.; Gleizer, S.; Gad, R.; Rostov, V. V.; Krasik, Ya. E.

    2017-01-01

    The results of the generation of a high-power microwave (˜550 MW, 0.5 ns, ˜9.6 GHz) beam and feasibility of wakefield-excitation with this beam in under-dense plasma are presented. The microwave beam is generated by a backward wave oscillator (BWO) operating in the superradiance regime. The BWO is driven by a high-current electron beam (˜250 keV, ˜1.5 kA, ˜5 ns) propagating through a slow-wave structure in a guiding magnetic field of 2.5 T. The microwave beam is focused at the desired location by a dielectric lens. Experimentally obtained parameters of the microwave beam at its waist are used for numerical simulations, the results of which demonstrate the formation of a bubble in the plasma that has almost 100% electron density modulation and longitudinal and transverse electric fields of several kV/cm.

  16. A new study on the penetration of reactive species in their mass transfer processes in water by increasing the electron energy in plasmas

    Science.gov (United States)

    Jiang, Jixiang; Tan, Zhenyu; Shan, Chunhong; Pan, Jie; Pan, Guangsheng; Liu, Yadi; Chen, Xinxian; Wang, Xiaolong

    2016-10-01

    In this work, the mass transfer of the reactive species from the plasmas in the water layer has been investigated by means of the numerical simulation based on the one-dimensional drift-diffusion model. The depth distributions of five main reactive species, OH, O3, HO2, O2-, and H2O2, have been presented, when considering the dissociative electron attachment (DEA) to the water molecule by increasing electron energy in the plasmas. The present work shows that the DEA to the water molecule plays an important role in the penetration of the species OH, O3, and HO2. With the increase in electron energy, HO2 quenches after the penetration depth of a few micrometers, becoming a short-living species, but the penetration depths of O3 and OH increase evidently, up to a few tens micrometers, which is of significance for the application of cold atmospheric-pressure plasmas in biomedical engineering. In addition, the contribution of each dominative reaction to production or loss of OH has also been calculated and analyzed under the different electron energies because of the importance of OH in the inactivation of biomolecules and in order to have a good knowledge of the mechanisms of OH production as well as its penetration in the water layer. The present work is a first effort toward the goal of increasing the different types of the reactive species that may interact with cellular components after the mass transfer of the plasmas in the water layer, by changing the discharge parameters of the plasmas.

  17. High expression of CD26 accurately identifies human bacteria-reactive MR1-restricted MAIT cells.

    Science.gov (United States)

    Sharma, Prabhat K; Wong, Emily B; Napier, Ruth J; Bishai, William R; Ndung'u, Thumbi; Kasprowicz, Victoria O; Lewinsohn, Deborah A; Lewinsohn, David M; Gold, Marielle C

    2015-07-01

    Mucosa-associated invariant T (MAIT) cells express the semi-invariant T-cell receptor TRAV1-2 and detect a range of bacteria and fungi through the MHC-like molecule MR1. However, knowledge of the function and phenotype of bacteria-reactive MR1-restricted TRAV1-2(+) MAIT cells from human blood is limited. We broadly characterized the function of MR1-restricted MAIT cells in response to bacteria-infected targets and defined a phenotypic panel to identify these cells in the circulation. We demonstrated that bacteria-reactive MR1-restricted T cells shared effector functions of cytolytic effector CD8(+) T cells. By analysing an extensive panel of phenotypic markers, we determined that CD26 and CD161 were most strongly associated with these T cells. Using FACS to sort phenotypically defined CD8(+) subsets we demonstrated that high expression of CD26 on CD8(+)  TRAV1-2(+) cells identified with high specificity and sensitivity, bacteria-reactive MR1-restricted T cells from human blood. CD161(hi) was also specific for but lacked sensitivity in identifying all bacteria-reactive MR1-restricted T cells, some of which were CD161(dim) . Using cell surface expression of CD8, TRAV1-2, and CD26(hi) in the absence of stimulation we confirm that bacteria-reactive T cells are lacking in the blood of individuals with active tuberculosis and are restored in the blood of individuals undergoing treatment for tuberculosis.

  18. Blistering on tungsten surface exposed to high flux deuterium plasma

    NARCIS (Netherlands)

    Xu, H.Y.; Liu, W.; Luo, G. N.; Yuan, Y.; Jia, Y. Z.; Fu, B. Q.; De Temmerman, G.

    2016-01-01

    The blistering behaviour of tungsten surfaces exposed to very high fluxes (1–2 × 1024/m2/s) of low energy (38 eV) deuterium plasmas was investigated as a function of ion fluence (0.2–7 × 1026 D/m2) and surface temperature (423–873 K). Blisters were observed under all conditions, especially up to

  19. High Performance Plasma Channel Insulators for High Power Hall Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA missions for planetary exploration require high power, long-life Hall thrusters. However, thruster power and lifetime are limited by the erosion of plasma...

  20. High Performance Plasma Channel Insulators for High Power Hall Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA missions for planetary exploration require high power, long-life Hall thrusters. However, thruster power and lifetime are limited by the erosion of plasma...

  1. Moving Overlapping Grids with Adaptive Mesh Refinement for High-Speed Reactive and Non-reactive Flow

    Energy Technology Data Exchange (ETDEWEB)

    Henshaw, W D; Schwendeman, D W

    2005-08-30

    We consider the solution of the reactive and non-reactive Euler equations on two-dimensional domains that evolve in time. The domains are discretized using moving overlapping grids. In a typical grid construction, boundary-fitted grids are used to represent moving boundaries, and these grids overlap with stationary background Cartesian grids. Block-structured adaptive mesh refinement (AMR) is used to resolve fine-scale features in the flow such as shocks and detonations. Refinement grids are added to base-level grids according to an estimate of the error, and these refinement grids move with their corresponding base-level grids. The numerical approximation of the governing equations takes place in the parameter space of each component grid which is defined by a mapping from (fixed) parameter space to (moving) physical space. The mapped equations are solved numerically using a second-order extension of Godunov's method. The stiff source term in the reactive case is handled using a Runge-Kutta error-control scheme. We consider cases when the boundaries move according to a prescribed function of time and when the boundaries of embedded bodies move according to the surface stress exerted by the fluid. In the latter case, the Newton-Euler equations describe the motion of the center of mass of the each body and the rotation about it, and these equations are integrated numerically using a second-order predictor-corrector scheme. Numerical boundary conditions at slip walls are described, and numerical results are presented for both reactive and non-reactive flows in order to demonstrate the use and accuracy of the numerical approach.

  2. Maternal plasma levels of interleukin-6, C-reactive protein, vitamins C, E and A, 8-isoprostane and oxidative status in women with preterm premature rupture of membranes.

    Science.gov (United States)

    Ilhan, Nevin; Celik, Ebru; Kumbak, Banu

    2015-02-01

    Preterm premature rupture of membranes (PPROM) is associated with significant maternal and perinatal morbidity. This study examined maternal oxidative stress in PPROM. This was a prospective cross-sectional study conducted in a university hospital. A total of 72 pregnant women were recruited into two groups, those with PPROM (38 cases) and those without PPROM (34 controls) matched for gestational age. Plasma interleukin-6, C-reactive protein, vitamins C, E and A, 8-isoprostane, total oxidant status (TOS) and antioxidant status (TAS) were determined for all study participants and the data were compared between the PPROM and control groups. Both case and control groups were comparably matched in age, parity, gestational age and smoking status. There was a significant association between low 8-isoprostane, low vitamin C and high total oxidant status and the occurrence of PPROM (p vitamin C and 8-isoprostane levels were lower and TOS higher in women with PPROM. Further research is needed to identify robust biological markers for the prevention and also prognosis of PPROM.

  3. SOME ASPECTS OF THE REACTIVITY OF PULP INTENDED FOR HIGH-VISCOSITY VISCOSE

    Directory of Open Access Journals (Sweden)

    Linda Ostberg,

    2012-01-01

    Full Text Available The motivation for this study was to reduce the consumption of C2S when preparing high-viscosity viscose by pre-treating two softwood pulps with enzymes prior to the viscose stages. Reactivity was evaluated in two ways, Fock´s test of the pulp and the gamma number of the viscose solution prior to regeneration. Whilst the reactivity of a pulp that had been subjected to enzyme pretreatment increased according to Fock´s test, it did not increase according to the gamma number. This unexpected difference between the two reactivity tests was investigated. It was concluded that Fock´s test measures the extent to which C2S reacts with a pulp sample during a standardized test, whereas the gamma number measures the resulting degree of xanthate substitution on the cellulose backbone. The gamma number was judged to be the more relevant of the two tests, since it reflects the dissolution ability of a pulp in the viscose preparation. A higher gamma number also means that the coagulation time in the spinning process is prolonged; this is beneficial, as it can be used to increase the tenacity of the viscose fibres. Measuring the reactivity according to Fock´s test, on the contrary, provides more dubious results, as the test has no undisputed correlation to the viscose preparation process.

  4. High levels of vitamin D in relation to reduced risk of schizophrenia with elevated C-reactive protein.

    Science.gov (United States)

    Zhu, Dao-min; Liu, Yong; Zhang, Ai-guo; Chu, Zhao-xue; Wu, Qing; Li, Hui; Ge, Jin-fang; Dong, Yi; Zhu, Peng

    2015-08-30

    There is growing evidence on the novel role of vitamin D in reducing inflammation. This study aimed to examine the hypothesis that vitamin D is inversely associated with C-reactive protein (CRP) in patients with schizophrenia, and high levels of vitamin D may be linked to reduced risk of schizophrenia with elevated CRP. Ninety-three patients with schizophrenia and 93 family-matched controls were recruited in this cross-sectional study. Plasma concentrations of CRP and 25-hydroxyvitamin D [25(OH)D] were measured using commercial kits. Information about demographic characteristics and clinic data were obtained by interviews or medical records. Mean levels of CRP and 25(OH)D were 43.3% higher and 26.7% lower for patients compared to controls, respectively. 25(OH)D were inversely associated with CRP in the patients, but not in the controls. The proportions of patients significantly increased with increasing quartiles of CRP, while significantly decreased with increasing quartiles of 25(OH)D. Among individuals with high CRP, participants with high 25(OH)D have significantly lower proportion (adjusted OR =0.217, 95% CI 0.063, 0.751) of schizophrenia compared to those with low 25(OH)D. The evidence suggested that high levels of vitamin D may be linked to reduced risk of schizophrenia with elevated CRP. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. 糖耐量异常对急性脑梗死患者血浆Hcy和血清hs-CRP水平的影响%The Influence of Abnormal Glucose Tolerance on the Levels of Plasma Homocysteine and Serum High-sensitivity C-reactive Protein in Patients with Acute Cerebral Infarction(ACI)

    Institute of Scientific and Technical Information of China (English)

    赵红东; 陆敏; 唐冰

    2012-01-01

    Objective To observe the influence of abnormal glucose tolerance on the levels of homocysteine and high-sensitivity C-reactive protein in patients with acute cerebral infarction( AGI). Methods 756 patients with AGI were divided into normal glucose tolerance group (NGT, 33 leases) , abnormal glucose tolerance group(IGT,142cases) ,and diabetes mellitus group (DM,283 scase) ac-cording to the result of oral glucose tolerance test( OGTT). The serum levels of Hcy and hs-GRP were measured in 24 hours after ad-mission. Result The both levels of Hey and hs-GRP in IGT group(19.17 9.35juno]/L,20.46 10.56μmol/L) and DM group (8.0 2.9 mg/L,7.7 2.3 mg/L) were higher than the NGT group with no difference between each other. Conclusion The levels of Hey and hs-GRP in patients with AGI and abnormal glucose tolerance rise significantly,which indicate the presence of chronic low-grade inflammation and atherosclerosis in the stage of abnormal glucose tolerance. The results showed abnormal glucose tolerance is the risk factor of atherosclerosis as diabetes mellitus,and the OGTT test is valuable in screening risk factors of AGI and stroke prevention.%目的:观察糖耐量异常对急性脑梗死(acute cerebral infarction,ACI)患者的同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)水平的影响.方法:756例ACI患者按葡萄糖耐量试验(OGTT)结果分为糖耐量正常组(NGT,331例)、单纯性糖耐量异常组(IGT,142例)、2型糖尿病组(DM2,283例).在入院24h之内测定血清Hcy、hs-CRP水平并进行组间比较.结果:IGT组及DM2组的Hcy水平(19.17±9.35)μmol/L、(20.46±10.56)μmol/L以及hs-CRP水平(8.0±2.9)mg/L、(7.7±2.3)mg/L明显高于NGT组(16.17±7.35)μmol/L、(3.5±1.2)mg/L.IGT组及DM2组两组之间的Hcy、hs-CRP水平差异均无统计学意义(P>0.05、P>0.05).结论:单纯性糖耐量异常的ACI患者血清Hcy、hs-CRP水平明显升高,表明在糖耐量异常阶段,已经出现了慢性低水平炎症和动脉粥样硬化的发生.提

  6. C-H bond activation by metal-superoxo species: what drives high reactivity?

    Science.gov (United States)

    Ansari, Azaj; Jayapal, Prabha; Rajaraman, Gopalan

    2015-01-01

    Metal-superoxo species are ubiquitous in metalloenzymes and bioinorganic chemistry and are known for their high reactivity and their ability to activate inert C-H bonds. The comparative oxidative abilities of M-O2(.-) species (M = Cr(III), Mn(III), Fe(III), and Cu(II)) towards C-H bond activation reaction are presented. These superoxo species generated by oxygen activation are found to be aggressive oxidants compared to their high-valent metal-oxo counterparts generated by O⋅⋅⋅O bond cleavage. Our calculations illustrate the superior oxidative abilities of Fe(III)- and Mn(III)-superoxo species compared to the others and suggest that the reactivity may be correlated to the magnetic exchange parameter.

  7. Transient Formation and Reactivity of a High-Valent Nickel(IV) Oxido Complex

    NARCIS (Netherlands)

    Padamati, Sandeep K.; Angelone, Davide; Draksharapu, Apparao; Primi, Gloria; Martin, David J.; Tromp, Moniek; Swart, Marcel; Browne, Wesley R.

    2017-01-01

    A reactive high-valent dinuclear nickel(IV) oxido bridged complex is reported that can be formed at room temperature by reaction of [(L)2Ni(II)2(μ-X)3]X (X = Cl or Br) with NaOCl in methanol or acetonitrile (where L = 1,4,7-trimethyl-1,4,7-triazacyclononane). The unusual Ni(IV) oxido species is

  8. Controlling Microbial Safety Challenges of Meat Using High Voltage Atmospheric Cold Plasma.

    Science.gov (United States)

    Han, Lu; Ziuzina, Dana; Heslin, Caitlin; Boehm, Daniela; Patange, Apurva; Sango, David M; Valdramidis, Vasilis P; Cullen, Patrick J; Bourke, Paula

    2016-01-01

    Atmospheric cold plasma (ACP) is a non-thermal technology, effective against a wide range of pathogenic microorganisms. Inactivation efficacy results from plasma generated reactive species. These may interact with any organic components in a test matrix including the target microorganism, thus food components may exert a protective effect against the antimicrobial mode of action. The effect of an in-package high voltage ACP process applied in conjunction with common meat processing MAP gas compositions as well as bacteria type and meat model media composition have been investigated to determine the applicability of this technology for decontamination of safety challenges associated with meat products. E. coli, L. monocytogenes, and S. aureus in PBS were undetectable after 60 s of treatment at 80 kVRMS in air, while ACP treatment of the contaminated meat model required post-treatment refrigeration to retain antimicrobial effect. The nutritive components in the meat model exerted a protective effect during treatment, where 300 s ACP exposure yielded a maximum reduction of 1.5 log using a high oxygen atmosphere, whilst using air and high nitrogen atmospheres yielded lower antimicrobial efficacy. Furthermore, an ROS assay was performed to understand the protective effects observed using the meat model. This revealed that nutritive components inhibited penetration of ROS into bacterial cells. This knowledge can assist the optimization of meat decontamination using ACP technology where interactions with all components of the food matrix require evaluation.

  9. Optimization of time on CF{sub 4}/O{sub 2} etchant for inductive couple plasma reactive ion etching of TiO{sub 2} thin film

    Energy Technology Data Exchange (ETDEWEB)

    Adzhri, R., E-mail: adzhri@gmail.com; Fathil, M. F. M.; Ruslinda, A. R.; Gopinath, Subash C. B.; Voon, C. H.; Foo, K. L.; Nuzaihan, M. N. M.; Azman, A. H.; Zaki, M. [Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Perlis (Malaysia); Arshad, M. K. Md., E-mail: mohd.khairuddin@unimap.edu.my; Hashim, U.; Ayub, R. M. [Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Perlis (Malaysia); School of Microelectronic Engineering, Universiti Malaysia Perlis (UniMAP), Perlis (Malaysia)

    2016-07-06

    In this work, we investigate the optimum etching of titanium dioxide (TiO{sub 2}) using inductive couple plasma reactive ion etching (ICP-RIE) on our fabricated devices. By using a combination of CF{sub 4}/O{sub 2} gases as plasma etchant with ratio of 3:1, three samples of TiO{sub 2} thin film were etched with different time duration of 10 s, 15 s and 20 s. The ion bombardment of CF{sub 4} gases with plasma enhancement by O{sub 2} gas able to break the oxide bond of TiO{sub 2} and allow anisotropic etch profile with maximum etch rate of 18.6 nm/s. The sample was characterized by using optical profilometer to determine the depth of etched area and scanning electron microscopy (SEM) for etch profile characterization.

  10. Chromium(VI)—induces Production of Reactive Oxygen Species,Change of Plasma Membrane Potential and Dissipation of Mitochondria Membrane otential in Chinese Hamster Lung Cell Cultures

    Institute of Scientific and Technical Information of China (English)

    XIEYI; ZHUANGZHI-XIONG

    2001-01-01

    Objective:To examine whether Reactive Oxygen Species(ROS) is generated,and whether plasma membrane potential and mitochnodrial membrane potential are depolarized in Chinese Hamster Lung(CHL)cell lines exposed to Cr(VI),Methods:CHL Cells were incubated with Cr(VI) at 10 umol/L,2.5umol/L,0.65umol/L for 3 and 6 hours,respectively.The rpoduction of ROS was performed by using 2,7-dichlorofluorescin discetate;The changes in plasma membrane potential were performed by using 2,7-dichlorofluorescin discetate;The changes in plasma membrane potential were performed by using 2,7-dichlorofluorescin diacetate;The changes in plasma membrane potential were estimated using fluorescent cationic dye DiBAC4;And the changes in mitochondria membrane potential were estimated using fluorescent dye Rhodamine 123,Results:The ROS levels in CHL cells increased in all treated groups compared with the control group(P<0.01);The plasma membrane potential and mitochondrial membrane potential in CHL cells dissipated after incubated with Cr(VI) at 10umol/L for 3 hours and 6 hours(P<0.01),at 2.5umol/L for 6 hours(P<0.01 or 0.05),Conclusion:Cr(VI) causes the dissipation of plasma membrane potential and mitochnodrial membrane otential in CHL cell cultrues,and Cr(VI)-induced ROS may play a role in the injuries.

  11. Three plasma metabolite signatures for diagnosing high altitude pulmonary edema

    Science.gov (United States)

    Guo, Li; Tan, Guangguo; Liu, Ping; Li, Huijie; Tang, Lulu; Huang, Lan; Ren, Qian

    2015-10-01

    High-altitude pulmonary edema (HAPE) is a potentially fatal condition, occurring at altitudes greater than 3,000 m and affecting rapidly ascending, non-acclimatized healthy individuals. However, the lack of biomarkers for this disease still constitutes a bottleneck in the clinical diagnosis. Here, ultra-high performance liquid chromatography coupled with Q-TOF mass spectrometry was applied to study plasma metabolite profiling from 57 HAPE and 57 control subjects. 14 differential plasma metabolites responsible for the discrimination between the two groups from discovery set (35 HAPE subjects and 35 healthy controls) were identified. Furthermore, 3 of the 14 metabolites (C8-ceramide, sphingosine and glutamine) were selected as candidate diagnostic biomarkers for HAPE using metabolic pathway impact analysis. The feasibility of using the combination of these three biomarkers for HAPE was evaluated, where the area under the receiver operating characteristic curve (AUC) was 0.981 and 0.942 in the discovery set and the validation set (22 HAPE subjects and 22 healthy controls), respectively. Taken together, these results suggested that this composite plasma metabolite signature may be used in HAPE diagnosis, especially after further investigation and verification with larger samples.

  12. EPOCH code simulation of a non-thermal distribution driven by neutral beam injection in a high-beta plasma

    Science.gov (United States)

    Necas, A.; Tajima, T.; Nicks, S.; Magee, R.; Clary, R.; Roche, T.; Tri Alpha Energy Team

    2016-10-01

    In Tri Alpha Energy's C-2U experiment, advanced beam-driven field-reversed configuration (FRC) plasmas were sustained via tangential neutral beam injection. The dominant fast ion population made a dramatic impact on the overall plasma performance. To explain an experimentally observed anomalous neutron signal (100x thermonuclear), we use EPOCH PIC code to simulate possible beam driven non-destructive instabilities that transfer energy from fast ions to the plasma, causing phase space bunching. We propose that the hydrogen beam ion population drives collective modes in the deuterium target plasma, giving rise to the instability and increased fusion rate. The instability changes character from electrostatic in the low beta edge to fully electromagnetic in the core, with an associated reduction in growth rates. The DD reactivity enhancement is calculated using a two-body correlation function and compared to the experimentally observed neutron yield. The high-energy tails in the distributions of the plasma deuterons and beam protons are observed via a mass-resolving Neutral Particle Analyzer (NPA) diagnostic. This observation is qualitatively consistent with EPOCH simulation of the beam-plasma instability.

  13. Electrostatic Instabilities at High Frequency in a Plasma Shock Front

    Institute of Scientific and Technical Information of China (English)

    LV Jian-Hong; HE Yong; HU Xi-Wei

    2007-01-01

    New electrostatic instabilities in the plasma shock front are reported.These instabilities are driven by the electrostatic field which is caused by charge separation and the parameter gradients in a plasma shock front.The linear analysis to the high frequency branch of electrostatic instabilities has been carried out and the dispersion relations are obtained numerically.There are unstable disturbing waves in both the parallel and perpendicular directions of shock propagation.The real frequencies of both unstable waves are similar to the electron electrostatic wave,and the unstable growth rate in the parallel direction is much greater than the one in the perpendicular direction.The dependence of growth rates on the electric field and parameter gradients is also presented.

  14. Stability and energy confinement of highly elongated plasmas in TCV

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, F.; Behn, R.; Dutch, M.J.; Martin, Y.; Moret, J.M.; Nieswand, C.; Pietrzyk, Z.A.; Reimerdes, H.; Ward, D.J. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1997-06-01

    One of the principal aims of TCV is the creation and active stabilization of highly elongated plasmas, {kappa}{>=}3. This implies high growth rates of axisymmetric modes and a very low stability margin. To stabilize such modes, TCV is equipped with a vertical position control system using a combination of slow coils outside the vacuum vessel (response time {approx_equal}1 ms) and a fast coil inside the vessel (response time {approx_equal}0.2 ms). The fast coil became operational in August 1996 and this paper describes the first experiments using both fast and slow coils for vertical stabilization. (author) 4 figs., 8 refs.

  15. Plasma-Assisted Chemistry in High-Speed Flow

    Institute of Scientific and Technical Information of China (English)

    Sergey B.LEONOV; Dmitry A.YARANTSEV; Anatoly P.NAPARTOVICH; Igor V.KOCHETOV

    2007-01-01

    Fundamental problems related to the high-speed combustion are analyzed. The result of plasma-chemical modeling is presented as a motivation of experimental activity.Numerical simulations of the effect of uniform non-equilibrium discharge on the premixed hydrogen and ethylene-air mixture in supersonic flow demonstrate an advantage of such a technique over a heating.Experimental results on multi-electrode non-uniform discharge maintenance behind wallstep and in cavity of supersonic flow are presented.The model test on hydrogen and ethylene ignition is demonstrated at direct fuel injection to low-temperature high-speed airflow.

  16. Treatment of Wastewater with High Conductivity by Pulsed Discharge Plasma

    Science.gov (United States)

    Wang, Zhaojun; Jiang, Song; Liu, Kefu

    2014-07-01

    A wastewater treatment system was established by means of pulsed dielectric barrier discharge (DBD). The main advantage of this system is that the wastewater is employed as one of the electrodes for the degradation of rhodamine B, which makes use of the high conductivity and lessenes its negative influence on the discharge process. At the same time, the reactive species like ozone and ultraviolet (UV) light generated by the DBD can be utilized for the treatment of wastewater. The effects of some factors like conductivity, peak pulse voltage, discharge frequency and pH values were investigated. The results show that the combination of these reactive species could enhance the degradation of the dye while the ozone played the most important role in the process. The degradation efficiency was enhanced with the increase of energy supplied. The reduction in the concentration of rhodamine B was much more effective with high solution conductivity; under the highest conductivity condition, the degradation rate could rise to 99%.

  17. Operational characteristics of the high flux plasma generator Magnum-PSI

    NARCIS (Netherlands)

    van Eck, H. J. N.; Abrams, T.; van den Berg, M. A.; Brons, S.; van Eden, G. G.; Jaworski, M. A.; Kaita, R.; van der Meiden, H. J.; Morgan, T. W.; van de Pol, M.J.; Scholten, J.; Smeets, P. H. M.; De Temmerman, G.; de Vries, P. C.; van Emmichoven, P. A. Zeijlma

    2014-01-01

    Abstract In Magnum-PSI (MAgnetized plasma Generator and \\{NUMerical\\} modeling for Plasma Surface Interactions), the high density, low temperature plasma of a wall stabilized dc cascaded arc is confined to a magnetized plasma beam by a quasi-steady state axial magnetic field up to 1.3 T. It

  18. Duty cycle control in reactive high-power impulse magnetron sputtering of hafnium and niobium

    Science.gov (United States)

    Ganesan, R.; Treverrow, B.; Murdoch, B.; Xie, D.; Ross, A. E.; Partridge, J. G.; Falconer, I. S.; McCulloch, D. G.; McKenzie, D. R.; Bilek, M. M. M.

    2016-06-01

    Instabilities in reactive sputtering have technological consequences and have been attributed to the formation of a compound layer on the target surface (‘poisoning’). Here we demonstrate how the duty cycle of high power impulse magnetron sputtering (HiPIMS) can be used to control the surface conditions of Hf and Nb targets. Variations in the time resolved target current characteristics as a function of duty cycle were attributed to gas rarefaction and to the degree of poisoning of the target surface. As the operation transitions from Ar driven sputtering to metal driven sputtering, the secondary electron emission changes and reduces the target current. The target surface transitions smoothly from a poisoned state at low duty cycles to a quasi-metallic state at high duty cycles. Appropriate selection of duty cycle increases the deposition rate, eliminates the need for active regulation of oxygen flow and enables stable reactive deposition of stoichiometric metal oxide films. A model is presented for the reactive HIPIMS process in which the target operates in a partially poisoned mode with different degrees of oxide layer distribution on its surface that depends on the duty cycle. Finally, we show that by tuning the pulse characteristics, the refractive indices of the metal oxides can be controlled without increasing the absorption coefficients, a result important for the fabrication of optical multilayer stacks.

  19. A cold plasma plume with a highly conductive liquid electrode

    Institute of Scientific and Technical Information of China (English)

    Chen Guang-Liang; Chen Shi-gua; Chen Wen-Xing; Yang Si-Ze

    2008-01-01

    A cold dielectric barrier discharge (DBD) plasma plume with one highly conductive liquid electrode has been developed to treat thermally sensitive materials, and its preliminary discharging characteristics have been studied. The averaged electron temperature and density is estimated to be 0.6eV and 1011/cm3, respectively. The length of plasma plume can reach 5cm with helium gas (He), and the conductivity of the outer electrode affects the plume length obviously. This plasma plume could be touched by bare hand without causing any burning or painful sensation,which may provide potential application for safe aseptic skin care. Moreover, the oxidative particles (e.g., OH, O*03) in the downstream oxygen (02) gas of the plume have been applied to treat the landfill leachate. The results show that the activated 02 gas can degrade the landfill leachate effectively, and the chemical oxygen demand (COD),conductivity, biochemical oxygen demand (BOD), and suspended solid (SS) can be decreased by 52%, 57%, 76% and 92%, respectively.

  20. Interleukin-1 Blockade With Canakinumab to Improve Exercise Capacity in Patients With Chronic Systolic Heart Failure and Elevated High Sensitivity C-reactive Protein (Hs-CRP)

    Science.gov (United States)

    2017-09-14

    Prior Acute Myocardial Infarction; Evidence of Systemic Inflammation (C Reactive Protein Plasma >2 mg/l); Reduced Left Ventricle Ejection Fraction (<50%); Symptoms of Heart Failure (NYHA Class II-III)

  1. Instrument technology for magnetosphere plasma imaging from high Earth orbit. Design of a radio plasma sounder

    Science.gov (United States)

    Haines, D. Mark; Reinisch, Bodo W.

    1995-01-01

    The use of radio sounding techniques for the study of the ionospheric plasma dates back to G. Briet and M. A. Tuve in 1926. Ground based swept frequency sounders can monitor the electron number density (N(sub e)) as a function of height (the N(sub e) profile). These early instruments evolved into a global network that produced high-resolution displays of echo time delay vs frequency on 35-mm film. These instruments provided the foundation for the success of the International Geophysical Year (1958). The Alouette and International Satellites for Ionospheric Studies (ISIS) programs pioneered the used of spaceborne, swept frequency sounders to obtain N(sub e) profiles of the topside of the ionosphere, from a position above the electron density maximum. Repeated measurements during the orbit produced an orbital plane contour which routinely provided density measurements to within 10%. The Alouette/ISIS experience also showed that even with a high powered transmitter (compared to the low power sounder possible today) a radio sounder can be compatible with other imaging instruments on the same satellite. Digital technology was used on later spacecraft developed by the Japanese (the EXOS C and D) and the Soviets (Intercosmos 19 and Cosmos 1809). However, a full coherent pulse compression and spectral integrating capability, such as exist today for ground-based sounders (Reinisch et al., 1992), has never been put into space. NASA's 1990 Space Physics Strategy Implementation Study "The NASA Space Physics Program from 1995 to 2010" suggested using radio sounders to study the plasmasphere and the magnetopause and its boundary layers (Green and Fung, 1993). Both the magnetopause and plasmasphere, as well as the cusp and boundary layers, can be observed by a radio sounder in a high-inclination polar orbit with an apogee greater than 6 R(sub e) (Reiff et al., 1994; Calvert et al., 1995). Magnetospheric radio sounding from space will provide remote density measurements of

  2. High Ki-67 Immunohistochemical Reactivity Correlates With Poor Prognosis in Bladder Carcinoma

    Science.gov (United States)

    Luo, Yihuan; Zhang, Xin; Mo, Meile; Tan, Zhong; Huang, Lanshan; Zhou, Hong; Wang, Chunqin; Wei, Fanglin; Qiu, Xiaohui; He, Rongquan; Chen, Gang

    2016-01-01

    Abstract Ki-67 is considered as one of prime biomarkers to reflect cell proliferation and immunohistochemical Ki-67 staining has been widely applied in clinical pathology. To solve the widespread controversy whether Ki-67 reactivity significantly predicts clinical prognosis of bladder carcinoma (BC), we performed a comprehensive meta-analysis by combining results from different literature. A comprehensive search was conducted in the Chinese databases of WanFang, China National Knowledge Infrastructure and Chinese VIP as well as English databases of PubMed, ISI web of science, EMBASE, Science Direct, and Wiley online library. Independent studies linking Ki-67 to cancer-specific survival (CSS), disease-free survival (DFS), overall survival (OS), progression-free survival (PFS), and recurrence-free survival (RFS) were included in our meta-analysis. With the cut-off values literature provided, hazard ratio (HR) values between the survival distributions were extracted and later combined with STATA 12.0. In total, 76 studies (n = 13,053 patients) were eligible for the meta-analysis. It was indicated in either univariate or multivariate analysis for survival that high Ki-67 reactivity significantly predicted poor prognosis. In the univariate analysis, the combined HR for CSS, DFS, OS, PFS, and RFS were 2.588 (95% confidence interval [CI]: 1.623–4.127, P < 0.001), 2.697 (95%CI: 1.874–3.883, P < 0.001), 2.649 (95%CI: 1.632–4.300, P < 0.001), 3.506 (95%CI: 2.231–5.508, P < 0.001), and 1.792 (95%CI: 1.409–2.279, P < 0.001), respectively. The pooled HR of multivariate analysis for CSS, DFS, OS, PFS, and RFS were 1.868 (95%CI: 1.343–2.597, P < 0.001), 2.626 (95%CI: 2.089–3.301, P < 0.001), 1.104 (95%CI: 1.008–1.209, P = 0.032), 1.518 (95%CI: 1.299–1.773, P < 0.001), and 1.294 (95%CI: 1.203–1.392, P < 0.001), respectively. Subgroup analysis of univariate analysis by origin showed that Ki-67 reactivity significantly

  3. Exploration of Plasma Jets Approach to High Energy Density Physics. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chiping [Massachusetts Institute of Technology

    2013-08-26

    High-energy-density laboratory plasma (HEDLP) physics is an emerging, important area of research in plasma physics, nuclear physics, astrophysics, and particle acceleration. While the HEDLP regime occurs at extreme conditions which are often found naturally in space but not on the earth, it may be accessible by colliding high intensity plasmas such as high-energy-density plasma jets, plasmoids or compact toroids from plasma guns. The physics of plasma jets is investigated in the context of high energy density laboratory plasma research. This report summarizes results of theoretical and computational investigation of a plasma jet undergoing adiabatic compression and adiabatic expansion. A root-mean-squared (rms) envelope theory of plasma jets is developed. Comparison between theory and experiment is made. Good agreement between theory and experiment is found.

  4. SiNx coatings deposited by reactive high power impulse magnetron sputtering: Process parameters influencing the residual coating stress

    Science.gov (United States)

    Schmidt, S.; Hänninen, T.; Wissting, J.; Hultman, L.; Goebbels, N.; Santana, A.; Tobler, M.; Högberg, H.

    2017-05-01

    The residual coating stress and its control is of key importance for the performance and reliability of silicon nitride (SiNx) coatings for biomedical applications. This study explores the most important deposition process parameters to tailor the residual coating stress and hence improve the adhesion of SiNx coatings deposited by reactive high power impulse magnetron sputtering (rHiPIMS). Reactive sputter deposition and plasma characterization were conducted in an industrial deposition chamber equipped with pure Si targets in N2/Ar ambient. Reactive HiPIMS processes using N2-to-Ar flow ratios of 0 and 0.28-0.3 were studied with time averaged positive ion mass spectrometry. The coatings were deposited to thicknesses of 2 μm on Si(001) and to 5 μm on polished CoCrMo disks. The residual stress of the X-ray amorphous coatings was determined from the curvature of the Si substrates as obtained by X-ray diffraction. The coatings were further characterized by X-ray photoelectron spectroscopy, scanning electron microscopy, and nanoindentation in order to study their elemental composition, morphology, and hardness, respectively. The adhesion of the 5 μm thick coatings deposited on CoCrMo disks was assessed using the Rockwell C test. The deposition of SiNx coatings by rHiPIMS using N2-to-Ar flow ratios of 0.28 yield dense and hard SiNx coatings with Si/N ratios <1. The compressive residual stress of up to 2.1 GPa can be reduced to 0.2 GPa using a comparatively high deposition pressure of 600 mPa, substrate temperatures below 200 °C, low pulse energies of <2.5 Ws, and moderate negative bias voltages of up to 100 V. These process parameters resulted in excellent coating adhesion (ISO 0, HF1) and a low surface roughness of 14 nm for coatings deposited on CoCrMo.

  5. Design of Plasma Generator Driven by High-frequency High-voltage Power Supply

    Directory of Open Access Journals (Sweden)

    C. Yong-Nong

    2013-03-01

    Full Text Available In this research, a high-frequency high-voltage power supply designed for plasma generator is presented. The powersupply mainly consists of a series resonant converter with a high-frequency high-voltage boost transformer. Due to theindispensable high-voltage inheritance in the operation of plasma generator, the analysis of transformer needconsidering not only winding resistance, leakage inductance, magnetizing inductance, and core-loss resistance, butalso parasitic capacitance resulted from the insulation wrappings on the high-voltage side. This research exhibits asimple approach to measuring equivalent circuit parameters of the high-frequency, high-voltage transformer with straycapacitance being introduced into the conventional modeling. The proposed modeling scheme provides not only aprecise measurement procedure but also effective design information for series-load resonant converter. The plasmadischarging plate is designed as part of the electric circuit in the series load-resonant converter and the circuit modelof the plasma discharging plate is also conducted as well. Thus, the overall model of the high-voltage plasmagenerator is built and the designing procedures for appropriate selections of the corresponding resonant-circuitparameters can be established. Finally, a high-voltage plasma generator with 220V, 60Hz, and 1kW input, along witha 22 kHz and over 8kV output, is realized and implemented.

  6. High density plasmas and new diagnostics: An overview (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Celona, L., E-mail: celona@lns.infn.it; Gammino, S.; Mascali, D. [Istituto Nazionale di Fisica Nucleare—Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy)

    2016-02-15

    One of the limiting factors for the full understanding of Electron Cyclotron Resonance Ion Sources (ECRISs) fundamental mechanisms consists of few types of diagnostic tools so far available for such compact machines. Microwave-to-plasma coupling optimisation, new methods of density overboost provided by plasma wave generation, and magnetostatic field tailoring for generating a proper electron energy distribution function, suitable for optimal ion beams formation, require diagnostic tools spanning across the entire electromagnetic spectrum from microwave interferometry to X-ray spectroscopy; these methods are going to be implemented including high resolution and spatially resolved X-ray spectroscopy made by quasi-optical methods (pin-hole cameras). The ion confinement optimisation also requires a complete control of cold electrons displacement, which can be performed by optical emission spectroscopy. Several diagnostic tools have been recently developed at INFN-LNS, including “volume-integrated” X-ray spectroscopy in low energy domain (2-30 keV, by using silicon drift detectors) or high energy regime (>30 keV, by using high purity germanium detectors). For the direct detection of the spatially resolved spectral distribution of X-rays produced by the electronic motion, a “pin-hole camera” has been developed also taking profit from previous experiences in the ECRIS field. The paper will give an overview of INFN-LNS strategy in terms of new microwave-to-plasma coupling schemes and advanced diagnostics supporting the design of new ion sources and for optimizing the performances of the existing ones, with the goal of a microwave-absorption oriented design of future machines.

  7. High density plasmas and new diagnostics: An overview (invited).

    Science.gov (United States)

    Celona, L; Gammino, S; Mascali, D

    2016-02-01

    One of the limiting factors for the full understanding of Electron Cyclotron Resonance Ion Sources (ECRISs) fundamental mechanisms consists of few types of diagnostic tools so far available for such compact machines. Microwave-to-plasma coupling optimisation, new methods of density overboost provided by plasma wave generation, and magnetostatic field tailoring for generating a proper electron energy distribution function, suitable for optimal ion beams formation, require diagnostic tools spanning across the entire electromagnetic spectrum from microwave interferometry to X-ray spectroscopy; these methods are going to be implemented including high resolution and spatially resolved X-ray spectroscopy made by quasi-optical methods (pin-hole cameras). The ion confinement optimisation also requires a complete control of cold electrons displacement, which can be performed by optical emission spectroscopy. Several diagnostic tools have been recently developed at INFN-LNS, including "volume-integrated" X-ray spectroscopy in low energy domain (2-30 keV, by using silicon drift detectors) or high energy regime (>30 keV, by using high purity germanium detectors). For the direct detection of the spatially resolved spectral distribution of X-rays produced by the electronic motion, a "pin-hole camera" has been developed also taking profit from previous experiences in the ECRIS field. The paper will give an overview of INFN-LNS strategy in terms of new microwave-to-plasma coupling schemes and advanced diagnostics supporting the design of new ion sources and for optimizing the performances of the existing ones, with the goal of a microwave-absorption oriented design of future machines.

  8. Apolipoprotein modulation of streptococcal serum opacity factor activity against human plasma high-density lipoproteins.

    Science.gov (United States)

    Rosales, Corina; Gillard, Baiba K; Courtney, Harry S; Blanco-Vaca, Francisco; Pownall, Henry J

    2009-08-25

    Human plasma HDL are the target of streptococcal serum opacity factor (SOF), a virulence factor that clouds human plasma. Recombinant (r) SOF transfers cholesteryl esters (CE) from approximately 400,000 HDL particles to a CE-rich microemulsion (CERM), forms a cholesterol-poor HDL-like particle (neo HDL), and releases lipid-free (LF) apo A-I. Whereas the rSOF reaction requires labile apo A-I, the modulation effects of other apos are not known. We compared the products and rates of the rSOF reaction against human HDL and HDL from mice overexpressing apos A-I and A-II. Kinetic studies showed that the reactivity of various HDL species is apo-specific. LpA-I reacts faster than LpA-I/A-II. Adding apos A-I and A-II inhibited the SOF reaction, an effect that was more profound for apo A-II. The rate of SOF-mediated CERM formation was slower against HDL from mice expressing human apos A-I and A-II than against WT mice HDL and slowest against HDL from apo A-II overexpressing mice. The lower reactivity of SOF against HDL containing human apos is due to the higher hydropathy of human apo A-I, particularly its C-terminus relative to mouse apo A-I, and the higher lipophilicity of human apo A-II. The SOF-catalyzed reaction is the first to target HDL rather than its transporters and receptors in a way that enhances reverse cholesterol transport (RCT). Thus, effects of apos on the SOF reaction are highly relevant. Our studies show that the "humanized" apo A-I-expressing mouse is a good animal model for studies of rSOF effects on RCT in vivo.

  9. Quantification of tryptophan in plasma by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Renata Romanholi Pinhati

    2012-01-01

    Full Text Available A simple, rapid and selective method using high-performance liquid chromatography with ultraviolet detection (267 nm was applied for the determination of tryptophan in plasma. Separation was carried out on a C18 column (150 x 4.6 mm internal diameter in 6 min. The mobile phase consisted of 5 mM the sodium acetate and acetonitrile (92:8, v/v. The method was shown to be precise and accurate, and good recovery of analyte was achieved, characterizing the method as efficient and reliable for use in laboratory analysis.

  10. Radial convection of finite ion temperature, high amplitude plasma blobs

    DEFF Research Database (Denmark)

    Wiesenberger, M.; Madsen, Jens; Kendl, Alexander

    2014-01-01

    We present results from simulations of seeded blob convection in the scrape-off-layer of magnetically confined fusion plasmas. We consistently incorporate high fluctuation amplitude levels and finite Larmor radius (FLR) effects using a fully nonlinear global gyrofluid model. This is in line...... with conditions found in tokamak scrape-off-layers (SOL) regions. Varying the ion temperature, the initial blob width, and the initial amplitude, we found an FLR dominated regime where the blob behavior is significantly different from what is predicted by cold-ion models. The transition to this regime is very...

  11. Simulation of transition dynamics to high confinement in fusion plasmas

    CERN Document Server

    Nielsen, A H; Madsen, J; Naulin, V; Rasmussen, J Juul; Wan, B N

    2014-01-01

    The transition dynamics from the low (L) to the high (H) confinement mode in magnetically confined plasmas is investigated using a first-principles four-field fluid model. Numerical results are in close agreement with measurements from the Experimental Advanced Superconducting Tokamak - EAST. Particularly, the slow transition with an intermediate dithering phase is well reproduced by the numerical solutions. Additionally, the model reproduces the experimentally determined L-H transition power threshold scaling that the ion power threshold increases with increasing particle density. The results hold promise for developing predictive models of the transition, essential for understanding and optimizing future fusion power reactors.

  12. High-Frequency-Induced Cathodic Breakdown during Plasma Electrolytic Oxidation

    Science.gov (United States)

    Nominé, A.; Nominé, A. V.; Braithwaite, N. St. J.; Belmonte, T.; Henrion, G.

    2017-09-01

    The present communication shows the possibility of observing microdischarges under cathodic polarization during plasma electrolytic oxidation at high frequency. Cathodic microdischarges can ignite beyond a threshold frequency found close to 2 kHz. The presence (respectively, absence) of an electrical double layer is put forward to explain how the applied voltage can be screened, which therefore prevents (respectively, promotes) the ignition of a discharge. Interestingly, in the conditions of the present study, the electrical double layer requires between 175 and 260 μ s to form. This situates the expected threshold frequency between 1.92 and 2.86 kHz, which is in good agreement with the value obtained experimentally.

  13. Return of target material ions leads to a reduced hysteresis in reactive high power impulse magnetron sputtering: Model

    Science.gov (United States)

    Kadlec, Stanislav; Čapek, Jiří

    2017-05-01

    A tendency to disappearing hysteresis in reactive High Power Impulse Magnetron Sputtering (HiPIMS) has been reported previously without full physical explanation. An analytical model of reactive pulsed sputtering including HiPIMS is presented. The model combines a Berg-type model of reactive sputtering with the global HiPIMS model of Christie-Vlček. Both time and area averaging is used to describe the macroscopic steady state, especially the reactive gas balance in the reactor. The most important effect in the presented model is covering of reacted parts of target by the returning ionized metal, effectively lowering the target coverage by reaction product at a given partial pressure. The return probability of ionized sputtered metal has been selected as a parameter to quantify the degree of HiPIMS effects. The model explains the reasons for reduced hysteresis in HiPIMS. The critical pumping speed was up to a factor of 7 lower in reactive HiPIMS compared to the mid-frequency magnetron sputtering. The model predicts reduced hysteresis in HiPIMS due to less negative slope of metal flux to substrates and of reactive gas sorption as functions of reactive gas partial pressure. Higher deposition rate of reactive HiPIMS compared to standard reactive sputtering is predicted for some parameter combinations. Comparison of the model with experiment exhibits good qualitative and quantitative agreement for three material combinations, namely, Ti-O2, Al-O2, and Ti-N2.

  14. Analytical estimation of control rod shadowing effect for excess reactivity measurement of High Temperature Engineering Test Reactor (HTTR)

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Masaaki; Yamashita, Kiyonobu; Fujimoto, Nozomu; Nojiri, Naoki; Takeuchi, Mitsuo; Fujisaki, Shingo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Tokuhara, Kazumi; Nakata, Tetsuo

    1998-05-01

    The control rod shadowing effect has been estimated analytically in application of the fuel addition method to excess reactivity measurement of High Temperature Engineering Test Reactor (HTTR). The movements of control rods in the procedure of the fuel addition method have been simulated in the analysis. The calculated excess reactivity obtained by the simulation depends on the combinations of measuring control rods and compensating control rods and varies from -10% to +50% in comparison with the excess reactivity calculated from the effective multiplication factor of the core where all control rods are fully withdrawn. The control rod shadowing effect is reduced by the use of plural number of measuring and compensation control rods because of the reduction in neutron flux deformation in the measuring procedure. As a result, following combinations of control rods are recommended; 1) Thirteen control rods of the center, first, and second rings will be used for the reactivity measurement. The reactivity of each control rod is measured by the use of the other twelve control rods for reactivity compensation. 2) Six control rods of the first ring will be used for the reactivity measurement. The reactivity of each control rod is measured by the use of the other five control rods for reactivity compensation. (author)

  15. High plasma uric acid concentration: causes and consequences

    Directory of Open Access Journals (Sweden)

    de Oliveira Erick

    2012-04-01

    Full Text Available Abstract High plasma uric acid (UA is a precipitating factor for gout and renal calculi as well as a strong risk factor for Metabolic Syndrome and cardiovascular disease. The main causes for higher plasma UA are either lower excretion, higher synthesis or both. Higher waist circumference and the BMI are associated with higher insulin resistance and leptin production, and both reduce uric acid excretion. The synthesis of fatty acids (tryglicerides in the liver is associated with the de novo synthesis of purine, accelerating UA production. The role played by diet on hyperuricemia has not yet been fully clarified, but high intake of fructose-rich industrialized food and high alcohol intake (particularly beer seem to influence uricemia. It is not known whether UA would be a causal factor or an antioxidant protective response. Most authors do not consider the UA as a risk factor, but presenting antioxidant function. UA contributes to > 50% of the antioxidant capacity of the blood. There is still no consensus if UA is a protective or a risk factor, however, it seems that acute elevation is a protective factor, whereas chronic elevation a risk for disease.

  16. Observation of a periodic runaway in the reactive Ar/O{sub 2} high power impulse magnetron sputtering discharge

    Energy Technology Data Exchange (ETDEWEB)

    Shayestehaminzadeh, Seyedmohammad, E-mail: ses30@hi.is, E-mail: shayesteh@mch.rwth-aachen.de; Arnalds, Unnar B.; Magnusson, Rögnvaldur L.; Olafsson, Sveinn [Science Institute, University of Iceland, Dunhaga 3, IS-107 Reykjavik (Iceland)

    2015-11-15

    This paper reports the observation of a periodic runaway of plasma to a higher density for the reactive discharge of the target material (Ti) with moderate sputter yield. Variable emission of secondary electrons, for the alternating transition of the target from metal mode to oxide mode, is understood to be the main reason for the runaway occurring periodically. Increasing the pulsing frequency can bring the target back to a metal (or suboxide) mode, and eliminate the periodic transition of the target. Therefore, a pulsing frequency interval is defined for the reactive Ar/O{sub 2} discharge in order to sustain the plasma in a runaway-free mode without exceeding the maximum power that the magnetron can tolerate.

  17. Changes of serum high sensitive C-reactive protein in patients with acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Yan Du; Yan Ren; Ying Li

    2007-01-01

    BACKGROUND: Serum high sensitive C-reactive protein (hs-CRP), which regards as a high sensitive mark of systemic inflammatory response syndrome, can provide a lot of valuable information for the treatment and prognosis of cerebrovascular disease.OBJECTIVE: To observe the differences of blood glucose, lipid, homocysteine and previous disease history among patients with acute cerebral infarction at various levels of hs-CRP and compare changes of hs-CRP of patients with various degrees ofneurologic impairment.DESIGN: Contrast observation.SETTING: Department of Neurology, Shenzhou Hospital, Shenyang Medical College.PARTICIPANTS: A total of 102 patients with acute cerebral infarction were selected from Department of Neurology, Shenzhou Hospital of Shenyang Medical College from February 2005 to September 2006,including 55 males and 47 females aged from 55 to 86 years. All accepted patients met the diagnostic criteria of cerebral infarction established by the Fourth National Cerebrovascular Disease Academic Meeting and were diagnosed with CT or MRI examination. All patients provided the confirmed consent. Based on clinical criteria of neurologic impairment established by the Fourth National Cerebrovascular Disease Academic Meeting, patients were randomly divided into mild group (0- 15 points, n =46), moderate group (16- 30points, n =38) and severe group (31 - 45 points, n =18). In addition, based on hs-CRP level within 72 hours,patients were divided into normal group (hs-CRP ≤ 3 mg/L, n =53) and increasing group (hs-CRP > 3 mg/L,n =49).METHODS: ① 2 mL venous blood was selected from hospitalized patients in the next morning to separate serum. Quantitative measurement of hs-CRP was dealt with Latex Enhnced Turbidimetric Immunoassay (LETIA). ② Fasting venous blood was colleted from hospitalized patients in the next morning to measure numeration of white blood cells, fibrinogen, blood glucose, total cholesterol (TC), triacylglycerol (TG), high density lipoprotein

  18. High fluence laser irradiation induces reactive oxygen species generation in human lung adenocarcinoma cells

    Science.gov (United States)

    Wang, Fang; Xing, Da; Chen, Tong-Sheng

    2006-09-01

    Low-power laser irradiation (LPLI) has been used for therapies such as curing spinal cord injury, healing wound et al. Yet, the mechanism of LPLI remains unclear. Our previous study showed that low fluences laser irradiation induces human lung adenocarcinoma cells (ASTC-a-1) proliferation, but high fluences induced apoptosis and caspase-3 activation. In order to study the mechanism of apoptosis induced by high fluences LPLI further, we have measured the dynamics of generation of reactive oxygen species (ROS) using H IIDCFDA fluorescence probes during this process. ASTC-a-1 cells apoptosis was induced by He-Ne laser irradiation at high fluence of 120J/cm2. A confocal laser scanning microscope was used to perform fluorescence imaging. The results demonstrated that high fluence LPLI induced the increase of mitochondria ROS. Our studies contribute to clarify the biological mechanism of high fluence LPLI-induced cell apoptosis.

  19. Neither perceived job stress nor individual cardiovascular reactivity predict high blood pressure.

    Science.gov (United States)

    Fauvel, Jean Pierre; M'Pio, Ignasse; Quelin, Pierre; Rigaud, Jean-Pierre; Laville, Maurice; Ducher, Michel

    2003-12-01

    We have reported that high job strain was associated with a significantly higher diastolic blood pressure (DBP) of 4.5 mm Hg during the working hours, irrespective of BP reactivity to a stress test. We report the final results of the first 5-year follow-up study, which aimed to assess the respective influences of perception of professional strain and cardiovascular reactivity to a mental stress test on BP. A cohort of 292 healthy subjects (mean+/-SEM age, 38+/-1 years) was followed up for progression to hypertension outcome, which was defined as an increase in systolic blood pressure (SBP) or DBP >7 mm Hg or a DBP >95 mm Hg during follow-up. None of the subjects was lost to follow-up, and 209 subjects completed the study. The high-strain (HS) group, representing 20.9% of the subjects, was compared with the remaining subjects (non-high-strain [NHS]). Similarly, the subjects with the highest BP stress reactivity (HR; 20.9% of subjects) were compared with the remaining subjects (NHR). Progression to hypertension was reached by 93 subjects (31.8%). Kaplan-Meier survival estimates revealed that neither HS nor HR increased the incidence of progression to hypertension. End-of-follow-up 24-hour ambulatory BPs that were similar in HS and NHS (120+/-2 vs 120+/-1 mm Hg, respectively) and in HR and NHR (122+/-2 vs 120+/-1 mm Hg, respectively) confirmed our findings. Age, alcohol, salt diet, body mass index, and occupation did not interfere with our results. In conclusion, cardiovascular HR and HS do not appear to be major risk markers for future high BP in healthy, young adults.

  20. High temperature superconductors for fusion at the Swiss Plasma Center

    Science.gov (United States)

    Bruzzone, P.; Wesche, R.; Uglietti, D.; Bykovsky, N.

    2017-08-01

    High temperature superconductors (HTS) may become in future an option for the superconducting magnets of commercial fusion plants. At the Swiss Plasma Center (SPC) the R&D activity toward HTS high current, high field cables suitable for fusion magnets started in 2012 and led in 2015 to the assembly of the first 60 kA, 12 T prototype conductor. The cable concept developed at the SPC is based on the principle of ‘soldered, twisted stacks’ of REBCO tapes. The required number of stacks is assembled in a cored flat cable, cooled by forced flow of supercritical helium. The sample environment of the test facility at SPC has been upgraded with a HTS adapter and a counter-flow heat exchanger to allow testing the HTS sample in a broader range of temperature (4.5 K-50 K) using the existing, NbTi based superconducting transformer and the closed loop refrigerator.

  1. Roles of charged particles and reactive species on cell membrane permeabilization induced by atmospheric-pressure plasma irradiation

    Science.gov (United States)

    Sasaki, Shota; Kanzaki, Makoto; Hokari, Yutaro; Tominami, Kanako; Mokudai, Takayuki; Kanetaka, Hiroyasu; Kaneko, Toshiro

    2016-07-01

    As factors that influence cell membrane permeabilization during direct and indirect atmospheric-pressure plasma irradiation, charged particle influx, superoxide anion radicals (O2 -•), and hydrogen peroxide (H2O2) in plasma-irradiated solution were evaluated. These are the three strong candidate factors and might multiply contribute to cell membrane permeabilization. In particular, a shorter plasma diffusion distance leads to the enhancement of the direct effects such as charged particle influx and further increase cell membrane permeability. In addition, O2 -• dissipates over time (a life span of the order of minutes) in plasma-irradiated water, and the deactivation of a plasma-irradiated solution in term of cell membrane permeabilization occurs in a life span of the same order. These results could promote the understanding of the mechanism of plasma-induced cell membrane permeabilization.

  2. High current multicharged metal ion source using high power gyrotron heating of vacuum arc plasma.

    Science.gov (United States)

    Vodopyanov, A V; Golubev, S V; Khizhnyak, V I; Mansfeld, D A; Nikolaev, A G; Oks, E M; Savkin, K P; Vizir, A V; Yushkov, G Yu

    2008-02-01

    A high current, multi charged, metal ion source using electron heating of vacuum arc plasma by high power gyrotron radiation has been developed. The plasma is confined in a simple mirror trap with peak magnetic field in the plug up to 2.5 T, mirror ratio of 3-5, and length variable from 15 to 20 cm. Plasma formed by a cathodic vacuum arc is injected into the trap either (i) axially using a compact vacuum arc plasma gun located on axis outside the mirror trap region or (ii) radially using four plasma guns surrounding the trap at midplane. Microwave heating of the mirror-confined, vacuum arc plasma is accomplished by gyrotron microwave radiation of frequency 75 GHz, power up to 200 kW, and pulse duration up to 150 micros, leading to additional stripping of metal ions by electron impact. Pulsed beams of platinum ions with charge state up to 10+, a mean charge state over 6+, and total (all charge states) beam current of a few hundred milliamperes have been formed.

  3. Electromagnetic gyrokinetic turbulence in high-beta helical plasmas

    Science.gov (United States)

    Ishizawa, Akihiro

    2013-10-01

    Gyrokinetic simulation of electromagnetic turbulence in finite-beta plasmas is important for predicting the performance of fusion reactors. Whereas in low-beta tokamaks the zonal flow shear acts to regulate ion temperature gradient (ITG) driven turbulence, it has often been observed that the kinetic ballooning mode (KBM) and, at moderate-beta, the ITG mode continue to grow without reaching a physically relevant level of saturation. The corresponding problem in helical high-beta plasmas, the identification of a saturation mechanism for microturbulence in regimes where zonal flow generation is too weak, is the subject of the present work. This problem has not been previously explored because of numerical difficulties associated with complex three-dimensional magnetic structures as well as multiple spatio-temporal scales related to electromagnetic ion and electron dynamics. The present study identifies a new saturation process of the KBM turbulence originating from the spatial structure of the KBM instabilities in a high-beta Large Helical Device (LHD) plasma. Specifically, the most unstable KBM in LHD has an inclined mode structure with respect to the mid-plane of a torus, i.e. it has finite radial wave-number in flux tube coordinates, in contrast to KBMs in tokamaks as well as ITG modes in tokamaks and helical systems. The simulations reveal that the growth of KBMs in LHD is saturated by nonlinear interactions of oppositely inclined convection cells through mutual shearing, rather than by the zonal flow shear. The mechanism is quantitatively evaluated by analysis of the nonlinear entropy transfer.

  4. High duty factor plasma generator for CERN's Superconducting Proton Linac.

    Science.gov (United States)

    Lettry, J; Kronberger, M; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, J-M; Küchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

    2010-02-01

    CERN's Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN's PS-Booster. Its ion source is a noncesiated rf driven H(-) volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H(-) during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the Large Hadron Collider. It consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H(-) during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H(-) plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the required heat dissipation and maintains the original functionality. Materials with higher thermal conductivity are selected and, wherever possible, thermal barriers resulting from low pressure contacts are removed by brazing metals on insulators. The AlN plasma chamber cooling circuit is inspired from the approach chosen for the cesiated high duty factor rf H(-) source operating at SNS.

  5. Developments in plasma enhanced spatial ALD for high throughput applications [3.04

    NARCIS (Netherlands)

    Creyghton, Y.; Illiberi, A.; Mione, M.; Boekel, W. van; Debernardi, N.; Seitz, M.; Bruele, F. van den; Poodt, P.; Roozeboom,F.

    2016-01-01

    Atomic layer deposition by means of spatial separation of reactive gases is emerging as an industrial manufacturing technology. Integration of non-thermal plasma in spatial ALD machines will further expand the process window towards lower operation temperatures and specific materials requiring radic

  6. High-field plasma acceleration in a high-ionization-potential gas.

    Science.gov (United States)

    Corde, S; Adli, E; Allen, J M; An, W; Clarke, C I; Clausse, B; Clayton, C E; Delahaye, J P; Frederico, J; Gessner, S; Green, S Z; Hogan, M J; Joshi, C; Litos, M; Lu, W; Marsh, K A; Mori, W B; Vafaei-Najafabadi, N; Walz, D; Yakimenko, V

    2016-06-17

    Plasma accelerators driven by particle beams are a very promising future accelerator technology as they can sustain high accelerating fields over long distances with high energy efficiency. They rely on the excitation of a plasma wave in the wake of a drive beam. To generate the plasma, a neutral gas can be field-ionized by the head of the drive beam, in which case the distance of acceleration and energy gain can be strongly limited by head erosion. Here we overcome this limit and demonstrate that electrons in the tail of a drive beam can be accelerated by up to 27 GeV in a high-ionization-potential gas (argon), boosting their initial 20.35 GeV energy by 130%. Particle-in-cell simulations show that the argon plasma is sustaining very high electric fields, of ∼150 GV m(-1), over ∼20 cm. The results open new possibilities for the design of particle beam drivers and plasma sources.

  7. Reactive Fusion Welding for Ultra-High Temperature Ceramic Composite Joining

    Science.gov (United States)

    2015-03-16

    INTRODUCTION Zirconium diboride (ZrB2) is ceramic material belonging to the group of materials known as ultra-high temperature ceramics (UHTCs), where UHTCs...expended during the diffusion of C from the graphite spacer. This occurs as the enthalpy of fusion (Hf) and mixing (Hmix) are expected to be positive...ZrB2 Ceramics ( Contributed Oral Presentation) Authors: Derek King, Greg E. Hilmas, and William G. Fahrenholtz Plasma arc welding was used to join

  8. Plasma diagnostics of an Ar/NH{sub 3} direct-current reactive magnetron sputtering discharge for SiN{sub x} deposition

    Energy Technology Data Exchange (ETDEWEB)

    Henry, F., E-mail: Fhenry@ulb.ac.be; Duluard, C.Y.; Batan, A.; Reniers, F., E-mail: Freniers@ulb.ac.be

    2012-08-01

    We have performed the deposition of silicon nitride thin films with the DC reactive magnetron sputtering technique from a silicon target in an Ar/NH{sub 3} gas mixture. Usually, the control of the process is carried out with discharge voltage measurements, which give information on the nature of the sputtering mode: metallic or reactive. To have a more complete view of the sputtering process, we have performed X-ray photoelectron spectroscopy (XPS) to investigate the chemistry of the silicon target racetrack and optical emission spectroscopy (OES) to investigate the Ar/NH{sub 3} gas phase near the target surface. When the NH{sub 3} molar fraction is increased, XPS measurements reveal the progressive formation of a silicon nitride layer on the target surface, thereby demonstrating a continuous transition to the reactive mode. OES measurements have highlighted the presence of several species which, according to the literature, are believed to be directly sputtered from the surface of the target: Si, SiH and SiN. Their intensities could be related to the chemical state of the target surface and provide a better insight into the sputtering process on the target surface. - Highlights: Black-Right-Pointing-Pointer Plasma diagnostics of Ar/NH{sub 3} DC reactive magnetron sputtering. Black-Right-Pointing-Pointer Multiple diagnostic techniques. Black-Right-Pointing-Pointer Poisoning of the target by formation of silicon nitride layer. Black-Right-Pointing-Pointer Relation between the light emitted by the plasma and the surface state of the target.

  9. Plasma Processes : Arc root dynamics in high power plasma torches – Evidence of chaotic behavior

    Indian Academy of Sciences (India)

    A K Das

    2000-11-01

    Although plasma torches have been commercially available for about 50 years, areas such as plasma gun design, process efficiency, reproducibility, plasma stability, torch lives etc. have remained mostly unattended. Recent torch developments have been focusing on the basic understanding of the plasma column and its dynamics inside the plasma torch, the interaction of plasma jet and the powders, the interaction of the plasma jet with surroundings and the impingement of the jet on the substrate. Two of the major causes of erratic and poor performance of a variety of thermal plasma processes are currently identified as the fluctuations arising out of the arc root movement on the electrodes inside the plasma torch and the fluid dynamic instabilities arising out of entrainment of the air into the plasma jet. This paper reviews the current state of understanding of these fluctuations as well as the dynamics of arc root movement in plasma torches. The work done at the author’s laboratory on studying the fluctuations in arc voltage, arc current, acoustic emissions and optical emissions are also presented. These fluctuations are observed to be chaotic and interrelated. Real time monitoring and controlling the arc instabilities through chaos characterization parameters can greatly contribute to the understanding of electrode erosion as well as improvement of plasma torch lifetime.

  10. High density plasma gun generates plasmas at 190 kilometers per second

    Science.gov (United States)

    Espy, P. N.

    1971-01-01

    Gun has thin metal foil disc which positions or localizes gas to be ionized during electrical discharge cycle, overcoming major limiting factor in obtaining such plasmas. Expanding plasma front travels at 190 km/sec, compared to plasmas of 50 to 60 km/sec previously achieved.

  11. The calculation of satellite line structures in highly stripped plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Abdallah, J. Jr.; Kilcrease, D.P. [Los Alamos National Lab., NM (United States); Faenov, A.Ya.; Pikuz, T.A. [Multicharged Ion Spectra Data Center, Moscow (Russian Federation)

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Recently developed high-resolution x-ray spectrographs have made it possible to measure satellite structures from various plasma sources with great detail. These lines are weak optically thin lines caused by the decay of dielectronic states and generally accompany the resonance lines of H-like and He-like ions. The Los Alamos atomic physics and kinetics codes provide a unique capability for calculating the position and intensities of such lines. These programs have been used to interpret such highly resolved spectral measurements from pulsed power devices and laser produced plasmas. Some of these experiments were performed at the LANL Bright Source and Trident laser facilities. The satellite structures are compared with calculations to diagnose temperatures and densities. The effect of non-thermal electron distributions of electrons on calculated spectra was also considered. Collaborations with Russian scientists have added tremendous value to this research die to their vast experience in x-ray spectroscopy.

  12. Changes of rat plasma total low molecular weight antioxidant level after tabun exposure and consequent treatment by acetylcholinesterase reactivators.

    Science.gov (United States)

    Pohanka, Miroslav; Karasova, Jana Zdarova; Musilek, Kamil; Kuca, Kamil; Jung, Young-Sik; Kassa, Jiri

    2011-02-01

    These experiments were performed on a rat model. The rats were divided into eight groups and consequently exposed to either a saline solution (control), atropine or a combination of atropine and tabun. The reactivation efficacy of the oximes was estimated on the rats exposed to tabun, atropine and a reactivator of AChE. The oximes HI-6, obidoxime, trimedoxime, K203 and KR-22836 were used as representative compounds of commonly available and new AChE reactivators. Besides the positive effect of the administered reactivators on blood AChE activity, the sizable modulation of low molecular weight antioxidant (LMWA) levels was also determined. The LMWA levels in the the animals treated with the oxime reactivators were decreased in comparison with the animals treated by atropine alone. It was found that the levels of LMWA returned to the level found in the control animals when either trimedoxime, K203 or KR-22836 were administered. The principle of oxime reactivator function and a novel insight into AChE activity regulation and oxidative stress is discussed.

  13. Reactive Processing and Co-Extrusion of Ultra-High Temperature Ceramics and Composites

    Science.gov (United States)

    2006-02-28

    F materials. Green billets were prepared by cold isostatic pressing at 300 MPa. The green billets were then loaded into BN-coated graphite dies for...reactively formed ZrB2 in ZrB2-SiC batches had a mean particle size of -0 nm and a residual non-uniform strain compressive strain of-0.21% at the...studies. Initial studies used cylindrical pellets that were 10 mm in diameter and 3 mm high were formed by isostatic pressing at 300 MPa. For the

  14. High-sensitivity C-reactive protein in paediatric inflammatory bowel disease

    Institute of Scientific and Technical Information of China (English)

    Marianne; Sidoroff; Riitta; Karikoski; Taneli; Raivio; Erkki; Savilahti; Kaija-Leena; Kolho

    2010-01-01

    AIM:To study whether high-sensitivity C-reactive protein(hs-CRP) measurement can aid the assessment of disease activity and glucocorticoid treatment in paediatric inflammatory bowel disease(IBD).METHODS:CRP levels were measured in 39 children with IBD undergoing colonoscopy [median age 12.8 years,Crohn's disease(CD) n=20],in 22 other children with IBD followed for acute response to glucocorticoids,and in 33 paediatric non-IBD patients.When standard CRP level was below detection limit(<5mg/L),hs-CRP was anal...

  15. Densification behavior of high Nb containing TiAl alloys through reactive hot pressing

    Institute of Scientific and Technical Information of China (English)

    Yanhang Wang; Junpin Lin; Yuehui He; Yanli Wang; Guoliang Chen

    2007-01-01

    Densification behavior of high Nb containing TiAl alloys through reactive hot pressing was investigated. The results showed that the density of the sample hot pressed at 1400℃ could reach a near full density of 98.37%. However, the densification abnormality was observed at 1500℃. The diffusion of elemental Nb during microstructural evolution is an important aspect affecting densification,which will form pore nests. With the increase of hot pressing temperature, the diffusion of Nb becomes more adequate. HIP (Hot isostatic pressing) treatment can only decrease porosity to some extent, but cannot eliminate it completely.

  16. High-gradient plasma-wakefield acceleration with two subpicosecond electron bunches.

    Science.gov (United States)

    Kallos, Efthymios; Katsouleas, Tom; Kimura, Wayne D; Kusche, Karl; Muggli, Patric; Pavlishin, Igor; Pogorelsky, Igor; Stolyarov, Daniil; Yakimenko, Vitaly

    2008-02-22

    A plasma-wakefield experiment is presented where two 60 MeV subpicosecond electron bunches are sent into a plasma produced by a capillary discharge. Both bunches are shorter than the plasma wavelength, and the phase of the second bunch relative to the plasma wave is adjusted by tuning the plasma density. It is shown that the second bunch experiences a 150 MeV/m loaded accelerating gradient in the wakefield driven by the first bunch. This is the first experiment to directly demonstrate high-gradient, controlled acceleration of a short-pulse trailing electron bunch in a high-density plasma.

  17. Role of plasma C-reactive protein and white blood cell count in predicting in-hospital clinical events of acute type A aortic dissection

    Institute of Scientific and Technical Information of China (English)

    WEN Dan; WU Hai-ying; JIANG Xiong-jing; ZHANG Hui-min; ZHOU Xian-liang; LI Jian-jun; HUI Ru-tai

    2011-01-01

    Background A few recent studies have reported that inflammation is associated with the prognosis of acute aortic dissection (AD).There is,however,no systemic investigation regarding the role of plasma C-reactive protein (CRP) and white blood cell (WBC) levels in predicting in-hospital clinical events of acute type AAD.Methods The levels of high-sensitivity CRP and WBC counts were systemically determined after admission in 36 patients with acute type A AD.The variations of plasma CRP and WBC levels in different time windows (admission,1,2,3,4,6,8 days) in patients with acute type A AD were analyzed between patients with events and without events.Results During hospitalization,five patients died,and increased levels of CRP and WBC were found in patients died with acute type A AD compared with patients survived (P <0.01,respectively).Medical treatment may significantly decrease inflammatory response in survived patients with acute type A AD.Additionally,patients with complication of pleural effusion showed higher CRP and WBC levels (P=0.046,P=0.018,respectively).Lower WBC levels were found in survived patients treated medically (P=0.001).Moreover,mean CRP and WBC levels had positive correlations with aortic diameter (r=0.364,P=0.000;r=0.333,P=0.000,respectively) and age (r=0.270,P=0.000,respectively),while negative correlations with the time from onset of symptoms to hospital admission (r=-0.229,P=0.000,r=-0.200,P=0.002,respectively).Univariate analysis showed that age ≥65 years,CRP ≥12.05 mg/L,WBC ≥12.16×109/L,aortic diameter ≥48mm,pleural effusion and diastolic blood pressure ≥105 mmHg were associated with hospital mortality.While CRP ≥12.05 mg/L,WBC ≥12.16×109/L,aortic diameter ≥48 mm were strongly associated with hospital mortality in multiple Logistic regression analysis.Conclusions The results suggested that CRP and WBC were preferred markers for predicting the clinical events in patients with acute type A AD,especially death during

  18. Runaway electron dynamics in tokamak plasmas with high impurity content

    Science.gov (United States)

    Martín-Solís, J. R.; Loarte, A.; Lehnen, M.

    2015-09-01

    The dynamics of high energy runaway electrons is analyzed for plasmas with high impurity content. It is shown that modified collision terms are required in order to account for the collisions of the relativistic runaway electrons with partially stripped impurity ions, including the effect of the collisions with free and bound electrons, as well as the scattering by the full nuclear and the electron-shielded ion charge. The effect of the impurities on the avalanche runaway growth rate is discussed. The results are applied, for illustration, to the interpretation of the runaway electron behavior during disruptions, where large amounts of impurities are expected, particularly during disruption mitigation by massive gas injection. The consequences for the electron synchrotron radiation losses and the resulting runaway electron dynamics are also analyzed.

  19. Assessment of Plasma Transport and Convection at High Latitudes

    Science.gov (United States)

    1984-01-01

    The high-latitude ionosphere is strongly coupled to the thermosphere and magnetosphere. The magnetospheric coupling occurs via electric fields, field-aligned currents, and particle precipitation. Owing to the interaction of the shocked solar wind with the geomagnetic field, an electric potential difference is generated across the tail of the magnetosphere, with the resulting electric field pointing from dawn to dusk. Energetic particle precipitation from the magnetosphere in the auroral region leads to the creation of ionization and to electron, ion, and neutral gas heating. In order to assess the current understanding of plasma transport and convection at high latitudes, it is necessary to take account of the strong coupling between the ionosphere, thermosphere, and magnetosphere.

  20. High-order harmonic generation in laser plasma plumes

    CERN Document Server

    Ganeev, Rashid A

    2013-01-01

    This book represents the first comprehensive treatment of high-order harmonic generation in laser-produced plumes, covering the principles, past and present experimental status and important applications. It shows how this method of frequency conversion of laser radiation towards the extreme ultraviolet range matured over the course of multiple studies and demonstrated new approaches in the generation of strong coherent short-wavelength radiation for various applications. Significant discoveries and pioneering contributions of researchers in this field carried out in various laser scientific centers worldwide are included in this first attempt to describe the important findings in this area of nonlinear spectroscopy. "High-Order Harmonic Generation in Laser Plasma Plumes" is a self-contained and unified review of the most recent achievements in the field, such as the application of clusters (fullerenes, nanoparticles, nanotubes) for efficient harmonic generation of ultrashort laser pulses in cluster-containin...

  1. The Turbulent Dynamo in Highly Compressible Supersonic Plasmas

    CERN Document Server

    Federrath, Christoph; Bovino, Stefano; Schleicher, Dominik R G

    2014-01-01

    The turbulent dynamo may explain the origin of cosmic magnetism. While the exponential amplification of magnetic fields has been studied for incompressible gases, little is known about dynamo action in highly-compressible, supersonic plasmas, such as the interstellar medium of galaxies and the early Universe. Here we perform the first quantitative comparison of theoretical models of the dynamo growth rate and saturation level with three-dimensional magnetohydrodynamical simulations of supersonic turbulence with grid resolutions of up to 1024^3 cells. We obtain numerical convergence and find that dynamo action occurs for both low and high magnetic Prandtl numbers Pm = nu/eta = 0.1-10 (the ratio of viscous to magnetic dissipation), which had so far only been seen for Pm >= 1 in supersonic turbulence. We measure the critical magnetic Reynolds number, Rm_crit = 129 (+43, -31), showing that the compressible dynamo is almost as efficient as in incompressible gas. Considering the physical conditions of the present a...

  2. Respiratory allergies and skin test reactivity in high school students in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    García-Ramos Alonso, E; Fernández-Caldas, E; Seleznick, M J; Lockey, R F

    1992-01-01

    The prevalence of skin test reactivity to 22 aeroallergens and of allergic respiratory diseases was determined in 501 high school students on the island of Tenerife, Spain. Two hundred seventy-seven students (55.2%) had at least one positive prick skin test (wheal > or = 2 mm). Two hundred sixteen students (43.1%) had symptoms of upper or lower respiratory tract allergies [24 (4.7%) had asthma with or without rhinitis and 192 (38.3%) seasonal or perennial rhinitis alone]. Two hundred eighty-five students (56.8%) were asymptomatic. One hundred per cent of the students with asthma, 87.5% of the students with rhinitis and 27.7% of the asymptomatic students had at least one positive skin test. The prevalence of positive skin tests was significantly higher in symptomatic than in asymptomatic students (p = 0.0001). One hundred seventy students (33.9%) had a family history of respiratory allergic diseases. The prevalence of positive skin tests among these students was significantly higher than in students without such history (p = 0.0001). Thus, there is a high prevalence of allergic respiratory diseases and skin test reactivity to aeroallergens among high school students in Tenerife. Significant correlations were found between family history, positive skin tests and respiratory allergic symptoms.

  3. Statistical model for combustion of high-metal magnesium-based hydro-reactive fuel

    Institute of Scientific and Technical Information of China (English)

    Hu Jian-Xin; Han Chao; Xia Zhi-Xun; Huang Li-Ya; Huang Xu

    2012-01-01

    We investigate experimentally and analytically the combustion behavior of a high-metal magnesium-based hydro-reactive fuel under high temperature gaseous atmosphere.The fuel studied in this paper contains 73% magnesium powders.An experimental system is designed and experimeuts are carried out in both argon and water vapor atmospheres.It is found that the burning surface temperature of the fuel is higher in water vapor than that in argon and both of them are higher than the melting point of magnesium,which indicates the molten state of magnesium particles in the burning surface of the fuel.Based on physical considerations and experimental results,a mathematical one-dimensional model is formulated to describe the combustion behavior of the high-metal magnesium-based hydro-reactive fuel.The model enables the evaluation of the burning surface temperature,the burning rate and the flame standoff distance each as a function of chamber pressure and water vapor concentration.The results predicted by the model show that the burning rate and the surface temperature increase when the chamber pressure and the water vapor concentration increase,which are in agreement with the observed experimental trends.

  4. Modelling deuterium release from tungsten after high flux high temperature deuterium plasma exposure

    Science.gov (United States)

    Grigorev, Petr; Matveev, Dmitry; Bakaeva, Anastasiia; Terentyev, Dmitry; Zhurkin, Evgeny E.; Van Oost, Guido; Noterdaeme, Jean-Marie

    2016-12-01

    Tungsten is a primary candidate for plasma facing materials for future fusion devices. An important safety concern in the design of plasma facing components is the retention of hydrogen isotopes. Available experimental data is vast and scattered, and a consistent physical model of retention of hydrogen isotopes in tungsten is still missing. In this work we propose a model of non-equilibrium hydrogen isotopes trapping under fusion relevant plasma exposure conditions. The model is coupled to a diffusion-trapping simulation tool and is used to interpret recent experiments involving high plasma flux exposures. From the computational analysis performed, it is concluded that high flux high temperature exposures (T = 1000 K, flux = 1024 D/m2/s and fluence of 1026 D/m2) result in generation of sub-surface damage and bulk diffusion, so that the retention is driven by both sub-surface plasma-induced defects (bubbles) and trapping at natural defects. On the basis of the non-equilibrium trapping model we have estimated the amount of H stored in the sub-surface region to be ∼10-5 at-1, while the bulk retention is about 4 × 10-7 at-1, calculated by assuming the sub-surface layer thickness of about 10 μm and adjusting the trap concentration to comply with the experimental results for the integral retention.

  5. Cerebrovascular reactivity among native-raised high altitude residents: an fMRI study

    Directory of Open Access Journals (Sweden)

    Zhang Jiaxing

    2011-09-01

    Full Text Available Abstract Background The impact of long term residence on high altitude (HA on human brain has raised concern among researchers in recent years. This study investigated the cerebrovascular reactivity among native-born high altitude (HA residents as compared to native sea level (SL residents. The two groups were matched on the ancestral line, ages, gender ratios, and education levels. A visual cue guided maximum inspiration task with brief breath holding was performed by all the subjects while Blood-Oxygenation-Level-Dependent (BOLD functional Magnetic Resonance Imaging (fMRI data were acquired from them. Results Compared to SL controls, the HA group showed generally decreased cerebrovascular reactivity and longer delay in hemodynamic response. Clusters showing significant differences in the former aspect were located at the bilateral primary motor cortex, the right somatosensory association cortex, the right thalamus and the right caudate, the bilateral precuneus, the right cingulate gyrus and the right posterior cingulate cortex, as well as the left fusiform gyrus and the right lingual cortex; clusters showing significant differences in the latter aspect were located at the precuneus, the insula, the superior frontal and temporal gyrus, the somatosensory cortex (the postcentral gyrus and the cerebellar tonsil. Inspiratory reserve volume (IRV, which is an important aspect of pulmonary function, demonstrated significant correlation with the amount of BOLD signal change in multiple brain regions, particularly at the bilateral insula among the HA group. Conclusions Native-born HA residents generally showed reduced cerebrovascular reactivity as demonstrated in the hemodynamic response during a visual cue guided maximum inspiration task conducted with BOLD-fMRI. This effect was particularly manifested among brain regions that are typically involved in cerebral modulation of respiration.

  6. The emerging role of reactive oxygen and nitrogen species in redox biology and some implications for plasma applications to medicine and biology

    Science.gov (United States)

    Graves, David B.

    2012-07-01

    Reactive oxygen species (ROS) and the closely related reactive nitrogen species (RNS) are often generated in applications of atmospheric pressure plasmas intended for biomedical purposes. These species are also central players in what is sometimes referred to as ‘redox’ or oxidation-reduction biology. Oxidation-reduction biochemistry is fundamental to all of aerobic biology. ROS and RNS are perhaps best known as disease-associated agents, implicated in diabetes, cancer, heart and lung disease, autoimmune disease and a host of other maladies including ageing and various infectious diseases. These species are also known to play active roles in the immune systems of both animals and plants and are key signalling molecules, among many other important roles. Indeed, the latest research has shown that ROS/RNS play a much more complex and nuanced role in health and ageing than previously thought. Some of the most potentially profound therapeutic roles played by ROS and RNS in various medical interventions have emerged only in the last several years. Recent research suggests that ROS/RNS are significant and perhaps even central actors in the actions of antimicrobial and anti-parasite drugs, cancer therapies, wound healing therapies and therapies involving the cardiovascular system. Understanding the ways ROS/RNS act in established therapies may help guide future efforts in exploiting novel plasma medical therapies. The importance of ROS and RNS to plant biology has been relatively little appreciated in the plasma biomedicine community, but these species are just as important in plants. It appears that there are opportunities for useful applications of plasmas in this area as well.

  7. Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein.

    Directory of Open Access Journals (Sweden)

    Sheng Li Hu

    Full Text Available Hypersensitive C-reaction protein (hsCRP may be a risk factor for cognitive impairment resulting from Alzheimer's disease (AD, stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200 detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6, and homocysteine was estimated at 500 m altitude, 3650 m altitude, 3 day, 1, and 3 month post arriving at the base camp (4400 m, and 1 month after coming back to the 500 m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400 m. P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction.

  8. Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein

    Science.gov (United States)

    Hu, Sheng Li; Xiong, Wei; Dai, Zhi Qiang; Zhao, Heng Li; Feng, Hua

    2016-01-01

    Hypersensitive C-reaction protein (hsCRP) may be a risk factor for cognitive impairment resulting from Alzheimer’s disease (AD), stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200) detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6), and homocysteine was estimated at 500m altitude, 3650m altitude, 3day, 1, and 3 month post arriving at the base camp (4400m), and 1 month after coming back to the 500m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400m). P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction. PMID:26731740

  9. Chromium(VI)-induced Production of Reactive Oxygen Species, Change of Plasma Membrane Potential and Dissipation of Mitochondria Membrane Potential in Chinese Hamster Lung Cell Cultures

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To examine whether Reactive Oxygen Species (ROS) is generated, and whether plasma membrane potential and mitochondrial membrane potential are depolarized in Chinese Hamster Lung (CHL) cell lines exposed to Cr (VI). Methods CHL cells were incubated with Cr(VI) at 10 μmol/L, 2.5 μmol/L, 0.65 μmol/L for 3 and 6 hours, respectively. The production of ROS was performed by using 2,7_dichlorofluorescin diacetate; The changes in plasma membrane potential were estimated using fluorescent cationic dye DiBAC4; And the changes in mitochondria membrane potential were estimated using fluorescent dye Rhodamine 123. Results The ROS levels in CHL cells increased in all treated groups compared with the control group (P<0.01); The plasma membrane potential and mitochondrial membrane potential in CHL cells dissipated after incubated with Cr(VI) at 10 μmol/L for 3 hours and 6 hours (P<0.01), at 2.5 μmol/L for 6 hours (P<0.01 or 0.05). Conclusion Cr(VI) causes the dissipation of plasma membrane potential and mitochondrial membrane potential in CHL cell cultures, and Cr(VI)_induced ROS may play a role in the injuries.

  10. Plasma wakefield excitation by incoherent laser pulses: a path towards high-average power laser-plasma accelerators

    CERN Document Server

    Benedetti, C; Esarey, E; Leemans, W P

    2014-01-01

    In a laser plasma accelerator (LPA), a short and intense laser pulse propagating in a plasma drives a wakefield (a plasma wave with a relativistic phase velocity) that can sustain extremely large electric fields, enabling compact accelerating structures. Potential LPA applications include compact radiation sources and high energy linear colliders. We propose and study plasma wave excitation by an incoherent combination of a large number of low energy laser pulses (i.e., without constraining the pulse phases). We show that, in spite of the incoherent nature of electromagnetic fields within the volume occupied by the pulses, the excited wakefield is regular and its amplitude is comparable or equal to that obtained using a single, coherent pulse with the same energy. These results provide a path to the next generation of LPA-based applications, where incoherently combined multiple pulses may enable high repetition rate, high average power LPAs.

  11. Affective and neural reactivity to criticism in individuals high and low on perceived criticism.

    Science.gov (United States)

    Hooley, Jill M; Siegle, Greg; Gruber, Staci A

    2012-01-01

    People who have remitted from depression are at increased risk for relapse if they rate their relatives as being critical of them on a simple self-report measure of Perceived Criticism (PC). To explore neural mechanisms associated with this we used functional magnetic resonance imaging (fMRI) to examine how people with different levels of PC responded to hearing criticism from their own mothers. To maximize variability in affective reactivity, depressed, recovered depressed, and healthy control participants (n = 33) were classified as high or low in PC based on a median split. They were then exposed to personally-relevant critical and praising comments from their mothers. Perceived Criticism levels were unrelated to depression status and to negative mood change after hearing criticism. However, compared to low PC participants, those who scored high on PC showed differential activation in a network of regions associated with emotion reactivity and regulation, including increased amygdala activity and decreased reactions in prefrontal regulatory regions when they heard criticism. This was not the case for praise. Criticism may be a risk factor for relapse because it helps to "train" pathways characteristic of depressive information processing. The Perceived Criticism measure may help identify people who are more susceptible to this vulnerability.

  12. High sensitive and high temporal and spatial resolved image of reactive species in atmospheric pressure surface discharge reactor by laser induced fluorescence

    Science.gov (United States)

    Gao, Liang; Feng, Chun-Lei; Wang, Zhi-Wei; Ding, Hongbin

    2017-05-01

    The current paucity of spatial and temporal characterization of reactive oxygen and nitrogen species (RONS) concentration has been a major hurdle to the advancement and clinical translation of low temperature atmospheric plasmas. In this study, an advanced laser induced fluorescence (LIF) system has been developed to be an effective antibacterial surface discharge reactor for the diagnosis of RONS, where the highest spatial and temporal resolution of the LIF system has been achieved to ˜100 μm scale and ˜20 ns scale, respectively. Measurements on an oxidative OH radical have been carried out as typical RONS for the benchmark of the whole LIF system, where absolute number density calibration has been performed on the basis of the laser Rayleigh scattering method. Requirements for pixel resolved spatial distribution and outer plasma region detection become challenging tasks due to the low RONS concentration (˜ppb level) and strong interference, especially the discharge induced emission and pulsed laser induced stray light. In order to design the highly sensitive LIF system, a self-developed fluorescence telescope, the optimization of high precision synchronization among a tunable pulsed laser, a surface discharge generator, intensified Charge Coupled Device (iCCD) camera, and an oscilloscope have been performed. Moreover, an image BOXCAR approach has been developed to remarkably improve the sensitivity of the whole LIF system by optimizing spatial and temporal gating functions via both hardware and software, which has been integrated into our automatic control and data acquisition system on the LabVIEW platform. In addition, a reciprocation averaging measurement has been applied to verify the accuracy of the whole LIF detecting system, indicating the relative standard deviation of ˜3%.

  13. Traces of isotopic reactive species produced from a non-thermal plasma jet in bio-molecules

    Science.gov (United States)

    Lee, C. B.; Kwak, H. S.; Choi, E. H.; Hong, T. E.; Yoon, H.; Lee, Y.; Baik, K. Y.; Uhm, H. S.

    2015-11-01

    Heavy water (D2O) is introduced into a non-thermal plasma jet (NTPJ) device to generate deuterium monoxide (OD) radicals instead of hydroxyl (OH) radicals. An NTPJ generated from a vapor mixture of N2/H2O and N2/D2O is applied to a cell membrane component and its effects are analyzed by means of 1H NMR, GC-FID and TOF-SIMS spectroscopies. The results show that OH and OD radical species induce similar levels of oxidative breakage of lipid molecules. In addition, the 2H NMR spectra show that deuteriums are incorporated into the lipid oxidative products. In order to trace these effects in vivo, E. coli bacteria are treated with an NTPJ and analyzed using NanoSIMS. Deuterium is observed in both the cytoplasm and membrane, which are colocalized well with nitrogen and phosphorus atoms. The high colocalization of D atoms inside E. coli provides the first direct and visual evidence of the role of OD radicals, which may be utilized to visualize OH radical interactions inside cells.

  14. A study of the oxygen dynamics in a reactive Ar/O2 high power impulse magnetron sputtering discharge using an ionization region model

    Science.gov (United States)

    Lundin, D.; Gudmundsson, J. T.; Brenning, N.; Raadu, M. A.; Minea, T. M.

    2017-05-01

    The oxygen dynamics in a reactive Ar/O2 high power impulse magnetron sputtering discharge has been studied using a new reactive ionization region model. The aim has been to identify the dominating physical and chemical reactions in the plasma and on the surfaces of the reactor affecting the oxygen plasma chemistry. We explore the temporal evolution of the density of the ground state oxygen molecule O 2 ( X 1 Σg - ) , the singlet metastable oxygen molecules O 2 ( a 1 Δ g ) and O 2 ( b 1 Σ g ) , the oxygen atom in the ground state O(3P), the metastable oxygen atom O(1D), the positive ions O2 + and O+, and the negative ion O-. We furthermore investigate the reaction rates for the gain and loss of these species. The density of atomic oxygen increases significantly as we move from the metal mode to the transition mode, and finally into the compound (poisoned) mode. The main gain rate responsible for the increase is sputtering of atomic oxygen from the oxidized target. Both in the poisoned mode and in the transition mode, sputtering makes up more than 80% of the total gain rate for atomic oxygen. We also investigate the possibility of depositing stoichiometric TiO2 in the transition mode.

  15. Reactivity Accountability Attributed to Reflector Poisons in the High Flux Isotope Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, David [ORNL; Maldonado, G Ivan [ORNL; Primm, Trent [ORNL

    2009-12-01

    The objective of this study is to develop a methodology to predict the reactivity impact as a function of outage time between cycles of 3He, 6Li, and other poisons in the High Flux Isotope Reactor s (HFIR) beryllium reflector. The reactivity worth at startup of the HFIR has been incorrectly predicted in the past after the reactor has been shut-down for long periods of time. The incorrect prediction was postulated to be due to the erroneous calculation of 3He buildup in the beryllium reflector. It is necessary to develop a better estimate of the start-of-cycle symmetric critical control element positions since if the estimated and actual symmetrical critical control element positions differ by more than $1.55 in reactivity (approximately one-half inch in control element startup position), HFIR is to be shutdown and a technical evaluation is performed to resolve the discrepancy prior to restart. 3He is generated and depleted during operation, but during an outage, the depletion of 3He ceases because it is a stable isotope. 3He is born from the radioactive decay of tritium, and thus the concentration of 3He increases during shutdown. SCALE, specifically the TRITON and CSAS5 control modules including the KENO V.A, COUPLE, and ORIGEN functional modules were utilized in this study. An equation relating the down time (td) to the change in symmetric control element position was generated and validated against measurements for approximately 40 HFIR operating cycles. The newly-derived correlation was shown to improve accuracy of predictions for long periods of down time.

  16. High Power Light Gas Helicon Plasma Source for VASIMR

    Science.gov (United States)

    Squire, Jared P.; Chang-Diaz, Franklin R.; Glover, Timothy W.; Jacobson, Verlin T.; Baity, F. Wally; Carter, Mark D.; Goulding, Richard H.

    2004-01-01

    In the Advanced Space Propulsion Laboratory (ASPL) helicon experiment (VX-10) we have measured a plasma flux to input gas rate ratio near 100% for both helium and deuterium at power levels up to 10 kW. Recent results at Oak Ridge National Laboratory (ORNL) show enhanced efficiency operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 10 kW of input power. The data here uses a Boswell double-saddle antenna design with a magnetic cusp just upstream of the antenna. Similar to ORNL, for deuterium at near 10 kW, we find an enhanced performance of operation at magnetic fields above the lower hybrid matching condition.

  17. Viscous Kelvin-Helmholtz instabilities in highly ionised plasmas

    CERN Document Server

    Roediger, E; Nulsen, P; Churazov, E; Forman, W; Brueggen, M; Kokotanekova, R

    2013-01-01

    Transport coefficients in highly ionised plasmas like the intra-cluster medium (ICM) are still ill-constrained. They influence various processes, among them the mixing at shear flow interfaces due to the Kelvin-Helmholtz instability (KHI). The observed structure of potential mixing layers can be used to infer the transport coefficients, but the data interpretation requires a detailed knowledge of the long-term evolution of the KHI under different conditions. Here we present the first systematic numerical study of the effect of constant and temperature-dependent isotropic viscosity over the full range of possible values. We show that moderate viscosities slow down the growth of the KHI and reduce the height of the KHI rolls and their rolling-up. Viscosities above a critical value suppress the KHI. The effect can be quantified in terms of the Reynolds number Re = U{\\lambda}/{\

  18. High Power Light Gas Helicon Plasma Source for VASIMR

    Science.gov (United States)

    Squire, Jared P.; Chang-Diaz, Franklin R.; Glover, Timothy W.; Jacobson, Verlin T.; Baity, F. Wally; Carter, Mark D.; Goulding, Richard H.

    2004-01-01

    In the Advanced Space Propulsion Laboratory (ASPL) helicon experiment (VX-10) we have measured a plasma flux to input gas rate ratio near 100% for both helium and deuterium at power levels up to 10 kW. Recent results at Oak Ridge National Laboratory (ORNL) show enhanced efficiency operation with a high power density, over 5 kW in a 5 cm diameter tube. Our helicon is presently 9 cm in diameter and operates up to 10 kW of input power. The data here uses a Boswell double-saddle antenna design with a magnetic cusp just upstream of the antenna. Similar to ORNL, for deuterium at near 10 kW, we find an enhanced performance of operation at magnetic fields above the lower hybrid matching condition.

  19. CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Professor Bruce R. Kusse; Professor David A. Hammer

    2007-04-18

    This annual report summarizes the activities of the Cornell Center for Pulsed-Power-Driven High-Energy-Density Plasma Studies, for the 12-month period October 1, 2005-September 30, 2006. This period corresponds to the first year of the two-year extension (awarded in October, 2005) to the original 3-year NNSA/DOE Cooperative Agreement with Cornell, DE-FC03-02NA00057. As such, the period covered in this report also corresponds to the fourth year of the (now) 5-year term of the Cooperative Agreement. The participants, in addition to Cornell University, include Imperial College, London (IC), the University of Nevada, Reno (UNR), the University of Rochester (UR), the Weizmann Institute of Science (WSI), and the P.N. Lebedev Physical Institute (LPI), Moscow. A listing of all faculty, technical staff and students, both graduate and undergraduate, who participated in Center research activities during the year in question is given in Appendix A.

  20. Combustion and Plasma Synthesis of High-Temperature Materials

    Science.gov (United States)

    Munir, Z. A.; Holt, J. B.

    1997-04-01

    , et al.). Combustion Synthesis in the Ti-C-Ni-Al System (S. Dunmead, et al.). Combustion Synthesis Dynamics Modeling (T. Kottke, et al.). Elementary Processes in SiO2-Al Thermite-Type Reactions Activated or Induced by Mechanochemical Treatment (G. Hida & I. Lin). Combustion Synthesis of Ceramic Preforms for Molten-Metal Infiltration (D. Halverson, et al.). Combustion Characteristics of Solid-Solid Systems: Experiments and Modeling (S. Kumar, et al.). Microstructure of TiB2 Sintered by the Self-Combustion Method (K. Urabe, et al..). A Laser-Ignition Study of Gasless Reactions Using Thermography (C. Chow & J. Mohler). Shock-Induced Reaction Synthesis-Assisted Processing of Ceramics (R. Ward, et al.). Summary Assessment of the Application of SPS and Related Reaction Processing to Produce Dense Ceramics (R. Rice). Shock Consolidation of Combustion-Synthesized Ceramics (A. Niiler, et al.). High-Pressure Burning Rate of Silicon in Nitrogen (M. Costantino & J. Holt). Preparation of a TiC Single Crystal by the Floating-Zone Method from a Self-Combustion Rod (S. Otani, et al.). PLASMA AND GAS-PHASE SYNTHESIS. Thermal Plasma Synthesis of Ceramic Powders and Coatings (T. Yoshida). A Theoretical Comparison of Conventional and Hybrid RF-Plasma Reactors (J. McKelliget & N. El-Kaddah). Homogeneous Nucleation and Particle Growth in Thermal Plasma Synthesis (S. Girshick & C.-P. Chiu). Formation of Refractory Aerosol Particles (R. Flagan, et al.). Ceramic-Powder Synthesis in an Aerosol Reactor (M. Alam, et al.). Silica-Particle Formation Using the Counter-Flow Diffusion Flame Burner (J. Katz, et al.). Synthesis and Properties of Low-Carbon Boron Carbides (C. Adkins, et al.). Synthesis of Si, SiC, and Si3N4 Powders Under High Number Density Conditions (J. Haggerty & J. Flint). Rapid Preparation of Titanium and Other Transition-Metal Nitride- and Carbide Powders by a Carbo-Reduction Method Using Arc-Image Heating (M. Yoshimura, et al.). Microwave Plasma Densification of Aluminum Nitride

  1. The effect of quercetin on plasma oxidative status, C-reactive protein and blood pressure in women with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Fatemeh Javadi

    2014-01-01

    Conclusions: In this study, quercetin had no effect on oxidative and inflammatory status of plasma and blood pressure in patients with RA. Further studies are needed to ensure the effect of quercetin on oxidative stress and inflammation in human.

  2. Non-LTE Radiation Transport in High Radiation Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Scott, H A

    2005-01-07

    A primary goal of numerical radiation transport is obtaining a self-consistent solution for both the radiation field and plasma properties. Obtaining such a solution requires consideration of the coupling between the radiation and the plasma. The different characteristics of this coupling for continuum and line radiation have resulted in two separate sub-disciplines of radiation transport with distinct emphases and computational techniques. LTE radiation transfer focuses on energy transport and exchange through broadband radiation, primarily affecting temperature and ionization balance. Non-LTE line transfer focuses on narrowband radiation and the response of individual level populations, primarily affecting spectral properties. Many high energy density applications, particularly those with high-Z materials, incorporate characteristics of both these regimes. Applications with large radiation fields including strong line components require a non-LTE broadband treatment of energy transport and exchange. We discuss these issues and present a radiation transport treatment which combines features of both types of approaches by explicitly incorporating the dependence of material properties on both temperature and radiation fields. The additional terms generated by the radiation dependence do not change the character of the system of equations and can easily be added to a numerical transport implementation. A numerical example from a Z-pinch application demonstrates that this method improves both the stability and convergence of the calculations. The information needed to characterize the material response to radiation is closely related to that used by the Linear Response Matrix (LRM) approach to near-LTE simulation, and we investigate the use of the LRM for these calculations.

  3. Surface Reactivity in Tropical Highly Weathered Soils and Implications for Rational Soil Management

    Institute of Scientific and Technical Information of China (English)

    R. MOREAU; J. PETARD

    2004-01-01

    Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this paper.Factors controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.

  4. Ice sheets as a significant source of highly reactive nanoparticulate iron to the oceans.

    Science.gov (United States)

    Hawkings, Jon R; Wadham, Jemma L; Tranter, Martyn; Raiswell, Rob; Benning, Liane G; Statham, Peter J; Tedstone, Andrew; Nienow, Peter; Lee, Katherine; Telling, Jon

    2014-05-21

    The Greenland and Antarctic Ice Sheets cover ~ 10% of global land surface, but are rarely considered as active components of the global iron cycle. The ocean waters around both ice sheets harbour highly productive coastal ecosystems, many of which are iron limited. Measurements of iron concentrations in subglacial runoff from a large Greenland Ice Sheet catchment reveal the potential for globally significant export of labile iron fractions to the near-coastal euphotic zone. We estimate that the flux of bioavailable iron associated with glacial runoff is 0.40-2.54 Tg per year in Greenland and 0.06-0.17 Tg per year in Antarctica. Iron fluxes are dominated by a highly reactive and potentially bioavailable nanoparticulate suspended sediment fraction, similar to that identified in Antarctic icebergs. Estimates of labile iron fluxes in meltwater are comparable with aeolian dust fluxes to the oceans surrounding Greenland and Antarctica, and are similarly expected to increase in a warming climate with enhanced melting.

  5. Cardiovascular Reactivity in Patients With Major Depressive Disorder With High- or Low-Level Depressive Symptoms: A Cross-Sectional Comparison of Cardiovascular Reactivity to Laboratory-Induced Mental Stress.

    Science.gov (United States)

    Wang, Mei-Yeh; Chiu, Chen-Huan; Lee, Hsin-Chien; Su, Chien-Tien; Tsai, Pei-Shan

    2016-03-01

    Depression increases the risk of adverse cardiac events. Cardiovascular reactivity is defined as the pattern of cardiovascular responses to mental stress. An altered pattern of cardiovascular reactivity is an indicator of subsequent cardiovascular disease. Because depression and adverse cardiac events may have a dose-dependent association, this study examined the differences in cardiovascular reactivity to mental stress between patients with major depressive disorder (MDD) with high depression levels and those with low depression levels. Moreover, autonomic nervous system regulation is a highly plausible biological mechanism for the pattern of cardiovascular reactivity to mental stress. The association between cardiovascular reactivity and parameters of heart rate variability (HRV), an index for quantifying autonomic nervous system activity modulation, was thus examined. This study included 88 patients with MDD. HRV was measured before stress induction. The Stroop Color and Word Test and mirror star-tracing task were used to induce mental stress. We observed no significant association between depressive symptom level and any of the cardiovascular reactivity parameters. Cardiovascular reactivity to mental stress was comparable between patients with MDD with high-level depressive symptoms and those with low-level depressive symptoms. After adjusting for confounding variables, the high-frequency domain of HRV was found to be an independent predictor of the magnitude of heart rate reactivity (β = -.33, p = .002). In conclusion, the magnitude of cardiovascular reactivity may be independent of depression severity in patients with MDD. The autonomic regulation of cardiovascular responses to mental stress primarily influences heart rate reactivity in patients with MDD.

  6. Effects of irradiation distance on supply of reactive oxygen species to the bottom of a Petri dish filled with liquid by an atmospheric O{sub 2}/He plasma jet

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Toshiyuki, E-mail: kawasaki@nbu.ac.jp; Kusumegi, Shota; Kudo, Akihiro; Sakanoshita, Tomohiro; Tsurumaru, Takuya; Sato, Akihiro [Department of Mechanical and Electrical Engineering, Nippon Bunri University, Oita, Oita 870-0397 (Japan); Uchida, Giichiro [Joining and Welding Research Institute, Osaka University, Ibaraki, Osaka 567-0047 (Japan); Koga, Kazunori; Shiratani, Masaharu [Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka, Fukuoka 819-0395 (Japan)

    2016-05-07

    The impact of irradiation distances on plasma jet-induced specific effects on the supply of reactive oxygen species (ROS) to the bottom of a Petri dish filled with liquid was investigated using a KI-starch gel reagent that can be employed as a ROS indicator even in water. O{sub 3} exposure experiments without plasma irradiation were also performed to elucidate the specific effects of the plasma jet. Relative concentrations of ROS transported to the bottom were evaluated using absorbance measurements. The results indicated that ROS supply to the bottom is markedly enhanced by the plasma jet irradiation at shorter irradiation distances, whereas similar results could not be obtained for the O{sub 3} exposure. In these cases, the liquid mixing in the depth direction was also enhanced by the plasma jet irradiation only, and the supply of reactive atomic oxygen to the liquid surface was markedly increased as well.

  7. Enhancing gas-phase reaction in a plasma using high intensity and high power ultrasonic acoustic waves

    DEFF Research Database (Denmark)

    2010-01-01

    is absorbed into said plasma (104), and where a sound pressure level of said generated ultrasonic high intensity and high power acoustic waves (102) is at least substantially 140 dB and where an acoustic power of said generated ultrasonic high intensity and high power acoustic waves (102); is at least......This invention relates to enhancing a gas-phase reaction in a plasma comprising: creating plasma (104) by at least one plasma source (106), and wherein that the method further comprises: generating ultrasonic high intensity and high power acoustic waves (102) having a predetermined amount...... of acoustic energy by at least one ultrasonic high intensity and high power gas-jet acoustic wave generator (101), where said ultrasonic high intensity and high power acoustic waves are directed to propagate towards said plasma (104) so that at least a part of said predetermined amount of acoustic energy...

  8. Moderate alcohol consumption reduces plasma C-reactive protein and fibrinogen levels : a randomized, diet-controlled intervention study

    NARCIS (Netherlands)

    Sierksma, A.; Gaag, M.S. van der; Kluft, C.; Hendriks, H.F.J.

    2002-01-01

    Objective: To evaluate the effect of moderate alcohol consumption on the acute phase proteins C-reactive protein and fibrinogen. Design: Randomized, diet-controlled, cross-over study. Setting: The study was performed at TNO Nutrition and Food Research, Zeist, The Netherlands. Subjects: Ten middle-ag

  9. Association of high-sensitive C-reactive protein and dialysis adequacy with uremic pruritus.

    Science.gov (United States)

    Malekmakan, Leila; Malekmakan, Alireza; Sayadi, Mehrab; Pakfetrat, Maryam; Sepaskhah, Mozhdeh; Roozbeh, Jamshid

    2015-09-01

    Uremic pruritus is a difficult symptom in chronic hemodialysis (HD) patients, and its patho-physiological mechanism remains unknown. To determine the relationship between pruritus and C-reactive protein as well as dialysis adequacy among the HD patients, we studied 241 chronic HD patients in Shiraz dialysis centers, Iran. The patients were selected by convenient sampling and the data were collected using a checklist, interview and lab tests. The mean age of our patients was 53.9 ± 16.3 years and 128 (53.1%) of them were male. There were 97 (40.2%) patients who complained of pruritus. A significant association was found between high-sensitive C-reactive protein and pruritus (P = 0.004). Also, a significant positive relationship was observed between pruritus and dialysis adequacy (P dialysis adequacy and pruritus. A better understanding of the factors implicated in the cause of uremic pruritus is essential in the development of more-effective treatments and improved quality of life in HD patients.

  10. Highly sensitive SnO2 sensor via reactive laser-induced transfer

    Science.gov (United States)

    Palla Papavlu, Alexandra; Mattle, Thomas; Temmel, Sandra; Lehmann, Ulrike; Hintennach, Andreas; Grisel, Alain; Wokaun, Alexander; Lippert, Thomas

    2016-04-01

    Gas sensors based on tin oxide (SnO2) and palladium doped SnO2 (Pd:SnO2) active materials are fabricated by a laser printing method, i.e. reactive laser-induced forward transfer (rLIFT). Thin films from tin based metal-complex precursors are prepared by spin coating and then laser transferred with high resolution onto sensor structures. The devices fabricated by rLIFT exhibit low ppm sensitivity towards ethanol and methane as well as good stability with respect to air, moisture, and time. Promising results are obtained by applying rLIFT to transfer metal-complex precursors onto uncoated commercial gas sensors. We could show that rLIFT onto commercial sensors is possible if the sensor structures are reinforced prior to printing. The rLIFT fabricated sensors show up to 4 times higher sensitivities then the commercial sensors (with inkjet printed SnO2). In addition, the selectivity towards CH4 of the Pd:SnO2 sensors is significantly enhanced compared to the pure SnO2 sensors. Our results indicate that the reactive laser transfer technique applied here represents an important technical step for the realization of improved gas detection systems with wide-ranging applications in environmental and health monitoring control.

  11. A STUDY OF HIGH SENSITIVITY C-REACTIVE PROTEIN IN UNSTABLE ANGINA

    Directory of Open Access Journals (Sweden)

    Satish

    2014-11-01

    Full Text Available BACKGROUND: Unstable angina has a wide variability in its natural history, changing concepts of Pathophysiology, and newer approaches to its management strategies. So, unstable angina still has importance and prime interest in research work. Various ongoing research works has provided newer insights in pathophysiology of unstable angina syndrome and helps in recognition of clinical variability and unpredictability of it. C - reactive protein being the most sensitive acute phase reactant currently held. A recent previous study has estimated the levels and values of high-sensitivity C - reactive protein in both stable and unstable angina pectoris. Data provided by the study indicated need for further studies in this field. With all these facts, the present study is carried out to estimated Hs CRP levels as a marker of inflammation in patient of unstable angina. AIMS AND OBJECTIVES: The present study was carried out with the following Aims and Objectives. To estimate Hs-CRP levels as a marker of inflammation in patients of unstable angina. To compare Hs-CRP levels in cases of unstable angina, with Hs-CRP levels in patients of stable angina and in healthy age and sex matched controls. MATERIAL AND METHODS: This study was carried out at Basaveshwar Teaching and General Hospital, Gulbarga, MRMC Gulbarga. Approximate duration of study was 1 ½ year from June-2008 to November, 2010. OBSERVATION: Following are the conclusions drawn from the present study.

  12. Suppressed ion-scale turbulence in a hot highplasma

    Science.gov (United States)

    Schmitz, L.; Fulton, D. P.; Ruskov, E.; Lau, C.; Deng, B. H.; Tajima, T.; Binderbauer, M. W.; Holod, I.; Lin, Z.; Gota, H.; Tuszewski, M.; Dettrick, S. A.; Steinhauer, L. C.

    2016-12-01

    An economic magnetic fusion reactor favours a high ratio of plasma kinetic pressure to magnetic pressure in a well-confined, hot plasma with low thermal losses across the confining magnetic field. Field-reversed configuration (FRC) plasmas are potentially attractive as a reactor concept, achieving high plasma pressure in a simple axisymmetric geometry. Here, we show that FRC plasmas have unique, beneficial microstability properties that differ from typical regimes in toroidal confinement devices. Ion-scale fluctuations are found to be absent or strongly suppressed in the plasma core, mainly due to the large FRC ion orbits, resulting in near-classical thermal ion confinement. In the surrounding boundary layer plasma, ion- and electron-scale turbulence is observed once a critical pressure gradient is exceeded. The critical gradient increases in the presence of sheared plasma flow induced via electrostatic biasing, opening the prospect of active boundary and transport control in view of reactor requirements.

  13. Residual gas entering high density hydrogen plasma: rarefaction due to rapid heating

    NARCIS (Netherlands)

    N. den Harder,; D.C. Schram,; W. J. Goedheer,; de Blank, H. J.; M. C. M. van de Sanden,; van Rooij, G. J.

    2015-01-01

    The interaction of background molecular hydrogen with magnetized (0.4 T) high density (1–5 × 10 20  m −3 ) low temperature (∼3 eV) hydrogen plasma was inferred from the Fulcher band emission in the linear plasma generator Pilot-PSI. In the plasma center,

  14. High heat flux capabilities of the Magnum-PSI linear plasma device

    Energy Technology Data Exchange (ETDEWEB)

    De Temmerman, G., E-mail: g.c.detemmerman@differ.nl; Berg, M.A. van den; Scholten, J.; Lof, A.; Meiden, H.J. van der; Eck, H.J.N. van; Morgan, T.W.; Kruijf, T.M. de; Zeijlmans van Emmichoven, P.A.; Zielinski, J.J.

    2013-10-15

    Magnum-PSI is an advanced linear plasma device uniquely capable of producing plasma conditions similar to those expected in the divertor of ITER both steady-state and transients. The machine is designed both for fundamental studies of plasma–surface interactions under high heat and particle fluxes, and as a high-heat flux facility for the tests of plasma-facing components under realistic plasma conditions. To study the effects of transient heat loads on a plasma-facing surface, a novel pulsed plasma source system as well as a high power laser is available. In this article, we will describe the capabilities of Magnum-PSI for high-heat flux tests of plasma-facing materials.

  15. Dynamic properties of ionospheric plasma turbulence driven by high-power high-frequency radiowaves

    Science.gov (United States)

    Grach, S. M.; Sergeev, E. N.; Mishin, E. V.; Shindin, A. V.

    2017-02-01

    A review is given of the current state-of-the-art of experimental studies and the theoretical understanding of nonlinear phenomena that occur in the ionospheric F-layer irradiated by high-power high-frequency ground-based transmitters. The main focus is on the dynamic features of high-frequency turbulence (plasma waves) and low-frequency turbulence (density irregularities of various scales) that have been studied in experiments at the Sura and HAARP heating facilities operated in temporal and frequency regimes specially designed with consideration of the characteristic properties of nonlinear processes in the perturbed ionosphere using modern radio receivers and optical instruments. Experimental results are compared with theoretical turbulence models for a magnetized collisional plasma in a high-frequency electromagnetic field, allowing the identification of the processes responsible for the observed features of artificial ionospheric turbulence.

  16. Thermochemical process for seasonal storage of solar energy: characterization and modeling of a high-density reactive bed

    OpenAIRE

    Michel, Benoit; Mazet, Nathalie; Mauran, Sylvain; Stitou, Driss; Jing XU

    2012-01-01

    International audience; This paper focuses on the characterization and modeling of a solid/gas thermochemical reaction between a porous reactive bed and moist air flowing through it. The aim is the optimization of both energy density and permeability of the reactive bed, in order to realize a high density thermochemical system for seasonal thermal storage for house heating application. Several samples with different implementation parameters (density, binder, diffuser, porous bed texture) hav...

  17. Advances in the MQDT approach of electron/molecular cation reactive collisions: High precision extensive calculations for applications

    Directory of Open Access Journals (Sweden)

    Motapon O.

    2015-01-01

    Full Text Available Recent advances in the stepwise multichannel quantum defect theory approach of electron/molecular cation reactive collisions have been applied to perform computations of cross sections and rate coefficients for dissociative recombination and electron-impact ro-vibrational transitions of H2+, BeH+ and their deuterated isotopomers. At very low energy, rovibronic interactions play a significant role in the dynamics, whereas at high energy, the dissociative excitation strongly competes with all other reactive processes.

  18. Effect of Plasma, RF, and RIE Treatments on Properties of Double-Sided High Voltage Solar Cells with Vertically Aligned p-n Junctions

    Directory of Open Access Journals (Sweden)

    Mykola O. Semenenko

    2016-01-01

    Full Text Available Si-based solar cells with vertically aligned p-n junctions operating at high voltage were designed and fabricated. The plasma treatments and antireflection coating deposition on the working surfaces of both single- and multijunction cells were made using the special holders. It was shown that additional treatment of solar cells in argon plasma prior to hydrogen plasma treatment and deposition of diamond-like carbon antireflection films led to the improvement of the cell efficiency by up to 60%. Radio frequency waves support plasma generation and improve photoelectric conversion mainly due to reduction of internal stresses at the interfaces. Application of reactive ion etching technique removes the broken layer, reduces elastic strain in the wafer, decreases recombination of charge carriers in the bulk, and provides cell efficiency increase by up to ten times.

  19. Physics of Collisional Plasmas Introduction to High-Frequency Discharges

    CERN Document Server

    Moisan, Michel

    2012-01-01

    The Physics of Collisional Plasmas deals with the plasma physics of interest to laboratory research and industrial applications, such as lighting, fabrication of microelectronics, destruction of greenhouse gases. Its emphasis is on explaining the physical mechanisms, rather than the detailed mathematical description and theoretical analysis. At the introductory level, it is important to convey the characteristic physical phenomena of plasmas, before addressing the ultimate formalism of kinetic theory, with its microscopic, statistical mechanics approach. To this aim, this text translates the physical phenomena into more tractable equations, using the hydrodynamic model; this considers the plasma as a fluid, in which the macroscopic physical parameters are the statistical averages of the microscopic (individual) parameters. This book is an introduction to the physics of collisional plasmas, as opposed to plasmas in space. It is intended for graduate students in physics and engineering . The first chapter intr...

  20. Blistering on tungsten surface exposed to high flux deuterium plasma

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H.Y., E-mail: donaxu@163.com [Center of Interface Dynamics for Sustainability, Institute of Materials, CAEP, Chengdu 610200 (China); Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu, W., E-mail: liuw@mail.tsinghua.edu.cn [Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Luo, G.N. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Yuan, Y. [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China); Jia, Y.Z.; Fu, B.Q. [Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); De Temmerman, G. [FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research, Trilateral Euregio Cluster, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); ITER Organization, Route de Vinon-sur-Verdon CS 90046-13067, St Paul Lez Durance Cedex (France)

    2016-04-01

    The blistering behaviour of tungsten surfaces exposed to very high fluxes (1–2 × 10{sup 24}/m{sup 2}/s) of low energy (38 eV) deuterium plasmas was investigated as a function of ion fluence (0.2–7 × 10{sup 26} D/m{sup 2}) and surface temperature (423–873 K). Blisters were observed under all conditions, especially up to temperatures of 873 K. The blister parameters are evaluated with blister size, blister density and surface coverage. The blister size always peaked at less than 0.5 μm and no blister larger than 10 μm is observed even at high fluence. The blister densities are found in high magnitude of 10{sup 6} blisters/m{sup 2}, with the surface coverages lower than 2%. The formation of cracks in the sub-surface region was observed by cross-section imaging. Changes in blister size and shape with fluence and temperature suggest processes of predominantly nucleation and subsequent growth of blisters. The smaller blister size is considered to be caused by a combination of flux-related effects such as enhanced defect formation in the near surface region, reduced deuterium diffusivity and relatively short exposure times.

  1. High Power, Solid-State RF Generation for Plasma Heating

    Science.gov (United States)

    Prager, James; Ziemba, Timothy; Miller, Kenneth; Pierren, Chris

    2016-10-01

    Radio Frequency heating systems are rarely used by the small-scale validation platform experiments due to the high cost and complexity of these systems. Eagle Harbor Technologies (EHT), Inc. is developing an all-solid-state RF plasma heating system that uses EHT's nanosecond pulser technology in an inductive adder configuration to drive nonlinear transmission lines (NLTL). The system under development does not require the use of vacuum tube technology, is inherently lower cost, and is more robust than traditional high power RF heating schemes. The inductive adder can produce 0 to20 kV pulses into 50 Ohms with sub-10 ns rise times. The inductive adder has been used to drive NLTLs near 2 GHz with other frequencies to be tested in the future. EHT will present experimental results, including RF measurements with D-dot probes and capacitve voltage probes. During this program, EHT will test the system on Helicity Injected Torus at the University of Washington and the High Beta Tokamak at Columbia University.

  2. Blistering on tungsten surface exposed to high flux deuterium plasma

    Science.gov (United States)

    Xu, H. Y.; Liu, W.; Luo, G. N.; Yuan, Y.; Jia, Y. Z.; Fu, B. Q.; De Temmerman, G.

    2016-04-01

    The blistering behaviour of tungsten surfaces exposed to very high fluxes (1-2 × 1024/m2/s) of low energy (38 eV) deuterium plasmas was investigated as a function of ion fluence (0.2-7 × 1026 D/m2) and surface temperature (423-873 K). Blisters were observed under all conditions, especially up to temperatures of 873 K. The blister parameters are evaluated with blister size, blister density and surface coverage. The blister size always peaked at less than 0.5 μm and no blister larger than 10 μm is observed even at high fluence. The blister densities are found in high magnitude of 106 blisters/m2, with the surface coverages lower than 2%. The formation of cracks in the sub-surface region was observed by cross-section imaging. Changes in blister size and shape with fluence and temperature suggest processes of predominantly nucleation and subsequent growth of blisters. The smaller blister size is considered to be caused by a combination of flux-related effects such as enhanced defect formation in the near surface region, reduced deuterium diffusivity and relatively short exposure times.

  3. Coaxial plasma thrusters for high specific impulse propulsion

    Science.gov (United States)

    Schoenberg, Kurt F.; Gerwin, Richard A.; Barnes, Cris W.; Henins, Ivars; Mayo, Robert; Moses, Ronald, Jr.; Scarberry, Richard; Wurden, Glen

    1991-01-01

    A fundamental basis for coaxial plasma thruster performance is presented and the steady-state, ideal MHD properties of a coaxial thruster using an annular magnetic nozzle are discussed. Formulas for power usage, thrust, mass flow rate, and specific impulse are acquired and employed to assess thruster performance. The performance estimates are compared with the observed properties of an unoptimized coaxial plasma gun. These comparisons support the hypothesis that ideal MHD has an important role in coaxial plasma thruster dynamics.

  4. Gene Transfer of Tumor-Reactive TCR Confers Both High Avidity and Tumor Reactivity to Nonreactive Peripheral Blood Mononuclear Cells and Tumor-Infiltrating Lymphocytes1

    Science.gov (United States)

    Johnson, Laura A.; Heemskerk, Bianca; Powell, Daniel J.; Cohen, Cyrille J.; Morgan, Richard A.; Dudley, Mark E.; Robbins, Paul F.; Rosenberg, Steven A.

    2007-01-01

    Cell-based antitumor immunity is driven by CD8+ cytotoxic T cells bearing TCR that recognize specific tumor-associated peptides bound to class I MHC molecules. Of several cellular proteins involved in T cell:target-cell interaction, the TCR determines specificity of binding; however, the relative amount of its contribution to cellular avidity remains unknown. To study the relationship between TCR affinity and cellular avidity, with the intent of identifying optimal TCR for gene therapy, we derived 24 MART-1:27–35 (MART-1) melanoma Ag-reactive tumor-infiltrating lymphocyte (TIL) clones from the tumors of five patients. These MART-1-reactive clones displayed a wide variety of cellular avidities. α and β TCR genes were isolated from these clones, and TCR RNA was electroporated into the same non-MART-1-reactive allogeneic donor PBMC and TIL. TCR recipient cells gained the ability to recognize both MART-1 peptide and MART-1-expressing tumors in vitro, with avidities that closely corresponded to the original TCR clones (p = 0.018–0.0003). Clone DMF5, from a TIL infusion that mediated tumor regression clinically, showed the highest avidity against MART-1 expressing tumors in vitro, both endogenously in the TIL clone, and after RNA electroporation into donor T cells. Thus, we demonstrated that the TCR appeared to be the core determinant of MART-1 Ag-specific cellular avidity in these activated T cells and that nonreactive PBMC or TIL could be made tumor-reactive with a specific and predetermined avidity. We propose that inducing expression of this highly avid TCR in patient PBMC has the potential to induce tumor regression, as an “off-the-shelf” reagent for allogeneic melanoma patient gene therapy. PMID:17056587

  5. High C-Reactive Protein Predicts Delirium Incidence, Duration, and Feature Severity After Major Noncardiac Surgery.

    Science.gov (United States)

    Vasunilashorn, Sarinnapha M; Dillon, Simon T; Inouye, Sharon K; Ngo, Long H; Fong, Tamara G; Jones, Richard N; Travison, Thomas G; Schmitt, Eva M; Alsop, David C; Freedman, Steven D; Arnold, Steven E; Metzger, Eran D; Libermann, Towia A; Marcantonio, Edward R

    2017-08-01

    To examine associations between the inflammatory marker C-reactive protein (CRP) measured preoperatively and on postoperative day 2 (POD2) and delirium incidence, duration, and feature severity. Prospective cohort study. Two academic medical centers. Adults aged 70 and older undergoing major noncardiac surgery (N = 560). Plasma CRP was measured using enzyme-linked immunosorbent assay. Delirium was assessed from Confusion Assessment Method (CAM) interviews and chart review. Delirium duration was measured according to number of hospital days with delirium. Delirium feature severity was defined as the sum of CAM-Severity (CAM-S) scores on all postoperative hospital days. Generalized linear models were used to examine independent associations between CRP (preoperatively and POD2 separately) and delirium incidence, duration, and feature severity; prolonged hospital length of stay (LOS, >5 days); and discharge disposition. Postoperative delirium occurred in 24% of participants, 12% had 2 or more delirium days, and the mean ± standard deviation sum CAM-S was 9.3 ± 11.4. After adjusting for age, sex, surgery type, anesthesia route, medical comorbidities, and postoperative infectious complications, participants with preoperative CRP of 3 mg/L or greater had a risk of delirium that was 1.5 times as great (95% confidence interval (CI) = 1.1-2.1) as that of those with CRP less than 3 mg/L, 0.4 more delirium days (P delirium (3.6 CAM-S points higher, P delirium (95% CI = 1.0-2.4) as those in the lowest quartile (≤127.53 mg/L), had 0.2 more delirium days (P delirium (4.5 CAM-S points higher, P delirium incidence, duration, and feature severity. CRP may be useful to identify individuals who are at risk of developing delirium. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

  6. Electromagnetic instability in high-beta plasmas with generalized distribution functions

    Science.gov (United States)

    Buti, B.

    1974-01-01

    The electrostatic instabilities in an anisotropic plasma have been studied quite extensively, but the electromagnetic instabilities in high-beta plasmas, where they play an important role, have not been thoroughly investigated. Recently, Davidson and Wu (1970) looked into the ordinary mode electromagnetic instability which can arise in high-beta bi-Maxwellian plasmas. Here, the magnetic instability is discussed in (A, beta) space (A is the anisotropy in the temperature of the plasma species and beta is the ratio of the kinetic pressure to the magnetic pressure), which can occur in generalized non-Maxwellian plasmas with an inverted population of different species.

  7. Room temperature plasma oxidation: A new process for preparation of ultrathin layers of silicon oxide, and high dielectric constant materials

    Energy Technology Data Exchange (ETDEWEB)

    Tinoco, J.C. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico) and Facultad de Ingenieria y Arquitectura, Universidad de San Martin de Porres (FIA-USMP), Av. La Fontana 1250, La Molina, Lima 12 (Peru)]. E-mail: jcesartinoco@yahoo.com.mx; Estrada, M. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico)]. E-mail: mestrada@mail.cinvestav.mx; Baez, H. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico); Cerdeira, A. [Seccion de Electronica del Estado Solido, Depto. Ingenieria Electrica, CINVESTAV-IPN, Av. IPN, No. 2508, CP 07730, Mexico D.F. (Mexico)

    2006-02-21

    In this paper we present basic features and oxidation law of the room temperature plasma oxidation (RTPO), as a new process for preparation of less than 2 nm thick layers of SiO{sub 2}, and high-k layers of TiO{sub 2}. We show that oxidation rate follows a potential law dependence on oxidation time. The proportionality constant is function of pressure, plasma power, reagent gas and plasma density, while the exponent depends only on the reactive gas. These parameters are related to the physical phenomena occurring inside the plasma, during oxidation. Metal-Oxide-Semiconductor (MOS) capacitors fabricated with these layers are characterized by capacitance-voltage, current-voltage and current-voltage-temperature measurements. Less than 2.5 nm SiO{sub 2} layers with surface roughness similar to thermal oxide films, surface state density below 3 x 10{sup 11} cm{sup -2} and current density in the expected range for each corresponding thickness, were obtained by RTPO in a parallel-plate reactor, at 180 mW/cm{sup 2} and pressure range between 9.33 and 66.5 Pa (0.07 and 0.5 Torr) using O{sub 2} and N{sub 2}O as reactive gases. MOS capacitors with TiO{sub 2} layers formed by RTPO of sputtered Ti layers are also characterized. Finally, MOS capacitors with stacked layers of TiO{sub 2} over SiO{sub 2}, both layers obtained by RTPO, were prepared and evaluated to determine the feasibility of the use of TiO{sub 2} as a candidate for next technology nodes.

  8. Compatibility of advanced tokamak plasma with high density and high radiation loss operation in JT-60U

    Science.gov (United States)

    Takenaga, H.; Asakura, N.; Kubo, H.; Higashijima, S.; Konoshima, S.; Nakano, T.; Oyama, N.; Porter, G. D.; Rognlien, T. D.; Rensink, M. E.; Ide, S.; Fujita, T.; Takizuka, T.; Kamada, Y.; Miura, Y.; JT-60 Team

    2005-12-01

    Compatibility of advanced tokamak plasmas with high density and high radiation loss has been investigated in both reversed shear (RS) plasmas and high βp H-mode plasmas with a weak positive shear on JT-60U. In the RS plasmas, the operating regime is extended to high density above the Greenwald density (nGW) with high confinement (HHy2 > 1) and high radiation loss fraction (frad > 0.9) by tailoring the internal transport barriers (ITBs). With a small plasma-wall gap, the radiation loss in the main plasma (inside the magnetic separatrix) reaches 80% of the heating power due to metal impurity accumulation. However, high confinement of HHy2 = 1.2 is sustained even with such a large radiation loss in the main plasma. By neon seeding, the divertor radiation loss is enhanced from 20% to 40% of the total radiation loss. In the high βp H-mode plasmas, high confinement (HHy2 = 0.96) is maintained at high density ( \\bar{n}_{\\rme}/n_GW=0.92 ) with high radiation loss fraction (frad ~ 1) by utilizing high-field-side pellets and argon (Ar) injection. The high \\bar{n}_{\\rme}/n_GW is attributed to the formation of strong density ITB. Strong core-edge parameter linkage for confinement improvement is observed, where the pedestal pressure and the core plasma confinement increase together. The measured radiation profile including contributions from all impurities in the main plasma is peaked, and the central radiation is ascribed to the contribution from Ar accumulated inside the ITB. Impurity transport analyses indicate that the Ar density profile, twice as peaked as the electron density profile, which is the same level as that observed in the high βp H-mode plasma, can yield an acceptable radiation profile even with a peaked density profile in a fusion reactor.

  9. Plasma behaviour at high beta and high density in the Madison Symmetric Torus RFP

    Energy Technology Data Exchange (ETDEWEB)

    Wyman, M. [University of Wisconsin, Madison; Chapman, B. E. [University of Wisconsin, Madison; Ahn, J. W. [University of Wisconsin, Madison; Almagri, A. F. [University of Wisconsin, Madison; Anderson, J. [University of Wisconsin, Madison; Bonomo, F. [Consorzio RFX, Italy; Bower, D L [University of California, Los Angeles; Combs, Stephen Kirk [ORNL; Craig, D. [University of Wisconsin, Madison; Foust, Charles R [ORNL

    2009-01-01

    Pellet fuelling of improved confinement Madison Symmetric Torus (MST) plasmas has resulted in high density and high plasma beta. The density in improved confinement discharges has been increased fourfold, and a record plasma beta (beta(tot) = 26%) for the improved confinement reversed-field pinch (RFP) has been achieved. At higher beta, a new regime for instabilities is accessed in which local interchange and global tearing instabilities are calculated to be linearly unstable, but experimentally, no severe effect, e. g., a disruption, is observed. The tearing instability, normally driven by the current gradient, is driven by the pressure gradient in this case, and there are indications of increased energy transport ( as compared with low-density improved confinement). Pellet fuelling is also compared with enhanced edge fuelling of standard confinement RFP discharges for the purpose of searching for a density limit in MST. In standard-confinement discharges, pellet fuelling peaks the density profile where edge fuelling cannot, but transport appears unchanged. For a limited range of plasma current, MST discharges with edge fuelling are constrained to a maximum density corresponding to the Greenwald limit. This limit is surpassed in pellet-fuelled improved confinement discharges.

  10. Reactive species output of a plasma jet with a shielding gas device—combination of FTIR absorption spectroscopy and gas phase modelling

    Science.gov (United States)

    Schmidt-Bleker, A.; Winter, J.; Iseni, S.; Dünnbier, M.; Weltmann, K.-D.; Reuter, S.

    2014-04-01

    In this work, a simple modelling approach combined with absorption spectroscopy of long living species generated by a cold atmospheric plasma jet yields insight into relevant gas phase chemistry. The reactive species output of the plasma jet is controlled using a shielding gas device. The shielding gas is varied using mixtures of oxygen and nitrogen at various humidity levels. Through the combination of Fourier transform infrared (FTIR) spectroscopy, computational fluid dynamics (CFD) simulations and zero dimensional kinetic modelling of the gas phase chemistry, insight into the underlying reaction mechanisms is gained. While the FTIR measurements yield absolute densities of ozone and nitrogen dioxide in the far field of the jet, the kinetic simulations give additional information on reaction pathways. The simulation is fitted to the experimentally obtained data, using the CFD simulations of the experimental setup to estimate the correct evaluation time for the kinetic simulation. It is shown that the ozone production of the plasma jet continuously rises with the oxygen content in the shielding gas, while it significantly drops as humidity is increased. The production of nitrogen dioxide reaches its maximum at about 30% oxygen content in the shielding gas. The underlying mechanisms are discussed based on the simulation results.

  11. The effect of inductively-coupled-plasma reactive ion etching power on the etching rate and the surface roughness of a sapphire substrate.

    Science.gov (United States)

    Chang, Chun-Ming; Shiao, Ming-Hua; Yang, Chin-Tien; Cheng, Chung-Ta; Hsueh, Wen-Jeng

    2014-10-01

    In this study, patterned sapphire substrates are fabricated using nanosphere lithography (NSL) and inductively-coupled-plasma reactive ion etching (ICP-RIE). Polystyrene nanospheres of approximately 600 nm diameter are self-assembled on c-plane sapphire substrates by spin-coating. The diameter of the polystyrene nanospheres is modified to adjust the etching mask pitch cycle using oxygen plasma in the ICP-RIE system. A nickel thin film mask of 100 nm thickness is deposited by electron-beam evaporation on a substrate covered with treated nanospheres. The sapphire substrate is then etched in an inductively coupled plasma system using BCl3/Ar gas, to fabricate a structure with a periodic sub-micron hole array with different sidewall intervals. The DC bias voltage, the sapphire etching rate, the surface roughness, are studied as a function of the ICP and the RF power. Different sub-micron hole arrays with spacing cycles of 89 nm, 139 nm and 167 nm are successfully fabricated on the sapphire substrate, using suitable etching parameters.

  12. Surface morphology and deuterium retention in tungsten exposed to high flux D plasma at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Y.Z. [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); De Temmerman, G. [FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research, Edisonbaan 14, 3439 MN Nieuwegein (Netherlands); ITER Organization, Route de Vinon-sur-Verdon-CS90046, 13067 St Paul Lez Durance Cedex (France); Luo, G.-N. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031 (China); Xu, H.Y. [Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang, Sichuan 621907 (China); Li, C.; Fu, B.Q. [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu, W., E-mail: liuw@mail.tsinghua.edu.cn [Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2015-02-15

    Surface modifications and deuterium retention induced in tungsten by high fluxes (10{sup 24} m{sup −2} s{sup −1}) low energy (38 eV) deuterium ions were studied as a function of surface temperature. Blister formation was studied by scanning electron microscopy and electron backscatter diffraction, while deuterium retention was measured by thermal desorption spectroscopy. Blisters are observed on the surface exposed at different temperatures, ranging from 493 K to 1273 K. The blister density and D retention decrease with the increasing exposure temperature. The formation of blisters at high temperatures is attributed to the high flux of D plasma. At 943 K, with the increasing fluence, there is trend to the saturation of D retention and blister density. The defects caused by plasma exposure have an important effect on the D trapping and blistering behavior. The formation of blisters has a strong relationship with slipping system of tungsten.

  13. High-temperature thermal degradation of polyethylene from reactive molecular dynamics

    Science.gov (United States)

    Lane, J. Matthew D.; Moore, Nathan W.

    Thermal degradation of polyethylene is studied under extremely high-rate temperature ramp rates from 1014 to 1010 K/s in isochoric, condensed phases. The molecular evolution and macroscopic state variables are extracted as a function of density from reactive molecular dynamics simulations using the ReaxFF potential. These results are used to parameterize a kinetic rate model for the dissociation and coalescence of hydrocarbons as a function of temperature, temperature ramp rate, and density. The results are contrasted to first-order random-scission macrokinetic models often assumed for pyrolysis of linear polyethylene under ambient conditions. Sandia National Laboratories is a multi program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04- 94AL85000.

  14. Patterned Platinum Etching Studies in an Argon High Density Plasma

    Science.gov (United States)

    Delprat, Sébastien; Chaker, Mohamed; Margot, Joëlle; Pépin, Henri; Tan, Liang; Smy, Tom

    1998-10-01

    A high-density surface-wave Ar plasma operated in the low pressure regime is used to study pure physical etching characteristics of platinum thin films. The platinum samples are RF biased so as to obtain a maximum DC self-bias voltage of 150 V. The sputter-etching characteristics are investigated as a function of the magnetic field intensity, the self-bias voltage and the gas pressure. At 1 mtorr, the etch rate is found to be a unique linear function of both the self-bias voltage and the ion density, independently of the magnetic field intensity value. However, even though the ion density increases, the etch rate is found to decrease with increasing pressure. In the low pressure regime, etch rates as high as 2000 A/min are obtained with a good selectivity over resist. Without any optimization of the etching process, we were able to etch 0.5 micron Pt trenches, 0.6 micron thick yielding fence-free profiles and sidewall angles (75º) that already meets the present industrial requirements of NVRAM technology.

  15. THE TURBULENT DYNAMO IN HIGHLY COMPRESSIBLE SUPERSONIC PLASMAS

    Energy Technology Data Exchange (ETDEWEB)

    Federrath, Christoph [Research School of Astronomy and Astrophysics, The Australian National University, Canberra, ACT 2611 (Australia); Schober, Jennifer [Universität Heidelberg, Zentrum für Astronomie, Institut für Theoretische Astrophysik, Albert-Ueberle-Strasse 2, D-69120 Heidelberg (Germany); Bovino, Stefano; Schleicher, Dominik R. G., E-mail: christoph.federrath@anu.edu.au [Institut für Astrophysik, Georg-August-Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen (Germany)

    2014-12-20

    The turbulent dynamo may explain the origin of cosmic magnetism. While the exponential amplification of magnetic fields has been studied for incompressible gases, little is known about dynamo action in highly compressible, supersonic plasmas, such as the interstellar medium of galaxies and the early universe. Here we perform the first quantitative comparison of theoretical models of the dynamo growth rate and saturation level with three-dimensional magnetohydrodynamical simulations of supersonic turbulence with grid resolutions of up to 1024{sup 3} cells. We obtain numerical convergence and find that dynamo action occurs for both low and high magnetic Prandtl numbers Pm = ν/η = 0.1-10 (the ratio of viscous to magnetic dissipation), which had so far only been seen for Pm ≥ 1 in supersonic turbulence. We measure the critical magnetic Reynolds number, Rm{sub crit}=129{sub −31}{sup +43}, showing that the compressible dynamo is almost as efficient as in incompressible gas. Considering the physical conditions of the present and early universe, we conclude that magnetic fields need to be taken into account during structure formation from the early to the present cosmic ages, because they suppress gas fragmentation and drive powerful jets and outflows, both greatly affecting the initial mass function of stars.

  16. Effects of Biomass Feedstock on the Yield and Reactivity of Soot from Fast Pyrolysis at High Temperatures

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Jensen, Peter A.; Glarborg, Peter

    This study investigated the effect of feedstock on the yield, nanostructure and reactivity of soot. Woody and herbaceous biomass were pyrolyzed at high heating rates and temperatures of 1250 and 1400°C in a drop tube furnace. The collected solid residues were structurally characterized by electron...... microscopy techniques, X-ray diffraction and N2-adsorption. The reactivity of soot was investigated by thermogravimetric analysis. The results showed that the reactivity of soot, generated at 1400°C was higher than that at 1250°C for all biomass types. Wood and wheat straw soot demonstrated differences...... with respect to the alkali content, particle size and nanostructure. Potassium was incorporated in the soot matrix and to a significant extent influenced the soot reactivity. The particle size distribution of pinewood soot produced at 1250°C was in the range from 27.2 to 263 nm which was broader compared...

  17. Plasma scale-length effects on electron energy spectra in high-irradiance laser plasmas

    Science.gov (United States)

    Culfa, O.; Tallents, G. J.; Rossall, A. K.; Wagenaars, E.; Ridgers, C. P.; Murphy, C. D.; Dance, R. J.; Gray, R. J.; McKenna, P.; Brown, C. D. R.; James, S. F.; Hoarty, D. J.; Booth, N.; Robinson, A. P. L.; Lancaster, K. L.; Pikuz, S. A.; Faenov, A. Ya.; Kampfer, T.; Schulze, K. S.; Uschmann, I.; Woolsey, N. C.

    2016-04-01

    An analysis of an electron spectrometer used to characterize fast electrons generated by ultraintense (1020W cm-2 ) laser interaction with a preformed plasma of scale length measured by shadowgraphy is presented. The effects of fringing magnetic fields on the electron spectral measurements and the accuracy of density scale-length measurements are evaluated. 2D EPOCH PIC code simulations are found to be in agreement with measurements of the electron energy spectra showing that laser filamentation in plasma preformed by a prepulse is important with longer plasma scale lengths (>8 μ m ).

  18. Electron Cyclotron Resonance Heating of a High-Density Plasma

    DEFF Research Database (Denmark)

    Hansen, F. Ramskov

    1986-01-01

    Various schemes for electron cyclotron resonance heating of tokamak plasmas with the ratio of electron plasma frequency to electron cyclotron frequency, "»pe/^ce* larger than 1 on axis, are investigated. In particular, a mode conversion scheme is investigated using ordinary waves at the fundamental...

  19. Removal of carbon deposited film and hydrogen retention control by low temperature H–C–N reactive plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, A., E-mail: me121030@ec.t.kanazawa-u.ac.jp [Kanazawa University, Kanazawa, Ishikawa (Japan); Takai, Y.; Uesugi, Y.; Tanaka, Y.; Ishijima, T. [Kanazawa University, Kanazawa, Ishikawa (Japan); Masuzaki, S. [NIFS, Toki, Gifu (Japan)

    2013-07-15

    Control of tritium retention and its removal from the first wall of future fusion devices are the most crucial issues for safety and effective use of the fuel. Nitrogen injection into edge plasmas has been considered and tested as an effective method for suppression of carbon dust growth and reduction of hydrogen isotope inventory. In this paper we have investigated scavenger effects of nitrogen injected into H{sub 2}/CH{sub 4} plasmas using a small helical device where low density (n{sub e} ∼ 10{sup 16} m{sup −3}) and low temperature (T{sub e} = 5–10 eV) hydrogen plasmas are generated in steady state condition like remote plasmas in fusion devices. It is shown from the comparison of the carbon film deposition and particle growth between those with and without N{sub 2} injection that the chemical erosion effects of nitrogen gas on the carbon film and particle growth strongly depends on the surface temperature. With increasing the surface temperature higher than ∼400 K, the nitrogen chemical erosion significantly works to reduce the hydrocarbon deposition.

  20. High Energy-Density Plasma Dynamics in Plasma-Filled Rod-Pinch Diodes

    Science.gov (United States)

    2013-06-01

    at about 30 eV at the time of maximum energy density, and that the time-averaged ionization is about +17, similar to MHD model predictions [2... MHD model predictions [2]. The plasma mass distribution is inferred from x-ray distribution measurements. The time-dependent mass distribution is used...Previous modeling [2] assumed the tungsten plasma had a time-dependent Gaussian radial profile and a fixed length of 3.5 mm, consistent with time

  1. Relationships of High-sensitive C-reactive Protein and P-wave Dispersion in Lone Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Li-Hui Zheng

    2015-01-01

    Full Text Available Background: Current evidence links atrial fibrillation (AF to the inflammation. Inflammatory indexes such as high-sensitive C-reactive protein (hs-CRP have been related to the development and persistence of AF. However, the role of inflammation in the atrial electrophysiological remodeling indexed by P-wave dispersion (P d remains unclear. Methods: The study consisted of 71 patients with lone paroxysmal AF (AF group and 71 age- and gender-matched controls of paroxysmal supraventricular tachycardia without history of AF (control group. Electrocardiography, P d , hs-CRP, and other clinical characteristics were compared between the two groups. Results: There was no significant difference between the two groups regarding age, gender, hyperlipidemia, etc. Compared to controls, left atrial diameter (44 ± 7 vs 39 ± 7 mm, P d (49 ± 13 vs 26 ± 8 ms, and hs-CRP (2.17 [1.46-2.89] vs 1.12 [0.74-1.41] mg/L were increased (P < 0.05, respectively. Linear regression identified hs-CRP as an independent correlation of P d level both in the total population and the AF group (r = 0.464 and 0.313; P < 0.001, respectively. Multiple logistic regression revealed hs-CRP as an independent determinant of AF (odds ratio [OR] =15.430, 95% confidence interval: 6.031-39.476: P <0.001. Further adjusted for P d , both P d and hs-CRP were independent predictors for AF, but the OR for hs-CRP in predicting AF has been attenuated from 15.430 to 6.246. Conclusions: In lone AF, P d and plasma hs-CRP concentration are inter-associated and related to AF. The interaction between hs-CRP and AF may be mediated by P d , suggesting an important role of inflammation in the atrial electrophysiological remodeling predisposing to AF.

  2. Characterization Of High Explosives Detonations Via Laser-Induced Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-08

    One objective of the Department of Energy’s National Security Administration is to develop technologies that can help the United States government to detect foreign nuclear weapons development activities. The realm of high explosive (HE) experiments is one of the key areas to assess the nuclear ambitions of a country. SRNL has participated in the collection of particulates from HE experiments and characterized the material with the purpose to correlate particulate matter with HE. Since these field campaigns are expensive, on-demand simulated laboratory-scale explosion experiments are needed to further our knowledge of the chemistry and particle formation in the process. Our goal is to develop an experimental test bed in the laboratory to test measurement concepts and correlate particle formation processes with the observables from the detonation fireball. The final objective is to use this knowledge to tailor our experimental setups in future field campaigns. The test bed uses pulsed laser-induced plasmas to simulate micro-explosions, with the intent to study the temporal behavior of the fireball observed in field tests. During FY15, a plan was prepared and executed which assembled two laser ablation systems, procured materials for study, and tested a Step-Scan Fourier Transform Infrared Spectrometer (SS-FTIR). Designs for a shadowgraph system for shock wave analysis, design for a micro-particulate collector from ablated pulse were accomplished. A novel spectroscopic system was conceived and a prototype system built for acquisition of spectral/temporal characterization of a high speed event such as from a high explosive detonation. Experiments and analyses will continue into FY16.

  3. Consensus and future directions on the definition of high on-treatment platelet reactivity to adenosine diphosphate.

    Science.gov (United States)

    Bonello, Laurent; Tantry, Udaya S; Marcucci, Rossella; Blindt, Ruediger; Angiolillo, Dominick J; Becker, Richard; Bhatt, Deepak L; Cattaneo, Marco; Collet, Jean Philippe; Cuisset, Thomas; Gachet, Christian; Montalescot, Gilles; Jennings, Lisa K; Kereiakes, Dean; Sibbing, Dirk; Trenk, Dietmar; Van Werkum, Jochem W; Paganelli, Franck; Price, Matthew J; Waksman, Ron; Gurbel, Paul A

    2010-09-14

    The addition of clopidogrel to aspirin treatment reduces ischemic events in a wide range of patients with cardiovascular disease. However, recurrent ischemic event occurrence during dual antiplatelet therapy, including stent thrombosis, remains a major concern. Platelet function measurements during clopidogrel treatment demonstrated a variable and overall modest level of P2Y(12) inhibition. High on-treatment platelet reactivity to adenosine diphosphate (ADP) was observed in selected patients. Multiple studies have now demonstrated a clear association between high on-treatment platelet reactivity to ADP measured by multiple methods and adverse clinical event occurrence. However, the routine measurement of platelet reactivity has not been widely implemented and recommended in the guidelines. Reasons for the latter include: 1) a lack of consensus on the optimal method to quantify high on-treatment platelet reactivity and the cutoff value associated with clinical risk; and 2) limited data to support that alteration of therapy based on platelet function measurements actually improves outcomes. This review provides a consensus opinion on the definition of high on-treatment platelet reactivity to ADP based on various methods reported in the literature and proposes how this measurement may be used in the future care of patients. Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  4. Gamma glutamyltransferase levels and its association with high sensitive C-reactive protein in patients with acute coronary syndromes

    Science.gov (United States)

    Emiroglu, Mehmet Yunus; Esen, Özlem Batukan; Bulut, Mustafa; Karapinar, Hekim; Kaya, Zekeriya; Akcakoyun, Mustafa; Kargin, Ramazan; Aung, Soe Moe; Alızade, Elnur; Pala, Selcuk; Esen, Ali Metin

    2010-01-01

    Background: Elevated Gamma-glutamyltransferase (GGT) level is independently correlated with conditions associatedwith increased atherosclerosis, such as obesity, elevated serum cholesterol, high blood pressure and myocardial infarction. It is also demonstrated that serum gamma-glutamyltransferase activity is an independent risk factor for myocardial infarction and cardiac death in patients with coronary artery disease. Although the relationship between gamma-glutamyltransferase and coronary artery disease has been reported, not many studies have shown the relationship between changes ofgamma-glutamyltransferase in acute coronary syndromes and a well established coronary risk factor high sensitive C-reactive protein. (hs-CRP). Aims: In this study, how gamma-glutamyltransferase levels changed in acute coronary syndromes and its relationship with high sensitive C-reactive protein if any were studied. Patients & Methods: This trial was carried out at Kosuyolu Cardiovascular Training and Research Hospital and Van Yuksek Ihtisas Hospital, Turkey. 219 patients (177 males and 42 females) presenting with acute coronary syndrome, and 51 control subjects between September 2007 and September 2008 were included in the study. Serum gamma-glutamyltransferase, high sensitive C-reactive protein, serum lipoprotein levels and troponin I were determined. Results: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients compared to control. There was also correlation between gamma-glutamyltransferase and high sensitive C-reactive protein levels. Conclusion: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients. In subgroup analyses, the higher difference with Non-ST elevation myocardial infarction and ST elevation myocardial infarction groups than unstable angina oectoris group proposes a relationship between gamma-glutamyltransferase and severity

  5. Gamma glutamyltransferase levels and its association with high sensitive C-reactive protein in patients with acute coronary syndromes

    Directory of Open Access Journals (Sweden)

    Mehmet Yunus Emiroglu

    2010-07-01

    Full Text Available Background: Elevated Gamma-glutamyltransferase (GGT level is independently correlated with conditions associatedwith increased atherosclerosis, such as obesity, elevated serum cholesterol, high blood pressure and myocardial infarction. It is also demonstrated that serum gamma-glutamyltransferase activity is an independent risk factor for myocardial infarction and cardiac death in patients with coronary artery disease. Although the relationship between gamma-glutamyltransferase and coronary artery disease has been reported, not many studies have shown the relationship between changes ofgamma-glutamyltransferase in acute coronary syndromes and a well established coronary risk factor high sensitive C-reactive protein. (hs-CRP. Aims: In this study, how gamma-glutamyltransferase levels changed in acute coronary syndromes and its relationship with high sensitive C-reactive protein if any were studied. Patients & Methods:This trial was carried out at Kosuyolu Cardiovascular Training and Research Hospital and Van Yuksek Ihtisas Hospital, Turkey. 219 patients (177 males and 42 females presenting with acute coronary syndrome, and 51 control subjects between September 2007 and September 2008 were included in the study. Serum gamma-glutamyltransferase, high sensitive C-reactive protein, serum lipoprotein levels and troponin I were determined. Results: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients compared to control. There was also correlation between gamma-glutamyltransferase and high sensitive C-reactive protein levels. Conclusion: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients. In subgroup analyses, the higher difference with Non-ST elevation myocardial infarction and ST elevation myocardial infarction groups than unstable angina oectoris group proposes a relationship between gamma

  6. Gamma glutamyltransferase levels and its association with high sensitive C-reactive protein in patients with acute coronary syndromes

    Directory of Open Access Journals (Sweden)

    Mehmet Yunus Emiroglu

    2010-01-01

    Full Text Available Background: Elevated Gamma-glutamyltransferase (GGT level is independently correlated with conditions associatedwith increased atherosclerosis, such as obesity, elevated serum cholesterol, high blood pressure and myocardial infarction. It is also demonstrated that serum gamma-glutamyltransferase activity is an independent risk factor for myocardial infarction and cardiac death in patients with coronary artery disease. Although the relationship between gamma-glutamyltransferase and coronary artery disease has been reported, not many studies have shown the relationship between changes ofgamma-glutamyltransferase in acute coronary syndromes and a well established coronary risk factor high sensitive C-reactive protein. (hs-CRP. Aims: In this study, how gamma-glutamyltransferase levels changed in acute coronary syndromes and its relationship with high sensitive C-reactive protein if any were studied. Patients & Methods: This trial was carried out at Kosuyolu Cardiovascular Training and Research Hospital and Van Yuksek Ihtisas Hospital, Turkey. 219 patients (177 males and 42 females presenting with acute coronary syndrome, and 51 control subjects between September 2007 and September 2008 were included in the study. Serum gamma-glutamyltransferase, high sensitive C-reactive protein, serum lipoprotein levels and troponin I were determined. Results: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients compared to control. There was also correlation between gamma-glutamyltransferase and high sensitive C-reactive protein levels. Conclusion: Serum gamma-glutamyltransferase and high sensitive C-reactive protein levels were higher in acute coronary syndrome patients. In subgroup analyses, the higher difference with Non-ST elevation myocardial infarction and ST elevation myocardial infarction groups than unstable angina oectoris group proposes a relationship between gamma

  7. US-Japan workshop Q-181 on high heat flux components and plasma-surface interactions for next devices: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, R.T. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Yamashina, T. [ed.] [Hokkadio Univ. (Japan)

    1994-04-01

    This report contain viewgraphs of papers from the following sessions: plasma facing components issues for future machines; recent PMI results from several tokamaks; high heat flux technology; plasma facing components design and applications; plasma facing component materials and irradiation damage; boundary layer plasma; plasma disruptions; conditioning and tritium; and erosion/redeposition.

  8. High-sensitivity C-reactive protein and risk of sepsis.

    Directory of Open Access Journals (Sweden)

    Henry E Wang

    Full Text Available BACKGROUND: Conventional C-reactive protein assays have been used to detect or guide the treatment of acute sepsis. The objective of this study was to determine the association between elevated baseline high-sensitivity C-reactive protein (hsCRP and the risk of future sepsis events. METHODS: We studied data from 30,239 community dwelling, black and white individuals, age ≥45 years old enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS cohort. Baseline hsCRP and participant characteristics were determined at the start of the study. We identified sepsis events through review of hospital records. Elevated hsCRP was defined as values >3.0 mg/L. Using Cox regression, we determined the association between elevated hsCRP and first sepsis event, adjusting for sociodemographic factors (age, sex, race, region, education, income, health behaviors (tobacco and alcohol use, chronic medical conditions (coronary artery disease, diabetes, dyslipidemia, hypertension, chronic kidney disease, chronic lung disease and statin use. RESULTS: Over the mean observation time of 5.7 years (IQR 4.5-7.1, 974 individuals experienced a sepsis event, and 11,447 (37.9% had elevated baseline hsCRP (>3.0 mg/L. Elevated baseline hsCRP was independently associated with subsequent sepsis (adjusted HR 1.56; 95% CI 1.36-1.79, adjusted for sociodemographics, health behaviors, chronic medical conditions and statin use. CONCLUSION: Elevated baseline hsCRP was associated with increased risk of future sepsis events. hsCRP may help to identify individuals at increased risk for sepsis.

  9. Focused ion beams using a high-brightness plasma source

    Science.gov (United States)

    Guharay, Samar

    2002-10-01

    High-brightness ion beams, with low energy spread, have merits for many new applications in microelectronics, materials science, and biology. Negative ions are especially attractive for the applications that involve beam-solid interactions. When negative ions strike a surface, especially an electrically isolated surface, the surface charging voltage is limited to few volts [1]. This property can be effectively utilized to circumvent problems due to surface charging, such as device damage and beam defocusing. A compact plasma source, with the capability to deliver either positive or negative ion beams, has been developed. H- beams from this pulsed source showed brightness within an order of magnitude of the value for beams from liquid-metal ion sources. The beam angular intensity is > 40 mAsr-1 and the corresponding energy spread is 1 Acm-2 and a spot size of 100 nm. Such characteristics of focused beam parameters, using a dc source, will immediately open up a large area of new applications. [1] P. N. Guzdar, A. S. Sharma, S. K. Guharay, "Charging of substrates irradiated by particle beams" Appl. Phys. Lett. 71, 3302 (1997). [2] S. K. Guharay, E. Sokolovsky, J. Orloff, "Characteristics of ion beams from a Penning source for focused ion beam applications" J. Vac. Sci Technol. B17, 2779 (1999).

  10. Radial convection of finite ion temperature, high amplitude plasma blobs

    CERN Document Server

    Wiesenberger, M; Kendl, A

    2014-01-01

    We present results from simulations of seeded blob convection in the scrape-off-layer of magnetically confined fusion plasmas. We consistently incorporate high fluctuation amplitude levels and finite Larmor radius (FLR) effects using a fully nonlinear global gyrofluid model. This is in line with conditions found in tokamak scrape-off-layers (SOL) regions. Varying the ion temperature, the initial blob width and the initial amplitude, we found an FLR dominated regime where the blob behavior is significantly different from what is predicted by cold-ion models. The transition to this regime is very well described by the ratio of the ion gyroradius to the characteristic gradient scale length of the blob. We compare the global gyrofluid model with a partly linearized local model. For low ion temperatures we find that simulations of the global model show more coherent blobs with an increased cross-field transport compared to blobs simulated with the local model. The maximal blob amplitude is significantly higher in ...

  11. High metal reactivity and environmental risks at a site contaminated by glass waste.

    Science.gov (United States)

    Augustsson, A; Åström, M; Bergbäck, B; Elert, M; Höglund, L O; Kleja, D B

    2016-07-01

    This study addresses the reactivity and risks of metals (Ba, Cd, Co, Cr, Cu, Ni, Pb, Zn, As and Sb) at a Swedish site with large glass waste deposits. Old glassworks sites typically have high total metal concentrations, but as the metals are mainly bound within the glass waste and considered relatively inert, environmental investigations at these kinds of sites are limited. In this study, soil and landfill samples were subjected to a sequential chemical extraction procedure. Data from batch leaching tests and groundwater upstream and downstream of the waste deposits were also interpreted. The sequential extraction revealed that metals in metals are released from pristine glass and subsequently largely retained in the surrounding soil and/or on secondary mineral coatings on fine glass particles. From the approximately 12,000 m(3) of coarse glass waste at the site, almost 4000 kg of Pb is estimated to have been lost through corrosion, which, however, corresponds to only a small portion of the total amount of Pb in the waste. Metal sorption within the waste deposits or in underlying soil layers is supported by fairly low metal concentrations in groundwater. However, elevated concentrations in downstream groundwater and in leachates of batch leaching tests were observed for several metals, indicating on-going leaching. Taken together, the high metal concentrations in geochemically active forms and the high amounts of as yet uncorroded metal-rich glass, indicate considerable risks to human health and the environment.

  12. High-frequency behavior of FeN thin films fabricated by using reactive sputtering

    Science.gov (United States)

    Hwang, Tae-Jong; Lee, Joonsik; Kim, Ki Hyeon; Kim, Dong Ho

    2016-08-01

    We used ferromagnetic resonance (FMR) and its relationship with the static magnetic properties to investigate the high-frequency behavior of FeN thin films prepared by using reactive sputtering. The FMR was observed in the frequency range from 2 to 18 GHz in the FeN films fabricated at a proper nitrogen flow rate (NFR). In those FeN thin films, a decrease in the saturation magnetization and a corresponding decrease of the FMR frequency were observed as the NFR was increased during the deposition. The external field dependences of the FMR frequencies fit the Kittel formula well, and the Landé g-factors determined from the fit were found to be very close to the free electron value. The high-field damping parameters were almost insensitive to the NFR. However, the lowfield damping parameters exhibited a high sensitivity to the NFR very similar to the dependence of the hard-axis coercivity on the NFR, suggesting that extrinsic material properties, such as impurities and defect structures, could be important in deciding the low-field damping behavior.

  13. [Cardiovascular reactivity to emotional texts in subjects with low and high level of psychoticism].

    Science.gov (United States)

    Lysenko, N E; Davydov, D M

    2011-01-01

    The article presents the results of comparative study of groups of subjects with low and high level of psychoticism. Heart rate, heart rate responses to inspiratory and expiratory Valsalva maneuvers, and blood pressure were measured before and after presentation of the texts with validated negative content in groups of subjects with low and high psychoticism scores. It was hypothesized that subjects with high level of psychoticism would be less engaged in the processing of negative contents of the texts and their physiological reactivity (physiological resources submitted for support of cognitive processing) would be less pronounced compared to subjects with low level of psychoticism. Significant main effect of psychoticism was obtained for changes in heart rate to expiratory Valsalva maneuver after presentations of the texts. Significant interaction effects of gender and psychoticism were obtained for systolic blood pressure. Other cardiovascular variables were not sensitive to the level of psychoticism. These effects of psychoticism were independent of other individual traits, such as neuroticism, extraversion, lie (social desirability), anger, trait anxiety and depression.

  14. Excitation of plasma waves by nonlinear currents induced by a high-frequency electromagnetic pulse

    Energy Technology Data Exchange (ETDEWEB)

    Grishkov, V. E.; Uryupin, S. A., E-mail: uryupin@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-03-15

    Excitation of plasma waves by nonlinear currents induced by a high-frequency electromagnetic pulse is analyzed within the kinetic approach. It is shown that the most efficient source of plasma waves is the nonlinear current arising due to the gradient of the energy density of the high-frequency field. Generation of plasma waves by the drag current is usually less efficient but not negligibly small at relatively high frequencies of electron–ion collisions. The influence of electron collisions on the excitation of plasma waves by pulses of different duration is described quantitatively.

  15. The theta-pinch - a versatile tool for the generation and study of high temperature plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Hintz, E. [Inst. fuer Plasmaphysik, Forschungszentrum-Juelich GmbH (Germany)

    2004-07-01

    The more general technical and physical features of theta-pinches are described. Special field of their application are high-ss plasmas. Two examples are analysed and studied in more detail: a high density plasma near thermal equilibrium and a low density plasma far from equilibrium. The latter is of special interest for future investigations. Possibilities of field-reversed configurations are pointed out. (orig.)

  16. Vacuum ultra-violet damage and damage mitigation for plasma processing of highly porous organosilicate glass dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Marneffe, J.-F. de, E-mail: marneffe@imec.be; Lukaszewicz, M.; Porter, S. B.; Vajda, F.; Rutigliani, V.; Verdonck, P.; Baklanov, M. R. [IMEC v.z.w., 3001 Leuven (Belgium); Zhang, L.; Heyne, M.; El Otell, Z.; Krishtab, M. [IMEC v.z.w., 3001 Leuven (Belgium); Department of Chemistry, KULeuven, 3001 Leuven (Belgium); Goodyear, A.; Cooke, M. [Oxford Instruments Plasma Technology, BS49 4AP Bristol (United Kingdom)

    2015-10-07

    Porous organosilicate glass thin films, with k-value 2.0, were exposed to 147 nm vacuum ultra-violet (VUV) photons emitted in a Xenon capacitive coupled plasma discharge. Strong methyl bond depletion was observed, concomitant with a significant increase of the bulk dielectric constant. This indicates that, besides reactive radical diffusion, photons emitted during plasma processing do impede dielectric properties and therefore need to be tackled appropriately during patterning and integration. The detrimental effect of VUV irradiation can be partly suppressed by stuffing the low-k porous matrix with proper sacrificial polymers showing high VUV absorption together with good thermal and VUV stability. In addition, the choice of an appropriate hard-mask, showing high VUV absorption, can minimize VUV damage. Particular processing conditions allow to minimize the fluence of photons to the substrate and lead to negligible VUV damage. For patterned structures, in order to reduce VUV damage in the bulk and on feature sidewalls, the combination of both pore stuffing/material densification and absorbing hard-mask is recommended, and/or the use of low VUV-emitting plasma discharge.

  17. Formation of distinctive structures of GaN by inductively-coupled-plasma and reactive ion etching under optimized chemical etching conditions

    Directory of Open Access Journals (Sweden)

    N. Okada

    2017-06-01

    Full Text Available We focused on inductively coupled plasma and reactive ion etching (ICP–RIE for etching GaN and tried to fabricate distinctive GaN structures under optimized chemical etching conditions. To determine the optimum chemical etching conditions, the flow rates of Ar and Cl2, ICP power, and chamber pressure were varied in the etching of c-plane GaN layers with stripe patterns. It was determined that the combination of Ar and Cl2 flow rates of 100 sccm, chamber pressure of 7 Pa, and ICP power of 800 W resulted in the most enhanced reaction, yielding distinctive GaN structures such as pillars with inverted mesa structures for c-plane GaN and a semipolar GaN layer with asymmetric inclined sidewalls. The selectivity and etching rate were also investigated.

  18. Formation of distinctive structures of GaN by inductively-coupled-plasma and reactive ion etching under optimized chemical etching conditions

    Science.gov (United States)

    Okada, N.; Nojima, K.; Ishibashi, N.; Nagatoshi, K.; Itagaki, N.; Inomoto, R.; Motoyama, S.; Kobayashi, T.; Tadatomo, K.

    2017-06-01

    We focused on inductively coupled plasma and reactive ion etching (ICP-RIE) for etching GaN and tried to fabricate distinctive GaN structures under optimized chemical etching conditions. To determine the optimum chemical etching conditions, the flow rates of Ar and Cl2, ICP power, and chamber pressure were varied in the etching of c-plane GaN layers with stripe patterns. It was determined that the combination of Ar and Cl2 flow rates of 100 sccm, chamber pressure of 7 Pa, and ICP power of 800 W resulted in the most enhanced reaction, yielding distinctive GaN structures such as pillars with inverted mesa structures for c-plane GaN and a semipolar GaN layer with asymmetric inclined sidewalls. The selectivity and etching rate were also investigated.

  19. Stress-induced VO{sub 2} films with M2 monoclinic phase stable at room temperature grown by inductively coupled plasma-assisted reactive sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Okimura, Kunio; Watanabe, Tomo [School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan); Sakai, Joe [GREMAN, UMR 7347 CNRS, Universite Francois Rabelais de Tours, Parc de Grandmont 37200 Tours (France)

    2012-04-01

    We report on growth of VO{sub 2} films with M2 monoclinic phase stable at room temperature under atmospheric pressure. The films were grown on quartz glass and Si substrates by using an inductively coupled plasma-assisted reactive sputtering method. XRD-sin{sup 2}{Psi} measurements revealed that the films with M2 phase are under compressive stress in contrast to tensile stress of films with M1 phase. Scanning electron microscopy observations revealed characteristic crystal grain aspects with formation of periodical twin structure of M2 phase. Structural phase transition from M2 to tetragonal phases, accompanied by a resistance change, was confirmed to occur as the temperature rises. Growth of VO{sub 2} films composed of M2 phase crystalline is of strong interest for clarifying nature of Mott transition of strongly correlated materials.

  20. High-Sensitivity C-Reactive Protein as a Predictor of Cardiovascular Events after ST-Elevation Myocardial Infarction

    Science.gov (United States)

    Ribeiro, Daniel Rios Pinto; Ramos, Adriane Monserrat; Vieira, Pedro Lima; Menti, Eduardo; Bordin, Odemir Luiz; de Souza, Priscilla Azambuja Lopes; de Quadros, Alexandre Schaan; Portal, Vera Lúcia

    2014-01-01

    Background The association between high-sensitivity C-reactive prot